Abstract: Examples of temperature measurement calibration in an additive manufacturing system are described. In one case, a method of calibrating a non-contact temperature measurement device involves applying energy from a radiation source of the additive manufacturing system to heat a reference element. The reference element is thermally coupled to a temperature sensor. A temperature reading from the temperature sensor is compared with data from the non-contact temperature measurement device to calibrate the device.

Abstract: According to one example, there is provided a method of additive manufacturing that comprises obtaining data relating to a 3D object to be manufactured, forming a layer of build material on a build platform, applying a cooling agent in a pattern surrounding a portion of build material to be solidified, and applying energy only to the build material on which cooling agent is applied and to the surrounded portion of build material such that the surrounded portion of build material heats up sufficiently to coalesces, and such that build material on which cooling agent is applied is cooled by the cooling agent and is prevented from heating up sufficiently to coalesce.

Abstract: In an example, a method includes forming a layer of build material and selectively applying fusing agent on to the layer based on a predetermined pattern. Energy may be applied to the layer of build material, and at least one temperature of the layer may be measured. A temperature distribution over the layer of build material may be determined, the temperature distribution indicating, for each of a plurality of locations on the layer of build material, whether fusing agent is present at that location. At least one characteristic derived from the temperature distribution may be compared to a predetermined characteristic. When the compared characteristics differ, an operational characteristic of an additive manufacturing apparatus may be adjusted.

Abstract: An apparatus (100) for generating three dimensional objects comprises a first scanning carriage (102). The first scanning carriage comprises a first energy source (104) to pre-heat an area of a build surface as the first scanning carriage (102) moves over the build surface.

Abstract: A reflector assembly for an additive manufacturing apparatus comprises a first reflector comprising a first reflector section having a first reflecting surface and a second reflector comprising a second reflector section having a second reflecting surface. The first reflector section is for reflecting radiation from a first radiating element located, in use, proximate to the first reflecting surface, and the second reflector section is for reflecting radiation from a second radiating element located, in use, proximate to the second reflecting surface. The first reflector section and the second reflector section are each formed of a ceramic material.

Abstract: According to examples, a build module may include a housing, a build material chamber, and a build chamber. The build material chamber may be positioned beneath the build chamber in the housing and may include a moveable support member, in which a build material distributor is to supply successive layers of build material onto the moveable support member from the build material chamber. The build module may be removably insertable into a build receiver of an additive manufacturing system to allow the additive manufacturing system to solidify a portion of the successive layers received onto the moveable support member during the solidification process of the build material. The moveable support member may separate the build material chamber from the build chamber to block build material from the above the build material chamber from being received into the build material chamber during a solidification process of the build material.

Abstract: An example of an additive manufacturing system is disclosed. The example disclosed herein comprises a build material distributor, a preheating source, and a controller. The build material distributor is to form build material layers from an intended build material having a color. The preheating source is to emit energy at a wavelength related to the intended build material color so that at least a 40% of the energy is absorbed by the build material. The controller is to receive printing instructions to print a 3D object, wherein the printing instructions define an area to be fused in a build material layer. The controller is also to instruct the build material distributor to form the build material layer. The controller is further to control the preheating source to emit energy to preheat a zone comprising the area to be fused.

Abstract: An example of an additive manufacturing system is disclosed. The example disclosed herein comprises a build material distributor, a color module, a preheating source, and a controller. The build material distributor is to form build material layers. The color module is to eject a composition that dyes a build material layer with a color. The preheating source is to emit energy at a wavelength related to the dyed build material color so that at least a 40% of the energy is absorbed by the dyed build material. The controller is to receive printing instructions to print a 3D object, wherein the printing instructions define an area to be fused in a build material layer. The controller is also to instruct the build material distributor to form the build material layer. The controller is to instruct the color module to eject the composition to color the build material from the build material layer in a zone comprising the area to be fused.

Abstract: A build module is provided. The build module may include a housing and a build material chamber in the housing to hold build material. The build module may include a build chamber in the housing. The build material chamber may be beneath the build chamber or next to the build chamber. The build chamber may include a moveable support member to receive successive layers of the build material from a build material distributor. The build module may be removably insertable into a build receiver of an additive manufacturing system to allow the additive manufacturing system to solidify a portion the successive layers to be received onto the movable support member.

Abstract: In an example, an air filtration apparatus includes a cyclonic particle separation chamber having a first inlet to draw air from a first region, second inlet to draw air from a second region, and an exhaust port. The air filtration apparatus may further include a pressure sensor to sense a pressure of the first region, and a cyclonic air flow controller. The cyclonic air flow controller may control an air inflow received via the second inlet in response to an output from the pressure sensor to maintain a total air flow rate via the exhaust port.

Abstract: A method and apparatus is described in which a signal indicative of an operation of a energy source of a 3D printer during a second predetermined time period commencing with the end of a first predetermined time period is obtained, the first predetermined time period commencing with an activation of the energy source, wherein the energy source is active throughout the first and second time periods; the obtained signal is compared with a reference signal; and it is determined, based on the comparison, whether the energy source is operating according to predetermined characteristics.

Abstract: An example apparatus to produce a three-dimensional object comprises a controller, a build area configured to receive a layer of particulate material, a printhead, and an ultraviolet light emitting diode energy source. The controller is to cause the printhead to deposit a liquid which absorbs ultraviolet radiation onto the layer of particulate material. The controller is further to cause the ultraviolet light emitting diode energy source to irradiate the liquid, after the liquid has been deposited onto the layer of particulate material, thereby to heat the liquid and cause a portion of the particulate material to solidify.

Abstract: Certain examples described herein relate to manufacturing a three-dimensional object. In some cases, a layer of build material is formed. An array of heat sources is controlled to selectively heat a sub-region of the layer of build material. Each heat source is individually addressable in the array to emit radiation independently of any other heat source in the array. Each heat source comprises a light-emitting diode, LED. In some cases, a fusing agent is deposited onto at least a part of the heated sub-region. Energy is applied at least to the deposited fusing agent to enable fusing of build material to fabricate a layer of the three dimensional object.

Abstract: According to one example, there is provided a method of controlling a three-dimensional printing system, comprising obtaining data relating to a three-dimensional object to be generated, controlling a set of process modules to move around a path in a single direction over a build chamber to selectively perform a respective process action on the build platform to generate a three-dimensional object therein.

Abstract: In an example, a filtration apparatus includes a cyclonic particle separation chamber having an inner surface and a liquid source. The liquid source may be to supply liquid to provide a flow of liquid on the inner surface.

Abstract: According to one example, there is provided a system for generating a three-dimensional object. The system comprises a carriage to move bi-directionally along a first axis relative to a support platform. The carriage is to receive, or have installed thereon, a plurality of modules each to perform an operation from a set of operations to generate a layer of a three-dimensional object. The system further comprises a controller to cause relative movement between the carriage and the support platform along the first axis, and to control, during the relative movement, operation of the modules to perform the set of operations in a predefined order.

Abstract: According to one example, there is provided apparatus for generating a three-dimensional object. The apparatus comprises a build material distributor movable bi-directionally in a first axis to deposit successive layers of a build material on a support, and an agent distributor movable bi-directionally in a second axis different to the first axis to deliver an agent onto selected portions of successive layers of build material.

Abstract: A method of forming a three-dimensional object includes detecting, with a thermographic camera, a temperature of a control point within at least one zone of the build material bed, and adjusting a power level supplied to at least one of the lamps of the array of lamps if the detected temperature of the control point of the at least one zone of the build material bed is not equal to a set temperature.

Abstract: According to one example, there is provided apparatus for generating a three-dimensional object. The apparatus comprises a build material distributor movable bi-directionally in a first axis to deposit successive layers of a build material on a support, and an agent distributor movable bi-directionally in a second axis different to the first axis to deliver an agent onto selected portions of successive layers of build material.

Abstract: An electromagnetic filtering system comprising an electromagnetic radiation source, a filter chamber to filter the radiation and a filter chamber control system to selectively modify the contents of the filter chamber in order to modify the wavelengths of the radiation that pass through the filter chamber. There is also provided a method of controlling an electromagnetic filtering system that comprises a controllable filter chamber capable of being controlled so as to selectively be filled with a filter material, the method comprising —determining filtering characteristics to be provided by the filtering system, —determining whether the filter chamber should be filled with the filter material, and —controlling the filter chamber to be filled as determined.