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History of CAD software

From Wikipedia, the free encyclopedia

Computer-aided design is the use of computers to aid in the creation, modification, analysis, or optimization of a design. Designers have used computers for calculations since their invention.[1][2][3][4] CAD software was popularized and innovated in the 1960s, although various developments were made between the mid-1940s and 1950s. Digital computers were used in power system analysis or optimization as early as proto-"Whirlwind" in 1949. Circuit[5] design theory or power network methodology was algebraic, symbolic, and often vector-based.

History

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Historical, mathematical, and technological foundations

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The conceptual roots of computer-aided design (CAD) can be traced back to Euclid of Alexandria (c. 350 BC), whose geometric postulates provided the theoretical basis for modern CAD systems. The formalization of Euclidean geometry enabled the development of algorithms for graphical representation and product modeling, which remain fundamental to CAD software.[6].

1940s

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From the late 1940s—following the introduction of the first operational computers at the universities of Manchester and Cambridge in 1948–1949—the use of computers rapidly expanded from scientific research into industrial applications. As early as 1953, Boeing began acquiring numerically controlled (NC) machine tools, paving the way for the practical use of computers in manufacturing and prototyping. This technological context—characterized by early memory systems, magnetic tape storage, and mechanical input/output devices—together with the growing adoption of NC machines, provided the material foundation for the emergence of CAD and CAM systems.[7]

1940s–1950s

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Between the mid-1940s and 1950s, various developments were made in computer software. Some of these developments include servo-motors controlled by generated pulse (1949), a digital computer with built-in operations to automatically coordinate transforms to compute radar related vectors (1951), and the graphic mathematical process of forming a shape with a digital machine tool (1952).[8]

In 1953, MIT researcher Douglas T. Ross saw the "interactive display equipment" being used by radar operators, believing it would be exactly what his SAGE-related data reduction group needed. Ross and the other researchers from the Massachusetts Institute of Technology Lincoln Laboratory were the sole users of the complex display systems installed for the pre-SAGE Cape Cod system. Ross claimed in an interview that they "used it for their own personal workstation."[9] The designers of these early computers built utility programs to ensure programmers could debug software, using flowcharts on a display scope, with logical switches that could be opened and closed during the debugging session. They found that they could create electronic symbols and geometric figures to create simple circuit diagrams and flowcharts.[10] These programs also enabled objects to be reproduced at will; it also was possible to change their orientation, linkage (flux, mechanical, lexical scoping), or scale. This presented numerous possibilities to them.

Ross coined the term computer-aided design (CAD) in 1959.[11][12]

1960s

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Early example of electronic CAD depicting transistor increasingly resembling point-contact transistor, from Sutherland's 1963 dissertation.

The invention of the 3D CAD/CAM is often attributed to French engineer Pierre Bézier (Arts et Métiers ParisTech, Renault). Between 1966 and 1968, after his mathematical work concerning surfaces, he developed UNISURF to ease the design of parts and tools for the automotive industry. UNISURF then became the working base for the following generations of CAD software.

In parallel, French carmaker Citroen had developed its design system SPAC (system de programmatic automatique Citroen) as part of its CAD/CAM solution SADUSCA (aid systems for the defining and the machining of bodywork surfaces), both based on the 1959 mathematical works of Paul de Casteljau. In 1968, it used an IBM 360-40, then 360-65 for batch jobs, but already had a graphical interface with an IBM 2250 prototype. [13] [14]

However, CAD may have been in use earlier at Boeing, having been used to help design the outer surface of Boeing's 727 airplane (which rolled out in 1962).[15] Based on his human factors cockpit drawings, William Fetter from Boeing coined the term "computer graphic" in 1960.[16] A computer graphics department was established in 1962, and by 1965 had begun to make movies by computer.[15]

In the 1960s, technological developments in the industries of aircraft, automotive, industrial control, and electronics provided advancements in the fields of three-dimensional surface construction, NC programming, and design analysis. Most of these developments were independent of one another and often not published until much later. Some of the mathematical description work on curves was developed in the early 1940s by Robert Issac Newton.[citation needed] In his 1957 novel The Door into Summer, Robert A. Heinlein hinted at the possibility of a robotic Drafting Dan. However, more substantial work on polynomial curves and sculptured surface was done by mathematician Paul de Casteljau from Citroen; Pierre Bézier from Renault; Steven Anson Coons from MIT; James Ferguson from Boeing; Carl de Boor, George David Birkhoff and Garibedian from GM in the 1960s; and W. Gordon and R. Riesenfeld from GM in the 1970s.

The development of the Sketchpad system at MIT[17][18] by Ivan Sutherland, who later created a graphics technology company with David Evans, was a turning point.[17] The distinctive feature of Sketchpad was that it allowed a human to interact with a computer graphically; the design can be fed into the computer by drawing on a cathode ray tube (CRT) computer display (monitor) with a light pen. In effect, this feature of Sketchpad was a prototype for a graphical user interface, an indispensable feature of modern CAD. In 1963, under doctoral adviser Claude Shannon, Sutherland presented his PhD thesis paper, Sketchpad: A Man-Machine Graphical Communication System, at a Joint Computer Conference. In his paper, he said:[19]

For drawings where motion of the drawing or analysis of a drawn problem is of value to the user, Sketchpad excels. For highly repetitive drawings or drawings where accuracy is required, Sketchpad is sufficiently faster than conventional techniques to be worthwhile. For drawings which merely communicate with shops, it is probably better to use conventional paper and pencil.

Over time, efforts would be directed toward the goal of having the designers' drawings communicate not just with shops, but also with the shop tool itself; however, it was a long time before this goal was achieved.

The first commercial applications of CAD were in large companies within the automotive and aerospace industries, as well as in electronics. This was because only large corporations could afford the computers capable of performing the necessary calculations. Notable company projects included a joint project between Patrick J. Hanratty from GM and Sam Matsa, Doug Ross's MIT APT research assistant from IBM, to develop a prototype system for design engineers, DAC-1 (Design Augmented by Computer) 1964, Lockheed projects, Bell GRAPHIC 1, and Renault.

One of the most influential events in the development of CAD was the founding of Manufacturing and Consulting Services Inc. (MCS) in 1971 by Patrick J. Hanratty,[20] who wrote the system Automated Drafting And Machining (ADAM), but more importantly supplied code to companies such as McDonnell Douglas (Unigraphics), Computervision (CADDS), Calma, Gerber, Autotrol, and Control Data.

As computers became more affordable, the application of CAD gradually expanded into new areas. The development of CAD software for personal desktop computers was the impetus for almost universal application in all areas of construction.

1970s

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Other notable events in the 1960s and 1970s include the foundation of CAD systems United Computing, Intergraph, IBM, and Intergraph IGDS in 1974 (which led to Bentley Systems MicroStation in 1984), as well as the Applicon in 1969 and commercial CAD systems from Japanese manufacturers Seiko and Zuken during the 1970s.[21]

CAD implementations have evolved dramatically since this early development. Initially, with 3D in the 1970s, CAD was typically limited to producing drawings similar to hand-drafted drawings. Advances in programming and computer hardware,[22][23] most notably solid modeling in the 1980s, have allowed more versatile applications of computers in design activities.

A Computervision Designer CAD system on display at an exhibition in 1978, representative of early commercial CAD systems.

During the 1970s, computer-aided design (CAD) software began to move beyond academic research and into commercial use. At the beginning of the decade, most CAD programs were developed internally by large automotive and aerospace companies, often in collaboration with universities. Major in-house developers included Ford (PDGS), General Motors (CADANCE), Mercedes-Benz (SYRCO), Nissan (CAD-I, 1977), Toyota (TINCA, 1973; CADETT, 1979), as well as Lockheed (CADAM), McDonnell Douglas (CADD), and Northrop (NCAD). Most systems were still two-dimensional (2D), replacing manual drafting and offering advantages such as reduced errors and improved reuse of drawings. Throughout the 1970s, CAD development focused primarily on automating 2D drafting.[24]

These systems allowed users to draw lines and circles on screen, requiring operators to combine drafting skills with programming knowledge.[24] Companies such as United Computing, Intergraph, and IBM developed significant applications, although they were constrained by the limited computing power of the available hardware.[24] CADAM, developed by Lockheed, became one of the most well-known programs of this period and later served as the foundation for CATIA, developed by Avions Marcel Dassault starting in 1977, which remains one of the most widely used CAD software packages today.[25]

Interest in three-dimensional (3D) CAD increased, particularly in the complex modeling of surfaces. The doctoral dissertation of K. Versprille (1975) and the work of R. F. Riesenfeld established foundational principles for 3D curve and surface modeling. The first solid modeling program, SynthaVision (1972), was originally conceived for nuclear analysis but anticipated the constructive solid geometry (CSG) structures later used in CAD software. Research in solid modeling continued along different approaches: CSG, developed by Herb Voelcker (PADL, 1978), and boundary representation (B-rep), introduced by Ian Braid within Charles Lang’s research group (BUILD, 1978), the first complete implementation of B-rep. Unigraphics incorporated 3D systems from its early versions, although double-precision support was not available until 1979.[24][25]

The increasing power of computers and the availability of affordable minicomputers with graphical terminals made CAD more accessible to engineers. Toward the end of the decade, a commercial CAD software market emerged, driving the creation of interoperability standards such as IGES (Initial Graphics Exchange Specification, 1979–1980), which enabled the exchange of 3D data between different systems. Numerous CAD software vendors were founded during this period, including M&S Computing (1970, later Intergraph) and MCS (1971), which released ADAM (1972), quickly adopted by other manufacturers. Major commercial CAD systems included Auto-Draft, Calma, CADDS, CADAM, IGDS, and Unigraphics. The CAD market grew from less than US$25 million in 1970 to approximately US$1 billion in 1979, with Auto-trol becoming the first CAD vendor to go public. The decade saw major advances in geometric algorithms and 3D modeling, while developments in hardware, high-level programming languages (such as C), simpler operating systems (notably UNIX), and the emergence of desktop graphics computers laid the groundwork for the subsequent workstation-based CAD era.[25]

1980s

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3D rendering of spoons in CAD software
Historical use of CAD software in 1980 on a PDP-11/70 to visualize the design of the M1 Abrams tank.
Historic CAD system (Dubied DUCAD-II on a Cromemco CS-2H) used in industrial applications in 1983.
Historic advertisement for AutoCAD 2.6 from 1987, illustrating CAD usage during the 1980s.

In 1981, the key products were the solid modeling packages—Romulus (ShapeData) and Uni-Solid (Unigraphics) based on PADL-2—and the surface modeler CATIA (Dassault Systèmes). Autodesk was founded in 1982 by John Walker, which led to the two-dimensional system AutoCAD.[26] The next milestone was the release of Pro/ENGINEER in 1987, which heralded greater usage of feature-based modeling methods and parametric linking of the parameters of features; this marked the introduction of parametric modeling.[27]

During the 1980s, the computer-aided design (CAD) sector transitioned from a research-oriented activity into a highly competitive industry, driven by rapid advances in both hardware and software. At the beginning of the decade, Digital Equipment Corporation (DEC) VAX minicomputers dominated engineering computing; systems such as the MicroVAX offered high performance at reduced cost and footprint, foreshadowing the workstation era. In parallel, specialized CAD companies emerged or consolidated their positions: Intergraph (formerly M&S Computing) introduced the InterAct and InterPro systems, Hewlett-Packard developed the PE software, Dassault Systèmes introduced CATIA (marketed by IBM), and General Electric acquired CALMA.[28]

The emergence of UNIX-based workstations—initiated by Apollo in 1980 and followed by Sun Microsystems and Silicon Graphics—profoundly transformed the CAD market by offering open, relatively affordable, and powerful platforms capable of supporting advanced CAD applications. Traditional mainframe and minicomputer manufacturers (including IBM, DEC, Burroughs, and Unisys) struggled to compete with this new generation of machines. In the personal computer segment, IBM introduced the IBM PC in 1981, followed by Autodesk’s release of AutoCAD in 1982, Adra Systems’ CADRA, Bentley’s MicroStation, CADKEY, and, in the Macintosh ecosystem, MiniCAD. However, until the 1990s, limitations in graphics and computational power prevented PCs from competing with workstations in 3D CAD.[28]

The 1980s also saw the emergence of CAM systems for production automation and CAE software for complex engineering analysis.[24] In 1981, Unigraphics released Uni-Solids, the first solid modeling system based on PADL-2.[24] At the same time, the spread of personal computers benefited Autodesk, founded by John Walker in 1982, which established AutoCAD as the de facto standard for 2D drafting and later for wireframe 3D modeling.[24] CADKEY gained prominence as an alternative for 3D applications.[24]

During the second half of the decade, CAD development shifted decisively toward solid modeling and full 3D design. Pioneering tools included UniSolids from Unigraphics, the Romulus kernel developed by Shape Data (later acquired by Evans & Sutherland), and its successor Romulus-D, the first 3D CAD system to support distributed configuration management. Feature-based parametric modeling emerged in the mid-1980s, fundamentally transforming the role of CAD in product design.[24] In 1984, the PDES initiative was launched to define new data exchange standards, while Dassault released CATIA V2 and Matra Datavision introduced Euclid-IS. By 1985, the market appeared relatively stable and was dominated by Computervision, GE/CALMA, Applicon, Intergraph, McDonnell Douglas/Unigraphics, and IBM/CATIA. The entry of Parametric Technology Corporation (PTC) with parametric modeling solutions introduced a disruptive competitive pressure that would significantly reshape the industry.[28]

The CAD software industry experienced rapid expansion during the late 1980s, supported by declining hardware and maintenance costs. Early in the decade, leading vendors—including Computervision, Intergraph, McDonnell Douglas (Unigraphics), GE/CALMA, IBM/Dassault (CADAM and CATIA), and SDRC (I-DEAS)—operated in a consolidated, high-price market and initially showed limited responsiveness to emerging competitors. At the same time, major aerospace and automotive companies (such as Boeing, General Motors, and McDonnell Douglas) gradually abandoned internally developed CAD systems in favor of commercial solutions, significantly expanding the overall market.[29]

A major turning point occurred in 1987 with the release of Pro/Engineer by Parametric Technology Corporation, the first 3D CAD system fully based on solid models and feature-based parametric history. Owing to its advanced graphical interface and superior performance, Pro/Engineer rendered many existing products obsolete and forced competitors to develop alternative solutions, often described as “Pro/E killers.” In 1988, Pro/ENGINEER further consolidated its position as a robust and innovative system.[24] In parallel, independent geometric modeling kernels emerged, including Parasolid (Shape Data, 1989), ACIS (Spatial Technology, 1989), and DesignBase (Ricoh, 1987), inaugurating a period of intense competition over solid modeling engines known as the “kernel wars.” That same year, Unigraphics acquired Shape Data and the Parasolid kernel, which went on to become an industry standard.[24]

On the hardware side, the decade was marked by the so-called “workstation wars” among Apollo, Sun, SGI, Hewlett-Packard, DEC, and IBM, culminating in Hewlett-Packard’s acquisition of Apollo in 1989 and the widespread adoption of RISC architectures. By the end of the decade, leadership in the CAD industry had been reshaped: Dassault Systèmes (CATIA), Parametric Technology (Pro/Engineer), McDonnell Douglas/Unigraphics, and SDRC (I-DEAS) dominated the market, while former leaders such as Computervision, CALMA, and Intergraph entered a period of decline.[29]

1990s

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3D rendering of a car in CAD software with boundary representation

Also important to the development of CAD was the development in the late 1980s and early 1990s of B-rep solid modeling kernels (engines for manipulating geometrically and topologically consistent 3D objects), Parasolid (ShapeData), and ACIS (Spatial Technology Inc.). These developments were inspired by the work of Ian Braid. This subsequently led to the release of mid-range packages such as SolidWorks and TriSpective (later known as IRONCAD) in 1995, Solid Edge (then Intergraph) in 1996, and Autodesk Inventor in 1999. Between 1992-1998 Robert McNeel & Associates develop, based in the OPENNURBS Kernel, the 3D CAD Application called Rhinoceros 3D. An independent geometric modeling kernel has been evolving in Russia since the 1990s.[30]

2000s

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Screenshot of BRL-CAD, an open-source CAD system used for geometric modeling and engineering analysis.
Autodesk Inventor: example of a technical drawing created with CAD software, representative of professional use during the 1980s.
CATIA: three-dimensional CAD model illustrating the transition from 2D drafting to full 3D design.

At the beginning of the 2000s, after the smooth resolution of concerns related to the Millennium Bug, the CAD software industry shifted its focus toward Internet-based solutions. Alibre introduced Alibre Design, the first web-based client–server 3D CAD system, while Autodesk released AutoCAD 2000i, adding online collaboration features. At the same time, increasing pressure to reduce product development cycles led Ford to adopt the integrated C3P platform (CAD, CAM, CAE, and PDM) to design the Mondeo entirely over the Internet, demonstrating the advantages of the “digital master” concept and collaborative engineering.[31]

The concept of product lifecycle management (PLM), derived from academic research on manufacturing databases, gradually replaced the notion of CAD vendors as purely “3D CAD” providers. Major industry players—including Dassault Systèmes, Parametric Technology Corporation, Unigraphics Solutions, and SDRC—reoriented their strategies and marketing toward comprehensive product data management. Significant corporate moves included SDRC’s acquisition of Metaphase, Unigraphics Solutions’ acquisition of EAI (a specialist in 3D visualization), and Dassault Systèmes’ acquisition of the ACIS geometric modeling kernel from Spatial Technology. In 2001, UGS acquired SDRC, while EDS repurchased the UGS stake it had previously divested.[31]

From a technological standpoint, no disruptive breakthroughs comparable to Pro/Engineer (1987) emerged during this period; instead, improvements focused on system usability and workflow efficiency. ThinkDesign introduced “Global Shape Modeling” in 2001, and PTC released Pro/ENGINEER Wildfire in 2003, emphasizing enhanced ergonomics and user interaction. Among newer entrants, ImpactXoft gained attention with IX/Speed and XXen, developed in collaboration with Toyota Caelum and later supported by Dassault Systèmes.[31]

By 2004, the industry was dominated by three major PLM vendors—IBM–Dassault Systèmes (CATIA, ENOVIA), UGS (Unigraphics, iMAN), and PTC (Pro/ENGINEER, Windchill)—alongside Autodesk, which remained active in the mid-range market together with SolidWorks (Dassault) and Solid Edge (UGS). Numerous smaller vendors survived through specialization and compatibility with the dominant platforms. According to industry observers, the radical innovation that had characterized the 1970s and 1980s appeared temporarily subdued, awaiting a new technological shift.[31]

As Internet connectivity expanded, CAD software increasingly incorporated tools for remote collaboration. Formats such as VRML and DWF, along with browser plugins, enabled distributed visualization of 3D models, while applications such as Microsoft NetMeeting allowed teams to discuss and manipulate models in real time.[32] At the same time, CAD software prices declined significantly, making advanced systems accessible to a broader audience, including hobbyists and students. Developers also began to standardize application programming interfaces (APIs), facilitating the integration of analysis, rendering, simulation, CAM, and surfacing tools directly into core CAD packages.[32]

The CAD sector also experienced notable developments centered on Pro/ENGINEER. In 2001, version 2001 introduced ISDX, a Class-A surfacing module derived from PTC’s acquisition of CDRS and later known as Creo Style, which became essential for consumer product designers. In 2002, Pro/ENGINEER Wildfire 1.0 redesigned the user interface and improved workflow efficiency. In 2007, Grasshopper for Rhino introduced a generative design approach, enabling algorithmic creation of organic forms with editable 3D outputs without requiring traditional programming skills. In 2008, Pro/ENGINEER Wildfire 4.0 added tools comparable to Rhino through Import Data Doctor, improving STEP and IGES data handling. In 2009, Autodesk sought to make Inventor more intuitive by enhancing support for complex assemblies, while Fusion 360 began to move CAD toward cloud-based platforms by integrating Alias Surfacing tools.[33]


Availability of free and open-source CAD software and high costs of advanced and 3D CAD software may restrain the growth of the CAD software market.[34] Free and open-source CAD software packages include FreeCAD,[35][36][37] BRL-CAD developed for the US Army,[38][39] QCAD Community Edition,[40] LibreCAD[41] and others.[42]

2010s

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During the 2010s, PTC expanded its portfolio through acquisitions and new product development. In 2010, the company acquired Co-Create, rebranding it as Creo Elements/Direct and integrating it into the Creo product family. In 2011, Creo 1.0 was released, featuring a redesigned user interface, the Sub-Divisional Modeling module (marketed as Freestyle), the retirement of the Pro/ENGINEER and Wildfire brand names, and the introduction of a dynamic context menu. [33]

In 2012, Jon Hirschtick launched Onshape, a collaborative cloud-based CAD platform often compared to Google Docs for its real-time, multi-user design capabilities. In 2013, PTC completed its first major acquisition related to the Internet of Things (IoT) with the purchase of ThingWorx, strengthening its presence in industrial IoT solutions. [33]

In 2014, Dassault Systèmes introduced the 3DEXPERIENCE platform, enabling SolidWorks users to access advanced tools traditionally associated with CATIA. In the same year, PTC acquired Axeda, further expanding its IoT connectivity and device management capabilities. In 2015, PTC continued its digital expansion strategy by acquiring Vuforia, a company specializing in augmented reality.[33]

2020s

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During the 2020s, CAD has undergone significant changes due to the integration of artificial intelligence (AI). Many tasks that were previously manual, time-consuming, or repetitive are now partially or fully automated, enabling designers and engineers to work faster and with greater accuracy.[43][44][45][46] AI-driven CAD systems improve productivity by automating repetitive operations such as inserting standard components, validating drawings, and checking compliance with technical constraints.[43][44][45][46] Some applications are also capable of reviewing designs and suggesting optimizations, reducing errors and rework while shortening development cycles.[43][44]

Generative AI acts as an intelligent assistant that can transform basic models into more complete and information-rich designs, automatically recognizing objects and organizing them within the project structure.[44][45] This approach enables greater design accuracy and facilitates compliance with technical standards without extensive manual verification.[44] In addition, AI-based tools increasingly support early-stage simulation and predictive analysis, allowing engineers to evaluate aspects such as structural performance or energy efficiency before the final model is completed.[45][46] By identifying potential issues earlier, these technologies help reduce material waste, prevent design errors, and contribute to more sustainable development processes.[45][46]

Chronology

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The following is a chronological list of major events related to the history of CAD software:

  • 1975 – ComputerVision (ComputerVision): An advanced CAD system for its time, introduced by the ComputerVision company.[47]
  • 1978 – Unigraphics R1 (United Computing): United Computing releases Unigraphics R1, a complete rewrite of the original code with new features and performance improvements. This version marks the beginning of the UGI series, while earlier versions were known as UGO.[52]
  • 1984 – CADAM (IBM): CADAM is commercialized by IBM as a CAD solution for industry.[47]
  • 1990 – AutoCAD (Autodesk): Continued releases expand the PC-based CAD market.[47]
  • 1992 – CADENAS / eCATALOG: The founding of CADENAS to create publicly accessible 3D model component libraries.[47]
  • 1994 – STEP: STEP becomes the international standard for transferring 3D data between different CAD systems.[47]
  • 1994 – AutoCAD Release 13: Introduction of 3D modeling into originally 2D CAD systems.[47]
  • 2002 – Unigraphics NX (EDS PLM Solutions): The first "Next Generation" release combining Unigraphics and I-DEAS into a single product.[54]
  • 2010 – Creo (PTC): PTC announces Creo, renaming Pro/ENGINEER as Creo Elements/Pro and integrating it into a unified product development platform.[56]
  • 2012 – Autodesk 360: One of the first CAD platforms to be fully usable in the cloud.[57]
  • 2016 – Onshape: A fully cloud-based CAD system accessible from any device and location.[47]

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