Single feedback single drive rigid-flexible coupling platform control method

Abstract

The invention discloses a single feedback single drive rigid-flexible coupling platform control method, which firstly limits the maximum acceleration of a motion plan, and secondly separates control signals into three control quantities of feedforward, flexure hinge disturbing force and speed displacement deviation correction. When the motion plan is reasonable, the equivalent dynamic model of a rigid-flexible coupling platform is a frictionless ideal rigid body, and the control force is mainly the feedforward and the force of a flexure hinge. The speed displacement deviation is mainly causedby the elastic deformation of the flexure hinge, and the main frequency component is the natural frequency of the flexure hinge, which can be filtered by notch filter. Because the ESO itself has a filtering function, there is no longer a resonant component when the above three control signals are superimposed. By this method, the dynamic response equation of the platform is converted into an idealundisturbed form. The tedious and complicated model switching control is not only avoided, but also the high-speed precision motion is achieved.

Description

technical field [0001] The invention relates to the technical field of motion control, in particular to a single-feedback single-drive rigid-flexible coupling platform control method. Background technique [0002] In the field of high-speed precision motion control, there is a friction dead zone in the motion platform based on mechanical guide rails, so the control accuracy can only reach the micron level. In the case of higher precision control, it is necessary to use air suspension, magnetic suspension or static pressure guide rail to reduce or even eliminate the friction effect. A wide range of electronic manufacturing technology fields. [0003] Rigid-flexible coupling platform cleverly combines the characteristics of large-scale rigidity motion of linear platform and friction-free precision motion of flexible hinge. At the zero-crossing point of speed, the elastic deformation of flexible hinge is used to avoid friction dead zone and realize the compensation of friction...

AI Technical Summary

Problems solved by technology

Due to the introduction of flexible hinges, the bandwidth of the system will be reduced and low-frequency vibrations will be caused. Using traditional PID control, after being amplified by the controller, the control signal will produce greater fluctuations, which will further aggravate the vibration and affect the control accuracy. If the control signal is directly controlled The filtering process will also filter out the information of the flexible hinge and the motion planning command, so the control signal will not work at all

In addition, in order to protect the driver, the control amount entering the driver is generally limited to prevent it from exceeding the limit of the control amount, which leads to the fact that when the disturbance becomes larger, the driver’s capacity may be limited before it reaches the maximum, so the disturbance cannot be completely offset

Moreover, due to the inconsistent control laws in the process of large-scale motion and micro-motion compensation, it is necessary to switch models for control, which makes the control process very complicated

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