Independent wheel steering control design based on variable-geometry suspension

The paper presents the control design of an independent wheel steering system for in-wheel electric vehicles. The steering of the wheels is based on the variable-geometry suspension control, which influences the camber angle and the scrub radius of the wheel. A nonlinear formulation of the variable-geometry suspension is derived, which is validated through a high-fidelity suspension model. Furthermore, the impact of the independent steering in the lateral model of the vehicle is incorporated. In the paper the robust control design of the independent steering system in a hierarchical structure is presented. The trajectory tracking of the vehicle is guaranteed by the robust H∞ control, while the intervention of the variable-geometry suspension is designed based on the Linear Quadratic theorem.