Contour error controller for multi-axis motion system and control method thereof

Abstract

The invention discloses a contour error controller for a multi-axis motion system and a control method thereof. The contour error controller comprises the multi-axis motion system. Each axis of the multi-axis motion system is provided with a sliding mode variable structure controller and an extended state observer. The sliding mode variable structure controller can obtain a control signal based ontracking errors of each axis; and the extended state observer can observe observation variables for producing position signals, velocity signals and disturbance signals of each axis. The invention proposes a contour error control algorithm based on extended state disturbance observation for multi-axis linkage control system formed by three-axis permanent magnet linear synchronous motor servo drives, thereby effectively reducing tracking errors and contour errors. The extended state observer is used to observe the disturbance signal to reduce influence of the disturbance, and a sliding mode variable structure control algorithm is combined to form a uniaxial trajectory tracking controller, thereby ensuring uniaxial tracking accuracy and robustness; and through a cross coupling controller, the problem of multi-axis coordinated movement is solved and multi-axis contour control precision is improved.

Description

technical field [0001] The invention belongs to the technical field of multi-axis coordinated motion in the field of numerical control machine tool processing, in particular to a contour error controller of a multi-axis motion system and a control method thereof. Background technique [0002] With the rapid development of modern industry, the precision requirements for multi-axis manufacturing systems are getting higher and higher. In order to improve the contour machining accuracy, many experts and scholars are devoted to studying various single-axis tracking control strategies, thereby indirectly improving the contour motion control accuracy. [0003] However, this traditional contour controller based on single-axis uncoupling control cannot fundamentally solve the problem of contour control. For example, when a certain axis is disturbed and a large error occurs, other axes still think that the axis is running normally, and do not take necessary measures to reduce the imp...

AI Technical Summary

Problems solved by technology

[0005] With the development of contour control technology, the complexity of the cross-coupling controller increases, the robustness and stability are enhanced, and the degree of coordination is also improved, but the anti-interference ability is general

Since the machining trajectory of the multi-axis motion platform is the result of multi-axis coordinated movement during the machining process, it is easily affected by external disturbances, which affects the position accuracy and contour accuracy of the CNC machining system.

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