Optimized Rear-Axle Concept for Battery Electric Vehicles: A Show Case Study for New Suspension Development Methods

Journal article, 2022

One of the main challenges for battery electric vehicles (BEV) is a sufficient range. Therefore, a maximized battery volume is desirable in any recent vehicle concept. Suspension, as one of the largest subsystems, has a significant impact on that. Starting from a conventional car with an internal combustion engine (ICE), a suspension is developed to fulfill new packaging requirements for BEVs, while at the same time maintaining typical requirements concerning driving dynamics. The objective of this study is to use automated methods for suspension development to develop a new steerable suspension concept for an electric propulsion system. The suspension concept was optimized for premium cars with large battery sizes. Moreover, advanced active systems such as air springs and active rear wheel steering with large steering angles were also considered. The concept proposes a packaging solution with a well-tuned kinematic performance which meets typical tuning philosophies. In order to address the resulting high complexity, newly developed methods were used. The kinematic optimization was done with an innovative method, which automatically proposes new hard points, depending on the given requirements. For the design, simplified models were used to represent the shape of sophisticated parts. Therefore, it was possible to automatically judge whether a kinematic concept is feasible from a packaging point of view. The results show, that the new suspension concept can handle the challenge packaging issues and complex kinematic requirements.