i’ve retrofitted my arnie (http://www.youtube.com/watch?v=lxAVy–IoBA) with this double-weighted pendulum. it’s the same principle behind a metronome (another hat tip to benvandewaal). i threw it together quickly, and i haven’t bothered to set the rate, just got it close to a seconds pendulum. the rate adjustment would be managed by adjusting the mass and/or position of the small weight at the very top.
even with 12 oz. bobs on either end, the pendulum’s q factor isn’t very good, so i had to make the gravity arm a bit heavier to compensate. i think the solution to improving the q factor is to significantly increase the mass of the bobs, but i’m just about out of weight elements.
Post time: 09-16-2017