Path planning and tracking of a 4WD4WS vehicle to be driven under force control

The aim of this paper is to investigate the possibility of developing a system where forces at the wheels of a ground vehicle are controlled to guide the vehicle along a predetermined path. Any deviations from the desired path is handled using Bézier curve segments that put the vehicle back on track. The Bézier curve segments determine the necessary forces at the wheels. The future aim is to implement independent force control at each of the drive/steering modules of the vehicle. The vehicle is considered to be a rigid body with known inertia and mass. The paper presents path generation using Bézier curves, the extraction of desired forces and the determination of desired steering and propulsion to achieve the desired forces at the wheels of the vehicle. The forces and the control inputs such as the steering angles are then applied to a four wheel driven and four wheel steered vehicle subjected to slip in an open loop setting. Note that this paper does not address the force control issues. Simulation data are generated to validate the proposed methodology.