WO2013113372A1

WO2013113372A1 - Techniques for three-dimensional printing

Info

Publication number: WO2013113372A1
Application number: PCT/EP2012/051535
Authority: WO
Inventors: Ramon VEGA AINSA; Luis BALDEZ; Ivan Jordi ESCODA MARTIN; Alejandro Manuel DE PENA HEMPEL
Original assignee: Hewlett-Packard Development Company, L.P.
Priority date: 2012-01-31
Filing date: 2012-01-31
Publication date: 2013-08-08

Abstract

Techniques for three-dimensional printing are described herein. In an example, a system is described for enabling a user to select a print setting specifically for a portion of an object to be printed by a 3D printing system.

Description

TECHNIQUES FOR THREE-DIMENSIONAL PRINTING

BACKGROUND

[0001] Three dimensional (3D) printing (also referred to as additive manufacturing, rapid prototyping or solid freeform fabrication) is emerging as a convenient technology for

manufacturing a vast variety of objects. The basic principle of 3D printing resides on building a product layer by layer from a particular material such as powered metal, droplets of plastic or any other appropriate material. A number of different technologies are available to perform 3D printing such as, for example, inkjet printing, digital light processing, fused deposition modeling, stereolithography, or laser sintering. The different technologies basically differ in the manner in which layers are built to create the object.

[0002] An advantage of 3D printing is the range of products that can be manufactured including a vast variety of industrial pieces, prosthetic implants, architectural reproductions, or even fashion articles such as shoes or dresses. Since 3D printing is able to reproduce shapes that mass production would find it impossible to reproduce, 3D printing is not merely an alternative method for manufacturing items that can be made by other means, but it also extends the range of products that can be made.

[0003] 3D printing generally involves generating a 3D geometric representation of one or more objects to be printed (i.e., manufactured by a 3D printer). Such a 3D geometric

representation may be referred to as 3D model. A 3D model may be stored in a 3D data file using a specific file format suitable for 3D printing. The 3D data file may be processed to generate instructions that are processed by a 3D printing system for reproducing the object. There are a variety of solutions for processing information in a 3D data file as well as to enable a user to define how an object should be manufactured using a 3D printing system.

BRIEF DESCRIPTION OF THE DRAWINGS

[0004] In order that the present disclosure may be well understood, various examples will now be described with reference to the following drawings.

[0005] FIG. 1 depicts an environment in which various examples may be implemented.

[0006] FIG. 2 depicts a system according to an example.

[0007] FIG. 3 is a block diagram depicting a computer readable medium according to an example.

[0008] FIG. 4 is a block diagram depicting an implementation of the system of Fig. 2.

[0009] FIGS. 5A-6 are flow diagrams that implement examples of methods for 3D printing of an object.

[0010] FIGS. 7A and 7B depict an example of a graphical user interface operated by the system in FIG. 2.

[0011] FIG. 8 depicts a diagram illustrating 3D printing of an object.

[0012] FIG. 9 schematically depicts a cross section of successive layers defining an object to be printed.

DETAILED DESCRIPTION

[0013] In the following description, numerous details are set forth to provide an

understanding of the examples disclosed herein. However, it will be understood that the examples may be practiced without these details. While a limited number of examples are disclosed, it should be understood that there are numerous modifications and variations therefrom.

[0014] As set forth above, there are some conventional solutions for processing information in a 3D data file as well as to enable a user to define how an object should be manufactured using a 3D printing system. Some of these conventional solutions enable a user to set some print settings for an object to be printed by a 3D printing system. However, conventional solutions still limit user flexibility at the time of defining how an object is to be printed.

[0015] Various examples described below are to facilitate a user defining how an object is to be printed by a 3D printing system. More specifically, some implementations of examples enable a user to select a print setting specifically for a portion of an object to be printed by a 3D printing system. Some implementations include

(i) identifying a print setting selected by a user specifically for a portion of an object to be printed by a 3D printing system, and

(ii) associating the selected print setting with the object portion.

[0016] More specifically, examples described herein facilitate specifying different print settings to different portions of an object to be printed, such as portions of the object body or specific surfaces of the object. Thereby, different print settings may be selectively applied when the object is being built by a 3D printing system. Such a specific selection of a print setting facilitates manufacturing objects with an increased functionality and efficiency as well as improved appearance using a 3D printing system. Generally, the print settings that can be specifically selected may depend on the particular printing method to be used to build the object.

[0017] As used herein, an object refers to a 3D object to be individually built, or actually built, by a 3D printing system. An object, as referred herein, is built by successively adding layers so as to form an integral piece. The GUI may render the object from a 3D model for enabling user definition of the object portion. By way of example, a 3D model may include a polygon mesh defining an object. A polygon mesh refers to a collection of vertices, edges, and faces defining the shape of a polyhedral object in a 3D model. The faces may be formed as polygons such as, but not limited to, triangles. Some 3D printing systems are capable of building, as part of the same print job, a plurality of independent pieces from a 3D model including a plurality of independent 3D objects (i.e., a collection of polygon meshes). An object may include void spaces embedded in the object body.

[0018] As used herein, a print setting refers to a parameter, or set of parameter, that defines how an object is to be printed by a 3D printing system. The print setting may include a parameter set corresponding to one or more physical properties of the object portion such as, but not limited to, density. Such a specific selection of density is particularly convenient to enhance functionality of a printed abject as well as facilitate efficient manufacturing as illustrated with respect to the example of FIG. 8. Further properties that may be user selected for a specific object portion includes material, color, roughness, or imperviousness.

[0019] Some implementations of examples may be operated as follows. A user may first define an object portion forming part of an object through a graphical user interface (GUI) (an example thereof being illustrated below with respect to FIGS. 7A-7B). After the user defines the object portion, the user may select a print setting specifically for that portion. After user selection of a print setting, a dedicated system (e.g., a computer system operatively coupled to a 3D printer) may identify the user selected setting and associate the user selected setting to the object portion. Thereby, the dedicated system may then generate a print job that takes into account these settings. Finally, the dedicated system may cause a 3D printing system to print the object according to the print setting selected by the user. An object is thereby created by layering and connecting successive cross-sections of material. The layer thickness may be in the range below 1 mm such as down to 0.25 mm or 0.1 mm or even further below. Horizontal resolution (i.e., across a layer) may be comparable to that of laser printers.

[0020] The following description is broken into sections. The first, labeled "Environment," describes an exemplary environment in which various examples may be implemented. The second section, labeled "Components," describes examples of various physical and logical components for implementing various examples. The third section, labeled as "Operation," describes steps taken to implement various examples.

[0021] ENVIRONMENT: FIG. 1 is a schematic diagram of an environment 10 in which various examples may be implemented. In environment 10, a print setting selection system 100 is communicatively coupled to a computer aid design (CAD) system 102 for receiving 3D model data 104. 3D model data 104 is associated with a 3D model 118 that includes an object 106 to be printed. 3D model 118 may include more than one object to be printed by a 3D printing system.

[0022] Print setting selection system 100 can be accessed by a user 108 for selecting a print setting specifically for an object portion (e.g., an object portion 116) of object 106. Object portion 116 is illustrated as an internal sub-volume of object 106. An object portion may also include one or more surfaces of an object as well as surface portions. Print setting selection system 100 is communicatively coupled to a 3D printing system 110 for printing object 106 according to the print setting selected by user 108. More specifically, print setting selection system 100 may generate a print job 112 for printing object 106. Print job 112 includes print data that takes into account the print settings specifically selected for object portion 116. Print setting selection system 100, CAD system 102, and 3D printing system 110 may be connected via a link (not shown in this Figure; the link may be analogous to link 424 shown in FIG. 4).

[0023] Print setting selection system 100 represents, generally, any computing device or combination of computing devices configured to enable a user to select a print setting specifically for a portion of an object to be printed by a 3D printing system. For example, but not limited thereto, print setting selection system 100 may operate a GUI to facilitate user selection of a print setting for an object portion. The GUI may include graphical elements such as windows, menus, buttons, dialogs or the like configured to allow a user to specifically select a print setting for object portion 116 (or any object portion of an object). A GUI for defining an object portion facilitates efficiently modifying the design of the object to be printed without affecting the main 3D geometry. User 108 may interact with print setting selection system 100 directly or through a computer terminal communicatively coupled thereto (e.g. the computer terminal may connected through the internet to print setting selection system 100). [0024] According to some examples, print setting selection system 100 may be configured to (i) identify a print setting selected by user 108 specifically for a portion of object 106 to be printed by 3D printing system 110; and (ii) associate the selected print setting with the object portion. For example, print setting selection system 100 may process data associated with 3D model 118, which includes object 106. Object 106 includes a spatially defined object portion 116. Print setting selection system 100 may enable user 108 to select a print setting specifically for object portion 116. Upon user selection, print setting selection system 100 may identify the user print selection for object portion 116. Further, print setting selection system 100 may process print setting data associated with 3D model 118 including the print setting specifically selected for 116. Print setting selection system 100 may modify a tangible readable medium (e.g., by generating or modifying a file) to register print setting data. Thereby, data related to the print setting specifically selected for object portion 116 may be tagged with a tag indicating a geometrical correspondence with object portion 116 so as to associate the specifically selected print setting with object portion 116. [0025] In some examples herein, print setting selection system 100 is configured to enable user 108 to define object portion 116 through a graphical user interface (GUI), such as GUI 700 illustrated below with respect to FIGS. 7A-7B. For performing this task, print setting selection system 100 may be configured to receive 3D model data 104 corresponding to 3D model 118 including object 106. More specifically, user 108 may load 3D model 118 in print setting selection system 100, 3D model 118 being generated or stored using CAD system 102.

Previously, 3D model 118 may have been created using CAD system 102 (or any other suitable system, which might be implemented in print setting selection system 100), as further detailed below. In the illustrated example, the loaded 3D model would be described by 3D model data 104, which is received by print setting selection system 100. Print setting selection system 100 may render the 3D model in the GUI, giving user 108 the capability to spatially define an object portion in object 106. User 108 may define the object portion by drawing a geometrical shape in the 3D model rendered by print setting selection system 100. In alternative examples, 3D model data 104 may already include a definition of an object portion so that object portion 116 is already defined in the 3D model rendered by print setting selection system 100; user 108 may then specifically select the print setting for the already defined object portion through print setting selection system 100.

[0026] According to some examples, print setting selection system 100 may be configured to define a stitching boundary region between object portions. More specifically, such a stitching boundary region may be associated with a varying print setting to smoothly interconnect adjacent object portions associated with different print settings. For example, adjacent object portions may be associated with different densities; without a stitching region, there may be an abrupt density change at the boundary between these adjacent object portions; for certain materials and/or density values, an abrupt density change may promote material fatigue; a stitching region defining a gradient of density that smoothly interconnect these object portions may prevent such an abrupt density region and, therefore, material fatigue at boundaries between object regions.

[0027] Print setting selection system 100 may be further configured to cause 3D printing system 110 to print object 106 according to the print setting selected by the user. More specifically, print setting selection system 100 may run a printing application (or a plug-in) that accepts as input a 3D model 118' with associated print settings (including specifically selected print settings for object portion 116). This data may be stored in a suitably formatted file or in a plurality of inter-referenced files (e.g., a file may contain spatial data of object 106, another file may contain spatial data of object portion 116, and another file may contain print settings for object 106 and object portion 116). Such a file may be structured as follows: Object 1 Tag

{object spatial data;

object print settings;

object portion 1 spatial data;

object portion 1 print setting; object portion N spatial data;

object portion N print setting}

Object K Tag

{object K spatial data;

object K print settings;

object portion 1 spatial data;

object portion 1 print setting; object portion M spatial data;

object portion M print setting)

It will be understood that the above file structure is merely illustrative and that there are a variety of file structures that are suitable for storing object information.

[0028] Print setting selection system 100 may generate from the printable 3D object model a print job with print settings associated to object portion 116 based on the specifically selected print setting. In some cases, it might be required that print setting selection system 100 transform object geometrical data into a valid printable 3D object model. Generally, how object geometrical data is transformed depends on the particular type of 3D printing system to print object 106. Examples of transformation of a 3D object model into a valid printable 3D object model are illustrated in the US application with application serial number US2011/0087350, which is incorporated herein by reference to the extent in which this document is not inconsistent with the present disclosure, and in particular those parts thereof describing transformation of 3D models into a valid printable model.

[0029] In the depicted example, print setting selection system 100 is shown deployed as part of a cloud computing system 120 (hereinafter referred to as cloud 120). A cloud computing system refers to a computing system including multiple pieces of hardware operatively coupled over a network so that they can perform a specific computing task. In the illustrated

embodiment, cloud 120 includes a combination of physical hardware, software, and virtual hardware (not shown) configured to implement print setting selection system 100 or, in other words, to implement the functionality of print setting selection system 100 as set forth herein. User 108 may interact with print setting selection system 100 through a computer connected to internet (e.g., through CAD system 102 or another computing system). In other examples, user

108 may directly interact with print setting selection system 100.

[0030] CAD system 102 represents, generally, any computing device or combination of computing devices configured to provide a 3D model (e.g., 3D model 118) that includes one or more objects (e.g., object 106) to print setting selection system 100. CAD system 102 may be a computer system equipped with CAD software suitable for building a 3D model 104 of an object to be printed. Examples of such CAD software include AutoCad®, Revit®, or SolidWorks®. User 108 may interact with CAD system 102 for creating models of objects such as object 106. CAD system 102 may store data 104 associated with 3D model 118 as forming part of a geometry definition data file containing 3D model data 104.

[0031] Such a geometry definition data file may be constructed using a variety of file formats. For example, such a geometry definition data file may correspond to a file format specifically designed for 3D printing such as stereolithography (.stl) file format, polygon file format (.ply), or additive manufacturing file (.amf) format. CAD system 102 may send 3D model data 104 to print setting selection system 100 by sending a geometry definition data file containing 3D model data 104. According to some examples, CAD system 102 may be configured to enable a user to define an object portion (e.g., object portion 116). In such examples, CAD system 102 may embed data corresponding to the user definition of the object portion within a geometry definition data file formatted to include data corresponding to a geometrical definition of an object portion. In some examples, a 3D model may be created using a computer system independent from CAD system 102. CAD system 102 may be then used merely for storing the 3D model and providing the 3D model to print setting selection system 100.

[0032] In environment 10, print setting selection system 100 and CAD system 102 are illustrated as independent computing systems. Print setting selection system 100 and CAD system 102 may be combined in a single system responsible for generating and processing 3D model data 104 as illustrated above for enabling a specific selection of a print setting of an object portion. Moreover, the software functionality illustrated above may be combined in a single software application. For example, conventional software for development of 3D models may provide services for the implementation of plug-in modules that enable further functionality of the application. A set of plug-in modules may be developed for one of the above referred to CAD software applications, the set of plug-in implementing the functionality of print setting selection system 100 illustrated above. In other examples, at least some of the functionality of print setting selection system 100 described above may be implemented as a stand-alone application.

[0033] Printing system 110 represents, generally, any system for additive manufacturing of an object. Printing system 110 may use a transformation of object 106 as defined in 3D model 118' into relatively thin horizontal cross-sections (not shown) and then create successive layers (see, e.g., FIG. 9) until object 106 is reproduced. For example, 3D printing system 110 may be configured to implement fused deposition modeling (FDM) in which a nozzle arrangement is arranged to deposit a molten thermoplastic material onto a support structure, layer by layer. Alternatively, 3D printing system 110 may be configured to implement other additive

manufacturing methods such as, but not limited to, inkjet printing, digital light processing (DLP), or stereolithography. For implementing inkjet printing, 3D printing system 110 may be configured to spread a resin layer and inkjet printing a binder in the cross-section of the object, the process being repeated layer by layer for forming the object. For implementing DLP, 3D printing system 110 may be configured to partially expose a vat of liquid polymer to light from a DLP projector (liquid exposed to DLP light hardens). More specifically, successive layers of the liquid polymer may be exposed to DLP light until the object is formed. Remaining liquid polymer may be evacuated from the vat to leave a solid reproduction of the object. For implementing stereolithography, 3D printing system 110 may be configured to deposit (e.g., by inkjet printing) resin layers and partially cure the deposited resin layers using a laser or, more specifically a UV laser, so as to solidify the resin volume that corresponds to the object to be printed.

[0034] As already set forth above, it is contemplated to implement user selection of print setting in a variety of environment alternative to environment 10. In particular, at least some of the functionality illustrated above with respect to print setting selection system 100 and CAD system 102 may be implemented in a single dedicated computing system.

[0035] According to some examples, at least some of the functionality illustrated above with respect to print setting selection system 100 and CAD system 102 may be deployed in a cloud environment accessible by user 108. In this case, user 108 may accede to the functionality set forth above as an online service. The online service may enable to upload a 3D geometry definition data file; alternatively or in addition thereto, the online service may include a module for enabling the user to generate a 3D model including one or more objects to be printed.

Further, the online service may include a print setting selection engine (such as engine 202 illustrated below with respect to FIG. 2) for enabling a user to select a print setting specifically for a portion of an object to be printed by a 3D printing system. The online service may also include a printing engine (such as engine 214 illustrated below with respect to FIG. 2) to cause 3D printing system 110 to print an object according to the print setting selected by user 108. Further, the online service may collect data from user 108 for automatically billing and sending the manufactured object. As an alternative to an online service, the dedicated computing system may be deployed on premise, i.e., run on computers in the premises of user 108.

[0036] In some other examples, at least some of the functionality illustrated above with respect to print setting selection system 100 and CAD system 102 may be integrated into 3D printing system 110. In such examples, 3D printing system 110 may include a user console for facilitating interaction with user 108. [0037] COMPONENTS: FIGS. 2-6 depict various examples of physical and logical

components for implementing various examples. FIG. 2 depicts a system 200 for causing printing of a 3D object. In the example of FIG. 2, system 200 includes a print setting selection engine 202 and, optionally, one or more of the following engines: a model receiving engine 204, an object portion specification engine 206, and a printing engine 214. By way of example and referring back to environment 10 illustrated with respect to FIG. 1, system 200 may be implemented as forming part of print setting selection system 100.

[0038] Print setting selection engine 202 represents generally any combination of hardware and programming configured for enabling a user (e.g., user 108) to select a print setting specifically for a portion of an object (e.g., an object included in 3D model 118) to be printed by a 3D printing system (e.g., 3D printing system 110). Print setting selection engine 202 may perform this task by operating a GUI (e.g. GUI 700 illustrated with respect to FIGS. 7A and 7B). The user may interact with the GUI to select a print setting (e.g., density, material, color, roughness, imperviousness, or a selection thereof) specifically for an object portion.

[0039] Spatial data of an object may be stored in data store 210 as part of 3D model data 212. 3D model data 212 may include also spatial data of an object portion. Further, print setting selection engine 202 may store a print setting specifically selected by a user in data store 210 as part of print setting data 208. Print setting data 208 and 3D model data 212 may be stored in data store 210 using any suitable file format. More specifically, print setting data 208 and 3D model data 212 may be stored using a data file system including one or more files. By way of example, print setting data 208 and 3D model data 212 may be stored in respective files; 3D model data 212 may be stored in a geometry definition data file suitable to store spatial data of objects and object portions; print setting data 208 may be stored in a print setting data file suitable to store print setting; these files may be inter-referenced (e.g., using tags included in one or both of the files). According to other examples, print setting data 208 and 3D model data 212 may be stored in a single file (such a file may be structured as illustrated above with respect to FIG. 1).

[0040] Print setting selection engine 202 may be further configured to (i) identify a print setting selected by the user specifically for an object portion, and, once a print setting selection is identified, (ii) associate the selected print setting with the object portion. For example, print setting selection engine 202 may process data associated with a 3D model, which includes an object with a spatially defined object portion. Print setting selection engine 202 may be further configured to detect a user selection of a print setting specific for the object portion and associate that user selection to the corresponding object portion. Print setting selection engine 202 may maintain the association between the specifically selected print setting and the corresponding object portion by inter-referencing portions of print setting data 208 and 3D model data 212 using a data file system as illustrated above.

[0041] A specifically selected print setting may include a parameter set corresponding to one or more physical properties of the object portion. A physical property refers to a property pertaining to construction of the object, which property is defined during manufacturing of the object by a 3D printing system. In some examples, the parameter set may include density, material, color, roughness, imperviousness, or a selection thereof. Object density may correspond to planar density (mass per unit area) or volume density (mass per unit volume). Selection of density may be convenient for manufacturing an object with enhanced functionality as illustrated with respect to FIG. 8. Object material refers to the material processed by a 3D printing system to manufacture an object portion. By way of example, object material may include thermoplastic material such as a molten polymer or any other material suitable for 3D printing. Imperviousness refers to the property of preventing flow of a fluid through an object portion. An object portion might be manufactured watertight by manufacturing that object portion with a watertight material at a sufficiently high density. By way of example, print setting selection engine 202 may enable to manufacture an object with watertight surfaces by, for example, building the external surfaces of the object with a watertight material and the body of the object with a different material, which is not necessarily watertight.

[0042] Model receiving engine 204 represents, generally, any combination of hardware and programming configured for receiving data corresponding to an object. For example, model receiving engine 204 may be configured to receive data generated by a CAD system (e.g., CAD system 102 illustrated with respect to FIG.1), the data corresponding to a 3D model that includes one or more objects. In some examples, model receiving engine 204 may be configured to obtain data corresponding to an object from a 3D geometry definition data file. Such a 3D geometry definition data may be generated by a CAD system as illustrated above with respect to FIG. 1. The received data may be stored as part of 3D model data 212 and be used or updated for selectively specifying a print setting as described herein.

[0043] Object portion specification engine 206 represents, generally, any combination of hardware and programming configured for enabling a user to geometrically define an object portion. More specifically, object portion specification engine 206 may be configured to enable a user to define an object portion through a GUI. Such a GUI may include controls configured to enable a user to geometrically define the spatial location of an object control as illustrated below with respect to FIGS. 7A-7B. Object portion specification engine 206 may enable a user to define the object portion by drawing the object portion in a 3D model rendered from a 3D geometry definition data file. For example, object portion specification engine 206 may process a 3D geometry definition data file (e.g., a .stl file) to access data corresponding to a 3D model with one or more objects. Object portion specification engine 206 may process the accessed data to render the 3D model (and, more specifically, one or more objects included in the 3D model) in a particular graphical environment such as GUI 700. Object portion specification engine 206 may operate a set of GUI controls (e.g., controls 704a-704f, depicted in FIGS. 7A-7B) to facilitate a user defining an object portion of one object in the rendered 3D model.

[0044] Printing engine 214 represents generally any combination of hardware and programming configured for causing a 3D printing system to print an object according to a print setting selected by a user. For example, printing engine 214 may generate a print job that takes into account a specifically selected print setting. The print job is formatted according to the particular printing system to print the object. Printing engine 214 may be configured to generate a print job with printer commands defining the shape of the successive layer to manufacture an object as well as the physical properties of the successive layers. The defined physical properties within a single layer may vary such that portions of the successive layers reproduce an object portion with a specifically selected print portion, as illustrated with respect to FIG. 9.

[0045] FIG. 9 schematically depicts a cross section 900 of successive layers 902a-902h defining an object 904 to be printed. Object 904 includes an object body inner portion 906 to be printed with a higher density than an object body outer portion 908. Further, object 904 includes a through hole 910. For manufacturing object 904, printing engine 214 may generate a print job including instructions that cause a print system to form each of layers 902a-902i with (a) layer portions 912a-912i, 914a-914i, corresponding to object body outer portion 908, with a first density, and (b) layer portions 916a-916i, 918a-918i, corresponding to object body inner portion 906, with a second density. [0046] As it will be understood, how the instructions are generated for printing different portions of an individual layer with different physical properties depends, among other factors, on the particular 3D printing system to be used for manufacturing an object as described herein.

By way of example, regarding the use of a FDM printing system for manufacturing object 904, printing engine 214 may generate instructions that cause a FDM printing system to adjust the flow of deposited molten thermoplastic material for forming a layer such that each layer portion is formed with the selected density. In a further example, a 3D printing system may be configured for printing using different materials (e.g., a FDM printing system could be provided with multiple material outlets, each outlet being configured to deposit a different material); printing engine 214 may be configured to generate instructions that cause such a 3D printing system to operate a particular nozzle for forming a layer portion according to a material specifically selected for a corresponding object portion.

[0047] In the foregoing discussion, various components were described as combinations of hardware and programming. Such components may be implemented in a number of fashions. Referring to FIG. 3 the programming may be processor executable instructions stored on tangible memory media 302 and the hardware may include a processor 304 for executing those instructions. Memory 302 can be said to store program instructions that when executed by processor 304 implement system 200 of Fig. 2. Memory 302 may be integrated in the same device as processor 304 or it may be separate but accessible to that device and processor 304. [0048] In examples, the program instructions can be part of an installation package that can be executed by processor 304 to implement system 200. In such examples, memory 302 may be a portable medium such as a CD, DVD, or flash drive or a memory maintained by a server from which the installation package can be downloaded and installed. In another example, the program instructions may be part of an application or applications already installed. Here, memory 302 can include integrated memory such as a hard drive.

[0049] In FIG. 3, the executable program instructions stored in memory 302 are depicted as a print setting selection module 306 and, optionally, one or more of the following modules: a model receiving module 308, an object portion specification module 310, and a printing module 312. Print setting selection module 306 represents program instructions that when executed cause the implementation of print setting selection engine 202 of FIG. 2. Likewise, model receiving module 308, represents program instructions that when executed cause the

implementation of model receiving engine 204. Likewise, object portion specification module 310 represents program instructions that when executed cause the implementation of object portion specification engine 206. Likewise, printing module 312 represents program instructions that when executed cause the implementation of printing engine 214.

[0050] As a further example, FIG. 4 depicts a block diagram of system 200 implemented by print setting selection system 100. In the example of FIG. 4, CAD system 102 is shown to include memory 402, processor 404, and interface 406. Processor 404 represents, generally, any processor configured to execute program instructions stored in memory 402 to perform various specified functions. Interface 406 represents, generally, any interface enabling CAD system 102 to communicate at least with print setting selection system 100 via link 424.

[0051] Memory 402 is shown to include an operating system 408 and applications 410.

Operating system 408 represents a collection of programs that when executed by processor 404 serve as a platform on which applications 410 can run. Examples of operating systems include, but are not limited, to various versions of Microsoft's Windows® and Linux®. Applications 410 represent program instructions that when executed by processor 404 function as an application that provides 3D model data to print setting selection system 100. Applications 410, when executed, may also function as a service that enables a user to generate or modify 3D model data.

[0052] Print setting selection system 100 is shown to include memory 412, processor 414, and interface 416. Processor 414 represents generally any processor configured to execute program instructions stored in memory 412 to perform various specified functions. Interface 416 represents generally any interface enabling print setting selection system 100 to communicate with CAD system 102.

[0053] Memory 412 is shown to include operating system 418 and applications 420.

Operating system 418 represents a collection of programs that when executed by processor 414 serve as a platform on which applications 420 can run. Examples of operating systems include, but are not limited, to various versions of Microsoft's Windows® and Linux®. Applications 420 represent program instructions that when executed by processor 414 implement system 200 for enabling a user to specifically select a print setting for an object portion as discussed above with respect to FIG. 2.

[0054] The components in FIG. 4 interact with each other through a link 424 that represents, generally, one or more of a cable, wireless, fiber optic, or remote connections via a

telecommunication link, an infrared link, a radio frequency link, or any other connectors or systems that provide electronic communication. Link 424 may include, at least in part, an intranet, the Internet, or a combination of both. Link 424 may also include intermediate proxies, routers, and/or switches. [0055] Referring back at FIG. 2, print setting selection engine 202, model receiving engine

204, object portion specification engine 206, and printing engine 214 are described a

combinations of hardware and programming. The hardware portions may, depending on the example, be implemented as processor 414. The programming portions, depending on the example, can be implemented by operating system 422, applications 420, or combinations thereof.

[0056] As already mentioned above, alternative environments to the examples depicted in FIGS. 1 or 4 are contemplated. For example, the functionality of CAD system 102 and system 200 may be combined on a single system that is configured to, additionally to the functionalities provided by print setting selection engine 202 (and, optionally, model receiving engine 204, object portion specification engine 206, and/or printing engine 214), generate, modify or store 3D model data. Further, a 3D printing system may include a processor, an interface and a memory configured to implement the functionality of system 200 and, optionally, CAD system 102 as illustrated above. [0057] OPERATION: FIGS. 5A-6 are flow diagrams that implement examples of methods for 3D printing of an object. In discussing FIGS. 5A-6 reference is made to the diagrams of

FIGS. 7A-8 to provide contextual examples. Implementation, however, is not limited to those examples.

[0058] Referring to FIG. 5A, a flow diagram 500 includes identifying 502 a print setting selected by a user specifically for a portion of an object to be printed by a 3D printing system.

Referring back to FIG. 2, print setting selection engine 202 may be responsible for implementing block 502.

[0059] FIG. 6 depicts a process flow for implementing block 502. Data corresponding to a 3D model may be received at block 602 before identifying 502 a specifically selected print setting. Block 602 may include obtaining 604 data from a 3D geometry definition file (e.g., a .stl file, a .ply file, or a .amf file) as illustrated above with respect to FIG. 1. Referring back to FIG. 2, model receiving engine 204 may be responsible for implementing block 602.

[0060] Further, also before identifying 502 a specifically selected print setting, a user definition of an object portion may be received at block 606. The user definition may be included in the 3D geometry definition data file of block 604. Alternatively, block 606 may include enabling 608 a user to geometrically define an object portion through a GUI such as GUI 700 illustrated below with respect to FIGS. 7 A and 7B. Upon user definition of an object portion, block 606 may include detecting 610 an object portion definition in the GUI. [0061] Block 502, in which a specifically selected print setting is received, may include receiving 612 a user selection of a print setting specific for an object portion. Block 612 may include enabling 614 a user selection of a print setting for an object portion. Block 614 may be implemented by operating a GUI including controls that enable a user to define a print setting specifically for an object portion as illustrated with respect to FIGS. 7A-7B below. Upon user specific selection of a print setting for an object portion, block 612 may include detecting 616 the specifically selected print setting.

[0062] Referring back to FIG. 5A, flow diagram 500 may further include associating 504 the print setting identified in block 502 with the corresponding object portion. Referring back to FIG. 2, print setting selection engine 202 may be responsible for implementing block 504. For example, print setting selection engine 202 may inter-reference data in print setting data 208 and 3D model data 212 for associating a print setting with a corresponding object portion.

[0063] Flow diagram 500 may further include generating 506 a print job for printing a 3D model with the print setting specifically selected at block 502. Further, flow diagram 500 may further include causing 508 a 3D printing system to print the print job generated at block 506. Referring back to FIG. 2, printing engine 214 may be responsible for implementing blocks 506 and 508 in the manner illustrated above with respect to FIGS. 1 and 2.

[0064] FIG. 5B is a further flo w diagram 510 that implement examples of methods for 3D printing of an object. At block 512, a print setting is received, the print setting being selected by a user specifically for a portion of an object. At block 514, the received print setting is associated with the object portion. Referring back to FIG. 2, model receiving engine 204 may be responsible for implementing flow diagram 510.

[0065] FIGS. 7 A and 7B illustrate a GUI 700 for specifically selecting a print setting for an object portion that can be operated according to the flow diagrams depicted in FIGS. 5A-6. The system depicted in FIG. 2 may be responsible for operation of GUI 700 (however, it will be understood that system 200 is not necessarily limited to operation of a GUI). Operation of GUI 700 is illustrated for manufacturing object 800 depicted in FIG. 8.

[0066] Before describing further details regarding GUI 700, design of object 800 is described for providing a contextual example. Design of object 800 using a specific selection of a print setting for an object portion illustrates the convenience of examples described herein. More specifically, the example of FIG. 8 illustrates the convenience of specifically selecting density of an object portion: a specific selection of density may conveniently enhance functionality of a printed abject as wells as facilitate efficient object manufacturing. By way of example, an object with a light body and reinforced sections may be built by specifically selecting high density as a print setting for the reinforced sections. Although not illustrated in the following example, print settings may be specifically selected for surfaces of an object. For instance, using examples herein, an object may be built with reinforced surfaces by specifically selecting high density as print setting for the object surfaces and low density as print setting for the object body thus enabling good surface quality and fast print time.

[0067] The design goal for manufacturing object 800 illustrated in FIG. 8 is to design a parallelepiped 802, with a hole 804 formed at a central portion thereof. Further, it is intended that hole 804 can receive a screw therein. Therefore, it is required that an internal thread can be generated at the interior walls of hole 804 after manufacturing object 800. Thread generation poses a specific robustness requirement in the manufacturing of object 800 (if the central portion of the manufactured object is not sufficiently robust, it may break during thread generation). Further, as it will be understood, it is desirable to manufacture object 800 with a minimum of material usage but satisfying design requirements.

[0068] Design of a manufactured object may start from 3D model 806, which includes an object formed by parallelepiped 802 and hole 804. FIG. 8 illustrates cross-sections of objects 800, 808, 810. Objects 808, 810 illustrate manufactured objects using conventional techniques for 3D printing, which, for the sake of illustration, do not provide for a specific selection of a print setting for an object portion. Therefore, design of the object bodies of objects 808 and 810 is restricted to a uniform density. More specifically, object 808 is designed with a relatively high density of object body 812 to provide a robustness sufficient to enable generating a thread at the interior wall of hole 804. However, design of object 808 requires a relatively high material usage as well as a relatively high object weight. Object 810 is designed with a relatively low density of object body 810 to keep material usage and object weight low. However, due to its low body density, design of object 810 increases the risk of object breakage during generation of a thread at the interior wall of hole 804.

[0069] In contrast to design of objects 808 and 810, the specific selection of a print setting for an object portion described herein facilitates a design of the object body of object 800 with different densities so as to allow meeting the particular design requirements mentioned above, namely robustness and low material usage and object weight. More specifically, object 800 is designed by specifically selecting different densities for different portions of object body 810: a print setting with a relatively low density is chosen for an outer body portion 812a and a print setting with a relatively high density is chosen for an inner body portion 812b. Inner body portion 812b provides a robustness sufficiently high to prevent object breakage during generation of a thread at the interior wall of hole 804. The relatively low density of outer body portion 812a facilitates keeping low material usage and object weight.

[0070] Referring back to FIGS. 7A-7B, GUI 700 is to enable specifically selection of a print setting for an object portion, such as outer body portion 812a and inner body portion 812b. In the illustrated example, GUI 700 also enables a user to geometrically define an object portion. In other examples, a GUI may be limited merely to enable a user to specifically select a print setting for an object portion that is already geometrically defined using another application.

[0071] GUI 700 includes a drawing panel 704, a print setting panel 706, and a 3D model panel 708. 3D model panel 708 is to display a 3D model including one or more objects. In the illustrated example, 3D model panel 708 displays 3D model 806 also depicted in FIG. 8. 3D model 806 includes an object 710 formed by parallelepiped 802 and hole 804. FIG. 7A depicts 3D model 806 before an object portion 712 (see FIG. 7B) is geometrically defined in object 710.

[0072] Drawing panel 704 includes a set of tools that enable a user to geometrically define an object portion in an object included in a 3D model displayed in 3D model panel 708. In the illustrated example, drawing panel 704 includes a plurality of buttons 704a-704g that enable a user to draw forms in 3D model panel 708 to define an object portion (e.g., object portion 712). Upon pushing one of the buttons, GUI 700 allows a user to draw a specific geometric shape in 3D model panel 708 such as a rectangle (button 704a), an ellipse (button 704b), a line (button 704c), a curve (button 704d), or a free form (button 704e). 3D model panel 708 may include other controls commonly found in a CAD graphical interface to facilitate a user to draw 2D or 3D shapes. The drawn shapes may be combined so as to define an object portion.

[0073] Print setting panel 706 includes controls configured for defining a print setting of an object or of an object portion. In the illustrated example, print setting panel 706 includes a tab 706a for defining a default print parameters of object 710. Tab 706a includes forms 714a-714e to individually define parameters of a default print parameters of object 710. In the shown example, forms 714a-714e enable defining by default the following parameters of an object: material (form 714a), density (form 714b), color (form 714d), roughness (form 714d), and imperviousness (form 714e).

[0074] GUI 700 is configured to generate a new tab in print setting panel 706 for each defined object portion. As illustrated in FIG. 7B, upon definition of object portion 712, a new tab 706b is created that enables specifically selecting print setting 702 for object portion 712. In the illustrated example, tab 706b includes forms 714a'-714e' analogous to those of tab 706a. Once an object portion is generated, a user may individually define the print parameters for that portion. As illustrated, GUI 700 enables a user to realize the object design described above with respect to FIG. 8 by defining a density for object portion 712 (corresponding to inner body portion 812b) higher than the default density (corresponding to outer body portion 812a)

[0075] CONCLUSION: Figs. 1-4 aid in depicting the architecture, functionality, and operation of various examples. In particular, Figs. 2-4 depict various physical and logical components. Various components illustrated in Fig. 2-4 are defined at least in part as programs, programming, or program instructions. Each such component, portion thereof, or various combinations thereof may represent in whole or in part a module, segment, or portion of code that comprises one or more executable instructions to implement any specified logical function(s). Each component or various combinations thereof may represent a circuit or a number of interconnected circuits to implement the specified logical function(s).

[0076] Embodiments can be realized in any computer-readable media for use by or in connection with an instruction execution system such as a computer/processor based system or an ASIC (Application Specific Integrated Circuit) or other system that can fetch or obtain the logic from computer-readable media and execute the instructions contained therein. "Computer- readable media" can be any media that can contain, store, or maintain programs and data for use by or in connection with the instruction execution system. Computer readable media can comprise any one of many physical media such as, for example, electronic, magnetic, optical, electromagnetic, or semiconductor media. More specific examples of suitable computer- readable media include, but are not limited to, a portable magnetic computer diskette such as floppy diskettes or hard drives, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory, or a portable compact disc.

[0077] Although the flow diagrams in FIGS. 5A-6 show specific orders of execution, the order of execution may differ from that which is depicted. For example, the order of execution of two or more blocks may be scrambled relative to the order shown. Also, two or more blocks shown in succession may be executed concurrently or with partial concurrence. All such variations are contemplated.

[0078] In the foregoing description, numerous details are set forth to provide an

understanding of the examples disclosed herein. However, it will be understood that the examples may be practiced without these details. While a limited number of examples have been disclosed, numerous modifications and variations therefrom are contemplated. For example, a 3D printing system is contemplated that includes a system as described above with respect to FIGS. 2 and 3. It is intended that the appended claims cover such modifications and variations. Claims reciting "a" or "an" with respect to a particular element contemplate incorporation of one or more such elements, neither requiring nor excluding two or more such elements. Further, the terms "include" and "comprise" are used as open-ended transitions.

Claims

CLAIMS What is claimed is:

1. A non-transitory tangible computer readable storage medium comprising instructions that, when executed by a computer, cause the computer to: identify a print setting selected by a user specifically for a portion of an object to be printed by a 3D printing system; and associate the selected print setting with the object portion.

2. The medium of claim 1, wherein the print setting includes a parameter set corresponding to one or more physical properties of the object portion.

3. The medium of claim 2, wherein the parameter set includes density, material, color, roughness, imperviousness, or a selection thereof.

4. The medium of claim 1, further comprising instructions to obtain data corresponding to said object from a 3D geometry definition data file.

5. The medium of claim 1, further comprising instructions to enable a user to define the object portion through a graphical user interface.

6. The medium of claim 5, further comprising instructions to enable the user to define the object portion by drawing the object portion in a three-dimensional model rendered from a 3D geometry definition data file.

7. The medium of claim 1, further comprising instructions to cause a 3D printing system to print said object according to the print setting selected by the user.

8. A system comprising a print setting selection engine for enabling a user to select a print setting specifically for a portion of an object to be printed by a 3D printing system.

9. The system of claim 8, further comprising a receiving engine for receiving data corresponding to said object.

10. The system of claim 8, further comprising an object portion specification engine to enable a user to define the object portion.

11. The system of claim 8, further comprising a printing engine to cause a 3D printing system to print said object according to the print setting selected by the user.

12. The system of claim 8, further comprising a 3D printing system to print said object according to the print setting selected by the user.

13. A method for three-dimensional printing of an object, the method including: receiving a print setting selected by a user specifically for a portion of said object; and associating the received print setting with the object portion.

14. The method of claim 13, further including receiving a user definition of the object portion.

15. The method of claim 13, further including generating a print job for printing said object, the print job including print data according to the print setting for the object portion.

16. The method of claim 15, further including causing a 3D printing system to print the print job.