JP2005024284A

JP2005024284A - Painted surface inspection device for vehicle

Info

Publication number: JP2005024284A
Application number: JP2003187070A
Authority: JP
Inventors: Yasunori Yamagishi; 靖則山岸
Original assignee: Kanto Jidosha Kogyo KK; Kanto Auto Works Ltd
Current assignee: Kanto Jidosha Kogyo KK; Toyota Motor East Japan Inc
Priority date: 2003-06-30
Filing date: 2003-06-30
Publication date: 2005-01-27
Anticipated expiration: 2023-06-30
Also published as: JP4274862B2

Abstract

<P>PROBLEM TO BE SOLVED: To save a space necessary for inspecting in particular a painted surface on the vehicle side, concerning a painted surface inspection device for a vehicle equipped with a surface light emitting body 20 for irradiating the painted surface 1a of the vehicle flatly with light and CCD cameras 10 for inputting regularly reflected light by the painted surface 1a irradiated with the light, for inspecting the painted surface 1a by processing an image signal from the CCD cameras. <P>SOLUTION: The surface light emitting body 20 is arranged on the side of a conveyance route to irradiate the painted surface 1a of the vehicle side with the light horizontally from the oblique direction, and the CCD cameras 10 are arranged adjacently to the opposite conveyance route side of the surface light emitting body 20, and a mirror 30 for inputting regularly reflected light by the painted surface 1a irradiated with the light and sending the reflected light to the CCD cameras 10 is arranged on the separated position along the conveyance route relative to the CCD cameras 10. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、車両の塗面を面状に光照射する面照射体と、搬送路に沿って搬入されてきた車両の塗面に対して、光照射された塗面での正反射光を入射させるイメージセンサとを備え、このイメージセンサの画像信号を処理して塗面を検査するようになった車両用塗面検査装置に関するものである。
【０００２】
【従来の技術】
特許文献１によれば、図６に示すように、平行光で面照射する面照射体７と、この面照射体に間隔を置いて側方へ配置されたイメージセンサ６とを備え、正反射光が入射するように前方位置で互いの中心光軸が交差するようにそれぞれ配向されている撮像装置９をロボット５のアーム先端部に取付けて、車両１の塗面に対する撮像装置９の三次元位置及び姿勢を制御しつつ塗面を走査することにより、イメージセンサ６から出力される画像信号レベルが、正常塗面に対応する高信号レベルから低下するのを検出して車両１の塗面に生じている微小欠陥を自動的に検知する車両用塗面検査装置が開示されている。
【０００３】
また、特許文献２によれば、車両等の塗面に明暗パターンを映し出すように面照射する面照射体と、塗面を撮像して得られる明暗パターンの受光画像を画像データに変換するように、互いの中心光軸が交差するように配向されたイメージセンサとを備え、画像データから明暗パターンの明部と暗部の境界領域を抽出し、その明暗境界領域の画像を所定のしきい値で２値化し、その２値化画像の明暗境界領域の幅のばらつき度合に応じて塗面の平滑性を判定する塗膜平滑性検査装置が周知である。
【０００４】
【特許文献１】
特開２００１−１３３４０９号公報
【特許文献２】
特開平９−１２６７４４号公報
【０００５】
【発明が解決しようとする課題】
しかしながら、このような面照射体とイメージセンサとを間隔を置いて両側に配置された撮像装置をロボットアームの先端部に取付けて、搬入してくる車両の上面に加えて、側面も走査しようとすると、ロボット自体の構造が大型になるだけでなく、側面領域にこれらの動作スペースを用意する必要があり、占有スペースも広くなる問題がある。
【０００６】
そこで、本出願人は、特願２００３−１３１４４４により、面照射体及びイメージセンサが、搬送路の側方に水平に配置されたアームの両側の端部にそれぞれ取付けられると共に、アームをその縦方向の水平回転軸線を中心に回転させる回転駆動部と、アームをその中間位置で垂直回転軸線を中心に水平面で旋回させる旋回駆動部とを備え、所定の検査領域の三次元形状データに応じて、正反射光をイメージセンサへ入射させるように、アームの回転角及び旋回角を制御する車両用塗面検査装置を提案した。
【０００７】
これにより、構造的に大きなロボットを用いることなく、搬送路の側方の占有面積も狭くした状態で車両の塗面検査が可能となるが、この車両用塗面検査装置も特許文献１及び特許文献２の装置と同様に面照射体と、イメージセンサとを搬送路に沿って互いに離間させて配置し、それぞれの中心光軸を前方の塗面で交差させて、光照射された塗面での正反射光をイメージセンサに入射させることを前提にしている。したがって、イメージセンサの塗面までの離間距離は、結像に要する最短対物距離に対応して設定される必要がある。
【０００８】
本発明は、このような点に鑑みて、特に車両側面の塗面を検査するために必要なスペースを一層節約できる車両用塗面検査装置を提供することを目的とする。
【０００９】
【課題を解決するための手段】
本発明は、この目的を達成するために、請求項１により、車両の塗面を面状に光照射する面照射体と、搬送路に沿って搬入されてきた車両の塗面に対して、光照射された塗面での正反射光を入射させるイメージセンサとを備え、このイメージセンサの画像信号を処理して塗面を検査するようになった車両用塗面検査装置において、面照射体が、車両側面の塗面を水平に斜め方向から光照射するように、搬送路の側方に配置されると共に、イメージセンサが面照射体の反搬送路側に隣合せに配置され、イメージセンサに対して搬送路に沿って離間した位置に、光照射された塗面での正反射光が入射し、かつその反射光をイメージセンサに入射させる光反射体が配置されたことを特徴とする。
【００１０】
面照射体で光照射された塗面での正反射光は、搬送路に対して直交方向の本来の所要の最短距離よりも接近して配置されたイメージセンサに、ミラー、プリズム等の光反射体を経由して入射することにより、所要の最短対物距離が実質上確保される。
【００１１】
基準位置での平坦な基準塗面からのずれに対応して反射光をイメージセンサに確実に入射させるには、請求項２により、光反射体が、垂直回転軸線を中心に回転可能に支持されると共に、塗面の位置又は曲面形状に応じて光反射体の回転位置を制御する回転駆動部を備えるか、又は請求項３により、光反射体を垂直回転軸線を中心に回転可能に支持するスライダが、搬送路に対して離接方向にスライド可能にガイドレールにガイドされると共に、塗面の位置又は曲面形状に応じてスライド位置を制御するスライド駆動部を備えるようにする。その際、複数個のイメージセンサで塗面の検査領域を分担する場合には、請求項４により、塗面の検査領域を分担するように、複数個のイメージセンサが上下方向へ配列されると共に、回転駆動部が、複数個の前記イメージセンサの順に撮像する撮像走査に同期し、かつ分担する検査領域の位置又は曲面形状に応じて１個の光反射体の回転位置を順に制御するか、又は請求項５により塗面の検査領域を分担するように、複数個のイメージセンサ及び複数個の光反射体が上下方向へ配列されると共に、回転駆動部が、分担する前記検査領域の位置又は曲面形状に応じて各前記光反射体の回転位置をそれぞれ制御する。基準位置での平坦な基準塗面からのずれに対応して反射光をイメージセンサに確実、かつ高感度で入射させるには、請求項６により、イメージセンサの先端部が垂直回転軸線を中心に回転可能に支持されると共に、光反射体の移動に連動してイメージセンサの回転位置を制御する回転駆動部を備えるようにする。
【００１２】
【発明の実施の形態】
図１乃至図３を基に本発明の実施の形態の一例による車両用塗面検査装置を説明する。車両側面の塗面１ａに対する撮像装置が、支柱１１にブラケット２１で取付けられ、かつ面照射体として例えば直管形蛍光灯を光源に用いて所定範囲を平行光線で照射する１個の面発光体２０と、支柱１１に取付けられた支持アーム１２に支持されたモータ利用の回転駆動部１５の垂直方向のシャフト１７に先端部が支持され、かつ検査領域を分担する上下方向に３段のイメージセンサとしてのＣＣＤカメラ１０と、搬送路に沿って離間した支柱３１に支持されたヒンジブラケット３２にピン３３で回転自在に支持された光反射体としての回転駆動部３４付きの１個のミラー３０とで構成されている。回転駆動部３４は、ロッド３６を進退駆動するモータ利用のリニアアクチュエータ３５を用い、その先端部にリンクアーム３７がピン３７ａで枢着され、その他端はミラー３０の裏面にピン３７ｂで枢着され、ロッド３６の進退によりミラー３０を回転駆動する。
【００１３】
ＣＣＤカメラ１０は、その焦点距離に対応して鮮明に結像させ得る塗面１ａに対する最短対物距離を最短で１ｍ程度とすると、従来では面発光体２０及びＣＣＤカメラ１０は、それぞれの中心光軸を所定の前方の塗面１ａで互いに同じ傾斜角で交差するように、塗面１ａに対する面直方向の離間距離は６０〜７０ｃｍになるが、本発明では面発光体２０の先端部分の面直方向の離間距離は例えば３５ｃｍ程度に設定されると共に、ＣＣＤカメラ１０は面発光体２０の反搬送路側に隣合せにミラー３０に向けて配置され、塗面１ａからミラー３０を経由してＣＣＤカメラ１０に達する入射経路が最低で１ｍ程度は確保し得るように設定されている。
【００１４】
撮像装置に対して搬送路の上流側には、車両側面の塗面１ａの三次元形状を非接触式に計測する三次元形状計測器４０が、３段の撮像装置のそれぞれの分担範囲を計測するように、支柱４１に上下方向に３段に間隔を置いて取付けられている。この三次元形状計測器は、搬送路に対して離間距離３５ｃｍ程度であり、レーザビームを発射して塗面１ａを面走査し、三角測量の原理を基に塗面の反射レーザ光の入射位置及び走査角度を基に三次元位置を解析することにより、三次元形状が計測される。その外、光学式に非接触状態で三次元形状を三次元位置データを基に計測する装置として、種々の方式のものが汎用されている。
【００１５】
このような側面用の塗面検査装置は、搬送路の反対側の側面領域にも配置されると共に、上面の塗面を検査するように撮像装置をアーム先端部に取付けて塗面を走査するロボットも設置されている。
【００１６】
図２に示すように、双方の回転駆動部１５、３４には、ミラー３０及びＣＣＤカメラ１０の回転角の制御により、塗面１ａの所定の検査領域での正反射光をＣＣＤカメラ１０へその中心光軸に平行に入射させるように、ミラー用及びＣＣＤカメラ用回転角制御信号を車両搬送に同期して逐次出力する上段、中段及び下段用の制御手段４４、４４ａ、４４ｂが付属している。３個の三次元形状計測器４０には、塗面１ａの所定の検査領域の面形状を車両搬送に同期して逐次計測し、その中心部の３次元位置に対して面直になる法線を解析して、逐次法線データを出力する上段、中段及び下段用の法線解析手段４３、４３ａ、４３ｂが付属している。
【００１７】
即ち、この法線解析手段は、例えば２０平方ｃｍ程度の検査領域ごとに面計測を行うように、車両の搬入位置に同期し、かつ１個のミラー３０が３段階に制御されるのに伴って僅かづつ順に遅延して逐次制御盤から供給される計測指令信号に応答して、逐次解析結果を出力する。制御手段４４、４４ａ、４４ｂは、入力した所属の中心部の３次元位置での法線データに対する正反射光の反射方向を解析して、各検査領域の中心部の正反射光をＣＣＤカメラ１０へその中心光軸に平行に入射させるＣＣＤカメラ１０及びミラー３０の回転角を解析すると共に、搬送速度に対応して所定時間だけ所属の計測指令信号から遅延した撮像指令信号が制御盤から逐次供給されるのに応答して、解析された回転角制御信号を出力すると共に、その直後に撮像領域が所属の計測領域に合致するタイミングで撮像を行わせる。
【００１８】
画像処理装置４５は、特許文献１として説明したように、ＣＣＤカメラ１０により撮像した画像信号レベルが、正常塗面に対応する高信号レベルから所定量低下するか否かを判断して微小欠陥位置を検知する。表示データ作成手段４６は、車両１をグラフィックデータを作成すると共に、供給された両側及び上面の塗面の画像処理データをグラフィック処理することにより、車両の画像に重ねて微小欠陥位置を指示するグラフィックデータを作成し、画像表示装置に表示させたり或はプリンタにプリントアウトさせる。
【００１９】
このように構成された車両用塗面検査装置の動作を図３を参照して説明する。車両１が三次元形状計測器４０の対面位置に搬入されてくると、２０平方ｃｍ程度の塗面１ａの所定の検査領域が３段に順に僅かな遅延時間を伴って、逐次搬送方向へ２０ｃｍ程度づつシフトするごとに計測され、その都度計測された検査領域の中心部の法線がその三次元位置の面形状を基に解析される。ミラー３０及び上段のＣＣＤカメラ１０は、上段の三次元形状計測器４０の所定の検査領域の法線データに対応してミラー３０の反射光がＣＣＤカメラ１０に面直に入射するように解析された回転角に応じて回転位置を制御されることにより、常時一定の照射角度の照射光に対する正反射光の反射光が、実線で示すように、面発光体２０の照射角度よりも浅くなった入射角でＣＣＤカメラ１０に入射する。
【００２０】
次いで、中段及び下段の三次元形状計測器４０の計測結果に応じて搬送速度よりも十分高速でミラー３０及び中、下段のＣＣＤカメラ１０の回転位置が順に制御されて撮像が行われる。このような上下方向の撮像走査が、搬送方向へ繰返され、各検査領域の画像信号が処理され、反対側の側面及び上面の塗面の画像処理データと併せて、車両１の検査結果がグラフィック表示されてモニタ、或はプリンタに出力可能となる。
【００２１】
同図Ａの点線で示すように塗面１ａが車両前後方向で曲面になったり、或は同図Ｂの点線で示すように所定の離間距離から離れた場合、所属の法線データの変化に対応して相応にミラー３０及びＣＣＤカメラ１０の回転位置が制御される。法線の基準になる中心部の三次元位置の周辺で面形状が多少変化しても面発光体２０から照射される平行光線の僅かな拡散により検査は可能である。回転制御は水平面で行われるが、垂直方向へ僅かにわん曲しても同様に検査は可能である。
【００２２】
尚、ミラー３０及びＣＣＤカメラ１０の回転位置の制御は、車両の形状に対応してティーチングしておくことも可能であるが、前述のように、三次元形状計測器４０を用意してその計測データで回転位置を制御することにより、車両の搬送路への搭載位置が正規の位置からずれることに起因する検査結果の誤差発生を回避できる。さらに、光反射体としての１個のミラー３０に代えて、３個のイメージセンサに対向させて上下方向へ３個のミラーを配列して検査領域を分担することもできる。この場合、ミラーは順に制御されることなく、所属の回転角制御信号に応答して所属の駆動部を作動させ、３段のＣＣＤカメラ１０に対して同時に撮像処理させることができる。
【００２３】
図４は別の実施の形態によるスライド駆動装置を示すもので、ミラーの幅を節約するために、前述の支柱３１を支持するミラー支持部５０にラック５１を付設して、ガイドレール５２により搬送路に対して面直方向に対して離接方向にスライド可能にガイドされると共に、ラック５１に歯合するピニオン５３が駆動部５５で回転駆動される。制御手段では、塗面１ａの所定の検査領域の面形状もしくは離間距離のずれに応じて、ミラー３０及びＣＣＤカメラ１０の回転位置の解析と共にミラー３０のスライド位置が解析される。したがって、図５Ａ或は図５Ｂの実線で示すように、塗面１ａの搬送路に正確に平行で、かつ平坦な検査領域に対するミラー３０及びＣＣＤカメラ１０の姿勢に対して、塗面１ａが車両前後方向へ曲面になったり、或は離間距離がずれると、図５Ａ或は図５Ｂの点線で示すように、ミラー３０及びＣＣＤカメラ１０の回転姿勢と共にミラー３０のスライド位置も制御される。
【００２４】
さらに別の実施の形態として、特に塗面１ａの曲面変化が僅かな場合、図１においてミラー３０のみ回転制御してＣＣＤカメラ１０を位置的に固定しておくこともできる。この場合、塗面１ａの僅かな変化により入射光がＣＣＤカメラ１０の中心光軸に対して僅かに斜めに入射しても相応の感度低下を甘受して撮像することができる。また、１個の撮像装置を昇降可能にガイドして車両の搬送速度よりも高速に上下に複数段に撮像走査を行うようにもできる。本発明は、冒頭に説明したように、縞模様を照射する面照射体を備えて、光照射された塗面での正反射光によるイメージセンサの撮像データを画像処理して塗面の平滑度を検査する検査装置等、面照射体と、イメージセンサとを備えて塗面の正反射光を画像処理する種々の方式の検査装置に適用することができる。
【００２５】
【発明の効果】
請求項１の発明によれば、イメージセンサを面発光体に隣合せに配置して塗面の正反射光を光反射体を介して撮像させることにより、イメージセンサの所要の対物距離を確保して、撮像装置を搬送路に接近させることが可能となる。その際、請求項２又は請求項３の発明により、光反射体の回転もしくは離接スライドによる移動により、塗面の距離もしくは特に車両前後方向の曲面状の変化に対しても撮像が可能となる。請求項４又は請求項５の発明によれば上下方向に広い範囲の検査も可能となる。請求項６の発明によれば、イメージセンサが反射光の入射角に応じて面直に入射させるように回転制御されることにより、感度低下が抑制される。
【図面の簡単な説明】
【図１】本発明の実施の形態による車両用塗面検査装置を示す斜視図である。
【図２】同車両用塗面検査装置に付属する回路装置部分の構成を示す図である。
【図３】同車両用塗面検査装置の動作を説明する図である。
【図４】別の実施の形態による車両用塗面検査装置要部を説明する概略平面図である。
【図５】図４による車両用塗面検査装置の動作を説明する図である。
【図６】従来の車両用塗面検査装置の構成を示す正面図である。
【符号の説明】
１ａ車両側面の塗面
１０ＣＣＤカメラ
１５，３４回転駆動部
２０面発光体
３０ミラー
５２ガイドレール[0001]
BACKGROUND OF THE INVENTION
The present invention makes a regular illuminating light incident on a light-illuminated paint surface incident on a surface illuminator that illuminates the paint surface of the vehicle in a plane and a paint surface of the vehicle carried in along the transport path. The present invention relates to a coating surface inspection device for a vehicle, which includes an image sensor to be processed, and inspects a coating surface by processing an image signal of the image sensor.
[0002]
[Prior art]
According to Patent Document 1, as shown in FIG. 6, a surface illuminator 7 that irradiates a surface with parallel light and an image sensor 6 that is disposed laterally with an interval between the surface illuminator are provided, and are regularly reflected. The imaging device 9 that is oriented so that the central optical axes of each other intersect at the front position so that light is incident is attached to the arm tip of the robot 5, and the three-dimensional of the imaging device 9 with respect to the coating surface of the vehicle 1. By scanning the coating surface while controlling the position and orientation, it is detected that the image signal level output from the image sensor 6 decreases from the high signal level corresponding to the normal coating surface, and is applied to the coating surface of the vehicle 1. A vehicular coating surface inspection apparatus that automatically detects a minute defect that has occurred is disclosed.
[0003]
Further, according to Patent Document 2, a surface illuminator that irradiates a surface so as to project a light and dark pattern on a paint surface of a vehicle or the like, and a light reception image of a light and dark pattern obtained by imaging the paint surface are converted into image data. An image sensor oriented so that the center optical axes of each other intersect, extract a boundary area between a bright part and a dark part of a light / dark pattern from image data, and image the light / dark boundary area with a predetermined threshold value A coating film smoothness inspection apparatus that binarizes and determines the smoothness of the coating surface in accordance with the degree of variation in the width of the light / dark boundary region of the binarized image is well known.
[0004]
[Patent Document 1]
JP 2001-133409 A [Patent Document 2]
Japanese Patent Laid-Open No. 9-126744
[Problems to be solved by the invention]
However, an imaging device arranged on both sides of such a surface illuminator and the image sensor is attached to the tip of the robot arm, and in addition to the upper surface of the vehicle to be carried, the side surface is also scanned. Then, not only the structure of the robot itself becomes large, but also it is necessary to prepare these operation spaces in the side region, and there is a problem that the occupied space becomes wide.
[0006]
Therefore, according to Japanese Patent Application No. 2003-131444, the present applicant attaches the surface illuminator and the image sensor to the end portions on both sides of the arm horizontally disposed on the side of the conveyance path, and attaches the arm in the vertical direction. A rotation drive unit that rotates about the horizontal rotation axis of the rotation axis, and a rotation drive unit that rotates the arm in the horizontal plane about the vertical rotation axis at the intermediate position, according to the three-dimensional shape data of a predetermined inspection area, A coating surface inspection device for vehicles was proposed that controls the rotation angle and turning angle of the arm so that specularly reflected light is incident on the image sensor.
[0007]
As a result, the coating surface inspection of the vehicle can be performed without using a structurally large robot and the area occupied by the side of the conveyance path is reduced. This vehicle coating surface inspection device is also disclosed in Patent Document 1 and Patent. As in the apparatus of Document 2, the surface illuminator and the image sensor are arranged apart from each other along the conveyance path, and the respective central optical axes are crossed by the front coating surface, and the coating surface irradiated with light is used. It is assumed that the regular reflected light is incident on the image sensor. Therefore, the separation distance to the coating surface of the image sensor needs to be set corresponding to the shortest objective distance required for image formation.
[0008]
In view of the above, an object of the present invention is to provide a coating surface inspection device for a vehicle that can further save a space necessary for particularly inspecting a coating surface on a vehicle side surface.
[0009]
[Means for Solving the Problems]
In order to achieve this object, the present invention provides, according to claim 1, a surface illuminator that illuminates a painted surface of a vehicle in a plane, and a painted surface of a vehicle that has been carried along a conveyance path. In a vehicular coating surface inspection apparatus, an image sensor for injecting specularly reflected light from a light-irradiated coating surface and processing the image signal of the image sensor to inspect the coating surface. However, it is arranged on the side of the conveyance path so that the painted surface on the side of the vehicle is illuminated horizontally from an oblique direction, and the image sensor is arranged next to the side opposite to the conveyance path of the surface illuminator. On the other hand, a light reflector that causes regular reflection light on the light-irradiated coating surface to enter the image sensor and that is incident on the image sensor is disposed at a position separated along the conveyance path.
[0010]
The regular reflection light on the coating surface irradiated with light from the surface illuminator is reflected by the mirror, prism, etc. on the image sensor placed closer to the original minimum required distance in the direction perpendicular to the transport path. By entering through the body, the required shortest objective distance is substantially ensured.
[0011]
In order to ensure that the reflected light is incident on the image sensor in response to the deviation from the flat reference coating surface at the reference position, the light reflector is supported rotatably around the vertical rotation axis. And a rotation drive unit that controls the rotation position of the light reflector according to the position of the coating surface or the curved surface shape, or according to claim 3, the light reflector is supported rotatably about the vertical rotation axis. The slider is guided by the guide rail so as to be slidable in the contact / separation direction with respect to the conveyance path, and includes a slide drive unit that controls the slide position according to the position of the coating surface or the curved surface shape. In this case, when a plurality of image sensors share the coating surface inspection area, the plurality of image sensors are arranged vertically so as to share the coating surface inspection area. The rotation drive unit sequentially controls the rotational position of one light reflector in accordance with the position of the inspection region or the curved surface shape to be synchronized with the imaging scan for imaging in order of the plurality of image sensors; Alternatively, a plurality of image sensors and a plurality of light reflectors are arranged in the vertical direction so as to share the inspection area of the coating surface according to claim 5, and the position of the inspection area shared by the rotation drive unit or The rotational position of each light reflector is controlled according to the curved surface shape. In order to make the reflected light incident on the image sensor reliably and with high sensitivity corresponding to the deviation from the flat reference coating surface at the reference position, the tip of the image sensor is centered on the vertical rotation axis. A rotation drive unit that is rotatably supported and that controls the rotation position of the image sensor in conjunction with the movement of the light reflector is provided.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
A vehicle coating surface inspection device according to an example of an embodiment of the present invention will be described with reference to FIGS. 1 to 3. An imaging device for a coating surface 1a on the side of a vehicle is attached to a support column 11 with a bracket 21, and a surface emitting body that irradiates a predetermined range with parallel rays using, for example, a straight tube fluorescent lamp as a light source. 20 and a three-stage image sensor in the vertical direction that supports the inspection region and has a tip portion supported by a vertical shaft 17 of a rotary drive unit 15 using a motor supported by a support arm 12 attached to a support column 11. And a single mirror 30 with a rotation drive unit 34 as a light reflector rotatably supported by a pin 33 on a hinge bracket 32 supported by a support column 31 spaced along the conveyance path. It consists of The rotation drive unit 34 uses a motor-driven linear actuator 35 that drives the rod 36 back and forth. A link arm 37 is pivotally attached to the tip of the rod 36 by a pin 37a, and the other end is pivotally attached to the back surface of the mirror 30 by a pin 37b. The mirror 30 is rotationally driven by the advance and retreat of the rod 36.
[0013]
If the shortest objective distance with respect to the coating surface 1a that can form a clear image corresponding to the focal length of the CCD camera 10 is about 1 m at the shortest, the surface light emitter 20 and the CCD camera 10 conventionally have their respective center optical axes. Is 60 to 70 cm away from the coating surface 1a so that they intersect at a predetermined front coating surface 1a at the same inclination angle. The separation distance in the direction is set to, for example, about 35 cm, and the CCD camera 10 is disposed adjacent to the mirror 30 on the side opposite to the conveyance path side of the surface light emitter 20, and passes through the mirror 30 from the coating surface 1 a. The incident path reaching 10 is set so that at least about 1 m can be secured.
[0014]
A three-dimensional shape measuring instrument 40 that measures the three-dimensional shape of the coating surface 1a on the side surface of the vehicle in a non-contact manner on the upstream side of the conveyance path with respect to the imaging device measures each of the sharing ranges of the three-stage imaging devices. As shown in the figure, it is attached to the support column 41 at intervals in three steps in the vertical direction. This three-dimensional shape measuring instrument has a separation distance of about 35 cm with respect to the conveying path, emits a laser beam, scans the surface of the coating surface 1a, and the incident position of reflected laser light on the coating surface based on the principle of triangulation The three-dimensional shape is measured by analyzing the three-dimensional position based on the scanning angle. In addition, various types of apparatuses are widely used as apparatuses for measuring a three-dimensional shape based on three-dimensional position data in an optical non-contact state.
[0015]
Such a coated surface inspection device for a side surface is also disposed in a side surface region on the opposite side of the conveyance path, and scans the coated surface by attaching an imaging device to the tip of the arm so as to inspect the coated surface on the upper surface. A robot is also installed.
[0016]
As shown in FIG. 2, both rotation drive units 15 and 34 control the mirror 30 and the rotation angle of the CCD camera 10 so that the specularly reflected light in a predetermined inspection area of the coating surface 1 a is transmitted to the CCD camera 10. Control means 44, 44a, and 44b for the upper, middle, and lower stages that sequentially output the mirror and CCD camera rotation angle control signals in synchronization with the vehicle transport so as to be incident parallel to the central optical axis are attached. . The three three-dimensional shape measuring devices 40 sequentially measure the surface shape of a predetermined inspection region of the coating surface 1a in synchronization with the vehicle transport, and are normal to the three-dimensional position of the central portion. And normal analysis means 43, 43a, and 43b for the upper, middle, and lower stages are output.
[0017]
That is, this normal analysis means is synchronized with the carry-in position of the vehicle so that surface measurement is performed for each inspection area of about 20 square cm, for example, and one mirror 30 is controlled in three stages. In response to the measurement command signal supplied from the sequential control panel with a slight delay, the sequential analysis results are output. The control means 44, 44 a, 44 b analyze the reflection direction of the specularly reflected light with respect to the normal data at the three-dimensional position of the input belonging central part, and convert the specularly reflected light at the central part of each inspection region to the CCD camera 10. The rotation angle of the CCD camera 10 and the mirror 30 incident in parallel to the central optical axis of the navel is analyzed, and an imaging command signal delayed from a measurement command signal belonging to a predetermined time corresponding to the transport speed is sequentially supplied from the control panel. In response to this, the analyzed rotation angle control signal is output, and immediately after that, imaging is performed at a timing at which the imaging region matches the measurement region to which it belongs.
[0018]
As described in Patent Document 1, the image processing device 45 determines whether or not the image signal level captured by the CCD camera 10 is reduced by a predetermined amount from the high signal level corresponding to the normal coating surface. Is detected. The display data creation means 46 creates graphic data for the vehicle 1 and performs graphic processing on the supplied image processing data on both sides and the upper surface, thereby superimposing the graphic on the vehicle image to indicate the position of the minute defect. Data is created and displayed on an image display device or printed out by a printer.
[0019]
The operation of the coating surface inspection apparatus for a vehicle configured as described above will be described with reference to FIG. When the vehicle 1 is brought into the facing position of the three-dimensional shape measuring instrument 40, the predetermined inspection area of the coating surface 1a of about 20 square cm is successively 20 cm in the conveyance direction with a slight delay time in three stages. It is measured every time the shift is performed, and the normal line at the center of the inspection area measured each time is analyzed based on the surface shape of the three-dimensional position. The mirror 30 and the upper CCD camera 10 are analyzed so that the reflected light of the mirror 30 is incident on the CCD camera 10 in a plane corresponding to the normal data of a predetermined inspection region of the upper three-dimensional shape measuring instrument 40. By controlling the rotation position according to the rotation angle, the reflected light of the regular reflection light with respect to the irradiation light with a constant irradiation angle is shallower than the irradiation angle of the surface light emitter 20 as indicated by the solid line. It enters the CCD camera 10 at an incident angle.
[0020]
Next, the mirror 30 and the rotational positions of the middle and lower CCD cameras 10 are sequentially controlled at a sufficiently higher speed than the conveyance speed in accordance with the measurement results of the middle and lower three-dimensional shape measuring instruments 40, and imaging is performed. Such vertical imaging scanning is repeated in the transport direction, the image signal of each inspection area is processed, and the inspection result of the vehicle 1 is graphically displayed together with the image processing data of the opposite side surface and upper surface. It is displayed and can be output to a monitor or printer.
[0021]
If the coating surface 1a becomes a curved surface in the longitudinal direction of the vehicle as shown by the dotted line in FIG. A, or if it is away from a predetermined separation distance as shown by the dotted line in FIG. Correspondingly, the rotational positions of the mirror 30 and the CCD camera 10 are controlled accordingly. Even if the surface shape slightly changes around the three-dimensional position of the central portion serving as a reference for the normal line, the inspection can be performed by slight diffusion of parallel rays emitted from the surface light emitter 20. The rotation control is performed on a horizontal plane, but the inspection can be performed in the same manner even when slightly bent in the vertical direction.
[0022]
The rotational positions of the mirror 30 and the CCD camera 10 can be controlled in accordance with the shape of the vehicle. However, as described above, the three-dimensional shape measuring instrument 40 is prepared and measured. By controlling the rotation position with the data, it is possible to avoid the occurrence of an error in the inspection result due to the mounting position of the vehicle on the conveyance path deviating from the normal position. Furthermore, instead of the single mirror 30 as the light reflector, the inspection region can be shared by arranging three mirrors in the vertical direction so as to face the three image sensors. In this case, the mirrors are not controlled in sequence, and the associated drive unit is operated in response to the associated rotation angle control signal, so that the three-stage CCD camera 10 can simultaneously perform imaging processing.
[0023]
FIG. 4 shows a slide drive device according to another embodiment. In order to save the width of the mirror, a rack 51 is attached to the mirror support portion 50 that supports the support column 31 and is conveyed by the guide rail 52. A pinion 53 that is slidably guided in a direction away from the surface perpendicular to the road and that meshes with the rack 51 is rotationally driven by the drive unit 55. In the control means, the slide position of the mirror 30 is analyzed together with the analysis of the rotational positions of the mirror 30 and the CCD camera 10 in accordance with the deviation of the surface shape or the separation distance of the predetermined inspection area of the coating surface 1a. Therefore, as shown by the solid line in FIG. 5A or 5B, the coating surface 1a is a vehicle with respect to the attitude of the mirror 30 and the CCD camera 10 with respect to the flat inspection region that is exactly parallel to the conveyance path of the coating surface 1a. When a curved surface is formed in the front-rear direction or the separation distance is deviated, the slide position of the mirror 30 is controlled together with the rotation posture of the mirror 30 and the CCD camera 10 as shown by the dotted lines in FIG. 5A or 5B.
[0024]
As still another embodiment, particularly when the curved surface of the coating surface 1a is slight, only the mirror 30 in FIG. 1 can be rotationally controlled to fix the CCD camera 10 in position. In this case, even if the incident light is incident slightly obliquely with respect to the central optical axis of the CCD camera 10 due to a slight change in the coating surface 1a, it is possible to take an image with a corresponding decrease in sensitivity. It is also possible to guide one imaging device so that it can be moved up and down, and to perform imaging scanning in a plurality of stages up and down at a speed higher than the conveyance speed of the vehicle. As described above, the present invention includes a surface illuminator that irradiates a striped pattern, and performs image processing on imaging data of an image sensor by specular reflection light on a light-irradiated paint surface, thereby smoothing the paint surface. The present invention can be applied to various types of inspection apparatuses that include a surface illuminator and an image sensor, such as an inspection apparatus that inspects the image of the specular reflection light on the coating surface.
[0025]
【The invention's effect】
According to the first aspect of the present invention, a required objective distance of the image sensor is ensured by arranging the image sensor next to the surface light emitter and imaging the specularly reflected light of the coating surface through the light reflector. Thus, it is possible to bring the imaging device closer to the conveyance path. In this case, according to the invention of claim 2 or claim 3, it is possible to take an image even with respect to the distance of the coating surface or a change in the curved surface shape in the longitudinal direction of the vehicle by the rotation of the light reflector or the movement by the contact slide. . According to the invention of claim 4 or claim 5, inspection in a wide range in the vertical direction is also possible. According to the sixth aspect of the invention, the image sensor is controlled to rotate so that it is incident on the surface in accordance with the incident angle of the reflected light, thereby suppressing a decrease in sensitivity.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a coating surface inspection apparatus for a vehicle according to an embodiment of the present invention.
FIG. 2 is a diagram showing a configuration of a circuit device portion attached to the coating surface inspection apparatus for a vehicle.
FIG. 3 is a diagram for explaining the operation of the vehicular coating surface inspection apparatus.
FIG. 4 is a schematic plan view for explaining a main part of a coating surface inspection apparatus for a vehicle according to another embodiment.
FIG. 5 is a diagram for explaining the operation of the coating surface inspection apparatus for a vehicle according to FIG. 4;
FIG. 6 is a front view showing a configuration of a conventional vehicular coating surface inspection apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1a Coated surface 10 of vehicle side CCD camera 15, 34 Rotation drive part 20 Surface light emitter 30 Mirror 52 Guide rail

Claims

A surface illuminator that illuminates a painted surface of a vehicle in a planar shape, and an image sensor that causes regular reflected light on the coated surface irradiated with light to be incident on the painted surface of the vehicle carried along the conveyance path; In the vehicle paint surface inspection device that has been adapted to inspect the paint surface by processing the image signal of this image sensor,
The surface illuminator is disposed on the side of the conveyance path so as to irradiate the coating surface on the side surface of the vehicle horizontally and obliquely, and the image sensor is disposed adjacent to the side opposite to the conveyance path of the surface illuminator. ,
A light reflector that causes regular reflection light on the coating surface irradiated with light to enter the image sensor and to make the reflected light incident on the image sensor is disposed at a position separated from the image sensor along the conveyance path. A paint surface inspection apparatus for vehicles characterized by the above.

The light reflector is supported rotatably about a vertical rotation axis, and includes a rotation drive unit that controls the rotation position of the light reflector according to the position of the coating surface or the curved surface shape. The coating surface inspection apparatus for vehicles of Claim 1.

A slider that supports the light reflector so as to be rotatable about a vertical rotation axis is guided by a guide rail so as to be slidable in a direction away from the conveyance path, and is also slid according to the position of the coating surface or the curved surface shape. The vehicular coating surface inspection apparatus according to claim 2, further comprising a slide drive unit that controls the vehicle.

A plurality of image sensors are arranged in the vertical direction so as to share the inspection area of the coating surface, and the rotation drive unit is synchronized with and shares the imaging scan for imaging in order of the plurality of image sensors. 3. The coating surface inspection apparatus for a vehicle according to claim 2, wherein the rotation position of one light reflector is sequentially controlled in accordance with the position of the inspection area or the curved surface shape.

A plurality of image sensors and a plurality of light reflectors are arranged in the vertical direction so as to share the inspection area of the coating surface, and the rotation driving unit is responsive to the position or curved surface shape of the inspection area to be shared. The vehicle coating surface inspection device according to claim 2, wherein the rotational position of each light reflector is controlled.

The front end of the image sensor is supported rotatably about a vertical rotation axis, and further includes a rotation drive unit that controls the rotation position of the image sensor in conjunction with the movement of the light reflector. The coating surface inspection apparatus for vehicles according to any one of claims 2 to 5.