An Optimal Torque Vectoring Control for Vehicle Applications via Real-Time Constraints

A generalized integrated control strategy for vehicle dynamics using an optimal torque vectoring control approach is extended in this paper. The central objective of this approach is to generate optimal additional tire forces and yaw moment over the vehicle through the application of individual wheel torque to keep the vehicle on a target path. This is achieved by minimizing the error between the actual and target forces and moment at the center of gravity ( CG). In this paper, this methodology is extended to a constrained optimal control approach that handles additional real-time constraints, which has several vehicle control applications. An online optimization strategy is used to solve the resulting constrained optimization problem that gives the necessary tire force adjustments at the tire level. Some typical applications are 1) differential braking on all wheels, which is applicable to both electric and conventional cars and 2) hybrid torque vectoring on the front wheels and differential braking on the rear wheels. Both simulations and experimental results show the usefulness of this approach of handling constraints with this optimal torque vectoring control.