JPH11327642A - Radio wave reflection type lane mark - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the receiving intensity of radio waves by providing a road with a radio wave reflection type lane mark in order to reflect radio waves which are transmitted from a vehicle and have a prescribed flare angle and making the lane mark form an arc-shaped reflection plane that is almost perpendicular to the progressing direction of the radio waves. SOLUTION: Plural pieces of recessed grooves 2 which have radio wave reflection planes 2a which are almost perpendicular to the progressing direction of radio waves and radio wave reflection planes 2b which form 90 deg. corners to the reflection planes and face them and present circular arc shapes from the viewpoint of a flat plane are formed on the surface of a radio wave reflection type lane mark 1 made of a metallic plate in its length direction and in prescribed intervals. And, incident beams 3 are made incident on the planes 2a at almost right angles and reflected beams 4 are further reflected by the planes 2b so that they can be reflected radially against the beams 3 from the viewpoint of a flat plane and almost parallelly with them from the viewpoint of a side. Thus, the receiving intensity of radio waves can be increased and the position of a vehicle is easily detected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio-reflective lane mark laid on a road surface as equipment for enabling automatic driving of a car on a highway or the like.

[0002]

2. Description of the Related Art As a lane mark of this kind, Japanese Utility Model No. 1
A light reflecting tape such as that described in JP-A-106910 is known, but this light reflecting tape is not practical because it is easily affected by disturbances such as sunlight and nighttime illumination.

[0003]

Therefore, a method of irradiating a radio wave to a lane mark laid on a road surface and detecting the position of the vehicle based on the reflection intensity has been considered.
At this time, it is desirable that the transmitted radio wave is always incident on the lane mark so that its reflection intensity is maximized. In some cases, the intensity of the reflected radio wave becomes small, and in this case, there is a problem that it is difficult to detect the position of the vehicle.

Accordingly, the present invention has been made to solve the above-mentioned conventional problems, and to provide a radio wave reflecting lane mark which can increase the reception intensity of radio waves and can easily detect the position of a vehicle. Aim.

[0005]

According to one aspect of the present invention, there is provided a radio wave reflecting lane laid on a road surface to reflect a radio wave having a predetermined divergence angle transmitted from a vehicle. The mark is characterized by having an arc-shaped reflecting surface that is substantially perpendicular to the traveling direction of the radio wave. According to a second aspect of the present invention, in the first aspect, the reflecting surface is:
It is characterized by being arcuate in the vehicle width (lane width) direction. According to a third aspect of the present invention, in the first or second aspect, the reflection surface is formed in an arc shape in a vertical direction.

According to a fourth aspect of the present invention, there is provided a radio wave reflecting lane mark laid on a road surface for reflecting a radio wave having a predetermined divergence angle transmitted from a vehicle, wherein the lane mark is provided at a predetermined distance in a traveling direction of the radio wave. And the predetermined distance is set in accordance with the wavelength of the transmission radio wave so that the radio waves reflected by each reflection surface reinforce each other. The invention of claim 5 is the invention of claim 4
Wherein the reflection surface is formed in an arc shape in the vehicle width (lane width) direction and / or the vertical direction.

[0007]

An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a plan view showing a configuration of a lane mark laid on a road surface of a road. In the drawing, only a part of the lane mark in the length direction is shown. FIG. 2 is an enlarged sectional view of a main part along the line AA in FIG. Reference numeral 1 denotes a lane mark, which is made of a metal plate. On the upper surface of the lane mark 1, a concave groove 2 having a radio wave reflecting surface 2a substantially perpendicular to the traveling direction of the radio wave (running direction) and a radio wave reflecting surface 2b forming a 90 ° corner and facing the reflecting surface 2b are formed. Are formed in a circular arc shape when viewed from the plane, and are formed at predetermined intervals in the length direction. The arc of the concave groove 2 is formed so as to be convex in a direction opposite to the traveling direction of the radio wave. Numeral 3 indicates an incident direction of a radio wave (beam), and numeral 4 indicates a reflection direction. In the configuration of the lane mark 1 as described above, if the interval between the concave grooves 2 is d, the depression center value of the reflected radio wave is θ °, n is 0, 1, 2,. 1 is established.

## EQU1 ## 2π / λ · dSinθ ° = nπ

Next, the operation will be described. The electric wave is transmitted from a vehicle traveling at a predetermined spread angle. The transmitted incident beam 3 always enters the radio wave reflecting surface 2a at a substantially right angle. The beam 4 reflected by the radio wave reflecting surface 2a is further reflected by the radio wave reflecting surface 2b so as to be radial with respect to the incident beam 3 as viewed from a plane and substantially parallel as viewed from the side as shown in FIG. As described above, the reflected beam 4 is reflected radially as viewed from the plane, so that even if the vehicle has a slight lateral deviation and the detector in the vehicle is displaced in the lateral direction, the reflected beam 4 can be easily received. And the position of the vehicle can be measured. As a result, it is possible to prevent the reception intensity from decreasing, which often occurs in the related art. In addition, the radio waves 4 reflected by the reflecting surfaces 2a and 2b of the plurality of concave grooves 2 reinforce each other due to the relationship between the wavelength and the distance d between the reflecting surfaces, so that the receiving intensity increases.

The above-mentioned radio wave reflecting surface 2a is formed in an arc shape when viewed from a plane as shown in FIGS. 1 and 2, and is formed in a non-circular straight line when viewed from a cross section. However, when viewed from a cross section as shown in FIG. May be a reflecting surface 2'a formed in an arc shape in the up-down direction. In this case, the reflected beam 4 can be reflected in the up-down direction with a predetermined spread with respect to the incident beam 3, so that the vibration of the vehicle can be reduced. As a result, even if the reflected radio wave fluctuates, the reception intensity of the detector further increases.

FIGS. 4 and 5 show another embodiment. FIG. 4 is a plan view showing the configuration of the lane mark, and only a part of the lane mark in the length direction is shown in the drawing. FIG. 5 is an enlarged sectional view of a main part along the line BB of FIG. 11 is a lane mark,
The difference between the lane mark 1 and the lane mark 1 is that the groove 12 is not formed in an arc shape when viewed from a plane, but is formed in a straight line.
A point formed in a vertical arc shape when viewed from the cross section. The radio wave reflection surface 12a facing the radio wave reflection surface 12a has the same configuration as the radio wave reflection surface 2b except that the radio wave reflection surface 12a does not have a circular arc on a plane. When the radio wave reflecting surface 12a of the concave groove 12 is formed in this manner, the incident beam 3 is formed in a manner similar to that shown in FIG.
There is an advantage that the reflected beam 4 can be reflected with a predetermined spread in the vertical direction.

Each of the embodiments described above is a preferred example, and it is a matter of course that the present invention is not limited to these embodiments. Therefore,
The implementation can be arbitrarily changed or modified within the scope of the technical contents described in the claims.

[0012]

According to the first to third aspects of the present invention, since there is provided an arc-shaped reflecting surface which is substantially perpendicular to the traveling direction of the radio wave, the reception intensity of the reflected radio wave can be increased. It is possible to easily detect the position of the vehicle. The invention according to claims 4 and 5 is as described above, comprising a plurality of reflecting surfaces formed at predetermined intervals in the traveling direction of the radio waves, and transmitting the radio waves reflected by each reflecting surface so as to reinforce each other. Since the predetermined distance is set in accordance with the wavelength of the radio wave, the radio waves reflected on each reflection surface of the plurality of concave grooves reinforce each other due to the relationship between the wavelength and the reflection surface interval, and the reception intensity is further increased. There is an excellent effect of increasing the size.

[Brief description of the drawings]

FIG. 1 is a plan view showing a configuration of a lane mark according to an embodiment of the present invention.

FIG. 2 is an enlarged sectional view of a main part taken along line AA of FIG.

FIG. 3 is an enlarged sectional view of a main part showing a modified example of the reflection surface of the concave groove.

FIG. 4 is a plan view showing a configuration of a lane mark according to another embodiment.

FIG. 5 is an enlarged sectional view of a main part along a line BB in FIG. 4;

[Explanation of symbols]

 1 lane mark 2 concave groove 2a, 2'a, 2b radio wave reflecting surface 3 incident beam 4 reflected beam 11 lane mark 12 concave groove 12a, 12b radio wave reflecting surface

[Procedure amendment]

[Submission date] May 14, 1999

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Claims

[Correction method] Change

[Correction contents]

[Claims]

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0005

[Correction method] Change

[Correction contents]

[0005]

According to one aspect of the present invention, there is provided a radio wave reflecting lane laid on a road surface to reflect a radio wave having a predetermined divergence angle transmitted from a vehicle. A mark having a plurality of reflection surfaces formed at predetermined intervals in the traveling direction of the radio wave, and the predetermined distance according to the wavelength of the transmission radio wave so that the radio waves reflected by each reflection surface reinforce each other. Is set. According to a second aspect of the present invention, in the first aspect, the reflecting surface is formed in an arc shape in a vehicle width (lane width) direction and / or a vertical direction.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0006

[Correction method] Deleted

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0012

[Correction method] Change

[Correction contents]

[0012]

According to the first and second aspects of the present invention, there are provided a plurality of reflecting surfaces formed at predetermined intervals in a traveling direction of a radio wave, and the radio waves reflected by each of the reflecting surfaces are formed. Since the predetermined distance is set in accordance with the wavelength of the transmission radio wave to reinforce each other, the radio waves reflected by each reflection surface of the plurality of concave grooves will reinforce each other due to the relationship between the wavelength and the reflection surface interval. This has an excellent effect that the reception intensity of the reflected radio wave can be increased and the position of the vehicle can be easily detected.

Claims (5)

[Claims] 1. A lane mark reflecting a radio wave laid on a road surface to reflect a radio wave having a predetermined divergence angle transmitted from a vehicle, wherein the lane mark has an arc shape substantially perpendicular to a traveling direction of the radio wave. A radio-reflective lane mark having a reflective surface. 2. The radio wave reflecting lane mark according to claim 1, wherein the reflecting surface has an arc shape in the vehicle width direction. 3. The radio wave reflecting lane mark according to claim 1, wherein the reflecting surface has an arc shape in a vertical direction. 4. A radio wave reflecting lane mark laid on a road surface to reflect a radio wave having a predetermined divergence angle transmitted from a vehicle, wherein the plurality of lane marks are formed at predetermined intervals in a traveling direction of the radio wave. And the predetermined distance is set in accordance with the wavelength of the transmission radio wave so that the radio waves reflected by each reflection surface reinforce each other. 5. The radio wave reflecting lane mark according to claim 4, wherein the reflecting surface is formed in an arc shape in a vehicle width direction and / or a vertical direction.