Of CNC Machining visible emulate

Foreword as collateral project, nimble make, fictitious make the progress that waits for advanced production technology, the machines a process condition that the product can forecast before the requirement is being made and product quality. Before actual CNC Machining, logarithm accuses code (NC code) undertake emulation, test and verify machines the feasibility of code and best sex, show cutting process OK and intuitionisticly consequently and forecast cutting result, what change to optimize cutting craft, choice to machine parameter to provide a basis is more and more important. The emulation cent of CNC Machining is emulated for geometry and physics emulates two parts. The main purpose that geometry emulates is the validity of method of cutting tool of test and verify, code of treatment of test and verify is feasible, emulate for physics provide necessary cutting geometry information, wait like deepness of cutting of speed of material purify bulk, cutting, axial. If physical copy Allah is mechanical emulate, it is the core part that process of fictitious CNC Machining emulates, its connotation considers all sorts of factors in actual cutting integratedly namely, build plan to combine the mathematical model with high rate with actual cutting, realize fictitious treatment and effective treatment from real significance " without seam join " , of contented and fictitious CNC Machining be enmeshed to feel and feel interactively. Software is used in all sorts of business in, the geometry that already had a lot of differring emulates software, a lot of research groups also are in home to try ceaselessly to develop new algorithm to raise geometry to emulate indication accuracy and efficiency. Among them, the comparison that emulates respect processing in geometry with the Visual NC in Dassault company Delmia is outstanding. The respect is emulated in physics, although already had a few business to be able to undertake emulation with software, home also has a few to study the group devotes oneself to physical copy to study really, but, the research of this respect still was not perfected. 2.

The geometrical copy that the geometry in CNC Machining emulates CNC Machining is the imitate process that the exterior that points to the contrail that moves according to cutting tool and cutting tool has excising to workpiece really. Traditional method is to use try cut a way, although use cheap material to use actual machine tool to undertake cutting, whether be existence collides or interference in order to detect. Cost of this kind of method is high time-consuming long, reduced manufacturing efficiency. Benefit is opposite with the computer now the imitate of CNC Machining process, use computer simulation cutting tool namely along treatment method and by treatment workpiece (semifinished product) the opposite motion between, the monitoring that realizes the process such as mobile to machining medium cutting tool, cutting and the test and verify to treatment code validity. This kind of method greatly shortened preparative time of production. Commonly used method has two kinds: Disperse law and hypostatic model law. 2.

Law of disperse of 1 disperse law includes to inspect normally to disperse law and triangle piece disperse law two kinds. Be based on image space inspect to disperse law it is relatively common method, do its work basically is the principle: ? Le of faint the tenth of the twelve Earthly Branches relatively the indication cache that the result that  of ぜ of ⒐ of blood clam Qian steals poisonous? to take the foremost color in both to serve as Boer operation keeps grating monitor directly. Because make one dimension on direction of line of sight only Boer operation, and operation and show close 2 for one, so this kind of method has very tall real time sex. Is its defect: ? ? of Piao of Ge of  of  of  of  of bifurcation of home of a kind of reed of  of border of  of head of Jian of leech   and these dots resembling element rely on indication screen, cannot undertake gyral to machining a result so, the operation such as enlarge, undertake machining error examines hard at the same time. Another kind of method is trigonometry piece disperse law. Trigonometry piece disperse law is to point to, use work trigonometry piece disperse is changed, will go up exterior disperse is even lattice, become these latticedot matrix link trigonometry reseau again. When imitate cutting, the height according to cutting tool expresses the height of face lattice on constant change, undertake apply colours to a drawing of sense of reality to trigonometry reseau again, emulate the process of CNC Machining with this. In trigonometry piece in disperse law, its key is trigonometry piece the contradiction between precision and computational speed. Namely, trigonometry piece more concentrated, the clear accuracy of image is taller, and operation rate is slower, contrary, trigonometry piece more few and far between, image accuracy is lower, but operation speed can be accelerated however. Be based on this contradiction, [Put forward to use trigonometry more in the area with the complex form that is necessary to be described accurately in 1] piece, and in the area with simple appearance little use triangle piece method. Again [the method that area also used to search the triangle that needs heavy paint in 2] will improve operation efficiency, put forward assess triangle piece 3 algorithmic index: Send closely gender, conservative sex and evaluate efficiency. Efficiency of law of more hypostatic model wants disperse way normally tall a lot of, can realize indication real time gender basically, but as a result of disperse of face of will hypostatic Xiang Ping, make a result medium lacked the three-dimensional information with a lot of original work. 2.

Law of model of substance of law of 2 hypostatic model can offer the geometry with three-dimensional the wholest form and structure and develop to attack information, can undertake accurate procedure is emulated with the knife orbit test and verify. The model in emulating has mathematical model and similar model, among them mathematical model includes GSC and B-rep, similar model includes 8 forked trees, unit. Emulate in inchoate substance in, basically undertake operating to mathematical model. In body element construction expresses in, cutting can regard as Boer decreased process, in attrib border notation, cutting can see those who make workpiece appearance reframe. But these calculation that show pattern are complex degree too tall, (of CSG complex spending is N4, among them N is to walk along a knife to seek the number that make) a few methods that are based on similar model also are introduced in hypostatic model law, be like [the Cuboid-array model method that mentions in 3] , be a kind of model that is based on 8 fork to cultivate be out of shape. On the other hand a few emulation methods that are united in wedlock with disperse law photograph, dimensional disperse notation. In this kind of method, the space that is in workpiece differentiates to have the woof of simple data structure, be like Z-Buffer, g-Buffer, dexel, simplify from this the Boer operation operation between workpiece model and cutting tool scanning, improved efficiency thereby. Say on the whole, the efficiency of hypostatic model law wants under disperse law, nevertheless, the complete geometrical information that hypostatic model law withheld three-dimensional substance and develop attack information, can be next observation and physics are emulated provide valid data, is not to be like disperse law, it is the pure emulation effect that creates picture effect only. Increase of speed ceaselessly as the computer, hypostatic model law will get more and more extensive apply. 3.

The physics in CNC Machining emulates physics basically is mechanical emulate, research work is in the physical condition when cutting, true to physical copy mechanism research is only thorough, talent is real on the meaning contented and fictitious satisfaction goal, the true map that machines a process actually to go up in the computer namely. The main content that physics emulates includes cutting force to emulate, machining error is emulated, those who cut bits generate a process to emulate, the deflection of cutting tool, be out of shape and wear away emulate, the vibration that reachs machine tool of numerical control cutting and temperature are emulated etc. Cutting force is physics emulates medium main factor, the function that is thought purify of unit time stuff is led normally. Accordingly attainable cutting tool roughly circumstance getting power, later reoccupy is finite yuan what the law undertakes be handlinged further getting cutting force go up in cutting tool is specific distributing. The factor that affects workpiece machining error basically is fixed position error, other influencing factor still includes on size error of error of precision of machine tool motion, cutting tool, main shaft to move, slideway is out of shape, the error that heat of clamping force, cutting tool, spare parts is out of shape and flexibility is out of shape error and treatment method are caused. According to the influence of these errors rate size differs, add the idea that authority is worth, undertake integrated judge can get the total error that processes precision blurring. The real time copy that cutting makes a process is virtual numerical control and effective treatment really " without seam join " the main link that demonstrates with synchronism, of cutting generate, reel-up, break off and the effect that generated appearance suffers a lot of elements, the material of fluid of the geometrical appearance that is like cutting tool, cutting, workpiece and cutting tool, and the circumstance getting power of cutting tool and workpiece. Consider to make clear, when cutting ply very hour, cutting ply and cutting force show linear concern. Of cutting tool wear away and the affects CNC Machining machining error with very can big deflection and product quality. Experimental data makes clear, the cutting tool of distance of every unit feed and unit area wears away bulk and cutting temperature and press stress to concern. Simplify cutting tool for cantilever bridge, its basically get the cutting power that force gets for knife head, classics computation can get the deflection of cutting tool. Machining temperature is a of influence cutting tool and workpiece treatment attribute main factor, among them the treatment process of grinding and turning is successive, use formulary description more easily, and milling is intermittence cutting, need is used a few amend will have a description. The vibration that motivation may cause also machines those who affect work exterior precision. Can provide the basis that avoid or reduces vibration to the machine tool is emulated oscillatorily in real time, logical choice machines a condition. In oscillatory to the machine tool influence, have two more remarkable factors: (1) the kinetic parameter of machine tool, workpiece and cutting tool and the position that follow cutting force vector and the system that direction changes. (2) state of cutting tool appearance and the treatment material related to cutting force, material, cutting, cutting tool wears away type and wear extent be out of shape. The attrition force that cuts bits and tool cover is affecting a lot of factors such as the temperature of the figure that cuts bits, system. Attrition force enters workpiece to be change arrive inside the time that leaves work in blade of cutting tool cutting, cutting is affected each other between the size of attrition force and systematic temperature, this coordinates these a few elements each other with respect to need, and get best treatment result. These elements that give out just can affect a few factors of final work quality in CNC Machining, these also can be affected each other between the element, some also can become the factor that direct consideration needs in the design, ought to coordinate each other when considering these factors integratedly so machine a result in order to get first-rate. 4.

Numerical control is emulated apply mediumly with software in business the function that there had been relatively perfect numerical control geometry to emulate in software is used in a lot of common business, two when Dassault company confronts below software that can undertake CNC Machining geometry is emulated have a few simple introductions. 4.

1The software of large CAD modelling that the numerical control geometry in Catia emulates Catia to be rolled out as Dassualt company with by people place hep, it included powerful CAD modelling function not only, also included powerful CAM function and basic CAE function. In its CAM function, the geometry that can undertake CNC Machining is visible emulate. The visible copy in Catia is really before G/M code is generated, be confined to collide to whether happening between cutting tool and workpiece, and whether can the method of place set undertake accurate and complete treatment undertakes examining. Its are specific the process is as follows: Mix in the work that needs treatment certainly and treatment parameter have a youthful look of parameter of affirmatory cutting tool becomes cutting tool contrail, undertake cutting to workpiece through this contrail, the classics of workpiece reductive state of cutting process the feedback after visible processing gives an user. In this process, workpiece is fixed, and cutting tool photograph is mobile to workpiece, when cutting tool and workpiece intersect, subtract from inside workpiece the part that intersect. This process considered the local interference of cutting tool and workpiece only, and when cutting part and workpiece collide, the blame when cutting tool won't show. And workpiece is secured and cutting tool shift does not accord with actual treatment state sometimes, also did not consider the collision of machine tool and cutting tool or workpiece to go in. Reason emulates a process this is only probably the abecedarian emulates a process. 4.

The Visual NC module in the Delmia that the numerical control geometry in 2Visual NC emulates Dassualt offerred a comprehensive specific geometry to emulate a process, considered the actual condition of the machine tool to go in, use the G/M code that accords with place to use a machine tool to undertake controlling, the right place that realized geometry to go up sees namely earning. In Visual NC, those who use is B-rep model, attack the object with geometrical information and develop information description. When using this kind of model to undertake cutting is emulated complex degree for N or N2, the process of cutting tool and workpiece cutting can regard geometrical information and develop to attack the new operation of information. In the model when building, produce a drop only, line, face, the simple simple element such as polygon, can lower the complex rate of the model. On the other hand, it offerred the alternative of approximate precision when building a model. Be like: When building round model, it can enquire the acme that makes a circle is counted, the similar rate that the user can control place to give graph and true circle through installing this option (install 3 acme to be a triangle, 4 are a square, the number that should order is sufficient big when, can behave a circle approximately) . Its emulate the first of the process is machine tool model to build, because consider in the actual condition of machine tool of Visual NC lieutenant general CNC Machining process is medium, so need builds machine tool model. The CAD function that machine tool model can take oneself through its is built, OK also by generate in other system guide, must notice when, the file that guides is a whole in Visual NC, still need to have associated setting further. Cent of machine tool model is two large parts, secure part and athletic section. Generally speaking, in the model when building, each athletic sections of need general machine tool are separate, but fixed part can serve as a whole. In the its origin should notice when building X of athletic section, y, z direction, because this will be its motion,control direction is mixed with the machine tool the direction when other part is associated. Should move to undertake athletic correlation partly to each after the model is built, the serial number of the athletic direction that sets it and the axis in MIMIC language, the biggest range that sets each parts to be able to move on its feed direction. The 2nd pace needs to set workpiece, cutting tool and clamping apparatus, workpiece, cutting tool and clamping apparatus can be transformed by entity and become, in cutting tool fractionize is cutting part and knife handle part, common cutting tool divides composition by these two, only cutting part and workpiece intersect to just can undertake cutting. The collision that needs pair of each parts after workpiece cutting tool has been installed with clamping apparatus undertakes installing. Generally speaking, machine tool and workpiece, cutting tool and clamping apparatus undertake colliding detecting entirely can, when producing collision, collision part is met by highlight. Install in geometrical exterior of the system after ending, need undertakes installing to the control of the machine tool, the language that its install is MIMIC language, the element such as its athletic condition through controlling a machine tool and athletic attribute will control the shift of the machine tool, after using proper MIMIC language, the response rate that fictitious machine tool gives G/M code to place ought to with actual and identical. Can guide after all setting ends numerical control code undertakes machining emulation to its, in emulation process, can be opposite the cutting process of workpiece, the athletic condition of cutting tool, whether to produce interference, whether does the machine tool exceed the state such as athletic limits to undertake detecting, can be opposite after getting a result workpiece undertakes metrical, the requirement that is versed in whether the dimension of an earning after treatment accords with treatment in order to examine (the error that does not contain workpiece) . Look from whole, the geometry to CNC Machining emulated Visual NC to had achieved more perfect degree, in geometry emulation place hopes gotten data and effect had been considered to go in, the system that the setting that joined a machine tool makes has bigger adaptability. And the requirement that also can satisfy real time to show in indication career respect. 5.

The copy that sums up CNC Machining is really modern one of make important process, it offerred the assurance of reliable basis and quality for actual manufacturing process. In the process that emulates to geometry, research basically is centered in the efficiency of operation and the integrated optimization of indication precision. Do not have too perfect research in true to physical copy course, business also does not have special module with the emulation in software, it is finite only yuan apply. True to physical copy research still has very large space. CNC Milling CNC Machining