With the previous 2013-14 season seeing us running a modified version of the 2012-13 car, our primary target for the 2014-15 season was to see out our original intention from the previous season of an entirly new design. The magnitude of this challenge was significant but having got a head start by beginning work on the new chassis and components during the 2013-14 season, it was a challenge we felt that we could address. We also belived that this drive for an entirley bespoke design was one that was necessary to demonstrate the many lessons we had learnt from the first 3 years of participation in the competition.
Once again extensive use of computer aided design (CAD) was vital in making these engineering advancements. By designing in the virtual environment we were able to improve each component in terms of weight and functionality, whilst still ensuring that the whole assembly is fit for the purpose intended. We had targeted several key areas for improvement over the previous car such as chassis, with a new rear end design which dropped the CBR 600 engine by 50mm closer to the ground, consideribly lowering the new car’s centre of gravity. The method of attaching our suspension components to the chassis was also addressed in the new design, in order to improve the manufacturing and assembly of these critical components. We also changed our chassis jigging method from the initial design used in the 2013-13 season, this combined with the laser profiling of our tubes and the kind support of key sponsor Z-Cars, who used their TIG welding expertise to weld the bulk of our frame, ensured that our new chassis was lighter, stiffer and manufactured to a higher tolerance than ever before.
The picture below shows the chassis back in our department workshop in early 2015, where we had begun to MIG weld on additional fixtures such as bulkheads, pedal box, seat and harness supports, engine mounts and brackets etc. We extensively utilised CAD, designed sheet metal components and laser cutting to produce intricate self-jigging brackets and plates. This advancement in design and manufacturing was immediately benificial as it was shown to massively speed up the assembly process as the resultant components integrated seamlessly with the chassis.
The next big challenge we wanted to address for the 2014-15 season was the bespoke design of all of our suspension and drivetrain comonents. In previous
year’s we had used many OEM components for cost cutting and design simplicity, the consequence of this decision was excesss weight and packaging issues.
With OEM components, most derived from automotive applications, the components were intended for much more powerfull and heavier products than our Formula Student car. By designing them ourselves we could remove this unecessary weight and optimise the components to our own specifications. Furthermore we previously purchased some drivetrain components from the USA, due to not being able to find a local supplier to meet our needs, which cost us a lot in import TAX and put more constraints on us being able to aquire spares if needed. The image below shows most of the new components we designed for this years car which we had CNC manufactured in Hull. Seen here is our new front and rear uprights, new differential swing arms, an entirely new live spindle front hub design which removed the need for a heavy fixed steel stub axel, bespoke drive flanges and sliding spline fitment drive axels, as well as our new rear suspension beam assembly with integrated brake light mounting. This amount
of bespoke design accounted to an immense design effort. The weight saving and improved packaging achieved through introduction of these new designs presented such a significant leap forward in the engineering professionalism demonstrated by our new car that it was entirely worth the extra effort required.
Another new significant design challenge this year was the target of a completely new exhaust packaging solution. The goal was to replace the top mounted twin silencers used in previous years with a single bottom mounted silencer. This presented a significant design challenge due to the very tight packaging restraints, however the rationale behind the new concept was that by having a single central rear silencer we would firstly reduce the overall weight of the system, by immediately removing one silencer, but furthermore that the remaining weight would be shifted lower to the ground, further improving the centre of gravity. An additional benefit was that the extra space reclaimed at the back of the car created more potential to accomodate and optimise the new rear suspension assembly. In order to realise this goal we had to once again meticulously design the exhaust system in CAD, ensuring that a good gas flow was maintained whilst maximising t
he clearance between moving components such as suspension and drivetrain.
Once we arrived at a complete solution we worked with Zorstec to manufacture our custom design to our specifications. We were also extremely grateful this year for a sponsorship agreement with Zirotec who coated our completed exhaust with their high performance ceramic coating, ensuring that the heat of the exhaust system is maintined internally, allowing us to package it more tightly without the fear of exhaust heat transfering to other heat-critical components.
One remaining hurdle for our team during the 2014-15 season was the need to manufacture some new bodywork and a new seat. After using thermoformed plastic in the first two years and with the unfortunate withdrawl of our bodywork partnership with Lincross and Progressive CNC in the 3rd year, where we ran a simplistic two dimensional panel arrangement, we decided it was time to take the manufacturing of our bodywork into our own hands. With new sponsors Easy Composites on board we got discounts on composite materials and perfiferals needed to manufacture our own panels but we still had a lot to learn. With no access to large bed CNC equipment we needed to break our new bodywork designs down into pieces small enough to machine in-house, which we then bonded together to form our bodywork moulds. The next hurdle we faced was finding an oven large enough to cure our pre-preg carbon fibre parts in, unfortunately we were
unable to aquire an oven large enough to manufacture our largest panels suchs as the side pods and front panel. However thanks to the Chemisty Department, we were able to get access to an
oven large enough to cure our nose cone and radiator ducts, yielding our first ever in-house carbon fiber components. For the larger panels we used traditional glass fiber manufacturing methods but regardless this was still a significant step forward for us, saving in total approximately 15kg of our previous vaccuum formed plastic panels. We also extended our drive towards composite manufacturing to other components of the car, such as our new seat design and underbody, where we utilised CAD once again to design a complex jigsaw puzzle of 2D profiles of pre-cured foam covered with carbon fibre sheet material. We cut the sheet material to true scale templates generated from the CAD designs and bonded them with structural adhesives, this allowed us to benefit
from the weight saving of carbon fibre without the need for an autoclave or large industrial oven.
All of these advancements in the design and fabrication of the 2014-15 car enabled us to turn the CAD model shown above into what was easily our most advanced car to date shown below. Regrettably however, all these new developments took a substantial toll on our competition readyness. With Silverstone looming we had the car built just in time this year, however we were unable to test the engine. As we were using the same engine model as previous years we had hoped that our previous engine map would be enough to get us running but we were aware that with a new exhaust and new intake system it would be far from optimal. Unfortunalty it turned out to be much worse than than and our car simply refused to run reliably. At the competition we sucessfully passed all of the static scrutineering challenges, which was in itself an achievement to be proud of, as it was said by many to be one of the toughest years yet in regards to scrutineering. With our new car deemed safe to race our next hurdle was to pass the noise test, our new and novel exhaust design was gathering a lot of attention at the competition and everyone, including ourselves, were keen to see if it would pass the strict new noise regulations. Without having been able to fit in any dyno testing and development time we had a significant challenge to try and statically tune our new car in-situ at the noise test preparation area. We worked relentlessly refusing to give up untill we had it running well enough to pass the test, however it seemed like everything was against us including the British weather, as the heavens opened and the nosie test area was closed, meaning we lost our window to proceed through the noise test and on to the final brake test.
The picture below shows our new car in the noise test area just after the elements signaled an end to our 2014-15 season. Dejected and drenched it was a dispointing end to what was such a significant step forward for our team. Eventually when the rain cleared we gathered our car and equipment packed up our garage and held our heads high in the knowledge that we had given this years competition our all. It is always difficult to have such a undesirable result at the competition, especially given how far along we were, knowing how far we had come over the previous year and how much potential we were aware that our new car. This meant that we could take pride in the knowledge that all these advancements put the new team in a much stronger postion for next year. We are confident that much like the Mercedes-Benz F1 Team, this year’s challenges where necessary to shape the future of the project and we hope that similarly we can demonstate this this tactical decision to invest so heavily in technical advancements will prove to be vital for long-term success.