A system for detecting three-dimensional (3D) part drag includes an infrared image capture device to capture a plurality of thermal images of a 3D part build region of a 3D printing device on which a part is built, and an image analysis module to detect drag of the part based on a difference image produced by subtracting a first thermal image from a second thermal image.

A system for detecting three-dimensional (3D) part drag includes an infrared image capture device to capture a plurality of thermal images of a 3D part build region of a 3D printing device on which a part is built, and an image analysis module to detect drag of the part based on a difference image produced by subtracting a first thermal image from a second thermal image.

A method of additively manufacturing an object includes steps of: (1) successively forming a plurality of powder layers by depositing powder; (2) selectively controlling a composition of the powder that forms each one of the plurality of powder layers; and (3) successively forming a plurality of object layers of the object by joining the powder of a portion of each one of the plurality of powder layers before forming each successive one of the plurality of powder layers.

A method of additively manufacturing an object includes steps of: (1) successively forming a plurality of powder layers by depositing powder; (2) selectively controlling a composition of the powder that forms each one of the plurality of powder layers; and (3) successively forming a plurality of object layers of the object by joining the powder of a portion of each one of the plurality of powder layers before forming each successive one of the plurality of powder layers.

A powder spreading apparatus includes a hopper having a first end, a second end opposite from the first end, a front wall, a rear wall opposite from the front wall, and a floor. The front wall, the rear wall, the first end, the second end, and the floor define an interior. An impeller is disposed within the interior of the hopper. The impeller includes a plurality of circumferentially spaced flutes and is configured to rotate about an impeller axis that extends from the first end of the hopper to the second end of the hopper to deposit powder onto a print area. A spreader rod is coupled to the hopper and extends along a spreader rod axis parallel to the impeller axis. The spreader rod is configured to rotate about the spreader rod axis to smooth the powder as it is deposited onto the print area.

A powder spreading apparatus includes a hopper having a first end, a second end opposite from the first end, a front wall, a rear wall opposite from the front wall, and a floor. The front wall, the rear wall, the first end, the second end, and the floor define an interior. An impeller is disposed within the interior of the hopper. The impeller includes a plurality of circumferentially spaced flutes and is configured to rotate about an impeller axis that extends from the first end of the hopper to the second end of the hopper to deposit powder onto a print area. A spreader rod is coupled to the hopper and extends along a spreader rod axis parallel to the impeller axis. The spreader rod is configured to rotate about the spreader rod axis to smooth the powder as it is deposited onto the print area.

A three-dimensional fabrication apparatus includes a flattening member and a rotation drive unit. The flattening member moves on layers of a fabrication material to flatten an upper surface of the layers of the fabrication material. The rotation drive unit rotates the flattening member and determines a circumferential position of the flattening member.

An apparatus (100) for additive manufacturing of a part of an article from a first material comprising particles having a first composition is provided. The apparatus (100) comprises a layer providing means (110) for providing a first support layer from a second material comprising particles having a second composition, wherein the first composition and the second composition are different. The apparatus (100) comprises a concavity defining means (120) for defining a first concavity in an exposed surface of the first support layer. The apparatus (100) comprises a depositing means (130) for depositing a part of the first material in the first concavity defined in the first support layer. The apparatus (100) comprises a levelling means (140) for selectively levelling the deposited first material in the first concavity. The apparatus (100) comprises a first fusing means (150) for fusing some of the particles of the levelled first material in the first concavity by at least partially melting said particles, thereby forming a first part of the layer of the article. In this way, the second material may be thus used to provide a support structure during additive manufacturing of the part of the article.

An apparatus (100) for additive manufacturing of a part of an article from a first material comprising particles having a first composition is provided. The apparatus (100) comprises a layer providing means (110) for providing a first support layer from a second material comprising particles having a second composition, wherein the first composition and the second composition are different. The apparatus (100) comprises a concavity defining means (120) for defining a first concavity in an exposed surface of the first support layer. The apparatus (100) comprises a depositing means (130) for depositing a part of the first material in the first concavity defined in the first support layer. The apparatus (100) comprises a levelling means (140) for selectively levelling the deposited first material in the first concavity. The apparatus (100) comprises a first fusing means (150) for fusing some of the particles of the levelled first material in the first concavity by at least partially melting said particles, thereby forming a first part of the layer of the article. In this way, the second material may be thus used to provide a support structure during additive manufacturing of the part of the article.

This method describes techniques to create 3D parts by dispensing a liquid polymer or slurry in evenly delivered layers, which are exposed to light from a visual display screen before the print platform upon which it is being built is moved one-layer thickness away and the process is repeated. The process of dispensing the photosensitive material is via a pumped system through a metering device that discharges and levels the material. Multiple dispensing devices can be arranged in sequence to deliver different materials, either multiple photosensitive dispensing heads or alternative mechanisms such as robocasting, fused deposition modelling or inkjet in addition to a photosensitive deposition head.