Abstract: Sideslip angle estimation is the key technique of vehicle stability control system. For electric vehicle, the information of driving torque and braking torque on wheels can be fully utilized to calculate the longitudinal force on the tire. If the longitudinal slip of the tire is large enough, the lateral force on the tire can be expressed with the longitudinal force on the tire and the tire slip angle. If the longitudinal slip of the tire is small, the nonlinear tire model is locally linearized. In such way, the two degrees of freedom vehicle model can be simplified to a linear model, whose state variable is the vehicle lateral speed and can be used to estimate the sideslip angle of the vehicle. Simulation results show that the estimation accuracy of the sideslip angle with the linear estimation model is high enough, and its dependence on the road surface friction coefficient is small. In addition, the calculation is simple due to the linearity of the model. The estimation method can be applied to the vehicle stability control system.

Key words: vehicle engineering, sideslip angle estimation, linear estimation model, stability control, Kalman filter