Coordinate labeling method for mechanical arm

Abstract

The invention relates to a coordinate labeling method for a mechanical arm. The coordinate labeling method for the mechanical arm comprises the following steps that, a shaft arm moves towards the position of a camera till an original label is clear and visible in the shot view range of the camera, a visual system software records and treats the coordinate of the original label captured by the camera as a first coordinate; the shaft arm keeps the position unchangeable, after a end head rotates by a certain angle, the visual system software records and treats the coordinate of the original label captured by the camera as a second coordinate; after the end head rotates by a certain angle, the coordinate of the original label captured by the camera is recorded and treated as a third coordinate; and first circle centers of circles where the first coordinate, the second coordinate and the third coordinate are located are calculated, and a center coordinate A is obtained. Sampling and calculating in the measurement process are completed automatically, human eye aligning is not needed, the happening probability of random errors is reduced, the overlapping operation is conducted under a view where an image photographed by the camera is magnified for times, the accuracy is hundreds times of human eye aligning, the operation is simple, rapid and convenient, and the applicability and flexibility are high.

Description

technical field [0001] The invention relates to the technical field of robots, in particular to a coordinate calibration method of a mechanical arm. Background technique [0002] The basis of the precise movement of the robotic arm is the accurate establishment of the coordinate system. After the correct correspondence between the mechanical coordinate system and the visual coordinate system is established, it can accurately move to the corresponding position according to the coordinate parameters given by the controller. Therefore, the coordinates of the robotic arm need to be calibrated before it is put into use, and the robotic arm after a period of operation also needs to be recalibrated regularly to ensure operating accuracy. [0003] There are two traditional methods for calibrating robotic arms: [0004] 1. Use conical tools: the first conical tool is installed on the third axis of the mechanical arm, and the second conical tool is fixed under the third axis of the m...

AI Technical Summary

Problems solved by technology

This installation method cannot ensure that the center of the conical tool is on the same line as the center of the rotation axis of the robot arm, resulting in a certain deviation

The second is the alignment process of the cone tips of the two conical tools. This alignment process depends on the human eye determination of the operator. The accuracy of human eye recognition can only reach about 0.1mm at most, so the center of the rotation axis determined by the tool The accuracy of the coordinates can only reach 0.1mm, which cannot meet the accuracy requirements of the actual application for the robotic arm

But there are still some inherent errors

First of all, when making the circular hole array, it is necessary to strictly ensure that the distance between the center of the circle is equal, so the manufacturing accuracy of the mold will directly affect the coordinate accuracy of the robot arm

Secondly, the diameter of the round hole of the round hole array mold is larger than the diameter of the cylinder. During the insertion process, there is still a gap, so the center of the round hole cannot be completely coincided with the center of the cylinder.

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