3D CAD Modeling Overview

What are 3D Models?

3D Modeling is the process of developing a representation of a three-dimensional object through the use of computer software. The product of which is called a 3D model.

Unlike 2D drafting tools, 3D modeling technology provides a more thorough and complete representation of a design, from the way parts fit and move together, to other characteristics such as size, strength, interferences, and mass.

The Benefits of 3D Modeling

3D modeling offers many benefits over traditional pencil and paper drafting, and even 2D computer drawing packagaes such as AutoCAD.

Some of these benefits are listed below:

  • Fully defined and detailed three-dimensional models and assemblies. Every component can be individually modeled and assembled, giving you the ability to understand the way things interface with one another and allowing you to see things you might have otherwise missed in the 2D representations.
  • Interference checks. Unlike 2D models, 3D assemblies can be rotated around to check for interferences, clearances and other concerns. Many 3D modeling programs have tools that will even check for interferences for you.
  • Design flexibility and ease of modification. With 3D models, most dimensions and relations are associative or parametric, meaning if you change one dimension, the remaining dimensions and mating parts will move accordingly. Previously on paper or with AutoCAD, one dimension change could force you to erase half of your work and redraw the new areas completely.
  • Hardware Libraries
  • Mass properties
  • Strength and force analysis (FEA)
  • Animation and simulation capabilities

Why we use 3D Modeling in Robotics

  • Strength Analysis – You can run simple tests to see if parts are going to break.
  • Bill of Materials (BOM) – With part numbers and model trees, you can more easily track the required parts to build your robot and later account for them when creating a BOM during inspection.
  • Interference Detection – You can see if your parts are going to interfere before you make them
  • Mass and Center of Gravity (CG) Calculations – You can see how much your robot will weigh, and figure out if it will tip over when the arm is extended.
  • Integration and Aesthetics – You can make your parts look good and more easily integrate sub-systems.

Software Programs

The following is a list of common 3D modeling programs used in the design and drafting industries. It does not include programs used for animation and other photo-realistic applications.

  • SolidWorks
  • Creo (Pro/Engineer)
  • Autodesk Inventor
  • Catia
  • Unigraphics
  • Solid Edge
  • etc.