Engineering portfolio - January 2019

Olek Warchalowski Portfolio

First of all, I want to be part of a great team – like on the photo above: my Formula Student team prepares the car to dynamic events at FSUK, next to Force India’s HQ at Silverstone.

Secondly, I am an individual: on the photo, you cannot easily tell who stands where. Also, neither of the silhouettes looks the same. Yet all of these people contributed to building one of the fastest cars on track, and we would not get there on our own. I am presenting this portfolio to you, to showcase projects I have been involved in the past. Perhaps they build a potential to work with you in the future.

OBR18 – Formula Student

Aerodynamic Package design Objective

To develop Aero package for Formula Student • Compliant with FSG2018 rules • 10% Downforce increase • Reduction in manufacturing tolerances • 2kg weight reduction • Validate properties of Front Wing’s main and footplate vortices.

Scope of work

• Surface CAD design of Front Wing and Underbody components • CFD analysis of new part’s performance • Mechanical design for Front Wing, Underbody and Rear Wing components • Test programme including pressure distribution measurement (track)

Results

15% downforce increase Weight target met Improved package quality, delivered on time Package validated during full scale wind tunnel test – results within 10% error • Successfully implemented on surface pressure scanning • • • •

Bottom line

This has been the most challenging project I have undertaken so far. I took an entire package of parts from feasibility study (what can / should be improved given the resources?) to concept design (how can the improvements be made?) to surface and mechanical design and validation (have the goals been achieved, what is further work?). I have thoroughly enjoyed the whole process and would love to be involved in equally broad projects in my future career.

OBR18 – Formula Student

Implementation of 3D printed tooling for carbon pre-pregs

Objective

Find suitable tooling for carbon pre-preg parts • Thermally stable up to 120*C • Stiff – max 1mm deflection in a vacuum bag • Non porous • Smooth and durable surface finish • Fast manufacturing, freedom of shape • Lower cost than tooling block manufacture

Scope of work

• Liaising with 3D printing sponsor to establish most suitable material and technology for requirements above • Concept, CAD model and technical documentation for 8 bespoke moulds • FEA analysis, iterating design to minimise deflection • Delivering technical report for the sponsor with results of implementation

Results

• Tooling for intricate geometries of car’s front wing with SomosPERFORM • Moulds suitable for out of autoclave pre preg processing • 25% lower cost compared to tooling block – cost subsidised by the sponsor in exchange for testing carried out

Bottom line

I thoroughly enjoyed this project as it’s given me exposure to state of art SLA printing materials and unique application of those. I was able to deliver design, learn about potential design limitations implied by thickness of the part and surface quality, carry out empirical testing and find optimal curing cycle. I also had to be creative with the mould design to minimise cost – thanks to 3d printing it was possible to utilise fraction of material volume compared to tooling block, which made this solution also more sustainable.

OBR18 – Formula Student

Aerodynamic Package design • • •

Team classified on 2nd place overall at Formula Student UK and 2nd place in the Design Event, where I was part of 5 person team presenting the design of the car.

Team awarded with a sponsored wind tunnel test day Car featured in 3 consecutive issues of Racer Engineering magazine

OBR18 – Formula Student Front Wing Mount design Objective

• Weight of single mount to not exceed 350g • Must support 450mm chord wing placed entirely in front of the chassis.

• Provide adjustability of wing attitude

Scope of work

• Kinematic design of the mount for adjustment of ride height and angle of attack of the wing • FEA analysis of the assembly • Technical drawings for all sub components • Hand calculations including shear stress on fasteners, required bond area • GD&T on locating features of sub components

Results (as of 01/2018)

• Front Wing Mount allowing +/-20mm attitude and +/- 6° angle of attack • Estimated mass approximately 335g • FoS 1.35 – possible further mass savings after validating system Top: New design reduces wake coming of FW mount (circled on left). Bottom: FEA plot and CAD render.

Bottom line

Complete re-design of structurally critical component of Front Wing package required very thorough approach. I evaluated functional (what range of adjustments is missing on current solution), performance (how does geometry affect aero), structural (what loads will be exerted) and legal (bounding boxes defined in rules) requirements for the part and came up with a concept, which was then optimised for minimum mass and deflection via FEA.

OBR18 – Formula Student

Operations Engineering Objective

To improve workflow within Formula Student team by improving existing processes, implementing new tools for documenting the design and preaching best practices.

Scope of work

Top Left: Excerpt of Gannt Chart for delivering aero design Top Right: Excerpt of timetable for interviews organised for MSc students Bottom Left: Brief written for aero designers Bottom Right: Key for logging design documents into new database

• Restructure timeframe of aerodynamic package development at OBR to increase design phase from 6 to 11 months • Implement new system of recording design documentation • Invent and execute new system of recruitment of new team members • Implement Product Data Management software • Acquire access to novel materials such as CFRP preforms and Laser Sintered Carbon

Results (as of 01/2018)

• 80% of OBR18 Aero package designed; OBR19 to be designed between Feb-Dec 2018.

• Record 20 MSc students involved in the project (40% increase over previous year) • Currently evaluating 2 PDM systems for Solidworks

Bottom line

Having researched top FS teams I found that their core is made of senior students working on FS as part of their degree for entire year – hence my efforts to involve more Masters students and increase design time. While working at Triumph I learned advantages of using PDM software and I plan to implement it in OBR to improve knowledge transfer and traceability of documents. Finally, using my University’s presence in the industry I acquired access to new materials: designing and handling them will increase my skills of a design engineer.

Oxford Brookes University Active Stability Control System for a road car Objective

• To develop a driver and car model capable of following handling manoeuvres • To develop active stability control system to improve handling of the car

Scope of work

• Set up a model of car, driver and tyre (nonlinear) in MS ADAMS • Determine parameters that limit performance of the car during the manoeuvre • Develop an algorithm to: • Recognize oversteer and understeer • Apply braking to individual wheels to regain control • Counter-steer

Overlay of two cars negotiating ISO3888 lance change – orange car has stability control algorithm switched off, green car has stability control on

Results

• Created working virtual model of a car that performs ISO3888 lane-change • Maximum entry speed with the stability control “on” increased by 20%

Bottom line

Comparison of slip angles and steering input for car with stability control “off” (left) and “on” (right). Notice sudden peak in rear slip angles when car spins out of the corner

This project was part of group coursework at Universtiy. The whole timeframe of the project was limited to 10 weeks, which included 7 weeks for learning new software (MS Adams). I enjoyed this project a lot, as I haven’t been taught vehicle dynamics before and thanks to the guidance of our lecturer I managed to quickly digest solid amount of theory and immediately apply it to my first active control system. I am looking forward to broadening my knowledge in this area in the future throughout either professional work or individual studies.

Triumph Motorcycles Side Stand design for a production motorcycle Objective

• Re-design side stand for motorcycles due in volume production in 7 months • No yield at 8kN load • Improve ergonomics of the part

Cradle-sidestand clearance

Scope of work

Results

• Passed SAE homologation (stability) • Passed physical overload testes • Currently part of three production bikes!

Bottom line

14 Sidestand – frame clearance (mm)

• Calculate effect of manufacturing tolerances across ~30 components on clearance between side stand and frame • Produce surface CAD model of the side stand • Design GD&T to allow implementation of new clevis design and ensure the best load paths are maintained at all tolerance conditions • Evaluate stress on the side stand spring and improve fatigue life

12 10 8 6 4 2 0 0

50

100

150

200

Distance from sidestand pivot pin (mm)-> OLD SIDESTAND CLEARANCE

NEW SIDESTAND CALC CLEARANCE

Looking after side stands became one of the main projects during my Industrial Placement at Triumph. Due to timing of bike release, I often worked under pressure of short deadlines (i.e. drawing for forging was issued to supplier 9 days after discovering requirements for change). Apart from delivering technical documentation for this part I also liaised closely with suppliers from far east which greatly improved my understanding of automotive industry, importance of clear communication and product liability.

Triumph Motorcycles Seat Latch routing design Objective

• Design a feature retaining seat latch cable • Ensure appropriate ergonomics, aesthetics and minimise cost of the solution

Scope of work

• Calculate tolerance stack across seat latch assembly • Evaluate ergonomically best placement for the seat latch • Produce surface CAD model of features retaining seat latch in correct position • Evaluate effectiveness of design on 3D printed prototypes and pave tests

Results

• Proposed design put forward into volume production

Bottom line

In this project I had to improve ergonomics of the assembly with making the least possible number of changes to the geometry of parts. I calculated tolerance stack across the seat latch length and decided upon seat latch cable’s length. Then I modified existing design of retaining features to provide more secure hold of the cable. This project exposed me to some areas of engineering I haven’t experience before (ergonomics) and new material processing methods (plastic injection moulding)

OBR16 – Formula Student Rear Wing design for Formula Student car Objective

• Re-arrange existing elements of the Rear Wing assembly to increase downforce • Reduce mass of the assembly • Improve mechanical design of the assembly

Scope of work

• Produce parametric CAD assembly allowing for iterative adjustments of aerofoils angle of attack and stagger • Perform iterative CFD analysis of Rear Wing assembly. Establish stall angles of elements • Study influence of Rear Wing elements location on position of Centre of Pressure • Invent new internal structure for Rear Wing main plane

Velocity distribution around the wing before (left) and after (right) optimisation

Results

• Maintained level of downforce despite increased headrest interaction • 50/50 aero balance • 12% mass reduction due to lighter internal structure and smaller endplate

Bottom line

Above: Basic correlation of CFD results (wall shear stress) with actual package characteristics (flow separations identified by wool tufts) Right: Aerofoil shaped I-beams in wing’s structure.

This was my first serious design project. I was lucky enough to have very clearly defined constrains (re-use existing tooling for aerofoils), goal (achieve amount of downforce and manipulate Cp for 50/50 balance) and support – my work was supervised by one of senior students, currently F1 aerodynamicist. I took this very first opportunity to go an extra mile with my effort and designed new internal structure for aerofoil elements and optimised shape of the endplate using CFD analysis to reduce mass of the wing.

Oxford Brookes University Double Wishbone Suspension mechanical design Objective

• Deliver mechanical design of double wishbone suspension linkages

Scope of work

• Calculate loads experienced by assembly members: wishbones, clevises, fasteners • Design structurally sound linkages • Produce high quality 3D renders of the assembly • Design mechanism of camber adjustment

Results

• Developed Excel spreadsheet calculating loads in each suspension member based on geometry and load case • Awarded 1st class grade for the project

Bottom line

In this project I worked in a unique 4-member group with 4 different nationalities, different levels of engineering expertise and age (18-38).

From engineering point of view, I combined skills of basic static analysis of the system to determine loads acting in various driving conditions (bump, acceleration, braking, cornering and combined) and stress analysis which allowed me to decide on material selection and geometry required to withstand the stress in the system.

Koiranen GP Trackside Data Analysis and Composites repairs Objective

• Improve junior drivers understanding of vehicles behaviour within 4 race weekends • Ensure smooth execution of repairs of all composite bodywork

Scope of work

• Shadow race engineers: • Collect data and onboards after each car stint • Critically compare data against fastest driver’s traces and identify driver errors / corners to improve • Relay the above to the driver • Lead composite bodywork repairs • Train 3 members of staff in CFRP and GFRP wet layup technique • Execute necessary bodywork repairs during race weekend

Results

• Driver I was co-coaching, Vlad Atoev, achieved 2nd place in drivers classification (podium finish in 50% of the races)

Bottom line

This was arguably one of the biggest adventures so far. After my first year at Brookes, I was awarded with an internship at Koiranen GP, where I experienced working trackside. I learned how to read race car data, basics of race car set up and maintenance. Both parties were satisfied with the internship and I am proud to have integrated into the team within very short time and learned “behind the scenes” of a race weekend.

ISIS15-Formula Student Impact Attenuator development for Formula Student car Objective

Manufacture and test front crash structure for Formula Student car

Scope of work

• Build 3 CFRP and 4 balsa wood prototype impact attenuators • Design and build chassis representative steel fixture for crash tests • Design and build two piece, GFRP split mould for carbon pre-preg nosecone • Carry out dynamic impact tests and professional facility • Analyse data from the test and improve design of the prototype

Results

• Passed impact test within set deadlines which allowed the team to avoid penalties.

• Reduction of nosecone manufacturing time due to new, redesigned tooling.

Bottom line

I joined Formula Student immediately after enrolling at the University. I quickly gained trust of team members and assisted one of the senior students with development of front crash structure. My role entailed design of fixture used during the crash test that would limit deflection of anti intrusion plate mounted behind the crash structure. This project got me addicted to the pace of motorsport industry.

Parametric modelling: FS Front Wing Flapto-Footplate joint •

•

Idea: Elements were modelled to allow for iterative design of flaps and footplate surface, without having to constantly remodel the joint between two parts

Parts discussed are highlighted on the screenshot above with pale red and pink color

Features:

Parametric

Controllable

Flexible

Robust

Part is referencing both flap and footplate surfaces. Thanks to this, bottom part is automatically trimmed to the shape of footplate and top part is always C2 to flap surface. Part has got variable aerofoil: top aerofoil is always identical to flap aerofoil, whereas bottom aerofoil has identical chord and reduced camber (calculated)

Aerodynamically, bottom surface acts as an extension of Main Plane’s primary vortex tunnel. To control angle of expansion of this feature, curvature of the part is easily controllable with two sketches (both have only two numerical dimensions which simplifies iterative studies)

Part is mated in the assembly using 3D sketch which allows to change Angle of Attack, span of flat section of flap, stagger of Flap with Main Plane, all from assembly level.

Additional advantage is that any errors with other parts should not influence position of this model in space.

Part was modelled with minimal number of features to ensure quick rebuilds and minimise risk of errors.

Sketches used were dimensioned in a way preventing trimming surfaces “missing” each other