A new method to drive and control micro in-pipe robot by means of magnetic field outside pipe is put forward,in which wireless micro robot can move forward driven by the vibration of its legs through converting magnetic energy into mechanical one under the action of piezomagnetism and magnetomechanical coupling of its micro GMA,when time varied oscillating magnetic field with different frequency applied outside pipe.Firstly its systematical structure and operation principle are introduced,and energy converting process from outside magnetic one into mechanical one is analyzed through setting up the magnetic and mechanical dynamic model of GMA and establishing dynamic model of two stage amplifier of mobile carrier.Robot systematical experiments show the correctness of the theoretical analysis and its feasibility.As a result,drive and control method without cable through outside magnetic field is realized.
A drive and control method is put forward for a variable diameter capsule micro robot to screw forward in intestine using magnetic coupling between an inner actuator inside the robot and the rotational magnetic field generated by a rotating outer actuator. The structures of the outer and inner actuators are magnet cylinders with multiple magnetic poles in tegular shape alternating with dissimilar radial magnetization. An universal mathematical model of magnetic torque at eccentric state is established based on the equivalent magnetic charge method, and the characteristics of magnetic torque with respect to structural parameters of actuators are theoretically studied. Experiments show that the driving method features advantages such as powerful magnetic torque, high safety, reliability, etc. The driving ability of the variable diameter capsule micro robot is greatly improved by its automatic radial clearance compensation. The magnetic drive system has a promising prospect of medical applications in intestine.
