JPH09245072A - Structure design system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure design system for deciding the structure of standard components for constituting a structure and a tightening method. SOLUTION: This structure design system using a computer is provided with an evaluation model input means 2 for inputting one or plural evaluation models composed of the shape model of the structure, analysis conditions and an analysis model, a design specification input means 7 for inputting design specifications composed of a design variable, the constraint of the design variable, an evaluation item and the allowable value of the evaluation item and a structure improving means 12 for obtaining the evaluation values of the respective evaluation items for the respective evaluation models, changing the design variable of the evaluation model by the evaluated result and generating one or plural new evaluation models. In the process of generating a new structure by the repetitive processing of the structure improving means 12, by utilizing the evaluation model input means 2 and the design specification input means 7 and changing the evaluation model, the design specifications and a structure improving method, a structure improving processing is controlled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure design system for determining a structure of standard parts constituting a structure and a fastening method.

[0002]

2. Description of the Related Art In a conventional structural design system, an analytical model and design specifications (design variables and their constraint conditions, evaluation items and their allowable ranges) for a predetermined initial structure are set.
Is set and the evaluation value of each evaluation item for the model is obtained. When this evaluation value is not within the set allowable range, structural design is performed by changing the design variables within the constraint conditions until the evaluation value falls within the allowable range. A publicly known example of such a structural design system is discussed in JP-A-3-224063. As a method of changing the design variable, there is a method using sensitivity analysis, which is discussed in Japanese Patent Laid-Open No. 160248/1994.

[0003]

In the prior art, a plurality of standard parts are combined and fastened (welding, rivets, bolts,
In the case where the structure of standard parts and the fastening method (fastening type, position and dimension) are targeted for the design of a structure such as a screw, there are the following problems.

(1) Since the user uses the data modeled by the solid, shell, beam or spring element, etc., for the fastening portion composed of welding, rivets, bolts, screws, etc., the actual design is performed directly from the model. Required fastening method
It is difficult to determine (fastening type, position, dimensions).

(2) In the structure improvement using the sensitivity analysis, the accuracy of the sensitivity analysis deteriorates when the dimension takes discrete values or the structure changes greatly, and the optimum solution is searched only from the local viewpoint. There are things you can't do. Also, if the evaluation method is unclear, sensitivity analysis cannot be applied.

(3) In the case of a design having many design variables and evaluation items, there are multiple combinations of design variables and evaluation methods of evaluation items, so the system automatically determines one solution according to one method. This means that it is impossible to consider the design based on the combination of other design variables and the evaluation method of the evaluation item.

A first object of the present invention is that when a user creates a model of a fastening portion, the user inputs data on the type, position and dimensions of the fastening necessary for actual design, and further analyzes the data. It is to provide a structural design system that automatically generates necessary analysis model data.

A second object of the present invention is to select one or a plurality of evaluation models, exchange some design variables between the plurality of evaluation models, and replace some design variables of another evaluation model with another. It is to provide a structural design system that generates a new evaluation model by changing the value.

A third object of the present invention is to generate a new evaluation model by a combination of various design variables and an evaluation method of various evaluation items while holding a plurality of evaluation models, and to construct a new structure and improve the structure. The purpose of the present invention is to provide a structural design system that supports the user's design work by showing the evaluation results of the method and structural improvement.

[0010]

In order to achieve the above-mentioned object, the present invention is a structural design system using a computer. In a structural design system, standard part input means for taking out and arranging standard parts from a standard part database and fastening between standard parts. Fastening member input means for inputting a fastening member to a part, analysis condition input means for inputting analysis conditions such as restraints and loads, analysis model generation means for designing a fastening member modeling and finite element division, design variables, Design condition input means for inputting constraint conditions of design variables, evaluation items and allowable values of evaluation items, design policy input means for inputting priority and weight for comprehensive evaluation of a plurality of evaluation items, evaluation value of each evaluation item And an evaluation value calculation means for calculating an overall evaluation value, an evaluation result output means for displaying evaluation results for each evaluation model in a table, a graph and a figure, an evaluation The evaluation models are grouped according to the level of each, and structural evaluation means for finding common points and differences between the design variables in the evaluation models in the same group and the evaluation models between different groups. Change means for changing the evaluation model by exchanging some design variables between the evaluation models or changing some design variables of the evaluation model to different values, and a structure for controlling repetitive process of structure improvement An improvement control means, standard parts, an evaluation model, a design specification, an evaluation value, and a data storage means for storing history data of structure improvement are provided.

Each means for achieving the above object operates as follows. The standard parts input means extracts standard parts from the standard parts database and arranges them. The fastening member input means inputs the fastening member to the fastening portion between the standard parts. The analysis condition input means inputs analysis conditions such as constraints and loads. The analytical model generating means models the fastening member and generates an analytical model by finite element division. The design specification input means inputs design variables, constraints, evaluation items, and allowable values. The design policy input means inputs the priority and weight for each evaluation item. The evaluation value calculation means is
Calculate the evaluation value and overall evaluation value of each evaluation item. The evaluation result output means displays the evaluation result for each evaluation model in a table, a graph and a diagram. The structure evaluation means groups evaluation models by evaluation level and finds common points and differences between the design variables in the evaluation models in the same group and the evaluation models between different groups. The structure modification means evaluates by selecting one or more evaluation models and exchanging some design variables between the evaluation models or changing some design variables of the evaluation models to different values. Change the model. The structure improvement control means controls the design policy input means, the evaluation value calculation means, the evaluation result output means, the structure evaluation means, and the structure modification means, and repeatedly executes the structure improvement. The data storage means stores standard parts, evaluation models, design specifications, evaluation values, and structural improvement history data.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present embodiment will be described below with reference to the drawings.

FIG. 1 shows an overall configuration diagram for realizing the present invention. 1 is an input / output device for inputting / outputting various data, 2
Is an evaluation model input unit for inputting a structural design evaluation model by a standard component input unit 3, a fastening member input unit 4, an analysis condition input unit 5, and an analysis model generation unit 6, and 7 is a design variable input unit 8, a constraint condition input unit. 9, a design specification input unit for inputting design specifications by the evaluation item input unit 10 and the allowable value input unit 11, 12 is a design policy input unit 13, an evaluation value calculation unit 14, an evaluation result output unit 15, a structure evaluation unit 16, a structure A structure improving unit that improves the structure of the evaluation model by the changing unit 17 and the structure improvement control unit 18, and 19 is a standard parts storage unit 20, an evaluation model group storage unit 21, a design specification storage unit 22, and an evaluation value storage unit 2.
3 and the structure improvement storage unit 24 show a data storage unit for storing various data.

The user activates 2, 7 and 12 using 1 to design the structure. 2, 7 and 12 operate independently of each other, and transfer data via 19. Hereinafter, the details of 2, 7, and 12 will be described in order.

In 2, the evaluation model including the shape model and the analysis model of the structure is created using 3 to 6. That is, in 3, the standard parts stored in 20 are taken out and placed on the work screen of 1. In 4, the fastening member is input to the fastening portion between the parts arranged in 3. Fastening members include continuous welding, intermittent welding, spot welding, rivets, bolts,
There are screws, etc., which can be set by inputting the data shown in FIG. As a result, the model of the fastening portion can be created by inputting according to the instruction of the fastening method in the drawing without requiring the know-how of a special modeling method for analysis. In 5, the analysis conditions such as constraints and loads are input to the shape model of the structure input in 3 and 4. In 6, 3
The fastening member is modeled by a solid, shell, beam or the like with respect to the shape model of the structure input in 5 to 5 (for example, there is a method shown in FIG. 3), and an analytical model such as a finite element model is generated. The shape model and the analysis model created in 2 are stored in 21 as one evaluation model.

At 7, the design specifications are input using 8-11. That is, in 8, the design variables, which are parameters that can be changed by the structural improvement in 12, are input from the evaluation model of the structure input in 2 and the standard parts stored in 20. In 9, the constraint condition is input within the range of the upper and lower limit values of the standard component stored in 20 for the design variable input in 8. At 10, various evaluation items such as displacement, stress, structural analysis value such as eigenvalue, cost, mass, tipping property, productivity, and assembly property are input. In 11, the allowable values such as the allowable range, maximization, and minimization are input for the evaluation item input in 10. The design specification set in 7 is stored in 22.

At 12, the structure is improved based on the evaluation model stored at 21 and the design specifications stored at 22. That is, in 13, in order to comprehensively evaluate a plurality of evaluation items stored in 22, the design priority such as evaluation priority and weighting for each evaluation item is input. 14
Then, for the evaluation model stored in 21,
Then, the evaluation value of the evaluation item stored in and the total evaluation value according to the design policy set in 13 are calculated. The evaluation value and the comprehensive evaluation value obtained in 14 are stored in 23. In 15,
Using the evaluation model stored in 21, the design specification stored in 22, and the evaluation value stored in 23, a table and a graph of evaluation values for the design variables of each evaluation model, a diagram of the evaluation model and analysis results Are displayed on the work screen of 1. In 16, the evaluation models are grouped according to the level of the evaluation value for each evaluation model obtained in 14, and the common points and differences of the design variables are found in the evaluation models in the same group and the evaluation models between different groups. The common points and differences of the design variables found in 16 are considered as parameters that characterize the evaluation value, and are stored in 24. At 17, one or more evaluation models are selected from the evaluation models stored at 21, and some design variables are exchanged between the plurality of evaluation models, or some design variables of the evaluation model are separated. A new evaluation model is generated by changing the value of. Selection of the evaluation model includes selection based on the evaluation value calculated in 14 or the total evaluation value, random selection,
There are selections by the structure improvement rules stored in 24, and changes in the design variables include changes in common points or differences by 16, random changes, changes by the structure improvement rules stored in 24, and the like. Also, the new evaluation model generated in 17 is stored in 21. In 18,
13-1 again including the new evaluation model added to 21
The process of repeating the structure improvement of 7 is controlled. The history of the evaluation model and the evaluation value by the structural improvement is stored in 24 as a structural improvement rule and is used in 17 structural improvement.

A reference numeral 12 repeats the structure improving process until the end condition of the user is satisfied. By repeating this structure improvement processing, the evaluation model having a high total evaluation value set in 13 gradually increases in 21. The user can select the required structure while viewing the structure of the new structure displayed in 1, the structure improvement method, and the evaluation result. Further, during the structure improvement process, the data of the standard parts, the evaluation model and the design specification can be added / corrected / deleted by 2 and 7, and the parameters of the design policy and the structure changing method can be tuned by 13, 16 and 17. .

Details of 12 will be described by taking as an example the design of a method for reinforcing and fastening the sheet metal housing.

FIG. 4 is a schematic view of a target sheet metal housing structure. The housing is configured by combining and fastening a floor plate, a side plate, a ceiling plate, and a reinforcing material stored in the standard component storage unit 20.

FIG. 5 shows three types of evaluation models stored in 21. Here, focusing on the side plates of the sheet metal housing, the housings having different types of reinforcing materials and fastening methods on the side plates are registered.

FIG. 6 shows the design variables stored in 22.
The design variables are the thickness 601 of the side plate, the cross section 602 of the reinforcing material 1 having the cross-sectional shape and the cross-sectional dimension, the fastening 603 of the reinforcing material 1 having the type, position and size of the fastening, and the reinforcing material 2 having the cross-sectional shape and the cross-sectional dimension. The cross-section 604 and the fastening 605 of the reinforcing member 2 including the type, position and size of fastening were set.

FIG. 7 shows the constraint conditions of the side plate thickness input in 601. The constraint condition of the side plate thickness is defined by the standard component storage unit 20.
It was set to select from the standard dimensions of the five types of plate thickness stored in.

FIG. 8 shows the constraint conditions of the cross section of the reinforcing material input to 602 and 604. The restriction conditions of the cross sections of the reinforcing material 1 and the reinforcing material 2 are the same, and the setting is made so that the standard shape and the cross-sectional dimension stored in the standard component storage section 20 are selected.

FIG. 9 shows the constraint conditions for fastening the reinforcing material input to 603 and 605. The constraint conditions for fastening the reinforcing material 1 and the reinforcing material 2 are the same, and are set to be selected from the fastening type and size of the standard stored in the standard component storage unit 20.

FIG. 10 shows evaluation items and allowable values stored in 22. The evaluation item and the allowable value are set such that the displacement when the floor plate is fixed and a lateral load is applied to the side plate is within 3 mm 1001, the mass is minimized 1002, and the cost is minimized 1003.

FIG. 11 shows a table in which 15 is output to 1. Reference numeral 1101 is the design variable name shown in FIG. 6, 1102 is the changeable range of the constraint condition for each design variable shown in FIGS. 7 to 9, 1103 is the value of the design variable for each evaluation model, 1104 is shown in FIG. The evaluation item name shown, 1105 is the allowable value of the evaluation item shown in FIG. 10, 1106 is the priority of each evaluation item input at 13, 1107 is the weight value of each evaluation item input at 13, and 1108 is 14 The evaluation value of the evaluation item for each evaluation model obtained in step 3 is output. The data of 1103 and 1108 are 1106-111.
It is displayed in the order of the total evaluation value obtained from 14 from the data of 08. That is, first, focusing on displacements having a priority of 1106, the evaluation models are rearranged in ascending order of displacement, and if there are evaluation models with the same displacement, 1106
Are sorted in ascending order of the mass and cost values of which the priority order is 2. Here, the mass and the cost are "0.0, 1.
The value normalized by “0” is used to determine the magnitude by the value obtained by multiplying each evaluation value by the weight of 1107.

FIG. 12 shows a table to which a new evaluation model is added. The new evaluation model selects one or more rows in the table (selection of evaluation model), exchanges some columns of the selected rows (exchanges design variables), and changes some columns. It is generated by performing (changing design variables). Here, using the table of FIG. 11, the plate thicknesses of the evaluation model 4 and the evaluation model 5 in which the cross sections of the reinforcing material 1 of the evaluation model 2 and the evaluation model 3 of high overall evaluation are exchanged are shown. The evaluation model 6 and the evaluation model 7 randomly selected from the plate thickness constraint conditions of 7 and the fastening of the reinforcing material 2 of the high cost evaluation model 2 are changed to the fastening of the reinforcing material 2 of the low cost evaluation model 3. Evaluation model 8
Was added.

FIG. 13 shows the structure improvement rules stored in 24. The structure improvement rule is obtained from the five types of evaluation models generated by 17 and the evaluation value obtained by 14. These rules are used for selecting 17 evaluation models and changing design variables.

FIG. 14 is a graph of the evaluation value of the evaluation item for the design variable of each evaluation model output on the work screen 15 of 1.

FIG. 15 is a schematic view of the side plate of the evaluation model newly stored in 21 by 17.

From the table of FIG. 11 or FIG. 12, the graph of FIG. 14 and the diagram of FIG. 15, it is possible to know the influence of the evaluation value on the structure of the new structure, the structure improving method and the design variable.

[0033]

As the model of the fastening portion, it is sufficient to input the data of the type, position and dimension of the fastening necessary for the actual design, so that the know-how of the special modeling method for the analysis is not required, and the drawing It can be created by inputting according to the instructions of the fastening method. Further, the data of the fastening portion obtained by the structural improvement can be directly used for the actual design.

In the generation of a new evaluation model, the number of evaluation models with high evaluation is increased by taking in the constituent elements of the evaluation model having excellent evaluation results, or by taking in the improvement elements more effective than the past structural improvement results, and randomly. We are increasing the number of valuation models that incorporate new components through selection or random changes.

Even if the user adds / modifies / deletes the evaluation model and changes the evaluation method during the structure improvement process, the structure is changed according to the specified conditions. Therefore, various combinations of design variables and various evaluation methods are used. Can propose a new structure.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an embodiment of the present invention.

FIG. 2 is an explanatory diagram of one embodiment of the present invention.

FIG. 3 is an explanatory diagram of one embodiment of the present invention.

FIG. 4 is an explanatory diagram of one embodiment of the present invention.

FIG. 5 is an explanatory diagram of one embodiment of the present invention.

FIG. 6 is an explanatory diagram of one embodiment of the present invention.

FIG. 7 is an explanatory diagram of one embodiment of the present invention.

FIG. 8 is an explanatory diagram of one embodiment of the present invention.

FIG. 9 is an explanatory diagram of an embodiment of the present invention.

FIG. 10 is an explanatory diagram of an embodiment of the present invention.

FIG. 11 is an explanatory diagram of an embodiment of the present invention.

FIG. 12 is an explanatory diagram of an embodiment of the present invention.

FIG. 13 is an explanatory diagram of an embodiment of the present invention.

FIG. 14 is an explanatory diagram of an embodiment of the present invention.

FIG. 15 is an explanatory diagram of an embodiment of the present invention.

[Explanation of symbols]

1 ... I / O device, 2 ... Evaluation model input unit, 3 ... Standard component input unit, 4 ... Fastening member input unit, 5 ... Analysis condition input unit, 6
... analysis model generation unit, 7 ... design specification input unit, 8 ... design variable input unit, 9 ... constraint condition input unit, 10 ... evaluation item input unit, 11 ... allowable value input unit, 12 ... structure improvement unit, 13 ... design Policy input unit, 14 ... Evaluation value calculation unit, 15 ... Evaluation result output unit, 16 ... Structure evaluation unit, 17 ... Structure change unit, 18 ... Structure improvement control unit, 19 ... Various data storage unit, 20 ... Standard component storage unit , 21 ... Evaluation model group storage unit, 22 ... Design specification storage unit, 23 ... Evaluation value storage unit, 24 ... Structure improvement storage unit.

Claims (4)

[Claims] 1. In a structural design system using a computer, an evaluation model input means for inputting one or a plurality of evaluation models consisting of a shape model of a structure, analysis conditions and analysis models, and design variables and constraints of design variables. Design specification input means for inputting design specifications consisting of conditions, evaluation items, and allowable values of evaluation items, and evaluation values of each evaluation item for each evaluation model are obtained. Structure improving means for generating one or a plurality of different evaluation models, and the evaluation model inputting means, the design specification inputting means, and the structure improving means in the process of generating a new structure by repeating the structure improving means. Then, the structure improvement control means for controlling the structure improvement processing and various data are stored by changing the evaluation model, the design specification and the structure improvement method. Structural design system, comprising the chromatography data storage means. 2. The evaluation model input means according to claim 1, wherein the shape data of the fastening portion is created by inputting the fastening member between the parts constituting the structure, the fastening member is modeled, and the finite element division is performed. Structural design system that generates an analytical model by. 3. The structure improving means according to claim 1,
A structural design system that groups evaluation models according to the evaluation value level from each evaluation model and finds common points and differences of design variables in the evaluation model in the same group and the evaluation model between different groups. 4. The structure improving means according to claim 1,
A structure that changes the evaluation model by selecting one or more evaluation models and exchanging some design variables between the evaluation models or changing some design variables of the evaluation model to different values. Design system.