Methods and apparatus for additive manufacturing along user-specified toolpaths

• US 20160075089A1
• Filed: 09/15/2015
• Published: 03/17/2016
• Est. Priority Date: 09/15/2014
• Status: Active Application

• Current Assignee: Massachusetts Institute of Technology
• Original Assignee: Massachusetts Institute of Technology
• Inventors: Duro Royo, Jorge, Mogas Soldevila, Laia, Oxman, Neri
• Granted Patent: US 10,286,606 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B29C 64/106 using only liquids or viscous materials, e.g. depositing a continuous bead of viscous material
• CPC Class Codes: B29C 64/118 using filamentary material being melted, e.g. fused deposition modelling [FDM]
• CPC Class Codes: B29C 64/393 for controlling or regulating additive manufacturing processes
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 30/00 Apparatus for additive manufacturing; Details thereof or accessories therefor
• CPC Class Codes: B33Y 50/02 for controlling or regulating additive manufacturing processes

Abstract

One or more input/output devices accept user-inputted path instructions that specify a set of multiple deposition paths for an extruder to travel. An actuator actuates motion of the extruder along a trajectory that includes each of the deposition paths and also includes multiple non-deposition paths. For each deposition path: (a) the user-inputted path instructions specify a thickness of an object; and (b) the extruder extrudes the object in accordance with fabrication instructions computed by a computer based at least in part on the thickness. As the extruder moves over the entire trajectory, the extruder extrudes a set of objects, one object per deposition path. The objects adhere to each other to form an integral 3D structure. In some cases, the objects include functionally graded material.

Claims

1. An apparatus comprising:

(a) one or more I/O devices for accepting user-inputted path instructions that specify a set of multiple deposition paths for an extruder to travel; and

(b) an actuator for actuating motion of the extruder along a trajectory that includes each of the deposition paths and also includes multiple non-deposition paths, such that the motion of the extruder along the trajectory includes the extruder moving along a deposition path, then along a non-deposition path, and then along another deposition path;

wherein for each respective path in the set of deposition paths

(i) the user-inputted path instructions specify a thickness of an object, and

(ii) the extruder is configured to extrude the object such that (A) the extruder extrudes the object only while the extruder is moving along the respective path, and (B) the extruder extrudes the object in accordance with fabrication instructions computed by a computer based at least in part on the thickness.

2. The apparatus of claim 1, wherein the fabrication instructions specify (i) a pressure in the extruder or (ii) a parameter that is computed by a computer based at least in part on a pressure in the extruder.

3. The apparatus of claim 1, wherein the fabrication instructions specify (i) an extruder speed or (ii) a parameter that is computed by a computer based at least in part on an extruder speed.

4. The apparatus of claim 1, wherein the thickness is a vertical thickness.

5. The apparatus of claim 1, wherein the thickness is a horizontal thickness.

6. The apparatus of claim 1, wherein the extruder is configured such that:

(a) material that exits a nozzle of the extruder comprises a stream of material; and

(b) material properties of the stream vary at different spatial positions of the stream.

7. The apparatus of claim 1, wherein the extruder includes a nozzle that is configured to extrude a stream of material, such that the stream has an inner core that consists of a first type of material and has an outer sheath that consists of a second type of material, the first and second types of material being different from each other.

8. The apparatus of claim 1, wherein the extruder includes a set of one or more nozzles configured such that:

(a) material that exits the set of one or more nozzles comprises a first stream and a second stream; and

(b) the first stream has different material properties than the second stream.

9. The apparatus of claim 1, wherein the extruder is configured to extrude a set of multiple objects during the motion along the trajectory, one object per deposition path, such that:

(a) each object, respectively, is an object described in clause (i) of claim 1; and

(b) after the set of objects is extruded, each object in the set of objects adheres to at least one other object in the set of objects such that the set of objects together comprises an integral 3D structure.

10. The apparatus of claim 1, wherein the apparatus is not configured to perform sliced layer-by-layer fabrication.

11. A method comprising:

(a) one or more I/O devices accepting user-inputted path instructions that specify a set of multiple deposition paths for an extruder to travel; and

(b) an actuator actuating motion of the extruder along a trajectory that includes each of the deposition paths and also includes multiple non-deposition paths, such that the motion of the extruder along the trajectory includes the extruder moving along a deposition path, then along a non-deposition path, and then along another deposition path;

wherein for each respective path in the set of deposition paths

(i) the user-inputted path instructions specify a height and a width of an object, and

(ii) the extruder extrudes the object such that (A) the extruder extrudes the object only while the extruder is moving along the respective path, and (B) the extruder extrudes the object in accordance with instructions computed by a computer based at least in part on the height and width.

12. The method of claim 11, wherein one or more of the deposition paths are 3D curves.

13. The method of claim 11, wherein:

(a) a set of objects is extruded while the extruder moves along the set of deposition paths, one object per deposition path; and

(b) each object in the set of objects adheres to at least one other object in the set of objects, such that the set of objects together comprise an integral 3D structure.

14. The method of claim 13, wherein:

(a) the deposition paths include a path that is a 3D curve;

(b) the 3D curve includes a first point and a second point, the second point being higher than the first point; and

(c) as the extruder travels along the 3D curve, the extruder extrudes material at both the first and second points, even though the extruder has not completed extrusion at all build points of the integral 3D structure that lie in a horizontal plane that intersects the first point.

15. The method of claim 13, wherein the structure has material properties that vary as a function of spatial position within the structure.

16. The method of claim 13, wherein one or more I/O devices accept input from a user, which input specifies one or more material properties of one or more materials to be extruded during a path in the set of deposition paths.

17. The method of claim 16, wherein the input specifies a concentration for a mixture.

18. The method of claim 13, wherein one or more I/O devices accept input from a user, which input specifies at least one parameter out of a set of parameters that consists of (i) a type of nozzle of the extruder, (ii) nozzle speed, or (iii) a temperature.

19. The method of claim 11, wherein the method does not include steps that collectively comprise sliced layer-by-layer deposition.

20. A system comprising:

(a) one or more I/O devices for accepting user-inputted tool instructions that specify a set of multiple fabrication paths for a tool to travel; and

(b) an actuator for actuating motion of the tool along a trajectory that includes each of the fabrication paths and also includes multiple non-fabrication paths, such that the motion of the tool along the trajectory includes the tool moving along a fabrication path, then along a non-fabrication path, and then along another fabrication path;

wherein for each respective path in the set of fabrication paths

(i) the user-inputted tool instructions specify a thickness of an object, and

(ii) the tool is configured to fabricate the object by additive fabrication such that (A) the tool fabricates the object only while the tool is moving along the respective path, and (B) the tool fabricates the object in accordance with instructions computed by a computer based at least in part on the thickness.