2017 年 83 巻 853 号 p. 17-00113
Navigation systems are nowadays widely used for cars though it is yet to be able to say popularized for motorcycles. While motorcycle navigation systems are not popularized yet, previous research indicates motorcyclist's high demand against a useful navigation system. The absence of useful motorcycle navigation system is an issue of current products not capable of providing navigation information efficiently. To work with the issue, information presentation design is necessary to consider the motorcyclist's characterful viewpoint movement of looking at the road surface carefully in a vertical movement. As a solution to this issue, we propose the use of head-up display for information presentation. Previous studies have revealed the amount and positions suitable to present information for motorcyclist while riding, although the timing of information presentation is yet to be discussed. Thus, in this paper, the information presentation timing to provide navigation information has been evaluated. Experiment using an immersive CAVE motorcycle simulator was conducted with the configuration of five timings between 25 m to 85 m prior to the intersection under conditions of urban street with 30 km/h speed limit. Durations of motorcyclist's viewpoint movement and five scale subjective ratings were used for evaluation. The experimental results from 10 subjects showed a statistically significant difference in subjective ratings. In conclusion, suitable information presentation timing of riding in urban streets with 30 km/h speed limit is around 40 m to 55 m prior to the target intersection.