Electrostatic actuator with liquid metal–elastomer compliant electrodes used for on-chip microvalving (original) (raw)
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Journal of Micromechanics and Microengineering, 2020
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IEEE/ASME Journal of Microelectromechanical Systems, 1996
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Proceedings of the IEEE International Conference on Micro Electro Mechanical Systems (MEMS), 2008
We report measurements of displacement and mechanical work for miniaturized Dielectric Elastomer Actuators (DEAs) whose compliant electrodes were fabricated using metal ion implantation. 20 to 30 µm thick Polydimethylsiloxane (PDMS) membranes were bonded to silicon chips with through holes of diameter 2 to 3 mm and were implanted on both sides with gold ions. Out-of-plane deflection recorded as a function of voltage and applied mechanical distributed load was in very good agreement with an analytical model. Unloaded vertical displacements up to 7% of the membrane's diameter were recorded and mechanical work up to 0.3 µJ was obtained with an applied pressure of 1 kPa. This performance data and associated model allow such miniaturized polymer actuators to be efficiently dimensioned for different applications, for instance in micropumps and active optical devices.
Fabrication of micro electro-rheological valves (ER valves) by micromachining and experiments
Sensors and Actuators A: …, 2002
As an advanced control component for practical micromachines using¯uid power in millimeter size, the authors have proposed and developed a microvalve using homogeneous electro-rheological (ER)¯uids called micro ER valve and veri®ed the validity through basic experiments using several micro ER valves fabricated by conventional machining. In this paper, further miniaturized ER valves are realized by using micromachining technologies. Firstly, to investigate an ER effect in micro size, several two-port micro ER valves with different electrode gap lengths are fabricated and tested. It is ascertained that the static viscosity change rate is 4.5 constant with miniaturization. Secondly, a threeport micro ER valve is fabricated and the static and dynamic characteristics are experimentally investigated. It is ascertained that the controllable pressure change rate is 60% of supply pressure and the response time T r de®ned in this study is 0.2 s. Finally, the validity of the micro ER valve is con®rmed by applying to position control of a bellows microactuator. #