In order to demonstrate how a cat can
turn over over in mid air and land on its feet without a torque,
a mechanical model has been constructed and is demonstrated in this
movie. This model was constructed from copper tubing, springs, and
other metal parts. When this "mechanical cat" is released
from an upside down position with its back to the ground, it flips
over to land on its feet. The net torque and the net angular momentum
remain zero throughout the entire time.
