METHOD TO MONITOR ADDITIVE MANUFACTURING PROCESS FOR DETECTION AND IN-SITU CORRECTION OF DEFECTS

• US 20160236414A1
• Filed: 02/12/2015
• Published: 08/18/2016
• Est. Priority Date: 02/12/2015
• Status: Active Grant

• Current Assignee: Stratasys Incorporated
• Original Assignee: Arevo Inc.
• Inventors: Reese, Riley, Mondesir, Wiener, Bheda, Hemant
• Granted Patent: US 10,421,267 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B29C 64/393 for controlling or regulating additive manufacturing processes
• CPC Class Codes: B33Y 50/02 for controlling or regulating additive manufacturing processes
• CPC Class Codes: G05B 19/4099 Surface or curve machining, making 3D objects, e.g. desktop manufacturing
• CPC Class Codes: G05B 19/41875 characterised by quality surveillance of production
• CPC Class Codes: G05B 2219/32368 Quality control
• CPC Class Codes: G05B 2219/49023 3-D printing, layer of powder, add drops of binder in layer, new powder
• CPC Class Codes: Y02P 80/40 Minimising material used in manufacturing processes
• CPC Class Codes: Y02P 90/02 Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]

Abstract

The present invention provides a system and a method for real time monitoring and identifying defects occurring in a three dimensional object build via an additive manufacturing process. Further, the present invention provides in-situ correction of such defects by a plurality of functional tool heads possessing freedom of motion in arbitrary planes and approach, where the functional tool heads are automatically and independently controlled based on a feedback analysis from the printing process, implementing analyzing techniques. Furthermore, the present invention provides a mechanism for analyzing defected data collected from detection devices and correcting tool path instructions and object model in-situ during construction of a 3D object. A build report is also generated that displays, in 3D space, the structural geometry and inherent properties of a final build object along with the features of corrected and uncorrected defects. Advantageously, the build report helps in improving 3D printing process for subsequent objects.

Claims

1. A system for printing a three dimensional object, said system comprising:

a first engine configured to generate a set of tool path instructions for three dimensional printing of the three dimensional object;

at least one tool head to perform three dimensional printing implementing the tool path instructions;

at least one monitoring device for real time monitoring and detecting one or more defects generated in the three dimensional object;

a controller in operational communication with the at least one monitoring device configured to generate a set of correcting instructions for controlling at least one of the tool heads to correct the defects in the three dimensional object simultaneously while the object is printing; and

the controller configured to communicate with the first engine and instruct the first engine to modify the set of tool path instructions in response to the identified defects and a printed object model, during and after the printing of the object respectively.

2. The system of claim 1, wherein the first engine generates the set of tool path instructions by discretizing a data file into a plurality of segments and further implementing analyzing techniques, such as finite element analysis, where the data file represents inherent properties and parameters of the three dimensional objects.

3. The system of claim 2, wherein the discretization of the data file is based on at least one parameter selected from the group consisting of slicing parameters, object material parameters and object property requirements.

4. The system of claim 1, wherein the plurality of tool heads comprises at least one extruding head for extruding printing material.

5. The system of claim 1, wherein the at least one of tool heads for correcting defects comprises at least one correcting device to implement the set of correcting instructions.

6. The system of claim 1 further comprises a first module configured to generate a build report including the features of the defects, such as location, type, and the like, a list of corrected and uncorrected defects;

and analyze the build report using analyzing techniques, such as finite element analysis to determine final properties of a printed object.

7. The system of claim 1, wherein the tool heads are able to orient in more than one degree of freedom.

8. The system of claim 1 further comprises a data storage module configured to record data for defects such as location, type, dimensionality, contour of the three dimensional object and like.

9. The system of claim 1, wherein the defects detected may include drooping/sagging, insufficient crystallinity, slow solidification, out of tolerance feature, air bubbles, excess polymer, delamination, overhangs, warping, adhesion between printed layers of the object and the like that can result in insufficient mechanical, chemical, or thermal, or electrical properties of the object.

10. The system of claim 1 wherein the at least one monitoring device employs detecting techniques such as visual imaging, IR/Thermal imaging, laser techniques and the like.

11. The system of claim 1, wherein the correcting instructions include cooling, heating, milling, deburring, extruding and the like.

12. The system of claim 1, wherein the tool heads and the first engine may be controlled by a first controller and a second controller respectively.

13. A method for printing a three dimensional object, the method comprising:

inputting a data file defining at least one characteristic of the three dimensional object;

discretizing the data file into a plurality of printable segments to generate a set of tool path instructions, by a first engine;

printing the three dimensional object by a plurality of tool heads, implementing the set of tool path instructions generated by the first engine;

monitoring the printing process in real time by at least one monitoring device for detecting one or more defects produced in the object during the printing;

generating a set of correcting instructions by a controller for correcting the defects, in response to the detection of defect, simultaneously of printing the object; and

modifying and updating the set of tool path instructions by the first engine in response to the detected defects, simultaneously of printing the object.

14. The method of claim 13, wherein the data file, representing object properties and characteristics, such as geometry and inherent properties, is discretized in a plurality of segments based on slicing parameters, object material parameters and property requirements.

15. The method of claim 13, wherein the plurality of tool heads comprise at least one extruding tool head for extruding a building material.

16. The method of claim 13 further comprises:

sending the set of correcting instructions to at least one corrective device for correcting the defects while the object is being printed.

17. The method of claim 16 wherein the corrective device performs a function including cooling, heating, milling, deburring, extruding and the like.

18. The method of claim 13 further comprises:

generating a build report including the features of the defects, such as location, type, and the like, a list of the corrected and uncorrected defects and other defect related information; and

analyzing the build report using analyzing techniques, such as finite element analysis, to determine final properties of a printed object.

19. The method of claim 13 further comprising:

logging real time monitoring data of defects such as location, type, dimensionality, and contour of the three dimensional object and like in a data storage module.

20. The method of claim 13, wherein the defects may include drooping/sagging, insufficient crystallinity, slow solidification, out of tolerance feature, air bubbles, excess polymer, delamination, overhangs, warping, adhesion between printed layers of the object and the like that can result in insufficient mechanical, chemical, or thermal, or electrical properties of the object.

21. The method of claim 13, wherein the monitoring device implements detecting techniques such as visual imaging, IR/thermal imaging, laser techniques and the like.