Abstract: A non-contact drive and control method on capsule type micro robot is actuated by extended rotation magnetic field proposed, in which exterior permanent magnet driver is composed of multiple magnetic poles magnetized in radial direction, and interior permanent magnet driver built in the robot is in the same structure as exterior one. On the action of magneto mechanical coupling of rotating magnetic field generated by turning of exterior driver, the robot is spun forward in intestine by propulsion in axial direction generated by the function of fluid dynamic pressure distributed on spiral surface of the robot. Firstly the structure of capsule micro robot system is introduced, then a kinematics mathematical model of capsule micro robot in pipeline environment is established on the basis of Renault and Navier-Stokes equation. Finally theoretical and experimental researches on the relationship between its spiral parameters and swimming speed are carried out, resulting in the discovery of critical gap phenomenon. With big drive torque, this kind of robot is suitable for swimming inside an enclosed pipe full of high viscosity liquid, and it has good prospect of application inside human intestine and blood vessel.

Key words: Capsule micro robot, Kinematics characteristics, Rotation magnetic field, Spiral parameters