What are some good rigid body dynamics references?

Question

I'm not a math guy in the least but I'm interested in learning about rigid body physics (for the purpose of implementing a basic 3d physics engine). In school I only took Maths through Algebra II, but I've done 3d dev for years so I have a fairly decent understanding of vectors, quaternions, matrices, etc. My real problem is reading complex formulas and such, so I'm looking for some decent rigid body dynamics references that will make some sense.

Anyone have any good references?

Answer 1

Physics for Game Programmers I think is better than Physics for Game Developers.

If you want something thick in your bookshelf (like I do), Eberly's 3D Game Engine Design and Erleben's Physics-Based Animation can accompany the above.

Answer 2

Chris Hecker has a nice set of articles on his website which were originally published in Game Developer Magazine. They start with 2D physics and progress to 3D.

Physically Based Modeling by David Baraff is also good, but is a bit heavier on the math.

Answer 3

I guess what you are looking for is Classical Mechanics, which describes motion in one, two, and three dimensions in a generalized manner.

I found a good introductory course on Classical Mechanics from the University of Texas.

I do not guarantee that you will be able to understand all the concepts there, but it will at least give you a basis for your plan. I advise you to consult a Physics professor to help you understand the math.

Good luck!

Answer 4

If you are already familiar (and comfortable) with

• linear algebra
• basic calculus
• Newton's laws of motion

then 6DoF Rigid Body Dynamics is what you are looking for. It's a brief article written [disclaimer: by me] when I once had to develop a helicopter flight simulator.

Using a rotation matrix allows for extremely simple modelling equations, but there exists a simple mapping to and from a quaternion if you prefer that representation for other reasons.

Answer 5

Trying not to get you to rip off your hair with frustration (well, Baraff's/Witkin great math articles with the multi-dimensional matrices would do that sometimes), you can look at the easier online articles such as the ones published in Gamasutra. Here are two of them:

1. http://www.gamasutra.com/resource_guide/20030121/kennedy_pfv.htm
2. http://www.gamasutra.com/features/19990702/data_structures_01.htm
3. http://www.gamasutra.com/resource_guide/20030121/jacobson_pfv.htm

You'd notice that they point at the mentioned resources as part of their references. I would add that unless you need to solve equations system for multiple particles, articulated characters, or non-rigid complex object, this might be enough to start with.

If however, you do look for more advanced physics and mathematics which involves matrices and equations systems look up Witkin and Baraff's home pages (I think they are both in Pixar if I'm not mistaken), or start with Hecker (that tried more than several practical methods and documented his results).