Abstract: Design and control method to a novel precision and large stroke actuator driven by solid-state smart material are realized. With the combination of coarse and fine drive mechanism, a combined large stroke giant magnetostrictive actuator is constructed. Main researches concerning the design of the novel actuator, the control system and experimental method based upon the actuator prototype are introduced. Control and transfer-function model by taking consideration of the combined excitation of electromagnetic field and permanent-magnet biased field is established; meanwhile, a coarse-fine precision control scheme is implemented. The experimental results prove both the capacity of long stroke and positioning accuracy of the actuator and the effectiveness of the control system with the control method. The output stroke may reach up to 0.71 mm. To limit the heat expansion effect, the running stroke is set up to 0.6 mm. The precision of each using giant magnetostrictive actuator may reach ±30 nm, and the precision of the combined giant magnetostrictive actuator may reach up to ±90 nm. The mechanism and control method in current work may be generally used in solid-state smart-material drive actuator for realizing large-stroke and high precision positioning.

Key words: Combined actuator, Fed forward control, Flexible hinge amplify mechanism, Giant magnetostrictive actuator, Long-stroke actuator