What is CAD (computer-aided design)?

What is CAD mainly used for?

CAD software products are mainly used to digitally design 2D drawings or 3D models to help visualize real objects before the objects are physically produced. The drawings and models are also used to review, adjust and modify a product's design before resources, time, effort and money are spent on creating a physical version.

In addition to creating realistic conceptual designs for products and detailed layout representations of components or entire systems, CAD may also be used to do the following:

• Represent elevation views in a built environment.
• Show how the various components of a system work together.
• Show where additional inspections or effort may be required.
• Support strength and dynamic analysis of an assembly.
• Define or tweak a component's manufacturing methods.
• Generate a bill of materials (BOM).
• Simplify parts creation with computer numerical control (CNC) manufacturing.

Benefits of CAD

CAD replaces the need for engineers, architects and other design professionals to create designs using pen and paper. In doing so, it optimizes and streamlines the designer's workflow and increases their productivity. The use of computers and software also improves the quality and level of detail in the design and often simulates a product's real-world performance better than is possible with human-rendered, hand-drawn designs.

Another benefit of CAD is that it improves documentation and project-related communications. The software provides annotated information about the materials and procedures required to create a particular product, as well as its specific measurements and tolerances. It may also document various tasks, the importance of each task and the interaction points between stakeholders and materials -- all of which help to improve collaboration and the final design.

Finally, CAD often contributes toward a manufacturing design database, which plays a crucial role in creating more precise designs and innovative products, reducing production costs, accelerating time to market and improving product quality.

The use of CAD tools can have significant benefits compared to traditional technical sketching and manual drafting:

• Lower production costs for designs.
• Quicker project completion due to efficient workflow and design process.
• Changes that can be made independent of other design details without the need to completely redo a sketch.
• Higher quality designs with documentation, such as angles, measurements and presets, built into the file.
• Clearer designs, better legibility and ease of interpretation by collaborators, as handmade drawings are not as clear or detailed.
• Use of digital files that can simplify collaboration with colleagues and stakeholders.
• Software features that can support generative design, solid modeling and other technical functions.

CAD software output

CAD software outputs come in the form of electronic files, which are then used for various manufacturing processes. The format of each CAD output file is either native or neutral. Both formats have their pros and cons.

Examples of native files include DWG by Autodesk, SLDPRT by SolidWorks, CATPart by CATIA V5 and SchDoc by Altium.

The main issue with native CAD files is that they can only be viewed using the program that created it. So, if a user needs to view a file but doesn't have the original program, they first need to install the program. On the positive side, native files perform well on the original program, ensuring that the user can use all the software's functions and features to interpret and use the information as needed.

Unlike native CAD files, neutral files are universal since they model data based on the STEP format (Standard for the Exchange of Product model data). This enables users to view and use the files across different CAD software products. A potential drawback of universality is that the file behaviors may vary depending on the software used; for example, they may not show the same information. Or, the import/export methods may vary, which may create unnecessary delays due to the learning or adjustments required on the part of the user.

Examples of neutral CAD file formats include .stp, or STEP; .stl, or stereolithography; .igs, or Initial Graphics Exchange Specification; .pdf, or 3D Portable Document Format; and .dxf, or Drawing Interchange Format.

Who uses CAD?

CAD use cases are specific to industry and job functions. Professionals that use CAD tools include, but are not limited to, the following:

• Architects.
• Engineers -- aerospace, transportation, civil, etc.
• City planners.
• Graphic designers.
• Animation illustrators.
• Drafters.
• Fashion designers.
• Interior designers.
• Exterior designers.
• Game designers.
• Product designers.
• Industrial designers.
• Manufacturers.

CAD software and tools

A number of CAD tools exist to assist designers and engineers with product design and simulation processes. These tools mainly fit into one of three categories:

1. 2D CAD. The software creates 2D geometric shapes, like lines, rectangles, squares, etc., to represent designs. Most 2D CAD products include a library of shapes and hatch patterns and can automatically create a BOM.
2. 2.5D CAD. These products are mainly used to aid in CNC machining. They simplify parts manufacturing by generating contour maps and by representing objects' depths -- two things that 2D CAD software cannot do.
3. 3D CAD. These applications are ideal for projects where realistic models must be produced to accurately represent a finished product and address potential problems early in the production lifecycle.

Many CAD tools are tailored to fit specific use cases and industries, such as industrial design or architecture. Others support a variety of industries and project types. Some of the most popular CAD tools are the following:

• 3D CAD by SolidWorks.
• Altium Designer by Altium.
• AutoCAD by Autodesk.
• CATIA by Dassault Systèmes.
• IronCAD Design Collaboration Suite by IronCAD.
• LibreCAD (open source).
• MicroStation by Bentley Systems.
• Onshape.
• OpenSCAD (open source).
• Solid Edge by Siemens.

When choosing a CAD software, the user organization should define its specific needs and goals and then confirm that the products under consideration meet its requirements. It's also important to check the software's file formats and confirm that they are compatible with other software being used in the design workflow. Finally, it's advisable to work with a vendor that provides tailored support, training and product documentation.

CAD and CAM

CAD is often used in tandem with computer-aided manufacturing (CAM) in digitized manufacturing processes. CAD and CAM software is used to design products such as electronic circuit boards in computers and other devices. Even so, CAD and CAM are two different concepts.

CAD is about creating 2D or 3D digital models of real-world products. Designers, drafters and others use CAD software to create renderings and vector-based drawings that result in the final model of a finished product.

CAM software uses these models to create a program for manufacturing the product. The manufacturing program consists of G-code that translates the digital model created by CAD into detailed manufacturing instructions that a machine can understand to carry out manufacturing processes, like cutting, milling, lathing and grinding.

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