Modelling and optimisation of a five dimensional vibration isolator

A parallel mechanism with five degrees of freedom used as an active vibration isolator to isolate the vibration between devices installed on a mobile carrier is presented. The kinematic and dynamic analysis of the vibration isolator is carried out first. A wide-range magnetostrictive actuator composed of a giant magnetostrictive actuator and a microdisplacement amplification mechanism is designed for the actuation of the isolator. The magnetostrictive Terfenol-D is used as the active element of the giant magnetostrictive actuator. The microdisplacement amplification mechanism is a flexure hinge with a differential amplification principle. The transfer function from electric current to displacement is derived. The modal analysis of the parallel mechanism indicates that this parallel mechanism is suitable for active vibration isolation. The proportional-integral-derivative control method is used to adapt to the vibration environment. Finally, an optimal analysis for the entire vibration isolation system is performed and better vibration isolation effects are achieved.