Abstract: Apparatus to produce a three-dimensional object and methods of producing a three-dimensional object are described. In some examples, a first fluid comprising a colorant and a second fluid comprising an absorber to absorb electromagnetic radiation are applied on a layer of particulate material. Application of the second fluid to the layer of particulate material is in dependence on an ability of the first fluid to absorb the electromagnetic radiation.

Abstract: In an example, a method includes in an additive manufacturing process, generating a first object and generating an ancillary object on top of the first object to reduce a thermal gradient of the first object during cooling.

Abstract: In an example, object model data representing at least a portion of an object defining an initial object geometry is received, wherein the object is to be generated by an additive manufacturing apparatus by fusing build material using a radiant heater. Based on a non-uniform radiant heating distribution of the additive manufacturing apparatus, a modified object geometry may be determined, wherein a local modification of the object geometry is determined based on a local radiant heating parameter determined from the non-uniform radiant heating distribution.

Abstract: A 3D printer is disclosed herein. The 3D printer comprises a build material distributor to generate layers of a build material having a right limit temperature of the build material crystallization curve higher than a left limit temperature of the build material fusing curve. The 3D printer also comprises an agent distributor to selectively deposit an energy absorbent fusing agent to a layer of build material; an energy source to emit energy at a set of wavelengths comprised in the range of 430 to 1200 nm; and a controller. The controller is to receive print job data of a 3D object to be generated; control the build material distributor to generate a layer of build material; control the agent distributor to selectively deposit the fusing agent based on the print job data; and to control the energy source to emit energy to the layer of build material to cause build material on which the fusing agent was deposited to melt, coalesce and then solidify upon cooling.

Abstract: Examples include apparatuses, processes, and methods for generating three-dimensional objects. An example apparatus comprises build material distributor and a controller. Examples distribute a particular build layer in a build area of the apparatus over a previous build layer. Examples determine a build layer temperature corresponding to the particular build layer. Examples analyze build layer coverage for the particular build layer based at least in part on a build layer temperature of the previous build layer and the build layer temperature of the particular build layer. Examples selectively recoat the particular build layer with additional build material based at least in part on the build layer coverage for the particular build layer.

Abstract: Examples include apparatuses, processes, and methods for generating three-dimensional objects. An example apparatus comprises build material distributor and a controller. Examples distribute a particular build layer in a build area of the apparatus over a previous build layer. Examples determine a build layer temperature corresponding to the particular build layer. Examples analyze build layer coverage for the particular build layer based at least in part on a build layer temperature of the previous build layer and the build layer temperature of the particular build layer. Examples selectively recoat the particular build layer with additional build material based at least in part on the build layer coverage for the particular build layer.

Abstract: There is disclosed additive manufacturing apparatus comprising: a controller to: receive object data relating to an object to be generated; and define print data for additive manufacture of the object by ejection of a print agent on build material in a pattern corresponding to selective fusing of the build material, wherein the print data is defined based on the object data so that the pattern defines a shield feature embedded within the object to inhibit fusing of build material corresponding to the shield feature relative build material corresponding to an adjacent portion of the object; and a print agent distributor to eject a print agent on build material based on the print data.

Abstract: Disclosed are systems, control mechanisms and methods that apply different printer control fluid parameters when forming internal and external features of a three-dimensional object within an additive manufacturing system. The identification of internal and external features may involve analysing an object model, comprising data describing the object to be manufactured, to identify all edges of a three-dimensional object and determining which of the edges are internal edges and which are external edges of the object. A control fluid strategy can be optimised for different object feature types, to improve mechanical properties of the final object and/or reduce usage of detailing agent.

Abstract: Certain examples described herein relate to preparing a base of build material for additive manufacturing. The base is formed from layers of build material that do not form part of an object undergoing additive manufacture. The base is heated by the application of energy, for example using a radiation source. A thermal profile of the base is measured after heating and is used to determine a pattern of application of at least one printing agent to the base. The pattern of application is used to deposit the at least one printing agent upon the base, wherein the presence of the printing agent affects the heating of the base. In this way the pattern of application of printing agent may be used to effect a thermal homogeneity of the base.

Abstract: In an example, a method of controlling an additive manufacturing apparatus to generate a three dimensional object comprises processing successive layers of build material so as to form successive layers of a three dimensional object, wherein the processing of each layer is performed within a predetermined layer processing time by a plurality of components. The method may further include selecting, by at least one processor, from a plurality of ancillary tasks, at least one ancillary task to be performed in relation to at least one component of the plurality of components. The method may further include scheduling, by at least one processor, the at least one ancillary task to be performed in relation to the at least one component within the predetermined layer processing time for a single layer or for multiple layers of the build material.

Abstract: According to an example, a 3D printer may include a delivery device and a controller. The controller may access a morphology of a part to be formed from a plurality of build materials in a layer, determine, based upon the accessed morphology, a first delivery pattern for the delivery device to selectively deliver liquid droplets onto build materials in the layer during a first pass over the layer and a second delivery pattern for the delivery device to selectively deliver liquid droplets onto build materials in the layer during a second pass over the layer to control a property of the part formed of some of the build materials in the layer. The controller may also control the delivery device to selectively deliver liquid droplets onto build materials in the layer according to the determined first and second delivery patterns respectively during the first pass and the second pass.

Abstract: Examples are described that generate control data for production of a three-dimensional object. Build material profile data is accessed for an indicated build material. The build material profile data for a given build material defines one or more parameter values that are dependent on the properties of the given build material and that are configured to generate a three-dimensional object with predefined build properties.

Abstract: Examples of methods for part packing based on agent usage are described herein. In some examples, a method includes or methods include determining an agent usage for each of a plurality of packings. In some examples, the method includes or methods include selecting a packing from the plurality of packings based on the agent usages.

Abstract: Example additive manufacturing apparatus is disclosed comprising a print agent distributor, and a controller to define print data for additive manufacture of a solid part of an object to be manufactured, wherein the print data is to cause a print agent distributor to apply fusing agent to portions of a layer of build material, wherein the print data is to cause a print agent distributor to apply fusing agent to portions of a layer of build material at a concentration based on a distance of each portion of build material from an edge of the object such that the print data causes the print agent distributor to apply fusing agent to portions of a layer of build material having a first range of distances at a first range of concentrations, apply fusing agent to portions of build material having a second range of distances at a second range of concentrations lower than the first range of concentrations, apply fusing agent to portions of build material having a third range of distances at the first range of concent

Abstract: An example method includes acquiring a model of an object to be generated in three-dimensional object generation which is segmented into a plurality of object model sub-volumes, each sub-volume representing a region of the object which is individually addressable in object generation. Object model sub-volumes within a first depth of an object model surface are defined at a first resolution and object model sub-volumes beyond the first depth are defined at a second resolution, and the first resolution is a higher resolution than the second resolution. An object generation model is applied to the object model to determine at least one predicted dimensional deviation of the object in object generation. A geometric adjustment to the segmented object model may be determined to compensate for the predicted dimensional deviation by adding and/or removing at least one object model sub-volume defined at the first resolution.

Abstract: In an example, object model data representing at least a portion of an object defining an initial object geometry is received, wherein the object is to be generated by an additive manufacturing apparatus by fusing build material using a radiant heater. Based on a non-uniform radiant heating distribution of the additive manufacturing apparatus, a modified object geometry may be determined, wherein a local modification of the object geometry is determined based on a local radiant heating parameter determined from the non-uniform radiant heating distribution.

Abstract: Certain examples described herein control an amount of a functional agent that is deposited in a three-dimensional printing system. In certain examples, an amount of a functional agent is controlled based on a distance function, wherein the distance function is associated with a distance between a particular portion of an object to be fabricated and a surface of the object. The functional agent may be a binder, a fusing agent or a detailing agent, amongst others.

Abstract: Apparatus (100) for generating a three-dimensional object comprising a support (101) to receive build material, and a calibration platform (103) to receive a print media for use with a calibration operation performed by the apparatus. The calibration platform (103) may be moveable between a non-calibration position when the apparatus is operating in a building mode of operation, and a calibration position when the apparatus is operating in a calibration mode of operation.

Abstract: There is disclosed additive manufacturing apparatus comprising: a controller to: receive object data relating to an object to be generated; and define print data for additive manufacture of the object by ejection of a print agent on build material in a pattern corresponding to selective fusing of the build material, wherein the print data is defined based on the object data so that the pattern defines a shield feature embedded within the object to inhibit fusing of build material corresponding to the shield feature relative build material corresponding to an adjacent portion of the object; and a print agent distributor to eject a print agent on build material based on the print data.

Abstract: There is disclosed additive manufacturing apparatus comprising: a controller (110) to: receive object data relating to an object to be generated; and define print data for additive manufacture of the object by ejection of a print agent on build material in a pattern corresponding to selective fusing of the build material, wherein the print data is defined based on the object data so that the pattern defines a shield feature (56) embedded within the object to inhibit fusing of build material corresponding to the shield feature relative build material corresponding to an adjacent portion of the object; and a print agent distributor (104) to eject a print agent on build material based on the print data.