Improving resolution of robotic capsule locomotion using dynamic electromagnetic field.

Abstract

This paper describes a new method to control the motion of swallowable wireless capsule endoscopy devices. A dynamic magnetic field produced by a set of external magnetic coils is used to manage the locomotion of the capsule. A permanent magnet is embedded into the capsule in order to manipulate the capsule by changing the external magnetic field strength for each specific position. The dynamic magnetic field is externally controlled to reach and maintain the equilibrium state for holding the capsule in a specific location. This is achieved by keeping the net force of magnetic fields zero. To start the mobility, the magnetic field from one of the external field sources will be reduced for a certain amount of time by sending an OFF-pulse (a current source). The required forces and the pulses are controlled by a specific algorithm to control the step size of the movement in order to achieve precise motion at any chosen velocity. The proposed method is designed to provide a precise motion control with a system extremely low in complexity.