Path planning for flexible needle based on both insertion mechanism kinematics and needle bending model

Area of Science:

• Robotics
• Medical Engineering
• Surgical Technology

Background:

• Limited space in Magnetic Resonance (MR) environments complicates robotic insertion.
• Coupled motion in insertion mechanisms reduces robot flexibility and challenges path planning.
• Flexible needle bending rules necessitate a dedicated bending model for accurate path planning.

Purpose of the Study:

• To develop a path planner for flexible needles in robotic surgery.
• To address challenges posed by coupled motion and needle bending in confined MR environments.
• To enhance the accuracy and flexibility of robotic insertion mechanisms.

Main Methods:

• Performed kinematic analysis of coupled motion in the insertion robot.
• Established a bending model for the flexible needle based on needle-tissue interactions.
• Integrated coupled motion kinematics and needle bending model for path planning using inverse kinematics.

Main Results:

• Insertion experiments demonstrated high accuracy with root mean square errors of 0.83 mm and 0.74 mm.
• Maximum errors of 1.1 mm and 0.9 mm were recorded for different targets.
• The path planning algorithm proved effective and accurate, meeting general minimally invasive surgery requirements.

Conclusions:

• The proposed path planner offers a new solution for robotic insertion in minimally invasive surgery.
• The method enables insertion mechanisms to operate effectively within confined MR environments.
• This approach holds significant potential for future clinical applications in medicine.