Study on Micro-gap Flow Behavior of Electrorheological Fluid and Its Application to Haptic Display System

内质网流体是一种令人兴奋的功能流体，当施加电场时，它在几毫秒内表现出戏剧性和可逆的流变变化。在本研究中，由于仅使用电极结构，因此具有制动器，阻尼器和阀门等ER机械元件小型化的可能性，因此为了开发利用电流变流体作为触觉显示系统之一的盲文显示系统，进行了以下研究。(1)本文重点研究了压力流、旋转剪切流和振荡挤压流三种流态，作为设计内质网流体微系统的基本流场。针对两种微颗粒电流变流体和一种纳米颗粒电流变流体，通过流动可视化的方法明确了微间隙约为0.05 ~ 0.3mm时，上述三种流动形态下的微流动行为与各微流动特性之间的密切关系，并给出了适合于微间隙流动系统的电流变流体及其应用的优化设计理念。(2)采用光刻法制备了3端口微型内流阀和由两个内流阀组成的膜片微型执行器。研究了3端口微型ER阀在PID位置反馈控制下的流量控制特性和微执行器的膜片响应特性，并评估了ER膜片微执行器应用于点字显示系统的可能性。(3)采用光刻方法制作了一种具有微波纹管的ER微执行器，该微执行器可为盲文显示系统的一个引脚提供足够的行程和上推力，并对其执行性能进行了实验评估。研究发现，所研制的微致动器需要550 kPa以上的内质液供给压力，才能实现0.5 mm的行程和0.15 N的点字针上推力。安装在执行器微波纹管顶部的盲文针通过对执行器的两个ER阀采用开关控制策略来驱动。少

ER fluids are one of an exciting family of functional fluids, which show dramatic and reversible rheological changes in several milliseconds when the electric field is applied. In this research, featuring the possibility of miniaturization of ER mechanical elements such as brake, damper and valve due to their construction using only electrodes, the following investigations have been done in order to develop Braille display system utilizing electrorheological fluids as one of haptic display systems.(1) As the fundamental flow fields in designing ER fluid micro system, three flow configurations of a pressure flow, a rotational shear flow and a oscillatory squeeze flow were focused on in this research. For two kinds of micro-particle ER fluids and one kind of nano-particle ER fluid, the micro flow behaviors in the above three flow configurations with an about 0.05-0.3mm micro gap was clarified by flow visualization in close relation to each ER characteristic, and the ER fluid suitable for … More the micro gap flow system and the optimal design concept for applications were shown.(2) The 3-ports micro ER valve, and the diaphragm micro-actuator consisting of two ER valves utilizing a micro-particle ER fluid were fabricated by the photolithography method. The flow rate control characteristics for the 3-ports micro ER valve and the diaphragm response characteristics of the micro-actuator under PID position feedback control were investigated, and the possibility for the ER diaphragm micro-actuator to apply to the Braille display system was evaluated.(3) An ER micro-actuator with a micro-bellows, which performed enough stroke and push-up force for one pin of the Braille display system, was fabricated by the photolithography method and the actuating performances were evaluated experimentally. It was found that ER fluid supply pressure of more than 550 kPa was needed for the developed micro actuator to perform a stroke of 0.5 mm and a push-up force of 0.15 N of the Braille pin. The Braille pin mounted to the top of the micro-bellows of the actuator was driven by applying an on-off control strategy to two ER valves of the actuator. Less