Basic Study on Analysis and Suppression of Inverse Response Caused by Feedforward Friction Compensation of Ball-screw-driven Stage

Abstract

Ball-screw-driven stages are often used as feed systems of machine tools. A problem of tracking control of the stages is rolling friction, which degrades tracking accuracy around the velocity reversal point and causes a large tracking error called a quadrant glitch. Although the model-based feedforward friction compensation effectively reduces the tracking error, the compensation often results in an inverse response, which is the tracking error in the direction opposite to the quadrant glitch. This study aims to provide an analysis and a suppression approach to the inverse response. First, the inverse response is analyzed through the simulations. Next, a suppression approach of the inverse response is proposed. In the proposed approach, a step input is injected and cancel the inverse response. The proposed approach is evaluated through the simulations and experiments.