CN101533530A - Method for preparing 3D ornament based on poor-chaos graph - Google Patents

Abstract

The invention discloses a method for preparing the 3D ornament based on the poor-chaos graph, including the steps: (1) generating the poor-chaos graph; (2) treating poor-chaos graph; (3) generating 3D point cloud; (4) performing the grid reconstruction for the 3D point cloud to form the grid curved surface; (5) closing the grid curved surface to form the 3D closed curved surface; (6) converting the 3D closed curved surface into a file capable of be identified by a rapid moulding device, inputting the file to the rapid moulding device for forming and completing the preparation of the3D ornament. The invention has outstanding characteristics: the 2D poor-chaos graph adopts the curved surface forming way to perform the 3D closed curved surface, the data is transmitted to the rapid moulding device for forming, the designed speed is rapid, the ornament has high precision and changeful graph, thus effectively expanding the design visual field and forming rich and novel ornament.

Description

3D ornaments preparation method based on poor-chaos graph

[affiliated technical field]

The present invention relates to a kind of ornaments preparation method, relate in particular to a kind of 3D ornaments preparation method based on poor-chaos graph.

[background technology]

Traditional ornaments design is quite complicated, relies on designer's inspiration to create hand-designed fully.Simultaneously, also need to repair design original text, the design of version type etc. through computing machine.Design comparatively singlely, and the time spent is very long.In conjunction with casting technique, the design of ornaments is at present produced and mainly is divided into three major types.

(1) accurate complicated high-end ornaments: utilization Freehandhand-drawing design original text or combined type design (combined type design " refer to combining of hand-designed and software design; with hand-designed original text input computing machine; will knock off by computer software and to design original text and be designed to the Electronic Design original text, change into file that rapid forming equipment can discern at last and import rapid forming equipment and get final product.), adopt the making of traditional handicrafts such as engraving, filigree, string treasured.

(2) product of low side: mainly use the combined type design, adopt methods such as the accurate casting process of modernization, machining to realize.

(3) new technique: the manufacturing that is produced as ornaments of CAD/CAM technology and rapid shaping technique provides new possibility.Designer and craftsman have broken away from check and correction process very long from the two dimensional image to the 3 D stereo, directly carry out pattern identification and making by rapidform machine, and finished product is comparatively exquisite.But the original shape of design original text still is the manuscript of hand-designed.

, the propensity to consume day by day polynary modern society quick in economic development, ornaments are exposing some deficiency aspect the design production:

(1) design process is quite numerous and diverse.No matter be the design or the combined type design of pure Freehandhand-drawing, be subjected to artificial restriction, and design (design for combined type slowly, same design original text needs twice design operation, design slower), the production cycle is long, is difficult to satisfy the consumption market of differentiation, diversification.

(2) design is subjected to the restriction of human brain, is difficult to create the design that makes new advances in the short time.

(3) the ornaments shipment speed of traditional handicraft manufacturing is not directly proportional with fineness, influences the quality of product.

[summary of the invention]

The object of the present invention is to provide a kind of 3D ornaments preparation method based on poor-chaos graph, 2D poor-chaos graph utilization surface modeling means are finished the design of 3D ornaments, design rate is fast, prepared ornaments precision height, and with countless changes, the attractive in appearance novelty of the face shaping that can also make ornaments, break through people's inspiration restriction, and the moulding controllability is strong, solves the above-mentioned defective that prior art exists.

The present invention solves the technical scheme that the prior art problem adopted: based on the 3D ornaments preparation method of poor-chaos graph, its step comprises: (one), generate poor-chaos graph; (2), handle poor-chaos graph, it is characterized in that: (three), the poor-chaos graph generation 3D point cloud that will handle; (4), 3D point cloud is carried out grid reconstruction and form grid surface; (5), the grid surface sealing is formed the 3D closed surface; (6), the 3D closed surface is changed into the file that rapid forming equipment can be discerned, this document is imported rapid forming equipment form processing, finish the preparation of 3D ornaments.The present invention mainly develops the poor-chaos graph based on even random networks and quasi-regular pattern theory.Evenly random networks is reversed to shine upon to satisfy under the certain condition by resonance and is produced.Quasi-regular pattern theory then is the characteristics according to nonlinear kinetics system under the weak chaos condition, is undertaken by aiming at symmetrical random networks that level and smooth operation forms.Owing to the present invention seeks to the 2D poor-chaos graph is formed the moulding of 3D closed surface, at last the data delivery of 3D closed surface is processed to rapid forming equipment, can obtain the 3D ornaments.High energy particle movement locus in the former not visible weak chaotic dynamics field is converted into aesthstic information, carry out inexhaustible graphic change and conversion according to the nonlinear kinetics principle, simultaneously, can carry out optionally " sketch the contours on the border " (promptly intercepting the part on the poor-chaos graph) to the figure that generates as required, the degree of freedom of outward appearance control is very big.Becoming matiere, design the visual field thereby expanded ornaments effectively, the ornaments outward appearance of formation is abundant novel, thereby has higher commercial application value.By computing machine the 2D figure is converted into the 3D model, design accuracy quality higher, that therefore make is better, can satisfy the market trend of diversification, personalization, fashion-orientation preferably.

As the further of technique scheme improved and replenish, the present invention adopts following technical measures: the step of described processing poor-chaos graph comprises: cutting poor-chaos graph zone; The step that the described poor-chaos graph that will handle generates 3D point cloud is: the poor-chaos graph to cutting carries out gradation conversion, become 3D point cloud by the 2D image transitions, its field of definition is the clipping region of 2D image, and its height of selecting is the function about the gray-scale value of 2D image slices vegetarian refreshments; Then, the 3D point cloud that generates is carried out denoising.Planar graph is converted into 3D point cloud.

Describedly 3D point cloud is carried out the step that grid reconstruction forms grid surface be: at first 3D point cloud is projected on the X-Y plane, form projection domain point cloud, and according to its distribution, to the X-Y plane zone that comprises projection domain point cloud by the horizontal and vertical quadrilateral mesh that is divided into, then to dropping on each quadrilateral in the projection domain, selecting wherein, a limit connection if having only three points to drop in the projection domain in the quadrilateral, then directly connects this 3 point to carry out triangulation; To finish the projection domain grid behind the triangulation at last, and keep topological relation and former 3D point cloud coordinate figure constant, shine upon back 3d space, thus formation 3D grid surface.3D point cloud is converted into the 3D curved surface.

Described step with 3D point cloud surface reconstruction formation grid surface also comprises grid surface optimization, and the step of grid surface optimization comprises: a) triangle is carried out interactive operation, reduces long and narrow triangle; B) deletion is long and narrow or to the little triangle of model influence, simplifies grid.

Described step with 3D point cloud surface reconstruction formation grid surface also comprises the grid fairing, reduces noise.

Described step with grid surface sealing formation 3D closed surface is: at first search out all frontier points of grid surface outmost turns by the point and the order of connection of putting, then toward Z axle negative direction stretch border point, produce a circle contour point, the length that stretches is more than or equal to zero, and carries out trigonometric ratio with the frontier point of former grid surface outmost turns; Construct the base curved surface then.

When structure base curved surface,, then determine the base central point and carry out trigonometric ratio to get final product if the base curved surface is a plane;

When structure base curved surface,, the geometry of former grid surface and topology information are carried out symmetrical mapping obtain if base is the plane of symmetry;

When structure base curved surface, if the bottom surface is the curved surface different with former curved surface, then can generate this surface points cloud earlier, carry out splicing with former curved surface behind the trigonometric ratio.

The present invention has outstanding substantive distinguishing features: 1, the 3D closed surface that the intact 3D ornaments of 2D poor-chaos graph utilization surface modeling means are designed, and data delivery processed to rapid forming equipment, design rate is fast, prepared ornaments precision height can satisfy the market trend of diversification, personalization, fashion-orientation preferably. 2, with countless changes, the attractive in appearance novelty of poor-chaos graph, can make the ornaments design break through people's inspiration restriction, former not visible weak chaotic dynamics field Rigen is carried out inexhaustible graphic change, and aesthstic information translation according to the nonlinear kinetics principle, expanded the ornaments design visual field effectively, the ornaments outward appearance of formation is abundant novel; 3, also can carry out optionally " sketch the contours on the border " (promptly intercepting the part on the poor-chaos graph) to the figure that generates as required, the degree of freedom of outward appearance control is very big.

[embodiment]

The present invention is further illustrated below in conjunction with the drawings and specific embodiments.

Embodiment: based on the 3D ornaments preparation method of poor-chaos graph, its step comprises: (one), generation poor-chaos graph; (2), handle poor-chaos graph, (three), the poor-chaos graph generation 3D point cloud that will handle; (4), 3D point cloud is carried out grid reconstruction and form grid surface; (5), the grid surface sealing is formed the 3D closed surface; (6), the 3D closed surface is changed into the file that rapid forming equipment can be discerned, this document is imported rapid forming equipment form processing, finish the preparation of 3D ornaments.The present invention mainly develops the poor-chaos graph based on even random networks and quasi-regular pattern theory.Evenly random networks is reversed to shine upon to satisfy under the certain condition by resonance and is produced.Resonance reverse and be mapped in (u when v) satisfying resonant condition on the plane, is an integer as q, then is called the q rank and resonates and reverse mapping when q subresonance condition is set up:

${\hat{M}}_q=\left\{\begin{array}{c}\stackrel{\‾}{u}=(u+K\sin v)\cos \left(\frac{2\mathrm{\π}}{q}\right)+v\sin \left(\frac{2\mathrm{\π}}{q}\right)\\ \stackrel{\‾}{v}=-(u+K\sin v)\sin \left(\frac{2\mathrm{\π}}{q}\right)+v\cos \left(\frac{2\mathrm{\π}}{q}\right)\end{array}\right.---\left(1\right)$

Studies show that, as q 2 the time, resonance is reversed mapping corresponding to amassing hamiltonian system, might produce chaos.Following q value set { q _c}={ 1,2,3,4,6, } corresponding to the infinitely great periodically evenly random networks on the phase plane; And work as $q\∉\left\{q_c\right\}$ The time, q=5 for example, 7, during 8..., then can form exquisiteness and complicated net quasi-periodicity with various symmetrical beauties.Even random networks pattern edge exquisiteness, clear, the color change fluctuation ratio in the same field is bigger, therefore needs through special processings such as filtering the reduction heterochromia.The method that the present invention takes is the brightness value of being represented by rgb value by suitable control, and the height value after the conversion is limited in the suitable scope.

Quasi-regular pattern theory then is the characteristics according to nonlinear kinetics system under the weak chaos condition, carries out level and smooth operation by aiming at symmetrical random networks, promptly by the Hamiltonian conversion: $H_q(\mathrm{\μ},\mathrm{\γ},t)=H_q^0(\mathrm{\μ},\mathrm{\γ})$ Obtain.Specifically, for the resonance mapping of q rank

The Hamiltonian of dynamical system:

$H_q=(\mathrm{\π}/q)(u^2+v^2)-K\sin v\underset{n=-\∞}{\overset{\∞}{\mathrm{\Σ}}}\mathrm{\δ}(t-n)---\left(2\right)$

Determined q accurate symmetric net, carry out smoothing by two steps and handle:

The first step, transforming to one is in the rotational coordinates of v=1/q rotation with the frequency;

Second step, the time to be asked on average, the Hamiltonian that is obtained is

That is:

$H_q^0=\underset{j=1}{\overset{q}{\mathrm{\Σ}}}\cos (u\cos \frac{2\mathrm{\πj}}{q}+v\sin \frac{2\mathrm{\πj}}{q})---\left(3\right)$

Can face

Level line $H_q^{\left(0\right)}(u,v)=E^0$ Provide the different shape of system and the closed invariant curve family of size.For quasi-regular pattern theory, owing to it is undertaken smoothly obtaining by even random networks, its figure color change itself seamlessly transits, and these characteristics just make quasi-regular pattern theory be suitable for being converted into the 3D moulding most, can be directly used in conversion.

Rapid forming equipment adopts HRPL series (SLA) photocureable rapid shaping system, be provided with ornaments Processing CAM software in it, for with the CAM software interface, the 3D closed surface is changed into the file that rapid forming equipment can be discerned, and the form of this document is STL (the triangle grid model data of record ornaments).The file layout of STL has ASCII character and two kinds of output forms of binary code, can select one.The STL formatted file provides the geological information of all triangular plates that constitute solid object surface one by one; The geological information of each triangular plate comprises method vector and 3 apex coordinates on plane, triangle place, the summit put in order and method must be followed right-hand rule between vowing.Stl file is imported HRPL series (SLA) photocureable rapid shaping system, carry out the shaping processing of ornaments, material processed can be selected plastics and photosensitive resin etc.

The step of handling poor-chaos graph comprises: cutting poor-chaos graph zone; The step that the described poor-chaos graph that will handle generates 3D point cloud is: the poor-chaos graph to cutting carries out gradation conversion, become 3D point cloud by the 2D image transitions, its field of definition is the clipping region of 2D image, and its height of selecting is the function about the gray-scale value of 2D image slices vegetarian refreshments; Then, the 3D point cloud that generates is carried out denoising.At first the figure that step () is generated carries out regional cutting to obtain the face shaping of required design ornaments.Can there be rectangle, (ellipse) circle, polygon, Bezier closed curve etc. in the zone of cutting.Use the mouse swap operation, cutting is sketched the contours on the border of " interested " graphics field, to obtain needed image.Subsequently, adopt experimental formula: grey=0.299R+0.587G+0.114B, the image of institute clipping region is carried out gradation conversion.

3D point cloud by the 2D image transitions, its field of definition is the zone at image slices vegetarian refreshments place, it highly then directly is decided by the gray-scale value of image, that is has determined funtcional relationship a: hight=h (grey) between the height value of the gray-scale value of 2D image and 3D point cloud.For reaching consistance on the level and smooth meaning of 2D image and 3D point cloud and the control of being convenient to the poor-chaos graph correlation parameter, this function must possess increasing or decreasing.Generally can choose linear function according to the scope of get height, i.e. hight=agrey+b, (255 〉=grey 〉=0).In the present invention, a=1, b=0,10≤grey≤100.

Because image function disperses, the figure after so transforming just is converted into the 3D point cloud model.

The 2D image some noises may occur after being converted into 3D point cloud.At this moment, can use various filtering methods to carry out noise reduction process, the automatic filter technology that for example can adopt formula to differentiate: standard Gauss, N point average filter, medium filtering etc., to realizing the level and smooth filtering of noise spot in the cloud neighborhood.The weight of gaussian filtering in specified domain is Gaussian distribution, and its average effect is less, so can keep the pattern of legacy data preferably when filtering; The value of average filter sampled point is got the assembly average of each data point in the filter window; The value of medium filtering sampled point is got the statistics intermediate value of each data point in the filter window, and the effect of this filtering elimination burr is better.

The step of 3D point cloud being carried out grid reconstruction formation grid surface is: at first 3D point cloud is projected on the X-Y plane, form projection domain point cloud, and according to its distribution, to the X-Y plane zone that comprises projection domain point cloud by the horizontal and vertical quadrilateral mesh that is divided into, then to dropping on each quadrilateral in the projection domain, selecting wherein, a limit connection if having only three points to drop in the projection domain in the quadrilateral, then directly connects this 3 point to carry out triangulation; To finish the projection domain grid behind the triangulation at last, and keep topological relation and former 3D point cloud coordinate figure constant, shine upon back 3d space, thus formation 3D grid surface.3D point cloud is the set of spatial point at random.By dispersion point cloud reconstruct interpolation curved surface, choosing of its method is to influence a moulding shape and a very important step of characteristics.In conjunction with the needs of producing reality, and the simplicity of considering triangle gridding construction 3D curved surface, reconstruct surface methodology---triangulation method commonly used at present selected for use.Because the cloud data that generates, point on its X-Y plane is unique corresponding to a Z value, therefore, the triangulation method just can adopt the plane domain sciagraphy, promptly on the X-Y plane territory, carry out earlier triangulation, and utilize optimization criterions such as sphere criterion or polyhedron volume maximal criterion to select those points are coupled together, then the subdivision result is projected to 3d space.

After large-scale cloud data carried out triangulation, not only data volume seemed too fat to move, and occurs some long and narrow triangles unavoidably, made the not enough fairing that seems of reconstruct curved surface, still needs grid surface is carried out further optimization process.

The step that 3D point cloud surface reconstruction is formed grid surface also comprises grid surface optimization, and the step of grid surface optimization comprises: a) triangle is carried out interactive operation, reduces long and narrow triangle; B) deletion is long and narrow or to the little triangle of model influence, simplifies grid.Adopt the geometric element elimination method---the edge contraction shortcut calculation of estimating based on second order error.This basic idea is: at first calculate an error matrix for each summit in the original mesh, and calculate the position on the new summit of the cost of edge contraction in the triangular mesh and generation according to error matrix, the size of paying a price according to folded edge is carried out folding operation successively according to ascending order then, and the error matrix of the folding new point that generates is the error matrix sum on two summits of folded edge.Can realize that grid optimization can keep model accuracy again, is controlled at the simplification rate in 10% among the present invention.

The step that 3D point cloud surface reconstruction is formed grid surface also comprises the grid fairing, reduces noise.

Laplce's fairing method is a kind of grid fairing algorithm.It adjusts grid by each summit Laplace operator of definition of grid model being determined an adjustment direction and displacement.Discrete Laplace operator can be described with following formula: $L\left(i\right)=\frac{1}{N}\underset{v_i\mathrm{link}\left(i\right)}{\mathrm{\Σ}}(v_j-v_i),$ Be adjusted into after each summit process Laplace operator effect of grid surface: $v_i^{\′}=v_i+\mathrm{\μL}\left(i\right).$

Laplace operator fairing technology is the bigger grid surface of deal with data amount effectively, but it can excessive fairing sharp features and high frequency noise.For model is carried out better fairing processing, also can adopt other fairing algorithm: for example improve Laplce's algorithm (HC algorithm), improved weighted method is to median filtering method, mean curvature flow ^[29], bidirectional filtering method etc.The fairing effect of every kind of algorithm is not quite similar, and for obtaining different modelling effects, can use different algorithms to carry out fairing processing.

The step that the grid surface sealing is formed the 3D closed surface is: at first search out all frontier points of grid surface outmost turns by the point and the order of connection of putting, then toward Z axle negative direction stretch border point, produce a circle contour point, the length that stretches is more than or equal to zero, and carries out trigonometric ratio with the frontier point of former grid surface outmost turns; Construct the base curved surface then.The actual production processing request model of ornaments is entities, i.e. occluding surface, and the model that above step generates only is an open surface, therefore also need be translated into closed body.

When structure base curved surface,, then determine the base central point and carry out trigonometric ratio to get final product if the base curved surface is a plane;

When structure base curved surface,, the geometry of former grid surface and topology information are carried out symmetrical mapping obtain if base is the plane of symmetry;

When structure base curved surface, if the bottom surface is the curved surface different with former curved surface, then can generate this surface points cloud earlier, carry out splicing with former curved surface behind the trigonometric ratio.

Claims (10)

1. based on the 3D ornaments preparation method of poor-chaos graph, its step comprises: (one), generation poor-chaos graph; (2), handle poor-chaos graph, it is characterized in that: (three), the poor-chaos graph generation 3D point cloud that will handle; (4), 3D point cloud is carried out grid reconstruction and form grid surface; (5), the grid surface sealing is formed the 3D closed surface; (6), the 3D closed surface is changed into the file that quickly shaping device can be discerned, this document is imported quickly shaping device form processing, finish the preparation of 3D ornaments.

2. the 3D ornaments preparation method based on poor-chaos graph according to claim 1 is characterized in that the step of described processing poor-chaos graph comprises: cutting poor-chaos graph zone; The step that the described poor-chaos graph that will handle generates 3D point cloud is: the poor-chaos graph to cutting carries out gradation conversion, become 3D point cloud by the 2D image transitions, its field of definition is the clipping region of 2D image, and its height of selecting is the function about the gray-scale value of 2D image slices vegetarian refreshments; Then, the 3D point cloud that generates is carried out denoising.

3. the 3D ornaments preparation method based on poor-chaos graph according to claim 1 and 2, it is characterized in that describedly 3D point cloud is carried out the step that grid reconstruction forms grid surface being: at first 3D point cloud is projected on the X-Y plane, form projection domain point cloud, and according to its distribution, to the X-Y plane zone that comprises projection domain point cloud by the horizontal and vertical quadrilateral mesh that is divided into, then to dropping on each quadrilateral in the projection domain, selecting wherein, a limit connects to carry out triangulation, if have only three points to drop in the projection domain in the quadrilateral, then directly connect this 3 point; To finish the projection domain grid behind the triangulation at last, and keep topological relation and former 3D point cloud coordinate figure constant, shine upon back 3d space, thus formation 3D grid surface.

4. the 3D ornaments preparation method based on poor-chaos graph according to claim 3, it is characterized in that described step with 3D point cloud surface reconstruction formation grid surface also comprises grid surface optimization, the step of grid surface optimization comprises: a) triangle is carried out interactive operation, reduces long and narrow triangle; B) deletion is long and narrow or to the little triangle of model influence, simplifies grid.

5. the 3D ornaments preparation method based on poor-chaos graph according to claim 4 is characterized in that described step with 3D point cloud surface reconstruction formation grid surface also comprises the grid fairing, reduces noise.

6. the 3D ornaments preparation method based on poor-chaos graph according to claim 1 and 2, it is characterized in that described step with grid surface sealing formation 3D closed surface is: at first search out all frontier points of grid surface outmost turns by the point and the order of connection of putting, then toward Z axle negative direction stretch border point, produce a circle contour point, the length that stretches is more than or equal to zero, and carries out trigonometric ratio with the frontier point of former grid surface outmost turns; Construct the base curved surface then.

7. the 3D ornaments preparation method based on poor-chaos graph according to claim 5, it is characterized in that described step with grid surface sealing formation 3D closed surface is: at first search out all frontier points of grid surface outmost turns by the point and the order of connection of putting, then toward Z axle negative direction stretch border point, produce a circle contour point, the length that stretches is more than or equal to zero, and carries out trigonometric ratio with the frontier point of former grid surface outmost turns; Construct the base curved surface then.

8. the 3D ornaments preparation method based on poor-chaos graph according to claim 7 is characterized in that when structure base curved surface, if the base curved surface is a plane, then determines the base central point and carry out trigonometric ratio to get final product.

9. the 3D ornaments preparation method based on poor-chaos graph according to claim 7 is characterized in that when structure base curved surface, if base is the plane of symmetry, the geometry of former grid surface and topology information is carried out symmetrical mapping obtain.

10. the 3D ornaments preparation method based on poor-chaos graph according to claim 7 is characterized in that if the bottom surface is the curved surface different with former curved surface, then can generating this surface points cloud earlier when structure base curved surface, carries out splicing with former curved surface behind the trigonometric ratio.