2013CYH

洪振淵 (Chen-Yuan Hung)

Development of Reversible, Wireless and Passive Micro Inertial Switches

可回復之無線被動式微慣性開關的研發

Wireless sensors are popular recently, and it can reduce the cost of wires. Wireless sensors can monitor the environments in the high temperature or acid, and it is convenient to install due to its wire-free. The character of the passive sensors is, its energy is given from outside when measuring. There are three benefits with passive sensors. First, energy instrument is easier to fix and maintain outside. Second, it can save energy because it needs energy only when measuring. Third, it doesn’t need the batteries. And the Micro Inertial Switches can record the maximum acceleration, so it is good for passive measuring. The Signal of the switches is big enough to tell when switching.

This thesis focuses on Developing of Reversible, wireless and Passive Micro Inertial Switches. And it contains the LC wireless circuit, micro inertial switches and the thermal actuators. It can record the maximum acceleration by measuring the resonance frequency with the LC circuits, then it can reversible with the thermal actuators.

The results are divided into three parts:

First, the wireless micro inertial switches can record the different acceleration by LC circuits wirelessly. When it is unlatching, its resonance frequency is 9.388 MHz; when it is on the first latch, its acceleration is 32.78 G, and its resonance frequency is 7.974 MHz; when it is on the second latch, its acceleration is 47.69 G, and its resonance frequency is 7.075 MHz.

Second, the wireless thermal actuators can be driven by LC circuits wirelessly. Its capacitance is 4.4 uF, and its inductance is 14.315 uH, its resonance frequency is 20.054 kHz. When the entering frequency is 20 kHz, it can produce the maximum current by mutual inductance, and it can drive the thermal actuator wirelessly.

Third, Reversible, wireless, and Passive Micro Inertial Switches, it can be driven by the LC circuits. And the displacement of the cantilever beam’s end is 17 um. It can unlatch but can’t be reversible because the mass touches the substrate.

[1] K.-Y. Jiang, H.-L. Chen, W. Hsu, Y.-K. Lee, Y.-W. Miao, Y.-C. Shieh, and C.-Y. Hung (October 2012). A Novel Suspension Design for MEMS Sensing Device to Eliminate Planar Spring Constants Mismatch. The 11th IEEE Conference on Sensors, Taipei, Taiwan.

[2] S.-Y. Wu, C.-Y. Hung, and W. Hsu (April 2014). A Wireless Micro Thermal Actuator Powered through LC Circuits. The 9th Annual IEEE International Conference on Nano/Micro Engineered and Molecular Systems, Hawaii, U.S.A..

[3] S.-Y. Wu, C.-Y. Hung, Y.-C. Shieh, and W. Hsu (April 2014). Wireless Shock Recording through The Integration of LC Circuits and Micro Mechanical-latch Switch. The 9th Annual IEEE International Conference on Nano/Micro Engineered and Molecular Systems, Hawaii, U.S.A..