Abstract: Substantially equal amounts of thermal energy may be provided over a build area of an additive fabrication device using as few as one heat source by selectively attenuating thermal energy emitted by the heat source. The thermal energy may be selectively attenuated by a structure that blocks portions of the thermal energy from being directly incident upon the build area such that the heat is normalized over the build area. The heat distribution over the build area may, in some embodiments, approximate the heat distribution produced by a flat field heating element, yet may be produced at comparatively lower cost and with less complex engineering.

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, a method of additive fabrication wherein a plurality of layers of material are formed on a build platform 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, rotating the container relative to the build platform and moving the build platform relative to the container, thereby creating an effective fulcrum about an axis, wherein the rotating of the container and moving of the build platform causes the layer of material to separate from the container. According to some embodiments, the container may be configured to rotate about a fixed axis. According to some embodiments, moving the build platform may comprise moving the build platform toward the container.

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

Abstract: Techniques for measuring a position of a build platform in an additive fabrication device are provided. Such techniques may include detecting the onset and/or dissipation of force applied to a build platform as it moves from being in contact with, to being out of contact with, a container. In some embodiments, the techniques described herein may be applied in a stereolithographic additive fabrication device. According to some embodiments, measurement of forces applied to a build platform may be used to provide for reliable and consistent measurements of the height of the build platform relative to a container by measuring such forces at various positions of the build platform and analyzing the pattern of the forces with distance from the container.

Abstract: Techniques of optically sensing fiducial targets, such as calibration patterns, within an additive fabrication device are provided. In some embodiments, fiducial targets may be disposed on a structure configured to contact source material of the additive fabrication device, the source material being a material from which the device is configured to fabricate solid objects. Indirect sensing means may be employed such that light emitted from a light source of the additive fabrication device scatters from the surface of a fiducial target. At least some of this scattered light can be measured by a sensor and used to determine a position of the fiducial target. In some embodiments, the fiducial target may be configured to move relative to the light source and/or sensor to provide additional information on the target's position via the light scattered from its surface.

Abstract: According to some aspects, an additive fabrication device and a build platform suitable for use within an additive fabrication device are provided. The build platform may include a build surface on which material may be formed by the additive fabrication device when the build platform is installed within the additive fabrication device. According to some embodiments, the build platform may include a flexible build layer and at least one removal mechanism configured to be actuated to apply a force to the flexible build layer. Such actuation may cause the flexible build layer to deform, thereby enabling separation of material adhered to the build surface from the build platform. According to some embodiments, the build platform may comprise a restorative mechanism that acts to return the flexible build layer to a flat state so that subsequent additive fabrication may form material on a flat build surface.

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

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: Techniques for improved efficiency of sintering in additive fabrication are described. According to some aspects, mechanisms for depositing and leveling source material are combined with a mechanism for heating the material. In some embodiments, one or more heating elements may be arranged to lead and/or follow a material deposition mechanism such that heat may be applied to the build region in concert with deposition of material. As a result of this technique, the heating and depositing steps may be performed closer together in time and/or heat may be applied more directly to the material than in conventional systems. As a result, greater control over material temperature may be achieved, thereby avoiding excess temperature exposure and subsequent undesirable changes to the material.

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 embodiments, a method of optimizing an additive fabrication process for an object is provided, the method comprising obtaining a representation of an intermediate form of the object, the intermediate form being an expected shape of the object when partially fabricated by the additive fabrication process, simulating one or more forces expected to be applied to the intermediate form of the object during the additive fabrication process, evaluating one or more results of the simulating step against one or more criteria, and adapting the additive fabrication process based at least in part on a result of the evaluating.

Abstract: According to some aspects, a method of additive fabrication wherein a plurality of layers of material are formed on a build platform is provided. The method comprises forming a raft structure in contact with the build platform, the raft structure formed from one or more layers of material and comprising at least one removal pocket adjacent to the build platform and forming additional material in contact with the raft structure. According to some aspects, an additive fabrication apparatus configured to form a plurality of layers of material on a build platform is provided. The apparatus comprises the build platform, and at least one controller configured to form a raft structure in contact with the build platform, the raft structure formed from one or more layers of material and comprising at least one removal pocket adjacent to the build platform, and form additional material in contact with the raft structure.

Abstract: According to some aspects, an additive fabrication device is provided. The additive fabrication device may be configured to form layers of material on a build platform, each layer of material being formed so as to contact a container in addition to the build platform and/or a previously formed layer of material, and may comprise a build platform, a container, and a plurality of mechanical linkages each independently coupled to the container and configured to move the container relative to the build platform.

Abstract: According to some aspects, an additive fabrication device is provided configured to form layers of material on a build platform, each layer of material being formed so as to contact a container in addition to the build platform and/or a previously formed layer of material. The additive fabrication device may comprise a container and a wiper, wherein the wiper comprises a wiper arm and a wiper blade coupled to said wiper arm using a pivoting coupling.

Abstract: Techniques for designing and fabricating thermal supports via additive fabrication are described. In some additive fabrication techniques, sufficiently high temperature differentials may contribute to any of a diverse array of part defects and failure modes. Additional volumes, referred to as thermal supports, may be fabricated along with a desired object such that the thermal supports adjusted, in a desired manner, temperatures that would otherwise be experience within the fabrication material during fabrication. For instance, the presence of a thermal support structure may serve to reduce changes in temperature experienced by the material between one or more adjacent layers during fabrication. According to some embodiments, thermal supports may be generated to be fabricated with a part so as to not be in contact with the part. Such a thermal support may reduce a temperature differential without affecting the finish of the fabricated object.

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, a method is provided of casting an object from a mold, the method comprising obtaining a mold comprising a hollow shell of rigid material, the material comprising a thermoset polymer having a plurality of pores formed therein, providing a metal and/or ceramic slurry into an interior of the mold, exposing at least part of the mold to a low pressure environment so that a net flow of gas is produced from the interior of the mold into the low pressure environment. According to some aspects, a method of forming a porous mold is provided. According to some aspects, a photocurable liquid composition is provided, comprising a liquid photopolymer resin, particles of a solid material, in an amount between 30% and 60% by volume of the composition, and a water-soluble liquid.

Abstract: According to some aspects, a method is provided of casting an object from a mold, the method comprising obtaining a mold comprising a hollow shell of rigid material, the material comprising a thermoset polymer having a plurality of pores formed therein, providing a metal and/or ceramic slurry into an interior of the mold, exposing at least part of the mold to a low pressure environment so that a net flow of gas is produced from the interior of the mold into the low pressure environment. According to some aspects, a method of forming a porous mold is provided. According to some aspects, a photocurable liquid composition is provided, comprising a liquid photopolymer resin, particles of a solid material, in an amount between 30% and 60% by volume of the composition, and a water-soluble liquid.