ENHANCING THE STABILITY OF UNMANNED GROUND SPORT UTILITY VEHICLES THROUGH COORDINATED CONTROL UNDER MU-SPLIT AND GUST OF WIND

Abstract

This study describes a comparative study of steering and yaw moment control manoeuvres in model predictive control (MPC) and linear quadratic control approaches for path following unmanned vehicles for different control manoeuvres: two-wheel steering, four-wheel steering, and direct yaw moment control. We then propose MPC with a proportional-integral (PI) controller for the coordination of active front steering (AFS) and active braking system, which particularly highlights direct yaw moment control (DYC) manoeuvres. Based on the known trajectory, we tested a vehicle at middle forward speed with the disturbance consideration of the road surface adhesion and the wind for a double lane change scenario in order to follow the desired trajectory as close as possible, minimizing tracking errors, and enhancing vehicle stability and drivability. We compared two different controllers; i) MPC with PI of an AFS and, ii) MPC with PI for coordination of AFS and DYC. The operation of the proposed integrated control is demonstrated in a Matlab simulation environment by manoeuvring the vehicle along the desired trajectory. Simulation results showed that the proposed method had yielded better tracking performances, and were able to enhance the vehicle’s stability at a given speed even under road surface coefficient and wind.

Keywords

• Unmanned ground vehicle
• Model predictive control
• Proportional- integral controller
• Path following control
• Road surface
• Wind gust