METHOD AND APPARATUS FOR CONTROLLING A ROBOT

A method for controlling a multi-joint robot having redundant operating joints, wherein joint velocities are calculated for non-redundant joints with redundant joints being fixed for each of at least a portion of the combinations of the non-redundant joints excluding redundant joints capable of attaining the movement of the robot end at a command velocity specified to the robot, by inverse-coordinate-transformation from the spatial coordinate to a joint coordinate inherent to the robot, on the basis of joint angles detected by an encoder mounted on the joints of the robot and the joint velocities are averaged or nearly averaged to obtain the average value or nearly average value as a desired joint velocity for the joints. The desired joint velocity is supplied to a velocity control unit of the robot as a controlled variable.