NASA model uses thermals

[Burt Compton - Marfa]

"Robot Plane Can Find Thermals to Stay Aloft"

(Oct 6, 2005) NASA engineers tested out a prototype unmanned sailplane
this week at the Dryden Flight Research Center in California. This
robotic aircraft is capable of detecting and using rising air thermals,
similar to a glider or bird, to gain altitude. It launched from the
ground, and navigated to a likely location for updrafts. Once it found
a thermal, it turned off its engine and circled to stay within the
updraft. NASA hopes to develop techniques for using thermals that could
extend the range of unmanned aerial vehicles that often have very
limited fuel.

With the graceful flight of hawks and eagles in mind, NASA aerospace
engineer Michael Allen recently hand-launched a 15-pound motorized
model sailplane over the Southern California desert. He was hoping it
would catch plumes of rising air called thermals.

The sailplane did just that several times without human intervention
during a series of research flights at NASA's Dryden Flight Research
Center, Calif. The tests validated Allen's premise that using thermal
lift could significantly extend the range and flight endurance of small
unmanned air vehicles. Thermal lift increases vehicle endurance and
saves fuel. This is significant, as small vehicle flight duration is
often restricted by limited fuel capacity.

Allen and his team of engineers and technicians flew the
remote-controlled RnR Products sailplane 17 times from July through
mid-September. The sailplane was modified by Dryden aerospace
technicians to incorporate a small electric motor and an autopilot
programmed to detect thermals.

The 14-foot-wingspan model flew to an altitude of about 1,000 feet. The
ground-based remote control pilot then handed off control to the
sailplane's onboard autopilot. The autopilot software flew the plane on
a pre-determined course over the northern portion of Rogers Dry Lake at
Edwards Air Force Base, Calif., until it detected an updraft. As the
aircraft rose with the updraft, the engine automatically shut off. The
aircraft circled to stay within the lift from the updraft.

Allen said the small sailplane added 60 minutes to its endurance by
autonomous thermal soaring. The modified sailplane gained an average
altitude in 23 updrafts of 565 feet, and in one strong thermal ascended
2,770 feet.

"The flights demonstrated a small unmanned vehicle can mimic birds and
exploit the free energy that exists in the atmosphere," Allen said. "We
have been able to gather useful and unique data on updrafts and the
response of the aircraft in updrafts. This will further the technology
and refine the algorithms used."

Small, portable, unpiloted, long-endurance vehicles could fulfill a
number of observation roles including forest fire monitoring, traffic
control, search and rescue.

For more information about flight research at Dryden on the Web visit:
http://www.nasa.gov/centers/dryden

For information about NASA and agency programs on the Web, visit:
http://www.nasa.gov/home

Original Source: NASA News Release

[Paul Remde]

Hi,

That is very interesting.

I'm surprised that it gained so little altitude in the thermals. Does that
imply that the automatic thermal centering autopilot did not do a good job?

Paul Remde

"Burt Compton - Marfa" > wrote in message
oups.com...
> "Robot Plane Can Find Thermals to Stay Aloft"
>
> (Oct 6, 2005) NASA engineers tested out a prototype unmanned sailplane
> this week at the Dryden Flight Research Center in California. This
> robotic aircraft is capable of detecting and using rising air thermals,
> similar to a glider or bird, to gain altitude. It launched from the
> ground, and navigated to a likely location for updrafts. Once it found
> a thermal, it turned off its engine and circled to stay within the
> updraft. NASA hopes to develop techniques for using thermals that could
> extend the range of unmanned aerial vehicles that often have very
> limited fuel.
>
> With the graceful flight of hawks and eagles in mind, NASA aerospace
> engineer Michael Allen recently hand-launched a 15-pound motorized
> model sailplane over the Southern California desert. He was hoping it
> would catch plumes of rising air called thermals.
>
> The sailplane did just that several times without human intervention
> during a series of research flights at NASA's Dryden Flight Research
> Center, Calif. The tests validated Allen's premise that using thermal
> lift could significantly extend the range and flight endurance of small
> unmanned air vehicles. Thermal lift increases vehicle endurance and
> saves fuel. This is significant, as small vehicle flight duration is
> often restricted by limited fuel capacity.
>
> Allen and his team of engineers and technicians flew the
> remote-controlled RnR Products sailplane 17 times from July through
> mid-September. The sailplane was modified by Dryden aerospace
> technicians to incorporate a small electric motor and an autopilot
> programmed to detect thermals.
>
> The 14-foot-wingspan model flew to an altitude of about 1,000 feet. The
> ground-based remote control pilot then handed off control to the
> sailplane's onboard autopilot. The autopilot software flew the plane on
> a pre-determined course over the northern portion of Rogers Dry Lake at
> Edwards Air Force Base, Calif., until it detected an updraft. As the
> aircraft rose with the updraft, the engine automatically shut off. The
> aircraft circled to stay within the lift from the updraft.
>
> Allen said the small sailplane added 60 minutes to its endurance by
> autonomous thermal soaring. The modified sailplane gained an average
> altitude in 23 updrafts of 565 feet, and in one strong thermal ascended
> 2,770 feet.
>
> "The flights demonstrated a small unmanned vehicle can mimic birds and
> exploit the free energy that exists in the atmosphere," Allen said. "We
> have been able to gather useful and unique data on updrafts and the
> response of the aircraft in updrafts. This will further the technology
> and refine the algorithms used."
>
> Small, portable, unpiloted, long-endurance vehicles could fulfill a
> number of observation roles including forest fire monitoring, traffic
> control, search and rescue.
>
> For more information about flight research at Dryden on the Web visit:
> http://www.nasa.gov/centers/dryden
>
> For information about NASA and agency programs on the Web, visit:
> http://www.nasa.gov/home
>
> Original Source: NASA News Release
>

[Bill Daniels]

"Burt Compton - Marfa" > wrote in message
oups.com...
> "Robot Plane Can Find Thermals to Stay Aloft"
>
> (Oct 6, 2005) NASA engineers tested out a prototype unmanned sailplane
> this week at the Dryden Flight Research Center in California. This
> robotic aircraft is capable of detecting and using rising air thermals,
> similar to a glider or bird, to gain altitude. It launched from the
> ground, and navigated to a likely location for updrafts. Once it found
> a thermal, it turned off its engine and circled to stay within the
> updraft. NASA hopes to develop techniques for using thermals that could
> extend the range of unmanned aerial vehicles that often have very
> limited fuel.
>
> With the graceful flight of hawks and eagles in mind, NASA aerospace
> engineer Michael Allen recently hand-launched a 15-pound motorized
> model sailplane over the Southern California desert. He was hoping it
> would catch plumes of rising air called thermals.
>
> The sailplane did just that several times without human intervention
> during a series of research flights at NASA's Dryden Flight Research
> Center, Calif. The tests validated Allen's premise that using thermal
> lift could significantly extend the range and flight endurance of small
> unmanned air vehicles. Thermal lift increases vehicle endurance and
> saves fuel. This is significant, as small vehicle flight duration is
> often restricted by limited fuel capacity.
>
> Allen and his team of engineers and technicians flew the
> remote-controlled RnR Products sailplane 17 times from July through
> mid-September. The sailplane was modified by Dryden aerospace
> technicians to incorporate a small electric motor and an autopilot
> programmed to detect thermals.
>
> The 14-foot-wingspan model flew to an altitude of about 1,000 feet. The
> ground-based remote control pilot then handed off control to the
> sailplane's onboard autopilot. The autopilot software flew the plane on
> a pre-determined course over the northern portion of Rogers Dry Lake at
> Edwards Air Force Base, Calif., until it detected an updraft. As the
> aircraft rose with the updraft, the engine automatically shut off. The
> aircraft circled to stay within the lift from the updraft.
>
> Allen said the small sailplane added 60 minutes to its endurance by
> autonomous thermal soaring. The modified sailplane gained an average
> altitude in 23 updrafts of 565 feet, and in one strong thermal ascended
> 2,770 feet.
>
> "The flights demonstrated a small unmanned vehicle can mimic birds and
> exploit the free energy that exists in the atmosphere," Allen said. "We
> have been able to gather useful and unique data on updrafts and the
> response of the aircraft in updrafts. This will further the technology
> and refine the algorithms used."
>
> Small, portable, unpiloted, long-endurance vehicles could fulfill a
> number of observation roles including forest fire monitoring, traffic
> control, search and rescue.
>
> For more information about flight research at Dryden on the Web visit:
> http://www.nasa.gov/centers/dryden
>
> For information about NASA and agency programs on the Web, visit:
> http://www.nasa.gov/home
>
> Original Source: NASA News Release
>

Model sailplane guys have been experimenting with thermal centering
'autopilots' for some time. I suspect NASA's project is an outgrowth of
that. There's a lot of technology exchange between the UAV community and
the Radio Controlled aircraft hobby people. The RC guys are amazing
technologists.

Anyone who has used a thermal centering aid knows that it works - some of
the time. It seems to work best in classic, smooth thermals and not so well
in the chaotic, turbulent thermals of the high mountains of the US west.

What I expect to eventually see is flocks of stealthy, autonomous
motorglider-like soaring UAV's that share information about lift locations
and use that information to stay aloft over an area of military interest for
long periods. That might lead to a new market for glider manufacturers and,
in turn, lead to much lower production costs. (Anybody know of a large
purchase of motorgliders by the US government?)

I hope this doesn't set off the luddites. Thermal centering aids haven't
made instant champions out of pilots with lesser skills. I doubt that
technology will ever do that.

Bill Daniels

[Eric Greenwell]

Bill Daniels wrote:

>
> What I expect to eventually see is flocks of stealthy, autonomous
> motorglider-like soaring UAV's that share information about lift locations
> and use that information to stay aloft over an area of military interest for
> long periods. That might lead to a new market for glider manufacturers and,
> in turn, lead to much lower production costs. (Anybody know of a large
> purchase of motorgliders by the US government?)

Not a large purchase, but maybe a start: a University has ordered two
SparrowHawks for UAV research, with deliveries schelduled "soon".


--
Change "netto" to "net" to email me directly

Eric Greenwell
Washington State
USA

[Frank Whiteley]

Website says three for UAV research. Georgia Tech maybe? Happen to
know an undergraduate that's focusing on UAV's there.

Frank Whiteley

[Chris Nicholas]

With NASA and military interest in thermals, and the resources they have
to throw at the issues, what are the chances of reviving ideas for a
remote thermal detector system?

Simulations showed it could turn a typical UK blue day into a
record-breaker if thermals could be successfully detected at a distance.

The UK person working on it was unable to complete the development, but
I heard from other people (mainly in the USA) that similar thoughts had
been in circulation over there.

For purists, it could always be turned off or banned for
comps./records - and we could always go back to the primary glider vs
hot ship for silver etc. argument, for those minded to object to
technology advancing. (Again.)

Chris N.






__________________________________________________ _________
Yahoo! Messenger - NEW crystal clear PC to PC calling worldwide with voicemail http://uk.messenger.yahoo.com

[Jim Vincent]

"Chris Nicholas" > wrote in message
...

>
> Simulations showed it could turn a typical UK blue day into a
> record-breaker if thermals could be successfully detected at a distance.
> >
> Chris N.
>
And that would take all the wonder from this great sport...might as well fly
power.

[Bill Daniels]

"Chris Nicholas" > wrote in message
...
> With NASA and military interest in thermals, and the resources they have
> to throw at the issues, what are the chances of reviving ideas for a
> remote thermal detector system?
>
> Simulations showed it could turn a typical UK blue day into a
> record-breaker if thermals could be successfully detected at a distance.
>
> The UK person working on it was unable to complete the development, but
> I heard from other people (mainly in the USA) that similar thoughts had
> been in circulation over there.
>
> For purists, it could always be turned off or banned for
> comps./records - and we could always go back to the primary glider vs
> hot ship for silver etc. argument, for those minded to object to
> technology advancing. (Again.)
>
> Chris N.
>
I see two problems with remote thermal detection. The first is that
thermals are fleeting phenomenon which, if detected at a large distance,
wouldn't be there when the glider arrived. The second is that the most
consistent distinguishing feature of thermals by far is simply rising air.

Rising air can be remotely detected with LIDAR as evidenced by several
research papers on thermal plumes in the planetary boundary layer. LIDAR,
however, isn't very stealthy and only works at fairly short ranges - at
least with the power available in a small UAV.

Even low-power LIDAR might be somewhat effective in enhancing performance.
A short-range, (100m)low-power on-board LIDAR air motion detection system
that could reliably indicate the correct direction to turn or, once
circling, the correct direction to move the circle might be possible.
Dolphin flying zooms reliably begun 2 - 3 seconds in advance of strong
thermals would dramatically increase inter-thermal cruising speeds.

Perhaps a much larger aircraft or satellite orbiting far above a military
theater of interest with a powerful down-looking LIDAR could locate thermals
and relay their position to a swarm of soaring UAV's below.

Bill Daniels

[[email protected]]

Do you avoid flying under cloud streets, because it's no fun to know
where the lift is?

[Jim Vincent]

> wrote in message
oups.com...
> Do you avoid flying under cloud streets, because it's no fun to know
> where the lift is?
>

What's a cloud? Streets are at gound level.

[COLIN LAMB]

We already have remote thermal detection.

Just find out who is flying and follow the best pilot out and get underneath
him. Be wary, though, if he has a better glide ratio than you and sucks you
away from the field. It pays to suck up to him on occasion. Maybe wash his
windshield or help him disassemble his ship.