METHODS, SYSTEMS, AND COMPUTER PROGRAM PRODUCTS FOR DETERMINING FABRICATION PARAMETERS USED IN THREE-DIMENSIONAL (3D) CONTINUOUS LIQUID INTERFACE PRINTING (CLIP) SYSTEMS, AND RELATED PRINTERS

A method of determining Parameters for application to Continuous Liquid Interface Printing (CLIP) can be provided by receiving an objective input for fabrication using a CLIP printer and determining best Parameters to be applied to the CLIP Printer during Fabrication using a model that defines a relationship between the objective input and Parameters to be applied during fabrication.

FIELD

The present invention relates, generally, to the fabrication of three-dimensional objects and, more particularly, to additive production of three-dimensional objects.

BACKGROUND

In some conventional additive fabrication techniques, construction of a three-dimensional object may be performed in a step-wise or layer-by-layer manner. For example, layers may be formed through solidification of a photo curable resin responsive to visible or UV light irradiation. One such known technique can provide new layers formed at the top surface of an object being fabricated. Another technique can provide new layers at the bottom surface of the object being fabricated.

Some examples of these approaches are discussed in U.S. Pat. Nos. 5,236,637, 7,438,846, 7,892,474, US Patent Publication No. 2013/0292862, and US Patent Publication No. 2013/0295212.

Another approach includes that used by the B9Creator™ 3D printer marketed by B9Creations of Deadwood, S. Dak., USA.

SUMMARY

A method of determining Parameters for application to a Continuous Liquid Interface printer (CLIP), can be provided by receiving an objective input for fabrication using a CLIP printer and determining best Parameters to be applied to the CLIP printer during fabrication using a model that defines a relationship between the objective input and Parameters to be applied during fabrication.

DETAILED DESCRIPTION OF EMBODIMENTS ACCORDING TO THE INVENTION

As described herein, while a variety of additive manufacturing methods and apparatus may be used, in some embodiments, the 3D objects can be produced using a liquid interface, which may be referred to as remote “Continuous Liquid Interface Printing” or “Continuous Liquid Interface Production” (CLIP), these terms being used interchangeably. It will be understood that in some embodiments according to the invention, the term “continuous” (or “continuously”) can refer to the formation of at least some contiguous portions of the 3D object in situ. For example, in some embodiments according to the invention, different portions of the 3D object, which are contiguous with one another in the final 3D object, can both be formed sequentially within a gradient of polymerization. Furthermore, a first portion of the 3D object can remain in the gradient of polymerization while a second portion, that is contiguous with the first portion, is formed in the gradient of polymerization. Accordingly, the 3D object can be fabricated, grown or produced continuously from the gradient of polymerization (rather than fabricated in discrete layers).

CLIP may be carried out as a bottom-up three dimensional additive manufacturing technique. In general, bottom-up additive manufacturing may be carried out by: (a) providing a carrier and an optically transparent member having a build surface, said carrier and said build surface defining a build region therebetween; (b) filling said build region with a polymerizable liquid, said polymerizable liquid comprising a mixture of (i) a light (typically ultraviolet light) polymerizable liquid first component, and (ii) a second solidifiable component of the dual cure system; (c) irradiating said build region with light through said optically transparent member to form a solid polymer scaffold from said first component and also advancing said carrier away from said build surface to form a three-dimensional intermediate having the same shape as, or a shape to be imparted to, said three-dimensional object and containing said second solidifiable component (e.g., a second reactive component) carried in said scaffold in unsolidified and/or uncured form; and (d) concurrently with or subsequent to said irradiating step, solidifying and/or curing (e.g., further reacting, further polymerizing, further chain extending), said second solidifiable component (e.g., by heating and/or microwave irradiating) in said three-dimensional intermediate to form said three-dimensional object.

As noted above, the products are preferably formed by continuous liquid interface production (CLIP). CLIP is known and described in, for example, PCT Applications Nos. PCT/US2014/015486 (also published as US 2015/0102532); PCT/US2014/015506 (also published as US 2015/0097315), PCT/US2014/015497 (also published as US 2015/0097316), and in J. Tumbleston, D. Shirvanyants, N. Ermoshkin et al., Continuous liquid interface production of 3D Objects, Science 347, 1349-1352 (published online 16 Mar. 2015), all of which are hereby incorporated herein by reference. In some embodiments, CLIP employs features of a bottom-up three dimensional fabrication as described above, but the the irradiating and/or said advancing steps are carried out while also concurrently: (i) continuously maintaining a dead zone of polymerizable liquid in contact with said build surface, and (ii) continuously maintaining a gradient of polymerization zone (such as an active surface) between said dead zone and said solid polymer and in contact with each thereof, said gradient of polymerization zone comprising said first component in partially cured form. In some embodiments of CLIP, the optically transparent member comprises a semipermeable member (e.g., a fluoropolymer), and said continuously maintaining a dead zone is carried out by feeding an inhibitor of polymerization through said optically transparent member, thereby creating a gradient of inhibitor in said dead zone and optionally in at least a portion of said gradient of polymerization zone.

In some embodiments, CLIP may be carried out by optically establishing the dead zone and gradient of polymerization/active surface, such as by techniques explained in US Patent Application Publication No. US 2004/0181313 to Shih et al., in U.S. Pat. No. 8,697,346 to McLeod et al., S. Hell et al., Nanoscale Resolution with Focused Light: STED and Other RESOLFT Microscopy Concepts, in Handbook of Biological Confocal Microscopy (J. Pawley ed., 3d Ed. 2006); T. Andrew et al., Science, 324, 917-921 (2009); and T. Scott et al., Science 324, 913-917 (2009), all of which are hereby incorporated herein by reference. In such case, the window or build plate may be either semipermeable, or may be impermeable to an inhibitor of polymerization (e.g., a single glass sheet). In some embodiments, CLIP may be carried out by generating the inhibitor of polymerization electrochemically, such as by an optically transparent electrode or electrode array associated with the window or build plate, by which oxygen is electrochemically generated from water included in the polymerizable liquid. Again, in such case, the window or build plate may be either semipermeable (e.g., a fluoropolymer) or may be impermeable to an inhibitor of polymerization (e.g., a single glass sheet).

While the dead zone and the gradient of polymerization zone do not have a strict boundary therebetween (in those locations where the two meet), the thickness of the gradient of polymerization zone is in some embodiments at least as great as the thickness of the dead zone. Thus, in some embodiments, the dead zone has a thickness of from 0.01, 0.1, 1, 2, or 10 microns up to 100, 200 or 400 microns, or more, and/or the gradient of polymerization zone and the dead zone together have a thickness of from 1 or 2 microns up to 400, 600, or 1000 microns, or more. Thus the gradient of polymerization zone may be thick or thin depending on the particular process conditions at that time. Where the gradient of polymerization zone is thin, it may also be described as an active surface on the bottom of the growing three-dimensional object, with which monomers can react and continue to form growing polymer chains therewith. In some embodiments, the gradient of polymerization zone, or active surface, is maintained (while polymerizing steps continue) for a time of at least 5, 10, 15, 20 or 30 seconds, up to 5, 10, 15 or 20 minutes or more, or until completion of the three-dimensional product.

The method may further comprise the step of disrupting the gradient of polymerization zone for a time sufficient to form a cleavage line in the three-dimensional object (e.g., at a predetermined desired location for intentional cleavage, or at a location in the object where prevention of cleavage or reduction of cleavage is non-critical), and then reinstating the gradient of polymerization zone (e.g. by pausing, and resuming, the advancing step, increasing, then decreasing, the intensity of irradiation, and combinations thereof).

CLIP may be carried out in different operating modes operating modes (that is, different manners of advancing the carrier and build surface away from one another), including continuous, intermittent, reciprocal, and combinations thereof.

Thus in some embodiments, the advancing step is carried out continuously, at a uniform or variable rate, with either constant or intermittent illumination or exposure of the build area to the light source.

In other embodiments, the advancing step is carried out sequentially in uniform increments (e.g., of from 0.1 or 1 microns, up to 10 or 100 microns, or more) for each step or increment. In some embodiments, the advancing step is carried out sequentially in variable increments (e.g., each increment ranging from 0.1 or 1 microns, up to 10 or 100 microns, or more) for each step or increment. The size of the increment, along with the rate of advancing, will depend in part upon factors such as temperature, pressure, structure of the article being produced (e.g., size, density, complexity, configuration, etc.).

In some embodiments, the rate of advance (whether carried out sequentially or continuously) is from about 0.1 1, or 10 microns per second, up to about to 100, 1,000, or 10,000 microns per second, again depending again depending on factors such as temperature, pressure, structure of the article being produced, intensity of radiation, etc.

In still other embodiments, the carrier is vertically reciprocated with respect to the build surface to enhance or speed the refilling of the build region with the polymerizable liquid. In some embodiments, the vertically reciprocating step, which comprises an upstroke and a downstroke, is carried out with the distance of travel of the upstroke being greater than the distance of travel of the downstroke, to thereby concurrently carry out the advancing step (that is, driving the carrier away from the build plate in the Z dimension) in part or in whole.

While CLIP is the preferred additive manufacturing technique for carrying out the present invention, it will be appreciated that other bottom-up or top-down additive manufacturing techniques, including ink jet printer techniques, may also be used. Such methods are known and described in, for example, U.S. Pat. No. 5,236,637 to Hull, U.S. Pat. No. 7,438,846 to John, U.S. Pat. No. 8,110,135 to El-Siblani, and U.S. Patent Application Publication Nos. 2013/0292862 to Joyce and 2013/0295212 to Chen et al. The disclosures of these patents and applications are incorporated by reference herein in their entireties.

Additional examples of apparatus, polymerizable liquids (or “resins”), and methods that may be used in carrying out the present invention include, but are not limited to, those set forth in J. DeSimone et al., Three-Dimensional Printing Using Tiled Light Engines, PCT Publication No. WO/2015/195909 (published 23 Dec. 2015); J. DeSimone et al., Three-Dimensional Printing Method Using Increased Light Intensity and Apparatus Therefore, PCT Publication No. WO/2015/195920 (published 23 Dec. 2015), A. Ermoshkin et al., Three-Dimensional Printing with Reciprocal Feeding of Polymerizable Liquid, PCT Publication No. WO/2015/195924 (published 23 Dec. 2015); J. Rolland et al., Method of Producing Polyurethane Three-Dimensional Objects from Materials having Multiple Mechanisms of Hardening, PCT Publication No. WO 2015/200179 (published 30 Dec. 2015); J. Rolland et al., Methods of Producing Three-Dimensional Objects from Materials Having Multiple Mechanisms of Hardening, PCT Publication No. WO 2015/200173 (published 30 Dec. 2015); J. Rolland et al., Three-Dimensional Objects Produced from Materials Having Multiple Mechanisms of Hardening, PCT Publication No. WO/2015/200189 (published 30 Dec. 2015); J. Rolland et al., Polyurethane Resins Having Multiple Mechanisms of Hardening for Use in Producing Three-Dimensional Objects published 30 Dec. 2015); and J. DeSimone et al., Methods and Apparatus for Continuous Liquid Interface Production with Rotation, PCT Publication No. WO/2016/007495, the disclosures of which are incorporated by reference herein in their entirety.

In an alternate embodiment of the invention, the methods may be carried out with a method and apparatus as described in Hull, U.S. Pat. No. 5,236,637, atFIG. 4, where the polymerizable liquid is floated on top of an immiscible liquid layer (said to be “non-wetting” therein). Here, the immiscible liquid layer serves as the build surface. If so implemented, the immiscible liquid (which may be aqueous or non-aqueous) preferably: (i) has a density greater than the polymerizable liquid, (ii) is immiscible with the polymerizable liquid, and (iii) is wettable with the polymerizable liquid. Ingredients such as surfactants, wetting agents, viscosity-enhancing agents, pigments, and particles may optionally be included in either or both of the polymerizable liquid or immiscible liquid.

While the present invention is preferably carried out by continuous liquid interphase polymerization, as described in detail above, in some embodiments alternate methods and apparatus for bottom-up three-dimension fabrication may be used, including layer-by-layer fabrication. Examples of such methods and apparatus include, but are not limited to, those described U.S. Pat. Nos. 7,438,846 to John and U.S. Pat. No. 8,110,135 to El-Siblani, and in U.S. Patent Application Publication Nos. 2013/0292862 to Joyce and 2013/0295212 to Chen et al. The disclosures of these patents and applications are incorporated by reference herein in their entirety.

The fabrication of 3D objects is also described in U.S. Pat. Nos. 9,216,546; 9,211,678; and 9,205,601, the contents of all of which are hereby incorporated herein by reference.

FIG. 1is a schematic diagram of a 3D object100for fabrication using a Continuous Liquid Interface Production (CLIP) printer in some embodiments according to the invention. According toFIG. 1, the 3D object100can be represented as a collection of contiguous Portions1-N of the 3D object100. The contiguous Portions1-N can correspond (1:1) to respective Slices S1-SN of a data set representing the 3D object100. The Portions1-N can, however, correspond to an arbitrary number of Slices of the data set and to an arbitrary thickness of the 3D object100.

As further shown inFIG. 1, each of the Portions1-N can have an associated set of Parameters applied to the CLIP printer for fabrication of the 3D object100. In other words, each of the Portions1-N can have a respective set of Parameters such that the Parameters applied to the CLIP printer can vary depending on which Portion of the 3D object100being currently fabricating. For example, when the first Portion (1) is being fabricated, the set of Parameters (1) is applied to the CLIP printer. When, however, the next contiguous Portion (2) is to be fabricated, the set of Parameters (2) can be applied to the CLIP printer for use in fabrication. It will be understood that the each sets of the Parameters1-N can be different or can be repeated. For example, in some cases Parameters (1-10) may be the same as one another whereas in other cases each of the Parameters (1-10) may be different from one another. Also, a complete schedule of Parameters1-N can be maintained for a particular 3D object, which are applied in sequence once fabrication begins.

FIG. 2Ais a flowchart illustrating operations of a system for determining the Parameters used to fabricate the 3D object100ofFIG. 1using a CLIP printer in some embodiments according to the invention. According toFIG. 2A, the system can receive an objective for the 3D fabrication as an input (220). The objective input can be, for example, the speed at which the fabrication is to be carried out, the resolution at which the fabrication is to be carried out, etc. Once the objective is provided (220), the system can determine the best Parameters to be applied to the CLIP Printer during Fabrication using a model that defines a relationship between the objective input and the Parameters to be applied (225).

FIG. 2Bis a flowchart illustrating operations of a system for determining the Parameters used to fabricate the 3D object100ofFIG. 1using a CLIP printer in some embodiments according to the invention. According toFIG. 2B, the system can receive an objective for the 3D fabrication as an input (205). The objective input can be, for example, the speed at which the fabrication is to be carried out, the resolution at which the fabrication is to be carried out, etc. Once the objective is provided (205), the Parameters to possibly be applied to the CLIP printer for fabrication of the 3D object can be determined (210). Once the possible Parameters are determined (210), the best set of possible Parameters can be selected for application to the CLIP printer for fabrication of the 3D object (215).

FIG. 4is a flowchart illustrating operations of the system inFIG. 2Bto determine Parameters used to fabricate the 3D object ofFIG. 1using simulation in some embodiments according to the invention. According toFIG. 3, to determine the Parameters that may possibly be applied to the CLIP printer for the fabrication of the 3D object (210), a variable N identifying the particular Portion of the 3D object can be initialized to 1 (305). Also, a variable M identifying a particular set of Parameters for a particular portion of the 3D object is initialized to 1 (310).

The Parameters (M) are set for fabrication of a portion (N) of the 3D object (315). It will be understood that the Parameters (M) for fabrication associated with the portion (N) can be Parameters associated with processes in the CLIP printer that can be monitored and/or controlled during fabrication. For example, the Parameters can include the energy/frequency of the irradiation used to image the Portion, the temperature of the polymerizable liquid used to fabricate the 3D object100, etc.

Accordingly, a range of values for each of the Parameters (M) can be used to simulate the fabrication. For example, when the Parameter is temperature, a temperature value (over a certain range of temperature values) can be provided during each simulation (320) for the respective Portion (N). When, however, the Parameter is changed to the energy/frequency of the irradiation used, a value of the energy/frequency (over a certain range) is provided during each simulation (320) for the respective Portion (N).

The fabrication of portion (N) can be simulated using the set Parameters (M) (320). It will be understood that the simulation of the fabrication of Portions of the 3D object using Parameters (M) can be provided using the relationships described in Tumbleston “Continuous Liquid Interface Printing of 3D Objects” Science Magazine Mar. 2015, the entirety of which is incorporated herein by reference.

If another set of Parameters (M) are to be used to simulate the fabrication (325), the variable M is incremented by 1 (330) and operations continue at step (315). The iteration of (315-325) continues until no more Parameters for the portion (N) are to be simulated, whereupon, the Parameters set which best meets the objective provided for the portion (N) is determined (335) and is saved as the Parameters (N) so that it is associated with Portion (N) (340).

If more Portions of the 3D object are to be simulated (345), the variable (N) is incremented by 1 (350) and iteration of (310-345) continues until all Portions (N) have been simulated with all Parameters, operations can continue by assembling a schedule that associates each Portion (N) with the Parameters (N) which best meets the objective for that particular Portion. Accordingly, when fabricating, the Parameters (N) selected for each of the Portions (N) can be provided for use in fabricating the 3D object100.

As noted above, each of the Portions1-N may correspond to multiple Slices of the data set, and the set of Parameters may include, for example, index numbers identifying respective operating modes, parameters of operating modes, a slice thickness, a set of slice thicknesses, and the number of times slice thickness is changed.

FIG. 3shows an example of a generic computing device500, which may be used with the embodiments described herein. Computing device500is intended to represent various forms of digital computers, such as laptops, desktops, workstations, personal digital assistants, servers, blade servers, mainframes, controllers, and other appropriate computers. The components shown herein, their connections and relationships, and their functions, are meant to be exemplary only, and are not meant to limit implementations of the inventions described and/or claimed.

Computing device500includes a processor502, memory504, a storage device506, a high-speed interface508connected to memory504, and a high speed controller510. Each of the components is interconnected using various buses, and may be mounted on a common motherboard or in other manners as appropriate. The processor502can process instructions for execution within the computing device500, including instructions stored in the memory504or on the storage device506to display graphical information for a GUI on an external input/output device. In other implementations, multiple processors and/or multiple buses may be used, as appropriate, along with multiple memories and types of memory. Also, multiple computing devices500may be connected, with each device providing portions of the necessary operations (e.g., as a server bank, a group of blade servers, or a multi-processor system).

The computing device500may be implemented in a number of different forms. For example, it may be implemented as a standard server, or multiple times in a group of such servers. It may also be implemented as part of a rack server system. In addition, it may be implemented in a personal computer such as a laptop computer. Alternatively, components of computing device500may be combined with other components.

It will be appreciated that the above embodiments that have been described in particular detail are merely example or possible embodiments, and that there are many other combinations, additions, or alternatives that may be included.

Unless specifically stated otherwise as apparent from the above discussion, it is appreciated that throughout the description, discussions utilizing terms such as “processing” or “computing” or “calculating” or “determining” or “displaying” or “providing” or the like, refer to the action and processes of a computer system, or similar electronic computing device, that manipulates and transforms data represented as physical (electronic) quantities within the computer system memories or registers or other such information storage, transmission or display devices. In the figures, the thickness of certain lines, layers, components, elements or features may be exaggerated for clarity. Where used, broken lines illustrate optional features or operations unless specified otherwise.

As used herein, the term “and/or” includes any and all possible combinations or one or more of the associated listed items, as well as the lack of combinations when interpreted in the alternative (“or”).

It will be understood that when an element is referred to as being “on,” “attached” to, “connected” to, “coupled” with, “contacting,” etc., another element, it can be directly on, attached to, connected to, coupled with and/or contacting the other element or intervening elements can also be present. In contrast, when an element is referred to as being, for example, “directly on,” “directly attached” to, “directly connected” to, “directly coupled” with or “directly contacting” another element, there are no intervening elements present. It will also be appreciated by those of skill in the art that references to a structure or feature that is disposed “adjacent” another feature can have portions that overlap or underlie the adjacent feature.

Embodiments of the inventive subject matter are described herein with reference to plan and perspective illustrations that are schematic illustrations of idealized embodiments of the inventive subject matter. As such, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, the inventive subject matter should not be construed as limited to the particular shapes of objects illustrated herein, but should include deviations in shapes that result, for example, from manufacturing. Thus, the objects illustrated in the Figures are schematic in nature and their shapes are not intended to illustrate the actual shape of a region of a device and are not intended to limit the scope of the inventive subject matter.