CN102486641B - Artificial-teeth processing route generating method - Google Patents

Artificial-teeth processing route generating method Download PDF

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CN102486641B
CN102486641B CN201010572599.8A CN201010572599A CN102486641B CN 102486641 B CN102486641 B CN 102486641B CN 201010572599 A CN201010572599 A CN 201010572599A CN 102486641 B CN102486641 B CN 102486641B
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cutter
processing
contour curve
artificial
track
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CN102486641A (en
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刘伟军
张鸣
李论
卞宏友
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Shenyang Institute of Automation of CAS
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Abstract

The invention relates to an artificial-teeth processing route generating method, which belongs to the numeric-control processing technical field, and comprises the following steps that: a cutter track for roughly processing artificial teeth is firstly generated, then a cutter track for precisely processing the artificial teeth is generated, the rough processing of the cutter track is divided into two steps: generation of a Z-direction rough processing route and generation of a negative Z-direction rough processing route, and the precise processing of the cutter track is divided into two steps: generation of Z-direction precise processing route and generation of a negative Z-direction precise processing route. The generation of the rough processing route comprises the following steps that: (1) determining a material removal area; (2) acquiring an intersection outline curve set; (3) processing the intersection outline curve set; (4) generating a processing area; (5) filling routes; and (6) joining the routes. The generation of the precise processing route comprises the following steps that: (1) determining a material removal area; (2) acquiring an intersection outline curve set; (3) processing the intersection outline curve set; (4) generating a processing area; (5) filling routes; and (6) joining the routes. Due to the adoption of the artificial-teeth processing route generating method, the route planning problem of an artificial-teeth numeric-control processing cutter can be effectively solved, and the efficiency problem and the quality stability problem for manually preparing artificial teeth can be solved.

Description

Artificial-teeth processing route generating method
Technical field
The invention belongs to CNC processing technology field, be specifically related to a kind of artificial-teeth processing route generating method
Background technology
The preparation of tooth mould generally adopts reverse mould method, and after obtaining the gypsum former of root of the tooth, the model of tooth and jaw portion just obtains.According to gypsum reverse mould, can produce a formpiston, this formpiston has reflected patient's oral condition.After obtaining formpiston, adopt the method for reconstructing based on a cloud or image, the digital model of artificial tooth and jaw portion is described out with grid or spline surface.In reference, coincide relation and facing on the basis of tooth information of lower jaw, by the local Transform Type design of CAD, is suitable for the artificial tooth digital model of processing.
The patent of invention that the patent No. is 00816582.3 provides a kind of lathe for dentistry prosthesis making pedestal structure, wherein discuss a kind of artificial tooth and be contoured method, the method needs DENSP with the manual basic mode of preparing artificial tooth of paraffin or plastics, then adopts lathe described in this patent to be contoured.What this job operation adopted is the mode that ratio copies, and does not relate to the trajectory planning problem of artificial tooth processing.And because design and the preparation of basic mode adopts pure manual mode, automaticity is not high, and preparation efficiency is relatively low, and artificial tooth quality depends on DENSP's level, and artificial tooth difficult quality is controlled.US Patent No., A5184306 discloses a kind of made with high precision method of single-piece complex object, and the method can be used for biological bone processing.The method is by search the model matching with realistic model in model bank, thereby finds the standard cutter rail that is applicable to realistic model, and then obtains actual processing cutter rail by revising the mode of cutter rail parameter value.But the method without proper notice are for the generation method of the standard cutter rail of artificial tooth processing process.
Summary of the invention
For the technical matters of above-mentioned existence, the invention provides a kind of artificial-teeth processing route generating method.
The technical solution adopted for the present invention to solve the technical problems is:
Artificial-teeth processing route generating method of the present invention, first generate for the rough machined cutter rail of artificial tooth, regeneration is for the accurately machined cutter rail of artificial tooth, the generation of described roughing cutter rail be divided into that Z-direction roughing track generates and-Z-direction roughing track generates two steps, the generation of finishing cutter rail be divided into that Z-direction finishing track generates and-Z-direction finishing track generates two steps.
Roughing orbit generation method step of the present invention is as follows: 1. determine material removal area; 2. obtain to cut and hand over contour curve collection; 3. process to cut and hand over contour curve collection; 4. generate machining area; 5. track is filled; 6. track connects.
Described definite material removal area step is as follows: first adopt artificial tooth 2D to limit box B 2Dblank Γ carries out Boolean operations and show that 3D limits box B 3D, use B 3Dboolean deducts artificial tooth digital model M, obtains material removal area γ total; Use γ totalboolean deducts artificial tooth and connects bearing rib Ψ, obtains Z-direction material removal area γ zwith-Z-direction material removal area γ -z:
γ total=(B 2D∩T)-M
z,γ -z}=γ total
Wherein: when determine connecting the Z height of bearing rib Ψ, first determine the silhouette of denture model, using the minimum Z value of silhouette as the Z height value of connection bearing rib.
Describedly obtain that cut to hand over a contour curve collection step be to adopt equally spaced planar set and the Z-direction material removal area γ vertical with Z axis zask intersection, draw intersection contour curve collection.
Described processing cuts hands over contour curve collection step as follows: the non-outermost contour curve in the slicing layer between the minimum and maximum Z value of silhouettes, with largest contours line, replace the contour curve obtaining.
Described finishing orbit generation method step is as follows: 1. determine finishing region; 2. obtain to cut and hand over contour curve collection; 3. obtain initial cutter-contact point collection; 4. generate initial cutter location; 5. interference checking and processing; 6. track connects.
Described definite finishing machining area: be that artificial tooth is cut apart along its silhouette, obtain Z-direction and-Z-direction cuts apart curved surface, Z-direction machining area is Z-direction and cuts apart curved surface, and actual-Z-direction finishing region is cut apart curved surface for-Z-direction and removed the region that connects bearing rib gained.
Describedly obtain that cut to hand over a contour curve collection step be to adopt the planar set that is parallel to Z axis or becomes 30-60 angle with Z axis, intercept initial profile curve set.
Described interference checking and disposal route are as follows: calculate initial cutter location p to the bee-line d of denture model, if bee-line is less than ball cutter radius r, this initial cutter location interferes, disposal route while interfering is: when obtaining bee-line, obtain on tooth mould and initial cutter location have bee-line a bit, calculate the direction of normal n of the curved surface at this some place, new adjustment position p *adopt following formula to adjust: to make p *for p, repeat said process, until d equals ball cutter radius r:
r p * = r p + | r - d | &CenterDot; n ( r < d ) r p - | r - d | &CenterDot; n ( r > d )
Wherein: r is ball cutter radius, d is that initial cutter location p is to the bee-line of denture model, r pfor vector radius,
Figure BDA0000035966980000032
for the new vector radius of adjusting position, n is direction of normal.
It is described that to obtain initial cutter-contact point collection be to adopt the method for straight line or two circular fittings to obtain the cutter-contact point collection after discrete; Obtaining initial cutter location is the method vector that obtains curved surface place, cutter-contact point place, and cutter-contact point, along a ball cutter radius of the outside biasing of method direction vector, is obtained to initial cutter location.
The invention has the beneficial effects as follows:
1. adopt the inventive method to complete the automatic, high precision processing of artificial tooth, reduced the manual of people and participated in, improved the controllability of working (machining) efficiency and quality.
2. to adopt plane cutting method be main orbit generation method in the present invention, formulated the standardization track product process that is applicable to artificial tooth processing process, generated can tooth replacement digital model standard trajectory.
3. the machining area automatic identifying method in the present invention has solved the problem definition of machining area in artificial tooth processing.Thereby avoided manual definition processing curve, improved the automaticity that track generates.
4. in finishing of the present invention, adopted and be different from conventional interference disposal route, improved and interfered the efficiency of processing.
Accompanying drawing explanation
Fig. 1 is process flow diagram of the present invention, and wherein (a) is roughing track product process figure, is (b) finishing track product process figure.
Fig. 2 determines the graphic element of machining area application in the present invention, wherein (a), for 2D limits box, (b) is blank, (c) for 3D limits box, (d) be artificial tooth digital model, (e) for full material, remove region, (f) for connecting bearing rib.
Fig. 3 is Z-direction material removal area of the present invention.
Fig. 4 is the outline line of artificial tooth, (a) is silhouette, is (b) largest contours line.
Fig. 5 is that the present invention cuts friendship contour curve processing schematic diagram, and wherein (a) is initial profile curve, and (b) contour curve for needing to replace (c) is the contour curve after replacement.
Fig. 6 is processing cutter rail track ring tree schematic diagram, and wherein (a) hands over contour curve ring for cutting, and is (b) contour loop tree.
Fig. 7 is machining area schematic diagram, and wherein (a) is individual layer machining area, is (b) multilayer processing region.
Fig. 8 is finishing area schematic, and wherein (a) cuts apart curved surface for Z-direction, (b) for-Z-direction is cut apart curved surface, is (c)-Z-direction machining area.
Fig. 9 is roughing track schematic diagram, and wherein (a) is Z-direction roughing track, is (b)-Z-direction roughing track.
Figure 10 is finishing track schematic diagram, and wherein (a) is Z-direction finishing track, is (b)-Z-direction finishing track.
Embodiment
Below in conjunction with drawings and Examples, the present invention is described in further detail.
Embodiment: artificial tooth processing knife rail generating method of the present invention is mainly completed by roughing and two steps of finishing, the generation of described roughing cutter rail be divided into that Z-direction roughing track generates and-Z-direction roughing track generates two steps, the generation of finishing cutter rail be divided into that Z-direction finishing track generates and-Z-direction finishing track generates two steps.
The method step that concrete roughing track generates, as shown in Fig. 1 (a):
1. determine roughing material removal region:
Z-direction and-Z-direction material removal area adopts following formula to determine: first adopt the artificial tooth 2D shown in Fig. 2 (a) to limit the blank Γ shown in box (the infinite length of Z axis) and Fig. 2 (b) and carry out Boolean operations and draw the 3D restriction box B shown in Fig. 2 (c) 3D, use B 3Dboolean deducts the artificial tooth digital model M shown in Fig. 2 (d), obtains the material removal area γ shown in Fig. 2 (e) total.Use γ totalboolean deducts the connection bearing rib Ψ shown in Fig. 2 (f), thereby obtains the Z-direction material removal area γ of the artificial tooth shown in Fig. 2 zwith-Z-direction material removal area γ -z:
γ total=(B 2D∩T)-M
z,γ -z}=γ total
Wherein: when determine connecting the Z height of bearing rib Ψ, first determine the silhouette of the denture model as Fig. 4 (a) as shown in, using the minimum Z value of silhouette as the Z height value of connection bearing rib;
2. obtain to cut and hand over contour curve:
Adopt the equally spaced planar set vertical with Z axis and Z-direction material removal area γ zask intersection, draw intersection contour curve collection, the initial profile curve drawing is as shown in Fig. 5 (a);
3. process to cut and hand over contour curve collection:
As shown in Fig. 5 (b), the non-outermost contour curve in the slicing layer between the minimum and maximum Z value of silhouettes, replaces with the largest contours line shown in Fig. 4 (b), and the contour curve after replacement is as shown in Fig. 5 (c);
4. generate machining area:
In every layer of section, contour curve ring is abstracted into the form of the contour loop tree shown in Fig. 6 (b) by the nest relation of ring, the region that the node that the degree of depth is even number in tree and child node thereof form, be the material removal area of every one deck, after obtaining material removal area, bias material is removed the inner and outer boundary contour curve in region, thereby obtains the machining area shown in Fig. 7 (a), and Fig. 7 (b) is for calculating the multilayer processing region of gained;
5. track is filled: after obtaining machining area, with row, cut or the track element filling machining area of ring cutting;
6. connect track: the track element obtaining is connected, can obtain being respectively used to shown in Fig. 9 (a), (b) and remove material removal area γ zand γ -zroughing track.
The generation method step of described finishing cutter rail is as follows: as shown in Fig. 1 (b).
1. determine finishing machining area:
Artificial tooth is cut apart along the silhouette shown in Fig. 4 (a), obtain the Z-direction shown in Fig. 8 (a), (b) and-Z-direction cuts apart curved surface, Z-direction machining area is Z-direction and cuts apart curved surface, consider connection bearing rib, actual-Z-direction finishing region is cut apart curved surface for-Z-direction and is removed the region that connects bearing rib gained, as shown in Fig. 8 (c);
2. obtain to cut and hand over contour curve: adopt the planar set that is parallel to Z axis or becomes 30-60 angle with Z axis, intercept initial profile curve set;
3. obtain initial cutter-contact point collection: adopt the method for straight line or two circular fittings to obtain the cutter-contact point collection after discrete.
4. obtain initial cutter location: obtain the method vector at curved surface place, cutter-contact point place, cutter-contact point, along a ball cutter radius of the outside biasing of method direction vector, is obtained to initial cutter location;
5. detection and the processing interfered:
If adopt initial cutter location to drive cutter, can there is local the interference at some recess of denture model in cutter, need to interfere processing, concrete way is: calculate initial cutter location p to the bee-line d of denture model, if bee-line is less than ball cutter radius r, this initial cutter location interferes, and need adjust; Adjustment mode of the present invention is: when obtaining bee-line, have a bit of bee-line on acquisition tooth mould with initial cutter location, calculate the direction of normal n of the curved surface at this some place, new adjustment position p *can adopt following formula to adjust: to make p *for p, repeat said process, until d equals ball cutter radius r:
r p * = r p + | r - d | &CenterDot; n ( r < d ) r p - | r - d | &CenterDot; n ( r > d )
Wherein: r is ball cutter radius, d is that initial cutter location p is to the bee-line of denture model, r pfor vector radius,
Figure BDA0000035966980000072
for the new vector radius of adjusting position, n is direction of normal.
6. connect track: by capable connections of track obtaining, can obtain and be respectively used to Z-direction and-Z-direction finishing track shown in Figure 10 (a), (b).
The present invention is a kind of generation method that meets the standard cutter rail of artificial tooth numerical control processing technology flow process.The method has solved the processing problems of artificial tooth effectively, has reduced artificial participation, has improved working (machining) efficiency, has improved quality stability.
The numerically-controlled machine that the present invention adopts is European patent EP, A2090442.This device is comprised of two separated lathes, and each lathe has independent disposal system, and a device is rebuild for the digitizing of tooth mould, and another is for the digital control processing of tooth mould.Wherein processing unit (plant) comprises three translation shaft, a turning axle and two cutter spindles, and translation shaft is wherein for realizing the translation of X, Y, Z direction.Turning axle can be realized the switching to-Z machine direction by Z.Main shaft 1 is for roughing, and main shaft 2 is for finishing.The cutter rail generating by the present invention, drives cutter first on main shaft 1, blank to be carried out to roughing, obtains roughing model, then roughing model is moved on main shaft 2 and carries out finishing with ball head knife, obtains finishing model.Due to the non-2.5 dimension parts of artificial tooth, so thick finishing of artificial tooth, all need to by cutter along Z-direction processing and-Z-direction processes jointly and completes.The conversion of machine direction, relies on turning axle to realize.

Claims (2)

1. an artificial-teeth processing route generating method, it is characterized in that: first generate for the rough machined cutter rail of artificial tooth, regeneration is for the accurately machined cutter rail of artificial tooth, the generation of described roughing cutter rail be divided into that Z-direction roughing track is produced and-Z-direction roughing track generates two steps, the generation of finishing cutter rail be divided into that Z-direction finishing track generates and-Z-direction finishing track generates two steps;
Described roughing orbit generation method step is as follows: 1. determine material removal area; 2. obtain to cut and hand over contour curve collection; 3. process to cut and hand over contour curve collection; 4. generate machining area; 5. track is filled; 6. track connects;
Described definite material removal area step is as follows: first adopt artificial tooth 2D to limit box B 2Dcarry out Boolean operations with blank Γ and show that 3D limits box B 3D, use B 3Dboolean deducts artificial tooth digital model M, obtains material removal area γ total; Use γ totalboolean deducts artificial tooth and connects bearing rib Ψ, obtains Z-direction material removal area γ zwith-Z-direction material removal area γ -z:
γ total=(B 2D∩Γ)-M
z,γ -z}=γ total
Wherein: when determine connecting the Z height of bearing rib Ψ, first determine the silhouette of denture model, using the minimum Z value of silhouette as the Z height value of connection bearing rib;
Describedly obtain that cut to hand over a contour curve collection step be to adopt equally spaced planar set and the Z-direction material removal area γ vertical with Z axis zask intersection, draw to cut and hand over contour curve collection;
Described processing cuts hands over contour curve collection step as follows: the non-outermost contour curve in the slicing layer between the minimum and maximum Z value of silhouettes, with largest contours line, replace the non-outermost contour curve in the described slicing layer between the minimum and maximum Z value of silhouettes obtaining.
2. according to artificial-teeth processing route generating method described in claim 1, it is characterized in that: described finishing orbit generation method step is as follows: 1. determine finishing region; 2. obtain to cut and hand over contour curve collection; 3. obtain initial cutter-contact point collection; 4. generate initial cutter location; 5. interference checking and processing; 6. track connects;
Described definite finishing region: be that artificial tooth is cut apart along its silhouette, obtain Z-direction and-Z-direction cuts apart curved surface, Z-direction machining area is Z-direction and cuts apart curved surface, actual-Z-direction finishing region is cut apart curved surface for-Z-direction and is removed the region that connects bearing rib gained;
Describedly obtain that cut to hand over a contour curve collection step be to adopt to be parallel to Z axis and to become the planar set of 30-60 angle with Z axis, intercept friendship contour curve collection;
Described interference checking and disposal route are as follows: calculate initial cutter location p to the bee-line d of denture model, if bee-line is less than ball cutter radius r, this initial cutter location interferes, disposal route while interfering is: when obtaining bee-line, obtain on tooth mould and initial cutter location have bee-line a bit, calculate the direction of normal n of the curved surface at this some place, new adjustment position p *adopt following formula to adjust: to make p *for p, repeat said process, until d equals ball cutter radius r:
r p * = r p + | r - d | &CenterDot; n ( r < d ) r p - | r - d | &CenterDot; n ( r > d )
Wherein: r is ball cutter radius, d is that initial cutter location p is to the bee-line of denture model, r pfor vector radius, for the new vector radius of adjusting position, n is direction of normal;
It is described that to obtain initial cutter-contact point collection be to adopt the method for straight line or two circular fittings to obtain the cutter contact point set after discrete; Obtaining initial cutter location is the method vector that obtains curved surface place, cutter-contact point place, and cutter-contact point, along a ball cutter radius of the outside biasing of method direction vector, is obtained to initial cutter location.
CN201010572599.8A 2010-12-03 2010-12-03 Artificial-teeth processing route generating method Expired - Fee Related CN102486641B (en)

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CN108646667B (en) * 2018-03-05 2019-11-05 北京华航唯实机器人科技股份有限公司 Orbit generation method and device, terminal
CN108338848B (en) * 2018-03-27 2019-05-07 北京大学口腔医学院 Stripping type laser tooth preparation method, apparatus, equipment and medium
CN110955213B (en) * 2019-12-09 2020-09-29 上海雷帕罗义齿有限公司 Control system of artificial tooth processing automation line
CN115586749B (en) * 2022-12-12 2023-03-21 深圳市捷牛智能装备有限公司 Workpiece machining track control method based on machine vision and related device

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4436684A (en) * 1982-06-03 1984-03-13 Contour Med Partners, Ltd. Method of forming implantable prostheses for reconstructive surgery
US5452219A (en) * 1990-06-11 1995-09-19 Dentsply Research & Development Corp. Method of making a tooth mold
CN1585625A (en) * 2001-11-15 2005-02-23 3M埃斯佩股份公司 Method for producing dentures

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4436684A (en) * 1982-06-03 1984-03-13 Contour Med Partners, Ltd. Method of forming implantable prostheses for reconstructive surgery
US4436684B1 (en) * 1982-06-03 1988-05-31
US5452219A (en) * 1990-06-11 1995-09-19 Dentsply Research & Development Corp. Method of making a tooth mold
CN1585625A (en) * 2001-11-15 2005-02-23 3M埃斯佩股份公司 Method for producing dentures

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