INDUSTRIAL ROBOT HAVING A DEVICE FOR TEACHING A MOTOR-DRIVEN ARM WITH VARIABLE SERVO-CONTROL

摘要

Disclosed is an industrial robot of the type wherein the robot arm is directly driven by a motor. A position encoder generates a signal representative of the actual position of the arm and a manually controlled position entry switch is operable during a teaching mode. When the arm is manually moved to a desired position, a memory controller responds to the operation of the position entry device by storing the actual position signal in a memory as a target position signal, and reads the stored signal during a playback mode. A servo-control system responds to the actual position signal from the encoder and the target position signal from the memory by controlling the motor so that the actual position of the arm approaches the desired position during the playback mode. The output of the servo-control system is decreased during the teaching mode to render the arm manually movable to the desired position and is increased during the playback mode. Alternatively, the servo-control system is disabled during the teaching mode to permit the robot arm to be manually moved to the desired position and enabled during the playback mode.