Mutual capacitance of liquid conductors in deformable tactile sensing arrays
- Electrical and Computer Engineering Department, Drexel University, Philadelphia, Pennsylvania 19104 (United States)
- Electrical and Computer Engineering and Materials Science and Engineering Departments, Drexel University, Philadelphia, Pennsylvania 19104 (United States)
- Electrical and Computer Engineering Department, Media Arts and Technology, California NanoSystems Institute, University of California, Santa Barbara, California 93106 (United States)
Advances in highly deformable electronics are needed in order to enable emerging categories of soft computing devices ranging from wearable electronics, to medical devices, and soft robotic components. The combination of highly elastic substrates with intrinsically stretchable conductors holds the promise of enabling electronic sensors that can conform to curved objects, reconfigurable displays, or soft biological tissues, including the skin. Here, we contribute sensing principles for tactile (mechanical image) sensors based on very low modulus polymer substrates with embedded liquid metal microfluidic arrays. The sensors are fabricated using a single-step casting method that utilizes fine nylon filaments to produce arrays of cylindrical channels on two layers. The liquid metal (gallium indium alloy) conductors that fill these channels readily adopt the shape of the embedding membrane, yielding levels of deformability greater than 400%, due to the use of soft polymer substrates. We modeled the sensor performance using electrostatic theory and continuum mechanics, yielding excellent agreement with experiments. Using a matrix-addressed capacitance measurement technique, we are able to resolve strain distributions with millimeter resolution over areas of several square centimeters.
- OSTI ID:
- 22489259
- Journal Information:
- Applied Physics Letters, Vol. 108, Issue 1; Other Information: (c) 2016 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); ISSN 0003-6951
- Country of Publication:
- United States
- Language:
- English
Similar Records
Wearable Microfluidic Diaphragm Pressure Sensor for Health and Tactile Touch Monitoring
Self-Sensing, Stretchable, Active Circuit Arrays: Liquid Metal Paste as a Combination Interconnect and Strain Sensor