SYSTEM FOR CONTROLLING SERVOMOTOR.

摘要

A system for controlling a servomotor in which a controlled system is a servomotor for driving a mechanical system of low rigidity such as a robot arm, and the control error of the torque of command value of the servomotor is corrected according to the estimate of a disturbance torque applied to the mechanical system. The system comprises a calculating means (15) for calculating an actual acceleration (a) of the mechanical system from its actual velocity (VL), a signal converting means (16) for converting the torque command of a servomotor (3) to an estimated acceleration (an) of the mechanical system based on the torque command, and an estimating means (18) for estimating the disturbance torque applied to the mechanical system by calculating a deviation ( DELTA a) of the output of the calculating means (15) from the output of the signal converting means (16). Thereby, the effect of the disturbance changing nonlinearly due to a spring constant and a damping constant is suppressed.