Robot-assisted puncture operation end tool center calibration method based on stereoscopic vision

Abstract

The invention discloses a robot-assisted puncture operation end tool center calibration method based on stereoscopic vision, which belongs to the field of robot control, and aims to realize accurate control of a robot on a needle tip. The method comprises the following steps: performing monocular vision calibration on two cameras, performing binocular system vision calibration, and establishing avision measurement space coordinate system; wherein a puncture needle performs single translational motion and rotary translational motion respectively in a visual measurement space range; processingan image acquired in the moving operation to generate a closed area and a minimum enclosing rectangle of the closed area; circularly detecting an intersection point of the short edge of the minimum enclosing rectangle and the closed area, and obtaining the position change description of a needle tip in the visual measurement space coordinate system in the single translational motion process and the position change description of the needle tip in the visual measurement space coordinate system in the rotary translational motion process; obtaining an attitude rotation relationship between the visual measurement space coordinate system and a robot base coordinate system; obtaining position description of the needle tip relative to the tail end of the mechanical arm, and completing position calibration of the needle tip.

Description

technical field [0001] The invention belongs to the field of robot control and relates to a needle point position calibration technology. Background technique [0002] Percutaneous puncture surgery is widely used in the fields of trigeminal nerve thermal coagulation, radiofrequency ablation, brachytherapy and tumor biopsy. However, due to the nonlinearity and non-rigidity of human tissue, it is extremely difficult to achieve precise puncture by hand. Development, robot-assisted percutaneous puncture surgery provides a technical solution for the realization of precise puncture, an essential technology in robot-assisted percutaneous puncture surgery is the needle tip (that is, the center of the end tool during robot-assisted puncture surgery) Calibrate to achieve precise control of the needle tip by the robot to achieve precise puncture. [0003] At present, most of the typical end-tool center calibration methods are contact-based, which will inevitably introduce large errors...

AI Technical Summary

Problems solved by technology

[0003] At present, most of the typical end-tool center calibration methods are contact-based, which will inevitably introduce large errors in the calibration process for low-rigidity end-effector tools such as puncture needles. Of course, some technologies are non-contact. The main principle It is the characteristic of the end tool obtained by the line laser. Currently, it is only suitable for large and simple end tools such as welding guns, and it is difficult to apply to small targets such as puncture needles.

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