磁流变减振驱动器的响应时间试验与分析

本文首先通过分析平行平板间磁流变液流变后的非稳态过程，建立了磁流变减振驱动器响应时间的计算理论。分析表明，磁流变减振驱动器响应时间的主要影响因素是流体的动力粘度和活塞与缸体的间隙，而与流变液的剪切屈服强度和活塞两端的压差无关，利用此理论初步估计的磁流变减振驱动器的响应时间为毫秒级。其次，通过瞬间改变输入电流，进行了磁流变减振驱动器阻尼力响应时间试验。试验结果表明，磁流变减振驱动器的响应时间为百毫秒级，远远大于理论值。最后，计算分析表明，液体气泡的存在延缓了减振驱动器的响应时间。

Response time experiment and analysis of magnetorheological fluid actuator

In this paper, firstly, by analyzing the unstable state of the magnetorheological(MR) fluid that between parallel plates after rheologic, the calculation theory of response time of damping force for MR fluid actuator is built. The theory shows that the main influencing factors of response time of MR fluid actuator are the dynamic viscosity of MR fluid and the gap between piston and cylinder, the shearing field of MR fluid and the pressure difference between both ends of the piston do not influence the response time. By the theory, the response time of MR fluid actuator is estimated to be about millisecond. Secondly, by quickly changing input electric current from one level to another, the response time experiments of damping force for MR fluid actuator are done, and the results shows that the response time is about hundreds of millisecond, more bigger than the theory results. Finally, analyzing with the theory shows that it is the air bubbles in the fluid that delay the response time of MR fluid actuator.