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Bill D
October 24th 12, 12:26 AM
Even with PowerFLARM on "stealth" pilots may soon have another way to find the next thermal. The DARPA "One Shot" initiative will develop a rifle scope which uses LIDAR to detect and correct for crosswind "windage". The Israeli Soreq Nuclear Research Center has already been granted a patent on the LIDAR technology.

http://www.accurateshooter.com/optics/new-wind-reading-lidar-laserscope/
https://www.fbo.gov/utils/view?id=1c871251d4f47d3cf30d40d64c7cc251

Rotate the 'scope 90 degrees and you have a thermal detector which directly reads vertical velocity. Presumably, if the system can be miniaturized to fit in a rifle scope and be powered by man-packable batteries, fitting it into a sailplane shouldn't be that difficult - costs aside.

son_of_flubber
October 24th 12, 01:03 AM
On Tuesday, October 23, 2012 7:26:38 PM UTC-4, Bill D wrote:

> http://www.accurateshooter.com/optics/new-wind-reading-lidar-laserscope/

I expect that this technology will be deployed on Skynet Drones (UAVs) before it reaches sailplanes.

Brad[_2_]
October 24th 12, 02:20 AM
On Oct 23, 5:03*pm, son_of_flubber > wrote:
> On Tuesday, October 23, 2012 7:26:38 PM UTC-4, Bill D wrote:
> >http://www.accurateshooter.com/optics/new-wind-reading-lidar-laserscope/
>
> I expect that this technology will be deployed on Skynet Drones (UAVs) before it reaches sailplanes.

I did some consulting work for a small company making VR headgear to
be used for training purposes. I mentioned to him about the
possibility of tweaking the device so that it would pick up
"thermals". He seemed to think it could be done.

Of course the display would need to be re-designed for our use, but it
sure would be cool. I suspect it isn't too far on the tech horizon for
us glider guiders.

Brad

Liam
October 24th 12, 04:32 AM
On Oct 23, 4:26*pm, Bill D > wrote:
> Even with PowerFLARM on "stealth" pilots may soon have another way to find the next thermal. *The DARPA "One Shot" initiative will develop a rifle scope which uses LIDAR to detect and correct for crosswind "windage". *The Israeli Soreq Nuclear Research Center has already been granted a patent on the LIDAR technology.
>
> http://www.accurateshooter.com/optics/new-wind-reading-lidar-laserscope/https://www.fbo.gov/utils/view?id=1c871251d4f47d3cf30d40d64c7cc251
>
> Rotate the 'scope 90 degrees and you have a thermal detector which directly reads vertical velocity. *Presumably, if the system can be miniaturized to fit in a rifle scope and be powered by man-packable batteries, fitting it into a sailplane shouldn't be that difficult - costs aside.

The Israeli solution, iirc, uses speckle backscatter from the target,
not aerosol backscatter, so you'd have to have a buddy fly about half
a kilometer beside you and look for thermals in between.

Roel Baardman
October 24th 12, 08:57 AM
My money would be on a Particle Image Velocimetry (PIV) based
solution.
Largely because this is technology which is extremely widely used
(every laser mouse does it in hardware).
I've heard about model airplanes using it to stabilize bank angle
(more speed = lower wing).

Roel

October 24th 12, 10:50 AM
On Wednesday, 24 October 2012 08:57:21 UTC+1, Roel Baardman wrote:
> My money would be on a Particle Image Velocimetry (PIV) based
> solution.
>
> Largely because this is technology which is extremely widely used
> (every laser mouse does it in hardware).

Optical mice use integrated circuits like the Agilent ADNS-2620:
http://www.datasheetcatalog.org/datasheet2/b/0frk4c7ofadgtuq5wccyqglz0hcy.pdf

So, unless you can form a 2D image of the particles'
velocity and have the ic process that image, I don't
see how you would do it.

> I've heard about model airplanes using it to stabilize bank angle
> (more speed = lower wing).

Quite possible. Many years ago I saw one of the
optical mice in the form or a ring on a finger.
With the appropriate focussing distance, the room
itself was used as a mouse pad.

waremark
October 24th 12, 11:35 AM
On Wednesday, October 24, 2012 10:50:01 AM UTC+1, wrote:
> On Wednesday, 24 October 2012 08:57:21 UTC+1, Roel Baardman wrote:
>
> > My money would be on a Particle Image Velocimetry (PIV) based
>
> > solution.
>
> >
>
> > Largely because this is technology which is extremely widely used
>
> > (every laser mouse does it in hardware).
>
>
>
> Optical mice use integrated circuits like the Agilent ADNS-2620:
>
> http://www.datasheetcatalog.org/datasheet2/b/0frk4c7ofadgtuq5wccyqglz0hcy..pdf
>
>
>
> So, unless you can form a 2D image of the particles'
>
> velocity and have the ic process that image, I don't
>
> see how you would do it.
>
>
>
> > I've heard about model airplanes using it to stabilize bank angle
>
> > (more speed = lower wing).
>
>
>
> Quite possible. Many years ago I saw one of the
>
> optical mice in the form or a ring on a finger.
>
> With the appropriate focussing distance, the room
>
> itself was used as a mouse pad.

Whatever the tech ultimately used to achieve this, what will it do to the sport? I know some people thought flight computers would ruin the sport, then GPS, then moving maps, but thus far it is still far from ruined. But visible thermals sounds like the biggest step yet towards reducing the challenge. What do others think?

Tony[_5_]
October 24th 12, 12:50 PM
On Wednesday, October 24, 2012 5:35:51 AM UTC-5, waremark wrote:
> On Wednesday, October 24, 2012 10:50:01 AM UTC+1, wrote:
>
> > On Wednesday, 24 October 2012 08:57:21 UTC+1, Roel Baardman wrote:
>
> >
>
> > > My money would be on a Particle Image Velocimetry (PIV) based
>
> >
>
> > > solution.
>
> >
>
> > >
>
> >
>
> > > Largely because this is technology which is extremely widely used
>
> >
>
> > > (every laser mouse does it in hardware).
>
> >
>
> >
>
> >
>
> > Optical mice use integrated circuits like the Agilent ADNS-2620:
>
> >
>
> > http://www.datasheetcatalog.org/datasheet2/b/0frk4c7ofadgtuq5wccyqglz0hcy.pdf
>
> >
>
> >
>
> >
>
> > So, unless you can form a 2D image of the particles'
>
> >
>
> > velocity and have the ic process that image, I don't
>
> >
>
> > see how you would do it.
>
> >
>
> >
>
> >
>
> > > I've heard about model airplanes using it to stabilize bank angle
>
> >
>
> > > (more speed = lower wing).
>
> >
>
> >
>
> >
>
> > Quite possible. Many years ago I saw one of the
>
> >
>
> > optical mice in the form or a ring on a finger.
>
> >
>
> > With the appropriate focussing distance, the room
>
> >
>
> > itself was used as a mouse pad.
>
>
>
> Whatever the tech ultimately used to achieve this, what will it do to the sport? I know some people thought flight computers would ruin the sport, then GPS, then moving maps, but thus far it is still far from ruined. But visible thermals sounds like the biggest step yet towards reducing the challenge. What do others think?

it will turn a flight that previously would've gone 300km into a 500km flight. would probably lead to a huge increase in the number of pilots flying cross country and in contests. records would start falling everywhere. i can't wait :)

Roel Baardman
October 24th 12, 01:58 PM
> Whatever the tech ultimately used to achieve this, what will it do
> to the sport? I know some people thought flight computers would
ruin > the sport, then GPS, then moving maps, but thus far it is
still far > from ruined. But visible thermals sounds like the
biggest step yet
> towards reducing the challenge. What do others think?

I think it actually doesn't matter what people think. Technology
will become available for the masses sooner or later, which will
challenge both pilots and contest organisers to think outside the
box.

Pilots will have to deal with more (sources of) information, and
will have to prioritize.
Contest organizers must find new ways to challenge pilots.

Besides this, the question is if remote detection will change the
field a lot. The same arguments hold for this as for the discussion
about powerFLARM I think.

Personally I am an aerobatic gliderpilot (and there's no tech for us
at all!), so this doesn't affect me directly. The only advantage is
that I can probably glide further when I decide to go cross-country
one day.

Roel Baardman
October 24th 12, 02:01 PM
> So, unless you can form a 2D image of the particles'
> velocity and have the ic process that image, I don't
> see how you would do it.

The particles moving inside a thermal are what I think you should
process. Little bugs lifting with the thermal, or even birds for a
start. Perhaps the curly movement of the cloud above the thermal in
the end?

If you can have some electronics spot that falcon circling a few miles
ahead in that killer thermal, this can already give you an advantage I
guess.

Tom Gardner[_2_]
October 24th 12, 02:37 PM
Roel Baardman wrote:
>> So, unless you can form a 2D image of the particles'
>> velocity and have the ic process that image, I don't
>> see how you would do it.

I should, of course, have referred to an image
of the particles, not of the particles' velocity.


> The particles moving inside a thermal are what I think you should
> process. Little bugs lifting with the thermal, or even birds for a
> start. Perhaps the curly movement of the cloud above the thermal in
> the end?
>
> If you can have some electronics spot that falcon circling a few miles
> ahead in that killer thermal, this can already give you an advantage I
> guess.

The ic bases its estimate of velocity on how fast points
are moving across its field of view. The field of view
is dependent on any aircraft movement, optical distortion
in the canopy, shadows. Removing the optical analogue of
"ground clutter" would also be necessary.

The resolution required to spot birds (let alone
"particles or bugs") at an interesting range
would be impressive.

Never say never, but I'd be interested to see the
false positive rate!

Roel Baardman
October 24th 12, 02:44 PM
> Never say never, but I'd be interested to see the false positive
rate!

I was merely approaching this from an academic viewpoint, and I agree
with the points you raise.

October 24th 12, 04:21 PM
>
> Whatever the tech ultimately used to achieve this, what will it do to the sport? I know some people thought flight computers would ruin the sport, then GPS, then moving maps, but thus far it is still far from ruined. But visible thermals sounds like the biggest step yet towards reducing the challenge. What do others think?


I wrote a short Soaring Magazine article a while ago, thinking about what thermal detectors might mean,

http://faculty.chicagobooth.edu/john.cochrane/soaring/docs/thermal_detectors.mht

or link from

http://faculty.chicagobooth.edu/john.cochrane/soaring/index.htm#corner

Short version: Even a wingspan range would make a huge difference. Flying airplanes without engines will never be easy. Thermal detectors could dramatically improve the sporting experience, as they could mean the end of gaggling, leeching, team flying, etc. And think about how nice it would be at the end of the day to know for sure that there aren't any thermals left so you'd better stop trying and land.

John Cochrane

Mike the Strike
October 24th 12, 04:36 PM
On a few occasions, I have observed soaring birds fly quickly towards a point where they found a thermal - sometimes a distance of about a kilometer. The speed and direction of them indicated to me that they were flying to an objective and not just hunting randomly. If so, this means that they can detect thermals remotely using their senses. If we can figure out how they are doing this, there is a chance we can build instruments to replicate their method.

Having studied the possibility of using electrostatic methods (thermals advect space charge from the ground and dust devils are actively charged by particle collision), this is very short range and not likely the mechanism birds are using. I would guess it has to be visual.

Mike

Bill D
October 24th 12, 05:01 PM
On Wednesday, October 24, 2012 9:36:48 AM UTC-6, Mike the Strike wrote:
> On a few occasions, I have observed soaring birds fly quickly towards a point where they found a thermal - sometimes a distance of about a kilometer.. The speed and direction of them indicated to me that they were flying to an objective and not just hunting randomly. If so, this means that they can detect thermals remotely using their senses. If we can figure out how they are doing this, there is a chance we can build instruments to replicate their method.
>
>
>
> Having studied the possibility of using electrostatic methods (thermals advect space charge from the ground and dust devils are actively charged by particle collision), this is very short range and not likely the mechanism birds are using. I would guess it has to be visual.
>
>
>
> Mike

I suspect it is visual for birds. The have far better vision than we and can probably see small objects like seeds rising with the thermal. They may also possess special visual processing centers in their brains evolved to detect thermals.

I suspect the "one shot" DARPA program works the same way by detecting embedded objects like dust and seeds moving across the field of view then using powerful algorithms to process the data. Range the objects as they move across the field and the direction and speed of the wind can be determined.

What's interesting to me is the comment that the device will work out to the maximum effective range of currently fielded sniper rifles. .50 caliber rifle ER's can exceed 3000 meters. There is also a comment elsewhere indicating the DOD wants to issue this to every soldier so it can't be too expensive.

John Firth[_3_]
October 24th 12, 07:13 PM
Forty years ago I put some effort into electrostatic
L/R detection of thermals. The big probelm is the vertical
component of the general gradient which is at least an order of magnitude
bigger than the horizontal part.
This meant that using tip mounted sensors, the vertical distance
between the tips times the vertical gradient would have to be
compensated for; these days with micro computers and roll rate
sensors,this might not be so difficult.
My approach was to mount probes fore and aft and try to fly
a constant pitch angle. (speed)

There were fields I could detect but never resulting in
finding a thermal by turning slowly L and R.
A real sucess was detecting a field across an airmass boundary
( a weak pseudo front, shown by haze) and confirmed by
several passes each direction. There was weak lift
but the haze variation gave this away and I only detected the
field as I flew through it.
The 25m plus spans of some gliders could allow a better
signal.

I await further initiatives with interest.

John Firth, old but no longer bold pilot.

>> On a few occasions, I have observed soaring birds fly quickly towards a
>p=
>oint where they found a thermal - sometimes a distance of about a
>kilometer=
>.. The speed and direction of them indicated to me that they were flying
>to=
> an objective and not just hunting randomly. If so, this means that they
>c=
>an detect thermals remotely using their senses. If we can figure out how
>t=
>hey are doing this, there is a chance we can build instruments to
>replicate=
> their method.
>>=20
>>=20
>>=20
>> Having studied the possibility of using electrostatic methods (thermals
>a=
>dvect space charge from the ground and dust devils are actively charged
by
>=
>particle collision), this is very short range and not likely the
mechanism
>=
>birds are using. I would guess it has to be visual.
>>=20
>>=20
>>=20
>> Mike
>
>I suspect it is visual for birds. The have far better vision than we and
>c=
>an probably see small objects like seeds rising with the thermal. They
>may=
> also possess special visual processing centers in their brains evolved
to
>=
>detect thermals.
>
>I suspect the "one shot" DARPA program works the same way by detecting
>embe=
>dded objects like dust and seeds moving across the field of view then
>using=
> powerful algorithms to process the data. Range the objects as they move
>a=
>cross the field and the direction and speed of the wind can be
determined.
>
>What's interesting to me is the comment that the device will work out to
>th=
>e maximum effective range of currently fielded sniper rifles. .50
caliber
>=
>rifle ER's can exceed 3000 meters. There is also a comment elsewhere
>indic=
>ating the DOD wants to issue this to every soldier so it can't be too
>expen=
>sive.
>

Bill D
October 24th 12, 07:54 PM
On Wednesday, October 24, 2012 12:15:03 PM UTC-6, John Firth wrote:
> Forty years ago I put some effort into electrostatic
>
> L/R detection of thermals. The big probelm is the vertical
>
> component of the general gradient which is at least an order of magnitude
>
> bigger than the horizontal part.
>
> This meant that using tip mounted sensors, the vertical distance
>
> between the tips times the vertical gradient would have to be
>
> compensated for; these days with micro computers and roll rate
>
> sensors,this might not be so difficult.
>
> My approach was to mount probes fore and aft and try to fly
>
> a constant pitch angle. (speed)
>
>
>
> There were fields I could detect but never resulting in
>
> finding a thermal by turning slowly L and R.
>
> A real sucess was detecting a field across an airmass boundary
>
> ( a weak pseudo front, shown by haze) and confirmed by
>
> several passes each direction. There was weak lift
>
> but the haze variation gave this away and I only detected the
>
> field as I flew through it.
>
> The 25m plus spans of some gliders could allow a better
>
> signal.
>
>
>
> I await further initiatives with interest.
>
>
>
> John Firth, old but no longer bold pilot.
>
>
>
> >> On a few occasions, I have observed soaring birds fly quickly towards a
>
> >p=
>
> >oint where they found a thermal - sometimes a distance of about a
>
> >kilometer=
>
> >.. The speed and direction of them indicated to me that they were flying
>
> >to=
>
> > an objective and not just hunting randomly. If so, this means that they
>
> >c=
>
> >an detect thermals remotely using their senses. If we can figure out how
>
> >t=
>
> >hey are doing this, there is a chance we can build instruments to
>
> >replicate=
>
> > their method.
>
> >>=20
>
> >>=20
>
> >>=20
>
> >> Having studied the possibility of using electrostatic methods (thermals
>
> >a=
>
> >dvect space charge from the ground and dust devils are actively charged
>
> by
>
> >=
>
> >particle collision), this is very short range and not likely the
>
> mechanism
>
> >=
>
> >birds are using. I would guess it has to be visual.
>
> >>=20
>
> >>=20
>
> >>=20
>
> >> Mike
>
> >
>
> >I suspect it is visual for birds. The have far better vision than we and
>
> >c=
>
> >an probably see small objects like seeds rising with the thermal. They
>
> >may=
>
> > also possess special visual processing centers in their brains evolved
>
> to
>
> >=
>
> >detect thermals.
>
> >
>
> >I suspect the "one shot" DARPA program works the same way by detecting
>
> >embe=
>
> >dded objects like dust and seeds moving across the field of view then
>
> >using=
>
> > powerful algorithms to process the data. Range the objects as they move
>
> >a=
>
> >cross the field and the direction and speed of the wind can be
>
> determined.
>
> >
>
> >What's interesting to me is the comment that the device will work out to
>
> >th=
>
> >e maximum effective range of currently fielded sniper rifles. .50
>
> caliber
>
> >=
>
> >rifle ER's can exceed 3000 meters. There is also a comment elsewhere
>
> >indic=
>
> >ating the DOD wants to issue this to every soldier so it can't be too
>
> >expen=
>
> >sive.
>
> >

In about that same time frame I worked on a set of paper charts showing data collected with an airplane traversing Mojave Desert thermals in mid-afternoon. The sensors included field mills for electrostatic charge and aerosol detectors in addition to the usual - temp, humidity etc.. The only consistent indicator of a 'thermal' was rising air. I think any successful remote thermal detector will have to "see" air motion directly.

soartech[_2_]
October 24th 12, 08:18 PM
Bill D wrote
> What's interesting to me is the comment that the device will work out to the maximum effective range of currently fielded sniper rifles. .50 caliber rifle ER's can exceed 3000 meters. There is also a comment elsewhere indicating the DOD wants to issue this to every soldier so it can't be too expensive.

Bill, please read Liam's comment above (4th message in thread). This
does not work for us. It requires firing a laser against a solid
target.

I have been studying this problem since 1984 and agree with all of
John Cochrane's points above. It will be good for soaring for the
reasons he cites and more. Just like GPS and all the other electronic
aids it will be rapidly accepted.
Technically, some passive or active (LASER or microwave) probing of
the clear atmosphere to detect the relative motion (subtracting your
vario) via backscatter from dust, bugs and pollen, along with image
processing algorithims, will probably be in the final solution.
I have compiled a database of relative papers on the technologies
involved here:
http://www.ct-hanggliding.org/thermal.htm but it's getting a little
old now as new things develop.
Looking forward to seeing someone finally make this happen.

Liam
October 24th 12, 09:22 PM
On Oct 24, 9:01*am, Bill D > wrote:
> On Wednesday, October 24, 2012 9:36:48 AM UTC-6, Mike the Strike wrote:
> > On a few occasions, I have observed soaring birds fly quickly towards a point where they found a thermal - sometimes a distance of about a kilometer. *The speed and direction of them indicated to me that they were flying to an objective and not just hunting randomly. *If so, this means that they can detect thermals remotely using their senses. *If we can figure out how they are doing this, there is a chance we can build instruments to replicate their method.
>
> > Having studied the possibility of using electrostatic methods (thermals advect space charge from the ground and dust devils are actively charged by particle collision), this is very short range and not likely the mechanism birds are using. *I would guess it has to be visual.
>
> > Mike
>
> I suspect it is visual for birds. *The have far better vision than we and can probably see small objects like seeds rising with the thermal. *They may also possess special visual processing centers in their brains evolved to detect thermals.
>
> I suspect the "one shot" DARPA program works the same way by detecting embedded objects like dust and seeds moving across the field of view then using powerful algorithms to process the data. *Range the objects as they move across the field and the direction and speed of the wind can be determined.
>
> What's interesting to me is the comment that the device will work out to the maximum effective range of currently fielded sniper rifles. *.50 caliber rifle ER's can exceed 3000 meters. *There is also a comment elsewhere indicating the DOD wants to issue this to every soldier so it can't be too expensive.

The patented Isreali system referenced in the article does not use
dust and seeds blown in the wind, it looks at the scinitllation of the
laser illuminated target due to the atmospheric turbulence blowing
across the line of sight. Sort of like the shimmering of a mirage.
It gives a path averaged crosswind speed from the observer to the
target.

Google