Development of car for Eco-marathon

Abstract

The objective of this project has been to develop the front suspension and certain parts of the in-wheel motor of NTNU’s new car for Shell Eco-marathon, as well as assisting other team members. NTNU has participated in the Urban Concept class in the European race every year since 2008, with one world record (2009), twice second place, and one failure (2010). The original PureChoice car (renamed DNV Fuel Fighter during the second year) was powered by hydrogen, but the power source was changed to battery this year as a team decision to avoid the pitfalls and challenges with working with a hydrogen fuel cell. Shell Eco-marathon 2012 moves the competition from the typical, smooth, race track to the city streets of Rotterdam. This requires a complete redesign of the suspension to handle the new type of road, since the previous designs have been completely rigid. By not only upgrading the suspension, but also building a completely new car body, new and better mounting points for the suspension could be made and realize fully damped suspension on all four wheels. The new motor specification also allowed the in-wheel motor to be made both lighter and more compact. This work is part of the collective work of more than ten engineering students at NTNU where I have been working towards an earlier delivery of a thesis than the rest of the team because of starting my thesis during the fall. My main responsibilities were in the beginning only the front suspension, with some shared responsibility of the rear suspension. After sketching and presenting a CAD model of how the new motor wheel could be constructed I also became much more involved with the design of the motor wheel which will be lighter and more compact than the previous inwheel motors. This report is divided into three sections – the first discusses the front suspension, the second discusses the mechanical motor design, and the third is a collection of appendices with technical data. All illustrations are self-made unless stated otherwise.