A Lateral Motion Controller for Smart Chassis Addressing Structural Uncertainty

In order to make lateral motion robust and stable for smart chassis, a lateral motion controller is proposed in this paper taking structural uncertainty into account. Firstly, a new lateral error model is developed to describe the lateral motion problem. Secondly, the kernel of the lateral motion controller is active disturbance rejection control method, that is, a second order linear tracking differentiator is embedded between lateral error model and first order linear active disturbance rejection control (FO-LADRC). And every module of the lateral motion controller has been designed in detail, which contains first-order linear tracking differentiator (LTD1), second-order linear tracking differentiator (LTD2), linear extended state observer (LESO), and linear state error feedback (LSEF). Finally, six typical scenarios with two conditions are designed to validate the controller referencing to the test standard, considering the structural uncertainty, including wheelbase length and steering ratio. The results illustrate that the developed lateral motion controller has excellent performance in both robustness and stability compared with pure pursuit and FO-LADRC when there are structural uncertainty in wheelbase length or in steer ratio.