Research Area
Sleep Engineering
Nonintrusive Measurement
Bio-signal based human authentication
Biomedical Signal Processing & Analysis
Sensors & Devices for u-Healthcare
Biomedical Engineering

You can use Kamagra 100mg when you want, but it's better to use it before coupling. Imagine how your wife would be delighted! She will be very happy.

 Home > RESEARCH > Research Area > Nonintrusive Measurement
 Nonintrusive measurement application (Updated 2019)

 Nonintrusive measurement

l  During our ordinary daily lives

l  Without disturbing subject’s ordinary activities

l  Without intentional cooperation for the measurements

l  Without patient’s awareness of measurement

l  Usually using devices we contact daily
(Bed, toilet seat, bath tub, shoes, watch, chair, car seat, room, belt, clothes……)

1. A chair for unconstrained physiological signal measurement

A chair system for unconstrained ECG measurement was developed. Two capacitive coupled ECG electrodes were attached to the back of the chair and a capacitive conductive sheet that was connected to the systems ground was placed under the thighs in the seat of the chair. ECG could be measured while wearing dress shirt, cotton T shirt, business suit, or cotton jeans. 

[Ref] H.J. Baek et al., A smart health monitoring chair for nonintrusive measurement of biological signals. IEEE transactions on Information Technology in Biomedicine, 2012, 16.1: 150-158.

2. Unconstrained ECG monitoring system on a toilet seat

An unconstrained ECG monitoring system with capacitive coupled electrodes installed on the toilet seat was developed. ECG was measured through both thighs. 

[Ref] J.S. Kim et al., A new approach for non-intrusive monitoring of blood pressure on a toilet seat. Physiological measurement, 2006, 27.2: 203.

3. Unconstrained ECG recording system on a bed during sleep

An unconstrained ECG monitoring system on a bed during sleep was developed. Eight capacitive coupled electrodes were fixed on the upper part of a mattress and a conductive sheet that was connected to the systems ground was placed on the lower part of the mattress. ECG was measured while a person wearing cotton pajama lay on the mattress cover. 


[Ref] Y.G. Lim et al., ECG recording on a bed during sleep without direct skin-contact. IEEE Transactions on Biomedical Engineering, 2007, 54.4: 718-725.

4. Unconstrained Blood pressure measurement using weighing scale

Unconstrained Blood pressure measurement system using a weighing scale was developed. ECG and BCG was measured from the foot, and R-J interval was calculated. Blood pressure was estimated with the R-J interval.


[Ref] J.H. Shin et al., Non-constrained monitoring of systolic blood pressure on a weighing scale. Physiological measurement, 2009, 30.7: 679.

5. Blood pressure estimation from a computer mouse

Photoplethysmographic (PPG) signal was measured from IR LED and photo diode installed on a computer mouse and ECG was measured from capacitive coupled ECG electrode attached on the back of the chair. Blood pressure was estimated from pulse arrival time (PAT) that was calculated using PPG and ECG.


[Ref] J.S. Kim et al., Development of a nonintrusive blood pressure estimation system for computer users. Telemedicine and e-Health, 2007, 13.1: 57-64.

6. Wearable system

Electrocardiogram (ECG) measurement using capacitive coupled electrode is a well-known method to get the ECG signal without direct skin-contact. In our group, the belt-type system which measures ECG without direct skin-contact is designed and tested. The system consists of developed flexible active electrode (FAE), a driven-right-leg electrode and a module for signal processing and data acquisition. The FAE has the merit of enlarging contact area. It helps to increase signal-to-noise ratio (SNR) compared to rigid and flat electrode. The measured ECG data are transmitted to a laptop computer using a Bluetooth device. The feasibility of applying the developed system to ambulatory ECG monitoring was validated by measuring ECG data during a treadmill exercise at the speed of 5km/h and 7km/h. As a result, ECG obtained from the developed wearable belt-type system was stable if a person was in a state without excessive motion. Our system is wireless and capable of non-contact ECG measurement so that it is adequate for long-term ECG monitoring.


[Ref] K.M. Lee et al., Belt-type wireless and non-contact electrocardiogram monitoring system using flexible active electrode. Int J Bioelectromagn, 2010, 12: 153-157.


2015 BMSIL/SNU All Reserved.
TEL : +82-2-2072-3135, FAX : +82-2-3676-1175, E-mail : pks@bmsil.snu.ac.kr
Department of Biomedical Engineering, College of Medicine, Seoul National University,
103, Daehak-ro, Jongno-gu, Seoul, 110-799, Republic of Korea
Supported by ONTOIN