Abstract
Since timing belt drives have the advantages of low costs and accurate transfer characteristics, they are widely used in industrial machines and office automation equipment. However, timing belt drives have problems with periodic transfer variations caused by eccentric pulleys, interlocking belt and pulley teeth etc. Though it can be said that high feedback servo gain is effective in suppressing the periodic variations, the high gain easily makes the system unstable because of the elasticity of the drive system and the modeling errors. In this paper, we propose a control technique that suppresses periodic variations using a disturbance observer. First, we analyzed the mechanism of the generating variations caused by eccentric pulleys that are the most influential of all. Considering the periodic variations, we suggested the sinusoidal model for disturbances. The by implementing I-P speed control with disturbance compensation using the estimated disturbances from the observer, we verified the effectiveness of the disturbance compensation method.
