Telemedicine System

A system of telemedicine is being developed by us. It employs the following approach: Advanced sens-ing, signal processsens-ing, and public telecommunication are used for clinical monitoring of the patients located in their own community, and for transmitting only the pertinent information, on line, to a med-ical professional at a hospital at distance. The medmed-ical professional interacts with the patient remotely, through audio and video links, and simultaneously examines the data transmitted by the monitor-ing system, and does medical assessment, diagnosis, and prescription. The medical professional may consult with other professionals, on line, and may also use other available resources in arriving at the diagnosis and prescription. The use of human medical professionals to perform health assessment, diag-nosis, and prescription is far more desirable than the popular approach to telemedicine and telehealth

Process 1:

Industrial robot

Process 2:

Fish processing machine Control

server

Control server Web-server

Video-streaming server

Camera (pan/tilt/zoom) + microphone Internet

Remote workstation

FIGURE 1.12 Hardware architecture of the networked system.

where an automated system may provide medical advice based on the input generated by the patient, which is known to be biased and prone to error. A schematic diagram of the proposed system is shown in Figure 1.13. The relevant issues of development and instrumentation of the system are listed as follows:

• Integrated mechatronic design of the sensor jacket to be worn by the subject for online health monitoring

• Selection of the embedded sensors and hardware, particularly with respect to their type, size, and features for acquiring the vital information from the subject

• Sensor location and configuration in the jacket to improve/optimize the process of data acquisition

• Power requirements and flexibility

• Signal processing and communication hardware on the sensor jacket

• Software for signal processing, artifact removal, data reduction, interpretation and representation within the host computer at the patient end, for transmission to the doctor’s computer

• Graphical user interface (GUI) at both ends (patient location and doctor location)

• Assistive methodologies for fast and accurate communication of information from the host com-puter at the patient end to the doctor

Wireless transmission

tower

Monitoring room in community center

Nearest hospital

Medical user

station Doctor

station 1 Doctor station 2 Secondary

monitoring station

Camera and microphone

Camera and microphone

User wearing sensor jacket

Camera and microphone Modem and

router

Modem and router Distance = 10 km

Local network

Medical network Internet

Camera and microphone

FIGURE 1.13 Structure of the telemedicine system.

In the design of the sensor jacket, a mechatronic (optimal) approach that uses an MDQ as the per-formance function is used. The design indices in the MDQ include aspects as component location, accuracy, speed, size, complexity, maintainability, design life, reliability, robustness, fault tolerance, reconfigurability, flexibility, cost, user-friendliness, and performance expectations. Parameters such as sensor location and configuration in the jacket are selected so as to improve/optimize the process of data acquisition, body conformability, weight, robustness, cost, and so on.

Selection of the sensors and associated hardware, particularly with respect to their type, size, and features to match the performance specifications of the system (as established in the mechatronic design) is an important aspect of the development of the sensor jacket. Pertinent sensors for the jacket are

• Standard ECG sensors (skin/chest electrodes)

• Blood pressure sensors (arm cuff-based monitor)

• Temperature sensors (temperature probe or skin patch)

• Respiratory sensors (piezoelectric/piezoresistive sensors)

• Electromyogram (skin electrodes)

• Oximetry sensor

• Electrical stethoscope (neck and lung)

• Pure light ear clip sensor

• Circular stretch sensor

Some of the commercially available pertinent sensors and their key features are given as follows:

Digital stethoscope (Agilent Technologies; 4.5 V dc, 1 mA):

• Captures sounds from heart and lungs

• Signals have to be amplified before acquisition by computer

• Eight levels of sound amplification

• Active noise filtering

• Mode selection: Standard diaphragm and bell modes, and extended diaphragm mode to hear high-frequency sounds (e.g., produced by mechanical heart valve prostheses)

Digital ECG recorder (Fukuda Denshi, 12-Lead Digital ECG Unit, 100–240 V/50–60 Hz ac adapter):

• Captures full electrocardiogram and forms a data file

• Built-in software to process and interpret the signals (to assist diagnosis of some types of heart problems by doctor)

• Channel (lead) selection feature (to output different types of processed information) Imaging, blood pressure, temperature, and blood oxygen sensing:

• Medical CCD camera: AMD Telemedicine, 110–220 V ac, 50–60 Hz or 12 V dc, with built-in illu-mination source

• Digital blood pressure monitor: Bios Diagnostics or Omron, 110–230 V ac adapter, PC connectiv-ity; provides blood pressure and pulse rate; cuff is inflated by pressing a button

• Digital ear thermometer: Becton Dickinson and Co./Advanced Monitors Corp

• Pulse oximeter: Devon Medical Products; mounting on fingertip or earlobe is typical; forehead and chest models are available as well

Note: Blood pressure and temperature readings may be wirelessly transmitted to patient-end computer by embedding low-power miniature transceivers into the sensors.

Sensor power supply capabilities: The following off-the-shelf sensors have built-in ac adapters (100–240 V universal, 50–60 Hz).

• ECG unit

• Medical CCD camera

• Blood pressure monitor

Stethoscope, thermometer, and pulse oximeter are typically powered by disposable batteries.

Other types of sensors, particularly, wearable ambulatory sensors/monitors (WAMs) may be inte-grated as well. The accessories required for the jacket include

• Complete low power integrated analog front end for ECG applications

• One piece ECG cable with lead wire

• Yokemate LWS^® 3-lead universal adapter

• Dry electrode

• AMC&E reusable DIN connector lead wire, 3-lead, snap connection

• Step-down converter with bypass mode for ultra-low-power wireless applications

• Needle to clip converter

• De2 development and education board

• Arduino micro

• BLE 4.0 module

• Soft potentiometer

• Wearable kit (textile push button, conductive thread etc.)

• Pressure vest

A graphic representation of the sensor jacket is given in Figure 1.14.