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By UnTuckable
#48144
Lobido wrote:Glad to have you on the forum. How long have you been flying, and what is your wing?
The wing in my avatar is a 20' Eipper Standard :thumbsup:
I haven't flown in awhile, so no current wing, I have a old WW HP-AT, HPII, WWDuck tho

For finding thermals, I think it boils down to density, ie a thermal would be a small
low pressure area with a small pressure gradient around it.

With pressure sensors on each wing tip (quad or stereo vario ;)
might yield a nice pressure map, compensating for bank, etc.
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By gerg
#48150
I may just spend a few bucks and buy one of these, instead of worrying about coding up the data logging logic myself. Especially since the data logger would probably not be part of the end-product... but could easily be an optional plug-in for development and fine-tuning.

E.g.

Temp Sensors | Pressure Sensors > MCU > Audio Out | Data Out

http://www.ghielectronics.com/
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By nighthawk49
#48330
Back in 92 this pilot use toilet paper. Being at 12grand over Chelan with toilet paper floating every where. As a HG 2 it work for me. :lol:
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By mgforbes
#51069
I found this part in a magazine ad today...looks interesting!

Melexis MLX90614 Infrared thermometer in TO-39 package
http://tinyurl.com/24lhxf

This is a complete infrared thermometer, consisting of a
thermopile and signal conditioning circuitry, along with an
analog-to-digital converter and linearization table. It outputs
either serial clock-and-data, or a pulse-width-modulated
signal.

What that means in non-geek-speak, is a simple, fairly
cheap gizmo that can tell you the temperature of whatever
you point it at. So imagine this mounted on your helmet,
so that as you look at terrain below, you get a readout of
whether it's hotter or colder. You might use this to find
the hottest field, or the warmest part of the hillside, or scan
for warm/cool spots on an XC flight. It won't read air temperature,
but it'll tell you the surface temperature of whatever you point
it at. It has about a 40 degree cone of sensitivity, which could
be adjusted with suitable optics.

As with the temperature sensor I mentioned earlier in this thread,
it's a complete sensor-to-digital solution, requiring no calibration
or adjustment. Single piece quantities are $25-ish, volume under $10.
You still need a CPU, display and so forth, but I was surprised at
how low cost the basic sensing technology has become.

MGF
User avatar
By saltoricco
#51072
mgforbes wrote:I found this part in a magazine ad today...looks interesting![...]
Wow, interesting! Thanks for the report, Mark. I talked with Scott Silver on Sunday, and he thought along the same lines. He could really help, but said he's currently more interested in getting his bank indicator (gyro, row of LEDs) going. He thinks the GPS won't be of much help when standing more or less still over P. Butte in a white-out, but in fact turning back unnoticed. Spring is coming, he should rather work on something to find the thermals. :) I'll bug him again to connect with you.

Holger
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By gerg
#51078
Very interesting... I wonder what the range is on that thing. And what kind of optics you'd need...

On the Gyro/bank indicator, this was an interesting article:
http://www.flyingmag.com/article.asp?se ... cle_id=265

I wonder how much better those sensors have gotten in the last 5 years.
By Old newby
#51088
--------------------------------------------------------------------------------

Flying with a friend who has used one for years convinced me they work. We would be on glide looking and if his snooper went off we would make a sweep and often find lift we would have flown by. I might be working something light as he flys towards me and his snooper goes wild so he would tell me it is bigger, then I would open up my turn to find a bigger core or adjacent thermal. I bought a new old stock one and flew with it for a while before misplacing it. It was useful on launch and on light days and on glide but it was also annoying (it talks alot!) not easy to turn on and off and one more piece of gear. In Eastern Oregon I have flown thermals originating from mint fields where you smell the lift before the vario sounded. Maybe you could train small dogs to help sniff out lift?
By blindrodie
#51113
My buddy who works at Garmin came out to fly with a GPS unit that had a GPS based bank indicator on it. Seemed to work very well.
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By CHassan
#78625
Thermal Snooper for sale on e-bay. $9.50 at the time of this posting.
#400202
Think about this.....

A sensor on each wingtip and a differential amplifier connected to a display which shows the hot or cold wingtip etc...etc.

variable gain...variable off set ...the mind boggles

the sensors would need to be in airflow and protected from sunlight ....
Just another thing that should work and with all the arduino and the like ..relatively easy to do.

Fast acting sensors are key here

likely to be something for comp pilots or geeks ...but it may be possible to use this to find the core quicker ...but does that remove the fun?

and running the wire would be a pain for sure
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By TjW
#400221
Differential temperature sensing has been tried by various people in various ways pretty much since op amps became reasonable to power with batteries.
Many of these attempts have been in sailplanes, with a larger span than hang gliders.
So far as I know, there hasn't been any notable success.
The temperature differential in a thermal is small, and there's mixing near the edges.
Pulling a millidegree signal out of a lot of noise fast enough to be useful seems to be a hard problem.
#400359
The last few times I've been thermalling, my vario was broke. I still did OK, even pretty good, and I'm no Sky God. It was actually kind of liberating, no distracting beeping... But if a ThermalSnooper could turn a sled-ride into a sky-out, I'll buy one! Push out, /jd
#400518
I had one. Never thought it made much difference. Tended to always be beeping - but no confirmation with vario. Maybe I'll dig it out of the box of obsolete stuff and try it again.
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By raquo
#400519
I wonder if a thermal snooper would make sense at launch instead of in flight. Maybe to distinguish thermals (hot) from lee side rotor (cold?)... I'm sure you can build one fairly easily with Arduino and a proper off-the-shelf temperature sensor given enough time.