Abstract: Provided herein are methods for supporting a 3D-printed article while it is being produced. The methods can include printing the support structure along with the article, where the article can be removed from the support structure after the production process. In some embodiments, a method includes: determining a concave hull from an article to be 3D-printed, wherein the article to be 3D-printed comprises a plurality of fibers; determining one or more support pillars for connecting the article to be 3D-printed and a support surface; and printing the one or more support pillars and the article to be 3D-printed together using a 3D printing method. Also provided herein are methods for determining the geometry of the support structure and the supported 3D-printed article produced by the methods described herein.

Abstract: Systems, methods, and new file formats are provided for printing 3D microstructures. In some implementations, a new file format is provided that defines 3D objects by a wireframe model expressed as a collection of wires. Because wires and their parameters are defined within the new file format, objects may be processed more efficiently and quickly to support 3D rendering operations. Such methods may be used to print new articles, such as eyelashes, bushes, swabs and other novel items.

Abstract: Systems, methods, and new file formats are provided for printing 3D microstructures. In some implementations, a new file format is provided that defines 3D objects by a wireframe model expressed as a collection of wires. Because wires and their parameters are defined within the new file format, objects may be processed more efficiently and quickly to support 3D rendering operations. Such methods may be used to print new articles, such as eyelashes, bushes, swabs and other novel items.

Abstract: A sensor may include a knitted pocket and loose yarn that is inside a cavity of the pocket. In some cases, this loose yarn is neither woven, nor knit, nor otherwise part of a fabric. A resistive pressure sensor may include a knitted pocket and loose conductive yarn that is inside the pocket. Pressure applied to the pocket may compress the loose yarn, which may increase the number of electrical shorts between different parts of the loose yarn, which in turn may decrease the electrical resistance of the loose yarn. A capacitive sensor may include a knitted pocket and insulative loose yarn that is inside the pocket. A strain sensor may include knitted conductive pleats. Electrical shorts may occur in contact areas where neighboring pleats meet. As the strain sensor stretches, these contact areas may become smaller, causing the electrical resistance of the pleats as a group to increase.

Abstract: Provided herein are systems and methods for printing a 3D object on a pliable substrate. In some aspects, the pliable substrate is moved through a vat of polymeric precursor while a mechanism (e.g., having opposing belts) maintains contact with the peripheral edges of the substrate. The systems and methods described herein can have certain advantages, such as precise control over the pliable substrate, allowing for precision printing of 3D articles.

Abstract: Systems, methods, and new file formats are provided for printing 3D microstructures. In some implementations, a new file format is provided that defines 3D objects by a wireframe model expressed as a collection of wires. Because wires and their parameters are defined within the new file format, objects may be processed more efficiently and quickly to support 3D rendering operations. Such methods may be used to print new articles, such as eyelashes, bushes, swabs and other novel items.

Abstract: Systems, methods, and new file formats are provided for printing 3D microstructures. In some implementations, a new file format is provided that defines 3D objects by a wireframe model expressed as a collection of wires. Because wires and their parameters are defined within the new file format, objects may be processed more efficiently and quickly to support 3D rendering operations. Such methods may be used to print new articles, such as eyelashes, bushes, swabs and other novel items.

Abstract: A modular structure may comprise multiple mechanical linkages. The structure may undergo two-dimensional or three-dimensional shape transformations, such as bending, twisting, shearing, uniform scaling, and anisotropic scaling. These shape transformations may be actuated by applying force to one or more specific locations in the structure. Each of the linkages in the modular structure may comprise a four-bar linkage. The exact shape transformation that the structure undergoes may be determined by the type and location of the linkages in the structure.

Abstract: Systems, methods, and new file formats are provided for printing 3D microstructures. In some implementations, a new file format is provided that defines 3D objects by a wireframe model expressed as a collection of wires. Because wires and their parameters are defined within the new file format, objects may be processed more efficiently and quickly to support 3D rendering operations. Such methods may be used to print new articles, such as eyelashes, bushes, swabs and other novel items.

Abstract: Systems, methods, and new file formats are provided for printing 3D microstructures. In some implementations, a new file format is provided that defines 3D objects by a wireframe model expressed as a collection of wires. Because wires and their parameters are defined within the new file format, objects may be processed more efficiently and quickly to support 3D rendering operations. Such methods may be used to print new articles, such as eyelashes, bushes, swabs and other novel items.

Abstract: A long sheet may travel lengthwise through a fabrication system. The sheet may be much longer than it is wide or high. One or more objects that are being fabricated may be attached to the sheet. The sheet may move, step by step, through a vat of liquid photopolymer while a digital micromirror device projects a sequence of images unto a surface of the liquid. At each step, a projected light image may cure liquid photopolymer, thereby producing solid, cured polymer that becomes part of an object being fabricated. The sheet may be included in the final fabricated object, or may be a sacrificial material that is removed from the final fabricated object. Alternatively, the sheet may be in the shape of a loop. Or, the sheet may be detached from the final fabricated object and then fed through the system again.

Abstract: A sensor may include a knitted pocket and loose yarn that is inside a cavity of the pocket. In some cases, this loose yarn is neither woven, nor knit, nor otherwise part of a fabric. A resistive pressure sensor may include a knitted pocket and loose conductive yarn that is inside the pocket. Pressure applied to the pocket may compress the loose yarn, which may increase the number of electrical shorts between different parts of the loose yarn, which in turn may decrease the electrical resistance of the loose yarn. A capacitive sensor may include a knitted pocket and insulative loose yarn that is inside the pocket. A strain sensor may include knitted conductive pleats. Electrical shorts may occur in contact areas where neighboring pleats meet. As the strain sensor stretches, these contact areas may become smaller, causing the electrical resistance of the pleats as a group to increase.

Abstract: A long sheet may travel lengthwise through a fabrication system. The sheet may be much longer than it is wide or high. One or more objects that are being fabricated may be attached to the sheet. The sheet may move, step by step, through a vat of liquid photopolymer while a digital micromirror device projects a sequence of images unto a surface of the liquid. At each step, a projected light image may cure liquid photopolymer, thereby producing solid, cured polymer that becomes part of an object being fabricated. The sheet may be included in the final fabricated object, or may be a sacrificial material that is removed from the final fabricated object. Alternatively, the sheet may be in the shape of a loop. Or, the sheet may be detached from the final fabricated object and then fed through the system again.

Abstract: A modular structure may comprise multiple mechanical linkages. The structure may undergo two-dimensional or three-dimensional shape transformations, such as bending, twisting, shearing, uniform scaling, and anisotropic scaling. These shape transformations may be actuated by applying force to one or more specific locations in the structure. Each of the linkages in the modular structure may comprise a four-bar linkage. The exact shape transformation that the structure undergoes may be determined by the type and location of the linkages in the structure.

Abstract: A computer produces a digital model that efficiently describes a dense array of many micro-pillars. The digital model achieves this efficiency by describing an entire micro-pillar with only a few parameters. For example, an entire micro-pillar may be described by two of more of the following parameters: height, base thickness, profile and tilt. The computer outputs instructions to fabricate the micro-pillar array, in accordance with the digital model. A 3D printer fabricates the micro-pillar array, based on the instructions. Applying vibration to a directional array of micro-pillars may cause the array of micro-pillars to actuate motion of a passive object that is touching the array. Also, a sensor may measure sounds caused by swipes against a micro-pillar array, and output signals indicative of the measurements. A computer performs a machine learning algorithm that takes the measurements as an input, and classifies the swipes.

Abstract: In exemplary implementations of this invention, a shape controller controls the shape of a bladder as the bladder inflates. The shape controller includes a first set of regions and a second set of regions. The second set of regions is more flexible than the first set of regions. The shape controller is embedded within, or adjacent to, a wall of the bladder. When the bladder is inflated, the overall shape of the bladder bends in areas adjacent to the more flexible regions of the shape controller. For example, the shape controller may comprise paper and the more flexible regions may comprise creases in the paper. Or, for example, the more flexible regions may comprise notches or indentations. In some implementations of this invention, a multi-state shape display changes shape as it inflates, with additional bumps forming as pressure in the display increases.

Abstract: A composite film includes a substrate that is not responsive to relative humidity, and also one or more layers of hygromorphic material. The hygromorphic material expands in response to an increase in relative humidity and contracts in response to a decrease in relative humidity. In some cases, the composite film is bi-layer or tri-layer. The composite films are fabricated such that they undergo a desired bending pattern in response to changes in relative humidity. In some cases, these bending patterns are combinations of two bending primitives: a smooth curve and a sharply angled curve. These two primitives are combined to create a variety of shape transformations including 1D linear transformation, 2D surface expansion and contraction, 2.5D texture change and 3D folding. Any type of hygromorphic material may be employed, including living gram positive and gram negative bacterial cells, yeast cells, plant cells, mammalian cells, cell debris, or hydrogel.

Abstract: A composite film includes a substrate that is not responsive to relative humidity, and also one or more layers of hygromorphic material. The hygromorphic material expands in response to an increase in relative humidity and contracts in response to a decrease in relative humidity. In some cases, the composite film is bi-layer or tri-layer. The composite films are fabricated such that they undergo a desired bending pattern in response to changes in relative humidity. In some cases, these bending patterns are combinations of two bending primitives: a smooth curve and a sharply angled curve. These two primitives are combined to create a variety of shape transformations including 1D linear transformation, 2D surface expansion and contraction, 2.5D texture change and 3D folding. Any type of hygromorphic material may be employed, including living gram positive and gram negative bacterial cells, yeast cells, plant cells, mammalian cells, cell debris, or hydrogel.

Abstract: Methods, systems, and apparatus, including medium-encoded computer program products, facilitate the design and use of 3D printed auxetic structures. In one aspect, a system includes one or more computer storage media having instructions stored thereon; and one or more data processing apparatus configured to execute the instructions to perform operations including (i) receiving an input specifying a three dimensional (3D) model of a 3D structure that includes at least two different materials having a predefined arrangement with respect to each other to give the 3D structure a negative Poisson ratio, (ii) receiving an input regarding a change for the 3D structure, and (iii) modifying the predefined arrangement of the at least two different materials with respect to each other in response to the input regarding the change.

Abstract: In exemplary implementations of this invention, a shape controller controls the shape of a bladder as the bladder inflates. The shape controller includes a first set of regions and a second set of regions. The second set of regions is more flexible than the first set of regions. The shape controller is embedded within, or adjacent to, a wall of the bladder. When the bladder is inflated, the overall shape of the bladder bends in areas adjacent to the more flexible regions of the shape controller. For example, the shape controller may comprise paper and the more flexible regions may comprise creases in the paper. Or, for example, the more flexible regions may comprise notches or indentations. In some implementations of this invention, a multi-state shape display changes shape as it inflates, with additional bumps forming as pressure in the display increases.