Abstract: In an example implementation, a sintering system includes a support structure in a sintering furnace to support a token green object during a sintering process. The system includes wires installed into the furnace and through the support structure to contact the object. An impedance meter is operatively coupled to the wires to determine electrical impedance of the object during the sintering process.

Abstract: In an example implementation, a sintering system includes optical fiber installed into a sintering furnace. A support structure inside the furnace is to support a token green object in a predetermined position and to hold a distal end of the fiber adjacent to the predetermined position. A light source is operably engaged at a proximal end of the fiber to transmit light through the fiber into the furnace. A light detector is operably engaged at the proximal end of the fiber to receive reflected light through the fiber that scatters off a surface of the token green object.

Abstract: According to one example there is provided a non-transitory computer readable storage medium comprising instructions that, when executed by a processor, cause the processor to: obtain an object model; analyse the object model; obtain characteristics of an interface agent; generate a modified object model comprising a support structure and an interface between the support structure and the object, the interface being such that after generation of a 3D printed green part and after sintering thereof, the support structure may be released with a predetermined force; and controlling a 3D printer to generate a 3D printed green part based on the modified object model.

Abstract: In an example implementation, a method of 3D printing includes receiving a 3D object model that defines the shape of an object to be printed in a layer-by-layer build process, and determining a desired thermal profile based on the shape of the object. For each object layer, a fusing energy radiation pattern is determined based on the desired thermal profile, and an electromagnetic energy emitter array is controlled to deliver fusing energy to the object layer according to the energy radiation pattern.

Abstract: In an example implementation, a sintering system includes a support structure in a sintering furnace to support a token green object during a sintering process. The system includes wires installed into the furnace and through the support structure to contact the object. An impedance meter is operatively coupled to the wires to determine electrical impedance of the object during the sintering process.

Abstract: According to one example there is provided a non-transitory computer readable storage medium comprising instructions that, when executed by a processor, cause the processor to: obtain an object model; analyse the object model; obtain characteristics of an interface agent; generate a modified object model comprising a support structure and an interface between the support structure and the object, the interface being such that after generation of a 3D printed green part and after sintering thereof, the support structure may be released with a predetermined force; and controlling a 3D printer to generate a 3D printed green part based on the modified object model.

Abstract: In an example implementation, a 3D printing system to remove components of a liquid agent includes a permeable surface. Build material formed on the permeable surface can be heated to generate vapor from a component of the liquid agent. The vapor can be drawn out of the build material through the permeable surface.

Abstract: In an example implementation, a sintering system includes optical fiber installed into a sintering furnace. A support structure inside the furnace is to support a token green object in a predetermined position and to hold a distal end of the fiber adjacent to the predetermined position. A light source is operably engaged at a proximal end of the fiber to transmit light through the fiber into the furnace. A light detector is operably engaged at the proximal end of the fiber to receive reflected light through the fiber that scatters off a surface of the token green object.

Abstract: Measuring an inkjet nozzle may include taking at least one impedance measurement after the firing command is sent to detect the presence of a drive bubble and taking another impedance measurement to detect a collapse of the drive bubble.

Abstract: In an example implementation, a method of 3D printing includes receiving a 2D data slice derived from a 3D object model, where the 2D data slice defines an object area of a layer of build material that is to receive a liquid functional agent and be fused as a layer of a part. The method includes determining that the 2D data slice distinguishes first and second tolerance zones within the object area. The method includes controlling a printhead to print a liquid functional agent onto the layer of build material according to a first droplet ejection spacing when printing in the first tolerance zone, and controlling the printhead to print a liquid functional agent onto the layer of build material according to a second droplet ejection spacing when printing in the second tolerance zone.

Abstract: A print head assembly (PHA) includes a microelectromechanical systems (MEMS) die mounted to a substrate with an application specific integrated circuit (ASIC). The die includes an opening defined in the die, a plurality of nozzles adjacent to the opening in fluid communication with the opening, and a pad to receive electrical control signals. The ASIC includes a communication link and a plurality of transmission lines that transmit electrical signals to the MEMS die.

Abstract: In some examples, a controller receives impedance sensor values from an impedance sensor in a printhead, determines whether the impedance sensor values correlate to a production of an effective drive bubble for the printhead, and issues a command to modify a firing parameter for a fluid ejector of the printhead based on the impedance sensor values.

Abstract: Measuring an inkjet nozzle may include taking at least one impedance measurement after the firing command is sent to detect the presence of a drive bubble and taking another impedance measurement to detect a collapse of the drive bubble.

Abstract: A printhead circuit for providing pulses for driving two or more actuating elements, the circuit comprising a cold switch drive circuit, for driving an actuating element for a first phase of a first pulse, the cold switch drive circuit having a cold drive switch for selectively coupling a drive waveform to the actuating element during the first phase according to a print signal; and a hot switch drive circuit, for driving the actuating element for a second phase of the first pulse, wherein the hot switch drive circuit is configured to drive the actuating element during the second phase according to an actuating element compensation indication signal.

Abstract: A print head assembly (PHA) includes a microelectromechanical systems (MEMS) die mounted to a substrate with an application specific integrated circuit (ASIC). The die includes an opening defined in the die, a plurality of nozzles adjacent to the opening in fluid communication with the opening, and a pad to receive electrical control signals. The ASIC includes a communication link and a plurality of transmission lines that transmit electrical signals to the MEMS die.

Abstract: Measuring an inkjet nozzle may include taking at least one impedance measurement after the firing command is sent to detect the presence of a drive bubble and taking another impedance measurement to detect a collapse of the drive bubble.

Abstract: An apparatus includes an amplifier to drive a piezo print nozzle in response to a bias current. A bias adjuster includes a plurality of side legs and a plurality of current mirrors. The bias adjuster varies the bias current in the amplifier based on a variable slew rate associated with an input signal of a print command. The bias adjuster is to selectively mitigate power loss and increase slew rate performance of the amplifier.

Abstract: In some examples, a printing system comprises a plurality of microelectromechanical systems (MEMS) dies comprising printing fluid jets, a printhead assembly (PHA) application specific integrated circuit (ASIC), and a substrate comprising the plurality of MEMS dies and the PHA ASIC. The PHA ASIC is to process image data into a plurality of data signals that define a firing pattern, and transmit the data signals through transmission lines on the substrate to the plurality of MEMS dies. The printing fluid jets of the plurality of MEMS dies are to fire in response to the data signals.

Abstract: In some examples, a method of regulating a temperature of a printhead includes charging, in a first state of a temperature regulator, an analog memory to a reference voltage that corresponds to a predetermined temperature of the printhead. The temperature regulator monitors, during a second state, the temperature of the printhead, the monitoring including measuring a thermal voltage representing an actual temperature of at least a first local area of a plurality of local areas of the printhead, and comparing, with a comparator, the reference voltage to the thermal voltage to obtain a comparison result for at least the first local area. Based on the comparison result, a series of warming pulses from a warming pulse circuit to at least the first local area is selectively enabled.

Abstract: An inkjet printhead device, fluid ejection device and method thereof are disclosed. The fluid ejection device includes a fluid supply chamber to store fluid, an ejection chamber including a nozzle and a corresponding ejection member to selectively eject the fluid through the nozzle, and a channel to establish fluid communication between the fluid supply chamber and the ejection chamber. The fluid ejection device also includes a pressure sensor unit having a sensor plate to output a voltage value corresponding to a cross-sectional area of an amount of fluid in the at least ejection chamber.