Joint Estimation of Center of Gravity Position and Mass for the Front and Rear Independently Driven Electric Vehicle with Payload in the Start Stage

This paper proposes a parameter estimator for four-wheel-independently driven electric (4 WID) vehicle with in-wheel motors. The mass and location of payload have great impacts on the stability and maneuverability of lightweight vehicles (LWVs). Fast, effective and real-time parameter estimator can make the existing controller adjust the changed parameter caused by additional payload. The proposed estimation method includes three parts with two calculation methods: the estimation of the angular acceleration of wheels, the vertical forces of tires, the vehicle parameter with payload, and the methods of Kalman Filtering (KF) and the recursive least squares method with a variable forgetting factor(RLS-VFF). The prototype of 4 WIDs LWV is the electric ground vehicle which driving torques can be controlled independently by four in-wheel motors. The simulation result is satisfied and the proposed estimator can be used to estimate the vehicle parameters.