Abstract: According to examples, an apparatus may include a processor and a memory on which are stored machine-readable instructions that when executed by the processor, cause the processor to determine physical characteristics of a build layer of build material particles. The instructions may also cause the processor to determine an adjustment to forming data based on the determined physical characteristics, the forming data to be used informing a subsequent build layer. The instructions may further cause the processor to apply the determined adjustment to the forming data for use in forming the subsequent build layer, in which portions of a three-dimensional (3D) object are to be formed in the build layer and the subsequent build layer.

Abstract: Printers are disclosed. An example printer includes a build controller to access metrics of a layer on a work area and to select a dosing profile from a plurality of dosing profiles to fuse the layer based on the metrics.

Abstract: In some examples, a system receives measurement data obtained based on a non-destructive imaging of an identifiable structure within a three-dimensional (3D) object formed using an additive manufacturing machine, the identifiable structure formed based on control of a characteristic of a build material of a first internal object portion relative to a characteristic of the build material in a second internal object portion, the first and second internal object portions being within the 3D object. The system determines, based on the measurement data, a deviation of a physical property of the identifiable structure from a target physical property, and outputs information indicating the deviation.

Abstract: A 3D printer is disclosed herein. The 3D printer comprises a build material distributor to generate layers of a build material in a spreading direction along a spreading axis; a resonator mounted on the build material distributor to vibrate the build material distributor along the spreading axis at a frequency; and a controller. The controller is to control the resonator to vibrate the build material distributor at the frequency while controlling the build material distributor to spread a volume of build material over a platform to generate a layer of build material.

Abstract: According to examples, a system may include a recoater and a controller. The controller may identify a structure of a surface of a layer of build material formed on a build platform and may determine whether the identified structure of the surface includes a portion that has a property that is outside of a predefined property level. Based on a determination that the portion has a property that is outside of the predefined property level, an adjustment to be applied to an operation of the recoater to achieve an intended structure of the layer and/or an intended structure of a subsequent layer may be determined and the determined adjustment on the operation of the recoater may be applied.

Abstract: A printing device for adapting a printing parameter in relation to the height of a layer of material deposited during an additive manufacturing process is disclosed. The printing device comprises a printing component to deposit a layer of material that is to be solidified so as to form at least a portion of an object, a controller to determine the height of the layer of material at various positions across the layer and to select voxels of a data model of the object, the selected voxels correspond to the height of the layer of material at said various positions, and the controller is further to use the selected voxels as input for calculating a printing parameter.

Abstract: According to examples, an apparatus may include a processor and a memory on which are stored machine-readable instructions that when executed by the processor, cause the processor to determine physical characteristics of a build layer of build material particles. The instructions may also cause the processor to determine an adjustment to forming data based on the determined physical characteristics, the forming data to be used informing a subsequent build layer. The instructions may further cause the processor to apply the determined adjustment to the forming data for use in forming the subsequent build layer, in which portions of a three-dimensional (3D) object are to be formed in the build layer and the subsequent build layer.

Abstract: In an example implementation, a method of determining liquid agent amounts in 3D printing includes measuring density levels of a build material at locations across a build material layer and determining if the measured density levels vary from expected density levels. For locations where measured density levels vary from expected density levels, an adjusted liquid agent dose is determined, and for locations where measured density levels do not vary from expected density levels, an expected liquid agent dose is determined. The adjusted and expected liquid agent doses are deposited onto the layer at locations corresponding with the adjusted and expected liquid agent doses.

Abstract: A printing device for adapting a printing parameter in relation to the height of a layer of material deposited during an additive manufacturing process is disclosed. The printing device comprises a printing component to deposit a layer of material that is to be solidified so as to form at least a portion of an object, a controller to determine the height of the layer of material at various positions across the layer and to select voxels of a data model of the object, the selected voxels correspond to the height of the layer of material at said various positions, and the controller is further to use the selected voxels as input for calculating a printing parameter.

Abstract: According to examples, an apparatus may include a processor and a memory on which is stored machine readable instructions. The processor may execute the instructions to access a first stereoscopic three-dimensional (3D) image of a surface of a layer of build material particles and a second stereoscopic 3D image of the layer surface, the second stereoscopic 3D image being captured at a later time than the first stereoscopic 3D image. The processor may also generate a 3D deformation map of the layer surface from the first stereoscopic 3D image and the second stereoscopic 3D image and may implement an action based on the generated 3D deformation map of the layer surface.

Abstract: According to examples, an apparatus may include a processor and a memory on which are stored machine-readable instructions that when executed by the processor, cause the processor to access a stereoscopic three-dimensional (3D) image of a layer including solidified build material particles. The instructions may also cause the processor to identify an optical property of the solidified build material particles at a location on the layer from the stereoscopic 3D image. The instructions may further cause the processor to determine whether the identified optical property exceeds a predefined threshold and based on a determination that the identified optical property exceeds the predefined threshold, output an indication that the layer includes an optical property that exceeds the predefined threshold.

Abstract: According to examples, an apparatus may include a processor and a memory on which are stored machine readable instructions that when executed by the processor, cause the processor to determine whether a first surface map includes a dropout, the first surface map being generated using a first image parameter on a first image and a second image. The instructions may also cause the processor to, based on a determination that the first surface map includes a dropout, recover information corresponding to the dropout. The instructions may further cause the processor to generate a recovered surface map using the recovered information and store the recovered surface map.

Abstract: An example method includes forming a layer of build material on a build platform of a 3-D printer and correlating X-Y position data and stereoscopic Z-position data for particles of the build material in the layer of build material that are determined to exceed a threshold criteria based on a measure attribute.

Abstract: Example methods, apparatus, systems, and articles of manufacturing for calibrating a stereo vision system are described herein. An example stereo vision calibration system includes an automated calibration target stand to support a calibration target. The example stereo vision calibration system further includes a calibrator to control the automated calibration target stand to move the calibration target to a plurality of positions according to a sequence of positions while the automated calibration target stand is disposed in an additive manufacturing (AM) machine, and control a stereo vision system of the AM machine to obtain images of the calibration target in the plurality of positions.

Abstract: Printers are disclosed. An example printer includes a build controller to access metrics of a layer on a work area and to select a dosing profile from a plurality of dosing profiles to fuse the layer based on the metrics.