Mechanical arm hand-eye calibration method based on spatial distance and epipolar line constraint

Abstract

The invention discloses a mechanical arm hand-eye calibration method based on the spatial distance and epipolar line constraint. The mechanical arm hand-eye calibration method comprises the steps thatan initial value of a hand-eye conversion matrix is solved, a conversion relationship of a camera fixed to a mechanical arm when the mechanical arm is at the two different positions is obtained, epipolar line errors of feature points in images are calculated through internal parameters of the camera, the feature points are subjected to three-dimensional reconstruction, the spatial distance between the reconstructed feature points is calculated, spatial distance errors are calculated according to the actual spatial distance, the cumulative sum of all the epipolar line errors and the spatial distance errors of all the feature points serve as an optimized objective function, iterative optimization is conducted through a Levenberg-Marquardt algorithm, and the hand-eye conversion matrix with higher precision is obtained. According to the mechanical arm hand-eye calibration method, the optimized objective function which better meets the actual demands can be constructed, thus the spatial size calculated by the hand-eye conversion matrix is more consistent to the actual size, the convergence rate of iterative optimization is increased, it is ensured that the optimized parameters meet theepipolar geometry constraint, and the precision is higher.

Description

technical field [0001] The present invention relates to a visual calibration method, relates to a mechanical arm hand-eye calibration method based on spatial distance and epipolar constraints, is suitable for a robot visual guidance system for fusion of a mechanical arm and a camera, and relates to visual assembly of a mechanical arm and assisted surgery with a mechanical arm And technical fields such as robotic arm visual inspection. Background technique [0002] The vision-guided manipulator control system based on the fusion of camera and manipulator can improve the flexibility, automation and intelligence of production. increasingly important role. The camera fixed on the end effector of the manipulator can be used to complete the target detection task, and most of the detection results are in the camera coordinate system. Therefore, it is necessary to obtain a high-precision hand-eye transformation matrix, so that the detection results are converted from the camera co...

AI Technical Summary

Problems solved by technology

At present, the existing hand-eye calibration algorithm lacks the constraint information at the actual 3D level, and does not integrate the spatial dimension information and the constraint information that the spatial projection geometry should satisfy into the process of parameter optimization.

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