中文摘要：

针对超磁致伸缩致动器输出位移有限,无法直接驱动伺服阀阀芯运动的问题,设计了一种基于柔性活塞的新型液压式微位移放大机构：由超磁致伸缩（GMM）棒驱动大活塞变形,并通过密闭容腔内的油液在小活塞端将GMM棒的输出位移放大.建立了超磁致伸缩致动器及其液压式微位移放大机构的耦合模型,采用弹性小挠度理论,有限元法和液压弹簧刚度理论对放大机构进行了分析和优化,并制作了样机.仿真和实验表明,所设计的液压式微位移放大机构可将GMM棒位移放大3.2倍,所建立的耦合模型较准确,误差在10％以内.

英文摘要：

Limited by the output displacement, the Giant Magnetostrictive Actuator （GMA） cannot drive the spool directly. A hydraulic displacement amplifier based on flexible piston is designed; the flexible piston is pushed by the deformation of Giant Magnetostrictive Material （GMM）, and finally pushed the small piston with much larger output. The coupled model of hydraulically amplified GMA is established; the structure is analyzed based on elastic small deformation theory and finite element method （FEM） ; and through simulation and test of a prototype, the output displacement is amplified 3.2 times by hydraulic amplifier. The proposed model is valid with an error beneath 10%.