IPC分类号：
B29C64/393 | B22F10/80 | B22F12/90 | B28B17/00 | B29C64/10 | B33Y10/00 | B33Y30/00 | B33Y50/02 | G05B19/4099 | G06F30/10 | G06F30/20 | G06T19/00 | G06T19/20 | B22F10/25 | B22F10/28 | B22F10/31 | B22F10/36 | B22F10/366 | B22F10/64 | B22F10/66 | B22F10/85 | B22F12/41 | B28B1/00 | G06F30/00 | G06F113/10 | G06N20/00
当前申请(专利权)人地址：
2710 LAKEVIEW COURT, 94538, FREMONT, CALIFORNIA
发明人：
LAPPAS, TASSO | LEVIN, EVGENI | BULLER, BENYAMIN
代理机构：
FOLEY & LARDNER LLP
摘要：
The present disclosure provides three-dimensional (3D) methods, apparatuses, software (e.g., non-transitory computer readable medium), and systems for the formation of at least one desired 3D object; comprising use of a geometric model, a physics based model, one or more markers, one or more modes, or any combination thereof. The disclosure provides reduction of deformation that may be caused by the forming process of the 3D object.
技术问题语段：
The manufacturing processes can affect the shape of the three-dimensional objects in unintended ways.
权利要求：
1. An apparatus for printing a three-dimensional (3D) object, the apparatus comprising at least one controller configured to:
(a) couple to a power source and operatively couple to a 3D printer;
(b) direct the 3D printer to print a test object using a first set of printing instructions generated at least in part by employing a simulation of a physics model simulating the printing of the 3D object by the 3D printer, the physics model employing a first mode estimating alteration in the 3D object printed as a result of the printing, the first mode being of a plurality of modes, each of the plurality of modes representing a plausible alteration of the 3D object (A) during the printing and/or (B) as a result of the printing, the physics model further employing (I) a geometric model of the 3D object and (II) a material property of the 3D object;
(c) compare, or direct comparison, between (i) a simulated test object generated at least in part by using the physics model and (ii) an image of the test object printed using the printing instructions, to generate a comparison;
(d) use, or direct use of, the comparison to adjust the physics model at least in part by choosing a second mode of the plurality of modes that best fits the test object printed, to generate an adjusted physics model; and
(e) direct the 3D printer to print the 3D object using a second set of printing instructions generated at least in part by employing the adjusted physics model.
2. The apparatus of claim 1, wherein the at least one controller is configured to direct iteratively repeating (b), (c), (d) and (e), until one or more dimensions of the test object corresponds to an acceptable dimensional accuracy range relating to a requested 3D object.
3. The apparatus of claim 1, wherein the test object comprises markers, wherein the at least one controller is configured to (i) operatively couple with at least one sensor, (ii) direct the at least one sensor to sense one or more physical markers and generate sensing data, and (iii) use, or direct usage of, the sensing data to choose the second mode that best fits the test object printed.
4. The apparatus of claim 3, wherein the at least one controller is configured to, during the printing, (ii) direct the at least one sensor to sense one or more physical markers and generate sensing data, and (iii) use, or direct usage of, the sensing data to choose the second mode that best fits the test object printed.
5. The apparatus of claim 1, wherein the at least one controller is configured to use, or directing use of, the comparison to adjust the physics model at least in part by employing the first mode corresponding to a predicted deformation mode of the 3D object.
6. The apparatus of claim 5, wherein the at least one controller is configured to use, or directing use of, the comparison to adjust the physics model at least in part by employing the first mode corresponding to a predicted elastic deformation mode of the 3D object.
7. The apparatus of claim 1, wherein the at least one controller is configured to use, or directing use of, the comparison to adjust the physics model at least in part by using a computational learning scheme.
8. The apparatus of claim 5, wherein the at least one controller is configured to use, or directing use of, the comparison to adjust the physics model at least in part by using a computational learning scheme comprising an inelastic response manifested in the 3D object.
9. The apparatus of claim 1, wherein the at least one controller is configured to print the 3D object such that the 3D object deviates from a requested 3D object by (a) at most 100 micrometers and (b) a fundamental length scale of the 3D object divided by 2500.
10. The apparatus of claim 1, wherein the at least one controller is configured to adjust, or direct adjustment, of the physics model iteratively.
11. The apparatus of claim 1, wherein the at least one controller is configured to repeat (a), (b) and (c) iteratively.
12. The apparatus of claim 11, wherein the at least one controller is configured to repeat (a), (b) and (c) iteratively until one or more dimensions of the test object corresponds to an acceptable dimensional accuracy range relating to the 3D object requested, the acceptable dimensional accuracy range being according to (i) an intended purpose of the 3D object and/or (ii) an industrial standard.
13. The apparatus of claim 1, wherein the at least one controller is configured to direct the 3D printer to print the test object using a first set of printing instructions generated at least in part by employing the physics model comprising (a) a thermo-mechanical analysis, (b) the material property of the 3D object, and (c) at least one characteristic of an energy beam used for the printing.
14. The apparatus of claim 1, wherein the at least one controller is configured to direct the 3D printer to print the test object using a first set of printing instructions generated at least in part by employing the physics model comprising continuum mechanics.
15. The apparatus of claim 1, wherein the at least one controller is configured to direct the 3D printer to (a) print the test object from a powder bed and (b) print the 3D object from the powder bed.
16. The apparatus of claim 1, wherein the at least one controller is configured to direct the 3D printer to (a) print the test object using an energy beam and (b) print the 3D object using the energy beam.
17. The apparatus of claim 1, wherein the at least one controller is configured to direct the 3D printer to (a) print the test object from a material and (b) print the 3D object from the material comprising elemental metal, metal alloy, ceramic, or an allotrope of elemental carbon.
18. The apparatus of claim 17, wherein the at least one controller is configured to direct the 3D printer to (a) print the test object at an atmosphere and (b) print the 3D object at the atmosphere comprising (i) oxygen or (ii) water vapor.
19. Non-transitory computer readable program instructions that, when read by one or more processors operatively coupled to the 3D printer configured for the printing, cause the one or more processors to execute one or more operations comprising executing the printing to print the 3D object of claim 1, the program instructions being stored on at least one non-transitory computer readable medium.
20. A method of printing the 3D object, the method comprising (a) providing the apparatus of claim 1, and (b) using the apparatus to print the 3D object.
背景技术：
[0002]Three-dimensional objects can be made using manufacturing processes. The manufacturing processes can affect the shape of the three-dimensional objects in unintended ways. Examples of manufacturing processes for forming three-dimensional objects include three-dimensional (3D) printing.
[0003]Three-dimensional (3D) printing (e.g., additive manufacturing) is a process for making a three-dimensional object (e.g., of any shape) from a design. The design may be in the form of a data source such as an electronic data source, or may be in the form of a hard copy. The hard copy may be a two-dimensional representation of a 3D object. The data source may be an electronic 3D model. 3D printing may be accomplished through, for example, an additive process in which successive layers of material are laid down one on top of another. This process may be controlled (e.g., computer controlled, manually controlled, or both). A 3D printer can be an industrial robot.
[0004]3D printing can generate custom parts. A variety of materials can be used in a 3D printing process including elemental metal, metal alloy, ceramic, elemental carbon, or polymeric material. In some 3D printing processes (e.g., additive manufacturing), a first layer of hardened material is formed (e.g., by welding powder), and thereafter successive layers of hardened material are added one by one, wherein each new layer of hardened material is added on a pre-formed layer of hardened material, until the entire designed three-dimensional structure (3D object) is layer-wise materialized.
[0005]3D models may be created with a computer aided design package, via 3D scanner, or manually. The manual modeling process of preparing geometric data for 3D computer graphics may be similar to plastic arts, such as sculpting or animating. 3D scanning is a process of analyzing and collecting digital data on the shape and appearance of a real object (e.g., real-life object). Based on this data, 3D models of the scanned object can be produced.
[0006]A number of 3D printing processes are currently available. They may differ in the manner layers are deposited to create the materialized 3D structure (e.g., hardened 3D structure). They may vary in the material or materials that are used to materialize the designed 3D object. Some methods melt, sinter, or soften material to produce the layers that form the 3D object. Examples for 3D printing methods include selective laser melting (SLM), selective laser sintering (SLS), direct metal laser sintering (DMLS) or fused deposition modeling (FDM). Other methods cure liquid materials using different technologies such as stereo lithography (SLA). In the method of laminated object manufacturing (LOM), thin layers (made inter alia of paper, polymer, or metal) are cut to shape and joined together.
[0007]Due to the manufacturing (e.g., printing) procedures and/or materials chosen, some 3D objects may deform during and/or after their generation. At times it is desirable to print a 3D object that has a reduced level of deformation. It may be desirable to form (e.g., print) a 3D object that is substantially similar to the requested 3D object (e.g., by a client). It may be desirable to develop a methodology to monitor the forming (e.g., printing) of the 3D objects.
发明内容：
[0008]In some embodiments, the present disclosure delineates methods, systems, apparatuses, and software that allow modeling and forming of 3D objects with a reduced amount of design constraints (e.g., no design constraints). The present disclosure delineates methods, systems, apparatuses, and software that allow materialization of 3D object and models thereof. Described herein is also a way of tracking of 3D object formation (e.g., 3D printing) that may be of assistance in reducing and/or controlling deformation that occur during formation of a (physical) 3D object.
[0009]In an aspect is a method for monitoring a three-dimensional (3D) printing process that comprises (a) generating a prior marked model (e.g., first marked model) of a requested 3D object by inserting one or more markers in a model design of the requested 3D object; (b) forming a prior marked 3D object based on the prior marked model of the requested 3D object; (c) calculating a deviation by comparing between: the one or more markers in the prior marked model of the requested 3D object in (a), and the prior marked 3D object in (b); and (d) monitoring the 3D printing process based on the calculating, which one or more markers are structural.
[0010]In some embodiments, the one or more markers that are structural comprise depression, protrusion, or deletion as compared to the requested 3D object. In some embodiments, the deletion is a hole. In some embodiments, forming comprises using a printing instruction to form the prior marked 3D object (e.g., first marked 3D object). In some embodiments, the one or more markers are small such that the printing instruction to form the prior marked 3D object is substantially similar to a printing instruction to form the requested 3D object. In some embodiments, substantially is relative to the intended purpose of the 3D object. In some embodiments, monitoring comprises adjusting the 3D printing process based on the calculating. In some embodiments, adjusting comprises: (i) generating a subsequent marked model (e.g., second marked model) of a requested 3D object by adjusting the prior marked model based on the calculating in operation (c); (ii) forming a subsequent marked 3D object (e.g., second marked 3D object) based on the subsequent marked model of the requested 3D object; (iii) calculating a deviation by comparing between: the one or more markers of the subsequent marked model of the requested 3D object in (i), and the subsequent marked 3D object in (ii); or (iv) repeating steps (i) to (iii) based on a deviation value. In some embodiments, adjusting in (i) is relative to the intended purpose of the requested 3D object. In some embodiments, adjusting in (i) comprises corrective adjustment. In some embodiments, adjusting in (i) comprises geometric adjustment. In some embodiments, adjusting in (i) comprises structural adjustment. In some embodiments, adjusting in (i) results in reducing the deviation value. In some embodiments, the deviation value is (e.g., substantially) based on the intended purpose of the requested 3D object, and the repeating in (iv) occurs. In some embodiments, the deviation value is insubstantial and the repeating in (iv) does not occur. In some embodiments, the method further comprises forming the requested 3D object based on the subsequent marked model of the requested 3D object. Insubstantial can be relative to the intended purpose of the requested 3D object. In some embodiments, the deviation value is insubstantial. In some embodiments, the method further comprises forming the requested 3D object based on the prior marked model of the requested 3D object. In some embodiments, adjusting results in a subsequent marked 3D object comprises less auxiliary support as compared to the prior marked 3D object. In some embodiments, less is a fewer number of auxiliary support structures. In some embodiments, less is smaller contact area between the auxiliary support and the subsequent marked 3D object. In some embodiments, the method further comprises using the calculating in a simulation. In some embodiments, the simulation comprises a simulation of the 3D printing process. In some embodiments, the simulation comprises a simulation of the requested 3D object. In some embodiments, the simulation comprises a simulation of the marked model of the requested 3D object. In some embodiments, the simulation comprises the 3D printing directions. In some embodiments, the simulation comprises the requested 3D object. In some embodiments, the simulation comprises the marked model of the requested 3D object. In some embodiments, the simulation comprises a learning algorithm. In some embodiments, comparing comprises measuring a fundamental length scale, shape, or volume of at least one of the one or more markers of the prior marked 3D object. In some embodiments, comparing comprises measuring a fundamental length scale, shape, or volume of at least one of the one or more markers of the prior marked 3D object and/or of a subsequent marked 3D object (e.g., subsequent to the prior marked 3D object). In some embodiments, comparing comprises metrologically measuring the one or more markers of the prior marked 3D object. In some embodiments, comparing comprises metrologically measuring the one or more markers of the prior marked 3D object and/or of the subsequent marked 3D object. In some embodiments, metrologically comprises measuring a distance between at least two markers. In some embodiments, measuring a distance between at least two markers comprises measuring a distance between the center of the at least two markers. In some embodiments, measuring a distance between at least two markers comprises measuring a distance between the circumference of the at least two markers. The prior can be relative to the subsequent. The prior can be first. The subsequent can be second, third, fourth, etc.
[0011]Another aspect of the present disclosure provides a computer system comprising one or more computer processors and a non-transitory computer-readable medium coupled thereto. The non-transitory computer-readable medium comprises machine-executable code that, upon execution by the one or more computer processors, implements any of the methods disclosed herein.
[0012]In another aspect, a system for monitoring a 3D printing process, comprises: a first processor that is configured to generate a prior marked model of a requested 3D object by inserting one or more markers in a model design of the requested 3D object to form a marked 3D object; a 3D printer that is configured to print a prior marked 3D object based on the prior marked model of the requested 3D object; a second processor that is configured to calculate a deviation by comparing between: (i) the one or more markers in the prior marked model of the requested 3D object, and (ii) the prior marked 3D object; and (d) a third processor that is configured to monitor the 3D printing process based on the deviation, which one or more markers are structural, wherein at least two of the first processor, second processor, third processor, and 3D printer are operatively coupled.
[0013]In some embodiments, the at least two of the first processor, second processor, and third processor are the same processor. In some embodiments, the 3D printer comprises an energy beam (e.g., laser or electron-beam). In some embodiments, the 3D printer comprises a layer dispensing mechanism. In some embodiments, the 3D printer is configured to accommodate a material bed. In some embodiments, the 3D printing comprises a platform that is configured to support the 3D object. In some embodiments, the 3D printer is an additive 3D printer. In some embodiments, the system further comprises at least one controller that is operatively coupled to at least one of the 3D printer, first processor, second processor, and third processor are the same processor. In some embodiments, the system further comprises a sensor that senses at least one characteristic of the one or more markers. In some embodiments, the sensor comprises a temperature or metrology (e.g., height) sensor. In some embodiments, the characteristic is a metrological characteristic.
[0014]In another aspect, an apparatus for printing one or more 3D objects comprises at least one controller that is programmed to direct at least one mechanism used in a 3D printing methodology to implement (e.g., effectuate) any of the method disclosed herein, wherein one or more of the at least one controller is operatively coupled to the mechanism.
[0015]In another aspect, at least one controller comprises a plurality of controllers and wherein at least two of operations (e.g., at least two of (a), (b), (c) operations) are directed by the same controller. In some embodiments, at least one controller comprises a plurality of controllers and wherein at least two operations (e.g., at least two of (a), (b), (c) operations) are directed by different controllers. In some embodiments, the at least two operations may be of a method, a software, and/or operations programed in a control scheme.
[0016]In another aspect, an apparatus for monitoring a 3D printing process, comprises: (a) a first controller that is programmed to direct generating a prior marked model of a requested 3D object by inserting one or more markers in a model design of the requested 3D object; (b) a second controller that is programmed to direct forming a prior marked 3D object based on the prior marked model of the requested 3D object; (c) a third controller that is programmed to direct calculating a deviation by comparing between: the one or more markers in the prior marked model of the requested 3D object in (a), and the prior marked 3D object in (b); and (d) a fourth controller that is programmed to direct monitoring the 3D printing process based on the deviation, which one or more markers are structural, wherein at least two of the first processor, second processor, third processor, and 3D printer are operatively coupled.
[0017]In some embodiments, the at least two of the first controller, second controller, third controller, and fourth controller are the same controller. In some embodiments, the at least two of the first controller, second controller, third controller, and fourth controller are different controllers. In some embodiments, the at least one of the first controller, second controller, third controller, and fourth controller comprises a proportional-integral-derivative (PID) controller. In some embodiments, the at least one of the first controller, second controller, third controller, and fourth controller comprises a feedback loop. In some embodiments, the at least one of the first controller, second controller, third controller, and fourth controller comprises a feed forward loop. In some embodiments, the at least one of the first controller, second controller, third controller, and fourth controller comprises a closed loop control (e.g., based on a sensor signal, e.g., a temperature signal, and/or a power signal). In some embodiments, the at least one of the first controller, second controller, third controller, and fourth controller comprises an open loop control. In some embodiments, the at least one of the first controller, second controller, third controller, and fourth controller comprises a real-time controller. In some embodiments, the at least one of the first controller, second controller, third controller, and fourth controller comprises a temperature controller (e.g., controlling the melt pool temperature, e.g., in real time). In some embodiments, the at least one of the first controller, second controller, third controller, and fourth controller comprises a metrology controller (e.g., mapping the exposed surface of a material bed and/or 3D object, e.g., in real time). In some embodiments, the at least one of the first controller, second controller, third controller, and fourth controller comprises a power controller (e.g., controlling the power of the energy source and/or power density of the energy beam, e.g., in real time).
[0018]In another aspect, a computer software product comprises: (a) a first non-transitory computer-readable medium in which program instructions are stored, which instructions, when read by a first computer, cause the first computer to generate a prior marked model of a requested 3D object by inserting one or more markers in a model design of the requested 3D object, wherein the prior marked model of the requested 3D object is utilized to form a prior marked 3D object based on the prior marked model of the requested 3D object; and (b) a second non-transitory computer-readable medium in which program instructions are stored, which instructions, when read by a second computer, cause the second computer to calculate a deviation by comparing between: the one or more markers in the prior marked model of the requested 3D object in (a), and the prior marked 3D object in (b), wherein the deviation is used to control (e.g., adjust) the 3D printing process, and wherein one or more markers are structural.
[0019]In some embodiments, the first non-transitory computer-readable medium and the second non-transitory computer-readable medium are the same non-transitory computer-readable medium. In some embodiments, the first non-transitory computer-readable medium and the second non-transitory computer-readable medium are different. In some embodiments, the first computer and the second computer are the same. In some embodiments, the first computer and the second computer are different.
[0020]In another aspect, a method for forming a three-dimensional object comprises comparing one or more model markers with one or more physical markers, which one or more model markers are disposed on and/or in a geometric model of the three-dimensional object, wherein the one or more physical markers are disposed on and/or in a test object that is formed by employing the geometric model, which one or more physical markers correspond to the one or more model markers.
[0021]In another aspect (e.g., that can be related to the one above), a method for forming a three-dimensional object comprises: (a) (optionally) forming a test object using a geometric model of the three-dimensional object, and one or more model markers disposed on and/or in the geometric model of the three-dimensional object, the test object having one or more physical markers that correspond to the one or more model markers; and (b) comparing (e.g., locations, dimensions, and/or material properties of) the one or more model markers with (e.g., locations, dimensions, and/or material properties of) the one or more physical markers.
[0022]In some embodiments, the comparing is of location, shape, volume, fundamental length scale, and/or a material property. In some embodiments, the method further comprises operation (c) generating a corrected geometric model using the comparing in operation (b). In some embodiments, the method further comprises operation (d) forming the three-dimensional object using the corrected geometric model. In some embodiments, the method further comprises repeating operations (a), (b) and (c) using iteratively adjusted geometric models and a plurality of test objects until the locations of the one or more model markers (e.g., substantially) converge with the locations of the one or more physical markers. In some embodiments, a predefined location threshold of the physical markers comprises a vicinity of the one or more physical markers and the location of the one or more physical markers. In some embodiments, the locations of the one or more model markers converge within the predefined location threshold of the one or more physical markers. In some embodiments, the method further comprises generating a physics model that employs an estimated change of at least one characteristic of the three-dimensional object resulting from the forming. In some embodiments, the method further comprises forming a simulated object employing the physics model. In some embodiments, the method further comprises comparing the simulated object with the test object. In some embodiments, comparing the simulated object with the test object comprises comparing one or more dimensions of the simulated object with respective one or more dimensions of the test object. In some embodiments, the method further comprises generating a corrected geometric model employing comparing the simulated object with the test object. In some embodiments, the method further comprises forming the three-dimensional object while employing the corrected geometric model. In some embodiments, the at least one characteristic of the three-dimensional object comprises a material property of the three-dimensional object. In some embodiments, the at least one characteristic of the three-dimensional object comprises a geometry of the three-dimensional object. In some embodiments, the physics model employs an estimated thermally induced change in the three-dimensional object present upon formation of the three-dimensional object. In some embodiments, the estimated thermally induced change comprises an estimated volumetric change in at least a portion of the three-dimensional object. In some embodiments, the estimated thermally induced change comprises an estimated expansion or an estimated contraction in at least a portion of the three-dimensional object. In some embodiments, the estimated thermally induced change comprises an estimated change in a microstructure of at least a portion of the three-dimensional object. In some embodiments, the estimated change in the microstructure comprises an estimated change in a crystal structure. In some embodiments, the estimated change in the microstructure comprises an estimated change in a metallurgical microstructure. In some embodiments, the physics model employs an estimated thermo-mechanical change in the three-dimensional object present upon formation of the three-dimensional object. In some embodiments, the estimated thermo-mechanical change comprises an estimated thermoplastic or thermo-elastic change. In some embodiments, the estimated thermo-mechanical change comprises an estimated thermo-mechanical deformation. In some embodiments, the physics model employs an estimated mechanical alteration in the three-dimensional object present upon formation of the three-dimensional object. In some embodiments, the estimated mechanical alteration comprises an estimated inelastic or elastic change. In some embodiments, inelastic change comprises plastic change. In some embodiments, the estimated mechanical alteration comprises mechanical deformation. In some embodiments, the estimated mechanical alteration comprises a set of modes. In some embodiments, the method further comprises generating a physics model employing an estimated alteration in the three-dimensional object present upon formation of the three-dimensional object. In some embodiments, the estimated alteration is a deformation. In some embodiments, the method further comprises comparing a simulated object with the test object. In some embodiments, the simulated object is generated using the physics model. In some embodiments, the method further comprises adding the one or more model markers to the geometric model. In some embodiments, the method further comprises removing the one or more model markers from the geometric model. In some embodiments, the one or more model markers comprises an induced change to the three-dimensional object. In some embodiments, the one or more model markers comprises a protrusion, a depression, or a deletion. In some embodiments, the one or more model markers comprise tessellation borders, or point clouds. In some embodiments, the one or more physical markers comprise a pore, dislocation, crack, microstructure, crystal structure, or a metallurgical morphology. In some embodiments, the one or more model markers are positioned on a surface and/or within a volume of the geometric model. In some embodiments, (b) comprises performing a data analysis. In some embodiments, the data analysis comprises at least one of: linear regression, least squares fit, Gaussian process regression, kernel regression, nonparametric multiplicative regression (NPMR), regression trees, local regression, semiparametric regression, isotonic regression, multivariate adaptive regression splines (MARS), logistic regression, robust regression, polynomial regression, stepwise regression, ridge regression, lasso regression, elasticnet regression, principal component analysis (PCA), singular value decomposition, fuzzy measure theory, Borel measure, Harr measure, risk-neutral measure, Lebesgue measure, group method of data handling (GMDH), Naive Bayes classifiers, k-nearest neighbors algorithm (k-NN), support vector machines (SVMs), neural networks, support vector machines, classification and regression trees (CART), random forest, gradient boosting, or generalized linear model (GLM) technique. In some embodiments, the forming the three-dimensional object comprises printing the three-dimensional object using three-dimensional printing. In some embodiments, the forming the three-dimensional object comprises additively or substantively forming the three-dimensional object. In some embodiments, the forming the three-dimensional object comprises extrusion, molding, or sculpting.
[0023]In another aspect, a system for forming a three-dimensional object, the system comprising one or more controllers is/are configured to direct comparing one or more model markers with one or more physical markers, which one or more model markers are disposed on and/or in a geometric model of the three-dimensional object, wherein the one or more physical markers are disposed on and/or in a test object that is formed by employing the geometric model, which one or more physical markers correspond to the one or more model markers.
[0024]In another aspect (e.g., that can be related to the one above), a system for forming a three-dimensional object, the system comprising: one or more controllers that are collectively or separately configured to direct: (a) (optionally) forming a test object using a geometric model of the three-dimensional object, and one or more model markers disposed on and/or in the geometric model of the three-dimensional object, the test object having one or more physical markers that correspond to the one or more model markers; and (b) comparing (e.g., locations, dimensions, and/or material properties of) the one or more model markers with (e.g., locations, dimensions, and/or material properties of) the one or more physical markers.
[0025]In some embodiments, the comparing is of location, shape, volume, fundamental length scale, and/or a material property. In some embodiments, at least one of the one or more controllers comprises a feed forward and/or feedback control loop. In some embodiments, at least one of the one or more controllers comprises a closed loop and/or open loop control scheme. In some embodiments, forming the three-dimensional object comprises printing the three-dimensional object using three-dimensional printing. In some embodiments, forming the three-dimensional object comprises additively or substantively forming the three-dimensional object. In some embodiments, forming the three-dimensional object comprises extrusion, molding, or sculpting. In some embodiments, the one or more controllers is further configured to direct operation (c) an energy beam to transform a pre-transformed material into a transformed material to form the three-dimensional object. In some embodiments, operation (c) is during (a). In some embodiments, at least two of the one or more controllers directing operation (a) to operation (c) are different controllers. In some embodiments, at least two of the one or more controllers directing operation (a) to operation (c) are the same controller. In some embodiments, the one or more controllers is configured to direct at least one energy source to generate and direct at least one energy beam at a pre-transformed material. In some embodiments, the one or more controllers is further configured to direct operation (d) a platform to vertically translate, which platform is configured to support the three-dimensional object. In some embodiments, operation (d) is during (a). In some embodiments, at least two of the one or more controllers directing operation (a) to operation (d) are different controllers. In some embodiments, at least two of the one or more controllers directing operation (a) to operation (d) are the same controller. In some embodiments, the system further comprises a chamber configured to enclose at least a portion of the three-dimensional object during its formation. In some embodiments, the one or more controllers is configured to monitor and/or control a progress of formation of the three-dimensional object within the chamber. In some embodiments, the system further comprises at least one sensor configured to sense the one or more physical markers. In some embodiments, the one or more controllers is configured to (i) control sensing and/or (ii) use sensing data, of the one or more physical markers. In some embodiments, the one or more controllers is configured to (i) control sensing and/or (ii) use sensing data, of the one or more physical markers during forming of the three-dimensional object. In some embodiments, the one or more controllers is configured to (i) control sensing and/or (ii) use sensing data, of the one or more physical markers after forming of the three-dimensional object. In some embodiments, the system further comprises at least one detector that is operationally coupled to the one or more controllers, the at least one detector configured to detect as least one characteristic of the forming. In some embodiments, the one or more controllers is configured to control the at least one detector and/or control one or more process parameters present upon a detection by the at least one detector. In some embodiments, the at least one detector is configured to detect a temperature during the forming of the three-dimensional object. In some embodiments, the one or more controllers is configured to control (e.g., monitor) detection of the temperature. In some embodiments, the temperature corresponds to a temperature of the three-dimensional object. In some embodiments, the temperature corresponds to a temperature of a vicinity of the three-dimensional object. In some embodiments, the vicinity is in a material bed that is configured to accommodate the three-dimensional object. In some embodiments, the temperature corresponds to a temperature of an atmosphere surrounding the three-dimensional object. In some embodiments, the at least one detector is configured to detect at least one of cleanliness, pressure, humidity, or oxygen level of an atmosphere surrounding the three-dimensional object during the forming. In some embodiments, detecting a cleanliness comprises detecting a number of particles within at least a processing cone of the atmosphere. In some embodiments, the one or more controllers comprise at least two controllers. In some embodiments, the one or more controllers is one controller. In some embodiments, the one or more controllers is configured to direct operation (e) generating a corrected geometric model using the comparing in operation (b). In some embodiments, the one or more controllers is configured to direct operation (f) forming the three-dimensional object using the corrected geometric model. In some embodiments, the one or more controllers is configured to direct repeating operations (a), (b) and (e) using iteratively adjusted geometric models and a plurality of test objects, until locations of the one or more model markers (e.g., substantially) converge with locations of the one or more physical markers. In some embodiments, the one or more controllers is configured to direct generating a physics model that employs an estimated change of at least one characteristic of the three-dimensional object resulting from the forming. In some embodiments, the system further comprises forming a simulated object employing the physics model. In some embodiments, the physics model comprises calculating a plurality of modes, each of the plurality of modes having an associated energy, each of the plurality of modes representing a plausible alteration component of the three-dimensional object during a printing operation.
[0026]In another aspect, a computer software product comprising at least one non-transitory computer-readable medium in which program instructions are stored, which program instructions, when read by at least one computer, cause the at least one computer to direct comparing one or more model markers with one or more physical markers, which one or more model markers are disposed on and/or in a geometric model of the three-dimensional object, wherein the one or more physical markers are disposed on and/or in a test object that is formed by employing the geometric model, which one or more physical markers correspond to the one or more model markers.
[0027]In another aspect (e.g., that can be related to the one above), a computer software product comprising at least one non-transitory computer-readable medium in which program instructions are stored, which program instructions, when read by at least one computer, cause the at least one computer to direct comparing (i) (e.g., locations, dimensions, and/or material properties of) one or more model markers of a geometric model that is used to form a three-dimensional test object with (ii) (e.g., locations, dimensions, and/or material properties of) one or more physical markers of a formed three-dimensional test object, wherein the one or more model markers are disposed on and/or in the geometric model of the test three-dimensional object; and the one or more physical markers correspond to the one or more model markers.
[0028]In some embodiments, the comparing is of location, shape, volume, fundamental length scale, and/or a material property. In some embodiments, the (e.g., successful) test object is a requested three-dimensional object. In some embodiments, the comparing is operation (a), and wherein the program instructions further cause the at least one computer to direct operation (b) forming the three-dimensional test object using the geometric model of the three-dimensional test object. In some embodiments, the forming in (b) further comprises the one or more model markers. In some embodiments, a non-transitory computer-readable medium causes a computer to direct operation (a) and operation (b). In some embodiments, a non-transitory computer-readable medium cause a first computer to direct operation (a) and a second computer to direct operation (b). In some embodiments, a first non-transitory computer-readable medium causes a computer to direct operation (a) and a second non-transitory computer-readable medium cause the computer to direct operation (b). In some embodiments, a first non-transitory computer-readable medium cause a first computer to direct operation (a) and a second non-transitory computer-readable medium cause a second computer to direct operation (b). In some embodiments, the program instructions cause the at least one computer to direct a feed forward and/or feedback control loop. In some embodiments, the program instructions cause the at least one computer to direct a closed loop and/or open loop control scheme. In some embodiments, operation (b) comprises printing the three-dimensional test object. In some embodiments, operation (b) comprises additively or substantively forming the three-dimensional test object. In some embodiments, operation (b) comprises extrusion, molding, or sculpting the three-dimensional test object. In some embodiments, the comparing is operation (a), wherein the program instructions further cause the at least one computer to direct: operation (c) forming a requested object while employing the comparing. In some embodiments, operation (c) comprises directing an energy beam to transform a pre-transformed material into a transformed material. In some embodiments, a non-transitory computer-readable medium cause a computer to direct at least two of operations (a), (b) and (c). In some embodiments, a non-transitory computer-readable medium cause each a different computer to direct at least two of operations (a), (b) and (c). In some embodiments, different non-transitory computer-readable mediums cause each a different computer to direct at least two of operations (a), (b) and (c). In some embodiments, the prog
具体实施方式：
[0123]The figures and components therein may not be drawn to scale. Various components of the figures described herein may not be drawn to scale.
DETAILED DESCRIPTION
[0124]While various embodiments of the invention have been shown and described herein, it will be obvious to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions may occur to those skilled in the art without departing from the invention. It should be understood that various alternatives to the embodiments of the invention described herein might be employed.
[0125]The process of generating a three-dimensional object (e.g., three-dimensional printing processes) may cause certain alterations (e.g., deformations) to occur in the three-dimensional (3D) object. The alterations may be structural alterations in the overall shape of at least a portion of the 3D object and/or in the microstructure of at least a portion of the 3D object. For example, the alterations can cause geometric dimensions (shape) of the 3D object to vary from a requested geometric dimension (e.g., and shape). An alteration can occur due to, warping (e.g., bending or twisting) of the 3D object. An alteration can occur due to thermal expansion of the 3D object, issues related to tool offset, and other mechanisms related to the generation process. The tool can be a 3D printer, a mold, an extrusion mechanism, a welding mechanism, or any other tool related to the process of generating the 3D object. Methods, software, apparatus, and systems described herein can be used to quantify an alteration caused by the generating process, predict the alteration induced by the generating process, create one or more computer-based models that compensate for the alteration (e.g., deformation), generate 3D objects having improved dimensional accuracy, or any combination thereof.
[0126]Terms such as “a”, “an” and “the” are not intended to refer to only a singular entity, but include the general class of which a specific example may be used for illustration. The terminology herein is used to describe specific embodiments of the invention(s), but their usage does not delimit the invention(s).
[0127]When ranges are mentioned, the ranges are meant to be inclusive, unless otherwise specified. For example, a range between value 1 and value 2 is meant to be inclusive and include value 1 and value 2. The inclusive range will span any value from about value 1 to about value 2. The term “adjacent” or “adjacent to,” as used herein, includes ‘next to’, ‘adjoining’, ‘in contact with’, and ‘in proximity to.’ When “and/or” is used in a sentence such as X and/or Y, the phrase means: X, Y, or any combination thereof.
[0128]As used herein, the term “operatively coupled” or “operatively connected” refers to a first mechanism that is coupled (or connected) to a second mechanism to allow the intended operation of the second and/or first mechanism.
[0129]As used herein, the terms “object”, “3D part”, and “3D object” may be used interchangeably, unless otherwise indicated.
[0130]Fundamental length scale (abbreviated herein as “FLS”) can be refer herein as to any suitable scale (e.g., dimension) of an object. For example, a FLS of an object may comprise a length, a width, a height, a diameter, a spherical equivalent diameter, or a diameter of a bounding sphere. In some cases, FLS may refer to an area, a volume, a shape, or a density.
[0131]As used herein, the term “based on” is not meant to be restrictive. That is, “based on” does not necessarily mean “exclusively based on” or “primarily based on”. For example, “based on” can be synonymous to “using” or “considering.”
[0132]In some embodiments, a 3D object is marked with one or more markers. A marked three-dimensional (3D) object may comprise the one or more markers. The markers can be embedded on at least one surface and/or interior portion of a desired 3D object. The markers may comprise a depression (e.g., embossing, degradation, or intrusion), protrusion (e.g., extrusion, swelling, elevation, or projection), or deletion (e.g., omission, or hole) in at least one portion of the desired 3D object. The marker can correspond to a feature (e.g., two dimensional and/or three dimensional) that is located in pre-determined locations of a 3D object. In some embodiments, the markers reside on a surface of the 3D object. In some embodiments, the markers reside within a volume of the 3D object. In some embodiments, the markers are discrete features. The markers may decorate the 3D object. The markers may be a part of the 3D object geometry (e.g., a tessellation border, or an edge of the 3D object). The markers may be geometrical markers. The marker may be a physical (e.g., comprising material) addition and/or omission to the 3D object. The markers may be metrological markers. The marker may be a material property of the 3D object (e.g., a mark within the material which the 3D object consists of, e.g., a microstructure). The marker may be a pore, dislocation, or crack. The marker may comprise a metallurgical or crystalline feature. FIG. 1 shows an example of a model of a 3D object 100 that comprises markers (e.g., 101) in the form of (e.g., substantially) circular holes.
[0133]The position, and/or geometry (e.g., shape and/or size) of the markers may be chosen such the markers may be monitored during and/or after a forming process (e.g., 3D printing) of a 3D object. The position, and/or geometry (e.g., shape and/or size) of the markers may be chosen such that two subsequent markers may not merge during and/or after the forming process (e.g., 3D printing) (e.g., based on an estimated deformation maximum). The position and/or geometry of the markers may be chosen such that two subsequent markers may not cause alteration (e.g., deformation) in the 3D object that will prevent the forming process (e.g., printing in the 3D printer). Prevent the forming process may be due to hardware constraints. The estimate may be a crude estimate. The position, and/or geometry (e.g., shape and/or size) of the markers may be chosen such that the markers will not (e.g., substantially) affect the overall behavior of the 3D object during and/or after the forming process (e.g., 3D printing).
[0134]The one or more markers may serve as a tracking device of the forming process (e.g., 3D printing process). FIG. 1 shows an example of a model of a 3D object that comprises markers (e.g., 101, 102, 103, 104 and 105); and a 3D object 110 that was formed (e.g., printed) 120 based on the model 100, which formed (e.g., printed) 3D object comprises respective markers (e.g., 111, 112, 113, 114 and 115), wherein respective is to the model 100. The tracking may be of (i) the entire 3D object after its formation, (ii) various stages of the 3D object during its formation (e.g., 3D printing) process and/or (iii) of various portions of the formed (e.g., printed) 3D object.
[0135]In the forming process (e.g., 3D printing), a requested 3D object can be formed (e.g., printed) according to (e.g., printing) instructions, which are based at least in part on a model of a desired 3D object. The model may comprise a computer model, geometric model, corrected geometric model, test model, marked model, or a marked geometric model. The geometric model may comprise a CAD model. The geometric model may be a virtual model, e.g., a computer-generated model (of the 3D object). The geometric model may be a virtual representation of the geometry of the 3D object, e.g., in the form of 3D imagery. In some cases, a geometric model corresponds to an image (e.g., scan) of an object (e.g., a test object). The model of the desired 3D object can be manipulated to incorporate the one or more model markers to form a model of the marked 3D object (also referred herein as a “test model”). The model of the marked 3D object (i.e., the “test model”) may be incorporated in (e.g., printing) instruction to generated a physically (e.g., structurally) marked 3D object (also referred herein as the “test 3D object”, “test object” or “test part”) that incorporates physical one or more markers (also referred to herein as a “physical markers”, “structural markers” or “test markers”, e.g., depending on the type of object). The structural marker may be a geometric marker. A model of the object can have one or more markers (also referred to herein as “model markers”, “image markers”, “virtual markers” or “test markers”, depending on the type of model) corresponding to the one or more physical markers.
[0136]The one or more model markers (also referred to herein as “test markers”) that are embedded in the model of the 3D object, may be embedded at one or more positions respectively. FIG. 1 shows an example of two markers 102 and 103 that are embedded in the model 100 of the 3D object, which markers are separated by a distance d1. Model 100 also comprises model markers (e.g., 101, 104 and 105). The one or more positions of the markers (e.g., 101, 102, 103, 104 and 105) may comprise random, or specific positions. The one or more positions can form an array. The array may be an organized array. The one or more positions may be predetermined positions (e.g., on the model of the 3D object). For example, the one or more positions may be on a portion of the requested 3D object that is susceptible to alteration (e.g., deformation). The alteration (e.g., deformation) may comprise warping, buckling, bending, balling, or twisting. The alteration (e.g., deformation) may comprise squeezing and/or stretching the material of the 3D object. The deformation may be due to material stress and/or strain. The deformation may occur during and/or after forming the 3D object, e.g., during and/or after the formation of a hardened material. The deformation may occur due to the forming (e.g., 3D printing) process and/or properties of the particular material(s) used in the forming (e.g., 3D printing).
[0137]In some embodiments, the 3D object(s) is/are formed using one or more 3D printing processes. In one embodiment, the process of 3D printing comprises additive manufacturing. Three-dimensional printing may comprise depositing a first (e.g., substantially planar (e.g., planar)) layer of pre-transformed material to form a material bed; directing an energy beam towards a first portion of the first layer of pre-transformed material to form a first transformed material according to a first slice in a model (e.g., a computer model (e.g., geometric model)) of a three-dimensional object. In some embodiments, the three-dimensional printing comprises using one or more laser engineered net shaping, direct metal deposition, and laser consolidation techniques. The transformed material may be a portion of the 3D object. The transformed material may be hardened into a hardened (e.g., substantially solid (e.g., solid)) material as part of the 3D object. Optionally, this process may be repeated layer by layer. For example, by adding a second (e.g., substantially planar (e.g., planar)) layer of pre-transformed material, directing the energy beam towards a second portion of the second layer of pre-transformed material to form a second transformed material according to a second slice in a (geometric) model of a 3D object. In some embodiments, the 3D object is formed using a material bed. The material bed may be at a (e.g., substantially) constant pressure during the forming process. For example, the material bed may be devoid of a pressure gradient during the forming process. The material bed (e.g., powder bed) may comprise flowable material (e.g., powder) during the forming process. In some example, the 3D object (or a portion thereof) may be formed in the material bed without being anchored (e.g., to the platform). For example, the 3D object may be formed without auxiliary supports. The 3D object may be formed without any externally applied pressure gradient(s). For example, the material bed can be under (e.g., substantially) constant pressure (e.g., having (e.g., substantially) no pressure gradients). For example, the material bed can remain in a flowable (e.g., not fixed) state during a transformation process. 3D printing processes; various materials; and 3D printing methods, systems, apparatuses, controller (e.g., including the processor) and software (e.g., including energy beams), are described in PCT Patent Applications serial numbers PCT/US2015/065297, PCT/US16/34857, and PCT/US17/18191; European patent application serial number EP17156707.6; U.S. patent application Ser. No. 15/435,065; and in U.S. provisional patent application Ser. No. 62/401,534, each of which is incorporated herein in its entirety.
[0138]FIG. 2 shows an example of a 3D printer 200 comprising a chamber 207 (also referred to herein as processing chamber) having an inner atmosphere 226 enclosed in an inner volume, which atmosphere comprises one or more gasses; an energy source 221 generating an energy beam 201; a scanner 220 that aids in translation of the energy beam (e.g., according to a pattern); an optical window 215; a material dispenser 216; a material leveling member 217; a material removal member 218; an optional cooling member (e.g., heat sink) 213; a material bed 204 comprising an exposed surface 219, a (e.g., forming) 3D object 206; a platform comprising a base 202 and a substrate 209, which platform is configured to support the 3D object, which platform is separated from the enclosure by a barrier (e.g., 203), which platform is disposed on an actuator (e.g., elevator) 205 that is vertically translatable 212, which chamber has a bottom portion 211, which platform has a bottom portion 210, which scanner and energy source are disposed outside of the enclosure 207. The processing chamber can enclose at least a portion of the 3D object during its formation. The energy beam can translate (e.g., travel) through a region (sometime referred to as a processing cone) within the processing chamber during the 3D printing. Sometimes it is desirable for the processing cone to be (e.g., substantially) free of particles (e.g., debris) during the 3D printing. One or more controller can be configured to vertically translate the platform. In some embodiments, at least one of the material removal member, the material leveling member, the cooling member, the base, and the optical window are optional components. At times, the energy source and/or the scanner 220 are disposed within the enclosure. The enclosure may be open or closed to the ambient environment. The enclosure may comprise one or more openings (e.g., doors and/or windows). The enclosure may comprise a load lock. The actuator and/or the building platform may be an integral part of the enclosure, or separate part of the enclosure that may be reversibly connected to the enclosure.
[0139]At times, a formed (e.g., printed) portion of the 3D object may (e.g., substantially) deviate from the model of the 3D object during and/or after the forming (e.g., 3D printing), e.g., during and/or after the formation of the hardened material. Substantially deviate may be in relation to the intended purpose of the 3D object. For example, manufacturing requirements may dictate that particular dimensions of the 3D object are within a specified threshold (e.g., tolerance). Such deviation may comprise deformation. FIG. 1 shows an example of a structural deviation in a general sense. FIG. 1 shows an example of a model of a 3D object comprising a bent structure 100, and its respective formed (e.g., printed) 3D object comprising a planar structure 110 that deviates from the bent structure 100. Inclusion of one or more markers in the model of the 3D object, and subsequently in the generated 3D object, may provide information on the extent, location, and/or type of alteration (e.g., deformation) that results from forming the 3D object. At times, the inclusion of the one or more markers may shed light on the process that leads to the alteration (e.g., deformation). The markers may be structural (e.g., geometrical) markers. The markers may be physical markers (e.g., structural markers). The markers may be metrological markers. The markers may provide metrological information (measurable information) regarding the generation process of the 3D object. The markers may be material markers.
[0140]In some embodiments, the positions (also referred to herein as “locations”, “physical positions” or “physical locations”) and/or form of the one or more markers of the test 3D object (also herein “physical positions”) and the position of the one or more markers of the test model (also herein “locations”, “model positions” or “model locations”) may be compared. In some embodiments, (i) the positions and/or form (e.g., structure) of the one or more markers (that are physically marked (e.g., structurally marked)) of the 3D object, and (ii) the position of the one or more markers of the model of the marked 3D object, may be compared. At times the physical marker positions may deviate from the model marker positions. At times, the physical marker positions may (e.g., substantially) coincide with the model marker positions. At times the physical marker shape may deviate from the model marker shape. At times, the physical marker shape may (e.g., substantially) coincide with the model marker shape. The physical markers may be referred herein as “test markers.” In some embodiments, substantially coincide is in relation to (e.g., within) a predetermined threshold or limit. In some embodiments, comparing locations of markers (e.g., model markers and test markers) and/or determining whether they substantially coincide, involves performing one or more data analysis techniques. In some embodiments, data analysis techniques described herein involves one or more regression analys(es) and/or calculation(s). The regression analysis and/or calculation may comprise linear regression, least squares fit, Gaussian process regression, kernel regression, nonparametric multiplicative regression (NPMR), regression trees, local regression, semiparametric regression, isotonic regression, multivariate adaptive regression splines (MARS), logistic regression, robust regression, polynomial regression, stepwise regression, ridge regression, lasso regression, elasticnet regression, principal component analysis (PCA), singular value decomposition (SVD)), probability measure techniques (e.g., fuzzy measure theory, Borel measure, Harr measure, risk-neutral measure, Lebesgue measure), predictive modeling techniques (e.g., group method of data handling (GMDH), Naive Bayes classifiers, k-nearest neighbors algorithm (k-NN), support vector machines (SVMs), neural networks, support vector machines, classification and regression trees (CART), random forest, gradient boosting, generalized linear model (GLM)), or any other suitable probability and/or statistical analys(es). In some cases, the comparison involves comparing relative locations of the markers (e.g., model markers) with respect to each other and/or to markers on another object (e.g., a test object). In some cases, some of the markers are removed (redacted). The markers may include edges, kinks, or rims of an object. The markers may comprise borders of geometric model components that are manifested on the physical 3D object. For example, the markers may comprise tessellation borders of the geometric model that are manifested on the physical 3D object. In some cases, certain portions of the object will experience more alteration (e.g., deformation) as a result of the forming process, as compared to other portions of the object. The portions that experience more alteration may result in more deviation between physical positions and model positions of the markers. The portions of the (physical) 3D object and/or (virtual) model of the 3D object at which deviation is detected, may be positions susceptible to alteration (e.g., deformation). The portions of the 3D object and/or model at which deviation is not detected, may be positions (e.g., substantially) free of alteration (e.g., deformation). FIG. 1 shows an example where the markers 114 and 115 in the formed (e.g., printed) 3D object 110 moved as compared to their respective positions of markers 102 and 103 in the model 100 of that 3D object, as can be detected inter alia from the difference in their respective distances d2 as compared to d1. FIG. 1 shows an example where the markers 111 and 113 in the formed (e.g., printed) 3D object changed in shape and density as compared to their respective markers 104 and 105 in the model of that 3D object: round marker 104 of the model, became elongated marker 111, markers in the area of 105 of the test model became denser in the test 3D object in the respective area of 113. These types of shape changes of the markers may or may not be of significance. For example, in some embodiments, such shape changes are treated as permissible variation (e.g., within a tolerance). In some embodiments, the shape changes are measurable and included within the data analys(es). In some embodiments, the shape of the markers does not (e.g., substantially) change as a result of the forming process. For example, FIG. 1 shows model marker 101 having a symmetrically round cross-section shape, resulting in physical marker 112 having a corresponding symmetrically round cross-section shape.
[0141]The comparison between the test model (e.g., 100) and the test object (e.g., test 3D object, 110) may allow for empirical estimation and/or (simulated) prediction of deformation. An estimated alteration (e.g., deformation) based on empirical evidence (referred to herein as “empirical process”, “empirical method” or “empirical estimation”) can involve deriving results from one or more formed (e.g., printed) objects. For example, dimensions of one or more formed objects can be measured (using any suitable technique) and compared to corresponding dimensions of a geometric model (from which the forming (e.g., printing) instructions are derived). Differences between the dimensions can then be used to predict what portions of an object are most likely to deform (and/or an overall deformation of the object) due to the forming process. In some cases, the differences can include differences in an expected density (e.g., porosity), material consistency, metallurgical shape (e.g., and their distribution), and/or other aspects of an object. As described above, in some embodiments, the geometric model includes one or more model markers (e.g., protrusions, recesses and/or deletions) that result in corresponding physical markers of the formed object. Spacing (distances) between the physical markers can be compared to respective spacing (distances) between corresponding model markers, to determine regions of the object that experience more deformation than other regions. The comparison between the test model (geometric model) and a test object (e.g., test 3D object) may allow the design of forming (e.g., printing) instructions (e.g., 3D printing instructions) that can result in reduction of deformation. The comparison between the test model and the test object (e.g., test 3D object) may allow the design of forming (e.g., printing) instructions (e.g., 3D printing instructions) that result high fidelity forming (e.g., printing) of the 3D object. The comparison between the (virtual) test model and the (physical) test object may aid an understanding and/or differentiation between various mechanisms that cause alteration (e.g., deformation and/or addition) to at least a portion of the 3D object. For example, differentiation between expansion and extension mechanisms. For example, various mechanisms leading to dimensional inaccuracy. The comparison between the test model (e.g., 100) and the test object (e.g., test 3D object, 110) may comprise comparing their respective markers (e.g., in terms of relative distances, FLS, volume, and/or shape). The result may aid in experimental calculation of (internal) stresses and/or strains of at least a portion of the 3D object. The experimental calculation(s) may allow for an understanding of the material behavior during the forming process (e.g., the material from which the 3D object is built, or the desired material for the 3D object). In some embodiments, the comparison and/or strategic placement of the one or more markers may facilitate formation of functionally graded materials (e.g., comprising various microstructures at different portions of the 3D object). FIG. 10 shows an example of a requested 3D object 1020, deformed 3D object 1000 respective to the requested 3D object 1020, and a 3D object 1012 that comprises additions 1010 (e.g., in the form of stalactites, which can extend beyond height H of the requested object 1020) with respect to the requested 3D object 1020.
[0142]High fidelity forming (e.g., printing) may refer to the degree of deviation of the formed (e.g., printed) 3D object from a model of that 3D object. The 3D object (e.g., solidified material) that is generated (e.g., for a customer) can have an average deviation value from its intended dimensions (e.g., as specified by its respective 3D model) of at most about 0.5 microns (μm), 1 μm, 3 μm, 10 μm, 30 μm, 100 μm, 300 μm afore-mentioned values (e.g., from about 0.5 μm to about 300 μm, from about 10 μm to about 50 μm, from about 15 μm to about 85 μm, from about 5 μm to about 45 μm, or from about 15 μm to about 35 μm). The 3D object can have a deviation from the intended dimensions (e.g., model dimensions) in at least one specific direction. The deviation in at least one specific direction can follow the formula Dv+L/Kdv, wherein Dv is a deviation value, L is the length of the 3D object in a specific direction, and Kdv is a constant. Dv can have a value of at most about 300 μm, 200 μm, 100 μm, 50 μm, 40 μm, 30 μm, 20 μm, 10 μm, 5 μm, 1 μm, or 0.5 μm. Dv can have any value between the afore-mentioned values (e.g., from about 0.5 μm to about 300 μm, from about 10 μm to about 50 μm, from about 15 μm to about 85 μm, from about 5 μm to about 45 μm, or from about 15 μm to about 35 μm). Kdv can have a value of at most about 3000, 2500, 2000, 1500, 1000, or 500. Kdv can have a value of at least about 500, 1000, 1500, 2000, 2500, or 3000. Kdv can have any value between the afore-mentioned values. Kdv can have a value that is from about 3000 to about 500, from about 1000 to about 2500, from about 500 to about 2000, from about 1000 to about 3000, or from about 1000 to about 2500. For example, the generated 3D object may deviate from the requested 3D object by at most about the sum of 100 micrometers and 1/1000 times the fundamental length scale of the requested 3D object. The generated 3D object may deviate from the requested 3D object by at most about the sum of 25 micrometers and 1/2500 times the fundamental length scale of the requested 3D object.
[0143]The result may aid in generating and/or alter 3D forming (e.g., printing) instructions. The forming (e.g., printing) instructions may comprise the geometry of a desired 3D object and optionally an alteration (e.g., a change) thereof. The alteration may be a geometric alteration. The alteration may comprise a corrective alteration (e.g., corrective deviation, corrective deformation, or object pre-correction). The forming (e.g., printing) instructions may comprise altering one or more process parameters of the 3D printing. For example, the forming (e.g., printing) instructions may comprise controlling one or more energy beam characteristics (e.g., power density, path, and/or hatching), which can individually or collectively be altered. In some embodiments, the energy beam path used during one or more forming operations for forming an object is adjusted. In some embodiments, the speed of the energy beam is varied depending on whether is transforming a region (e.g., critical regions versus non-critical regions) of the 3D object. A critical region can be one that is prone to deformation (e.g., during and/or after the forming process). For example, the energy beam may be at a first speed when transforming a first region of the object, and at a second speed (e.g., slower or faster than the first speed) when transforming a second region of the object. In some cases, this varied speed can be used to adjust (e.g., optimize or increase) throughput while maintaining quality of certain regions of the object. FIG. 3 shows an example of an energy beam path 301. The path may comprise an oscillating sub-path shown as a magnified path example 302. FIG. 4 shows various examples of energy beam paths and/or hatchings; for example, paths 410, 411, and 416 comprise continuous paths; paths 412, 413, 414, and 415 comprise discontinuous paths comprising a plurality of sub paths (e.g., hatchings); and the arrows designate the direction at which the energy beam travels along the paths or sub-paths. The energy beam can be a scanning energy beam, tiling energy beam, or a combination of both. Examples of scanning and tiling energy beams are described in U.S. patent application Ser. No. 15/435,065, filed on Feb. 16, 2017, which is incorporated by reference herein in its entirety. In some embodiments, the one or more processing parameters may be altered based on empirical data collected during and/or after a forming process. For example, comparison of a geometric model and a corresponding object (e.g., test object) can be used to determine regions of the object that experienced more deformations than other regions. This information can be used to modify the forming instructions (e.g., in these regions) to at least partially compensate for such deformations. For instance, a power density of the energy beam (e.g., laser beam) can be modified (e.g., decreased or increased) as the energy beam transforms a pre-transformed material of a region to a transformed material. In some cases, the energy beam is modified from a scanning energy beam to a tiling energy beam (or vice versa). In some cases, the footprint of the energy beam on the exposed surface of the material bed is modified. In some cases, the path of the energy beam is modified. The comparison between the geometric model (e.g., (virtual) model markers) and the object (e.g., physical markers) can be performed in real time (e.g., during the forming of the object), such that the one or more process modifications can occur in situ. In this way, the one or more markers may serve as a tracking device of a forming (e.g., printing) process. Real time may be during forming of the 3D object, a plurality of layers of the 3D object, a layer of the 3D object, a hatch line as part of a layer of a 3D object, a plurality of hatch lines, a melt pool, or a plurality of melt pools. A plurality may be any integer number from 2 to 10. A plurality may be any integer number of at least 2, or of at least 10.
[0144]The comparison between the test model and the test object (e.g., test 3D object) may give a result. The comparison of a metrological characteristics (e.g., distance and/or shape) between at least two markers in test model and the respective at least two markers of the test object (e.g., test 3D object) may give a result. The comparison of a metrological characteristics of at least one marker in test model and the respective at least one marker of the test object (e.g., test 3D object) may give a result. The metrological characteristics of a marker may comprise its FSL, shape, or volume.
[0145]In some embodiments, the test 3D object is different from the 3D object at least due to the presence of one or more markers in the test 3D object. The one or more markers may be chosen such that the difference between the test 3D object and the requested (e.g., desired) 3D object is insubstantial. Insubstantial change may be relative to a mechanical variation and/or deformation (e.g., of the portion where the one or more markers reside). For example, when the metrological characteristics measured is a distance between the (e.g., center) of two markers, and the comparison of this respective distance between the test model and the test 3D object, a small change is one that is at most B according to the following metric: (a measured distance between a first marker and a second marker in the test 3D object), divided by (a measured distance between the respective first marker and a second marker in the test model)=1+B. B can be at most about 0.001, 0.005, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, or 0.2. B can be between any o