A Wireless Method For Monitoring Medication Compliance

guineanscarletElectronics - Devices

Nov 27, 2013 (2 years and 11 months ago)


A Wireless Method For
Monitoring Medication

A thesis by

Jeffrey S. Jonas

Dr. Manikopoulos, advisor





sensor networks


Take your medicine!

Medication compliance (taking one’s medicine as
prescribed) is a major concern because it is a
leading cause of preventable hospitalization.

5.5% of hospital admissions can attributed to
drug therapy noncompliance

Outpatient deaths due to medication errors
increased by 8.48
fold in the US

7391 died in 1993 due to medication errors

There are many pill dispensers to
help you remember your meds

And some transmit their status

But they are very expensive

Scope of project

Prototype low cost methods for remote
medication compliance

Make it modular for allow configuration
flexibility and cost control

“Play nicely with others” (participate in larger
monitoring systems)

Research the responsibilities of data control
once gathered

The “Baby Monitor” model


Low cost

An appliance: little to no user interface

Owner controls the operation and costs

Information Overload!

Intense activity in related areas

advances in low power embedded devices,
sensors & cryptography

RFID deployment, standardization and

Ubicomp has come of age

wireless networks
are ubiquitous (WAN, WiFi, PAN)

Interdisciplinary approach

The “value added” to this thesis is the breadth of
research and correlation of concerns and
requirements to technological solutions.

Integrate new technologies

Wireless networks are small and easy to
integrate, and come in all sizes (WAN, PAN)

MEMS enables accurate, continuous monitoring
of things that were previously unobservable.
Closed loop control systems can now be applied
to medicine.

Telemedicine integrates many inputs

RFID buzz

RFID is the "next big thing" for inventory
tracking. The pharmaceutical industry is
exploring RFID to thwart counterfeiting, in
addition to U.S. government mandates.

CVS’ “Jump Start” RFID trial was coordinated
with the AUTO
ID Center with HIPAA and
privacy concerns from the start.

Drug Counterfeiting

Prior Research

“Magic medicine Cabinet”

Kenneth Fishkin’s work at Intel Research
Seattle: exploring man/machine interface with
UbiComp, RFID (linking physical objects to the
virtual word), RFID privacy, eldercare, RFID in

Fishkin Medicine Monitoring Pad

The Prototypes

Modified Candy Dispenser

Uses COTS parts

Transmitters may be similar to wireless mice,
keyboards, game controllers

RKE (Remote Keyless Entry) fobs offer a
variety of security

Prototype #2

The pillbox was modified to detect pills in 3
different ways


Reflective optical sensor

“electric eye”

2 modes of operation

The sensors are monitored by a PIC 18f252

Connecting a cellular phone to the RS232 port
enables stand
alone operation by transmitting
change of container status via SMS (text

A wired or wireless connection to a PC is also
supported for data collection and forwarding

Prototype demonstration

Future Enhancements

The candy dispenser:

Embed a RKE with strong encryption such as
Microchip’s KeeLoq rolling code

Removable tray for cleaning

Compartments for different sized pills

Future Enhancements

The pillbox:

Try other sensors such as pressure, weight,
capacitance to detect pills reliably.

Use missing pulse detection to prevent ambient
light interference

Add tilt, motion, e
field sensors to report
handling and to prevent pill status errors.

Future Enhancements

When used with a cellular phone

Read the notification number(s) from the phone
(it was hard
coded in the prototype).

Allow multiple numbers for notifying several

Add real time clock for daily summaries instead
of real
time event reporting

Enhancements (con’t)

Expand the SMS (text messaging) command
processing to a full chat script similar to UUCP
or modem dialers to support other command

Convert from polling to interrupt based I/O
with watchdog timer to prevent blocking if
communications fail.

Enhancements (con’t)

When connected to a PC via wireless link

Use a secure communications protocol for
authentication and to prevent injection of false
data into the data collection system.

Digitally sign the status so the archives are

Recessed buttons for restricted activities such
as firmware upgrade

Sensor wish

The ideal sensor is one that requires no power to
sense the activity (container open/close) but
holds the state until read and electrically reset. A
latching magnetic reed switch is too large for
this application. A MEMS bistable switch would
be ideal if latched by a magnet or other external

RFID tags can be tiny

Hitachi Mu chip: 2.45 GHz, 128 bit ROM

Implantable RFID: 125 kHz, 54 bit ROM

How tiny?

RFID tags (particularly anti
theft tags) are already
embedded into devices and containers where the
customer may not know they exist. They have
no “off” switch and are often hard to remove.

RFID Privacy

Medical records are confidential. Data generated
at home is often shared with caregivers and
doctors thus the need for data assurance.
HIPAA applies to the data once shared, but the
patient ought to be empowered to set the
sharing policy.

RFID blocking

Temporary or permanent deactivation

“zapper”, removal, sever the antenna

Permanent kill command vs. reversible
sleep/wake commands

RSA block tag: interferes with tree walking
algorithm: replies to all addresses, or just a

RFID Guardian

ELINT in your pocket


A mobile battery
powered device that offers
personal RFID


Key management

Access control


RFID Guardian

Allows full control of RFID activity within your
personal space

Location aware: different profiles depending on

Notification of RFID scanning

Audit trail of all activity

Allows per
tag access, blocking or proxy

Empowers total control of all personal RFID.


There are many aspects to medical assistance,
particularly how to control access and
dissemination of personal data. Data assurance
must be designed into the system from inception
if it is to be trusted and resist attacks. A smart
pill dispenser is just the tip of the iceberg.

Thank you!

Questions ?