Research And Application Of Micro-Actuation Based On GMM

Giant Magnetostrictive Material (GMM) is a kind of new material with highly efficiency of conversion of magnetic energy to mechanical energy. As a strategic function material, GMM is considered to be helpful to improve the overall competitive power of national high science and technology in the 21st century. With the advantages of large force, high resolution and quick response, etc, GMM has a wide and bright application prospect in the fields of ultra precision machining, microelectronics technology, biological engineering, optical fiber connection, and the manipulation and assembly of microparts, etc. Currently, Giant Magnetostrictive Actuator (GMA) based on Joule effect of GMM, becomes research focus in the field of precision actuation. Although many achievements have been made, research on GMA is at the experimental stage and many problems still exist, especially about the GMM thermal error and nonlinear output, which greatly influenced its application. Aimed at current problems of GMA, research on overall optimum design, performance analysis, modelling and controlling of hysteresis, application of micro-actuation, etc, were carried out in the dissertation.Definition, principle and classification of modern micro actuation were systemically stated from the view of precision engineering and ultra precision engineering. The development course and characteristic of GMM were introduced, its performance and advantages were discussed, and the state of its application to micro actuatiion was presented. On the basis of Ferromagnetics, the origin of magnetism, the magnetostrictive process and the generation of hysteresis were explained.GMA structure design includes magnetic design and thermal design, and they are relevant. However, current researches are focused on single magnetic design or single thermal design. Based on characterics of GMM, the overall optimum design of GMA was proposed. Based on meeting the requirements of magnetic design, the influence of thermal deformation was systematically analyzed. Then a temperature controlling structure with two water-cooling cavums was proposed. Both simulation and experiments indicate the GMA proposed performs well with high precision and stabiltiy.Linear dynamic model of GMA system including constant current power was established on current controlling model. For the characteristic of large-time delay of GMA system, the PID controller with Smith compensator and fuzzy PID controller with Smith compensator were designed, respectively, and they were analysed and compared with Matlab. Simulation shows Fuzzy PID controller with Smith compensator can meet the demands of quick response of GMA system.The measuring and controlling system for GMA was established. In the stable environment, GMA pre-pressure experiment, biased current experiment, hysteresis performance experiment and precision positioning experiment were carried out, and the biased conditions and work scope were determined according to the experiments. Major hysteresis hoop and 19 first order reversal curves were measured and analyzed exactly. On the basis of experiment results, Preisach hysteresis modified model of GMA was presented. In order to avoid inverting the Preisach operators, a current position-based input modified iterated algorithm was proposed.Application is the objective, direction and restriction of the micro-actuation technology research. Several feasible application forms of GMA were discussed. Three devices for application of GMA were proposed. Their structures were designed, and their performance and application occasions were analyzed.