Robust Lateral Motion Control for In-Wheel-Motor-Drive Electric Vehicles With Network Induced Delays

In this article, a robust control scheme for an in-wheel-motor-drive electric vehicle (IWMD EV) is put forward to enhance vehicle lateral stability considering network-induced time delays. A robust sliding mode controller (RSMC) is devised, and the derived control law is partitioned into two portions, i.e., the continuous and discontinuous parts. A Linear-Quadratic-Regulator (LQR) problem with network-induced time delays is formulated with the objectives of minimizing the reference states tracking errors and reducing the control efforts. Then, it is transformed into an iterative solution derivation of a two-point boundary value problem without delays, and the derived solution is obtained and constitutes the continuous part of the control law. Meanwhile, the global sliding mode theory is applied to deriving the discontinuous part of the control law, which has robustness to vehicle parameters variation and modeling uncertainties. The proposed control scheme exhibits better performance in dealing with network-induced time delays compared with the original optimal LQR controller in simulation and Hardware-in-the-Loop (HIL) tests.