In this paper, KUBIR 4(the name of a robot) which is a lower body of the humanoid robot applying a gravity compensator was developed. KUBIR 4 has 13 DOF, 1 DOF in waist and 12 DOF in legs. Its weight is 62kg and height is 91cm. Also, for the control for the robot, a control system developed. The control system is composed of a distributed control system where host PC is applied as a master controller and a TMS320c2408 microprocessor as a joint motor motion controller. A GUI program for easy control of robot motion was developed where payloads of each joint and joint motor’s currents are displayed in real time.
Walking experiments were performed to verify the superior performance of the robot applying the gravity compensator. For this, the gravity compensator was applied to only left knee and coxa joint to compare with right leg. Same experiments were performed on both legs and their results showed that total current consumption and the maximum load of the left leg joints were less than those of the right leg.