Everything You Need To Know About Computer Aided Design (CAD)
The phrase Computer Aided Design (CAD) means the use of computer software to facilitate the generation, modification, and optimisation of a part or a compilation of parts. Using software to facilitate part design allows for higher precision, simpler and more accurate design iterations, and comprehensive documentation for part and / or project management (e.g. integration with a traditional bill of materials).
There are a number of different software vendors that provide CAD software.
At Nova Design for our CAD Design services we use a mix of virtually all of the current range of 3D solid modelling CAD packages including SolidWorks, Inventor, Solid Edge, Catia and Siemens NX.
One of the enormous benefits of CAD software is the ability to automate 3D imagery and integrate different pieces of the same product in tandem with one another.
- CAD allows for simple and accurate automation and / or process modelling (known as Mechanical Design Automation or MDA). Traditionally MDA was not possible without first building a physical prototype of every part in the system and then assembling it to check functionality. The ability to digitally model and automate a prototype before ever generating a physical model adds enormous efficiency to manufacturing processes and cost reduction benefits.
- CAD allows for highly accurate dimensional analysis and mathematical scalability using vector graphic technology (digital images based on mathematical formulas).
- CAD provides highly precise part tolerance (much lower margin of error between parts).
- CAD allows for the ability to conduct Computer Aided Manufacturing (CAM). For example, integrating CAD technology with Computer Numerical Control (CNC) machines or Additive Manufacturing processes (3D printers).
- CAD takes into account material properties and interactivity characteristics between different materials.
The History of Design and Introduction of CAD
The use of computers to facilitate or assist design has been around since the mid-20th century. The term “Computer Aided Design” (CAD) emerged in the 1950s and is commonly credited to Douglas Ross, a computer scientist who was working at MIT when the acronym was coined.
Computer and Hardware Development for CAD
1943 : The first general purpose computer was developed in 1943 through the combined effort of US Army personnel and the University of Pennsylvania’s Moore School of Electrical Engineering. It was named the ENIAC (Electronic Numerical Integrator And Computer) and was used principally to calculate ballistics for US Army artillery shots.
1953 : The first graphics formed through mathematical equations took place roughly ten years later and involved the use of acomputer numerical controlmachine and a cutting tool (rather than the electronic displays you think of today). These earlyCNC machinestranslated time and position inputs (x, y, and z coordinates) to make cuts in the form of common shapes (the earliest “graphics”).
1964 : In the early 1960s the first commercially available Computer Aided Design (CAD) systems were coming out on the market. The first of these were used by large aerospace, engineering, and information technology companies like Lockheed, General Motors, and IBM.
One of the first computerised graphical display systems, the “DAC-1” (which stood for Design Augmented by Computer) came out in 1963 as part of a joint project between two of the aforementioned companies (GM and IBM). GM unveiled the technology in 1964 used it for nearly a decade until it was eventually replaced by a superior iteration.
CAD Software Development
1963 : CAD took an enormous step forward with the introduction of SKETCHPAD in 1963 by Ivan Sutherland, then working at MIT. Also known as “Robot Draftsman”, Sketchpad was a novel step forward in the field of human-computer interaction and was a major breakthrough in computer graphics in general. Of the major advances include the introduction of a graphical-user-interface GUIA graphical user interface allows users to interact with a computer device through visual aids (icons). This is contrasted with the more traditional method of computer interaction using text and object-oriented programming.
1971 : Another major step forward involved the introduction of Automated Drafting And Machining (ADAM). ADAM was a CAD system designed by Dr. Patrick J. Hanratty whose company, Manufacturing and Consulting Services (MCS), provided the software for major companies like McDonnell Douglas and Computervision.
Mid 1970s – Mid 1980s : 3D CAD was first introduced in the 1970s but not in a widely distributed fashion. CAD was still an expensive tool and general industry couldn’t afford to invest in this modern technology.
3D CAD was mainly the preserve of the automotive / aerospace industries where the end product has high value. General industry was still using the good old A0 drawing board with pencil, eraser and paper.
1980s – mid 1990s : As technology moved on at an ever increasing pace and IT hardware / software became more commercially available, Nova were one of the first mechanical design offices to invest in this modern design tool called CAD – Computer Aided Design software. To put things into perspective, Nova’s first CAD workstations ran on Windows 3.1.1 (the last .1 being the network edition of Windows 3.1), had <300MB hard drives and a massive 4MB of RAM !
Late 1990s to today : General industry slowly but steadily moved in the world of 3D CAD, first using AutoCAD 3D for wireframe and solid modelling, then utilising software such as early versions of Inventor, SolidWorks and Solid Edge.
Simon Parry, Director of Business Development at Nova reveals :
“We started into the 3D world with the first version of Autodesk Mechanical Desktop around 1995. The progress in 3D CAD was gradual where the step towards AutoCAD in the 1980s was much easier. In 2D CAD you were drawing the same way you always had. It (2D CAD) took almost the same amount of time as doing 2D drawings by hand with the big difference being that changes were much faster and easier to make. 3D CAD was an entirely different way of thinking and working and consequently took much longer for everyone to adapt to it.”
Over the years, Nova have invested in additional CAD systems and associated tools including Mathcad for calculations, Ansys DesignSpace for Finite Element Analysis (FEA) and a variety of CAD libraries to speed up the design process.