A plastic shell such as an orthodontic aligner has an interior shape that substantially conforms to a current or future dental arch of a patient. The plastic shell includes a hollow feature comprising a cavity. The plastic shell additionally includes an object inserted into the cavity, wherein the object provides structural strength to the plastic shell at a location of the hollow feature and does not interfere with a fit of the plastic shell onto the dental arch of the patient.

An article of footwear includes an upper, a midsole connected to the upper, and an outsole connected to the midsole. The midsole includes a platform extending along a perimeter portion of the midsole and a lattice structure integrally formed with the platform, the lattice structure including a network of laths.

In one example, a print head drop detector (202) is described. The print head drop detector (202) comprises a sampling volume and a fan (208) to cause an airflow though the sampling volume (206). Detection apparatus to detect the presence of non-gaseous material within the sampling volume is also provided.

A part is fabricated by an additive manufacturing process while levitating in space. Constituent features of the part are formed by 3-D printing. A part levitation system allows the spatial orientation of the part to be manipulated relative to one or more print heads.

Adjustment of a halftoning threshold can, in an example implementation, include assigning a relative energy value, relative to a reference energy value, to a location of a build area and adjusting a halftoning threshold based on the relative energy value.

Agent calibration can, in an example implementation, include generating a calibration based on a quantity of energy absorbed by a build material treated with different quantities of an agent and converting a portion of a three-dimensional object model to a quantity of agent based on the calibration.

Methods of making metal objects are provided. These methods generally involve adding a metal powder slurry into a sacrificial mold, such as a mold made by three dimensional printing, and heating the slurry/mold mixture. The heating steps may include curing the slurry to make a green part inside the mold, debinding to burn off the mold and binder to make a brown part, sintering, and hot isostatic pressing. Metal products, such as aircraft engine parts, are also provided.

An additive manufacturing apparatus includes a table, an ejecting unit that faces the table and ejects photocurable droplets toward the table, a light-applying unit that applies light to and cures the droplets on the table, a moving unit that moves the table back and forth along with the light-applying unit and relative to the ejecting unit, and a controller that controls the ejecting unit, the light-applying unit, and the moving unit such that the ejecting unit ejects droplets toward the table while the table is moved relative to the ejecting unit; the light-applying unit applies, when a direction of relative movement of the table is changed, light to the droplets that have moved together with the table out of an area where the table faces the ejecting unit; and a three-dimensional object is formed as a stack of layers composed of the droplets that have been cured.

A shaping device, that shapes a three-dimensional object, includes an ink jet head that discharges an ink to become a material of shaping; and an ink supplying unit that supplies a pre-toned ink, which is the ink toned in advance in accordance with a color to be colored on the 3D object, to the ink jet head, where the ink jet head forms at least one part of the 3D object while coloring the one part with the color of the pre-toned ink by discharging the pre-toned ink.

A method for printing uses at least one bio-ink. The method also uses at least one laser print head to deposit at least one droplet of at least one bio-ink onto a depositing surface of a receiving substrate. The printing method uses at least one nozzle print head to deposit at least one droplet of at least one bio-ink onto a depositing surface of the same receiving substrate as the laser print head.