Simon Ster 49.3

Simon

Volume 49 | Issue 3 | March 2018

A 3D printing contest The technical aspects of sports Course evaluations Student teams

36

6 In this edition we have a lot of studentteams and associations, who talk about what they do. Blue Jay is one of them and on page 6 you can read about the unique robot they are developing.

Eindhoven is located in one of the most high-tech regions in the world.

One company who also contributes to this is Sioux and in their article they tell you about their new wafer, which is being developed right now.

40

18 Another quartile, another evaluation. See what students have to say about current courses and how teachers react to it. Reading it may give you an explanation for the same problems you have observed.

Colophon March 2018, volume 49, issue 3 The ‘Simon Ster’ is a publication by the study association of Mechanical Engineering Simon Stevin of Eindhoven University of Technology . The ‘Simon Ster’ will be published five times this year.

Editor in Chief Lex Verberne

Editorial Committee Daan van Boekel, Loes van den Beuken, Sebastiaan van Kemenade, Ruben de Klerk, Robbert Louwers, Stijn Middelhuis, Fercan Molenaar, Lex Verberne, Kelsey Viehmann

Design vM-design

Layout

Contact Eindhoven University of Technology Gemini-Noord 1.61 Den Dolech 2 5612 AZ Eindhoven Postbus 513 5600 MB Eindhoven Phone: (040) 247 33 13 E-mail: redactie@simonstevin.tue.nl Homepage: wsv.simonstevin.tue.nl

Financial ABN-AMRO: NL87ABNA0529096358

Subscriptions It is possible to receive the Simon Ster at home.

Subscriptions for the Simon Ster are available for an annual fee of €15,- , including shipping. In case you are interested or want more information, it is possible to contact the editor at aforementioned adress.

Fercan Molenaar Ruben de Klerk Lex Verberne

Printing Office Illustrations and Pictures Editorial Committee, PaparaCie and members of W.S.V. Simon Stevin

With everyone still recovering from the Winter Olympics, you can discover on page 40 that ice skating is probably older than you think . So make sure you know all the history it comes with when you put on your ice skates next time.

Drukkerij Snep BV

Circulation 900 pieces

© Simon Stevin MMXVII Nothing from this edition may be duplicated and/or made public by means of press, photocopy, microfilm or any other possible manner without prior written consent from the board of W.S.V. Simon Stevin.

The editors at all time reserve the right to shorten and/or edit articles. The placement of an article does not mean that this in any way reflects the opinion or point of view of W.S.V. Simon Stevin.

Everyone can deliver articles to the Editorial Comittee in the Simonkamer: Gemini-Noord 1.61 or by means of e-mail: redactie@simonstevin.tue.nl

Table of Contents Smile of Science

4

Blue Jay

6

Hockey and science

8

Zweefvliegen met de ZES

10

URE 12 Hephtig: Referendum

14

Company Visit: NTS-Group

16

Course Evaluations

18

Moving Bridges

19

Uit den oude doos: Sport en Techniek Team FAST staut: Cornelis Lely

20 22 24

Climbing 26 AME 3D-Printing contest

29

Bachelor Final Project

30

Land Yachting in the desert

32

Taekwondo 35 A new Wafer Feeder

36

Windsurfing 38 Ice skating

40

Contest 42 Sterrenhoek 42 Planning 44

Dear reader, It hasn’t been long ago since the last edition of the Simon Ster was released, but fortunately for you, you already have the new one in your hands! As you may have guessed from the cover, this edition is all about sports. We talk about people who have done land yachting in the desert, how taekwondo was invented, why ice-skating is such an ancient sport and much more. In our association we have a lot of dedicated athletes who love the sport they do and some who even excel doing it.

At the moment we live in a high-tech world and this is reflected on sports as well. It is interesting to see how every day, engineers work on developing better shoes for basketballers or make suits for ice-skaters more aerodynamic, all to shatter earlier world records or just make sporting easier for amateurs. But we also learn more and more about the human body and how we can optimize training schedules and diets for every athlete.

This combination makes sports an interesting field for engineers and other researchers, who can still optimize techniques we have always seen as normal.

So as always, you are needed as a mechanical engineer to invent products, also in fields you might not expect in the first place. Make sure to use your knowledge and maybe one day you can add something to the process of optimizing sports as well.

Advertisers DAMEN 11 Wervingsdagen 17 AME

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Sioux CCM

36

VDL 43

Lex Verberne Editor-in-Chief

4

Smile of Science

Stijn Middelhuis

Sense and Nonsense in sports technology

Tech

Inspired by insects Scientists are not only developing new materials but also helping sportsmen and women improving their techniques. Josje van Houwelingen, a physicist at the Eindhoven University of Technology in the Netherlands, has developed a new system to improve the strokes of elite swimmers. The system involves creating small bubbles at the bottom of a swimming pool and using an array of six cameras together with a fluid-dynamics algorithm to study how a passing swimmer affects the motion of those bubbles.

Van Houwelingen is particularly interested to find out whether swimmers could boost their propulsion by creating certain kinds of vortices, just as insects take advantage of vortices they create in the air as they flap their wings. “Insects have been observed to get extra propulsive force by pushing against those vortices,” she says.

“Maybe swimmers could get a similar benefit.”

This is just the beginning. Cycling may see the advent of sprayon clothing that keeps riders dry and safe but also light, as well as sensors to monitor a rider’s physiological changes and “phase-change” tyres that vary their tread, depending on terrain.

“Human Enhancement Technologies” could also become far more widespread. South African amputee runner Oscar Pistorius caused controversy when he competed in able-bodied competitions using artificial limbs, but in the future biomedical devices and prosthetics may be used by athletes to enhance their capabilities rather than simply restoring them.

training

Health

Smart Soccer Ball

Keep track of what you drink!

Adidas’ miCoach allows soccer players to track their skills digitally. The ball measures speed, spin, trajectory and strike point through a sensor located in the center, and sends the data to a paired wireless device. It also lets you know the flight path of a ball, so if you want to learn how to bend it like Beckham, you can know exactly how much force you have to exert and where you should place your kick.

To help sportsmen with rehydrating, Smart Caps are developed. Smart Caps work with a chip-enabled skin patch to determine when athletes are dehydrated and how to optimally rehydrate.

Gatorade, in collaboration with Smart Design, is developing a “first-ofits-kind hydration tracking and personalized sports fuel delivery system.”

On the outside, miCoach looks like a regular soccer ball and is the maximum FIFA-approved weight, so it’s no different than playing with the real thing!

The technology gathers information using a bottle smart cap and chipenabled skin patch, according to Mashable. The smart cap’s microchip will share real-time hydration data and the skin patch works with an app to determine sweat level, electrolyte needs, and fluid intake requirements.

From these readings, an algorithm gives hydration suggestions, which corresponds to different Gatorade formulas. The brand is creating 12 different egg-shaped pods which snap onto the bottle and deliver different combinations of electrolytes, carbohydrates, and calories.

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Simon Ster 49.3 | March 2018

Tech

Predictive tennisplayers Not only football has innovations for the players. SAP Software & Solutions believes it can use data-crunching techniques to break down not only a tennis player’s stats, but predict their moves in advance.

High-Tech

Smart basketball court Sometimes the best way to learn something is by combining your own experiences with the experiences of others. A basketball court in Shanghai called The House of Mamba, named after Kobe “Black Mamba” Bryant, applies that principle to the sport with the help of cutting-edge technology.

The House of Mamba is a smart basketball court developed by tech company AKQA and Nike. It has a floor that lights up to guide players through expertly designed training programs. The court is comprised of LED screens, sensors, and motion-tracking devices, so coaches can upload programmed footwork routines for their teams to follow. Then, players look at the brightly lit floor display and make sure that their real steps line up with the ideal form for several basketball drills, including dribbling a basketball or playing defence against a hypothetical opponent. Artificial intelligence tweaks the program to help players practice the skills they need to work on, and muscle memory theoretically kicks in so that athletes will know what to do when they’re playing for real.

The court was created for a Chinese reality TV show called Nike Rise, which was a competition where participants were mentored by LeBron James and Bryant for the chance to compete in the Nike World Basketball Festival. Lest you think this is a gimmick cooked up by a marketing department, the digital court was created with Bryant’s input, and debuted with five custom practice programs based on the Lakers shooting guard’s prowess.

The German software company claims its HANA platform can break down a player’s style and choices into probable likelihoods. The algorithms do this by “watching” serve direction, return contact point (where a player is when he returns the serve), shot placement (which includes everything from where the ball lands to slice, topspin, and speed) and player movement (imagine a heatmap of a court showing where a player was and how often).

Once that data is compiled, HANA calculates the probability of what a player is likely to do at any given point of the match. So imagine your opponent’s serve bounces just in front of the service line on the right-hand side of the court. HANA can calculate where you’re likely to be when you return it, and the speed and spin of the return shot you hit.

Not only can that sort of knowledge help players understand what their opponent is going to serve up and when they are at their strongest themselves, but commentators could use the predictive models to prepare for what’s coming next.

SAP partnered with the Women’s Tennis Association to show off the technology in August, allowing coaches to see how their players performed after a match. The Wall Street Journal reports the WTA may allow coaches to tap into that information in real time, which could change the sport at a blistering speed. But already, it’s causing controversy, with proponents saying the extra analytics will help improve strategy and performance, and detractors saying the Minority Report-style predictive analysis will ruin the spontaneous nature of gameplay.

6

Blue Jay

Developing a drone for your healthcare

Have you already found out about student teams at the TU/e? Well, the amount of student teams is increasing and the teams are gaining more and more interest and attention from the outside world.

So, student teams are hot! Now, we would love to share the ins and outs of team Blue Jay Eindhoven.

It’s all about drones Blue Jay Eindhoven consists of nineteen students with different study backgrounds and coming from all over the world. However, we all have one thing in common: next to the daily routine of following courses and enjoying the student life, we are highly motivated to put the theoretical knowledge we perceive around the TU/e campus into something real that is creative, innovative and unique.

Our story started two and a half years ago. Blue Jay was originally found to organize world’s first Drone Café in honor of the 60 years Lustrum of the TU/e. Great chance that you have seen it, but in this café people could order drinks which were served by drones. The drone’s eyes showed the guests that the order was understood and it took off to get the drink. The concept was playful, but with a strong message: drones can be safe, helpful, autonomous and interactive.

Drones today are part of a public debate where they are often seen in a negative way, such as the fear of war drones and violations of privacy. At Blue Jay, we believe technology should serve as a tool for positive change and should help people improve their quality of life; we strive to show the great opportunities and benefits drones can bring to society.

Our goal is to develop an indoor, autonomous drone that can function as an assistant in healthcare. Our drone sets itself apart from other drones in the market, which are mainly deployed for outdoors applications and engage in limited user interaction. The development process is based on user centered design, where we aim to understand the needs of users, their goals, and the

environments they are part of. This iterative, collaborative process will allow us to build a drone that actually matches user needs and can be implemented seamlessly in hospitals and healthcare facilities in the future.

Mechanical Challenges Since you’re probably (almost) a mechanical engineer, there are several challenges to be tackled that may catch your interest.

Reducing noise If you have ever flown a drone yourself this is probably the first thing you notice: the annoying buzz coming from it. When flying outside this noise gradually disappears when flying higher and further away and therefore is not that big of a problem. Flying indoors however does not grand this ability. The drone will always be flying around eye height and when it moves away from one person it will probably run into another. Next to that, the presence of walls will increase the noise level since it is being reflected. For these reasons noise reduction is one of our biggest challenges. The first step in tackling this problem is choosing the right propellermotor combination. We have tested twelve different propellers in combination with different motors and compared them on thrust, efficiency and noise in order to come to the right combination for our drone. One thing we concluded from these tests is that larger propellers are more efficient. But using larger propellers of course also has a down side which is that it makes the drone bigger. For this, however, we found a solution. Instead of using a standard quadcopter we decided to change to a hexacopter. Dividing the propellers into two levels which are partially overlapping made

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Simon Ster 49.3 | March 2018

it possible to maintain the same diameter of the drone while increasing the diameter of the propellers from 8 inch to 10 inch.

Next to having an effect on efficiency this also affects the noise produced by the drone. Since the change in configuration has very little effect on the total weight of the drone each propeller has to produce less thrust in order to keep the drone hovering. This means that the propellers will rotate on a lower rpm which leads to a lower, more pleasant sound.

Saving Weight As with all applications in aerospace engineering weight is a major challenge. No matter what you design it will always be too heavy.

Less weight will lead to longer flight times, higher efficiency and less noise production. For these reasons weight is always a crucial design parameter. The first change we made in the design in order to reduce the weight was changing the placement of the electronics. In the drones designed by the previous teams the electronics were all placed in a structure in the center of the drone.

These drones also had a ring around the propellers to make the drone safe to touch. We decided to combine these two elements of the drone by placing the electronics inside the ring. This will save us the weight of the central structure. Another advantage this brings is that the propellers can be moved further to the center of the drone which leads to a smaller diameter. Next to changes in the design also choosing the right materials has a huge impact on the weight of our drone. To keep the drone from vibrating materials have to be selected with a high specific modulus (or stiffness to weight ratio) like carbon fiber. The disadvantage of carbon fiber however is that it is expensive and very difficult to manufacture.

For these reasons we decided to make some parts out of balsa wood which has a specific modulus close to that of carbon fiber, is affordable and is easy to manufacture.

the fingers and the object. Because of this larger area less force is required to obtain a good grip on an object. In addition to this we use a tape which is inspired by geckos. It consists of tiny hairs which use van der Waals forces to provide the required adhesive strength. This however can only be used to its full potential when applied to a smooth surface such as the screen of your mobile phone.

That’s how we roll Hidden away on the TU/e campus, we have our own office in the Momentum Building. We share the building with other student teams, which creates a place full of innovation but at the same time it is very studentlike (for your information: the kitchen is always a mess and beers can be found in every office). Here, we are daily working hard to reach the milestones and goals.

The team consists of different subteams, Software, Mechanics, Electronics, Interaction Design and Management which work all closely together to make sure that all innovative ideas will be included in the design and development of the new drone prototype. Next to all the working hours at the office, we also get the chance to present our project to the outside world at events and fairs. This year we already went abroad two times, to Berlin and Frankfurt, which was of course an great experience!

So, are you ready to be challenged, excited to work together closely with other students and crazy about drones? Then you are all we’re looking for! We never got enough mechanical engineers so don’t hesitate to get in contact by sending an email to info@ bluejayeindhoven.nl or pass by the office in the Momentum building any time you want. See you!

The ring around the propellers has such a complex shape that we decided to 3D print it. This makes it possible to have a prototype within a short time which leaves more time for testing. Printable materials are however not optimal since they are relatively heavy and have a non-uniform strength. To stay within the weight budget without giving in on strength a honeycomb structure is used here.

Gripper design Unique about our drone is that is has a gripper. Using this gripper the drone can transport objects like an apple or a soda can. In order to be able to pick up as many different shapes as possible we make use of special gripper fingers. These fingers are based on the Fin Ray effect. Due to this effect the gripper fingers adapt to the contours of the object which enlarges the touching area between

Website: www.bluejayeindhoven.nl Email: info@bluejayeindhoven.nl Facebook/twitter/Instagram/snapchat: @bluejayehv

8

Hockey

And everything you need to know about it

You enter the shooting circle, raise your stick, hit the ball and… too bad, the goalie blocks the shot with his leg guard. This is, of course, an article about field hockey.

Daan van Boekel Aristotle a hockey player?

Hockey has been around for ages. The ancient Greeks already passed around a ball using a horn, drawings of hockey have been found in pyramids and in India a hockey-like game has also been around for a long while. It is commonly thought that field hockey originated out of ice hockey, due to ice hockey players having to resort to the grass in the summer. It is however the other way around, ice hockey developed separately in Canada. The game as we now it now has its origin in England, in the early 19th century.

It was played at schools and the first club was founded in London in late 19th century.

We Dutchies had some odd rules in the beginning. The ball we used was soft, teams were mixed and the stick had two flat sides.

International matches were impossible as not a single country had similar rules. To participate in the Olympics in 1928 we had to adjust our rules to the international standards. To everyone’s surprise we became the runner up and hockey gained a lot of popularity all of a sudden.

Year

What

1891

Introduction of hockey in the Netherlands

1892

Founding of the first hockey club A.H.&B.C. in Amsterdam

1895

First match for the Dutch championship

1898

Founding of the predecessor of the KNHB, the NHBB

1908

Hockey becomes an Olympic sport

1910 1928 1980 1984 1996

Woman are allowed to become member of a hockey club The Netherlands participate in the Olympics for the first time Woman’s hockey officially becomes an Olympic sport The Dutch female team wins gold on the Olympics for the first time The Dutch male team wins gold on the Olympics for the first time

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Simon Ster 49.3 | March 2018

So how does this game work again?

There is a definite chance you can just skip this paragraph. As just over a quarter of a million people in the Netherlands play field hockey in the Netherlands, at least one in sixty of us should be familiar of the rules. Not surprisingly, hockey is most played in het Gooi. It is the sixth most played sport in the Netherlands and soccer is, of course, number one. But just to be sure, let us go back to the beginning, what are the two most striking differences with other sports? I am assuming here that you have some general knowledge about hockey and that you know hockey players are not kicking the ball around.

Back in the day all hockey sticks were made of wood, but more and more advanced composites are now used. These allow the stick to be hollow in some spots and therefore lighter and stronger in other spots. The head needs to be very strong, but some other parts can be quite soft. Defenders often use heave this than attackers. The defenders want to be sure to stop the ball, where attackers have to be quick and versatile. The hardest part of the stick is on the side, above the curl. This is where you hit the ball with your backhand. As the point of impact is only small one can hit the ball quite hard, but also less accurate.

From green to blue Let us start with the penalty corner, this is really what sets hockey apart from other games. It is awarded when the defending team makes an offense in the circle or an intentional offense in the 23-metre area. During a penalty corner only four defenders (excluding the goalie) are allowed in the goal, behind the back line. The rest of the players have to be behind the middle line.

An attacker plays the ball from behind the back line towards his teammates outside of the circle. If the ball has been outside of the circle, the attackers can make an attempt on goal (an attempt has to come from within the circle). When this ball is passed, however, the defenders are allowed to run out of their goal. The attackers tend to use the drag flick, which can reach speeds of over 120 km/h. There is no point in trying to explain how that works, I recommend you to look it up.

Then there is the self-pass which is allowed since 2009, so still a very new rule. Whereas first you had to pass the ball to a teammate after bringing the ball back in the game, it is now allowed to play the ball to yourself, so start a dribble.

Hockey was always played on regular grass, but now three sorts of pitches with artificial grass are used. First of all there are sand filled fields, the sand evens out the surface and allows the ball to go smooth. These fields have the longest fibers which are the least densely packed. Then there are water based fields, which are very densely packed and use water to even out the surface.

They require an irrigation system, usually the field is sprayed after every half of the game. In between there are sand dressed courts, they have reasonable dense fibers, so they require only a little sand compared to sand filled fields.

With the introduction of the artificial fields came the difference between India and Pakistan and the Western world. The cheapest artificial pitches are over â‚Ź50.000,-, which in India and Pakistan was a lot harder to gather. Since in the Netherlands this was easier to finance, a difference in experience on these improved pitches grew, and thereby a difference in international success.

Sticks and stones Where Toetanchamon may have used sticks and stones, nowadays the material is way more advanced. First of all the balls, these are hollow and have dents on the outside, just like a golf ball. The purpose is also the same as with a golf ball. These tiny dents trap air on the outside and air on air has less friction than air on plastic, thus making the ball go faster.

Variants of the game We all know ice hockey and cricket, but there are some other sports which have some similarities to field hockey. There is indoor field hockey, which has very different rules and even uses different sticks. It is not allowed to hit the ball, only to flick it. Underwater hockey is another variant of the game, which uses very short sticks and a puck that sinks. In Ireland hurling is very big, this is a game which can be seen as a combination of hockey and American football. I definitely recommend watching it sometime, it is a very fast game.

10

Zweefvliegen

Een uitleg door de ZES

De Zweefvliegclub Eindhovense Studenten biedt studenten al een vliegende start sinds 1963. Je leert om bekwaam te zweefvliegen, waar je vanaf de eerste les al de controle over het zweefvliegtuig neemt! Maar hoe werkt dat zweefvliegen nu eigenlijk en welke technische aspecten komen daar bij kijken?

Edward Hyde Voor het zweefvliegen heb je vier dingen nodig; een kist ( jargon voor zweefvliegtuig), lier, mensen en een beetje goed weer.

Allereerst komt een piloot met z’n kist zonder de hulp van een aanhaker, lierist, trekker rijder, instructeur en startleider natuurlijk niet de lucht in. Maar dit is natuurlijk niet zo interessant voor jullie, toch? Daarom een kleine indruk van de technische aspecten van het zweefvliegen:

wilt de hoogte van de thermiek weten? Hier volgen twee simpele doch effectieve methodes voor een snelle inschatting: 1.

Men neemt van het weerbericht de maximum temperatuur en het dauwpunt klakkeloos over. Trek de dauwpunttemperatuur van de maximale temperatuur af. Vermenigvuldig dit getal met 120, wat een ruwe schatting geeft van de wolkenbasis.

De interactie tussen de lierist, het zweefvliegtuig en de piloot via de lierkabel brengt je uiteindelijk de lucht in. Nou zou je jezelf natuurlijk af kunnen vragen als degelijke werktuigbouwer; hoe groot zijn de krachten tijdens zo’n lierstart? Eerst accelereert het vliegtuig razendsnel naar 100 km/u binnen 3 seconden, waarbij onze BUSIO lier, met als tractie een DAF truck, een vermogen van 115 kW (157pk) nodig heeft. Hiervoor moet de lierkabel natuurlijk sterk genoeg zijn. Daarvoor gebruiken wij Dyneema met een treksterkte van zo’n ZEStien kN. Voorheen gebruikten wij hiervoor staalkabel, maar als deze brak was het een hels karwei deze weer aan elkaar te ‘splitsen’.

2.

Teken/print een grafiek met hoogte vs. temperatuur in °C met daarin de droogadiabaten (afkoeling per 100m stijgende lucht). Teken nu vanaf de maximumtemperatuur een lijn die de droogadiabaat volgt. Teken daarnaast de lijn door de hoogtetemperaturen, de toestandskromme. Het snijpunt van de gevolgde droogadiabaat en de toestandskromme geeft de hoogte. Zie ook het voorbeeld van Figuur 1.

Als de lierkabel rechtstreeks aan het vliegtuig aangesloten zou zijn, zou er in het geval van overbelasting (denk aan zware turbulentie) een grote kans zijn dat het zweefvliegtuig breekt. Om dit te voorkomen is er het zogenaamde breukstukje. Worden de krachten te groot, dan breekt dit breukstuk en zo wordt schade aan het vliegtuig voorkomen. Voor onze eenzitters gebruiken we hiervoor een blauw breukstukje die breekt bij een kracht van ZES kN, voor de tweezitters wordt doorgaans het bruine breukstukje gebruikt met een breuksterkte van 8,5 kN. Eenmaal afgehaakt van de lier komt de eeuwige zoektocht naar thermiek. Hoewel de meeste van ons inmiddels thermodynamica hebben gevolgd, is thermiek helaas niet in detail aan bod gekomen.

Schande! Hopelijk hebben jullie al enig idee van wat thermiek is, hoe dan ook volgt hier een interessante samenvatting met insider info.

Nederland is een winderig land, deze wind voorziet tegenwoordig gelukkig ook een groot aandeel van de energiebehoefte. Natuurlijk zijn er ook verticale luchtbewegingen, een geheim onder vogels en zwevers. Deze opstijgende lucht wordt thermiek genoemd.

Thermiek ontstaat doordat de zon het aardoppervlak verwarmt, dit verwarmde deel verwarmt op zijn beurt weer de lucht hierboven. Men realiseerde zich dat thermieksterkte afhangt van vele factoren zoals zonnestand, soort aardoppervlak, omringende temperatuur, windsterkte enz. Stel nu dat je wilt gaan vliegen en je

Hoogte vs. temperatuur, waar men de wolkenbasis mee kan schatten.

In het echt zal de thermiek vaker iets hoger komen, doordat de thermiek droge lucht met vochtige lucht laat mengen. Hierdoor daalt de dauwpunttemperatuur iets en dit geeft wat extra hoogte aan de basis.

Hopelijk heb je nu een iets betere indruk van zweefvliegen.

Maar belangrijker, hopelijk heb je nu een klein van de technische aspecten die hierbij komen kijken. De combinatie van deze techniek op verschillende vlakken en natuurlijk het vliegen zelf maakt het tot een fantastische sport.

Contact: Z.E.S. Web: www.zweefvliegen.nu Email: info@zweefvliegen.nu Facebook: facebook.com/zweefvliegen.nu

12

URE

Educating the Engineers of the future

At URE we design, build, test and race a new electric race car every year. And not just a race car, but one that accelerates from 0-100 km/h in 2.3 seconds and weighs only 195 kilograms. Needless to say, a great amount of mechanical engineering knowledge is gathered and applied in this project. Besides building a new electric car, there is another interesting project we are working on this year.

Each summer, URE participates in the Formula Student competition.

This is world’s largest engineering competition. In events all over the world, teams from different universities are gathering to compete in different static and dynamic events. A full year of team dedication is rewarded with exciting days of defending the design against judges from the automotive industry and racing the freshly built car against other international top teams.

How does it work at URE? A typical year at URE starts in September, when the new team is formed, consisting of part-time as well as full-time members.

To keep a team of over 60 members manageable, it is divided into different departments, including Aerodynamics, Chassis, Control and Powertrain. These departments are always filled with enthusiastic mechanical engineering students who want to do more than just digest the several lectures their study offers.

Designing a part of the car gives you a great opportunity to really apply -and greatly expand- the knowledge you’ve obtained in

courses. It is very satisfactory to see your design become reality in the production phase, which starts as soon as October with for example the production of the self-developed carbon-fibre monocoque.

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Simon Ster 49.3 | March 2018

Aerodynamics

Driverless

What makes URE special is that almost every single part of the car is self-developed. From the driver’s seat to the battery pack or the suspension brackets, every component is optimized to obtain the lightest, fastest car possible. To get a better feel for what designing a part is like at URE, let’s hear from Pascal Ruwen, a third-year mechanical engineering student who has gained quite some experience in aerodynamics.

As autonomous driving is the future, and the Formula Student Germany event has added a driverless competition, URE has decided to build a fully autonomous race car next to our ‘ordinary’ electric race car. This gives us a great new opportunity to be involved in and help developing the latest state of the art technologies.

Dennis De Niel, currently team manager, has completed his final bachelor project on the subject last year. He worked on the environment sensing system (track detection). What better way to get to know about driverless than to hear from one of URE’s pioneers in the discipline.

“The aerodynamics department is responsible for the airflow around the car. We influence this flow with two main purposes.

The first one, very evident when looking at the car, is to produce downforce. Downforce is an extra vertical load produced when driving, providing grip to the tires for higher cornering speeds.

The reason why this downforce is needed for optimal vehicle performance is due to its effectiveness; it provides a high extra load on the tires (a lot of extra grip) for a relatively small weight increase. The second purpose of the aerodynamics is to provide cooling flow, needed to cool almost every component of the powertrain. This means that the large sidepods found on the URE race cars are not there to make the car look like a jet fighter, but to provide a good mass flow of air to the radiators.

To start the design process, the needed performance must be defined. This is determined through lap time simulation of multiple parameters, like the downforce, drag and weight. A maximum drag constraint exists, which is the maximum drag for which the battery lasts an entire race. With the needed parameters known, the interesting work can begin, namely the design and simulation of concepts. Designing the aerodynamic components is fully done using the CAD software NX. Ansys Fluent, a commercial Computational Fluid Dynamics package, is used for simulation of the components. Usually, each component goes through 20 to 60 design iterations before the final solution is found. When the CFD work is completed, the challenge of structural design starts. The theoretically ideal geometry must be fully detailed, including a production plan, carbon fibre lay-up and mounting points. In this phase, the design really starts to come alive, as the final CAD model is transferred completely onto the car once all the components are made.

As mentioned above, most of the design work involves simulation using finite element analysis. Although one would think advanced knowledge of FEA and fluid dynamics is needed to work in the aerodynamics department, this is not the case in practice. Most of the aerodynamic knowledge is self-taught through books and academic papers, while the simulation knowledge is transferred by partners and team members. This makes the aerodynamics department a very accessible department, where simply working hard and using creativity can yield great results.”

Simulation software

“As this was completely new for URE and there was no existing algorithm, it was really nice to start from scratch. A few of my elective courses were part of the Video Coding Architecture group, which already gave me a kick-start. Also using results from literature research, I was able to design some algorithms and test them on the car. The URE11 -the car which we will make autonomous- is still capable of driving manually. Therefore the URE11 can provide footage we use to test and improve our algorithms. Currently, our algorithms are optimized on the car using a stereo camera and a lidar sensor is added to make the track detection algorithm more robust.”

These are just a few examples of what different members at URE achieved. Are you looking for a challenge? Enthusiastic students from all years are always welcome to help push the boundaries of engineering! As most of our team members are part-time the team consists of a variety of students from all years and different disciplines.

Opportunities exist in the form of part-time assignments, end projects and sometimes even internships. Do you want to challenge yourself and gain valuable practical experience?

Visit our website at www. universityracing.nl or contact us through universityracing@tue.nl

14

Hephtig: Referendum

Wet op de Inlichtingen- en Veiligheidsdiensten

Tegelijk met de gemeenteraadsverkiezingen wordt op 21 maart een referendum gehouden over de Wet op de inlichtingen- en veiligheidsdiensten, vaak de ‘sleepwet’ genoemd. Wat houdt die wet in en wat betekent het referendum?

Lennard van Damme Wellicht voorlopig het laatste referendum Referenda zijn in Nederland altijd ongebruikelijk geweest. Voor het referendum over de Europese grondwet in 2005 was nog een speciale wet nodig om dat referendum mogelijk te maken, maar in 2015 trad de Wet op het raadgevend referendum in werking.

Op grond van deze wet kunnen burgers referenda aanvragen over wetten en verdragen die door de Tweede en Eerste Kamer zijn aangenomen, maar nog niet in werking zijn getreden. Op grond van deze wet is tot nu toe één referendum gehouden, over het associatieverdrag met Oekraïne. Het huidige kabinet is echter voornemens om de referendumwet zo snel mogelijk weer af te schaffen. Het referendum over de sleepwet, nog maar het derde in de Nederlandse geschiedenis, zou dan ook wel eens voorlopig weer het laatste landelijke referendum kunnen zijn.

Wat houdt de sleepwet in?

Ten eerste is het belangrijk om op te merken dat er al een Wet op de inlichten- en veiligheidsdiensten (Wiv) is: de Wiv 2002. De wet waar het referendum over gaat is de Wiv 2017, en deze wet trekt de Wiv 2002 in. Als de Wiv 2017 dus niet doorgaat, dan blijft de Wiv 2002 gewoon van kracht. Daarom wordt in dit artikel alleen gekeken naar de verschillen tussen de twee.

Sleepnet Het meest prominente verschil met de Wiv 2002, of in ieder geval het verschil dat de meeste aandacht heeft gekregen, is de uitbreiding

van de bevoegdheid een zogenoemd ‘sleepnet’ in te zetten. Onder de Wiv 2002 mogen de diensten vrijelijk slepen door alle draadloze telecommunicatie.

Deze bevoegdheid was oorspronkelijk vooral bedoeld voor met name radioen sattelietcommunicatie. Door de enorme expansie van draadloze telecommunicatie sinds 2002 is hier ook alle mobiele telefonie en mobiel internetverkeer onder gaan vallen. De diensten mogen deze communicatie dan ook ongericht verzamelen en opslaan.

Voor analyse van deze communicatie is toestemming van de minister nodig.

Wie zijn ‘de diensten’ en ‘de minister’?

‘De diensten’ zijn de Algemene Inlichtingen- en Veiligheidsdienst (AIVD) en de Militaire Inlichtingen- en Veiligheidsdienst (MIVD).

‘De minister’ is de Minister van Binnenlandse zaken waar het de AIVD betreft en de Minister van Defensie waar het de MIVD betreft.

Deze sleepnetbevoegdheid wordt onder de Wiv 2017 aanzienlijk hervormd. Ten eerste wordt de bevoegdheid uitgebreid naar álle vormen van telecommunicatie, dus ook vaste telefonie en internet. Hier staat echter tegenover dat het sleepnet niet langer ongericht mag worden ingezet. De diensten mogen dus onder de Wiv 2017 niet meer in het wilde weg telecommunicatie onderscheppen.

Per de Wiv 2017 mag het aftappen van telecommunicatie alleen nog onderzoeksopdrachtgericht gebeuren. Een dergelijke

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onderzoeksopdracht krijgen de diensten van de minister. Dit kan bijvoorbeeld betekenen dat de AIVD de opdracht krijgt om een vermeende terrorist te vinden die zich ‘ergens in Woensel’ bevindt.

De AIVD mag dan alleen nog maar telecommunicatie van en naar Woensel aftappen, maar hoeft zich niet meer te beperken tot draadloze communicatie. De diensten hebben onder de Wiv 2017, in tegenstelling tot onder de Wiv 2002, bovendien de toestemming van de minister nodig voor de inzet van een sleepnet. Er komt dus een tweede controlemoment.

Als de diensten een sleepnet inzetten, dan worden daarmee heel veel gegevens verzameld en opgeslagen. Deze gegevens zijn dan echter nog niet onderzocht. Voor dit onderzoek is aparte toestemming nodig van de minister. In het verzoek om toestemming moeten de diensten aangeven wat voor onderzoek ze willen doen in de gegevens en hoe en waarom ze dat willen doen.

Impliciet wordt Expliciet Een andere verandering in de sleepwet is dat veel van de bevoegdheden die de diensten onder de Wiv 2002 slechts impliciet hadden, in de Wiv 2017 expliciet vermeld worden. Het gaat dan bijvoorbeeld om de bevoegdheid tot hacken, het verzamelen van DNA, het gebruik van informanten en het toepassen van geautomatiseerde data-analyse. Deze bevoegdheden staan dus voor het eerst in de wet, maar zijn daarmee niet nieuw.

In de Wiv 2017 worden aan veel van deze bevoegdheden voorwaarden gesteld. Zo mogen bijvoorbeeld niet alle gegevens geautomatiseerd worden geanalyseerd. Het is de diensten bijvoorbeeld alleen toegestaan om met een sleepnet verzamelde telecommunicatie geautomatiseerd te analyseren als daarvoor toestemming is gegeven door de minister. Bovendien kan de inhoud van deze telecommunicatie nooit geautomatiseerd worden geanalyseerd, alleen de metadata. Ook voor het hacken en verwerken van DNA is voortaan toestemming nodig van de minister.

Toetsingscommissie De nieuwe bevoegdheden van de diensten brengen de nodige bedreigingen voor de privacy met zich mee. Vooral de mogelijkheid van een sleepnet voor niet-draadloze telecommunicatie vergroot de mogelijkheden van de diensten om burgers te observeren.

Mede hierom wordt in de Wiv 2017 een toetsingscommissie opgezet. Deze toetsingscommissie heeft als taak het controleren van de toestemmingen die de minister geeft. Bij veel van de nieuwe of geexpliceerde bevoegdheden is de ministeriële toestemming voortaan onderworpen aan het oordeel van de toetsingscommissie. Dit geldt bijvoorbeeld voor de inzet van een sleepnet, het onderzoeken van de resultaten van een sleepnet, hacken en het verzamelen van DNA. Het geldt ook voor sommige oude bevoegdheden, zoals het binnentreden en het plaatsen van afluisterapparatuur in woningen. Voor sommige bevoegdheden, zoals het binnentreden en afluisteren van bedrijfspanden, blijft toestemming van alleen de minister voldoende.

De toetsingscommissie gaat bestaan uit drie personen. Ten minste twee van de drie commissieleden moeten minstens zes jaar ervaring hebben als rechter. Elke keer als de minister een dienst een toestemming geeft die onder de toetsing valt, dan kan de dienst zijn bevoegdheid pas gaan uitvoeren nadat de toetsingscommissie heeft geoordeeld dat de toestemming terecht is gegeven. In spoedeisende gevallen kan de dienst al eerder beginnen, maar mocht de toetsingscommissie in zo’n geval oordelen dat de minister ten onrechte toestemming heeft gegeven, dan moet de dienst de werkzaamheden direct stoppen en alle reeds verzamelde gegevens vernietigen.

Voor veel van de bevoegdheden van de diensten betekent dit dat er niet langer alleen toestemming nodig is van één minister, maar ook van twee rechters.

Uitwisseling In de media is de nodige aandacht geweest voor de bevoegdheid om gegevens te delen met buitenlandse inlichtingendiensten.

Vooral het feit dat de diensten gegevens mogen delen vóórdat ze zijn geanalyseerd, en de diensten dus niet precies weten wát ze delen, is kritisch ontvangen. Ook voor deze bevoegdheid geldt echter dat die niet nieuw is. Wat nieuw is, is dat hier nu toestemming van de minister voor nodig is. Het onderling delen van informatie is een al lang bestaand gebruik. In de Wiv 2017 wordt deze bestaande bevoegdheid geconcretiseerd. Zo is onder andere een lijst met criteria opgenomen waar buitenlandse diensten aan moeten worden getoetst voordat er kan worden samengewerkt. Met diensten die niet aan die criteria voldoen kan alleen worden samengewerkt als dit noodzakelijk is voor de Nederlandse nationale veiligheid. De diensten mogen onder geen enkele omstandigheid buitenlandse diensten helpen bij het verzamelen van gegevens in Nederland.

Referendum Op 21 maart worden deze veranderingen in de wet voorgelegd aan het Nederlandse volk. Referenda zijn in Nederland echter altijd slechts raadgevend. De wetgever is alleen verplicht rekening te houden met de uitslag van het referendum, maar wat dat betekent, mag de wetgever zelf weten. Gezien de belangen die er op het spel staan, alsmede de gebrekkige informatie waarop de gemiddelde kiezer zijn stem baseert is het vrijwel zeker dat de Wiv 2017 doorgaat, ongeacht de uitslag van het referendum. Het referendum bepaald dan ook niet echt of de Wiv 2017 er komt, maar vooral wat de politieke prijs van deze wet gaat zijn.

Wie mogen er stemmen?

Voor het referendum mogen alle Nederlanders van 18 jaar en ouder stemmen.

Voor de gelijktijdige gemeenteraadsverkiezingen mogen alle Europeanen die in Nederland wonen stemmen, alsmede alle niet-Europeanen die al minstens vijf jaar legaal en onafgebroken in Nederland wonen.

16

Company visit

A visit to NTS-group in Eindhoven

The NTS-group is a company that specializes in developing high-precision systems, modules and components for the high-tech industry. Their customers include company’s as big as ASML. They are located in the US, the Czech Republic, Singapore and Shanghai. We went to visit their headquarters and mechatronics systems department here in Eindhoven.

Cas Dijsktra The company visit consisted of a case, based on an actual assignment they had done, and a tour through the company, where they showed us some of the projects they were working on in the mechatronics department.

The Case After a short introduction, the case we would be doing was presented. It was based on a real assignment they had gotten from ASML and Zeiss. Zeiss makes lenses which ASML uses in their machines. These lenses need to be transported, but the problem is that they are very fragile. In order to ensure that they remain intact, a special carriage has to be designed which can carry the load of these 2000kg lenses and absorb any shocks that may occur during transport using a system of springs. Because of the desired size of the shipment the maximum allowed deflection of the spring was only 15cm. The customer had decided that the load shouldn’t accelerate at more than 1g. Performing the necessary calculations, it was found that this was an impossible objective. Declining the customer’s request was not an option.

Therefore, a solution had to be found that complies with the client’s wishes, although a compromise may be necessary. In this case the size of the shipment would have to be increased, for a greater maximum spring deflection to be allowed. Finally, they presented us their own solution. Because these lenses are so fragile and precise, even the slightest pollution could have a devastating effect, thus the construction was build and tested in a clean-room.

The tour After the case and a short break it was time for a tour through the company. First we got to see the clean-room, where men in white suits and hairnets were working on the assembly and testing of high-precision microscopes, which are used in hospitals. The next location we entered was a large factory hall, where different corners were dedicated to different projects. It was explained to us that, because they take on so many different assignments, it was important that they could alter the arrangement of the room according to the active projects at any given time. While walking through the assembly hall, we stopped a few times to watch current products which were development at that moment. They showed us a new type of 3D-printer, which is able to print steel.

This is relatively new technology that companies are now starting to try out. Besides the 3D-printer, they also displayed a prototype machine that would be used as a large vending machine for medicine in hospitals.

Having seen these projects we were now also given some insight into the management part of the organization. As this is a rapidly growing company, it is important but also difficult to properly manage and organize everything. NTS-group has an entire section filled with whiteboards, where planning and organization are structurally displayed. They also survey the cooperation between production and design and as a motivational tool they measure the turnover made using a tube filled with ping pong balls. It measured over 210 million.

The tech industry is booming world-wide and Eindhoven is booming with it. NTS-group is in the middle of it all. They produce complex solutions for some of the most notable tech-companies world-wide. It is a well-organized, important company and will surely keep expanding over the coming years.

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18

Course Evaluations

Jerome Seelen

Quartile two has come to an end and we will look back on what happened in this quartile concerning education. A lot of feedback is given and some changes to the course have been made to make sure the Mechanical Engineering student will be the Engineer of the future.

A coherent package within Mechanical Engineering will not continue in the upcoming years. Multi-level Control in Manufacturing Systems will no longer be available for students. 4AB10 Introduction multi-level control in Manufacturing Systems in quartile four will not start again. The coherent package will not continue due to the low amount of participating students with respect to the time investments of the teachers. This in combination with the disappointing evaluation scores. Students that did not pass the course can still do a resit next year.

The First Year Student Council has started. A lot of good input has been delivered by the students and much is already achieved with the given feedback. The tutoring at Calculus was received really different from different groups. For next year the TU/e will look at making a manual for tutors to give the best for their group. Another problem was that the new study advisors were not yet known by the students. The problem was adressed to the quality assurance coordinator, Alexandra Nicolaije, and the study advisors will introduce themselves in the next information lecture for the first year students. These are a few examples of what is achieved, but there is much more achieved and there will be even more achieved in the upcoming months. But we need you in the Student Councils. Do you think you have improvements for different courses, Canvas, Osiris or StudyStore, mail onderwijs@simonstevin.tue.nl, call to the Simonkamer or pass by at the Simonkamer. Because we need you to keep improving the education.

This percentage represents the amount of students that filled in the course evaluation relative to the amount of students that took the course.

This is the average score given to the course by the respondents.

An upward pointing arrow indicates an increase compared to last year. Downwards indicates a decrease and a circle indicates no major changes.

This indicates the average amount of hours spent on the course by the respondents of the course evaluation.

Green symbols indicate scores above the goal, yellow symbols indicate sufficient scores under the goal, red symbols indicate insufficient scores.

Modeling of Dynamical Systems

Model-Based System Engineering

Hydraulic turbomachines

Feedback: • Defining an own goal is well received by students • Quality of the set-ups / measurement equipment can be improved • Support on recommended prior knowledge can be a point of attention

Feedback: • Good combination of theory and applications • Ideally the start of the project begins earlier • In the lectures: more focus on examples of applications • Students like the projects

Feedback: • Clear lectures and good explanation • Good combination of theory and practical applications • Quality of guest lectures can be improved

Improvements: • The set-ups are good, but some students did not use it in a well thought manner which resulted in failures/break-down. Gerard van Hattum will improve his supporting lecture next year.

• The comments of prior knowledge comes most from pre-master students, but the results show no difference, so no action is taken. The Program Committee agrees

Improvements: • This year the intermediate tests are replaced by a project which is well received • Quizzes and peer evaluations are introduced and are well received by the students as well • Focusses for next year are: more focus on examples of applications in lectures and more time for the project

Improvements: • Try to reduce the overlap between guest lectures and regular lectures • Improvements from last year are: 1.

2.

Book contains more assignments / answers.

A document is created to help students transform the American notation to the notation the students are more familiar with.

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Movable Bridges

Simon Ster 49.3 | March 2018

And risk assesment

Within the Netherlands, there are hundreds of movable bridges located throughout the entire country. These bridges are owned by several authorities, like Rijkswaterstaat, ProRail, provinces, municipalities, but also water boards. These bridges should be considered as a machine with large, moving parts and therefore they can be assessed by means of the Machinery Directive (2006/42/EG). The main goal of this directive is to establish that these machines comply with the so-called essential health and safety requirements. In other words, the movable bridges in our country need to be safe.

Risk assessment The first phase is performing a risk assessment according to ISO12100. A common method is the use of the 14 points risk assessment method, as schematically shown in Figure 1. In this method four factors are taken into account; severity of the occurrence, frequency or exposure time, probability of the occurrence and the possibility of avoidance. As a possible scenario we take into account the hydraulic actuators of a movable bridge as can be seen in Figure 2. This scenario involves a mechanic performing maintenance near the actuators, at this point the bridge starts to open and the mechanic gets crushed by the actuators or the counterweight. In this case the risk would result in possible death of the mechanic, so the Severity = 3. Maintenance is performed several times per year, therefore the frequency is low (1). If the mechanical installation is unsafe the probability of the event is high (3). When the event takes place the mechanic has no chance of avoiding the danger so Avoidance = 2. This results in a risk score of 12, which means this is a very high risk. This process is repeated for all possible risks found on a bridge and the risks with the highest scores are to be addressed as soon as possible.

around the cylinders so they can no longer be reached. However for maintenance they need to be accessible for mechanics, therefore a solution using industrial automation can be chosen. With this method detectors can be placed around the cylinders. When someone is present around the cylinders the computer blocks all movement of the bridge. When choosing the organizational approach, procedures are laid down, for example, it is not allowed to operate the bridge when a technician is present. The use of personal protective equipment also belongs to the organizational approach. This approach is not preferred, and is therefore only used if other methods are not possible.

Figure 2: Hydraulic actuators of a movable bridge

Projects

Figure 1: 14 points risk assessment method

Improvement measures When designing improvement measures, we always work according to the following order; 1. Source approach 2. Collective approach 3. Organizational approach.

Using the source approach, the hydraulic actuators should be removed and the bridge converted into a fixed bridge. This is however impossible because the fixed bridge would be an obstacle for the water transportation sector. Within the collective approach, a mechanical or a industrial automation solution can be chosen. With the mechanical approach, a physical barrier is placed

Two projects involving risk assessment of infrastructural objects are IMPAKT and inspection of infrastructural objects in Overijssel.

For Rijkswaterstaat we performed inspections of all electrified objects focussing on physical security, cyber security, functional safety and asset management (IMPAKT). For the province of Overijssel we inspected all movable bridges and all locks by means of the Machine Directive. In both projects a risk assessment was performed and improvement measures are suggested. Has this sparked your interest then join our business course IMPAKT or take a look at our website: http://www.witteveenbos.com/

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Team FAST

Replacing fossil fuels

We are Team FAST (Formic Acid Sustainable Technologies), an enthusiastic, multidisciplinary student team of the Eindhoven University of Technology. We have took up the challenge of introducing a revolutionary sustainable fuel called Hydrozine.

Right now now we are creating a system which can convert Hydrozine to electricity.

In total 28 students are working in different autonomous subteams to realize this project. We envision a world with sustainable energy as the standard, without having a negative impact on our society. Team FAST wants to take part in the transition towards a more sustainable world where fossil fuels have no place. We believe in a future where different sustainable energy carriers are used for different applications to allow every sector to become sustainable.

How? Hydrozine is defined as ‘sustainably produced formic acid’.

Hydrozine is a hydrogen carrier and can be used as an energy carrier through fuel cell technology. It can be produced in a circular electrochemical process with water, carbon dioxide and electricity.

Hydrozine is a carbon neutral fuel when atmospheric carbon dioxide is used, or that of a waste source, like biogas.

Simply explained, this is how Hydrozine is produced. Water and carbon dioxide are mixed together in a liquid and when running an electrical current through this liquid, oxygen starts to escape.

The resulting liquid is formic acid in which the energy is stored.

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Simon Ster 49.3 | March 2018

The beauty of this is that the surplus energy, that is generated by renewable energy resources, can be used to create Hydrozine.

This way the energy does not get lost, but instead will be stored within the liquid formic acid. Since the energy is now stored within a liquid, it can be transported to different locations or used at peak-hours. Renewable energy sources, like wind turbines and solar panels, have a fluctuating energy production which makes it hard to match the demand and supply of electricity to society.

One of the greatest challenges of creating a sustainable world is the storage of renewable energy. Hydrozine can help tackle this problem because energy can easily be stored in liquid form. This is helpful when excessive energy is generated or when it is generated at inconvenient locations.

This is how the system should work in theory, however currently the system is not yet operational as Team FAST is still working hard to realize the project. The coupling of the reformer and the fuel cell is a big challenge to be solved this academic year. The output of gasses from the reformer has to be 100% pure, because contamination of the gas going into the fuel cell will harm the fuel cell.

The fuel cell will also malfunction if the temperature of the oxygen in the fuel cell is too high or if a too large amount of electricity is generated within the cell. Thus we are still testing the system nonstop for further development and optimization.

In the last year we have been working on the first system that is able to turn Hydrozine into electricity. Last year we presented one possible application for this system, a range extender(REX) for an electric city bus.

The REX can be attached to the back of an electric VDL bus functioning as a range extending generator that uses Hydrozine as fuel, which can increase a bus’s effective driving range. This year however team FAST is showing a different application of the system. This will be a stand-alone generator and it will be presented this academic year!

Next year a new team will take up the challenge of developing a different application for the Hydrozine technology. This could be anything ranging from a truck to a boat or even a plane if the ambition is big! This will mean building a new system from scratch and implementing it into the chosen application.

Are you interested in working on an innovative high tech system?

Team FAST is still looking for enthusiastic engineers who want to help develop this new application next year or people who want to help finalize the current system. Possible activities range from system engineering and system testing, to arranging the contact with external relations and marketing.

For more information send an e-mail to info@teamfast.nl

The Hydrozine is stored within the system at atmospheric level.

Afterwards the liquid is pumped into the reformer. In the reformer a catalyst, which we develop in house, is used to transform the liquid Hydrozine into the gasses hydrogen and carbon dioxide. The gasses than flow towards the fuel cell. In this cell the hydrogen reacts with the oxygen from the air. Through this reaction electricity is generated that can be used to power any appliance.

Water vapour and carbon dioxide are being emitted into the air after the electricity is extracted. Which are the same components that are used to create Hydrozine. Completing the circle and making this energy carrier carbon neutral.

24

Staut: Cornelis Lely

Ingenieur én staatsman

Het mag geen verrassing heten dat het grootste kunstmatige eiland ter wereld een Nederlandse polder is. De geestelijk vader van het project, Cornelis Lely, voerde 100 jaar geleden de Zuiderzeewet in, waarmee de aanzet werd gegeven voor Flevoland en het IJsselmeer.

Bas Raes Dat Lely van groot belang was bij de droogmakerij van Flevoland wordt nog eens onderstreept door het feit dat de provinciehoofdstad van Flevoland – Lelystad – naar hem vernoemd is. Tegenwoordig kijkt zijn standbeeld uit over de vroegere Zuiderzee vanaf de afsluitdijk. Hoe lukte het deze ingenieur om minister te worden en Nederland letterlijk groter op de kaart te zetten?

De basis Cornelis Lely wordt geboren in Amsterdam als zoon van een gegoede graanhandelaar die op zijn handelsreizen vaak zijn kinderen meeneemt. Hierdoor komt Lely in aanraking met de techniek, wat er uiteindelijk toe leidt dat hij Civiele Techniek gaat studeren aan de Polytechnische School in Delft. Wellicht is hij hier ook lid geweest van het net opgerichte Gezelschap Leeghwater, vernoemd naar die andere beroemde waterbouwkundige.

Hoewel dit laatste ongewis is, is zeker dat Lely in 1875 afstudeerde en in dienst trad bij Rijkswaterstaat. Daar is een grote vraag naar ingenieurs, want in die tijd wordt in Nederland druk gebouwd aan dijken, sluizen en gemalen. Zodoende komt hij ook in aanraking met de politiek als hij meewerkt aan een wet over aan te leggen

kanalen. Tegelijkertijd wordt hij lid van de Zuiderzeevereniging, een groep die propageert voor drooglegging van de Zuiderzee.

Het streven naar afsluiting van de Zuiderzee werd enerzijds gevoed door veiligheidsoverwegingen en anderzijds door economisch belang. De Zuiderzee stond in open verbinding met de Noordzee wat bij storm tot nijpende situaties leidde, vaak met desastreuze gevolgen door het grote aantal inwoners aan de kustlijn. Daarnaast produceerde Nederland minder voedsel dan het gebruikte en door inpolderen kon er meer ruimte gemaakt worden voor het verbouwen van voedsel dat dan niet meer geïmporteerd hoefde te worden.

Het plan-Lely Over de drooglegging van de Zuiderzee werd al jarenlang gediscussieerd en het oudst bekende plan is afkomstig van een zekere Hendrik Stevin, zoon van Simon. Dit plan omhelsde het aanleggen van dammen tussen de Waddeneilanden, waarbij Hendrik zich niet liet beperken door de technische uitvoerbaarheid.

Lely daarentegen begon met de ontwikkeling van een plan dat een stuk haalbaarder was door de keuze om een afsluitdijk te plaatsen tussen Friesland en Noord-Holland. Uiteindelijk presenteert hij in 1891 een plan dat technisch uitvoerbaar is en daarmee valt hij op in politiek Den Haag. De toenmalig minister-president Tak van Poortvliet stelt hem op pas 36-jarige leeftijd aan als minister van Waterstaat, Handel en Nijverheid.

Dit betekent echter niet dat de weg geplaveid is voor de uitvoer van het plan-Lely. Het plan kan rekenen op weinig medestanders,

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Simon Ster 49.3 | March 2018

mede door de grote financiële offers die de drooglegging vergt. De ambitie wordt definitief in de kiem gesmoord als het kabinet-Tak Van Poortvliet valt over de invoering van het algemeen kiesrecht.

Alleen voor mannen welteverstaan, om de tijdsgeest maar even te benadrukken.

Veranderende inzichten Ondanks nog een periode als minister, afgewisseld met zitting in de Tweede Kamer en het gouverneurschap van Suriname, blijft het plan van Lely in de ijskast liggen. Dat betekent niet dat het rustig is, integendeel, door de industrialisatie is het een tijd van grote veranderingen, vooral op sociaal vlak. In de heftige confrontaties tussen werknemers en -gevers moet Lely navigeren naar een voor beide partijen acceptabele oplossing. Met de invoering van de Ongevallenwet vestigt Lely zijn naam als redenaar en politicus, wat hem een populair publiek figuur maakt.

Diezelfde industrialisatie zorgt ervoor dat de welvaart in Nederland significant toeneemt en daarmee de financiële draagkracht van de overheid, totdat dit verstoort wordt door het uitbreken van de Eerste Wereldoorlog. Hoewel Nederland neutraal was in dit conflict had dit wel indirecte implicaties voor het land.

De toevoer van voedsel vanuit het buitenland stokte, resulterend in een voedseltekort. Door het pijnlijk blootleggen van de Nederlandse afhankelijkheid verstomden de financiële bezwaren van tegenstanders.

Een visie voor de automobiel Zoals aangegeven met de sociale wetgeving, hield Lely zich als minister niet alleen bezig met droogmakerij. Tijdens zijn ministerschap was er de opkomst van een nieuwe technologische vinding: de automobiel. Minister Lely zag in dat de auto wel eens een succes kon worden en dat er infrastructuur moest komen.

Daarom ontwikkelde hij in 1915 een rijkswegenplan, dat door de oorlog weliswaar niet van de grond kwam, maar wel de basis vormde voor latere plannen. Dit plan verklaart de, op het eerste oog arbitraire, nummering van snelwegen in Nederland.

De laagste nummers zijn met de klok mee om Amsterdam heen geplaatst en de daaropvolgende nummers zijn geplaatst rond Rotterdam en Den Haag. Vervolgens worden de tientallen over de verschillende provincies verdeeld. Zo zijn de twintigtallen in Zuid-Holland te vinden zijn, de vijftig- en zestigtallen in Brabant en eindigt de rij met de zeventigtallen in Limburg. Geldtekort of achterhaaldheid heeft er voor gezorgd dat niet alle nummers zijn gebruikt, waardoor je bijvoorbeeld tevergeefs zoekt naar de A3 op de wegenkaart.

Ten slotte toonde de natuur zelf de noodzaak aan van een betere kustverdediging. Een verwoestende stormvloed in 1916 zette grote delen van het land onder water met veel schade en doden tot gevolg. Het verkorten van de kustlijn, door het afsluiten van de Zuiderzee, zou de kustverdediging tamelijk vereenvoudigen.

De Zuiderzeewet Bij het aantreden voor zijn derde termijn als minister van Waterstaat weet Lely te bedingen dat er werk gemaakt gaat worden van de Zuiderzeewerken. Zelfs in de troonrede wordt er stil gestaan bij de plannen.

Na oponthoud door de Eerste Wereldoorlog, maar met toegenomen draagvlak, krijgt Lely het voor elkaar om zijn plan in de vorm van de Zuiderzeewet door het parlement te loodsen. Niet veel later starten de eerste werken, maar het zou tot 1932 duren vooraleer sluiting van de Zuiderzee een feit is. De complete inpoldering van wat nu Flevoland is, laat zelfs op zich wachten tot 1968, maar wordt vrijwel exact volgens het plan van Lely uitgevoerd.

Nalatenschap Na zijn derde termijn als minister verlaat Lely de politiek en begint met rondreizen over de wereld om lezingen te geven over de Nederlandse strijd tegen het water. Spijtig genoeg zal hij nooit het resultaat van zijn plan zien: in 1929 overlijdt hij. Tegenwoordig wordt er op de TU/e naar gestreefd om de ingenieur van de toekomst op te leiden die buiten technisch onderlegd te zijn, ook op andere vlakken mee kan. Cornelis Lely is een schoolvoorbeeld van een ingenieur die zijn ingenieursachtergrond combineerde met maatschappelijk engagement. En dat al meer dan een eeuw geleden.

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The world of climbing

An introduction to climbing: different disciplines, basic gear and grading

You may have noticed that over the last few months a new trend has raised among some mechanical engineering students. Climbing has been a topic at the ledentafel, but non-climbers have a difficult time following these discussions. The world of climbing contains a lot of jargon. Also it is unclear to most people what the differences are between the two most popular disciplines, namely bouldering and sport climbing (SC). In this article I will shine some light on these disciplines and also on some basic climbing gear.

Fercan Molenaar

SC: The climber The main difference between sport climbing and bouldering is the difference in height between sport climbing routes and boulders.

A sport climbing route is an imaginary line from the ground to the top of a big rock wall (see the banner picture). The length of routes can differ a lot, but a ‘normal’ sport climbing route can be about 25 meters long. For obvious reasons sport climbers use a rope when climbing routes. Climbers wear a climbing harness and he or she attaches the rope to his harness before climbing, usually with an eight knot. Climbing routes have metal bolts all along the route.

When you climb, you always climb upwards along these anchor points. The climber takes quickdraws with him or her, which are basically two small carabiners attached to each other (see the small picture). During the climb, the climber attaches one end of the quickdraw to a bolt in the wall and the rope through the other end. The small quickdraw picture is a close up of the red oval in the big picture under the title.

SC: The belayer Now let us take a look at the schematic on the right side. The best way to explain how belaying works is to use pictures, so here we go..

Quickdraw and bolt in climbing route

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Simon Ster 49.3 | March 2018

A sport climber always needs a climbing partner: the belayer. The belayer is also wearing a climbing harness with a carabiner attached to it (see picture). This carabiner is attached to a belaying device. The rope goes from the climber down through the quickdraws and then through the belaying device of the belayer.

The belaying device is very important. The rope can slip through the belaying device, but the belayer can determine the friction of the rope with the device. With some devices for example the

Belayer on the ground with belaying device

belayer has to adjust the angle of the rope with the device to control the friction. When the belayer wants the rope not to slip, he or she adjusts the angle of the rope with the device so that the rope cannot slip through. This is called a block. When the climber climbs, the belayer must ‘give the climber rope’ to climb higher. When the climber falls, the belayer blocks the rope so that the rope does not slip through the device during the fall and the climber does not fall all the way down. It is important to note that the climber will fall twice the distance to his last anchor point. In fact, because of the rope stretching it is even more than twice the distance to his last anchor point!

A climber has completed the route when he or she has reached the top of the route, called the anchor. From here the belayer can lower the climber down. The belayer makes sure that the climber is lowered down smoothly. The angle of the rope with the belaying tool is adjusted so that the rope can slip through the device, but with acceptable speed.

are problems that are not overhanging but the opposite. These problems often have tiny features to put your entire bodyweight on, so in this case the climber has to trust that his or her foot will not slip. This can be a big mental obstacle for climbers. On the other hand we have overhanging problems. These typically require some more strength in the biceps and the core. Overhang problems can seem hard for some beginners. When I started bouldering I avoided overhangs and mostly tried to improve my slab climbing. However, overhangs do not need to be as hard as they seem and once you have been climbing for some time, I am sure you will come to like these kind of problems!

Dynamic move to small holds on an overhang boulder

Bouldering

Campus board

A boulder is simply a big rock. The aim of bouldering is to get on top of the rock. Bouldering finds its origin in sport climbing.

Back in the old days, when there were no indoor climbing gyms, climbers used boulders for training: after all the movements are pretty much the same as in sport climbing. Over the years bouldering has become a discipline of its own. Often boulders require climbers to perform hard moves, but the climber has to do way less moves compared to climbing a sport route. In general sport climbing is more endurance based compared to bouldering, which is more power based. Some boulders (and sport routes) are not so much power based, but rather require balance, control and mental strength. I am talking about slab boulder problems: these

These wooden boards are used for training by both sport climbers and boulderers. To campus means climbing without using your feet. The general goal of training on these little rungs is to gain finger strength, since most of the difficult boulders and sport routes have small edges instead of comfortable holds. Let us number the rungs from 1 (bottom rung) to 9 (top rung) and say that L1 means left hand on rung one etc. A common way to train is to ‘ladder up’, so do this: L2 -> R3 -> L4 -> R5 and so on. The distance between these rungs is generally the same for every campus board internationally. Truly world class moves look something like this: L1, R1 -> R5 -> L9. The second move is the hardest, since the mass center of the climber is far below the right hand after the first

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move. The climber now has to pull with the right hand fingers to lift up his or her bodyweight so much that he or she can reach position 9 with the left hand. Of course bodyweight plays a big role here and in climbing in general. The less weight the less strength you need to pull yourself up.

Adam Ondra climbing Silence (9c)

When a climber finishes a sport route or boulder that has never been climbed before, he or she proposes a rating, for example 7a.

The rating can be confirmed by other climber that climb the same project afterwards. Also it is common that the climber who climbs the route/boulder for the first time gives the project a name.

Girl training very hard

Currently the highest proposed grade for a sport route is 9C. The route is ascended only by Czech climber Adam Ondra in September 2017 and he named his project Silence. The hardest suggested grade for a boulder is 9A (note the big difference with 9C!) and it is located in Finland. Finish climber Nalle Hukkataival is the only one to have climbed the boulder, which he did in 2016, and he named it Burden of Dreams. Nalle spent 4 years training for the problem which consists of only 5 hand moves, but that is what it takes.

Grading of boulders and sport climbing routes Internationally there are different systems to indicate the difficulty of boulders and sport climbing routes. The system that I will cover is the system that is used to grade boulders and sport routes in Europe, namely the French system. Boulders and sport routes are graded from 1a up to 9c, the first being the easiest and the latter being the hardest. The letter after the number also depends on how hard the problem is and it can be either a, b or c.

The latter is again the hardest. The letters can also have an extra plus sign, which also depends on the difficulty of the boulder: An 8c+ problem should be significantly harder than an 8c problem.

In bouldering gyms, the letters behind the numbers are generally only used for problems that are at harder than level 5, for example 6a. Problems that are easier than level 2 are rarely found.

Comparing grades for boulder problems and sport routes is not really obvious. A sport route rated 8a is significantly easier than an 8a boulder problem. This is because the moves in the boulder are way harder than the moves in the sport route. However, the amount of moves is way bigger for the sport route compared with the boulder. This is an important concept: the sport climber gets tired during the climb and therefore he or she has more difficulty with hard moves in the beginning of the route than in the end.

Nalle Hukkataival practising moves on Burden of Dreams (9A)

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Design your own 3D-product

Simon Ster 49.3 | March 2018

And the winning design gets printed!

Additive manufacturing technologies have enabled AME to shorten development time bringing optimized products in less time than expected. Having a product within hours has changed the mindset of the engineers, and now we would like to share this astonishing technology with the study association Simon Stevin.

The Printer Stratasys J750 is one of the most innovative machines available in the market. Powered by the PolyJet technology it brings highquality parts with printed layers down to 14 µm and tolerances as high 0.1 mm. The photosensitive material reacts to the UV light and solidifies while printing. The J750 can combine up to 6 different materials, from “default” black, white and transparent, to rubbers and digital ABS.

Materials The Stratasys J750 features a true, full-color capability because it operates with five different colors at once. It can produce parts in over 360,000 colors, textures, gradients, transparencies and durometers. Produce prototypes with an incredible array of characteristics so they look, feel and function like the future products you designed them to be. All of this in a single print operation with minimal to no finishing steps like painting, sanding or assembly.

Want to know more about the J750? Go to the website: www.stratasys.com/3d-printers/j750

The Contest Release your creativity, forget conventional manufacturing processes and design your model from the ground up. Anything can be printed, as long as it can be supported. The J750 can create both static and dynamic models and has the option to coat your model to combine mechanical properties. Your design will be judged on applied knowledge, smart use of materials, creativity, and functionality. Bonus points will be added to kinetic models.

Using designs from the internet will lead to disqualification.

The Stratasys J750

The Guidelines • • • • •

All designs can be sent to 3dprinting@ame.nu, with the text “3D printing contest” in the subject.

Designs have to be sent as a STEP214 or STL-file, combined with the native format (.prt, .sld, etc) Maximum dimensions: 150x150x150mm Maximum volume: 200 cm3 Don’t forget to add your name to the e-mail.

Questions For further information, feel free to contact AME’s 3D Printing Team at 3Dprinting@ame.nu.

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Bachelor Final Project

Optimization in Integrated Digital Image Correlation

In mechanical testing of materials and products, for years strain gages and extensometers have been used to measure strain and stress when force is applied. My final bachelor project however, focuses on a new revolutionary method; integrated digital image correlation.

Bart Verhaegh Introduction

Optimization

Integrated Digital Image Correlation or IDIC is an optical method to do 2D and 3D measurements of displacements in materials by analyzing changes in images. These images are captured in e.g. a tensile test or other experimental setups. The IDIC algorithm registers these displacements by examining a greyscale pattern which has been applied on the product and tries to track the movement of every ‘speckle’ during the test. The image shown above shows such a speckle pattern on a simple tensile test specimen. By examining the greyscale color of every pixel in the image and determining where the pixel should have been in the previous image, the displacements are calculated. Our research group focuses on the usage of IDIC in the identification of material properties or constitutive parameters; by making a simulation of the exact experiment we did in real life and applying the exact same speckle pattern virtually, we can try to align the displacement fields by iteratively changing the material properties. This can be useful when analyzing complex composites or very small laminated materials and specimen. Simulation of the experiment is done using a FEM software solution, such as Marc Mentat.

Perturbating these material properties in FEM and calculating whether the updated model more closely resembles the photographed material can take a lot of time. Imagine trying out thousands of different values for Youngs moduli and Poisson ratios, with the knowledge that each FEM simulation takes a couple of minutes! It then becomes clear that this problem asks for a optimization strategy.

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Simon Ster 49.3 | March 2018

My thesis explores the performance and applicability of different existing optimization theorems on the IDIC optimization problem.

In general, optimization algorithms have the same standardized input: a cost function that takes the vector of dependent variables as input which returns a criterion that is to be minimized, the initial values for the input variables and constraints. In the case of IDIC, the cost function basically is the difference between the greyscale images of the simulation and the photographed images of the specimen. Dependent variables are material properties and possible constraints are e.g. the poisson ratio not exceeding 0.5 or the Young’s modulus being non-negative.

The optimization algorithm’s job is to come up with new values for the input variables based on what the cost function returns.

The algorithm updates the instruction files which define the FEM simulation, automatically runs Marc and imports the results file in MATLAB. Based on the results, the output criterion is calculated.

Basic algorithms that only use the value returned by the cost function are often called random optimization methods; while they do have a certain strategy, they don’t use much information to find the optimum. More sophisticated algorithms use the derivative of the cost function with respect to the input variables.

When updating e.g. five different variables, it can be beneficial to know which of those five variables influences the cost function the most. The partial derivative can be used to determine just that.

Generally, derivative dependent methods needs far less iterations to find a minimum.

The choice between derivative-free or derivative-dependent methods seems quite simple. Unfortunately, a FEM simulation based cost function is of course not analytic and therefore deriving it is impossible. We can however try to estimate it; we take the set of input variables, do the FEM simulation, make a very small change in one of the variables and then simulate again. By comparing their outcome, we have calculated a rough estimation of the derivative with respect to the input variable. So, doing this for all input variables takes N + 1 FEM simulations per iteration, in which N represents the amount of input variables. That’s way more than the single simulation per iteration that random optimization methods require.

Applications Digital image correlation implementations are used widely where solid mechanics expertise is required in industry. For example, Airbus uses DIC to evaluate the structural damage caused by high velocity collisions with birds and small projectiles. DIC enables measuring stress and strain on mechanical components without significant alteration of the structure. Another example of DIC in action is measuring strain on engines in automotive industry; analyzing running engines in real-world conditions requires doing measurements on hot elements in narrow spaces. DIC can operate without touching the engine and is therefore a very applicable

instrument.

Learn more?

If you want to learn more about digital image correlation, the Mechanics of Materials group is doing lots of research on the development and application of DIC. If you are interested in how optimization algorithms work and want to learn how to implement them, the Master course 4DM20 Engineering Optimization explains the maths and principles behind those algorithms and learns you how to use them!

Kleinendorst, S.M. (2014). “On the use of adaptive refinement in isogeometric digital image” Would you also like to tell something about your BFP in the Simon Ster? Please contact redactie@simonstevin.tue.nl

My conclusion was to combine the two methods; random optimization methods tend to be robust and quick, but take a lot of iterations really get accurate, while derivative-dependent methods can sometimes get stuck in local minima which we are not looking for ánd take N + 1 simulations per iteration. Using the derivative free methods to estimate the solution and then switching to the more sophisticated methods to increase accuracy, provides a trade-off between speed, accuracy and robustness. This solution has been implemented in the algorithm using the MATLAB Optimization Toolbox, which supports a large set of algorithms.

The updated IDIC code enables researchers and engineers to analyse complex materials more effectively.

Pattern search method by Andrea Cirillo

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Land yachting in the desert

The great trans-Sahara sand yacht race

Sand yachts are normally found on the beach right? Normally they are, but in 1967 twelve sand yachts took on the huge challenge of driving 3000 kilometers through the Sahara Desert.

Kevin Looman A French colonel, Jean du Boucher, had spent fourteen years in West-Africa and had dreamed about crossing the Sahara with sand yachts for a very long time. In 1965 he therefore made an exploratory foray of 750 kilometers in a sand yacht to find out if a race through the desert was feasible. Encouraged by the result, he decided to organize the first sand yacht race through the desert ever. The route he chose was an historic caravan route on which the wind was expected to blow for 26 days per month in the right direction. Based on this information and assuming the sand yachts would sail eight to ten hours per day, the colonel calculated the sand yachts could cover the 3000 kilometers in one month. Sand yachting clubs worldwide received an invitation and seven British, three American, three German, three Dutch, one Norwegian and five French pilots responded. The French entry included the European champion and the only female contester who was also the European lady champion. As you might have noticed, more pilots participated than the twelve sand yachts could seat. This was planned as the pilots would share the yachts provided by the colonel.

Preparations Twelve sand yachts, six land rovers, a couple of army trucks and two reconnaissance aircrafts were necessary to race the Sahara desert. The colonel, due to his experience in the desert, insisted that each yacht should carry compasses, maps, a signaling mirror, a walkie talkie, distress rockets, smoke signals, a UHF radio, a first aid kit, a tow rope, tools, spare parts, camping gear, food and water for four days and survival rations for eight days. To store this, every piece of empty space on the sand yachts was turned into storage space. The British team was not able to pay the ÂŁ155 per person due to foreign currency restrictions and agreed to provide three of the sand yachts and four Land rovers.

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Simon Ster 49.3 | March 2018

Start

Race concept abandoned

On the twelfth of February 1967, the sight of twelve sand yachts amazed the Algerian crowd at the start. A steady fire of comment and prophesies of a slow death by the desert sun from the crowd is launched upon the pilots. The spirit of the pilots was unaffected tough, since the crowd spoke mostly in an Arabic dialect. The planned starting time arrived, but the wind was nowhere to find.

Unfortunately, the complete first day went by without a gust of wind and the only distance travelled was the 5 kilometers tow behind the Land Rovers to escape the crowd. The next morning the wind awoke, the inglorious start took place and the sand yachts started sailing the asphalt road they would follow the first 530 kilometers.

A serious problem became apparent during the first days of racing. When the road curved and headed into the wind the pilots would push their yachts with all the energy they had, despite the intense desert heat. This caused a serious risk of pilots getting exhausted in the middle of a desert. While waiting for the rocket launch the organizing committee, consisting solely of the Colonel, was criticized by the pilots and decided to drop the race concept.

From now on the yachts would sail in convoy and points would be awarded for reliability.

Rocket Launch On the second day disaster struck for the British team. One of their yachts hit an electric wire without current. The levering operation of the long mast broke the yacht in half. Two British pilots transported the yacht 320 kilometers to the nearest shop with good tools, where they rebuilt their yacht in time to rejoin the race three days later. The others made good progress in light winds until they were stopped by the French army. Lead by the retired French Colonel, they demanded passage, but the soldiers declined them, telling that they were driving into “Rocket range”. So a camp was set up and the next day they witnessed the launch of the last French Diamond 3 satellite and visited the tracking station. The two days after that were spend crossing the Hamada du Guir, a desert covered with rocks and interspersed with gulley’s. Nearing the end of the plateau, the pilots were greeted by local Meharstes riding their camels, with a traditional “battle”. In this “battle” the goal was to encircle each other. The pilots accepted the challenge and after two hours the yachts had won, but the enthusiasm, combined with the rough terrain, had damaged the wheel mountings of three sand yachts beyond repair.

Sailing to Tindouf About 200 kilometers before Tindouf the terrain changed. The yachts have to maneuver over hard flat gravel with lots of acacia trees that have sharp thorns, terrain the French team had not expected. Their yachts were fitted with thin walled tires and long before the finish the colonel had recorded 500 Flat tires, after which he stopped counting. Other yachts were suffering from axle breakage because of the rocky surface, but fortunately had enough spares. Apart from the breakdowns good progress was made. Nearing Tindourf the pilots were accompanied by camels that raced besides them. The people of the town had gone to great lengths to welcome the party, building arches over the streets and displaying flags of all countries represented. The Pilots however ignored all these preparations and sailed straight to the legendary hot baths of Tindourf.

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Sailing the “real” desert After a resting day in Tindourf the route became a lot harsher. 885 kilometers of desert lied ahead, without water and without a trail to follow. The colonel recruited eight extra guides to guide the yachts through this wilderness and they are ready to depart. The terrain remained rough and flat tires were abundantly present.

Morale had been down since the competition had been reduced from a race to a battle of reliability. The pilots were living on a diet of thinned beef with rice, digging out the jeeps multiple times a day and fixing about twenty flat tires a day. Two pilots then had to push their yacht 25 kilometers through the desert after being completely ignored by the support vehicles. After this push one of them again criticized the colonel for the way the race was organized, in response he told him “if you don’t like the way this rally is being run, you can take the next plane home”. This is exactly what the French pilot did.

When a sand storm blew up the Colonel was faced with an awkward decision, the water supply had nearly run out. The pilots therefore had to push on to make it to the water hole. Reefed sails do the trick and they are able to find the water hole. Morale is sinking even lower when instead of finding water, they find mud in which camel dung floats. The Colonel advises the pilots to let the water settle before drinking and fills up the jerry cans.

Finish On the 15th of march, 31 days after departure, the pilots were received by cheering crowds and the president of the State at a grand welcoming ceremony. In 31 days they had sailed more than 3000 kilometers through the roughest terrain in the world. The pilots achieved something everyone thought was impossible and received the gold medal of the National Order of Mauritania. The race turned out to be less of an race and more of an adventure.

Because the race format was dropped, and later on also the point system for reliability was dropped (no one had a truly reliable sand yacht), no one was the “winner”. But it was an amazing adventure and a show of what people can achieve if they are convinced something is possible.

Heading towards known territory Less than 350 kilometers to the sea only eight yachts are left and the pilots are joking about the thought of bathing in the ocean.

The joking stops when the wind dies, leaving them motionless in the blazing sun. The Colonel decides to tow the Yachts, to at least create their own wind. Riding to the top of every hill the pilots think they can see the ocean. However every white line they see in the distance turns out to be a mirage. When they finally reach the ocean, everyone runs into the sea except for the local guide who had never seen so much water. The last 100 kilomters would be sailed on the beach. The beach however was at some places filled with rocks and the pilots were forced to drive with one wheel in the ocean, the other within the water line.

This article was written based on an article in the National geographic society 1967, Volume 132 No.5 written by the Colonel himself, which describes the race as a great success. And a report written by the British team in which the colonel’s organizing and decisions are greatly doubted. Hopefully the combination of both yields an good representation of the events.

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Taekwondo

Simon Ster 49,3 | March 2018

A short history

General Choi Hong Hi was born on November 9th, 1918 in the Hwa Dae, Myong Chung District. This was back in the days when North- and South-Korea were still united as one country, occupied by the Japanese. Choi Hong Hi is the Founder of Taekwon-do and the first president of the International Taekwon-do Federation (I.T.F.).

Ken Dekkers Choi integrated a few martial arts to form Taekwon-do as it is today, mainly Taekkyon, karate and kung fu. At a young age, his tutor, Master Han Il Dong, taught him Taekkyon: the ancient Korean art of foot fighting. He travelled to Japan and studied English and mathematics. A fellow Korean was a karate instructor and taught Choi karate. Furthermore, Choi learned Shotokan karate under Funakoshi Gichin.

In 1937 Choi was forced, like all Korean soldiers, to join the Japanese army. In 1942 he returned to Korea and hid, to avoid conscription into the Japanese Army. Nevertheless Choi was caught and started in the army in 1943. Soon he got arrested for attempting to join the underground Korean Liberation Army. On August 18, 1945 he should have been executed, if it was not for the liberation of Korea three days before his due date.

General Choi Hong Hi

In the same year he joined the Koreans Military Academy. The years following he promoted to Lieutenant Colonel and was a Taekkyon instructor for military troops. Choi got promotions hereafter and eventually promoted to Major General in 1954. During his military career, General Choi studied and trained many martial arts, mainly Taekkyon, kung fu and karate. These martial arts formed the base of his new martial art: Taekwon-do.

To promote his new martial art as a form of unarmed combat, Choi led a Taekwon-do demonstration team throughout China and Vietnam. The result was positive as both countries integrated Taekwon-do in their military trainings program and the Korean Taekwon-do Association was formed in 1961. The South Korean government approved the new martial art as Korea’s National martial art. General Choi did many tours throughout the world to further promote Taekwon-do as a new martial art. General Choi Hong Hi founded the International Taekwon-do Federation in 1966 in South-Korea. Already a lot of countries were associated and Taekwon-do was taught in different military training programs around the world.

In 1971, Taekwon-do was used in South Korea as anti-communist political propaganda by president Park Chung Hee. General Choi strongly disagreed, but had to go into exile in Canada. He still did teach Taekwon-do in North Korea, where he was still welcome. 15 June 2002 General Choi Hong Hi died of cancer and was buried in Pyongyang, North Korea.

Choi Hong Hi made I.T.F. Taekwon-do what it is today. Taekwon-do has evolved in all the years since its origin, with members all over the world. Taekwondo consists of different aspects, patterns, sparring and hosinsul. Patterns are an important aspect in Taekwon-do; it is comparable to a kata in karate. The name actually explains it, performing a pattern with different techniques of Taekwon-do to an imaginary opponent. Sparring is comparable to sparring in kickboxing. Taekwon-do differs from kickboxing, because in competition the goal is to score the most points and not to knock out the opponent. Hosinsul is the most practical part of Taekwondo. Imagine you are in combat out in the streets where there are no rules. In hosinsul, Taekwon-do techniques are used, combined with self-defense techniques against for example headlocks and armed attacks. Two more aspects are practiced in Taekwon-do competition besides the three aspects mentioned above. During special techniques, competitors have to perform various jumping kicks at targets at a height of about 2.5 meters high. The other aspect consists of breaking as much wooden boards in a row with one single technique.

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A new Wafer Feeder

Top performance in the field of mechatronics and motion control

R&D manager Robbert van Leijsen of Kulicke & Soffa (K&S) and manager projects Jarno Lathouwers of Sioux leave no room for doubt. The development of K&S’ new wafer feeder was no sinecure. It required constant interplay of their best people: commitment and engineering at the highest level. ‘Masterpieces of this type are only possible if you operate as one team.’

K&S Eindhoven - formerly known as Assembléon - and Sioux are no strangers to each other. Sioux has been called in by the OEM in pick and place machines regularly since 2006, for example as a development partner in software, electronics, remote connectivity, vision and mathware. Over the last two years, the relationship has intensified during the development and construction of a state of the art wafer feeder.

Where the semicon industry is driven by miniaturisation of integrated electronic circuits, smaller components must also be applied to PCBs. That calls for new requirements for surface mount technology, K&S’ domain. In addition, classic wire bonding increasingly makes room for new advanced packaging technologies to connect and stack at die-level.

Fastest in the world ‘The advanced packaging pick and place battle is fought from two sides,’ according to Van Leijsen. ‘High-precision machines are becoming faster and fast machines are becoming increasingly accurate. Assembléon originated from the latter and proves very successful in this. K&S took us over in 2014, and rightly so. It gave

us a boost on a number of fronts. This included the development of a new wafer feeder, almost a pick and place module placed for a pick and place machine. Wafers are inserted, fed through and stretched. Then a die is raised from the wafer. It will be caught by a suction cup and handed to the pick and place robot. After passing a flux dipping station and vision module, the die will be placed. All in all, we have created one of the smallest horizontal wafer feeders in the world. It can compete with the fastest machines and pick up dies up to 0.5 by 0.5 millimeters.’

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Simon Ster 49.3 | March 2018

Competences and culture At the start of the development process, one thing was clear to K&S: collaboration with a technology partner was essential. You simply cannot claim your entire engineering organisation for a new project. The company almost immediately thought of Sioux, because of the clear match in competences and culture. The concept development took place at K&S and took three months.

For the design phase and prototype building, the joint team was moved to Sioux and was scaled up to twenty people for several months. After the prototype, the 0-series has also been developed and built.

Lathouwers: ‘The joint team performed at top level in the field of mechatronics. We assembled our best people because of the complexity of the project. First of all, there was a very challenging and inescapable restriction: the available space. Next to this, there were strict requirements in terms of speed, accuracy, robustness, product cost and development time. With so many variables, the trade-offs are almost infinite and you may start to run in circles.

So, apart from having to make keen choices from the first concepts onwards, you must also work with simultaneous solutions. This requires craftsmanship and a strong capacity for abstraction at system and detail level.’

World-class performance Thanks to parallel software integration and testing, K&S’ new wafer feeder is ready for the market. This has resulted in a worldclass performance, also from a time to market perspective.

‘These masterpieces can only be created if you operate as one team. It involves more than just picking up a huge challenge and commiting to it, which is usually not a problem if you have some technicians join a team. Creating the optimal architecture and detailing it further in the engineering is a constant process of resolving technical conflicts. To do that optimally, everyone must think the same way. You can see this at K&S and Sioux. Our engineers use uniform methods and standards, and transfer their knowledge and experience to the new generation and each other.

We speak the same language and show the same behavior. That pays off on the work floor, when people - often without making a fuss - take very practical decisions that connect seamlessly.’

We bring high-tech to life Working at Sioux, means working together with a team of driven, smart and fun colleagues on high-tech solutions that make a difference. As a talent in mechanics, mechatronics, software, mathematics, automotive or electronics, you will contribute to the development and construction of complex products, often on the verge of what is technologically possible. In most cases, you will work from one of our own Development Centres.

Working together for the best results The best results are achieved by teams that work together optimally. That is why you work with smart and motivated colleagues, who are committed to find exceptional solutions together. In some projects you will be able to focus on your specialism, in others you can be involved in all phases of the development process.

Working on your development Our employees are our strength. Based on that belief, we find it very important to guide you optimally in your development. At Sioux we will keep you focused; we will constantly challenge you to learn and take the next steps in your development. Therefore, we work with a generous personal development budget which allows you to keep your technological knowledge up-to-date and work on your personal skills. Your current competencies and ambitions will determine the direction of your future career path and the level achieved.

Check out our jobs, internships and graduation assignments on: jobs.sioux.eu

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Windsurfing

Explained by WETH

One of several sports I tried while going through puberty is windsurfing. Because wave surfing looked cool, but also exhausting… By putting a sail on top of the board, you take out the exhausting part and keep the cool part, brilliant!

Niels van de Straat, president of E.S.W.V. WETH Since my dad had an old windsurf set lying around, it was time to get started. In a lot of aspects windsurfing is similar to sailing.

The major difference is that: you go faster, you are more agile and you get more WETH. Windsurfing is either inherited, or people try it during a holiday. The main problem with windsurfing is that it takes a lot of effort to learn. So if it is only tried once during a holiday, you won’t be able to do much. To keep members engaged in the sport we use encouraging remarks, like: “Planing can be learned”, “Hooking in is participating” and “Dick in the sail”! Which all work a lot better in Dutch than they do in English.

Before I explain planing, we first have to cover the basics. So, how does a surfboard actually work? To keep it simple, the wind applies a force to the sail, the surfer counters this force by using its weight and the fin changes the direction of movement from with the wind to across the wind. As can be seen in the graph, the maximum force applied to the sail is limited by the mass of the surfer. Damn you, Newton!

Now that the basics are known, the speed can be increased, until planing is achieved. Planing can be explained as skimming over the water instead of cutting through it, like a duck landing on water. Archimedes’ principle states:

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Simon Ster 49.3 | March 2018

“Any object, wholly or partially immersed in a stationary fluid, is buoyed up by a force equal to the weight of the fluid displaced by the object.” (Wikipedia, 2018) At low speeds the weight of the surfer and the gear press on the water, lowering it slightly into it according to the buoyancy of the board. The fin creates lift like the wing of an airplane. The lift increases with an increase in speed, hereby decreasing the water that is displaced. At a certain point the board is lifted out of the water completely and starts planing. When planing is achieved, the drag decreases dramatically, allowing higher speeds.

Olympic games. Everyone has the same gear and the surfer that finishes the course first wins. Wave surfing can be seen in the Red Bull Storm Chase. This match is made for the craziest people on earth: They wait for a massive storm to hit the world and then they go windsurfing. 8 meter high waves and 100 km/h winds make it almost impossible to hold on to your gear. Sails are torn, boards are broken and the participants are kept from drowning by life guards on jet skis.

The current windsurf speeds record is at 98 km/h. This may not seem like much on a highway. But try it on a gravel road, which is similar to doing it on a bumpy surface like water. I can guarantee that it feels fast.

When surfing at high speeds becomes boring, it is time to show the wave surfers that there are more efficient ways to do wave surfing. When we want to have some fun in the waves, we need to change a few things. We need to be even more agile, unless you want to be slapped around like a ragdoll by the pounding waves, the board, the fin and the sail need to be smaller. After surfing on flat water with a big board, it becomes clear that surfing at sea is a league of its own. The smaller gear makes you more agile, but also a lot less stable. The smaller fin creates less lift, so we also need a dash of speed. Since the sail is smaller, more wind is required for these sessions. More wind usually results in high gusts, increasing the difficulty even more, what’s not to like?

After accidentally jumping from time to time, it turns from scary into fun and you start doing it on purpose. Time to challenge Newton once more, this time in the vertical direction! Using the high speed of planing and a nice wave as a ramp, the sky is the limit. Or your ankles, because the landing can be quite rough. Luckily you don’t need a lot of height if your front flip is fast enough.

If you want to challenge yourself even more, there are windsurfing competitions. There are several disciplines; RS-X, Formula, Slalom, Speed, Wave and Freestyle. The first four are different type of racing and at the last two you get awarded points by a jury for the tricks that are shown. There are several matches that are well worth watching; the RS-X can even be seen in the

Drowning is not the only risk, because we also have hypothermia.

Windsurfers use a suit to keep them warm. There are two choices; a wetsuit (shorty/steamer) or a drysuit. Drysuits are mostly used by divers, because they are in the water at all times. The suits keep you completely dry, so no matter the temperature you can put some proper clothing underneath the suit to keep you warm.

Wetsuits are commonly used by windsurfers, because they are not in the water all the time. It works like this: the suit allows a small amount of water to pass through the neoprene but keeps it between your suit and your body. Your body heats up the water inside the suit and the water maintains its temperature because of the insulating property of the neoprene. During the summer months, a full wetsuit (steamer) retains too much heat, but it’s too cold to go in your swimming shorts. A shorty is the solution, this is like having shorts and a t-shirt on, only they are made out of neoprene. This way, windsurfers are capable of going surfing the year round.

Neoprene fabric

Curious? We have a student surfing association here in Eindhoven! With E.S.W.V. WETH you can do Windsurfing, Kitesurfing, Wakeboarding, BBQs and drinking beer! The windsurf lessons are free during our surfing weekends, feel free to join us!

40

Ice-Skating

An introduction to an ancient sport

Ice-skating, a secular activity where almost everybody has grown up with. Back in the days, when the crates of beer were still made out of wood and you had to booze to keep the heater warm, the lakes, ditches and streams of the Netherlands were often frozen solid. Everybody massively took their ice skates from the grease to restrain the ice. The ‘Koek en Zopie’ (catering) was counting its profit and the idyllic picture was complete.

Stijn Middelhuis However, ice skating nowadays is not the same anymore as it was before. Where Ard Schenk, a famous Dutch ice skater from the 60’s/70’s, was the first man who achieved to skate the 1500 meters in less than 2 minutes. This world record is already sharpened with a time of 1.41,02.

Skating has incredibly improved over the years where each time the limits are pushed even further.

It is impossible to recover where and when the ice skate has been invented. Nobody knows exactly who was the first to experience the ‘Eureka moment’ when he or she mounted metal pieces underneath his or her feet for the first time. It can be stated from archaeological finds that human beings from the prehistory already looked for better ways to be able to cross the ice faster.

The skates were crafted from bones of animals and shaved until the surface area was smooth enough. Because of that, the very first skates are called ‘glissers’; a glis was the name of a rib or

metatarsus from a horse, deer or ox. The glissers were provided with holes and one could tight them underneath the foot with the use of tendons or eel sheets.

Wood for Bones There are illustrations present, originating from the middle ages, which clearly show that people used some sort of metal or bones to move on the ice. The bones were still used for centuries in Friesland, while the metal skates were already invented in other parts of the Netherlands. These bones were eventually replaced by a metal skate, which was attached to a construction made out of wood. This type of skate was called the ‘Friese doorloper’, also known as the ‘houtjes’. They were attached to the foot and tightened with rope or ribbon. A typical characteristic of the Friese doorloper is that the metal skate completely covers the heel. Many wooden skates of that time only covered half of the heel.

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Simon Ster 49.3 | March 2018

Speedskating Speed skates are relatively old, way older than most people think. Mainly Friesland has been a very important player in the development of the speed skate. The many frozen ditches and lakes of this region were very inviting for ice skating, and many times it was also a necessity to cross long distances across lakes.

When a physical effort is needed to increase speed, the desire of competition arises automatically. This new way of skating asked for a new type of skate. The skates became shorter and stronger, which could be used for competitions for short distances. Because the tracks became longer, the skates evolved even further. The skates were made longer and thinner, but were still made out of wood and metal.

The speed skate as we know it today was found by the Norwegian Axel Paulsen, who was the first to mount metal skates underneath his boots. The name of the skate refers to the nationality of this man, Norwegian. Or how we call it in Dutch: Noor. Not very long after this Harald Hagen used a metal tube to clamp the blade.

This construction was incredibly stiff for that time and it became possible to use even thinner blades. The new ‘noren’ or speed skates completely changed the world of skating and can be seen as the most important development ice skating has experienced.

The traditional wooden Dutch skates disappeared of the ice and the steel ‘noren’ took over the monopoly. They are nowadays still the number 1 skates.

Loved and notorious: The clap skate Although the clap skate was already invented in 1984, the invention was not commercially used until 1996. In collaboration with the faculty for human movement sciences of the Vrije Universiteit Amsterdam, Gerrit Jan van Ingen Schenau created the clap skate. The blade of the clap skate is attached at only the tip of the shoe. This attachment consists of a joint, loaded with a spring which enables the blade to rebound. This way, the blade can stay in contact with the ice for a longer period of time. A longer contact with the ice leads to a longer force distribution, which results in an increase of speed.

Of course, a clapping piece of stainless steel which is attached to a spring sets the heart of every self-respecting mechanical engineer on fire. After all, the clap skate can be seen as a very nice mass-spring-damper system. However, when the clap skate was introduced, not everybody was as enthusiastic as we are.

The responses were more or less giggly. Most skaters of that time stayed with their familiar and reliable skates and did not want to switch to that new fancy stuff. But when Tonny de Jong achieved

some overwhelming successes with the clap skate, everybody became speechless, the giggly ambiance made place for interest and jealousy. The correlation between the success and the “new” skate could not be denied anymore. It did not take long before the top of the speed skating world was using the clap skate. Nowadays, the clap skate is the new standard for both professional and recreational skaters.

And now?

Does the introduction of the clap skate means that the development comes to a stop? If it is up to some fanatics not.

In the past couple of years, some new skate types have been developed with more or less success. An example is the heat skate.

Because a blade gets a lower sliding resistance when it is heated, an electric element which heats up the blade is added to the skate.

This provided the skaters indeed with a benefit, but it was not accepted for competition. For this reason, the development of this new type of skate was stopped.

Another example is the 3D skate. The clap mechanism of this skate can rebound in two directions instead of one. This type of skate could increase the time of contact with the ice even further, since it does not only clap 10 degrees up, but also 14 degrees inside.

Despite the fact that nobody was very enthusiastic about these skates for competitions, ice skate manufacturer Raps did put it on the market. Jan Maarten Heideman was interested in this idea and won the ‘alternatieve Elfstedentocht’ on the Weissensee and dominated the national marathon competition for two seasons on these skates. Maybe the same effect as with the normal clap skates will take place for this invention and the 3D skate will have its comeback.

A very new idea which is still in development is the duoskate. The blade of this skate splits in two pieces when the skate is clapped.

The back of the blade is fixed to the shoe, while the front part of the blade claps open. The potential benefit of this skate is that it can provide more stability. This skate is further developed by Raps and some marathon skaters are testing the concept.

While the development of the ice skate continues, it seems to me that there is not much to improve on anymore. The best changes of gaining time is in my opinion in the development of the speed suits. The air resistance is after all significantly greater than the sliding resistance of ice. But in the end it always stays a surprise; who knows what crazy new idea can shock the world of ice skating again and can become the new standard.

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Sterrenhoekjes Geniet mee van deze volkomen uit hun verband gerukte uitspraken, verpraatsels en vertypsels. Mocht je er nog meer horen: aarzel niet en stuur de uitspraak en context op naar sterrenhoek@simonstevin.tue.nl! Mocht deze onzin je erg bevallen, dan kun je ook via de website non-stop up to date blijven met de sterrenhoekjes via Sterrenhoek live!

Chloé komt binnen met 1 schoen: ‘Ja sorry mijn voet sliep dus ben m onderweg verloren...’

Sifra tijdens een ALV: ‘Wat is een A.P.P.?’ Lex: ‘Dat is een app’

Bart: ‘Wat is een Frituurvogel?’

Sjors tijdens het kijken van curling: ‘Als vrouwen willen poetsen moet je ze gewoon laten poetsen, dat kun je niet onderdrukken.’

Steen na een tiki taki: ‘Ik weet even niet wat ik nu moet voelen’

Dirkje: ´Verknallen is ook knallen!´

Robbert: ‘Alle vrouwen zijn dictators, maar niet alle dictators zijn vrouwen.’

Olaf: ´Wie verzorgt hier de thee? Die moeten ze echt vierendelen!´

Moeder van Sem: ‘Die kale jongen hè, is die eigenlijk al klaar?’

Contest As always we have a new contest for the reader who likes a challenge. This time, the winner gets a brand new airfryer. The model can be seen below and for anyone who isn’t familiar with the current airfryermarket; it is the Philips Airfryer HD9621/40 Viva.

If even this doesn’t ring a bell, I can assure you it is a very decent airfryer and it happens to be exactly the one you need.

Contest 49.3 So we have yet another problem. The Commissioner of Education went to Stratumseind on a regular Thursday but when he arrived at the Simonkamer the next morning, he found an odd paper in his jacket, which you can see below. Unfortunately, he couldn’t remember how or where he got it from, but he still knew it had a solution. According to him, the empty space in the square should be filled with the right symbol. Do you know what the symbol looks like?

Answer 49.1 In the last Simon Ster we had the following contest, where the Chairman was looking for a certain number: The Chairman is looking for a number, but not just any number of course. What he needs is a number, which, when squared, contains all digits from zero to nine. The number I am looking remains the same when you look at it upside down in in your digital calculator.

Solution As always, the Editor-in-Chief received a lot of MATLAB scripts which he could run himself to find the solution. Luckily, all smart solvers of the puzzle also provided one or more answers already, so he didn’t need to find them himself. There were an infinite amount of possibilities, since you can make the right number larger and larger if you want. However, there is one elegant number which contains all numbers from zero to nine only once, which is: 99066*99066 = 9814072356 If you are interested in the all the other solutions, you will have to write a MATLAB script yourself!

Submit your answer in the Simonkamer (Gem-N 1.61) or send an e-mail to redactie@simonstevin.tue.nl with your name and the solution. The prize will be raffled from the correct submissions and we’ll publish the winner in the next Simon Ster.

Make sure to send in your answer before the 30th of April!

Out of the submissions only one can win and the go home with the decent Dutch Oven Pan . The winner of this beautiful piece of kitchen equipment is Bas Straatman! He can pick up his prize in the Simonkamer.

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activities w.s.v. simon stevin march

april

easter 1. company visit: vmi group easter 2.

3. Land yachting weekend 4. Land yachting weekend 5. bouldering 6. wervingsdagen: Career expo 7. wervingsdagen: Career expo 8.

Exams 9.

Exams 10.robowars Exams 11. robowars Exams 12. accie + reaccie drink Exams Exam 13. gmm 61.5 Exams 14.lunch lecture: van oord 15. st. patrick’s drink Exams 16.

Exams 17.

Exams 18.

Exams / live music drink 19.company visit: fokker Exams 20.beer bee tasting Exams / Batavierenrace Exam 21. lunch lecture: engie / w-hoog party batavierenrace 22.Charity drink: Kidney foundation hannover messe visit 23.information days tu/e gmm 61.6 24.information days tu/e lunch lecture: tatasteel / myfuture day 25.

26. kingsday 27.Reaccie: beergames 28.symposium automotive 29.dies di drink de weeghconst / sinas 30.heft 31.

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