The industrialization process of humanoid robots is accelerating, with ball screws being a core component. A ball screw typically consists of a screw, a nut, and a reversal device. Ball Screw working principle involves converting the rotary motion of the screw into the linear motion of the nut, thereby driving precise displacement movement.
The reversal device primarily serves to change direction during the motion process. In humanoid robots, a motor usually drives the ball screw to rotate, while the ball screw nut is connected to components requiring linear motion, thus driving these components to move along precise trajectories and distances
Planetary roller ball screws at the joints and miniature ball screws in dexterous hands are two important types of screw components in humanoid robots. They play roles in precise transmission, transmitting and amplifying force, and providing feedback and position control.
1) Many actions of humanoid robots require extremely high precision ball screw, such as arm extension and finger grasping. In actions requiring greater force, planetary roller ball screws can amplify the force output by the motor through rational design to meet the power demands at the joints of humanoid robots.
2) Miniature ball screws can precisely control the opening and closing of fingers, enabling the grasping of objects of different shapes and sizes. When combined with sensors, screws can provide precise position feedback information to the control system of humanoid robots, enabling precise adjustments and improving motion stability and reliability.
1) Planetary Roller Ball Screws at Joints
With the continuous promotion of humanoid robots, planetary roller ball screws are being applied more widely. Since Tesla released the humanoid robot Optimus, domestic and international industrial capital has accelerated its expansion into the humanoid robot field. For example, internationally, Samsung invested 59 billion KRW in local robot manufacturers, and Google launched RoboCat, a robot capable of self-improvement.
Domestically, companies like Xiaomi, Fourier, Unitree, Zhiyuan, and Kepler have successively launched their humanoid robot products. As one of the core components of humanoid robots, ball screws are mainly used in linear joint parts to convert the rotary motion of the motor into linear motion. Particularly, planetary roller ball screws have advantages such as high load capacity, small size, fast response, low noise, and high precision, making them highly suitable for humanoid robot motion.
The volume production of humanoid robots is expected to bring a ten-billion incremental space to the ball screw market. Based on Tesla Optimus parameters, one humanoid robot has 14 linear actuators. We make the following assumptions:
1) It is estimated that all joint parts of a humanoid robot will require planetary roller ball screws, totaling 14, potentially increasing to 16 later.
2) It is estimated that the long-term sales of humanoid robots can reach 1 million units.
3) Assuming the unit price of planetary roller ball screws decreases to 1000 yuan in the long term as the localization process accelerates. Overall, the volume production of humanoid robots will bring a ten-billion increment to the screw market.