Adaptive integral backstepping motion control and experiment implementation

A novel adaptive nonlinear controller based on backstepping with an integrator is proposed for motion control systems. Backstepping is a practical nonlinear control scheme based on a Lyapunov design approach, which can therefore guarantee the convergence of the position tracking error to zero. The authors utilize the integral action in the backstepping to increase control action in the steady state against the disturbance. Adaptation schemes are designed to estimate the inertia variation and load disturbance in the motion control systems, in order to compensate their negative effects in the control system design. The proposed backstepping scheme is being tested on a motion control platform that is based on a new motion control product from Rockwell Automation. From the simulation results and current experiment results with focus on performance comparison with a conventional nested PI control scheme, the system's trajectory following ability is significantly improved, which proves the effectiveness of the proposed backstepping controller.