Wearable Computing – Medical Applications

Alexander Nelson

April 4th, 2018

University of Arkansas - Department of Computer Science and Computer Engineering

Mobile Health

mHealth – Mobile Health – practice of medicine supported by

mobile devices

Wearable Medical Device Market – Estimated $14.1B by 20221

(For reference, global smartphone sales ∼ $479B)

1https://www.researchandmarkets.com/research/n699wt/global wearable?w=5

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mHealth

mHealth has immediate impact to low- and middle- income

countries and rural areas

Simple functions (such as SMS) can produce extensive results2

2Mechael, Patricia N. Exploring health-related uses of mobile phones: an

Egyptian case study. London school of hygiene and tropical medicine, 2006.

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Approaches to mHealth

Approaches:

• Helpline

• Education/Training

• Diagnostic by patient input

• Remote monitoring by

mobile sensing

• Continuous monitoring by

wearable sensors

Star Trek Medical Tricorder3

Medical Body Area Network

MBAN – Medical Body Area Network

“Consists of medical devices that communicate in and around the

human body”3

3G. Fang et al, ”Medical Body Area Networks: Opportunities, challenges and

practices,”

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Challenges

Challenges to MBANs:

• Power Constraints – Must be able to operate long-term on

little power

• Robust Communication – Communication must not fail for

critical devices

• Data Quality – Data should be of sufficient precision/accuracy

to make inference

• Interoperability – Devices should work together for holistic

health

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Challenges (continued)

Challenges to MBANs:

• Communication Co-existence – Limited spectrum must be

utilized properly

• Cost – Cannot be overly burdensome on patient

• Constancy – Mission critical must operate constantly

• Constrained Deployment – Unobtrusive/Calm/Invisible

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Usability and Invisibility

An MBAN device should operate unobtrusively with little/no

thought

e.g. Pacemaker – Implanted, only operates when needed

Users make trade-offs on Invisibility based on a devices usefulness

i.e. The more useful a system, the more obtrusive it may be

however

Systems should attempt to be as unobtrusive as possible – not

altering daily activities

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Communications

MBANs often need to send data to a remote processor/aggregator

Communication Channels:

• WBAN communications – ZigBee, BLE, NFC, etc...

• Wired communications – Some technologies may need

low-power or high-speed communications provided by wired

connections

• Galvanic coupling intrabody communication (IBC) – Use of

the human body as a communication channel

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Intra-body Communication

2-4MHz frequencies along skin attenuate around -18dB for this

handshake

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On-Body Computation

Smart Tattoos – Instrumentation of the skin through metallic or

biological tattoos

(Left) Gold-leaf metallic circuits as temporary tattoo

(Right) Bio-luminescent ink as indicators of physiological values

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Data Security and Privacy

Medical Devices are subject to data privacy legislation & data

must be handled with care

Data must be encrypted as close to the sensed value as possible

• Active Attack – Adversary can eavesdrop and inject

communication within MBAN communication

• Passive Attack – Adversary can only eavesdrop on

communication

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