Abstract: A system and a method of mitigating color discrepancies in three-dimensional (3D) printing systems may including a plurality of printing heads may include: printing one or more samples according to one or more sample parameters; obtaining a color offset vector from the one or more samples; receiving a model representing a 3D object, the model comprising a plurality of model printing points associated with respective color; analyzing the model in view of the obtained color offset vector to produce a calibrated data structure, adapted to mitigate color discrepancies; and printing the 3D object according to the calibrated data structure.

Abstract: A method of printing a three-dimensional (3D) color object, layer-by-layer, comprises: obtaining a 3D CAD specification defining a 3D geometry and a surface color distribution for the color object to be printed, defining regions on a surface of the color object; defining colors for each region based on the CAD specification; determining, using the 3D geometry of the specification, conditions applying at respective regions that are liable to cause color variation, such that using the colors as defined at the respective regions may give rise to a coloration error; selecting color corrections defined for respective determined conditions; correcting the defined colors; and printing the 3D color object with the color corrections.

Abstract: Methods, particularly automated methods, are provided, as well as 3D-printed composite and hollow objects and 3D-printing systems for printing them. Methods comprise deriving a central line of a hollow 3D object model, calculating reference point(s) and/or line(s) along an inner surface of the hollow 3D object model, and filling the hollow 3D object model with material that comprises a thread defined with respect to the central line and the reference point(s) and/or line(s) and with filling material surrounding the thread. The support construction thus formed may be removed from the 3D object by pulling on the thread, extracting it and the surrounding support filling from the hollow object, thus enabling 3D-printing of convoluted or elongated hollow objects and objects with narrow openings. The parameters of the thread, such as type of curve and thickness, are selected to ensure thread extraction without risk of tearing or knotting the thread.

Abstract: A method of printing a three-dimensional (3D) object and a support construction for the 3D object includes depositing a model material, layer-by-layer, on a fabrication platform, to print a first portion of the 3D object, and depositing a support material, layer-by-layer on the fabrication platform, to print the support construction, wherein, in a predetermined number of the deposited layers, the model material and the support material are deposited such that a gap is formed between a surface of the first portion of the 3D object and a surface of the support construction.

Abstract: Methods and systems are disclosed for selecting a print head of a 3D printing machine to apply 3D printing material at one or more positions in a printed 3D object. Embodiments of the present invention may include, in the selection process one or more elements pertaining for example to: geometry of the received 3D model; colorization of the received 3D model; transparency of the received 3D model; properties of the 3D printing material; and constraints of the 3D printing machine.

Abstract: A method of processing data for additive manufacturing of a 3D object comprises: receiving graphic elements defining a surface of the object, and an input color texture to be visible over a surface of the object; transforming the elements to voxelized computer object data; constructing a 3D color map having a plurality of pixels, each being associated with a voxel and being categorized as either a topmost pixel or an internal pixel. Each topmost pixel is associated with a group of internal pixels forming a receptive field for the topmost pixel. A color-value is assigned to each topmost pixel and each internal pixel of a receptive field associated with the topmost pixel, based on the color texture and according to a subtractive color mixing. A material to be used during the additive manufacturing is designated based on the color-value.

Abstract: Methods and systems are disclosed for selecting a print head of a 3D printing machine to apply 3D printing material at one or more positions in a printed 3D object. Embodiments of the present invention may include, in the selection process one or more elements pertaining for example to: geometry of the received 3D model; colorization of the received 3D model; transparency of the received 3D model; properties of the 3D printing material; and constraints of the 3D printing machine.

Abstract: Methods and systems are provided, which convert points in a cloud into a model for 3D printing in a computationally efficient manner and while maintaining and possibly adjusting shape, volume and color information. Methods include deriving, from the points, a crude watertight mesh with respect to the points, e.g., an alpha shape, determining, using normal vectors associated with the points, locations of the points with respect to the mesh (e.g., as being inside, outside or within the model) and using the derived mesh to define the model with respect to the determined locations of the points. Combining the computational geometry approach with the field approach is synergetic and results in better information content of the resulting model for 3D printing while consuming less computational resources.

Abstract: A method of processing data for additive manufacturing of a 3D object comprises: receiving graphic elements defining a surface of the object, and an input color texture to be visible over a surface of the object; transforming the elements to voxelized computer object data; constructing a 3D color map having a plurality of pixels, each being associated with a voxel and being categorized as either a topmost pixel or an internal pixel. Each topmost pixel is associated with a group of internal pixels forming a receptive field for the topmost pixel. A color-value is assigned to each topmost pixel and each internal pixel of a receptive field associated with the topmost pixel, based on the color texture and according to a subtractive color mixing. A material to be used during the additive manufacturing is designated based on the color-value.

Abstract: Methods and systems are disclosed for selecting a print head of a 3D printing machine to apply 3D printing material at one or more positions in a printed 3D object. Embodiments of the present invention may include, in the selection process one or more elements pertaining for example to: geometry of the received 3D model; colorization of the received 3D model; transparency of the received 3D model; properties of the 3D printing material; and constraints of the 3D printing machine.

Abstract: A method of processing data for additive manufacturing of a 3D object comprises: receiving graphic elements defining a surface of the object, and an input color texture to be visible over a surface of the object; transforming the elements to voxelized computer object data; constructing a 3D color map having a plurality of pixels, each being associated with a voxel and being categorized as either a topmost pixel or an internal pixel. Each topmost pixel is associated with a group of internal pixels forming a receptive field for the topmost pixel. A color-value is assigned to each topmost pixel and each internal pixel of a receptive field associated with the topmost pixel, based on the color texture and according to a subtractive color mixing. A material to be used during the additive manufacturing is designated based on the color-value.

Abstract: An additive manufacturing method for printing an object includes receiving three-dimensional printing data corresponding to the object, defining an internal region of the object to be formed with a structured air pocket and printing the object with an additive manufacturing system. The object includes an internal region formed with a structured air pocket.

Abstract: A system and a method of mitigating color discrepancies in three-dimensional (3D) printing systems may including a plurality of printing heads may include: printing one or more samples according to one or more sample parameters; obtaining a color offset vector from the one or more samples; receiving a model representing a 3D object, the model comprising a plurality of model printing points associated with respective color; analyzing the model in view of the obtained color offset vector to produce a calibrated data structure, adapted to mitigate color discrepancies; and printing the 3D object according to the calibrated data structure.

Abstract: A method of processing data for additive manufacturing of a 3D object comprises: receiving graphic elements defining a surface of the object, and an input color texture to be visible over a surface of the object; transforming the elements to voxelized computer object data; constructing a 3D color map having a plurality of pixels, each being associated with a voxel and being categorized as either a topmost pixel or an internal pixel. Each topmost pixel is associated with a group of internal pixels forming a receptive field for the topmost pixel. A color-value is assigned to each topmost pixel and each internal pixel of a receptive field associated with the topmost pixel, based on the color texture and according to a subtractive color mixing. A material to be used during the additive manufacturing is designated based on the color-value.

Abstract: Methods, particularly automated methods, are provided, as well as 3D-printed composite and hollow objects and 3D-printing systems for printing them. Methods comprise deriving a central line of a hollow 3D object model, calculating reference point(s) and/or line(s) along an inner surface of the hollow 3D object model, and filling the hollow 3D object model with material that comprises a thread defined with respect to the central line and the reference point(s) and/or line(s) and with filling material surrounding the thread. The support construction thus formed may be removed from the 3D object by pulling on the thread, extracting it and the surrounding support filling from the hollow object, thus enabling 3D-printing of convoluted or elongated hollow objects and objects with narrow openings. The parameters of the thread, such as type of curve and thickness, are selected to ensure thread extraction without risk of tearing or knotting the thread.

Abstract: A method of printing a three-dimensional (3D) color object, layer-by-layer, comprises: obtaining a 3D CAD specification defining a 3D geometry and a surface color distribution for the color object to be printed, defining regions on a surface of the color object; defining colors for each region based on the CAD specification; determining, using the 3D geometry of the specification, conditions applying at respective regions that are liable to cause color variation, such that using the colors as defined at the respective regions may give rise to a coloration error; selecting color corrections defined for respective determined conditions; correcting the defined colors; and printing the 3D color object with the color corrections.

Abstract: A method of printing a three-dimensional (3D) object and a support construction for the 3D object includes depositing a model material, layer-by-layer, on a fabrication platform, to print a first portion of the 3D object, and depositing a support material, layer-by-layer on the fabrication platform, to print the support construction, wherein, in a predetermined number of the deposited layers, the model material and the support material are deposited such that a gap is formed between a surface of the first portion of the 3D object and a surface of the support construction.

Abstract: A method of printing a three-dimensional (3D) color object, layer-by-layer, comprises: obtaining a 3D CAD specification defining a 3D geometry and a surface color distribution for the color object to be printed, defining regions on a surface of the color object; defining colors for each region based on the CAD specification; determining, using the 3D geometry of the specification, conditions applying at respective regions that are liable to cause color variation, such that using the colors as defined at the respective regions may give rise to a coloration error; selecting color corrections defined for respective determined conditions; correcting the defined colors; and printing the 3D color object with the color corrections.

Abstract: A method of printing a three-dimensional (3D) object and a support construction for the 3D object includes depositing a model material, layer-by-layer, on a fabrication platform, to print a first portion of the 3D object, and depositing a support material, layer-by-layer on the fabrication platform, to print the support construction, wherein, in a predetermined number of the deposited layers, the model material and the support material are deposited such that a gap is formed between a surface of the first portion of the 3D object and a surface of the support construction.

Abstract: Method of additive manufacturing of a three-dimensional object employing building material formulations that provide, upon exposure to a curing condition, liquid or liquid-like material, and three-dimensional objects obtainable thereby are provided. The methods are usable for fabricating objects featuring one or more hollow structures.