A walk support system that can provide visually impaired users with information about objects touched by a cane. The goal of the proposed system is to identify five objects, i.e., two types of braille blocks, a pedestrian crossing, the floorboard of a train, and a train gateway, using a cane. Previous studied adopted electronic devices, e.g., RFID tags, to evaluate identification. Conversely, the proposed system employs phosphor powder, a chemical that can emit specific light wavelengths upon optical excitation. The proposed system does not require significant changes to the construction process of identified objects. The phosphor powder is mixed with the construction materials prior to construction. Thus, as compared with method using RFID tags, the proposed system does not require pre-calculation of the proper number and location of tags or changes to the construction method, which are needed for burying RFID tags. We created a specimen from a synthetic resin shaped like a braille block and observed the emission excited by an LED light source. Results demonstrated that more light emission could be observed when the weight percentage and power of the light increased and the distance between prove and the specimen decreased. The peak wavelength could also be seen even though the distance between the prove and specimen was increased. Thus, we confirmed that phosphor powder could be used as the guide object for the proposed walk support system.
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