Design of a High-torque Robot Joint and Its Control System

Abstract The robot joint is one of the key components of robots. With the wide application of robot joints, the demand for joint torque is becoming higher and higher. However, at present, most high-torque robot joints are generally large in weight and size, which creates problems for some applications. For this purpose, a high-torque and high-torque-density robot joint is proposed. To improve the joints’ torque density, the lightweight motor and reducer with a large reduction ratio are selected, and the mechanical structure design is based on weight reduction, miniaturization, and heat dissipation. The maximum torque of the proposed robot joint can reach up to 182Nm, and its mass is only 1.8kg. Besides, an embedded control system is designed to control the robot joint. Many experiments were conducted to measure the robot joint’s characteristics, such as torque, speed, and control features. And the designed robot joints are successfully applied to a biped robot. The results verify the performance of the designed robot joint and its control system.