Nomer
437
Some real food for thought here!
May 03, 2010,15:35 PM
It will probably take a few days to digest and comment more fully, but I wanted to note that in the PurstS discussion you linked there is a further link to a 2002 article on the watch (search for "LINK" in the discussion). That paper notes the behaviour of each of the escapements when connected to a timing machine that can track each vibration. As "resonance" is achieved, the two patterns are said to merge into one much like the oscillation video you posted (excellent video!) of the metronomes. The latter seem highly relevant to the mechanism in the resonance, although I would have thought at first guess that the mechanism in the watch is less dramatic since momentum is not likely conserved (i.e. the cans on which the oscillators are allowed to sit can move freely back and forth while the escapements can "interact" in a more constrained way - probably much like Huygens clocks. In any case, probably wise not to speculate ahead of more thought and reading.
Thanks very much for doing this research and making it easily accessible - no doubt this will provide for a few days of thought and hopefully some insight. All the best.
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"An odd kind of sympathy"
By: donizetti : May 3rd, 2010-12:00
I have been trying to come to grips with the principle underlying the Resonance. This topic has been discussed before ahci.watchprosite.com but I am not sure there is a conclusion yet. The following is what I have collected from the literature for your co...
Some real food for thought here!
By: Nomer : May 3rd, 2010-15:35
It will probably take a few days to digest and comment more fully, but I wanted to note that in the PurstS discussion you linked there is a further link to a 2002 article on the watch (search for "LINK" in the discussion). That paper notes the behaviour o...
Agnostic
By: AndrewD : May 3rd, 2010-15:53
Very interesting discussion paper, Andreas, Thanks. I don’t have any answers but I do wonder if Mr Journe experimented with different distances between the balance wheels when designing the first Resonance watch. If the synchronisation phenomenon has some...
At 5280 feet (1586 m)...
By: chaser579 : May 3rd, 2010-17:01
"F.P.Journe already point out..that altitude can influence the chronometry of their watches." I wonder if that's true out here in Denver, Colorado at 5280 ft/1586m? That would be interesting to study, besides the inherent 'dryness' of this sem-arid portio...
Let me try to answer...
By: Ogygia : May 3rd, 2010-21:14
what would happen if a Resonance was run in a vacuum? I think we have to consider how these oscillators damp each other. For Journe's, he use the "rack and pinion" to adjust the angle of the balance bridge. Thus can adjust the distance between 2 balance w...
typo before....and for the adjustment
By: Ogygia : May 4th, 2010-19:10
The effect on the air fiction damping depends on altitude not the latitude... Higher humidity, higher air density... bigger fiction... In my point of view...the adjustment on the distance of 2 balance wheel is the key the control the type of the damping e...
Test done a couple of years ago.
By: Terry O : May 3rd, 2010-22:10
Andreas: About three years ago, a FPJ Resonance owner had his watch placed in a vacuum chamber (the type used by dealers to test water resistance of a case) with the back removed. When air was removed from the vacuum chamber, the balance wheels quickly lo...
Thanks Ogygia and Terry …
By: AndrewD : May 4th, 2010-15:18
The information is much appreciated. So this confirms that it is air turbulence or, perhaps, friction causing the “resonance” effect. I wonder if at higher air pressures the synchronisation would be greater (even if the accuracy was affected)? What effect...
so if air is the coupling medium ...
By: donizetti : May 5th, 2010-12:55
... I think the logic outlined in the Royal Society paper would still apply. I.E the motion of the balances in perfect anti-phase should be the least dampened, because the balances movement at the point at which they are close (in the middle of the moveme...
In my wordings..
By: Ogygia : May 5th, 2010-20:24
I can't agree more on what you said.... IMO, we can focus on the area where 2 balance wheels close to each other. So we only consider up and down motions as it is easier to understand ... If they move up and down exactly in same timing, there is almost no...
air
By: donizetti : May 5th, 2010-03:43
That's very interesting. Did you find it? In principle, I guess vibrations should be transmitted through air and the force would fall off with the distance, so if the balances are really close, which they are, this could be the source of the synchronising...
Perhaps in a vacuum
By: amerix : May 5th, 2010-04:34
the balance wheels would have to be moved closer to each other - perhaps too close to prevent them from touching if subjected to shock. Also Bernoulli's Principle (which enables airplanes to fly) would have no effect in a vacuum, thanks to reduced (here n...
Sympathy for the Resonance
By: amerix : May 5th, 2010-04:12
There is an remarkable series of lectures by Walter H. G. Lewin before a freshman physics class at MIT. I single out Lecture 30: Simple Harmonic Oscillations - Energy Considerations - Torsional Pendulum videolectures(dot)net(slash)mit801f99_lewin_lec30 an...
Great post and thread!
By: schen : May 5th, 2010-07:48
I am never tired of learning the secret behind the Resonance, though never really got it... which just makes the Resonance even more fascinating. BTW, here is another good read that has been posted here before: www.watchprosite.com /
