Electropermanent magnet based wireless microactuator for microfluidic systems: Actuator control and energy consumption aspects

摘要

Microfluidic systems are miniaturized networks of microchannels processing fluids in very small quantities. A wireless microactuator suitable to drive microfluidic microvalves is discussed in this paper. A microactuator powered and controlled wirelessly, and actuated using electropermanent magnets is developed. Hard and semi-hard magnetic materials are combined to form the controllable electropermanent magnet, which is capable of holding either of the valve states without the need for continuous power consumption. Experimental data has shown that actuation occurs over a very short period of 120μs and approximately just 2mJ of energy is consumed. The key feature of the actuator is the minimal energy consumption during actuation and zero energy consumption between actuations. Wireless power capability is achieved using inductive power transfer and the same link is utilized to deliver the binary open/close signal to the actuator. The actuator is self-sustained, due to the onboard supercapacitor energy storage which stores energy to source a few thousand actuations before fully discharging and meet the peak power requirement during the very short actuation period. These state latching, wirelessly powered actuators are particularly useful in enhancing the portability, reliability and electrical safety of microfluidic applications where energy and real estate are severely limited.