Bored? Ideas for your 3D printer...
- Thread starter svetz
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svetz
Works in theory! Practice? That's something else
String Anemometer
Never heard of this being done...so a Will's Forum first! Or, it just might not work.
A taunt string in the wind should vibrate at a given frequency. You should be able to correlate the amplitude of the wave to the wind speed.
If one end of the string is affixed to a piezo-electric crystal, the amplitude should be measurable by the voltage.
Never heard of this being done...so a Will's Forum first! Or, it just might not work.
A taunt string in the wind should vibrate at a given frequency. You should be able to correlate the amplitude of the wave to the wind speed.
If one end of the string is affixed to a piezo-electric crystal, the amplitude should be measurable by the voltage.
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Bus Bar Covers - The space I've got all my stuff in is pretty cramped. Would love to be able to safeguard against accidental shorts when doing any work in there. Just dropped $$ for some Whia insulated tools and know that there are busses that come with covers, but not the ones I want/need. Might see what I have laying around that could work, but that's something I'd probably want to fab ... if I had a printer.
Everlanders bought a printer to fab housings for external DIY cameras and a Raspberry Pi/Android Auto-based overhead DIY console that were pretty cool.
Everlanders bought a printer to fab housings for external DIY cameras and a Raspberry Pi/Android Auto-based overhead DIY console that were pretty cool.
Unless you use a very special string it'll act more like a thermometer than an anemometer ? but +1 for originality.
svetz
Works in theory! Practice? That's something else
I can see where Temperature would change the string frequency, but the amplitude should still be related to the wind speed. A string temperature correction factor? Of course, kudos to you as this device can now get both wind speed (voltage magnitude) and temperature (voltage frequency)!
I suspect the bigger problem is low wind speeds would only create a vibration in the lightest possible guage of string (e.g., thinner than a hair). I know the crystals are pretty sensitive...but possibly not that sensitive.
svetz
Works in theory! Practice? That's something else
I keep hearing a 3D printer is the gizmo you never knew you needed until you have one. Of course, I want one but don't really have a need for it. <sigh> (even the string anemometer wouldn't really need a 3d printer). So why don't I just get one? Well ... see Will's post New tool.
If the tension changes because of change in temp then the amplitude will change (and of course the frequency too). Then, if the string is nylon or another plastic the damping will change thereby changing the amplitude.
Also, it is wind direction dependent... so now you can have wind speed, wind direction and temperature ? but there's more: if it's in the sun you can also get how much W/m² there is (because more W/m² = higher temp).
But don't ask me to give a transfer function for this thing because I can't...
svetz
Works in theory! Practice? That's something else
I'm not seeing the wind direction, could you run that by me again?
A silver vs a black metallic thread/wire might work for solar radiation as they'd have different strains on them - would need some sort of wind-correction factor to account for convective cooling or perhaps they're in a clear vaccum tube?
UPDATE: Don't need two wires for that, strain on a single wire should be consistent to solar energy if protected from other forces (e.g., humidity, wind).
Instead of wiring a wind-speed vibrator like a guitar string, the changing tension problem could be resolved by using a fixed weight.
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If the wind comes perpendicular to the string you'll have maximum amplitude but if it comes parallel you'll have minimum amplitude (theorically zero).
But then they wouldn't vibrate anymore...
That way you can measure changes in gravity too; I see what you did there...
But then they wouldn't vibrate anymore...
That way you can measure changes in gravity too; I see what you did there...
K, to many variables that are unknown. So add a thermometer, a hydrometer and a wind vane to account for those. But wait, wouldn't the airflow need to be laminar and perpendicular to the string AND the local gravitational field line? Need to add a gravimeter, which would also come in handy for addressing how the weight of the "fixed weight" might change over time. And even if you had a laminar wind, string-induced turbulence would impose some additional forces you'd need to account for, so string thickness needs to be some very small fraction of the size of particles that make up the wind. And then, of course, there's the at-a-distance forces resulting from "String Theory" itself. So, yeah, there's that too. ;-) Anybody got a 3D printer that can do all that?
Wait why are you talking about a 3D printer, that's not the topic... Ah, I see, it's in the title of the thread...
?
svetz
Works in theory! Practice? That's something else
Honestly, the thread is about 3D projects because your bored and have an idea as to how you'd use one to do something. Like Bus Bar Covers, perfect idea!
Feel free to ignore any extended discussions on String Anemometers (I can see where novel/unique is thought of as ridiculous/humorous as there are lots of problems not resolved).
I'm sure people laughed at sonic anemometers at first, but they have consistent data and with no moving parts are very reliable (and can give you wind direction).
Feel free to ignore any extended discussions on String Anemometers (I can see where novel/unique is thought of as ridiculous/humorous as there are lots of problems not resolved).
That's why it says the crystal is measuring strain rather than frequency for the solar radiation.
With a fixed mass it would have to be calibrated to the local gravitational field for accuracy, so I don't see that. It wouldn't work in zero-g either (but honestly, if there's a strong wind in a space ship you got bigger problems).
Theoretically it should be possible. Once you have the experimental data you could correlate it to known data and come up with a formula to interpret the data. The mark of a good measuring tool is that it is consistent over time. That is a 25 mph wind speed always give you the same amplitude repeatedly over years of use. I suspect that has more to do with the material science of the "string".
I'm sure people laughed at sonic anemometers at first, but they have consistent data and with no moving parts are very reliable (and can give you wind direction).
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Think you might be on to something. Of course, your control is to measure the wind speed with something else and calibrate the vibrations using that. The lookup table could account for all the other variables. The vacuum comment makes me wonder if one we've omitted is altitude/density. A 25 knot wind on Mount Everest is going to vibrate that string at a lower frequency than one at sea level, no? I'm also wondering if Heisenberg isn't a work here. Can we measure it without changing what it is we're measuring?That's why it says the crystal is measuring strain rather than frequency for the solar radiation.
With a fixed mass it would have to be calibrated to the local gravitational field for accuracy, so I don't see that. It wouldn't work in zero-g either (but honestly, if there's a strong wind in a space ship you got bigger problems).
The Humor section is the next thread down.
Just because no one has ever done it before doesn't mean it can't be done.
Theoretically it should be possible. Once you have the experimental data you could correlate it to known data and come up with a formula to interpret the data. The real question is would it be consistent? That is a 25 mph wind speed always give you the same amplitude repeatedly over years of use. I suspect that has more to do with the material science of the "string".
I'm sure people laughed at sonic anemometers at first, but they have consistent data and so are very reliable, and can give you wind direction.
Wait? Why are people still laughing???
Didn't saw the edit, but you can't measure strain with a crystal, you can only measure relatively quick changes in strain.
Or too much chili...
The problem is the difference between theorically and practically...
svetz
Works in theory! Practice? That's something else
Dhowman : You're right that an altitude correction factor should be added to the correlation for a String anemometer to account for air mass density/humidty. In practice, I'm not sure how much difference it would make.
Dhowman : Bus bar covers - So something flat that snaps down on top and covers the terminal post? Can survive a wrench strike?
cass3825: MT50 enclosure - Are you thinking like a NEMA 3r enclousure (somewhat weather proof)? Or just something to make a nice clean display like the link in Dowman's post above?
BiduleOhm: Didn't see the edit ... Sorry... I'm notoriously bad for posting and then taking another half hour in edits to polish it. Usually says exactly the same thing, hopefully more precisely and easier to comprehend. Wish I could just post correctly the first time. <sigh>
BiduleOhm: The .... difference between theory and practice Yup, it's my tag line after all.
Dhowman : Bus bar covers - So something flat that snaps down on top and covers the terminal post? Can survive a wrench strike?
cass3825: MT50 enclosure - Are you thinking like a NEMA 3r enclousure (somewhat weather proof)? Or just something to make a nice clean display like the link in Dowman's post above?
BiduleOhm: Didn't see the edit ... Sorry... I'm notoriously bad for posting and then taking another half hour in edits to polish it. Usually says exactly the same thing, hopefully more precisely and easier to comprehend. Wish I could just post correctly the first time. <sigh>
BiduleOhm: The .... difference between theory and practice Yup, it's my tag line after all.
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... in addition to the level of boredom we're experiencing, as evidenced (measured?) by this thread (aka "a string").
Well, I'm waiting answers for an even crazier idea, so...
@cass3825 by some miracle I have 2 good news and zero bad news about the 10 kA problem: it'll be a lot easier and cheaper than I anticipated to handle it; and I'll probably be able to use only 18 or even 16 mosfets instead of 20
Preee-cisely. Or I've left a tool sitting on top of my inverter and it falls off and shorts the bus bars when go over a bump. Yeah, that kind of almost-everyday scenario.
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