Liquid metal-based bio-inspired capacitive flow sensor

James P. Wissman; Kaushik Sampath; Charles A. Rohde

doi:10.1117/12.2514355

13 March 2019 Liquid metal-based bio-inspired capacitive flow sensor

James P. Wissman, Kaushik Sampath, Charles A. Rohde

Proceedings Volume 10965, Bioinspiration, Biomimetics, and Bioreplication IX; 109650T (2019) https://doi.org/10.1117/12.2514355
Event: SPIE Smart Structures + Nondestructive Evaluation, 2019, Denver, Colorado, United States

Abstract

We present a liquid flow sensor inspired by cupula structures found on a variety of fish. Our 5mm x 5mm x 1.75mm artificial cupula uniquely comprises a pair of differential liquid metal capacitors encased in silicone. Deflection of the structure – manually or by fluid flow – increases capacitance on one side and decreases on the other. To fabricate the complex internal structure, a commercial 3D printer is used to create a mold out of a sacrificial wax-like material. After casting uncured rubber, internal mold structures are melted and dissolved away, leaving channels and voids for liquid metal vacuum injection. The measured sensitivity of ~0.05pF/mm is compared to theoretical capacitance versus deflection values based on kinematics. To test behavior under water flow, a custom flow channel consisting of a 7.5mm x 7.5mm cross-section is employed with rates up to 1L/min. The parabolic capacitive response as a function of flowrate is compared to analytic theory based on kinematics and drag as well as to fluid-structure interaction (FSI) simulations using COMSOL. This device has future applications in the control of bio-inspired soft robotics. [Work sponsored by the Office of Naval Research.]

Conference Presentation

Citation Download Citation

James P. Wissman, Kaushik Sampath, and Charles A. Rohde "Liquid metal-based bio-inspired capacitive flow sensor", Proc. SPIE 10965, Bioinspiration, Biomimetics, and Bioreplication IX, 109650T (13 March 2019); https://doi.org/10.1117/12.2514355

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available