超磁致伸缩电静液作动器的试验研究与特性分析

超磁致伸缩材料驱动的电静液作动器具有结构高度集成、性能影响因素多以及理论分析复杂等特点，为寻求超磁致伸缩电静液作动器可靠的理论分析方法以提高其输出性能，首先搭建了超磁致伸缩执行器与作动器试验测试平台，完成了执行器与作动器动态特性对比试验，在准确测试与观察试验现象的基础上，对超磁致伸缩电静液作动器进行结构分解，以各环节固有频率为理论分析切入点，采用试验、理论与有限元分析相结合的方法，分析了悬臂梁阀片、管路、液压缸以及蓄能器等动态特性对作动器输出性能的影响规律，总结出符合试验结果的理论分析方法并确定了影响与制约作动器输出性能的关键环节，最后提出了超磁致伸缩电静液作动器优化改进方案，优化后作动器试验结果显示：在200 Hz左右、0.6 MPa 的偏压作用下，选取 0.15 mm 厚度的阀片，作动器的输出性能达到最佳，其输出流量最大可达1.2 L/min。

Experimental investigation and characteristic analysis of a giant magnetostrictive materials-based electro-hydrostatic actuator

Electro-hydrostatic actuators (EHAs) driven by giant magnetostrictive materials (GMM) have some features including highly integrated structure,lots of factors affecting the performance and complex theoretical analysis. In order to search a reliable theoretical analysis method of giant magnetostrictive materials-based electro-hydrostatic actuator (GMEHA) and improving the output performance, the experiment platform of GMA is built in this paper and contrast experiment of actuator dynamic characteristics is completed. On the basis of accurate test and observation of experimental phenomena,structure decomposition of GMEHA is done. Natural frequency of each part is set as breakthrough point of theoretical analysis. A method of combining experiments,theory and finite element analysis (FEA) is taken to analyze the effect on the output performance of actuator caused by dynamic characteristics of cantilever valve,pipeline,hydraulic cylinder and accumulator. The theory analysis method in accordance with experiment is concluded and the key part which affected and restricted the output performance of actuator is determined. Finally, the optimization scheme of GMEHA is put forward on the basis of the above theoretical and experimental researches. Experimental results of actuator after optimization show that the best output performance has been received at the frequency of about 200 Hz and the bias of 0.6 MPa with the valve of 0.15 mm thickness,and the maximum output flow can reach 1.2 L/min.