Adaptive Control Strategy to Steer and Drive an Autonomous 4ws4wd Ground Vehicle

Abstract

Autonomous vehicles are equipped with an increasing number of actuators to actively control the longitudinal and lateral dynamics of the vehicle. Amidst difference in terrains and roads that an autonomous vehicle drives through, precise coordination of the available actuators and effectors is needed to ensure an Autonomous Ground Vehicle (AGV) has improved manoeuvrability, accuracy and controllability. The increased number of actuators in a four-wheel steer and four-wheel drive (4WS4WD) architecture renders the control of the vehicle a challenge as the system becomes highly nonlinear. The control of an over-actuated, nonlinear and highly coupled system demands a superior control strategy. The controller should steer and drive the AGV to accurately track a path. The research proposes an adaptive MPC uses a linearized and a plant model updated at every instant. Preliminary results of the controller show that it bears potential to guide the 4WS4WD AGV to track a pre-defined path with minimal errors. Key Words- Adaptive MPC, Autonomous Ground Vehicle, Control, Drive, Steer.