Model follower control apparatus

Abstract

An apparatus for model follower control of a robot. The apparatus comprises a source for generating target position data representing a target position for the robot, and an operation pattern generator responsive to the target position data for calculating target angular position data representing target angular positions of the robot for respective control periods. A step input calculating unit calculates step input data based on the target angular position data and the existing robot condition data from a first relationship programmed therein. A reference model responds to the step input data and calculates command data from a second relationship programmed therein. The second relationship is represented by a discrete equation. The command data are used along with the existing robot condition data in controlling the robot in a manner to perform continuous path operation of the robot. The first relationship is represented by an equation derived from the discrete equation used in calculating command data for a control period after a predetermined number of control periods. In another aspect, the reference model has a response characteristic determined by a first pole group and a second pole. The first pole group is set to have the shortest possible time constant, whereas the second pole is set to have a time constant to bring the reference model close to a model having a linear response characteristic.