Optimization Process for Off-road Vehicle Shock Absorbers

The purpose of this paper is to demonstrate a process to automatically modify and optimize a damping curve for a specific road input. Off road race vehicles are required to maintain high speeds over difficult terrain. This requires large wheel displacements, and shocks tuned to properly damp wheels motions using available wheel travel. Selection of proper damping values allows full use of available suspension travel while minimizing loads and accelerations experienced by the vehicle and driver. Using Altair's MotionView and HyperStudy, a process is demonstrated where a damping curve can be modified based on specific constraints and performance criteria. A full vehicle MotionView model of a generic off-road race car will be simulated driving over a large obstacle. Using optimization techniques within HyperStudy, the characteristics of the damping curve will be modified so that pitch displacement and vertical accelerations on the vehicle and driver are minimized. This demonstrates a basic process that can be expanded to include multiple events, constraints, and objectives.