| Micro robot is one important research field of Micro Electro Mechanical System. Being integrated high-tech achievement, it features small inertia, high resonance frequency, short response time and etc, that makes it be applied extensively. For instance, as an international research hotspot, swimming micro robot controlled by magnetic field has potential application foreground in medical treatment.In this dissertation, by using giant magnetostrictive thin films (GMF) as actuator, a biomimetic swimming micro robot is developed. It is driven by exterior magnetic field without cable. Firstly, the magnetostrictive phenomenon and the characteristics of the giant magnetostrictive material (GMM) are introduced. As a key section the dynamic characteristics of the GMF is studied and its dynamic driving model is established, by the method of converting magnetostrictive internal stress into equivalent driving torque based on equivalent deformation of GMF and forced vibration theory. The model is significant to structural design and optimization of GMF actuator and lays a foundation to the research on biomimetic mechanism.Thereafter, on the basis of analysis on fish body structure, forces exerted on a swimming fish and propulsion mode, structure of the micro robot is confirmed and the biomimetic propulsion mechanism of the swimming micro robot is proposed. By using the GMF actuator as a caudal fin, it produces propulsion force when it is swayed under the actuation by alternating magnetic. As a result, the robot realizes its swimming motion. The propulsion model and swimming speed model is founded and calculated.Finally, experiments on dynamic characteristics of GMF and the micro robot swimming are conducted. And the error between theoretic analysis and experiment is studied. The experimental results show the micro robot features good swimming performance. Therefore a new control method on micro robot by exterior magnetic field without cable by using GMF actuator is realized.
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