Vibration suppression for wafer transfer robot during trajectory tracking

Abstract

In order to solve the vibration during the process of transferring wafers and achieve the purpose of transferring wafers accurately and stably, the wafer transfer robot dynamic model was modelled and the strategy of vibration suppression based on input shaping was proposed. Based on the characteristics of wafer transfer robot, ZV input shaper and skewed shaper was designed to solve the single axis's vibration caused by timing belt and harmonic reducer, and most importantly, the vibration of end effector during trajectory tracking was suppressed with input shapers using multi-modal system cascade method in the Cartesian space. Through comparison of different effects during the straight-line trajectory tracking in different spaces, the experiments demonstrated that the input shaping in Cartesian space suppressed vibration of end effector and improved the accuracy of trajectory tracking.