Magnetostrictive Mirror Precision Micro-displacement Deflection Drive Mechanism Design

With the development of precision and ultra-precision equipment in the field of national defense technology,precision manufacturing and other fields,mirror deflection devices have been widely used,such as a beam deflection device for high speed and low voltage excitation applied to national defense science,high speed scanner and astronomical telescope mirror drive.However,these mirror deflection devices have the disadvantages of slow speed,high voltage,large volume,short life and low deflection accuracy.In order to improve these defects,it is necessary to seek a precise deflection technology of mirror.Therefore,taking full advantage of the excellent performance of Giant Magnetostrictive Material(GMM),a magnetostrictive mirror precision micro-displacement deflection drive mechanism is designed.The main research work includes the following points:Firstly,the microscopic mechanism of GMM and the microstructure of GMM are studied.Based on this principle,the mechanism of GMM positve effects and the GMM properties are studied,and the cause of the mechanism of GMM positve and negative effects are analyzed,and finally the characteristics of GMM are clarified.Based on the excellent features of GMM,a magnetostrictive mirror precision micro-displacement deflection drive mechanism is designed,and the Giant Magnetostrictive Actuator(GMA)and the mirror deflection device involved in the whole mechanism are also designed in detail.Firstly,based on the mechanism of GMM positive effects and excellent characteristics,a giant magnetostrictive actuator is designed based on GMM rod as the core component.The magnetic circuit and magnetic field are studied by COMSOL software.Then the structure of mirror deflection device is designed,and the cantilever beam of the mirror deflection device is analyzed by finite element software.According to the mechanism of magnetostrictive effect and the result of finite element analysis,the design of magnetostrictive mirror precision micro-displacement deflection drive mechanism is finally completed.Based on the mechanism of GMM positive effect and the theory of internal energy in GMM,the relationship between output displacement and force and magnetization is established.Based on these thoeries,the relation model of the output displacement of the GMM rod and the deflection displacement of mirror is deduced.Finally,based on the designed GMA and mirror deflection device,an experimental platform of magnetostrictive mirror precision micro-displacement deflection drive mechanism is set up to study the relationship between the pre-pressure of GMA and the direct current excitation on the deflection displacement of mirror and the output displacement of GMA,and mirror deflection displacement and GMA output displacement of the dynamic displacement output characteristics is studied under the condition of alternating current.The experimental results show that when the GMA pre-tension is 16 MPa,the the mirror deflection displacement and the output displacement of the GMA reache the peak value;the mirror deflection displacement and the output displacement of the GMA are not completely linear with the current and have certain hysteresis characteristics.The output displacement of GMA can be effectively amplified by the cantilever beam of the device via many experiments.The linear range of the mirror deflection displacement is in the range of 0.5A to 1.5A;under the alternating current excitation of 3A,the optimum frequency of the mirror deflection displacement is 500 Hz.