Proposal for application to the roundabout traffic system of the image hump and symbol sign utilizing the illusion effect

 Tamio HOSHIKA ／ SOJO UNIVERSITY

2．Study content

１）Speed method of suppression by the image hump utilizing the illusion effect before into the roundabout.

　Roundabout is an intersection there is no signal. Therefore, there is a need for psychological and physical method for suppressing speed as shown in figure 1. Figure 2 is a zig-zag pattern image hump that utilize optical illusion effect. Production of uneven effect of the illusion effect, as well as improve the speed suppressing effect by the sound and shock. It has designed just to ride of the tire moving car in the V-shaped portion. V-shaped line is transmitted sound and shock because it is with the warts.(patent pending).

Figure 2: Zigzag format image hump to be installed in the roundabout in front

２）Symbolic art design system in the roundabout.

Symbol art sign in the circular space is responsible for the landmark role of environmental design in the region. Intersection since generally there is the entrance of four places from three points, the visual impression at the time of entry is important. In this report, we describe the effective representation in the visual impression with from the entrance explore the construction method. FIG. 3 is a work called "encore" of Shigeo Fukuda work. It is a reference case of the three-dimensional object to produce a different visual impression in each direction.And FIG.4 is obtained by the plan of the concept simple design construction methods. It is a design example that was a combination of initials of city areas and symbols of the areas.

 

Figure 3: symbol sign of the reference case "Encore" / Shigeo Fukuda work in 1976

 

Figure 4: symbol sign visible to the different impression in four directions

３）Guidance sign system to the roundabout passing car

Induction sign indicating the direction around the rotary is also necessary.From the point of view of landscape design, considering the balance of the symbol art sign, general guidance signage is not beautiful. In this report, we propose a design system that arrow emerges with the viewpoint movement. Obliquely arranging a plurality of rods as shown in Fig. Field of view even better, and driver can enjoy change of vision.

Figure 5: symbol sign visible to the different impression by viewpoint position

Review

　In this study, it was the proposal of three for roundabout traffic system. One is speed method of suppression by the image hump utilizing the illusion effect before into the roundabout, the other one is the method of symbolic art design system in the roundabout, and the other one is the guidance sign system to the roundabout passing car.The research results, hopes to lead to beautiful making Japan the road environment.