Electronic Differential Control with Vehicle State Observer Based on Extended Kalman Filter

The growing demands for high level of energy efficiency have given much new impetus to the development of electric vehicle in Agricultural Machines. To improve the performance of the state observer for an 8-DOF four-wheel vehicle, a state observer based on the Extended Kalman Filter is proposed. With the observer, the tire-road forces and the vehicle roll velocity are estimated accurately according to the simulation results. With the consideration of the nonlinear characters of tire and electric vehicle, the electronic differential controller is proposed to select the wheel slip ratios as the control tracking variables and distribute the torques to ensure the steering stability by using modified exponent approaching sliding mode control method. The proposed electronic differential controller is robust to improve the handling performance and control response of electric vehicle with the numerical verification.