JP7384379B2 - Work support method for flat plate press processing, work support program for flat plate press work, and work support system for flat plate press work - Google Patents

Description

The present invention relates to a work support method, work support program, and work support system for flat plate press working that supports press work performed in the process of forming a smoothly bent curved plate from a flat plate.

The curved surface of the hull is made up of curved skins, which are smoothly bent steel plates. Curved skins are formed by bending a flat steel plate. The bending process is performed by press processing (cold working) using a press machine or linear heating using a gas flame.
Bending is a difficult task that can be called a craftsmanship, and it is not easy to secure skilled workers or pass on skills to younger workers.

Here, in Patent Document 1, even an inexperienced worker can process a steel plate having a complicated curved shape such as a ship's hull shell plate into a target shape with high accuracy. A metal plate with a curved surface is processed into a desired shape, including a curved surface, by combining angular deformation caused by applying heat and thermal contraction caused by applying heat from the front side to the back side of the metal plate. In the manufacturing method, heating wires that cause angular deformation, heating wires or heating points that cause thermal contraction are set in advance on the surface of the metal plate by geometric analysis, and these heating wires or heating points are set in advance on the surface of the metal plate. It is disclosed that heating is performed along the following directions.
Furthermore, Patent Document 2 describes a preliminary process of creating a reference curvature map by subdividing the reference surface shape and calculating the curvature for each mesh, a measurement process of obtaining three-dimensional measurement data of the machined surface shape, and a process of processing. A fitting process that creates a virtual surface shape that simulates the surface shape, a map creation process that creates a virtual curvature map by subdividing the virtual surface shape in the same way as the reference surface shape and calculating the curvature for each mesh, and a virtual curvature map. Using a surface shape evaluation method that includes a comparison process that creates a differential curvature map by comparing the map and the reference curvature map and calculating the difference, and an output process that displays the differential curvature map, the machined surface shape and the reference surface are It is disclosed that evaluation is performed by comparing the shapes.
Further, Non-Patent Document 1 discloses a bending support AR application that supports forming into a target curved surface in shipbuilding, and the use of a curvature line as a press line using a curvature line expansion method.
Additionally, Non-Patent Document 2 discloses using a laser scanner to indicate press lines on a flat plate before pressing and to perform three-dimensional measurement of a curved plate, with the aim of improving the sophistication of press work. There is.

Japanese Patent Application Publication No. 2004-74200 JP2015-227796A

Kohei Matsuo, Development of shipbuilding production support system using AR technology, 2015 (15th) Maritime Technology and Safety Research Institute research presentation, https://www.nmri.go.jp/main/publications/paper /pdf/2A/15/00/PNM2A150012-00.pdf Kazuo Hiekata, Technology development related to digitalization and data utilization of shipbuilding design and manufacturing, http://classnk-rd.com/assets/pdf/katsudou201711_D.pdf

Pressing is performed on a flat plate to form it into a target shape. Due to variations in the material properties of the flat plate and the processing precision of the operator, there is a very low possibility that the plate will bend as originally expected. It is difficult to obtain the target shape. Therefore, it is necessary to perform additional press processing on the curved plate obtained by press processing.
Patent Document 1 aims to improve the quality of processing work by heating using a gas burner, etc., and only describes the primary bending press in the previous stage, but does not improve the quality by performing additional press processing. There is no mention of improvement.
Moreover, although Patent Document 2 compares and evaluates the processed surface shape and the reference surface shape, it does not indicate a processing procedure for additional press processing for forming into the reference surface shape.
In addition, although Non-Patent Document 1 and Non-Patent Document 2 show initial press lines for a flat plate before pressing, additional press processing is performed on a curved plate after initial press processing has been performed. It does not indicate additional press lines.
Therefore, the present invention provides a flat plate press work support method, a flat plate press work support program, and a flat plate press work support system that can accurately perform additional press work and improve the accuracy of flat plate press work. The purpose is to

A work support method for press working of a flat plate according to claim 1 is a work support method for press working a flat plate to obtain a target shape, and the work support method utilizes a press line attached to a flat plate with a curved surface developed. a primary processing step of performing press working according to the primary processing procedure; a shape measurement step of measuring the shape of at least the primary processed curved plate of the flat plate obtained in the primary processing step; and at least the measured shape of the primary processed curved plate and the target shape. a determination step for comparing the degree of agreement and determining the degree of coincidence; a step for deriving an additional machining procedure using an additional machining press line to be applied to the primary processed curved plate if the degree of concordance does not satisfy a predetermined value; It is equipped with an additional processing step in which additional press processing is performed to reflect the results on the primary processed curved plate, and an additional processing confirmation step in which the shape measurement step and judgment step are repeated for the shape of the additionally processed curved plate that has undergone additional press processing . The method is characterized in that the additional processing press line is processed to give a maximum principal curvature line that traces the maximum principal direction of the principal curvatures, and a curved surface whose degree of coincidence with the target shape satisfies a predetermined value is obtained.
According to the present invention as set forth in claim 1, it is possible to perform additional press processing accurately and improve the accuracy (degree of coincidence with the target shape) of flat plate press processing. Additionally, by performing additional press work to provide a maximum principal curvature line that traces the maximum principal direction of the principal curvatures to the additional press line, additional press work can be performed efficiently.

The present invention according to claim 2 is characterized in that the degree of coincidence in the determination step is obtained by superimposing CAD data of the target shape on point group data of the measured shape of the primarily processed curved plate.
According to the second aspect of the present invention, the curved surface of the primarily processed curved plate and the curved surface of the target shape are accurately correlated, and the degree of coincidence between the shape of the primarily processed curved plate and the target shape is accurately determined. be able to.

The present invention according to claim 3 is characterized in that the superimposition is performed by extracting point group data related to the target shape from point group data of the shape of the primary processed curved plate.
According to the third aspect of the present invention, the curved surface of the primarily processed curved plate and the curved surface of the target shape can be overlapped with high accuracy.

The present invention according to claim 4 is characterized in that the degree of coincidence is determined from the difference between the normal curvature of the curvature line of the target shape and the normal curvature of the equivalent curvature line of the measured shape of the primary processed curved plate.
According to the fourth aspect of the present invention, it is possible to accurately determine the degree of coincidence between the shape of the primarily processed curved plate and the target shape, and to determine the level of additional processing.

In the present invention according to claim 5, the additional processing press line is drawn by obtaining a curve corresponding to a curvature line from the measurement result of the shape of the primary processing curved plate, calculating an angle along the curve, and obtaining a press point. It is characterized by
According to the present invention as set forth in claim 5, additional processing press lines can be accurately calculated and drawn.

The present invention according to claim 6 is characterized in that the additional processing procedure includes a press position, a press angle, and a press load of press processing.
According to the present invention as set forth in claim 6, additional processing procedures can be accurately instructed to the operator .

The present invention according to claim 7 is characterized in that the primary processing procedure and/or the additional processing procedure provide related information including the attachment position of the reinforcing material.
According to the present invention as set forth in claim 7 , it is also possible to instruct the operator regarding the attachment position of the reinforcing material.

An eighth aspect of the present invention is characterized in that the shape is measured using a laser scanner.
According to the eighth aspect of the present invention, the three-dimensional shape of the curved plate can be measured with high accuracy.

The present invention as set forth in claim 9 is characterized in that the shape and/or target shape of the primarily processed curved plate is displayed on the display means using augmented reality technology.
According to the present invention as set forth in claim 9 , it becomes easier for the operator to recognize the bending situation of the curved plate during and after press working, the working procedure, etc.

A work support program for press working of a flat plate according to claim 10 is a work support program for press working a flat plate to obtain a target shape, and the work support program is a work support program for press working a flat plate to obtain a target shape, and the work support program is a work support program for press working a flat plate to obtain a target shape. a shape acquisition step of obtaining a measurement result of measuring the shape of a primary processed curved plate of a flat plate that has been press-formed according to a primary processing procedure using a method; a target shape obtaining step of obtaining a target shape; A determination step of comparing the shape of the plate and the target shape to determine the degree of coincidence, and a step of deriving an additional machining procedure using the additional machining press line attached to the primary processed curved plate if the degree of concordance does not satisfy a predetermined value. step, and a procedure reflection step for reflecting the derivation results of the additional processing procedure on the primary processing curved plate in order to perform processing that gives the additional processing press line the maximum principal curvature line that traces the maximum principal direction of the principal curvatures as an additional press processing. The method is characterized in that a curved surface whose degree of coincidence with a target shape satisfies a predetermined value is obtained.
According to the present invention as set forth in claim 10 , it is possible to accurately perform the additional press work and improve the accuracy (degree of coincidence with the target shape) of the flat plate press work. In addition, by reflecting the derivation results of the additional processing procedure on the primary processing curved plate in order to perform processing that gives the additional processing press line the maximum principal curvature line that traces the maximum principal direction of the principal curvature as an additional press processing, Pressing can be performed efficiently.

An eleventh aspect of the present invention is characterized in that the degree of coincidence in the determination step is obtained by superimposing CAD data of the target shape on point cloud data of the measured shape of the primarily processed curved plate.
According to the present invention as set forth in claim 11 , the curved surface of the primarily processed curved plate and the curved surface of the target shape are accurately correlated, and the degree of coincidence between the shape of the primarily processed curved plate and the target shape is accurately determined. be able to.

The present invention according to claim 12 is characterized in that the superimposition is performed by extracting point group data related to the target shape from point group data of the shape of the primary processed curved plate.
According to the present invention as set forth in claim 12 , the curved surface of the primarily processed curved plate and the curved surface of the target shape can be overlapped with high precision.

The present invention according to claim 13 is characterized in that the degree of coincidence is determined from the difference between the normal curvature of the curvature line of the target shape and the normal curvature of the equivalent curvature line of the measured shape of the primary processed curved plate.
According to the thirteenth aspect of the present invention, it is possible to accurately determine the degree of coincidence between the shape of the primarily processed curved plate and the target shape, and to determine the level of additional processing.

In the fourteenth aspect of the present invention, the additional processing press line is drawn by obtaining a curve corresponding to a curvature line from the measurement result of the shape of the primary processing curved plate, calculating an angle along the curve, and obtaining a press point. It is characterized by
According to the fourteenth aspect of the present invention, additional processing press lines can be accurately calculated and drawn.

The present invention according to claim 15 is characterized in that the additional processing procedure includes a press position, a press angle, and a press load of press processing.
According to the present invention as set forth in claim 15 , additional processing procedures can be accurately instructed to the operator .

The present invention according to claim 16 is characterized in that the primary processing procedure and/or the additional processing procedure provide related information including the attachment position of the reinforcing material.
According to the present invention as set forth in claim 16 , it is also possible to instruct the operator regarding the attachment position of the reinforcing material.

A work support system for flat plate press working according to claim 17 is a work support system for press working a flat plate to obtain a target shape, and utilizes a press line attached to a flat plate with at least a curved surface developed. a press working means that performs press working according to the primary processing procedure, a shape measuring means that measures the shape of at least the primary processed curved plate of the flat plate obtained in the primary processing procedure, and at least the shape and target of the measured primary processed curved plate. comprising a determining means for comparing shapes and determining the degree of coincidence, and a procedure deriving means for deriving an additional machining procedure using an additional machining press line applied to the primary processed curved plate when the degree of concordance does not satisfy a predetermined value, The press processing means performs additional press processing to give a maximum principal curvature line that traces the maximum principal direction of the principal curvatures to the additional press line, and obtains a curved surface whose degree of coincidence with the target shape satisfies a predetermined value. Features.
According to the seventeenth aspect of the present invention, it is possible to perform additional press processing accurately and improve the accuracy (degree of coincidence with the target shape) of flat plate press processing. Additionally, by performing additional press work to provide a maximum principal curvature line that traces the maximum principal direction of the principal curvatures to the additional press line, additional press work can be performed efficiently.

The present invention as set forth in claim 18 is characterized in that the determining means and the procedure deriving means are constructed using a computer.
According to the present invention as set forth in claim 18 , it is possible to accurately and quickly determine the degree of coincidence and derive the additional processing procedure.

The present invention according to claim 19 is characterized in that a laser scanner is used as the shape measuring means.
According to the present invention as set forth in claim 19 , the three-dimensional shape of the curved plate can be measured with high accuracy.

The present invention as set forth in claim 20 is characterized in that the shape and/or target shape of the primarily processed curved plate is displayed on the display means using augmented reality technology.
According to the present invention as set forth in claim 20 , it becomes easier for the operator to recognize the bending situation during and after press working, the working procedure, etc.

According to the work support method for flat plate press working of the present invention, it is possible to accurately perform additional press work and improve the accuracy (degree of agreement with the target shape) of flat plate press work. Additionally, by performing additional press work to provide a maximum principal curvature line that traces the maximum principal direction of the principal curvatures to the additional press line, additional press work can be performed efficiently.

In addition, when determining the degree of coincidence in the determination step by superimposing the CAD data of the target shape on the measured point cloud data of the shape of the primarily processed curved plate, the degree of coincidence between the curved surface of the primarily processed curved plate and the curved surface of the target shape is determined. Correlation can be performed accurately, and the degree of coincidence between the shape of the primarily processed curved plate and the target shape can be determined with high accuracy.

In addition, when superimposition is performed by extracting point cloud data related to the target shape from point cloud data of the shape of the primary processed curved plate, the curved surface of the primary processed curved plate and the curved surface of the target shape are accurately superimposed. can be done.

In addition, when the degree of matching is calculated from the difference between the normal curvature of the curvature line of the target shape and the normal curvature of the equivalent curvature line of the measured shape of the primary processed curved plate, the degree of matching is determined by the difference between the shape of the primary processed curved plate and the target shape. The level of additional processing can be determined by accurately determining the degree of agreement with the

In addition, if the additional processing press line is drawn by finding a curve corresponding to the curvature line from the measurement results of the shape of the primary processing curved plate, calculating the angle along the curve and finding the press point, additional processing is required. Processing press lines can be accurately calculated and drawn.

Furthermore, when the additional processing procedure includes the press position, press angle, and press load of the press processing, the additional processing procedure can be accurately instructed to the operator .

Furthermore , if the primary processing procedure and/or the additional processing procedure provides related information including the reinforcing material mounting location, the operator can also be instructed about the reinforcing material mounting location.

Further, when the shape is measured using a laser scanner, the three-dimensional shape of the curved plate can be measured with high accuracy.

In addition, when displaying the shape and/or target shape of the primary processed curved plate on a display means using augmented reality technology, the operator can check the bending status of the curved plate during press processing and after processing, the processing procedure, etc. It becomes easier to recognize.

Further, according to the work support program for flat plate press working of the present invention, it is possible to accurately perform additional press working and improve the accuracy (degree of agreement with the target shape) of flat plate press working. In addition, by reflecting the derivation results of the additional processing procedure on the primary processing curved plate in order to perform processing that gives the additional processing press line the maximum principal curvature line that traces the maximum principal direction of the principal curvature as an additional press processing, Pressing can be performed efficiently.

In addition, when determining the degree of coincidence in the determination step by superimposing the CAD data of the target shape on the measured point cloud data of the shape of the primarily processed curved plate, the degree of coincidence between the curved surface of the primarily processed curved plate and the curved surface of the target shape is determined. Correlation can be performed accurately, and the degree of coincidence between the shape of the primarily processed curved plate and the target shape can be determined with high accuracy.

In addition, when superimposition is performed by extracting point cloud data related to the target shape from point cloud data of the shape of the primary processed curved plate, the curved surface of the primary processed curved plate and the curved surface of the target shape are accurately superimposed. can be done.

In addition, when the degree of matching is calculated from the difference between the normal curvature of the curvature line of the target shape and the normal curvature of the equivalent curvature line of the measured shape of the primary processed curved plate, the degree of matching is determined by the difference between the shape of the primary processed curved plate and the target shape. The level of additional processing can be determined by accurately determining the degree of agreement with the

In addition, if the additional processing press line is drawn by finding a curve corresponding to the curvature line from the measurement results of the shape of the primary processing curved plate, calculating the angle along the curve and finding the press point, additional processing is required. Processing press lines can be accurately calculated and drawn.

Furthermore, when the additional processing procedure includes the press position, press angle, and press load of the press processing, the additional processing procedure can be accurately instructed to the operator .

Furthermore , if the primary processing procedure and/or the additional processing procedure provides related information including the reinforcing material mounting location, the operator can also be instructed about the reinforcing material mounting location.

Further, according to the work support system for flat plate press working of the present invention, it is possible to accurately perform additional press working and improve the accuracy (degree of agreement with the target shape) of the flat plate press work. Additionally, by performing additional press work to provide a maximum principal curvature line that traces the maximum principal direction of the principal curvatures to the additional press line, additional press work can be performed efficiently.

Further, when the determining means and the procedure deriving means are configured using a computer, the degree of coincidence can be determined and the additional processing procedure can be derived accurately and quickly.

Furthermore, when a laser scanner is used as the shape measuring means, the three-dimensional shape of the curved plate can be measured with high accuracy.

In addition, when displaying the shape and/or target shape of the primary processed curved plate on a display means using augmented reality technology, it is easier for the operator to recognize the bending situation, processing procedure, etc. during and after press processing. Become.

Flow diagram of a work support method for flat plate press processing according to an embodiment of the present invention Detailed flow diagram from the same shape measurement step to the procedure derivation step Conceptual diagram of mapping and parameterization between the target shape and current shape Conceptual diagram of calculation for the additional processing press line Flow diagram of a work support program for flat plate press processing according to an embodiment of the present invention A block diagram of a work support system for flat plate press processing according to an embodiment of the present invention Diagram showing the calculated initial press line of the steel plate in the demonstration test Photo showing the steel plate before pressing with the same initial press line marked A photo showing a laser scan of the shape of a steel plate that was formed into a curved plate after initial press processing. Diagram showing point cloud data superimposed on CAD surface data of the same target shape Color map showing the difference in principal curvature between the same target shape and the current shape A diagram showing a curve on the surface of the current shape corresponding to the first curvature line of the surface of the target shape Diagram showing the same curvature Diagram showing the additional processing press line finally output by the work support system Diagram showing an additional processing press line obtained by a worker using the conventional method Photo showing a worker currently checking the shape using an AR application during a demonstration test

Hereinafter, a work support method for flat plate press working, a work support program for flat plate press work, and a work support system for flat plate press work according to embodiments of the present invention will be described.

FIG. 1 is a flowchart of a work support method for flat plate press working according to this embodiment. FIG. 2 is a detailed flowchart from the shape measurement step to the procedure derivation step.
The work support method for flat plate press working is used, for example, in forming a curved outer plate in a shipyard, to press a flat plate to obtain a curved plate having a target shape.
The curved surface of the target shape is developed according to the design, and is cut out as a flat plate from a steel plate or the like using an NC cutting machine or the like.

First, press working is performed according to a primary working procedure using an initial press line (press line) attached to a flat plate with a developed curved surface (S1: primary working step).

The initial press line applied to the flat plate is calculated on the flat plate developed from the designed 3D surface.
The initial press line is, for example, as described in the document ``Kohei Matsuo et al., Research on a shipbuilding press processing support system based on curvature line information, Proceedings of the Japan Society of Naval Architects and Ocean Engineers, Vol. 28, pp. 189-201, 2018''. , calculated using the curvature line expansion method.
A curvature line is a group of curves on a curved surface calculated based on the differential geometry of the curved surface. At any point on the curved surface, there is a maximum principal direction in which the normal curvature takes the maximum value and a minimum principal direction in which the normal curvature takes the minimum value. It is known that these directions are orthogonal to each other, and the curves that follow each direction are called "lines of curvature" or "curvature lines." Therefore, there are two lines of curvature: the maximum principal curvature line (first curvature line) that traces the maximum principal direction, and the minimum principal curvature line (second curvature line) that traces the minimum principal direction, and they are orthogonal on the curved surface. Build a web.
The initial press line is NC-marked on the flat plate along with other reference lines representing the attachment position of the reinforcement.
Note that the press work as the primary work (initial press work) may be a method that does not use a curvature line expansion method including die press.

After the primary processing step S1 is a shape measurement step S2.
The shape measurement step S2 is a step of measuring the entire curved surface shape of the pressed curved plate, and after the primary processing step S1, the primary curved plate obtained by pressing the flat plate is measured. Measure the shape of the processed curved plate.

In the shape measurement step S2, a laser scanner is used to measure the shape. The laser irradiates the surface on which the initial press line is drawn.
By using a laser scanner, the three-dimensional shape of the curved plate can be measured objectively and with higher precision than when using a bending mold (wooden frame). Further, since it is not necessary to manufacture a bending die, the number of work steps can be reduced.
The point cloud data obtained by measurement with a laser scanner also includes point cloud data (noise) other than the curved plate to be processed. Therefore, point cloud data processing such as removing point cloud data other than the curved plate to be processed is performed, and only point cloud data related to the curved plate to be processed is extracted (point cloud data processing step S2-1). Thereby, the curved surface shape of the curved plate can be determined.

After the shape measurement step S2, a determination step S3 is performed.
In the determination step S3, the curved plate whose shape was measured in the shape measurement step S2 is compared with the target shape, and it is determined whether the degree of matching is greater than or equal to a predetermined value.
Here, since the shape measured in the shape measurement step S2 is a primarily processed curved plate, the measured shape of the primarily processed curved plate is compared with the target shape, and it is determined whether the degree of coincidence is equal to or greater than a predetermined value.

In the determination step S3, CAD data of the target shape is superimposed on the point cloud data of the measured shape of the curved plate (superimposition step S3-1). As a result, the curved surface of the shape of the curved plate at that time (hereinafter sometimes referred to as the "current shape") is accurately correlated with the curved surface of the target shape, and the degree of matching between the current shape and the target shape is evaluated. It can be determined with high accuracy.
Specifically, if the curved surface of the target shape is expressed mathematically as a function f(u,v) using parameters (u,v), then each point cloud data Pc(n) measured by the laser scanner ,(n=1,N _p ), the corresponding (u,v) is determined. Next, the curved surface g(u,v) of the current shape is obtained so that the parameters (u,v) of each point are preserved as much as possible (curved surface generation step S3-2). The curved surface g(u,v) of the current shape is represented by a NURBS curved surface in this embodiment.
Here, since the curved plate whose shape was measured in the shape measurement step S2 is a primarily processed curved plate, the CAD data of the target shape is superimposed on the point group data of the measured shape of the primarily processed curved plate.

The point cloud data of the measured curved board shape and the CAD data of the target shape are superimposed by extracting point cloud data related to the target shape from the point cloud data of the curved board shape. Thereby, the curved surface of the curved plate at that time and the curved surface of the target shape can be superimposed with high precision.
Here, since the curved plate whose shape was measured in the shape measurement step S2 is a primarily processed curved plate, point cloud data related to the target shape is extracted from the point cloud data of the measured shape of the primarily processed curved plate and superimposed. do.

The degree of coincidence in determination step S3 is determined from the difference between the normal curvature of the curvature line of the target shape and the normal curvature of the equivalent curvature line of the measured shape of the curved plate. Thereby, the degree of coincidence between the current shape and the target shape can be determined with high precision, and the level of additional processing can be determined.
Here, since the curved plate whose shape was measured in the shape measurement step S2 is the primary processed curved plate, the normal curvature of the curvature line of the target shape and the normal curvature of the equivalent curvature line of the measured shape of the primary processed curved plate are The degree of matching is calculated from the difference between the two.
Note that the equivalent curvature line is a curvature line that corresponds to the curvature line of the target shape in the pressed curved plate.
As described above, the curvature lines include a maximum principal curvature line (first curvature line) that traces the maximum principal direction and a minimum principal curvature line (second curvature line) that traces the minimum principal direction. In this embodiment, since the first curvature line is used as the curvature line of the target shape, the first equivalent curvature line serves as the equivalent curvature line in the pressed curved plate.

If it is determined in the determination step S3 that the degree of coincidence satisfies the predetermined value (greater than or equal to the predetermined value), the press working is ended.
After pressing, the process moves to a step of performing linear heating if necessary.
The predetermined value of the degree of matching varies depending on whether or not there is post-processing such as linear heating, but it is based on the accuracy in the case of bending the shell plate according to the "Japan Steel Ship Construction Method Accuracy Standard" published by the Japan Society of Naval Architects and Ocean Engineers. It is preferable to set it based on the permissible limit of ±5 mm (which does not depend on the size of the outer panel).

On the other hand, if it is determined in the determination step S3 that the degree of coincidence does not satisfy the predetermined value (less than the predetermined value), an additional processing procedure using an additional processing press line attached to the curved plate is derived (S4: procedure derivation step). .
Here, since the primary processed curved plate and the target shape are compared in the determination step S3, an additional processing procedure using an additional processing press line applied to the primary processed curved plate is derived.
The additional processing procedure presents an additional processing press line that becomes an additional press position for obtaining the target shape for a curved plate whose degree of coincidence with the target shape does not satisfy a predetermined value. This function is handled together with the initial press line. Due to variations in sheet metal material properties and press operations, it is difficult to obtain the desired shape by pressing along the initial press line, so we supplement the press process by providing additional press lines. be able to.

In the additional processing procedure, an additional processing press line is output.
The normal curvature of the first equivalent curvature line on the current shape that corresponds to the first curvature line on the target shape (corresponding to the curvature given by the previous press working) is the normal curvature of the first curvature line on the target shape. (corresponding to the curvature that should be finally imparted by press working), determine the additional press position. Then, a final additional processing press line is determined so as to be parallel to the second curvature line.

The additional processing press line is calculated based on the information of the curvature line of the curved surface. That is, in the press work, based on geometrical interpretation, the principal curvature Kn along the curvature line in the target shape f(u,v) is given by pressing.

When the first curvature line CL1(n)(u,v),(n=1,N _CL ) in the target shape is prepared, it corresponds to the first curvature line CL1(n)(u,v) in the target shape f A curve g_CL1(n)(u,v) of the current shape g is obtained (corresponding curve derivation step S4-1).

The additional press process matches the normal curvature g_Kn(u,v) of the current shape g along the curve g_CL1(n)(u,v) with the principal curvature Kn(u,v) of the target shape f.
Specifically, as shown in equation (1) below, the second curvature line perpendicular to the first curvature line CL1(n) is selected as the reference line, and the press angle difference θ(s) is calculated from the intersection _P0 . It is determined by integrating the curvature difference between the principal curvature Kn(u,v) and the normal curvature g_Kn(u,v) along the curve.

A point where the press angle difference θ(s) exceeds a preset press angle ΔP is a press point (press point derivation step S4-2).
This is performed for all first curvature lines CL1(n), (n=1,N _CL ), and the press points of adjacent first curvature lines CL1(n) obtain additional processing press lines. Therefore, it is drawn connected to the second curvature line so as to be parallel to it (additional processing press line drawing step S4-3).
FIG. 3 is a conceptual diagram of mapping and parameterization between a target shape and a current shape. FIG. 4 is a conceptual diagram of the calculation of the additional processing press line.

In this way, the additional processing press line is drawn by determining a curve corresponding to the curvature line from the measurement result of the shape of the curved plate, calculating the angle along the curve, and determining the press point. Thereby, additional processing press lines can be accurately calculated and drawn.

Further, the additional press work can be performed efficiently by applying a principal curvature to the additional press line.

The additional processing steps include the press position, press angle, and press load of the press process. Thereby, additional processing steps can be accurately instructed to the operator.
The press position and press angle are given by the additional processing press line. Further, the press load is given by calculating how much load should be applied to the current shape in order to give a predetermined bending angle, based on the difference in the degree of coincidence between the current shape and the target shape.

The primary processing step and/or the additional processing step also provides relevant information including the location of attachment of the reinforcement. Thereby, it is possible to instruct the operator about the installation position of the reinforcing material.

Additional processing procedures such as those on the press line are transferred to a tablet PC installed at the site, and superimposed on the actual curved board using AR technology (augmented reality technology). This makes it easier for the operator to intuitively understand which position on the actual curved plate the additional processing press line corresponds to.

Furthermore, at least one of the shape of the primarily processed curved plate and the target shape may be displayed on the display means 50 using augmented reality technology. This makes it easier for the operator to recognize the bending situation of the curved plate during and after pressing, the processing procedure, etc.

After the procedure derivation step S4 is an additional processing step S5.
In the additional processing step S5, the additional processing procedure derived in the procedure derivation step S4 is reflected on the curved plate, and additional press processing is performed.
Here, since the additional processing procedure for the primary processing curved plate is derived in the procedure derivation step S4, additional press working is performed by reflecting the derived additional processing procedure on the primary processing curved board.

After the additional processing step S5 is an additional processing confirmation step S6.
In the additional processing confirmation step S6, the process returns to the shape measurement step S2, and the shape of the additionally processed curved plate, which is the curved plate subjected to the additional press processing in the additional processing step S5, is measured.
The process then proceeds to determination step S3, where the measured shape of the additionally processed curved plate is compared with the target shape, and it is determined whether the degree of coincidence is greater than or equal to a predetermined value.

If it is determined in the determination step S3 that the degree of coincidence does not satisfy the predetermined value (less than the predetermined value), the process proceeds to the additional processing step S5 via the procedure derivation step S4.
Thereafter, in determination step S3, the process is continued until it is determined that the degree of coincidence between the current shape and the target shape satisfies a predetermined value (greater than or equal to the predetermined value), that is, until a curved surface whose degree of coincidence with the target shape satisfies the predetermined value is obtained. , repeat similar steps.
In this way, after pressing a flat plate to obtain a primary curved plate, when repeating additional pressing, we derived a rational additional processing procedure according to the shape of the curved plate at any point in time (current shape). By doing so, it is possible to perform the additional press work accurately and improve the accuracy (degree of agreement with the target shape) of the flat plate press work. Thereby, for example, the time required for subsequent linear heating can be shortened. Furthermore, it is possible to build a work system that does not depend on the skill level of workers, contributing to improved productivity.

FIG. 5 is a flowchart of a work support program for flat plate press working according to this embodiment.
The work support program for flat plate press working has the same functions as the work support method for flat press working explained above. ) can be improved.

The work support program for flat plate press processing causes the computer to execute a shape acquisition step S11, a target shape acquisition step S12, a determination step S13, a procedure derivation step S14, and a procedure reflection step S15, and determines the degree of coincidence with the target shape. Obtain a curved surface that satisfies a predetermined value.
In the shape acquisition step S11, a measurement result is obtained by measuring the shape of a primarily processed curved plate of a flat plate that has been press-worked according to the primary processing procedure using press lines attached to a flat plate with a developed curved surface.
In the target shape acquisition step S12, a target shape that is the final target shape in press working is acquired.
In determination step S13, at least the measured shape of the primarily processed curved plate and the target shape are compared to determine the degree of coincidence.
If it is determined in the determination step S13 that the degree of coincidence does not satisfy the predetermined value (less than the predetermined value), an additional processing procedure using the additional processing press line attached to the primary processing curved plate is derived in a procedure derivation step S14.
In the procedure reflection step S15, the derivation result of the additional processing procedure in the procedure derivation step S14 is reflected on the primary processing curved plate.
Note that if it is determined in the determination step S13 that the degree of coincidence satisfies the predetermined position (greater than or equal to the predetermined value), the press working is ended. After pressing, the process moves to linear heating if necessary.

The operator performs additional press working on the primary processing curved board based on the additional processing procedure reflected on the primary processing curved board in the procedure reflection step S15.
After the additional press work, the operator measures the shape of the additionally processed curved plate that has been subjected to the additional press work, and inputs the measurement results into the computer.
When the measurement result of the shape of the additionally processed curved plate is input into the computer, the work support program for flat plate press processing moves to judgment step S13, and compares the measured shape of the additionally processed curved plate with the target shape, and determines whether they match. Determine the degree.
If it is determined in the determination step S13 that the degree of coincidence does not satisfy the predetermined value (less than the predetermined value), the process proceeds to the additional processing step S15 via the procedure derivation step S14.
Thereafter, similar steps are repeated until it is determined in determination step S13 that the degree of coincidence between the shape of the pressed curved plate and the target shape satisfies a predetermined value (greater than or equal to the predetermined value).
Thereby, the additional press work can be performed accurately and the accuracy of the flat plate press work (degree of coincidence with the target shape) can be improved.

The degree of coincidence in the determination step S13 is preferably determined by superimposing CAD data of the target shape on the measured point group data of the shape of the primarily processed curved plate. Thereby, the curved surface of the primarily processed curved plate and the curved surface of the target shape can be accurately correlated, and the degree of coincidence between the shape of the primarily processed curved plate and the target shape can be accurately determined.

Further, it is preferable that the superimposition is performed by extracting point group data related to the target shape from the point group data of the shape of the primary processed curved plate. Thereby, the curved surface of the primary processed curved plate and the curved surface of the target shape can be overlapped with high precision.

Further, it is preferable that the degree of coincidence is determined from the difference between the normal curvature of the curvature line of the target shape and the normal curvature of the equivalent curvature line of the measured shape of the primary processed curved plate. Thereby, it is possible to accurately determine the degree of coincidence between the shape of the primarily processed curved plate and the target shape, and to determine the level of additional processing.

Further, it is preferable that the additional processing press line is drawn by obtaining a curve corresponding to a curvature line from the measurement result of the shape of the primary processing curved plate, calculating an angle along the curve, and obtaining a press point. Thereby, additional processing press lines can be accurately calculated and drawn.

Moreover, it is preferable that the additional processing procedure includes the press position, press angle, and press load of press processing. Thereby, additional processing steps can be accurately instructed to the operator.

Moreover, it is preferable that the additional press work is a process that imparts a principal curvature to the additional press line. Thereby, additional press working can be performed efficiently.

It is also preferred that the primary processing procedure and/or the additional processing procedure provide relevant information including the attachment location of the reinforcement. Thereby, it is possible to instruct the operator about the installation position of the reinforcing material.

FIG. 6 is a block diagram of a work support system for flat plate press working according to this embodiment. The flat plate press work support system has the same functions as the flat plate press work support method and the flat plate press work support program explained above, and performs additional press processing accurately and improves the flat plate press work. Accuracy (degree of matching with target shape) can be improved.

The flat plate press working support system includes a press working means 10, a shape measuring means 20, a determining means 30, and a procedure deriving means 40, and obtains a curved surface whose degree of coincidence with a target shape satisfies a predetermined value.
The press working means 10 performs press working according to a primary working procedure using press lines attached to a flat plate having at least a curved surface.
The shape measuring means 20 measures at least the shape of the primary processed curved plate of the flat plate obtained in the primary processing procedure.
The determining means 30 compares at least the measured shape of the primarily processed curved plate with the target shape and determines the degree of coincidence.
The procedure deriving means 40 derives an additional processing procedure using an additional processing press line applied to the primary processed curved plate when the determining means 30 determines that the degree of coincidence does not satisfy a predetermined value (less than a predetermined value).
Note that if the determining means 30 determines that the degree of coincidence satisfies the predetermined position (or higher than the predetermined position), the press working is terminated. After pressing, the process moves to linear heating if necessary.

The work support system for flat plate press working uses the press working means 10 to perform additional press working on the primary processed curved plate based on the additional working procedure derived by the procedure deriving means 40.
After the additional press working, the shape measuring means 20 measures the shape of the additionally processed curved plate that has been subjected to the additional press working.
The determining means 30 compares the measured shape of the additionally processed curved plate with the target shape, and determines whether the degree of coincidence is greater than or equal to a predetermined value.
If the determining means 30 determines that the degree of coincidence does not satisfy the predetermined value (less than the predetermined value), the procedure deriving means 40 derives an additional processing procedure, and the press processing means 10 performs additional press processing again. Let's do it.
Thereafter, the same procedure is repeated until the determining means 30 determines that the degree of coincidence between the shape of the pressed curved plate and the target shape satisfies a predetermined value (greater than or equal to the predetermined value).
Thereby, the additional press work can be performed accurately and the accuracy of the flat plate press work (degree of coincidence with the target shape) can be improved.

Note that it is preferable that the determining means 30 and the procedure deriving means 40 be configured using a computer. Thereby, it is possible to accurately and quickly determine the degree of coincidence and derive the additional processing procedure.

Further, it is preferable to use a laser scanner as the shape measuring means 20. Thereby, the three-dimensional shape of the curved plate can be measured with high accuracy.

Further, it is preferable to display the shape of the primarily processed curved plate and/or the target shape on the display means 50 using augmented reality technology. This makes it easier for the operator to recognize the bending situation of the curved plate during and after pressing, the processing procedure, etc. The display means 50 is a tablet PC or the like.

Next, the results of a demonstration experiment of the work support system for flat plate press working according to the present invention will be explained.
In order to evaluate the flat plate press working support system according to the present invention, a press working demonstration experiment was conducted at a shipyard using a steel plate for an actual ship. In the demonstration experiment, workers carried out stamping according to the stamping procedures output by the work support system. The main specifications of the steel plate used in the demonstration experiment are shown in Table 1 below.

FIG. 7 is a diagram showing the calculated initial press line of the steel plate.
These initial press lines were calculated to have a press length of 3 m and a press angle of 0.4 degrees (equivalent to a press load of 160 tons), taking into account the characteristics of the shipyard press machine.
FIG. 8 is a photograph showing a steel plate before pressing with initial press lines marked. The initial press line was marked on the steel plate by an NC machine. The operator performed the first press work according to the initial press line and the press load marked on the steel plate.

After the initial press working was completed, the shape of the curved steel plate was measured using a laser scanner. FIG. 9 is a photograph showing laser scanning of the shape of a steel plate that has undergone initial press processing and has become a curved plate.
By laser scanning, 585,362 (N _p in paragraph 0059) points were extracted as point group data on the steel plate.

FIG. 10 shows point cloud data of 585,362 points superimposed on the CAD surface data of the target shape. As shown in the partially enlarged view at the top right of the figure, the point cloud data and the points on the CAD surface are associated on a one-to-one basis. As a result, parameters (u,v) representing the CAD surface are assigned to each point cloud data acquired by the laser scanner.

FIG. 11 is a color map showing the difference between the principal curvature of the target shape and the normal curvature of the equivalent curvature line of the current shape. The difference in curvature means the amount of additional stamping required.

FIG. 12 is a diagram showing a curve on the surface of the current shape that corresponds to the first curvature line of the surface of the target shape. This corresponds to the curve g_CL1(n)(u,v) mentioned above.
FIG. 13 is a diagram showing the curvature, and FIG. 13(a) shows the principal curvature along the first curvature line CL1(n)(u,v) on the target shape, and FIG. 13(b) shows the principal curvature on the current shape. The normal curvature along the first equivalent curvature line g_CL1(n)(u,v) is shown. By integrating the difference in curvature between these curves, the press angle of the additional processing press line is obtained.

FIG. 14 is a diagram showing the additional processing press line finally output by the work support system. In the circled area in the figure, bending is insufficient, and the additional press line at this position indicates that additional pressing is required. In this demonstration experiment, the initial press work was slightly excessively bent, so an additional press line was output mainly to correct the bend.
FIG. 15 is a diagram showing an additional processing press line obtained by an operator using a conventional method (shape confirmation using a wooden mold). Comparing Figures 14 and 15, it can be seen that the additional processing press lines output by the work support system tend to be the same as the additional processing press lines obtained by the operator using the conventional method, which indicates the effectiveness of the work support system. confirmed.

FIG. 16 is a photograph showing a state in which a worker is currently checking the shape using an AR application. In this demonstration experiment, information was superimposed using AR (augmented reality technology) using a tablet PC as the display means 50. AR allows for effective information representation and communication.

The present invention can be widely used in shipyards and other sites where flat plates are bent using presses, and is useful for improving productivity in bending, improving quality, stabilizing the production system, and reducing processing costs. This contributes to reducing the number of employees and making it easier to pass on skills.

10 Press processing means 20 Shape measurement means 30 Judgment means 40 Procedure derivation means 50 Display means S1 Primary processing step S2 Shape measurement step S3 Judgment step S4 Procedure derivation step S5 Additional processing step S6 Additional processing confirmation step S11 Shape acquisition step S12 Target shape acquisition Step S13 Judgment step S14 Procedure derivation step S15 Procedure reflection step

Claims (20)

A work support method for press working a flat plate to obtain a target shape, the method comprising:
a primary processing step of performing the pressing according to a primary processing procedure using a press line attached to the flat plate with a developed curved surface;
a shape measuring step of measuring the shape of the primary processed curved plate of the flat plate obtained at least in the primary processing step;
a determination step of comparing at least the measured shape of the primarily processed curved plate and the target shape to determine the degree of coincidence;
a procedure derivation step of deriving an additional processing procedure using an additional processing press line applied to the primary processing curved plate when the degree of coincidence does not satisfy a predetermined value;
an additional processing step of reflecting the additional processing procedure on the primary processing curved plate and performing additional press processing;
an additional processing confirmation step of repeating the shape measurement step and the determination step for the shape of the additional processing curved plate subjected to the additional press processing,
As the additional press work, a process is performed to give a maximum principal curvature line that traces the maximum principal direction of the principal curvatures to the additional press line to obtain the curved surface whose degree of coincidence with the target shape satisfies the predetermined value. A work support method for flat plate press processing characterized by the following. The flat plate press according to claim 1, wherein the degree of coincidence in the determining step is obtained by superimposing CAD data of the target shape on point cloud data of the measured shape of the primarily processed curved plate. Processing work support method. 3. The work support for flat plate press working according to claim 2, wherein the superimposition is performed by extracting the point cloud data related to the target shape from the point cloud data of the shape of the primary processed curved plate. Method. 2. The degree of coincidence is determined from the difference between the normal curvature of the curvature line of the target shape and the normal curvature of the measured equivalent curvature line of the shape of the primary processed curved plate. The work support method for flat plate press working according to claim 3. The additional processing press line is characterized in that a curve corresponding to a curvature line is determined from the measurement results of the shape of the primary processing curved plate, an angle along the curve is calculated, and press points are determined and drawn. The work support method for flat plate press working according to any one of claims 1 to 4. The work support method for flat plate press working according to any one of claims 1 to 5, wherein the additional working procedure includes a press position, a press angle, and a press load of the press work. Work support for flat plate press working according to any one of claims 1 to 6 , wherein the primary processing procedure and/or the additional processing procedure provides related information including the attachment position of the reinforcing material. Method. 8. The work support method for flat plate press working according to claim 1 , wherein the measurement of the shape is performed using a laser scanner. The flat plate press processing according to any one of claims 1 to 8 , characterized in that the shape and/or the target shape of the primary processed curved plate are displayed on a display means using augmented reality technology. work support methods. A work support program for press working a flat plate to obtain a target shape,
to the computer,
a shape acquisition step of acquiring a measurement result of measuring the shape of the first-processed curved plate of the flat plate that has been press-worked according to a primary-processing procedure using a press line attached to the flat plate with a developed curved surface;
a target shape obtaining step for obtaining the target shape;
a determination step of comparing at least the measured shape of the primarily processed curved plate and the target shape to determine the degree of coincidence;
a procedure derivation step of deriving an additional processing procedure using an additional processing press line attached to the primary processing curved plate when the degree of coincidence does not satisfy a predetermined value;
A procedure reflection step of reflecting the derivation result of the additional processing procedure on the primary processing curved plate in order to perform processing that gives the additional processing press line a maximum principal curvature line that traces the maximum principal direction of the principal curvatures as an additional press processing. and execute
A work support program for flat plate press processing, characterized in that the curved surface is obtained such that the degree of coincidence with the target shape satisfies the predetermined value. 11. The flat plate press according to claim 10 , wherein the degree of coincidence in the determining step is obtained by superimposing CAD data of the target shape on point cloud data of the measured shape of the primarily processed curved plate. Processing work support program. The work support for flat plate press working according to claim 11 , wherein the superimposition is performed by extracting the point cloud data related to the target shape from the point cloud data of the shape of the primary processed curved plate. program. 12. The degree of coincidence is determined from the difference between the normal curvature of the curvature line of the target shape and the normal curvature of the measured equivalent curvature line of the shape of the primary processed curved plate. The work support program for flat plate press processing according to claim 12 . The additional processing press line is characterized in that a curve corresponding to a curvature line is determined from the measurement results of the shape of the primary processing curved plate, an angle along the curve is calculated, and press points are determined and drawn. The work support program for flat plate press working according to any one of claims 10 to 13 . The work support program for flat plate press working according to any one of claims 10 to 14 , wherein the additional working procedure includes a press position, a press angle, and a press load of the press work. Work support for flat plate press working according to any one of claims 10 to 15 , wherein the primary processing procedure and/or the additional processing procedure provides related information including the attachment position of the reinforcing material. program. A work support system for press forming a flat plate to obtain a target shape,
Pressing means that performs the pressing according to a primary processing procedure using a press line attached to the flat plate with at least a developed curved surface;
Shape measuring means for measuring the shape of the primary processed curved plate of the flat plate obtained at least in the primary processing procedure;
determining means for comparing at least the measured shape of the primarily processed curved plate and the target shape to determine the degree of coincidence;
A procedure deriving means for deriving an additional processing procedure using an additional processing press line attached to the primary processing curved plate when the degree of coincidence does not satisfy a predetermined value,
The press working means performs additional press work to give a maximum principal curvature line that traces the maximum principal direction of the principal curvatures to the additional press line, and the degree of coincidence with the target shape satisfies the predetermined value. A work support system for flat plate press processing, characterized in that the curved surface is obtained. 18. The work support system for flat plate press working according to claim 17 , wherein the determining means and the procedure deriving means are configured using a computer. 19. The work support system for flat plate press working according to claim 17 or 18 , wherein a laser scanner is used as the shape measuring means. The flat plate press processing according to any one of claims 17 to 19 , characterized in that the shape and/or the target shape of the primary processed curved plate are displayed on a display means using augmented reality technology. work support system.