A Novel Magnetic Anchored and Steered Camera Robot for Single Port Access Surgery

Abstract

This paper presents a novel magnetic anchored and steered camera robot intended for minimally invasive surgery (MIS), particularly for single port access (SPA) surgery. The design aims to achieve both compactness and a planar pan/tilt workspace (instead of hemispheric) to lower robot footprint in vertical space. Robot comprises two 6mm×6mm diametrically magnetized internal permanent magnets (IPMs) fixed at either ends of a small cylindrical capsule, with camera module and a 45°mirror capped inside capsule. As such, camera view orientation can be steered in 2-DOF across range of 180° tilt and 360° panning, all within a planar workspace close to surface of anchor. Using only two small IPMs for all necessary functions (anchoring, translation along intra-abdominal surface, and steering) reduces bulk and length of robot. The robot is investigated first by finite element methods. Theoretical models for both tilting and panning were then built based on FEM results. The models are evaluated and verified by checking its predictions in benchtop experiments. Ex vivo evaluations was also utilized to prove feasibility of device in environment similar to human anatomy. Overall, the camera robot prototype is compact (4cm length; 7mm diameter), lightweight (3.6g), motor-free, and allow view orientation control (tilting and panning) in a planar workspace. Minimal footprint in vertical space is ideal for many MIS applications, where vertical space is extremely limited.