ILLUMINATION-BASED LOCATOR ASSISTS ALZHEIMER'S PATIENTS

Context-aware computing represents an important opportunity to assist the elderly, infirm, and physically challenged. However, most methods for providing location information inside buildings require extensive hardware and installation effort. Accurately gauging indoor location with a portable computing device remains a challenge. Talking Lights, in collaboration with MIT’s Electrical Engineering and Computer Science Department, is using modulated illumination as a locator means for context-aware systems. The systems use ordinary fluorescent fixtures, incandescent table lamps, and compact fluorescent lamps with standard bulbs and wiring to provide an inherent spatial sampling. An appropriate power electronic circuit can modulate illumination to encode information without perceptible visual flicker.1 Simply replacing a fluorescent lamp ballast turns the lamp into a Talking Light transmitter. The optical illumination signal is naturally at a higher power level than other dedicated transmitters (such as Bluetooth, IR beacons, or wireless LANs). The modulated illumination supplies a unique signal precisely associated with its location. A mobile computer or PDA equipped with an optical receiver then processes the signal. The resultant specific location information lets application software achieve context awareness.2 We previously reported on this technology as a prototype guiding system for traumatic brain injury patients.3 We also have used the system to address the tendency of Alzheimer’s patients to seek exits. In preliminary trials, patients followed audio guidance and weren’t antagonized or disoriented by the disembodied voices emanating from the portable devices. We continue to research using illumination as locators for context awareness. Illumination transmitters and receivers are available from Talking Lights for other workers in the field to evaluate and use. For more information, contact Neil Lupton atmoc.sthgil-gniklat@lien.