The information of CAD/CAPP of spare parts of blame swing tower that is based on diagnostic map is compositive research

CAD/CAPP/CAM information is compositive it is the key with CIMS compositive information. And in CAD/CAPP/CAM compositive in, the information that should solve CAD and CAPP above all is compositive. Current, implementation CAD/CAPP message is compositive and main have the following kinds of ways: · reframes geometrical substance builds a model: Use an user to define a feature to carry out Boer operation to get the spare parts model of a need on matrix oneself normally. But often produce a feature from definition feature because of the user, accordingly this method restricted the creativity thinking that designs staff inevitably. · feature identifies: Be spot a downstream production activity from inside the hypostatic model of CAD (for example the diagnostic information that CAPP) place needs. Although diagnostic identifying technology already studied old, but the feature that can draw through diagnostic identifying is very finite, and cannot identify alternant sex feature. · is based on diagnostic design: Theoretic the feature that allows to use any sort undertakes designing, but the feature that chooses as a result of products plan and technology design may be abhorrent, below a lot of circumstances, the information that the user still wants to build processing system of diagnostic formative postposition to realize CAD and CAPP or CAM is compositive, produce the advantage that the feature designs adequately hard. · data exchanges a standard: This is a kind of neuter data file that all becomes independent with any CAD/CAPP/CAM systems. Pass this neuter data document (for example STEP standard) the information that realizes each production segment is compositive. Data switch level is current still inextricability because the feature is alternant and brought issue. · feature map: Use all sorts of map principles and method to realize the diagnostic information between different feature collect to change. The design feature map that can center design feature for example becomes the applied feature that all sorts of application features center. Adopting the method of diagnostic map to realize the characteristic with CAD and CAPP compositive information is: ① is foundation of changeover, map with diagnostic model; ② passes compositive information in diagnostic layer; ③ can solve a feature effectively mutual question. The article is research target with be not swing tower spare parts, in realizing CAD, the method that uses diagnostic map designs a feature to make diagnostic transition in CAPP, realize CAD/CAPP information then compositive. 1 construction of system pursues 1.

1 for the system total construction. Systematic cent is map of diagnostic modelling, feature and CAPP input model 3 parts, it is development platform with Pro/Engineer software. After the spare parts builds diagnostic model, its appearance feature and precision feature are changed into production feature to send CAPP input model through different map method. 2 crucial technologies 2.

The automatic classification of 1 feature describes a feature to be able to wait according to circumstance of method of appearance, description, application undertake classified. But these taxonomy all do not apply to the CAD/CAPP information that is based on diagnostic map compositive. To satisfy the requirement of diagnostic map, classification of characteristics (in CAD model) should follow undermentioned principle: (Classification of characteristics should consider 1) the need of diagnostic map, answer with map method relatively. Because diagnostic type is different, often map method is different; (Classification of characteristics wants 2) to come true automatically by computer basis algorithm. Be based on this kind of principle, the characteristic of function of modelling of Pro/Engineer software feature that union uses, the article puts forward a kind of feature that applies to diagnostic map to classify descriptive method automatically. This method builds the hierarchy base in CAD feature model over, according to the planar outline law after the feature is decomposed Xiang Shi measures differentiate criterion to undertake be classifieded automatically to modelling feature. If the structure of diagnostic model pursues 2.

1 is shown, among them appearance feature cent is basic form feature, modelling feature, map class feature and base yuan feature 4 administrative levels. Graph 2.

2 listed the classified circumstance of each appearance feature. The ground floor in appearance feature one by one of basic form feature differentiate the law is helpful for choosing different modelling feature and modelling method. Standard sheet is listed in be helpful for process of precision feature map, face of of all kinds dimension datum is decided really. The 2nd in appearance feature one by one the design feature that modelling feature chooses middling of Pro/Enginer modelling module to use, part the modelling method with corresponding affirmatory some. The three-layer in appearance feature one by one the argument feature of map function (class feature) the ground floor that is located in appearance feature structure, it is the feature that after modelling feature passes group screening, forms. The argument feature cent of map function is 0, 1, 2, 3, 5 4 level, answer relatively with different map method respectively, call class feature again. The definition of 5 class feature is respectively: 0 class feature: Develop attacks the geometrical put oneself in another's position that relation and geometrical relation secure, the appearance of the semantics of i.e. feature and feature is the one to one correspondence feature that does not have 2 justice sexes. If pursue 2.

The columnar aperture in 3(a) , the feature such as conic aperture. Nextpage1 class feature: Comprise a feature all face feature outline are protruding polygon, if pursue 2.

3(b) . 2 class feature: Compositive feature has one outline at least in all face feature outline is sunken polygon, if pursue 2.

3(c) . 3 class feature: By the feature that the combination of the partial face feature in feature of 0 class, 1 class, 2 class forms, if pursue 2.

3(d) . 4 class feature: In passing diagnostic modelling module, rotate (Revolve) , sweep (Sweep) , fold a turn (the design feature that the modelling method place such as B1end) makes, namely curved surface feature, pursue for example 2.

3(e) . 2.

3 for various feature give typical examples. The key that classifies modelling feature automatically the feature that it is class depends on the automatic differentiate of the concave and convex polygon of outline of modelling feature face, its algorithm is as follows: The first pace: The geometry of appearance feature alls over all previous. The geometry that comprises appearance feature forms element and relation to be as follows: · appearance feature: By a certain number of face feature composition. · plane: An ideal geometry is conveyed, namely infinite plane. · face feature: Have attrib border plane. Each feature is OK by comprise to many outline. · outline: One on face feature seals closed circuit, an outline by a certain number of edge composition, and an outline can belong to feature of a face only. · edge: The border of face feature, two plane are by the side of cross a line, the edge belongs to two-phase to make plane. Also belong to two outline at the same time. All over feature of all previous appearance, need the work: · alls over all face feature of all previous spare parts; · alls over all previous the contour line of each feature; · gains an edge of contour line first, all over all previous next all edges, the made ring that makes close (the circle is) of composition of two semicircle arc. : of the 2nd pace? Mei of  of  of Gao of Zhong of negative grain of the ＜ that sentence Jie falls solemn cast  treats  maltose to cast  rapid calumnies cast  M maltose casts  of  of an ancient drinking vessel of Xing Huan of admonish of distant of curb of ⑶ of deceive of Bi of  Xin ù calumnies cast support of department of  of grave of Bi of Jiao of  provide for exemplaries Bi of the Huaihe River, the face feature that has a group namely is located in right hand side forever (RHS) . To outside outline, ergodic direction is a clockwise; To inside outline, ergodic direction is anticlockwise direction. After sort of outline classics RHS, the edge is orderly, if pursue 2.

The order of 4(b) , namely E1, E2, E3, E4 is orderly (RHS) , and the RHS direction of the direction of each edge and outline is consistent. The 3rd pace: The search is bit sunkener. To in an attempt to 2.

The spare parts of 4(a) is exemple, this spare parts is comprised by matrix and a chamfer, matrix is become with rectangular and sectional drawing, groove is if pursue,make on the A face of matrix 2.

Of 4(b) sectional hind drawing and become. Groovy feature is comprised by 10 faces feature, each face feature has only outside outline and without inside outline. Be aimed at B face of groove, the outline outside its is ordinal by E1, E2, ... E8 in all 8 edges composition, n is B face feature outside law arrow. To every apical Pi, the fork that makes what be linked together with this bits have Xiang Bian takes operation: The direction that is like Ni and Ni are the same as to, should nod namely hollow site; It is protruding dot otherwise. The both sides that is linked together with hollow site is sunken edge namely. The implementation that class feature classifies automatically, laid a foundation to determine diagnostic map method. If pursue 2.

1 is shown, 0 class feature because the geometrical appearance of diagnostic semantics and feature is one to one correspondence, need not have appearance feature map; Map of 1 class feature uses dimensional concern to restrain a law; 2 class and map of 3 class feature use half space split plot design; Because 4 class feature is relatively complex, undertake CNC Machining directly. Apparent, because this is planted standard of classification of characteristics is as relative as all sorts of diagnostic map methods should, because this can simplify diagnostic map process, realize the information changeover on layer of spare parts feature effectively thereby. Additional, because use mathematical tool -- with face feature outline outside law arrow direction regards class as basis of classification of characteristics, make the computer undertakes the feature is classified automatically become a possibility. 2.

The grading of process of 2 features map carries out the complexity that considers diagnostic map, it is dimensional concern restrains a law or half space split plot design adopts grading to carry out no matter, in order to simplify map process. 2.

2.

Pretreatment of feature of 1 feature pretreatment includes diagnostic extraction and feature to choose two parts. Diagnostic extraction is the modelling feature extraction that uses the place in diagnostic molding process comes out. Those who be worth to point out is, its semantics did not make clear the modelling feature that extraction gives right now. Extract for example " groovy feature " , this vogue does not know is square chamfer or chamfer of swallow end form. The action that the feature chooses is the modelling feature that gives extraction (body feature) change is face feature, in order to satisfy the need that diagnostic map follow-up matchs a course. Modelling feature cannot direct map becomes as corresponding as its production feature, basically have the following reason: The abstract sex of · modelling feature. Although the abstract sex of modelling feature increased to design flexibility, but of the corresponding concern that also brought diagnostic semantics and diagnostic figure at the same time not only, quality. Because the feature is semantic ambiguous, cause the difficulty of diagnostic map, can appear sometimes afore-mentioned " a pair many " (use when modelling " groove " feature, as a result of the aleatoric sex of sectional appearance, drawing comes out " groove " feature but corresponding a variety of sealed even features. ) or " much righter one " (the groovy feature of modelling of the direct feature that use opening and the round drawing that use plane but corresponding aperture feature) circumstance. Nextpage · inspects region dependence: To same part, inspect region to differ the modelling method that decided to use is different, specific used modelling feature also not identical. If pursue 2.

5 shown parts: Learn to analyse angle from force, design personnel considers as muscle, modelling feature is matrix add on the feature 2 muscle feature; From the angle of treatment, design personnel considers as groove, modelling feature is base feature of chamfer of the purify on the feature. The spare parts model that designs angle of force credit analyse is used at treatment, if do not have diagnostic map, won't get machining the groovy feature of a need, what inspect region accordingly is different, it is to cause cannot the another reason of direct map. Occurrence interference of · modelling feature. Original feature not answer exist, make new feature, pursue for example 2.

6 Central Plains come model antrum feature changes blind chamfer feature. In view of afore-mentioned circumstances, body feature should decompose face feature layer commonly inference of aspirant travel geometry. 2.

2.

The differentiate method that type of 2 appearance feature matchs appearance feature type is, go out to be mixed by the appearance feature that decomposes gotten face feature to be cut really when reset certainly the feature is semantic. Appearance feature type matchs the space that is based on geometrical appearance to restrain a relation, among them the space that binary tie concern limitted two plane concerns. To in an attempt to 2.

Chamfer of the blind in 6 spare partses is exemple, its the tie requirement that two flank should satisfy is: Appearance of · double geometry is planar; The photograph of quantity of law Xiang Shi of two plane of · to; Two plane of · see each other to vector direction in the law. The rest may be deduced by analogy, the space that can decide 4 plane that make blind chamfer should be satisfied restrains a relation. With this kind of space tie concern is match a basis, face feature recombines the appearance of body feature geometry that make to reach its to cut diagnostic semantics to be able to decide truly. Graph 2.

The 7 chamfer that it is blind restrain a relation. Express feature of the 1 chamfer that it is blind to pass the output result after matching. 2.

3.

3 features attribute identifies diagnostic attribute to identify those who conduce to farther judgement feature to concern character, include diagnostic freedom to spend, open sex and feature design diagnostic outline fiducial. (1) feature freedom spends: Cent is spent for circumgyrate freedom (2 π , 2 π , 2 π ) spend with translation freedom (1, 1, 1) , among them 2 π represent numerical value the feature can circle some axis to do circumgyrate to move; Numeric 1 state the feature is OK two-way translation moves; If numerical value all is 0, criterion the feature moves in the circumgyrate of this axial and two-way shift all is restricted; If numerical value is 1/2, criterion the feature can be moved in one-way and infinite carry only, graph 2.

A certain number of circumstances that freedom of 8 illustrate feature spends. (2) feature outline opens a gender: Show the feature is on some direction of cutting tool can cut a gender. This to determining direction of cutting tool feed, choice treatment fixed position is standard have important sense. Diagnostic outline opens a gender to use a figure 2.

7 in one-way or two-way arrowhead expresses. (3) feature design is standard: Precision of the dimension in be precision feature, form precision provides a basis surely really. 3 conclusion are in CAD/CAPP compositive environment, diagnostic map is spare parts information realizes compositive efficient way on diagnostic layer. The grading of the automatic taxonomy that introduces a feature and diagnostic map is carried out wait for crucial technology, conduce to simplify diagnostic map process, implementation CAD designs the transition that the feature makes in CAPP. CNC Milling