고려대학교

초록/요약

Objective: This study proposes a vibration pattern that provides optimal directional information, 'front, back, left, and right' through a double-line vibration (haptic) feedback interface for attention-dispersed pedestrians. Background: There have been few devices that provide directional information to people with visual and hearing impairments while walking, while traffic accidents are on the rise due to the increase in the use of smartphones. Additional information such as touch is getting more desired because visual and auditory information to be provided is often limited due to crowdy and noisy surroundings. A wearable device worn in the part of the body, for example, the wrist, can easily provide such intuitive directional information through vibration or haptic feedback in various patterns. Method: The research consists of two experiments. In the first experiment, we attempted to derive the optimal longitudinal distance between vibrators and intervibration time between vibrations by placing one additional circular line to the vibration (tactile) feedback interface of the proposed study. In the second experiment, three vibration patterns are defined in light of vibration continuity, area covered, and direction. We then tried to find out if there is any difference in the performance of understanding the directional information between defined vibration patterns and between single-line and double-line vibration interfaces. Results: As a result of two experiments, the longitudinal distance between vibrators should be at least 40mm and the inter-vibration time should be at least 0.05s. There was no significant difference in the performance of understanding directional information for each of the three vibration patterns. It was, however, confirmed that the performance of the double-line vibration interface was better than that of the single-line vibration interface. Conclusion: Compared to single-line bracelet-type wearable devices that have been tested in existing studies for vibration interface design, this study investigated a double-line vibration device that added another circular line of vibration interface along the longitudinal axis, first to confirm its adequacy and second to find out an ergonomically optimal design of longitudinal distance between lines and inter-vibration time. In addition, the performance of a double-line vibration interface was confirmed to be better than that of a single-line one through various vibration patterns. Accordingly, a follow-up study is proposed to derive a combination of vibration patterns that provide optimal direction information in various user postures. Application: Vibration (haptic) feedback based on the vibration layout and intervibration time derived in this study can help the manufacturer design a proper bracelet-type wearable device providing directional information. It can also serve as a navigation interface for providing the direction of walking and the direction information of potentially hazardous objects approaching to the user.