This manuscript presents airborne jet propulsion by audio sounds and ultrasounds through orifices formed by bulk-micromachining of a silicon wafer. The propeller is integrated with a small, printed circuit board (PCB) with a DC/DC converter, an oscillator, and a power amplifier, all powered by a 100F lithium-ion capacitor to make the propeller operable wirelessly. The peak propulsion force of the wireless propeller is measured to be 63.1 mg (or 618 mN) while the packaged wireless propeller’s weight is 10.6 g, including the drive electronics and adapter) when driven by 2.5kHz sinusoidal voltage with 21.4Vpp. A wired propeller (with 563 mg weight without adapter) is shown to high jump, long jump, wobbly fly, and propel objects. Also, the propeller is shown to work when driven by ultrasounds with a maximum propulsion force of 8.4 mg (82 mN) when driven by 20kHz, 20Vpp sinusoidal signal. Varying the frequency gradient of the applied sinusoidal pulses is shown to move the propeller to the left or right on demand to reach a specific location.
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WIRELESS AND STAND-ALONE SUBMARINE PROPELLER BASED ON ACOUSTIC PROPULSION
This paper presents a wireless and stand-alone subminiature propeller based on acoustic propulsion for the underwater robotic applications. The acoustic propulsion is generated by a MEMS-based self-focusing acoustic transducer (SFAT), fabricated on 1-mm-thick lead zirconate titanate (PZT) substrate, and operated at its thickness mode resonant frequency of 2.32 MHz. A 100F lithium-ion capacitor (LIC) is used as a power source due to its high energy and power densities. A drive electronic circuit is implemented on a flexible printed circuit board (PCB) and delivers 30Vpp sinusoidal signal to the acoustic propeller. The completed system is 18 x 18 x 38 mm3 in volume and weighs 12.56 grams, resulting in a mass density of 1.020 g/cm3. The acoustic propulsion generated by the acoustic propeller is measured to be 18.68μN with the electrical power of 358.7mW consumed by the propeller. Both vertical and horizontal propulsions are demonstrated successfully in sodium polytungstate (SPT) solution.
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- Award ID(s):
- 2017926
- NSF-PAR ID:
- 10329990
- Date Published:
- Journal Name:
- Hilton Head Workshop 2022: A Solid-State Sensors, Actuators and Microsystems Workshop
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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