WO2003082550A2

WO2003082550A2 - Method and device for manufacturing fabric material

Info

Publication number: WO2003082550A2
Application number: PCT/BE2003/000052
Authority: WO
Inventors: Janne Kyttanen; Jiri Evenhuis
Original assignee: Materialise, Naamloze Vennootschap
Priority date: 2002-03-28
Filing date: 2003-03-25
Publication date: 2003-10-09
Also published as: AU2003218534A1; WO2003082550A3; BE1014732A3

Abstract

The present invention concerns a method for manufacturing fabric material. A digital description of the surface of the fabric material is designed in a first step by means of a computer; a textile pattern is projected onto this surface in a second step, so that a three-dimensional computer model is obtained, and the fabric material is manufactured on the basis of this computer model by means of Rapid Prototyping in a subsequent step.

Description

Method and device for manufacturing fabric material.

The present invention concerns a method for manufacturing fabric material.

For centuries, fabrics are made by weaving threads into one another according to different patterns. These fabrics are two-dimensional. Objects made of textile, in particular three-dimensional objects such as garments, are made on the basis of these two-dimensional fabrics by means of cutting and sewing. All this is time-consuming and usually requires expensive machinery.

Robots are known which can weave fabrics out of glass fibres around a three-dimensional model, but these fabrics are impregnated or coated with a resin. These robots are expensive, and every other shape requires another model.

Another technique for manufacturing fabric material is by means of knitting. Also for knitting, relatively expensive machines are used. Here, it is also known to knit three- dimensional knitted objects, but the possible applications are restricted, for example to stockings, and these applications require even more expensive machinery.

The present invention aims a method for manufacturing textile which does not have the above-mentioned disadvantages and which makes it possible to manufacture textile in a fast manner, without any expensive machinery, as a fabric as well as directly in the shape of a three- dimensional object made of fabric material.

This aim is reached according to the invention in that the fabric material is made on the basis of a digital design by means of rapid manufacturing techniques for prototypes, called Rapid Prototyping' .

Such techniques are known for manufacturing mechanical prototypes of objects. With these techniques can be made very fine structures, however, as is described for example in Belgian patent No. 1,008,128. It is unusual to use such techniques for manufacturing fabric material which, as opposed to the aforesaid prototypes, is made of threads and is flexible.

By making use of rapid manufacturing techniques for prototypes, hereafter called Rapid Prototyping', it is not only possible to manufacture fabric materials with different patterns, but also two-dimensional and three- dimensional objects made of fabric material such as a garment, a lamp shade and the like, without any seam.

Preferably, a digital description of the surface of the fabric material is designed in a first stage by means of a computer, the textile pattern is projected on this surface in a second stage, so that a three-dimensional computer model is obtained, and the actual fabric material is made by means of Rapid Prototyping on the basis of said computer model in a following stage. After the second stage, the fabric material can possibly be folded up or slid together in a smaller shape in a digital manner .

According to another embodiment, a digital description of the surface of the fabric material is designed first by means of a computer, and subsequently, on the basis of this description, the fabric material is manufactured by means of Rapid Prototyping, whereby, while the digital surface is being cut into slices during said Rapid Prototyping, a textile pattern is generated and projected in a digital manner onto the sections.

The invention also concerns a device which is particularly suitable for the application of the method according to any of the preceding embodiments.

This device may contain two vessels with a platform which can be moved up and down by means of a lift mechanism, and which has a shaft above the vessels with a scanner on top of it (co-operating with a laser, while means are present to move the vessels and the shaft in relation to one another, so that the shaft is successively situated above the one vessel and then above the other) .

According to another embodiment, the device is a 3D printing machine containing a vessel in the shape of a tube narrowing under a top part ^• which is being heated, a pressure plate that can be pressed onto this part, and a scanner and a laser above this part. In order to better explain the characteristics of the invention, the following preferred embodiment of a method and a device for manufacturing fabric material according to the invention are described as an example only without being limitative in any way, with reference to the accompanying drawings, in which:

figures 1 to 4 represent computer models of pieces of fabric material manufactured according to the invention; figures 5 and 6 represent two computer models of lamp shades manufactured according to the invention; figure 7 represents the computer model of the lamp shade of figure 6 when slid together; figure 8 represents the computer model of a piece of fabric material with loose elements; figure 9 represents the piece of fabric material from figure 8 after being manufactured, and with the elements interlocked in relation to one another; figures 10 to 12 schematically represent a device for the application of the method according to the invention, in three different situations; figure 13 schematically represents another embodiment of a device for the application of the method according to the invention.

In order to manufacture fabric material according to the invention, a digital description, in particular a CAD description, is made of the required two-dimensional or three-dimensional surface of fabric material in a first stage by means of a computer. A two-dimensional surface is a flat surface of a fabric material, whereas a three-dimensional surface is for example a cylindrical or conical surface of for example a lamp shade or a more complicated surface of for example a piece of clothing.

As a second step, a textile pattern, i.e. in particular a weaving, knitting or crochet pattern, is selected and projected onto the above-described surface, so that a three-dimensional computer model with said pattern is obtained.

This can be done by replacing the surface by means of a number of three-dimensional objects on the basis of geometric units.

For a flat surface, the local parameters are identical in every point of the surface. A number of ^control points' can be determined on the surface, and all these control points can be replaced by one and the same basic entity of the textile pattern. By selecting the position of the control points and their mutual distance in a suitable manner, it is possible to manipulate the three-dimensional pattern, for example to a minimum volume or a collapsed representation. This is also possible with cylindrical, spherical and toroidal surfaces.

For more complicated surfaces, for example what are called NURBS (Non Uniform Rational B-splines) , depending on the local parameters of the original surface, for example the local bending and the manner in which the different entities are connected must be adjusted in order to obtain a uniform pattern of objects which do not intersect. This adjustment can be obtained by altering the geometry of the basic entity or by changing the type of connection between the entities, for example into two instead of one joint.

In order to transform a two-dimensional surface into a three-dimensional pattern, it is possible to perform a UV parameterisation of the surface. In such a surface obtained by means of UV parameterisation, every point can be represented by means of its two-dimensional UV coordinates, and vice versa, every pair of UV co-ordinates coincides with a three-dimensional point of the surface. The same algorithm can now be used as for the above- mentioned flat surfaces, with this difference that the basic entities will be calculated in a local co-ordinate system calculated on the original surface and which depends on the local behaviour, for example the bending. This implies that in complex, double bent surfaces, for example NURBS, every entity in the pattern will be different from its neighbouring entities, which makes it virtually impossible to design or manufacture it manually or by making less use of a computer.

Most of the rapid manufacturing techniques for prototypes require a triangulation STL (Standard Triangular Language) file of the object to be built. An STL representation of a complete pattern will require much space from the computer (RAM or disk space) . However, in the above-described manner, the entire pattern can now be represented by means of a list of co-ordinate systems in which the same basic entity must be built in each time. In this manner is required only one sample of the object. All other samples will be calculated again when they are needed. Thus is saved a lot of computer memory and disk space.

The result of the above-described 3D projection is a three- dimensional model with a closed surface, for example in STL format. The computer can generate a 3D image of the future' object, which makes it possible to have a look at the design before starting the rapid manufacturing technique for prototypes or 3D printing techniques.

Figures 1 to 6 represent a number of examples of computer models of textile objects with patterns that can be manufactured. These patterns can be the same as textile patterns made by means of conventional textile machines, but they can also be new and even of such a nature that they cannot possibly be manufactured by means of said textile machines.

Thus, it is possible to manufacture net-like or warp-like patterns in which the basic elements consist of small rings or hexagons or other closed shapes. However, also endless threads can be formed, and objects made thereof can be made of a single thread without beginning nor end. The fabric material may also consist of open rings of varying lengths.

The threads themselves may vary in thickness and/or diameter over their lengths. In a single object can be found different patterns, for example to obtain different bendings or different qualities for the end product. If the object is a garment, parts thereof can be provided with a closing mechanism.

In figures 1 to 4, the objects are computer models of pieces of fabric. In figure 5, the computer model is a cylindrical lamp shade 1 with a thread varying in thickness, and in figure 6 it is a conical lamp shade 2. For the sake of simplicity, only a part of the fabric material is represented in detail in figure 6. It is clear that the entire lamp shade 2 is made of this fabric material.

After the creation of the 3D computer model, the fabric material is usually folded up or slid together in a smaller shape in a digital manner as a third step. This is done by calculating the collision between two particles due to their weight, friction, elasticity and the like, and the necessary forces of nature such as the force of gravity.

Figure 7 represents the model of the lamp shade 2 from figure 6, but after the third step and thus when slid together, namely in the shape of a flat disc.

Thanks to this optional step, it becomes possible to manufacture larger pieces of fabric material or larger objects made of fabric material with a specific Rapid Prototyping machine than when the master model would have to be made. Naturally, when sliding everything together, one must take into account minimal distances in order to be able to separate the threads of the fabric material, so that the model can be telescoped out into its normal shape again after the shaping.

Special patterns can be projected on the surface in order to increase the flexibility of the fabric material during the production, such that the model can be slid together until it has minimal dimensions before the manufacturing or transport. The pattern may thereby be such that its parts, when the fabric material is telescoped out again after the manufacturing, fall into a fixed position in relation to one another. Figures 8 and 9 represent a number of elements 3, namely rings, of such a pattern when being slid together, telescoped out respectively. Every element 3 is provided with a number of protruding loops 4 for meshing in the telescoped-out position after the manufacturing.

The actual manufacturing of the aforesaid computer model which described the threads of the fabric material takes place in a fourth step by means of Rapid Prototyping (RP) .

Use can be made to this end of a selective laser sintering machine, a stereo lithography machine, a 3D printing machine, a Fused deposition Modelling machine or another RP machine that builds up layer after layer with an automatic supply of material.

All these techniques are based on the digital production of slices of the computer model, either or not slid together, after which the RP machine builds up the model layer by layer, in accordance with these slices, for example by means of a controlled laser beam on a photopolymerisable resin.

In order to make it easier to separate the threads of the fabric material after the manufacturing, it is advisable to use an RP machine which does not require any explicit support structures for the material. The technology and the machines of the company ^OBJECT' are therefore more suitable, for example, than the conventional stereo lithography and machines of the company ^λ3D Systems' .

Also 3D printing techniques, for example of the company 'OPTOFORM' , on the basis of paste instead of the conventional resins for stereo lithography are suitable.

The paste makes it possible to avoid supporting structures, and it can be filled with the formed materials which are subsequently sintered in a following step of the manufacturing process. Even coloured textile can be made by means of 3D printing, for example with machines of the firm ^vZ-CORP' .

Selective Laser Sintering (SLS) is suitable as well.

The RP machines that are now available on the market can be used to apply the invention, provided adjusted software is used. However, these machines are disadvantageous in that they have a restricted speed and do not work continuously. Especially for mass production or large-scale manufacturing, a rapid, continuous process is required, however.

The restricted speed is due to the fact that the existing RP machines are not fit to manufacture a large number of very small sections, as is required for fabric material.

This speed problem can be solved by making use of inkjetlike systems as are used in the existing systems of among others the companies 'OBJECT' , 'Z-CORP' and EXTRUDE-HONE' . The printing process can be speeded up by placing more extruder heads in parallel. Systems that are based on scanning are more difficult to adapt. Since they scan vectors, it would be necessary to place several scanners in parallel, which each scan a specific surface area.

The non-continuous working of the existing RP machines is due to the fact that they comprise a vessel with a platform which is lowered step by step to the bottom thereof, upon which the built object is situated. When this platform is situated on the bottom and the vessel is thus full, these known machines must be stopped, emptied and started again, which results in a great loss of time.

In order to solve this problem, it is possible to use a semi-continuous RP device for systems working with powder such as SLS, inkjet-based 3D systems and systems based on paste, as is schematically represented in figures 10 to 12.

This device comprises two vessels 5 whose bottom forms a platform 6 which can be moved up and down by a lift mechanism 7. The two vessels 5 are erected next to one another on a carriage 8. Above the vessels 5 is erected a fixed shaft 9 which, depending on the position of the carriage 8, rests on one or the other vessel 5. Above this shaft 9 is erected the scanner 10 onto which the laser 11 is directed.

When the platform 6 has reached its lowest position in the vessel 5 situated under the shaft 9, the carriage 8 is moved until the other vessel 5, whose platform 6 is situated at the top, is situated under the shaft 9. While objects are being formed by means of RP in the latter shaft 9, the first vessel 5 can be emptied. Figure 10 represents the situation while the one vessel 5 is being used, and figure 12 while the other vessel 5 is in use, whereas figure 11 represents the situation while the carriage 8 is being moved.

The platform 6 must not necessarily form a movable bottom for the vessel 5. The vessel 5 may be closed at the bottom, while the platform can be moved up ^' and down above said bottom. Instead of the vessels 5 being movable, the shaft 9 may be moved together with the laser 11 and the scanner 10 in relation to stationary vessels 5.

The device which is schematically represented in figure 13 allows for a continuous production. This device is a 3D printing machine with a single vessel in the shape of a tube 12, without any platform. Underneath a top part 13, which is heated, the tube 12 narrows. A pressure plate 14 is hinge-mounted on this part which can be pushed on the tube 12 by means of a piston mechanism 15. Above the part 13 are erected the scanner 10 and the laser 11, while the lower open end of the tube 12 opens into a basin 16.

Each time a layer of the textile model has been printed in the part 13, this layer is pushed into the tube 12 by means of the pressure plate 14. The printed fabric material is pushed a little further in the tube 12 with each layer, where it cools down, until it falls from the tube 12 in the basin 16 below, together with the unused powder or the unused paste. 'The fabric material can then be separated from the powder or the paste.

If the computer model had been folded up or slid together, also the real model that was made by means of Rapid Prototyping will be folded up or slid together. As a final step, the elements can then be unfolded or telescoped out. This may be done for example after the transport, so that the volume during the transport is minimal.

According to the above-described method, the computer model may become rather large in the second stage, i.e. the 3D projection of the textile pattern on the surface, which requires much calculating time with the existing computers in order to manufacture it.

According to a variant of the method, the above-mentioned disadvantage can be avoided by generating the textile pattern and by projecting it on the sections obtained while cutting the surface in slices during the Rapid Prototyping. As a result, the computer model will remain smaller and less computer memory will be required. The printing of the sections of the fabric fibres is generated on the flight, during the printing process itself. However, the algorithm for making the sections is more complex, and it will not be possible to carry out the third step, i.e. the folding up or sliding together.

As already mentioned, it is possible to make fabric material with possibly completely new patterns in the above-described manners, or objects made of such fabric material such as T-shirts, pants or other garments, curtains, napkins and the like, all seamless. Also 3D fabric materials can be manufactured. The fabric material may look as the computer models represented in figures 1 to 4. Fabric material must be understood in a very large sense here, so that not only woven fabric, but also knitwear and crochet work must be understood by it, as already mentioned, and even nets, plaiting, and the like.

If the human body is scanned in, this information can be used in a 3D CAD program to design the above-mentioned computer model. The above-described method then allows to make a piece of clothing which fits perfectly on this body.

Also other and even large objects of 'fabric material' in the broadest sense can be manufactured, such as the lamp shades corresponding to the computer model according to figures 5 and 6. Parts or elements of the fabric material may mesh or may be interlocked, for example as represented in figure 9, so that a rigid and relatively strong whole is obtained.

The produced fabric material can also be reinforced in other manners, for example by means of impregnation, coating, sintering, etc. Thus, the conical lamp shade represented in figure 6 may be sprinkled with resin or glue, or when it is made of nylon, it can be sintered in an oven at 200°C.

The invention is by no means limited to the above-described embodiments represented in the accompanying drawings; on the contrary, such a method and device for manufacturing fabric material can be made in all sorts of variants while still remaining within the scope of the invention.

Claims

Claims .

1. Method for manufacturing fabric material, characterised in that the fabric material is manufactured on the basis of a digital design by means of Rapid Prototyping.

2. Method according to claim 1, characterised in that a digital description of the surface of the fabric material is designed in a first step by means of a computer, in that a textile pattern is projected onto this surface in a second step, so that a three- dimensional computer model is obtained, and in that the fabric material is manufactured on the^' basis of this computer model by means of Rapid Prototyping in a subsequent step.

3. Method according to claim 2, characterised in that, after the second step, the fabric material is folded up or slid together in a smaller shape in a digital manner.

4. Method according to claim 3, characterised in that parts of the fabric material are provided with locking means (4) with which they mesh or are interlocked when they are telescoped out or unfolded again after the rapid prototyping.

5. Method according to claim 1, characterised in that a digital description of the surface of the fabric material is designed by means of a computer first, and in that the fabric material is subsequently manufactured by means of Rapid Prototyping on the basis of this description, whereby a textile pattern is generated while the surface is cut into slices during said Rapid Prototyping, and is digitally projected onto the sections.

6. Method according to any of the preceding claims, characterised in that in one and the same object of the fabric material, depending on the place, the shape or section of the threads is locally altered, or the textile pattern is locally adjusted.

7. Device for manufacturing fabric material according to any of the preceding claims, characterised in that it comprises two vessels (5) with a platform (6) which can be moved up and down by means of a lift mechanism (7), and which has a shaft (9) above the vessels (5) with a scanner (10) on top of it co-operating with a laser (11) , while means (8) are present to move the vessels (5) and the shaft (9) in relation to one another, so that the shaft (9) is successively situated above one vessel (5) and then above the other.

8. Device for manufacturing fabric material according to any of the preceding claims, characterised in that it comprises a 3D printing machine containing a vessel in the shape of a tube (12) narrowing under a top part (13) which is being heated, a pressure plate (14) that can be pressed onto this part (13), and a scanner (10) and a laser (11) above this part (13) .