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Title: Passive metamaterial-based acoustic holograms in ultrasound energy transfer systems
Contactless energy transfer (CET) is a technology that is particularly relevant in applications where wired electrical contact is dangerous or impractical. Furthermore, it would enhance the development, use, and reliability of low-power sensors in applications where changing batteries is not practical or may not be a viable option. One CET method that has recently attracted interest is the ultrasonic acoustic energy transfer, which is based on the reception of acoustic waves at ultrasonic frequencies by a piezoelectric receiver. Patterning and focusing the transmitted acoustic energy in space is one of the challenges for enhancing the power transmission and locally charging sensors or devices. We use a mathematically designed passive metamaterial-based acoustic hologram to selectively power an array of piezoelectric receivers using an unfocused transmitter. The acoustic hologram is employed to create a multifocal pressure pattern in the target plane where the receivers are located inside focal regions. We conduct multiphysics simulations in which a single transmitter is used to power multiple receivers with an arbitrary two-dimensional spatial pattern via wave controlling and manipulation, using the hologram. We show that the multi-focal pressure pattern created by the passive acoustic hologram will enhance the power transmission for most receivers.  more » « less
Award ID(s):
1711139
PAR ID:
10064617
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Passive metamaterial-based acoustic holograms in ultrasound energy transfer systems
Volume:
10595
Page Range / eLocation ID:
43
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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