Method and system for correcting pose error at end of manipulator based on ellipse feature

Abstract

The invention relates to a mechanical arm tail-end pose error correction method based on elliptic characteristics. The method comprises the steps of obtaining an image of a round-mouth target tank, extracting a target ellipse from the image, determining the relative position and axial relation between a tank mouth of the round-mouth target tank and an actuator according to the elliptic characteristics of the target ellipse, determining a current pose of the actuator, joint angles of all joints of a mechanical arm and the pose deviation value of the actuator according to the relative positions,the axial relation and configuration constraint of the mechanical arm, and adjusting the mechanical arm according to the pose deviation value till the pose deviation value of the actuator is smallerthan a preset value. By means of the method, the problems that single elliptic characteristic positioning has ambiguity and axial rotation poses cannot be determined are solved, accurate guidance canbe provided for the mechanical arm to collect samples and put the samples into the target tank, and control errors caused by local flexibility or joint clearance are corrected. The invention further provides a mechanical arm tail-end pose error correction system based on the elliptic characteristics.

Description

technical field [0001] The invention relates to the technical field of manipulator control, in particular to a method and system for correcting a pose error at the end of a manipulator based on an ellipse feature. Background technique [0002] With the development of science and technology, the mechanical arm is not only more and more widely used on the ground, but also plays an increasingly important role in the landing detection of the surface of extraterrestrial celestial bodies, especially for the sampling operation of the surface of extraterrestrial celestial bodies. . [0003] Landing sampling and return on the surface of extraterrestrial celestial bodies is an important means for the world's aerospace powers to explore deep space and expand human understanding of alien planets and the solar system. The robotic arm is an essential key equipment for landing sampling tasks on the surface of extraterrestrial celestial bodies. It can independently perform sampling tasks a...

AI Technical Summary

Problems solved by technology

However, in the prior art, image features are usually selected to solve the relative position between the target and the end effector of the manipulator, and the manipulator is controlled according to the position deviation, but this method requires the selection of image features that can uniquely represent the position state of the target , and this method only focuses on the position or pose deviation of the end of the manipulator, and cannot achieve precise control of the joint angle deviation of the manipulator

Images