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Author Topic: Wavinator  (Read 214 times)

Jeremy McCreary

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Wavinator
« on: August 27, 2019, 08:49:46 PM »

Many of us use strings to spin tops. But what about spinning the strings themselves?

https://www.youtube.com/watch?v=0RbuIlEZIpM

You can see the device itself at 11:10. See video description for details.

« Last Edit: August 27, 2019, 09:00:24 PM by Jeremy McCreary »
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Playing with the physical world through LEGO

the Earl of Whirl

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Re: Wavinator
« Reply #1 on: August 28, 2019, 08:28:21 AM »

Wow!  Quite interesting.  "Trippy" is right.
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Happiness runs in a circular motion!!!

ta0

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Re: Wavinator
« Reply #2 on: August 28, 2019, 12:11:45 PM »

Fantastic! I love it!  ;D

Changing the span by changing the arm angle is mechanical genius.
It would be nice to be able to also adjust the phase in real time. But it's a bit complicated mechanically.
It could also be interesting to switch the rotation direction of one with respect to the other . . .
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Jeremy McCreary

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Re: Wavinator
« Reply #3 on: August 28, 2019, 12:29:46 PM »

Fantastic! I love it!  ;D

Changing the span by changing the arm angle is mechanical genius.
It would be nice to be able to also adjust the phase in real time. But it's a bit complicated mechanically.
It could also be interesting to switch the rotation direction of one with respect to the other . . .

Thanks! Given that much of modern physics is based on standing waves of one kind or another, thought you might get a kick out of this.

Would love to have phase adjustment on the fly. Not entirely out of the question, either. But as you said, the drivelines would get a lot more complicated. And that would mean less delivered power and torque at the string mounts.

The good news: A phase change takes 10 seconds.

For this to work at all, the string mounts must spin in the same direction at exactly the same speed. Otherwise, the string winds up or unravels. Hence one motor turning 2 identical drivelines.
« Last Edit: August 28, 2019, 12:36:18 PM by Jeremy McCreary »
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ta0

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Re: Wavinator
« Reply #4 on: August 28, 2019, 12:58:00 PM »

For this to work at all, the string mounts must spin in the same direction at exactly the same speed. Otherwise, the string winds up or unravels. Hence one motor turning 2 identical drivelines.
Yes, of course  :-[
Unless you put a swivel in the middle of the string. ;D
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Jeremy McCreary

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Re: Wavinator
« Reply #5 on: August 28, 2019, 01:09:01 PM »

For this to work at all, the string mounts must spin in the same direction at exactly the same speed. Otherwise, the string winds up or unravels. Hence one motor turning 2 identical drivelines.
Yes, of course  :-[
Unless you put a swivel in the middle of the string. ;D

Hmmm, visions of fishing line swivels dancing in my head now.
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Jeremy McCreary

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Re: Wavinator
« Reply #6 on: September 09, 2019, 04:50:01 PM »

A fancy high-tech version of the  wavinator recently appeared (and apparently failed) on Kickstarter at a projected $340 retail.

https://www.kickstarter.com/projects/northerncircuitsinc/string-of-pisces/description?lang=de

Love their string lighting approach with the phased RGB LEDs. Largely makes up for the limited number of attainable modes -- a direct consequence of having only 1 string and 1 string contol (speed). Span and free string length are fixed.
« Last Edit: September 09, 2019, 05:17:14 PM by Jeremy McCreary »
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Pepe

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Re: Wavinator
« Reply #7 on: September 13, 2019, 04:56:46 AM »

Im loving this sooo much!!!

Im dreaming of one stage size for a performance WOWOW
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Jeremy McCreary

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Re: Wavinator
« Reply #8 on: September 13, 2019, 12:59:18 PM »

Im dreaming of one stage size for a performance

The dynamic depends on several nondimensional ratios like (span) / (free rope length). So it should scale up with the right rope weight.

The main engineering challenge: Rope ends must spin at exactly the same speed.
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Jeremy McCreary

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Re: Wavinator
« Reply #9 on: September 13, 2019, 10:48:12 PM »

Speaking of standing waves...

Ecola Creek hosting 2 standing wave systems side by side as it cuts across the beach bar at low tide in Cannon Beach, OR after last night's rain. The nearer wave system has the longer average wavelength.


« Last Edit: September 14, 2019, 12:53:28 AM by Jeremy McCreary »
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