The Sidsa Personal Locator for Alzheimer Patients
From: Information Quarterly, Volume 1 - Issue 1 - 2002 - page 45
Authors: Peter Bishop, Atmel and Joaquin Lopez Contreras, Sidsa

People suffering from Alzheimer's disease are constantly at risk of getting
lost. A shopping trip in the neighborhood can turn into a nightmare when the
person is unable to find his or her way home. The solution of having someone
to accompany the person is too costly and interferes with their liberty. 

A cost-effective solution developed by Sidsa in Spain comprises a small
battery-powered locator that is carried by the Alzheimer sufferer whenever he
or she ventures outside. By a combination of GPS and GSM technology, this
locator is in permanent contact with a central monitoring station. The
monitoring station can keep track of a large number of locators, each of
which is programmed with a permitted geographic area, and the duration of the
excursion. If the person being monitored strays outside his or her permitted
area, or stays away from home longer than the permitted time, an alert is
sounded, and the person can be retrieved.  

The locator is housed in a compact pack that can be carried in a pocket or
handbag. The pack also contains the RF antennae and interfaces for GSM and
GPS, as well as memory and a SIM card. The locator has no external controls;
it is configured and activated entirely from a programming unit that is kept
at the central monitoring station. This is to avoid any problems arising from
the disability of the people using the device. 

Read the entire story at:
http://www.convergencepromotions.com/IQ/issue1/AT91_Alzheimer.pdf

Links:
http://www.sidsa.com/explorer/index_ex.htm
http://www.us.design-reuse.com/news/news4055.html