Title :
A dynamic ultrasonic ranging system as a mobility aid for the blind
Author :
Gao, Robert X. ; Li, Chum
Author_Institution :
Inst. for Micromanuf., Louisiana Tech. Univ., Ruston, LA, USA
Abstract :
A microprocessor-based ultrasonic ranging system, configured around a PVC tube resembling the form of a long cane, has been designed. The system, intended to serve as a mobility aid for the blind, consists of four ultrasonic sensors integrated into the cane, and a microcontroller. It is able to provide real-time information on the distance and height of over-hanging obstacles within 5 meters along the travel path ahead of the user. Laboratory experiments under various cane motion patterns have shown that at 5 meters, the maximum relative error of the measurement is below 14%. This drops to less than 5%, when the measurement range is within 3 meters. Upon miniaturization, the system can be integrated into a conventional long cane for practical daily use by the blind
Keywords :
biomedical ultrasonics; distance measurement; handicapped aids; height measurement; microcomputer applications; microsensors; real-time systems; sensory aids; ultrasonic transducers; vision defects; 5 m; PVC tube; blind; cane motion patterns; dynamic ultrasonic ranging system; four ultrasonic sensors; laboratory experiments; long cane; measurement error; microcontroller; microprocessor-based ultrasonic ranging system; miniaturization; mobility aid; over-hanging obstacles; practical daily use; real-time information; travel path; Biomedical measurements; Control systems; Ergonomics; Micromechanical devices; Motion measurement; Protection; Sensor systems; Time of arrival estimation; USA Councils; Ultrasonic transducers;
Conference_Titel :
Engineering in Medicine and Biology Society, 1995., IEEE 17th Annual Conference
Conference_Location :
Montreal, Que.
Print_ISBN :
0-7803-2475-7
DOI :
10.1109/IEMBS.1995.579864
