Structural analysis of a composite monocoque chassis for use in a high performance electric vehicle.

Abstract

The adoption of electric vehicle technology is becoming more prevalent, as society strives to reduce the negative impact of greenhouse gas emissions and focuses on a sustainable future. This thesis details the design and structural analysis of a carbon composite monocoque chassis for application in a light-weight, high-performance electric vehicle for a South African market, based on the fundamental principles of automotive vehicle design. Handling characteristics and the design impacts they have on the decisions made in developing a vehicle chassis were explored. The two-dimensional geometry of the chassis structure was developed in the Siemens NX design environment, taking into account the spatial requirements of the mechanical and electrical system components, as well as occupant ergonomics. A zonedbased approach was taken in defining the composite layup for the chassis panels, using material data for locally obtained fabrics and epoxy resin. The chassis’ composite lay-up configuration was developed using several static load cases, simulating operational loading, as well as extreme loading arising in certain accident scenarios. The composite structure was analysed, with the first ply composite failure criterion being used to predict failure in the constituent materials. Design refinement was undertaken until the failure criterion predicted structural survivability for all the extreme loading cases considered.