Welcome to Physically Based Modeling
with Computer Graphics!

by Brent Perteet

This tutorial is intended to guide the reader through the process of modeling a real, physical system with both computer graphics and a dynamics engine capable of modeling the dynamics associated with a physical system. The tutorial combines two off-the-shelf packages that will aid in accomplishing these goals - OpenSceneGraph and Open Dynamics Engine. Each of these products are mature, cross-platform, open-source C++ packages which have been used in many projects.

This tutorial will demonstrate how to integrate these open source packages to model a real, physical system. This system will be wheeled, mobile robot in an environment with movable obstacles. The model will take into account physical forces such as gravity and friction as well as collisions between objects. The tutorial includes the full source code used to create the model and user interface. The tutorial is not intended to be a comprehensive treatment of physically based model, but discusses the most important aspects of the code used to create the vehicle, obstacles, and the simulation itself. The source code is provided to motivate further investigation into this topic.

The tutorial is organized according to the following outline:

System Requirements

This tutorial has been designed for use on the Microsoft Windows platform. Additionally, these tools and packages are required:

• Microsoft Visual Studio .NET 2003
• OpenSceneGraph
• Open Dynamics Engine
• Trolltech Qt v4.0

Although Visual Studio .NET 2003 is not specifically required to use the C++ packages OpenSceneGraph, Open Dynamics Engine, and Qt, the tutorial will illustrate how this development environment should be configured in order to use these tools together. The reader may wish to implement the tutorial examples on another platform such as Linux; however, instructions for configuring the environment are not be provided here.