A zero calibration method for the lower limb joints of a humanoid robot

Abstract

The invention discloses a humanoid robot lower limb joint zero position calibration method. The humanoid robot lower limb joint zero position calibration method comprises the following steps that whether or not a fourth joint reaches a zero position is judged according to whether or not the sum Sv of the square of change rates of qx, qy and f<z> reaches a minimum value firstly, after the fourth joint reaches the corresponding zero position, the angle of a first joint is adjusted to enable the first joint to reach the corresponding zero position; and then a second joint, a sixth joint, a thirdjoint and a fifth joint are adjusted to enable the second joint, the sixth joint, the third joint and the fifth joint to reach the corresponding zero positions. Parameters qx, qy and f<z> in the calibration method are acquired through an attitude sensor mounted on a trunk and a six-dimension force / torque sensor fixed to an ankle joint correspondingly, other devices are not needed for assistance, moreover, zero position calibration is completed by the robot itself, the effects of being rapid and accurate are achieved, and the cost is saved.

Description

technical field [0001] The invention belongs to the field of calibration of humanoid robots, and in particular relates to a method for calibrating the zero position of the lower limb joints of a humanoid robot. Background technique [0002] In recent years, humanoid robots have developed rapidly, and have increasingly important application prospects in home services and national defense security. Humanoid robots use the same bipedal walking method as humans to move, and the joint position control accuracy is high. If the expected joint trajectory cannot be correctly executed, it is easy to cause the robot to lose stability during walking, or even fall. cause unnecessary damage. [0003] In the existing methods, there is a way to calibrate the zero position by using the motor end relative to the code disc and the single-turn absolute code disc at the joint end. This method will increase the electrical complexity of the robot and reduce the stability of the robot's walking; o...

AI Technical Summary

Problems solved by technology

Humanoid robots use the same bipedal walking method as humans to move, and the joint position control accuracy is high. If the expected joint trajectory cannot be correctly executed, it is easy to cause the robot to lose stability during walking, or even fall. cause unnecessary damage

[0003] In the existing methods, there is a way to calibrate the zero position by using the motor end relative to the code disc and the single-turn absolute code disc at the joint end. This method will increase the electrical complexity of the robot and reduce the stability of the robot's walking; or use the Hall element For zero calibration, it is necessary to add additional electrical components, resulting in unstable walking of the robot; or to perform joint zero calibration through mechanical limits. Generally, this method can only manually rotate the joints to the mechanical limit, and use this position as a reference Calibrate the zero position of the robot, the degree of automation is low, and the efficiency is insufficient

Images