wing levelers

"Predictor" wrote in message
oups.com...
Ernest Christley wrote:
"Dan, did you ever get a chance to work with fuzzy logic?"


Why overcomplicate things. This is just too easy an application with a
BasicX board and an accerleometer.

http://www.basicx.com/
http://www.analog.com/en/prod/0%2C28...L203%2C00.html

Couple this with a cheap GPS, and big servos modelled after the ones used in
RC aircraft (the BasicX computer is designed to drive them directly), and a
complete autopilot is an easy design project.

I;ve been playing with this for a while, but I'll admit i've spent more time
thinking than soldering.

Anybody seriously interested in teaming up?



Ron Webb..

Tim Ward suggested:
"And you might also want to google for:
Pease "fuzzy logic"

Bob Pease is a staff scientist at National Semiconductor. His
conclusions:
There is a tremendous amount of hype and outright falsehood, with very
little supporting data for the miracle applications.
It can help simplify some non-linear problems."


In this thread, the only strong claims made about fuzzy logic have been
that it is "risky" (which has gone unexplained) and that it is
non-deterministic, which is simply false.

Fuzzy logic has an extensive, published record of successful
applications on which to stand, both in control and elsewhere. I am
familiar with Bob Pease's criticism of certain published fuzzy control
applications, and he makes some good points. No one here, as I read
it, has made miraculous claims, nevertheless fuzzy logic has been used
to good effect to solve real-world problems.

You have apparently encountered some uncritical, starry-eyed fans of
fuzzy logic, for which you have my sympathy. Nonetheless, a technology
should be judged on its technical merits, not its adherents.


-Will Dwinnell
http://will.dwinnell.com

Ron Webb wrote:

"Predictor" wrote in message
oups.com...

Ernest Christley wrote:
"Dan, did you ever get a chance to work with fuzzy logic?"



Why overcomplicate things. This is just too easy an application with a
BasicX board and an accerleometer.

http://www.basicx.com/
http://www.analog.com/en/prod/0%2C28...L203%2C00.html

Couple this with a cheap GPS, and big servos modelled after the ones used in
RC aircraft (the BasicX computer is designed to drive them directly), and a
complete autopilot is an easy design project.

I;ve been playing with this for a while, but I'll admit i've spent more time
thinking than soldering.

Anybody seriously interested in teaming up?



Ron Webb..


Before anyone rushes into anything take if from someone who has worked
AFCS, stab aug and the like. I have been in rotor and fixed wing
aircraft when the systems have gone nuts during inflight ops checks.
Fortunately the systems could easily be overpowered manually and
disconnected either by a button on the stick grip.

In any event all the systems had a ton of engineering and flight testing
before being accepted for service.

On the other hand some of the nutso systems can be quite amusing in
hindsight. I had an H-3s aug system problem I couldn't duplicate on the
ground. I requested a flight. They sent me a pilot who had a habit of
placing his coffee cup on the floorboard near his foot. We hovered, he
engaged system which promptly went crazy. I'm standing in the back
looking over the FE's shoulder, holding on for dear life and collecting
dings and dents in my helmet. The pilot calmly reached down, picked up
his cup of coffee, took a swig, put it down and then disengaged. After
we disembarked I asked him why he had done that. He said something about
enjoying the ride. That was about 20 years ago. I still think it was a
bit funny

Dan, U.S. Air Force, retired

Dick

Check developments in Israel. They have a lot of UAV's that have
systems in them that might fit your requirement right off the shelf?

Big John
`````````````````````````````````````````````````` ``````


On Fri, 25 Feb 2005 00:12:06 GMT, "Dick" wrote:

Sitting around the hanger and discussing the possibility of somehow using
off-the-shelf electronic/computer components or gadgits for semi-automatic
wing leveling on lightly loaded, short wingspans.

Not being computer guys, the current thought is that something should be out
there that is available cheaply and modifiable to use a simple wing
leveler.

Having heard someplace that automotive computers, as an example, sense data
millions of times leads us to believe that sensing the wing tip initial
movement and counteracting very very quickly would be a good thing.

As an example: One fellow pictured a rolling ball bearing inside a tube
somehow activating a magnetic switch which in turn pulses a dc linear motor
to operate the aileron minutely.

We are not sure how to detect the very earliest initial wing tip movement or
drive the small trim type motor and would appreciate some thoughts or site
recommendations to investigate.

Thanks, Dick

"Dan, U.S. Air Force, retired" wrote in message
news:wtJWd.24485

In any event all the systems had a ton of engineering and flight testing
before being accepted for service.

Dan

I agree 100% that any amateur designed auto pilot would be a risky
proposition. That's one reason I'm still in the parts accumulation stage 2
years after I started thinking about it. The part I'm having the most
trouble finding is a couple of big brass BALLS ;^}

Control systems engineering is perhaps THE most feared course in any
undergrad EE program, and for good reason. It's not an easy subject.

Having said that, I think it can be done. My own precautions will include:


1) The servos are coupled to the controls with springs - easily overpowered
by the manual controls which are left in place. And of course a big red
"DISENGAGE" button on the stick.

2) Thorough testing using X-Plane simulator. I'll use a custom designed
interface between the autopilot and the simulator.. That's one reason I'd
want more than one person on the project - the simulator test "pilot" should
be independant of the designer.

3) All control equasions will be radically over-damped. No "Auto-Pilot
Induced Oscillations".

4) The pitch control will only be controlling the trim tab.

More than 'just a wing leveler'
http://www.trioavionics.com/

On Sun, 6 Mar 2005, Ron Webb wrote:


Why overcomplicate things. This is just too easy an application with a
BasicX board and an accerleometer.
snipped
Anybody seriously interested in teaming up?


I started one, but then found a Navaid too cheap to pass up.
I bought the BX24 development kit, and had a great time programming
it to read the autopilot signal from my Terra, and then the NEMA code
from my GPS, but I got the navaid before buying a gyro.

Many pilots are upgrading the Navaid to a Trio solid state unit.

I can tell you that an acceleation chip reads nothing in the air.

There is some freeware for an altitude hold.

George Graham
RX-7 Powered Graham-EZ, N4449E
Homepage http://bfn.org/~ca266

Blueskies wrote:


More than 'just a wing leveler'
http://www.trioavionics.com/



If I were me I'd go with something like that rather than homebrew. My
main objection is its panel gulping size. It would be nice to have a
gyro/accelerometer package elsewhere and a small panel you can pace as
you please.

Dan, U.S. Air Force, retired

Dan, U.S. Air Force, retired wrote:

Blueskies wrote:


More than 'just a wing leveler'
http://www.trioavionics.com/



If I were me I'd go with something like that rather than homebrew.
Myaccommodatejection is its panel gulping size. It would be nice to have a
gyro/accelerometer package elsewhere and a small panel you can pace as
you please.

Dan, U.S. Air Force, retired


I don't know Dan you must be flying a pretty tight plane. The unit
referenced is only 3.25" square by 2.75" deep for the panel mount part, the
servo which isn't panel mounted is a bit bigger. Most homebuilts can
accommodate that. Now all I need to do is get to work on this KR-2 in the
garage!
John

UltraJohn wrote:
Dan, U.S. Air Force, retired wrote:


Blueskies wrote:


More than 'just a wing leveler'
http://www.trioavionics.com/



If I were me I'd go with something like that rather than homebrew.

Myaccommodatejection is its panel gulping size. It would be nice to have a

gyro/accelerometer package elsewhere and a small panel you can pace as
you please.

Dan, U.S. Air Force, retired



I don't know Dan you must be flying a pretty tight plane. The unit
referenced is only 3.25" square by 2.75" deep for the panel mount part, the
servo which isn't panel mounted is a bit bigger. Most homebuilts can
accommodate that. Now all I need to do is get to work on this KR-2 in the
garage!
John


I'm building an airplane I personally will never fly (can't pass the
physical). The only thing I could do to install the system in question
is remove the TAS indicator.

Dan, U.S. Aie Force, retired