Whether in Europe, America or China, the informationization of many enterprises begins with CAD. The top managers of many enterprises have made up their minds to invest a lot of manpower and material resources in enterprise informatization only after seeing the great value of informatization in enterprises from CAD. CAD can be said to be a microcosm of the development of manufacturing informatization. In the past 50 years, with the continuous progress of CAD, enterprises are also developing. What is the development history of CAD? What are the development directions in the future, and how do enterprises choose so many CAD? I will take you into the world of CAD and discuss these problems one by one.

1. 1 From computer graphics to 2D CAD

Speaking of the development history of CAD, we have to talk about the development of computers. 1946: ENIAC (Electronic Digital Integrator and Computer) was born, which is the first real digital electronic computer. The development of ENIAC started at 1943 and was completed at 1946. The leaders are John W. Mochri and J. Presper eckert. This big guy weighs 30 tons, uses 18000 electron tubes, and has a power of 25 kilowatts, which is mainly used for ballistic calculation and the development of hydrogen bombs.

CAD: the epitome of manufacturing informatization

Since the appearance of computers, engineers and technicians hope that computers can not only perform operations of "addition, subtraction, multiplication, division or NAND", but also express and process graphics. Due to the technical limitations at that time, until the early 1960s, computers could only perform passive graphics processing.

In the early 1960s, computer graphics became a specialized subject and became more and more mature. At the same time, new ideas such as interactive technology and hierarchical storage symbol data structure are constantly put forward, which provide a theoretical basis for the application and development of CAD. At this time, specialized CAD equipment began to appear in the United States. At this time, CAD appears more as a substitute for sketchpad, and the concept of CAD is still in the stage of computer-aided drawing (or drawing), far from reaching the stage of "aided design".

CAD: the epitome of manufacturing informatization

In 1970s, the American company applicon took the lead in launching a complete CAD system. A commercial cad/cam system for small and medium enterprises came into being. At the end of 1970s, more than 65,438+02,000 cad workstations were installed in the United States, with more than 25,000 users.

CAD: the epitome of manufacturing informatization

In 1980s, with the rapid popularization of personal computers, CAD technology also developed rapidly. The epoch-making Autocad was born in 1982, and by 1985, it had sold 654.38+million sets. CAD has entered the stage of popularization. In the middle and late 1980s, a few domestic enterprises began to gradually apply CAD. However, due to the high price of computers at this time, a few computers in enterprises are generally only used as special calculations, so CAD is not popular in China, and more are folk enthusiasts.

In 1990s, with the maturity of windows series operating systems and the decline of computer prices, CAD began to step down from the altar. 199 1 year, State Councilor Song Jian put forward the slogan of "getting rid of charts", which officially kicked off the popularization and application of CAD in China. Because windows 95/98/NT operating system and workstation plus Unix operating system constitute the mainstream working platform of CAD system, the current CAD technology and system have good openness, and the graphical interface and graphical function are increasingly standardized.

In 1990s, when Ma Benteng was crowded with competitors, Autocad began to occupy the market rapidly with its good stability, excellent openness and graphical interface conforming to windows specifications. 1996 Autocad sold150,000 sets, becoming the "uncrowned king" in the field of 2D CAD in the world. So now many people mention CAD, which means Autocad. 1998, Autodesk released an epoch-making version of Autocad R 14, which is the first cad software that fully conforms to Windows 98. Its birth actually established the interface standards and format standards of CAD software on various windows platforms. Most of the interface and button styles of 2D CAD software we can see today are from Autocad R 14. This version is still used by many Autocad users.

However, the intellectual property protection system in China was not perfect at that time, and Autocad of most enterprises was pirated. Although the piracy problem of Autocad objectively makes it the most installed cad product in China enterprises, and helps many China enterprises realize the great charm of computer drawing for the first time, it also lays a curse for China manufacturing enterprises to face piracy infringement lawsuits frequently today.

At this time, driven by the policy, domestic CAD software manufacturers began to emerge in large numbers. Domestic cad manufacturers were divided into two camps from the beginning: CAD with completely independent intellectual property rights represented by Gaohua CAD, Huazheng Electronic Drawing Board, Daheng CAD and Mu Kai CAD, and value-added development CAD based on Autocad represented by Tianhe CAD, XTCAD and InteCAD.

Special mention should be made here of Huazheng Electronic Chart and Mu Kai CAD. Huazheng electronic chart, the predecessor of CAXA electronic chart, has become the domestic CAD with the largest installed capacity in domestic machinery industry. Mu Kai CAD is a brand-new interpretation of the connotation of CAD from the perspective of descriptive geometry and based on the usage habits of Chinese engineers. These two CAD models can be regarded as the epitome of China's struggle for independent property rights CAD in that era.

Because Autocad monopolizes more than 90% of the domestic mechanical cad market, CAD products with independent intellectual property rights are facing an insurmountable "gap", that is, compatibility with DWG format. Because it can't be saved as DWG drawings, there is data loss in reading AutoCAD files, and there are obstacles in communicating with AutoCAD user drawings, which makes domestic CAD lose a large number of customers. Up to now, although CAD with independent intellectual property rights has made a lot of efforts, due to Autodesk's intellectual property protection policy, CAD with independent intellectual property rights can only be compatible with the lower version of DWG file format, but not with the latest version of DWG format, which makes CAD with completely independent copyright criticized.

2 1 century, with China's accession to the WTO, China's manufacturing enterprises have increasingly frequent foreign exchanges. At the same time, in order to fulfill the commitment to protect intellectual property rights worldwide, China has begun to strengthen the management of software legalization from the government level. More and more enterprises began to legalize pirated AutoCAD software.

At this time, the "new generation" of independent intellectual property CAD represented by Zhongwang and Chen Hao began to leap onto the stage. This kind of two-dimensional CAD with IntelliCAD as the core helps enterprises solve copyright problems, and it is said to be fully compatible with DWG format. After them, many domestic CAD companies, including Mu Kaiyao Chuang and Wei Heng, chose to develop their own proprietary CAD software on IntelliCAD platform. At present, the independent property right CAD based on IntelliCAD kernel has become a great force that can compete with Autocad.

In fact, IntelliCAD is not a "new product", but has been living in the shadow of Autocad with a lot of fate. As early as 1994, American Softdesk company began to develop a set of CAD software: Phoenix, which claims to be 99% compatible with AutoCAD. 1996, Autodesk and Softdesk merged, but due to the restrictions of American antitrust law, Phoenix had to be sold before the merger. As a last resort, Softdesk sold Phoenix to VISIO for $6.7 million. 1998, VISIO released intelli CAD 98-now Intellicad98 was born.

At this time, with the great success of R 14 version, AutoCAD left all competitors including IntelliCAD far behind. IntelliCAD decided to seek a new business model after leaving Visio. Therefore, the organization of IntelliCAD Technology Alliance (ITC) was born. ITC adopts semi-public program code, and any company interested in Intellicad can spend money to obtain the modified program code and sell it publicly. However, all modifications must be made public to ITC, and IntelliCAD must be marked when publishing. The latest version of IntelliCAD claims to support DWG 2008.

IntelliCAD has been criticized for its many defects. Both Zhongwang and Chen Hao have made a lot of modifications to IntelliCAD, and it is said that more than 4,000 bugs have been modified. Therefore, the stability of products based on IntelliCAD platform depends on the technical level and investment of developers.

The sudden emergence of independent copyright CAD with Intellicad as the core makes the two-dimensional CAD market in China present a three-legged situation of Autocad, completely independent intellectual property CAD and independent copyright CAD with IntelliCAD as the core.

1.2 "Nuclear" War of 3D CAD

In fact, from the development history of CAD, CAD was not divided into "two-dimensional" and "three-dimensional" at first. From 1950s to 1960s, the development of computer graphics has advanced by leaps and bounds, and two-dimensional drawing and surface line modeling have made great achievements and formed recognized standards, so scientists turned their perspectives to solid modeling technology.

1968, Professor Norio Okino of Japan took the lead in introducing the concept of entity into three-dimensional geometric modeling, and presided over the development of TIPS system. Two-dimensional CAD and three-dimensional CAD "parted ways" from now on.

Time entered the 1970s, and the aircraft and automobile industries of the world's industrial powers flourished. During this period, a large number of free-form surfaces were encountered in aircraft and automobile manufacturing. The free-form surface designed at that time can only be approximately expressed by multi-section view and characteristic latitude. Due to the incompleteness of the three-view method, it often happens that after the design is completed, the samples made are very different from what the designer imagined, or even completely different. Designers can't guarantee whether the surface shape they designed can meet the requirements, so they often make sludge models in proportion as the basis for design review or scheme comparison. The slow and complicated production process has greatly delayed the research and development time of products, and the voice of updating design means is getting higher and higher.

From 65438 to 0972, Professor H.B.Voelcker of the University of Rochester in the United States began to develop PADL system. Starting from 1979, Volcker further combined with American industrial forces, developed the PADL-2.0 system with the support of the National Natural Science Foundation, and launched the trial version at 1982. At that time, Unigraphics (UGS for short, now the predecessor of Siemens PLM software), CALMA, Auto-Trol and AutoCAD 12 all used PADL2 as the entity modeling module of their own CAD/CAM commodity systems.

At that time, it was in the Cold War, and 3D CAD technology was closely protected as a technology to effectively improve a country's industrial capacity, especially in national defense industries such as aerospace. Only a few military enterprises have the conditions to develop and use this technology. For example, the CADAM system was developed with the support of Lochheed. General Electric Company (GE) developed the CALMA system. Boeing supports the development of CV system. National Aeronautics and Space Administration (NASA) supports the development of I-DEAS system; American McDonnell Douglas (MD) Company developed UG system; Dassault France developed CATIA system. ...

At the same time, some powerful automobile enterprises have begun to develop their own surface modeling software by using commercial 3D CAD technology. For example, Volkswagen develops the SURF system; Ford Motor Company developed PDGS system. The French Renault automobile company developed Euclid system. ...

Strictly speaking, the 3D CAD at this time is only designed to meet the needs of solving complex surface modeling, and it has not reached the real "entity".

At the same time, CAM and CAE technologies are also developing vigorously. Under the background of the Star Wars program at that time, with the support and cooperation of NASA, the American SDRC company developed many special analysis modules to reduce the huge space test cost. However, in CAE analysis, the biggest difficulty is that the surface model technology can only express the surface information of the car body, and it is difficult to accurately express other characteristics of the parts, such as mass, center of gravity and moment of inertia. So in 1979, SDRC released the world's first large-scale CAD/CAE software based entirely on solid modeling technology ──I-DEAS, and SDRC became famous for guiding the solid revolution of 3D CAD. However, due to the limitation of computer hardware conditions and entity algorithms at that time, the development of 3D entity model did not continue, and SDRC did not "open up the world". After more than 20 years, it was reluctantly acquired by EDS.

In addition to the limitation of hardware conditions, another important reason why many enterprises are unwilling to use 3D solid modeling is that the reliability of voxel combination of solid modeling under different algorithms is not completely consistent. So that when selling 3D CAD software at that time, the contract should indicate: "Our company will not bear legal responsibility for any quality accident losses caused by using this software".

1973, Ian Braid, a legend in the field of 3D CAD, graduated from Cambridge University. He cooperated with his tutor Charles Lang and classmate Allen Greer, hired Dutch Peter Wienmann as the marketing planner, founded Shape Data Company in 1974, developed the first generation of solid modeling commodity system Romulus in Fortran language, and put it on the market from 1978. Since then, the Parasolid kernel that has been influenced to this day was born.

198 1 year Evans &; Sutherland got the shape data. 1986, with the support of Ian Braid, began to develop the second generation solid modeling Parasolid system with American copyright. 1988 or so, UG bought Parasolid to replace PADL2. After more than 20 years of application, Parasolid has become one of the most stable general geometry development platforms in the current CAD system. So far, many experts and scholars in the field of CAD in the United States believe that Parasolid is the most important contribution made by the United States to the development of CAD in the world.

1986, American space technology companies began to develop a new generation of CAD general support platform, and they quickly reached a cooperation intention with Ian Braid. The CAD system TIGER, ACIS 1.0, developed based on Boeing Company 1980~ 1985, was launched in February,19X65438. ACIS is Ian Brad's classmate Allen Greer, and his mentor Charles Lang and Ian Brad use Solid as the prefix. 1June, 1993, Autodesk signed a contract with Spatial Company to adopt ACIS as the development platform of MDT, a three-dimensional mechanical design system. Since then, it has become the largest user of cargo information forecasting system.

On July 5th, 2000, French company dassault systemes signed a contract to acquire ACIS kernel for $265,438+$500,000 in cash. This means that CATIA, one of the world's largest installed 3D CAD software, will also adopt ACIS kernel.

At present, Parasolid kernel is mainly adopted by NX, Solidedge of Siemens PLM software and Solidworks of Dassault. ACIS is mainly adopted by MDT, Inventer under Autodesk and CATIA under Dassault. Three-dimensional CAD software with these two cores occupies more than 90% of the world market share of three-dimensional CAD software. The core algorithm (also called kernel) of 3D CAD has changed from a chaotic state of fragmentation to a competition between Parasolid and ACIS.

Careful readers may find that the above 3D CAD products lack a well-known 3D CAD product name-Pro/Engineer. First, introduce the birth history of Pro/Engineer and its "mother"-Parametric Technology Company (PTC).

1974, Samuel geisberg, a 37-year-old Soviet, came to the United States and worked for CV Company, which provided three-dimensional technology for Boeing Company. At that time, CV Company was the leading manufacturer of 3-D curved surface wireframe modeling, which was in full swing. Its power and arrogance not only prevented the popularization of I-DEAS, the first full three-dimensional solid modeling CAD software at that time, but also left the wisdom and talent of a group of mathematical geniuses like Samuel Gasberg nowhere to display.

Samuel Geisberg put forward a new solid modeling method: design modification based on features, full size constraints, full data association and size drive. But his idea was not adopted by CV Company. 1985, with the support of venture capitalists, he led his research team to leave CV Company and set up a parametric technology company-PTC was born. Two years later, PTC launched their full parametric 3D modeling software Pro/Engineer.

The idea of full parametric 3D modeling and Pro/Engineer have changed the history that the previous solid modeling software was not driven by size parameters, which is more in line with the designer's conception habit. As soon as it was launched, it attracted the attention of the whole world. In the past 20 years, today's 3D CAD software has adopted the modeling ideas based on features, full size constraints, full data association and size-driven design. Today, it has developed into a leader in the PLM field, with an annual income of more than $6,543.8+$0 billion.

1997165438+1October, PTC bought its "mother", CV Company, for US$ 262 million, and merged the product data management system Optegra of CV and the vast user market of CAD/CAM system CADDS5. CV Company finally paid the price for its arrogance.

If DEAS initiated the entity revolution of 3D CAD, then Pro/Engineer initiated the feature parameter revolution of 3D CAD.

2 development articles

1999, Dassault Systemes launched a brand-new CATIA V5, which changed the history that CATIA V4 only ran on UNIX platform and was completely developed on Windows platform. At this point, all high-end 3D CAD(CATIA, Pro/E, NX) have entered the Windows era, which has also triggered more intense competition in 3D CAD.

As soon as time entered the 2 1 century, a blockbuster was dropped in the field of 3D CAD. EDS acquired SDRC and merged with UGS. The new UGS (now renamed Siemens PLM software) has made a clear road map, which is to integrate the advantages of SDRC I-DEAS and UG to create a brand-new 3D CAD software-NX!

Maybe many people don't know that UG didn't have the navigation function when sketching until the last big version of UG 18, but in the NX era, it had a powerful navigation function from NX 1, which was the result of integrating I-DEAS. Of course, NX series has improved more than that compared with UG 18. In fact, NX has not fully digested the excellent design idea of I-DEAS.

PTC also released the latest version of Pro/Engineer-Wildfire in 2002. Compared with the previous version, the most significant improvement of Pro/E of Wildfire series is the interface. Anyone who knows more about the development history of Pro/E may know that before the birth of wildfire, all the operations of Pro/E were realized through progressive menus, and wildfire provided icon buttons for its loyal supporters. However, some enthusiasts think that the progressive operation menu is more efficient for users who are familiar with Pro/E, so up to now, Pro/Engineer wildfire has kept some progressive operation menus.

With the continuous maturity of technology and the increase of users, the prices of various 3D CAD software are also declining, which objectively promotes the rapid popularization of 3D CAD, and thus leads to the debate on whether 2D CAD will be eliminated.

In fact, 2D CAD is more convenient for communication, the automation degree of production and processing site is not very high, and there is a realistic demand for plane drawings, so it may not be a temporary thing for 2D CAD to quit the historical stage.

In this case, various CAD manufacturers have certain countermeasures.

Two-dimensional CAD manufacturers, represented by Autodesk, changed the style of focusing only on software platform development in the past and began to pay attention to industrial applications. Autodesk began to develop various industry versions by itself, and introduced mechanical and electrical versions one after another. Zhongwang Chen Hao also began to move to the machinery industry, and joined hands with Autocad value-added developers who had cooperated with AutoDesk in the past to start industry value-added development on IntelliCAD platform.

3 potential customers

3. One of the development directions of1:modeling without historical constraints.

PTC brings 3D CAD software into the era of feature-based, full-size constraint, full-data association and size-driven design. But everything has advantages and disadvantages. People who are used to 2D CAD will encounter a big obstacle when they start learning 3D CAD: modeling.

Modeling actually includes two aspects:

First of all, users must be familiar with the characteristics of 3D CAD and what modeling functions can be realized by these characteristics. Familiar with these, and then use various functions to build the model that users want. Usually, a part modeling will use from tens of thousands to tens of thousands of features. In order to manage these features and facilitate backtracking, most 3D CAD have such a "feature tree".

It is not enough to have features, but also to calculate the parameters needed for modeling, such as how much stretching and how deep the hole is. In the past, when doing two-dimensional design, many engineers used to draw pictures, especially complex surfaces, which were very enjoyable. In the era of three-dimensional CAD, because of the realization of full parameterization, it means that all graphics must be expressed by mathematical formulas and models, and engineers can no longer design by hand.

In many enterprises, 3D CAD has become the "coolest" thing that restricts engineers' whimsy, and some engineers even have to spend 1/3 time thinking about what features and parameters should be used to model in order to achieve the desired effect. Therefore, many engineers hope that 3D CAD is like a piece of mud, which can be freely kneaded into the desired shape without being limited by features and parameters.

This seemingly contradictory demand, in fact, many 3D CAD manufacturers have been working hard for it. The concept they advocate is called modeling without history, which translates into modeling without historical constraints. Most 3d CAD companies dedicated to modeling without historical constraints are small, including CoCreate, Kubotek USA, SpaceClaim, IronCAD, Think3… ..

Careful readers may have found that:

In 2004, IronCAD and CAXA announced the merger and reorganization, and the president of IronCAD was the president of CAXA America.

CoCreate was acquired by PTC for $250 million in 2007;

In 2008, Think3 and Exeter jointly established Beijing Exeter Information Technology Co., Ltd.;

Also in 2008, Siemens PLM software, the "big shot" in PLM field, released NX6 and SolidEdge2008 based on synchronous modeling technology, and the biggest selling point of these two products is what "modeling without historical constraints" advocates: models can be edited correctly no matter what time and data source.

Although Siemens PLM software is not the first manufacturer in the world to invent or commercialize the technology of "modeling without historical constraints", it is indisputable that Siemens PLM software is the first software manufacturer to fully integrate the technology of "modeling without historical constraints" into its own products and promote it globally.

Compared with Siemens PLM software, Dassault Systemes and PTC do not advertise that their CATIA and Pro/Engineer have applied modeling technology without historical constraints, but in fact, this technology can be seen more or less in their latest versions. For example, CATIA V6 and Pro/Engineer Windfire 5.0 both support the functions of editing and pasting models from any source and performing Boolean operations on original models.

It can be said that "modeling technology without historical constraints" has become a historical necessity from "undercurrent surging".

3.2 The second development direction: software is becoming more and more "green"

Nowadays, people pay more and more attention to the impact of products on the environment, and countries all over the world have also introduced various environmental protection laws and regulations to improve the market access threshold. From corporate shareholders to consumers, everyone is constantly improving the environmental awareness of products. Faced with all kinds of harsh environmental regulations, manufacturing enterprises must respond from the design link, so several major 3D CAD manufacturers began to provide customers with "green" design solutions.

A typical example is Solidworks, a subsidiary of dassault systemes Company.

In 2008, Solidworks cooperated with Gabi Software, the manufacturer of LCA (Life Cycle Assessment), with the code name "Sage", aiming at the perfect integration of Gabi and Solidworks.

Gabi Software's predecessor was IKP Institute of Stuttgart University in Germany, which organized a global environmental assessment organization-PE International for Gabi. Through experts distributed around the world, Gabi can quantify the environmental performance of materials, processes, products and infrastructure, including more than 65,438+000,000 impact modes. It can evaluate sustainability from different angles such as greenhouse gas, energy, the most significant environmental impact, life cycle cost and social impact.

On September/0/0, 2009, Solidworks released the research result of Sage project-SolidWorks 20 10. In this version, SolidWorks has added the environmental assessment module Sustainability, which can measure the environmental impact of products in the whole life cycle according to four factors: carbon emission, air acidification, water eutrophication and total energy consumption. For each of the above factors, the current value, baseline comparison with the original design and contribution percentage are displayed in the form of dashboard.

Because Solidworks 20 10 uses the same kernel as its brother CATIA V6, we have reason to believe that the sustainability module will probably become the "standard" of two 3D CAD softwares under Dassault Systemes in the future.

Compared with dassault systemes, the other two giants in the field of 3D CAD are very dramatic in dealing with the "green" challenge.

Synapsis Technology is a company that provides EMARS, which is a compliance management solution for materials, components and products. PTC Company collected it from June 5438 to February 2008, and released Windchill 9 integrated with EMARS in June 2009.

Siemens PLM software did not shy away from the relationship between Synapsis technology and PTC, and cooperated with it. In 2009, Teamcenter 8, which integrated some EMARS functions, was launched.

Faced with "green", PTC and Siemens PLM software, two competitors, reached an agreement, which is quite similar to Dassault Systemes on the other side of the ocean.

3.3 The third development direction: "Machine" and "Electricity" are getting closer and closer.

With the progress of the times, we will find fewer and fewer products around us, pure "mechanical" or pure "electronic" products. Even products classified as electronic products like mobile phones have mechanical parts. In the past, 3D CAD software for mechanical design and ECAD software for electronic circuit design were two different categories, and the information communication between them was very inconvenient, which greatly affected the design efficiency and quality of electromechanical hybrid products, so several major CAD manufacturers began to explore the road of electromechanical integration design.

In 2005, PTC acquired OHIO Design Automation in the field of ECAD, and took InterComm, a tool for enjoying PCB design data, as part of its PLM solution. In the later version of Pro/ENGINEER Wildfire 4.0, ECAD collaboration module was added, which made Pro/E have certain circuit design ability.

In April 2008, SolidWorks took Priware Limited, a former gold medal partner, into its pocket, and embedded its ECAD conversion tool CircuitWorks as a plug-in in SolidWorks2008SP4 after SP 4. With this plug-in, SolidWorks users can import the graphic information of circuit boards designed by other ECAD into SolidWorks model to verify the adaptability of circuit boards and mechanical parts.

Because EDA is very professional and special, objectively speaking, it is very difficult to realize mechanical and electronic design perfectly in a CAD software. But PTC and SolidWorks have made useful attempts in this respect and solved some practical problems in engineering design. With the progress of the times, we have reason to believe that mechatronics design will be an important development direction of CAD in the future.

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