Product development is difficult, but the job that has challenge sex. In developing a process, stylist must want to use CAD software to draw the product form that wants in the heart into three-dimensional graph model, make according to changing, convenient use fast prototype to make system, computer assist production system, production prototype reachs production. In the future, stylist also can use these data to revise or optimize original design. But occasionally, the client has an objective product only, and the modification with must want to be made again on this foundation certain, so traditional design pattern is handled hard. Because this beard wants expenditure,resource of a lot of manpower and time go the three-dimensional model with scale and same in kind. Especially exterior of a few products is comprised by place of complex free curved surface, the circumstance is more unmanageable. At that time, we must want place to go of another kind of means to manage, three-dimensional begged a technology to offer the way that changes tangible product data quickly instead. For example a small part, three-dimensional seek a technology instead, scanning can be finished to convert its data inside ten minutes several, and with CAD software, must want day or one longer time to complete similar work. Three-dimensional the upriver technology that seeking a technology instead is product development, shorten substantially product development cycle, enhance the competition ability of the enterprise at the same time, suffer domestic and international numerous enterprise to take seriously fully, develop quickly. Three-dimensional the progress that seeks a technology instead is three-dimensional beg a technology to also call converse project instead (Reverse Engineering) , former this kind of technology is to be used at three-dimensional measure reach quality calibrating. Produce the product that come down, can use this technology to measure its exterior dimension and calibrating its quality, contrast next the parameter when be being designed formerly, whether to add add up to a requirement or must want to make revise, optimize etc. This can say three-dimensional seeking a technology instead is the working procedure of upstream of downstream working procedure in products plan process a way of feedback information. 60 time have the century on the scholar puts forward to use computer vision technology (the possibility that Computer Vision) will come to get three-dimensional data. Subsequently, a variety of technologies are come out to collect three-dimensional data by research and development, include among them, light of stereo vision, structure. These technologies are done not have by commercialization, it is very difficult to because collect technology of component of instrument, electron, software when the image of moment,reach computer computation function contented technology requirement. Go up in computer computation function especially, the computer at that time does not have a law to process voluminous data. Arrive on century 80 time, american Cyberware company developed a three-dimensional scanner that uses scanning character, inspect acrobatics successfully to make with Yu Ying. Later, the United States and Japanese company throw natural resources of huge manpower material resources to develop relevant technology and scanning instrument in succession, technical respect includes stripe of range finding of image radar, focusing, Mo Er to wait, and scanning instrument already had nearly 100 to plant to now. Three-dimensional beg technical principle and working flow instead three-dimensional beg a technology to include instead video beg instead, software is begged instead reach objective to be begged instead wait for tripartite face. What study relative to most person at present is objective seeks a technology instead. It is model of CAD of research in kind rebuild and the production of end item. For justice of short for Shaanxi Province, three-dimensional seeking a technology instead is objective model data turns model of design, concept, undertake an analysis to the product on this foundation, revise reach optimize wait for a technology. Principle of Nextpage ◆ job is three-dimensional seeking a technology instead is the primitive data that uses electronic instrument to collect object surface, later reuse software, computation gives the dimensional coordinate that collects data, receive corresponding facial expression. Scanner is right the object makes all-around scanning, next result of changeover of disposal data, three-dimensional model, format, output. Whole unit process of cargo bandling, can divide for 4 measure: (1) object data changes: Use 3 coordinate generally to measure machine or laser scanner to collect the dimensional coordinate cost of object surface. (2) the geometrical feature that analyses an object from inside collection data: According to the attribute of data, undertake breaking up, introduce geometrical feature and the design that identify a method to analyse an object and treatment feature again. (3) the object is three-dimensional the model rebuilds: Use CAD software, make the three-dimensional data after breaking up those who express scale model plan to close, reach the three-dimensional model of objective. (4) examine, amend three-dimensional model. ◆ work flow is three-dimensional the typical job technological process that demands instead basically is pair of existing objective, the apparatus that service data influences, accurate, apace collects the dimensional coordinate cost of exterior outline, next compose builds software of CAM of curved surface, classics to produce CNC to machine cutter track, make objective model on CNC machine tool come out or use fast prototype production machine, produce objective prototype come out. In products plan respect, collection dimensional coordinate is worth, can be opposite hypostatic and three-dimensional model, reply to be revised miscellaneously or innovate again. Fast prototype production machine is readable the documentation that takes STL form, change trains of hypostatic and the curved surface that can nod direct changeover by the cloud or building, three-dimensional model is changed. Three-dimensional data collects what three dimension occupy kind to collect means, the principle that uses according to them, have 3 kinds of kind: It is contact, if 3 coordinate are measured; 2 dispute contact, if structural smooth law, laser is trigonometric,wait; 3 it is method of the scanning that chase a layer, if CT law is mixed,break a scanning law law of nuclear magnetic resonance, automatically to wait. Use which kinds to collect means to depend on by purpose of the appearance of scanning object, size, material, data application. Scan in the market the instrument is a lot of more phyletic, although,collect means endless and identical, but basically comprise by 3 parts; Scan namely device, sensor and software. ◆ contact scans or measurement technique collects means this kind basically is to use 3 coordinate to measure scanning. Collecting means basically is the probe that uses installation to go up in the instrument (Stylus) pointwise collects an object apparently data. When surface of bougie edge object moves, object apparently counterforce makes bougie displacement. Displacement is to pass the bedspring report inside probe to come out. The sensor of join bedspring (what Transducer) can measure displacement is big little, direction. Show through computation each collect the coordinate of three dimensional space of the dot later. Scanning head can install laser to measure the as a result of itself of 3 coordinate measuring instrument rigid structure on machine and design in 3 coordinate, collect data precision tall, do not have special requirement to be being reached to reflex character by the color of the surface of scanning object. When collecting data, bougie is to pressing what be run by the object, a few material are so qualitative softer epispastic glue cannot accurate scanning, because be met by scanning object,be out of shape by bougie. Bougie often moves in tough object surface when, wear away easily, must want so often the diameter of calibration bougie, maintain certain precision. Because it is pointwise,collect data, scanning speed is so relative slower, advocate if be used,measure not quite complex, have the boy or girl friend of a few feature curved surface. On uptodate market, have opportunity of scanning of contact of a kind of appropriative. The Cyclone scanning opportunity that offers by British Renishaw company can collect data of complex object surface curve, every second reachs the rate that select a site at 400 o'clock minutely scanning 3 meters, the operation is apt. Collects data, pass the software that scanning machine provides personally formerly, change into computer to machine medium cutter track, create a pattern directly. The operation principle of smooth law of structure of method of scanning of ◆ blame contact is the illuminant of a definite pattern, project be scanned of the object apparently, illuminant of projectile and referenced face, meet what be put in this position hold back and be happened to be out of shape by scanning object, use different camera lens to shoot the picture of different point of view right now, analyse metabolic illuminant again, calculable the three-dimensional coordinate of whole image of a surface of the object that be measured. The light source that structural smooth law uses with grating hatching relatively general. At present method of metabolic of analytic grating hatching basically has pass li of leaf and phase shift law. And phase shift standard is relative relatively accurate, the advantage of this kind of method is metrical speed the area of very fast, scanning big, equipment carries vehicle case to scan relative to light respect belt, measure field to do not have special requirement. In automobile industry, it is used to generally the large area object such as the automobile body of scanning car. The COMET IV scanner of German Steinblicher company, can arrive from 100 × 75mm2 with the area of scanning 1200 × 1200mm2. Its photograph picture implement can install go up in tripod, optional shift makes high speed to any positions scanning, photograph picture implement OKer on mount manipulator, the object with complex scanning, what resolution can amount to element of 4 million elephant is tall. Can collect favorable data to a few delicate spare partses. Nextpage ◆ laser is trigonometric laser is trigonometric it is to be in the beam of light that be stimulated by what the surface of scanning content uses well-regulated geometry figure, be like point light source or line illuminant, undertake scanning, be met form diffuse reflection spot, smooth band by scanning face, catch installation to receive this spot, smooth ribbon in the image sensor of smooth road, use the dimensional coordinate that trigonometry principle computation gives to be collected to nod next. The technical maturity with trigonometric laser, be used extensively, scanning speed precision is tall, tall. Its image sensor volume is thin and light, installation is convenient. It is OK even its outfit is on 3 coordinate, it is easy that installation disassembles, this is another its characteristic. It also can pledge with scanning material softer object, wait like balata. The scanning precision of Vivid 9i can amount to the blame contact appearance of Konica Minolta company of Japan 0.
05mm, need only 2.
5 seconds can get accurate data. Three-dimensional the application that seeks a technology instead is three-dimensional the application that seeks a technology instead is very wide, industry of the aviation of content of a few hi-tech, spaceflight, auto industry used this technology to be reached at product research and development make. On production industry, collection data is used at the mould to make, products plan, development, the electronic product that consumes a gender for example. In addition, beg a technology to cooperate fast prototype to make a technology instead, can develop the advantage of fast and archetypal technology, application category that enlarges it more. By right of beg technology and concerned software instead, the architect can make in kind quickly, can revise to objective quickly at the same time, optimize and innovation design, can shorten so the cycle of products plan, quickened the occurrence of new product, enhance the competition ability of the company. Three-dimensional the application that seeks a technology instead is as follows integratedly: 1.
Make to fast prototype from the concept. In products plan, some objective use CAD software very hard to build CAD model, will convey design idea, but had three-dimensional after seeking a technology instead, this process becomes simple! 2.
Create a pattern quickly. Technical personnel is used seek technical scanning in kind instead, next collect gotten data, pass special software, be like the Tracecut software of Renishaw company, produce cutter track directly, output reachs CNC Machining center, make a mould come. This kind of circumstance, in the car hind the market (After Market) and electronic consumable are particularly general. The former plant component of the car is opposite more expensive, so apt searchs substitute, the price is relatively cheap. Because the market is quite huge, cause a batch of manufacturer to produce these substitute so. Because do not have data of technology of former plant product, be like the project attempt of objective or CAD model, they are forced to use seek a technology instead, collect the three-dimensional data of objective, change into cutter track, create a pattern directly. Another kind of circumstance is old product of a few stop production, there is demand now. As a result of stop production a long time, primitive data was done not have, be forced to scan existing objective, collect data, turn into cutter track to create a pattern, come true to be produced again. 3.
Make quickly. After begging a technology to convert objective data instead, through having special software, change into practicable data, can wait for software with CAD/CAM/CAE, ERP, machine tool of computer numerical control, have information, data alternant, shorten of production expect time, improve manufacturing efficiency substantially, enhance competition ability. 4.
Be modelled on clipper-built, appearance complex and cannot use artificial method the objective of accurate measurement. Some component of aviation, spacecraft are clipper-built particularly strong, general measurement the instrument is absolutely cannot accurate measure its curved surface! Beg a technology to be able to be in instead an area is petty apparently collect about a hundred 10 thousand, on the three-dimensional coordinate data of ten million, later can build curved surface through software. In the surface of an equal area, three-dimensional coordinate data heals much, built curved surface heals accurate. 5.
The product is duplicate, revise, design. After objective is changed by data, technical personnel can build CAD hypostatic model, curved surface, such stylist can make concerned product quickly revise on software, the design of innovation. Future is looked into as internet sth resembling a net gain ground, get information more easily, commercial competition is intense with each passing day, want what get victory breaks with respect to otherwise to new product puts in the market, shorten manufacturing cycle is competition one of strategy of a key. Begged a technology to produce its effect in time aspect instead, so can wide application develops a field at the product. In technical respect, the rapid development of software, make the operation of data faster, the data processing after scanning is easier; The development of image camera, make collection data more, faster. Such, scanning speed can faster, scanning precision is taller, a variety of technologies develop, the precision that use scanner will come to measure rises greatly. The place on put together is narrated, beg a technology to will have larger development space instead, apply in more domains. CNC Milling