Magnetically Driven Wireless Capsule Robot with Targeting Biopsy Function

Abstract

In this work, we present a novel magnetically actuated wireless capsule robot with biopsy function based on the principle of magnetic torsion spring (MTS). MTS is a simple device consisting of two ring-shape permanent magnets inside the capsule. It can be remotely controlled by an external uniform magnetic field so that the biopsy tool can be extended from the capsule to perform biopsy sampling operations. The energy required for biopsy is all provided by the external magnetic driving system without the need to consume the battery energy of the capsule itself. Magnetic finite element analysis is conducted to design MTS. Kinematics and force analysis of the biopsy tools is also provided. Finally, a pill-shape prototype of capsule robot is manufactured with dimension of 14 mm in diameter and 32 mm in length. In vitro experiments were carried out with this prototype to verify the feasibility of the biopsy module mechanism design and to test the ability for active locomotion.