Control method of rigid-flexible coupling platform with single feedback and single drive

Abstract

The invention discloses a single-feedback single-drive rigid-flexible coupling platform control method. The method firstly limits the maximum acceleration of motion planning, and secondly separates the control signal into three types of control: feedforward, flexible hinge disturbance force and speed displacement deviation correction quantity. When the motion planning is reasonable, the equivalent dynamic model of the rigid-flexible coupling platform is an ideal rigid body without friction, and the control force is mainly the force of feedforward and flexible hinge. The velocity displacement deviation is mainly caused by the elastic deformation of the flexible hinge, and the main frequency component is the natural frequency of the flexible hinge, which can be filtered out by notch filtering. Since the ESO itself has a filtering function, there is no resonance component after superimposing the above three control signals. Through this method, the dynamic response equation of the platform is equivalently transformed into an ideal undisturbed form. This not only avoids the cumbersome and complicated model switching control, but also realizes high-speed and precise motion.

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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