METHOD AND APPARATUS FOR AUTOMATIC SUPPORT GENERATION FOR AN OBJECT MADE BY MEANS OF A RAPID PROTOTYPE PRODUCTION METHOD

• US 20150151494A1
• Filed: 12/01/2014
• Published: 06/04/2015
• Est. Priority Date: 10/10/2007
• Status: Active Grant

• Current Assignee: Materialise NV
• Original Assignee: Materialise NV
• Inventors: RENAP, Kurt, EGGERS, Gerald
• Granted Patent: US 10,343,389 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B29C 64/386 Data acquisition or data processing for additive manufacturing
• CPC Class Codes: B29C 64/40 Structures for supporting 3D objects during manufacture and intended to be sacrificed after completion thereof
• CPC Class Codes: B33Y 50/00 Data acquisition or data processing for additive manufacturing
• CPC Class Codes: B33Y 50/02 for controlling or regulating additive manufacturing processes
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: G05B 15/02 electric
• CPC Class Codes: G06T 17/10 Constructive solid geometry [CSG] using solid primitives, e.g. cylinders, cubes
• CPC Class Codes: G06T 19/00 Manipulating 3D models or images for computer graphics

Abstract

The present invention is directed to an improved method for supporting an object made by means of stereo lithography or any other rapid prototype production method. The generation of the support begins by determining the region that requires support in each layer of the object and defines a number of support points in this region. In a next step, a support mesh is generated connected to the object using these support points. The present invention also discloses different techniques that reduce superfluous edges to further optimize the support mesh. Finally, a support is generated from this support mesh. The present invention may facilitate the generation of supports data by employing more automation and less user analysis.

Claims

1. A method of generating support structure data for a three-dimensional object comprising the steps of:

receiving first object layer data describing a first layer of an object;

defining a support region within the first layer;

defining a first support point within the support region;

defining an external support mesh for the object comprising a plurality of nodes connected by a plurality of edges; and

defining a connection edge between the first support point of the object and a selected node of the external support mesh.

2. The method of claim 1, wherein the support region within the first layer of the object is defined by comparing the first object layer data to second object layer data describing a second layer underlying the first layer.

3. The method of claim 2, wherein the support region within the first layer is offset in a first direction from a first layer boundary to account for the self-supporting capacity of the second layer.

4. The method of claim 1, further comprising:

dividing the support region into a coarse support region and a detailed support region.

5. The method of claim 4, further comprising:

defining a first boundary offset inwardly from a border of the support region by an offset distance;

defining a second boundary offset outwardly from the first boundary by the offset distance;

wherein the second boundary forms the coarse support region boundary; and

wherein the detailed support region comprises the difference between the support region and the coarse support region.

6. The method of claim 2, wherein comparing the first object layer data to the second object layer data comprises calculating a Boolean difference between the first object layer data and the second object layer data.

7. The method of claim 5, further comprising:

defining a plurality of second support points within the coarse support region, wherein the second support points are distributed on the first boundary, and the distance between neighboring second support points is less than a first predefined distance.

8. The method of claim 7, wherein the first predefined distance is equal to two times a critical overhang distance.

9. The method of claim 4 further comprising:

defining a plurality of detailed support region support points that are distributed on a skeleton of the detailed support region.

10. The method of claim 1, wherein at least some of the plurality of nodes and plurality of edges of the external support mesh form a rhombus pattern.

11. The method of claim 1, further comprising:

modifying the first object layer data to account for a beam width of the layer.

12. The method of claim 1, further comprising:

removing one or more edges of the external support mesh.

13. The method of claim 1, wherein defining the external support mesh comprises:

subtracting each layer of the object from the external support mesh.

14. The method of claim 1, wherein the selected node is the closest node in the external support mesh to the support point.

15. The method of claim 14, wherein the external support mesh is a shortest path external support mesh.

16. The method of claim 1, wherein the external support mesh is a columnar mesh.

17. The method of claim 1, further comprising:

producing the object and the external support mesh using a rapid prototype production method.