JPH0989524A - Method and device for detecting center position of welding groove or bead - Google Patents
Method and device for detecting center position of welding groove or beadInfo
- Publication number
- JPH0989524A JPH0989524A JP24896995A JP24896995A JPH0989524A JP H0989524 A JPH0989524 A JP H0989524A JP 24896995 A JP24896995 A JP 24896995A JP 24896995 A JP24896995 A JP 24896995A JP H0989524 A JPH0989524 A JP H0989524A
- Authority
- JP
- Japan
- Prior art keywords
- bead
- center
- groove
- cross
- edge
- 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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Links
Landscapes
- Length Measuring Devices By Optical Means (AREA)
Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、溶接開先やビード
を含む測定対象物の断面形状を検出し、該検出された断
面形状から、開先肩部の中心としての開先中心や、ビー
ドエッジの中心としてのビード中心を認識するための溶
接開先・ビードの中心位置検出方法及び装置に係り、特
に、ＵＯ鋼管等の自動倣い溶接や自動倣い探傷に用いる
のに好適な、２次元画像の処理を必要とすることなく、
１次元の断面形状から、溶接肩部やビードエッジを正確
に検出することが可能な、溶接開先・ビードの中心位置
検出方法及び装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects the cross-sectional shape of a measuring object including a weld groove and a bead, and based on the detected cross-sectional shape, the groove center as the center of the groove shoulder and the bead edge. The present invention relates to a welding groove / bead center position detecting method and apparatus for recognizing a bead center as a center of a bead, and particularly, a two-dimensional image suitable for use in automatic profile welding and automatic profile flaw detection of UO steel pipes and the like. Without the need for processing
The present invention relates to a welding groove / bead center position detecting method and device capable of accurately detecting a welding shoulder portion or a bead edge from a one-dimensional cross-sectional shape.
【０００２】[0002]
【従来の技術】従来、開先中心やビード中心の検出に
は、２次元画像の認識によるパターンマッチング方法
や、１次元の断面形状を１階又は２階差分する方法が行
われている。前者の方法としては、三菱重工技報Ｖｏ
ｌ．３１Ｎｏ．３（１９９４）２１７頁に示される方法
が知られており、又、後者の方法としては、特開昭６０
−３０５７８に示される方法が知られている。2. Description of the Related Art Conventionally, in order to detect a groove center or a bead center, a pattern matching method by recognizing a two-dimensional image or a method of differentiating a one-dimensional sectional shape by the first or second floor is performed. As the former method, Mitsubishi Heavy Industries Technical Report Vo
l. 31 No. 3 (1994) page 217, and the latter method is disclosed in JP-A-60
The method shown in -30578 is known.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、２次元
画像の認識によるパターンマッチング方法では、２次元
の広い部分の情報を比べるため、大局的な判断を行える
反面、２次元平面分の演算が必要になるため、演算を行
う計算機に高速・高価なものを必要とし、特に高速動作
を要求される探傷工程への応用には、難しいものがあっ
た。又、２次元画像を必要とするので、画像の取得自体
にも、高速・高価な機器を必要とするという問題点を有
していた。However, in the pattern matching method based on the recognition of a two-dimensional image, since information on a wide two-dimensional portion is compared, it is possible to make a global judgment, but an operation for a two-dimensional plane is required. Therefore, it is necessary to use a high-speed and expensive computer for calculation, and it is difficult to apply it especially to the flaw detection process that requires high-speed operation. In addition, since a two-dimensional image is required, there is a problem that a high-speed and expensive device is required for acquiring the image itself.
【０００４】一方、断面形状を１階差分する方法では、
画像データ自身は１次元であるため、２次元画像の認識
によるパターンマッチング方法に比べて、処理は速くな
るが、一般に、差分値が一定値を連続して、ある区間越
えたときをもって開先肩部又はビードエッジとする判定
を行っており、この方法では、画像全体又は部分の傾斜
を開先肩部又はビードエッジと誤認識する場合が多いと
いう問題点を有していた。On the other hand, in the method of subtracting the cross-sectional shape by the first floor,
Since the image data itself is one-dimensional, the processing is faster than the pattern matching method by recognizing a two-dimensional image, but in general, when the difference value continuously exceeds a certain value and exceeds a certain interval, The determination is made as a part or a bead edge, and this method has a problem that the inclination of the entire image or a part is often mistakenly recognized as a groove shoulder or a bead edge.
【０００５】即ち、図１に示す１階差分法では、鋼管断
面の外面形状１０の微小突起１２による１階差分値ｇ1
の増加、及び、開先以外の管表面での１階差分値ｇ1 の
増加が大きく、仮付溶接ビード部１４のビードエッジ１
６の１階差分値よりはるかに大きくなっており、ビード
エッジ１６の検出が、微小突起１２及び管面の曲率の影
響で難しくなっていることが分かる。That is, in the first-order difference method shown in FIG. 1, the first-order difference value g 1 due to the small protrusions 12 of the outer surface shape 10 of the steel pipe cross section is used.
And the first-order difference value g 1 on the pipe surface other than the groove are large, and the bead edge 1 of the tack weld bead portion 14 is large.
It is much larger than the first-order difference value of 6, and it can be seen that the detection of the bead edge 16 is difficult due to the influence of the curvature of the minute projections 12 and the tube surface.
【０００６】この１階差分法における、傾斜部を開先肩
部又はビードエッジと誤認識する欠点を避けるため、画
像を２階差分し、２階差分値が一定値を、ある区間連続
して越えた点をもって、開先肩部又はビードエッジとす
る方法も知られている（特開昭６０−３０５７８参
照）。In order to avoid the disadvantage of erroneously recognizing the inclined portion as a groove shoulder or a bead edge in the first-order difference method, the image is subjected to a second-order difference and the second-order difference value exceeds a certain value continuously for a certain section. There is also known a method of forming a grooved shoulder portion or a bead edge with respect to the above (see JP-A-60-30578).
【０００７】この２階差分法によれば、傾斜を誤認識す
る恐れは少なくなるものの、差分値が同じ、即ち局所的
な傾斜が似ている小突起と、開先肩部又はビードエッジ
を区別することは難しく、小突起が多いデータでは誤認
識を多く生ずるという問題点を有していた。According to the second-order difference method, although there is less risk of erroneously recognizing the inclination, small projections having the same difference value, that is, similar local inclinations are distinguished from the groove shoulder or the bead edge. However, there is a problem in that data with many small protrusions often causes erroneous recognition.
【０００８】即ち、この２階差分法によれば、図２に示
す如く、管面曲率の影響による２階差分値ｇ2 の増加は
小さくなるものの、微小突起１２による２階差分値ｇ2
の増加が大きく、ビードエッジ１６の２階差分値に近く
なっており、これもビードエッジ１６の確実な判断を難
しくしている。Namely, according to the second-order difference method, as shown in FIG. 2, although the increase in the second-order difference g 2 due to the influence of the tube surface curvature becomes smaller, the second-order difference g 2 by microprotrusions 12
Of the bead edge 16 is close to the second-order difference value of the bead edge 16, which also makes it difficult to reliably determine the bead edge 16.
【０００９】なお、前記１階差分値ｇ1 及び２階差分値
ｇ2 は、次式で計算している。The first-order difference value g 1 and the second-order difference value g 2 are calculated by the following equations.
【００１０】 ｇ1 （ｉ）＝Ｐ（ｉ）−Ｐ（ｉ−Ｎg ） …（１） ｇ2 （ｉ）＝Ｐ（ｉ＋Ｎg ）＋Ｐ（ｉ−Ｎg ） …（２） ｇ1 （ｉ）：点ｉでの１階差分値 ｇ2 （ｉ）：点ｉでの２階差分値 Ｐ（ｉ）：断面形状曲線（各点ｉでのドットの集合で表
現） Ｎg ：差分区間の長さ（ドット数）G 1 (i) = P (i) −P (i−N g ) ... (1) g 2 (i) = P (i + N g ) + P (i−N g ) ... (2) g 1 ( i): First-order difference value at point i g 2 (i): Second-order difference value at point i P (i): Cross-sectional shape curve (expressed as a set of dots at each point i) N g : Difference section Length (number of dots)
【００１１】上記１階差分法及び２階差分法の問題点
は、差分法特有の、極く狭い部分間の局所的演算で、開
先肩部又はビードエッジを決定するという問題点を反映
したものと考えられる。The above-mentioned problems of the first-order difference method and the second-order difference method reflect the problem of determining the groove shoulder or the bead edge by the local calculation between the extremely narrow parts, which is peculiar to the difference method. it is conceivable that.
【００１２】又差分法の変形として、特開平４−１１５
１０４には、撮像器が捉らえた画像に対して、画面上端
あるいは下端から断面形状を示す図形までの距離を画面
左端から右端にわたって計算し、この距離の変化分が
＋、０あるいは−かをチェックし、＋から−へ、又は−
から＋へと変化した変曲点の位置を検出して、該変曲点
を境とした距離の変化分の＋、−勾配の組合せにより、
予め設定されているパターンのどれに属するかというパ
ターン分類を実施して、分類されたパターンに対して開
先のエッジ位置を算出する方法が記載されている。しか
しながら、この方法においても、十分に高精度な検出を
行うことはできなかった。As a modification of the difference method, Japanese Patent Laid-Open No. 4-115.
In 104, the distance from the top or bottom of the screen to the figure showing the cross-sectional shape is calculated from the left end to the right end of the screen for the image captured by the image pickup device, and whether the change in the distance is +, 0, or-is displayed. Check and go from + to-or-
The position of the inflection point that has changed from + to + is detected, and by the combination of the + and-gradients of the change in distance with the inflection point as the boundary,
There is described a method of performing pattern classification as to which of preset patterns belongs and calculating an edge position of the groove for the classified pattern. However, even with this method, it was not possible to perform detection with sufficiently high accuracy.
【００１３】本発明は、前記従来の問題点を解消するべ
くなされたもので、比較的安価・低速の画像取得装置及
び演算装置を用い、差分法の局所的演算による問題点を
改良した大局的演算により、誤認識が少なく、且つ高速
で開先肩部やビードエッジを検出することを目的とす
る。The present invention has been made in order to solve the above-mentioned conventional problems, and is a global view in which the problems due to the local calculation of the difference method are improved by using a relatively inexpensive and low-speed image acquisition device and a calculation device. The purpose is to detect the shoulder portion of the groove and the bead edge at a high speed with less misrecognition by calculation.
【００１４】[0014]
【課題を解決するための手段】本発明は、溶接開先やビ
ードを含む測定対象物の断面形状を検出し、該検出され
た断面形状から、開先肩部の中心としての開先中心や、
ビードエッジの中心としてのビード中心を認識するため
の溶接開先・ビードの中心位置検出方法において、前記
断面形状に沿って、直線又はＮ次多項式曲線を逐次当て
嵌めていき、両者のずれが大きくなった時に、開先肩部
又はビードエッジと判定することようにして、前記目的
を達成したものである。The present invention detects the cross-sectional shape of an object to be measured including a weld groove and a bead, and based on the detected cross-sectional shape, a groove center as the center of a groove shoulder and ,
In the welding groove / bead center position detecting method for recognizing the bead center as the center of the bead edge, a straight line or an Nth degree polynomial curve is successively fitted along the cross-sectional shape, and the deviation between the two becomes large. The above object is achieved by determining that the groove is a shoulder or a bead edge.
【００１５】又、溶接開先・ビードの中心位置検出装置
を、溶接開先やビードを含む測定対象物の断面形状を検
出する手段と、検出された断面形状に沿って、直線又は
Ｎ次多項式曲線を、両者のずれが最小となるよう逐次当
て嵌めていく手段と、当て嵌められた直線又はＮ次多項
式曲線と断面形状とのずれを計算する手段と、該ずれが
所定値以上となった時に、開先肩部又はビードエッジと
判定する手段と、該判定結果に基づいて、開先肩部の中
心としての開先中心又はビードエッジの中心としてのビ
ード中心を認識する手段とを用いて構成することによ
り、同じく前記目的を達成したものである。Further, a welding groove / bead center position detecting device is provided with means for detecting the sectional shape of the measuring object including the welding groove and the bead, and a straight line or an Nth degree polynomial along the detected sectional shape. A means for successively fitting the curves so that the deviation between them is minimized, a means for calculating the deviation between the fitted straight line or the Nth degree polynomial curve and the cross-sectional shape, and the deviation is a predetermined value or more. Sometimes, it is configured by using means for determining the groove shoulder or bead edge, and means for recognizing the groove center as the center of the groove shoulder or the bead center as the center of the bead edge based on the determination result. As a result, the above-mentioned object is also achieved.
【００１６】以下、本発明の作用を説明する。The operation of the present invention will be described below.
【００１７】図３（ａ）に示す如く、レーザスリット光
等により得られた開先又はビードの断面形状の離散的な
点を２次元直交座標上で表現した曲線をＰ（ｉ）とす
る。ここで、変数ｉは何個目の点であるかを示す。Ｐ
（ｉ）は、断面形状の離散的な点のｉ番目のｙ座標を表
わすことになる。As shown in FIG. 3A, a curve that represents discrete points of the groove or bead cross-sectional shape obtained by laser slit light or the like on two-dimensional orthogonal coordinates is P (i). Here, the variable i indicates the number of the point. P
(I) represents the i-th y coordinate of the discrete points of the cross-sectional shape.
【００１８】ここで、最も簡単な場合として、Ｎ＝１、
即ち、ある長さの直線を断面形状Ｐ（ｉ）に、端から順
に当て嵌めていく例を説明する。この直線上の離散的な
点は、次式で表わされる。Here, in the simplest case, N = 1,
That is, an example will be described in which a straight line having a certain length is fitted to the cross-sectional shape P (i) in order from the end. The discrete points on this straight line are expressed by the following equation.
【００１９】 ｙi （ｊ）＝ａｉ・ｊ＋ｂi …（３）Y i (j) = ai · j + b i (3)
【００２０】ｊは、ｉ−Ｎｂ＋１からｉまで動かす。即
ち、（３）式の直線はＮｂ個の点を含んでおり、且つ、
一方から端（右端）がｉ番目となることを示している。
ここで、ａi 、ｂi を、例えば次式に示す２乗残差Ｒ
(2) を最小にするように選ぶ。J moves from i-Nb + 1 to i. That is, the straight line of the equation (3) includes Nb points, and
It shows that the edge (right edge) from one side is the i-th.
Here, a i and b i are represented by, for example, the square residual R
Choose to minimize (2) .
【００２１】 [0021]
【００２２】これは最小２乗法と知られている方法であ
り、これにより、直線は断面形状曲線によく当て嵌まる
ようになることが知られている。This is a method known as the least squares method, and it is known that the straight line fits well to the cross-sectional shape curve.
【００２３】この操作を各ｉについて行い、それによっ
て決定されたａi 、ｂi を使って残差を計算する。この
残差をＲim(2) とする。このＲim(2) を、ｉを横軸とし
てグラフとすると、図３（ｂ）に示す如く、管面部のよ
うな平坦な部分では当て嵌めの程度がよいので残差Ｒim
(2) は小さいが、開先肩分やビードエッジ等の平坦でな
い部分にくると、当て嵌めがうまくいかなくなり、残差
Ｒim(2) は急速に大きくなる。従って、この残差Ｒim
(2) がある値以上に大きくなる点を捜せば、そこが開先
肩部又はビードエッジと判定できることになる。This operation is performed for each i, and the residuals are calculated using the a i and b i thus determined. Let this residual be Rim (2) . When this Rim (2) is plotted in the graph with i as the horizontal axis, as shown in FIG. 3 (b), the degree of fitting is good in a flat portion such as the tube surface portion, so the residual error Rim (2)
Although (2) is small, when it comes to an uneven portion such as a groove shoulder or a bead edge, fitting becomes unsuccessful, and the residual Rim (2) rapidly increases. Therefore, this residual Rim
(2) If you look for a point that becomes larger than a certain value, it can be determined as a groove shoulder or bead edge.
【００２４】上記の説明では、Ｎ＝１の直線を当て嵌め
ていく場合であったが、Ｎ＝２の放物線、Ｎ＝３以上の
多項式曲線でも、同様に当て嵌めを行うことが可能であ
る。In the above description, the case of fitting a straight line of N = 1 was used, but it is also possible to fit a parabola of N = 2 and a polynomial curve of N = 3 or more. .
【００２５】又、残差も、上記の２乗残差Ｒim(2) では
なく、次式に示すような絶対値残差Ｒi （∞）を用いて
もよい。As the residual, the absolute value residual R i (∞) as shown in the following equation may be used instead of the square residual Rim (2) .
【００２６】 [0026]
【００２７】本発明によれば、まず直線又はＮ次多項式
曲線の当て嵌めを行うため、例えば傾斜した断面形状曲
線でも、それに応じて傾斜した当て嵌めが行われ、傾斜
による残差の増加が全くない。従って、１階差分法の問
題点である、傾斜面による誤認識は完全に防止できる。
又、Ｎ次の字数を適当に選べば、断面形状の曲がりにも
適切な嵌め合いが行えるため、不要な曲がりの影響も除
去できる。更に、特殊な断面形状に対しても、それに見
合った特殊な曲線を使用することもできる。又、残差
は、当て嵌め曲線の区間全体にわたる量であるため、開
先肩部やビードエッジに傾斜がよく似た微小突起による
残差の影響は小さく、目的である区間Ｎｂ程度以上にわ
たる大きな開先肩部やビードエッジでは、残差が急速に
大きくなるようになり、２階差分法の欠点も除ける。According to the present invention, since a straight line or a polynomial curve of degree N is first fitted, for example, even in the case of a slanted sectional shape curve, slanted fitting is performed accordingly, and the residual error due to the slant is increased at all. Absent. Therefore, erroneous recognition due to the inclined surface, which is a problem of the first-order difference method, can be completely prevented.
Further, if the number of Nth-order characters is properly selected, fitting can be appropriately performed even in the bending of the cross-sectional shape, so that the influence of unnecessary bending can be eliminated. Further, for a special cross-sectional shape, it is possible to use a special curve corresponding to it. Further, since the residual error is the amount over the entire section of the fitting curve, the effect of the residual error due to the minute projections having a similar inclination to the groove shoulder portion or the bead edge is small, and the large opening over the target section Nb or more. At the front shoulder and the bead edge, the residual error rapidly increases, and the disadvantage of the second difference method can be eliminated.
【００２８】[0028]
【発明の実施の形態】以下図面を参照して、本発明の実
施形態を詳細に説明する。BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.
【００２９】本実施形態は、本発明を、溶接トーチを開
先中心に倣わせるように働く自動倣い溶接装置に適用し
たもので、図４に示す如く、測定（溶接）対象である、
開先部分３１を有する鋼管３０に、測定用のレーザスリ
ット光３４を照射するための光源（図示省略）、及び、
鋼管３０表面におけるレーザスリット光の反射位置を検
出するための電荷結合素子３６が内蔵された光学部３２
と、前記電荷結合素子３６の出力から、断面形状を示す
画像を取得する画像取得装置３８と、該画像取得装置３
８の出力を処理して、本発明により開先肩部又はビード
エッジを検出する開先肩部・ビードエッジ検出装置４０
と、該開先肩部・ビードエッジ検出装置４０から出力さ
れる開先中心・ビード中心信号とトーチ中心信号の差を
計算する減算器４２と、該減算器４２出力のビード〜ト
ーチ中心間偏差信号に応じて、前記光学部３２と同じ架
台４４に固定されている溶接トーチ４６の位置を制御す
るためのトーチ駆動用アクチュエータ４８と、を備えて
いる。The present embodiment is an application of the present invention to an automatic profile welding apparatus that works so as to follow a welding torch along the groove center, and is a measurement (welding) target as shown in FIG.
A light source (not shown) for irradiating the steel pipe 30 having the groove portion 31 with the laser slit light 34 for measurement, and
An optical unit 32 having a built-in charge-coupled device 36 for detecting the reflection position of the laser slit light on the surface of the steel pipe 30.
An image acquisition device 38 that acquires an image showing a cross-sectional shape from the output of the charge-coupled device 36, and the image acquisition device 3
A groove shoulder / bead edge detector 40 for processing the output of FIG. 8 and detecting a groove shoulder or bead edge according to the present invention.
And a subtractor 42 for calculating the difference between the groove center / bead center signal and the torch center signal output from the groove shoulder / bead edge detection device 40, and a bead-torch center deviation signal output from the subtractor 42. Accordingly, a torch drive actuator 48 for controlling the position of the welding torch 46 fixed to the same pedestal 44 as the optical unit 32 is provided.
【００３０】前記開先肩部・ビードエッジ検出装置４０
は、図５に詳細に示す如く、前記画像取得装置３８で検
出された断面形状に沿って、直線を、両者のずれが最小
となるよう逐次当て嵌めていく直線当て嵌め回路５０
と、該直線当て嵌め回路５０によって当て嵌められた直
線と断面形状とのずれを示す２乗残差Ｒim(2) を計算す
る２乗残差計算回路５２と、該２乗残差計算回路５２で
計算された２乗残差Ｒim (2) が所定値以上となったとき
に、開先肩部又はビードエッジと判定する開先肩部・ビ
ードエッジ判定回路５４と、該開先肩部・ビードエッジ
判定回路５４における判定結果に基づいて、開先肩部の
中心としての開先中心又はビードエッジの中心としての
ビード中心を認識して、開先中心・ビード中心信号を出
力する開先中心・ビード中心認識回路５６とを含んで構
成されている。The groove shoulder / bead edge detecting device 40
Is detected by the image acquisition device 38, as shown in detail in FIG.
A straight line along the drawn cross-sectional shape, with the minimum deviation between the two
Straight line fitting circuit 50 that sequentially fits so that
And the straight line fitted by the straight line fitting circuit 50.
Squared residual Rim indicating the deviation between the line and the cross-sectional shape(2)Calculate
The square residual calculation circuit 52 and the square residual calculation circuit 52
Calculated squared residual Rim (2)When is greater than or equal to the specified value
The beveled edge or beveled edge.
The edge determination circuit 54 and the shoulder / bead edge of the groove
Based on the determination result of the determination circuit 54,
As groove center as center or as bead edge center
Recognizes the center of the bead and outputs a groove center / bead center signal
It includes a groove center / bead center recognition circuit 56 that applies force.
Has been established.
【００３１】なお、前記実施形態においては、本発明
が、自動習い溶接装置に適用されていたが、本発明の適
用対象はこれに限定されず、例えばビード探傷用のセン
サーをビード中心に倣わせるように働く自動倣い探傷装
置にも同様に適用できることは明らかである。In the above embodiment, the present invention is applied to the automatic learning welding apparatus, but the application target of the present invention is not limited to this. For example, a bead flaw detection sensor is made to follow the bead center. It is obvious that the same can be applied to an automatic copying flaw detector that works likewise.
【００３２】[0032]
【実施例】仮付溶接後の鋼管の右エッジを検出するた
め、本発明による方法を適用した例を図６に示す。この
図６は、図１に示した１階差分法及び図２に示した２階
差分法と同一部分に、本発明を適用したものである。本
発明によれば、管曲率の影響による２乗残差Ｒim(2) の
増加が小さい上、微小突起部１２の影響による残差増加
も小さく、ビードエッジ１６と微小突起１２での残差の
比は、図２に示した２階差分法におけるビードエッジ１
６の２階差分値と微小突起１２の２階差分値の比と同等
又は、これより大きくなっており、ビードエッジ１６の
確実な判断が容易にできる。EXAMPLE FIG. 6 shows an example in which the method according to the present invention is applied to detect the right edge of a steel pipe after tack welding. In FIG. 6, the present invention is applied to the same parts as the first-order difference method shown in FIG. 1 and the second-order difference method shown in FIG. According to the present invention, the increase of the square residual Rim (2) due to the influence of the tube curvature is small, and the increase of the residual due to the influence of the minute protrusions 12 is small, and the ratio of the residual difference between the bead edge 16 and the minute protrusions 12 is small. Is the bead edge 1 in the second-order difference method shown in FIG.
The ratio of the second-order difference value of 6 and the second-order difference value of the minute protrusions 12 is equal to or larger than this ratio, and the reliable determination of the bead edge 16 can be easily performed.
【００３３】なお、実用的には、検出される部分は必ず
しも完全なビードエッジ１６でなくともよく、若干ビー
ド内側でもよい。これは、最終目的が、ビード中心又は
開先中心を求めるものであることによるが、このような
場合には、そのビードと微小突起１２の残差の比は非常
に大きくなり、ビードエッジ１６の検出は、極めて容易
且つ確実なものとなる。In practice, the portion to be detected need not be the complete bead edge 16, but may be slightly inside the bead. This is because the final purpose is to obtain the center of the bead or the groove, but in such a case, the ratio of the residual difference between the bead and the minute protrusion 12 becomes very large, and the bead edge 16 is detected. Is extremely easy and reliable.
【００３４】なお、この実施例では、仮付溶接後の鋼管
のビードエッジの検出例を示したが、仮付溶接前の鋼管
の開先肩部検出や、本溶接後のビードエッジ検出にも、
同様に本発明が適用できることは明らかである。In this embodiment, an example of detecting the bead edge of the steel pipe after tack welding is shown, but it is also possible to detect the bevel edge of the steel pipe before tack welding and to detect the bead edge after main welding.
It will be clear that the invention is likewise applicable.
【００３５】[0035]
【発明の効果】以上説明したとおり、本発明によれば、
平面画像認識装置によるパターンマッチング方法等のよ
うに、高速且つ高価な装置を用いることなく、対象区間
からの情報による大局的な判断で、開先肩部又はビード
エッジを正確に検出することが可能となる。As described above, according to the present invention,
Without using a high-speed and expensive device such as a pattern matching method using a plane image recognition device, it is possible to accurately detect the groove shoulder or the bead edge by the global judgment based on the information from the target section. Become.
【図１】従来の１階差分法によるビードエッジ検出例を
示す線図FIG. 1 is a diagram showing an example of bead edge detection by a conventional first-order difference method.
【図２】同じく２階差分法によるビードエッジ検出例を
示す線図FIG. 2 is a diagram showing an example of bead edge detection by the second-order difference method.
【図３】本発明による検出原理を示す線図FIG. 3 is a diagram showing a detection principle according to the present invention.
【図４】自動倣い溶接装置に適用された本発明の実施形
態の構成を示すブロック線図FIG. 4 is a block diagram showing a configuration of an embodiment of the present invention applied to an automatic copying welding device.
【図５】前記実施形態で用いられている開先肩部・ビー
ドエッジ検出装置の基本的な構成を示すブロック図FIG. 5 is a block diagram showing a basic configuration of a grooved shoulder / bead edge detection device used in the embodiment.
【図６】本発明の方法によるビードエッジ検出例を示す
線図FIG. 6 is a diagram showing an example of bead edge detection according to the method of the present invention.
１０…鋼管断面の外面形状 １２…微小突起 １４…仮付溶接ビード部 １６…ビードエッジ ３０…鋼管 ３２…光学部 ３４…レーザスリット光 ３６…電荷結合素子 ３８…画像取得装置 ４０…開先肩部・ビードエッジ検出装置 ４６…溶接トーチ ４８…トーチ駆動用アクチュエータ ５０…直線当て嵌め回路 ５２…２乗残差計算回路 ５４…開先肩部・ビードエッジ判定回路 ５６…開先中心・ビード中心認識回路 10 ... Outer surface shape of steel pipe cross-section 12 ... Micro projection 14 ... Temporary welding bead part 16 ... Bead edge 30 ... Steel pipe 32 ... Optical part 34 ... Laser slit light 36 ... Charge coupled device 38 ... Image acquisition device 40 ... Groove shoulder part Bead edge detector 46 ... Welding torch 48 ... Torch drive actuator 50 ... Straight line fitting circuit 52 ... Square residual calculation circuit 54 ... Groove shoulder / bead edge determination circuit 56 ... Groove center / bead center recognition circuit
───────────────────────────────────────────────────── フロントページの続き (72)発明者 楠 光裕 千葉県千葉市中央区川崎町１番地 川崎製 鉄株式会社千葉製鉄所内 (72)発明者 井原 宏一 千葉県千葉市中央区川崎町１番地 川崎製 鉄株式会社千葉製鉄所内 (72)発明者 浦田 正男 千葉県千葉市中央区川崎町１番地 川鉄テ クノリサーチ株式会社千葉事業所内 (72)発明者 川西 昭 千葉県千葉市中央区川崎町１番地 川鉄情 報システム株式会社千葉事業所内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Mitsuhiro Kusunoki 1 Kawasaki-cho, Chuo-ku, Chiba, Chiba Prefecture Kawasaki Steel Co., Ltd. Chiba Works (72) Inventor Koichi Ihara 1 Kawasaki-cho, Chuo-ku, Chiba Chiba Steel Works Co., Ltd. Chiba Steel Works (72) Inventor Masao Urata 1 Kawasaki-cho, Chuo-ku, Chiba City, Chiba Prefecture Kawatetsu Techno-Research Corporation Chiba Works (72) Inventor Akira Kawanishi 1 Kawasaki-cho, Chuo-ku, Chiba City Kawatetsu Information System Co., Ltd. Chiba Office
Claims (2)
形状を検出し、該検出された断面形状から、開先肩部の
中心としての開先中心や、ビードエッジの中心としての
ビード中心を認識するための溶接開先・ビードの中心位
置検出方法において、 前記断面形状に沿って、直線又はＮ次多項式曲線を逐次
当て嵌めていき、 両者のずれが大きくなった時に、開先肩部又はビードエ
ッジと判定することを特徴とする溶接開先・ビードの中
心位置検出方法。1. A cross-sectional shape of a measurement object including a weld groove and a bead is detected, and a groove center as a center of a groove shoulder portion or a bead center as a center of a bead edge is detected from the detected cross-sectional shape. In the method for detecting the center position of the weld groove / bead for recognizing the above, a straight line or a polynomial curve of order N is successively fitted along the cross-sectional shape, and when the deviation between the two becomes large, the groove shoulder portion Alternatively, a method for detecting the center position of a weld groove / bead, which is characterized by determining a bead edge.
形状を検出する手段と、 検出された断面形状に沿って、直線又はＮ次多項式曲線
を、両者のずれが最小となるよう逐次当て嵌めていく手
段と、 当て嵌められた直線又はＮ次多項式曲線と断面形状との
ずれを計算する手段と、 該ずれが所定値以上となった時に、開先肩部又はビード
エッジと判定する手段と、 該判定結果に基づいて、開先肩部の中心としての開先中
心又はビードエッジの中心としてのビード中心を認識す
る手段と、 を備えたことを特徴とする溶接開先・ビードの中心位置
検出装置。2. A means for detecting a cross-sectional shape of a measuring object including a weld groove and a bead, and a straight line or an N-order polynomial curve is sequentially arranged along the detected cross-sectional shape so as to minimize the deviation between them. Means for fitting, means for calculating the deviation between the fitted straight line or polynomial curve of order N and the cross-sectional shape, and means for determining the groove shoulder or bead edge when the deviation exceeds a predetermined value And a means for recognizing the groove center as the center of the groove shoulder or the bead center as the center of the bead edge based on the determination result, and the center position of the weld groove / bead. Detection device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24896995A JP3151790B2 (en) | 1995-09-27 | 1995-09-27 | Method and apparatus for detecting center position of weld groove / bead |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP24896995A JP3151790B2 (en) | 1995-09-27 | 1995-09-27 | Method and apparatus for detecting center position of weld groove / bead |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0989524A true JPH0989524A (en) | 1997-04-04 |
| JP3151790B2 JP3151790B2 (en) | 2001-04-03 |
Family
ID=17186088
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP24896995A Expired - Fee Related JP3151790B2 (en) | 1995-09-27 | 1995-09-27 | Method and apparatus for detecting center position of weld groove / bead |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3151790B2 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2003093761A1 (en) * | 2002-04-30 | 2003-11-13 | Jfe Steel Corporation | Method and instrument for measuring bead cutting shape of electric welded tube |
| JP2009202180A (en) * | 2008-02-26 | 2009-09-10 | Toyota Motor Corp | Weld bead inspection method and weld bead inspection device |
| JP2010025818A (en) * | 2008-07-22 | 2010-02-04 | Toyota Motor Corp | Method and apparatus for inspecting welding bead |
| JP2010190797A (en) * | 2009-02-19 | 2010-09-02 | Jfe Steel Corp | Beveling section deepest position detection device and beveling section deepest position detection method |
| CN102441737A (en) * | 2010-08-30 | 2012-05-09 | 铃木株式会社 | Apparatus and method for determining shape of end of welding bead |
-
1995
- 1995-09-27 JP JP24896995A patent/JP3151790B2/en not_active Expired - Fee Related
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2003093761A1 (en) * | 2002-04-30 | 2003-11-13 | Jfe Steel Corporation | Method and instrument for measuring bead cutting shape of electric welded tube |
| US7236255B2 (en) | 2002-04-30 | 2007-06-26 | Jfe Steel Corporation | Method and instrument for measuring bead cutting shape of electric welded tube |
| US7471400B2 (en) | 2002-04-30 | 2008-12-30 | Jfe Steel Corporation | Measurement method and device for bead cutting shape in electric resistance welded pipes |
| US7619750B2 (en) | 2002-04-30 | 2009-11-17 | Jfe Steel Corporation | Measurement method and device for bead cutting shape in electric resistance welded pipes |
| JP2009202180A (en) * | 2008-02-26 | 2009-09-10 | Toyota Motor Corp | Weld bead inspection method and weld bead inspection device |
| JP2010025818A (en) * | 2008-07-22 | 2010-02-04 | Toyota Motor Corp | Method and apparatus for inspecting welding bead |
| JP2010190797A (en) * | 2009-02-19 | 2010-09-02 | Jfe Steel Corp | Beveling section deepest position detection device and beveling section deepest position detection method |
| CN102441737A (en) * | 2010-08-30 | 2012-05-09 | 铃木株式会社 | Apparatus and method for determining shape of end of welding bead |
| US8946595B2 (en) | 2010-08-30 | 2015-02-03 | Suzuki Motor Corporation | Apparatus and method for determining shape of end of welding bead |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3151790B2 (en) | 2001-04-03 |
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