2000 年 66 巻 1 号 p. 122-126
Linear motor feed drives are considered as the ideal drives with no-transmission, no-backlash and smooth motions. But if they are applied to dynamically complicated machines such as machining centers or cantilever type XY robots, the servo systems are influenced by the structural vibrations. The vibrations inspired by tracking motion aggravate the motion and position accuracy. Some of them are detected by position sensors and destabilize the servo loop. This paper deals with the design method of stabilizing controllers for the linear motor servo drives under the influence of structural vibrations. The feed drives are modeled and analyzed taking structural vibrations into account, and stabilizing controllers are designed based on the modem control theory. A reduced order controller is also designed and compared to the classical PI compensators in terms of servo characteristics. Observer based full state feedback controller and local state feedback controller are found to be effective through simulation and experiment.