Development of walking assistive cane for obstacle detection and location recognition for visually impaired people

Visually impaired people generally use a white cane for safe walking owing to its advantages of familiarity, reliability, low cost, and usability, but it is difficult to detect low obstacles with a cane. Although electronic walking assistive canes equipped with various sensors are being developed to solve several problems, these devices cannot be used by visually impaired people owing to their very high prices and insufficient reliability. We have developed a new walking assistive cane for visually impaired people that uses three ultrasonic sensors, a vibration motor, a radio frequency identification (RFID) reader and tags, a speaker, a cadmium sulfide photoresistor, and an LED. An experimental environment with cylindrical obstacles and RFID was designed to evaluate its effectiveness. Ten participants with normal vision were recruited, and they walked blindfold through the experimental environment three times using a normal white cane and three times using the developed cane. In the experiment, walking with the developed cane showed higher obstacle detection performance than walking with a normal white cane. However, the walking speed of the user was lower using the developed cane. According to the results of a questionnaire on the satisfaction of walking with the developed cane, recognition of the current location became easier with the use of RFID but the detection range of RFID should be further increased. The cane developed in this study can be manufactured inexpensively, and the effect of the weight of the cane on the user is reduced by attaching a wheel to its tip to allow it to be pushed forward rather than swung from side to side. This is a basic study on improving the satisfaction of spatial perception ability when transmitting spatial information to visually impaired people using RFID, and its results can be used to develop electronic travel aids in the future.