Thermoelectric Cooling Application to Motors for High-Power Operation

Joint motors of legged robots and manipulators need to withstand temporary high loads during walking, posture maintenance, and contact with external objects. To only increase the torque, the gear ratio can be increased; however, this decelerates the movement. To increase the power of the motor, improving the torque–current characteristics or applying a high current is necessary. When a high current is applied, a large amount of heat is generated by the motor, which can cause motor failure. In this study, we used thermoelectric cooling as a new cooling method for robot joint motors and verified its effectiveness. We developed a thermoelectric cooling module that can significantly cool a motor before it experiences a high current. Experiments were conducted in which a motor was subjected to a high-load motion, and the results with and without the thermoelectric cooling module were compared. It was shown that the developed thermoelectric cooling system improved the performance of the motor.