Wireless and Non-contact ECG Measurement System – the “Aachen SmartChair”

A Aleksandrowicz,S Leonhardt

doi:10.14311/974

Abstract

This publication describes a measurement system that obtains an electrocardiogram (ECG) by capacitively coupled electrodes. Fordemonstration purposes, this measurement system was integrated into an off-the-shelf office chair (so-called “Aachen SmartChair”).Whereas in usual clinical applications adhesive, conductively-coupled electrodes have to be attached to the skin, the described system is able to measure an ECG without direct skin contact through the cloth. A wireless communication module was integrated for transmitting theECG data to a PC or to an ICU patient monitor. For system validation, a classical ECG with conductive electrodes and an oxygensaturation signal (SpO2) were obtained simultaneously. Finally, system-specific problems of the presented device are discussed.

Highlights

Electrocardiography is one of the most important diagnostic methods to monitor proper heart function
For ECG measurement conductive electrodes have been applied which are directly attached to the skin
With the help of contact gel, they provide direct resistive contact to the patient. These electrodes possess various disadvantages which are not optimal for long-term use in a “Personal Healthcare” scenario: as a result drying of the contact gel and surface degradation of the electrodes, the transfer resistance may change with time

Summary

Introduction

Electrocardiography is one of the most important diagnostic methods to monitor proper heart function It is used in a clinical environment but more and more applied to the “Personal Healthcare” scenario. With the help of contact gel, they provide direct resistive contact to the patient These electrodes possess various disadvantages which are not optimal for long-term use in a “Personal Healthcare” scenario: as a result drying of the contact gel and surface degradation of the electrodes, the transfer resistance may change with time. Capacitive (insulated) electrodes, which can obtain an ECG signal without conductive contact to the body, even through clothes, represent an alternative. This kind of electrodes were first described by Richardson [2]. Two ECG applications with a chair have been presented [4, 5] that are somewhat similiar to the work decribed below

Methods

Discussion

Conclusion