Development of a high-speed current injection and voltage measurement system for electrical impedance tomography-based stretchable sensors

Russo, S; Nefti-Meziani, S; Carbonaro, N; Tognetti, A

Abstract

In common EIT systems, the voltage data are serially measured by means of multiplexers, and are hence collected at slightly different times, which affects the real-time performance of the system. They also tend to have complicated hardware, which increases power consumption. In this paper, we present our design of a 16-electrode high-speed EIT system that simultaneously implements constant current injection and differential potential measurements. This leads to a faster, simpler-to-implement and less-noisy technique, when compared with traditional EIT approaches. Our system consists of a Howland current pump with two multiplexers for a constant DC current supply, and a data acquisition card. It guarantees a data collection rate of 78 frames/s. The results from our conductive stretchable fabric sensor show that the system successfully performs voltage data collection with a mean signal-to-noise ratio (SNR) of 55 dB, and a mean absolute deviation (MAD) of 0.5mV. The power consumption can be brought down to 3mW; therefore, it is suitable for battery-powered applications.
Finally, pressure contacts over the sensor are properly reconstructed, thereby validating the efficiency of our EIT system for soft and stretchable sensor applications.

Citation

Russo, S., Nefti-Meziani, S., Carbonaro, N., & Tognetti, A. (2017). Development of a high-speed current injection and voltage measurement system for electrical impedance tomography-based stretchable sensors. Technologies, 5(3), 48. https://doi.org/10.3390/technologies5030048

• Journal Article Type: Article
• Acceptance Date: Jul 21, 2017
• Online Publication Date: Jul 26, 2017
• Publication Date: Jul 26, 2017
• Deposit Date: Aug 29, 2017
• Publicly Available Date: Aug 29, 2017
• Journal: Technologies
• Electronic ISSN: 2227-7080
• Publisher: MDPI
• Volume: 5
• Issue: 3
• Pages: 48
• DOI: https://doi.org/10.3390/technologies5030048
• Publisher URL: http://dx.doi.org/10.3390/technologies5030048
• Related Public URLs: http://www.mdpi.com/journal/technologies
• Additional Information: Projects : Smart-e