Development of a uni-axial hybrid actuator using the combination of an air actuator and a giant-magnetostrictiveactuator

Abstract

Active microvibration control systems have beendeveloped and applied in a practical manner. Various types ofactuator, for example an air actuator, a linear movingactuator, a piezoelectric (PZT) actuator and a giant-magnetostrictive (GMS)actuator, have been used. In general, all actuators have bothmerits and demerits, so an optimal actuator should be selected based on the objective performance and the conditions of usage.We developed an active 6-DOF microvibration control systemusing GMS actuators. It has been speculatedthat the GMS actuator is suitable as adisplacement actuator for an active microvibration control. Thereasons for this are that it has better durability andreliability compared with a PZT actuator, and alsoits response to an input signal is much faster than an airactuator. However, the demerits of the GMSactuator come to light through practical application of thesystem. The displacement property tends to decrease with increase in the magnitude of forced axial load, and it cannot generate a sufficient displacement in a low frequency range.Therefore, in order to improve the above-mentioned demeritsrelated to a GMS actuator and an airactuator, we have developed a new type of hybrid actuator usinga GMS actuator and an air actuator. The twoactuators are arranged in parallel. This structural featureenables the new hybrid actuator to make up for both of the singleactuators' demerits. Consequently, it has become possible tocontrol displacement in the wider frequency range of0.1-100 Hz and to generate a maximum displacement of more than1 mm.This paper presents an outline of the experimental new hybrid actuator, the result of a dynamic characteristic test of theactuator and simulation analysis on the uni-axialmicrovibration control device using the hybrid actuator.Through these results, the higher performance achieved by the newly developed hybrid actuator isverified.