Abstract: A method for producing a three-dimensional object on an additive fabrication device includes placing a first composite material patch on a bottom of a vessel of the additive fabrication device. The method also includes moving a build plate of the additive fabrication device whereby at least one of the build platform or a layer of at least partially cured resin on the build plate touches the first composite material patch. The method further includes irradiating resin contained inside the vessel with an energy source to at least partially cure a layer of resin integrated with the first composite material patch.

Abstract: A post-processing device configured to be coupled to a three-dimensional printer. The post-processing device includes a head assembly that includes a release device and a collection device. A rail extends in a first direction, and the head assembly is configured to travel along the rail. The device also includes a pedestal assembly configured to be coupled to a base of the three-dimensional printer, and an opening device for opening a cover of the three-dimensional printer. At a parts collection location on the rail, the release device of the head assembly is configured to engage with a build platform of the three-dimensional printer to release printed parts on the build platform, and the collection device of the head assembly is below the build platform and is configured to collect the released printed parts.

Abstract: Techniques are described for consistently moving powder from a hopper into a trough for subsequent delivery into a build area of an additive fabrication system. A powder delivery apparatus may comprise a hopper, a trough, and a doser. The doser may be configured to rotate about an axis and may include a recess that, when the doser is rotated about the axis, travels into and out of the hopper and into and out of the trough. As a result, when powder is present in the hopper, the recess may carry powder from the hopper to the trough when the doser rotates. The trough and doser may be configured so that when the trough contains the desired amount of powder for recoating, the doser does not transfer additional material from the hopper into the trough. As a result, the amount of powder in the trough may be self-regulating.

Abstract: According to some aspects, techniques are provided for identifying contamination in additive fabrication devices by measuring light interacting with the contamination using one or more light sensors. Contamination located between a light source and a target of a light source can affect the uniformity and intensity of the light source when incident upon the target. For instance, in an inverse stereolithography device, contamination located between a light source and a liquid photopolymer resin that is to be cured can affect the quality of the fabricated object when the light is scattered or blocked by the contamination. Identifying the presence of contamination between the light source and the liquid photopolymer resin and alerting the user prior to initiating a fabrication process may increase the quality of the resulting fabricated object and improve the user experience by saving time and photocurable liquid.

Abstract: A method includes curing a photopolymer resin disposed between a first build surface and a flexible film layer to form a print layer of a printed part. Here, the print layer of the printed part defines a second build surface attached to the flexible film layer. The method also includes translating a peeling mechanism between the second build surface and the flexible film layer to detach the flexible film layer from the second build surface.

Abstract: A curing system for an additive fabrication system includes a light source, a liquid crystal cell, and a first polarizer. The light source is configured to emit light at a wavelength suitable for curing a material. The liquid crystal cell is configured to receive the light from the light source. The first polarizer comprises a polyvinyl alcohol (PVA) matrix and organic dyes impregnated into the PVA matrix.

Abstract: A curing system includes a basin configured to receive a photopolymer resin, an ultraviolet light source, and a translating device. The ultraviolet light source is configured to selectively emit ultraviolet light. The ultraviolet light defines a pixelated array that illuminates at least a portion of the photopolymer resin. The pixelated array includes a first array axis and a second array axis oriented perpendicular to the first array axis. The translating device is configured to translate the pixelated array along a translation axis at an oblique angle relative to the first array axis.

Abstract: The present disclosure relates generally to curable resins, in particular latent cure resins, and related methods for use in an additive fabrication (e.g., 3-dimensional printing) device.

Abstract: Techniques for force sensing in additive fabrication are provided. According to some aspects, an additive fabrication device may include a force sensor configured to measure a force applied to a build platform during fabrication. A length of time taken for a layer of material to separate from a surface other than the build platform to which it is adhered may be determined based on measurements from the force sensor. Subsequent additive fabrication operations, such as subsequent motion of the build platform, may be adapted based on the determined length of time.

Abstract: According to some aspects, a method of additive fabrication wherein a plurality of layers of material are formed is provided. The method may comprise forming a layer of material in contact with a container, and subsequent to the forming of the layer of material, actively bending the container around at least one fixed point such that the layer of material separates from the container. According to some aspects, an additive fabrication apparatus configured to form a plurality of layers of material is provided. The apparatus may comprise a container, a build platform, one or more force generators, and at least one controller configured to, subsequent to formation of a layer of material in contact with the container, actively bend the container around at least one fixed point via the one or more force generators, such that the layer of material separates from the container.

Abstract: According to some aspects, calibration techniques are provided that allow an optics module of an additive fabrication device to be installed and operated in a stereolithography device by a user. In particular, the calibration techniques enable the optics module to be calibrated in a way that only depends on the characteristics of the optics module, and not upon any other components of the stereolithography device. As a result, the techniques enable a user of a stereolithography device to remove one optics module and replace it with another, without it being necessary to repair or replace the whole device. In some cases, the calibration techniques may include directing light onto one or more fiducial targets within the stereolithography device and measuring light scattered from said targets.

Abstract: Techniques for illuminating a photocurable material within a build area of an additive fabrication device are described. According to some aspects, a light source is provided that can be moved alongside a build area, allowing light to be directed to any desired position within the build area by moving the light source. This configuration may also allow the distance from the light source to the build area to be substantially the same for each position across the build area by moving the light source whilst maintaining a fixed distance from the light source to the build volume. The described approach may allow for fabrication of larger parts in an additive fabrication device by expanding or eliminating the practical upper limit on the area of the build volume that can be imposed by use of a laser light source in such a device.

Abstract: An improved additive fabrication device and a build platform are provided. The additive fabrication device is configured to form layers of material on a build surface. The additive fabrication device comprising: a build platform comprising: a rigid structure; an actuation structure attached to the rigid structure, wherein the actuation structure comprises one or more sheet handles and a flexible sheet, and wherein a first surface of the flexible sheet forms a build surface on which the additive fabrication device is configured to form layers of materials; and the one or more sheet handles are configured to be actuated to apply a force to the flexible sheet while at least a part of the actuation structure remains attached to the rigid structure, to deform at least a part of the flexible sheet away from the rigid structure.

Abstract: Washing apparatus and methods used to process additively fabricated (e.g., 3D printed) parts are described herein. The apparatus and methods may be used to wash uncured liquid resin from the parts.

Abstract: According to some aspects, a method is provided of removing debris from a liquid photopolymer in an additive fabrication device. According to some embodiments, a mesh of solid material may be formed in an additive fabrication device from a liquid photopolymer, and particles of debris present in the liquid photopolymer may adhere to the mesh. The debris may thereby be removed from the liquid photopolymer by removing the mesh from the additive fabrication device. The mesh may then be discarded.

Abstract: According to some aspects, a method of additive fabrication is provided wherein a plurality of layers are formed on a build platform, each layer contacting a container in addition to the build platform and/or a previously formed layer, the method comprising calculating, using at least one processor, one or more forces to be applied to a first layer of the plurality of layers subsequent to the first layer being formed, said calculating being based at least in part on a determined area of at least one portion of the first layer that overhangs a second layer of the plurality of layers, forming the first layer, the first layer being in contact with the container and in contact with a previously formed layer of the plurality of layers, and separating the first layer from the container by applying the calculated one or more forces to the first layer.

Abstract: According to some aspects, an additive fabrication apparatus is provided configured to form layers of material on a build platform, each layer of material being formed so as to contact a supporting liquid or a film disposed within a container, in addition to the build platform, a liquid photopolymer, and/or a previously formed layer of a material. The additive fabrication apparatus may comprise a container and a leveling element, wherein the leveling element is configured to move across a liquid-liquid interface to promote or create a flat interface between the two liquids. According to some aspects, the additive fabrication comprises a film disposed between two liquids, wherein the film maintains or provides a flat surface at the interface of the two liquids.