JPH09210905A - Sensing device for road surface moistness with laser - Google Patents
Sensing device for road surface moistness with laserInfo
- Publication number
- JPH09210905A JPH09210905A JP8019724A JP1972496A JPH09210905A JP H09210905 A JPH09210905 A JP H09210905A JP 8019724 A JP8019724 A JP 8019724A JP 1972496 A JP1972496 A JP 1972496A JP H09210905 A JPH09210905 A JP H09210905A
- Authority
- JP
- Japan
- Prior art keywords
- laser
- wavelength
- road surface
- wavelength laser
- intensity
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
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Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
- Y02A90/00—Technologies having an indirect contribution to adaptation to climate change
- Y02A90/10—Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation
Landscapes
- Measurement Of Optical Distance (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
- Optical Radar Systems And Details Thereof (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、レーザによる路面
湿分検出装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a road surface moisture detecting device using a laser.
【０００２】[0002]
【従来の技術】レーザ光を用いた距離測定方法として、
三角測量方式，パルス方式，変調方式，等が知ら
れている。図４は、三角測量方式の原理図であり、半導
体レーザの出射光が投光レンズにより細い光ビームに変
換され対象物に投射される。光ビームは対象物の表面で
反射されるが、これは表面上の光点として観察される。
対象物が図の矢印の方向に沿って変位すると、光点の位
置は光ビームの光軸上で移動する。この光点は光ビーム
とαの角度をなす光軸を有する受光レンズにより、半導
体光位置検出素子上に結像される。半導体光位置検出素
子（ＰＳＤ）は、半導体の表面抵抗を利用し、走査を行
わないで入射光の位置を検出するものである。図では光
点Ｐ1 ，Ｐ2 がそれぞれＰＳＤ上のＰ1 ′，Ｐ2 ′に結
像されている。ＰＳＤにより結像点の位置を検出すれ
ば、それから対象物の変位（すなわち位置）を算出する
ことができる。2. Description of the Related Art As a distance measuring method using laser light,
Triangulation method, pulse method, modulation method, etc. are known. FIG. 4 is a principle diagram of the triangulation method, in which emitted light of a semiconductor laser is converted into a thin light beam by a light projecting lens and projected onto a target object. The light beam is reflected at the surface of the object, which is observed as a light spot on the surface.
When the object is displaced along the direction of the arrow in the figure, the position of the light spot moves on the optical axis of the light beam. This light spot is imaged on the semiconductor light position detecting element by a light receiving lens having an optical axis forming an angle α with the light beam. The semiconductor light position detection element (PSD) utilizes the surface resistance of the semiconductor and detects the position of incident light without scanning. In the figure, light spots P 1 and P 2 are imaged on P 1 ′ and P 2 ′ on the PSD, respectively. If the position of the image formation point is detected by PSD, the displacement (that is, position) of the object can be calculated therefrom.
【０００３】また、パルス方式では、レーザ光をパルス
波で投射し、対象物で反射されたパルス波を検出するま
での時間から距離を測定するものである。更に、変調方
式では、変調したパルス波を投射し、対象物で反射され
たパルス波の変調の変化を検出して距離を測定するもの
である。In the pulse method, laser light is projected as a pulse wave and the distance is measured from the time until the pulse wave reflected by the object is detected. Further, in the modulation method, a modulated pulse wave is projected, a change in modulation of the pulse wave reflected by the object is detected, and the distance is measured.
【０００４】また、レーザを用いて離れた位置の状態を
検知する手段として、レーザーレーダ装置が知られてい
る。このレーザーレーダ装置では、上述のパルス方式に
より距離を計測すると共に、ダイアル（Differential A
bsorption Lider ：ＤＩＡＬ）と呼ばれる技術、すなわ
ち、レーザ光を２波長投光し、一方の波長は対象物質
（窒素酸化物，硫黄酸化物等）の吸収波長を用いること
により、同光路において対象物があると、散乱光の強度
変化に差が発生するため、その差を利用して物質の検知
ができるようになっている。A laser radar device is known as a means for detecting the state of a remote position using a laser. In this laser radar device, the distance is measured by the pulse method described above, and the dial (Differential A
bsorption Lider (DIAL), that is, two wavelengths of laser light are projected and one wavelength uses the absorption wavelength of the target substance (nitrogen oxide, sulfur oxide, etc.) If so, a difference occurs in the intensity change of the scattered light, so that the substance can be detected by utilizing the difference.
【０００５】[0005]
【発明が解決しようとする課題】一方、路面を走行する
車両（レーシングカー、高速バス、乗用車、大型車両、
ブルドーザ等の特殊車両、等）では、運転員が窓を通し
て前方の路面を目視し、路面の状態を判断して車両を運
転するのが普通である。しかし、この場合に、高速走行
時や視界の悪い状態（霧中や暗闇中、等）では、目視に
よる運転に限界があり、水溜まりや濡れた路面に進入す
るおそれがあるため速度を極端に遅くする必要があっ
た。このため、サーキット等を走行するレーシングカ
ー、高速道路を走行する高速バス，乗用車等では高速走
行が維持できなくなり、また、大型車両、ブルドーザ等
の特殊車両、等でも安全走行が難しくなる問題点があっ
た。On the other hand, vehicles traveling on the road surface (racing cars, high speed buses, passenger cars, large vehicles,
In a special vehicle such as a bulldozer, etc.), a driver usually drives the vehicle by visually observing the road surface ahead through a window and judging the condition of the road surface. However, in this case, when driving at high speed or in a state of poor visibility (in fog or darkness, etc.), there is a limit to the visual operation, and the speed may be extremely slowed down because there is a risk of entering a water pool or a wet road surface. There was a need. For this reason, high speed running cannot be maintained in a racing car running on a circuit, a high speed bus running on a highway, a passenger car, etc., and it is difficult to safely run on a large vehicle, a special vehicle such as a bulldozer, etc. there were.
【０００６】この問題点を解決するため、上述したレー
ザーレーダ装置を車両に搭載することも検討されてい
る。しかし、上述したレーザーレーダー装置は大型で高
価であり車両搭載が実用上不可能であった。In order to solve this problem, it is also considered to mount the above-mentioned laser radar device on a vehicle. However, the above-mentioned laser radar device is large and expensive and practically impossible to mount on a vehicle.
【０００７】本発明はかかる問題点を解決するために創
案されたものである。すなわち、本発明の目的は、比較
的小型で安価な装置により、走行車両の前方の路面の湿
分（水溜まりや濡れた路面）を検出することができ、こ
れにより危険回避が可能となり、高速走行や安全走行を
維持することができるレーザによる路面湿分検出装置を
提供することにある。The present invention has been made to solve such a problem. That is, an object of the present invention is to detect moisture (puddle or wet road surface) on the road surface in front of a traveling vehicle with a relatively small and inexpensive device, which makes it possible to avoid danger and drive at high speed. Another object of the present invention is to provide a road surface moisture detecting device using a laser capable of maintaining safe traveling.
【０００８】[0008]
【課題を解決するための手段】本発明によれば、水分に
吸収されやすい第１波長レーザと吸収されにくい第２波
長レーザをそれぞれ路面に向けて投射するレーザ送光装
置と、路面で反射された第１波長レーザと第２波長レー
ザの強度をそれぞれ計測するレーザ受光装置と、投射レ
ーザと反射レーザの強度比を第１波長と第２波長に分け
て演算し、その比較から路面の湿分を検知する演算検知
装置と、を備えたことを特徴とするレーザによる路面湿
分検出装置が提供される。According to the present invention, a laser transmitting device for projecting a first wavelength laser, which is easily absorbed by moisture, and a second wavelength laser, which is less likely to be absorbed, toward the road surface, and a laser light transmitting device which is reflected by the road surface. The laser light receiving device for measuring the intensities of the first wavelength laser and the second wavelength laser, respectively, and the intensity ratio of the projection laser and the reflection laser are calculated separately for the first wavelength and the second wavelength. A road surface moisture detecting device using a laser, which is provided with a calculation detecting device for detecting.
【０００９】上記本発明の構成によれば、レーザ波長を
２波長（一方は水の吸収帯外の波長、他方は水の吸収帯
内の波長）とすることにより、測定点の水分状態（ウエ
ット又はドライ）によりその入反射強度比に差が発生す
る。従って、この差から測定点の湿分の有無（すなわ
ち、水溜まりや濡れた路面）を検知することができ、こ
れにより危険回避が可能となり、高速走行や安全走行を
維持することができる。また、上記構成によれば、この
装置は、２台のレーザ装置，２台の強度検出装置，及び
簡単な演算検知装置で構成でき、比較的小型で安価な装
置とすることができる。According to the above configuration of the present invention, by setting the laser wavelength to two wavelengths (one outside the absorption band of water and the other inside the absorption band of water), the water state (wet state) at the measurement point is measured. Or, depending on the dryness, a difference occurs in the input / reflection intensity ratio. Therefore, it is possible to detect the presence or absence of moisture at the measurement point (that is, a pool of water or a wet road surface) from this difference, which makes it possible to avoid danger and maintain high-speed traveling and safe traveling. Further, according to the above configuration, this device can be configured with two laser devices, two intensity detection devices, and a simple calculation detection device, and can be a relatively small and inexpensive device.
【００１０】本発明の好ましい実施形態によれば、第１
波長レーザの反射強度Ｉ1 ′と投射強度Ｉ1 の比Ｉ1 ′
／Ｉ1 と、第２波長レーザの反射強度Ｉ2 ′と投射強度
Ｉ2の比Ｉ2 ′／Ｉ2 とを演算し、Ｉ1 ′／Ｉ1 ＞
Ｉ2 ′／Ｉ2 の場合に路面が濡れていると判断する。こ
の構成により、簡単な演算検知装置で路面の湿分を検知
することができる。According to a preferred embodiment of the present invention, the first
The ratio I 1 ′ of the reflection intensity I 1 ′ of the wavelength laser and the projection intensity I 1
/ I 1 and the ratio I 2 ′ / I 2 of the reflection intensity I 2 ′ of the second wavelength laser and the projection intensity I 2 are calculated, and I 1 ′ / I 1 >
When I 2 ′ / I 2 , it is determined that the road surface is wet. With this configuration, it is possible to detect the moisture content on the road surface with a simple calculation detection device.
【００１１】また、本発明の好ましい実施形態によれ
ば、前記第１波長レーザの波長は、相対的に水分に吸収
されにくい波長であり、前記第２波長レーザの波長は、
相対的に水分に吸収されやすい波長である。この構成に
より、湿分の検出を効率的に行うことができる。第１波
長レーザとしては、例えばＮｄ−ＹＡＧレーザ（波長
１．０６μｍ）を用いることができ、第２波長レーザと
しては、例えばＴｍ−ＹＡＧレーザ（波長２．０１μ
ｍ）を用いることができる。Further, according to a preferred embodiment of the present invention, the wavelength of the first wavelength laser is a wavelength relatively less absorbed by water, and the wavelength of the second wavelength laser is
The wavelength is relatively easily absorbed by water. With this configuration, it is possible to efficiently detect moisture. For example, an Nd-YAG laser (wavelength 1.06 μm) can be used as the first wavelength laser, and a Tm-YAG laser (wavelength 2.01 μm) can be used as the second wavelength laser.
m) can be used.
【００１２】更に、本発明の好ましい実施形態によれ
ば、前記レーザ送光装置による第１波長レーザと第２波
長レーザの少なくとも一方を、三角測量方式の距離測定
に併用する。この構成により、湿分の有無の他に、計測
位置を正確に測定することができ、これにより適切な危
険回避が可能となり、高速走行や安全走行を一層容易に
維持することができる。Further, according to a preferred embodiment of the present invention, at least one of the first wavelength laser and the second wavelength laser by the laser light transmitting device is used together for distance measurement by the triangulation method. With this configuration, it is possible to accurately measure the measurement position in addition to the presence or absence of moisture, which makes it possible to appropriately avoid danger and more easily maintain high-speed traveling and safe traveling.
【００１３】[0013]
【発明の実施の形態】以下、本発明の好ましい実施形態
を図面を参照して説明する。なお、各図において共通す
る部分には同一の符号を付して使用する。図１は、本発
明によるレーザによる路面湿分検出装置の全体構成図で
ある。この路面湿分検出装置１０は、路面を走行する車
両１（乗用車、大型車両、ブルドーザ等の特殊車両、
等）に搭載され、前方の路面２に斜めにレーザ光を投射
するようになっている。DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. In the drawings, common parts are denoted by the same reference numerals. FIG. 1 is an overall configuration diagram of a road surface moisture detecting apparatus using a laser according to the present invention. The road surface moisture detection device 10 is a vehicle 1 that travels on a road surface (a passenger vehicle, a large vehicle, a special vehicle such as a bulldozer,
Etc., and is adapted to project laser light obliquely on the road surface 2 in front.
【００１４】図１に示すように、本発明のレーザによる
路面湿分検出装置１０は、レーザ送光装置１２、レーザ
受光装置１４、及び演算検知装置１６からなる。レーザ
送光装置１２は、水分に吸収されにくい第１波長レーザ
３ａと吸収されやすい第２波長レーザ３ｂをそれぞれ路
面２に向けて斜めに投射するようになっている。また、
レーザ受光装置１４は、路面２で反射された第１波長レ
ーザ３ｂと第２波長レーザ４ｂの強度をそれぞれ計測す
るようになっている。更に、演算検知装置１６は、投射
レーザ３ａ，４ａと反射レーザ３ｂ，４ｂの強度比を第
１波長と第２波長に分けて演算し、その比較から路面の
湿分を検知するようになっている。As shown in FIG. 1, a road surface moisture detecting device 10 using a laser of the present invention comprises a laser light transmitting device 12, a laser light receiving device 14, and a calculation detecting device 16. The laser light transmitting device 12 projects the first wavelength laser 3a, which is hardly absorbed by water, and the second wavelength laser 3b, which is easily absorbed, toward the road surface 2 at an angle. Also,
The laser receiving device 14 is adapted to measure the intensities of the first wavelength laser 3b and the second wavelength laser 4b reflected by the road surface 2, respectively. Further, the calculation detecting device 16 calculates the intensity ratio of the projection lasers 3a, 4a and the reflection lasers 3b, 4b separately for the first wavelength and the second wavelength, and detects moisture on the road surface from the comparison. There is.
【００１５】図１に示すように、演算検知装置１６で
は、第１波長レーザ３ａ，３ｂの反射強度Ｉ1 ′と投射
強度Ｉ1 の比Ｉ1 ′／Ｉ1 と、第２波長レーザ４ａ，４
ｂの反射強度Ｉ2 ′と投射強度Ｉ2 の比Ｉ2 ′／Ｉ2 と
を演算し、Ｉ1 ′／Ｉ1 ＞Ｉ2′／Ｉ2 の場合に路面が
濡れていると判断する。すなわち、濡れた路面で反射し
たレーザ光は、水分に吸収されにくい第１波長レーザ３
ｂでは通常の散乱強度であるが、水分に吸収されやすい
第２波長レーザ４ｂでは水分に吸収されるため通常の散
乱強度に比較して弱くなるので、この特性から路面の湿
分を検知することが可能となる。As shown in FIG. 1, in the arithmetic and detection unit 16, the ratio I 1 ′ / I 1 of the reflection intensity I 1 ′ and the projection intensity I 1 of the first wavelength lasers 3a and 3b and the second wavelength lasers 4a and 4a, Four
The ratio I 2 ′ / I 2 of the reflection intensity I 2 ′ of b and the projection intensity I 2 is calculated, and when I 1 ′ / I 1 > I 2 ′ / I 2 , it is determined that the road surface is wet. That is, the laser light reflected on the wet road surface is not easily absorbed by moisture
Although the normal scattering intensity is shown in b, the second wavelength laser 4b, which is easily absorbed by water, becomes weaker than the normal scattering intensity because it is absorbed by water. Therefore, it is necessary to detect the moisture content on the road surface from this characteristic. Is possible.
【００１６】図２は、水分吸収とレーザ波長の関係図で
ある。この図に示すように、相対的に水分に吸収されや
すい領域（例えば２μｍ付近）において、水分の吸収率
（透過率に反比例する）が高いが、この領域を外れた波
長（例えば１μｍ付近）では、水分の吸収率は非常に小
さくなる。従って、図２から明らかなように、前記第１
波長レーザ３ａの波長は、相対的に水分に吸収されにく
い波長であり、前記第２波長レーザ４ａの波長は、相対
的に水分に吸収されやすい波長である、ことが好まし
い。この構成により、湿分の検出を効率的に行うことが
できる。なお、第１波長レーザ３ａとしては、例えばＮ
ｄ−ＹＡＧレーザ（波長１．０６μｍ）を用いることが
でき、第２波長レーザ４ａとしては、例えばＴｍ−ＹＡ
Ｇレーザ（波長２．０１μｍ）を用いることができる。FIG. 2 is a diagram showing the relationship between water absorption and laser wavelength. As shown in this figure, the moisture absorption rate (reversely proportional to the transmittance) is high in a region relatively easy to be absorbed by moisture (for example, around 2 μm), but at a wavelength outside this region (for example, around 1 μm). , The absorption rate of water becomes very small. Therefore, as is apparent from FIG.
It is preferable that the wavelength of the wavelength laser 3a is a wavelength that is relatively difficult to be absorbed by moisture, and the wavelength of the second wavelength laser 4a is a wavelength that is relatively easily absorbed by moisture. With this configuration, it is possible to efficiently detect moisture. The first wavelength laser 3a may be, for example, N
A d-YAG laser (wavelength 1.06 μm) can be used, and the second wavelength laser 4a is, for example, Tm-YA.
A G laser (wavelength 2.01 μm) can be used.
【００１７】図３は、上述した特性を確認した試験結果
である。なお、この試験では、水分に吸収されにくい第
１波長レーザ３ａとして、Ｔｍ−ＹＡＧレーザ（波長
１．０６μｍ）を用い、水分に吸収されやすい第２波長
レーザ４ａとして、Ｈｏ−ＹＡＧレーザ（波長２．０１
μｍ）を用いた。また第１波長レーザ３ａと第２波長レ
ーザ４ａを路面２に対して同一角度で投射し、かつ第１
波長レーザ３ａと第２波長レーザ４ａの投射強度Ｉ1 ，
Ｉ2 を同一にして、反射強度Ｉ1 ′，Ｉ2 ′を計測して
反射率Ｉ1 ′／Ｉ1 及びＩ2 ′／Ｉ2 を求めた。FIG. 3 shows the test results confirming the above-mentioned characteristics. In this test, a Tm-YAG laser (wavelength 1.06 μm) is used as the first wavelength laser 3a that is hard to be absorbed by water, and a Ho-YAG laser (wavelength 2 is used as the second wavelength laser 4a that is easily absorbed by water. .01
μm). Further, the first wavelength laser 3a and the second wavelength laser 4a are projected onto the road surface 2 at the same angle, and
Projection intensity I 1 of the wavelength laser 3a and the second wavelength laser 4a,
And the I 2 to the same, the reflection intensity I 1 ', I 2' was determined by measuring the reflectance I 1 '/ I 1 and I 2' / I 2 a.
【００１８】この図から明らかなように、反射率Ｉ1 ′
／Ｉ1 とＩ2 ′／Ｉ2 の関係は、少なくとも路面２が濡
れている場合に、Ｉ1 ′／Ｉ1 ＞Ｉ2 ′／Ｉ2 の関係に
なっていることがわかる。As is clear from this figure, the reflectance I 1 ′
It can be seen that the relationship between / I 1 and I 2 ′ / I 2 has a relationship of I 1 ′ / I 1 > I 2 ′ / I 2 at least when the road surface 2 is wet.
【００１９】更に、上述した実施形態では、レーザによ
る路面湿分検出装置についてのみ説明したが、レーザ送
光装置１２による第１波長レーザ３ａと第２波長レーザ
４ａの少なくとも一方を、前述した三角測量方式の距離
測定に併用することができ、この構成により、路面の位
置測定から路面までの距離を同時に計測することがで
き、同時に路面の湿分を測定でき、これにより適切な危
険回避が可能となり、高速走行や安全走行を一層容易に
維持することができる。Further, in the above-described embodiment, only the road surface moisture detecting device using the laser has been described, but at least one of the first wavelength laser 3a and the second wavelength laser 4a by the laser light transmitting device 12 is subjected to the triangulation described above. This method can be used together with the distance measurement of the method, and with this configuration, it is possible to measure the distance from the road surface position to the road surface at the same time, and at the same time measure the road surface moisture, which enables appropriate risk avoidance. Therefore, high speed driving and safe driving can be maintained more easily.
【００２０】なお、本発明は上述した実施形態に限定さ
れず、本発明の要旨を逸脱しない範囲で種々変更できる
ことは勿論である。It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that various changes can be made without departing from the spirit of the present invention.
【００２１】[0021]
【発明の効果】上述したように本発明のレーザによる路
面湿分検出装置は、比較的小型で安価な装置により、走
行車両の前方の路面の湿分（水溜まりや濡れた路面）を
検出することができ、これにより危険回避が可能とな
り、高速走行や安全走行を維持することができる、等の
優れた効果を有する。As described above, the road surface moisture detecting apparatus using the laser of the present invention is capable of detecting the moisture (water pool or wet road surface) on the road surface in front of the traveling vehicle by a relatively small and inexpensive device. As a result, danger can be avoided, and high speed traveling and safe traveling can be maintained, which is an excellent effect.
【図１】本発明によるレーザによる路面湿分検出装置の
全体構成図である。FIG. 1 is an overall configuration diagram of a road surface moisture detecting device using a laser according to the present invention.
【図２】水分吸収とレーザ波長の関係図である。FIG. 2 is a relationship diagram between water absorption and laser wavelength.
【図３】本発明による試験結果である。FIG. 3 is a test result according to the present invention.
【図４】三角測量方式の原理図である。FIG. 4 is a principle diagram of a triangulation method.
１ 車両 ２ 路面 ３ａ 第１波長レーザ（投射レーザ） ３ｂ 第２波長レーザ（反射レーザ） ４ａ 第１波長レーザ（投射レーザ） ４ｂ 第２波長レーザ（反射レーザ） １０ 路面湿分検出装置 １２ レーザ送光装置 １４ レーザ受光装置 １６ 演算検知装置 1 Vehicle 2 Road Surface 3a First Wavelength Laser (Projection Laser) 3b Second Wavelength Laser (Reflection Laser) 4a First Wavelength Laser (Projection Laser) 4b Second Wavelength Laser (Reflection Laser) 10 Road Surface Moisture Detector 12 Laser Light Transmission Device 14 Laser receiver 16 Calculation detector
Claims (4)
吸収されやすい第２波長レーザをそれぞれ路面に向けて
投射するレーザ送光装置と、路面で反射された第１波長
レーザと第２波長レーザの強度をそれぞれ計測するレー
ザ受光装置と、投射レーザと反射レーザの強度比を第１
波長と第２波長に分けて演算し、その比較から路面の湿
分を検知する演算検知装置と、を備えたことを特徴とす
るレーザによる路面湿分検出装置。1. A laser light transmitting device for projecting a first wavelength laser that is hardly absorbed by moisture and a second wavelength laser that is easily absorbed toward a road surface, respectively, a first wavelength laser and a second wavelength laser reflected on the road surface. The laser light receiving device for measuring the intensity of each of the
A road surface moisture detection device using a laser, comprising: a wavelength detection device and a second wavelength device, which are separately calculated to detect the moisture content of the road surface based on the comparison.
強度Ｉ1 の比Ｉ1 ′／Ｉ1 と、第２波長レーザの反射強
度Ｉ2 ′と投射強度Ｉ2 の比Ｉ2 ′／Ｉ2 とを演算し、
Ｉ1 ′／Ｉ1 ＞Ｉ2 ′／Ｉ2 の場合に路面が濡れている
と判断する、ことを特徴とする請求項１に記載のレーザ
による路面湿分検出装置。2. The ratio I 1 ′ / I 1 of the reflection intensity I 1 ′ and the projection intensity I 1 of the first wavelength laser, and the ratio I 2 ′ of the reflection intensity I 2 ′ and the projection intensity I 2 of the second wavelength laser. Calculate / I 2 and
The road surface moisture detecting device according to claim 1, wherein the road surface is determined to be wet when I 1 ′ / I 1 > I 2 ′ / I 2 .
水分に吸収されにくい波長であり、前記第２波長レーザ
の波長は、相対的に水分に吸収されやすい波長である、
ことを特徴とする請求項１に記載のレーザによる路面湿
分検出装置。3. The wavelength of the first wavelength laser is a wavelength relatively less absorbed by moisture, and the wavelength of the second wavelength laser is a wavelength relatively easily absorbed by moisture.
The road surface moisture detecting device using a laser according to claim 1, wherein:
ザと第２波長レーザの少なくとも一方を、三角測量方式
の距離測定に併用する、ことを特徴とする請求項１乃至
３に記載のレーザによる路面湿分検出装置。4. The laser according to claim 1, wherein at least one of the first wavelength laser and the second wavelength laser by the laser light transmitting device is used together for distance measurement of a triangulation method. Road moisture detector.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8019724A JPH09210905A (en) | 1996-02-06 | 1996-02-06 | Sensing device for road surface moistness with laser |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8019724A JPH09210905A (en) | 1996-02-06 | 1996-02-06 | Sensing device for road surface moistness with laser |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH09210905A true JPH09210905A (en) | 1997-08-15 |
Family
ID=12007264
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8019724A Pending JPH09210905A (en) | 1996-02-06 | 1996-02-06 | Sensing device for road surface moistness with laser |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH09210905A (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009199154A (en) * | 2008-02-19 | 2009-09-03 | Ihi Corp | Puddle detection device, unmanned traveling vehicle, and puddle detection method |
| KR101307178B1 (en) * | 2013-01-28 | 2013-09-11 | 공주대학교 산학협력단 | Identification methods of road weather conditions in dual wavelength road weather condition monitoring apparatus |
| JP2015535204A (en) * | 2012-09-20 | 2015-12-10 | グーグル インコーポレイテッド | Road weather condition detection |
| JP2017183904A (en) * | 2016-03-29 | 2017-10-05 | セコム株式会社 | Region detection device |
| CN110312924A (en) * | 2017-02-24 | 2019-10-08 | 松下知识产权经营株式会社 | Aridity sensor |
| CN114537425A (en) * | 2022-02-28 | 2022-05-27 | 重庆长安汽车股份有限公司 | Detection early warning method and device for front deceleration strip and ditch bank during driving and vehicle |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6428544A (en) * | 1987-07-23 | 1989-01-31 | Mitsui Mining & Smelting Co | Method and apparatus for measuring quality of fruit |
| JPH05256941A (en) * | 1992-03-13 | 1993-10-08 | Honda Motor Co Ltd | Fm radar apparatus |
| JPH07198341A (en) * | 1993-12-28 | 1995-08-01 | Nec Corp | Water film measurement device |
-
1996
- 1996-02-06 JP JP8019724A patent/JPH09210905A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6428544A (en) * | 1987-07-23 | 1989-01-31 | Mitsui Mining & Smelting Co | Method and apparatus for measuring quality of fruit |
| JPH05256941A (en) * | 1992-03-13 | 1993-10-08 | Honda Motor Co Ltd | Fm radar apparatus |
| JPH07198341A (en) * | 1993-12-28 | 1995-08-01 | Nec Corp | Water film measurement device |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009199154A (en) * | 2008-02-19 | 2009-09-03 | Ihi Corp | Puddle detection device, unmanned traveling vehicle, and puddle detection method |
| JP2015535204A (en) * | 2012-09-20 | 2015-12-10 | グーグル インコーポレイテッド | Road weather condition detection |
| KR101307178B1 (en) * | 2013-01-28 | 2013-09-11 | 공주대학교 산학협력단 | Identification methods of road weather conditions in dual wavelength road weather condition monitoring apparatus |
| JP2017183904A (en) * | 2016-03-29 | 2017-10-05 | セコム株式会社 | Region detection device |
| CN110312924A (en) * | 2017-02-24 | 2019-10-08 | 松下知识产权经营株式会社 | Aridity sensor |
| CN114537425A (en) * | 2022-02-28 | 2022-05-27 | 重庆长安汽车股份有限公司 | Detection early warning method and device for front deceleration strip and ditch bank during driving and vehicle |
| CN114537425B (en) * | 2022-02-28 | 2024-05-24 | 重庆长安汽车股份有限公司 | Detection and early warning method and device for front deceleration strip and ditch during driving and vehicle |
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