Rigid body simulation for 3D character animation

The project

This project formed the basis of my final year dissertation for the Computer Science Tripos at the University of Cambridge in 2005/06. It was awarded the prize for the best dissertation of the year, and has been published as a technical report of the University of Cambridge Computer Laboratory.

How it works

You can read the report for full detail on the project, its development and the research involved.

You can also download the Java source code of the simulation core under a MIT License.

Demo videos

Download the full demonstration video (approx. 3 minutes, MPEG-1 format) of all aspects of the simulation:

• High quality (27 MB) (recommended)
• Low quality (6 MB)

Alternatively, you can watch each scene as an individual file:

• Pendulum systems: (implementation notes)
  • Double pendulum
  • Three-part pendulum
  • Eight-part pendulum
  • Rope simulation
• Newton's cradle: (implementation notes)
  • One ball moving
  • One ball moving (slow motion)
  • Two balls (from the same side) moving
  • Three balls (from the same side) moving
  • Two balls from one side, one from the other moving (slow motion)
  • One ball initially moving, not fully elastic (elasticity 0.9)
• Falling boxes: (implementation notes)
  • 10 boxes falling onto a table, elasticity 0.2
  • 10 boxes falling onto a table, elasticity 0.2 (slow motion)
  • 10 boxes falling onto a table, elasticity 1.0
  • 10 boxes falling onto a table, elasticity 1.0 (slow motion)
• Alfred falling down stairs: (implementation notes)
  • Intro to the scene
  • Falling down the stairs
  • Falling down the stairs (slow motion)
• Alfred and the spiral staircase: (implementation notes)
  • Intro and falling down the stairs
  • Falling down the stairs (slow motion)

For contrast, here are some incorrect animations produced in earlier versions of the program (the bugs have since been found and fixed):

• Falling boxes, sinking into the table
• Newton's cradle, constraints drifting apart

[www.kleppmann.de]