499 / 2019-02-28 15:46:22

Walkability Evaluation with VR for International Street Boundary-Space Design

全体主题 > Information Technology & Expert Systems

Topics
Information Technology & Expert Systems, Planning Support Systems/Science

Background and Aim
In the car-oriented society due to motorization, road development has been carried out more for car users and roadside walking spaces for pedestrians have been given lower priority. In Japan, sidewalk spaces are often developed to provide the minimum levels of convenience and safety where people can walk with less obstacles and conflicts against cars. However, in recent years, problems of population decline and aging increasingly require urban compaction and walkable spaces.
One of the important street improvements is to provide walking spaces to encourage people to walk. It is suggested that pedestrians’ interests are attracted by street activities including on-street behaviors of staying, stopping and sitting. While such street activities tend to be in the boundary space of sidewalks on building side, streets in Japan often lack the street design to generate the street activities, such as benches, stalls and open cafes. On the other hand, recent changes of transport systems, such as bike sharing, car sharing and autonomous vehicles, also have potential to change street design of the boundary space on road side. While these are expected to improve the convenience and attractiveness of travel on street, there is a concern that the conflicts of pedestrians against other pedestrians and vehicles could worsen the safety and comfort of walk. Accordingly, it is necessary to improve street design elements, particularly on the road side and the building side, taking account of their impacts on various needs of walk.
The evaluation of street design with respect to walk needs requires the experience of walking for such needs, but walking experience in one country is limited for this, as street improvements pay more attention to the convenience and safety of walk in Japan. Although it is not realistic to have actual experiences of walking on overseas streets, recent advancement of visualization technologies, represented by the VR tools, makes it possible to virtually experiences various overseas walking environments. Particularly, 360-degree cameras, which can make videos with the 360 view, and Head Mound Display (HMD), which can watch the 360 videos in the immersive virtual environments, become more available at the reasonable prices. Moreover, VR is a planning support tool not only for the evaluation tool of street design, but also for the information tool to provide information of new street environments for unfamiliar walk needs, such as comfort and attractiveness, through virtual walk. Accordingly, this research carries out street evaluation using the VR tools for international walking environments to capture the impacts on walk needs of the street design elements, particularly the internationally different boundary-space ones.

Methodology
First, the indicators of street design elements are sort out by a literature review, paying attention to the street design of the boundary spaces on the road side and the building side. Then, to capture the diversity of international street design , the indicators are measured by making the 360 movies of case study streets with the 360 camera, RICOH THETA V. The case study areas include streets near the main stations in city centers in Nagoya (Japan), Bangkok (Thailand), Brisbane and Canberra (Australia).
Finally, the experimental surveys of street-design evaluation and walk-need evaluation for the case study streets are conducted to analyze the influence of street design elements, particularly boundary-space ones, on walk needs. In the experiment, 50 undergraduate students in Japan watched the 360 movies of the international case study streets with HMD, Oculus Rift . After watching the movies, the subjects answered a questionnaire to subjectively rate each street in terms of both street design elements and walk needs with the scale of 1-10 points.
Results
The international comparison of street design indicators showed that, streets in Nagoya have more on-street parking cycles, streets in Australia have more benches, open cafes, people stopping and sitting, streets in Bangkok have more parking cars and motorbikes and more venders. The results of the VR surveys showed that the boundary street-design elements have great influences on walk needs, in which the road-side elements and the building-side elements have different influences on multiple walk needs. This implies the potential of the VR application to street planning to provide information of new visions of street environments beyond what can be experienced in daily life.

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