Patent ID: 12225924

DETAILED DESCRIPTION OF THE INVENTION

The present invention will be understood more readily by reference to the following detailed description of the invention and the accompanying figures, which form a part of this disclosure. This invention is not limited to the specific devices, methods, processes, elements or parameters described and/or shown herein and the terminology used herein is for the purpose of describing particular embodiments and is by way of example only and not intended to be limiting of the claimed invention. Any and all patents and other publications identified in this specification are incorporated by reference as though fully set forth herein.

Also, as used in the specification including the appended claims, the singular forms “a,” “an,” and “the” include the plural, and reference to a particular numerical value includes at least that particular value, unless the context clearly dictates otherwise. Ranges can be expressed herein as from “about” or “approximately” one particular value and/or to “about” or “approximately” another particular value. When such a range is expressed, another embodiment includes from the one particular value and/or to the other particular value. Similarly, when values are expressed as approximations, by use of the antecedent “about,” it will be understood that the particular value forms another embodiment.

The present invention's flour-based shape-changing materials, foods10, methods100, devices, computational design tools200and digital fabrication processes300introduce an integrated design strategy for making shape-changing flour-based foods10during either dehydration54(e.g. baking,FIG.30A) or hydration52(e.g. water boiling,FIG.30B) cooking processes.FIGS.30A and30Balso show the reliability and repeatability of producing food10of a desired or predetermined shape and bending angle42when utilizing the various embodiments of the present invention. This application includes a novel morphing mechanism—modifying the surface texture of dough20and more specifically, groove-induced differential swelling or shrinking; a design tool200(as shown inFIG.3); and a digital fabrication platform300(also shown inFIG.3) that are tailored to this novel mechanism.FIG.3Cshows a thin hair pasta noodle transforming into a dense coil when it is boiled (hydration52).FIG.3Dshows a sheeted square piece of dough20turning into a dried cannoli wrap when it is baked (dehydration54).FIG.1shows several applications of various embodiments of the present invention including: self-wrapping cannoli (FIG.1A); self-wrapping tacos (FIG.1B); self-folding multi-flavored cookies (FIG.1C); self-assembling noodles (FIG.1D); flat-pack hiking food10(FIG.1E); and shape customized pasta (FIG.1F).FIG.32Ashows a variety of designs of novel pasta shapes (straight grooves, curved grooves, grooves on both sides) in 2D and actual pasta (from top to bottom: bamboo, container, spring, folded, wave, ring saddle, twisted) before and after cooking and shows the actual results compared with the simulation results (which can be obtained by simulating the 3D shape230with a computation design tool200according to one embodiment of the present invention).FIG.32Cdemonstrates the utility of flat shape pasta transforming into fusilli pasta. Finally,32D and32E illustrate heart shaped pasta as a medium for communication enhancement.

The method100, design tool200and digital fabrication process300described offer three possible embodiments of ways to make shape-changing food10. The various shape-changing foods10are made from a flat piece of flour-based dough20, which has a top surface22and a bottom surface24. The flat piece of flour-based dough20is cut to a predetermined initial shape26and a predetermined initial size28. Additionally, the top surface22of the dough20has at least one set of parallel grooves30running perpendicular to a predetermined bending direction40on it. Optionally, the bottom surface24of the dough20has at least one set of parallel grooves30running perpendicular to a predetermined bending direction40on it. For any sets of parallel grooves30on either the top surface22or the bottom surface24, the grooves can cover all or part of the top surface22and/or bottom surface24. Finally, the at least one set of parallel grooves30has a groove depth32and a groove spacing34chosen to achieve a predetermined bending angle42or a predetermined final shape44. This grooved dough20is then exposed to a stimuli50, such as hydration52or dehydration54, which causes the flat piece of flour-based dough20to change shape or bend. This dough20can be made of one or more than one layers29of different doughs having different compositions and different thicknesses. The optional use of different layers29of dough20having different thicknesses, compositions, and/or different ratios of thicknesses impacts the bending angle42of the dough20and these factors can be varied to achieve predetermined bending angle42and/or predetermined final shapes44. Alternatively, any one of these factors can be varied to achieve a predetermined bending angle42and/or predetermined final shapes44. For example, the dough20can be comprised of layers29that have the same composition but different thicknesses or layers29that have different compositions but the same thicknesses or be made of only one layer of one composition of dough. The present invention's pastas and other flour-based foods10provide a traditional pasta and food taste, mouthfeel and cooking processes (hydration52and dehydration54) with entirely novel shape-changing properties. These novel foods10provide distinct advantages over prior shape-changing food technologies and new applications for shape-changing foods10.

Overview of Hydration Stimuli and the Impact of Grooving Generally: The present invention utilizes the impact of grooving110geometrical features into the microstructure of at least one surface of flour-based dough20(FIGS.5A through5C). Reference is made herein to flat, flour-based dough20, which has a “top surface”22and a “bottom surface”24. Alternatively, the phrases “first surface” and “second surface” are used herein. The use of the phrases “top surface”, “bottom surface”, “upper surface”, “lower surface”, “first surface” and “second surface” are relative terms and merely mean that the flat dough20has two opposing surfaces, which can be interchangeable, with at least one of the two surfaces having grooves thereon. A “top surface”22is generally referring to the surface that is exposed during the grooving process110. While the opposing “bottom surface”24is the surface that is resting on a support surface during the grooving process110. By flipping the dough20over, the “top surface”22becomes the “bottom surface”24and vice versa. The various embodiments of the present invention encompass grooving110either or both surfaces to achieve one or a plurality of predetermined bending angles42on a piece of dough20and/or to achieve a final shape44.

The grooving110of geometrical features on the surface of the sheeted dough20(thereby modifying the surface texture) controls and takes advantage of the differences between the swelling rate or dehydration rate of the material of the grooved and ungrooved surfaces, which causes the pasta/dough20to change shape. The grooves cause a difference in the speed of water swelling (or contracting) between the upper/top22and lower/bottom surfaces24, more specifically, the side with grooves has a slower water swelling rate than the side without the grooves. Grooves also provide space into which each peak can expand in both directions, while the side without grooves can expand much larger and/or faster without any interruption. When the peaks on both sides of the groove are close enough during the swelling process, the two peaks tend to stick together under the gelatinization of dough20, which serves to maintain the transformed shape.FIG.31Bshows the shape transformation of fusilli lunghi pasta (i.e., long spirals) before and after cooking. As the grooves collide, the released amylopectin causes them to adhere to each other. For both hydration52and dehydration54, the maximum bending angle42increases as the groove width decreases.

For many of the desired final shapes44for shape-changing food10illustrated in the figures associated with this application, the individual grooves in a set of grooves30are parallel to one another. However, the present invention does not require that the individual grooves in a set of grooves30be parallel to one another. The bending angle associated with an individual groove will be perpendicular to the longitudinal direction of the groove. The resulting or total bending angle or final shape44of a shape-changing food10will be the accumulation of the curvatures at each local point that is grooved on the dough20.FIG.35illustrates non-parallel grooves in the “Wing” shape and the “Ring” shape 2D designs.FIG.35also shows the corresponding photographs of dough20imprinted with those two non-parallel sets of grooves30designs. Similarly, given that the bending angle associated with an individual groove will be perpendicular to the longitudinal direction of the groove, bending of flour-based doughs or other materials can be achieved by the use of even one groove, instead of a set of grooves30.

For flour dough20, the morphing is irreversible. Pasta samples inFIGS.34A through34Dreached their maximum bending curvature between 10 to 20 minutes and remained three dimensional until the samples were overcooked and disintegrated. After 2 hours of continuous hydration52in 90° C., the bending curvature only had a 20% decrease. This irreversible shape assembly and shape-locking is due to amylopectin that leaks out of starch from the flour during cooking (FIG.31B) as a natural glue to partially fuse the colliding grooves (FIG.31BandFIG.36) and the irreversible gluten denaturation and starch gelatinization. To maximize the bending curvature, the viscoelasticity of the dough20was utilized to produce quadrilateral frustum shaped grooves with a stamping mold400that has cuboid shaped extrusions (FIGS.12A,12B and31A). Additionally, the design leveraged the irreversible morphing phenomenon of flour dough20for shape locking (FIG.36).

Overview of Dehydration Stimuli: The present invention encompasses a similar process via dehydration54. In the drying process, the same bending orientation performance takes place as the swelling process (FIG.5B) occurs. However, in the case of dehydration54, which has a longer deformation duration, the difference in the shrinkage rate between the side with and without grooves caused by the rate of thermal diffusion propagation is not the only reason for the change in the dough's shape. The side with grooves has a larger surface area which causes a higher shrinkage rate, while the surface without grooves has a smaller surface area which means a lower shrinkage rate. Additionally, higher temperatures can enhance the deformation effect, which brings additional value to the creation of a baking method for self-warping food10.

Computational Design and Fabrication—Parameterized Material Performances: The present invention's groove-induced shape-changing method100is effective for morphing flour-based food shapes. This is a novel method100to induce a shape-changing effect during both the hydration52and dehydration54processes, which involves modifying110the surface texture of the dough20and then exposing120the dough20to a transformational mechanism (such as a stimuli50) to induce a shape changing behavior. The method100for creating shape-changing food10, broadly diagramed inFIG.37, involves grooving110at least one set of parallel grooves30onto a flour-based dough20, having a top surface22and a bottom surface24, at an angle perpendicular to a predetermined bending angle42and at a groove spacing34and groove depth32chosen to result in a predetermined final shape44or the predetermined bending angle42and then exposing120the flour-based dough20a stimuli50to cause the prepared flour-based dough20to change shape. As illustrated inFIG.37, once the dough20is prepared it is then cut and/or grooved. The cutting316and grooving110steps are interchangeable in terms of the order in which they occur. Drying330the cut and grooved dough20is an optional step for those instances when the dough20is not going to be cooked immediately. Then, as shown inFIG.37, the cut and grooved dough20is exposed120to a stimuli50and then removed from the stimuli130,50when the ultimate bending angle42or shape44is achieved. When preparing shape-changing food10by boiling or baking, the dough20is then removed130from the stimuli50(boiling or baking) when it is finished being cooked and/or when the predetermined final shape44or the predetermined bending angle42has been achieved As illustrated inFIG.27, one embodiment of the design strategy implementing this method100involves creating flour-based morphing food10that is induced by dehydration54or hydration stimuli50.

To integrate the method100into the present invention's computational design tool200, design variables need to be parameterized. In the following discussion of experiments, certain design variables are described that can control the maximum, predetermined or desired bending angle42and the bending orientation(s)40of the sheeted dough20. These variables are integrated into a design tool200according to the present invention.

The experiments used plain dough20, egg white dough20and oat fiber dough20. The plain dough20was made with 112 g semolina flour and 43 g water. The egg white dough20contained 112 g flour, 9 g egg white, and 43 g water. The oat fiber dough20contained 112 g flour, 42 g oat fiber, and 125 g water. However, it will be obvious to one skilled in the art that the exact composition of the dough20used with the present invention can vary by type of flour (wheat, corn, rice, spelt, garbanzo, semolina, white, bread, pizza, pasta, cake, etc.) and type of liquid (water, egg, egg yolk, milk, juice, broth, etc.), the inclusion of other ingredients including but not limited to eggs, egg whites, salt, sugar, colorings, flavorings, etc., and the ratio of dry ingredient(s) to wet ingredient(s).

For the described experiments, the sample size (or initial shape26and initial size28) was 50 mm in length, 15 mm in width, and 2 mm in thickness. The mold400that was used to groove had a pitch distance of 1.5 mm. It will be obvious to one skilled in the art that other flour-based dough recipes will work with and are included in the present invention. Additionally, as explained more fully herein, it will be obvious to one skilled in the art that molds400having different pitch distances and groove depths32will accomplish different folding effects and all such variations of pitch distance (or groove spacing34) and groove depth32are included within the scope of this invention.

Groove depth32is an effective control parameter to determine the maximum bending angle42of the sheeted dough20.FIGS.4A through4Dshow that for the three chosen groove depths32, the deeper the groove depth32is, the bigger the maximum bending angle42is.FIG.4Ashows the groove depth32of different samples made with the same mold400.FIGS.4B through4Dillustrate maximum bending angles42of the samples during dehydration54(FIG.4B), hydration52(FIG.4C) and the groove depth32to average maximum bending angles42per unit length (FIG.4D). For the same samples, the average maximum bending angle42is bigger during the hydration process52than the dehydration process54. The results shown inFIG.4were achieved using plain dough20, made according to the previously-described recipe for the experiment.

Groove direction36determines the bending orientations. AsFIG.5shows, during both dehydration54and hydration processes52, the samples bend perpendicular to the directions of the parallel grooves30. For this experiment, the groove depth32was 1.8 mm and plain dough20was used.FIG.5Ashows parallel grooves30with varied angles to the edge of the rectangular sample.FIGS.5B and5Cshow how the varied angles bend along the direction of the grooves. These experiments showed that, for this particular composition of dough20, the preferred parameters are a groove depth32of about 1.8 mm, an initial dough thickness of about 2 mm, and a groove spacing34of about 1.5 mm. However, it will be obvious to one skilled in the art that the groove depth32, the groove direction36, the groove spacing34, the groove density, the groove direction36, the pitch distance, the dough composition and the initial dough thickness, size and shape can be varied to achieve any desired or predetermined bending angle42, desired or predetermined bending direction40and desired or predetermined final shape44, and all such combinations are included within the scope of this application. As demonstrated by the research explained herein, these factors are all interrelated and varying any one of the factors impacts the bending direction40, the bending angle42and the final shape44. Therefore, this application encompasses all variations and combinations of these factors to achieve any desired or predetermined bending direction40, the bending angle42and/or the final shape44.

While groove depth32is one of the most important factors in determining dough bending, groove density, groove distance and/or pitch distance also are factors that help to determine dough20bending and shape.FIGS.24A through24Dillustrate the effect of various groove densities on bending. As shown inFIG.24D, a pitch distance of 1.5 mm displays the best bending performance for both hydration52and dehydration54processes for the dough20tested under the conditions described herein. Therefore, most of the research conducted and explained herein utilizes grooves with 1.5 mm pitch distance.FIGS.24A through24Dalso demonstrates how the pitch distance and density can be varied to achieve more or less bending depending upon the desired or predetermined bending outcome for any given application of the present invention. Various manufacturing devices and techniques can be used to achieve greater or lesser pitch distances.FIGS.34A through34Dalso demonstrate the results of four of these factors on the morphing pasta. Pasta strips have different bending performance with varied groove width (FIG.34A), groove gap (FIG.34B), groove depth32(FIG.34C) and base thickness (FIG.34D).

Another factor described more fully herein is the impact of using single-sided or double-sided grooving patterns. Both positive and negative gaussian curvatures are achieved with either single sided or double sided grooving patterns (shown inFIG.35).FIG.35illustrates various morphing pasta samples as a design schematic and as a flat sample. The thickness of the samples shown inFIG.35is 2 mm.

Research on the present invention explored optimization of the maximum bending angle42by introducing a bi-layer29material composition in conjunction with the groove effect.FIGS.6A through6Cshow that by forming either flour and flour-egg white bi-layer29(egg white dough20), or flour and flour-oat fiber bi-layer29(oat fiber dough20), the maximum bending angle42can be further increased. For this experiment, the groove depth32was 1.8 mm.

In this experiment, egg white was chosen for its ability to harden when cooked due to the denaturation of its proteins at high temperature. As a result, the cooked egg white dough20has a smaller swelling rate than plain dough20. In contrast, oat fiber dough20has a higher swelling rate than the plain dough20.

Layer thickness is another variable. AsFIG.25shows, during the hydration process52, the sheet with a layer thickness at around 2 mm achieves the best shape retention after the sheet is taken out of water and the most significant or drastic bending angle42when the sheet is still in water. For this reason, the experiments conducted and described herein utilize 2 mm as the sheet thickness, but other thickness can be used and are included within the scope this application.

Different bilayer29thickness ratios were tested as another variable, whereby it was determined that a 1:1 layer29thickness ratio for egg white dough20and oat fiber dough20behaves the best for the dough composition being used in these experiments. Thus, a 1:1 ratio applies to all bilayer experiments discussed below unless noted otherwise.

Computational Design Tool200: One embodiment of the present invention is a computational design tool200that integrates design parameters and cooking guides to help users easily design and simulate shape-changing food10(broadly shown inFIGS.7A through7Eand diagramed inFIGS.38,39and40). More specifically, the design tool200implements the present invention's method100with a multi-step design flow, which steps can be displayed and controlled by an optional user interface. One embodiment of the computational design tool200has a 3D shape library210comprised of at least one 3D shape for flour-based foods10, from which library210the dough shape and/or the predetermined final shape44is defined or selected (FIGS.7A,39and40). This computational design tool200also has database212containing information on grooves and grooving parameters that correlates to each of the at least one 3D shapes for flour-based foods10(FIGS.38and40). From this database212the area of grooves and the grooving110parameters are set220(FIGS.7B and40). This embodiment of the computational design tool200also has a code generator214to produce code for production of the 3D shaped flour-based foods10. G-code or other similar code is generated240to control the machine(s) (FIGS.7D,38,39and40).

Another embodiment of a computation design tool200comprises an additional element of a simulator to simulate the 3D shapes (FIGS.7C,38,39and40). A further element of some embodiments of the computation design tool200is a fabricator to groove patterns onto a flour-based dough20. Finally,FIG.7Eillustrates one possible embodiment of a user interface for selecting control parameters for shape selection. One embodiment of the tool200compiles G-code for machine operation. Additionally, the code generator214further can generate an ingredient list242, dough preparation instructions244, and/or cooking instructions246and this code is used to control at least one machine in a digital fabrication process300. However, the design tool200is not limited to a particular code or machine language, and any code appropriate to the machine being used can be generated240and are included within the scope of this application.

One step or element of one embodiment of both the design tool200and the method100of the present invention involves determining the desired or predetermined final shape44. For the computational design tool200of the present invention, the first step involves the user choosing the dough shape. The second step is defining the groove parameters220. The third step is the design tool200simulating the final 3D shape230of the dough20after grooving110and exposure a stimuli120,50. The design tool200incorporates a shape library210, such as the library210illustrated inFIG.28, that correlates these three pieces of information (the initial dough shape, the grooving parameters, and the final dough shape).FIG.28Ashows a single set of grooves on a 2D sheet215.FIG.28Bshows multiple sets of grooves on a 2D sheet216.FIG.28Cshows multiple sets of grooves on a 1D line217. Based upon tests of the dehydration54and hydration52cases, it is possible to utilize multiple shape designs, including a single set215or multiple sets of grooves on a 2D sheet216or 1D line217, as shown inFIGS.8A through8C.

Second, some embodiments of both the computational design tool200and the method100can involve the utilization of fabrication instructions. Following the convention of a cooking recipe, one embodiment of the tool200generates instructions containing material ingredients242and illustrated manufacturing processes244,246, as shown inFIG.9.FIG.40illustrates how these fabrication instructions can be fed into a fabrication process.

Third, one embodiment of the method100and the design tool200involves preparing the dough310. This embodiment employs a manual or semi-manual process that is commonly used in traditional dough making. For one embodiment of the method100, this process310includes three steps—mixing312(FIGS.10A and10B), sheeting314(FIG.10C), and cutting316(FIG.10D). For the design tool200, the user can set ingredients before shape designing and the design tool200will generate the manual process guidance. First, all of the ingredients are placed in the bowl of a mixer at one time and mixed for 15 to 20 minutes. This step can be accomplished in a mixer capable of handling dough20or the dough20can be prepared by hand. When necessary, the dough20can be stored in a zipper bag or appropriate container to retain the dough's moisture until the sheeting process314begins. Second, for the sheeting process314, a roller sheeter (any capable sheeting machine or hand rolling pin) can be used to sheet the dough20up to 150 mm wide with 10 optional thicknesses from 0.6 mm to 4.8 mm (defined by roller No. 0 to 9 on the Marcato Atlas 150 Pasta Machine used for this research). Most of the experimental samples were 2 mm in thickness, which can be sheeted sequentially at thickness setting No. 0 for one time, No. 2 for one time, and No. 3 for three times. However, there are numerous known ways of sheeting314pasta that vary depending upon whether the sheeting314is done by hand, on a kitchen pasta maker or in a commercial-production setting. All such methods are included within the scope of this invention.

For the bi-layer29structures, two separately sheeted doughs20can be prepared, stacked and sheeted, using any of the previously mentioned processes. Doughs20that utilize more than two layers29can be prepared using a similar method. Finally, the dough20is cut into to an initial size28and initial shape26. It will be obvious to one skilled in the art that there are numerous automated and manual processes that can be used to prepare dough20for the present invention, and all such methods are included in the present application.

Grooving110is the third step in dough preparation. Different from common and existing dough processing steps, grooving110is a unique element of the present invention. Many embodiments of the present invention include pressing a customized mold400into the sheeted dough20to produce grooves, so that the dough20exhibits shape-changing behavior. Some examples of customized molds400are shown inFIGS.12and29. One embodiment of a mold400has a base410that connects the mold400to a grooving machine. Another embodiment of a mold400has a base410designed for hand-held use. Each of these molds400also has a grooving surface420designed to impart grooves of a desired groove depth32and groove spacing34onto the top surface22and, optionally, the bottom surface24of the dough20. For different embodiments the base410and the grooving surface420can be made from a single piece of material or they can be different pieces of the same or different materials that are connected by any appropriate means known in the art.FIG.12Ashows a grooving mold400with stoppers430for use with a manual process.FIG.12Bshows a grooving mold400with magnetic connections for use with a digital fabrication process300of one embodiment of the present invention.FIG.29shows variable molds400for shape customizability. However, the manual grooving method110has limited accuracy and repeatability. Therefore, another embodiment of the present invention comprises fabricating the groove patterns250with corresponding shape-changing motions with digital fabrication methods300. For the production of food, the grooving surface420should be made of an appropriate food-safe material. Additionally, the quality of the grooves and tips on the mold400impact the quality and character of the grooves made on the dough20. A mold400with sharp inverted V-shaped tips was used for the experiments described herein.

The present invention also encompasses a digital fabrication process300for creating shape-changing flour-based dough20. Similar to the method100and computational design tool200, the digital fabrication process300includes the steps of: (i) mixing312at least a flour and a liquid together to create a flour-based dough20; (ii) sheeting314the dough20by rolling the dough20to a predetermined thickness as measured between a first surface of the dough20and a second surface on the dough20; (iii) cutting316the dough20to a predetermined initial shape26and a predetermined initial size28; and (iv) grooving110the dough20on at least one of the first surface and the second surface to cause the dough20to bend when the dough20is exposed to a stimuli120,50. For some food products, the digital fabrication process300also can comprise drying330the dough20after grooving110the dough20.

Also, for some food products, the step of mixing312at least a flour and a liquid together to create a flour-based dough20can be performed more than one time to create more than one dough20and the step of sheeting314is performed on each dough20. These different doughs20will be layered on top of each other prior to cutting316the dough20to the predetermined initial shape26and the predetermined initial size28. For the digital fabrication process300, grooving110the dough20comprises grooving110at least one set of parallel grooves30into the dough20perpendicular to a predetermined bending angle42. One embodiment of the digital fabrication process300can include recording the data associated with the steps of mixing312, sheeting314, cutting316and grooving110the dough20.

The flowcharts inFIGS.39,40and41explain how the various embodiments of the present invention can be used together to go from selecting a desired design shape to producing the pasta to cooking the pasta. As illustrated inFIG.39, the digital design process (as embodied in the computational design tool200) involves inputting basic information regarding the desired shape, which is used to determine or select the groove design or grooving parameters. In some embodiments, the computation design tool200simulates the 3D shape. The information from this digital design process then can be fed into a digital fabrication process300, in which the dough20is prepared via the steps of: (i) mixing the raw materials/ingredients312, (ii) sheeting314the dough20, (iii) optionally drying the dough20for a brief period of time, (iv) grooving110and cutting316the dough20, and (v) optionally drying the dough20more completely to create a dried food product. This prepared dough20is then cooked by either boiling or baking.

The flowchart shown inFIG.40illustrates one embodiment of the computational design tool200in additional detail. Similarly, the flowchart shown inFIG.41illustrates one embodiment of the digital fabrication process300in greater detail. All three flowcharts illustrate how the computational design tool200can work with the digital fabrication process300to produce dough20that is ready to be cooked (and then is cooked). Additionally, all three flowcharts (FIGS.39-41) illustrate and describe, through narrative labels, additional steps, inputs, outputs, substeps and details, which are discussed in greater detail throughout this application and which can be included in some embodiments of the method100, computation design tool200, and fabrication process300of the present invention but are not necessarily required in all embodiments.

One possible embodiment of each of the method100, design tool200and digital fabrication process300uses a four degree of freedom grooving platform that was created by modifying a 3-axis CNC milling machine (Inventables X-carve 750 mm×750 mm) which is controlled by an X-controller and a 3D carving motion controller kit distributed by Inventables. Similar machines are inFIGS.3B and31A, which show a stamping method controlled by an automated machine gantry to create surface grooves on sheeted pasta dough20. It will be obvious to one skilled in the art that any machine with similar properties and abilities can be converted and/or used to accomplish the present invention's goals. This machine is compatible with the present invention's design software (seeFIGS.3A and3B). It can take the G-code toolpath compiled by the design tool200and execute the grooving task110. The spindle of the original milling machine was replaced with the present invention's novel customized servo cast that mounts a 55 g Metal Gear Servo connected vertically with a novel customized grooving mold400according to the present invention. A user can switch the mold400to another one with a different size or pitch distance according to the target transformation (as shownFIG.11A).FIG.11Aillustrates a CNC machine equipped with a rotational tool head with a replaceable grooving mold400. The customized tool head can groove the pasta dough20in various directions with 180-degree rotation range.FIGS.11B and11Cshow a grooving sequence with varied grooving angles.FIG.11Bshows a tool head moving through a cycle of rotating and grooving110according to the design.FIG.11Cshows the result of the automatic grooving110. In order for a user to adjust the servo rotation angle, one embodiment of the present invention uses the spindle PWM port of the original X-controller setup. Embodiments utilizing this grooving platform and related equipment map the range of the PWM (pulse width modulation) signal to the range of a signal to control the servo rotation angle by using an external microcontroller connected with the X-controller and the servo. The microcontroller is programmed to read the PWM signal and to convert it according to the mapped range. Then, the converted digital signal is transmitted to the servo motor, which allows a user to control the servo via the X-controller by the command originally designed for setting the spindle speed. One embodiment of this process is illustrated inFIG.41.

The newly sheeted dough20can be sticky, and the mold400can stick to the dough20once pressed. There are some optional steps that can be incorporated into various embodiments of the method100, design tool200and digital fabrication process300to address this. To minimize this, the sheeted dough20is allowed to air dry for five minutes after sheeting314, or whatever time is appropriate for the conditions of the dough20and the surrounding environment, to minimize sticking (see the “shortly drying” step inFIG.39). Sprinkling flour on the mold400before pressing can prevent the dough20from sticking to the mold400as well. Additionally, cutting316the dough20with a roller cutter before or after the grooving110can be required depending on the target contour. For rectangular shapes, the most effective way is to cut a long strip with calculated width firstly, and then groove it with the mold400. However, different shapes can require different cutting process316.

For most embodiments of the present invention, the steps of grooving110and cutting316are interchangeable with respect to the order in which they are performed. By using high quality cutting blades, there is little impact of the cutting process316on the quality of the grooves (generally, cutting does not dull or compact the edges of the grooves). However, in limited circumstances it can be found that cutting316the dough20before grooving110will stretch the dough20and, thus, change its target contour. So, in those instances it can be preferable to groove110the dough20before cutting316it.

To achieve the various goals of the present invention, grooving molds400are designed according to the predetermined or desired groove depth32, direction and density. Certain types and compositions of dough20will require the use of small pitch distances and sharp tips on the mold400to achieve high-quality—fine and sharp—grooves on the dough20, and the quality of the grooves will consequentially affect the quality of the transformation performance. To quickly iterate and test the design parameters of the molds400, one embodiment of the present invention utilizes 3D printed molds400with an Objet printer (Objet24) with a 16 μm printing resolution setting. A food grade mold release (CRC 03311) is used to make the fabricated molds400of the present invention food safe. It will be obvious to one skilled in the art that there are other comparable printers, tools and methods100for creating molds400according to the present invention.

For one embodiment of the mold400and method100, the optimized groove of the mold400is 3 mm deep with a 1.5 mm pitch distance. Since the groove depth32tends to vary depending on the applied pressure, stoppers430can be added to both sides of the mold400to maintain consistency of the groove depth32during the manual grooving process110(shown inFIG.12A). In the digital fabrication process300, a part modularization method was adopted to easily switch customized molds400with magnets (as shown inFIG.12B); however, other methods for attaching and switching molds400can work and are incorporated into the present application.

Drying330: This step is necessary only when dried flat food10is desired for the hydration-based transformation52. For example, commercial pasta is often dried to prolong the shelf life. Depending upon the composition of the dough20some hydration can need to be included in the drying330process to prevent the grooved dough from cracking. This additional hydration can be accomplished by introducing a mist of water or a bit of steam in the drying process. All of the shape-changing mechanisms of the present invention work for both fresh and dried dough20.

One drying method330is shown inFIG.13. This process takes 12-24 hours. The cover and the base plate with mesh holes are aimed to accelerate the process by allowing large airflow to contact with the sheeted dough20. Any other acceptable drying method330can be used as well and many are known within the art.

Dehydration-based Transformation—Setup: AsFIG.14shows, a convection oven (Oster) is one example of a dehydration54cooking (i.e. baking) environment that can be used with the present invention. It will be obvious to one skilled in the art that many different kinds of ovens and heat sources will work with, and are incorporated into, the present application. For example, a low-speed and convection-based dehydration process54enhances the bending performance. Thus, the oven can be set to 200° F. with turbo convection function under bake mode, and the oven kept open with a fan to accelerate air movement. Other temperatures and times can need to be used with different ovens, doughs20, environments and dehydration methods54. Over a period of 90 minutes, the deformation behavior started in around 4 minutes, and the maximum deformation behavior occurred in about 45 minutes.FIG.14Ashows wet samples in the oven after 11 seconds of baking.FIG.14Bshows samples that have been transformed after 45 minutes of baking.

Applications—Self-wrapping tacos and cannoli:FIG.15shows the preparation process and the final shape44of baking-induced self-wrapping covers made of flour dough20according to one embodiment of the method100. This method100starts with flat shape dough20and saves the preparation efforts.FIG.15Aillustrates self-wrapping tacos andFIG.15Billustrates self-wrapping cannoli.

Multi-Flavored cookies: Various embodiments of the present invention involve the use of composite dough20with different flavors and nutrition components.FIG.16shows that different types of dough20can work as raw materials for self-folding baked food10.FIG.16Aillustrates the preparation process of self-folding cookies with different flavors and nutrition contents.FIG.16Bfurther illustrates the final shape44of the cookies ofFIG.16Aafter baking.

Hydration-based-Transformation—Setup: AsFIG.17shows, an induction cooker (Rosewill RHAI-13001) can be used as the hydration cooking (i.e. boiling)52environment. It will be obvious to one skilled in the art that many different types of cookers, stoves, stovetops, hotplates and heat sources can also be used for the present invention and the cooking times can need to be adjusted for each cooking environment. Using the same method as for pasta, the water is boiled and the pasta is placed into the pot for 12 to 15 min. The transformation begins shortly after the pasta enters the boiling water (FIG.17A), reaching its maximum bending angle42after about 12 min (FIG.17B), and retaining the angle within 20 min. Hence, users can decide when to stop the cooking depending on the preferred and/or desire mouthfeel.

Flat-pack for Mountain Hikers: Various embodiments of the present invention include at least four transformation types for flat packed hiking food10. In previous work, Transformative Appetite envisioned a scenario involving shape changing gelatin-based food flat-packing. The present invention brought this vision into reality. One embodiment of the present invention includes four examples of semolina flour-based pasta that can save packing spaces ranging from 41% to 76% (shown inFIGS.18A through18D).FIGS.19A through19Gshow that the food10was cooked and consumed in an outdoor environment with a compact gas heater.

Self-assembling Noodle Balls for Accessibility: The shape-changing property of noodles made according to the present invention suggests a new type of eating experience for those who have difficulty using common utensils including forks and chopsticks. For example, a pile of thin noodles with a wood stick can be transformed into a lollipop-shaped noodle ball so that children who have not learned how to use forks can handle eating long noodles. With this method, they can easily hold the stick and feed themselves (as shown inFIGS.20A through20D). The present invention leverages the advantages of shorter cooking time and flat-packing capabilities, in addition to the post-assembled shape to improve accessibility for the young, handicapped and the elderly.

Edible Information Display: Pasta noodles made according to the present invention can be transformed on the dining table while they are being served, potentially providing a rich platform for diners to experience interactive information delivery. This interaction provides different types of information by, among other things, heating a metal plate that is responsive to various kinds of stimuli, like music. With this platform, people can send messages served on dishes. Various embodiments of the present invention incorporate, but are not limited to, the following scenarios: a metal plate containing uncooked angel hair noodles is served to a diner's table. A violinist comes to the table and plays a song, Salut d'amour'. Upon recognizing the song, the heating table begins heating the plate. The pasta cooks on the heated plate within 5-6 minutes and changes into a heart shape, conveying a message of love from the diner's partner (shown inFIG.21A).FIG.21Bshows that customized texts can appear as lines are being cooked.FIGS.22A through22Cillustrate how the heart shape was designed, simulated, and put in action as it was cooked.FIGS.22and22Bshow a design tool200to customize220and simulate230the transformation of food10for a special event.FIG.22Cillustrates the actual transformation behaviors of the dough20.

These novel foods10provide distinct advantages over prior shape-changing food technologies and new applications for shape-changing foods10. For example, some embodiments of the present invention hold sauce better than the traditional pasta because of its bent shape. As a result, shape changing pasta10tastes more savory and can be created to have more elastic and volumetric texture than traditional pastas or previous shape-changing foods10. Additionally, it can be easier to hold the shape-changing pasta with utensils because of its resilient texture and curved shape. The present invention's pastas have a more traditional mouthfeel than previous shape-changing pastas; however, the present invention's pasta with the same thickness can need to be cooked for one or two minutes longer than normal pasta to achieve an al dente consistency. This is due to the groove structure on the surface of the pasta of the present invention.

The present invention opens up multiple design spaces for shape changing food10, some examples of which are shown inFIGS.26A through26C. As shown inFIG.26A, the present invention provides space-saving advantages because of its flat-packing and multi-flavor options. Additionally, there is the novelty of the morphing processes of self-folding, self-wrapping-self-assembly and self-chopping (FIG.26B). Finally, he novel shape-changing attributes of the present invention create a new food entertainment experience, as exemplified inFIGS.23A and23BandFIG.26C. Diners can watch pasta transform its shape in the boiling water and showcase the cooking process at parties as a performance. Additionally, the present invention's shape-changing foods10have the ability to deliver visual information. Pastas according to the present invention can be shaped to represent different characteristics including flavor, nutrition, or even cooking time. For example, creating pasta that utilizes letters as visualization cues. A few nonlimiting examples might be an S-shaped pasta that is “sweet”, a U-shaped pasta that is “umami”, or a G-shaped pasta that is “gluten-free”. Additionally, a cook can easily tell if the pasta is ready to eat when the pasta reaches its target shape, which negates the need for tasting the pasta during the cooking process. Alternatively, the pasta can be programmed to transform from the flat shape to an R-shape when it is “ready” to be served. The present invention's pasta can even be customized to a customer's requested shape. Foods10prepared according to the present invention also can be designed to reduce the hands-on time or preparation time of certain foods. For example, when preparing dishes that form a container, i.e. wraps or dumplings, traditional preparation methods involve additional time to fill and close the wraps. Wraps and dumplings according to the present invention can be designed to self-wrap and eliminate this step in the traditional preparation process. Some examples of this aspect of the present invention are shown inFIG.15andFIG.17.

As suggested previously, foods10prepared according to the present invention enable flat-packed foods10to have a wider variety of shapes when cooked. For example, when hiking on long duration trips, the weight, package size, and packaging and product shape become important to efficient packing and to the ability for hikers to get rid of food and make their packs lighter as the trip progresses. At the intersection of these constraints and the available equipment, there lies an opportunity for the implementation of the present invention's shape changing pasta. Packaging for food10made according to the present invention can be both flat and efficient because the food10starts out with a flat shape. However, the present invention's foods10can be designed to cook up into a variety of different shapes using traditional camping and hiking equipment. This provides hikers with food variety previous unattainable in efficiently packed food products.

In modern society, a large portion of food is produced remotely and shipped to customers, resulting in pollution to the air due to the emissions of greenhouse gases to the environment. The flat-packed food10of the present invention helps to alleviate pollution by reducing the amount of air shipped during food transport (FIGS.18,32B and33). Contributing to sustainable food packaging, the morphing pasta saves 41% to 76% packaging space compared to conventional three dimensional pasta (FIGS.18,32and33). Take a package containing short macaroni pasta as an example (FIG.32B), the densest packing of tubes (side view of the pasta) in the plane is the hexagonal lattice of the bee's honeycomb. The packing density (θ) can be calculated to establish that 67.3% of volume in the package is air. The present invention takes flat-pack pasta and transforms it into 3D shapes during cooking, therefore, more than half of the space during shipping and storage will be saved. For the helical shaped pasta packaged as a hiking food10(FIG.19), this flat-pack approach can save up to 72.9% of packaging space.

The application demo previously described inFIG.19demonstrates this idea that the present invention is, among other things, a novel and simple mechanism for morphing flour-based dough20, during either the dehydration54or hydration52cooking process. The various embodiments of the present invention include these novel dough20and food products10, a customized design software and a digital manufacturing platform and novel food molds400. Applications are developed to indicate the potential design space for flour-based shape-changing food10, as shown inFIG.32B(illustrating a calculation on the space saved from 2D to 3D morphing). Both baked and boiled foods10are designed with shape-changing behaviors. Beyond the realization of flat-pack authentic pasta, the present invention also encompasses novel use-case scenarios including food10as an information display, food10that transforms for accessibility, and food10that self-wraps and saves the effort of preparation and cooking. On a higher level, the present invention illustrates how food can become media that transforms and interacts with cooks and diners (FIGS.23A and23B). By pushing the utilization of authentic and natural food ingredients, the present invention can be adapted further for real-world use and commercialization.

Applications Beyond Food: As will be explained more fully herein, the present invention includes non-food self-morphing materials60, a method100for creating self-morphing materials60, a computational design tool200for the creation of self-morphing materials60, a digital fabrication process300for making self-morphing materials60and molds400for making self-morphing materials60. Again, “morphing”, “self-morphing”, “self-folding” and “shape-changing” are used interchangeably in this application. The above-identified food-related method100, computational design tool200, digital fabrication process300and molds400can be used to create non-food self-morphing materials with a few modifications to address the needs of the initial material70or initial materials70being used. Similarly, as discussed more fully herein, a wide variety of self-morphing materials60can be created by grooving110the surface(s)22,24of a flat or three-dimensional piece of material70and exposing120the material70to a stimuli50or by grooving110, molding, casting, and/or extruding a grooved-surfaced material70. Depending upon the initial material70, the stimuli50might include but not be limited to hydration52, dehydration54, heat, cold, or an appropriate solvent. As with the food-based shape-changing materials, the stimuli50is chosen to take advantage of the differential in swelling or shrinkage (deswelling) between a grooved surface and a ungrooved surface on a material.

Additionally, this application describes a swelling-based morphing mechanism with real life applications. A universal rule of morphing is that, due to asymmetric swelling, morphing puts few restrictions on materials types used as long as they can swell and deswell in solvents or when exposed to other stimuli50. Parametrically controllable morphing is achieved by creating surface grooves30with simple stamping and molding methods and easy-to-access materials including silicone rubber (as shown inFIG.42A). Stated another way, by controlling one or more of the dough or grooving paraments, such as groove width, groove depth32, groove spacing34, initial material thickness, initial material size28, initial material shape26, the angle of the groove(s), one can control the bending direction40, the bending angle42and/or the final shape44of the self-folding material60. By integrating experiments with the use of a polymerical gel model, the temporal morphing is shown to be governed by the asymmetric swelling and deswelling that occurs in surfaces that are grooved and in surfaces that are ungrooved and time-lag in the diffusion process (seeFIG.42B, which shows a schematic morphing mechanism caused by surface grooves30of a strip). The deployment step involves immersing the grooved initial material70into a solvent or taking the swollen self-folding material60out of the solvent upon which the morphing occurs at a time scale controlled by the solvent diffusion process. The accessibility of the manufacturing methods, the versatility of the material types, and the lack of a multi-material composition requirement to achieve morphing allows many potential applications in daily life.

It is generally known that surface structures can alter the diffusion process when materials are immersed in certain solvents. The present application explains how geometrical factors of groove patterns and material properties control the morphing structures through tightly coupled large scale simulations and well-controlled experiments. The results reported here can be leveraged effectively to parametrically control the transformation morphology of a wide variety of materials subjected to a wide variety of stimuli by controlling one or more of the grooving or dough parameters.FIG.43Ademonstrates measured and simulated radial swelling ratios as a function of time for flour-based dough and PDMS disks (Polydimethylsiloxane (more specifically for these experiments Sylgard 184 from Dow Corning)). The initial sizes28are 25.2 mm in diameter and 2 mm in thickness for the pasta disks, 16 mm in diameter and 1 mm in thickness for the PDMS disks.FIG.43Bshows the maximum bending angle42increases as the groove width decreases for the sample of flour dough by showing the measured and simulated bending curvatures of pasta strips with different groove widths.FIG.43Cillustrates the effect of the tilting angle of the groove walls by showing the bending configurations of strips with quadrilateral frustum and cuboid shaped grooves30. The quadrilateral frustum shaped grooves30provide a bigger maximum bending angle42than the cuboid shaped grooves30because the groove walls in the cuboid shaped grooves30will collide with each other during bending deformation, which, in turn, prevents large bending angles42. Additional controlling factors include groove distance34(FIG.32B), groove depth32(FIG.34C) and the base (or material) thickness (FIG.34D).

FIG.43Dshows the experimental and simulation results of swelling (in solvent) and deswelling (in air) of the grooved PDMS strips.FIG.43Eshows the bending curvature of the PDMS strip samples and resulting simulation.FIG.43Fshows a simulation of swelling ratios at different regions of the PDMS strip samples.

The manufacturing process for non-food materials is similar to that for the flour-based dough (described above). The method100described herein was studied on a single homogeneous material (FIG.32), but layered materials can be chosen to work as well. Grooves of varying widths (micrometers to millimeters) are easily fabricated according to the method100, computational design tool200, and digital fabrication process300described herein and, for non-food materials, with low-cost manufacturing methods including stamping (FIGS.31A and11A through11C), molding and casting (FIG.12A), laser etching, extruding, 3D printing, additive manufacturing, and other similar methods known to those with skill in art. In particular, the stamping and casting methods introduced inFIGS.31A and42Aare suitable for materials with different visco- and elastic-behaviors and can accommodate quick changes in material compositions with additional dye, layer variations and modulus changes. For liquid material solutions such as silicone and hydrogel, casting or soft lithography methods can be used to create grooves30with a width of down to 500 μm (FIG.42A). Other methods can be used to create larger or smaller grooves30.

To describe the generalization of the morphing mechanism, and demonstrate the extended bi-directional and reversible morphing behaviors, experiments were conducted with PDMS.FIG.44shows the operations of various PDMS-based shapes that undergo bi-directional and reversible morphing behaviors when the shapes are taken in and out of the solvent. Depending upon the grooving patterns and the overall shape of the samples, three-dimensional geometries can be achieved that are developable sheets (FIG.44A through44D), non-developable sheets (FIG.44E) and volumetric shapes (FIG.44F). These material examples confirm that simple surface grooving110with relatively low resolution (0.5 to 1.5 mm as the gap distance) can serve as bi-directional, multi-stage and reversible morphing systems, which provide potential applications in gripping, manipulation and locomotion for robotics and biomedical uses.

More specifically,FIG.44shows bi-directional and reversible swelling and deswelling of silicone elastomers for controllable transformation.FIG.44Ashows how initially flat frangipani flower petals bend down when swelling and up when deswelling.FIG.44Billustrates how a rose flower self-folds when swelling and returns flat with petals bending upwards when deswelling.FIG.44Cis a linear strip with perpendicular grooves that forms a flat spiral with opposite bending directions40during a swelling-deswelling cycle. InFIG.44D, a linear strip with tilted grooves is shown. It can form a three-dimensional spiral when swelling and uncoil to the opposite side when deswelling.FIG.44Eshows how concentric grooves induce morphing of a flat sheet into a non-zero gaussian curvature surface with multiple local minima.FIG.44Fillustrates that grooves can be casted vertically along the walls of a cup-shaped cone and cause the flat top of the cup to morph into a concave polygon when swelling and convert polygon when deswelling (scale bar: 10 mm for all ofFIG.44).

Additionally, and as explained in the previous sections with respect to food-based shape-changing materials, the present invention does not require that the individual grooves in a set of grooves30be parallel to one another. The bending angle associated with an individual groove will be perpendicular to the longitudinal direction of the groove. The resulting or total bending angle of a self-folding material60will be the accumulation of the curvatures at each local point that is grooved on the initial material70.FIGS.44A,44B,44E and44Fillustrate some non-parallel groove sets30imprinted on silicon elastomers. Similarly,FIGS.46A,46B,46E and46Fillustrate patterns of non-parallel grooves.

For the experiments described herein, the trigger solvent for the PDMS experiments is diisopropylamine. It will be obvious to one skilled in the art that an appropriate solvent or stimuli50should be selected for the material that is to be grooved and morphed. As explained above for the flour-based food molds400, molds400for non-food materials can be cast out of appropriate materials, including but not limited to polylactic acid, and/or a 3D printed material. Again, when 3D printing a mold400, the quality of the mold tines and/or edges is important. For the molds400created for these experiments, the printing setting is set to “extra fine” quality to achieve clean lines and edges. However, different settings can be used depending upon the 3D printer used, the material being printed and the desired edge quality.

Also, for the experiments discussed and shown herein, and to start the casting process, the PDMS base and curing agent were mixed in a 10:1 ratio using a centrifugal mixer (AR-100 Thinky Mixer, Thinky U.S.A., Inc.). The prepared material was slowly pulled into the cast mold400and cured in the mold400for 12 hours. To prepare a fluorescent PDMS sample, 0.05 mL of the fluorescent dye (Silc-Pig™ Electric, Smooth-On, Inc.) was dispensed into 20 mg of PDMS before the thorough mixing. It will be apparent to one skilled in the art that other materials and curing agents can be combined to achieve different results.

For the PDMS samples with diisopropylamine as the triggering solvent, the swelling begins shortly after the PDMS sample enters the solvent, reaching its maximum bending angle42in about 6 minutes. Since the solvent evaporates rapidly in the air, the deswelling begins shortly after the PDMS sample is removed from the solvent, bending back to a flat state in about 2-3 minutes. The sample then continues to reversely bend to its maximum bending angle42in about 1-2 minutes and starts to recover with a decreasing bending angle42and volume until it is back to its initial state a few hours later.

FIGS.46A through46Fillustrate various morphing PDMS samples. In each case, a design schematic in 2D, a 3D model and detailed groove dimensions are shown inFIG.46. Some materials can require the use of a two-part 3D mold400with grooves on one or both sides, depending upon the final bending angle42and final shape44that is desired.FIG.47shows one example of an outer mold450(shown in cross section), an inner mold440, and a molding method (injecting PDMS into the mold400) according to one embodiment of the present invention.

During the development of the new grooving process110, a coupled diffusion and deformation model of polymeric gels was adopted to simulate the dynamically morphing of pasta during cooking. The key equations of the theoretical model are described in Chestera, S. Di, C. Anand, L.,A finite element implementation of a coupled diffusion-deformation theory for elastomeric gels(https://doi.org/10.1016/j.ijsolstr.2014.08.015), and are discussed below. The basic fields related to this theory can be found in the table inFIG.45A.

The governing equations of the polymeric gels include the balance of forces and balance of fluid concentration. For the balance of forces, the governing equations are
divT=0,  (Eqt. 2)

with the Cauchy stress T is given by
T=J−1[G(B−I)+K(lnJe)I],(Eqt. 3)

where G and K are shear and bulk modulus, respectively. Here the body forces are neglected.

For the balance of fluid concentration, the governing equation is
ċR=−Jdivj,  (Eqt. 4)

with j=−mgradμ and the chemical potential given by
μ=μ0+Rϑ(ln(1−ϕ)+ϕ+χϕ2)Js-1ΩK(lnJe),  (Eqt. 5)

where R is the gas constant, ϑ is the temperature, χ is the Flory-Huggins interaction parameter, and m=Dc/(Rϑ) with D representing a diffusion coefficient.

Since the structures could freely deform in experiments performed, displacement boundary conditions were not assigned in the simulations. The swelling and deswelling processes were modeled by prescribing a time-dependent chemical potential at the outer surfaces of the structures
μ̌=μ0+μ0exp(−t/td),  (Eqt. 6)

where tdis a characteristic time scale associated with the structure surface interaction with the environment and treated as a fitting parameter in the experiments to match the temporal morphing of the structures. From numerical tests, it was found that the steep change in the chemical potential in the deswelling process will cause convergence issues of the simulations. To overcome this, the chemical potential change near the starting point of deswelling was smoothed with the Fermi-Dirac function.

The governing equations in Eqs. (2-6) were solved by the finite element method through a user-defined element (UEL) in ABAQUS/standard. From the numerical tests that were performed, it was found that the UEL works very well for relatively stiff materials, like PDMS and can also capture the structure collision. However, numerical convergence issues were encountered for very soft materials, like flour-based doughs. Therefore, the finite element schemes in FEniCS were implemented to solve the governing equations. Although the FEniCS can resolve the numerical convergence issues for very soft materials, it cannot handle the structure collision. Therefore, there was a need to utilize both ABAQUS and FEniCS to capture the morphing of PDMS and pasta, respectively. For the simulations, the meshes were generated by importing the CAD files used in creating grooved structures in experiments to a mesh generation software (ABAQUS and Gmsh).

By fitting the compression and swelling of pasta disks and the swelling of PDMS disks, the key material properties of the pasta and PDMS were obtained and are shown in Table 45B. The Flory-Huggins interaction parameter χ are taken from literature. See S. A. Chester, C. V. Di Leo, L. Anand,Int. J. Solids Struct.52, 1-18 (2015) and R. G. M. van der Sman, M. B. J. Meinders,Soft Matter.7, 429-442 (2011). It should be noted that χ for pasta is known to be dependent on the water concentration. Here, a typical value (χ) representing the swelling nature of pasta was chosen. To normalize the disk swelling data inFIG.43A, the time was divided by its diffusion characteristic time scale, τ, given by
τ=H2/D,(Eqt. 7)

where H is the thickness of the disk and D is the diffusion coefficient. For the pasta (H=2 mm) and PDMS (H=0.9 mm) disks, the calculated diffusion characteristic time scale are τpasta=2000 s and τPDMS=405 s.

With this simplified model, the morphing process of various structures was simulated and is highlighted inFIGS.31,42and43and found to be in good agreement with experiments using components that were designed, fabricated and tested.

Self-Folding Materials and Method for Making the Same: As described previously, this application encompasses self-folding non-food materials and methods of making the same100. The method100, design tool200and digital fabrication process300described above and below offer three possible embodiments of ways to make self-folding materials60. The various self-folding materials60can be made from an initially flat piece of material or the materials can be made from gels or liquids that are cast or molded into an initial shape26. In all instances, the material of an initial shape26and initial size28has a top surface22and a bottom surface24, which can be interchangeable as discussed in relation to the shape-changing dough. Again, the initial material70is designed to have a predetermined initial shape26and a predetermined initial size28. Additionally, at least one surface22,24of the material is grooved with at least one set of parallel grooves30running perpendicular to a predetermined bending direction40on it. Optionally, a second or bottom surface24of the initial material70can be grooved with at least one set of parallel grooves30running perpendicular to a predetermined bending direction40on it. For any set or sets of parallel grooves30on either the top surface22or the bottom surface24, the grooves can cover all or part of the top surface22and/or bottom surface24. Finally, the at least one set of parallel grooves30has a groove depth32, a groove spacing34and a groove shape chosen to achieve a predetermined bending angle42or a predetermined final shape44. This grooved dough20is then exposed to a stimuli50, such as hydration52, dehydration54, a solvent, or other appropriate stimuli50, which causes the initial piece of material70to change shape or bend. This initial material70can be made of one homogeneous material or it can be made of more than one layers29of different materials having different compositions and/or different thicknesses. The optional use of different layers29of materials having different thicknesses, compositions, and/or different ratios of thicknesses impacts the bending angle42of the material and these factors can be varied to achieve predetermined bending angle42and/or predetermined final shapes44. Alternatively, any one of these factors can be varied to achieve a predetermined bending angle42and/or predetermined final shapes44.

The initial materials70used to create self-folding materials60need to have the characteristics of being able swell or deswell when exposed to a stimuli50. It will be obvious to those skilled in the art that such materials include but are not limited to silicones, silicone rubber, silicone elastomers and hydrogels. Also, it will be obvious to one skilled in the art that these methods100and various embodiments of this invention can be application to a wide type of materials and compounds that have similar attributes to those listed herein.

Computational Design Tool200: One embodiment of the present invention includes using the computational design tool200described above to produce self-folding materials60as well. Instead of integrating cooking guides, the computational design tool200will integrate the parameters for preparing the grooved initial material and for exposing120that material to a stimuli50to help users easily design and simulate shape-changing materials60(broadly shown inFIGS.7A through7Eand diagramed inFIGS.38,39and40). More specifically, the design tool200implements the present invention's method100with a multi-step design flow, which steps can be displayed and controlled by an optional user interface. One embodiment of the computational design tool200has a 3D shape library210comprised of at least one 3D shape for self-folding materials60, from which library210the self-folding material's shape and/or the predetermined final shape44is defined or selected (FIGS.7A,39and40). This computational design tool200also has database212containing information on grooves and grooving parameters (and optionally suggested stimuli50) that correlates to each of the at least one 3D shapes and initial material60for self-folding materials60(FIGS.38and40). From this database212, the area of grooves and the grooving110parameters are set220(FIGS.7B and40). This embodiment of the computational design tool200also has a code generator214to produce code for production of the 3D self-folding materials60. G-code or other similar code is generated240by a code generator214to control the machine(s) (FIGS.7D,38,39and40).

Digital Fabrication Process: The present invention also encompasses use of the shape-changing food digital fabrication process300, with minor modifications, for the creation of self-folding materials60. Similar to the method100and computational design tool200, the digital fabrication process300includes the steps of: (i) creating the initial material70; and (ii) sheeting, molding, stamping, casting, and/or forming the initial material70into an initial shape26with surface grooves30. This second step can entail one or more sub-steps depending upon the material being used and can combine the cutting316and grooving110steps for shape-changing foods into one step where a technique like molding is used. These various steps and sub-steps are described in more detail in the sections of this application dealing with food and can be seen onFIGS.39and41.

Another embodiment of the present invention's digital fabrication process300for creating self-folding materials60has the following steps. This embodiment comprising the steps of: (i) composing, making, or selecting an initial material70; (ii) forming the initial material70to a predetermined thickness as measured between a first surface22of the initial material70and a second surface24of the initial material70, a predetermined initial shape26and a predetermined initial size28; and (iii) grooving110the initial material70on at least one of the first surface and the second surface22,24to cause the initial material70to bend when the initial material70is exposed to a stimuli50.

The previous explanation describes example embodiments in which the present invention may be practiced. This invention, however, may be embodied in many different ways, and the description provided herein should not be construed as limiting in any way. Among other things, the following invention may be embodied as methods or devices. The detailed descriptions of the various embodiments of the present invention should not be taken in a limiting sense.