TWI554977B - Method for the combination of 3d models - Google Patents

Description

3D model expansion method

The invention is a three-dimensional printing field, in particular a method for expanding a 3D model.

3D Printing is a rapid prototyping technique. By registering the data of the 3D model file drawn by the designer into the 3D printer, using the adhesive material such as powder metal or plastic, the material is stacked in a layer-by-layer manner to form the final product. This implementation of 3D printing is known in the industry as Additive Manufacturing and is contrary to traditional material removal methods. By adding materials, based on 3D CAD model data, layer-by-layer manufacturing is often used. The method of directly manufacturing a three-dimensional physical solid model that is completely consistent with the corresponding mathematical model is characterized by being capable of producing articles of any shape.

In recent years, the three-dimensional printing technology has developed rapidly and has received more and more attention. The manufacturers have also developed various three-dimensional printing technologies according to different needs. However, traditional 3D models cannot combine multiple individual 3D models into new models. When multiple models need to be combined for a certain need, a new model with multiple model characterization information has to be recreated.

In order to make the combination of multiple 3D models more convenient and avoid resource consumption caused by re-opening, the present invention provides a method for expanding a 3D model for combining a first model and a second model into a new model, the method comprising Obtaining the characterization information of the first model and the second model; superimposing the characterization information of the second model on the first model to form a third model; and filling the first model and the third model The gap creates the new model.

Preferably, the first model and the second model are composed of a plurality of points, and the characterization information is a coordinate value of each point.

Preferably, when the first model and the second model are represented by the two-dimensional image, the characterization information of the first model and the second model is presented by the depth of the color of the two-dimensional image.

Preferably, when the first model and the second model are transmitted through the two-dimensional image, the two-dimensional image is rotated, stretched, and extruded to obtain features of the first model and the second model. Information.

Preferably, the method for superimposing the characterization information of the second model to the first model further comprises: acquiring the second model; reading the characterization information of the second model; and combining according to the position of the first model The characterization information of the second model forms a third model outside the first model.

Preferably, the method for forming the third model further comprises: Projecting the points constituting the second model along a direction of the first normal vector to a first reference plane, and obtaining respective projection points of the second model points projected onto the first reference plane, forming a point from the respective points a distance between each connection line of the first reference plane, and respectively calculating a length of each connection distance; providing the first model, and designating any three-point coordinates in the first model to obtain a plane; The slice formed by the model is a reference plane, and the normal vector of the reference plane is a second normal vector, so that the reference plane moves along the direction of the second normal vector toward the surface of the first model, when moving Stopping the movement when the ratio of the reference plane generated by the first model to the area of the reference plane and the area of the reference plane is less than a predetermined value, so that the reference plane that stops moving is a second reference plane; a center point of the plane overlaps with a center point of the first reference plane to obtain a plurality of intersection points, and each of the projection points is increased according to a normal vector of the first reference plane, and correspondingly corresponding to the plurality of intersection points The length of the distance of the connection, and according to the characteristic information of the second model to form the third model.

Preferably, the method for forming a distance from each point to the first reference plane includes: acquiring any three points on the first reference plane; and acquiring a normal vector of the first reference plane according to the acquired three points. And moving the points of the second model in a direction of the first normal vector to intersect the first reference plane.

Preferably, the first model and the second model are both represented in the form of a 3D model file to be printed.

The invention proposes an expansion method of a 3D model, that is, a scheme of combining a plurality of models into a new model. The characterization information of the first model and the second model is first obtained, and then the characterization information of the second model is superimposed on the first model to form a new model. In this way, based on the original model, we can add the characterization information we need, which not only improves the flexibility and sensitivity, but also reduces the resource consumption of making new models. In addition, as long as these characterization information has the conditions for converting it into a 3D model, the application surface is also extensive. In addition, based on the original model, the characterization information is added, and the small characterization information can protect the property rights information of the product. The larger characterization information can be used for product exhibition and publicity.

P‧‧‧Second model

A1, A2, A3...An‧‧‧ points

B‧‧‧First datum plane

B1, B2, B3...Bn‧‧‧ points

C‧‧‧ reference plane

C’‧‧‧second datum plane

W1‧‧‧ first normal vector

W2‧‧‧ second normal vector

H1, h2, h3...hn‧‧‧ distance

M‧‧‧ first model

P1‧‧‧ third model

C1, C2, C3...Cn‧‧‧ points

V1, V2, V3...Vn‧‧‧ points

Z1, Z2, Z3...Zn‧‧‧ points

X, Y, Z‧‧‧ coordinate axis

S1~S3‧‧‧ steps

1 is a schematic diagram of a second model in a method for expanding a 3D model according to an embodiment of the present invention; and FIG. 2 is a schematic diagram of a method for expanding a 3D model according to an embodiment of the present invention; A schematic diagram of a line; FIG. 3 is a schematic diagram of forming a third model in an extension method of a 3D model according to an embodiment of the invention.

FIG. 4 is a flowchart of a method for expanding a 3D model according to an embodiment of the present invention.

The invention will be further described in detail below with reference to the drawings and specific embodiments. Advantages and features of the present invention will become more apparent from the description. It should be noted that the drawings are in a very simplified form and all use non-precision proportions, which are only used to facilitate and clarify the explanation. The purpose of the embodiments of the invention is set forth.

The method for expanding the 3D model provided by the present invention integrates the characterization information of the two models and forms a new 3D model file before printing, and then prints the new 3D model file. As shown in FIG. 4, it is a flowchart of a method for expanding a 3D model according to an embodiment of the present invention. The basic steps include: Step S1: acquiring feature information of the first model and the second model; Step S2: The characterization information of the second model is superimposed on the first model to form a third model; and step S3: filling a gap between the first model and the third model to form a new model.

Usually, since the first model and the second model are both 3D graphics, they are represented by 3D data. However, if a two-dimensional image representation is used, it can also be converted into 3D data and its characterization information can be obtained. For example, the algorithm can be used to render the characterization information of the first model and the second model by using the depth of the color of the two-dimensional image. The characterization information can be, for example, the original version of the third model to be formed, and the original Is a three-dimensional model or a two-dimensional image that is formed into a three-dimensional model by other means, wherein the depth of light can represent the coordinates of the XYZ axis according to, for example, the RBG value of the color; or can be rotated and pulled by the two-dimensional image. The characterization information of the model is obtained by stretching, squeezing or contour chamfering to form a three-dimensional model of the two-dimensional image.

In the present invention, the method of superimposing the characterization information of the second model to the first model comprises: acquiring the second model; reading the characterization information of the second model; and combining according to the position of the first model Characterized information of the second model, Forming a third model outside the first model; and filling a gap between the first model and the third model to form a new model.

It can be seen that the superposition of the two model characterization information needs to first form the third model outside the first model, the third model combining the features of the first model surface and incorporating the features of the second model. Then, filling the gap between the first model and the third model completes the combination of the first model and the second model. In the above, for example, the second model is used to describe the characterization information of the third model, and the third model is a replica of the second model, and the first model and the third model are combined. After the model, the final combined model is available.

The method of forming the third model will be described in detail below with an example. In this embodiment, the first model and the second model are composed of a plurality of points, and the characterization information is a coordinate value of each point. As shown in FIG. 1 , FIG. 1 is a schematic diagram of the second model P, which is now superimposed on the first model to form the third model. The specific method includes:

1. Taking a first reference plane, the first reference plane does not pass through the interior of the second model and can simultaneously include the most tangent point of the second model surface, and the range of the first reference plane is parallel to the first reference plane The range of the largest periphery of the second model section is the same, for example, a multi-angled stone is placed flat on the table. The normal vector of the first reference plane is a first normal vector.

Projecting the points constituting the second model to the first reference plane along the direction of the first normal vector, and obtaining respective projection points of the second model points projected onto the first reference plane, forming the projection points to Each line of the second model calculates the length of each connection line. In other words, the length of each connection line of the second model is only for calculating the points of the second model relative to the first reference plane. The distance, in addition, each point of the second model may be arbitrarily selected n points on the surface of the second model; As shown in FIG. 2, the reading satisfies "the first reference plane does not pass through the interior of the second model and can include the cut point of the second model surface at the same time, and the range of the first reference plane is parallel to the first The range of the maximum outer periphery of the second model section of the reference plane is the same. Any three-point coordinate of the first reference plane B of the condition, and the normal vector of the first reference plane B is obtained according to the vector formula as the first normal vector W1 (0, 1,0). The coordinates (2, 4, 2) of the point A1 on the second model P, the coordinates (3, 2, 5) of the point A2, and the coordinates (4, 2, 3) of the point A3 are read. Moving the points A1, A2, A3..An along the direction of the first normal vector W1 toward the first reference plane B, the coordinates (2, 0, 2) and projections intersecting the first reference plane B at the projection point B1 The coordinates (3, 0, 5) of the point B2 and the coordinates (4, 0, 3) ... Bn of the projection point B3, thereby obtaining the connection distance h1 between the point A1 and the projection point B1, and the connection of the point A2 and the projection point B2. The distance h2, the connection distance h3 between the point A3 and the projection point B3, the connection distance hn of the point coordinate An and the projection point coordinate Bn, that is, the points on the second model P and the projection points of the first reference plane respectively have a corresponding Connection distance hh.

It should be noted that the points A1 to An on the second model P are only illustrative, and the points are arbitrary. Only all the points taken together can reflect the characteristic information of the second model. can. In general, the more the number of points taken, the more accurate the reflection of the second model P feature.

2. Providing a first model, and designating any three-point coordinates in the first model to obtain a plane, such that the plane formed by the plane and the first model is a reference plane, and the normal vector of the reference plane is the second method a vector, the reference plane is moved along the second normal vector to a direction shorter than the surface of the first model, and the ratio of the area of the plane of the moving reference plane to the first model and the area of the reference plane is less than one When the preset value is stopped, the reference plane that stops moving is a second reference plane; as shown in FIG. 3, any three points C1 and C2 in the first model M are read. The coordinates (0, 2, 1), (0, 2, 2), (1, 3, 3) of C3 obtain a plane according to the three points C1, C2, and C3, and take the plane formed by the plane and the first model. It is a reference plane C, which is composed of C1, C2, C3...Cn points. On the reference plane C, C1, C2, and C3 (three points can be arbitrarily taken, for example) are calculated, and the second normal vector W2 of the reference plane C is obtained as (1, -1, 0) along The second normal vector W2 moves the reference plane C at a direction closer to the surface of the first model M, and the ratio of the area of the cut plane generated by the reference plane C and the first model to the reference plane area is less than 2 When % is stopped, the reference plane that stops moving is a second reference plane C', which is composed of points V1, V2, V3...Vn. In this embodiment, the first model M is a vertebral body or an arbitrary cube, but the invention is not limited thereto.

3. Find the center point of the second reference plane C' and superimpose it on the center point of the first reference plane B. If the two overlap, it can be inferred that there will be at most n intersection points (ie, the first reference plane n) Each of the projection points is formed according to the normal vector of the first reference plane B, and the intersection distances of the n reference points are respectively increased, and the eigenvalues of the second model are added to calculate the third model.

As shown in FIG. 3, at the n intersections (projection points) where the two overlap, when the first reference plane B and the second reference plane C' intersect at V1, V2, V3, ..., Vn, and each projection Point Bn has a corresponding connection distance hn (n can be substituted into 1~n) to find the vector , , ...... Afterwards, points Z1, Z2, Z3...Zn are taken on the extension lines of the vectors, so that , , ...... Then, the third model P1 is obtained from the points Z1, Z2, Z3, ... Zn.

After the third model P1 is formed by the above method, the gap between the surface of the first model M and the third model P1 is filled, that is, the filling points C1, C2, C3, ..., Cn and points, respectively. The space between V1, V2, V3...Vn, and the space between points V1, V2, V3...Vn and point Z1, Z2, Z3...Zn, respectively, such as the extension line of each point is not solid, thereby forming the final The combination model completes the expansion and integration of the model.

The invention proposes a scheme for combining a plurality of models into a new model, and the first model and the second model can be combined into a new model, and the characterization information of the first model and the second model is first obtained, and then the first The characterization information of the second model is superimposed on the first model to form a new model. In this way, based on the original model, we can add the characterization information we need, which not only improves the flexibility and sensitivity, but also reduces the resource consumption of making new models. In addition, as long as these characterization information has the conditions for converting it into a 3D model, the application surface is also extensive. In addition, based on the original model, the characterization information is added, and the small characterization information can protect the property rights information of the product. The larger characterization information can be used for product exhibition and publicity.

It will be apparent to those skilled in the art that various modifications and variations can be made in the invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of the inventions

M‧‧‧ first model

P1‧‧‧ third model

C‧‧‧ reference plane

C’‧‧‧second datum plane

M2‧‧‧ second normal vector

C1, C2, C3...Cn‧‧‧ points

H1, h2, h3...hn‧‧‧ distance

Z1, Z2, Z3...Zn‧‧‧ points

V1, V2, V3...Vn‧‧‧ points

X, Y, Z‧‧‧ coordinate axis

Claims (7)

An expansion method of a 3D model for combining a first model and a second model into a new model, the steps comprising: acquiring a characterization information of the first model and the second model; Superimposing the characterization information on the first model to form a third model; and filling a gap between the first model and the third model to form the new model; wherein the characterization information of the second model The method of superimposing to the first model further includes: acquiring the second model; reading the characterization information of the second model; and combining the characterization information of the second model according to the location of the first model, The third model is formed outside the first model. The method for expanding a 3D model according to claim 1, wherein the first model and the second model are composed of a plurality of points, and the characterization information is a set value of each point. The method for expanding a 3D model according to claim 1, wherein when the first model and the second model are represented by a two-dimensional image, the first model is presented by the depth of the color of the two-dimensional image. And the characterization information of the second model. The method for expanding a 3D model according to claim 1, wherein when the first model and the second model are represented by a two-dimensional image, the two-dimensional image is rotated, stretched, and squeezed. Pressing and contour chamfering to obtain the characterization information of the first model and the second model. The method for expanding a 3D model according to claim 1, wherein the method for forming the third model further comprises: projecting each of the points constituting the second model along a direction of a first normal vector to a first a reference plane, each projection point of the second model is obtained to be projected to the first reference plane, forming a line distance from each point to the first reference plane, and calculating the length of each connection distance Providing the first model, and designating any three-point coordinates in the first model to obtain a plane; the plane formed by the plane and the first model is a reference plane, and the normal vector of the reference plane is a second normal vector such that the reference plane moves along the direction of the second normal vector toward the surface of the first model, and the reference plane generated by the reference plane and the first model in motion and the reference plane When the ratio of the area is less than a preset value, the movement is stopped, and the reference plane that stops moving is a second reference plane; the center point of the second reference plane is overlapped with the center point of the first reference plane to obtain a plurality of intersection points, wherein each of the projection points is based on a normal vector of the first reference plane, and a length corresponding to each of the plurality of intersection points is increased, and the characterization information is formed according to the second model to form The third model. The method for expanding a 3D model according to claim 5, wherein the method for forming each of the connection distances from the points to the first reference plane comprises: acquiring any three points on the first reference plane; Obtaining the first normal vector of the first reference plane according to the acquired three points; Each point of the second model is moved in a direction of the first normal vector to intersect the first reference plane. The method for expanding a 3D model as described in claim 1, wherein the first model and the second model are both in the form of a 3D model file to be printed.