Multivariable lateral control of an off-road vehicle operating on sloping grounds

This paper proposes an optimized lateral control design of a two-steering-axle off-road vehicle. An extension of the well-known bicycle model is introduced that considers two steering axles and the slope of the local ground. Lateral deviation controllers are thereby synthesized to quantitatively evaluate the use of multiple steering angles. The proposed multi-input multi-output feedback controllers originate from a H2/Hinf multi-objective synthesis, achieving optimum trade-offs between performance and robustness. Three controller architectures are considered (depending on actuation pos-sibilities) and compared qualitatively and quantitatively. In addition, realistic simulation results are analyzed using a non -linear simulator that considers the fine modeling of sensors and actuators (e.g., hydraulic actuator). The results are promising and will be the subject of an experimental validation project.