cs.ROMar 16, 2026

Surgical Robot, Path Planning, Joint Space, Riemannian Manifolds

Authors: Yoshiki Yamamoto, Maina Sogabe, Shunichi Hirahara, Toshiki Kaisaki, Tetsuro Miyazaki, Kenji Kawashima

Organizations: The University of Tokyo, Department of Information Physics and Computing, Tokyo, 113-8656, Japan · The University of Tokyo, Department of Precision Engineering, Tokyo, 113-8656, Japan · National Institute of Informatics, Principles of Informatics Research Division, Tokyo, 101-8430, Japan

Abstract

Robotic surgery for minimally invasive surgery can reduce the surgeon's workload by autonomously guiding robotic forceps. Movement of the robot is restricted around a fixed insertion port. The robot often encounters angle limitations during operation. Also, the surface of the abdominal cavity is non-concave, making it computationally expensive to find the desired path.In this work, to solve these problems, we propose a method for path planning in joint space by transforming the position into a Riemannian manifold. An edge cost function is defined to search for a desired path in the joint space and reduce the range of motion of the joints. We found that the organ is mostly non-concave, making it easy to find the optimal path using gradient descent method. Experimental results demonstrated that the proposed method reduces the range of joint angle movement compared to calculations in position space.

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