JP6614649B2 - Design and production system - Google Patents

Description

  The present invention relates to a design and production system of a product such as a structural member, and more particularly to bioinnovative design in which data obtained from a biological form is incorporated into a design technique.

It is pointed out that it is important to apply these shapes, forms, etc. to products such as structural members because living organisms have adaptability, adaptability, and learning ability to various environments. However, no specific application to mechanical design has been proposed so far.
Conventionally, “bio-inspired design” has been proposed as a design method created from similar ecosystems.
This was often a material design or a robot movement, and it was close to “ecosystem imitation”.
Bioinnovative design, on the other hand, does not simply imitate ecosystems, but rather uses them to break through conventional design technologies to solve the conflicting relationship between weight reduction and strength.・ Provide innovative design methods to be developed.
The present inventors studied to obtain new artifacts by evolving information obtained from ecosystems.
In the field of mechanical parts such as structural members and vehicle parts, weight reduction, high strength, and the like are required as countermeasures for reducing the environmental load.
As one of means for achieving the light weight and high strength, FRP (fiber reinforced resin) has attracted attention.
Therefore, the present inventors examined FRP using a braid technique that facilitates production of a structural member having a complicated shape as a realization of bioinnovative design that effectively utilizes data obtained from biological forms as design information.

  Patent Document 1 discloses a braided structure in which a braid composed of a braider having a mandrel or the like and a resin are combined, but is not based on biological form information.

Japanese Patent Laid-Open No. 7-126968

It is an object of the present invention to provide a design / production system comprising a bioinnovative design based on a combination of biological form information and an optimal design method using machine learning.
Furthermore, the purpose is to provide a design / production system that combines biomorphology information and braid technology.

  The design / production system according to the present invention includes a biomorphology database obtained from a biomorphism such as an animal skeleton system and a branch network of plants, and a design database obtained by quantifying or modeling the biomorphology data. The product is manufactured on the basis of the optimum design means utilizing the design database and the information obtained by the optimum design means.

Here, the biological morphology database stores data obtained by modeling a three-dimensional morphology such as an animal skeleton, a branch network of plants, a development mechanism, and the like based on a CT image or the like.
Although the biomorphological database provides visual ideas to designers, there are many cases where loads and boundary conditions are not clear as they are.
Therefore, the present invention provides a design database in which individual data obtained from a biological form is combined to store numerically or modeled data.
Thereby, using this design database, for example, an optimal design for the purpose of weight reduction and high strength can be performed using an optimal design method using machine learning such as a “Radial Basis Function” network.
In this case, the information obtained by the optimum design means is preferably fed back to the design database.
Thereby, virtual data obtained by searching for the optimum solution can be added to and updated in the design database.

The shape and structure of the product obtained as described above are evolved forms unique to living things, and often have complicated shapes.
Therefore, the present invention preferably applies braid technology to the manufacture of products.
Braided technology can supply fiber yarns wound around multiple bobbins while crossing them on a mandrel to form a braided structure directly. Strength, elastic modulus, etc. can be adjusted by adjusting the orientation angle of the yarn and inserting neutral yarn. Is easy to control.
The braid is more advantageous in terms of cost, production time, and strength than a knitted fabric requiring warp preparation and a knitted fabric whose basic unit is a loop.
Thereby, a product can be made to be the fiber reinforced resin member using the reinforced fiber preform which consists of a braid structure.
Further, according to the braided technology, the fiber reinforced resin member can be composed of a shell portion having a hollow cross-sectional shape and a rib portion formed inside the shell portion.
Further, the fiber reinforced resin member may be a reinforced fiber preform in which a fiber layer having a braided structure is formed in a bundle.
Thereby, it is possible to cope with a complicated structure or shape corresponding to the bone density distribution or the like of the bone.

The design / production system according to the present invention can make effective use of biomorphological information for product design, and can contribute to light weight and high strength product design.
Further, by integrating the braid technology, an FRP member excellent in light weight and high strength can be obtained.
As the FRP member, glass fiber may be used as the reinforcing fiber, but a CFRP member using carbon fiber as the reinforcing fiber is preferable.

An example of the database of a biological form is shown. An example of a digitized design database is shown. An example of a design database converted into an analysis model is shown. An example of a Pareto analysis front optimized by design database is shown. An example of the flow of manufacturing a fiber preform based on the optimum design is shown. The simulation analysis conditions based on the optimal design are shown. The analysis result by the analysis conditions shown in FIG. 6 is shown. An example of manufacturing a braid is shown. An example of spindle arrangement and moving structure when manufacturing a fiber preform having a shell + rib structure is shown. An example of a shell + rib type product is shown. An example of spindle arrangement and moving structure when manufacturing a fiber preform having a shell + rib structure is shown. An example of spindle arrangement and moving structure in the case of manufacturing a fiber preform composed of a plurality of fiber layers having a bundle between layers is shown. The simulation analysis conditions using a braided-structure shell element (PART COMPOSITE fully integrated shell element) are shown. The analysis result by the analysis conditions shown in FIG. 13 is shown.

  Hereinafter, although the structural example of the design and production system which concerns on this invention is demonstrated based on figures, this invention is not limited to this.

FIG. 1 shows a part of a biomorphological database obtained by CT modeling an animal skeleton using a three-dimensional morphological modeling technique based on CT images.
An example of a design database quantified as an index based on this biological morphology database is shown in FIG.
An example of an analysis model design database is shown in FIG.
FIG. 4 shows an example of a Pareto front obtained by an optimal design method based on machine learning using RBF (Radial Basis Function) based on these databases.
In this way, an improved Pareto front was obtained based on the biomorphological database.
The solution obtained by the optimum design is fed back as a virtual database as shown in FIG.

FIG. 5 shows a process for manufacturing a mandrel using a 3D printer based on the design information obtained by the optimum design, performing braiding using the braid machine, and manufacturing the mandrel into a carbon fiber preform.
A CFRP member is obtained by RTM molding (Resin Transfer Molding) in which a carbon fiber preform is sealed in a mold and resin is injected.
In this case, the VaRTM method in which the inside of the mold is evacuated can also be used.

Next, the effect of the optimized shape was verified by simulation, and will be described below.
The study conditions were a prism model and a comparative reference model.
Analysis conditions are shown in FIG.
A bending load and a compressive load were applied to the four-point fixation, and the maximum equivalent stress was compared.
The analysis result is shown in FIG.
As a result, the usefulness of the optimal design method using machine learning was verified.

Next, an example of manufacturing a fiber preform by braid technology will be described.
As shown in FIG. 8, a braid is obtained by moving along the circumference while the outer and inner spindles having bobbins wound with fiber yarns are alternately switched.
In addition, when the movement path (a to d) of the spindle is designed as shown in FIG. 9, ribs are formed between the inner layer / outer layer braid structure, and if a more complicated path is moved, the outer path as shown in FIG. It is possible to manufacture a fiber preform having a hollow cross section composed of a shell portion 1 that forms a radial shape and a rib portion 2 that is formed so as to connect the inside thereof.
This makes it possible to manufacture complex products that reflect bone density.
An example of spindle arrangement and moving structure in this case is shown in FIG.
The bobbin (spindle) is moved by four types of paths a to d, and the core is arranged between the braid layers to form a shell-rib structure.
Further, if the four types of paths a to d as shown in FIG. 12 are set, a reinforced fiber preform composed of a multi-layer fiber layer in which two layers of the outer layer and the inner layer are bound can be obtained.

Next, the analysis of the braid structure and the results will be described.
FIG. 13 shows simulation analysis conditions using shell elements (fully integrated shell elements).
FIG. 13A shows the analysis results when the plate thickness and material constant are set for each layer.
FIGS. 13B and 13C model the case where the rigid layers are scattered in the soft layer, and are assumed as follows according to the scattered ratio of the rigid layers.
<0%>: A model in which sheets are simply laminated by resin bonding is assumed.
<25%>: Assuming a model having bonded portions of reinforcing fibers between layers at a ratio of 25%.
<50%>: Assuming a model having a bonded portion of reinforcing fibers between layers at a ratio of 50%.
The analysis result is shown in FIG.
In contrast to the “Mieses equivalent stress maximum value of 9.6 MPa” in which “the sheet is simply laminated by resin bonding” <0%>, the <25%> and <50%> models have values of 8.1 MPa and 7.MPa, respectively. An increase in strength of 9 MPa and about 16 to 18% was observed.
For these reasons, when the design / production system according to the present invention is used, it is possible to reduce the strength and weight more than the form of the ecosystem based on the biological form information.

1 Shell part 2 Rib part

Claims (1)

A biomorphological database that models three-dimensional shapes obtained from biological forms such as animal skeletal systems and branched networks of plants;
A design database that digitizes or / and models the biomorphological data,
Production means for producing a mandrel for use in a braided machine by an optimum design method using machine learning utilizing the design database ;
Means for producing a reinforcing fiber preform having a braid structure produced by a braid machine using the mandrel produced as described above;
And a means for producing a fiber reinforced resin member using the reinforced fiber preform produced as described above .