CN105014971B - 3D printing method - Google Patents

Abstract

The invention discloses a 3D printing method, comprising the following steps: selecting a printing object and establishing a preliminary model; establishing a three-dimensional space coordinate axis on the basis of the preliminary model, dividing the surface of the preliminary model into several triangles, and recording the coordinates of the vertices of each triangle; The preliminary model is internally divided into several hexahedrons, and the coordinates of the vertices of each hexahedron are recorded; the vertices of the hexahedron with the closest spatial distance to the triangles on the surface of the preliminary model are connected with the vertices of each triangle to form an external tetrahedron; the three-dimensional space coordinates of all connecting line segments on the preliminary model are obtained ; Materialize all connected line segments and print them to obtain a structured print product. The invention subdivides the preliminary model of the printing object before printing to structure the printing object, and can print out a porous structure, which can better promote bone ingrowth, and is convenient for application in the medical device industry.

Description

A 3D printing method

technical field

The present invention relates to 3D printing technology, in particular, to a 3D printing method.

Background technique

3D printing is a kind of rapid prototyping technology. It is a technology based on digital model files and using bondable materials such as powdered metal or plastic to construct objects by layer-by-layer printing. In the existing 3D printing technology, after modeling the printed object, the method of printing all the structures at one time is usually adopted, so that the printed product and the printed object are exactly the same. However, in the medical field, the applicability of the exact same structure as the printed object is not good after implantation. The porous structure is more conducive to the recovery after implantation, but this cannot be achieved by existing technologies.

Contents of the invention

In order to overcome the deficiencies of the prior art, the object of the present invention is to provide a 3D printing method, which divides the preliminary model of the printed object before printing, and structures the printed object, which can print out a porous structure, and can better Promote bone ingrowth and facilitate the application in the medical device industry.

In order to solve the above problems, the technical scheme adopted in the present invention is as follows:

A 3D printing method, comprising the steps of:

1) Select the object to be printed and build a preliminary model;

2) Establish a three-dimensional space coordinate axis on the basis of the preliminary model, and divide the surface of the preliminary model into several triangles, and record the coordinates of the vertices of each triangle;

3) Divide the preliminary model into several hexahedrons, and record the coordinates of the vertices of each hexahedron;

4) judging the spatial distance between each hexahedron vertex and each triangle on the preliminary model surface, connecting the hexahedron vertex with the nearest spatial distance to each triangle vertex on the preliminary model surface to form an external tetrahedron;

5) according to step 2)-4) in each triangle vertex and each hexahedron vertex coordinate and connection relation, obtain the three-dimensional space coordinate of all connecting line segments on the preliminary model;

6) Realize all the connecting line segments in step 5), set the printing diameter of the line segments, and perform printing processing to obtain a structured printing product.

Preferably, the method for establishing the preliminary model in step 1) is 3D modeling technology or 3D scanning technology.

Preferably, each hexahedron in the step 3) is a cube.

Preferably, the step 3) further includes the step of: randomly selecting a point in each hexahedron, and dividing the hexahedron into several inner tetrahedrons.

Preferably, the printing diameter of the line segments in step 6) is 0.3-0.6 mm.

Compared with the prior art, the beneficial effects of the present invention are:

The invention divides the preliminary model of the printing object before printing, and the printing object is structured, and the porous structure can be printed, which can better promote bone ingrowth and facilitate the application in the medical device industry; the hexahedron in the present invention can be a cube , to a certain extent reduce the calculation amount and increase the calculation speed; the invention divides the hexahedron into tetrahedrons, and utilizes the stability of the triangle to enhance the stability of the later printing products.

Description of drawings

Fig. 1 is the printing object in the embodiment of the present invention 1 and 2;

Fig. 2 is a printing effect diagram in Embodiment 1 of the present invention;

Fig. 3 is a printing effect diagram in Embodiment 2 of the present invention.

detailed description

The present invention will be further described in detail below in combination with specific embodiments.

The 3D modeling technology, the 3D scanning technology and the 3D printing technology applied after modeling involved in the present invention are all prior art.

Example 1

Adopt the method of the present invention to carry out 3D printing to the printing object (cancellous bone structure with a diameter of 25mm) in Fig. 1, comprising the following steps:

1) Use 3D modeling technology to establish a preliminary model of the printed object;

2) Establish a three-dimensional space coordinate axis on the basis of the preliminary model, and divide the spherical surface of the preliminary model into 2.92*10 ³ triangles, and record the coordinates of the vertices of each triangle;

3) Divide the preliminary model internally into 2.4*10 ⁴ hexahedrons, and record the coordinates of the vertices of each hexahedron; randomly select a point in each hexahedron, and divide the hexahedron into 2.8*10 ⁵ internal tetrahedra;

4) judging the spatial distance between each hexahedron vertex and each triangle on the preliminary model surface, connecting the hexahedron vertex with the nearest spatial distance to each triangle vertex on the preliminary model surface to form an external tetrahedron;

5) according to step 2)-4) in each triangle vertex and each hexahedron vertex coordinate and connection relation, obtain the three-dimensional space coordinate of all connecting line segments on the preliminary model;

6) Solidify all the connecting line segments in step 5), and set the printing diameter of the line segments to 0.3 mm, and perform conventional 3D printing processing to obtain a porous structure (see Figure 2).

Example 2

Adopt the method of the present invention to carry out 3D printing to the printing object (cancellous bone structure with a diameter of 25mm) in Fig. 1, comprising the following steps:

1) Use 3D scanning technology to establish a preliminary model of the printed object;

2) Establish a three-dimensional space coordinate axis on the basis of the preliminary model, and divide the surface of the preliminary model into 2.84*10 ³ triangles, and record the coordinates of the vertices of each triangle;

3) Divide the preliminary model internally into 2.62*10 ⁴ cubes, and record the coordinates of the vertices of each cube; take any point in each cube, and divide the cube into 3.14*10 ⁵ internal tetrahedrons;

4) Judging the spatial distance between each cube vertex and each triangle on the preliminary model surface, connecting the nearest cube vertex with each triangle vertex to form an external tetrahedron with the spatial distance of each triangle on the preliminary model surface;

5) according to step 2)-4) in each triangle vertex and each cube vertex coordinate and connection relation, obtain the three-dimensional space coordinate of all connecting line segments on the preliminary model;

6) Realize all the connecting line segments in step 5), set the printing diameter of the line segment to 0.6 mm, and perform printing processing to obtain a structured printing product (see figure).

The porous structure obtained in Examples 1 and 2, due to its internal porosity, grows into the bone body after implantation, which is more conducive to recovery, while the implantation of the printed object in Figure 1 has a longer recovery period and has a higher degree of adaptability in the body. slightly worse.

Those skilled in the art can make various other corresponding changes and deformations according to the above-described technical solutions and concepts, and all these changes and deformations should fall within the protection scope of the claims of the present invention.

Claims (5)

1. A 3D printing method, comprising the following steps: 1) Select the object to be printed and build a preliminary model; 2) Establish a three-dimensional space coordinate axis on the basis of the preliminary model, and divide the surface of the preliminary model into several triangles, and record the coordinates of the vertices of each triangle; 3) Divide the preliminary model into several hexahedrons, and record the coordinates of the vertices of each hexahedron; 4) judging the spatial distance between each hexahedron vertex and each triangle on the preliminary model surface, connecting the hexahedron vertex with the nearest spatial distance to each triangle vertex on the preliminary model surface to form an external tetrahedron; 5) according to step 2)-4) in each triangle vertex and each hexahedron vertex coordinate and connection relation, obtain the three-dimensional space coordinate of all connecting line segments on the preliminary model; 6) Realize all the connecting line segments in step 5), set the printing diameter of the line segments, and perform printing processing to obtain a structured printing product. 2. The 3D printing method according to claim 1, characterized in that, the method for establishing the preliminary model in the step 1) is 3D modeling technology or 3D scanning technology. 3. The 3D printing method according to claim 1 or 2, characterized in that, in the step 3), each hexahedron is a cube. 4. The 3D printing method according to claim 3, characterized in that, said step 3) further comprises the step of: randomly selecting a point in each hexahedron, and dividing the hexahedron into several internal tetrahedrons. 5. The 3D printing method according to claim 4, characterized in that, the printing diameter of the line segments in the step 6) is 0.3-0.6 mm.