Just having a quick catch-up on the thread progress ..
Hey dax .. I think you may have asked about the double geared pends and this jogged my memory ..
This is a sim study I did many years ago - I dusted it off this morning and tidied it up a bit ..
We all know if they are orientated vertical or horizontal there is no tendency to open or close because each pend will lose the same GPE, so they don't move ..
What may be sometimes overlooked is that a circle at 30 degrees from horizontal is the half vertical height distance ( not 45 degs ) - rim distances to North and East are different - as the animation and sim shows the pends will move by themselves to lose NET GPE in most positions if frictionless like in this sim study etc ..
That's because like a Roberval Balance ( Ramelli Geared Balance ) they can't move unless one side can lose more GPE than the other i.e. lose net PE - if there is a potential to lose more than the other they will move ..
Anyways, thought you might find it interesting and appropriate for this thread on double geared pends .. n.b. the sims all begin moving at different times - this is a sim thing that I don't have an answer for as the gears have no frictions that I'm aware of but it just might be slight inaccuracies in copying across .. the green dampers between the bobs is deactivated and their middle positions indicate the COM between the bobs while in motion ( a visual cue ) etc ..
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