JP2010236932A - Fallout detection device - Google Patents

Fallout detection device Download PDF

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JP2010236932A
JP2010236932A JP2009083206A JP2009083206A JP2010236932A JP 2010236932 A JP2010236932 A JP 2010236932A JP 2009083206 A JP2009083206 A JP 2009083206A JP 2009083206 A JP2009083206 A JP 2009083206A JP 2010236932 A JP2010236932 A JP 2010236932A
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camera
background plate
circuit
signal
output
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JP5475309B2 (en
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Yasukazu Sano
安一 佐野
Yoshiyuki Ito
喜之 伊藤
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Nihon Dennetsu Co Ltd
Institute of National Colleges of Technologies Japan
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Nihon Dennetsu Co Ltd
Institute of National Colleges of Technologies Japan
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Abstract

<P>PROBLEM TO BE SOLVED: To provide a fallout detection device detecting existence of a fallout by a simple structure. <P>SOLUTION: This fallout detection device includes a camera 1, a background plate 2 including a plain surface arranged oppositely to the camera, a light source 3 for illuminating the surface of the background plate 2 from the camera side, and a signal processing part for processing an output signal from the camera 1. The signal processing part includes a floating binarization circuit 4 for pulsing a reflected signal component from a fallout included in the output signal from the camera by floating binarization. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

本発明は、降雪等の降下物を検知する装置に係り、特に、降雪を検知して屋根に設置されたヒータにより受雪面を加熱することにより融雪するシステムに用いる場合に好適な降下物検出装置に関する。   The present invention relates to a device for detecting fallen objects such as snowfall, and particularly suitable for use in a system for melting snow by detecting snowfall and heating a snow receiving surface with a heater installed on a roof. Relates to the device.

従来の降雪センサの構成を図10に示す(特許文献1参照)。この動作原理を同図を用いて説明する。図10においてアーム端面には投光のための投光ファイバー端が配置されており同時に受光のための受光ファイバー端が設置されている。投光ファイバーから出た光は、投光ファイバ及び受光ファイバ端面の高さまで下方から積雪があると雪中での透過、散乱を繰返しながら受光ファイバーに届く。受光ファイバに到達した光量があれば降雪により積雪ありとして検知するものである。また別の従来技術として図11に示すようなテレビカメラを用いビデオ信号処理により画像信号から雪片信号のみを検知する方法が知られている(特許文献2参照)。なおビデオ信号の2値化回路としては浮動閾値2値化回路(以下浮動2値化回路と記す)が知られている(特許文献3参照)。この浮動2値化回路は錠剤の表面に含まれる僅かな傷・しみ検出、換言すればビデオ信号中に含まれる高周波信号を高感度に検出するのに適している。   FIG. 10 shows a configuration of a conventional snowfall sensor (see Patent Document 1). This operation principle will be described with reference to FIG. In FIG. 10, a projecting optical fiber end for projecting light is disposed on the arm end face, and at the same time, a receiving optical fiber end for receiving light is installed. The light emitted from the projecting optical fiber reaches the receiving optical fiber while repeating transmission and scattering in the snow when there is snow from below to the height of the end faces of the projecting fiber and the receiving fiber. If there is an amount of light reaching the light receiving fiber, it is detected that there is snow due to snowfall. As another conventional technique, a method of detecting only a snowflake signal from an image signal by video signal processing using a television camera as shown in FIG. 11 is known (see Patent Document 2). As a video signal binarization circuit, a floating threshold binarization circuit (hereinafter referred to as a floating binarization circuit) is known (see Patent Document 3). This floating binarization circuit is suitable for detecting a slight flaw / stain included in the surface of the tablet, in other words, for detecting a high-frequency signal included in the video signal with high sensitivity.

特開平10−10240号公報Japanese Patent Laid-Open No. 10-10240 特開2001−13265号公報JP 2001-13265 A 特公平1−24372号公報Japanese Patent Publication No. 1-24372

従来の降雪センサの1つの技術(特許文献1)である投光ファイバと受光ファイバを組み合わせ積雪により投光ファイバから出射された光が受光ファイバに到達したか否かで積雪を検知する方式は図10からも分かるように少なくもこれらファイバを納める腕(アーム)まで積雪がないと積雪を検知できなかった。すなわち積雪のない雪の降りはじめを検知できない換言すればセンサとしての感度が悪いという欠点があった。   A conventional snowfall sensor (Patent Document 1) is a technique for detecting snow accumulation based on whether or not light emitted from a light projecting fiber has reached the light receiving fiber by combining the light projecting fiber and the light receiving fiber. As can be seen from FIG. 10, the snow could not be detected unless there was snow on at least the arm that houses these fibers. In other words, there is a drawback that it is impossible to detect the start of snowfall without snow accumulation.

一方、別の従来技術であるテレビカメラを用いる方法(特許文献2)は図11に示すように回路が大変複雑である。テレビカメラ、テレビカメラ制御回路、フレーム差分画像作成回路、2値化回路、領域作成回路、形状特徴抽出回路、雪片候補抽出回路、重心算出回路、時空間距離計算回路、雪片抽出回路、雪片分布状態判定回路、降雪判定回路などのブロックに分かれておりいわゆる高度なパタン認識システムとなっている。そのためコストが高くなるという欠点があった。同時に部品点数も多くそのため信頼性に課題があった。   On the other hand, another conventional technique using a television camera (Patent Document 2) has a very complicated circuit as shown in FIG. TV camera, TV camera control circuit, frame difference image creation circuit, binarization circuit, region creation circuit, shape feature extraction circuit, snowflake candidate extraction circuit, center of gravity calculation circuit, spatio-temporal distance calculation circuit, snowflake extraction circuit, snowflake distribution state It is divided into blocks, such as a judgment circuit and a snowfall judgment circuit, and it is what is called an advanced pattern recognition system. For this reason, there is a disadvantage that the cost is increased. At the same time, the number of parts was large, so there was a problem in reliability.

そこで本発明は上記問題点を解決するものであり、簡易な構造で降下物の存在を検出することの可能な降下物検出装置を実現することにある。   Accordingly, the present invention is to solve the above-described problems and to provide a falling object detection apparatus capable of detecting the presence of a falling object with a simple structure.

本発明の降下物検出装置は、カメラと、該カメラに対向配置される無地の表面を備えた背景板と、前記カメラ側から前記背景板の前記表面を照明する光源と、前記カメラの出力信号を処理する信号処理部と、を備え、前記信号処理部は、前記カメラの前記出力信号に含まれる降下物からの反射信号成分を浮動2値化によりパルス化する浮動2値化回路を有することを特徴とする。   The falling object detection device of the present invention includes a camera, a background plate provided with a plain surface facing the camera, a light source that illuminates the surface of the background plate from the camera side, and an output signal of the camera A signal processing unit for processing the signal, and the signal processing unit includes a floating binarization circuit that pulses the reflected signal component from the fallout included in the output signal of the camera by floating binarization. It is characterized by.

この場合に、前記信号処理部は、前記浮動2値化回路の出力のパルス数を一定期間積算するカウンタと、該カウンタの出力する積算値若しくはその平均値を所定の閾値と比較する判定手段と、をさらに有することが好ましい。   In this case, the signal processing unit includes a counter that integrates the number of pulses output from the floating binarization circuit for a certain period, and a determination unit that compares the integrated value output from the counter or an average value thereof with a predetermined threshold value. It is preferable to further have.

また、前記信号処理部は、前記浮動2値化回路の出力のパルス数を一定期間積算するカウンタと、前記光源から照射された光の有無による前記カウンタの出力する積算値若しくはその平均値の差を所定の閾値と比較する判定手段と、をさらに有することが好ましい。照明光の有無による出力差が小さい場合には降下物に起因しない原因、例えば、背景板の汚れや外光のゆらぎ等で検出出力が得られているとすることで、降下物の有無や融雪用ヒータの駆動の有無等の判断をより確実に行うことができる。   The signal processing unit includes a counter that integrates the number of pulses output from the floating binarization circuit for a certain period, and a difference between an integrated value output by the counter or an average value thereof depending on the presence or absence of light emitted from the light source. It is preferable to further include determination means for comparing the value with a predetermined threshold value. If the output difference due to the presence or absence of illumination light is small, it is assumed that the detection output is obtained due to a cause that is not caused by a fallen object, such as dirt on the background plate or fluctuations in external light, etc. It is possible to more reliably determine whether or not the heater is driven.

さらに、前記背景板の表面は屏風状に屈折して構成され、前記光源から照射された光の前記背景板の表面による正反射光が直接前記カメラへ向かう方向から逸れるように構成されることが好ましい。   Further, the surface of the background plate is configured to be refracted like a folding screen, and the specularly reflected light from the surface of the background plate of the light emitted from the light source is configured to deviate directly from the direction toward the camera. preferable.

この場合において、前記背景板の表面において前記屏風状の稜線ラインあるいは谷底ラインの線幅を前記カメラの該ラインと交差する方向の分解能以下の線幅に構成することが望ましい。   In this case, it is desirable that the line width of the screen-like ridge line or valley line on the surface of the background plate is set to a line width equal to or smaller than the resolution in the direction intersecting the line of the camera.

また、前記カメラの少なくとも撮影方向前面が透明ヒータ付きガラスで構成された窓部で覆われることが好ましい。   Moreover, it is preferable that at least the front surface of the camera in the photographing direction is covered with a window portion made of glass with a transparent heater.

この場合に、前記窓部は前記透明ヒータ付きガラスに光触媒作用のあるガラスを重ねて構成され、該光触媒ガラスが外側へ露出する態様で設置されることが望ましい。   In this case, it is preferable that the window portion is formed by stacking a glass having a photocatalytic action on the glass with the transparent heater, and the photocatalyst glass is installed in a manner to be exposed to the outside.

さらに、前記カメラの焦点位置を前記背景板の表面よりもカメラ側にセットすることが好ましい。   Furthermore, it is preferable that the focal position of the camera is set closer to the camera than the surface of the background plate.

また、前記背景板は無地黒色の前記表面を備えるとともに、複数の前記光源が分散配置されることが好ましい。黒色の背景を用いることで降下物特に降雪をより検出しやすくなるとともに、背景板の表面を複数の分散配置された光源により照明することで前記背景板からの反射光量分布がより均一になるので、降下物特に降雪を安定かつ確実に検知することが可能になる。   In addition, it is preferable that the background plate has the plain black surface and a plurality of the light sources are dispersedly arranged. Using a black background makes it easier to detect falling objects, especially snowfall, and illuminates the surface of the background plate with a plurality of light sources arranged in a distributed manner, so that the amount of reflected light from the background plate becomes more uniform. This makes it possible to detect fallen objects, particularly snowfall, stably and reliably.

本発明は、従来技術による場合に比べて低コストであり高信頼性を備えかつ高感度な降下物検出装置を提供できる効果がある。   The present invention is advantageous in that it can provide a fallout detection apparatus that is low in cost, highly reliable, and highly sensitive as compared with the case of the prior art.

本発明の降下物検出装置を使用した融雪システムの構成を示す図。The figure which shows the structure of the snow melting system using the falling object detection apparatus of this invention. 本発明の降下物検出装置の浮動2値化回路のブロック図。The block diagram of the floating binarization circuit of the falling object detection apparatus of this invention. 本発明の降下物検出装置の浮動2値化回路。The floating binarization circuit of the falling object detection apparatus of this invention. 本発明の2値化回路の動作を示す図。The figure which shows operation | movement of the binarization circuit of this invention. 本発明の信号処理の動作を示す図。The figure which shows the operation | movement of the signal processing of this invention. 背景板の第2の実施例。2nd Example of a background board. 背景板を第2の実施例テレビカメラとともに示した平面図。The top view which showed the background board with the 2nd Example television camera. 背景板の第2の実施例の動作を説明するための図。The figure for demonstrating operation | movement of the 2nd Example of a background board. 本発明の降雪の判断のためのCPUのフローチャート。The flowchart of CPU for judgment of snowfall of this invention. 投受光ファイバを用いた従来の降下物検出装置を用いた融雪システムを示す図。The figure which shows the snow melting system using the conventional fallen object detection apparatus using a light projection / reception fiber. 画像処理技術を用いた従来の降下物検出装置のシステム回路ブロック図。The system circuit block diagram of the conventional falling object detection apparatus using an image processing technique.

次に、図面を参照して本発明に係る実施形態について説明する。本実施形態は、図1に示すように、撮像手段を構成するカメラ1と、このカメラ1の撮影範囲内に少なくとも一部が対向配置された背景板2と、カメラ1による撮影画像を処理する信号処理部とを備えている。   Next, an embodiment according to the present invention will be described with reference to the drawings. In this embodiment, as shown in FIG. 1, a camera 1 that constitutes an imaging unit, a background plate 2 that is at least partially opposed to the imaging range of the camera 1, and an image captured by the camera 1 are processed. And a signal processing unit.

本実施形態は、雪片を検出するための撮像手段であるカメラ1(例えば、モノクロテレビカメラ、ビデオカメラなど)と、カメラ1の画像信号の雪片以外の画像信号をほぼ一定レベルにするための無地黒色の背景板2と、背景板2に向かって投光し降雪があれば雪片からの反射信号をカメラに入射させるための近赤外光源で構成される投光器(光源)3と、投光器3(近赤外光源)を駆動するための駆動回路と、カメラ1の出力のビデオ信号に含まれる雪片信号を2値化(1または0のデジタル信号化)するための2値化回路であって該2値化回路は投光器の光源の経時変化などを考慮し所謂固定閾値ではなく浮動点である浮動2値化回路4と、この浮動2値化回路4の出力パルス信号PFを積算計数するための第1積算カウンタ5及び第2積算カウンタ6と、カメラ1から出力されるビデオ信号より垂直同期信号を分離検出するための同期信号分離回路7と、該同期信号分離検出回路7から得られる垂直同期信号を1/2の周波数に分周するものであって、Q出力とQバー出力が前記それぞれ第1積算カウンタ5及び第2積算カウンタ6の積算時間を決定しかつQ出力の立ち上がりとQバー出力の立ち上がりがそれぞれ第1積算カウンタ5及び第2積算カウンタ6をリセットするように作用する1/2分周回路8と、該1/2分周回路8のQ出力とパルス信号PFと後述の第1NAND回路9の出力とのアンドを取りその出力を第1積算カウンタ5に入力させるための第1アンド回路11と、Qバー出力パルス信号PFと後述の第2NAND回路10の出力とのアンドを取りその出力を第2積算カウンタ6に入力させるための第2アンド回路12と、第1積算カウンタ5の出力に接続されカウンタが最大計数値以上のパルスが入力されても計数値が変化しないようにするための第1NAND回路9と、第2積算カウンタ6の出力に接続されカウンタが最大計数値以上のパルスが入力されても計数値が変化しないようにするための第2NAND回路10と、これら積算カウンタの積算データ及び後述する操作スイッチ14のデータを後述する演算手段15(CPU)に入力するとともに、検出出力をヒータ駆動回路に出力する入出力回路(I/O)13と、これらの1垂直期間内に積算されたパルス数を更に所定のNA垂直期間だけ積算するためのNA値を人間が設定できるようにし、降雪の有無を決定するためのパルス数の閾値を人間が設定できるようにする閾値(デジタル値)設定用の操作スイッチ14と、上記NA値に基づき前記積算をNA垂直期間積算し該積算値が降雪の有無の判定基準NSとの比較により判断する演算手段(CPU)15と、上記検出出力によって制御され、融雪用ヒータを駆動するヒータ駆動回路と、を備えている。 In the present embodiment, a camera 1 (for example, a monochrome television camera, a video camera, or the like) that is an imaging unit for detecting snowflakes and a plain color for setting image signals other than snowflakes in the image signal of the camera 1 to a substantially constant level. A black background plate 2, a projector (light source) 3 composed of a near-infrared light source for causing a reflected signal from the snowflake to enter the camera if there is snowfall and light is projected toward the background plate 2, and a projector 3 ( A driving circuit for driving a near-infrared light source), and a binarizing circuit for binarizing a snowflake signal included in the video signal output from the camera 1 (converting into a digital signal of 1 or 0), a binarization circuit floating binarization circuit 4 is a floating-point rather than consideration of aging of the projector light source so-called fixed threshold, for accumulating counts the output pulse signals P F of the floating binarization circuit 4 First integration counter 5 and second integration The synchronizing signal separating circuit 7 for separating and detecting the vertical synchronizing signal from the video signal output from the camera 6, and the vertical synchronizing signal obtained from the synchronizing signal separating and detecting circuit 7 divided into ½ frequency. The Q output and the Q bar output determine the integration time of the first integration counter 5 and the second integration counter 6, respectively, and the rise of the Q output and the rise of the Q bar output are respectively the first integration counter. 5 and 1/2 dividing circuit 8 which acts as the second integration counter 6 is reset, the output of the 1NAND circuit 9 to be described later and the Q output and the pulse signal P F of the 1/2 frequency divider 8 a first aND circuit 11 for inputting takes and its output to the first integrating counter 5, and taken up its output second multiplication of the output of the 2NAND circuit 10 described later and the Q bar output pulse signal P F Input to counter 6 A second AND circuit 12 for connecting to the output of the first integration counter 5, a first NAND circuit 9 for preventing the count value from changing even if a pulse having a maximum count value or more is input to the counter, 2 A second NAND circuit 10 connected to the output of the integration counter 6 for preventing the count value from changing even if a pulse of the counter exceeding the maximum count value is input, integration data of these integration counters, and an operation switch 14 described later. Is input to the arithmetic means 15 (CPU) to be described later, and the input / output circuit (I / O) 13 that outputs the detection output to the heater drive circuit, and the number of pulses accumulated in one vertical period are further calculated. the N a value for integrating predetermined N a vertical period so as human-set threshold to make the number of pulses of a threshold for determining the presence or absence of snowfall can be set humans (digital value) setting An operation switch 14 of the titration, and calculating means (CPU) 15 to which the integrated value the integration based on said N A value accumulating N A vertical period is determined by comparing the criterion N S of the presence or absence of snow, the A heater drive circuit that is controlled by the detection output and drives the snow melting heater.

図9は降雪の有無判断のためのフローチャートである。図9に示すように、まず初期設定としてデータを平均するための平均化回数NAと降雪有無判断閾値NSを図1に示す操作スイッチ14(DIPコードスイッチ)により設定する。図1に示す同期信号分離検出回路7により垂直同期信号が分離出力されこの信号が同図の分周回路8により垂直同期信号の周波数の1/2の周波数であってかつHigh及びLowの時間が同一の矩形信号に変換される。浮動2値化回路から得られるパルス信号PFは分周回路8の出力Q、Qバーそれぞれと同図に示す第1AND回路11及び第2AND回路12によりANDをとって第1積算カウンタ5及び第2積算カウンタ6に入力され、これらのカウンタにより積算計数される。なおこれらのAND回路11,12の入力にはAND条件として積算カウンタが計数可能な最大値になったことを積算カウンタの出力に接続されている第1NAND回路9及び第2NAND回路10によりチェックされ、それ以上はカウントアップされないようになっている。QとQバーはそれぞれ第2積算カウンタ6及び第1積算カウンタ6のデータである積算計数値SUM1、SUM2がCPU15が読取可能なE1及びE2信号として入出力回路(I/O)13に入力されると、前記積算計数値SUM1、SUM2はCPU15で読み取られメモリに記憶される。積算計数値SUM1、SUM2をNA回測定しその和の平均値SUMAが初期設定値の降雪有無判断閾値NSと比較し大きければ降雪有、小さければ降雪なしと判断し降雪有/無信号を出力する。なお第1及び第2積算カウンタ5,6はQとQバーの立ち上がりのタイミングでリセットされる。図9に示すようにこの一連のフローは繰り返し電源が切断されるまで続けられる。図5はこれをタイムチャートで示したものである。 FIG. 9 is a flowchart for determining the presence or absence of snow. As shown in FIG. 9, first, set by the number of averaging times N A and snowfall presence determination threshold value N S for averaging the data as the initial setting operation shown in FIG. 1 switch 14 (DIP code switch). The vertical synchronizing signal is separated and output by the synchronizing signal separation detecting circuit 7 shown in FIG. 1, and this signal is half the frequency of the vertical synchronizing signal by the frequency dividing circuit 8 in FIG. It is converted into the same rectangular signal. Pulse signal P F resulting from the floating binarization circuit min output Q of the frequency divider 8, the first integration counter 5 and the taking AND by the 1AND circuit 11 and the 2AND circuit 12 shown in the figures and Q bar respectively 2 is input to the integration counter 6 and is integrated and counted by these counters. The inputs of these AND circuits 11 and 12 are checked by the first NAND circuit 9 and the second NAND circuit 10 connected to the output of the integration counter that the integration counter has reached the maximum value that can be counted as an AND condition. No more is counted up. The Q and Q bars are input / output circuits (I / O) as E 1 and E 2 signals that can be read by the CPU 15 as integrated count values SUM 1 and SUM 2 that are data of the second integration counter 6 and the first integration counter 6, respectively. When input to 13, the integrated count values SUM 1 and SUM 2 are read by the CPU 15 and stored in the memory. Integrated counts SUM 1, SUM 2 to N A measurements compared to larger if snow chromatic average SUM A of the sum is the snowfall presence determination threshold value N S of the initial set value, determines that there is no if smaller snow snowfall Yes / Outputs no signal. The first and second integration counters 5 and 6 are reset at the rising timing of Q and Q bar. As shown in FIG. 9, this series of flows is repeated until the power is turned off. FIG. 5 shows this in a time chart.

外乱光の影響を避けるため近赤外光源を消灯させた状態で降雪有/無信号は出力せずにNA回、上述のフローを繰り返し実行しここで得られる平均値SUMADと、近赤外光源を点灯させた状態で降雪有/無信号は出力せずにNA回、上述のフローを繰り返し実行しここで得られる平均値SUMAHとの差が一定値以上で降雪有、一定値以下で降雪無と判断するようにCPUのソフトを構成してもよいことは明らかである。 To avoid the influence of ambient light, with the near-infrared light source turned off, the above flow is repeated N A times without outputting a snow presence / absence signal, and the average value SUM AD obtained here and near red The above flow is repeated N A times without outputting a snow presence / absence signal when the external light source is turned on, and the difference from the average value SUM AH obtained here is a certain value or more. It is clear that the CPU software may be configured to determine that there is no snow below.

非降雪時には背景板2の表面に対応するビデオ信号が2値化される。この背景板2の表面に対応するビデオ信号は背景板2の色調に濃淡の変化が無いために近赤外光源からの照射光の強度変化に対応した変化があるだけである。すなわち背景板2上の照射強度分布は略一定になるように投光器3(近赤外光源)には分散配置された複数の発光ダイオードが用いられておりビデオ信号にはほとんど変化がなく、したがって、背景板2が無い場合に生じる背景の画像の影響を受けない。   When it is not snowing, the video signal corresponding to the surface of the background plate 2 is binarized. The video signal corresponding to the surface of the background plate 2 has only a change corresponding to the intensity change of the irradiation light from the near-infrared light source because there is no change in the color tone of the background plate 2. That is, the projector 3 (near-infrared light source) uses a plurality of light-emitting diodes dispersedly arranged so that the irradiation intensity distribution on the background plate 2 is substantially constant, and the video signal is hardly changed. It is not affected by the background image that occurs when the background plate 2 is not provided.

ビデオ信号から雪片だけの反射光がえられれば雪片に対応するパルス数がより正確にカウントできるため背景板2からの反射光は少ないほど良い。このため投光器3からの光が背景板2で正反射しカメラ1に入射しないように背景板2をつや消し黒色の仕上げにするか、あるいは図6、図7、図8に示すように背景板を屏風のようにジグザグに折り曲げて投光器からの光が正反射光として入射しないようにする。図6は屏風構造の背景板とカメラ及び赤外光源と雪片を合わせて示した斜視図であり、図7は雪片は示していないがその平面図である。図8は図7の屏風構造の背景板付近の光線の様子を示した図であって光線が屏風構造の背景板で反射されるたびに拡散しテレビカメラに光線が戻ってくるときには近赤外光源からの直接生反射光は無いことを示す図である。屏風状に折れ曲がっている稜線ライン(図8のaに相当するライン)あるいは谷の底に当たるライン(図8のbに相当するライン)の線幅は可能な限り狭くすることが望ましい。正確にはこの線幅はテレビカメラの水平方向の分解能以下にすればこの線幅から反射してくる光は無視することができる。一般に水平方向のカメラの分解能は視野の1/500程度であるので水平方向の視野が例えば35cmの場合は700μm(=35cm/500)以下の線幅に製作すればよいことが分かる。この値は屏風型の背景板を製作する上でそれほど困難な数字ではない。また更に背景板の汚れがカメラのビデオ信号として観測された際、雪片の信号と紛らわしいいのでカメラのピントを背景板とカメラのレンズの中間に合わせるようにする。これにより多少の背景板の汚れは無視される。   If the reflected light of only the snowflake is obtained from the video signal, the number of pulses corresponding to the snowflake can be counted more accurately, so the less reflected light from the background plate 2 is better. For this reason, the background plate 2 is frosted so that the light from the projector 3 is regularly reflected by the background plate 2 and is not incident on the camera 1, or the background plate is formed as shown in FIGS. 6, 7, and 8. It is bent in a zigzag like a folding screen so that the light from the projector does not enter as regular reflection light. FIG. 6 is a perspective view showing the background plate of the folding screen structure, the camera, the infrared light source, and snowflakes, and FIG. 7 is a plan view of the snowflakes, although the snowflakes are not shown. FIG. 8 is a diagram showing the state of light rays in the vicinity of the background plate having the folding screen structure shown in FIG. 7. When the light rays are reflected by the background plate having the folding screen structure and the light rays return to the TV camera, the near infrared rays are used. It is a figure which shows that there is no direct raw reflected light from a light source. It is desirable that the line width of a ridge line bent in a folding screen (a line corresponding to a in FIG. 8) or a line corresponding to the bottom of a valley (a line corresponding to b in FIG. 8) be as narrow as possible. To be precise, if the line width is less than the horizontal resolution of the TV camera, light reflected from the line width can be ignored. In general, since the resolution of the horizontal camera is about 1/500 of the field of view, it can be seen that if the horizontal field of view is 35 cm, for example, the line width should be 700 μm (= 35 cm / 500) or less. This value is not so difficult to make a folding screen-type background board. Further, when the stain on the background plate is observed as the video signal of the camera, it may be confused with the signal of the snowflake, so the camera focus is set between the background plate and the camera lens. As a result, some background stains are ignored.

次に、本実施形態の光学系について述べる。降雪センサは夜間でも動作する必要があるため夜間にも光源は点灯していなければならない。しかし人間の目に見えると不自然であり環境に調和しない。このため光源には人間の目に見えない近赤外光(波長0.7〜2.5μm)を使用することが好ましい。ここで、撮像手段であるカメラ1にはCCD(チャージカップルドデバイス)を用いる。CCDはシリコンから成り立っており近赤外光に高い感度を持っている。この意味からも近赤外光の光源を用いるのは充分に妥当である。ちなみに本実施例では降雪センサの光源には980nmの中心波長をもつ発光ダイオード(香港Optosupply社のOSIR5113A)を用いた。またカメラ1には被写体までの最短撮像距離(ピントを合わすことのできるカメラレンズから被写体までの距離)約4cmのレンズを備えた1/3インチ27万画素CCD(台湾MINTRON社のMK-0323E)を用いた。このCCDを搭載するプリント板にはレンズ周辺に前記発光ダイオードが6個配置されている。これらは直流を供給することにより点灯させた。   Next, the optical system of this embodiment will be described. Since the snowfall sensor must operate at night, the light source must be lit at night. However, it is unnatural to human eyes and does not harmonize with the environment. For this reason, it is preferable to use near-infrared light (wavelength 0.7 to 2.5 μm) that is invisible to the human eye as the light source. Here, a CCD (charge coupled device) is used for the camera 1 which is an imaging means. CCD is made of silicon and has high sensitivity to near infrared light. From this point of view, it is sufficiently appropriate to use a near infrared light source. Incidentally, in the present embodiment, a light emitting diode (OSIR5113A of Hong Kong Optosupply Co., Ltd.) having a center wavelength of 980 nm was used as the light source of the snowfall sensor. The camera 1 also has a 1 / 3-inch 270,000 pixel CCD (MK-0323E from Taiwan MINTRON) equipped with a lens with a minimum imaging distance (distance from the camera lens that can be focused to the subject) of about 4 cm. Was used. On the printed board on which this CCD is mounted, six light emitting diodes are arranged around the lens. These were lit by supplying direct current.

カメラレンズと背景板2までの距離は約20cmとした。このとき背景板2上でのカメラ1の視野は横35cm縦25cmである。このカメラ1は外部同期型ではなく内部同期型のカメラでありカメラを動作させるための駆動回路は不要である。またカメラ1はオートゲイン機能付きである。カメラ1から出力されるビデオ信号には同期信号と画像信号がミックスされている。背景板2にはつや消し黒の屏風状ではなく平面のダンボールを用いた。カメラ1から浮動2値化回路までの信号伝送ラインには特性インピーダンス75Ωの同軸ケーブルを用いた。なお本実施例に用いたカメラレンズの被写体深度は深いこともありピントは前述したようなレンズから背景板2までの距離20cmの中間に合わせるのではなく最短撮像距離の4cmの位置に合わせた。   The distance between the camera lens and the background plate 2 was about 20 cm. At this time, the field of view of the camera 1 on the background plate 2 is 35 cm wide and 25 cm long. This camera 1 is not an external synchronization type but an internal synchronization type camera, and does not require a drive circuit for operating the camera. The camera 1 has an auto gain function. The video signal output from the camera 1 is mixed with a synchronization signal and an image signal. For the background plate 2, a flat cardboard was used instead of a matte black folding screen. A coaxial cable with a characteristic impedance of 75Ω was used for the signal transmission line from the camera 1 to the floating binarization circuit. Note that since the subject depth of the camera lens used in this embodiment is deep, the focus is not adjusted to the middle of the distance of 20 cm from the lens to the background plate 2 as described above, but to the position of 4 cm of the shortest imaging distance.

図1に示すように、上記信号処理部は、上記カメラ1による撮影画像を2値化する浮動2値化回路4を備えている。以下に試作した浮動2値化回路について述べる。この浮動2値化回路は雪片を検知するために重要な作用をする。一般にビデオ信号の2値化回路には固定閾値をもった固定閾値2値化回路と、原信号を遅延させグランドに対して減衰させた信号を閾値とする浮動2値化回路とが知られている(特許文献3)。固定閾値2値化回路は簡単であるが電源変動あるいは経年による光源の光量変化に敏感であり安定した2値化信号を得るには適していない。一方浮動2値化回路は多少複雑になるがこれらの光量変化に対しては鈍感で安定した2値化信号を得るのに適している。その上で浮動2値化回路はビデオ信号の中に含まれる比較的高周波の信号を高感度に検出できる特性があることはよく知られている(特許文献3)。本発明では雪片がテレビカメラの視野の中では数多く写ることからビデオ信号としては比較的高周波のビデオ信号になることを考慮してこの浮動2値化回路を2値化回路に選んだ。   As shown in FIG. 1, the signal processing unit includes a floating binarization circuit 4 that binarizes an image captured by the camera 1. The prototype floating binarization circuit is described below. This floating binarization circuit plays an important role in detecting snowflakes. In general, there are known a fixed threshold value binarizing circuit having a fixed threshold value for a video signal binarizing circuit and a floating binarizing circuit using a signal obtained by delaying an original signal and attenuated with respect to the ground as a threshold value. (Patent Document 3). Although the fixed threshold binarization circuit is simple, it is sensitive to fluctuations in the light source due to power supply fluctuations or aging, and is not suitable for obtaining a stable binarized signal. On the other hand, although the floating binarization circuit is somewhat complicated, it is suitable for obtaining a binarized signal which is insensitive to these light quantity changes and is stable. In addition, it is well known that the floating binarization circuit has a characteristic that can detect a relatively high frequency signal contained in a video signal with high sensitivity (Patent Document 3). In the present invention, the floating binarization circuit is selected as the binarization circuit in consideration of the fact that a large number of snowflakes appear in the field of view of the TV camera, so that the video signal becomes a relatively high-frequency video signal.

図2は本発明に用いた浮動2値化回路4のブロック図である。回路は図2に示すようにテレビカメラからの信号を同軸ケーブル経由演算増幅器(アナログデバイセズ社AD818AN)で受信する。同軸ケーブルの特性インピーダンスZ1(75Ω)と浮動2値化のための遅延素子(JPC社VCD150NP)の特性インピーダンスZ2(500Ω)は異なるためインピーダンス変換が必要である。このインピーダンス変換のためと信号増幅のために上記演算増幅器を用いた。演算増幅器の入力インピーダンスは近似的に無限大と見なしえるので同軸ケーブルの終端を該同軸ケーブルの特性インピーダンスZ1(75Ω)で終端しインピーダンス整合をとる。この終端インピーダンスの両端に現れるビデオ信号VSは前記演算増幅器で増幅されたのち次段に伝送される。該演算増幅器の出力インピーダンスは近似的に零とみなせるため演算増幅器の出力に上記遅延素子の特性インピーダンスのZ2(500Ω)を接続し該インピーダンスの他端を遅延素子に接続した。遅延素子の出力端子はアースとの間に遅延素子の特性インピーダンスZ2(500Ω)をもつポテンショメータで終端した。このポテンショメータの中間タップのアース電位に対する信号V1はビデオ信号VSが前記演算増幅器により増幅された後、遅延されアースに対して減衰された信号であって遅延減衰信号と呼ぶ。更にビデオ信号VSが演算増幅器により増幅された後その出力はアースに対して1/2に減衰されるよう1/2減衰器が接続される。1/2減衰器の出力V2を減衰信号と呼ぶ。なおポテンショメータの両端の信号は遅延線でインピーダンスマッチングが取られているため演算増幅器の出力電圧の半分の値になっていることは言うまでもない。 FIG. 2 is a block diagram of the floating binarization circuit 4 used in the present invention. As shown in FIG. 2, the circuit receives a signal from a television camera by an operational amplifier (Analog Devices AD818AN) via a coaxial cable. Since the characteristic impedance Z 1 (75Ω) of the coaxial cable is different from the characteristic impedance Z 2 (500Ω) of the delay element (JPC VCD150NP) for floating binarization, impedance conversion is necessary. The operational amplifier was used for impedance conversion and signal amplification. Since the input impedance of the operational amplifier can be regarded as approximately infinite, the end of the coaxial cable is terminated with the characteristic impedance Z 1 (75Ω) of the coaxial cable to achieve impedance matching. The video signal V S appearing at both ends of this terminal impedance is amplified by the operational amplifier and then transmitted to the next stage. Since the output impedance of the operational amplifier can be regarded as approximately zero, Z 2 (500Ω) of the characteristic impedance of the delay element is connected to the output of the operational amplifier, and the other end of the impedance is connected to the delay element. The output terminal of the delay element is terminated with a potentiometer having the characteristic impedance Z 2 (500Ω) of the delay element between the delay element and the ground. The signal V 1 with respect to the ground potential of the intermediate tap of the potentiometer is a signal that is delayed and attenuated with respect to the ground after the video signal V S is amplified by the operational amplifier, and is called a delayed attenuated signal. Further, after the video signal V S is amplified by the operational amplifier, a 1/2 attenuator is connected so that its output is attenuated to 1/2 with respect to the ground. The output V 2 of the 1/2 attenuator is called an attenuation signal. Needless to say, the signals at both ends of the potentiometer are half the output voltage of the operational amplifier because the impedance matching is taken by the delay line.

信号V1とV2はシュミット回路(アナログデバイセズ社AD8561)で比較される。雪片が画像信号として捕らえられるとシュミット回路からは浮動2値化パルスPFが出力される。図4はその様子を示すタイムチャートである。同図において信号V1とV2の大小関係が雪片部分で 逆転するためにPF信号が出力されているのが分かる。また同期信号によってもV1とV2の大小関係が逆転するためにPF信号が出力される。実際の浮動2値化回路を図3に示す。 Signals V 1 and V 2 are compared in a Schmitt circuit (Analog Devices AD8561). Snowflakes floating binarization pulse P F is output from the Schmitt circuit captured as an image signal. FIG. 4 is a time chart showing the state. The P F signal to the magnitude relationship of the signals V 1 and V 2 in the figure reversed with snowflakes portion is output is seen. The magnitude relation of V 1 and V 2 are P F signal is output to reverse by a synchronization signal. An actual floating binarization circuit is shown in FIG.

浮動2値化パルスPFを用い降雪と降雪でない場合をどのように判定するかについては図1、図5及び図9を用いてすでに述べたとおりである。ここではカメラ1、投光器(赤外光源)の駆動回路、及び浮動2値化回路4を除くデジタル信号処理系について記載する。同期信号分離検出回路7には新日本無線株式会社製NJM2229を、1/2分周回路8にはテキサスインスツルメンツ社製デュアル4ビットバイナリカウンタSN74LV393A-Q1を、積算カウンタ5,6にはテキサスインスツルメンツ社製4ビットシンクロナスバイナリカウンタSN74LV163Aを、操作スイッチ14(DIPコードスイッチ)にはKEL社製KDS16-112-Fを、演算手段であるCPU(ワンチップマイクロコンピュ−タ)には株式会社ルネサステクノロジー製8ビットワンチップマイコンH8/300を用いることができる。ここで後述するように積算カウンタ5,6のパルス計数値は僅かな小雪の降雪で1分間約200万パルス程度である。従って1垂直期間では3万3千パルスとなる。余裕をみて200万パルス程度が1垂直期間の最高パルス数とすればこのSN74LV163Aを5個カスケードに接続し使用する形の 20ビット構成とすればよい。なおこの数以上のパルスが入力した場合は前記したように、積算カウンタ出力の全てのNAND条件をとりこれを図1に示すように該カウンタの入力側のAND回路の1つの入力とすることで積算カウンタはカウントアップしないようにする。図示はしていないが降雪センサの信号処理部は勿論、電源投入時に回路リセットが行われるようになっている。 How to determine if not snowfall and snow with floating binarization pulse P F is 1, it is as described previously with reference to FIGS. 5 and 9. Here, a digital signal processing system excluding the camera 1, the projector (infrared light source) drive circuit, and the floating binarization circuit 4 will be described. NJM2229 manufactured by New Japan Radio Co., Ltd. is used for the synchronization signal separation detection circuit 7, the Texas Instruments dual 4-bit binary counter SN74LV393A-Q1 is used for the 1/2 frequency divider circuit 8, and Texas Instruments is used for the integration counters 5 and 6. 4-bit synchronous binary counter SN74LV163A made by KEL, KDS16-112-F made by KEL for operation switch 14 (DIP code switch), and Renesas Technology Corp. made by CPU (one-chip microcomputer) which is a calculation means. An 8-bit one-chip microcomputer H8 / 300 can be used. Here, as will be described later, the pulse count value of the integration counters 5 and 6 is about 2 million pulses per minute with a slight snowfall. Therefore, there are 33,000 pulses in one vertical period. If the maximum number of pulses in one vertical period is about 2 million pulses with a margin, the SN74LV163A can be connected in cascade and used in a 20-bit configuration. When more than this number of pulses are input, as described above, all NAND conditions of the integrated counter output are taken and this is used as one input of the AND circuit on the input side of the counter as shown in FIG. Do not count up the total counter. Although not shown, not only the signal processing unit of the snowfall sensor but also the circuit reset is performed when the power is turned on.

直径約7mmの紙で作成した模擬雪片をカメラ視野内に約40個均等になるよう透明なプラスチック板に張り付けこの透明プラスチック板を背景板2とカメラ1の中間に配置し45cm/秒の速度でリニアモータにより往復運動させ、模擬的に雪片検出実験を行った。その結果降雪無しでかつ昼の明るさに対応するよう室内の蛍光灯を点灯させた場合は185万パルス/分(513パルス/1垂直期間)、蛍光灯を消灯した夜間二対応した実験の場合には150万パルス/分(416パルス/1垂直期間)のデータが得られた。これに対し上記模擬雪片をリニアモータで動かし降雪時を模擬した昼相当の実験では313万パルス/分(869パルス/1垂直期間)、夜間相当の実験では317万パルス/分(880パルス/1垂直期間)のデータを得ることができた。カッコ内は積算計数値の1垂直期間の平均値SUMAである。実験確認により降雪有と降雪無でこのように明らかな差が得られた。従って例えば降雪有無判断閾値NSを600パルス/1垂直期間程度に設定すれば降雪有無を判定できることが分かる。なおこのように1垂直期間に相当する平均パルス数を求めず所定のNA垂直期間の総合計パルス数で降雪の有無を判定しても良いことは自明である。 A simulated snowflake made of paper with a diameter of about 7mm is pasted on a transparent plastic plate so that it is evenly distributed in the camera's field of view. This transparent plastic plate is placed between the background plate 2 and the camera 1 at a speed of 45cm / sec. A snowflake detection experiment was performed by reciprocating motion using a linear motor. As a result, when there is no snowfall and the fluorescent lamp in the room is turned on to correspond to the daytime brightness, 1.85 million pulses / minute (513 pulses / 1 vertical period), and in the case of two experiments at night when the fluorescent lamp is turned off The data of 1.5 million pulses / minute (416 pulses / 1 vertical period) was obtained. In contrast, the simulated snow flakes were moved by a linear motor to simulate snowfall and the daytime equivalent experiment was 3.13 million pulses / minute (869 pulses / 1 vertical period), while the night equivalent experiment was 3.17 million pulses / minute (880 pulses / 1 minute). (Vertical period) data could be obtained. The parenthesized values are the average value SUM A for one vertical period of the integrated count value. As a result of experiments, it was clear that there was a clear difference between snowfall with and without snowfall. Thus, for example snowfall presence determination threshold value N S it can be seen that determination snowfall presence be set to about 600 pulses / one vertical period. Note that this way it may be determined whether the snowfall total total number of pulses given N A vertical period without determining the number average pulse corresponding to one vertical period is self-evident.

実際にはカメラ1は図1には示していないが箱にいれて屋外2に背景板とともに設置することになる。カメラ1の前面は勿論ガラスで覆い直接レンズにゴミ、雪などが付着しないようにする。特に雪が箱前面のガラスに付着すると降雪センサとしては正常な動作をしないことになる。カメラ1自身の消費電力は2.1Wであるため箱の内部の温度はある程度外気温よりも高くなる。これによりガラス前面に付着した雪は融雪する可能性もあるが、更にこれを確実にするためガラス板付近に別途ヒータを置くかあるいは透明ヒータと一体に成った透明ガラスヒータ(栄光電器株式会社製 Warm Glass)を用いても良いことは明らかである。背景板2の裏面にもヒータを配置し背景板2に雪が付着しないようにすれば降雪時の降雪検知の精度を劣化させずにすむことは言うまでも無い。更に前記Warm Glassと光触媒クリーニングガラス(日本板硝子株式会社製クリアテクト)を張り合わせ光触媒クリーニングガラスを外気に触れるように配置すれば光触媒の作用により外気に触れるガラス面は汚れにくく降雪検知の精度維持に効果がある。   Actually, the camera 1 is not shown in FIG. 1, but is placed in a box and installed outdoors 2 with a background plate. The front surface of the camera 1 is of course covered with glass so that dust, snow, etc. are not directly attached to the lens. In particular, when snow adheres to the glass on the front of the box, it does not operate normally as a snowfall sensor. Since the power consumption of the camera 1 itself is 2.1 W, the temperature inside the box is somewhat higher than the outside air temperature. As a result, there is a possibility that the snow adhering to the front surface of the glass melts, but in order to further ensure this, a separate heater is placed near the glass plate, or a transparent glass heater integrated with the transparent heater (manufactured by Sakae Photoelectric Co., Ltd.). It is clear that Warm Glass may be used. Needless to say, if the heater is also arranged on the back surface of the background plate 2 so that the snow does not adhere to the background plate 2, the accuracy of snowfall detection at the time of snowfall is not deteriorated. Furthermore, if the Warm Glass and photocatalyst cleaning glass (Cleartect made by Nippon Sheet Glass Co., Ltd.) are laminated together, the photocatalyst cleaning glass is placed in contact with the outside air. There is.

本実施形態では、以上説明したように、背景板を用い背景を単純化することにより従来術(特許文献2)のように複雑な画像処理回路を用いないので部品点数も少なく従って高い信頼性と低コスト性を兼ね備えた降下物検出装置を実現できる。例えば積算カウンタ2個を用いたため17ミリ秒の1垂直期間で積算カウンタの積算データをCPU は読み込めばよく高価な高速CPUではなく安価なワンチップマイコンでも平均化処理ができることからも特許文献2よりも低コストに降下物検出装置を実現できることは明らかである。また特許文献1のように一定の積雪がなければ検知できないものではなく降雪の開始を検知できる。すなわち特許文献1に示す方法よりも高感度な降下物検出装置を実現できる。   In the present embodiment, as described above, the background is simplified and the background is simplified so that a complicated image processing circuit as in the conventional technique (Patent Document 2) is not used, so the number of parts is small, and thus high reliability is achieved. A falling object detection device having low cost can be realized. For example, since two integration counters are used, the CPU only needs to read the integration data of the integration counter in one vertical period of 17 milliseconds, and it can be averaged by an inexpensive one-chip microcomputer instead of an expensive high-speed CPU. However, it is clear that a falling object detection device can be realized at low cost. Further, as in Patent Document 1, it is not possible to detect without a certain amount of snow, but the start of snowfall can be detected. That is, a falling object detection device with higher sensitivity than the method disclosed in Patent Document 1 can be realized.

なお、本発明は上記実施形態に限定されることなく、その技術思想の範囲内で種々変更することが可能である。たとえば、上記実施形態ではビデオカメラを用い、ビデオカメラが出力するビデオ信号を処理するようにしているが、静止画を撮影して静止画像データを出力するスチルカメラであっても同様の処理を行うことができる。   In addition, this invention is not limited to the said embodiment, A various change is possible within the range of the technical thought. For example, in the above embodiment, a video camera is used to process a video signal output from the video camera, but the same processing is performed even in a still camera that captures a still image and outputs still image data. be able to.

本発明は降雪を検知する場合の他に、降雨の観測や、火山灰の検出による活火山の活動の監視などへの利用も可能と考えられる。黄砂、花粉の監視への適用の可能性、さらには雨は雪より速く落下することから雨と雪の区分けの可能性も秘めている。いずれにしても種々の降下物を容易かつ確実に検知することが可能である。   In addition to the case of detecting snowfall, the present invention can be used for observation of rainfall and monitoring of active volcano activity by detecting volcanic ash. It has the potential to be applied to the monitoring of yellow sand and pollen, and also has the potential to separate rain and snow because rain falls faster than snow. In any case, various falling objects can be detected easily and reliably.

1 (内部同期型)カメラ
2 背景板
3 投光器(近赤外光源)
4 浮動2値化回路
5 第1積算カウンタ(積算カウンタ1)
6 第2積算カウンタ(積算カウンタ2)
7 同期信号分離検出回路
8 1/2分周回路
9 第1NAND回路(NAND回路1)
10 第2NAND回路(NAND回路2)
11 第1AND回路(AND回路1)
12 第2AND回路(AND回路2)
13 入出力回路(I/O)
14 操作スイッチ(デジタル値設定用スイッチ)
15 演算手段(CPU)
NS 降雪の有無の判定基準パルス数
NA 浮動2値化回路の出力パルス数を平均化するための1垂直期間の数
PF 浮動2値化回路の出力パルス信号
1 (Internal synchronization type) Camera 2 Background plate 3 Floodlight (near infrared light source)
4 Floating binarization circuit 5 1st integration counter (integration counter 1)
6 Second integration counter (integration counter 2)
7 Sync signal separation detection circuit 8 1/2 frequency dividing circuit 9 1st NAND circuit (NAND circuit 1)
10 Second NAND circuit (NAND circuit 2)
11 1st AND circuit (AND circuit 1)
12 Second AND circuit (AND circuit 2)
13 Input / output circuit (I / O)
14 Operation switch (Digital value setting switch)
15 Calculation means (CPU)
N S Number of reference pulses for determining whether there is snow
The number of 1 vertical period for averaging the number of output pulses of the N A floating binary circuit
The output pulse signal P F floating binary circuit

Claims (9)

カメラと、該カメラに対向配置される無地の表面を備えた背景板と、前記カメラ側から前記背景板の前記表面を照明する光源と、前記カメラの出力信号を処理する信号処理部と、を備え、
前記信号処理部は、前記カメラの前記出力信号に含まれる降下物からの反射信号成分を浮動2値化によりパルス化する浮動2値化回路を有することを特徴とする降下物検出装置。
A camera, a background plate provided with a plain surface opposed to the camera, a light source that illuminates the surface of the background plate from the camera side, and a signal processing unit that processes an output signal of the camera Prepared,
2. The falling object detection apparatus according to claim 1, wherein the signal processing unit includes a floating binarization circuit that pulsates a reflected signal component from the falling object included in the output signal of the camera by floating binarization.
前記信号処理部は、前記浮動2値化回路の出力のパルス数を一定期間積算するカウンタと、該カウンタの出力する積算値若しくはその平均値を所定の閾値と比較する判定手段と、をさらに有することを特徴とする請求項1に記載の降下物検出装置。   The signal processing unit further includes a counter that integrates the number of pulses output from the floating binarization circuit for a certain period, and a determination unit that compares the integrated value output from the counter or an average value thereof with a predetermined threshold value. The falling object detection apparatus according to claim 1, wherein 前記信号処理部は、前記浮動2値化回路の出力のパルス数を一定期間積算するカウンタと、前記光源から照射された光の有無による前記カウンタの出力する積算値若しくはその平均値の差を所定の閾値と比較する判定手段と、をさらに有することを特徴とする請求項1に記載の降下物検出装置。   The signal processing unit is configured to predetermine a difference between a counter that accumulates the number of pulses output from the floating binarization circuit for a certain period, and an integrated value output by the counter based on the presence or absence of light emitted from the light source or an average value thereof. The falling object detection apparatus according to claim 1, further comprising: a determination unit that compares the threshold value with the threshold value. 前記背景板の表面は屏風状に屈折して構成され、前記光源から照射された光の前記背景板の表面による正反射光が直接前記カメラへ向かう方向から逸れるように構成されることを特徴とする請求項1乃至3のいずれか一項に記載の降下物検出装置。   The surface of the background plate is configured to be refracted in a folding screen, and the specularly reflected light from the surface of the background plate of the light emitted from the light source is configured to deviate directly from the direction toward the camera. The falling object detection device according to any one of claims 1 to 3. 前記背景板の表面において前記屏風状の稜線ラインあるいは谷底ラインの線幅を前記カメラの該ラインと交差する方向の分解能以下の線幅に構成することを特徴とする請求項4に記載の降下物検出装置。   The fallen object according to claim 4, wherein a line width of the folding screen ridge line or valley bottom line on the surface of the background plate is set to a line width equal to or less than a resolution in a direction intersecting the line of the camera. Detection device. 前記カメラの少なくとも撮影方向前面は透明ヒータ付きガラスで構成された窓部で覆われることを特徴とする請求項1乃至5のいずれか一項に記載の降下物検出装置。   6. The falling object detection apparatus according to claim 1, wherein at least a front surface of the camera in the photographing direction is covered with a window portion made of glass with a transparent heater. 前記窓部は前記透明ヒータ付きガラスに光触媒作用のあるガラスを重ねて構成され、該光触媒ガラスが外側へ露出する態様で設置されることを特徴とする請求項6に記載の降下物検出装置。   7. The falling object detection apparatus according to claim 6, wherein the window portion is configured by stacking a glass having a photocatalytic action on the glass with a transparent heater, and the photocatalytic glass is installed in a form exposed to the outside. 前記カメラの焦点位置を前記背景板の表面よりもカメラ側にセットしたことを特徴とする請求項1乃至7のいずれか一項に記載の降下物検出装置。   The falling object detection apparatus according to any one of claims 1 to 7, wherein a focal position of the camera is set closer to the camera than a surface of the background plate. 前記背景板は無地黒色の前記表面を備えるとともに、前記背景板からの反射光量分布がより均一になるよう複数の前記光源が分散配置されることを特徴とする請求項1乃至8のいずれか一項に記載の降下物検出装置。   The said background board is provided with the said surface of a plain black, and the said several light source is distributedly arrange | positioned so that the reflected light quantity distribution from the said background board may become more uniform. The fallout detection device according to the item.
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0124372B2 (en) * 1980-06-04 1989-05-11 Fuji Electric Co Ltd
JPH03189247A (en) * 1989-12-19 1991-08-19 Toshiba Corp On-vehicle camera device for checking backward
JP2000099877A (en) * 1998-09-25 2000-04-07 Matsushita Electric Ind Co Ltd Image type vehicle detector
JP2001028043A (en) * 1999-07-14 2001-01-30 Sumitomo Electric Ind Ltd Device, system, and method for weather detection

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0124372B2 (en) * 1980-06-04 1989-05-11 Fuji Electric Co Ltd
JPH03189247A (en) * 1989-12-19 1991-08-19 Toshiba Corp On-vehicle camera device for checking backward
JP2000099877A (en) * 1998-09-25 2000-04-07 Matsushita Electric Ind Co Ltd Image type vehicle detector
JP2001028043A (en) * 1999-07-14 2001-01-30 Sumitomo Electric Ind Ltd Device, system, and method for weather detection

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
JPN6013039641; 干野将、他: '2台のカメラを用いた降雪粒子の形状と落下速度の計測' 映像情報メディア学会技術報告 第29巻第34号, 20050623, P.21-24 *

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