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Capacitive sensors are common ubiquitous sensing devices that permeate through many industries. The overwhelming majority of touchscreens use capacitive sensor arrays for the precise detection of touch. Many MEMS sensors use capacitance as the variable that is manipulated to detect the sensed parameter (e.g. accelerometers). However, the use of non-rigid, ambient, or custom capacitive sensor arrays has not seen the same level of adoption. CSAs (capacative sensor arrays) can be made from a wide array of materials and techniques-including 3d printing and laser ablation-to rapidly create CSAs that can be custom fit to enable proximity, force, and touch detection. This work investigates some of these materials and how they can be fabricated in a laboratory environment with a single robotic arm.
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Daisy-Chaining Embedded Processors for Enhanced Capacitive Sensor Array Resolution
Capacitive sensing technology is widely applied in ubiquitous sensing. Its low-power consumption enables it to be used in a wide variety of Industry 4.0 applications. Capacitive Sensors can be combined into Arrays (CSAs) with mutual capacitive sensing to reduce external wiring requirements. For instance, the Texas Instruments (TI) MSP430FR2676 can capture and process data from 8×8 capacitive sensor grids. However, it is limited to supporting only 64 sensors. We propose a design incorporating daisy-chaining of CSAs via the I2C serial protocol to enable support for 256 sensors. We also demonstrate a rapid prototyping implementation of 128 sensors. The extended work we plan is to implement the prototype on custom Printed Circuit Boards (PCB) and maximize data update frequency. This architecture can find relevance in industries like manufacturing and farming, enhancing precision in the interaction between robots and humans/objects.
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- Award ID(s):
- 2237945
- PAR ID:
- 10510380
- Publisher / Repository:
- IEEE
- Date Published:
- ISBN:
- 979-8-3503-0858-7
- Page Range / eLocation ID:
- 166 to 167
- Format(s):
- Medium: X
- Location:
- Springdale, AR, USA
- Sponsoring Org:
- National Science Foundation
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