Interactive Rigid Body rotations with propulsion

While friction-less rigid body rotations are fascinating enough in of itself (see part one and part two of this series), the real fun starts when propulsion is added to the ‘equation’!

Below, I’ve extended my simulation model with 16 thrusters, arranged in four thruster quads. The model supports arbitrary thruster origins and thrust directions.

Because the model supports it, and for fun, I added the thrusters at the top of the body, and not around the center of mass. Also for fun, I slightly tilted the four ‘downward’ thrusters away from the body so that the virtual exhaust does not hit the body.

The thruster arrangement is more or less identical to the one used on the Apollo Program’s Lunar Module.

In the interactive simulation below you can control individual thrusters by pushing the thruster buttons.

The maneuver buttons control more than one thruster to execute more or less clean rotations like yaw, pitch and roll, and translation along one major axis.

The angular momentum vector is visualized as a yellow arrow. The angular velocity vector is visualized as a green arrow.

Have fun!

Quad 0:
Quad 1:
Quad 2:
Quad 3:

L =
kg m2 s-1
ω =
Ibody =
+360.97 +0.00 +0.00
+0.00 +1321.37 +0.00
+0.00 +0.00 +1600.67
kg m2

Erot = 0.000 J
Etrans = 0.000 J
|L| = 0.000
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