Kinematics Modeling and Error Compensation for Miniaturized Puncture Surgical Robot

Percutaneous needle biopsy serves as the gold standard for oncological diagnosis. However, in clinical practice, it faces challenges such as high operation volumes and suboptimal precision resulting from the variability of manual operations. Although conventional robotic systems can alleviate this problem to some extent, they are plagued by large footprints and high costs, which restricts their widespread application. This paper presents a miniaturized 4-DOF parallel puncture robot to fill these gaps. Regarding the proposed robot, its kinematic framework is elaborated, involving six coordinate systems and transformation matrices. The kinematics of the lower and upper platforms are described in detail, and the pose of the puncture needle is solved. The Jacobian matrix is derived for motion analysis and inverse kinematics. To tackle inaccurate kinematic parameters, an iterative weighted least squares calibration method is devised. Experimental results reveal that this calibration method effectively decreases navigation errors for both base related and end-effector related points, demonstrating its efficacy in improving the robot’s performance.