Screw-Based Motion Planning for Bevel-Tip Flexible Needles in 3D Environments with Obstacles

Area of Science:

• Robotics
• Medical Device Engineering
• Computational Geometry

Background:

• Bevel-tip flexible needles offer enhanced mobility over rigid needles for accessing difficult targets.
• Accurate motion planning for these steerable needles is challenging due to nonholonomic constraints and inverse kinematics.

Purpose of the Study:

• To develop a 3D motion planning approach for bevel-tip needles in environments with obstacles.
• To overcome limitations of configuration space discretization by discretizing control space for analytical trajectory expression.

Main Methods:

• Discretization of the control space for analytical needle trajectory generation.
• Development of a fast optimization routine for pathfinding in 3D obstacle environments.
• Introduction of two distinct discretization strategies for varied path structures.

Main Results:

• The proposed method achieves rapid, locally optimal path planning for bevel-tip needles in cluttered 3D spaces.
• Computation time is reduced to a few seconds on a standard PC, eliminating the need for numerical simulations.
• Both introduced discretization strategies successfully generated valid start-to-goal trajectories.

Conclusions:

• This work presents the first known method for 3D motion planning of bevel-tip needles in obstacle-rich environments.
• The control space discretization approach offers an efficient and effective solution for steerable needle motion planning.
• The method has significant implications for improving precision and safety in minimally invasive procedures.