Utveckling av kolfiberchassi till GiGtechs fordon Reborn

Sammanfattning: Shell Eco Marathon is a competition where the goal is to make a vehicle as energy efficient as possible. One team that compete in the competition is HiGtech, whose vehicle is using a frame of steel pipes. Because of that, their vehicle weight more than most of the competitors who uses carbon fiber monocoques. Therefore, in order to be able to compete with the best teams, a carbon fiber monocoque is required. The purpose with the thesis is to reduce the weight of HiGtech:s car and the goal is to develop a finished model for a monocoque. Included in the goal is also to develop a new steering function and engine bracket and new solutions for the wheels and brakes attachment to the vehicle. After a literature study, it was decided that the carrying details of the monocoque should be built by using a Sandwich construction to reduce the weight and factors that affects the strength was looked in to. Three concepts for the monocoque was developed using brainstorming, which was evaluated with results from Finite Element Analyses when the concepts was evaluated relative each other. After a winning concept was determined, it was further developed and dimensions and strength for the carrying details was set using Ansys ACP module where a safety against collapse could be determined. After the monocoque was developed, concepts for steering and engine bracket could be developed. The concepts was evaluated and a winning concept was chosen to be further developed and dimensioned. Solutions for the wheels and brakes attachment to the vehicle was made and dimensioned. A honeycomb-core with a thickness of 25 mm is needed. Two layers of carbon fiber is needed on the frame around the geometry is needed, one layer on each side. On the bottom plate it is needed two layers on each side. This will give a safety on 2,5 against structural collapse and a mass on 8,7 kg. The engine mount will have a safety clearance of 12. The torque rod will have a saftey on 5. For the front wheelbarrowing the safety will be 4 and for the rear suspension the safety will be 2. Since the modell for the body is not compatible whit Inventor could the strenght of the body not be calculated with. The bottomplate could be optimized further, which should decrease the weight furhter.