Low-Noise and Cost-Effective Active Electrodes for Dry Contact ECG Applications
DOI:
https://doi.org/10.15407/scine18.01.112Keywords:
ECG, active electrodes, dry contactAbstract
Introduction. Active ECG electrodes for daily usable wearable electronics (glasses, headphones) enable making long-term cardiovascular disease diagnostics available to many people.
Problem Statement. The methods of ECG recording become more accessible over the years. However, on the way to their general use, even in cases where only reliable registration of the R-wave of the ECG is important, there are certain difficulties associated with the need to apply special electrodes (eg, silver chloride ones) to certain parts of the body through wet pads and to perform specific actions. The problem is solved by using dry electrodes built into the usual devices. However, in this case, a low amplitude of the useful signal and a high contact resistance (for example, on the surface of the head) do not allow recording an ECG by conventional means.
Purpose. The purpose of this research is to develop easy-to-use body ECG electrodes that may be built into everyday appliances.
Materials and Methods. Active electrodes based on flexible conductive materials and high-quality operational amplifiers have been described. The main parameters of the electronic circuit have been obtained by model and experimental research. The parameters have been compared with the corresponding characteristics of commercial samples.
Results. Prototype active ECG electrodes have been developed, created, and studied. The obtained results have shown that the dependence of the input reactance on the frequency plays an important role in terms of the final signal quality. For a low-amplitude ECG signal, the prototype has shown a signal-to-noise ratio that is higher by 4.7 dB than that for high-quality commercial electrodes.
Conclusions. The designed electrodes may be used in body devices, on the body parts with a low amplitude of the useful signal and a high resistance of skin-electrode contact.
References
World Health Organization, Cardiovascular diseases (CVDs). URL: https://www.who.int/news-room/fact-sheets/detail/cardiovascular-diseases-(cvds) (Last accessed: 19.07.21).
Searle, A., Kirkup, L. (2000). A direct comparison of wet, dry and insulating bioelectric recording electrodes. Physiological Measurement, 21(2), 271-283. https://doi.org/10.1088/0967-3334/21/2/307
Boehm, A., Yu, X., Neu, W., Leonhardt, S., Teichmann, D. (2016). A Novel 12-Lead ECG T-Shirt with Active Electrodes. Electronics, 5(4), 1-15. https://doi.org/10.3390/electronics5040075
Huang, J., Cai, Z. (2020). Using Flexible Curved Noncontact Active Electrodes to Monitor Long-Term Heart Rate Variability. Journal of Healthcare Engineering, 2020, 1-18. https://doi.org/10.1155/2020/8867712
Peng, S., Xu, K., Bao, S., Yuan, Y., Dai, C., Chen, W. (2021). Flexible Electrodes based Smart Mattress for Monitoring Physiological Signals of Heart and Autonomic Nerves in A Non-Contact Way. IEEE Sensors Journal, 21(1), 6-15. https://doi.org/10.1109/JSEN.2020.3012697
Lim, Y. G., Kim, K. K., Park, K. S. (2007). ECG Recording on a Bed During Sleep Without Direct Skin-Contact. IEEE Transactions on biomedical engineering, 54(4), 718-725. https://doi.org/10.1109/TBME.2006.889194
Peng, S., Xu, K., Chen, W. (2019). Comparison of Active Electrode Materials for Non-Contact ECG Measurement. Sensors (Basel), 19(16), 1-18. https://doi.org/10.3390/s19163585
Sidikova, M., Martinek, R., Kawala-Sterniuk, A., Ladrova, M., Jaros, R., Danys, L., Simonik, P. (2020) Vital Sign Monitoring in Car Seats Based on Electrocardiography, Ballistocardiography and Seismocardiography: A Review. Sensors (Basel), 20(19), 1-28. https://doi.org/10.3390/s20195699
Jung, S. J., Shin, H. S., Chung, W. Y. (2012). Highly sensitive driver health condition monitoring system using nonintrusive active electrodes. Sensors and Actuators B: Chemical, 71-172, 691-698. https://doi.org/10.1016/j.snb.2012.05.056
Geddes, L., Valentinuzzi, M. (1973). Temporal changes in electrode impedance while recording the electrocardiogram with "Dry" electrodes. Annals of Biomedical Engineering, 1, 356-367. https://doi.org/10.1007/BF02407675
Han, D. K., Hong, J. H., Shin, J. Y., Lee, T. S. (2009, September). Accelerometer based motion noise analysis of ECG signal. World Congress on Medical Physics and Biomedical Engineering, (September 7-12, 2009, Munich, Germany), 198-201. https://doi.org/10.1007/978-3-642-03904-1_56
Lee, J., Kim, M., Park, H. K., Young, Kim I. Y. (2020). Motion Artifact Reduction in Wearable Photoplethysmography Based on Multi-Channel Sensors with Multiple Wavelengths. Sensors (Basel), 20(5), 1-14. https://doi.org/10.3390/s20051493
Wiard, R. M., Inan, O. T., Argyres, B., Etemadi, M., Kovacs, G., Giovangrandi, L. (2011). Automatic detection of motion artifacts in the ballistocardiogram measured on a modified bathroom scale. Medical & Biological Engineering & Computing, 49(2), 213-220. https://doi.org/10.1007/s11517-010-0722-y
Waller, A. D. (1887) A demonstration on man of electromotive changes accompanying the heart's beat. The Journal of Physiology, 8(5), 229-234. https://doi.org/10.1113/jphysiol.1887.sp000257
Lewes, D. (1965). Electrode jelly in electrocardiography. British Heart Journal, 27(1), 105-115. https://doi.org/10.1136/hrt.27.1.105
Lopez, A., Richardson, P. C. (1969) Capacitive Electrocardiographic and Bioelectric Electrodes. IEEE Transactions on Biomedical Engineering, BME-16(1), 99-99. https://doi.org/10.1109/TBME.1969.4502613
Kosierkiewicz, T. (2013). Dry and Flexible Elastomer Electrodes Outperform Similar Hydrogel and Ag/AgCl Electrodes. IEEE International Symposium on Medical Measurements and Applications (MeMeA) (4-5 May, 2013, Gatineau, Canada), 306-308. https://doi.org/10.1109/MeMeA.2013.6549757
An, X., Stylios, G. K. (2018). A hybrid textile electrode for electrocardiogram (ECG) measurement and motion tracking. Materials (Basel), 11(10), 1-18. https://doi.org/10.3390/ma11101887
Chi, Y. M., Deiss, S. R., Cauwenberghs, G. (2009) Non-contact low power EEG/ECG electrode for high density wearable biopotential sensor networks. Wearable and implantable body sensor networks, sixth international workshop (5 July, 2009), 246-250. https://doi.org/10.1109/BSN.2009.52
Sullivan, T. J., Deiss, S. R., Cauwenberghs, G. (2007, November). A Low-Noise, Non-Contact EEG/ECG Sensor. IEEE Biomedical Circuits and Systems Conference, (27-30 November, 2007, Montreal, Canada), 154-157. https://doi.org/10.1109/BIOCAS.2007.4463332
Prance, R. J., Debray, A., Clark, T. D., Prance, H., Nock, M., Harland, C. J., Clippingdale, A. J., (2000). An ultra low noise electrical-potential probe for human-body scanning. Measurement Science and Technology, 11(3), 291-297. https://doi.org/10.1088/0957-0233/11/3/318
Spinelli, E., Haberman, M. (2010). Insulating electrodes, a review on biopotential front ends for dielectric skin-electrode interfaces. Physiological Measurement, 31(10), 183-198. https://doi.org/10.1088/0967-3334/31/10/S03
Harland, C. J., Clark, T. D., Prance, R. J. (2002). Electric potential probes-new directions in the remote sensing of the human body. Measurement Science and Technology, 13(2), 163-169. https://doi.org/10.1088/0957-0233/13/2/304
Bai, W., Zhu, Z., Li, Y., Liu, L. (2018). A 64.8μW >2.2GΩ DC-AC Configurable CMOS Front-End IC for Wearable ECG Monitoring. IEEE Sensors Journal, 18(8), 1-10. https://doi.org/10.1109/JSEN.2018.2809678
He, D. D., Winokur, E. S., Sodini, C. G. (2015). An Ear-Worn Vital Signs Monitor. IEEE Transactions on Biomedical Engineering, 62(11), 2547-2552. https://doi.org/10.1109/TBME.2015.2459061
AN5354, Application note. Getting started with the STM32H7 Series MCU 16-bit ADC. URL: https://www.st.com/ resource/en/application_note/dm00628458-getting-started-with-the-stm32h7-series-mcu-16bit-adc-stmicroelectronics.pdf (Last accessed: 03.06.21).
DS12110 Rev 7, STM32H742xI/G STM32H743xI/G reference manual. URL: https://www.st.com/resource/en/reference_manual/dm00314099-stm32h742-stm32h743753-and-stm32h750-value-line-advanced-armbased-32bit-mcus-stmicroelectronics.pdf (Last accessed: 03.06.21).
DocID024030 Rev 7, STM32F427xx/STM32F429xx reference manual. URL: https://www.st.com/resource/en/reference_manual/dm00031020-stm32f405415-stm32f407417-stm32f427437-and-stm32f429439-advanced-armbased-32bit -mcus-stmicroelectronics.pdf (Last accessed: 03.06.21).
Kamal, S., Efaz, E. T., Alam, F., Rana, M. (2020). Development of A Low-Cost Real-Time Bioelectrical Signal Acquisition Module. 2nd International Conference on Sustainable Technologies for Industry 4.0 (STI), (19-20 December 2020, Dhaka, Bangladesh), 1-6. https://doi.org/10.1109/STI50764.2020.9350473
Scher, A. M., Young, A. C. (1960). Frequency Analysis of the Electrocardiogram, Circulation Research, 8, 344-346. https://doi.org/10.1589/jpts.25.753
Thakor, N., Webster, J., Tompkins, W. (1984). Estimation of QRS Complex Power Spectra for Design of a QRS Filter. IEEE Transactions on Biomedical Engineering, BME-31(11), 702-706. https://doi.org/10.1109/TBME.1984.325393
Pan, J., Tompkins, W. (1985). A Real-Time QRS Detection Algorithm. IEEE Transactions on Biomedical Engineering, 32(3), 230-236. https://doi.org/10.1109/TBME.1985.325532
PS25255 EPIC Ultra High Impedance ECG Sensor Advance Information. Data Sheet 291955 issue 1. URL: http:// www.saelig.com/supplier/plessey/PS25255.pdf (Last accessed: 03.06.21).
A Python program that plots Bode plots of a component using a Rigol DS1054Z Oscilloscope and a JDS6600 DDS Generator. URL: https://github.com/jbtronics/DS1054_BodePlotter (Last accessed: 03.06.21).
Kester, W. (2009) Understand SINAD, ENOB, SNR, THD, THD + N, and SFDR so You Don't Get Lost in the Noise Floor. MT-003 tutorial. URL: https://www.analog.com/media/en/training-seminars/tutorials/MT-003.pdf (Last accessed: 03.06.21).
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