Investigation of the Non-Convex Force Constraints Imposed by Individual Wheel Torque Allocation
This paper explains the non-convex tyre force constraints on electric vehicles with individual drive. Given demands from a motion planning on a top level from the vehicle hierarchy, the task to allocate forces to each wheel corner is considered as a mapping process from a global vehicle level. One important role of the allocator is to deliver solutions even if the requirements arising from motion planning are not physically feasible. To secure vehicle stability, fundamental allocator requirements are formulated. However, more demands are needed to avoid undesired vehicle behaviors. These demands, which belong to
the optional allocator requirements, are described. Given the force constraints and the allocator requirements, solutions of the allocation problem to four electrical
machines are solved by non-linear programming.