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After more than forty years of development, CAD/CAM technology has made great progress. Currently, CAD/CAM is mainly run on workstations or microcomputer platforms. Although workstations offer superior performance and fast graphics processing speeds, their high cost limits the widespread adoption of CAD/CAM technology to some extent. With the emergence and popularity of Pentium chips and the Windows NT operating system, CAD/CAM software that could only run on workstations can now also be run on personal computers. Since the price of microcomputers is much lower than that of workstations, and their performance is not far inferior to that of mid-to-low-end workstations, moreover, the security of the Windows NT operating system has seen a significant improvement compared to operating systems such as DOS, Windows 3.x, and Windows 95/98. Therefore, the microcomputer platform creates excellent conditions for the widespread use of CAD. On this basis, CAD/CAM software manufacturers have launched a new round of competition. On the one hand, the renowned CAD/CAM software used on workstations (such as UG and CATIA) has been fully ported to microcomputer platforms, enabling microcomputers to achieve identical processing capabilities to those of workstation environments ； On the other hand, CAD/CAM software has broken free from the constraints of the traditional Unix environment and expanded extensively on the Windows platform. Processors above Pentium and the NT environment have become, or are becoming, the mainstream platforms for running and applying CAD/CAM software. The current status of CAD/CAM software is as follows: First, microcomputers are used as the development and application platforms. The characteristics of CAD/CAM software based on microcomputer platforms are as follows: 1. Use of the Windows environment – The use of the Windows NT operating system is a common feature of the new generation of microcomputer-based CAD/CAM software. Now, personal computers have the capability to compete with mid-to-low-end workstations, and combined with their low cost, this makes it possible to popularize CAD applications. The new generation of CAD/CAM software on the Windows platform generally adopts a typical Windows interface and operating conventions. Moreover, thanks to the widespread use of DDE and OLE technologies, these CAD/CAM applications can exchange data dynamically with other software on the Windows platform, as well as embed (or link) objects from other applications without leaving the CAD/CAM software. 2. Adoption of COM technology: COM (Component Object Model) is an important technology introduced internationally to improve software stability and development efficiency. All CAD/CAM software for the Windows platform available today makes use of COM technology to varying degrees. By using off-the-shelf components, software developers can avoid many of the tedious and difficult fundamental aspects of software development, thereby starting from a very high level and **reducing the time it takes to bring CAD software to market, which makes it easier to gain a competitive advantage. At the same time, the use of object-oriented technology enhances the maintainability and scalability of microcomputer CAD software. 3. Incorporating the advantages of Unix platform software: The CAD software for the new generation of microcomputer platforms fully draws on the best features of Unix workstation software. Excellent features such as parameter-driven design, feature-based modeling, dynamic navigation, two-dimensional and three-dimensional interrelation, the STEP standard, and dynamic graphic display have all been incorporated into microcomputer platform software. II. Implementation of PDM technology: With the spread of CAD technology, existing technical management systems are faced with significant challenges. Before the adoption of computer-aided design, various types of drawings, technical documents, process cards, production orders, change orders, purchase orders, cost calculation sheets, and material lists involved in the design, manufacturing processes, and management of products were all prepared, approved, classified, distributed, and archived manually, with all such materials being managed uniformly through a technical documentation room. Since the adoption of computer technology, the aforementioned product-related information has all become electronic data. Simply using computer technology to simulate the traditional manual data management methods often fails to fundamentally resolve the contradiction between advanced design and manufacturing techniques and outdated data management practices. To resolve this contradiction, PDM technology must be adopted. PDM (Product Data Management) is an advanced computer management system software that emerged from the need to manage CAD/CAM systems. It manages all the data throughout the entire lifecycle of the product. The product drawings designed and the process documents prepared by engineering and technical personnel based on market demands are only a part of the product data. In addition to managing the aforementioned data, a PDM system also needs to provide unified and effective management of related market demands, analyses, all changes throughout the design and manufacturing processes, user instructions, as well as after-sales service data. It can be seen that the product information managed by a PDM system involves various departments of an enterprise, such as product design, manufacturing processes, production, operations, and services. Therefore, the implementation of a PDM system is characterized by a wide range of involved aspects and a large volume of information processing. Implementing PDM technology enables parallel engineering, improves product design efficiency, supports total quality management, and achieves a balance among people, processes, and technology. Therefore, it can bring huge benefits to businesses. The implementation of PDM technology is different from that of CAD/CAM technology; the former adjusts the enterprise’s management model. Transitioning from the traditional manual management approach to a computer-based PDM management system requires taking into account both the existing management practices and the needs for information integration. Due to differences in aspects such as the enterprise’s technical environment, management level, and corporate culture, the PDM implementation process varies from one enterprise to another. Only by gaining a thorough understanding of the enterprise’s computer environment, business processes, and the overall objectives of PDM, and by conducting a comprehensive analysis of the enterprise’s detailed requirements for PDM products, can the most suitable PDM products and solutions for the enterprise’s development be selected. The current mainstream international PDM products include UG’s IMAN and SDRC’s Metaphase, while domestic PDM products include Tsinghua Tongfang PDM and Wuhan Tianyu PDM. III. Research and Application of Modern Integrated Manufacturing Systems (CIMS) Dr. S. Harrington of the United States first introduced the concept of CIM (Computer Integrated Manufacturing) in his book \"Computer Integrated Manufacturing\" in 1973. Its essence is to use computers to systematically integrate various manufacturing-related technical systems within a company, thereby enhancing the company’s ability to compete in the market. This concept emphasizes two aspects: (1) the various production stages of a company are inseparable and require unified planning and organization. (2) The product manufacturing process is essentially a process of information collection, transmission, and processing. CIM is an advanced concept, but due to the limitations of technology at that time, it was not until the early 1980s that this concept gained attention and was adopted in the manufacturing sector. Over the past decade or so, driven by market competition and advancements in related technologies, CIM has been continuously enriched, improved, and developed in practice. Starting from this concept, through research and practice in information integration, process integration, and enterprise integration, we proposed the concept of the Contemporary Integrated Manufacturing System (CIMS). In March 1986, our country launched the 863/CIMS program, thereby beginning comprehensive research and implementation of CIMS. The core of the thematic research and implementation technologies for 863/CIMS is modern integrated manufacturing, wherein integration is divided into three stages: information integration, process integration (such as parallel engineering), and enterprise integration (such as agile manufacturing). Next, we will briefly introduce these three types of integration one by one. 1. Information integration: Achieving accurate and rapid sharing and exchange of information within a company is the first issue that must be addressed in order to improve the company’s technical and managerial capabilities. Information integration is effective in enhancing a company’s market competitiveness, but the methods used to implement it remain rather outdated to this day. This results in a long development cycle for enterprise CIMS application projects, and it is difficult to ensure quality. Therefore, information integration will remain a key aspect of enterprise informatization in the future, as well as the foundation for implementing technologies such as parallel engineering. In our country, CIMS application projects that focus on information integration will remain an inevitable part of the informatization process for most enterprises in the future. 2. Process integration: The traditional design and development processes for sequential tasks often lead to repetitions during product development, resulting in longer development cycles and increased costs. By transforming as many of the sequential processes in product design as possible into parallel engineering, and by taking into account the manufacturability and assembly feasibility of subsequent steps during the design phase, repetitions can be reduced and development time shortened. Parallel engineering is an advanced manufacturing model based on this concept. 3. Enterprise integration: To enhance their market competitiveness, enterprises must address the new realities of global manufacturing and make full use of global manufacturing resources in order to respond to market demands in a better, faster, and more cost-effective manner; this is where agile manufacturing comes from. The organizational form of agile manufacturing is the establishment of dynamic alliances between enterprises for a specific product, namely so-called virtual enterprises. A company’s ability to form alliances continuously is one of the signs of its agility. The CAD/CAM software that is popular both domestically and internationally today; after decades of development, CAD/CAM technology has gone through various stages such as the mainframe era, minicomputer era, workstation era, and personal computer era, with popular CAD/CAM software existing in each of these eras. Today, CAD/CAM software for workstations and microcomputer platforms has taken precedence, and a number of high-quality, popular commercial software products have emerged. Next, we will introduce some popular software both domestically and internationally. I. Foreign software 1. Unigraphics (UG) UG is the flagship product of Unigraphics Solutions Corporation. For the first time, the company broke away from the traditional CAD/CAM approach to provide users with a comprehensive product modeling system. In UG, the advanced parametric and variational techniques are combined with traditional solid, wireframe, and surface functions; this combination has proven to be highly effective and is adopted by most CAD/CAM software manufacturers. UG was first applied by the American McDonnell Aircraft Company. It is software that has evolved from functions such as 2D drawing, CNC machining programming, and surface modeling. In the early 1990s, General Motors in the United States selected UG as the company-wide leading system for CAD/CAE/CAM/CIM, which further promoted the development of UG. In October 1997, Unigraphics Solutions signed a contract with Intergraph; the latter’s mechanical CAD products were integrated, and the desktop version of SOLIDEDGE software was brought under the Parasolid platform. This has resulted in a relatively comprehensive enterprise-level CAD/CAE/CAM/PDM integration system that ranges from the lower-end to the higher-end versions, including both Unix workstation versions and Windows NT desktop versions. 2. SOLIDEDGE SOLIDEDGE is a true Windows software. It does not involve simply migrating workstation software to the Windows platform; rather, it makes full use of Windows’ advanced technologies based on the Component Object Model (COM) to rewrite the code. SOLIDEDGE is compatible with Microsoft Office and Windows’ OLE technology, which allows designers to use word processing, spreadsheet applications, database functions, etc., under Windows while working with CAD systems. SOLIDEDGE features a user-friendly interface that utilizes an interface technology called SmartRibbon. By pressing a command button, users can see the specific details and step-by-step instructions for that command on the SmartRibbon, while the status bar informs them of what to do next. SOLIDEDGE is a next-generation mechanical design CAD system based on parametric and feature-based solid modeling; it is a solid modeling system specifically developed for designers, offering ease of understanding and use. 3. AutoCAD AutoCAD is the flagship product of Autodesk. Autodesk is the fourth-largest PC software company in the world. In the CAD/CAE/CAM industry, the company is currently the software provider with the largest number of users worldwide, as well as the largest PC-based CAD, animation, and visualization software company globally. Autodesk’s software products are widely used in major fields such as mechanical design, architectural design, film production, video game development, and Web data development. AutoCAD is the most popular 2D drawing software today, and it has a large user base in the field of 2D drawing. AutoCAD has powerful 2D functions such as drawing, editing, creating cross-sections and patterns, dimensioning, and secondary development, as well as some 3D functions. AutoCAD provides AutoLISP, ADS, and ARX as tools for secondary development. In many practical application fields (such as machinery, construction, and electronics), some software developers have developed numerous applications tailored for real-world use based on AutoCAD. Currently, Autodesk has released AutoCAD 2000, which is equivalent to AutoCAD R15. 4. MDT MDT is a 3D mechanical CAD system developed by Autodesk for PC platforms. It is based on 3D design and integrates various functions such as design, analysis, manufacturing, and document management ； It provides users with integrated solutions from design to manufacturing. The main functional features of MDT are as follows: (1) Feature-based parametric solid modeling. Users can conveniently create complex 3D solid models, and they can edit and modify these models flexibly. (2) Surface modeling based on NURBS enables the creation of various complex surfaces to meet the demands for such surfaces in areas like mold design. (3) It is possible to carry out the large-scale assembly of hundreds or even thousands of parts quite conveniently. (4) MDT provides associated drawing and sketching functions, offering a two-way connection between the complete model and the drawings. The launch of this software was well received by users across the board. To date, a total of 70,000 units have been sold worldwide, with nearly 1,000 units sold in the domestic market. Since this software, like AutoCAD, was developed by Autodesk, the two work seamlessly together, allowing users to easily convert from 3D to 2D. MDT offers a good option for AutoCAD users to upgrade to 3D. 5. SolidWorks: SolidWorks is a Windows-based mechanical design software developed by Bioinfo International Co., Ltd. BioInfo Company is a specialized information and high-speed technology services firm that remains in line with the international CAD/CAE/CAM/PDM market in terms of information and technology. The \"Windows-based CAD/CAE/CAM/PDM desktop integration system\" promoted by this company is an integration of various applications based on Windows and centered around SolidWorks, including structural analysis, motion analysis, engineering data management, and CNC machining – providing Chinese enterprises with a solution they have long desired. SolidWorks is a newcomer among parametric feature-based modeling software versions for microcomputers. It is designed to provide mechanical designers with practical solid modeling functions that offer a more user-friendly interface and a more accessible operating environment, at a cost that is 1/4 to 1/5 of that of the corresponding workstation version of this software. SolidWorks is a fully parametric feature-based modeling software based on the Windows platform; it enables easy creation of complex 3D part models, complex assemblies, and the generation of engineering drawings. The graphical interface is user-friendly, allowing users to get started quickly (Figure 2). This software can be used in the design and production preparation of mechanical products featuring regular geometric shapes, and it comes at a moderate price. 6. Cimatron: The CimatronCAD/CAM system is a CAD/CAM/PDM product developed by the Israeli company Cimatron; it was one of the first systems to offer full 3D CAD/CAM functions on microcomputer platforms. The system offers a relatively flexible user interface, excellent 3D modeling and engineering drawing capabilities, comprehensive CNC machining functions, various general and specialized data interfaces, as well as integrated product data management. Since it entered the market in the 1980s, the CimatronCAD/CAM system has been very popular in the international mold manufacturing industry. In recent years, in order to develop in the field of design and manufacturing, Cimatron has focused on adding many functional modules suitable for design, releasing new versions every year, and its market share has grown rapidly. In 1994, Beijing Aerospace Computer Software Co., Ltd. (BACS) began to promote the Cimatron software in China, and starting from version 8, it was localized in Chinese to meet the needs of technical personnel at various levels in domestic enterprises. Users come from fields such as machinery, railways, scientific research, and education; over 200 units have been sold to date, indicating promising market prospects. 7. Pro/Engineer: The Pro/Engineer system is a product of Parametric Technology Corporation (PTC). The concepts of a single database, parameterization, feature-based design, and full relevance proposed by PTC have transformed traditional ideas in mechanical CAD/CAE/CAM; these innovative concepts have become the new standards in the field of mechanical CAD/CAE/CAM worldwide. The third-generation mechanical CAD/CAE/CAM product developed using this concept, the Pro/Engineer software, integrates the entire process from design to production, enabling all users to work on the design and manufacturing of the same product simultaneously, thus realizing what is known as concurrent engineering. The main functions of the Pro/Engineer system are as follows: (1) True full inter Relevance, with any changes made in one place automatically being reflected in all related areas. (2) Possess the capability to truly manage concurrent processes and implement parallel engineering. (3) It has a powerful assembly function that enables the designer’s intentions to be maintained at all times. (4) It is easy to use and can greatly improve design efficiency. The user interface of the Pro/Engineer system is simple and intuitive, aligning with the design thinking and habits of engineers. The entire system is built on a unified database, featuring a complete and consistent model. Pro/Engineer is installed on workstations; the system is independent of hardware, making it easy to transfer. 8. I-DEAS I-DEAS is a CAD/CAM software developed by the American company SDRC. The company is a internationally renowned firm in the field of mechanical CAD/CAE/CAM, enjoying a high reputation worldwide. Many well-known companies abroad, such as Boeing, Sony, Samsung, Hyundai, Ford, and others, are all major clients and partners of SDRC. The I-DEAS MasterSeries 5 was first unveiled in the United States on June 20 this year, attracting widespread attention. It is a highly integrated CAD/CAE/CAM software system. It helps engineers to carry out the entire product development process – from product design, simulation analysis, testing to CNC machining – within a single digital model with extremely high efficiency. I-DEAS is a widely used large-scale CAD/CAE/CAM software among manufacturing users around the world. I-DEAS has long been at the forefront of the world in terms of CAD/CAE integration technology, and the software includes advanced analysis functions such as structural analysis, thermal analysis, optimization design, and durability analysis that truly enhance product performance. SDRC is also the world’s largest manufacturer of professional CAM software. I-DEASCAMAND is the top product in the CAM industry. I-DEASCAMAND can conveniently simulate the movement of tools and machine tools, enabling processing from simple 2-axis and 2.5-axis operations to highly complex workpiece surfaces using 7-axis 5-link motion, as well as automating and optimizing the CNC machining process. II. Domestic software 1. Gaohua CAD Gaohua CAD is a CAD product developed by Beijing Gaohua Computer Co., Ltd. The company was jointly established by Tsinghua University and Guangdong Kelon (Rongsheng) Group; it is a high-tech enterprise specialized in the research, development, promotion, application, sales, and service of CAD/CAM/PDM/MIS integrated systems. The company works closely with the **CAD Support Software Engineering Center**, adhering to the development path of a domestic software industry with independent intellectual property rights. With the commitment that \"the needs of users are our own needs,\" it has taken promising steps forward in transforming scientific research achievements into commercial products. Gaohua’s CAD product line includes the computer-aided drafting support system GHDrafting, the mechanical design and drafting system GHMDS, the process design system GHCAPP, the 3D geometric modeling system GHGEMS, the product data management system GHPDMS, and the automatic CNC programming system GHCAM. Among them, GHMDS is a CAD/CAE/CAM integrated system based on parametric design, featuring functional modules such as full-process navigation, graphic drawing, bill of materials processing, fully constrained parametric design, parametric pixel assembly, dimensioning, standard part library, and image editing. GHGEMS5.0 won first place in the second national evaluation of CAD support software with independent copyright. 2. CAXA Electronic Drawing Board and CAXA-ME Manufacturing Engineer: The developers and sellers of the CAXA Electronic Drawing Board and CAXA-ME Manufacturing Engineer software are Beijing Beihang Haier Software Co., Ltd. (formerly the Huazheng Software Research Institute of Beihang University). The company is a specialized firm that deals with CAD/CAE/CAM software and engineering services. CAXA Electronic Drawing Board is a set of efficient, user-friendly, and intelligent general-purpose Chinese design and drafting software. It enables designers to create part drawings, assembly diagrams, process charts, and packaging designs, and it is suitable for all applications that require 2D drawing. This software allows designers to focus on their creative ideas, eliminating the need for traditional drawing boards, and thus meeting the requirements of modern enterprises for fast design, drafting, and electronic data management. CAXA-ME is a self-developed CAD/CAM software for the machinery manufacturing industry, featuring a Chinese interface and the ability to handle complex 3D surfaces. CAXA Manufacturing Engineer version 1.0 was released in 1996, CAXA-ME version 2.0 was launched in March 1998, and CAXA-ME 2000 has also been released. 3. GS-CAD98 GS-CAD98 is a feature-based parametric modeling system developed by Zhejiang Datian Electronic Information Engineering Co., Ltd. The company is a high-tech research, development, and application enterprise jointly established in Hangzhou by the **Science and Technology Commission’s High-Tech Research and Development Center, Zhejiang University, and the CAD/CAM Center of China National Space Administration. Datian Company integrates software development, engineering applications, information system integration, and the sales of computer-related products. It is a high-tech company specialized in the development, application, sales, and service of CAD/CAPP/CAM engineering databases as well as MIS/OA systems. GS-CAD98 is a 3D CAD system with entirely independent copyright, based on microcomputers, and running on the Chinese Windows95/NT platform. This software was developed on the basis of achievements from major research projects and the development of products related to the 863/CIMS program themes, with reference to the user interface style and key functions of SolidWorks. It enables full interconnection throughout the process of 3D part design, assembly design, and engineering drawing generation; changes made in any module are automatically reflected in the other modules as well. 4. Lonicera system: The Lonicera system is a CAD/CAM system based on the STEP standard, developed by Guangzhou Hongdi Technology Co., Ltd. This system is the latest research achievement of the **Science and Technology Commission’s 863/CIMS project during the Ninth Five-Year Plan period. This software is primarily used in the design and manufacturing of mechanical products, enabling integration of design and manufacturing as well as automation. This software starts from a high standard, using the highest international standard in manufacturing, ISO-10303 (STEP), as the basis for its system design. This software employs object-oriented technology, utilizing advanced entity modeling, parametric feature modeling, integration of 2D and 3D elements, as well as the SDAI standard data access interface. It offers functions such as mechanical product design, process planning, and automatic generation of CNC machining programs. It also features various standard data interfaces such as STEP and DXF, and supports Product Data Management (PDM). The current series of products in the honeysuckle system include: the mechanical design platform MDA, the numerical control programming system NCP, the product data management system PDS, and the process design tool MPP. The mechanical design platform MDA (Mechanical Design Assistant) is one of the Honeysuckle series of software; it is an integrated 2D and 3D design system. Currently, MDA version 1.7 is available on the market, and MDA version 99 has also been released. "Honeysuckle “MDA was the first in China to be commercialized, posing a strong challenge to foreign 3D CAD software. 5. KaiMu CAD: KaiMu CAD is a CAD and drawing management software with independent intellectual property rights, developed by the School of Mechanical Engineering at Huazhong University of Science and Technology. It is based on a microcomputer platform, tailored to practical engineering needs, and simulates the way humans think when designing and drawing. It is easy to use, and its efficiency for mechanical drawing is much higher than that of AutoCAD. Kaimu CAD supports various types of geometric constraints as well as simultaneous control of multiple views. It features local parameterization and is capable of handling situations of over-constraint and under-constraint in design. Kaimu CAD achieves the integration of CAD, CAPP, and CAM; it suits the working habits of designers in China and is one of the key products promoted for CAD application projects across the country.