Design and Implementation Based on Backstepping for Tracking Control of Nonholonomic Mobile Robots

Differential driven mobile robots are typical nonholonomic systems, involving system nonlinearity, which brings challenges to trajectory tracking control. We propose a kinematics control strategy based on backstepping to solve the nonlinearity of the system in this paper, in which the system is divided into three subsystems and two virtual control variables are derived to design the controller. Benefiting from this improvement, the design of the Lyapunov function is simplified and the nonlinearity is solved effectively. In terms of LaSalle invariance theorem, global asymptotic convergence of the provided control scheme is achievable. Furthermore, the effectiveness of the derived control method is validated in both the co-simulation of MATLAB and ADAMS (performed on a differential driven wheeled mobile robot) and the experiment (implemented on a tracked mobile robot). Results indicate that the controller is effective to make the nonholonomic mobile robots converge to reference trajectories in finite time.