US-12626386-B2 - Bending angle determining method and determining device

US12626386B2US 12626386 B2US12626386 B2US 12626386B2US-12626386-B2

Abstract

Achieved is a determination method which enables accurate determination as to a bending angle. A bending angle determination method includes: an input reception step of receiving, with respect to a joint at which a first pipe and a second pipe are joined together, inputs of respective parameters of a plurality of predetermined positions set in a circumferential direction of the first pipe; and a bending angle determination step of determining whether a bending angle at the joint is appropriate, on the basis of the parameters that have been inputted in the input reception step.

Inventors

Yasushi IDOMOTO
Kazuma HARADA

Assignees

KUBOTA CORPORATION

Dates

Publication Date: 20260512
Application Date: 20220425
Priority Date: 20210521

Claims (4)

1 . A bending angle determination method performed by one or more processors comprising: an input reception step of receiving, with respect to a joint at which a spigot of a first pipe is inserted into a socket of a second pipe so as to join the first pipe and the second pipe together, inputs of respective parameters of a plurality of predetermined positions set in a circumferential direction of the first pipe, the parameters each indicating a degree to which the first pipe is inserted into the second pipe; a bending angle determination step of determining, on the basis of the parameters that have been inputted in the input reception step, whether a bending angle at the joint is appropriate; an image capturing step of capturing an image of the joint; a derivation step of deriving, from the image, laving direction straight lines corresponding to respective laying directions of the pipes; and a calculability determination step of determining whether the bending angle is calculable on the basis of the laying direction straight lines, wherein, the input reception step and the bending angle determination step are carried out in a case where it has been determined in the calculability determination step that the bending angle is not calculable, and in the bending angle determination step, when at least a portion of the region of the first pipe and the region of the second pipe in the image is present outside a predetermined range, it is determined that the bending angle is not calculable; further including a contour extraction step for extracting contours of the first pipe and the second pipe, in the contour extraction step, generating an image in which only the respective regions of the first pipe and the second pipe are extracted, extracting the contours of the respective regions as the contours of the first pipe and the second pipe from the generated image, and in the derivation step, defining a plurality of straight lines each crossing a contour of a side-surface of the first pipe and the second pipe at two points, deriving intermediate points between the two points at which the plurality of straight lines cross the contour of the side-surface, deriving an approximate intermediate line approximating the set of the intermediate points, and deriving a straight line approximating the set of the intermediate points that are present within a predetermined distance from the approximate intermediate line as the laying direction straight line.
2 . The bending angle determination method according to claim 1 , further comprising an auxiliary calculation step of calculating the bending angle on the basis of the parameters.
3 . A bending angle determination apparatus comprising one or more processors configured to execute computer-readable instructions to: receive, with respect to a joint at which a spigot of a first pipe is inserted into a socket of a second pipe so as to join the first pipe and the second pipe together, inputs of respective parameters of a plurality of predetermined positions set in a circumferential direction of the first pipe, the parameters each indicating a degree to which the first pipe is inserted into the second pipe; and determine, on the basis of the parameters that have been inputted into and received by the one or more processors, whether a bending angle at the joint is appropriate; capture an image of the joint; derive, from the image, laving direction straight lines corresponding to respective laying directions of the pipes; and determine whether the bending angle is calculable on the basis of the laving direction straight lines, wherein receiving the inputs of the respective parameters and determining whether the bending angle is appropriate are carried out in a case where it has been determined that the bending angle is not calculable, and when at least a portion of the region of the first pipe and the region of the second pipe in the image is present outside a predetermined range, it is determined that the bending angle is not calculable.
4 . The bending angle determination apparatus according to claim 3 , wherein the one or more processors are further configured to execute computer readable instructions to: calculate the bending angle on the basis of the parameters; enable displaying of the parameters and the bending angle on a single screen; extract contours of the first pipe and the second pipe, generate an image in which only respective regions of the first pipe and the second pipe are extracted, and extract the contours of the respective regions as the contours of the first pipe and the second pipe, and define a plurality of straight lines each crossing a contour of a side-surface of the first pipe and the second pipe at two points, deriving intermediate points between the two points at which the plurality of straight lines cross the contour of the side-surface, deriving an approximate intermediate line approximating the set of the intermediate points, and deriving a straight line approximating the set of the intermediate points that are present within a predetermined distance from the approximate intermediate line as the laving direction straight line.

Description

TECHNICAL FIELD The present invention relates to a calculation method and a calculation apparatus each for calculating a bending angle at a joining place where pipes are joined together. BACKGROUND ART At a joining place where pipes are joined together, the pipes need to be joined so that a bending angle between the pipes is within a permissible range. Examples of a method for determining whether the bending angle is within a permissible range include a method that uses the calculation method disclosed in Non-Patent Literature 1 to calculate a bending angle and makes determination. According to the calculation method, a distance between (a) a white line drawn on a circumferential surface of one of pipes and (b) an end surface of the other of the pipes is measured at a plurality of positions in a circumferential direction of the pipes, so that a bending angle is calculated by (i) a difference between a maximum value and a minimum value of the distance and (ii) a nominal diameter of the pipes. CITATION LIST Non-Patent Literature [Non-patent Literature 1]Japan Ductile Iron Pipe Association, “T-gata dakutairu tekkan setsugou youryousho [T-shaped Ductile Iron Pipe Joint Procedure Specification]”, p. 21-22 SUMMARY OF INVENTION Technical Problem Another possible method for making determination as to a bending angle is, for example, a method that performs calculation and determination based on an image of the joining place where the pipes are joined together. However, according to this method, there is a possibility that the bending angle cannot be properly calculated, depending on, for example, a condition under which the image is captured. It is an object of an aspect of the present invention to achieve, for example, a method that enables more accurate determination as to a bending angle. Solution to Problem In order to solve the foregoing problem, a bending angle determination method in accordance with an aspect of the present invention includes: an input reception step of receiving, with respect to a joint at which a spigot of a first pipe is inserted into a socket of a second pipe so as to join the first pipe and the second pipe together, inputs of respective parameters of a plurality of predetermined positions set in a circumferential direction of the first pipe, the parameters each indicating a degree to which the first pipe is inserted into the second pipe; and a bending angle determination step of determining, on the basis of the parameters that have been inputted in the input reception step, whether a bending angle at the joint is appropriate. Further, a bending angle determination apparatus in accordance with an aspect of the present invention includes: an input reception section configured to receive, with respect to a joint at which a spigot of a first pipe is inserted into a socket of a second pipe so as to join the first pipe and the second pipe together inputs of respective parameters of a plurality of predetermined positions set in a circumferential direction of the first pipe, the parameters each indicating a degree to which the first pipe is inserted into the second pipe; and a bending angle determination section configured to determine, on the basis of the parameters that have been inputted into and received by the input reception section, whether a bending angle at the joint is appropriate. Advantageous Effects of Invention An aspect of the present invention makes it possible to more accurately perform determination as to a bending angle. BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a flowchart showing a process carried out in a calculation system in accordance with Embodiment 1. FIG. 2 is a block diagram illustrating a configuration of a main part of the calculation system in accordance with Embodiment 1. FIG. 3 is a view illustrating extraction of a contour of a first pipe by a contour extraction section. FIG. 4 is a view illustrating extraction of a contour of a second pipe by the contour extraction section. FIG. 5 is a view illustrating a first example of a bending angle calculation method in accordance with Embodiment 1. FIG. 6 is a view for describing derivation of a laying direction straight line of the first pipe by a derivation section. FIG. 7 is a view for describing derivation of a laying direction straight line of the second pipe by the derivation section. FIG. 8 is a view illustrating a second example of the bending angle calculation method in accordance with Embodiment 1. FIG. 9 is a view illustrating a third example of the bending angle calculation method in accordance with Embodiment 1. FIG. 10 is a view illustrating a fourth example of the bending angle calculation method in accordance with Embodiment 1. FIG. 11 is a view illustrating a state in which a derivation assisting tool is attached to each of the first pipe and the second pipe. FIG. 12 is a view illustrating a state in which a derivation assisting tool is attached to each of the first pipe and the second pipe. FIG. 13 is a