Research on Contour Tracking Control Method of Three-axis Motion Platform

To solve the problem of error calculation distortion in traditional error modeling, an improved contour prediction error model is proposed. The contour error is determined by tracking error, target trajectory point, and historical command trajectory point. At the same time, to reduce the load disturbance and contour error of the platform during trajectory tracking under high dynamic conditions, a compound controller with feed-forward pseudo-differential feedback (PDFF) control and tangent contour compensation control is proposed. The PDFF controller is used to improve the robustness of the system, and the tangent contour compensation controller is used to reduce the influence of the contour error model on contour accuracy and realize real-time compensation of contour error. The simulation results show that the designed composite control system can estimate and compensate for the contour error in real-time, and has high estimation accuracy and fast response speed, which meets the performance requirements of high precision contour tracking of the three-axis motion platform.