DEVELOPMENT OF NON-CONTACT MONITORING OF HUMAN VITAL PARAMETERS

 

P. A. Kobrisev ¹, T. S. Tuykin ², A. V. Korjenevsky ²

¹ National Research Nuclear University MEPhI (Moscow Engineering Physics Institute), Kashirskoe shosse, 31, Moscow 115409, Russia

² Kotel'nikov Institute of Radio-Engineering and Electronics of Russian Academy of Sciences,  Mokhovaya 11-7, Moscow 125009, Russia

 

The paper is received on April 14, 2017

 

Abstract. Monitoring of heart and lung activity is of vital importance for elderly people and people at risk especially when they are sleeping. Changes in body impedance reflect vital parameters. A measurement system based on electromagnetic induction can monitor these changes. The important benefit is such system requires no contact with human body.  A sinusoidal signal (0,1 – 10 MHz) from the signal generator is amplified and feeds the excitation coils and thus generats the excitation field. This field penetrates the body and induces an eddy current. This eddy current leads to a re-induced magnetic field, which superimposes the excitation field. The resulting field is measured by the receiver coils. In this paper the two variants of sensor construction are presented: a transformer and a plain coil. Both of them combine excitation and measurement, and both of them can be used as wearable electronics. The parameters of coils are optimized by resonance frequency and factor of merit. The signal from coil is processed using electronics and microcontroller. The variations of signal are detected with synchronous demodulator and then passed through the low-pass filter. The result of measurement is visualized using computer application. The development should be continued to improve noise rejection and to delete motion artefacts.

Key words: impedance, pulse, respiration, coil, synchronous demodulator.

References

[1] D. Nikolaev, A. Smirnov, I. Bobrinskaya, S. Rudnev. Bioinpedansnyi analiz chelovecheskogo tela. [Bioimpedance analysis of human body]. Ìoscow, Nauka publ., 2009. (In Russian)

[2] M. Steffen, S. Leonhardt. Non-Contact Monitoring of Heart and Lung Activity by Magnetic Induction Measurement. Multichannel simultaneous magnetic induction measurement system (MUSIMITOS). Acta Polytechnica, Vol. 48, 2008, No.3

[3] M. Steffen, K. Heimann, N. Bernstein, S. Leonhardt.  Multichannel simultaneous magnetic induction measurement system (MUSIMITOS). Physiol. Meas., 2008, No.29

[4] D. Teichmann, A. Kuhn, S. Leonhardt, M. Walter. The MAIN Shirt: A Textile-Integrated Magnetic Induction Sensor Array. Sensors, 2014, No.14.

[5] A. Sergienko. Tsifrovaya obrabotka signalov. [Discrete signal processing]. Saint-Petersburg, Piter pub., 2002. (In Russian)

 

For citation:

P. A. Kobrisev, T. S. Tuykin, A. V. Korjenevsky. Development of non-contact monitoring of human vital parameters. Zhurnal Radioelektroniki - Journal of Radio Electronics, 2017, No. 4. Available at http://jre.cplire.ru/jre/apr17/10/text.pdf. (In Russian)