JP2004139570A - Method of assisting wiring design of wiring structure, its apparatus and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and accurately perform optimum wiring design for a wiring structure in a short period of time without depending upon a designer's level of skill by sequentially calculating the shape of the wiring structure and outputting the results. <P>SOLUTION: This wiring structure 1a constituted of a plurality of line streak members is considered as an elastic body in which a plurality of beam elements whose linearity is maintained on a circular cross section are coupled with each other. A finite element method is used to output a predicted shape of the wiring structure satisfying a predetermined condition. Particularly, The aspects of deformation of the wiring structure, when an initial shape of the wiring structure is changed to the balanced final shape 1z of the wiring structure, are sequentially calculated by using the finite element method while satisfying the shape characteristics, material characteristics and constraining condition of the wiring structure, and the results are sequentially outputted. <P>COPYRIGHT: (C)2004,JPO

Description

The present invention relates to a method, an apparatus and a program for supporting a wiring design of a wire-like structure composed of a plurality of filaments, and particularly to an optimal wiring of a wire harness wired to a vehicle as a wire-like structure. The present invention relates to a method, a device, and a program for supporting a design.

Usually, in a vehicle or the like, a plurality of electric components are mounted, and these are so-called wire members, in which a plurality of electric wires and communication lines are bound by a binding member such as an insulation lock or a protection member such as a tape. , Connected by a wire harness. As shown in FIG. 1, the wire harness 1 has connectors 2a, 2b, 2c, and 2d connected to electrical components and the like at each end. Various clips 3a, 3b, 3c, and 3d are attached to an intermediate portion thereof, and a branch point 4 is further provided. In addition, since each branch line of the wire harness 1 which constitutes from each end to the branch point 4 basically differs in the number and types of constituent line members, the thickness, length and elasticity of each branch line are different. , Rigidity and the like are also various. Conventionally, wiring design of such a wire harness is often performed based on the intuition and experience of a designer.

Here, the references cited in this specification are shown below.
B. Eggplant, Matrix Finite Element Method, Brain Tosho Publishing Co., Ltd., August 10, 1978, p. 7-15

However, wire harnesses are diverse as described above, and it has been very difficult to accurately predict and design rigidity against bending and torsion in each of those parts. For this reason, it is often difficult to assemble as designed or to have an unrealistic shape. Therefore, in order to obtain the optimal wiring shape of the wire harness, design and assembly are repeated through trial and error, and a great deal of time is wasted. Further, according to such a method, a high degree of skill is required to perform an optimum wiring design.

Therefore, in view of the above-described current situation, the present invention sequentially calculates the predicted shape of a wire-like structure such as a wire harness and sequentially outputs the results, thereby making the optimum wiring design dependent on the skill of the designer. An object of the present invention is to provide a wiring harness wiring design support method, a device and a program thereof, which can be performed easily and accurately in a short period of time without performing.

In order to solve the above-mentioned problems, the wiring design support method for a wire-like structure according to claim 1, wherein the linearity of the wire-like structure composed of a plurality of filaments is maintained in a circular cross section. Considering an elastic body in which a plurality of beam elements are connected, by using a finite element method, predicting and outputting the shape of the wire-like structure satisfying a predetermined condition, optimal wiring of the wire-like structure A method for supporting a design, wherein information on the shape characteristics, material properties, and constraint conditions of the wire-like structure as the predetermined condition is applied to the finite element method so that the wire-like structure has an arbitrary initial shape. , The state of being transformed into a balanced final shape satisfying the predetermined condition is sequentially calculated, and the result is sequentially output.

According to the first aspect of the present invention, a wire-like structure including a plurality of filaments is regarded as an elastic body in which a plurality of beam elements having a circular cross section and maintaining linearity are connected. Then, the predicted shape of the wire-like structure that satisfies the predetermined condition is output using the finite element method. In particular, the state of the wire-like structure being transformed from the initial shape to the balanced final shape while satisfying the shape characteristics, material characteristics and constraint conditions of the wire-like structure is sequentially evaluated using the finite element method. The calculation is performed and the result is sequentially output.

According to a second aspect of the present invention, there is provided a wiring design support method for a wire-like structure according to the first aspect. It is characterized in that the state of deformation of the wire-like structure when displaced by applying a predetermined force is sequentially calculated, and the result is sequentially output.

According to the second aspect of the invention, the state of deformation of the wire-like structure when a predetermined portion of the wire-like structure is displaced by applying a force is sequentially calculated, and the result is sequentially output. .

The wiring design support method for a wire-like structure according to claim 3 made in order to solve the above-mentioned problem is a wiring design support method for a wire-like structure according to claim 1 or 2, wherein the wire-like structure is: A wire harness wired to a vehicle, wherein the constraint condition is coordinates of each vertex of the plurality of beam elements and a degree of freedom at each vertex, and the shape characteristic is a cross-sectional area of the beam element of the wire-like structure. And the length thereof, and the material properties are a second moment of area, a second moment of area, a density, a modulus of longitudinal elasticity, and a modulus of transverse elasticity of the beam element.

According to the invention described in claim 3, the constraint condition is the coordinates of each vertex of the plurality of beam elements constituting the wire-like structure and the degree of freedom at each vertex, and the shape characteristic is the cross-sectional area of the beam element of the wire-like structure. The material properties are the second moment of area, the second moment of area, the density, the modulus of longitudinal elasticity, and the modulus of transverse elasticity of the beam element.

The wiring design support method for a wire-like structure according to claim 4 made in order to solve the above-mentioned problem, by calculating a predicted shape related to wiring of a wire-like structure composed of a plurality of linear materials, In a method that supports the optimal wiring design of wire-like structures, the state in which the target wire-like structure is deformed from an arbitrary initial shape to a balanced final shape is sequentially calculated, and the results are output sequentially. To be characterized.

According to the fourth aspect of the invention, the state in which the target wire-like structure is deformed from the initial shape to the balanced final shape is sequentially calculated, and the result is sequentially output.

In order to solve the above-mentioned problem, the wiring design support apparatus for a wire-like structure according to claim 5 has a structure in which a wire-like structure composed of a plurality of filaments is kept linear in a circular cross section. Considering an elastic body in which a plurality of beam elements are connected, by using a finite element method, predicting and outputting the shape of the wire-like structure satisfying a predetermined condition, optimal wiring of the wire-like structure An apparatus that supports design, setting means for setting information on the shape characteristics of the wire-like structure as the predetermined conditions, material characteristics and constraints, and applying the predetermined conditions to the finite element method, Calculating means for sequentially calculating a state in which the wire-like structure is deformed from an arbitrary initial shape to a final shape that is balanced so as to satisfy the predetermined condition, based on a calculation result by the calculating means; Can sequentially the manner of deformation of the wire-like structure, characterized in that it comprises an output means for updating output, a.

According to the fifth aspect of the present invention, a wire-like structure composed of a plurality of filaments is regarded as an elastic body in which a plurality of beam elements having a circular cross section and maintaining linearity are connected. Then, the predicted shape of the wire-like structure that satisfies the predetermined condition is output using the finite element method. In particular, while satisfying the shape characteristics, material characteristics and constraint conditions of the wire-like structure, the deformation state of the wire-like structure when this wire-like structure is displaced from the initial shape to the balanced final shape is finite. The calculation is performed sequentially using the element method, and the result is sequentially output.

A wire design support apparatus for a wire-like structure according to claim 6, which is provided to solve the above problem, is a wiring design support apparatus for a wire-like structure according to claim 5, wherein the wire-like structure is provided as the predetermined condition. The apparatus further includes second setting means for setting a force to be applied to a predetermined portion of the object, wherein the calculating means sequentially calculates a state of deformation of the wire-like structure when the force is applied and displaced. And

According to the invention described in claim 6, the state of deformation of the wire-like structure when a predetermined portion of the wire-like structure is displaced by applying a force is sequentially calculated, and the result is sequentially output. .

The wiring design support device for a wire-like structure according to claim 7 made in order to solve the above-mentioned problem is characterized in that in the wiring design support device for a wire-like structure according to claim 5 or 6, a trigger based on a manual operation is provided. And a pause control unit for temporarily stopping the output of the output unit.

According to the seventh aspect of the invention, the output by the output means is temporarily stopped by the trigger based on the manual operation.

A wiring design support program for a wire-like structure according to claim 8, which has been made to solve the above-described problem, has a wire-like structure made up of a plurality of filaments that has a linear cross section in a circular cross section. Considering an elastic body in which a plurality of beam elements are connected, by using a finite element method, predicting and outputting the shape of the wire-like structure satisfying a predetermined condition, optimal wiring of the wire-like structure In order to support the design, the computer, a setting means for setting information on the shape characteristics of the wire-like structure as the predetermined conditions, material properties and constraint conditions, applying the predetermined conditions to the finite element method, Calculation means for sequentially calculating the state in which the wire-like structure is deformed from an arbitrary initial shape to a balanced final shape that satisfies the predetermined condition, by the calculation means Out on the basis of the results, the sequential states of deformation of the wiring structure, an output means for updating the output to function as it is characterized. The gist of claims 6 and 7 can be added to the eighth aspect of the invention.

According to the invention described in claim 8, the computer is caused to output the predicted shape of the wire-like structure satisfying the predetermined condition by using the finite element method. In particular, while satisfying the shape characteristics, material characteristics and constraint conditions of the wire-like structure, the deformation state of the wire-like structure when this wire-like structure is displaced from the initial shape to the balanced final shape is finite. The calculation is performed sequentially using the element method, and the result is sequentially output.

According to the first, fifth, and eighth aspects of the present invention, a wire-like structure composed of a plurality of filaments is combined with an elastic body in which a plurality of beam elements having a circular cross section and linearity are maintained. Assuming, the predicted shape of the wire-like structure satisfying the predetermined condition is output using the finite element method. In particular, the appearance of the wire-like structure changing from the initial shape to the balanced final shape while satisfying the shape characteristics, material characteristics, and constraint conditions of the wire-like structure is sequentially evaluated using the finite element method. The calculation is performed and the result is sequentially output. Therefore, the state of the deformation of the wire-like structure until the wire-like structure is displaced to the final shape can be known before performing the assembling work. As a result, the optimum wiring design of the wire-like structure can be easily and accurately performed in a short period of time without depending on the skill of the designer.

According to the invention of claims 2 and 6, the state of deformation of the wire-like structure when a predetermined portion of the wire-like structure is displaced by applying a force is sequentially calculated, and the result is sequentially output. Therefore, it is possible to examine the state of deformation of the wire-like structure that accurately reflects the movement of the worker and the like expected at the time of assembly. In addition, it is possible to examine the state of deformation of the wire-like structure when a predetermined portion is arbitrarily pulled or bent.

According to the invention described in claim 3, the constraint condition is the coordinates of each vertex of the plurality of beam elements constituting the wire-like structure and the degree of freedom at each vertex, and the shape characteristic is the cross-sectional area of the beam element of the wire-like structure. The material properties are the second moment of area of the beam element, the second moment of area, the density, the modulus of longitudinal elasticity, and the modulus of transverse elasticity of the beam element. All of these values can be obtained in advance from the wire harness wired to the vehicle. Things. Therefore, the wiring simulation of the wire harness assuming the actual assembling work can be performed.

According to the fourth aspect of the invention, the state in which the target wire-like structure is deformed from the initial shape to the balanced final shape is sequentially calculated, and the result is sequentially output. Therefore, the state of the deformation of the wire-like structure until the wire-like structure is displaced to the final shape can be known before performing the assembling work. As a result, more optimal wiring design of the wire-like structure can be performed easily and accurately.

According to the seventh aspect of the invention, the output by the output means is temporarily stopped by the trigger based on the manual operation. Therefore, the user of the present apparatus can stop the output of the wire-like structure being deformed at an arbitrary point in time and examine the positional relationship and the degree of distortion between the wire-like structure and the interfering object.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, the overall shape of a wire harness as a wire-like structure to be designed and a typical support member will be described with reference to FIGS. FIG. 1 is a diagram schematically illustrating an overall shape of a wire harness to be designed in an embodiment of the present invention. FIG. 2 is a diagram illustrating a relationship between a representative support member that supports the wire harness and the degree of freedom of constraint. As will be described later, the present embodiment supports design by outputting a predicted shape to a wire harness as shown here by simulation.

As described above, connectors 2a, 2b, 2c, and 2d connected to electrical components (not shown) are attached to both ends of the wire harness 1 to be designed in the present embodiment, and various clips 3a, 3b, 3c and 3d are attached, and further, a branch point 4 is provided. Basically, each branch line of the wire harness 1 is different in the number and type of constituent wires, so that the thickness, length, elasticity, rigidity and the like of each branch line also differ.

(4) The connectors 2a, 2b, 2c, and 2d are detachably fixed at predetermined positions in accordance with the fixing position of the mating connector on the electrical component side and the mounting direction, and completely restrain the end of the wire harness. Further, the clips 3a, 3b, 3c, and 3d are completely or rotationally constrained at predetermined positions of a wire harness at predetermined positions such as a housing of electric components and stays.

Here, add a description about the clip. Basically, the clips include a long hole clip and a round hole clip. The round hole clip is also called a rotating clip, and includes a pedestal portion for holding a wire harness and support legs inserted into a round hole-shaped mounting hole provided on a stay or the like. The round hole clip is rotatable around the Z axis (vertical direction to the mounting site).

On the other hand, the long hole clip is also called a fixed clip, and includes a pedestal portion for holding a wire harness and support legs inserted into long hole-shaped mounting holes provided on a stay or the like. The cross-sectional shape of the support leg is an elongated hole substantially similar to the mounting hole. The long hole clip cannot rotate around the Z axis.

Furthermore, the long hole clip and the round hole clip include a corrugated long hole clip and a corrugated round hole clip that can rotate around the X axis (the longitudinal direction of the wire harness). FIG. 2 shows the degree of freedom of restraint in each axial direction and around each axis of such a clip.

In FIG. 2, the X axis, the Y axis, and the Z axis correspond to three orthogonal axes in the right-hand local coordinate system at each node (or node) on the wire harness. For example, the Z-axis is set to coincide with the clip axis, but these determination methods can be appropriately changed depending on the function to be used. In the drawing, the degree of freedom of constraint at the branch point is also shown for reference. Although not shown here, the nodes on the wire harness arbitrarily set other than the above-mentioned constraint points are basically completely free. As described later, such a constraint degree of freedom is set for each node before calculating the predicted path and the shape deformation.

Next, with reference to FIG. 3 to FIG. 6, the assumptions assumed in the present embodiment, the theory used, and the outline of the basic formula will be described. 3A is a diagram illustrating an appearance of the wire harness, FIG. 3B is a diagram illustrating a state where the wire harness of FIG. 3A is discretized, and FIG. FIG. 4 is a diagram illustrating the wire harness of FIG. 3A with beam elements and nodes. FIG. 4 is a diagram for explaining a degree of freedom in a wire harness represented by beam elements and nodes. FIG. 5 (A) is a diagram showing the wire harness represented by three beam elements, and FIG. 5 (B) is a diagram showing a state where the three beam elements of FIG. 5 (A) are connected. FIG. 6A is a diagram showing a state of measuring a second moment of area and a longitudinal elastic modulus, and FIG. 6B is a diagram showing a state of measuring a second moment of area and a longitudinal elastic coefficient. is there.

First, in the present embodiment, the following assumptions are made when the finite element method is used for designing a wire harness.
(1). It is assumed that the wire harness is an elastic body.
(2). Assume that the wire harness is a combination of beam elements.
(3). It is assumed that linearity is maintained for each beam element.
(4). Assume that the cross section of the wire harness is circular.
In the present embodiment, by making such an assumption, it becomes possible to apply the finite element method to the wire harness, which has not been made conventionally.

に お い て In the present embodiment, first, the wire harness is discretized. That is, as shown in FIG. 3A, the wire harness 1 in which the plurality of electric wires 11 are bundled by the protective member such as the tape 12 can be regarded as a continuous body. Next, as shown in FIG. 3B, such a wire harness 1 is divided (discretized) into several beam elements C1, C2, C3,. That is, since the wire harness is like a single rope, it can be considered that a finite number of beam elements are connected.

Therefore, as shown in FIG. 3C, the wire harness can be represented as a plurality of beam elements C1, C2, C3,... Connected by a plurality of nodes N1, N2, N3,. The characteristic values required for the beam elements are as follows.
Length 1 (see FIG. 3B)
Cross-sectional area A (see FIG. 3 (B))
Second moment of area I
Secondary moment of area J
Density ρ
Longitudinal elastic modulus E
Transverse elastic modulus G
As described later, in the present specification, the length 1 and the cross-sectional area A are defined as shape characteristics, and the second moment of area I, the second moment of cross-section J, the density ρ, the longitudinal elastic modulus E and the transverse elastic modulus G are defined as materials. Characteristics.

Then, as shown in FIG. 4, each beam element C (C1, C2, C3,...) Has two nodes α and β. In the three-dimensional space, the node α has three translation components and three rotation components, and thus has a total of six degrees of freedom. The same applies to the node β. Therefore, the beam element C has 12 degrees of freedom.

In the figure,
_Fxi : The force of the i-th element in the xi-axis direction _Fyi : The force of the i-th element in the yi-axis direction _Fzi : The force of the i-th element in the zi-axis direction _Mxi : The moment of the i-th element around the xi-axis _Myy : Moment of the i-th element around the yi axis M _zi : Moment of the i-th element around the zi-axis U _xi : Displacement of the i-th element in the xi-axis direction U _yi : Displacement of the i-th element in the yi-axis direction U _zi : i The displacement of the ith element in the zi-axis direction _θxi : The angular displacement of the ith element in the xi-axis direction _θyi : The angular displacement of the ith element in the yi-axis direction _θzi : The angular displacement of the ith element in the zi-axis direction α is the left side Is the node on the right, and β is the node on the right.

By the way, it is known that the displacement of a structure due to a non-vibrating static force satisfies Hook's law shown in the following equation (1) within an elastic range.
Kx = F (1)
Here, K: spring constant, x: displacement, and F: force.

Also, it is known that the Hook's law similarly holds for the beam element C shown in FIG. However, since the beam element C has 12 degrees of freedom as described above, as shown by the following equation (2), the relationship between force and displacement is determined by a matrix of 12 rows and 12 columns and a vector of 12 rows. Can be expressed.

Here, the matching condition and the balancing condition will be described. Here, for the sake of simplicity, as shown in FIG. 5A, the wire harness is represented by three beam elements C1, C2, and C3. In this case, the displacement of the node 1β of the beam element C1 and the displacement of the node 2α of the beam element C2 are equal, and the forces applied to both nodes are balanced. Similarly, the displacement of the node 2β of the beam element C2 and the displacement of the node 3α of the beam element C3 are also equal, and the forces applied to both nodes are balanced. Therefore, by satisfying the conditions of the continuity of the displacement and the balance of the force, the beam elements C1 and C2 and the beam elements C2 and C3 can be connected as shown in FIG.

In the figure,
_Fxi : The force of the i-th element in the xi-axis direction _Fyi : The force of the i-th element in the yi-axis direction _Fzi : The force of the i-th element in the zi-axis direction _Mxi : The moment of the i-th element around the xi-axis _Myy : Moment of the i-th element around the yi axis M _zi : Moment of the i-th element around the zi-axis U _xi : Displacement of the i-th element in the xi-axis direction U _yi : Displacement of the i-th element in the yi-axis direction U _zi : i zi-axis direction of displacement theta _xi turn elements: angular displacement xi-axis direction of i-th element theta _yi: yi-axis direction of the angular displacement theta _zi of the i-th element: indicates zi-axis direction of the angular displacement of the i-th element,
i = 1α, 1β, 2α, 2β, 3α, 3β.

Then, when the continuity of the displacement and the balance of the force in the beam elements C1, C2, and C3 shown in FIG. 5B are shown in the same form as the above equation (2), the following equation (3) is obtained. Become.

Here, the matrices M1, M2 and M3 of 12 rows and 12 columns in the equation (3) are the same as those shown in the above equation (2). However, the portions M12 and M23 where the matrices M1, M2 and M3 overlap are the sum of the components of each matrix.

Four or more beam elements can be handled similarly. In this way, a mathematical model of a wire harness divided into an arbitrary number of beam elements can be created.

Incidentally, when the above equation (3) is simply expressed,
[K] {x} = {F} ... (4)
It becomes.
Therefore, for example, if the force applied to the clip is determined in advance assuming that the clip is attached to each node, the path, that is, the wire harness is determined by calculating the displacement vector {x} based on the above equation (4). Can be calculated. Conversely, if the path is determined, the force vector {F} at each node can be calculated. Based on such a basic concept, in the present embodiment, the predicted route and the shape deformation of the wire harness are calculated. The unknowns in the displacement vector {x} and the force vector {F} can be obtained by using a known Newton-Raphson method, an arc length method, or the like.

The general matrix finite element method as described above is also shown in Non-Patent Document 1, for example.

Here, in the present embodiment, an example of a method of obtaining each characteristic value required for the beam element will be described below. First, the length l, the cross-sectional area A, and the density ρ can be obtained by a simple calculation after a target wire harness is created and measured using a caliper, a measure, a weighing scale, and the like.

In addition, when the measurement method shown in FIG. 6A is performed, the longitudinal elastic modulus E can be expressed by the following equation (5).
E = FL ³ / 3XI (5)
Further, since the wire harness is assumed to have a circular cross section as described above, the second moment of area I can be expressed by the following equation (6).
^{I = πD 4/64 ... (} 6)
Therefore,
E = 64FL ³ / 3XπD ⁴ (7)
It becomes.
In this measurement,
E = (F / X) × (64L ³ / 3πD ⁴ )
The relationship between F and x may be measured.

On the other hand, when the measurement method shown in FIG. 6B is performed, the transverse elastic coefficient G can be expressed by the following equation (8).
G = (TL / θJ) × 2 (8)
Since the wire harness is assumed to have a circular cross section, the secondary moment of area J can be expressed by the following equation (9).
^{J = πD 4/32 ... (} 9)
The twisting power is
T = FS ... (10)
It becomes.
Therefore,
G = (32FSL / θπD ⁴ ) × 2 = (F / θ) (32SL / πD ⁴ ) × 2 (11)
Therefore, the relationship between F and θ may be measured.

The above measurement method is an example, and each value may be obtained by a method other than the above measurement example. Alternatively, a typical wire harness may be measured in advance and stored in a database, and this may be used as appropriate.

Next, a description will be given of a hardware configuration according to the present embodiment, which calculates and outputs the shape of the wire harness according to the processing procedure described later using the above theory and basic formula. FIG. 7 is a block diagram showing a hardware configuration according to the present embodiment.

As shown in FIG. 7, in the present embodiment, for example, a personal computer is configured including a microcomputer 21, an input device 22, a display device 23, a printing device 24, a storage device 25, a communication interface 26, and a read / write device 27. A computer is used. The microcomputer 21 includes a CPU 21a (central processing unit), a ROM 21b for storing a boot program and the like, and a RAM 21c for temporarily storing various processing results. The input device 22 is a keyboard, a mouse, or the like for inputting the above values, the display device 23 is an LCD or a CRT for displaying the processing result, and the printing device 24 is a printer for printing the processing result.

The storage device 25 is a hard disk drive that stores the installed wiring design support program 29a and the processing results of the program 29a, and the communication interface 26 communicates with an external device using, for example, the Internet or a LAN line. It is a modem board or the like for performing data communication. The read / write device 27 reads a wiring design support program 29a (corresponding to claim 8) according to the present invention stored in a recording medium 29 such as a CD-ROM or a DVD-ROM. This is a device for writing the calculation result to the recording medium 29. These components are connected via an internal bus 28.

The microcomputer 21 installs the wiring design support program 29a read by the read / write device 27 in the storage device 25. When the power is turned on, the microcomputer 21 is started according to a boot program stored in the ROM 21b, and starts up the installed wiring design support program 29a. In accordance with the wiring design support program 29a, the microcomputer 21 performs processing related to the wiring design support of the present invention, causes the display device 23 or the printing device 24 to output the processing result, and stores the processing result in the storage device 25 or the recording device 25. For example, it is stored in the medium 29. The wiring design support program 29a can be installed in another personal computer or the like having the above-described basic configuration. After the installation, the computer is caused to function as a wiring design support device (corresponding to claims 5, 6, and 7). . Note that the wiring design support program 29a may be provided not only via the recording medium 29 but also via a communication line such as the Internet or a LAN.

処理 Furthermore, a processing procedure according to the present embodiment will be described with reference to FIGS. FIG. 8 is a flowchart illustrating a processing procedure according to the present embodiment performed using the hardware configuration illustrated in FIG. 7. FIGS. 9A to 9D are diagrams exemplifying output results in the process of each process shown in FIG.

First, based on the initial values set in step S1 shown in FIG. 8, an initial shape is calculated in step S2, and in step S3, the calculated initial shape 1a is output as shown in FIG. 9A. You. As an initial value for obtaining the initial shape 1a, for example, a position at which connectors at both ends (corresponding to the positions of nodes 1a1 and 1a8 in the drawing) of the target wire harness are used. The worker bends with normal force when assembling the wire harness or the minimum bending radius depending on the restraint direction, the coordinates and restraint direction of the clip attached to the middle part of this wire harness, or the material characteristics of this wire harness Alternatively, a bending radius or the like that can be used may be used. In any case, it is preferable to output an initial shape that reflects the shape of the target wire harness before assembly. The shape calculation process is performed by the microcomputer 21. The input device 22 is used for setting the initial value, and the display device 23 is used for outputting the initial shape. In the following processing, the shape calculation processing is also performed by the microcomputer 21, the input device 22 is used to set each value, and the display device 23 is used to output the calculation result.

Next, in step S4, the nodes 1a1 to 1a8 as shown in FIG. 9B are assigned to the output initial shape 1a, and a predetermined constraint condition at each of the nodes 1a1 to 1a8 is set. Is done. As the constraint conditions, the type of constraint (complete constraint, rotational constraint, complete freedom, etc.), local coordinates, and the like for each of the nodes 1a1 to 1a8 are set as shown in FIG. These constraint conditions correspond to the displacement destination. As each of the nodes 1a1 to 1a8, a portion to which a support member such as a connector or a clip is attached is assigned. In addition, as shown in FIG. 2, the names of the support members such as the connector and the fixing clip may be used for setting the type of constraint. Each value set here relates to each element in the displacement vector {x} in the above equation (3).

と 共 に At the same time, in step S4, the shape characteristics and material characteristics of the wire harness to be predicted are also set. The length l and the cross-sectional area A are set as the shape characteristics, and the second moment of area I, the second pole moment J, the density ρ, the modulus of longitudinal elasticity E, and the modulus of transverse elasticity G are set as the material properties. . For these, values measured or calculated in advance as described above are used. The value set here relates to each element in the rigidity matrix [K] in the above equation (3).

Further, in step S4, as shown in FIG. 9B, a force f to be applied to a predetermined portion of the wire harness, for example, a node 1a8 corresponding to a position where a connector is attached may be set. This force f is based on, for example, the movement of the worker expected at the time of assembly. The value set here relates to each element in the force vector [f] in the above equation (3). By setting the force f in this way, it is possible to study the state of deformation of the wire-like structure that accurately reflects the movement of the worker and the like expected at the time of assembly. In addition, it is possible to examine the state of deformation of the wire-like structure when a predetermined portion is arbitrarily pulled or bent. In step S4, various control values and the like related to the calculation process are also set. This step S4 corresponds to the setting means and the second setting means in the claims.

After the setting of each value necessary for the shape calculation is completed, if there is a predetermined trigger for starting the calculation, the initial shape 1a is erased from the display device 23 in step S5, and the process proceeds to step S7 and subsequent steps. . In step S7 and subsequent steps, the state of deformation until the initial shape of the wire harness is displaced to a balanced final shape that satisfies the set constraint conditions and the like is sequentially updated and output on the display device 23. This state corresponds to, for example, a plurality of time points t ₁ , t ₂ ,..., T _i assigned from the initial shape to the final shape. In addition, the time from the initial shape to the final shape is set to, for example, 10 seconds, and the state of the deformation every second is output. This processing will be described below.

First, after setting the time point t _i to the time point t ₁ in step S6, the process proceeds to step S7 and subsequent steps. Then, in the process loop of steps S7~ step S11, sequentially, the time t _1, t _2, ..., the shape of the wire harness is calculated using the finite element method in the t _i, the wire harness up to the time t _d The state of the deformation is updated and output.

That is, in step S7, the values required for the shape calculation set in step S4 are applied to the finite element method, in particular, the equation (3), to calculate the predicted shape at the time point t _i . Next, in step S8, the predicted shape (intermediate shape) at the time point t _i calculated in step S7 is output to the display device 23. After counting up the time point t _i in step S9, it is determined in step S11 whether the time point t _i has reached the final time point t _d . Step S7 corresponds to a calculating means in the claims.

Further, if it is determined in step S10 that the time point t _i has not yet reached the final time point t _d (N in step S10), the predicted shape at the time point t _i is deleted in step S11, and then the process proceeds to step S7. Returning, the predicted shape at the next time point t _i is calculated in the same manner as described above. That is, until the time point t _i reaches the final time point t _d , the calculation and output processing of the intermediate shape are repeated in steps S7 and S8. Through such processing, the state of deformation of the wire harness as shown in FIG. 9C is sequentially output. That is, the state of deformation from the initial shape 1a to the final shape 1d described later through the intermediate shapes 1b and 1c is output. In the figure, the positions of the nodes 1z1, 1z2, 1z3, 1z4, 1z5, 1z6, 1z7, and 1z8 of the final shape 1d are the nodes 1a1, 1a2, 1a3, 1a4, 1a5, 1a6, 1a7 in the initial shape 1a, respectively. , And 1a8. The nodes 1b8 and 1c8 of the intermediate shapes 1b and 1c correspond to the nodes 1a8 of the initial shape 1a.

According to the above processing, the intermediate shape at each time point is automatically and sequentially updated and output. However, the update output of step S11 is temporarily stopped between step S10 and step S11. May be inserted (corresponding to a temporary stop control means in the claims). That is, the current shape may be stopped and output on the display device 23 until a predetermined trigger by the input device 22 occurs. By doing so, the user of the present apparatus can stop the state of the wire harness during deformation at an arbitrary point in time and examine the positional relationship between the wire harness and the interfering object, the degree of distortion, and the like.

On the other hand, when it is determined in step S10 that the time point t _i has reached the final time point t _d (Y in step S10), the process proceeds to step S12, and the prediction at the final time point t _d as shown in FIG. After outputting the shape, that is, the final shape 1z, on the display device 23, a series of processing ends. This final shape 1z is a mechanically balanced and stable state that satisfies the set constraint conditions and the like. The final shape 1z may also be output to the printing device 24. Steps S8 and S12 correspond to output means in the claims.

As described above, according to the present embodiment, the state of deformation until the wire harness is displaced to the final shape can be known in advance before performing the assembling work. As a result, the optimum wiring design of the wire harness can be easily and accurately performed in a short period of time without depending on the skill of the designer. In particular, it is possible to apply the finite element method by considering the wire harness as an elastic body in which a plurality of beam elements that maintain linearity in a circular cross section are combined, thereby realizing more accurate shape prediction. .

The method and the device of the present invention are not limited to a wire harness wired in a vehicle, but can be similarly applied to a wire-like structure wired indoors.

It is a figure showing roughly the whole shape of the wire harness used as a design object in an embodiment of the present invention. It is a figure showing the relation between the typical support member which supports a wire harness, and the degree of freedom of restraint. 3A is a diagram illustrating an appearance of the wire harness, FIG. 3B is a diagram illustrating a state where the wire harness of FIG. 3A is discretized, and FIG. FIG. 4 is a diagram illustrating the wire harness of FIG. 3A with beam elements and nodes. It is a figure for explaining a degree of freedom in a wire harness represented by a beam element and a node. FIG. 5 (A) is a diagram showing the wire harness represented by three beam elements, and FIG. 5 (B) is a diagram showing a state where the three beam elements of FIG. 5 (A) are connected. FIG. 6A is a diagram showing a state of measuring a second moment of area and a longitudinal elastic modulus, and FIG. 6B is a diagram showing a state of measuring a second moment of area and a longitudinal elastic coefficient. FIG. 2 is a block diagram illustrating an example of a hardware configuration according to the embodiment. 5 is a flowchart illustrating a processing procedure according to the embodiment. FIGS. 9A to 9D are diagrams exemplifying output results in the process of each process shown in FIG.

Explanation of reference numerals

1 wire harness (wire-like structure)
2a, 2b, 2c, 2d connector 3a, 3b, 3c, 3d clip 4 branch point 21 microcomputer 22 input device 23 output device 24 printing device 25 storage device 26 communication interface 27 read / write device 28 internal bus C1-C7 beam element N1 To N8 node

Claims (8)

A wire-like structure composed of a plurality of filaments is regarded as an elastic body in which a plurality of beam elements having linear cross-sections are maintained, and a predetermined condition is satisfied using a finite element method. By predicting and outputting the shape of the wire-like structure, a method for supporting an optimal wiring design of the wire-like structure,
Applying information on the shape characteristics, material properties, and constraint conditions of the wire-like structure as the predetermined condition to the finite element method so that the wire-like structure satisfies the predetermined condition from an arbitrary initial shape. The state of deformation to the final shape that has been removed is sequentially calculated, and the result is sequentially output,
A wiring design support method for a wire-like structure. The wiring design support method for a wire-like structure according to claim 1,
A state of deformation of the wire-like structure when a predetermined force is applied to a predetermined portion of the wire-like structure and displaced is sequentially calculated and the result is sequentially output.
A pre-wiring design support method for a wire-like structure, characterized in that: The wiring design support method for a wire-like structure according to claim 1 or 2,
The wire-like structure is a wire harness wired to a vehicle,
The constraint condition is a coordinate of each vertex of the plurality of beam elements and a degree of freedom at each vertex,
The shape characteristics are the cross-sectional area and length of the beam element of the wire-like structure; and
The material properties are a second moment of area, a second moment of area, a density, a modulus of longitudinal elasticity, and a modulus of transverse elasticity of the beam element.
A wiring design support method for a wire-like structure. In a method for supporting an optimal wiring design of a wire-like structure by calculating a predicted shape regarding the wiring of the wire-like structure composed of a plurality of linear materials,
Sequentially calculating the state in which the target wire-like structure is deformed from an arbitrary initial shape to a balanced final shape, and sequentially outputting the result,
A wiring design support method for a wire-like structure. A wire-like structure composed of a plurality of filaments is regarded as an elastic body in which a plurality of beam elements having linear cross-sections are maintained, and a predetermined condition is satisfied using a finite element method. By predicting and outputting the shape of the wire-like structure, a device that supports optimal wiring design of the wire-like structure,
Setting means for setting information on the shape characteristics, material characteristics and constraint conditions of the wire-like structure as the predetermined condition,
Calculation means for applying the predetermined condition to the finite element method and sequentially calculating a state in which the wire-like structure is deformed from an arbitrary initial shape to a balanced final shape satisfying the predetermined condition. When,
Output means for sequentially updating and outputting the state of deformation of the wire-like structure based on the calculation result by the calculation means,
A wiring design support device for a wire-like structure, comprising: The wiring design support device for a wire-like structure according to claim 5,
The predetermined condition further includes a second setting means for setting a force to be applied to a predetermined portion of the wire-like structure,
The calculating means sequentially calculates the state of deformation of the wire-like structure when the force is applied and displaced,
A wiring design support device for a wire-like structure. The wiring design support device for a wire-like structure according to claim 5,
Pause control means for temporarily stopping the output by the output means by a trigger based on a manual operation,
A wiring design support device for a wire-like structure, further comprising: A wire-like structure composed of a plurality of filaments is regarded as an elastic body in which a plurality of beam elements having linear cross-sections are maintained, and a predetermined condition is satisfied using a finite element method. By predicting and outputting the shape of the wire-like structure, in order to support the optimal wiring design of the wire-like structure, a computer,
Setting means for setting information on the shape characteristics, material characteristics and constraint conditions of the wire-like structure as the predetermined condition,
Calculation means for applying the predetermined condition to the finite element method and sequentially calculating a state in which the wire-like structure is deformed from an arbitrary initial shape to a balanced final shape satisfying the predetermined condition. ,
Based on the calculation result by the calculation unit, the state of the deformation of the wire-like structure is sequentially, functioning as an output unit that updates and outputs,
A wiring design support program for wire-like structures.

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