JP2998694B2 - Vehicle detection device - Google Patents
Vehicle detection deviceInfo
- Publication number
- JP2998694B2 JP2998694B2 JP13345497A JP13345497A JP2998694B2 JP 2998694 B2 JP2998694 B2 JP 2998694B2 JP 13345497 A JP13345497 A JP 13345497A JP 13345497 A JP13345497 A JP 13345497A JP 2998694 B2 JP2998694 B2 JP 2998694B2
- Authority
- JP
- Japan
- Prior art keywords
- light
- vehicle
- detection
- output
- receivers
- 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.)
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Description
【発明の属する技術分野】本発明は、近赤外光を用いた
光学的手段によって車両を検出する車両検知装置に関
し、特に有料道料金所ゲートにおいて通過する車両の進
入及び発進を検出する車両検知装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle detection device for detecting a vehicle by optical means using near-infrared light, and more particularly to a vehicle detection device for detecting the entry and departure of a vehicle passing through a toll gate. Related to the device.
【０００１】[0001]
【従来の技術】従来の光を用いた車両検出装置として
は、図５の如く車線３３の両側に発光ヘッド３０と受光
ヘッド３１を配置し、この間に多数の平行ビーム３２を
形成した多段式の光ビーム遮断検知方式を採用した装置
がある。この方式では、１台の車両を横から見て車体に
すき間がある場合、車両の検知出力の時間的割れを防ぐ
目的で、対向させた発光器、受光器を多数上下に重ねて
使用している。2. Description of the Related Art As a conventional vehicle detecting apparatus using light, a multi-stage type in which a light emitting head 30 and a light receiving head 31 are arranged on both sides of a lane 33 as shown in FIG. There is an apparatus that employs a light beam cutoff detection method. In this system, when there is a gap in the vehicle when one vehicle is viewed from the side, in order to prevent temporal cracking of the detection output of the vehicle, a large number of opposing light emitters and light receivers are used one above the other. I have.
【０００２】この方式は、車両のゲート通過を検出する
ものであり、車両の検出装置としては、検出精度も高
く、車両検知出力に厳密なタイミングが要求される場合
有効である。This method detects a vehicle passing through a gate, and is effective as a vehicle detecting device when detection accuracy is high and strict timing is required for vehicle detection output.
【０００３】又、他の方式としては、ガントレー上にレ
ーザレーダを多数配置して、直下方向にレーザを発射
し、その反射光を受光して距離情報を得ることによって
車両の検知を行う方式がある。（特開平８−１２４０８
１号公報）As another method, there is a method in which a large number of laser radars are arranged on a gun tray, a laser is emitted directly below, a reflected light is received, and distance information is obtained to detect a vehicle. is there. (JP-A-8-12408
No. 1)
【発明が解決しようとする課題】以上紹介した従来の技
術の第１の問題点は、多数の発光器受光器対を使用しな
ければ、車体のすき間があるときには車両検知出力の時
間的割れが生じる場合がでてくるため、多数の発光器及
び受光器の数が必要となり、その結果装置のコストがか
かることである。The first problem of the prior art introduced above is that unless a large number of light emitter / receiver pairs are used, there is a time crack in the vehicle detection output when there is a gap in the vehicle body. As a result, a large number of light emitters and light receivers are required, which results in an increase in the cost of the device.
【０００４】第２の問題点は、車両以外の物体、例えば
人、鳥、ゴミ等で、車両として検知してしまうことであ
る。その理由は、基本的に光ビームが遮断された時に検
知出力を出すため、車両であるのか、そうでないのか区
別することができないことによる。A second problem is that an object other than a vehicle, such as a person, a bird, or dust, is detected as a vehicle. The reason is that basically, since a detection output is output when the light beam is cut off, it is impossible to distinguish whether the vehicle is a vehicle or not.
【０００５】したがって、本発明の目的は、より数の少
ない発光器受光器対で、確実な車両検知を可能として装
置の小型及びローコスト化をはかるとともに、車両以外
の物体の通過に対して、検知信号を出力しない、あるい
は取消し（キャンセル）信号を出力することによって、
車両以外の誤検知を極力低減することができる車両検知
装置を提供することである。SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to reduce the size and cost of a device by enabling reliable vehicle detection with a smaller number of light-emitting and photodetector pairs, and to detect the passage of an object other than a vehicle. By not outputting a signal or outputting a cancel signal,
An object of the present invention is to provide a vehicle detection device capable of minimizing erroneous detection of a vehicle other than a vehicle.
【０００６】[0006]
【課題を解決するための手段】本発明による車両検知装
置は、車線の一方の側の上下方向に配置された少なくと
も２個の受光器と、車線を挟んで対向する位置の上下方
向に、前記複数の受光器を覆うに足る程度の発光広がり
角をもった少なくとも２個の発光器を有する発光器・受
光器群を１組として設けることを基本とし、発光器はそ
れぞれ異なる周波数で変調された近赤外光を出力し、受
光器は対向する発光器の近赤外光をそれぞれ同時に検出
する。すなわち、平行ビーム以外に傾斜角をもったビー
ムも検出するため、少数の発光器・受光器でも広い通過
エリアを監視することができる。また、基本の構成にお
いて、発光器を２個、受光器を３個とすれば、車体の通
過エリア内をより密に監視することができる。更に、車
両進行方向において前記１組とは若干離れた位置に、他
のもう１組の発光器・受光器群を有し、これら２組の遮
断検知出力を時系列的に処理する検知処理部を有し、物
体の通過速度及び概略長さを算出して、車両であるかな
いかを判断させることにより、より確かな車両検知信号
を出力することが可能となる。 SUMMARY OF THE INVENTION A vehicle detecting device according to the present invention is provided.
At least one side of the lane
Also above and below the two opposing receivers at opposite positions across the lane
The light emission spread enough to cover the plurality of light receivers
Emitter / receiver having at least two angled emitters
Basically, an optical device group is provided as one set.
Outputs near-infrared light modulated at different frequencies.
Optical device simultaneously detects near-infrared light from opposing light emitters
I do. That is, a beam with an inclination angle other than a parallel beam
System, so even a small number of light emitters and receivers can pass through a wide area
Area can be monitored. Also, the basic configuration
If two light emitters and three light receivers are used,
The inside of the excess area can be monitored more closely. Furthermore, cars
At a position slightly apart from the one pair in both traveling directions,
It has another set of emitter and receiver, and these two sets
A detection processing unit that processes the disconnection detection output in time series
Calculate the passing speed and approximate length of the body,
More reliable vehicle detection signal by letting you judge
Can be output.
【０００７】[0007]
【０００８】[0008]
【発明の実施の形態】次に本発明の実施の形態について
図面を参照して詳細に説明する。図１を参照すると、本
発明の実施の形態は以下のとおりである。Embodiments of the present invention will now be described in detail with reference to the drawings. Referring to FIG. 1, an embodiment of the present invention is as follows.
【０００９】全体的な構成として、車線１０の一方の側
に、発光器１１，１２を上下に配置し、これらから近赤
外変調光を出力する発光部１と、車線１０の他方の側
に、発光器１１，１２からの変調光６，７を受光する受
光器１３，１４を上下に配置した受光部２との組と、更
に、この組から離れた位置に、発光器１５，１６を上下
に配置し、これから近赤外変調光を出力する発光部３
と、発光器１５，１６からの変調光８，９を受光する受
光器１７，１８を上下に配置した受光部４との組が設置
されている。As a whole configuration, light emitters 11 and 12 are vertically arranged on one side of a lane 10, and a light emitting unit 1 for outputting near-infrared modulated light therefrom, and a light emitting unit 1 on the other side of the lane 10. And a light receiving unit 2 in which light receiving units 13 and 14 for receiving the modulated lights 6 and 7 from the light emitting units 11 and 12 are vertically arranged, and further, the light emitting units 15 and 16 are disposed at positions away from the pair. Light emitting unit 3 arranged vertically and outputting near-infrared modulated light from now on
And a light receiving unit 4 in which light receiving units 17 and 18 for receiving the modulated lights 8 and 9 from the light emitting units 15 and 16 are arranged vertically.
【００１０】発光部１の発光器１１，１２は、あらかじ
め設定された周波数ｆ1 ，ｆ2 で変調された近赤外光を
出力し、受光部２の受光器１３，１４は、ｆ1 ，ｆ2 の
変調光を検出する。同様に、受光部４の受光器１７，１
８は、対向する発光部３内の発光器１５，１６から周波
数ｆ3 ，ｆ4 で変調された変調光８，９を検出する。The light emitting units 11 and 12 of the light emitting unit 1 output near-infrared light modulated at preset frequencies f1 and f2, and the light receiving units 13 and 14 of the light receiving unit 2 modulate f1 and f2. Detect light. Similarly, the light receivers 17 and 1 of the light receiver 4
Numeral 8 detects the modulated lights 8, 9 modulated at the frequencies f3, f4 from the light emitters 15, 16 in the opposing light emitting section 3.
【００１１】更に図１の構成においては、受光部２及び
受光部４からの遮断検知信号を受けて時系列的に処理
し、車両検知信号を生成する検知処理部５を有してい
る。Further, the configuration shown in FIG. 1 has a detection processing unit 5 that receives a shutoff detection signal from the light receiving unit 2 and the light receiving unit 4 and processes it in a time series to generate a vehicle detection signal.
【００１２】次に本発明の実施の形態の動作について図
１及びタイミングチャートを示した図２を参照して詳細
に説明する。受光器１３は、変調光６及び変調光７を同
時に検出する。受光器１４も同様である。従って２対の
発光器・受光器によって４本のビームを検出することが
でき、エリアの監視領域を広くとれるようにしている。
受光器１３，１４の遮断検知信号はオア出力として受光
部２から出力され、進入側遮断検知信号１９として検知
処理部５に入力される。即ち、変調光６，７のどちらか
が遮断されると進入側遮断検知信号１９がオンとなる。
同様に、変調光８，９の遮断検知信号は、受光部４の出
力としてまとめられ、脱出側遮断検知信号２０として検
知処理部５に入力される。車両が進入してきた場合、進
入側遮断検知信号１９がまずオンとなり、車両が進むに
つれて、脱出側遮断検知信号２０がオンとなる。Next, the operation of the embodiment of the present invention will be described in detail with reference to FIG. 1 and FIG. 2 showing a timing chart. The light receiver 13 detects the modulated light 6 and the modulated light 7 simultaneously. The same applies to the light receiver 14. Therefore, four beams can be detected by two pairs of light emitters and light receivers, so that the area to be monitored can be widened.
The cutoff detection signals of the light receivers 13 and 14 are output from the light receiving unit 2 as an OR output, and are input to the detection processing unit 5 as the entry side cutoff detection signal 19. That is, when either of the modulated lights 6 and 7 is cut off, the entry side cutoff detection signal 19 is turned on.
Similarly, the cutoff detection signals of the modulated lights 8 and 9 are combined as the output of the light receiving unit 4 and input to the detection processing unit 5 as the escape side cutoff detection signal 20. When the vehicle enters, the entry-side cutoff detection signal 19 is first turned on, and as the vehicle advances, the escape-side cutoff detection signal 20 is turned on.
【００１３】検知処理部５ではこれらの信号のタイミン
グ差ｔ1 と、受光部２と受光部４の車両進行軸上の距離
Ｒから車速ｖが計算される（ｖ＝Ｒ／ｔ1 ）。また検知
オン期間ｔ2 と車速ｖから車両長Ｌが計算される（Ｌ＝
ｖｔ2 ）。検知処理部５は、進入側に続いて脱出側がオ
ンとなった時、車両検知出力をオンとし、両方がオフと
なった時、車両検知出力をオフとする。The detection processing unit 5 calculates the vehicle speed v from the timing difference t1 of these signals and the distance R between the light receiving unit 2 and the light receiving unit 4 on the vehicle traveling axis (v = R / t1). The vehicle length L is calculated from the detection ON period t2 and the vehicle speed v (L =
vt2). The detection processing unit 5 turns on the vehicle detection output when the exit side is turned on following the entry side, and turns off the vehicle detection output when both are turned off.
【００１４】ここで先に計算された車両長Ｌが通常の車
両よりも明らかに短い時には、取消し（キャンセル）信
号を出力する。車両検知出力のリアルタイム性がさほど
要求されない場合には、車両検知出力を遅延し、車両判
定条件に合致しない時は出力不可とすることも可能であ
る。また、算出された車速を用いて一定長さ分だけ検知
出力の引延し処理も可能であり、検知出力の割れをうめ
て、検知割れを防ぐ効果も期待できる。If the previously calculated vehicle length L is clearly shorter than that of a normal vehicle, a cancel signal is output. If the real-time property of the vehicle detection output is not so required, the vehicle detection output may be delayed, and if the vehicle detection output does not meet the vehicle determination condition, the output may be disabled. Further, the detection output can be extended for a certain length using the calculated vehicle speed, and the effect of preventing the detection crack from being cracked in the detection output can be expected.
【００１５】図３は本発明による車両検知のフローチャ
ートを示す図であり、同図を参照すると、車両検知処理
は以下の如くなる。処理はある決まった時間で常にルー
プされる。車両が進行してくるとまず進入側検知信号
（Ｆ＿ＩＮ）がオンとなる。脱出側は未だ車両が到達し
ていないためここで一度ループを抜ける。脱出側まで車
両が進行してくると脱出側検知信号（Ｆ＿ＯＵＴ）がオ
ンとなる。このとき進入側と脱出側それぞれのカウンタ
値（Ｃ＿ＩＮとＣ＿ＯＵＴ）の差（時間差に等しい）
と、進入側ビームと脱出側ビームの距離（固定値）から
車両の速度が計算される。ここで車両検知出力される。
その後進入側検知信号及び脱出側検知信号が同時にオフ
となるまで車両検知信号は出力される。同時にオフとな
った時点が車両の通過時点であるから、ここで脱出側検
知信号持続時間と先に求めた車両速度から車両長が算出
される。この車両長が規定値より短い場合は、車両でな
いと見なし、キャンセル信号を続いて出力する。同時に
パラメータをリセットし、初期の状態に戻る。FIG. 3 is a diagram showing a flowchart of vehicle detection according to the present invention. Referring to FIG. 3, the vehicle detection processing is as follows. Processing is always looped at a fixed time. As the vehicle advances, the approach detection signal (F_IN) is first turned on. The escape side once exits the loop here because the vehicle has not yet arrived. When the vehicle advances to the escape side, the escape side detection signal (F_OUT) turns on. At this time, the difference (equal to the time difference) between the counter values (C_IN and C_OUT) of the entry side and the exit side, respectively.
Then, the speed of the vehicle is calculated from the distance (fixed value) between the entry side beam and the exit side beam. Here, the vehicle is detected and output.
Thereafter, the vehicle detection signal is output until the entry side detection signal and the exit side detection signal are simultaneously turned off. Since the time when the vehicle is simultaneously turned off is the time when the vehicle passes, the vehicle length is calculated from the duration of the escape side detection signal and the vehicle speed obtained previously. If the vehicle length is shorter than the specified value, it is determined that the vehicle is not a vehicle, and a cancel signal is subsequently output. At the same time, reset the parameters and return to the initial state.
【００１６】次に、本発明の第２の実施の形態について
図４を参照して説明する。第２の実施の形態は、発光部
２１の中に、２個の発光器２３，２４を有し、受光部２
２の中に３個の受光器２５，２６，２７を有している。
即ち、第１の実施の形態で車体のすき間による検知割れ
が発生する場合、第２の実施の形態のように受光器を１
個追加するだけで、検知対象ビームが２本増えることに
なり、車両の通過エリア内をより密に監視することがで
きる。本方式において一般にｍ個の発光器とｎ個の受光
器を用いれば、最大ｍ×ｎ本のビームを検出できること
になる。Next, a second embodiment of the present invention will be described with reference to FIG. In the second embodiment, the light emitting unit 21 includes two light emitting units 23 and 24,
2 has three light receivers 25, 26, 27.
That is, when the detection crack occurs due to the gap of the vehicle body in the first embodiment, the light receiver is set to one as in the second embodiment.
Only by adding the number of detection target beams, the number of detection target beams increases by two, and the inside of the vehicle passing area can be monitored more closely. In general, if m light emitters and n light receivers are used in this method, m × n maximum beams can be detected.
【００１７】[0017]
【発明の効果】本発明の第１の効果は、より少ない発光
器・受光器によって車両の検知出力割れを防ぐことがで
き、装置の小型・ローコスト化をはかることができるよ
うになるということである。その理由は、平行ビームだ
けでなく、傾斜角をもったビームも同時に監視すること
により、平行多段式よりも通過エリアの監視効率が高ま
るからである。The first effect of the present invention is that the detection output of the vehicle can be prevented from cracking with a smaller number of light emitters and light receivers, and the device can be reduced in size and cost. is there. The reason is that not only the parallel beam but also the beam having the inclination angle is monitored at the same time, so that the efficiency of monitoring the passing area is higher than that of the parallel multistage type.
【００１８】第２の効果は、車両の検知精度が向上する
ことである。その理由は、物体の通過速度及び車両長を
算出することによって車両以外の物体による誤検出を軽
減することができるからである。A second effect is that the detection accuracy of the vehicle is improved. The reason is that by calculating the passing speed of the object and the vehicle length, erroneous detection by an object other than the vehicle can be reduced.
【図１】本発明の車両検知装置の一実施の形態を示す全
体斜視図である。FIG. 1 is an overall perspective view showing one embodiment of a vehicle detection device of the present invention.
【図２】図１の実施の形態例の動作を示すタイミングチ
ャートである。FIG. 2 is a timing chart showing the operation of the embodiment of FIG.
【図３】本発明による車両検知処理を示すフローチャー
トである。FIG. 3 is a flowchart showing a vehicle detection process according to the present invention.
【図４】本発明の他の実施の形態を示す図である。FIG. 4 is a diagram showing another embodiment of the present invention.
【図５】従来の車両検知器を示す斜視図である。FIG. 5 is a perspective view showing a conventional vehicle detector.
１，３，２１ 発光部 ２，４，２２ 受光部 ５ 検知処理部 ６，７，８，９，２８，２９ 変調光 １０，３３ 車線 １１，１２，１５，１６，２３，２４ 発光器 １３，１４，１７，１８，２５，２６，２７ 受光器 １９ 進入側遮断信号 ２０ 脱出側遮断信号 ３０ 発光ヘッド ３１ 受光ヘッド ３２ 光ビーム 1,3,21 Light-emitting unit 2,4,22 Light-receiving unit 5 Detection processing unit 6,7,8,9,28,29 Modulated light 10,33 Lane 11,12,15,16,23,24 Light-emitting device 13, 14, 17, 18, 25, 26, 27 Light receiver 19 Ingress-side cutoff signal 20 Escape-side cutoff signal 30 Light emitting head 31 Light receiving head 32 Light beam
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) G08G 1/00 - 1/16 ──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. 7 , DB name) G08G 1/00-1/16
Claims (3)
器を覆う発光広がり角をもった複数の光発生器とを有
し、発光器と受光器の間を通過する車両により光が少な
くとも１本遮断された場合に検知出力を発生する車両検
知装置において、前記複数の発光器が互いに異なる変調
光を発生することを特徴とする車両検知装置。1. A method comprising: a plurality of light receivers arranged in a vertical direction; and a plurality of light generators each having an emission divergence angle covering the plurality of light receivers at positions facing each other across a lane, In a vehicle detection device that generates a detection output when at least one light is blocked by a vehicle passing between a light emitter and a light receiver, the plurality of light emitters are different from each other.
A vehicle detection device that generates light .
器を覆う発光広がり角をもった複数の光発生器とを有
し、発光器と受光器の間を通過する車両により光が少な
くとも１本遮断された場合に検知出力を発生する車両検
知装置において、前記複数の発光器が２個の発光器であ
り、前記複数の受光器が３個の受光器である ことを特徴
とする車両検知装置。2. A plurality of light receivers arranged vertically and a plurality of light receivers respectively opposed to each other across a lane.
Multiple light generators with emission divergence angle
And the vehicle passing between the emitter and the receiver has less light
A vehicle inspection that generates a detection output when at least one
In the sensing device, the plurality of light emitters are two light emitters.
Wherein the plurality of light receivers are three light receivers .
線を挟んで対向する位置にそれぞれが前記複数の受光器
を覆う発光広がり角をもった複数の光発生器とを有し、
発光器と受光器の間を通過する車両により光が少なくと
も１本遮断された場合に検知出力を発生する組み合わせ
を、車両進行軸上離れた位置に２組有し、前記２組の検
知出力を受けて時系列的処理によって車両の通過速度及
び車両長を算出し、もって車両検知出力を出力する検知
処理部を有する車両検知装置において、前記検知処理部
が算出された車両長があらかじめ定めた長さより短いと
き、この出力をキャンセルすることを特徴とする車両検
知装置。3. A plurality of light receivers and a vehicle arranged vertically.
Each of the plurality of light receivers is located at a position facing each other with the line interposed therebetween.
A plurality of light generators having an emission spread angle that covers
The vehicle passing between the emitter and the receiver reduces the light
Combination that generates a detection output when one is shut off
At two positions separated from each other on the vehicle traveling axis.
With the knowledge output, the vehicle passing speed and
Detection that calculates the vehicle detection length and the vehicle detection output
In a vehicle detection device having a processing unit, the detection processing unit
If the calculated vehicle length is shorter than the predetermined length
A vehicle detection device for canceling the output .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13345497A JP2998694B2 (en) | 1997-05-23 | 1997-05-23 | Vehicle detection device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13345497A JP2998694B2 (en) | 1997-05-23 | 1997-05-23 | Vehicle detection device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH10326399A JPH10326399A (en) | 1998-12-08 |
| JP2998694B2 true JP2998694B2 (en) | 2000-01-11 |
Family
ID=15105167
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13345497A Expired - Fee Related JP2998694B2 (en) | 1997-05-23 | 1997-05-23 | Vehicle detection device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2998694B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4705259B2 (en) * | 2001-03-27 | 2011-06-22 | クラリオン株式会社 | Road information processing apparatus, method, road information processing software, navigation system and method, and road information database creation method |
| NZ529947A (en) | 2001-06-04 | 2005-08-26 | Ceos Ind Pty Ltd | A monitoring process and system |
-
1997
- 1997-05-23 JP JP13345497A patent/JP2998694B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH10326399A (en) | 1998-12-08 |
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