JP2004085515A - Method of detecting shape of pipeline using impulse response - Google Patents

Method of detecting shape of pipeline using impulse response Download PDF

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Publication number
JP2004085515A
JP2004085515A JP2002289236A JP2002289236A JP2004085515A JP 2004085515 A JP2004085515 A JP 2004085515A JP 2002289236 A JP2002289236 A JP 2002289236A JP 2002289236 A JP2002289236 A JP 2002289236A JP 2004085515 A JP2004085515 A JP 2004085515A
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Japan
Prior art keywords
pipeline
impulse response
sound wave
pipe
shape
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JP2002289236A
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Japanese (ja)
Inventor
Hiroshi Nakajima
中島 弘史
Shinji Oohashi
大橋 心耳
Hideo Tsuru
鶴 秀生
Hiroshi Oyama
大山 宏
Takaaki Yamanaka
山中 高章
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Nittobo Acoustic Engineering Co Ltd
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Nittobo Acoustic Engineering Co Ltd
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Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that skillfulness and long-time work are required at the time of moving a mobile camera in an easily visible direction or to a position and, when the shape of a pipeline is detected by using the reflected sound of an impulse response of the pipeline, the sound is attenuated and produces accents as the sound goes to the deep portion of the pipeline and the detection of each portion of the pipeline becomes difficult due to the attenuation and the type of the portion is not discriminated due to the accents, because each portion is detected from the impulse response of the pipeline itself. <P>SOLUTION: In this method, a sound wave is inputted to the pipeline composed of a straight portion, and a special shape portion from one side and the length and shape of the pipeline from the side to the other side are detected by receiving reflected sound waves from the special shape portion. In addition, the shape detection of the pipeline comprises a step of modeling the straight and special shape portions of the pipeline by receiving the reflected waves as the impulse response of the pipeline, a step of calculating the impulse response of each portion by estimating the impulse response of the pipeline by calculating the modeled straight and special shape portions of the pipeline, and a step of successively detecting the shape of the pipeline from one side by comparing the impulse response of each portion with the impulse response of the pipeline from which the reflected sound waves are received. <P>COPYRIGHT: (C)2004,JPO

Description

【0001】
【発明の属する技術分野】
本発明は、管路の一方から入力音波を入力させ、入力音波を異形状部位に反射させた反射音波を受信して管路のインパルス応答を得て、管路のインパルス応答を予め計算により推定した各部位のインパルス応答と比較することにより、管路内の各異形状部位で測定した反射音波の管路のインパルス応答を管路の一方に近い部分から順次推定して管路の直管部位と異形状部位の長さと位置と種類の特定を行うインパルス応答による管路形状検出方法に関するものである。
【0002】
【従来の技術】
従来、この種の管路の形状の検出を行う方法は、管路の一端から移動式の小型カメラや照明器具を挿入して外部でモニターをオペレータが視覚的に目視しながら行うものと、管路の一端にスピーカーとマイクロホンを備えてインパルス応答の反射音で行うものとがあった。
【0003】
【発明が解決しようとする課題】
然し乍ら、移動式の小型カメラを用いるものは、管路の形状が複雑な場合や上下に屈曲している場合、移動式のカメラを目視し易い方向や位置に移動させることに熟練を要すと共に手間暇係る作業と成っており、又、インパルス応答の反射音で行うものは、単に管路のインパルス応答そのものから各部位を検出するものであって、各部位が奥に行くほど手前の部位を通過することによって反射音に減衰となまりが生じ、減衰により反射音の検出が困難で、加えて、なまりによって反射音からの部位の種別が判断することができなくなっていた。
【0004】
【課題を解決するための手段】
本発明は、前述の課題に鑑み、研鑽の結果、反射音波を管路のインパルス応答として受信して管路の直管部位と異形状部位をモデル化する過程と、モデル化した管路の直管部位と異形状部位とを計算によって管路のインパルス応答を推定して各部位のインパルス応答を算出する過程と、各部位のインパルス応答と反射音波を受信した管路のインパルス応答とを比較して管路の一方からの形状を順次検出する過程とから構成されるものである。
【0005】
【作用】
本発明のインパルス応答による管路形状検出方法は、直管部位と異形状部位とから成る管路の一端部からスピーカーにより入力音波を入力して、マイクロホンにより異形状部位で反射した反射音波を受信させ、受信した反射音波を管路のインパルス応答としてモデル化すると共に、モデル化した管路の直管部位と異形状部位とを予め計算によって各部位のインパルス応答を算出し、算出した各部位のインパルス応答と反射音波を受信した実際の管路のインパルス応答とを比較して管路の一方からの形状を順次検出するものである。
【0006】
従って、本発明の目的は、管路の一方にスピーカーとマイクロホンを備え、音波を入力すると共に反射する音波を捕らえ、予め計算により算出した各部位のインパルス応答と実際の管路のインパルス応答とを比較して、管路の全体の形状を検出する方法を提供するものである。
【0007】
【発明の実施の形態】
以下、本発明のインパルス応答による管路形状検出方法について順次図面を参照して具体的に説明する。
【0008】
図1は本発明のインパルス応答による管路形状検出方法の測定部の説明図であり、図2は本発明のインパルス応答による管路形状検出方法の実際の管路とモデル化した状態の説明図であり、図3は本発明のインパルス応答による管路形状検出方法の直管部位と異形状部位のインパルス応答の推定の説明図であり、図4はインパルス応答による管路形状検出方法の各部位のインパルス応答の過程の説明図である。
【0009】
本発明は、管路1の一方から入力音波を入力させ、入力音波を異形状部位Rに反射させた反射音波を受信して管路のインパルス応答を得て、管路のインパルス応答を予め計算により推定した各部位のインパルス応答と比較することにより、管路1内の各異形状部位Rで反射した反射音波の管路のインパルス応答を管路1の一方に近い部分から順次推定して管路の直管部位Lと異形状部位Rの長さと位置と種類の特定を行う管路のインパルス応答による管路形状検出方法に関するものであり、直管部位Lと異形状部位Rとから成る管路1の一方から入力音波を入力させ、該入力音波が異形状部位Rにより反射してくる反射音波を受信して管路1の他方までの長さと形状を検出する方法であって、前記反射音波を管路のインパルス応答として受信して管路1の直管部位Lと異形状部位Rをモデル化する過程と、該モデル化した管路の直管部位Lと異形状部位Rとを計算によって管路のインパルス応答を推定して各部位のインパルス応答を算出する過程と、該各部位のインパルス応答と前記反射音波を受信した管路のインパルス応答とを比較して管路1の一方からの形状を順次検出する過程とから構成されるものである。
【0010】
先ず、本発明のインパルス応答による管路形状検出方法は、図1に図示する如く、形状を検出する管路1の一方に入力音波を発信させるスピーカ2と反射音波を受信するマイクロホン3を設置するものである。
【0011】
そして、図2(A)に図示する実際の管路1の直管部位L1〜L5及び異形状部位R1〜R5をモデル化させるものであり、直管部位L1〜L5と異形状部位R1〜R5とが相互に接続された管路1であり、異形状部位R1は曲がり部、異形状部位R2は分岐部、異形状部位R3は管端部、異形状部位R4は継手部、異形状部位R5は管端部であり、マイクロホンの受信した反射音波の観測信号として管路のインパルス応答によりモデル化すると図2(B)に図示するように表れるものである。
【0012】
次いで、図3(A)に図示するものは、直管部位L1〜L5での計算によって算出する各部位のインパルス応答の直管部位L1〜L5の長さ方向のモードのみの一例であり、パラメータは長さ1と伝達速度cと伝達減衰率β(ω)があり、これらによって直管部位L1〜L5の音波はP(x,t)を次の数1で表現するもので、Pi(x,t)は入力音波であり、Pr(x,t)は反射音波である。
【0013】
【数1】

Figure 2004085515
【0014】
そして、Pi(x,t)とPr(x,t)とのフーリエ変換を夫々Pi(x,ω)とPr(x,ω)とすると、次の数2及び数3で求めることができるものであり、Pi(O,ω)は一方側での入力音波の周波数特性であり、Pr(L,ω)は他方側の受信音波の周波数特性である。
【0015】
【数2】
Figure 2004085515
【0016】
【数3】
Figure 2004085515
【0017】
次に、一方側で測定した反射音波の管路のインパルス応答の周波数特性をH(ω)とすれば、次の数4と成るものである。
【0018】
【数4】
Figure 2004085515
【0019】
Figure 2004085515
▼(ω)とすれば、次の数5と成るものであり、各パラメーター値が決まればH(ω)から算出できるものである。
【0020】
【数5】
Figure 2004085515
【0021】
尚、実際の推定時には直管部位の長さ1は初期反射音波の時間遅延から推定し、伝達速度cと伝達減哀率β(ω)は予め測定によって求めておいた値を用いるものである。
【0022】
そして、図3(B)に図示するものは、異形状部位R1〜R5での計算によって算出する各部位のインパルス応答の異形状部位R1〜R5の長さ方向のモードのみの一例であり、パラメータは伝達行列Mであり、伝達行列Mは次の数6により求めるものである。
【0023】
【数6】
Figure 2004085515
【0024】
そして、手前の直管部位Lmから異形状部位Rに入力する音波が次の直管部位Lnに出て行く音波となる伝達率rmn(ω)を要素とする行列であり、これを用いて、異形状部位Rに入力する音波又は出力する音波の関係は次の数7で与えられるものであり、ここでPni(ω)及びPnr(ω)は夫々直管部位Lnから異形状部位Rに入ってくる音波及び出て行く音波である。
【0025】
【数7】
Figure 2004085515
【0026】
実際に各部位のインパルス応答の場合は、直管部位L1の音波が既知で直管部位L2の音波が不明であるので、直管部位L2についての整理は次の数8で算出されるものである。
【0027】
【数8】
Figure 2004085515
【0028】
そして、異形状部位Rの手前で測定した管路のインパルス応答の周波数特性をH(ω)とすれば、次の数9の関係が成立するものである。
【0029】
【数9】
Figure 2004085515
【0030】
次いで、これを数7に代入すれば、次の数10と成るものである。
【0031】
【数10】
Figure 2004085515
【0032】
そして、数8により、次の数11及び数12と成るものである。
【数11】
Figure 2004085515
【0033】
【数12】
Figure 2004085515
【0034】
Figure 2004085515
の数13と成るもので、パラメータの伝達行列Mが決まればH(ω)から算出が可能となるものである。
【0035】
【数13】
Figure 2004085515
【0036】
実際の各部位のインパルス応答時では反射波形から異形状部位Rを判断した後、予め測定によって求めておいた伝達行列Mの値を用いるものである。
【0037】
次いで、管路のインパルス応答の逐次推定および異形状部位Rの検出は、図4に図示の如く、管路のインパルス応答の逐次推定法において1回の手順を示したものであり、図4(A)に図示するように、管路のインパルス応答hn(t)の初期反射音波の遅延時間から直管部位Lの長さ1を推定するものである。
【0038】
次に、図4(B)に図示するように、直管部位Lの長さ1に加えて、予め、測定によって求めていた伝達速度cと伝達減衰率β(ω)を用いて直管部位Lの先からの管路のイン
Figure 2004085515
って反射音波の遅延と減衰・なまりが除去されるものである。
【0039】
そして、図4(B)に図示するように、初期反射音から異形状部位Rの判別を行うものであり、初期反射音波は後方の各部位の影響を受けないため、単純なパターンマッチングにより異形状部位Rの判別が可能なものである。
【0040】
つまり、特定した異形状部位Rの伝達行列Mを予め測定によって得たデータから参照し、
Figure 2004085515
答hn+1(t)を推定するものである。
【0041】
これにより、図4(C)に図示ように、異形状部位Rによって発生する反射音波や、その異形状部位Rの伝達により発生した波形のなまりや多重反射の影響が除去されるものであり、図4(A)(B)(C)を繰り返して行うことにより、異形状部位R1〜R5と直管部位L1〜L5とのパラメータが管路1の一方に近い位置から順に得られるものであり、異形状部位R1〜R5が管路1の他方が得られるまで繰り返し行うことなより管路1の全ての長さや形状の検出が可能となるものである。
【0042】
尚、本発明の実施の形態では、管路1の長さ方向の音波のみを記載しているものであるが、他の方向の音波についても、ベクトル及び行列の次元を拡張することによって可能なもので、この場合、反射音波から異形状部位Rを判別する際に、複数の方向の反射音波の波形を用いてパターンマッチングが可能なため、異形状部位Rの判別の精度が向上てきるものである。
【0043】
又、本発明の実施の形態では、異形状部位Rとして、直管部位Lが1つしか接続しない管端や、3方向に分岐する分岐管の異形状部位Rについては記載していないが、伝達行列Mの次元を変えることにより可能なものであるが、分岐管の異形状部位Rの場合は、1つの直管部位Lからのインパルス応答から、2つの直管部位Lの夫々の管路のインパルス応答を一意に決定することができないことから、複数方向のモードの反射音情報などから、どちらの直管部位Lによる反射音波なのかを判別する必要があるものである。
【0044】
尚、本発明の前述の実施の形態では管路の一方から入力音波を入力させるとしているが、管路の端部でだけでは無く、管路の途中から入力音波を入力させてインパルス応答を受信することも可能なものである。
【0045】
【発明の効果】
前述のことから、本発明のインパルス応答による管路形状検出方法は、直管部位と異形状部位とから成る管路の一方からスピーカーにより入力音波を入力して、マイクロホンにより異形状部位で反射した反射音波を受信させ、受信した反射音波を管路のインパルス応答としてモデル化すると共に、モデル化した管路の直管部位と異形状部位とを予め計算によって各部位のインパルス応答を算出し、算出した各部位のインパルス応答と反射音波を受信した実際の管路のインパルス応答とを比較して管路の一方からの形状を順次検出するもので、簡易な装置と方法で埋設管等の管路の長さや形状を検出することを可能としたものであり、画期的で実用性の高い発明である。
【図面の簡単な説明】
【図1】図1は本発明のインパルス応答による管路形状検出方法の測定部の説明図である。
【図2】図2は本発明のインパルス応答による管路形状検出方法の実際の管路とモデル化した状態の説明図である。
【図3】図3は本発明のインパルス応答による管路形状検出方法の直管部位と異形状部位の管路のインパルス応答の推定の説明図である。
【図4】図4は管路のインパルス応答による管路形状検出方法の各部位のインパルス応答の過程の説明図である。
【符号の説明】
1   管路
2   スピーカー
3   マイクロホン
L   直管部位
R   異形状部位[0001]
TECHNICAL FIELD OF THE INVENTION
According to the present invention, an input sound wave is input from one of the pipes, a reflected sound wave obtained by reflecting the input sound wave to a deformed portion is received, an impulse response of the pipe is obtained, and an impulse response of the pipe is estimated by calculation in advance. By comparing with the impulse response of each part, the impulse response of the pipe of the reflected sound wave measured at each of the irregularly shaped parts in the pipe is sequentially estimated from a portion near one side of the pipe, and the straight pipe part of the pipe is estimated. And a pipe shape detection method based on an impulse response for specifying the length, position and type of an irregularly shaped portion.
[0002]
[Prior art]
Conventionally, methods for detecting the shape of this type of pipeline include a method in which a small mobile camera or a lighting fixture is inserted from one end of the pipeline and an operator visually observes a monitor externally, There is a method in which a speaker and a microphone are provided at one end of a road to perform reflected sound of an impulse response.
[0003]
[Problems to be solved by the invention]
However, a camera using a mobile small camera requires skill in moving the mobile camera to a direction and a position that is easy to see when the shape of the conduit is complicated or bent up and down. Work that involves time and effort is performed, and what is performed with the reflected sound of the impulse response is simply to detect each part from the impulse response itself of the pipeline, and the more the part goes, the more the part nearer The passing causes attenuation and dulling of the reflected sound, and the attenuation makes it difficult to detect the reflected sound. In addition, the dulling makes it impossible to determine the type of the part from the reflected sound.
[0004]
[Means for Solving the Problems]
The present invention has been made in view of the above-described problems, and as a result of study, a process of receiving a reflected sound wave as an impulse response of a pipeline to model a straight pipe portion and an irregularly-shaped portion of the pipeline, and a process of directly modeling the modeled pipeline. The process of calculating the impulse response of each part by estimating the impulse response of the pipe by calculating the pipe part and the deformed part is compared with the impulse response of each part and the impulse response of the pipe that received the reflected sound wave. And sequentially detecting the shape from one side of the pipeline.
[0005]
[Action]
The pipe shape detection method using an impulse response according to the present invention is configured such that an input sound wave is input from one end of a pipe line including a straight pipe portion and a deformed portion by a speaker, and a reflected sound wave reflected by the microphone is received by the microphone. The received reflected sound wave is modeled as an impulse response of the pipeline, and the impulse response of each site is calculated in advance by calculating the straight pipe portion and the deformed portion of the modeled pipeline, and the calculated impulse response of each portion is calculated. The impulse response is compared with the impulse response of the actual pipeline receiving the reflected sound wave, and the shape from one side of the pipeline is sequentially detected.
[0006]
Therefore, an object of the present invention is to provide a speaker and a microphone on one side of a pipeline, capture a reflected acoustic wave while inputting a acoustic wave, and calculate an impulse response of each part calculated in advance and an impulse response of an actual pipeline. In comparison, it provides a method for detecting the overall shape of the conduit.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, a pipe shape detection method using an impulse response according to the present invention will be described in detail with reference to the accompanying drawings.
[0008]
FIG. 1 is an explanatory view of a measuring section of a pipe shape detection method using an impulse response according to the present invention, and FIG. 2 is an explanatory diagram of an actual pipe and a modeled state of the pipe shape detecting method using an impulse response of the present invention. FIG. 3 is an explanatory diagram of the estimation of the impulse response of the straight pipe portion and the irregularly shaped portion of the pipe shape detection method using the impulse response according to the present invention, and FIG. FIG. 4 is an explanatory diagram of a process of an impulse response of FIG.
[0009]
According to the present invention, an input sound wave is input from one of the pipes 1, a reflected sound wave obtained by reflecting the input sound wave to the deformed portion R is received, an impulse response of the pipe is obtained, and an impulse response of the pipe is calculated in advance. By comparing with the impulse response of each part estimated by the above, the impulse response of the pipeline of the reflected sound wave reflected at each of the irregularly shaped portions R in the pipeline 1 is sequentially estimated from a portion close to one side of the pipeline 1 and The present invention relates to a pipe shape detection method for determining the length, position, and type of a straight pipe portion L and a deformed portion R by using an impulse response of a pipe. A method of inputting an input sound wave from one of the channels 1, receiving the reflected sound wave reflected from the irregularly shaped portion R, and detecting the length and shape of the pipe 1 to the other end, wherein the reflection is performed. Receives sound waves as the impulse response of the pipeline Modeling the straight pipe portion L and the deformed portion R of the pipe 1 and calculating the impulse response of the pipe line by calculating the straight pipe portion L and the deformed portion R of the modeled pipe. A step of calculating an impulse response of each part and a step of comparing the impulse response of each part with the impulse response of the pipe that has received the reflected sound wave and sequentially detecting the shape from one of the pipes 1 Is what is done.
[0010]
First, according to the pipe shape detection method based on the impulse response of the present invention, as shown in FIG. 1, a speaker 2 for transmitting an input sound wave and a microphone 3 for receiving a reflected sound wave are installed in one of the pipe lines 1 for detecting the shape. Things.
[0011]
Then, the straight pipe portions L1 to L5 and the deformed portions R1 to R5 of the actual pipeline 1 shown in FIG. 2A are modeled, and the straight pipe portions L1 to L5 and the deformed portions R1 to R5 are modeled. Are connected to each other, the deformed portion R1 is a bent portion, the deformed portion R2 is a branch portion, the deformed portion R3 is a pipe end, the deformed portion R4 is a joint portion, and the deformed portion R5. Is the end of the tube, which appears as shown in FIG. 2B when it is modeled by the impulse response of the tube as an observation signal of the reflected sound wave received by the microphone.
[0012]
Next, what is illustrated in FIG. 3A is an example of only the mode in the length direction of the straight pipe parts L1 to L5 of the impulse response of each part calculated by calculation at the straight pipe parts L1 to L5. Has a length 1, a transmission speed c, and a transmission attenuation rate β (ω), and the sound waves at the straight pipe portions L1 to L5 express P (x, t) by the following equation 1, and Pi (x , T) is an input sound wave, and Pr (x, t) is a reflected sound wave.
[0013]
(Equation 1)
Figure 2004085515
[0014]
If the Fourier transforms of Pi (x, t) and Pr (x, t) are Pi (x, ω) and Pr (x, ω), respectively, those can be obtained by the following equations 2 and 3. Where Pi (O, ω) is the frequency characteristic of the input sound wave on one side, and Pr (L, ω) is the frequency characteristic of the received sound wave on the other side.
[0015]
(Equation 2)
Figure 2004085515
[0016]
[Equation 3]
Figure 2004085515
[0017]
Next, assuming that the frequency characteristic of the impulse response of the conduit of the reflected sound wave measured on one side is H (ω), the following equation 4 is obtained.
[0018]
(Equation 4)
Figure 2004085515
[0019]
Figure 2004085515
If ▼ (ω), the following equation 5 is obtained, and if each parameter value is determined, it can be calculated from H (ω).
[0020]
(Equation 5)
Figure 2004085515
[0021]
At the time of actual estimation, the length 1 of the straight pipe portion is estimated from the time delay of the initial reflected sound wave, and the transmission speed c and the transmission attenuation ratio β (ω) use values obtained by measurement in advance. .
[0022]
FIG. 3B is an example of only the mode in the length direction of the irregularly shaped portions R1 to R5 of the impulse response of each portion calculated by calculation at the irregularly shaped portions R1 to R5. Is a transfer matrix M. The transfer matrix M is obtained by the following equation (6).
[0023]
(Equation 6)
Figure 2004085515
[0024]
Then, a matrix having a transmissivity rmn (ω) as an element, in which a sound wave input from the front straight pipe portion Lm to the deformed portion R becomes a sound wave going out to the next straight pipe portion Ln, is used. The relationship between sound waves input to or output from the irregularly shaped portion R is given by the following equation 7, where Pni (ω) and Pnr (ω) enter the irregularly shaped portion R from the straight pipe portion Ln, respectively. Coming sound waves and outgoing sound waves.
[0025]
(Equation 7)
Figure 2004085515
[0026]
Actually, in the case of the impulse response of each part, since the sound wave of the straight pipe part L1 is known and the sound wave of the straight pipe part L2 is unknown, the arrangement of the straight pipe part L2 is calculated by the following equation 8. is there.
[0027]
(Equation 8)
Figure 2004085515
[0028]
If the frequency characteristic of the impulse response of the pipeline measured before the irregularly shaped portion R is H (ω), the following equation 9 holds.
[0029]
(Equation 9)
Figure 2004085515
[0030]
Then, when this is substituted into Expression 7, the following Expression 10 is obtained.
[0031]
(Equation 10)
Figure 2004085515
[0032]
Then, the following Expression 11 and Expression 12 are obtained from Expression 8.
[Equation 11]
Figure 2004085515
[0033]
(Equation 12)
Figure 2004085515
[0034]
Figure 2004085515
When the transfer matrix M of the parameter is determined, it can be calculated from H (ω).
[0035]
(Equation 13)
Figure 2004085515
[0036]
At the time of the actual impulse response of each part, the irregular shape part R is determined from the reflection waveform, and then the value of the transfer matrix M obtained in advance by measurement is used.
[0037]
Next, as shown in FIG. 4, the sequential estimation of the impulse response of the pipeline and the detection of the irregularly shaped portion R show one procedure in the sequential estimation method of the impulse response of the pipeline, as shown in FIG. As shown in A), the length 1 of the straight pipe portion L is estimated from the delay time of the initial reflected sound wave of the impulse response hn (t) of the pipeline.
[0038]
Next, as shown in FIG. 4B, in addition to the length 1 of the straight pipe part L, the straight pipe part L is calculated using the transmission speed c and the transmission attenuation rate β (ω) obtained in advance by measurement. In the pipeline from the end of L
Figure 2004085515
Thus, the delay, attenuation and rounding of the reflected sound wave are removed.
[0039]
Then, as shown in FIG. 4 (B), the differently shaped portion R is determined from the initial reflected sound, and the initial reflected sound wave is not affected by the rear portions. The shape portion R can be determined.
[0040]
That is, the transfer matrix M of the specified irregular-shaped portion R is referred to from data obtained by measurement in advance,
Figure 2004085515
The answer hn + 1 (t) is estimated.
[0041]
Thereby, as shown in FIG. 4C, the reflected sound wave generated by the irregularly shaped portion R, the rounding of the waveform generated by the transmission of the irregularly shaped portion R, and the effect of multiple reflection are removed. By repeatedly performing FIGS. 4A, 4B, and 4C, the parameters of the irregularly shaped portions R1 to R5 and the straight pipe portions L1 to L5 can be obtained in order from a position near one of the pipelines 1. The length and shape of the entire pipeline 1 can be detected by repeating the process until the other of the irregularly shaped portions R1 to R5 is obtained.
[0042]
In the embodiment of the present invention, only the sound wave in the longitudinal direction of the pipe 1 is described. However, sound waves in other directions can be obtained by expanding the dimensions of the vector and the matrix. In this case, when determining the deformed portion R from the reflected sound wave, pattern matching can be performed using the waveforms of the reflected sound waves in a plurality of directions, so that the accuracy of determining the deformed portion R is improved. It is.
[0043]
Further, in the embodiment of the present invention, as the deformed portion R, a pipe end to which only one straight pipe portion L is connected and a deformed portion R of a branch pipe branched in three directions are not described. Although it is possible by changing the dimension of the transfer matrix M, in the case of the irregularly shaped portion R of the branch pipe, the respective conduits of the two straight pipe portions L are obtained from the impulse response from one straight pipe portion L. Since the impulse response cannot be uniquely determined, it is necessary to determine which straight pipe portion L is the reflected sound wave from the reflected sound information in a plurality of modes.
[0044]
In the above-described embodiment of the present invention, the input sound wave is input from one side of the pipe, but the impulse response is received by inputting the input sound wave not only at the end of the pipe but also in the middle of the pipe. It is also possible.
[0045]
【The invention's effect】
As described above, in the pipe shape detection method using the impulse response of the present invention, an input sound wave is input from one of the pipes formed of a straight pipe portion and a deformed portion by a speaker, and reflected by the microphone at the deformed portion. Receiving the reflected sound wave, modeling the received reflected sound wave as an impulse response of the pipeline, calculating the impulse response of each part by calculating in advance the straight pipe part and the deformed part of the modeled pipeline, and calculating It compares the impulse response of each part and the impulse response of the actual pipe line that has received the reflected sound wave, and sequentially detects the shape from one side of the pipe line. It is a revolutionary and highly practical invention that makes it possible to detect the length and shape of the object.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram of a measurement unit of a pipe shape detection method using an impulse response according to the present invention.
FIG. 2 is an explanatory diagram of an actual pipeline and a modeled state of the pipeline shape detection method using an impulse response according to the present invention.
FIG. 3 is an explanatory diagram for estimating an impulse response of a pipe at a straight pipe portion and a pipe portion of an irregular shape in the pipe shape detection method using an impulse response of the present invention.
FIG. 4 is an explanatory diagram of a process of an impulse response of each part in a pipeline shape detection method based on a pipeline impulse response.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Pipeline 2 Speaker 3 Microphone L Straight pipe part R Irregular part

Claims (1)

直管部位と異形状部位とから成る管路の一方から入力音波を入力させ、該入力音波が異形状部位により反射してくる反射音波を受信して管路の他方までの長さと形状を検出する方法であって、前記反射音波を管路のインパルス応答として受信して管路の直管部位と異形状部位をモデル化する過程と、該モデル化した管路の直管部位と異形状部位とを計算によって管路のインパルス応答を推定して各部位のインパルス応答を算出する過程と、該各部位のインパルス応答と前記反射音波を受信した管路のインパルス応答とを比較して管路の一方からの形状を順次検出する過程とから構成されることを特徴とするインパルス応答による管路形状検出方法。An input sound wave is input from one of the conduits composed of a straight pipe portion and a deformed portion, and the input sound wave receives a reflected sound wave reflected by the deformed portion and detects the length and shape to the other end of the conduit. A method of receiving the reflected sound wave as an impulse response of a pipeline to model a straight pipe portion and a deformed portion of the pipeline, and a process of modeling the straight pipe portion and the deformed portion of the modeled pipeline. The process of estimating the impulse response of the pipe by calculating the impulse response of each part, and comparing the impulse response of each part with the impulse response of the pipe that has received the reflected sound wave. A method of sequentially detecting a shape from one side.
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009503492A (en) * 2005-07-29 2009-01-29 アコースティックアイ エルティディー. Non-destructive inspection system and method for tubular systems
JP2010519509A (en) * 2007-02-19 2010-06-03 ネーデルランデ オルガニサチエ ヴォール トエゲパスト−ナツールウェテンスハペリエク オンデルゾエク ティーエヌオー Ultrasonic surface monitoring method
GB2519142A (en) * 2013-10-11 2015-04-15 Univ Manchester Signal processing system and method
CN106949860A (en) * 2017-05-15 2017-07-14 山东省科学院激光研究所 Inner-walls of duct detecting system and method

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009503492A (en) * 2005-07-29 2009-01-29 アコースティックアイ エルティディー. Non-destructive inspection system and method for tubular systems
JP2010519509A (en) * 2007-02-19 2010-06-03 ネーデルランデ オルガニサチエ ヴォール トエゲパスト−ナツールウェテンスハペリエク オンデルゾエク ティーエヌオー Ultrasonic surface monitoring method
US8583407B2 (en) 2007-02-19 2013-11-12 Nederlandse Organisatie Voor Toegepast-Natuurwetenschappelijk Onderzoek Tno Ultrasonic surface monitoring
GB2519142A (en) * 2013-10-11 2015-04-15 Univ Manchester Signal processing system and method
GB2519142B (en) * 2013-10-11 2016-09-28 Univ Manchester Signal processing system and method
US10168302B2 (en) 2013-10-11 2019-01-01 The University Of Manchester Signal processing system and methods
CN106949860A (en) * 2017-05-15 2017-07-14 山东省科学院激光研究所 Inner-walls of duct detecting system and method

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