Reverse?Engineering (RE) is a description of the product design process. Is relative to the current forward engineering, forward engineering is that we first design drawings, and then processed according to the drawings of the product in kind, and reverse engineering is currently available in kind through the three-dimensional laser ultra-numerical and reverse software processing, restored to the computer model, and can be modified and improved.
In the general concept of engineers and technicians, the product design process is a process from scratch, that is, the designers first in the brain conceptualization of the product's shape, performance and general technical parameters, and then through the drawings to establish a three-dimensional digital model of the product, and ultimately the model will be transferred to the manufacturing process, the completion of the product's entire design and manufacture of the cycle. Such a product design process we call "forward design" process.
Reverse engineering product design can be thought of as a "from something to nothing" process. Simply put, reverse engineering product design is based on the product model already exists, the reverse introduction of product design data (including design drawings or digital model) process. In this sense, reverse engineering has been used in industrial design for a long time. Early ship industry commonly used in the hull sampling design is a good example of reverse engineering. With the wide application of computer technology in the manufacturing field, especially the rapid development of digital measurement technology, the product modeling technology based on measurement data has become the main object of concern for reverse engineering technology. The spatial data on the surface of the object obtained by digital measuring equipment (such as coordinate measuring machine, laser measuring equipment, etc.) needs to be used to establish the three-dimensional model of the product using reverse engineering technology, and then the CAM system is used to complete the manufacturing of the product. Therefore, reverse engineering technology can be regarded as a general term for the related digital technology and geometric modeling technology that transforms product samples into three-dimensional models.
The implementation process of reverse engineering is a multidisciplinary and multidisciplinary collaborative process. As we can see from Figure 1, the entire implementation process of reverse engineering includes the process from measurement data acquisition, processing to conventional CAD/CAM system, and finally integrated with the product data management system (PDM system). The implementation of engineering requires a high degree of synergy and integration of people and technology.?
Reverse engineering implementation principle:
Reverse engineering in the CAD/CAM system reverse engineering technology is not an isolated technology, it and measurement technology and existing CAD/CAM systems are inextricably linked. However, in the actual application process, due to the majority of engineers and technicians do not know enough about reverse engineering technology, reverse engineering technology and the existing CAD/CAM technology is equivalent to the existing CAD/CAM system with the technical level of reverse engineering technology, often resulting in people's mistrust and misunderstanding of reverse engineering technology.
From a theoretical point of view, reverse engineering technology can reconstruct a three-dimensional model that is fully compatible with the existing CAD/CAM system according to the measurement data of the product, which is the ultimate goal of reverse engineering technology. However, we should see that the current technology that people have, including engineering and purely theoretical (such as surface modeling theory), have not been able to meet this requirement. Especially for the more popular large-scale "point cloud" data modeling, is far from the degree that can be directly applied in the CAD system. Therefore, we believe that the current reverse engineering CAD technology and existing CAD / CAM system relationship can only be a complementary relationship. Existing CAD/CAM system after decades of development, both from the theory and practical application have been very mature, in this situation, the existing CAD/CAM system will not and can not meet the special requirements of reverse engineering modeling change system bottom. On the other hand, a large number of modeling methods used in reverse engineering technology can be completely borrowed from the existing CAD/CAM system, without the need to build a new platform.
Based on this analysis, we believe that reverse engineering technology in the entire manufacturing system chain is in the subordinate, auxiliary modeling position, reverse engineering technology can use the existing CAD/CAM system, to help it achieve their own work can not be completed. With this understanding, we can understand why reverse engineering technology (including the corresponding software) has not been the mainstream of the market, and most of the CAD / CAM system include reverse engineering module or third-party software packages such a situation.
Reverse engineering technology in the mold industry
From the concept of reverse engineering and technical characteristics can be seen, reverse engineering applications are mainly aircraft, automobiles, toys and home appliances and other mold-related industries. In recent years, with the development of biological and material technology, reverse engineering technology has also begun to be applied in medical fields such as artificial biological bones. However, its main application area is still in the mold industry. As the mold manufacturing process often need to repeat the test punch and modify the mold profile. If the measurement finally meets the requirements of the mold and inverse its digital model, in the repeated manufacture of the mold can be used to generate the processing procedures of this alternate digital model, can greatly improve the efficiency of the mold production, reduce the cost of mold manufacturing.
Reverse engineering technology in China, especially in the production of a variety of automobiles, toys, supporting parts of the region, the enterprise has a very broad application prospects. These areas, enterprises often need to manufacture molds according to the sample provided by the customer or directly processed products. In these enterprises, measuring equipment and CAD/CAM system is essential, but due to the application of reverse engineering technology is not perfect, which seriously affects the accuracy of the product as well as the production cycle. Therefore, the combination of reverse engineering technology and CAD/CAM system is of great significance to the application of these enterprises. We have experienced this during our many years of technical service. On the one hand, each mold enterprise is very welcome to promote reverse engineering technology in the enterprise, but on the other hand, it suffers from the lack of necessary guidance and suitable software products. This situation seriously restricts the promotion of reverse engineering technology in the mold industry.
Compared with the application of CAD/CAM system in our country for decades, reverse engineering technology for engineers and technicians to understand only a decade or even a few years of time. Although the time is short, but the reverse engineering technology extensive application prospects for most engineers and technicians have been concerned about, which is to improve the overall technical content of China's mold manufacturing industry, and thus improve the market competitiveness of the product has an important role in promoting the ?
Reverse engineering software
The implementation of reverse engineering requires the support of reverse engineering software. The main role of reverse engineering software is to receive product data from measurement equipment, through a series of editing operations, to obtain excellent quality curve or surface model, and through the standard data format will be transported to the curve surface data to the existing CAD / CAM system, in these systems to complete the final product modeling. Since it cannot fully meet the user's demand for product modeling, it is difficult for reverse engineering CAD software to compete with existing mainstream CAD/CAM systems, such as CATIA, UG, Pro/ENGINEER and SolidWorks. Many reverse engineering software to become the third party software of these CAD/CAM systems. For example, UG uses ImageWare as the software to complete reverse engineering modeling in UG series products, and Pro/ENGINEER uses ICEM?Surf as the support software for reverse engineering module. In addition there are some independent reverse engineering software, such as GeoMagic, etc. These software generally have diversified functions. For example, GeoMagic can handle the modeling of tomographic interface data represented by CT and MRI data in addition to geometric surface modeling, thus making the software quite competitive in the medical imaging field. Some other reverse engineering software as part of the overall series of software products, whether the data model or geometry engine are consistent with other components in the series of products, the benefits of doing so is that the model generated by the reverse engineering software can be directly into the CAD or CAM module, to achieve a seamless integration of data, this type of software on behalf of the DELCAM company's CopyCAD.
Below are a few of the more famous reverse engineering software.GeoMagic (www.geomaigc.com), the reverse engineering software from the U.S.-based RainDrop Corporation, has a wealth of data processing tools that allow it to quickly construct multiple continuous surface models based on measured data. The software's application areas include everything from industrial design to medical simulation, and its users include major manufacturers such as General Motors and BMW.
ImageWare (www.imageware.com), the reverse engineering modeling software provided by UG?NX, provides powerful measurement data processing, surface modeling, and error detection capabilities. It can handle tens of thousands to millions of point cloud data. The CLASS?A surfaces constructed from these point cloud data have good quality and surface continuity, and ImageWare's model checking function can easily and intuitively display the error between the constructed surface model and the actual measurement data, as well as the geometric tolerances such as flatness, true roundness, and so on.
CopyCAD (www.delcam.com)CopyCAD is one of a series of CAD products from DELCAM, a British company that deals with surface modeling of measured data. DELCAM's products cover the entire process from design to manufacturing and inspection. They include PowerSHAPE, PowerMILL, PowerINSPECT, ArtCAM, CopyCAD, PS-TEAM and many other software products. As part of the range, CopyCAD integrates well with other software in the range.
RapidForm (www.rapidform.com)RapidForm is a reverse engineering software developed by INUS in Korea. It is mainly used for surface modeling of measurement and scanning data as well as medical image modeling based on CT data, and it can also complete the measurement modeling of artwork as well as the generation of advanced graphics.RapidForm provides a complete set of tools for model segmentation, surface generation, and surface detection, and it allows users to conveniently utilize previously constructed curved meshes to be applied to the new model reconstruction process after scaling.
The above introduction is the more common reverse engineering software, in the domestic can see the commercialization of reverse engineering software are foreign. Although there is also research in reverse engineering software in China, it is mainly concentrated in several universities. Tsinghua University, Zhejiang University, Nanjing University of Aeronautics and Astronautics in this area of research is more in-depth, the results of these studies also have some of the software products in the form of appearances, due to the stability of the system, operability and other aspects of the reasons, these research software does not yet have the conditions to compete with the foreign commercialized software.
The reverse engineering software QuickForm? developed by domestic professionals in the field of reverse engineering is one of the better domestic reverse engineering software. It adopts an advanced geometry engine and runs with good stability and maneuverability. Since the developers have rich experience in implementing reverse engineering, the function settings and operation methods in the system are in line with the habits of domestic users, which are not available in foreign software.Another advantage of QuickForm is the price advantage, and the price of QuickForm is extremely competitive in the similar software. At the same time, the use of domestic software is also the support of the domestic manufacturing and software industry.