Development of active six-degrees-of-freedom micro-vibration control system using hybridactuators comprising air actuators and giant magnetostrictive actuators

Abstract

In recent years, there has been an increasing demand for micro-vibration free space fromindustrial and scientific organizations. In response to this demand, several activemicro-vibration control systems utilizing various types of actuators have been developedand applied in various environments and to a number of machines. The authors havedeveloped an active micro-vibration control system with six degrees of freedom using giantmagnetostrictive (GMS) actuators and actually have applied it to an FIB (focused ionbeam).In general, a GMS actuator has a quicker response time and bigger displacementcharacteristics at higher frequencies than an air actuator. Therefore, we have developed ahybrid actuator that consists of a GMS actuator and an air actuator. Its main feature isthat the two actuators are arranged in parallel. Ideally, such a hybrid actuatorwould have the merits of both component systems. Through experimental testson the hybrid actuator and simulation analysis on the uni-axial micro-vibrationcontrol device using the hybrid actuator, we have shown that this is the case.Following this successful result, we have developed an active 6-DOF micro-vibration controlsystem using hybrid actuators. This paper presents an outline of the active 6-DOFmicro-vibration control system, the hybrid actuator used, and the design strategy of thecontrol system. Results of control experiments under various disturbances are described.Through these results, it is verified that an active 6-DOF micro-vibration control systemusing hybrid actuators controls vibration more effectively than use of air actuatorsalone. This good performance is realized by the efficiency of the hybrid actuator,which is attributed to the collaboration of the air actuator and GMS actuators.