Use computers and their graphics devices to help designers complete the design work. Cad for short. In engineering and product design, computers can help designers undertake tasks such as calculation, information storage and drawing. In design, computers are usually used to calculate, analyze and compare many different schemes to determine the best scheme; All kinds of design information, whether digital, literal or graphic, can be stored in the internal memory or external memory of the computer and can be quickly retrieved; Designers usually start with sketches, and the heavy work of turning sketches into working drawings can be handed over to computers. The design results automatically generated by computer can be quickly displayed graphically, which is convenient for designers to judge and modify the design in time; Computers can be used to process graphic data related to editing, enlarging, reducing, translating and rotating graphics. Cad can reduce the repetitive work of designers such as calculation and drawing, focus on the design itself, shorten the design cycle and improve the design quality.
[Edit this paragraph] Development overview
In 1950s, the first computer drawing system was born in America, and passive computer-aided design technology with simple drawing output function began to appear. In the early 1960 s, cad surface patch technology appeared, and commercial computer drawing equipment was introduced. In 1970s, a complete cad system began to take shape. In the later period, raster scanning display which can produce realistic graphics appeared, and various forms of graphic input devices such as manual cursor and tablet were introduced, which promoted the development of cad technology. In 1980s, with the appearance of powerful microprocessors and storage devices made of VLSI, engineering workstations came out, and cad technology was gradually popularized in small and medium-sized enterprises. Since the mid-1980s, cad technology has developed towards standardization, integration and intelligence. Some standard graphical interface software and graphical functions have been introduced one after another, which has played an important role in promoting the popularization of cad technology, software transplantation and data enjoyment. The structure of the system has changed from a single function to a comprehensive function, and a computer integrated manufacturing system integrating computer-aided design and computer-aided manufacturing has emerged. The application of solidification technology, network technology, multiprocessor and parallel processing technology in cad greatly improves the performance of cad system. Artificial intelligence and expert system technology are introduced into cad, and intelligent cad technology appears, which greatly enhances the problem-solving ability of cad system and makes the design process more automatic. Now, cad has been widely used in electronic and electrical, scientific research, mechanical design, software development, robotics, clothing, publishing, factory automation, civil construction, geology, computer art and other fields.
[Edit this paragraph] System composition
Usually, it is based on an interactive computer system with graphic function. The main equipment includes: computer host, graphic display terminal, graphic input board, plotter, scanner, printer, tape drive and various software.
Engineering workstation generally refers to a single-user interactive computer system with super minicomputer function and three-dimensional graphics processing ability. It has strong computing power, uses standard graphics software, has a high-resolution display terminal, and can work in a local area network with resources, forming the most popular cad system.
Personal computer (pc) system is cheap, easy to operate and flexible to use. Since 1980s, the performance of pc has been continuously improved, and the software and hardware have developed rapidly. In addition, with the application of graphics cards and high-resolution graphic displays and the development of pc network technology, a large number of cad systems composed of PCs have appeared and are on the rise.
Quadratic Surface Designed by Computer —— Sphere
Graphic input and output devices In addition to the computer host and general peripheral devices, computer-aided design mainly uses graphic input and output devices. Interactive graphics system is particularly important for cad. The general function of the graphic input device is to send the coordinates of each point on the plane to the computer. Common input devices include keyboard, light pen, touch screen, joystick, trackball, mouse, tablet and digitizer. Graphic output devices are divided into soft copy and hard copy. Soft copy devices refer to various graphic display devices, and human-computer interaction is essential; Hard copy devices are usually used as attachments for graphic display, which copy images to the screen for storage. There are three commonly used graphic displays: directional beam display, storage tube display and raster scanning display. Directional beam display is the earliest application. In order to make the image clear, the electron beam must constantly redraw the graphics, so it is also called refreshing display. Easy to erase and modify graphics, suitable for interactive graphics. The storage tube displays the saved images without refreshing, so it can display a large amount of data at a low price. The raster scanning system can provide color images, and the image information can be stored in the so-called frame buffer memory, so the image resolution is high.
In addition to computer software, such as operating system and compiler, cad mainly uses three kinds of software: interactive graphic display software, cad application software and data management software.
Interactive graphic display software is used for window opening, editing and viewing, graphic transformation and modification, and corresponding human-computer interaction. Cad application software provides geometric modeling, feature calculation, drawing and other functions to complete various special designs for various professional fields. The four elements of constructing application software are: algorithm, data structure, user interface and data management. Data management software is used to store, retrieve and process a large amount of data, including text and graphic information. Therefore, it is necessary to establish an engineering database system. Compared with the general database system, it has the following characteristics: the data types are more diverse, the entity relationship in the design process is complex, the values and data structures in the database often change, and the designer's operation is mainly a real-time interactive processing.
The basic technology mainly includes interactive technology, graphic transformation technology, surface modeling and solid modeling technology.
In computer aided design, interactive technology is essential. Interactive cad system means that when users design with computer system, people and machines can exchange information in time. With the interactive system, people can conceive, sample and modify at the same time, and the display results of each step can be seen from the screen of the graphic terminal at any time, which is very intuitive.
The main function of graphic conversion is to connect the user coordinate system and the graphic output device coordinate system; Translation, rotation, scaling and perspective transformation of graphics; Graphic transformation is realized by matrix operation.
Computer design automation Computer-built cad aims to realize the automation or semi-automation of computer-built design and development process. The research contents include functional design automation and assembly design automation, involving computer hardware description language, system-level simulation, automatic logic synthesis, logic simulation, microprogram automation, automatic logic division, automatic layout and wiring, and the corresponding interactive graphics system and engineering database system. Integrated circuit cad is sometimes included in the scope of computer design automation.
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[Edit this paragraph] What is Computer Aided Design (CAD)?
Computer-aided design refers to the use of computers and their graphic devices to help designers carry out design work. CAD for short. In engineering and product design, computers can help designers undertake tasks such as calculation, information storage and drawing. In design, computers are usually used to calculate, analyze and compare many different schemes to determine the best scheme; All kinds of design information, whether digital, literal or graphic, can be stored in the internal memory or external memory of the computer and can be quickly retrieved; Designers usually start with sketches, and the heavy work of turning sketches into working drawings can be handed over to computers. The design results automatically generated by computer can be quickly displayed graphically, which is convenient for designers to judge and modify the design in time; Computers can be used to process graphic data related to editing, enlarging, reducing, translating and rotating graphics. CAD can reduce the labor of designers, shorten the design cycle and improve the design quality.
[Edit this paragraph] Overview of ]CAD development
In 1950s, the first computer drawing system was born in America, and passive computer-aided design technology with simple drawing output function began to appear. In the early 1960 s, cad surface patch technology appeared, and commercial computer drawing equipment was introduced. In 1970s, a complete cad system began to take shape. In the later period, raster scanning display which can produce realistic graphics appeared, and various forms of graphic input devices such as manual cursor and tablet were introduced, which promoted the development of cad technology. In 1980s, with the appearance of powerful microprocessors and storage devices made of VLSI, engineering workstations came out, and cad technology was gradually popularized in small and medium-sized enterprises. Since the mid-1980s, cad technology has developed towards standardization, integration and intelligence. Some standard graphical interface software and graphical functions have been introduced one after another, which has played an important role in promoting the popularization of cad technology, software transplantation and data enjoyment. The structure of the system has changed from a single function to a comprehensive function, and a computer integrated manufacturing system integrating computer-aided design and computer-aided manufacturing has emerged. The application of solidification technology, network technology, multiprocessor and parallel processing technology in cad greatly improves the performance of cad system. Artificial intelligence and expert system technology are introduced into cad, and intelligent cad technology appears, which greatly enhances the problem-solving ability of cad system and makes the design process more automatic. Now, cad has been widely used in electronic and electrical, scientific research, mechanical design, software development, robotics, clothing, publishing, factory automation, civil construction, geology, computer art and other fields.
Unigraphics NX of UG EDS Company is a product engineering solution, which provides digital modeling and verification means for users' product design and processing. Unigraphics NX provides a mature solution for users' virtual product design and process design needs. Unigraphics NX provides a brand-new product development model for designers and engineers, which can not only manipulate geometry, but more importantly, the team will be able to develop products according to engineering requirements. Unigraphics NX can effectively capture, utilize and * * enjoy knowledge in the whole process of digital engineering, which has been proved to bring strategic benefits to enterprises.
NX of UGS PLM enables enterprises to realize the goal of transforming to product life cycle management through a new generation of digital product development system. NX contains the most widely used integrated application suite in enterprises, which is used in the development process of product design, engineering and manufacturing.
Nowadays, the challenge facing the manufacturing industry is to strike a balance between the requirements of continuously reducing costs and increasing income and profits through technological innovation in product development. In order to truly support innovation, more alternative design schemes must be reviewed, and key decisions must be made earlier in the development process based on the knowledge gained from past experience.
NX is a new generation digital product development system of UGS PLM, which can drive product innovation through process change. NX is unique in its knowledge management foundation, which enables engineering professionals to promote innovation to create greater profits. NX can manage production and system performance knowledge, and confirm each design decision according to known standards.
NX is based on the successful experience of providing unparalleled solutions to customers, which can comprehensively improve the efficiency of the design process, cut costs and shorten the time to market. NX's success has once again been fully confirmed by focusing on technological innovation across the entire product life cycle. These goals enable NX to integrate the early process of product manufacturing from concept to production into a digital management and collaboration framework through unparalleled all-round product inspection applications and process automation tools.
Industrial design and style modeling;
NX provides a powerful solution for industrial design and style that promotes creativity and product technology innovation. Using NX modeling, industrial designers can quickly establish and improve complex product modeling, and use advanced rendering and visualization tools to meet the aesthetic requirements of design concepts to the greatest extent.
Product design:
NX includes the most powerful and extensive product design application modules in the world. NX has high-performance mechanical design and drawing functions, which provides high performance and flexibility for manufacturing design to meet the needs of customers in designing any complex products. NX is superior to general design tools, and has professional pipeline and circuit design systems, sheet metal modules, special plastic parts design modules and other professional applications required for industrial design.
Simulation, validation and optimization:
NX allows manufacturers to digitally simulate, validate and optimize products and their development processes. By using digital simulation performance early in the development cycle, manufacturers can improve product quality, while reducing or eliminating the expensive and time-consuming design and construction of physical prototypes and dependence on change cycles.
Tools:
NX tool application extends the design productivity and efficiency to the manufacturing field, and its solution is dynamically associated with the product model to ensure the accurate and timely development of production tools, workpiece fixtures and fixtures and complex molds.
Processing:
NX provides process-oriented machining solutions to simplify machining while optimizing speed and efficiency. With its omnipotent ability, NX machining solutions include advanced NC programming, tool path and machine simulation, post-processing, workshop documentation and process planning.
Orderly development environment:
NX product development solutions fully support all kinds of tools required by manufacturers, which can be used to manage processes and share product information with extended enterprises. NX seamlessly integrates with the complete suite of other UGS PLM solutions. These are supplements to the collaboration of CAD, CAM and CAE in controlled environment, product data management, data conversion, digital entity model and visualization.
UG's main customers include General Motors, General Electric, Ford, Boeing McDonnell Douglas, Lockheed, Rolls-Royce, Pratt & Whitney Engine, Nissan, Chrysler and the US military. Almost all aircraft engines and most automobile engines are designed with UG, which fully embodies the powerful strength of UG in high-end engineering field, especially in military field. Keep pace with CATIA in the high-end field.
UG's brother software:
1.Team Center is called the most powerful PLM software together with Dassault's Smarteam.
2.Postbuilder is a part of UG software and a powerful post-processor of CAM/CNC.
3.Nestran and Nestran of NASA belong to the same root and group, and it is a powerful CAE software for military industry and aerospace industry, mainly used to solve linear problems.
4.I-DEAS, high-end military software, used by Ford and Nissan, is often used in CAE field.
5. The mid-range design software SolidEdge is a common software besides Solidworks, and its strength is sheet metal.
6.Imagewre is a software for reverse modeling and automobile A-side modeling, and it is a market leader in this field.
UG's secondary development tool is very powerful, so it is necessary to introduce:
1.Open Grip provides the simplest interpretation language, similar to Lisp of AutoCAD, which can complete most functions of curve and solid CAD. The generated file can be called through the menu. The men file is developed by UI Styler, or by Open API(C language) or Open C++.
2.Open API, also called Open C, is a C language function library of UG, which puts functions with similar functions in the same one. H header file, as long as it is #include in. C file #, compile and generate a dll. This dll file can be called directly in three ways:
1) by. Men need to write in. Men's files.
2) Respond to the function call through the button in the dialog box. Dlg developed by UI Styler
3) Call by opening clamp function.
Open C is the most powerful secondary development tool, which can realize the secondary development of all UG functions such as sketch, 3D solid surface, product assembly, automobile module, mold module, knowledge fusion, CAM processing, finite element FEM, database operation, etc.
3.Open C++ is similar to Open C, except that the function library is in the form of C++ class library, which can be written and called by C process-oriented or C++ object-oriented methods. But the function is limited to CAD.
4.UI Styler is used to expand the secondary development of menu commands, dialog boxes and interfaces. Generated. Men,. Dlg can call the executable code written in the above secondary development language.
5. Tool language is a set of tool description language provided by UG, which is widely used in Genius equipment tool management and Postbuilder.
Generally, there is no need to modify the post-processor of CAM. Take Postbuilder as an example. In this cross-platform tool written in Java, there are machine tool type, spindle, machine tool axis, feed speed, tool description and so on. Are all done by this tool language generated by Java. Any visual modification in the Postbuilder window will automatically modify these tool languages. Experienced users or third parties can also modify these tools themselves.
6. In addition, you can also use VB, Java and other languages to achieve the same effect as the above-mentioned secondary development tools through various operations. Settings,. Template,. dat,。 dlg,。 Men files and databases in UG installation directory. This is also the strength of UG secondary development tools.