Method for printing three-dimensional parts with part strain orientation

Patent metadata

Field	Value
Publication number	US-9925725-B2
Application number	US-201715581663-A
Country	US
Kind code	B2
Filing date	Apr 28, 2017
Priority date	Mar 10, 2014
Publication date	Mar 27, 2018
Grant date	Mar 27, 2018

Abstract

A method and program for printing a three-dimensional part with an additive manufacturing system, the method including generating or otherwise providing strain data from a digital model of the three-dimensional part, orienting the digital model to align the directions of high tensile strain in a build plane, and printing the three-dimensional part in a layer-by-layer manner based on the oriented digital model with the additive manufacturing system.

First claim

The invention claimed is:

1. A method for printing a three-dimensional part with an additive manufacturing system, the method comprising:
providing a digital model of the three-dimensional part to a computer-based system;
generating strain data from the digital model with the computer-based system, wherein generating the strain data comprises generating strain tensors for a plurality of voxels of the digital model;
determining a dominant tensile strain direction for the digital model from the strain data with the computer-based system;
selecting an orientation for the digital model in a coordinate system based at least in part on the determined dominant tensile strain direction; and
generating printing instructions from the oriented digital model with the computer-based system.

2. The method of claim 1 , wherein the method further comprises saving one or more files of the generated strain tensors to one or more storage media of the computer-based system.

3. The method of claim 1 , wherein the generated strain tensors for the digital model comprise diagonalized strain tensors.

4. The method of claim 1 , and further comprising:
slicing the oriented digital model into a plurality of sliced layers with the computer-based system, wherein the plurality of sliced layers comprise a first sliced layer;
separating the first sliced layer into a plurality of sub-regions with the computer-based system, wherein the plurality of sub-regions comprises a first sub-region;
calculating volume-averaged tensile strains for the first sub-region from the strain data with the computer-based system;
comparing, with the computer-based system, at least one of the calculated volume-averaged tensile strains to an elastic limit for a part material used to print the three-dimensional part; and
generating one or more interior fill tool paths for the first sub-region based on the comparison with the computer-based system.

5. The method of claim 1 , and further comprising determining a secondary tensile strain direction for the digital model from the strain data with the computer-based system, wherein orienting the digital model also includes aligns the secondary tensile strain direction in the build plane of the additive manufacturing system.

6. The method of claim 5 , and further comprising calculating volume-averaged tensile strains from the strain data with the computer-based system, wherein the calculated volume-averaged tensile strains comprise a highest volume-averaged tensile strain and a second highest volume-averaged tensile strain, wherein determining the dominant tensile strain direction from the strain data comprises assigning a first coordinate direction for the highest volume-averaged tensile strain as the dominant tensile strain direction, and wherein determining the secondary tensile strain direction from the strain data comprises assigning a second coordinate direction for the second highest volume-averaged tensile strain as the secondary tensile strain direction.

7. The method of claim 6 , wherein calculating the volume-averaged tensile strains from the strain data comprises calculating weighted volume-averaged tensile strains from the strain data and from one or more weighted values.

8. The method of claim 1 , and further comprising:
transmitting the generated printing instructions from the computer-based system to the additive manufacturing system; and
printing the three-dimensional part in a layer-by-layer manner based on the transmitted printing instructions.

9. The method of claim 1 , and further comprising:
separating the digital model into sub-models based on the generated strain data with the computer-based system, wherein orienting the digital model comprises orienting a first sub-model of the sub-models, and wherein generating the printing instructions from the oriented digital model comprises generating the printing instructions from the oriented first sub-model; and
printing a first sub-part in a layer-by-layer manner based on the generated printing instructions.

10. The method of claim 9 , wherein the first-sub part is printed from a first part material, and wherein the method further comprises:
orienting a second sub-model of the sub-models with the computer-based system;
printing a second sub-part of the three-dimensional part in the layer-by-layer manner based on the oriented second sub-model, wherein the second sub-part is printed from a second part material that is different from the first part material; and
assembling the first sub-part and the second sub-part together produce at least a portion of the three-dimensional part.

11. A method for printing a three-dimensional part with an additive manufacturing system, the method comprising:
performing a finite element analysis on a digital model with a computer-based system to produce a plurality of strain tensors each associated with a voxel of the digital model;
calculating volume-averaged tensile strains from the plurality of strain tensors with the computer-based system;
determining a dominant tensile strain direction for the digital model from the calculated volume-averaged tensile strains with the computer-based system;
determining a secondary tensile strain direction for the digital model from the calculated volume-averaged tensile strains with the computer-based system;
selecting an orientation for the digital model in a coordinate system based at least in part on the determined dominant tensile strain direction and the determined secondary tensile strain direction;
generating printing instructions based on the oriented digital model with the computer-based system; and
printing the three-dimensional part in a layer-by-layer manner with the additive manufacturing system based on the generated printing instructions.

12. The method of claim 11 , wherein calculating the volume-averaged tensile strains from the plurality of strain tensors comprises calculating weighted volume-averaged tensile strains from the plurality of strain tensors and from one or more weighted values.

13. The method of claim 11 , wherein the strain tensors comprise diagonalized strain tensors.

14. The method of claim 11 , wherein generating the printing instructions comprises:
slicing the oriented digital model into a plurality of sliced layers with the computer-based system, wherein the plurality of sliced layers comprise a first sliced layer;
separating the first sliced layer into a plurality of sub-regions with the computer-based system, wherein the plurality of sub-regions comprise a first sub-region;
calculating, with the computer-based system, local volume-averaged tensile strains for the first sub-region from the strain tensors associated with the first sub-region;
comparing, with the computer-based system, at least one of the calculated local volume-averaged tensile strains for the first sub-region to an elastic limit for a part material used to print the three-dimensional part; and
generating one or more interior fill tool paths for the first sub-region based on the comparison with the computer-based system.

15. The method of claim 14 , wherein the calculated local volume-averaged tensile strains for the first sub-region comprise a highest local volume-averaged tensile strain, and wherein generating the interior fill tool path for the first sub-region comprises aligning at least a portion of the interior fill tool paths with a coordinate direction for the highest local volume-averaged tensile strain.

16. A program stored on a computer storage medium, and configured to be operated by a processor of a computer-based system to perfo

Assignees

• Stratasys Inc

Inventors

• Batchelder J Samuel

Classifications

• G01N3/08

  by applying steady tensile or compressive forces (G01N3/28 takes precedence) · CPC title

• G05B19/4099

  Surface or curve machining, making three-dimensional [3D] objects, e.g. desktop manufacturing · CPC title

• Y02P80/40

  Minimising material used in manufacturing processes · CPC title

• G05B15/02

  electric · CPC title

• G06F2119/18

  Manufacturability analysis or optimisation for manufacturability · CPC title