| T.R | Title | User | Personal
Name | Date | Lines |
|---|
| 532.8 | | SPKALI::THOMAS | | Thu Oct 15 1987 15:42 | 7 |
|
To continue the chopper talk I,ve decided to run two batteries
in my set up. I have a spare 800ma. pack at home so I plan to run
the gyro on the 800ma pack and a 500ma. pack for the radoi.
COMMENTS?
Tom
|
| 532.1 | Gyro answers. | MDSUPT::EATON | Dan Eaton | Fri May 06 1988 16:03 | 29 |
|
> What do they use for a sensor?
> Where do they hook up (in terms a non-chopper pilot can grok)?
> I'm thinking of adding something to Tycho so he will stop and await
> further instructions if pitch or roll angle get beyond a certain
> point. I'd also like to get feedback from him in terms of roll,
> pitch, and heading, and thought a chopper gyro might be a good place
> to start. Any other ideas?
> Willie
Hi Willie,
I've never had mine apart to look at the gory details, but from the pictures
I've seen and the sound it makes I think there's a small motor driven gyroscope
inside.
Their use on helicopters has been to correct the large swings in the tail boom
caused by changes in torque on the rotor head. At least on the GMP unit you
hook them up by pulling the plug for the tail rotor servo out of the reciever,
plugging in the gyro in it's place, and then plugging the servo into the gyro.
Note that the gyro reacts to changes in position.
From your description of what you want, it sounds like you need something more
in the order of a ball-in-track tilt indicator than a gyro. That would let you
know the bank you are starting down is getting steeper.
Dan Eaton
|
| 532.2 | I know, a marine autopilot! :+} | SNDCSL::SMITH | William P.N. (WOOKIE::) Smith | Sat May 07 1988 11:07 | 7 |
| Thanks Dan. I was thinking worst-case I could just hang a weight
on a Radio Shack joystick (held upside down of course) and read
roll and pitch from the pots, or just encode them with a standard
R/C encoder chip and ship them back to the base. Any ideas for
a heading indicator?
Willie
|
| 532.3 | Another (simpler) idea... | RICKS::MINER | | Wed May 11 1988 12:59 | 27 |
| Willie,
As I was drifting off to sleep last night I got an idea that should
work great for your needs: use mecury switches for the tilt sensors.
Mecury switches are a little glass tube with a wire sticking in
each end and a ball of mecury inside the tube. It looks something
like this: ________________________
/ \
--------- -------------------------
\________________________/
Note that the gap between the 2 wires is NOT centered but is near
one end. Thus, when the tube tips to the left, the merury ball
makes contact and when the tube tips right, contact breaks.
These switches could be mounted at the angles you want to safeguard
against. They could be set up to be normally "closed" and wired
in series and used to cut motor and/or Rx power. Or, the could
be set normally "open" and wired in parellel and fed into whatever
electronics you planned to use for the joystick.
Of course, my idea is only good for the "Stop_If_Too_Steep" idea
is the only one that you are interested in. If you actually want
to send the angle data back to base camp then the joystick is best.
- Dan Miner
|
| 532.4 | Clever! | SNDCSL::SMITH | William P.N. (WOOKIE::) Smith | Wed May 11 1988 18:13 | 9 |
| Dan,
Thanks, I like it! I'm familiar with mercury switches, just
never thought of them for tilt/pitch limit switches. I'll have
to look into it.
Thanks,
Willie
|
| 532.5 | The price was right! | SNDCSL::SMITH | William P.N. (WOOKIE::) Smith | Mon May 16 1988 19:26 | 11 |
| Someone gave me a gyro and it is indeed a motor-driven flywheel in a
springloaded mount with one axis of freedom. Essentially it ends up
being a yaw rate sensor. The one I have is a Kraft Systems, Inc. gyro
with a magnet mounted on the motor and what looks to be a hall-effect
bridge for reading position. It has a separate box with most of the
electronics in it (one chip, 6 transistors, 4 pots and 'several'
passives). One pot is externally adjustable and labeled "sensitivity".
I haven't hooked it up to a servo yet (wrong connectors), but I kind of
doubt this is what I'm looking for...
Willie
|
| 532.6 | A Kraft byany other name... | MDSUPT::EATON | Dan Eaton | Tue May 17 1988 12:13 | 7 |
| Hi Willie,
The gyro you have is the same one I have. It used to be known as
the Kraft gyro. GMP now imports it so of course they renamed it
to the GMP gyro. If you can't use it and its up for sale let me
know.
Dan Eaton
|
| 532.7 | Noisy little thing! | SNDCSL::SMITH | William P.N. (WOOKIE::) Smith | Tue May 17 1988 19:33 | 12 |
| Dan,
I tried it out last night and it doesn't seem to work. I tried
various combinations of input/output cables (I had to change the
connectors and I wasn't too clear on what which was which) and it
doesn't do anything. I'm not sure what I should do with it, if
I could get schematics I'd probably try (someday) to fix it but
maybe I'll just toss it on the shelf. It was a donation and I'm
not sure I can dispose of it.... Maybe I only blew out the output
driver, so I might be able to use the motor and sensor...
Willie
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