Abstract: One micro in-pipe robot with giant magnetostrictive alloy actuator is developed，and a new method，without power supply cable，to drive and control the micro robot through magnetic field outside pipe is put forward．Thereby，its reliability and feasibility is improved. The control principal is that the micro robot moves forward with its legs vabrated by converting magnetic energy into mechanical one under the action of piezomagnetism and magnetomechanical couple of its micro actuator while time varied oscillating magnetic field with different frequency applied through outside pipe. Its systematical structure and operation principle are introduced．Based on vibration theory，its equations of moving speed and traction force are described by deep analysis on its moving dynamic characteristics．Robot systematical experiments to verify its feasibility are conducted．As a result，wireless drive and control method on micro robot through outside magnetic field is realized.

Key words: Dynamic characteristics, Giant magnetostriction, Micro robot