Abstract: A method for dynamically controlling layer thickness during an additive manufacturing process of building a block including an object with layers of powder material, detecting a height of the block after each layer is compacted, determining a delta between the detected height and a height in a computer model defining slices of the block and compensating for the determined delta in subsequent cycles. A cycle in the additive manufacturing process includes selectively printing a layer pattern, spreading a powder layer over the layer pattern with a spreader and compacting the powder layer with the layer pattern.

Abstract: Methods of fabricating three-dimensional objects featuring properties of a soft bodily tissue and three-dimensional objects featuring properties of a soft bodily tissue or of an organ comprising same are provided.

Abstract: A tubular structure fabricated by additive manufacturing from non-biological building material formulations, and featuring an elongated core, a shell encapsulating the core and an intermediate shell between the core and the shell. Each of the core, the shell and the intermediate shell is made of a different material or a different combination of materials. Both the core and the intermediate shell are sacrificial. Additive manufacturing of the tubular structure is usable for fabricating an object featuring properties of a blood vessel.

Abstract: Novel support material formulations, characterized as providing a cured support material which is readily removable by contacting with water, are disclosed. The formulations comprise a curable water-soluble mono-functional monomer, a water-miscible polymer and a silicone polyether. Methods of fabricating a three-dimensional object, and a three-dimensional object fabricated thereby are also disclosed.

Abstract: Apparatus for producing a three-dimensional model by sequentially forming layers of photopolymer material one on top of the other responsive to data defining the three-dimensional model is disclosed. The apparatus includes at least one printing head configured to dispense the photopolymer material, an array of LEDs controllable to provide radiation to polymerize the photopolymer material and a controller. The controller is configured to control the at least one printing head to dispense the photopolymer material to sequentially form the layers of material. The controller is also configured to turn on the array of LEDs to provide the radiation to cure the photopolymer material when situated above the model and to turn off the array of LEDs when not situated above the model.

Abstract: A direct inkjet printing system for fabricating a part by an additive manufacturing process includes an ink delivery system operative to circulate the ink, a printhead associated with the ink delivery system, the printhead operative to dispense ink from the ink delivery system through a plurality of nozzles and based on a defined pattern, a building table for receiving the dispensed ink one layer at a time based on the defined pattern, wherein the part is formed from a plurality of layers of the ink dispensed from the printhead and a drying station operative to perform a drying process on layers of the ink dispensed from the printhead on a per layer basis.

Abstract: A printing head for a printing system is disclosed. The printing head comprises a plurality of compartments, each having an outlet port for depositing liquid and an inlet port separately connectable to a separate liquid container. At least two compartments are in controllable fluid communication with each other, and the printing head comprises an arrangement of sensors configured for generating signals indicative of (i) a filling state of each compartment, and (ii) a fluid communication state between the at least two compartments.

Abstract: A pressure controlling system for an inkjet printer includes a pressure chamber, a pump fluidically connected to the chamber and adapted for increasing or decreasing the pressure within the pressure chamber, a controllable three port two way valve, and a sensing unit including one or more pressure sensors. The pressure sensing unit is in fluidic communication with the pressure chamber for sensing the pressure therein. The valve has a first port controllably fluidically connectable to the pressure chamber, a second port controllably fluidically connectable to an inkjet print head, and a third port controllably fluidically connectable with atmospheric air. The sensing unit is adapted for sending signals representative of the pressure within the pressure chamber to at least one processor/controller. The pump and the valve are controlled by receiving control signals from the processor/controller(s). There are provided a method for operating the system and a printer including the system.

Abstract: A method of rendering data for addressable dispensing of material over a working surface, comprises: receiving input image data arranged grid-wise over a plurality of picture-elements; generating an initial map describing a distance field and having a plurality of map-elements each storing distance information corresponding to one picture-element; for each picture-element of at least a portion of the picture-elements: linearly scanning the map independently along a first axis and along a second axis, and updating a respective map-element based on values of map-elements visited during the scan. The distance field can include distances defined perpendicularly to the working surface.

Abstract: Methods for fabricating three-dimensional objects by 3D-inkjet printing technology are provided. The methods utilize a combination of curable materials that polymerize via ring-opening metathesis polymerization (ROMP) and curable materials that polymerize via free-radical polymerization (FRP) for fabricating the object. Systems suitable for performing these methods, kits containing modeling material formulations usable in the methods and objects obtained thereby are also provided.

Abstract: Formulations usable as support material in additive manufacturing such as 3D inkjet printing and which feature a viscosity of no more than 50 cPs at 35° C., are provided. The formulations are composed of at least one hydrophilic curable material which provides, when hardened, a material that is dissolvable or swellable in an aqueous solution; and at least one non-curable material that is capable of being swelled by said hardened material formed of said at least one curable material. Additive manufacturing processes utilizing these formulations and objects obtained thereby are also provided.

Abstract: Described herein is a method of additive manufacturing of a three-dimensional object having an agent which promotes electroless metal deposition dispersed therein in a configured pattern. The method utilizes modeling material formulation(s) which comprise and/or are capable of generating such an agent. Further described is a method of manufacturing a three-dimensional object having an electrically-conductive material dispersed in a configured pattern. The method utilizes an object having an agent which promotes electroless metal deposition dispersed therein in a configured pattern and manufactured by the aforementioned method, and proceeds by contacting the three-dimensional object with an electroless deposition solution so as to effect the electroless deposition onto the configured pattern. Further described are kits for use in additive manufacturing as described herein; as well as three-dimensional objects which may be manufactured as described herein.

Abstract: A method of additive manufacturing of a three-dimensional object includes sequentially dispensing and solidifying a plurality of layers. The plurality of layers may be formed with a plurality of different colored model materials, a flexible material arranged in a configured pattern to form a sacrificial structure at least partially encompassing the object, and a soft material. The soft material is arranged in a configured pattern to provide separation between the model material and the sacrificial structure. The plurality of different colored model materials is arranged in a configured pattern corresponding to the shape and color definition of the object.

Abstract: A method of additive manufacturing a three-dimensional object by layerwise deposition of a building material with an inkjet printing system comprising a print head and a building tray, comprises calculating a weighting value for each nozzle, then for each layer obtaining a 2-D map of the layer, comprising active pixels at building material dispensing positions; obtaining a Data Correction Filter (DCF) including a height map of the previous layer, comparing the data of the 2D map to the data of the DCF at each position and determining if the nozzle at that position should dispense, then printing the layer, updating the weighting values and adjusting the position of the print head vis a vis the printing tray. The above is repeated until the three-dimensional object is printed.

Abstract: A scanning 3-D printing system comprises a printing platform movable in a printing direction and in an indexing direction, the printing platform comprising a printing head configured for dispensing building material while the printing platform is moving in a printing direction one pass at a time, and layer by layer, a roller configured for leveling the dispensed building material one pass at a time, wherein the roller is rotatably mounted on a roller axle, and wherein the roller axle extends over all passes of the printing system and is stationary in the indexing direction, a scraper configured for scraping excess building material off the roller, and a trough configured for collecting the building material scraped off the roller.

Abstract: An apparatus includes a roller that skims a layer of material deposited by an additive manufacturing (AM) system, a blade that scrapes material accumulated on the roller, a bath that collects material scraped by the blade, and an auger that transports material collected in the bath to a portion of the bath that extends beyond a length of the roller.

Abstract: Novel support material formulations, characterized as providing a cured support material which is readily removable by contacting with water, are disclosed. The formulations comprise a curable water-soluble mono-functional monomer, a water-miscible polymer and a silicone polyether. Methods of fabricating a three-dimensional object, and a three-dimensional object fabricated thereby are also disclosed.

Abstract: A method of three-dimensional fabrication of an object is disclosed. The method comprises: forming a plurality of layers in a configured pattern corresponding to the shape of the three-dimensional object, at least one layer of the plurality of layers being formed at a predetermined and different thickness selected so as to compensate for post-formation shrinkage of the layer along a vertical direction. In various exemplary embodiments of the invention spread of building material of one or more layers is diluted at least locally such as to maintain a predetermined thickness and a predetermined planar resolution for the layer.

Abstract: A three-dimensional printing system to print three-dimensional objects and a method of printed are disclosed. The system includes a printing apparatus to print three-dimensional objects and a controller to receive data from a material supply source and to control said printing apparatus.

Abstract: A method of producing an object by sequentially printing layers of construction material one on top of the other, the method comprising: providing the construction material at a first lower temperature; flowing the construction material through a heated flow path in a flow structure to heat the construction material and delivering the heated construction material to a heated reservoir in a printing head; and dispensing the heated construction material from the reservoir to build the object layer by layer.