JP2008242516A - Three-dimensional model construction method for woven fabric and three-dimensional model construction device for woven fabric - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a three-dimensional model construction method for woven fabric and a three-dimensional model construction device for the woven fabric, for simulating deformation of the woven fabric when processing the woven fabric into a product shape. <P>SOLUTION: All the possible deformation conditions are applied to a given woven fabric standard in advance to create a database of two-axis deformation behavior, a target curved surface is converted into a Bezier curved surface from read CAD data of the product shape, and devided according to a division rule of the Bezier curved surface in each size of a woven fabric texture one cycle, a curvature in an area center point and a path length of a boundary line of each area is calculated to a minute area, a three-dimensional model is created by use of forward calculation technique, and a deformation state of each the minute portion is calculated. A result is integrated to obtain a distortion amount distribution of the whole curved surface. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for constructing a three-dimensional model of a woven fabric and an apparatus for constructing a three-dimensional model of the woven fabric, and more specifically, when the fabric is stretched in the warp direction and the weft direction simultaneously, It is possible to simulate how the fabric deforms when bent in the warp and weft directions at the same time, and it is possible to simulate how the fabric deforms when processed into a product shape The present invention relates to a three-dimensional model construction method and a three-dimensional model construction apparatus for textiles.

The inventors of the present invention provide a method for modeling a fabric structure and a fabric for predicting the fabric limit density and predicting the possibility of weaving based on the determination of the fabric critical density without requiring special knowledge such as three-dimensional computer graphics. A structural modeling device has been developed (see Patent Document 1) and a patent application has been filed.
For example, when the three-dimensional modeled fabric is deformed to a specified stretch ratio, the fabric structure is recalculated and the recalculated fabric three-dimensional model is output. Has been developed (see Patent Document 2) and has applied for a patent.

The three-dimensional modeling method and the three-dimensional modeling apparatus for the fabric structure disclosed in Patent Document 2 describe how the fabric is formed when the fabric is stretched simultaneously in two axial directions or when the fabric is bent simultaneously in two axial directions. It has not yet reached the area for simulating whether to deform. However, in recent textile design fields, for example, when designing automobile seats and interior materials, it is strongly required to predict the deformation characteristics of the textile in order to improve quality.
JP 2006-209706 A JP 2006-274521 A

  Therefore, in the present invention, when the fabric modeled by the fabric structure modeling method and the fabric structure modeling device of Patent Document 1 is stretched in two directions at the same time or bent in two directions at the same time, 3D model construction method of fabric and 3D model of fabric, which can simulate how fabric is deformed when processed into product shape Providing a construction device is a problem to be solved.

The above-mentioned problem can be solved by the fabric three-dimensional model construction method and the fabric three-dimensional model construction device described in the claims, and the fabric three-dimensional model construction method according to claim 1 The woven fabric is composed of the fabric standard data including at least one of the organization chart, the woven density of the fabric, and the thickness of the yarn, and the physical property data of the yarn including at least one of the tensile properties and the compressive properties of the yarn as input values. Performing a three-dimensional modeling of the shape of each of the yarns, outputting a three-dimensional model of the fabric as an aggregate of the yarn shapes assembled by the three-dimensional modeling, and a three-dimensional model of the fabric Recalculating the fabric structure when biaxially stretched to the specified warp direction elongation rate ε ₁ and weft direction elongation rate ε ₂ , and outputting the recalculated three-dimensional model of the fabric, It is to have.

  According to a second aspect of the present invention, the step of recalculating the fabric structure in the case of biaxial stretching calculates the yarn weaving rate in each stretching direction from the three-dimensional model of the fabric before deformation, Recalculate automatically by selecting either the first recalculation process when the stretch rate is less than or equal to the weaving rate and the second recalculation process when the stretch rate in each direction is greater than or equal to the weave rate It is to be.

  According to a third aspect of the present invention, in the first recalculation process, as the stretch rate in each direction of the fabric increases, the yarn in the stretch direction of each direction in the fabric shifts from the bent structure to the linear structure and the crimp height increases. Therefore, the three-dimensional model of the woven fabric is recalculated on the basis of the phenomenon that the yarn orthogonal to each stretching direction is pulled and contracts in the transverse direction.

  According to a fourth aspect of the present invention, in the second recalculation process, the yarn stretch rate in each direction increases with an increase in the fabric stretch rate, based on a yarn stress-strain curve measured in advance. Based on the above, the 3D model of the fabric is recalculated.

The method for constructing a three-dimensional model of a woven fabric according to claim 5 includes a woven fabric structure chart, a woven fabric standard data including at least one of the woven density of the woven fabric, and the thickness of the yarn, and one of the tensile property and the compressive property of the yarn. A step of performing three-dimensional modeling of the shape of each yarn constituting the fabric using at least physical property data of the yarn including the input, and the fabric as an aggregate in which the shape of the yarn is assembled by the three-dimensional modeling A warp direction curvature κ ₁ or warp direction curvature radius 1 / κ ₁ , and a weft direction curvature κ ₂ or a weft direction curvature radius 1. a step of recalculating the woven structure when bent up / kappa _2, and outputting the three-dimensional model of fabric the recalculated, is to have a.

Also, three-dimensional model construction method of the fabric of claim 6, for any curved surface is specified, the basic unit structure of weave structure as a unit, the warp direction s ₁ piece, total s consisting of _two weft direction s A step of dividing the region into ₁ × s ₂ regions, a step of calculating a state in which the divided regions are deformed by modeling the woven fabric structure according to claim 1 or 5, and superimposing these The step of calculating the deformation state, stress distribution, and strain amount distribution of the entire specified arbitrary curved surface shape, and outputting the calculated three-dimensional model, stress distribution, and strain amount distribution of the entire arbitrary curved surface shape of the fabric. And having a process.

The method for constructing a three-dimensional model of a woven fabric according to claim 7 includes a woven fabric structure diagram, a woven fabric standard data including at least one of a woven density of the woven fabric, and a thickness of the yarn, and any one of a tensile property and a compressive property of the yarn. Under the biaxial tensile deformation at the time of a combination of a plurality of warp direction elongation ratios ε ₁ and a plurality of weft direction elongation ratios ε ₂ at an arbitrary interval with at least the physical property data of the yarns included as input values, Of a fabric under biaxial pure bending deformation when a combination of a warp direction curvature κ ₁ or a warp direction curvature radius 1 / κ ₁ and a plurality of weft direction curvature κ ₂ or a weft direction curvature radius 1 / κ ₂ A plurality of three-dimensional models are generated, stresses and strains are calculated from these three-dimensional models, these values are stored in a database, and the basic unit structure of the woven fabric structure for any specified curved surface shape. Warp direction s ₁ piece as one unit, is divided into a total of s ₁ × s ₂ regions consisting of _two weft direction s, the state of being deformed from the database calculated for each divided region, these This is to calculate the deformation state, the stress distribution, and the strain amount distribution of the entire arbitrary curved surface shape specified by superimposing the entire region.

The apparatus for constructing a three-dimensional model of a woven fabric according to claim 8 includes a woven fabric structure chart, a woven fabric standard data including at least one of a woven fabric density and a yarn thickness, and any one of a tensile property and a compressive property of the yarn. Three-dimensional modeling means for performing three-dimensional modeling of the shape of each yarn constituting the woven fabric using at least the physical property data of the yarn including the input value, and an assembly in which the shape of the yarn is assembled by the three-dimensional modeling A three-dimensional model output means for outputting a three-dimensional model of the woven fabric as a fabric, and a woven fabric in which the three-dimensional model of the woven fabric is biaxially stretched up to the specified warp direction elongation rate ε ₁ and weft direction elongation rate ε ₂ And a recalculated three-dimensional model output means for outputting the recalculated three-dimensional model of the fabric after recalculating the structure.

The apparatus for constructing a three-dimensional model of a woven fabric according to claim 9 is provided with at least one of a woven fabric structure diagram, a woven fabric density data, a woven fabric density data, and a yarn thickness, and a tensile property and a compressive property of the yarn. Three-dimensional modeling means for performing three-dimensional modeling of the shape of each yarn constituting the woven fabric using at least the physical property data of the yarn including the input value, and an assembly in which the shape of the yarn is assembled by the three-dimensional modeling A three-dimensional model output means for outputting a three-dimensional model of the woven fabric, and a curvature κ _{1 in the} warp direction or a curvature radius 1 / κ _{1 in} the warp direction and a curvature κ _{2 in the} weft direction specifying the three-dimensional model of the woven fabric. or after recalculating the woven structure when bent to a radius of curvature 1 / kappa ₂ in the weft direction, have a, a bending deformation 3D model output means for outputting the three-dimensional model of the recalculated fabric It is to be.

Further, the three-dimensional model constructing apparatus of the fabric of claim 10, for any curved surface is specified, the basic unit structure of weave structure as a unit, the warp direction s ₁ piece, consisting of _two weft direction s total s Dividing means for dividing the area into ₁ × s ₂ areas, deformation state calculating means for calculating a state in which each divided area is deformed by modeling the fabric structure according to claim 1 or 5, and By calculating the deformation state, stress distribution, and strain distribution of the entire specified curved surface shape by superimposing, the three-dimensional model, stress distribution, and strain distribution of the entire curved surface shape of the calculated fabric are calculated. A three-dimensional model output means for outputting the entire area.

  A recording medium according to an eleventh aspect records a software program for executing the three-dimensional modeling means, the three-dimensional model output means, and the recalculated three-dimensional model output means described in the eighth aspect.

  A recording medium according to a twelfth aspect records a software program for executing the three-dimensional modeling means, the three-dimensional model output means, and the bending deformation three-dimensional model output means described in the ninth aspect.

The method for constructing a three-dimensional model of a woven fabric according to the present invention includes a woven fabric chart, a woven fabric standard data including at least one of the woven density of the woven fabric, and a thickness of the yarn, and a yarn including at least one of a tensile property and a compressive property of the yarn. The three-dimensional modeling of the shape of each yarn constituting the woven fabric using the physical property data of the three-dimensional model as an input value, and the three-dimensional woven fabric as an aggregate in which the yarn shapes are assembled by the three-dimensional modeling Outputting a model, recalculating the fabric structure when the three-dimensional model of the fabric is biaxially stretched to the specified warp direction elongation rate ε ₁ and weft direction elongation rate ε ₂ , Outputting a calculated three-dimensional model of the fabric, and simulating how the fabric deforms when the three-dimensional modeled fabric is stretched simultaneously in two directions. Can do.

  The step of recalculating the fabric structure in the case of biaxial stretching calculates the weaving rate of the yarn in each stretching direction from the three-dimensional model of the fabric before deformation, and the stretching rate in each direction is By automatically selecting and recalculating either the first recalculation process when the rate is less than the rate or the second recalculation process when the stretch rate in each direction is greater than or equal to the weaving rate, 3 When a dimensionally modeled fabric is stretched in two directions simultaneously, it can be well recalculated how the fabric deforms.

  Further, in the first recalculation process, as the stretch rate in each direction of the fabric increases, the yarn in the stretch direction in each direction in the fabric shifts from the bent structure to the linear structure and the crimp height decreases. From the case where the three-dimensional modeled fabric is stretched in two directions simultaneously by recalculating the three-dimensional model of the fabric based on the phenomenon that the yarn orthogonal to each stretching direction is pulled and contracts in the transverse direction, It can be recalculated well how the fabric is deformed.

  In addition, the second recalculation process is based on a phenomenon in which the yarn elongation rate in each direction increases with an increase in the fabric elongation rate based on a pre-measured yarn stress-strain curve. By recalculating the three-dimensional model, it is possible to satisfactorily recalculate how the fabric deforms when the three-dimensional modeled fabric is stretched simultaneously in two directions.

The method for constructing a three-dimensional model of a woven fabric according to the present invention includes at least one of a fabric structure chart, a woven fabric standard data including at least one of a woven fabric density and a yarn thickness, and at least one of a tensile property and a compressive property of a yarn. The process of performing three-dimensional modeling of the shape of each yarn constituting the fabric using the physical property data of the yarn including the input value, and the fabric as an aggregate in which the shape of the yarn is assembled by the three-dimensional modeling A step of outputting a three-dimensional model; a warp direction curvature κ ₁ or a warp direction curvature radius 1 / κ ₁ , and a weft direction curvature κ ₂ or a weft direction curvature radius 1 / κ. _And a step of outputting a three-dimensional model of the recalculated woven fabric simultaneously, thereby bending the three-dimensional modeled woven fabric in two directions simultaneously. It is possible to simulate how the fabric deforms when curled.

Further, the three-dimensional model construction method for a woven fabric according to the present invention is a total s ₁ composed of a warp direction s ₁ and a weft direction s ₂ for a specified arbitrary curved surface shape, with the basic unit structure of the fabric structure as one unit. a step of dividing into × s ₂ pieces of regions, calculating a state of being deformed by the modeling of the fabric structure according to claim 1 or 5 for each divided area, said by superimposing them A step of calculating a deformation state, a stress distribution and a strain distribution of the entire specified arbitrary curved surface shape, and a step of outputting a three-dimensional model, a stress distribution and a strain distribution of the calculated arbitrary curved surface shape of the fabric And simulating how the fabric of an arbitrary curved surface shape is deformed when a three-dimensional modeled fabric is stretched simultaneously in two directions or bent simultaneously in two directions. DOO are possible, it is possible to simulate or disfigure how when processed fabric product shape.

The method for constructing a three-dimensional model of a woven fabric according to the present invention includes at least one of a fabric structure chart, a woven fabric standard data including at least one of a woven fabric density and a yarn thickness, and at least one of a tensile property and a compressive property of a yarn. Biaxial tensile deformation at a combination of a plurality of warp direction elongation ratios ε ₁ and a plurality of weft direction elongation ratios ε ₂ at an arbitrary interval and a plurality of warp threads 3 of the fabric under biaxial pure bending deformation in the combination of the curvature κ _{1 in the} direction or the curvature radius 1 / κ ₁ in the warp direction and the curvature κ _{2 in the} plurality of weft directions or the curvature radius 1 / κ _{2 in} the weft direction Generate multiple dimensional models, calculate stress and strain from these 3D models, store these values in the database, and create the basic unit structure of the woven fabric structure for any specified curved surface shape. Warp direction s ₁ pieces as a unit, is divided into a total of s ₁ × s ₂ regions consisting of _two weft direction s, the state of being deformed from the database calculated for each region obtained by dividing, these total When a three-dimensional modeled fabric is stretched in two directions at the same time or bent in two directions at the same time by calculating the deformation state, stress distribution, and strain distribution of the entire curved surface specified by overlapping the regions. In this case, it is possible to simulate how the fabric is deformed, and it is possible to simulate the deformation state, stress distribution, and strain distribution of the entire curved surface shape when the fabric is processed into a product shape. .

Further, the three-dimensional model construction apparatus for a woven fabric according to the present invention includes at least one of a woven fabric structure chart, a woven fabric density data, a woven fabric density data, and a yarn thickness, and at least one of a tensile property and a compressive property of the yarn. Three-dimensional modeling means for performing three-dimensional modeling of the shape of each yarn constituting the woven fabric using the physical property data of the yarn including the input value, and an aggregate in which the shape of the yarn is assembled by the three-dimensional modeling A three-dimensional model output means for outputting a three-dimensional model of the woven fabric, and a woven fabric structure in which the three-dimensional model of the woven fabric is biaxially stretched to the specified warp direction elongation rate ε ₁ and weft direction elongation rate ε ₂ And recalculating the three-dimensional model output means for outputting the recalculated three-dimensional model of the fabric, thereby simultaneously stretching the three-dimensional modeled fabric in two directions. If so, it can be simulated how the fabric is deformed.

Further, the three-dimensional model construction apparatus for a woven fabric according to the present invention includes at least one of a woven fabric structure chart, a woven fabric density data, a woven fabric density data, and a yarn thickness, and at least one of a tensile property and a compressive property of the yarn. Three-dimensional modeling means for performing three-dimensional modeling of the shape of each yarn constituting the woven fabric using the physical property data of the yarn including the input value, and an aggregate in which the shape of the yarn is assembled by the three-dimensional modeling A three-dimensional model output means for outputting a three-dimensional model of the fabric, a warp direction curvature κ ₁ or a warp direction curvature radius 1 / κ ₁ , and a weft direction curvature κ _2, A bending deformation three-dimensional model output means for outputting a three-dimensional model of the re-calculated fabric after re-calculating the fabric structure when bent to a curvature radius of 1 / κ _{2 in the} weft direction. Thus, it is possible to simulate how the fabric is deformed when the three-dimensional modeled fabric is bent simultaneously in two directions.

Also, three-dimensional model constructing apparatus fabric of the present invention, for any curved surface is specified, the basic unit structure of weave structure as a unit, the warp direction s ₁ piece, total consisting of _two weft direction s s ₁ overlapping dividing means for dividing the × s ₂ pieces of regions, and a deformed state calculating means for calculating a state of being deformed by the modeling of the fabric structure according to claim 1 or 5 for each divided region, these By calculating the deformation state, stress distribution, and strain distribution of the entire specified curved surface shape by combining the three-dimensional model, stress distribution, and strain distribution of the entire curved surface shape of the calculated fabric. By having the whole area three-dimensional model output means for outputting, it is possible to simulate the deformation state, stress distribution, and strain amount distribution of the entire curved surface shape when the fabric is processed into a product shape.

  Further, according to the recording medium on which the software program for executing the three-dimensional modeling means, the three-dimensional model output means, and the recalculated three-dimensional model output means is recorded, the woven fabric assembled by the three-dimensional modeling is simultaneously expanded in two directions. In such a case, how the fabric is deformed can be simulated by a general-purpose computer or the like.

  According to the recording medium on which the software program for executing the three-dimensional modeling means, the three-dimensional model output means, and the bending deformation three-dimensional model output means is recorded, the woven fabric assembled by the three-dimensional modeling is bent in two directions simultaneously. In such a case, how the fabric is deformed can be simulated by a general-purpose computer or the like.

Next, the best mode for carrying out the present invention will be described with reference to the drawings.
First, the structure of the three-dimensional model construction apparatus for fabric according to the present invention will be described with reference to FIG.
As shown in FIG. 1, the computer 1 is a well-known computer and is provided with a CPU 50 that controls the computer 1. The CPU 50 is inserted with a ROM 51 storing a program such as a BIOS executed by the CPU 50, a RAM 52 temporarily storing data, and a CD-ROM 54 which is a data storage medium via the bus 55 to read the data. Are connected to a CD-ROM drive 53 that performs data storage and an HDD 60 that is a data storage device. The HDD 60 includes a program storage area 61 that stores various programs executed by the computer 1 including a modeling program, and a database storage area 62 that stores information such as various data input when the program is executed. Is provided.

Further, the CPU 50 includes a display control unit 30 that performs screen display processing of the monitor 31 for displaying the operation screen and the execution result of the program to the user via the bus 55, and a keyboard on which the user inputs an operation. 41 and a mouse 42, and an input detection unit 40 that detects these inputs is connected.
The computer 1 may be provided with a flexible disk drive (not shown), an input / output unit for voice, various interfaces, and the like.

The CD-ROM 54 stores software in which necessary programs are incorporated, settings and data used when executing the programs, and program storage provided from the CD-ROM 54 to the HDD 60 at the time of introduction. It is stored in the area 61 or the like.
The method for acquiring the program of the computer 1 and its usage data is not limited to the method using the CD-ROM 54, but may be another recording medium such as a flexible disk or an MO. You may acquire from other terminals above.

Next, a three-dimensional modeling process for displaying the fabric three-dimensional structure in the computer 1 having the above configuration will be described with reference to the drawings.
FIG. 2 is a flowchart showing the flow of the three-dimensional modeling process of the woven structure, and FIG. 3 is an explanatory diagram showing the state of the cross section of the yarn at the intersection point in the Peirce model.

  In general, to represent the three-dimensional shape of an object with 3D computer graphics, the first step is to divide the object into geometric basic elements such as points, lines, and polygons (polygons). A process for determining a coordinate group of the basic elements in the three-dimensional space is required. Thereafter, as a second stage, a process of converting and expressing the coordinate group of the three-dimensional space on the two-dimensional space is performed. The former process is called modeling, and the latter process is called rendering.

  In order to three-dimensionally express the shape of the warp and weft constituting the woven fabric from the woven fabric diagram, as shown in FIG. 2, a woven fabric having a woven fabric diagram 101, a yarn thickness 102, a woven density 103, a stripe 104, and the like. Based on the information about the standard 105, the coordinates in the woven fabric are determined for each warp yarn to be configured and the modeling process 106 is performed to obtain a three-dimensional shape model 107 of the woven fabric. After that, by giving the coordinate information 124 regarding the display of the viewpoint 121 for displaying the three-dimensional shape model, the rotation angle 122 of the model, the light source 123, and the like, and performing the rendering process 125, the three-dimensional shape image 130 can be expressed.

  When the modeling process 106 is performed using three-dimensional computer graphics, in addition to a polygon model that expresses a model by combining a plurality of polygons, a method that expresses a model by a spline curve, a method that expresses a model by a Bezier curve or a Bezier curved surface, or the like. There are various ways. Here, a modeling method using a cubic Bézier surface that can be expressed with relatively few parameters is adopted.

  At this time, the coordinate system representing the model structure is the right-handed coordinate system in which the lower left tissue point of the organization chart is considered as the origin of coordinates, the weft direction is the x axis, the warp direction is the y axis, and the thickness direction is the z axis direction. The system is handled as a system, and the plane that is the intermediate plane with respect to the fabric thickness h is considered to be the xy plane. The warp yarns are arranged in order from left to right, and the weft yarns are arranged in order from bottom to top.The leftmost warp and the lower weft are considered to be the 0th warp and weft, respectively. To express. The matrix that represents the organization chart information is defined as W (i, j). In the case of using a structure chart in which one circulation structure is composed of m warps and n wefts as the structure to be modeled, the ranges of the matrix subscripts are 0 ≦ i <m and 0 ≦ j <n. In addition, the value of the matrix takes a value of 1 in the case of elevating, and takes a value of 0 in the case of erecting.

  As a precondition for the modeling process 106, the yarn structure in the woven fabric has the structure of the Peirce model (Peirce FT; "The Geometry of Cloth Structure", J. Text. Inst., 28, T45 (1937)). Assume. Here, Peirce treats the warp and weft in the woven fabric as having the same thickness, but in the present embodiment, as shown in FIG. Considering that the yarn is used, the radius of the i-th warp from the left is represented by r1 (i), and the radius of the j-th weft from the bottom is represented by r2 (j). Similarly, the diameters of the warp and the weft are represented by d1 (i) and d2 (j), respectively. Further, the warp interval and the weft interval are expressed as P1 and P2, respectively.

Now, when the yarn in the fabric is represented by a Bezier curved surface, the cross section of the yarn is represented by a Bezier curve. An nth-order Bezier curve r0 (t; n) using a parameter t can be expressed by the following equation (1).

Here, Cn · i is a binomial coefficient and is equal to n! / {I! (Ni)!}. Also, pi is a vector indicating the control point coordinates of the Bezier curve, and is pi (x, y, z) in the three-dimensional space, and the subscript 0 of r0 indicates that the first control point is p0. The most frequently used cubic Bezier curve r0 (t; 3) is

It is necessary to give four control points p0, p1, p2 and p3 to express one curve.

On the other hand, a 3 × 3 order Bezier curved surface s00 (u, v; 3,3) using parameters u and v is expressed by the following equation.

Here, pi, j is the control point coordinates of the Bezier curved surface as in the case of the Bezier curve, and the subscript 00 of s00 indicates that the first control point is p0,0. In order to express one curved surface consisting of four sides, a 4 × 4 control point group is required. Therefore, 12 bezier surfaces are required to express the bending of the thread in the unit cell in the Peirce model, and the coordinates of 192 control points are specified using 120 coordinate points, and a Bezier surface is created. Thus, the three-dimensional shape of the yarn in the woven fabric can be determined.

Based on the above, the details of the processing for executing the modeling processing 106 using a cubic Bezier surface will be described with reference to FIGS.
FIG. 4 is a flowchart showing details of the modeling process 106 of FIG. 2, and FIG. 5 is an explanatory diagram showing the state of the cross section of the yarn at the intersection point.

First, in order to indicate the bending state of a thread using a Bezier curved surface, it is necessary to obtain the coordinates of the thread at the tissue point (i, j) in advance, and obtain the control point coordinate group of the Bezier curved surface from these coordinates. In particular, regarding the z coordinate of the yarn at the texture point (i, j), the vertical relationship of the yarn must be determined according to the information of the texture chart. Therefore, first, the x coordinate x1 (i, j), the y coordinate y1 (i, j) of the warp, the x coordinate x2 (i, j) and the y coordinate y2 (i, j) of the weft are obtained (S201). Here, the interval between the i-th warp and the i-1th warp is P1 (i), and the interval between the jth weft and the j-1 weft is P2 (j). The warp x coordinate x1 (i, j), y coordinate y1 (i, j), weft x coordinate x2 (i, j) and y coordinate y2 (i, j) at the tissue point (i, j) are respectively It can be expressed by the following formula.

  On the other hand, the z coordinate of the yarn at the texture point (i, j) is a flat woven fabric such as a Mihara texture, or a multi-layered structure such as a double weave, or a three-dimensional structure such as a honeycomb weave. It depends on whether it is an organization. This is because, in the latter case, the number of floating yarn structures affects the yarn height. Therefore, before obtaining the z-coordinate, first, the relative height is calculated from the number of floating yarn structures (S202), and the control point coordinates at the structure point are calculated according to the calculation result.

The number F1 (i) of the floating yarn structure of the i-th warp is obtained by the following equation, and F1 is a sequence in which each element takes an integer value between 0 and n.

On the other hand, assuming that the relative height in the fabric is H1 (i), H1 (i) is obtained from the sequence F1 by the following equation.

Here, min (s) is a function that returns the minimum value of the sequence s, and max (s) is a function that returns the maximum value. Equation (7) is valid when max (F1) ≠ min (F1), but when max (F1) = min (F1), it is considered that the relative height of all warps in the fabric is the same. So you can

Can be considered. The range of the relative height H1 (i) to be obtained is −0.5 ≦ H1 (i) ≦ 0.5, and the yarn height h1 (i) in the fabric can be obtained from the thickness h of the fabric by the following equation.

Also, in the case of wefts, as with warps, the number of floating yarn structures of the jth weft is F2 (j)

And the relative height H2 (j) of the weft in the fabric is max (F2) ≠ min (F2)

When max (F2) = min (F2)

It becomes. Further, the height h2 (j) of the weft in the woven fabric is obtained as follows.

Based on the yarn height obtained as described above, it is determined whether or not all the yarns in the woven fabric have the same height, that is, a flat woven fabric (S203). When all the yarns have the same height (S203: YES), the z-coordinate z1 (i, j) of the warp at the texture point (i, j) and the z-coordinate z2 (i, j) of the weft are shown in FIG. As shown in FIG. 5, the distance from the xy plane, which is an intermediate surface with respect to the fabric thickness h, to the center of the yarn axis of the warp yarn corresponds to the radius r2 of the weft yarn, so the following equations (14) and (15 ) To obtain the z coordinate of the yarn at the texture point (i, j) (S204).

Here, sgn (x) is a sign function defined by sgn (x) = {1 (x> 0)}, {-1 (x <0)}.

  On the other hand, when the yarn height is different in the woven fabric (S203: NO), the z coordinate of the yarn cannot be obtained from the above equations (14) and (15). Therefore, it is necessary to obtain the z coordinate of the yarn using the warp height h1 (i) and the weft height h2 (j) in the fabric obtained in S202.

First, at the texture point (i, j), it is determined whether or not the heights of the i-th warp and the j-th weft are the same (S205). When the heights of the i-th warp and the j-th weft are the same, that is, when h1 (i) = h2 (j) (S205: YES), the z-coordinate z1 (i, j) of the warp and The z coordinate z2 (i, j) of the weft is expressed by the following equations (16) and (17) from the equations (14) and (15).

Further, when the heights of the i-th warp and the j-th weft are different, that is, when h1 (i) ≠ h2 (j) (S205: NO), first, the relative of the yarn obtained in S202 is determined. By checking the relationship between the height and the radius of the warp and the weft, it is checked whether a yarn interference has occurred (S207). Here, when the following equation holds, it can be considered that the warp and the weft do not interfere (S207: YES).

  If the equation (18) is satisfied (S207: YES), then the matrix W (whether or not the vertical relationship between the warp and the weft on the organization chart and the relative height of the yarn determined in S202 are the same. Judgment is made by examining the relationship between the value of i, j) and the difference in relative height (S208, S209, S210).

When Formula (18) is satisfied, when warp floats, that is, W (i, j) = 1 (S208: YES) and the height of the warp is higher than the weft, that is, h1 (i)> h2 (j) ( S209: YES) or weft floating, ie, W (i, j) = 0 (S208: NO), and the height of the weft is higher than the warp, that is, h1 (i) <h2 (j) (S210 : YES), it can be said that the vertical relationship of the yarns specified in the organization chart and the magnitude relationship of h1 (i) and h2 (j) match. Accordingly, h1 (i) and h2 (j) may be set as the z-coordinates of the warp and the weft, respectively (S211), and can be expressed by the following equation.

Except for the above conditions (S208: NO, S210: NO, or S208: YES, S209: NO), the warp and the weft interfere with each other, or the positional relationship is opposite to the vertical relationship specified in the organization chart. Therefore, the process proceeds to the determination of whether or not interference has occurred, and to the interference determination / avoidance process (S212, S213) for executing the interference avoidance process if it has occurred.
The details of the interference determination / avoidance process are described in detail in the already filed patent application (Japanese Patent Application No. 2005-24609), and the description thereof is omitted here. Then, the modeling process is completed and the process returns to the process of FIG.

Next, before proceeding to the explanation of deformation simulation when a three-dimensional modeled fabric is pulled and bent, the deformation characteristics of the yarns constituting the fabric will be examined.
Many researchers have reported that the deformation characteristics of fabrics such as tension are greatly affected by the tensile and compression behavior of the yarns that make up the fabric. Therefore, since it is necessary to know the deformation characteristics of the shape due to the external force of the yarn in order to perform the simulation of the fabric deformation, the tensile deformation and the compression deformation of the polyester multifilament yarn were measured.
A tensile deformation test apparatus 301 as shown in FIG. 6 was used to conduct a tensile test on the yarn at a chuck distance of 200 mm and a tensile speed of 20 cm / min. The change in outer diameter at this time is shown in FIG. While measuring with the sensor 302, the compression deformation test was performed with the compression deformation test device 303. For compressive deformation, a load was applied to the yarn sandwiched between the glass plates from above, the thickness change observed from above the yarn was measured with a video microscope, and the thickness change observed from the side surface was measured using a laser displacement meter. Measured. The load at this time was measured with an electronic balance. The above tensile test results are shown in FIGS.

FIG. 8 shows the test results when the twist coefficients are the same (33.8) and the linear densities are different. FIG. 9 shows the test results when the linear density is the same (300D) and the twist coefficients are different.
Although the outer diameter decreases as the tension increases, the outer diameter does not change much even if the tension is increased from a certain point. This is presumably because the gap between the fibers is large in the low tension state, and when the gap approaches the limit, the change in the outer diameter is not observed. Further, if the twisting factor is increased, it is considered that the change in the outer diameter is small because the gap is already small in the low tension state.

Next, the compression test results described above are shown in FIGS.
The horizontal axis represents the compressive load per unit length of the yarn (cN / mm), and the vertical axis represents the ratio of the diameter d0 to the compressed thickness d1 assuming that the initial yarn cross section is circular. FIG. 10 shows the experimental results of yarns having a common twisting coefficient of 33.8 and different counts. FIG. 11 shows experimental results when the twisting coefficients are different when the count is the same as that of 300D. In either case, the initial tension was 9.8 cN. FIG. 12 shows experimental results of yarns having the same count (300D) and twisting coefficient (33.8) but different initial tensions. 10, 11, and 12, both the thickness and the thickness change greatly with an increase in the compressive load at a low compressive load, but the changes in both the thickness and the thickness are small at a high compressive load. From FIG. 10, it can be seen that even if the count is different, the rate of change is almost the same in both thickness and thickness, and thus the count does not affect the compression characteristics. As shown in FIG. 11, the yarn having a larger twist coefficient has a smaller rate of change in both thickness and thickness than a yarn having a smaller twist coefficient. Therefore, the twist coefficient affects the compression characteristics. Further, in FIG. 12, it was confirmed that the rate of change in both thickness and thickness decreased as the initial tension increased, and that the rate of change in thickness and thickness hardly changed in the high tension state.
From the above, it is considered that the fiber voids in the yarn change due to the change in elongation tension and the difference in twisting coefficient, and the compression characteristics differ due to this difference in structure.

  In this test, since compression was performed from above, the cross section at the time of compression was cut and observed, and the cross-sectional shape was asymmetrical in the vertical direction. This is thought to be due to the fact that the yarn is not a continuous body but a collection of fibers. As a result of creating software that simulates the movement of fibers in the yarn during compression and reproducing the deformation behavior of the cross section of the yarn. As shown in FIG. 13, a shape close to the cross-sectional shape at the time of actual compression could be obtained. By using this yarn deformation simulation method, it is possible to simulate the shape of the yarn in the fabric when the fabric is not deformed.

Next, in order to realize a simulation of fabric deformation with the yarn shape changed with external force, a deformation processing algorithm with collision / deformation judgment reflecting the yarn shape was constructed.
In an already applied patent (Japanese Patent Laid-Open No. 2006-274521), uniaxial stretching deformation in the warp direction and the weft direction is modeled. For this deformation, the following two-stage behavior was modeled.
Phase 1: As the fabric is stretched, the crimp of the yarn in the tensile direction is straightened. At this time, since the crimp height of the yarn in the pulling direction is lowered, the orthogonal yarn is pulled and contracts in the lateral direction.
Phase 2: After the crimp of the yarn in the tensile direction is straightened, the fabric is stretched according to the stretch characteristics of the yarn in the tensile direction itself.

On the other hand, the present invention assumes the case of biaxial extension, and even in this case, it is considered that the warping direction and the weft direction similarly show two stages of deformation behavior, and the deformation behavior has the following four modes. Conceivable.
Mode 1: Deformation behavior of Phase 1 in both warp and weft directions Mode 2: Deformation behavior of Phase 1 in the warp direction and Phase 2 in the weft direction Mode 3: Deformation behavior in Phase 2 of the warp direction and Phase 1 of the weft Mode 4 : Deformation behavior of phase 2 in both warp and weft directions At this time, mode 1 has a warp and warp structure, mode 2 has a warp bend structure, and mode 3 has a weft bend structure. Further, since mode 4 is inconsistent with the fabric structure, only the deformation behavior of mode 1 to mode 3 is considered, and the deformation of mode 4 is treated as a region exceeding the structural limit.

Fig. 14 (a) is a front view before the fabric is stretched, and Fig. 14 (b) is a front view when the fabric is stretched by 25% simultaneously in the warp direction and the weft direction. In the case of bending, in the conventional method for bending, the radius of curvature is handled from a circle in contact with the curved surface. However, the radius of curvature is handled as a sphere in contact with the curved surface. Since compressive stress is applied on the inner side, a process of deforming the cross section of the yarn orthogonal to the bending direction was added to cope with biaxial bending.
FIG. 15 shows an example of deformation calculation for biaxial bending of a fabric.

In the application of the present invention, as described above, the tensile deformation and compression deformation characteristics of the yarn, which are the basic parameters of the fabric deformation, are examined, and the structural parameters of the yarn, such as the yarn count and the twist coefficient, are determined when the yarn is tensioned and compressed. We analyzed the effect on the shape change.
As a result, it was confirmed that the fiber voids in the yarn changed due to the change in elongation tension and the difference in twist coefficient, and the compression characteristics differed due to the difference in structure. Based on the yarn deformation behavior measured above, a new three-dimensional modeling algorithm was constructed to reconstruct the three-dimensional model according to changes in the fabric structure during tensile and bending deformation. As a result, three-dimensional modeling of the internal structure of the fabric during deformation is possible. By applying the deformation characteristics of the yarn and the three-dimensional simulation method of the fabric during deformation, CAE can be realized in the fabric design. It is considered that advanced textile design for realizing high-performance characteristics required for end use such as industrial textiles will be possible.

In order to realize the simulation of the fabric deformation, the three-dimensional modeling process of the fabric structure of FIG. 2 was improved and a deformation processing algorithm was constructed. A flowchart of the algorithm is shown in FIG.
A three-dimensional unit structure model 107 of the fabric is generated by the modeling process 106 from the fabric structure chart 101 and the given fabric design information 105. With respect to the generated three-dimensional unit structure model 107 of the woven fabric, the elongation ratios ε ₁ and ε ₂ (141) and the curvatures κ ₁ and κ ₂ (142) are designated in advance by condition division numbers _ne and n _r (143). A number of deformation conditions are given, and a fabric unit structure deformation database 150 is created in which n _e × n _e tensile model data and n _r × n _r bending model data are accumulated by a fabric unit structure deformation calculation 145.
Subsequently, the curved surface information after the product formation is prepared as 3D CAD data 161 created by general-purpose 3D CAD or the like. The target curved surface is converted into a Bezier curved surface from the CAD data 161 of the read product shape, and the curved surface division processing 162 is performed according to the division law of the Bezier curved surface for each size of the fabric structure, and the warp direction s ₁ and the weft direction s ₂ It is divided into a total of s ₁ × s ₂ areas. The de Casteljau algorithm is used for the division law of the Bezier surface. The path length of the boundary line of each region and the curvature at the center point of the region are calculated for a total of s ₁ × s ₂ minute regions, and the curved surface deformation prediction calculation 163 forms the shape of the 3D CAD data 161. In this case, the deformation shape of the fabric is obtained. In the curved surface deformation prediction calculation 163, the 3D unit structure model 107 of the path length of the boundary line of each region and the curvature at the center point of the region is retrieved from the fabric unit structure deformation database 150 and output. By superimposing these over the entire region, the deformed shape of the entire curved surface can be obtained.

The calculation of the path length of the boundary line of each region performed in the curved surface deformation prediction calculation 163 will be described.
In general, the length of the section of the spatial curve that is the parametric representation is

Can be expressed as In the present invention, each region is handled as a Bezier curved surface, so the boundary line of each region is a cubic Bezier curve.

Therefore, the length of the curved portion can be obtained by obtaining an ordinary differential equation obtained by applying Equation (22) to Equation (21). Since it is difficult to find a solution of an ordinary differential equation in actual calculation, it was obtained by numerical calculation using the forward Euler method.
FIG. 17 shows a flowchart of the route calculation process.

Next, the fabric unit structure deformation calculation 145 will be described.
FIG. 18 shows a flowchart of the fabric unit structure deformation calculation 145. Organizational chart W (i, j) of m × n size {0 ≦ i <m, 0 ≦ j <n} The deformation process is applied to the fabric 3D model Mo (i, j) created by the conventional method (S501). And output the deformed three-dimensional fabric model M (i, j) (S514). At this time, if the designated deformation mode is the pure bending deformation mode, the bending deformation calculation is executed, and if the designated deformation mode is the tensile deformation mode, the tensile deformation calculation is executed (S502). As for the bending deformation, a pure bending deformation process in the warp direction (S503) and a pure bending deformation process in the weft direction (S504) are sequentially calculated.

Next, processing when the deformation mode specified in (S502) is tensile deformation will be described.
Lw0 and Lf0 are the fabric lengths in the warp and weft directions before deformation, Lw1 and Lf1 are the fabric lengths in the warp and weft directions after deformation, and Lwy0 are the warp and weft directions before deformation. And Lfy0.
First, the yarn length of each yarn is calculated for the fabric three-dimensional model Mo (i, j) created by the conventional method (S501) (S505). Then, after comparing the fabric length Lw1 in the warp direction after deformation with the yarn length Lwy0 in the warp direction before deformation (S506), the fabric length Lf1 in the weft direction after deformation and the weft direction in the weft direction before deformation are compared. The thread length is compared with Lfy0 (S507 and S508).

In the case of Lw1 ≦ Lwy0 and Lf1 ≦ Lfy0, it is considered that the deformation behavior of mode 1, that is, the deformation behavior of phase 1 in both the warp direction and the weft direction, and the tensile deformation processing procedure 1 (S509) was performed in the warp direction. Thereafter, the tensile deformation processing procedure 1 (S510) is performed in the weft direction, and the deformed woven fabric three-dimensional model is output (S514).
On the other hand, when Lw1 ≦ Lwy0 and Lf1> Lfy0, it is considered that the deformation behavior of mode 2, that is, the warp direction shows the deformation behavior of phase 1 and the weft direction shows the deformation behavior of phase 2, and the tensile deformation processing procedure 1 ( After carrying out S509), the tensile deformation processing procedure 2 (S511) is carried out in the weft direction, and output as a woven fabric three-dimensional model after deformation (S514).
Further, when Lw1> Lwy0 and Lf1 ≦ Lfy0, it is considered that the deformation behavior of mode 3, that is, the warp direction shows the deformation behavior of phase 2 and the weft direction shows the deformation behavior of phase 1, and the tensile deformation processing procedure 2 ( After carrying out S512), the tensile deformation processing procedure 1 (S510) is carried out in the weft direction, and output as a woven fabric three-dimensional model after deformation (S514).
If Lw1> Lwy0 and Lf1> Lfy0, the deformation behavior of mode 4 and the warp and weft directions are considered to be the deformation behavior of phase 2, but this state is inconsistent with the fabric structure, so the region exceeds the structural limit. And the parent routine is notified that the calculation is impossible (S513).

Next, the yarn length calculation algorithm will be described.
In any of the above processing procedures, the yarn length in the woven fabric is calculated. In the yarn length calculation, as shown in FIG. 19, a method of calculating the yarn length by linearly approximating the crimp of the yarn, and as shown in FIG. 20, calculating the yarn length without linearly approximating the crimp of the yarn. A method can be considered. In the former, since an error occurs in the model after deformation in the tensile deformation processing procedure 1 (S509 and S510), a method of calculating the yarn length without linearly approximating the crimp of the latter yarn is used.
In the present invention, the bending of the yarn in the woven fabric is modeled using a cubic Bezier curve, so that the yarn according to the flowchart shown in FIG. It becomes possible to calculate the length.

Next, algorithms for the warp direction tensile deformation processing procedure 2 (S512) and the weft direction tensile deformation processing procedure 2 (S511) will be described.
When Lw1> Lwy0 at the time of tensile deformation in the warp direction (S512), after the crimp of the yarn in the tensile direction becomes straight, the fabric is stretched according to the stretch characteristics of the yarn in the tensile direction itself. Lw1> under the conditions of Lwy0, when performing only stretch deformation expansion ratio epsilon ₁ the fabric in the warp direction, tissue point W (i, j) the warp coordinates in {x1 (i, j), y1 (i, j), z1 (i, j)} and the coordinates of the weft are {x2 (i, j), y2 (i, j), z2 (i, j)}. 1 (i, j), y''1 (i, j), z''1 (i, j)} and transformed weft coordinates {x''2 (i, j), y''2 (i , j), z''2 (i, j)}
x``1 (i, j) = x1 (i, j) (23)
y''1 (i, j) = y1 (i, j) ・ {1 + ε <sub>1</sub> } (24)
z''1 (i, j) = 0 (25)
x``2 (i, j) = x2 (i, j) ・ (26)
y''2 (i, j) = y2 (i, j) ・ {1 + ε ₁ } (27)
z``2 (i, j) = sgn {W (i, j) -1/2} ・ {r1 (i) + r2 (j)} / 2 (28)
It becomes.

FIG. 21 shows a flowchart of the tensile deformation processing procedure 2.
Expressions (24) and (26) correspond to (S603) in FIG. 21, Expression (25) corresponds to (S604), and Expression (28) corresponds to (S605).
Note that the tensile deformation processing procedure 2 in the weft direction (S511) is also handled as a case where the fabric is stretched and deformed in the weft direction by an elongation ratio ε ₂ under the condition of Lf1> Lfy0, and the texture point W (i, j ) For warp yarn coordinates {x1 (i, j), y1 (i, j), z1 (i, j)} and weft coordinates {x2 (i, j), y2 (i, j), z2 ( i, j)}, the warp coordinates {x''1 (i, j), y''1 (i, j), z''1 (i, j)} after deformation and the weft after deformation The coordinates {x''2 (i, j), y''2 (i, j), z''2 (i, j)} are respectively
x``1 (i, j) = x1 (i, j) ・ {1 + ε <sub>2</sub> } (29)
y''1 (i, j) = y1 (i, j) (30)
z``1 (i, j) = 0 (31)
x``2 (i, j) = x2 (i, j) ・ {1 + ε ₂ } (32)
y''2 (i, j) = y2 (i, j) (33)
z''2 (i, j) = sgn {W (i, j) -1/2} ・ {r1 (i) + r2 (j)} / 2 (34)
It becomes.
In this case, Expression (30) and Expression (32) correspond to (S603) in FIG. 21, Expression (31) corresponds to (S604), and Expression (34) corresponds to (S605).

Next, algorithms of the warp direction tensile deformation processing procedure 1 (S509) and the weft direction tensile deformation processing procedure 1 (S510) will be described.
FIG. 22 shows a flowchart of the tensile deformation processing procedure 1.
When Lw1 ≦ Lwy0 during tensile deformation in the warp direction, the crimp of the yarn in the tensile direction becomes straight as the fabric is stretched. At this time, since the crimp height of the yarn in the pulling direction is lowered, the orthogonal yarn is pulled. When the fabric is stretched and deformed in the warp direction by the stretch ratio ε ₁ under the condition of Lw1 ≦ Lwy0, the coordinates of the warp at the texture point W (i, j) are expressed as (x1 (i, j), y1 (i, j), z1 (i, j)}, the coordinates of the weft are {x2 (i, j), y2 (i, j), z2 (i, j)}, the warp coordinates {x'1 (i, j, j), y'1 (i, j), z'1 (i, j)} and the transformed weft coordinates {x'2 (i, j), y'2 (i, j), z'2 ( i, j)}. In the tensile deformation treatment procedure 1, the crimp height h of the yarn in the tensile direction is an extreme value between the height h1 in the state of the tensile deformation treatment procedure 2 and the height h2 in a state in which the coordinate conversion is simply performed by the elongation ratio. The deformation model in the intermediate state is sequentially created, and the optimum thread height h is obtained by numerical calculation. The Brent algorithm was used for the solution by numerical calculation here.

  First, a fabric three-dimensional model Mo (i, j) in a state before deformation is created, and coordinate transformation is performed on Mo (i, j) using equations (24) to (34) according to the processing flow of FIG. A three-dimensional fabric model M1 (i, j) subjected to the conversion process of the tensile deformation process procedure 2 is generated (S701). The yarn length L0 (i) of each warp is calculated by the procedure shown in FIG. 17 (S702). Further, the height of each warp at this time is set to h0 (i) (S703). In this case, it is clear that h0 (i) = z ″ 1 (i, j) = 0 for all warps when the processing of the tensile deformation processing procedure 2 is performed.

Subsequently, coordinate transformation is performed from the fabric three-dimensional model Mo (i, j) using equations (35) to (41) according to the processing flow of FIG. 23, and the fabric 3 in a state where the coordinate transformation is simply performed by the stretch rate. After generating the dimensional model M2 (i, j) (S704), the yarn length L2 (i) of each warp is calculated by the procedure shown in FIG. 17 (S705). In addition, the height of each warp at this time is set as h2 (i) (S706).
x``1 (i, j) = x1 (i, j) (35)
y''1 (i, j) = y1 (i, j) ・ {1 + ε <sub>1</sub> } (36)
z``1 (i, j) = z1 (i, j) (37)
x``2 (i, j) = x2 (i, j) (38)
y''2 (i, j) = y2 (i, j) ・ {1 + ε <sub>1</sub> } (39)
z``2 (i, j) = z2 (i, j) (40)
h2 = | z''1 (i, j) | (41)
At this time, the optimum yarn crimp height h is obtained by numerical calculation, and h1 <h <h2 is applied as a boundary condition for numerical calculation. Further, a fabric three-dimensional model having an arbitrary h is Mh (i, j), and the yarn length at this time is Ly (h). Warp coordinates {x '''1 (i, j), y''' 1 (i, j), z '''1 (i, j)} and the weft coordinates after deformation {x '''2 (i, j), y''' 2 (i, j), z '''2 (i, j)}
x``'1 (i, j) = x1 (i, j) (42)
y '''1 (i, j) = y1 (i, j) ・ {1 + ε} (43)
z '''1 (i, j) = sgn {W (i, j) -1/2} ・ h (44)
x``'2 (i, j) = x2 (i, j) (45)
y '''2 (i, j) = y2 (i, j) {1 + ε} (46)
z '''2 (i, j) = z2 (i, j) −sgn {W (i, j) -1/2} ・ h (47)
It becomes.

After conversion, the yarn length Ly (i, h) of each warp is calculated according to the procedure shown in FIG. FIG. 24 shows a procedure for generating a three-dimensional woven fabric model for an arbitrary h.
In the tensile deformation treatment procedure 1, since the crimp of the yarn in the tensile direction becomes straight as the fabric is stretched, it can be considered that the yarn length before the deformation hardly changes. Therefore, between the yarn length before deformation and the yarn length Ly (i, h) after coordinate conversion, g (i, h) = Ly (i, h) −Ly0 = 0 (48)
Therefore, h satisfying the equation (42) is obtained by numerical calculation. A processing flow for calculating the optimum h is shown in FIG. Using the obtained h, coordinate transformation is performed from Mo (i, j) using equations (42) to (47) to obtain a deformed fabric three-dimensional model M (i, j) (708).
Also in the weft direction tensile deformation processing procedure 1 (S510) based on the case where the fabric is stretched and deformed in the weft direction by the stretch ratio ε ₂ under the condition of Lw1 ≦ Lwy0, the warp direction tensile deformation processing procedure is also used. 1 (S509) The same concept can be applied.

Next, the bending deformation calculation process (S503) in the warp direction and the bending deformation calculation process (S504) in the weft direction will be described.
As for the warp direction bending deformation calculation processing (S503), a case is considered in which pure bending of the woven fabric is performed in the warp direction by a curvature radius r ₁ . Curvature κ ₁ is a κ ₁ = ₁ / r ₁ from the definition. In this case, if the coordinates before deformation in the i-th warp at the texture point W (i, j) are set as {x1 (i, j), y1 (i, j), z1 (i, j)}, Coordinates {xb1 (i, j), yb1 (i, j), zb1 (i, j)} are respectively θ1 = κy1 (i, j) (49)
xb1 (i, j) = x1 (i, j) (50)
yb1 (i, j) = (z1 (i, j) + r ₁ ) sin (θ1) (51)
zb1 (i, j) = − (r ₁ − (z1 (i, j) + r ₁ )) cos (θ1) (52)
The coordinates {xb2 (i, j), yb2 (i, j), zb2 (i, j)} of the j-th weft at the texture point W (i, j) are θ2 = κy2 (i , j) (53)
xb2 (i, j) = x2 (i, j) (54)
yb2 (i, j) = (z2 (i, j) + r ₁ ) sin (θ2) (55)
zb2 (i, j) = − (r ₁ − (z2 (i, j) + r ₁ )) cos (θ2) (56)
It becomes.

Similarly, for the weft direction of the bending deformation calculation process (S504), consider a case where the bending fabric only radius of curvature r ₂ net the weft direction. Curvature kappa ₂ becomes κ ₂ = 1 / r ₂ from the definition. In this case, the coordinates {xb1 (i, j), yb1 (i, j), zb1 (i, j)} of the i-th warp at the texture point W (i, j) are respectively θ1 = κy1 ( i, j) (57)
xb1 (i, j) = (z1 (i, j) + r ₂ ) sin (θ1) (58)
yb1 (i, j) = y1 (i, j) (59)
zb1 (i, j) = − (r ₂ − (z1 (i, j) + r ₂ )) cos (θ1) (60)
The coordinates {xb2 (i, j), yb2 (i, j), zb2 (i, j)} of the j-th weft at the texture point W (i, j) are θ2 = κy2 (i , j) (61)
xb2 (i, j) = (z2 (i, j) + r ₂ ) sin (θ2) (62)
yb2 (i, j) = y2 (i, j) (63)
zb2 (i, j) = − (r ₂ − (z2 (i, j) + r ₂ )) cos (θ2) (64)
It becomes. Coordinate transformation is performed from Mo (i, j) using equations (49) to (64) to obtain a three-dimensional woven fabric model Mb (i, j) after bending deformation (S514).

Next, creation of an application will be described.
Based on the algorithm for calculating tensile deformation with the above improvements, software was created to output a three-dimensional fabric model at the time of deformation. For software development, Microsoft (registered trademark) VisualBASIC.NET (modeler part) and VisualC ++. NET (viewer part) were used, and the software was constructed on the assumption of operation on Windows (registered trademark) XP.
The 3D shape data of the curved surface shape was actually given, and the strain distribution of the fabric when it was deformed to the specified curved surface was calculated. The calculation conditions were a plain weave fabric with a weaving density of 50 / inch using 1/30 Nm polyester and pressed against a hemisphere with a radius of curvature of 16.7 mm (curvature 0.06 mm ⁻¹ ) shown in FIG. The woven fabric shape and strain distribution were calculated.
FIG. 27 shows the shape of the woven fabric after deformation, and FIG. 28 shows the strain distribution at this time. Thus, it was confirmed that the strain amount distribution can be calculated for the fabric when deformed to the designated curved surface. In addition, it is considered that the calculation accuracy can be improved and the calculation processing speed can be increased by using it together with an existing deformation analysis method such as the finite element method.

  As described above, in the present invention, in order to predict the amount of distortion generated when a woven fabric is processed into a curved shape, the woven fabric is divided into a plurality of minute regions, and the woven fabric is determined from the physical properties of the yarn and the design conditions of the woven fabric for each minute region. By calculating the internal three-dimensional structure and microdeformation characteristics, applying the multi-scale analysis to overlay the results, and predicting and calculating the amount of distortion of the entire fabric processed into the final product shape, It is possible to design an optimal fabric that does not cause wrinkles or excessive tension when it is made into the shape of the final product from yarns of any material and thickness and design conditions without trial and error trial production. Become.

It is a block diagram which shows the electrical structure of the computer which functions as a 3D model construction method of a fabric, and a 3D model construction apparatus of a fabric. It is a flowchart which shows the flow of the three-dimensional modeling process of a textile fabric. It is explanatory drawing which shows the state of the cross section of the thread | yarn in the crossing point in a Peirce model. It is a flowchart which shows the detail of the modeling process of FIG. It is explanatory drawing which shows the state of the cross section of the thread | yarn in a crossing point. It is explanatory drawing for testing the deformation | transformation characteristic of a thread | yarn with a tensile deformation test apparatus. It is explanatory drawing for testing the deformation | transformation characteristic of a thread | yarn with a compression deformation test apparatus. It is the graph which showed the result of having tested the deformation | transformation characteristic of the thread | yarn with the tension deformation test apparatus. It is the graph which showed the result of having tested the deformation | transformation characteristic of the thread | yarn with the tension deformation test apparatus. It is the graph which showed the result of having tested the deformation | transformation characteristic of the thread | yarn with the compression deformation test apparatus. It is the graph which showed the result of having tested the deformation | transformation characteristic of the thread | yarn with the compression deformation test apparatus. It is the graph which showed the result of having tested the deformation | transformation characteristic of the thread | yarn with the compression deformation test apparatus. It is a simulation figure of the section shape accompanying compression of a thread. (A) is a front view of the yarn before the fabric is stretched, and (b) is a front view of the yarn when the fabric is stretched by 25% simultaneously in the warp and weft directions. It is a simulation figure at the time of bending a woven fabric simultaneously in the warp and weft directions. It is a main flowchart of the biaxial deformation simulation of a textile fabric. It is a flowchart of yarn length calculation. It is a main flowchart of the biaxial deformation simulation of a textile fabric. It is thread length calculation explanatory drawing of a Peirce model. It is thread length calculation explanatory drawing of a Peirce model. It is a subroutine flowchart of the flowchart of FIG. It is a subroutine flowchart of the flowchart of FIG. It is a subroutine flowchart of the flowchart of FIG. It is a subroutine flowchart of the flowchart of FIG. It is a subroutine flowchart of the flowchart of FIG. It is a perspective view of the hemispherical surface which presses a textile fabric. It is the output display figure which showed the three-dimensional model production | generation result of the textile fabric. It is an output display figure showing distortion amount distribution of textiles.

Explanation of symbols

1 Computer 30 Display Control Unit 31 Monitor 40 Input Detection Unit 41 Keyboard 42 Mouse 50 CPU
60 HDD
61 Program storage area 62 Database storage area 106 Modeling process 130 3D shape image

Claims (12)

Using the fabric structure data, the fabric standard data including at least one of the fabric density and the yarn thickness, and the physical property data of the yarn including at least one of the tensile properties and compression properties of the yarn as input values, A step of performing three-dimensional modeling of the shape of each constituting yarn, a step of outputting a three-dimensional model of the fabric as an aggregate in which the shape of the yarn is assembled by the three-dimensional modeling, and the three-dimensional of the fabric Recalculating the fabric structure when the model is biaxially stretched to the specified warp direction elongation rate ε ₁ and weft direction elongation rate ε ₂ , and outputting the recalculated three-dimensional model of the fabric And a method for constructing a three-dimensional model of a woven fabric.   The step of recalculating the fabric structure in the case of biaxial stretching calculates the yarn weaving rate in each stretching direction from the three-dimensional model of the fabric before deformation, and the stretching rate in each direction is less than the weaving rate. The first recalculation process in the case of the above and the second recalculation process in the case where the expansion rate in each direction is greater than or equal to the weaving rate are automatically selected and recalculated. Item 3. A method for constructing a three-dimensional model of a fabric according to Item 1.   In the first recalculation process, as the stretch rate in each direction of the fabric increases, the yarn in the stretch direction in each direction of the fabric moves from the bent structure to the linear structure and the crimp height decreases. 3. The method for constructing a three-dimensional model of a woven fabric according to claim 2, wherein a three-dimensional model of the woven fabric is recalculated on the basis of a phenomenon in which a thread perpendicular to each stretching direction is pulled and contracted in the lateral direction.   The second recalculation process is based on a pre-measured yarn stress-strain curve, and takes into account the phenomenon in which the yarn stretch rate in each direction increases as the fabric stretch rate increases. The method for constructing a three-dimensional model of a woven fabric according to claim 2, wherein the model is recalculated. Using the fabric structure data, the fabric standard data including at least one of the fabric density and the yarn thickness, and the physical property data of the yarn including at least one of the tensile properties and compression properties of the yarn as input values, A step of performing three-dimensional modeling of the shape of each constituting yarn, a step of outputting a three-dimensional model of the fabric as an aggregate in which the shape of the yarn is assembled by the three-dimensional modeling, and the three-dimensional of the fabric Recalculate the fabric structure when the model is bent to a specified warp direction curvature κ ₁ or warp direction curvature radius 1 / κ ₁ and weft direction curvature κ ₂ or weft direction curvature radius 1 / κ ₂ And a step of outputting the recalculated three-dimensional model of the fabric. A method for constructing a three-dimensional model of the fabric. For the specified arbitrary curved surface, the basic unit structure of weave structure as a unit, the warp direction s ₁ piece, a step of dividing a total s ₁ × s ₂ regions consisting of _two weft direction s, divided The process of calculating the state deformed by modeling the woven structure according to claim 1 or 5 for each region, and the deformation state and stress distribution of the entire specified curved surface shape by superimposing them. A three-dimensional model of the woven fabric comprising: a step of calculating a strain amount distribution; and a step of outputting a three-dimensional model of the entire arbitrary curved surface shape of the calculated woven fabric, a stress distribution, and a strain amount distribution. Construction method. As an input value, the fabric specification data including at least one of the fabric structure diagram, the woven density of the fabric, and the thickness of the yarn and the physical property data of the yarn including at least one of the tensile property and the compression property of the yarn are used as input values. Under a biaxial tensile deformation at a combination of a plurality of warp direction elongation ratios ε ₁ and a plurality of weft direction elongation ratios ε ₂ at intervals, a plurality of warp direction curvatures κ ₁ or a warp direction curvature radius 1 / κ _1, and a three-dimensional model of the fabric under biaxial pure bending deformation generates a plurality at a plurality of weft direction curvature kappa ₂ or weft direction of the radius of curvature 1 / kappa ₂ in combination, the stress from these three-dimensional model and the distortion amount calculated, as well as accumulate these values in the database, for any curved surface is specified, the warp direction s ₁ pieces of basic unit structure of weave structure as a unit, from the _two weft direction s That total s ₁ × split s into _two regions, a state of being deformed from the database calculated for each divided region, these optional designated by overlaying the entire area curved shape overall The method for constructing a three-dimensional model of a woven fabric according to claim 6, wherein the deformation state, the stress distribution, and the strain amount distribution are calculated. Using the fabric structure data, the fabric standard data including at least one of the fabric density and the yarn thickness, and the physical property data of the yarn including at least one of the tensile properties and compression properties of the yarn as input values, 3D modeling means for performing 3D modeling of the shape of each constituting yarn, and 3D model output means for outputting a 3D model of the woven fabric as an aggregate in which the yarn shapes are assembled by the 3D modeling And recalculating the fabric structure when biaxially stretched to the specified warp direction elongation rate ε ₁ and weft direction elongation rate ε ₂ of the three-dimensional model of the fabric, and then recalculating the 3 And a recalculated three-dimensional model output means for outputting a three-dimensional model. Using the fabric structure data, the fabric standard data including at least one of the fabric density and the yarn thickness, and the physical property data of the yarn including at least one of the tensile properties and compression properties of the yarn as input values, 3D modeling means for performing 3D modeling of the shape of each constituting yarn, and 3D model output means for outputting a 3D model of the woven fabric as an aggregate in which the yarn shapes are assembled by the 3D modeling The warp direction curvature κ ₁ or the warp direction curvature radius 1 / κ ₁ , and the weft direction curvature κ ₂ or the weft direction curvature radius 1 / κ ₂ specified in the three-dimensional model of the fabric 3D model construction apparatus for fabric, comprising: a bending deformation 3D model output means for outputting the recalculated fabric 3D model after recalculating the fabric structure of the fabric . Dividing means for dividing a specified arbitrary curved surface shape into a total of s ₁ × s ₂ regions consisting of a warp direction s ₁ and a weft direction s ₂ with a basic unit structure of the woven fabric as one unit 6. A deformation state calculation means for calculating a state in which each region is deformed by modeling the woven fabric structure according to claim 1 or 5, and a deformation of the entire specified arbitrary curved surface shape by superimposing them. A state, stress distribution, strain amount distribution, and a three-dimensional model output unit for outputting the calculated three-dimensional model of the entire curved surface of the woven fabric, stress distribution, and strain amount distribution. A three-dimensional model construction device for textiles.   9. A recording medium on which a software program for executing the three-dimensional modeling means, the three-dimensional model output means, and the recalculated three-dimensional model output means described in claim 8 is recorded.   A recording medium on which a software program for executing the three-dimensional modeling means, the three-dimensional model output means, and the bending deformation three-dimensional model output means according to claim 9 is recorded.