Computer Aided Design (CAD)


What is Computer Aided Design (CAD)?

  • Computer aided design (CAD) is used to draw 2D and 3D designs on computer
  • CAD sofware pacakges can be downloaded and used to create designs on a computer
  • CAD software:

    Advantages Disadvantages
    • Designs can be created, saved and edited easily (saves time)
    • Designs can be easily copied/repeated
    • Designs can be easily sent to other offices/clients etc
    • Designs can be worked on by remote teams simultaneously
    • Designs can look photo-realistic to gain opinions from clients
    • CAD is very accurate
    • CAD software such as FEA/CFD can test design ideas under stress/aerodynamics
    • CAD sodtware is complex to learn
    • Software can be very expensive
    • Need a robust IT system/powerful computer
    • Compatibility issues with software between users
    • Security issues - risk of data being corrupted/hacked

    Uses: Design of buildings, bridges, structures



    3D modelling for creating 'virtual' products:

    Advantages Disadvantages
    • Don't have to wait for parts to dry
    • Reduces development time/costs
    • Can be easily adjusted
    • No material wastage
    • Can be produced on CAD
    • No physical feel of product
    • Weight can't be measured
    • Need a robust IT system/powerful computer

    Uses: Virtual modelling of prototype products



    Wire frame models (CAD):

    Advantages Disadvantages
    • Faster
    • Less memory space
    • Easier to send
    • Design shows little detail/colour of design

    Uses: Structural designs



    Surface modelling (CAD):

    Advantages Disadvantages
    • Realistic 3D view
    • Easier to understand
    • Needs a powerful computer
    • Time cosuming rendering design
    • Lots of computer memory required
    • Does not show internal features

    Uses: Models, CGI



    Finite Element Analysis (FEA): FEA is a computer run numerical method used to predict how an object/structure will behave under given conditions (e.g. loads and stresses). It can be used to find weak spots in designs and points of failure.

    Computational fluid dynamics (CFD): CFD is a computer run numerical method used to study how steady and unsteady fluids (e.g. Gas and Liquids) flow over objects. It is often used for aerodynamic study.



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