Active Shimmy Control Method for Driverless Electric Vehicle Considering Unknown Sensor Measurement Error and Nonlinearities

The driverless electric vehicle with electric wheels may generate the front wheel shimmy phenomenon more easily. How to mitigate or even eliminate the shimmy phenomenon by active control method is necessary. The current active shimmy control methods do not consider the sensor measurement error. But the sensor measurement error always exists in practice because of sensor design, manufacturing, and external disturbances. Therefore, this paper investigates this issue. Firstly, a one-degree-of-freedom shimmy model of the front wheel is built. The dynamic function of this model is obtained via Lagrange’s theorem. Then, the shimmy control system with unknown sensor measurement error and nonlinearities is presented. A dual domination control method is proposed to construct a linear state observer as well as an output feedback control law for the shimmy control system. By the Lyapunov method, the designed controller is proved to stabilize the shimmy system globally asymptotically. Finally, simulations are carried out to verify the effectiveness of the one-degree-of-freedom shimmy model and proposed dual domination control method.