Abstract: Certain examples described herein relate to a carriage assembly for an additive manufacturing system. The carriage assembly comprises a movable carriage to move over a build zone of the additive manufacturing system, a thermal sensor device on the carriage to obtain thermal data associated with a region of build material in the build zone, radiation device on the carriage to apply radiation onto the build material. The radiation device is configurable between a preheating mode, to apply radiation onto the region of build material to raise a surface temperature thereof, and a fusing mode, to apply radiation onto the region of build material to selectively fuse at least part of the region of build material.

Abstract: In one example, a material dispensing apparatus comprises a plurality of material containers, wherein the plurality of material containers comprises a first set of material containers arranged to contain a first material and a second set of material containers arranged to contain a second, different, material, and each material container of the second set is located relative to a respective material container of the first set to form a pair of material containers. In use, the material dispensing apparatus is controllable to move across a build platform of an additive manufacturing system.

Abstract: In an example, a data unit includes a mounting to removably mount the data unit on a receiving portion of an additive manufacturing build material container, a data source to provide data comprising a plurality of additive manufacturing parameters and a communications interface to communicate with a reader of an additive manufacturing build material processing apparatus. The communications interface is to transmit data from the data source to the additive manufacturing build material processing apparatus.

Abstract: Examples of a 3D printing apparatus arranged to perform a print operation using build material, and methods of operating such a 3D printing apparatus, are described. In one case, a 3D printer is arranged to perform a print operation using build material whilst a build material temperature sensed by the printer is below a threshold temperature of the build material. The printer is arranged to obtain a threshold temperature indicator in advance of a respective print operation.

Abstract: Certain examples described herein relate to a carriage assembly for an additive manufacturing system. The carriage assembly comprises a movable carriage to move over a build zone of the additive manufacturing system, a thermal sensor device on the carriage to obtain thermal data associated with a region of build material in the build zone, radiation device on the carriage to apply radiation onto the build material. The radiation device is configurable between a preheating mode, to apply radiation onto the region of build material to raise a surface temperature thereof, and a fusing mode, to apply radiation onto the region of build material to selectively fuse at least part of the region of build material.

Abstract: Disclosed is a powder build material handling system for a three-dimensional printer. The system comprises a delivery system. The delivery system is to carry powder build material in a flow of gas from a powder build material supply. The delivery system is to filter the flow of gas to separate the powder build material from the flow of gas. The delivery system is to direct the filtered flow of gas to the powder build material supply to form a closed system.

Abstract: In one example, a material dispensing apparatus comprises a plurality of material containers, wherein the plurality of material containers comprises a first set of material containers arranged to contain a first material and a second set of material containers arranged to contain a second, different, material, and each material container of the second set is located relative to a respective material container of the first set to form a pair of materiel containers. In use, the material dispensing apparatus is controllable to move across a build platform of an additive manufacturing system.

Abstract: In an example, a method comprises controlling material dispensing by a material dispensing apparatus to output a layer of material onto a build platform. The material dispensing apparatus comprises a plurality of pairs of material containers, each pair of material containers movable along a path across the build platform, and comprising a first material container to dispense a first material and a second material container to dispense a second material, to output a band of material along the path, each pair of material containers being arranged with respect to each other pair of material containers to move along respective paths across the build platform to output respective bands of material forming a complete layer of material on the build platform.

Abstract: In an example, a data unit includes a mounting to removably mount the data unit on a receiving portion of an additive manufacturing build material container, a data source to provide data comprising a plurality of additive manufacturing parameters and a communications interface to communicate with a reader of an additive manufacturing build material processing apparatus. The communications interface is to transmit data from the data source to the additive manufacturing build material processing apparatus.

Abstract: In an example, a data unit includes a mounting to removably mount the data unit on a receiving portion of an additive manufacturing build material container, a data source to provide data comprising a plurality of additive manufacturing parameters and a communications interface to communicate with a reader of an additive manufacturing build material processing apparatus. The communications interface is to transmit data from the data source to the additive manufacturing build material processing apparatus.

Abstract: Certain examples described herein relate to build units that are physically connectable to at least one host apparatus of an additive manufacturing system. A build unit comprises at least one controllable device useable in an object building operation. In certain examples, the at least one device is controllable according to first control instructions originating from the at least one host apparatus when the build unit is physically connected to the at least one host apparatus. In certain examples, the at least one device is also controllable according to second control instructions generated independently of the at least one host apparatus when the build unit is not physically connected to the at least one host apparatus.

Abstract: Movement detection circuitry is provided for a moveable component of an apparatus having an encoder member having a plurality of spaced regions to cause a response by a first detector and a second detector on the moveable component. First and second detection signal detection signals are received respectively from the first detector and second detector by processing circuitry of the movement detection circuitry. At least one of the first detection signal and the second detection signal is sampled when the first detector and second detector move relative to the encoder member. An error due to any impairment to one the spaced regions of the encoder member is based upon a comparison between the samples from the two detectors. A movement characteristic of the moveable component is determined by the processing circuitry from at least one of the first detector samples and the second detector samples.

Abstract: Certain examples relate to encoding data into three-dimensional objects. In one case, a location of a set of terminals to be accessed on an outer surface of the object after fabrication is determined. A mapping between data to be encoded and an electrical property to be measured via a conductive coupling and an embedded electrical structure with the electrical property are determined. Control data is generated to instruct the fabrication of the object with the set of terminals and the embedded electrical structure.

Abstract: Examples of a 3D printing apparatus arranged to perform a print operation using build material, and methods of operating such a 3D printing apparatus, are described. In one case, a 3D printer is arranged to perform a print operation using build material whilst a build material temperature sensed by the printer is below a threshold temperature of the build material. The printer is arranged to obtain a threshold temperature indicator in advance of a respective print operation.

Abstract: Disclosed is a powder build material handling system for a three-dimensional printer. The system comprises a delivery system. The delivery system is to carry powder build material in a flow of gas from a powder build material supply. The delivery system is to filter the flow of gas to separate the powder build material from the flow of gas. The delivery system is to direct the filtered flow of gas to the powder build material supply to form a closed system.

Abstract: A method, control circuit and printing system to control data communications with a plurality of integrated circuits. The method comprises receiving a control signal indicating that a first integrated circuit in the plurality of integrated circuits has been connected to an interface; pausing data communication between a processor and a second integrated circuit in the plurality of circuits over a data bus; and sending an enable signal to transition a switch from an open state to a closed state to connect a power supply to the interface while data communication with the plurality of integrated circuits over the data bus is paused.

Abstract: In an example, a selection valve of a fluid supply system is disclosed. The selection valve selectively couples a source of pressurized air to one of first and second fluid supply cartridges, in the fluid supply system, to provide fluid to a printhead, the one of first and second fluid supply cartridges being coupled to the source of pressurized air at a time and other fluid supply cartridge being vented to the atmosphere. The selection valve includes a sleeve to provide interconnections with the source of pressurized air, the first and second fluid supply cartridges, and the atmosphere. Further, the selection valve includes a core disposed rotatably inside the sleeve to selectively couple the one of first and second fluid supply cartridges to the source of pressurized air and the other fluid supply cartridge to the atmosphere for switching the pressurized air between the first and second fluid supply cartridges.

Abstract: In an example, a data unit includes a mounting to removably mount the data unit on a receiving portion of an additive manufacturing build material container, a data source to provide data comprising a plurality of additive manufacturing parameters and a communications interface to communicate with a reader of an additive manufacturing build material processing apparatus. The communications interface is to transmit data from the data source to the additive manufacturing build material processing apparatus.

Abstract: Certain examples described herein relate to build units that are physically connectable to at least one host apparatus of an additive manufacturing system. A build unit comprises at least one controllable device useable in an object building operation. In certain examples, the at least one device is controllable according to first control instructions originating from the at least one host apparatus when the build unit is physically connected to the at least one host apparatus. In certain examples, the at least one device is also controllable according to second control instructions generated independently of the at least one host apparatus when the build unit is not physically connected to the at least one host apparatus.

Abstract: A method and apparatus to reconfigure a CAN bus network after a failure comprising providing the network with a control device and one or more node devices in a closed loop of CAN bus lines, detecting if there is a failure in the network and reconfiguring the network if a failure is detected. Reconfiguring the network when a failure has been detected comprises decoupling each of the plurality of devices in the network from the CAN bus line, configuring the network to terminate signals in a first device closest to the failure on one side of the failure, configuring the network to terminate signals in a second device closest to the failure on the other side of the failure and coupling a first side of each device with a second side of an adjacent device other than the first side of the second device and the second side of the first device.