APPARATUS AND METHOD FOR MEASURING EXTERNAL FORCE OF DRIVING SHAFT, ROBOT JOINT HAVING THE SAME

摘要

The present invention relates to an apparatus and a method for measuring an external force applied to a drive shaft, and a robot joint having the same to prevent safety accidents from collisions when a worker and a robot work together by measuring an external force applied to the drive shaft in a stopped state of an actuator installed in the robot joint. The apparatus for measuring an external force applied to the drive shaft comprises: a first encoder, a second encoder, a rotating member, and a control device. The first encoder and the second encoder are installed on the drive shaft of the actuator to be separated from each other. The rotating member rotates the second encoder installed on a side to which the external force is applied around the drive shaft at a certain angle. The control device receives first and second pulse signals from the first and second encoders. If the drive shaft of the actuator in a stopped state experiences a torsion from the external force, the control device actuates the rotating member to rotate the second encoder around the drive shaft at a certain angle, and then measures torque from a difference between the first and second pulse signals received from the first and second encoders. The control device measures torque from the external force by subtracting compensation torque due to the rotation of the second encoder at a certain angle from the measured torque.