Continuous pull three-dimensional printing

1. A system comprising:

a robot comprising an articulated robotic arm having a range of movement with at least two degrees of freedom;

a base plate coupled to the articulated robotic arm;

a resin container positioned between a light source and an initial position of the base plate; and

one or more computers and one or more storage devices storing instructions that are operable, when executed by the one or more computers, to cause the one or more computers to perform operations comprising:

obtaining a plurality of layer representations of a plurality of layers of the three-dimensional object to be printed; and

causing the robot and the light source to iteratively perform operations until the plurality of layers of the three-dimensional object have been formed in a sequence, the operations comprising:

emitting, by the light source into the resin container, a light pattern to form a current layer in the sequence of the plurality of layers of the three-dimensional object, the light pattern being defined by a respective layer representation for the current layer, and

pulling, by the articulated robotic arm, the base plate away from the resin container at an angle defined by a shape of a next layer of the plurality of layers that is subsequent to the current layer in the sequence of the plurality of layers of the three-dimensional object.

2. The system of claim 1 , wherein the base plate, the resin container, and the light source are components of a 3D printer, wherein the base plate is arranged above a bottom surface of the resin container, and wherein the light source is arranged below the resin container.

3. The system of claim 1 , wherein the operations comprise:

initially positioning the base plate such that a surface of the base plate contacts resin in the resin container.

4. The system of claim 3 , wherein operating the light source and the base plate to sequentially form the plurality of layers of the three-dimensional object onto the base plate further comprises:

after forming the current layer of the three-dimensional object, forming each subsequent layer of the three-dimensional object including:

(a) moving the base plate upward by a given distance, such that the base plate pulls the current layer of the three-dimensional object upward by the given distance; and

(b) after moving the base plate upward by the given distance, operating the light source to project the light pattern to form the subsequent layer into the resin in the resin container, wherein the projection of the light pattern forms the subsequent layer in a shape of the light pattern at an interface between the current layer of the three-dimensional object and the resin in the resin container.

5. The system of claim 3 , wherein the operations comprise turning off the light source after forming each layer and then turning the light source on in order to form the next layer.

6. The system of claim 1 , wherein the resin in the resin container comprises a first liquid, and wherein the resin container further includes a second liquid having a different viscosity than the resin, such that the second liquid separates from the current layer and provides a substantially planar interface between the first liquid and the second liquid, and wherein each of the plurality of layers of the three-dimensional object is formed at the substantially planar interface between the first liquid and the second liquid.

7. The system of claim 6 , wherein the second liquid comprises glycerin.

8. The system of claim 1 , wherein operating the light source and the base plate to sequentially form the plurality of layers of the three-dimensional object onto the base plate comprises:

using a robotic device attached to the base plate from above to pull the base plate upward and away from the resin container during the formation of the plurality of layers of the three-dimensional object.

9. The system of claim 8 , wherein the articulated robotic arm has six degrees of freedom.

10. One or more non-transitory computer storage media encoded with model data describing a three-dimensional object and encoded with computer program instructions that when executed by a system comprising:

a robot, the robot comprising an articulated robotic arm having a range of movement with at least two degrees of freedom;

a base plate coupled to the articulated robotic arm;

a resin container positioned between a light source and an initial position of the base plate; and

one or more computers and one or more storage devices,

causes the one or more computers to perform operations comprising:

obtaining a plurality of layer representations of a plurality of layers of the three-dimensional object to be printed; and

causing the robot and the light source to iteratively perform operations until the plurality of layers of the three-dimensional object have been formed in a sequence, the operations comprising:

emitting, by the light source into the resin container, a light pattern to form a current layer in the sequence of the plurality of layers of the three-dimensional object, the light pattern being defined by a respective layer representation for the current layer, and

pulling, by the articulated robotic arm, the base plate away from the resin container at an angle defined by a shape of a next layer of the plurality of layers that is subsequent to the current layer in the sequence of the plurality of layers of the three-dimensional object.

11. The one or more non-transitory computer storage media of claim 10 , wherein the base plate, the resin container, and the light source are components of a 3D printer, wherein the base plate is arranged above a bottom surface of the resin container, and wherein the light source is arranged below the resin container.

12. The one or more non-transitory computer storage media of claim 10 , wherein executing the computer program instructions causes the robot to

initially position the base plate such that a surface of the base plate contacts resin in the resin container.

13. The one or more non-transitory computer storage media of claim 10 , wherein operating the light source and the base plate to sequentially form the plurality of layers of the three-dimensional object onto the base plate further comprises:

after forming the current layer of the three-dimensional object, forming each subsequent layer of the three-dimensional object including:

(a) moving the base plate upward by a given distance, such that the base plate pulls the current layer of the three-dimensional object upward by the given distance; and

(b) after moving the base plate upward by the given distance, operating the light source to project the light pattern to form the subsequent layer into the resin in the resin container, wherein the projection of the light pattern forms the subsequent layer in a shape of the light pattern at an interface between the current layer of the three-dimensional object and the resin in the resin container.

14. The medium of claim 12 , wherein the operations comprise turning off the light source after forming each layer and then turning the light source on in order to form the next layer.

15. The medium of claim 10 , wherein the resin in the resin container comprises a first liquid, and wherein the resin container further includes a second liquid having a different viscosity than the resin, such that the second liquid separates from the current layer and provides a substantially planar interface between the first liquid and the second liquid, and wherein each of the plurality of layers of the three-dimensional object is formed at the substantially planar interface between the first liquid and the second liquid.

16. The medium of claim 15 , wherein the second liquid comprises glycerin.

17. The medium of claim 10 , wherein operating the light source and the base plate to sequentially form the plurality of layers of the three-dimensional object onto the base plate comprises:

using a robotic device attached to the base plate from above to pull the base plate upward and away from the resin container during the formation of the plurality of layers of the three-dimensional object.

18. The medium of claim 17 , wherein the articulated robotic arm has six degrees of freedom.

19. A method performed by a system comprising:

a robot, the robot comprising an articulated robotic arm having a range of movement with at least two degrees of freedom;

a base plate coupled to the articulated robotic arm;

a resin container positioned between a light source and an initial position of the base plate; and

one or more computers and one or more storage devices storing instructions,

the method comprising executing, by the one or more computers, the instructions to cause the one or more computers to perform operations comprising:

obtaining a plurality of layer representations of a plurality of layers of the three-dimensional object to be printed; and

causing the robot and the light source to iteratively perform operations until the plurality of layers of the three-dimensional object have been formed in a sequence, the operations comprising:

emitting, by the light source into the resin container, a light pattern to form a current layer in the sequence of the plurality of layers of the three-dimensional object, the light pattern being defined by a respective layer representation for the current layer, and

pulling, by the articulated robotic arm, the base plate away from the resin container at an angle defined by a shape of a next layer of the plurality of layers that is subsequent to the current layer in the sequence of the plurality of layers of the three-dimensional object.

20. The system of claim 1 , wherein iteratively performing the operations causes the system to produce the three-dimensional object in a form that extends beyond a side of the resin container.

21. The system of claim 1 , wherein over the plurality of layers, the articulated robotic arm is configured to pull the base plate away from the resin container in a plurality of different angles.

22. The system of claim 1 , wherein a build volume for the three-dimensional object extends over a side of the resin container.

23. The system of claim 1 , wherein a first layer of the plurality of layers is not parallel to an adjacent layer in the plurality of layers.