Development of a Lightweight Electric Light Duty Truck Structure

Finding room to package enough energy at today’s battery energy densities, while preserving performance and configuration requirements is a common problem for electric vehicles. This issue was recently addressed at General Motors by a small team utilizing agile concept development methods, constitutive material model development, and performance simulation tools to create a structural strategy for a family of unique electric light duty trucks. The desire to create a flexible architecture rather than a single vehicle, coupled with an underbody dominant, and rectilinear structural design space precluded any great topological novelty, so a basic principles approach was taken instead. A concept was devised whereby conventional truck frame rails were abandoned in favor of a series of three connected box-like structures along the length of the vehicle. For this to work effectively however, stable shear panels were required as a basic building block. Aluminum Foam Sandwich panels were adopted for this purpose which required a separate material characterization program using small specimens in a largely dynamic testing schedule. The knowledge from this step was scaled and applied to the virtual development of the concept. Coupled with parametric finite element mesh generation tools, and modified models of vehicles in similar segments, a proof of concept was generated that could be used as the basis for downstream vehicle development.