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 Mini Foucault pendulum

This short (12 cm) Foucault pendulum  was not specifically designed to be in the Guinness Book of Records but it is a good
candidate. I originally designed it as a test bench for the various materials of the suspension. As the pendulum oscillates much
faster than the other ones (over 171 oscillations per minute compared to 60) and with a larger amplitude (20°) materials wear
out much faster. The data collected here are used to improve the other pendulums.


(The bottle is only here to provide the scale)

Of course building this pendulum was by far a bigger challenge than all the other ones. The suspension wire is guided by
ceramics. I had to use two different diameter Charron rings to smooth out unwanted vibrations in the pendulum's swing. The
upper ring is a jewel, the second one is made out of brass. Using two rings also reduces the wire deflection angle and therefore
increases the suspension life.

The chassis is made of cast aluminium from a Berkel weighing scale. It is cast as one block. Don't believe it's an overkill: the
smallest torsion would influence the pendulum and cancel the rotation. Bear in mind that because of the small amplitude and
weight of the pendulum the rotation force is extremely weak.

This pendulum is not for sale.

English translation by Jean-Marc Julia