Methods for fabrication of articles from three-dimensional models
Methods for fabrication of articles, in particular knitted articles, using computer-controlled machines. A 3D model of the article is characterized by a 3D polygonal mesh defining a surface of the 3D model. A streamline is drawn on the 3D model, and used to define a set of isolines over the surface described by the 3D polygonal mesh. The isolines are quantized into equidistant points along their respective lengths and a cut line traversing each of the isolines is defined. Courses are defined by connecting quantization points of the isolines based on knitting rules to produce a 2D knitting map containing apexes. Apex attraction may be performed on a first portion of the 2D knitting map by decreasing a spatial distance between respective ones of the apexes. The 2D knitting map is subsequently converted to knitting instructions for a computer-controlled knitting machine.
1. A method, comprising:
for a three-dimensional (3D) model defined in a 3D space, defining a streamline on said 3D model, said streamline being a line drawn over a surface of the 3D model;
using the streamline as an origin, defining a set of isolines over the surface of the 3D model;
for each of the isolines, determining quantization points along a length of each isoline;
generating courses by connecting the quantization points of the isolines based on knitting rules to produce a two-dimensional (2D) knitting map containing apexes which terminate an end of respective pairs of the courses, the 2D knitting map specifying locations of stitches for a knitted article, wherein all of the courses of the 2D knitting map extend along straight lines that are arranged parallel to one another;
for a portion of the 2D knitting map, decreasing or increasing a spatial distance between respective ones of the apexes within the portion of the 2D knitting map, wherein an amount of the spatial distance decreased or increased between respective ones of the apexes of the portion of the 2D knitting map is based on an input value received from a user;
converting the 2D knitting map to knitting instructions for a computer-controlled flatbed knitting machine; and
transmitting said knitting instructions to said computer-controlled flatbed knitting machine so as to produce the knitted article in accordance with the knitting instructions.
2. The method of claim 1 , further comprising:
prior to the converting of the 2D knitting map to the knitting instructions, presenting the 2D knitting map for review and edit by the user; and
updating the 2D knitting map according to revisions made by the user.
3. The method of claim 2 , further comprising, prior to the converting of the 2D knitting map to the knitting instructions, defining an updated 3D model based on an updated 2D knitting map reflecting said revisions made by said user, and repeating the steps of defining the streamline, defining the set of isolines, quantizing the isolines, generating the courses, decreasing or increasing the spatial distance between respective ones of the apexes within the portion of the 2D knitting map, and producing a further updated 2D knitting map using the updated 3D model.
4. The method of claim 1 , further comprising:
prior to the converting of the 2D knitting map to the knitting instructions, defining an updated 3D model based on the 2D knitting map; and
updating the 2D knitting map using the updated 3D model.
5. The method of claim 1 , wherein the 3D model is one of: selected from a library, produced from imaging of a physical article, produced by the user algorithmically, or produced by the user manually.
6. The method of claim 1 , wherein the isolines are determined according to a heat method for computing geodesic distances.
7. The method of claim 1 , further comprising defining a cut line on the surface, said cut line representing a seam to be sewn in the knitted article knitted by the computer-controlled flatbed knitting machine and traversing each of the isolines, but only once per respective isoline.
8. The method of claim 7 , wherein the cut line is determined by:
ordering the isolines and indexing the quantization points into groups matching the isolines;
selecting a non-branching one of the isolines as a current isoline starting point and selecting one of the quantization points that lies along the current isoline as a current point in the cut line;
updating the cut line by, for each isoline adjacent to the current isoline, determining a closest quantization point in the adjacent isoline to the current point, and drawing the cut line to connect the current point to the closest quantization point in the adjacent isoline; and
repeating the process of updating the cut line to connect subsequent closest points of subsequent adjacent isolines, treating immediately preceding adjacent isolines as new current isolines and immediately preceding closest quantization points of those isolines now connected by the cut line as current points, until every isoline of the 3D model is traversed.
9. The method of claim 1 , further comprising:
receiving a texture map representing a design, logo, pattern, or other features to be produced as part of the completed knitted article knitted by the computer-controlled flatbed knitting machine, wherein the texture map specifies one or more of texture or color on the surface of the 3D model;
applying the texture map to the 3D model; and
immediately after the 2D knitting map has been produced, transferring information represented in the texture map from the 3D model to the 2D knitting map.
10. The method of claim 9 , wherein the texture map specifies one or more of texture or color on the surface of the 3D model.