Multi-objective optimal control allocation for a four-wheel-independent-drive electric vehicle

The four-wheel-independent-drive electric vehicle has potential superiority in improving operational efficiency and enhancing vehicle motion control performance by allocating different torques to four wheels. To achieve the energy optimization and to ensure the driving stability, a multi-objective optimal control allocation law is proposed, which composed of two steps of optimization. A pre-allocation law is firstly carried out for energy efficiency optimization, and then a reallocation law is performed using model predictive control to avoid the wheels from skidding. Simulations show that not only the energy optimization objective can be achieved in most cases, but also the vehicle stability can be ensured when tire friction is saturated.