The research of contour error with PID control based-on disturbance observer

In the motion control system, the differences of the dynamic characteristics of each axis are the main reasons for the contour error. We can design a high performance controller for each axis to improve the dynamic characteristics and reduce the contour error of the system. In order to reduce the contour error of multi-axis motion system, a PID control strategy based on disturbance observer is proposed in this paper. That is, through estimation of the internal and external disturbance of each axis by using disturbance observer, the disturbance acting on each axis can be compensated. So each axis unforeseeable & unmatchable problems for dynamic characteristics are solved. Simulation results demonstrate that the algorithm is feasible and valid.