Three-dimensional printing of large objects

1. A method comprising:

providing a first size of a build volume for a three-dimensional printer, the first size including physical dimensions of the build volume;

providing an object model having a second size greater than the first size of the build volume;

separating the object model into a plurality of sub-objects each smaller than the first size of the build volume according to one or more criteria, wherein at least a portion of the plurality of sub-objects are created such that two or more of the plurality of sub-objects can fit collectively into the build volume, with each of the two or more of the plurality of sub-objects in a stable orientation abutting a build platform within the build volume, for combining the two or more of the plurality of sub-objects for fabrication by the three-dimensional printer in a single print;

adding assembly features to the plurality of sub-objects to facilitate a joining of each one of the plurality of sub-objects to at least one other one of the plurality of sub-objects;

adding an identifier to a mating surface of each one of the plurality of sub-objects, the identifier uniquely identifying each sub object to distinguish sub-objects from one another to assist in assembly thereof; and

fabricating a physical instance of each one of the plurality of sub-objects with a three-dimensional printer, thereby providing a plurality of physical sub-objects.

2. The method of claim 1 wherein the one or more criteria includes a build time for each of the plurality of sub-objects, and wherein the plurality of sub-objects are sized to equalize a corresponding build time, thereby facilitating parallel fabrication with a plurality of three-dimensional printers.

3. The method of claim 1 wherein the assembly features include holes.

4. The method of claim 3 wherein the assembly features include complementary holes on adjacent surfaces of two of the plurality of sub-objects, the method further comprising creating a connector model to join the adjacent surfaces of the two of the plurality of sub-objects.

5. The method of claim 4 further comprising fabricating a connector from the connector model with the three-dimensional printer.

6. The method of claim 4 further comprising fabricating the connector from a material having a first melting point lower than a second melting point of a second material used to fabricate the plurality of physical sub-objects.

7. The method of claim 6 further comprising assembling the plurality of physical sub-objects and the connector to form a physical instance of the model.

8. The method of claim 7 further comprising heating the physical instance of the object model to a temperature above the first melting point and below the second melting point.

9. The method of claim 1 wherein the assembly features include one or more registration features to uniquely orient each one of the sub-objects to each other one of the sub-objects when assembled.

10. The method of claim 1 further comprising automatically creating assembly instructions to assemble the plurality of physical sub-objects into a physical instance of the object model.

11. The method of claim 10 , wherein the assembly instructions include written instructions referencing the identifier of each of the plurality of sub-objects.

12. The method of claim 1 wherein the one or more criteria includes an amount of build material required to fabricate each one of the plurality of physical sub-objects.

13. The method of claim 1 wherein the one or more criteria include a size of each one of the plurality of physical sub-objects.

14. The method of claim 1 wherein each one of the plurality of sub-objects is smaller than the build volume by at least an amount including a margin for a placement of a convex registration feature.

15. The method of claim 1 further comprising applying the knapsack problem as a dynamic programming method to arrange the two or more of the plurality of sub-objects in the build volume.

16. The method of claim 1 , wherein, in the stable orientation, each of the two or more of the plurality of sub-objects has a non-curved surface abutting the build platform.

17. A computer program product comprising non-transitory computer executable code embodied in a computer readable medium that, when executing on one or more computing devices, performs the steps of:

providing a first size of a build volume for a three-dimensional printer, the first size including physical dimensions of the build volume;

providing an object model having a second size greater than the size of the build volume;

separating the object model into a plurality of sub-objects each smaller than the first size of the build volume according to one or more criteria, wherein at least a portion of the plurality of sub-objects are created such that two or more of the plurality of sub-objects can fit collectively into the build volume, with each of the two or more of the plurality of sub-objects in a stable orientation abutting a build platform within the build volume, for combining the two or more of the plurality of sub-objects for fabrication by the three-dimensional printer in a single print;

adding assembly features to the plurality of sub-objects to facilitate a joining of each one of the plurality of sub-objects to at least one other one of the plurality of sub-objects;

adding an identifier to a mating surface of each one of the plurality of sub-objects, the identifier uniquely identifying each sub object to distinguish sub-objects from one another to assist in assembly thereof; and

transmitting the plurality of sub-objects to a three-dimensional printer for fabrication of a corresponding plurality of physical sub-objects.

18. The computer program product of claim 17 wherein the one or more criteria includes a build time for each of the plurality of sub-objects, and wherein the plurality of sub-objects are sized to equalize a corresponding build time, thereby facilitating parallel fabrication with a plurality of three-dimensional printers.

19. The method of claim 15 further comprising applying the knapsack problem to select additional objects from among the plurality of sub-objects to combine with the two or more of the plurality of sub-objects for fabrication by the three-dimensional printer in a single print.

20. The computer program product of claim 17 further comprising automatically creating assembly instructions to assemble the plurality of physical sub-objects into a physical instance of the object model, wherein the assembly instructions include written instructions referencing the identifier of each of the plurality of sub-objects.