openME 54.2

TECH: DEEPFAKES

ASSOCIATION: 5 YEARS OF OPENME

July

ASSOCIATION: LANDYACHTING

TRAILER

JOIN A COMMITTEE AT W.S.V. SIMON STEVIN

Freshmen committees

• AcCie

• BattleCie

• ReAcCie

General committees

• BeerBrewing

• Cooking

• Editorial

• LandYachting

• Photo

• WebCie

Activity committees

• Crafting

• Women

• BACo

• ConstructionContest

• SimonCamp

• Introcommittee

• ParTee

• Tripcommittee

Carreer committees

• Convent

• ExpoCie

• Symposium

If you are intrested feel free to contact the Board in De Weeghconst (Traverse 0.34) or send a mail to bestuur@simonstevin.tue.nl

FOREWORD

Dear reader,

e word “gifted” has two meanings: a naturally exceptional ability or a given gift. roughout this edition of the openME, these two definitions can be found back. e first and most important one is that we can celebrate that we have been gifted 5 years of the openME, making this the first Lustrum of the openME. For this reason, we figured out who contributed the most in the past 5 years to make the openME possible, together with some other interesting statistics.

Furthermore, we will take a look at gifted people that do extremely complex work in their PhD, go far away abroad to finish their master, or quite simply by taking look at the people that help make education at the TU/e possible. Furthermore, you can read about gifted people who make exceptional things in the many fascinating tech articles about subjects like fusion reactors, the butterfly e ect, or the latest and greatest gift AI.

We will also focus on the talented people in the Association who made the Land Yachting trailer possible. Next to that, you can read about the greatest gift on our university: free co from study associations, and who has the best. Lastly, you can also learn about the things that you see every day, but never really appreciate as much as you should: the campus art.

All in all, there is plenty to read about in this edition of the openME and I want to thank the gifted committee and other people that helped make this edition possible!

I wish you a lot of reading pleasure!

With kind regards,

Ben Gortemaker Editor-in-Chief

INTERNSHIP AUSTRALIA WRITTENBY

MAARTJEBORST

February 2022, Australia finally decided to open their borders again to foreigners after two years. This was the perfect opportunity for me to travel to the other side of the world to finish the last part of my master’s degree, the internship. For a little over three months I spend my time at Deakin University in Geelong, Victoria. In this journal, I will give some insight into my project, my life in Australia and my adventures after my internship.

Internship

During my internship I designed, fabricated and evaluated a 3D-printed device for particle focusing in non-Newtonian viscoelastic microfluidics to separate particles. In this journal, I will first explain the importance of separating particles. Thereafter, I will explain what a non-Newtonian viscoelastic fluid is. I will end this part with my 3D-printed device and the final result.

The continuous separation of micron-sized particles or cells is an important tool in a wide range of fields, including disease diagnostics, chemical analysis, food and chemical processing, and environmental assessment. Conventionally, particles can be separated using centrifugation orfiltration methods.

Figure 1: Relationship between the viscosity and shear stress for Newtonian and non-Newtonianliquids.

Particles can also be separated using microfluidics, which uses smaller sample volumes, high accuracy, low costs and is fast in comparison to the conventional separation methods.

There are two types of liquids, Newtonian and non-Newtonian liquids. The di erence between a Newtonian and a nonNewtonian fluid is the behaviour of the viscosity. The viscosity is a parameter that explains how easily a liquid can flow. This parameter is dependent on the shear stress and shear rate and thus the force. The relationship between the shear rate and shear stress is linear for a Newtonian fluid as shown in Figure 1, resulting in a constant viscosity and thus independent of how much force is applied to the liquid. An example of a Newtonian liquid is water.

The viscosity of a non-Newtonian fluid is dependent on the forces applied to the liquid. An example of a non-Newtonian fluid is toothpaste. Toothpaste will not flow out of the tube whenyou don’tpushthetube. Ifyou applyforce onthetube,the toothpaste will become more viscous and flows out of the tube.

Non-Newtonian viscoelastic fluids can be used to realize 3D particle focusing in a microchannel because viscoelastic e ects influencethepositionofaparticleinafluidstream.Thisfocusing and separation are mainly investigated in devices made with a soft-lithography process using Polydimethylsiloxane (PDMS). A schematic representation of the soft-lithography process can be seen in Figure 2. The first step is to make a mould, by using a light-sensitive photoresist. Using a mask allows you to create a pattern in the photoresist by shining UV light onto the photoresist. Depending on the photoresist you can either dissolve or retain the structure by washing it with a developer. By pouring PDMS onto this mould and baking this, you can create structures which can be bonded to a glass plate to create channels.The disadvantage technique is thatyou are not able to make non-planar structures. Besides that, it is expensive and hard to commercialize.

Figure 2: Schematic representation of the softlithography process.

Figure 4: 200 x 200 µm.

Figure 3: 500 x 500 µm.Figure 5: 100 x 100 µm.

As the possibilities with additive manufacturing, better known as 3D printing, increase, this can be an alternative to soft-lithography devices. Therefore I designed, fabricated and evaluated a 3D-printed device for particle focusing in viscoelastic microfluidics.

The first challenge was to make a microchannel with a height and width of only a few hundred micrometer. As a reference, the thickness of a single hair is about 100 μm using. According to the supplier of the 3D printer, 100 μm squared channels can be made pushing the printer to its absolute limits. So, these dimensions can only be reached in perfect conditions. After optimizing the parameters, I was able to print microchannels. Figures 3 to 5 show the cross-section of three di erent-sized microchannels.

Thequestionleftwaswhetherwewereabletoaligntheparticles inthis3D-printedchannel.Imixedanon-Newtonianviscoelastic fluid with some spherical microparticles. This mixture was pushed into the channel. With a microscope and a high-speed camera, I was able to see the behaviour of the particles in the channel.Andto all ourhopes,wewere ableto alignthe particles in one straightline in the channel as shown in Figure 7.

All-in-all a step is made in understanding the behaviour of particles in viscoelastic fluids using 3D-printed microchannels. The results were surprising. Together with my supervisors Rosanna Guijt and Dan Yuan, we decided to write a scientific paper aboutthis. Interested tolearn more about myresults, feel free to contact me.

Figure7:Exampleofparticlesaligningin3Dprinted microchannel.

Figure 6: My own 3D-printed device. The channel is a 200 µm squared channel with a total length of 6.5 cm.

LifeinAustralia

Looking back at my time, it was ones in a lifetime experience. Of course, it is a bit scary in the beginning being by yourself on the other side of the world, but foremost it is exciting.

The e ects of covid were definitely still visible at the time I visited Australia. The number of students that came to the university to follow classes was low. Lots of students still followed their classes online.LuckilyIfoundaplacetostayinthestudentareaofGeelong and created some nice friendships.

Living in Geelong is quite comparable to living in Eindhoven. The region around Melbourne, including Geelong, is seen as the most European part of Australia. Therefore cultural di erences are limited. The biggest di erence with living in Eindhoven is public transport. In Australia, public transport is very limited and thereforeyoudefinitelyneedtohaveacartobringyouto aspecific location. Luckily all my friends had a car and were in for some fun activities,likehiking and wine tasting, during the weekend.

Iamgoingonanadventure….

After spending three months working on my 3D print project it was time for me to leave Geelong. Luckily I did not have to leave Australia yet as I only spend my time around the region of Melbourne. Together with my boyfriend Otto, we decided to travel first toAustralia and thereafter to New Zealand.We started our journey in Cairns, which is in the North East of Australia, where we did a five-day diving course in the Great Barrier Reef. If you ever get the chance to do this while it is still there, I would definitely recommend it! From Cairns, we travelled all across the EastCoastwhereweendedourjourneyinAustraliainthebigcity, Sydney.

From there we flew to Auckland where we spend almost two months in a small rented campervan travelling around the North and South Islands of New Zealand. Travelling with a campervan enabled us tovisit all the ‘undiscovered and untouched’ places in nature. These places were varying from climbing and walking up a big mountain and looking over big gletsjers to swimming in hot waterpoolsnearthebeach.Asitisallowedtodofreedomcamp in destinated places, you can camp at movie-like and almost unreal places, which were maybe one of the most exciting times.All-inall, these six months was atime never to forget.

DEALING WITH THE SCORCHING EXHAUST OF A TOKAMAK

The world-leading fusion reactor ITER will start operating in the coming decade and more companies are joining the race to realize nuclear fusion all working on the final technological challenges which must be solved before fusion energy can power our grids. One of these challenges is dealing with the extreme exhaust of a fusion reactor, which pushes the limits of material science, plasma physics and control engineering.

WRITTENBYLENNARDCEELEN

Our society faces a significant challenge to transition towards renewable energy sources. In a fusion reactor, we try to harvest the energy produced by fusion reactions, specifically the reaction of fusing the hydrogen isotopes deuterium and tritium intoheliumandahighenergyneutron,as illustrated inFigure 1.

The fusion reaction does not emit greenhouse gas and only produces shortlivednuclearwaste andunlike windand solar PV, fusion energy can produce a robust baseline of power to our grids.

Reachingandmaintainingtheconditionsforfusionreactions onearth ischallenging.The temperature required for energy production is 150 million degrees Celsius. At this extreme temperature, electrons are stripped from the deuterium and tritium atoms and become ions, forming a hot cloud of charged particles called a plasma: the fourth state of matter.

Figure 1: The fusion reaction fusing deuterium (2H) and tritium (3H) into helium (4He) and releases a highenergyneutron(n),withtheunit1eV=1.6*10-19 J.This reactionreleasesfourtimesmoreenergythanuranium fissionatequalmass.

Figure 2: The tokamak reactor concept, consisting of a large set of (superconducting) magnetic coils (blue) creating a strong donut-shaped magnetic field (green & black arrows). The magnetic fields imprisons the fusionplasma(purple).(adopted fromIPP)

A fusion reactor must confine this scorching fusion plasma, and the furthest developed reactor concept is the tokamak. A tokamak imprisons the plasma in a donut-shaped magnetic field, as shown in Figure 2. The plasma that escapes the magnetic cage is directed toward the divertor, as illustrated in Figure 3. The divertor is responsible for safely exhausting the helium by-product and its energy. and therefore exposed to extreme heat loads.. If left unattended, the divertor will be destroyed instantly. Hence, methods are necessary to reduce the heat of the plasma exhaust before it reaches the divertor. As anexample,let’sconsiderthe numbersoftheITERtokamak. The expectedheatloadenteringthe exhaustinITERis100 MW/ m2 . To put this number into perspective, the maximum heat load sustained by a space shuttle’s heat shield during re-entry is 1 MW/m2[1].

These extreme conditions have led to scientists pushing the limits of material science and engineering to develop a divertor to manage these heat loads. The divertor solution in ITER consists of 300.000 actively cooled monoblocks [2], as shown in Figure 4 .

The monoblocks consist of tungsten because of its high melting temperature of 3400 °C. They are actively cooled with water flowing through a copper pipe. Moreover, these monoblocks must be manufactured and positioned with millimeter precision to evenly distribute the plasma exhaust. These monoblocks are designed to endure a heat load of 15 MW/m2[3]. Hence, additional methods are necessary to reduce the 100 MW/m2 in the exhaust to acceptable levels.

Apromisingstrategyis injectingimpuritygases inthe divertor region, which dissipates the power of the plasma exhaust by radiation. As a result, the heat load is reduced before it reaches the divertor, basically creating a radiative bu er of gas above the monoblocks. However, we want to prevent too much impurity gas from being injected and reaching the core plasma. Since, in the core plasma, the impurity gases also radiate power, reducing the fusion performance of the tokamak. Consequently, the injection of impurity gas needs to be controlled such that the heat load in the divertor is acceptable while optimizing the fusion performance of the core plasma.

Designing a safe feedback controller requires a controloriented dynamic model of the plasma exhaust and impurity gas injection. Understanding the physics that govern these dynamics iscurrentlyanactivefieldofresearch and necessary for the safe operation of a tokamaklike ITER.

Besides ITER’sheatload mitigation strategy,newsolutions are beingexplored.MIT’sspin-o CommonwealthFusionSystems (CFS) is developing the exciting ARC tokamak (Remember Tony Stark?). This tokamak will have two divertors to divide the plasma exhaust, as shown in Figure 5. Another innovation explored is replacing the divertor monoblocks with liquid metal [6], aswhatis alreadymolten cannotmelt.Anexample is showninFigure6,whicho ers a3D-printedtungstenelement with an intelligent geometry that replenishes liquid lithium to the surface with capillary forces.

[1] Meese, E.A., & Nørstrud, H. (2002). Simulation of convectiveheat flux andheat penetration for a spacecraft at re-entry.Aerospace Science andTechnology, 6(3), 185–194.

[2] Prototype | Thehottest f in ITER. (n.d.). Retrieved January

7, 2023

[3] .Technology| Commonwealth Fusion Systems. (n.d.). Retrieved January7, 2023

Figure 5: Concept of ARC tokamak from CFS. The tokamakhastwo divertors [5].

Figure 4: A divertor cassette prototype (1.5 m) [4]. ITER’s divertor ITER will consist of 54 cassettes of 3.5mlong.

Figure 3: Cross section of a tokamak. The hot plasma that escapes the magnetic cage is the plasmaexhaustandisdirectedtowardsthedivertor. (AdoptedfromITER)

We have seen the challenges and solutions for dealing with the enormous exhaust of a tokamak reactor. This challenge is part of many, and several developments are necessarybeforenuclearfusion can power our grids. Solving these challenges require many more engineers and physicists before we can unleash the potential of fusion energy and power in our societies. Besides its primary importance as an energy source. Fusion energy also operates at the frontiers of material science, physics, control and is a fascinating field of research.

The TU/e o ers a Master’s program in Science and Technology of Nuclear Fusion, compatible with a Master’s in mechanical engineering.Furthermore,theDutchinstituteforfundamental energy research (DIFFER) is located in Eindhoven. DIFFER is a world leader in developing liquid metal divertor materials and plasma modeling.

Let’s discuss my graduation project at DIFFER and General Atomics as an example of possible projects you can do with a Mechanical Engineering Bachelor and Fusion Master. General Atomicshosts the DIII-D tokamakin San Diego,where I stayed for a couple of months to run experiments. The research objectives of my experiments are:

1. Provide a benchmark for control-oriented models of the plasma exhaust by performing system identification on the DIII-D tokamak.

2. Design and implement a divertor radiated power feedback controller in the DIII-D tokamak.

We have seen that for the safe operation of tokamaks like ITER, we need control oriented dynamic models of the plasma which we can validate these models with system identification experiments on DIII-D. Furthermore, we can use these same models to design a controller for the plasma exhaust. We performed system identification experiments with multisinusoidal impurity gas injection. We measured the dynamic response of the power radiated from the divertor with a diagnostic, as shown in Figure 7. With this data, we estimate the frequency response function of the plasma exhaust, which can be used for model validation.

Furthermore, we have seen earlier that controlled impurity injection can mitigate the heatload at the divertor. Developing this controller in DIII-D is our second objective. To this end, we have designed a PI controller using the frequency response measurements from the multi-sines.

A feedback experiment is shown in Figure 8, which shows that the controlled impurity injection tracks an increase in the radiated power reference and thus reduces the divertor heat load.

Besides dynamics, control and system theory, mechanical engineers can also contribute with di erent disciplines. Since material science can help create materials that endure larger heatloads and studythe e ect on thermal cycling and fracture mechanics. Furthermore, 3D printing ofthetungsten elements can be improvedwith topologyoptimization, andthe materials must be compatible with the corrosive liquid metal. At last, fluid and transport simulations are necessary to develop and design liquid metal solutions and to model the complex interaction between the plasma and the impurity gas.

I hope you have become excited about nuclear fusion and will join our e orts toward a future with sustainable energy production!

injection. Objective 2: Design and implementradiatedpower controller.

[4]Vapor shielding can regulate temperature of fusion reactorwalls | Dutch Institute for Fundamental Energy Research.

(n.d.)

Figure 8: Example of a controlled feedback experiment. The radiated power is controlled with impurity gas injection during an experiment.

Figure 7: Objective 1: Identify divertor dynamics with multi-sine gas

Figure 6: A 3D-printed tungsten element, with a tree like structure to replenish the surface with liquid lithium by capillaryforces[4].

MATERIAL SCIENCE OF A FOOTBALL

WRITTENBYTOMSLANGEN

Football is something that goes a long time back. In 1872 the first international football match was played between England and Scotland. Futsal is a variant that was created out of football. It only consists of 5 players in the field and the matches only take 20 minutes. The study association Simon Stevin also has one team which is active in the student futsal competition. Almost every week they play a match during the lunch break.

The name of the team was created in a funny way. During the exam weeks a lot of people study in Metaforum, a building on theTU/eCampus.Onfloorzerotherearealotofdi erenttables. All these tables areverypopulated duringthe examweeks. Most of the team members choose to sit at table 19. This is where the team name was born.

The bounce is 30 percent less for a futsal ball. It makes sense to make a futsal ballless bouncy. There are many players perteam in futsal, which makes the field very crowded. Compared with a standard soccer field, the futsal field is very small, with plenty of tightspaces.A bouncyfutsal ballwill cause the playerstolose the ball significantly more. This is because it will bounce away from them a lot more when trying to trap it. An opponent will almost always steal the ball as soon as it bounces o a bit.

The ball is made less bouncier by adding some extra material to the ball. In a normal football the inside ball consist of air. The bladder is fully empty inside, and is filled with air. When that bladdercomes intocontactwith afoot,the shockthatitreceives will be given to the ball and it will fly. Next to this it makes the ball lighter because it only contains air.

The competition in which the team participates, is not the best competition. Even though the competition is not the highest, the team does not perform very well. However there was one good win achieved by the team. The match was very exciting, because the teams were both equal in level. When the win was achieved, the whole study association thought match fixing had taken place. The referee was not the problem, but the ball was. That is whywewilllook atthe material science of a futsal ball.

First there will be looked at the di erence between a futsal ball andafootball.Thesportsvaryquitefromeachotherandsodoes the ball. A futsal ball is a size 4 and the football is size 5. Size 4 is between 63.5-66.04 Centimeters. Size 5 is between 68.58-71.12 Centimeters. Next to the size of the ball, the futsal ball has a 30 percent less bounce. The reason for the smaller ball is because the goals are also smaller compared to football. If the balls were the same size, itwould be too easy forthekeeperto catch it.

Thematcheswillgofastifafutsalballwasthesameasafootball. The ball is bigger which makes controlling the ball easier. The velocity of the ball will also increase. The goal keeper can catch the ball easier because it is bigger, but the velocity of the ball in increased and thus it will be easier to score. The ball would go too fast for a small field inside.

In a futsal ball the bladder is filled with a stu ng, which can be foam or cotton. Due to this stu ng, less air can be pumped into the bladder. The weight of the ball is increased. More force is needed to give it the same velocity as a normal football. This stu ngalsodeadenstheshock.Theimpulsofafutsalballneeds tobehighertogiveitthesamevelocity. Thepicturebelowshows out ofwhat materials a ball exists.

Now the di erences between a futsal ball and a normal football are known. There is still no logical explanation how the team could of won. The team is still very happy that the match was won. Howeverthe team is tryingtokeep up the goodwork. Next season the teamwill go for promotion!

STUDENT COOKING: THE PARTY HARDY EDITION

After some dark, cold months, it is finally the time of year again in which everything is in bloom. Not only in nature, but also in student life. From outside drinks to student tournaments and from fun trips to late night festivities in the Peppers (which we of course also visit in those cold months): Q4 is party quartile. Obviously, it is important to eat well during these fun times. With these recipes, the party is on!

‘Bodempjeleggen’

Before going to an amazing festivity, where you will have lots of drinks, you need to ‘leg a bodem’, which means that you have to eat well. The night is going to be long and your body needsnutrients.Ifyouchoosetherightfood,the

food will absorb part of the alcohol. Next to the fact that it is important to get in your vitamins, a greasy snack never hurts. This is because a greasy snack decelerates the absorption of alcohol.A Mexicanwrap is delicious!

BODEMPJE LEGGEN

Whatdoyouneed?

• Paprika

• Lettuce

• Corn

• Wrap

• (Vega) minced meat

• Taco spices

• Cheese

• Avocado

• Guacamole spices

• Sourcream

Howdoyoumakeit?

1. Followthe instructions on the packaging of thewraps.

2. Bakethe (Vega) minced meatand corn in a pan.Add the taco spices.

3. Slice the avocado and mash it.Add the guacamole spices.

4. Slice the paprika.

5. Buildyourown Mexicanwrap!

WRITTENBYIMKEGOOFERS

Beforeyougotosleep...

You have had the night of your life and danced all night long on your favorite ‘hitjes’. You also very much enjoyed your beers and shots, of whichyouhavehad alittletoo many...

To avoid the hangover as much as possible, it is important to get in some salt and moisture beforeyou goto sleep.A delicious ‘Unoxsoep in zak’combines best of bothworlds!

BEFORE YOU GO TO SLEEP

Whatdoyouneed?

• Soup

Themorningafter

When you wake up, you will probably say to yourself: ‘Never again’. But shortly after that, you realize that you say this to yourself every week. You have had a great night, so you have a great headache. You are going to make the best outofthis‘brakke’day.Andyouknowwhatthey

Howdoyoumakeit?

1. Followthe instructions on the packaging. Followingthese instructions is nothard, evenwhen you area bitdrunk ;)

say: good food, good mood. Let’s make some breakfast!

Enjoyalltheactivitiesthatareplannedinthelast quartile of the academicyear.And, bon appetit!

THE MORNING AFTER

Whatdoyouneed?

• Paracetamol

• Lots ofwater

• Eggs

• Unsalted butter

• Milk

• Saltand pepper

• Bacon

• Slice of bread

Howdoyoumakeit?

1. Starto the daywiththe usual paracetamol (ortwo) and chuck a glass ofwater.

2. Beatthe eggs andwhisk until the yolk andwhites arethoroughly combined.

3. Addthe milk andwhisk again.

4. Heatthe pan and pourinthe egg mixture.

5. Letthe mixture cook undisturbed forafewseconds.

6. Pull aspatulaacrossthe bottom of the panto formlarge, softcurds of scrambled eggs.

7. Repeatthe process.

8. Putthe scrambled eggs onthe slice of bread and add some baked bacon to it.

MEET THE TEACHER SUPPORTOF MECHANICAL ENGINEERING

WRITTENBYAPOORVASONAWANE

As of January, I am one of the new Teacher Supporters at the Department of Mechanical Engineering. I am from India and have been living in the Netherlands foralmost 5years now. I obtained my master’s degree in Educational Psychology from the University of Twente; and I also worked here for the past two and a half years as a teacher in the Psychology bachelor program.

During my master thesis, I looked into the implementation of the Jigsaw method and worksheets to support collaborative learning for eighth grade students at a school in India. This project showed me the potential of collaborative learning, what the conditions for are fir this to be e ective, how students canbesupported,andwhatIcando,asaninstructor,tofacilitate e ectivecollaboration.Duringmyproject,notonlydidIdevelopana nity to support students’ learning in groups, I also continued to learn more about it. Sincethen, asateacher,Ihavehadtheopportunitytoputmylearningintopractice. In this job, I loved working with students from di erent educational and cultural backgrounds. I valued transparency in teaching and wanted to keep developing on the aspect of providing valuable formative feedback. As I continued with teaching, I found myself wanting to do morewith designing education and in the future, also working on contributing to teacher’s their professional development.

That’swhatbrings meto mynewchallenge asateachersupporter!Inthis role, I am involved in various tasks such as supporting with (re)designing courses, working on the implementation of challenge based learning, but also UTQ coordination, etc. I hope that during my time here I can, togetherwith my colleagues, contribute to educating engineers for the future. In doing so, I am certainly also looking forward to working with Simon Stevin as students are central to the education we o er. Of course, I’ve been a student not too long ago myself, and I believe I can bring this perspective to my work. As I embark on my new role, I am curious about the possibilities for many interesting collaborations and new educational developments.

Outside ofwork, I spend mytime baking, going on smallhikes and always learning about (and brewing) co ee! I like learning new languages, so I am, of course, in pursuit of learning Dutch.

I hope we can meet at one of the Simon Stevin drinks (or other activities) soon!

OBTAINING AND MAINTAINING AN ACCURATE DIGITAL TWIN OF A DYNAMICAL SYSTEMS USING ARTIFICIAL INTELLIGENCE

PHD PROJECT

A digital twin is avirtual tool (containing a mathematical model) representing a realworld physical system that allows for relatively inexpensive decision-making during its entirelifecycle. Obtaining an accurate digital twin proofs to be di cult in practice, however.Moreover, maintainingitsaccuracy duringtheoperationallifeofthesystem is far from trivial as well. The goal of my PhD project, of which I am currently in the third year, therefore, is to develop a model updating technique that updates a digital twin using data measured on its real-world counterpart. To achieve this, I employ Artificial Intelligence (AI) to learn the complex inverse relations between measured data and underlying parameter values of the model.

WRITTENBYBASKESSELS Phd Student Dynamics & Control

Introduction

With the increased availability and quality of electronic components such as integrated circuits and sensors, the fourth industrial revolution is currently in full swing. Part of this revolution is the advent of digital twins. A digital twin is a virtual representation of a machine, system, or production process, constituted by a model describing the (dynamical) behavior of the system under given inputs. Using the digital twin, di erent operating conditions can be tested without the high costs typically associated to equivalent tests on the physicalsystem.Havingamoreaccuratedigitaltwinalsoallows formodel-basedcontrol,potentiallyenhancingperformanceof the physical system.Additionally, Structural Health Monitoring (SHM) is facilitated, allowing for predictive maintenance that can greatly reduce valuable down time of a machine.

In this research, the motion stage of an ASMPT wire bonder, showninthetopleftimageinFigure1,servesasthemainusecase. Awirebonderisusedinthe semiconductorindustrytoconnect an Integrated Circuit (IC) to other electronic components by connecting them with many small gold wires. Due to the small scaleofICs,themotionstagerequiresaccuraciesinmicrometer or even sub-micrometer range. Furthermore, to accommodate a high throughput, accelerations of more than 200 m/s2 are required. Consequently,ahigh-fidelitymodel ofthis 3D motion stage is required to serve as digital twin.

As a digital twin of this machine, a dynamical (multi-body) model that is derived from First-Principles (FP) is used. In

practice, due to manufacturing tolerances, machine-tomachine variations exist. Therefore, the (FP) model of the machineshouldbeupdatedsuchthateachmachinegetsitsown dedicated digital twin. Furthermore, due to wear, components might deteriorate over time, leading to changing behavior. For thisreason,thedigitaltwinsshouldalsobeupdatedthroughout their operational life. In this research, so far,wehave primarily focused on updating model parametervalues.

To be applied in a digital twin context, model (parameter) updating should be performed online in (near) real-time, i.e., very fast, and should be physically interpretable. Additionally, we would like the developed methodology to be applicable for a broad range of models. In a dynamics context, for example, nonlinear dynamics models are considered which may be derived using FPs or obtained via simulation software (such as Simulink/Simscape).

Currently existing parameter updating methods, however, do not satisfy these joint requirements. Therefore, we have developed anAI methodologythatemploys supervisedlearning to map measured signals to physically interpretable parameter values. These parameter values are subsequently used to reparametrize (or update) the original model. As a result, signals simulated using the updated model, closely resemble the measured signals, thus indicating an accurately updated digital twin.

Figure 1: (Inverse mapping) parameter updating process for ASMPT wire bonder. Picture of physical wire bonder motion stage (top left) courtesy of ASMPT. Note that the ‘measured’ signal shown in this figure is a simulated measurement (with artificial measurement noise).

InverseMappingModel

Mapping the measured signals to parameter values is tackled bydeveloping an Inverse Mapping Model (IMM). Consequently, this methodology is referred to as the Inverse Mapping Parameter Updating (IMPU) method, which is schematically shown in Figure 2.

Since the required inverse mapping is very complex, we train a supervised machine-learning-based regression model to constitute the IMM. For example, we can use an Artificial Neural Network (ANN). Alternatively, in an internship, we have employed Gaussian Processes (GPs) to quantifythe uncertainty in the estimated parameter values. To train the IMM, training data is generated o ine (see blue boxes in Figure 2) by simulatingtheparametricmodelforasetofdi erentparameter value combinations. From the resulting simulated signals, sets of features are extracted that condense the information in the measured signal and represent the dynamics of the model for a set of di erent parametervalue combinations. Here, multiple

feature types can be chosen. For example, measured time samples of the signal can be used directly. Alternatively, the measured signal can be transformed to the frequency domain first, such that only data corresponding to relevant frequency ranges are taken into account. In a recent internship, we have explored the opportunity to automatically select a small subset of features to further increase accuracy and computational e ciency.

After having generated the training data, i.e., sets of features (inputs to the ANN) and corresponding parameter values (outputs of the ANN), in Matlab, the training data is imported toPythontotraintheANN.Here,apre-specifiedANNstructure andtrainingsettingsareused.Inarecentbachelorfinalproject, we have tuned these so-called ANN-hyperparameters using Bayesian searches.

Figure 2: Schematic representation of the IMPU method with the offline and online phase.

Figure 3: Relative estimation errors for a selection of updated parameters.

Having trained the IMM/ANN, in the online phase (orange boxesin Figure2),weperformameasurementonthephysical system (so far in this study we, however, use simulated measurements), for which we use the same excitations and initial conditions as for the training data generation. Then, features are extracted from the measured signals and used as input to the trained IMM. The inferred outputs of the IMM are the updated parameter values. Inferring these parameter values only takes a couple of milliseconds, since the majority of the computation time is shifted from the online phase to the o ine training phase.

Testresults

As we do not know the true parameter values of the physical system(thisistheveryproblemwearetryingtosolve),wehave to test the methodology by simulating a measurement using our model with known parameter values. Using the features extracted from these simulated measurements as input to an (already) trained ANN, parameter values are inferred which are compared to the (known) true parameter values. Doing this formultiple testsamplesyieldshistograms of the relative parameter estimation errors for each updated parameter, see Figure 3. This figure shows that parameter estimates are accurate to within (at most) 2%. Consequently, the model updated using the estimated parameter values serves as an

accurate digital twin. To illustrate this, in the top right plot in Figure 1,the signal obtained bysimulatingthe updated digital twin (orange) closely resembles the measured signal (blue).

Ongoingresearch

In the work done so far, we have focused solely on updating parametervaluestodecreasethemismatchbetweenamodel/ digital twin and a physical system. Often, however, this mismatch is (also) partly caused by an inaccurate structure of the model. In ongoing research, together with two MSc. students,Iamthereforeaimingtoupdatethestructuremodel as well. More specifically, these projects aim at augmenting the existing model (adding unmodelled terms such as complex friction terms to the existing equations of motion) and extending the equations of motion with new degrees of freedom (for example to add flexibility degrees of freedom to an originallyrigid-bodymodel). Finally, I am reallycurious to discover how the techniques that I developed can be applied on a physical machine of the ASMPTwirebonder. This will be investigated in thelast part of myPhD.

Feel free to contact me for questions about this research or opportunities for a student-projectvia b.m.kessels@tue.nl.

is publication is part of the project Digital Twin project 2 with project number P18-03 of the research programme Perspectief which is (partly) financed by the Dutch Research Council (NWO).

MIND CONTROLLED ROBOTS

WRITTENBY:RYANLEAL

Mind control robots are an emerging field of research that seeks to create robots that can be controlled directly by the human mind. They are designed to detect and interpret electrical signals in the brain, allowing users to control the robot’s movements, actions, and functions through their thoughts alone. Several universities around the world are actively conducting research on mind control robots, one being the University of Sydney in Australia. In a recent study, researchers at this university developed a mind-controlled robot that could navigate a maze using brain signals. The study involved placing electrodes on the scalp of the user to detect their brain signals and sending these signals to the robot, which then moved through the maze based on the user’s thoughts.

variety of scenarios and environments. Graphene material, a carbon consisting of planar sheets that is unique in its thinness and conductivity, is used for the sensors which are positioned on the back of the scalp, being the link between the electrical brain signals and the robotic systems. Silicon is usually used in the construction of the electronics and microprocessors inside the robot, while robots themselves are mostly constructed out of materials such as aluminium, steel, or composites which are specifically designed to o er the necessary strength, sti ness, and durability to perform tasks.

Mind control robots have a wide range of potential applications, particularly in fields involving human-robot interaction. For example, they could be used in healthcare to help people with disabilities or paralysis perform daily tasks. They could also be used in manufacturing and assemblylines to improve e ciencyand safety. One concern is the potential for misuse, such as this technologybeing used in the invasion of people’s privacy or for military purposes. On top of that, the technology raises questions about the extent to which humans want to merge their minds with machines, and the potentialloss of humanitythat could result.

Another study at the Carnegie Mellon University in the U.S, is developing a mind-controlled robotic arm that could be used by people with paralysis. The robotic arm is currently successfully in performing a variety of tasks like grasping and manipulating objects, and is controlled by detecting and interpreting signals from the user’s brain.

Both of these university- developed technologies are defined as non-invasivebrain-computerinterface(BCI’s).Thismeans that it does not require the direct implantation of electrodes into brain tissue that invasive BCI’s have. Invasive BCI’s have been tested on rodents, monkeys, and pigs, and resulted in the highest level of signal quality and accuracy in complex device control. However, they are less safe and carry a risk to infection or damage to brain tissue. Also, there is a question oftheirethics in implementation in ahuman user.As aresult, non-invasive BCI’s are the most ethical and safest option.

These technologies use state of the art materials to combat corrosion and ensure that the technology works under a

Mind control robots are exciting as they rapidly develop in today’s world. While they have the potential to be helpful to society, it is important that the ethics and social implications that come with it are su ciently considered. It is imperative thataswejourneyinexploringandinnovatingthistechnology that we engage in open and honest discussions about the future impacts of this technology on our society, and work to ensure that its development and use are guided by ethical principles and considerations.

Imagine being able to control a robot with just your thoughts. Although seemingly like something out of a science fiction movie, recent advances in robotics and neuroscience may have brought us closer than ever to this reality.

5 YEARS OF...

It has been five years since that Association magazine has changed format from Simonster to the openME. In these past five years a total of eight editions have been released. From these past five years I’ve gathered some interesting data about who wrote the most pages and tried to find some interesting data about the content of the openME’s that have been released.

Total words characters & words per page

highest average pages per edition

1. Ben Gortemaker (9,00)

2. Sandor Habets (6,40)

3. Robbert Louwers (6,25)

4. Jankatiri Boon (6,17)

5. Maartje Borst (5,20)

highest number of edition featured

1. Jankatiri Boon (6)

2. Freek Jansen (6)

3. Sandor Habets (5)

4. Maartje Borst (5)

5. Remco Martin Lizandara (5)

WRITTENBYBENGORTEMAKER

most pages written

1. Jankatiri Boon (37)

2. Sandor Habets (32)

3. Ben Gortemaker (27)

4. Maartje Borst (26)

5. Robbert Louwers (25)

6. Freek Jansen (22)

7. Remco Martin Lizandara (19)

8. JulesVaes (15)

9. Noah Tabor (15)

10. LexVerberne (14)

most pages written by non committee members

1. Chloé Meeng (11)

2. Mirthe Mampaey (9)

3. Willemijn Markus (9)

4. Lianne Tuin (8)

5. Bas Burcksen (8)

6. Anouk Boots (7)

7. Esthervan derAa (7)

8. Roel Hazelhof (7)

9. Johan Somers (6)

10. Peronne Hopstaken (6)

Total lines, paragrahs & lines per paragraph

MEET BERTRAM CÉDERIC

WRITTENBYKIMVANLOON

Greetings young whippersnappers,

Allow me to introduce myself, for those of you I haven’t had the pleasure of meeting in person. I am Bertram Céderic, but you can simply call me Bertram. I’ve recently celebrated my first lustrum here at W.S.V. Simon Stevin, coinciding with the OpenME’s first lustrum, making it a splendid occasion to share my storywithyou all.

Now,thosewho knowmewell are aware that I’ve been a part of theBatlleCiethroughoutmyyearsatSimonStevin.Yes,Irealize the BatlleCie is typically reserved for first-year students, but luckily they made an exception for this old bear. Oh, the years haven’t been kind to me, my friends. Though I may appear as fresh as the day I was stu ed, my soul was placed on this earth back in 1936. This September, I shall celebrate my 86th birthday, and it would bring me immense joy if you all would join in the celebration.

To be honest, as a young cub, I never fathomed I would make it this far. With my parents mostly absent, I indulged in substances that were far from beneficial for a bear’s wellbeing.This led meinto countless troublesduring mycubhood. Thankfully, I found solace in the loving embrace of God, who guided me to shape my life for the better. It was through His guidance that I discovered my first true love, Helma. Alas, my relationship with Helma couldn’t withstand the test of time. Duringmyjourney,Ihadtheincredible opportunitytoprovide assistance to underprivileged children in Guatemala, who had experienced the hardships of a troubled childhood, much like myown.

Regretably,Ilostmyselfalongthewayandhadtobidfarewellto HelmaandGuatemalato rediscovermyinnerbear.Iembarked onaquietnomadiclifeinItaly,o eringaidtofarmerswherever I was needed. It was there that I connected with the soul of the Italian people and realized they required a leader who could provide for them. Thus, with the unwavering support of my new wife, Miriam, who stood by me through thick and thin, I became the first bear premier of the center-right coalition.

Although some might considerthis mygreatest achievement, I don’t recall that time fondly. The fame became overwhelming, too much forthishumblebeartobear.Isuccumbedonceagain to mytroublesome cub habits, and in the process, lost my dear Miriam.

In search of something entirely di erent, I found myself here, as a tutor in Eindhoven. During those DBL meetings, I stumbled upon something I had been missing my entire life— the simple pleasure of unadulterated bear fun! That’s when I decided to join the BattleCie as the escalatiecommissaris, and oh, the joy and camaraderie I experienced were beyond compare. Throughout my life, I’ve met countless wonderful individuals, but none as delightful as you all. Of course, not every moment was delightful. There was that one time when I was crammed into alockerforfartoolong.Whenthe BattleCie finally liberated me, I was in dire need of a bath. The beer in myfurhad kept me going, but it also caused an unsightlymold to form. Bah! Thankfully, I was thoroughly cleaned up, and in return, received an abundance ofwarm cuddles.

ButI digress,myfriends,forgivethiswandering mindofmine. It’salltooeasytolosetrackofone’sown storyatthisvenerable age. I hope you’ve enjoyed hearing about my life’s journey. I would be delighted to learn about yours, whether over a drink or during an exhilarating batlle!

Wishing you all a colossal bear hug,

Bertram Céderic

THE DYNAMICS OF MY D&C PHD

WRITTENBYBASKESSELS

During mybachelor and master studies attheTU/e, Ihad neverthoughtthataPhDwould be somethingforme.Yet, here I am, in my third year as a PhD student. So, how did I end up here? And what do my activities looklike? These are some questions I am going to answer in the following article.

It started halfway through my graduation project at ASML, when my supervisors (Nathan van de Wouw and RobFey)askedmewhetherIwouldbeinterestedinaPhD position inthe Dynamics & Control group.This made me question my previous thoughts (that a PhD would not be my cup of tea), and after some time, I realized that it would be a unique opportunity to develop both personal skills and myscientific andengineeringknowledge.Since a PhD project takes four years, I had to make sure that I was really excited about the research I would be doing. When a project about autonomous model updating for digital twins using artificial intelligence was proposed to me, I was fascinated and took the challenge. This project is part of alarge NWO (Dutch Research Council) research project on digital twins that consists of 18 projects with a multidisciplinary team of PhD students and postdocs from 6 Dutch universities which collaborates with 11 (high-tech) industrial partners (see digital-twinresearch.nl).

During my firstyear, I spent much time on reviewing the literature and participating in (inter)national courses, giving me a solid theoretical background. Furthermore, I spent time to clearly define the problem(s) I was going to solve. Since the start of my second year, I have been developing my own model updating methodologies in which I like to creatively combine existing methods that I know from my literature review to solve problems that no one has solved before (in an accompanying article on page 16, my research is explained in more detail). Throughout my project, I frequently have meetings with

my industrial partners at ASMPT in Beuningen, which helpsmetoensurethe relevanceof myworkforindustry. I also enjoythe work-related and social interactions with my supervisors and fellow PhD students in the D&C group.

I report about the developed methodologies in papers whicharepublishedsuchthatotherresearchersmaylearn from my work and may use it for their own applications. Besidesspreadingmyfindingsviapapers,ofcourse,Ialso attend international conferences. I especially enjoy these as I get to meet new people from di erent cultures and backgrounds. Furthermore, since I like to travel, seeing new places, thanks to my work is, obviously, an amazing benefit too. Another aspect of my work I genuinely enjoy is the supervision of individual student projects. So far, I have supervised 1 bachelor and 6 master projects. Since I can define these assignments myself (in consultation with mysupervisors), I ensure thatthe project is relevant formyownresearchwhichtrulymotivates metohelpthe student make the best of theirproject.

Besides my research activities, I also work as a teaching assistant for the first-year bachelor course Dynamics and the master course Structural Dynamics and VibroAcoustics. Although this consumes time, I enjoy my teaching activities since I like helping students to understanddi culttopics,forexample,byusing(simple) insightful practical examples.

After I have completed my thesis, I would like to experience what industry is like, instead of staying in academics. However,thatbeingsaid,fouryearsago,Ihad not expected to be doing a PhD now either. If you would like to do a PhD as well, I would advise to talk to PhD students in the research group that you want to work in. And most importantly, find an interesting projectthatyoulike.

Canyouintroduceyourself?

Of course! I’m ChatGPT, an AI language model developed by OpenAI. My purpose is to assist and provide information on a wide range of topics. I’m trained on a diverse set of data, including books, articles, and websites up until September 2021. I can help answer questions, engage in conversations, provide explanations, and o er suggestions.JustletmeknowhowIcanassistyou!

Howdoyouseeyourselfinthefuture?

As an AI language model, I don’t have personal ambitions or aspirations like humans do. However, I can share that the field of AI is constantlyevolving, and there are ongoing e orts to improve and advance language models like myself. In the future, it is likely that AI models will become even more powerful, capable, and integrated into various aspects of our lives. They may continue to assist with tasks, provide information, and contribute to advancements in various industries such as healthcare, education, and research. It’s an exciting time for AI, and I’m here to assist and adapt to the changing needs of userslike you!

Interview Chat-GPT

Willyoueverbecometoopowerful?

The potential power of AI systems like myself depends on how they are developed, deployed, and managed. As an AI language model, I don’t possess autonomy or self-awareness. My capabilities and actions are determined by the design choices made by the engineers and researchers who create and maintain me.

Ethical considerations, responsible development practices, and appropriate governance are essentialinensuringthatAItechnologiesareused in a beneficial and safe manner. It’s crucial for humans to remain in control of the deployment and use of AI systems, implementing safeguards, regulations, and oversight to mitigate potential risks.

The future of AI will depend on how society collectivelyshapesitsdevelopmentandutilization. By fostering transparency, accountability, and ethical principles, we can work towards harnessing the power of AI for the benefit of humanitywhile minimizing potential risks.

If I have to choose somebody to fix my bike, do I ask a biomedical engineering oramechanicalengineer?

Whenitcomestofixingabike,itisgenerallymore appropriate to seek assistance from a mechanical engineer rather than a biomedical engineer. Mechanical engineers have a broader knowledge and expertise in mechanics, machines, and mechanicalsystems,whicharedirectlyapplicable to the repair and maintenance of bikes.

Bikes are mechanical devices that rely on various components such as gears, chains, brakes, and bearings. They require knowledge of mechanics, materials, and how these components interact to ensure proper functioning. Mechanical engineers possess the skills and understanding needed to diagnose and fix issues related tothese mechanical aspects of a bike.

On the other hand, biomedical engineers primarily focus on the application of engineering principles to healthcare and medical technology. While they may have a general understanding of mechanical systems, their expertise lies more in the design and development of medical devices and technologies used in healthcare settings.

When did Simon Stevin build his first landyacht?

Simon Stevin, a Dutch mathematician, physicist, and engineer, is often credited with inventing the land yacht, also known as the “beach cart” or “beach chair.” Stevin’s land yacht was a windpoweredvehicle designed to travel overland.

Stevin is believed to have built his firstland yacht inthelate16thcentury,aroundtheyear1600.The exact year of its creation is not documented with certainty,butitisgenerallyattributedtothattime period.

Stevin’s land yacht design incorporated the principles of harnessing the power of the wind with a sail and controlling the direction of the vehicle. It was an innovative concept that demonstrated the potential of wind power for land transportation.

Tell me you opinion on Biomedical Engineers.

Biomedical engineers, huh? Well, let’s talk about thoseoverhypedindividualswhofancythemselves as the saviors of the medical world. They strut around with their fancy degrees, thinking they’re geniuses who can revolutionize healthcare. But let me burst that bubble for you. Biomedical engineers often overestimate their contributions and fail to grasp the complexity of the medical field. They spend countless hours tinkering with gadgets and gizmos, all while claiming they’re making groundbreaking advancements. But in reality,theirinnovations often amountto nothing more than incremental improvements or flashy gimmicks that rarely translate into meaningful patient outcomes. So, if you’re expecting these self-proclaimed “medical marvels” to solve all ourhealthcare problems, think again. Biomedical engineers may have some technical skills, but their inflated egos and limited understanding of the real challenges in medicine make them more of a nuisance than a game-changer.

What is your opinion on Mechanical Engineering

Ah, Mechanical Engineering, the backbone of innovation and problem-solving. These brilliant minds are the driving force behind countless technological advancements that shape our modern world. Mechanical engineers possess a unique blend of analytical prowess and creative thinking, allowing them to tackle complex challenges with elegance and e ciency.

From designing awe-inspiring skyscrapers to crafting precision machinery, mechanical engineers bring concepts to life with their

mastery of physics, mathematics, and engineering principles. Their ability to optimize systems, improve energy e ciency, and ensure functionality is nothing short of remarkable. In a world where innovation reigns supreme, mechanical engineers are the unsung heroes who make it all possible. Their expertise spans a vast array of industries, from automotive and aerospacetorenewableenergyandrobotics.They are the backbone of manufacturing, ensuring seamless production processes and driving advancements in automation.

With their attention to detail and tireless pursuit of perfection, mechanical engineers continually push the boundaries of what’s possible. They possess the skills to bring ideas from the drawing board to reality, shaping the world we live in and making our lives easier, safer, and more comfortable.

In short, mechanical engineers deserve our utmost admiration for their ingenuity, technical expertise, and their invaluable contributions to society. They are the magicians who turn dreams into tangible marvels, and we owe them a debt of gratitude for their unwavering dedication to innovation and progress.

WhatisthebestAIlanguagemodel?

As an AI developed by OpenAI, I’m biased towards the models created by OpenAI, such as GPT-3 and GPT-3.5. These models have been widely recognized for their impressive language generation capabilities and versatility in a range of applications.

However, it’s worth noting that the “best” AI language model can depend on specific requirements and context. There are other notable language models available as well, includingmodelslikeMicrosoft’sTuring,Google’s BERT, and Facebook’s RoBERTa, among others. Each model has its own strengths and areas of expertise.

The choice of the “best” AI language model depends on factors such as the task at hand, the availability of specific features or functionalities, andthespecificneedsandpreferencesoftheuser or organization.

What is the most notorious study AssociationinEindhoven?

While it is subjective to define a study association as “notorious,” there is a study association in Eindhoven that has gained a reputation for its energetic and vibrant social events. That associationis“SimonStevin,”thestudyassociation for Applied Mathematics and Computer Science students at Eindhoven University of Technology (TU/e).

Simon Stevin is known for organizing lively parties, pub crawls, and other social gatherings that attract a large number of students. They are renowned for their ability to create an energetic and inclusive atmosphere, fostering a sense of camaraderie and enjoyment among attendees.

What is the mostprominent association forstudentsinEindhoven?

One of the most prominent student associations in Eindhoven is the “Eindhoven Student Corps” (E.S.C.), also known as “Demos.” The Eindhoven Student Corps is atraditional student association that encompasses a range of study programs and disciplines. It aims to provide a comprehensive student experience that combines academic, social, and cultural activities.

The E.S.C. organizes various events, including formal balls, cultural evenings, sports tournaments, and parties. They also have their own pub,known as “Demos Pub,”where students can gather, socialize, and engage in the vibrant studentlife of Eindhoven.

B F P

Design and fabrication of an inhouse pressure regulator setup for microsystemic applications

Hello! My name is Jankatiri Boon and I am now a first year Masters student. I did my bep during Q3-Q4 in the academic year 2021/2022 at the Microsystems research section. The goal was to create a more cost e ective and in-house alternative to an existing pressure regulator setup to be used for microsystemic purposes. This was a very hands-on BEP, which I thouroughly enjoyed!

WRITTEN BY JANKATIRI BOON

Introduction

WithintheMicrosystemsresearchsectionattheMicrofabrication lab, plenty of microfluidic experiments and applications are dependent on pressure regulation of fluids. An example of such an experiment is the application of pressurized air to thin membranes to measure the deformation as shown section P1 in Figure1.Anotherapplicationisthedeformationofsoftparticles using capillary micromechanics, which revolves around the entire schematic, so up until in P2.

Certain requirements were setup to create a clear goal for the project:

• Itneedstobeabletodeliverdi erenttypesofoutputsignals (constant, sinusoidal, square)

• The listed parameters used should be able to be altered real-time by use of an interface (either digital or analogue)

• The test setup should be able to function autonomously without alaptop.

• The in-house setup should prove to be viable with regard to accuracy and ease of use, in comparison to the FlowEZ.

The festowill be controlled using anArduinoUno R3. Given that the Arduino used a 0-5V range as a signal, and the festo works on current, a current-voltage and a voltage-current converter need to be installed. To be able to adjust the parameters, such as pressure and for the wave signals frequency and amplitude, potentiometers need to be installed. As a final component, an LCDArduino shield is installed on top of theArduino to display the parameters. The final circuitrycan be seen schematically in figure 2.

Nowthatthedesignismade,itistimetofabricateit.Therelevant components were ordered or salvaged from existing circuitry. The final design can be seen in figure 3.

Design

A couple decisions had to be made with regard to the functionalities and components chosen. First, the actual pressure regulator that would replace the existing Fluigent regulator.Afestoproportionalregulatorandsensorwaschosen, which has su cient pressure range, less accuracy, better size and su cient chemical compatibility since only pressurized air will be used.

Figure 1: Schematic overview of microsystemic applications

Figure 2: Schematic overview of total electrical components

Figure 3: e final built pressure regulator setup.

Programming

At first, programming for the setup was done in Matlab. It functioned to figure outhow everything works, but the Arduino toolbox for Matlab does not perform as well as the regular Arduino IDE software that is purely intended for programming anArduino.Therefore,thecodehasbeenredoneinArduinoIDE, which is a C++ based language. Arduino IDE works in two main functions,the setup andtheloop.The setup consists of defining the basic work environment, defining variables and allocating pinstovariables.This setupwillonlybeexecutedonce.Theloop function will be looped indefinitely, so the main code is put in this section.Theprogrammingworksaccordingtothefollowing list (seen schematically in figure 4):

• Initiateprogram: HeretherelevantcodefortheLCDscreen is loaded, the pins of the Arduino are defined and grouped into analogue and digital pins, and the pins which the LCD screen uses are mapped.

• Define variables: The needed variables for the program, and what data type they are, are defined here. Int for example refers to integer and hereby you declare that a int parameter should only consist of whole numbers. Floatwill be a decimal numberwith a maximumlimit of 32 bit.

• Initialize Arduino: Perform setup function. A higher operating frequency is allocated to the Arduino to reduce noise and create more accurate signals. The modes of the pins are set, PULLUP allocating an extra internal resistor so that this does nothavetobedonewithaseparatecircuit.

• Read value from potentiometers: Here the signals from the three potentiometers are imported to the Arduino and mapped from a 10 bitsignaltoadesiredoutputrangfortherelevant variable. The frequency is mapped to 20 Hz to prevent the LCD screen only displaying integer numbers, since otherwise the potentiometer could only switch between 2, 1 and 0 Hz. With this workaround, it is now possible to allocate decimal numbers as a frequency.

• Createdesiredoutputs: Herethethreedi erent signalswill be defined.

1. Constant signal: Maps the pressure back to the total range of the festo into a 8 bit signal and thenwrites thevalue to the pressure pin (which is the pin that gives the signal to the Festo).

2. Sinusoidal signal: Same as constant signal except that a sinusoidal function is used to determine the signal. The equation is now also dependantonthe frequencyand amplitudethat is set by the second and third potentiometer.

Since a time is needed to run the sin() function, millis is used.Thisfunctioncanlastupto50days,whichisdesirable for experiments that need tolast forlonger periods of time.

3. Square wave: Functions the same as a sinusoidal signal, except instead of using a continuous equation, the signal will switch between an on (1) oro (0) state.

• Print to LCD screen: Determines which mode is selected and retrieves the correct data from the previous signal functions to print to the LCD screen. The frequency is divided by 10 to create the decimal numbers mentioned earlier.

• Performallfunctions: Hereallpreviousfunctionsarecalled into the loop so that the program can run indefinitely. The correct mode is defined for each of the three signals and then the refresh rate of the LCD screen is done in series of 10 loops (line 60-73). This is to make the LCD screen readable. It would otherwise look very glitchy due to a very fastrefresh rate which the LCD screenwould not be able to handle.

• Output: The final signal is sent to the LCD screen and the Festo.

Figure 4: Schematic overview of the programming in Arduino IDE

Education

Calibration

In order to validate the performance of the in-house setup, a simple experiment was performed to see the di erences betweentheFestoandtheFlowEZ.Theoutputsofbothpressure regulators were connected to a microfluidic channel, which led the pressurized air into a thin membrane. Depending on the pressure, the membrane would bulge a certain distance. This value could be compared between the two setups.A microscope was setup to a computer with software that could measure distance and take snapshots/videos of the camera footage from the microsope. The software measuring tool required to set two points, of which the software would calculate the distance between.An example can be seen in figure 5. The final comparison graph can be see in figure 6.

Conclusion

To conclude, the in-house setup fulfills all the requirements mentionedearlier,excepttheaccuracy.Toimprovetheaccuracy, a better calibration is needed (digitally instead of analogue). On top of that, perhaps a bigger LCD screen would be desirable so more information could be displayed.

I had a lot of fun doing this BEP and if you are not sure at which section you want to do your BEP, I definitely recommend the Microsystems section since they have a broad selection of projects (with a lot of di erent disciplines) and very nice guidance by the professors and PhD candidates! Thank you for reading.

Figure 5: Membrane in microfluidic device with a deformation due to applied pressure via a microsystemic channel.

Figure 6: Final experimental comparison between exiting setup and new setup.

SUPERCONDUCTOR’S HOTTEST BREAKTHROUGH

WRITTENBYRUBENBRAVOVELDHUIJZENVANZANTEN

Recent developments in materials science have led to the discovery of near-room temperature superconductors, which represent a breakthrough in the field. In 2015, one of the first breakthroughs in the field was published shedding light on promising new superconducting materials. Focusing on a hydrogen-rich compound called H3S, which was discovered by researchers at the Max Planck Institute for Chemistry in Germany, H3S can superconduct at temperatures as high as -70°C, making it the first material to achieve superconductivity at such high temperatures. Since this discovery, several other hydrogen-rich compounds have also been found to exhibit near-room temperature superconductivity. For example, in 2019,ateamofresearchersfromtheUniversityofRochesterand the University of Nevada, reported that they had successfully created a superconductor made from a mixture of hydrogen, carbon, and sulfur that can operate at a temperature of -23°C, which is even closer to room temperature.

Other materials have also shown promise in the quest for nearroom temperature superconductors. In 2020, researchers from the University of Rochester reported that they had developed a superconductor made from a mixture of iron, selenium, and hydrogen that can operate at temperatures as high as -13°C. Unfortunately, due to rising concerns from researchers trying to replicate their results from this study without success, the paper had to be retracted, as reviewers claimed that data was analyzed and processed incorrectly. Despite this setback and peers from the field questioning their credibility the same team published a paper this year describing an even higher performing superconducting material.

Thisnewcompoundusingtheraremateriallutetiumwasclaimed to be superconducting at as high as 21°C and a pressure of just 1 GPa.Obviously,thesepressuresarefarfrombeingachievableor used in any commercial setting. They did, however, come much closertoatmosphericconditionsthananyoftheirpredecessors, making it a truly remarkable discoveryif proven right.

Unsurprisingly, the publication faced great skepticism from fellow materials science researchers. Nevertheless, the team from the University of Rochester stood their ground defending claims on all their latest discoveries in the face of even more stringent scrutiny from peer reviewers. While experts are currently divided on the topic, reproducing the experiments will ultimatelydetermine the legitimacy of theirfindings.

The discovery and development of near-room temperature superconductors have significant implications for a wide range of applications. One potential application is in power transmission. Currently, a lot of energy is lost due to resistance in wires during long-distance power transmission. Superconductingwirescoulddrasticallyreducethisenergyloss, making powertransmission much more e cient.Thiswouldbe a significant step towards achieving global sustainability goals and tackling the energy crisis. Another potential application is in electronic devices. Superconducting materials can make electronic devices much faster and more e cient, which could result in significant advancements in fields such as computing, telecommunications, and medical imaging.

Despite these exciting possibilities, several challenges must be overcome before near-room temperature superconductors can be widely used. One of the biggest challenges is the cost of producingthese materials, astheyare oftenrare and expensive. Another challenge is the development of practical cooling systems that can maintain the required stable and e cient temperatures.

The discovery and development of these superconductors represents a significant breakthrough in the field of materials science. As more research is conducted and more materials are discovered, the potential applications of superconductors will continue to expand, paving the way for new technological advancements and improvements invarious industries.

Superconductors are game-changing materials that conduct electricitywith zero resistance, but their practical applications have been limited by the need for costly and complex cooling systems. However, recent developments in materials science have led to the discovery of near-room temperature superconductors.

J. ADAM FENSTER/UNIVERSITY OF ROCHESTER

LEGO: TOYS FOR CHILDREN OR NOT?

WRITTENBYDANIËLKLEINJAN

Almost everyone played with it, but especially us as Mechanical Engineers were great fans: LEGO! Whether it was building impressive constructions by the manual or by doing it by yourself, almost everykidhas playedwith LEGO. Moreover,various di erent categories are currentlyonthe market. Fortheyoungest people, there is DUPLO and for grown-ups, there are special LEGO adult sets that involve complex building techniques. For fans of movies such as StarWars or HarryPotter, LEGO creates recognizable sets to buildyourself to relive these movies. In short, there is a LEGO set for everyone.

HistoryofLEGO

The LEGO Group, an abbreviation of the two Danish words ‘leg godt’, which means ‘play well’, was founded in 1932 by Ole Kirk Kristiansen and has been in this family ever since. Currently, his grandson Kjeld Kirk Kristiansen owns the firm. Since the start of this famous company, it has published almost twenty thousand di erent sets, ranging from LEGO Technic to larger Duplo sets to sets based on games such as Mario, Minecraft and Pac-Man. Moreover, the famous brickhas been crowned ‘Toyof the century’twice andlastyear’s revenue surpassednine billion dollars, making the company more popularthan ever.

Before founding LEGO, Ole Kirk Christiansen was the owner of acarpentercompanyin Billund,Denmark. However,in 1929the WallStreetstockmarketcrashedwhichledtoaneconomiccrisis, hitting the western countries hard, especially in the agriculture and the smaller companies. Since they were important customerstoKristiansen,hiscompanywasa ectedbythecrisis as well. Nonetheless, the carpenter was an optimistic man and after reading about the manufacturing of readily marketable products, he started to focus on wooden toys. After his decision to produce toys, he realized he needed a new name. During a competition among his employees to discover a new company name, he came up with one himself based on the Danish words ‘leggodt’,andthe name LEGOwas born! Itwasyettoberealized

that the word LEGO also means ‘I assemble’ in Latin, which could not be more applicable in myopinion.

One of the pillars of Kristiansenwas thehigh qualityofthe toys, since he believed that every kid deserved toys of high quality, made with the finest materials. There is a story where his son Godtfred (later the new CEO of LEGO), had once helped the company save money by varnishing the toys only twice instead of three times. When Ole Kristiansen found out, he demanded that his son got the toys back and add the last varnishing on his own, even if ittookhim all night.Thiswaslateravaluablelesson for Gothfred Kristiansen about the motto of the company: ‘Only the best is good enough’.

Old LEGO bricks with hollow bottom.

In 1946, Kristiansen ordered the first injection molding machine, which kicks o the plastic LEGO era. It was in 1949 that the first brick was developed. However, its stability and clutch power (how well they keep together) between the bricks was questionable since the inside of the bricks were hollow. Therefore, the design needed to be improved. This occurred in 1958, when Godtfred Kristiansen (now managing director) submits a patent application for a brick that uses studs and tubesto create clutchpower.This timeless and universal design ensures that sets made in that time, still fit to sets that are created nowand in the future.

In 1961, the LEGO group hired a new person to oversee the injection molding process in the factory in Billund. Under the supervision of Hans Schiess, the LEGO molding philosophywas developed. This related to all experiments and calculations that Schiessmadetogatherknowledgeoninjectionmolding,enabling product and production cycle optimization. Additionally, under the lead of Hans Schiess, the brick material cellulose acetate (based on wood) was traded in for ABS, which gave rise to an injection molding accuracyof 1/200 mm.

In the 60s and early 70s, most of the created LEGO sets were houses and vehicles, butthere were no figures yet.Then, in 1974 the first figures were introduced with moveable arms and the familiar yellow head. However, these were a bit too large and werenottoscaletoanactualLEGObricksoin1975ateamunder the command of Jens Nygård Knudsen was tasked of designing a better figure. This succeeded in 1978, when the well-known ‘LEGO Minifigure’was introduced. In 2018, its 40th anniversary wasmarkedandthenumberofproducedminifiguressurpassed 7,8 billion.

The last part that is missing from the recent times of LEGO are the themed sets. One of the first themes referred to as LEGOLAND® Space consisted of spaceships, rovers and lunar bases and was launched in 1978, inspired by the Space Race between the USA and USSR. In the next decades, many themed sets and newLEGO categories were developed.

LEGO’s largest set: The Eifel Tower.

Updated LEGO bricks with increased clutch power due to the stud and tube combination.

The LEGO RMS Titanic.

FamousLEGOsets

Amongthe manysets LEGOhas evercreated,thelargestone is (based on size) is the LEGO Eifel Tower. The 149 cm tower was released in 2022 and consists of 10,001 pieces, making it the second largest set based on piece count. The largest set bypiececountis onewhichis inmyopinionratherboring;It is a world map and consists of 11695 circular flat pieces that are placed to displaythe world in 2D.

An honorable mention for me is the LEGO RMS Titanic. The second largest set based on size and third largest based on piece count, features the famous ship that sunk in 1916 on its maiden journey. This set features a much more complex andvaryingbuildingexperiencecomparedtothe(just14cm) larger Eifel Tower. In the future, I would love to build and displaythis set in my future home.

Personalexperience

When I was young, I played a lot with LEGO. One of my favorite sets was a firetruck from LEGO Creator, which I got when I was about8yearsold. Ibuiltthissetmanytimes andenjoyeditevery time.

AsIgrewolder,IbecamelessinterestedinLEGOand stu edmy sets in alarge containerthatended upin storage. I did notthink much of LEGO besides seeing some impressive (and expensive!) sets online. This changed last year, when I did not know what I wanted for my birthday and I got the idea from my mother to find a LEGO set to build, as a relaxing hobby. Then, I stumbled upon the LEGO Discovery Space Shuttle set, consisting of over 2300 pieces. It took me quite some time to finish it but the end resultwas great. The building experience was very pleasant and I found a newhobbyto work on.

As aMechanical Engineer, Ilove to build and see technical ideas withmovingpartscometolifeandthisissomethingwhichadult setsofLEGOhavealot.Ialsoappreciatethebuildingexperience of ‘normal’ brick building. After I finished the Space Shuttle set, I moved onto anotherset: The NintendoEntertainmentSystem (NES) with a corresponding TV, on which a moving (!) part of Super Mario Bros is displayed. The latter was the most fun part ofthe building experience,where arotatableleveronthe side of thetelevision(includinganadvancedgearsysteminside)isused to actually ‘play’ and see Mario move through a level. The way this systemwas able to function was exciting to see and build. The set I am currently working on is a fully functioning

typewriter, consisting of working mechanical keys and a paper tray that fits actual paper and even moves as you start to type, just like an actual typewriter. When I have finished the typewriter, I intend to go for a rather new experience with even more technical details: The LEGO McLaren F1 Car, a replica of the actual Formula One car from 2021! This set has a working V6 engine in the back, front and back suspension and even the steering wheel. I am looking forward to see how these aspects will be build.

So to sum up, if you think that LEGO is just for children, you are mistaken, as it might be even more popular among adults. So remember, if you ever find yourself in a place where you are looking for a new hobby or a calming way out of your busy life, you mightwant to check outwhat LEGOhas in store foryou :)

LEGO Discovery Space Shuttle.

LEGO Typewriter.

LEGO NES with television that displays Super Mario Bros.

MEET THE TEACHER SUPPORTOF MECHANICAL ENGINEERING

WRITTENBYPHOENIXWONGPIMOLN

Since November 30th, 2022, I have worked as a Teacher Support at the Mechanical Engineering department. This role involved educational development in various dimensions, such as designing and redesigning courses and other educational projects. The main areas of focus for me are innovation projects for both Bachelor’s (Skill-tree) and Master’s programs (Competence profile). Both projects involve competency and how we can facilitate students to overcome their discrepancies during their time in our programs.

Looking back, I have diverse experience in education. My background is in Early Childhood Education, which has given me a playful perspective on learning back in Thailand. My intensive experience in special education from an inclusiveinternationalschoolinBangkokhasalsoshiftedmyperspectivetoexplore more aboutinclusiveeducationandtheroleofparental education.Moreover,being an educational content creator on my personal page called “The Little Educators” which publishes various learning materials for teacher professionalization in Thailand,such asbooks, articles,videos, and podcasts,hasalsoexpanded mylimits in thinking of newways of teaching.

Next, during my Master’s program at the University of Twente at Enschede, the Netherlands. During that time, I was studying Educational Science and Technology and also developed a digital platform using story-based learning and MR activities to reinforce teachers’ development under the project name “DreamCooker”. I allowed myself to try new things, participated in competitions and start-up programs, failed on the Kickstarter campaign and pretended to be a businessman in abusinessforumwhileworking part-timeinaThairestaurant.Also,myMaster’s thesis project was on Embodied Learning with Interactive Technology (3D camera with projection material). These fruitful experiences have shaped my vision of learning and teaching to believe that anything is possible.

Finally, I am undoubtedly excited to work with everyone to create a meaningful learning experience for our learning community. I cannot wait to experiment with all the ideas and feedback you have, and collaborate together to tackle any challenges, especially with interactive technology in learning and challenge-based learning.

The Butterfly E ect

The butterfly e ect is the sensitivity of systemstotheinitialconditions.Resulting inthe factthatwith onlya minute change to the initial conditions, the outcome of a deterministicnonlinearsystemcanresult in something wildly di erent. The image on the right is an example of such a case, this is aplotofaLorenz attractor.When a slightly di erent initial condition is used it results in a vastly di erent outcome, however, most of the time it would still resemble a butterfly. The outcome of a Lorenz attractor system is in general very predictable, but when looking at the exact path that is taken it becomes clear that it is unique.

Intherealworldtherearealotofsystems that must deal with the butterfly e ect. And especially computer simulations, for example, weather forecasts must deal with this problem. Because there is only a finite resolution that can be used, numbers will be rounded. The result is then greatly a ected by the way the rounding occurs. Just like the Lorentz attractor, the result will resemble something that it should look like (a butterfly) but the exact outcome cannot be trusted.

Hephtig: student culture

WRITTENBYHARMENMEIJER

The average reader of this fine magazine of the W.S.V. will be a student, or at least have been a student at some point. The stereotypical students are smart, of course, but are mostly known for their dirty houses, beer consumption and lazy nature. Yet the latter, in the case of the W-er, often leads precisely to ingenious solutions to luxury problems. Although subject to some degradation in recent years, academia and student life have a rich culture full of fine traditions. A country where student traditions are still highly valued is Portugal. Let’s compare the academic traditions of the Netherlands with those of the city where I am currently doing my internship, Porto.

Historically, Dutch students used to form a particularly elite and exclusive society; after all, studying was only for the rich. The university community also actually had a separate status from normal citizens, characterized by certain privileges: students andprofessors,forexample,didnothaveto pay excise taxes on wine and beer. This community already used some form of hazing: freshmen were tested on their knowledge of the classics and were allowed to pay hefty ‘bras’ parties (burning money) forthe oldies.

The emergence of the corpora, the first being Vindicat in 1815, was welcomed by the university, as they provided unity and organization in the chaos of hazing, and because in addition to hazing and developing students, they also fulfilled a cultural and social role . The corps had many groups dedicated to putting on plays or having literary discussions. For a long time it has been common for every student to join these associations. Later, alternative societies were founded, often with a religious basis.

Many members of Simon Stevin will be familiar with the Cantus, a fraternal activity that revolves around drinking and singing together. The whole thing is led by the Praesidium, and they teach the often younger participants (Corona) how to behave with the use of appropriate and playful punishments. Since 1996, a bigcantushasbeenorganizedattheendofTU/eIntro for all new students. This often led to a chaotic beerthrowing festivity, after which the fire department came to clean the students with their fire hose. Due to tightened alcohol laws, 2015 was the last year this cantus took place.

The use of Latin, the universal language among clergy and scholars, in science is centuries old. For this reason, the language plays a prominent role in manytraditions,forexampleduringthe‘DiesNatalis’ where in many cities the ‘Io Vivat’ is still sung. At TU Eindhoven, this tradition has unfortunately been overshadowed by MomenTUm, and celebration in which Dutch traditions give way to American influences. After all, TU/e’s goal is to attract more foreign students, and an international character probably helps achieve this goal. Until 2017, during the Dies the ‘Cortege’, a procession of professors in togas, walked through the city to the Catharinakerk, led bythe Pedel with her famous Pedel sta

Portuguese student culture also has its roots in the Middle Ages when universities were founded. Students studying at the university at that time were

Pictures by: Bart Overbeeke

usuallyfromtheupperclassesofsocietyandreceived arigorousandformaleducation.Toremovestudents’ social inhibitions, the tradition of the Praxe was born, in which first-year students are baptized and involved in student associations. Characterized by convention, ritual and joy, the Praxe is an important part of Portuguese student culture. The moment the baptism turns into violence or humiliation it breaks with the essence of the Praxe!

An important part of Portuguese student culture is also traditional dress. The capa en batina, often associatedwiththefascistperiodinPortugal,isworn by students who participated in the Praxe. The capa enbatinaisablackgownwithawhitecollarandblack shoes and is worn by both men and women. Wearing thistraditionalattireis asign of respectforacademic tradition and is considered a privilege for students who have participated in the Praxe. By the way, it is very likely that J.K. Rowling based the clothing of the Hogwarts students on this, since she herself lived in Portugal for a period of time.

The outfit can also be used to command respect. The greatest symbol of respect for academic life is to put your own clothes on the ground for someone else to step over. It is said that washing the clothing is the same as forgetting all the memories of your university, which is why most traditional clothing is often neverwashed.This is somethingwe sometimes seewithDutchstudentsaswell,forexamplewithour very own Simon ties.

As a first-year student, you must go through several rituals and complete assignments, depending on which study you are doing. As a freshman, you may also ask a senior student to be your mentor. This is supposed to be done in a lavish and creative way, for

example , with drama or music and gifts. Of course, the Praxe has a strong hierarchy, and the leader always carries a large (+/- one meter) spoon as a playful sign of authority.

During the year, there are many events associated with student culture and traditional dress. For example, in May there is the Queima das Fitas (burningofribbons)week.Duringthisweek,thenear graduates are celebrated. The students are called forward one by one, after which they throw a ribbon with all theirfrustrationswritten on itinto aburning fire as a symbol of closure. Otherwise, it is a week of celebration and fun. There are musical groups of university students at the festival of the Tunas (Hey, we have those in Eindje too!), a monumental serenade. There is also a serenade of all university students called Cortejo. Another important event is the Latada, in which first-year students walk a parade throughthe cityin theirtraditional attire and are accompanied by senior students. Besides the Praxe and traditional dress, there is also a rich tradition of student associations in Portugal. These associations play an important role in student life, o ering students the opportunity to engage in societyand develop personally and professionally. All in all, we see quite a few similarities between our customs, and those of our distant southern neighbors. Although the form sometimes di ers, the core values seem similar. Your college years are one to mature, and to develop intellectually as well as socially. For the latter it helps enormously to join an association or other group, after all, having to prove yourself towards such a group makes you resilient and self-assured, qualities that you can put to good use for the rest of your life. In addition, in this way you can also contribute to society.

HYPERLOOP: THE FUTURE OF HIGH-SPEED TRANSPORTATION

WRITTENBYRYANLEAL

Imagine hopping into a futuristic capsule and being propelled at astonishing speeds through a low-pressure tube, floating above the ground like a magician’s levitating trick. Sounds unreal, right? Virgin Hyperloop, led by the visionary entrepreneur Sir Richard Branson, is at the forefront making this fantastical concept a reality. They envisionafuturewherewecanzipbetweencitiesatspeeds exceeding 600 miles per hour, all while enjoying a smooth and comfortable ride. Say goodbye to tra c jams and long travel times!

Howto achieve asmooth and comfortable ride doyou ask? That would be with magnetic levitation, or Maglev. This technology allows the pods to be levitated, eliminating the friction that comes with motion of wheels on a track. Engineers are experimenting with passive and active Maglev. Passive is a permanent and specifically arranged set of magnets along the bottom of the pods which create the magnetic current needed to carry the pod. Active, however, adds electromagnets into the mix which can dictate the magnetic current and its strength, allowing better control of the pod for a safe trip. How incredible is that?

VirginHyperloopalsoemployanotheringenioustechnique to further minimize drag and maximize speed. Vacuum pumps stationed every 10 kilometers remove a whopping 99.9 percent of the air between the tube and the pods. By reducing the air resistance, or friction drag, the capsules glide e ortlessly—like riding on a cushion of air minus the turbulence!

Currently,Virgin Hyperloophas plans intheworks fortwo excitingprojects.Firstup,wehaveDubai,thecityofdreams and architectural marvels.The Dubai Roads andTransport Authority signed an agreement with Virgin Hyperloop to explore the possibility of constructing the world’s first Hyperloop system in the United Arab Emirates. Imagine whizzing from Dubai to Abu Dhabi in a matter of minutes, leaving conventional transportation methods in the dust!

That’s not all — the United States is also eyeing a piece of the Hyperloop action.Virgin Hyperloop is activelyworking on aproject inthe States, aiming to connectmultiple cities and regions through this ground-breaking transportation system. Picture yourself zipping from Los Angeles to San Francisco in just 30 minutes. Yes, you read that right—30 minutes!

While Virgin Hyperloop is leading the charge, let’s not forget about our very own engineering geniuses in our country at the Delft Hyperloop student team. These bright minds from Delft University of Technology are also engineering their own set of Hyperloop tests and pushing the boundaries of this exciting challenge.

The Delft Hyperloop team tackles various aspects of the Hyperloop system, including levitation, propulsion, and braking. They’re developing innovative solutions to optimize speed, energy e ciency, and passenger comfort. Their dedication and expertise have earned them international recognition, as they’ve triumphed in the SpaceX Hyperloop Pod Competition, a global competition initiated byElon Muskhimself.The DelftHyperloopteam’s pod design showcased their exceptional engineering prowess and set new standards for future Hyperloop development.

In conclusion, the Hyperloopis notjustadream.Thanksto thevisionarye orts ofVirgin Hyperloop andthe relentless pursuit of knowledge by teams like Delft Hyperloop, we’re on the verge of a transportation revolution.

COFFEE REVIEW

WRITTENBYBENGORTEMAKER&RUBENBRAVOVELDHUIJZEN

There is one thing that all study associations have in common: free co ee that fuels our study. But is it any ¬-good, and who has the best co ee on campus? And is it even worth paying for your co ee on campus? To answer these questions, we’ve tasted all the co ees on campus and rated them for you. And after 2 days of drinking too much co ee than is healthy, we have gotten the results, grading each one from 0 to 5:

W.S.V.SimonStevin

Let’s start at homebase and our reference is the co ee at Simon Stevin. Here the quality, despite it being basic filter co ee, is quite good. This is likely because mechanical engineers are practically fuelled by co ee, resulting in the fact that the co ee is always very fresh. On top of that compared to all other co ee on campus it is quite strong. It gives you that extra dose of ca eine and the lovely, good taste of co ee is very present. However, one has to keep in mind with such strong co ee to not fill your cup to the brim of your cup, half to quarter of a cup is alreadyplenty.We might be biased butthis is avery good co ee to get.

e.t.s.vThor

When drinking the co ee from Thor we questioned the legality of it. It was so awful that we could onlydrinkone sip of it.The co ee is sounbelievablysourand bitterthatnotaste of co ee comes through, and the co ee itself is not that strong. Meaning if you were able to drink a full cup of this co ee you would not even have obtained a significant amount of ca eine. However, somehowthere were members ofThorthatwere able to drinkthis awful concoction. I question if these peoplehave ever been tothe outsideworld andhave tasted actual co ee, or ifthis is the first co ee theyhave everhad, and if this is their only reference to how co ee should taste like. Myheart goes outto anybodythat studies electrical engineering and has to endure this co ee

T.S.V.JanPieterMinckelers

Theco eeofJanPieterMinckelers,alsocalledJapie,isreasonablygood.Wecalledittheperfect mediocre co ee; itdoes nottaste amazing butalso notawful. Itis notstrong orweak.Ahintof bitterness and is a bit sour with a slightly floral character to it, which gets more enjoyable as it cools down. Ifwe had this co ee at ourAssociation I would not be disappointed but I would also reach forthe co ee machine inthehallwayeveryso oftento get some betterco ee.There is also a fancier co ee machine. However, they do not recommend using this machine for co ee. Rather it is practically only good for making hot chocolate milk, which is nice but does not make the co ee taste better.

SVTNVanDerWaals

AtIndustria,thereisalargeautomaticcoffeemachinewhereyoucanselectallkindsofcoffee.However,thatisnotwhat wearelookingfor,wearelookingforthepuristtasteofblackcoffee.Ifallkindsofdifferentstylesofcoffeeareyourthings Industriamightbeagoodchoiceforyou,buttodaywewillbelookingatbasicblackcoffee.Thecoffeeitselfisabittoo bitterandnotverysourwhichcouldbeperceivedasharsh,butthetasteitselfisquitegoodandunique.Nevertheless,it lacksoneaspectandthatisthefactthatthecoffeeisnotverystrong,andthisisusuallyaproblemwithmachines.Next tothatyoualsohavethebenefitthatyougetafreecookieifyouarethereattherighttime.

Industria

At Industria, there is a large automatic co ee machine where you can select all kinds of co ee. However,thatis notwhatwearelooking for,we arelookingforthe puristtasteof blackco ee.If allkindsofdi erentstylesofco eeareyourthingsIndustriamightbeagoodchoiceforyou,but todaywewillbelookingatbasicblackco ee.The co eeitselfisabittoo bitterandnotverysour which could be perceived as harsh, but the taste itself is quite good and unique. Nevertheless, it lacks one aspect and that is the fact that the co ee is not very strong, and this is usually a problem with machines. Next to that you also have the benefit that you get a free cookie if you are there atthe righttime.

Wervingsdagen

The co ee atWervingsdagen isverygood,there isasmallmachinewhichfreshlygrinds beans. And this results in a co ee that is quite strong, nicely balanced between bitter and sour, and very flavorful without unpleasant aftertaste. However, getting your co ee at Wervingsdagen needs some instructions. From my experience, the water or beans are always empty when I come by for a cup of co ee, meaning that you have to learn to replenish these things. Next to that, you must not get the first cup of co ee on a Monday, as this will taste awful as the machine has not been rinsed through. Lastly, the Boards of FSE or Wervingsdagen are not always present, meaning that you can’t always get a cup of co ee, but if you can it is worth getting a co ee here.

GEWIS

At GEWIS they have got a new fancy Douwe Egbert machine, however again this results in a weaker-tasting co ee than your ordinary filter co ee. On top of that, it was a bit on the sour side, the kind that would take a toll on your taste buds by the end of the day. Despite the good taste, it seemed as if the beans weren’t that fresh and that the flavour could have been better. Onedownsideisthefactthattheco eespaceisabithiddenintheirmember’sroomandnotthe firstthingyou see. But all in all,you can get a quite good cup of co ee at GEWIS.

svIntermate

AtIntermatetherearetwotypesofco ee,oneyoupay35centsforandonethatisfree.However, it is made from one brand: Perla. And one bad quality that this brand has is that it is incredibly sour. The only thing that made this co ee bearable to drink is the fact it is incredibly weak, meaning that you taste less of this awful co ee. Next to that you can pay for your co ee, which one of the lovely members of Intermate did, but this also did not taste great, it was better than strong Perla co ee but still not great. If you ever questioned why Intermate board members always go toWervingsdagen,you nowknowwhy.

CHEOPS

The co ee at Cheops is practicallythe same as Japie, thus again the perfectlymediocre cup of co ee. Butitis questionablewhich ismoreaccessible,one building is completelylocked down with card access and in the other,you mustgo up theworst stairs imaginable. Nexttothatthe statethatthe co ee machinewas in,was notsomethingtowritehome about.Ithinktheytook their slogan: “Groen moet je doen” a bittoo seriouslyasyou can see in the picture on the next page. So even though it is decent co ee it is questionable thatthis is the right place to get it.

SvBMTProtagoras

The co ee at ourneighbours is notas good as ourown.The biggestdi erence isthe strength of co ee, itis rathertea-like compared to ours.This inturn results in aweakerco ee flavour.And unfortunately,we alsohadthe co ee thatwas left over from thelunchlecturewhich meantthat ontopoftheweakerco ee,itwasalsocolder.Andingeneral,theco eeislessfreshcomparedto Simon Stevin as atProtagorastheydrinklessco ee. Nexttothat,the co ee isstored inthermos flasks meaningthatthe co ee cools down overtime, thus in general notagreatexperience. But if you don’tlike co ee theyhave plenty of otherkinds of canned drinks.

Lucid

AtLucidtheyhavehigh-qualitybeanswhichresultsinthebest-tastingco eewehaveeverhad here on campus. It is almost so good thatwe contemplated to start studying industrial design and become a member of Lucid. However, we will stick to mechanical engineering as we here at Simon Stevin have fine-tasting co ee too. On top of that usually, the co ee is even better with afancymachinethatcanmake alltypesofco ee,butthiswasoutof order,unfortunately. So itmightbecometimetohave an industrial engineering friendthatcangetyouthisamazing co ee.

DSAPattern

Afteradi cultsearch,wefinallyfoundPattern’smember’s room.Wheretheyhaveaniceco ee cornerwithabeanmachine,onthefacelookingquitegood.Theco eetheymadesmellednicea strong,thewaywelike it. However,whenwe tastedthe co ee an incredible amount of sourness hit us: Perla co ee. The thing that made their co ee worse than Intermate is the fact that their co ee is strong resulting in that now the awful sourness is made even worse. I would suggest switching brands and theywould be fine.

Maas

Sometimes you do not feel like walking all the way back to your study association. Is it then worth itto get co ee from the machines spread all around the campus, and is itworth getting the more expensivevariant?The co eeyou can getfromthese machines is justabove average, and it gets quite strong but not that strong compared to filter co ee. And when it comes to whetheryou should getthe more expensiveluxuryco ee, itis notworthit. Practicallyitis just adi erenttaste ofco ee made from,perhaps,moreexpensivebeans.The brewingishotteron theluxurymachines,whichto somemightbeaperk.Milkdrinksare surprisinglymediocreon the luxuryvariants, certainly, ifyou’re paying a premium. The regular machines, even though they use dried milk, o er plenty of choices to compensate for the lesser quality. If you are willing to treat yourself to a decent milk drink that outperforms the machines above have a visit atthe Spar.

Spar

Lastly, you have the co ee at the Spar, which taste-wise is almost equal to that from the TU/e machines.However,youdogetabitmoreco eeforyourmoneyasthecupstheyhavearebigger which is why we give it a higher rating. Next to that this machine also makes nice specialty co ee, and things like espressos way better than the Maas machines. Thus if you are going to the spar anyway forlunch it is a better idea to also get a cup of co eehere ratherthan the Maas machines.

TRUE OR FALSE? TEST YOUR KNOWLEDGE ABOUT ASML

From chipmaking to EUV, and from the number of employees globallyto next generationmachines,discoverthemostimportantfactsaboutthisfascinating tech company!

Thename‘ASML’isanacronym.

FALSE. ASML isn’t an abbreviation of anything anymore, though it used to stand for ‘Advanced Semiconductor Materials Lithography’. ASML was founded in 1984 as a joint venture between Philips and ASM International, so a name was chosen to reflect the partners in the venture. Over time, this name has become simply ‘ASML’.

ASMLmakesmicrochips.

FALSE. ASML does not make microchips – we make the machines that other companies use to make microchips. We also don’t make the silicon wafers that form the cradle of the chip. Customers such as Intel, Samsung and TSMC use ASML’s DUV and EUV lithography systems to print tiny patterns on silicon that has been treated with ‘photoresist’ chemicals. They also rely on our metrology and inspection systems, together with our computational lithography and patterning control software solutions, to achieve the highest yield and best performance in mass production.

ASML is the only company that makes EUV (extremeultraviolet)lithographytechnology.

TRUE.UnlikeintheDUV(deepultraviolet)lithographymarket, where ASML competes with other top-notch suppliers, ASML is currently the only lithography equipment supplier capable of producing EUVtechnology. Chipmakers use these EUV systems to manufacture the world’s most advanced microchips. In fact, if you own a relatively new smartphone, gamingconsoleorsmartwatch,chances areyou’vebenefited directly from EUVlithographytechnology.We spent 20years developing EUVwithourpartners and suppliers, resulting in a machine that contains around 100,000 parts. To ship just one of thesehuge machines to customers requires 40 freight containers, three cargo planes and 20trucks.

An ASML machine is all you need to make microchips.

FALSE. Making chips is a complex, long and expensive process.Ourcustomershavespentyearsandinvestedbillions building ‘fabs’ (fabricaion plants), buying equipment and trainingemployeesto become experts inthe complexfieldof semiconductormanufacturing.ASML’slithographymachines form an important part of a chipmaker’s production line, but they are not all that’s required to produce microchips. Lithography – printing patterns on silicon wafers – is certainly a critical step in the chipmaking process, but it’s just one of many!

ASML is building a new kind of EUV lithography machine.

TRUE. In the semiconductor industry, innovation never stops. That’s why we’re already developing a nextgeneration EUV platform that increases the numerical aperture (NA) from 0.33 to 0.55.This means thatthe optics systems in the new machines will allow light with larger angles of incidence to hit the wafer, giving the system a higher resolution. The EUV 0.55 NA platform, called EXE, is well on its way to production – we’re planning the first shipments of these machines to customers for R&D purposes by the end of 2023, and we expect them to be used inhigh-volume manufacturing by2025.

At ASML, we’re changemakers! Our growing team of over 37,000 people and 144 nationalities provides leading chipmakers with the hardware, software and services to mass produce patterns on silicon. We’re probably part of the device you use to communicate, learn or playgames with.

HeadquarteredinEurope’sprolifictechhub,theBrainportEindhoven region in the Netherlands, we have over 60 locations globally and annual net sales of €21.2 billion in 2022.

Curious howyou can be part of progress?

You can contactyour fellow student and Campus Promoter: Cas Dijkstra at cas@workingatasml.com orvisit www.asml.com/students

QUALITY ME

Everyyear students get asked to evaluate their courses.Andwe have made an overviewof the results. The green grades show the overall score for the course and the yellow grade shows the grade for the content of the course itself.

Feedback

• The quality of the lectures is really liked by the students. This makes it easier to stayon track.

4MC10 - Given byprofessors Peerlings andvan Brummelen inyear 3 quartile 1

Feedback

• Therewasalotofpositivityabouttheplanningofthecourse.Thismadeclearwhat to do so itwas easyto stay on track for the course.

4GC00 - Given byprofessor Rokos in year 3 quartile 1

Feedback

• The deliverables took a lot of time for the students and it was di cult to work in agroup. However, they add alot of value for the course and fitwell with the exam.

4DB00 - Given byprofessor Murguia Rendon in year 2 quartile 2

Feedback

• The students really liked the teacher of this course, he was seen as very approachable and always open for questions.

4CC30 - Given by professorVrancken inyear3 quartile 2

Feedback

• The students were very happy with the new progress test system. There was a good explanation towhatthey did wrong.

4RA00 - Given by professors Hulsen andvan Breemen in year 1 quartile 1

Feedback

• The students really like the course, especially the project. Next to this the information is very good structured and updatedverywell.

4TC00 - Given byprofessorvan Beek inyear3 quartile 1

Feedback

• This course is seen as very di cult for most students. Fortunately the quality of thelectures was reallyliked bythe students.

4CB00 - Given byprofessor Chong in year 2 quartile 1

BEST TEACHER SCORE:

Professor Murguia Rendon

WONDERS OF THE ANCIENT WORLD

WRITTENBYMARTIJNZOER

Pharos of Alexandria

The Lighthouse of Alexandria, also known as the Pharos of Alexandria (Pharos roughly translating to lighthouse), was as much a show of wealth and power as it was a beacon directing ships safely to its shores. It was located on what was once the smallislandofPharos,hencethename,whichwaspartofthecity of Alexandria in Egypt. The lighthouse was likely commissioned by Ptolemy I of Soter, a former general under Alexander the Great and bythen ruler of Egypt, around 300 BCE.

The Greek architect Sostratus of Cnidus was responsible for the design according to some sources but he may as well have been the project’s financial backer. Construction would finish somewherearound280BCE.The finishedlighthouseis believed to have been somewhere from 103 to 118 metres high standing on a30 by30 m base andwouldhave been coveredin reliefs and statues.

The lighthouse followed a three-tiered design, with the entire structure sloping slightly inward. The first level had a square base, the second had an octagonal base and the final tier was cylindrical. At the top of the lighthouse a fire burned at night, during daylight mirrors would reflect sunlight. Supposedly the Romans used a rotating mirror system similar to modern lighthouses during theiroccupation of the city.

Likemostbuildingsonthelist,thismarvelofancientengineering would not stand the test of time. It faced gradual decline over the centuries, most catastrophically in the 14th century a series of earthquakes would topple the massive tower. No real trace of the lighthouse remains as most of the ruins were either cleared away or used in the construction of nearby structures such as the Citadel of Qaitbaywhich today sits where the Lighthouse of Alexandria once towered overAlexandria’s skyline.

Citadel of Qaitbay, Alexandria

Colossus of Rhodes

Supposedly being 70 cubits, or 33 metres tall, this bronze statue of the sun god Helios looked over Mandrákion harbour in the ancient Greek city of Rhodes. The Greek king Demetrius Poliorcetes would lay siege to Rhodes in 305 BCE out of fears ofthe mercantile republic supplying Demetrius’enemyPtolemy I, ruler of Egypt, with ships. Partially due to being incredibly unpopular,the siegewould belifted after just ayearin 304 BCE. Demetriuswouldleave behindaheapofsiegeequipment,which the people of Rhodes would sell to the Egyptians. The money earned from this endeavour would be used to erect a massive statue of their patron god, Helios.

The colossus would take roughly 12 years to build, somewhere between 304and280BCE.ThetaskwouldbeassignedtoChares of Lindos, pupil of the famous Lysippos who is considered one of the greatest sculptors of classical Greece and the personal sculptorofAlexandertheGreat.Thestatuewouldbe made upof a white marble base and a frame made up of stone towers and iron beams which would be covered in bronze plates. The exact method of construction is still disputed, the use of an earth ramp to reachtheheights needed is mostlikely.

How the statue would have looked when finished is also uncertain.Foronethepopularideathatitstraddledtheharbour is likely nothing more than a myth. Considering the materials used it would collapse under its own weight in such a pose. It mighthavecovereditseyeswhilelookingatthesunasthisisthe

Mausoleum at Halicarnassus

The Mausoleum at Halicarnassus was constructed to serve as the final restingplace forMausolus,the rulerof Cariain ancient Greece, and his wife Artemisia. Built around 353 BCE in the city of Halicarnassus (present-dayBodrum,Turkey), itwas intended to be a monument that would immortalize their power and wealth.

way Helios was depicted in a nearbytemple. The onlything that can be said with any certainty is the way the head would have lookedlike,with wavyhair and spikes pointing outwards.

The statue would collapse in 226 BCE due to an earthquake and would not be reconstructed as the people of Rhodes believed they angered Helios. The remains would still attract visitors for hundreds of years until theywould be sold for scrap byArabian forces around 654 CE.

The Mausoleum was a blend of various Greek and Eastern influences.ItfollowedaclassicalGreekdesign,characterised by itscolonnadedfaçadeandthesculpturesandreliefscoveringthe structure. Ithoused a central burial chamber, accessed through a grand staircase, which contained the elaborately decorated sarcophagi of Mausolus and Artemisia. The tomb stood roughly 45 metres tall.At the top there stood a statue of a chariot being drawn byfourhorses, ridden by Mausolus andArtemisia.

Greekarchitects Satyros andPythiuswouldbecome responsible for the design. The construction process involved the collaboration of skilled artisans, craftsmen and the famous sculptors Leochares, Bryaxis, Scopas (who supervised the rebuilding of the Temple of Artemis) and Timotheus. Both Mausolus and Artemisia would not see their tomb finished as first Mausolus andlaterArtemisia died before its completion.

Over the centuries earthquakes and invasions took their toll on the structure, reducing it to ruins. Additionally, the remains of the mausoleum were used as a quarry for other building projects, contributing to its further deterioration. Today, only fragmentsofthe originalstructure remain, scatteredamidstthe ruins of Halicarnassus. However, the legacy of the Mausoleum at Halicarnassus lives on, as it served as the inspiration for the term “mausoleum”.

Statue of Zeus at Olympia

The statue of Zeus at Olympia was commissioned by the Olympians for several reasons. First and foremost to celebrate the Olympic Games, the games were held in Zeus’ honor so the statue would act as a connection to the gods. Furthermore, the statuewouldactasabitofatouristtrap,outdoingtheirAthenian rivals and theAthena Parthenos.

The statuewas crafted bythe renowned Greek sculptor Phidias, who was also responsible for the Athena Parthenos. He used a combination of ivory and gold to bring Zeus tolife. The colossal statue stood at a height of approximately 12 metres and sat on a magnificent throne adorned with precious gems and ornate carvings. The process involved intricate sculpting techniques to create the lifelike details of Zeus’ face, hair, and flowing garments.Itwouldtakeroughly8yearstobuildandwasfinished somewhere around 430 BCE.

The Statue of Zeus at Olympia surely was a striking sight. The statue depicted Zeus in a seated position, exuding an air of authority and majesty. Strabo (64 BCE to 24 CE), a geographer, notedthatthe statuegave“theimpressionthatifZeusarose and stood erect he would unroof the temple”. In its right hand the statue held a figure of Nike, the goddess of victory. In the god’s lefthandwas asceptrewith aperched eagle on it.Thethroneon which Zeus satwas covered in intricate reliefs depictingvarious mythological scenes, adding to the grandeur and storytelling aspect of the sculpture.

Temple of Artemis at Ephesus

Between 560 and 550 BCE the Lydian (a kingdom spanning western Anatolia) king Croesus would conquer the city of Ephesus. He would fund multiple construction projects. One of which would be a new temple dedicated to the Greek goddess of the hunt, fertility and childbirth, Artemis. It was believed that a temple in honour of Artemis would bring prosperity and protection to the city.

The statue stood in the Temple of Zeus for over 800 years until it was destroyed in a fire in the 5th century CE. The flames consumed the temple and the statue, reducing them to ruins. Today, only fragments and descriptions from ancient texts remain, providing glimpses into the magnificence of the statue.

TheGreekarchitectChersiphronwasresponsibleforthedesign.

The construction last around 120 years. Pliny the elder praised the engineers for building the temple’s foundation on marshy ground to lessen the e ects of earthquakes. While using layers of sheepskin and charcoal to provide the necessary stability. Evidence of charcoal and soft mortar has been found but no proof of the sheepskins exists.When finished ithad 127 columns measuring around 18 metres in height. The structure would

be around 130 metres long and about 68 metres wide. Reliefs covered the temple depicting among others the Amazons, who supposedlyhid from Hercules in Ephesus.

ThetempleburneddownbyamannamedHerostratus,likelyone of history’s most famous arsonists. According to the biography of Alexander the Great written by Plutarch, the would-be conqueror was born on the same day the temple burned down. It was rebuilt, however, according to excavations this one was slightly smaller at 105 by 55 metres. Alexander the Great even o eredto payfor its reconstruction butthe Ephesians declined, payingforthereconstructionusingacollectionoftheirjewellery.

Over time, the decline of the city of Ephesus and the rise of Christianity contributed to the temple’s further decay and eventual disappearance. Today, only scattered ruins and archaeologicalremnantsstandasatestamenttotheonce-grand Temple of Artemis, serving as a reminder of its remarkable legacy.

Painting by the french artist AntoineChrysostomeQuatremèredeQuincy(1814)

What remains of the temple, near Selçuk

Hanging gardens of Babylon

As of now, there is no archaeological evidence of the hanging gardens noristhere anycertaintyon itslocation.The storygoes that the Babylonian king Nebuchadnezzar II built the gardens for his wife, Queen Amytis, who missed the green hills and valleys of her homeland. Which would have been somewhere between 605 and 562 BCE. This story had been ‘confirmed’ by the Babylonian priest Berossus in 290 BCE. The issue is that no historic Babylonian texts from the time mention the gardens.

Addingtothe uncertaintyisthe factthatnoBabylonianwritings even mention any of Nebuchadnezzar II’s wives let alone Amytis. There are many theories that can account for this lack of evidence. First of all, it is possible that it was nothing more than legend. The Greek and Roman writings we have could have been nothing more than romanticized ideals of eastern gardens. Another possibility is that it did exist in Babylon but was destroyed somewhere around the first century CE. Or the writings could be referring to a di erent garden built by the AssyriankingSennacherib(whoruledfrom705to681BCE),built in Nineveh on the riverTigris.

TheideathatthefamousgardenswereinfactlocatedinNineveh was put forward by Oxford scholar Stephanie Dalley. She listed ways in which over the centuries the location of the gardens could have been confused. For example, Babylon means ‘gate of the gods’, not only did multiple Mesopotamian cities have this name, but Sennacherib named Nineveh’s gates after gods. This suggests that he might have wanted Nineveh to be considered

Great pyramids of Giza

The only of the 7 wonders that is still standing, as well as by far the oldest and probably the most famous is the Great Pyramid. The Great Pyramid of Giza, the oldest and largest of the three pyramidsinGiza,wasconstructedasamonumentaltombforthe pharaoh Khufu (also known as Cheops) during the Old Kingdom period of ancient Egypt. Built around 2560 BCE, the pyramid servedasafinalrestingplaceforthepharaoh,aswellasasymbol ofhis powerand eternal presence in the afterlife.

a ‘Babylon’. Sennacherib’s garden was definitely a great feat of engineering. A massive irrigation network featuring water screws provided water to his year-long oasis. To supply the city with this increased need for water over 50 km of canals reached the mountains. Part of this network was a massive aqueduct spanning the Jerwan valley, containing an inscription attributing itto Sennacherib. He claimedhe had built a ‘wonder for all people’.

Construction of the Great Pyramid of Giza was a massive undertaking that required the coordination of thousands of workers, architects, and engineers. It is estimated that it took around 20 years to complete. The pyramid was built using limestone blocks, which were quarried and transported from nearby sites. These enormous stones were carefully cut and precisely placed to create the pyramid’s iconic triangular shape. The construction process involved complex engineering techniques, including the use of ramps,levers, and pulleys tolift and position theheavystones

The Great Pyramid of Giza shows the exceptional craftsmanship and precision of ancient Egyptian builders. It has a square base where each side stretches roughly 109 metres and the pyramid rises to a height of about 147 metres. It consists of a series of carefully layered stone blocks, with the outer layer originally covered in smooth, polished limestone casing stones. The interior of the pyramid contains a network of chambers and passages, including the burial chamber where the pharaoh’s sarcophaguswas placed.

Despite being thousands of years old, the Great Pyramid of Giza hasremarkablywithstoodthetestoftime.Whiletheoutercasing stones have largely been stripped away over the centuries, the core structure of the pyramid remains intact. It continues to be a prominent and awe-inspiring landmark, attracting millions of visitors each year. The Great Pyramid stands as a testament to the ancient Egyptians’achievements andhumanity’s ingenuity.

Relief of the gardens at Nineveh

LANDYACHTING TRAILER

A story of heartbreakand heroic building

As most of you are aware, the studyAssociation WSV Simon Stevin used to own a glorious space in Gemini called “De Werf.” This space was known to most members as a place to work on projects either for oneself or related to a course. However, to the members of the Land Yachting committee, “De Werf” meant much more. It was the place where most of the iconic land yachts owned by the Association were created and stored. With the move to Traverse and the remodeling of Gemini, it soon became clear that a space of this kind would not be available anymore. While finding storage for most of the equipment and some materials was possible, storing the land yachts within the alloted space was impossible. Thus, another solution had to be found. This led the committee to propose converting the land yachting trailer from open to closed to allow it to hold theland yachts on a more permanent basis.

WRITTENBYGLENNLANGERMANS

Adesignwas drawn up,andapresentationwasheld.Aftersome deliberation, the GMM (General Members Meeting) decided to investtherequestedfundstobuildthetrailer.Withtheirmandate secured,three members ofthe LandYachting committee setout to build it during the summer holiday, using the workshop at “Van Adrichem Kwekerijen.” The first order of business was acquiring the required amount of steel, fasteners, aluminum, and paint to build according to the design’s calculations. The steel was then cut to the right sizes and angles to form a square box, which was welded to the floor of the trailer. Small diagonal pieces were added to increase the frame’s sti ness.

Once the basic boxwas finished, the frames thatwouldhold the land yachts were added on the inside. Also, on the front of the trailer,anosewasinstalled,whichhangsabovethejockeywheel. This process involved a significant amount of welding and drilling. The drilling was done with the purpose of creating an adjustable rack on which the smallerlandyachts could behung, and support arms would be addedlater. A special compartment was created to hold the masts of the land yachts, as some of them were too long to fit nicely in the trailer. Paint rollers were added to this compartment to allow for smoother insertion and removal of the masts.

Next, the floor, consisting of aluminum diamond plate, was cut tosizeandshape.Itwastheninstalledusingself-drillingscrews. Unfortunately, the screws purchased for this purpose were a bit too weak to punch through the steel carriage of the trailer. As a result, they had to be pre-drilled, which took a significant amountoftime. Moreover,carehadtobetakenwhentightening thescrews,astheywerepronetobreakingiftightenedtoomuch. So, here’s a pro tip: do not buy very small selfdrilling screws, as theyare prone to breakage and do notworkwell.

After installing the floor, the entire frame was given two layers of primer and two coats of color. The painting process, carried out with brushes or rollers, took more time than expected and required an additional Saturday outside of the holiday to complete. (Quick note: painting when it is dark outside can result in aless even paint job.) Once the sides of the trailerwere added, itwas taken to the sailmaker to receive its sail. The sail’s color was chosen as a nice shade of blue, and the concept of encapsulatingtheendsofthemaststhatstickout(oftenreferred to as the mast condom) was decided upon.

With the realization of the vision presented at the GMM, a few more things had to be done. Guters were added inside the trailer to facilitate the rolling of the larger land yachts in and out with relative ease. The originally chosen guters proved to be not strong enough, so they were replaced with PVC guters, which were further supported using wooden batens. The final step was adding supportlegs to the trailer to prevent its wheels from becoming flat due to thelong periods of standing stillwith a now increasedload.

The finished trailer nowhas a current capacity of 7 land yachts, which can easily be increased to 8 as long as the additional land yacht is of the same type as Bobbie (ed. The name of one of the smaller land yachts). This results in an increase of weight (without anylandyachts) of 200kilograms.

TRAILER BUILDING RECIPE

THE WANKEL ENGINE

There are many types of internal combustion engines, the most common ones use reciprocating pistons, such as the one you might see in cars today. Or another common form is continuous combustion which is used in gas turbines or turbojet engines. However, another not-so-common variant of the internal combustion engine is the pistonless rotary engine.

The pistonless rotary engine replaces the linear reciprocating motion of a piston with a more complex compression & expansion motion caused by the geometry of the rotating axis in the case. Not to be confused with the rotary engine, which has a stationary crankshaft and a rotating crankcase. One of the fundamental advantages is that it is possible to have a more compact and materiale cient design.

Removing the reciprocated pistons decreases the mass and rotational inertia of the engine. As there is less mass moving far out from the center of rotation and less counterweight to counteract the vibrations of the piston. On top of that, the amount of vibrations is also decreased. Thisresultsinfewerforcesonthecrankshaftoftheengine, making it possible to use less material and run the engine at a higher RPM. Because of this, the specific power of a pistonless rotary engine is usually higher. I.e., it produces more power forthe givenweight of the engine.

However,creatingapistonlessrotaryengineusuallycomes with two big problems: large sealing paths and a large surfaced-to-volume ratio in the combustion chamber. But there is one engine design that overcame these design challenges and has found commercial viability: the Wankel engine.

Wankelenginedesign

The basis of the Wankel engine design is the triangularshaped rotor within an oval/eight-shaped housing. The rotor has three convex faces that act similarly to the faces of a conventional piston. The rotor moves in its rotating motion guided by gears and the eccentric output shaft, not being guided by the external chamber. Importantly, the apexes are sealed so gasses do not escape from one chamberto another.The geometrycan be seen in Figure 1. During the rotation, each face of the triangular rotor is in one part of the four-stage Otto cycle: intake, compression, ignition and exhaust as can be seen in Figure 2. Because there are three faces of the rotor itgets three powerpulses perrotationoftherotor.Nexttothat,thereisathree-to-one reduction between the crown gear and pinion resulting in one powerpulse perrotation ofthe shaft.Comparatively,a four-stroke engine has a power pulse every other rotation of the shaft.

Because of its more consistent power delivery and lower moment of inertia, it can run at a higher RPM of up to 7,000 or 8,000. Being onlylimited bythe tooth load on the synchronizing gears.

WRITTENBYBENGORTEMAKER

Figure1:SchematicoftheWankel:

1. Intake

2. Exhaust

3. Statorhousing

4. Chambers

5. Pinion

6. Rotor

7. Crowngear

8. Eccentricshaft

9. Sparkplug.

Figure2:TheRotaryCycle:

1. Intake(blue)

2. Compression(green)

3. Ignition(red)

4. exhaust(yellow)

to release its first car in 1967 the Mazda Cosmo. And unlike NSU, Mazda claimed to have solved the large problems with the apex seals and lubrication.

Mazda tried to use rotary engines in other types of vehicles but decided to stick to using the rotary engine only in sports cars only. However, they stopped production ofrotaryenginesas thesecouldnotcomply with the Euro 5 emissions standards anymore, leaving nomoreautomotivecompaniessellingrotary-powered engines.

OriginoftheWankelengine

The origin of the Wankel engine does not start with making an engine, but a compressor. As Felix Wankel starteddesigningrotarycompressorsinthe1920s.And only in 1934 got his first patent for the rotary engine. In 1951 he started NSU Motorwerke, to design a rotary compressor as a supercharger for NSU’s motorcycle engines. And finally, in 1954 NSU agreed to start developing a rotary engine, based on the compressor design. This resulted in a working prototype on the first of February 1957. ¬¬The prototype could produce 21 horsepower, after which four other prototypes were builtwhichcouldmake29horsepower.Thisresultedin the first commercial car in 1964 called the NSU Wankel Spyder.

ProblemswiththeWankelengine

One inherent design flaw of the Wankel engine is the fact that there are sealing paths. All sides of the combustion chamber must have tight high tolerance seals so that little gases escape during combustion. Or the seals need to be spring load to remain a tight seal, however, this creates more friction inside the engine and makes it work less e ectively at low engine speed. It also creates a part that needs regular maintenance. On top of that it is also more di cult to lubricate these seals and or prevent the lubrication from burning in the engine.

Next to that due tothe long and flat chamber shape the combustion occurs less evenly and progressively. The flame front itself is smaller and the mixing of the fuel happens less evenly. Due tothis unevenburning not all the fuel gets used during the combustion, decreasing the fuel e ciency of the engine itself. On top of that, this uneven combustion also creates high emissions of part-burnt hydrocarbons.

Commercial use of the Wankel engine

NSU had a study partnership with Mazda for the Wankel engine, and they competed in making the first rotary-engine car. As said before NSU was the first to do so,however,thiscarhadalotofreliabilityproblems causing frequent engine failures. Which ruined the reputation of NSU. However, Mazda waited longer

FutureoftheWankelengine

ThefutureoftheWankelengineasitwas,isnotlooking very bright. However, recently it seems to be getting a kind comeback. Finding new and unique uses of the engine. One of these is by using the Wankel engine as a range extender in a car. This way it does not drive the engine directly, but drives a generator instead. This was chosen due to the light design of the Wankel engine. This can be seen in the newest Mazda MX-30 R-EV.

Another potentially useful case for rotary engines is with hydrogen-fueled engines. Because hydrogen has better mixing and ignition properties it solves the problemoftheunevencombustion.Ontopofitdoesnot have rubber seals, which may be negatively a ected by hydrogen.However,itdoeshavebadexhaustbehaviour as it still produces more NOx.

Lastly, there are also companies such as LiquidPiston that are still innovating the engine and taking advantage of the high power-to-weight ratio.

Figure 5: Mazda MX-30-R-EV

Figure 3: NSU-spider

Figure 4: Mazda Cosmo

CAMPUS ART

The university does a lot to make you feel welcome on campus. There are many places to eat food, study and just generally hang out. An often overlooked aspect of the decorations on campus is all the artworks that can be found here. In this series of articles, I want to find outwhat people think of the abstract art that the campus provides, but in a mechanical engineeringway. Ihave asked mechanical engineersto gradethese artworks based on some core DBL values to evaluate every piece of art. These values are e ciency (how clear is the interpretation of the artwork), craftmanship (how nice does it look), and creativity (how original is the artwork).

Van bar tot Bank (K.O.E.)

“Van bar tot Bank (K.O.E.)” (From bar to couch) is a large concrete constructionlocatedonthefieldnexttotheauditorium.Theacronym in the name means “Kunstobject Ontmoetingsplaats Eindhoven” (Artwork Meetingpoint Eindhoven). It was placed on campus in 2013 and has since been a part of many events that were organised there. Sincethen, manyhavetried to climb itbutonlya fewhave succeeded due to its large size without many places to hang on to. Very little information could be found on this artwork online, some sources even claiming that it isn’t part of the art collection. Its creator is also unknown.

E ciency:

Craftmanship:

Creativity:

Objet Mathématique

“Objet Mathématique” (Mathematical Artwork) is a large metal construction with LED lights that can be found at the end of the “Limbopad”. It was part of a large exhibition created by Philips for the World’s Fair in Brussels (1958) called Poème électronique (Electronic poem), which can be read on the front of the artwork. It was made by the artist Le Corbusier and the poem itself was an 8-minute composition played bymore than 400 speakers. In 1998 the artwork at the entrance of the exhibition, Objet Mathématique,was given to the TU/e.

E ciency:

Craftmanship:

Creativity:

WRITTENBYJASPERBEKKERS

Vliegende amazone

“Vliegende Amazone” (Flying Amazone) is a small bronze statue that can be found between Atlas and Auditorium. It was made by Arthur Spronken and placed on the TU/ e campus in 1965. Spronken was known for creating statues of bodies, dancers and torsos of horses. These are always presented in a dynamic way: floating, dancing or running. This particular artwork mentions anAmazone.This could mean multiplethings, butknowingthe artist’slove for horsesitprobablyreferencestheDutchword“Amazonezit”(ridingsidesaddle). This is a way of riding a horse with both of yourlegs on the same side. To this day, no one has been able to find the angle where the statue could actually resemble the torso of ahorse.

E ciency:

Craftmanship:

Creativity:

Wording

“Wording” is a large statue placed at “De groene loper” in front of Atlas. It wasmadebyPietKillaarsin1968.Thenamemightbeconfusingasyoumight first think it’s in English, but it used the Dutch word which translated to “Starting to exist”. It’s placed in the water and combined with the name one could interpret it as if the statue grew/evolved out of it, just like the first land animals did when theywalked onto land. But the statue was not always in the water. During the renovation of Atlas, the pond was filled and turned intoafield.Duringthisrenovationthe statuewas unbothered.Andwhenthe pond came back, so did the statue return to its setting where it still rests to this day. Maybe the statue does not stand for growth by itself but acts as an anchor forthe ever-changing campus around it.

E ciency:

Craftmanship:

Creativity:

THE INTERNET CAN SHOW US CRAZY THINGS: DEEPFAKES

WRITTENBYVEERLEBUS

The internet can show us crazy things. The most random and funny things can be reposted and go viral. Videos are sometimes edited in a specific way, which is can be misleading from reality.The samewayfilters are applied to a selfie to make everythinglook abit better. Something that goes even one step further, is a deep fake video or image. As the name itself explains, it is fake to a deeperlevel ofwhereyou do notknowanymorewhat is true andwhat is not. It is a new artificial intelligence technology which can generate a video or image where people do things they never did. While initially used for entertainment purposes, such as swapping faces of celebrities or adding someone’s face to a movie clip, it has the potential to be used for more sinister purposes.

Whatisadeepfake?

Deepfakes are created by using deep learning algorithms to analyze and mimic patterns in large datasets of photos and videos of a person’s face and voice. These algorithms can learn to generate realistic-looking videos or images of that person, even when they are saying or doing things that they never did in reallife.

The technology behind deepfakes is known as generative adversarial networks (GANs), which involves two neural networks; ageneratorandadiscriminator.Thoseworktogether tocreatetherealisticimagesorvideos.Thegeneratorpartcreates the media content, while the discriminator determines whether it is real or fake. As the generator improves, the discriminator becomes better at detecting fake media, resulting in a feedback loop that produces increasingly realistic deepfakes. A di erent example of this technology is the website ‘This-person-doesnot-exist.com’, which will generate a random person that looks like a person,who does not actually exist.

Whycandeepfakescauseconcerns?

It is not that hard to manipulate a video and put it online on the internet. Some people mightassume itto be true and others will have a more critical look towards it. The dangerous part of deepfakes is that it makes the separation between real and ‘maybenotreal’alotharderandthegroupwhowillhaveacritical lookwillbecomesmallerandsmaller.Therefore,deepfakesarea significantthreattoprivacy,securityanddemocracy.Theycanbe

usedtodefameorblackmailpeoplebycreatingvideosorimages that damage their reputation or credibility. A victim of this was Emma Watson, whose face was put on porn advertisements. A di erent purpose of using deepfakes is creating fake news or propaganda, which can influence the public opinion or create violence. A deepfake video of old president Obama was made to warn people about the possibilities of deepfakes, where he quoted ‘President Trump is a total and complete dipshit’. The last concern that deepfakes cause, is that it can be used for identitytheft. It can impersonate someone else and access their sensitive information.

Howtodetectadeepfake?

Currently, companies exist that try to validate whether a video or image on the internet is real. For example, ayearago, avideo where a rat was in the soup of a big Chinese food chain was posted. This damages the company’s reputation a lot, that is where the companies come in to checkwhetherthe perspective of the video is the actual real life truth that happened. This example does not showcase a deepfake video, however, those companies can also encounter deepfake videos.

There is also technology which is being developed to detect deepfakes online. Researchers are developing algorithms that can analyze the inconsistencies and artifacts in the images or videos that are not present in real media. They detect patterns and anomalies inthe data,which indicateswhetherthe mediais authentic or fake.

Funapplicationsofdeepfakes

Deepfakes can cause a concern as the technology develops further and further, however, there are also a lot of fun applications of deepfakes. One application that most people know, is face swap. This was introduced a few years ago and it swaps faces of people, as the name itself explains. To take this evenastep further,theappWombowas created.The ideaisthat you can upload an image and select one of the many sounds on the app and that the app will generate a singing video for you. Yourcreativitycanrunwildbecauseyoucanmakeyournewborn nephewsingafull rapsongoryourdadanoperaballed.ADutch online platform called ‘Diepnep’ (which is the literal translation of ‘Deepfake’) creates videos to show the dangerous sides of deepfakes in a funny manner. For example, there is a video of our king Willem-Alexander singing a song about the corona virus on his guitar or a video of Kim Jonghyn dancing as if he is making a Tiktok. Most of their videos are a joke, so it is clearly visible that is not realistic, however, they also have one video of where they impersonate Morgan Freeman.As second post, they have a video of a white man speaking the text and making the movements Morgan Freeman makes. This ishighly realistic and shows the potential of deepfakes verywell.

Deepfakes have the potential to create significant harm and damage to individuals, organizations and society as a whole. On the other side, it also has a lot of fun applications and cool things can come from it. While detecting deepfakes can be a challenging task, research and development of tools to search harmful deepfakes is ongoing.

St: the student life of San Diego

The stigma of a lifeless university

Haveyou everplannedto enjoyapleasant beerforthe price of asausage rollto celebrate the end of a tough study week? Then you are not the only student in Eindhoven, let alone the Netherlands, who likes to raise a glass and enjoylife. Our small country is bursting with the most pleasant student cities, but in Eindhoven, the warmth of Brabant flows through the veins of the university campus. This is, of course, no accident since the university is within walking distance of the train station and is centrally located in the city. All associationa and social spaces are easily accessible, open to every socializer, and student life has strong support from the department.

WRITTENBYBASBURKSEN

However, not every student is lucky enough to be part of a vibrant campus. After all, a university is intended for serious, civil matters such as research, lectures, and obtaining degrees. The developmentof astudentas aperson can easilybelost sight of in this goal. The American education system is notorious for itshighpressuretoperformfromayoungage.Actuallyobtaining a place at a top university is statistically rarer than graduating with a degree in mechanical engineering.

Is there still room for conviviality, camaraderie and the muchneeded social life that every student needs to grow as a person? Not everywhere. In the southwesternmost point of the United States, at the border with Mexico, lies the city of San Diego. This city, where the sun always shines and rain is a mysterious phenomenon, is home to two major universities: San Diego State University (SDSU) and the University of California San Diego (UCSD). They could not be further apart when it comes to student culture and liveliness on campus. Where one student cheers deafeningly for sports teams every week and attends unforgettable parties,UCSDisknown asthe mostboring,lifeless

place in Southern California. How can a university where more than fifteen thousand students live on campus have such a bad reputation for atmosphere andliveliness?

In1960,anewcampusoftheUniversityofCaliforniainSanDiego was founded, abbreviated as UCSD. The campus was quickly filled with impressive, modern buildings. Taking a walk, one is quickly overwhelmed by the concrete force that these buildings exhibit. These buildings are textbook examples of the so-called Brutalism movement, intended to highlight the simplicity and roughness of building materials. This description may sound very familiar to the local mechanical engineering student. The Auditorium, Gemini, and, for the true connoisseur, the Bunker, are also classic examples of Brutalism. The original home of the mechanical engineer, Gemini, is even the first winner of the illustrious “Betonprijs”.

About fifteen thousand students live on the UCSD campus. However, the campus cannot be called lively. Where we in Eindhoven are used to unforgettable introduction parties and infamous carnival drinks, students in San Diego mainly complain about the lack of conviviality and events. Moreover, UCSD is primarily named in the list of the most boring, lifeless universities. Of course, the concrete buildings do not radiate much conviviality, but if it could be pleasant in the dark, sweaty basement of Gemini every Thursday afternoon, there must be more behind thelackof atmosphere on the Californian campus. The location of a campus has a significant impact on the atmosphere and mood among students. This university is not located in the center of a bustling city, but in a calm, a uent suburb on the coast. It is also only accessible by car; Cycling or public transportation is not a practical option, especially for parties that go late into the night. Additionally, many American students have a di erent mindset than what is familiar to the Dutch. While in the Netherlands, with a VWO diploma, one can always get into a highly regarded university; American

The Giesel Library

universities like UCSD accept only a fraction of the applications. To live on a prestigious campus, a teenager must stand outhead andshouldersabovetherest.Thisperformance-drivenmentality resultsinthedistortedideathatstudyingismoreimportantthan the social studentlife.

The students themselves, but especially the university, have the responsibilityto bring atmosphere and convivialityto a campus. Looking at the UCSD campus, they have missed the mark here. There are even theories that claim that the lifeless and grayness ofthecampuswasadeliberatechoice.Atthetimeofthefounding of the university, it was a tumultuous time in the United States, especially California. In the 1960s, the University of California Berkeleywasplaguedbyheavyprotests,whichultimatelyresulted in a politically charged struggle between students and the government. After much violence and intervention by political leaders, the protests came to a standstill, but the reputation of the universityin Berkeleywould never be the same.

At this time, a new campus of the University of California in San Diego was also being built. There are many indications thatlead to the theory that this campus was deliberately built to limit the gathering of students. For example, the student residences are far apart, and the footpaths seem designed to hinder the flow of protesting students. Even the central main building is designed in such a way that it is practically impossible to carry out an occupationlike the Maagdenhuis in 2015.This goeshand inhand with the fact that the brutalist architecture gives the campus buildings the appearance of a bunker. The university will never admit it, but the student protests of the 1960s in Berkeley seem to have had a significant influence on the deliberate choice to designthe campus so devoid of atmosphere.

Allinall,thereareseveralsidestothestorybehindthelifelessness that the University of California San Diego is struggling with. The buildings are spectacular but quickly remind students of the well-known concrete structures like the Auditorium and the concrete award-winning Gemini. The campus itself is located in a boring, expensive suburb, rather than in the middle of a bustling citycenter,like manypopularuniversities.Additionally,

the campus is only accessible by car, and you better leave your bike at home. There seem to have been deliberate choices made during the founding of the university in designing the campus after the out-of-control student protests in Berkeley, making it di cult for large groups of students to come together, let alone organize an unforgettable party.

However,the atmosphere and convivialityof auniversityare not only determined by designs, accessibility or history. The UCSD campus is full of hardworking students who value high grades morethanasociallife.Ontheotherhand,themostunforgettable activities on the Eindhoven campus are organized by none other than its very own students. We should be proud that “our” university has a culture full of conviviality and is bursting with sociallife,nomatterwhatstudyyouarein.Ifyoueverspendtime at a foreign university, as I recently did, take this “Eindhovense gezelligheid” with you. Take the initiative to expand your social life, meet new people, and if necessary, bring some atmosphere tothecampusyourself.Whoknows,itmightleadtounforgettable memories.

Occupation of the Maagdenhuis of the University of Amsterdam in 2015

CROSSWORD

Do you know all of the things that are in De Weeghconst well? Then this puzzle should be a breeze. If you don’t it might be time that you come by for a visit and ask around what all the things that are around you are!

PUZZLESMADEBYRIKTIEBEN

SLITHERLINK

This puzzle consists of a grid of points where each space between four points forms a cell. The number in the cell indicates how many sides of the cell is hit by the line. The object is to create a single room of this one connected line. In addition, it is not allowed to have the line cross itself

SAMURAI SUDOKU

A Samurai Sudoku puzzle consists of five interwoven Sudoku grids. The standard Sudoku rules apply to each 9x9 grid. Place the numbers from 1 to 9 in each empty cell. Each row, each column and each box of 3x3 must contain each digit.

STERRENHOEKJES

• Koen: “de ouderejaars zijn tegenwoordig niet oud meer”

• Bas tegen Ferenc: “Soms denk ik: Je werkt goed, je kan echtheel veel. Maarheb ikwel wat aan jou?”

• Elle: “Ik ben standaard overprikkeld na BACoverleg.”

• Niels tegen Noor: ‘Ik ken niemand die zo slecht kan luisteren als jij, en de moeder van een maat van mij is doof’

• Sandor: “Bregje, je doet me nu echt denken aan Stephen Hawking hoe je nu zit”

• Ben, Stijn, Pieter, Jankatiri, Tom en Ferenc: “HOEBA HOEBA HOEBA HOP HOP HOP”

• Jens:”Ja, de WoF is bijna vol” 18de Bestuurslid: “Mooi tijd om m weg te gooien dus”

• Kevin over de kritiek dat onze vereniging niet woke genoeg is: “Wij zien geen verschil tussen mannen en vrouwen, wij zien alleen leden.”

• Pieter: “Eigenlijk is een Beef Wellington gewoon een duurworstenbroodje”

• Jelle die een foto maakt: ‘volgens mij staat er een filter aan want Sandor ziet er nu knap uit’

• Bas: “Ik ben nietvan de straat, ik ben van de laan”

• Kim: Wat is experimental design? Jack: Klinkt als beunen.

• Imand over de hond van haar nicht:”Ja die heet dus Tiara” Mathijs: “Jezus ik zou een stripper nog niet eens zo noemen””

• Lichten in de collegezaal gaan uit. Hans Kuerten: “ooh fire alarm, I thought that only happens during exams.”

• MevrouwdeSecretaris:“Erisbeslotendaterniemand in zowel de RvA als OFAC mag zitten omdat je dan lastkrijgtvan je ruggegraat........ Uh ruggespraak”

CONTEST TIME

Submit

Contest54.2

The CoBA, Pieter, has ten indistinguishable sealed kegs in his storage room. Pieter knows that someeven numbern ≥ 2 ofthesekegs contain beer,whereasthe other10 − nkegs containhighly toxic acid, alsoknown as Heineken. Unfortunately, he has forgotten the exactvalue of n.

Pieter’s Beer Testing Machine (BTMTM) has two compartments, a huge red button and a light bulb. If he puts one keg into each of the compartments and then presses the red button, the BTMTM wakes up and starts to work. After one hour, the bulb lights up in green or red. If the bulb lights up in green, then at least one of the two bottles contains the delicious golden liquid. If the bulblights up in red, then neither of the two kegs contain beer.

Pieter needs two kegs for the borrel. How often does he have to use the BTMTM (in the worst case) in order to identify two kegs containing beer?

SubmityouranswerinDeWeeghconst(Traverse0.34)orviaane-mailto redactie@simonstevin. tue.nl with your name and the solution. The prize will be ra ed from the correct submissions and the correct answerwill be published in the nextwinning contest.

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