Research On Position&Force Control Based on Voice Coil Motor

Abstract

In this paper, we studied the Position&Force servo control of the voice coil motor commonly used in semiconductor packaging equipment and analyzed its Position&Force servo control switching strategy. System identification is the basis for high-speed, high-precision motion control. We use the frequency domain identification method to identify the voice coil motor system. The frequency domain identification method uses sine sweep frequency and PRBS method to compare and verify. Feedback and feedforward servo control structures are used to ensure quick response and precise control of voice coil motors while ensuring system stability. In the feedforward control, we use an iterative learning control method. In semiconductor packaging equipment, the movement of the voice coil motor has always been a similar process cycle. Iterative learning control (ILC) has prominent control effects in situations where control objectives and external disturbances are periodic or repetitive. The iterative learning control algorithm is applied to the feedforward plus feedback servo control structure of the voice coil motor. From the actual effect point of view, the trajectory tracking ability of the voice coil motor during high-speed motion is significantly increased. The voice coil motor servo control algorithm described above is written on the DSP and verified on the motion control card. The experimental results show that the above servo control algorithm realizes the high speed and high precision motion control of the voice coil motor.