Motion planning for continuum reconfigurable incisionless surgical parallel robots

Abstract

Continuum Reconfigurable Incisionless Surgical Parallel (CRISP) robots consist of multiple needle-diameter flexible instruments that are assembled into a parallel structure inside the human body. With a camera placed at the tip of one of the instruments, the CRISP robot can be used to inspect anatomical sites in constrained body cavities in a minimally invasive manner. We introduce a motion planner for CRISP robots that computes manipulations of the flexible instruments outside the body such that the camera can visually inspect a user-specified site of clinical interest inside the body. Our sampling-based motion planner ensures avoidance of collisions with anatomical obstacles inside the body, enforces remote-center-of-motion constraints on the instrument's entry points into the body, and efficiently handles the expensive computation of CRISP robot kinematics. We also extend the motion planner to estimate the set of points inside a body cavity that can be visually inspected by the camera of a CRISP robot for a given setup. We demonstrate our method in a simulated endoscopic medical procedure in the pleural space around a lung.