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leitmotiv
09-08-2006, 04:13 AM
As I understand, there was no automatic centering in real aircraft sticks until after WWII (thus, I disengaged my stick's self-centering). My question is simple---when was this introduced, and was it universally adopted? I have noticed flying modern jets without self-centering is (1) arduous, and (2) a good way to dig a deep well with your jet. Thanks.

widdershins
09-08-2006, 04:26 AM
The real life pilots here would know better, but the 1st thing I noticed when I had the opportunity
to fly a Piper Colt a while back was that while in flight, the yoke did center on its own. I never asked the pilot about this because I has assumed it was due to the airflow over the contol surfaces. On the ground however, it seemed to stay where I left it.
As for modern jets, most if not all employ fly by wire technology... therefore the stick is literally a joystick just like you use on your computer, albeit a considerably more expensive/robust one.

WB_Outlaw
09-08-2006, 06:52 AM
In a real aircraft with direct connections to the control surfaces, aerodynamic forces will "center" the stick if it is released. This is called "stick free". Note that this "center", is NOT a zero deflection of the control surfaces. The airspeed, trim, and design will determine the stick free "center".

Since our joystick deflections determine the amount of force applied to the virtual stick and not the amount of control surface deflection, I can't think of any reason NOT to have it self center.

Some modern fly by wire aircraft don't use a joystick at all. They use a force stick, which does not deflect at all. Strain gauges measure the amount of force applied by the pilot instead of the amount of deflection.

--Outlaw.

leitmotiv
09-08-2006, 07:52 AM
I see I apparently misinterpreted a posting from WWSensei on 12 June 2006:

"One possibility is if you have a self-centering joystick then when you let it go the joystick will self-center and send inputs to the game to do the same. The problem is your use of an improper control stick (real ones don't self-center llike PC joysticks) not the game.

"When I fly FS9 I tend to use a non-self centering control yoke and FS9 behaves accordingly."

widdershins
09-08-2006, 09:13 AM
Originally posted by WB_Outlaw:
Some modern fly by wire aircraft don't use a joystick at all. They use a force stick, which does not deflect at all. Strain gauges measure the amount of force applied by the pilot instead of the amount of deflection.

--Outlaw.
Cool!

These board are better than Schoolhouse Rocks sometimes.

rnzoli
09-08-2006, 03:10 PM
Strain gauges measure the amount of force applied by the pilot instead of the amount of deflection.

I heard some top Cougar stick mods do exactly the same and you are able to fly this way in IL2 as well.

WB_Outlaw
09-08-2006, 10:35 PM
Originally posted by rnzoli:
I heard some top Cougar stick mods do exactly the same and you are able to fly this way in IL2 as well.

Yes, there is at least one force stick mod out there for the Cougar but I don't know if the guy is still makin' 'em. When my Cougar quit working after it impacted against the wall (musta hit a stud), I replaced it with a X-52 (will break just gettin' close to a wall) so I haven't kept up with the Cougar crowd.

I tried building a force stick with some strain gauges a buddy had from his old gig, but, the problem is that the change in the strain gauge's resistance is VERY, VERY, VERY small with force. It requires a Wheatstone bridge and an amplifier circuit to get the 5 volts a controller expects. I got the bridge built (voltag changes were in the 1/10000 range) but the amplifier stumped me. It should be as simple as snagging a $1 op-amp from Radio Shack but after a couple of hours of messin' with it everything suddenly impacted with the wall and I gave up.

Bodnar sells a version of his controller with one analog axis input setup with the bridge and an amp. Unfortunately, you need two axes for a stick so it's kind of useless. There is another guy (I forget who but it's in the stick modders thread) who makes a more expensive controller that has a gazillion inputs of all types, including force stick. It's not cheap though.

I'll shut-up now.

--Outlaw.

NonWonderDog
09-08-2006, 11:24 PM
Originally posted by widdershins:
As for modern jets, most if not all employ fly by wire technology... therefore the stick is literally a joystick just like you use on your computer, albeit a considerably more expensive/robust one.

I'm sure this will seem like over-engineered nonsense at first, but joysticks like that have sophisticated force-feedback systems built in. They're in every way set up to feel exactly as if they were connected to the control surfaces by cable. The only differences are the limiters and the fact that the maximum forces required to pull the stick are often rather less than if you were using arm power alone.

I believe, however, that the only currently operational big commercial jets with digital fly-by-wire controls are Airbus models from the A320 up. The Boeing 777 will be fly-by-wire, as well. Most of the others just have hydraulically boosted controls.

The-Pizza-Man
09-09-2006, 12:24 AM
The F-16's sidestick doesn't move except for a small bit of play that establishes a deadzone. Other than that they don't move at all they just measure the force being applied by the pilot. I think the F-22 and F-35 have the same set up.

leitmotiv
09-09-2006, 12:30 AM
I thought force feedback was an absolutely necessary bit of fakery, NonWonderDog, until I added the Capt Brown settings to the mix on my Logitech Wingman 3D---after that I was brawling with my stick and the enemy. But, having recently acquired a new unused Microsoft Sidewinder 2 FF stick---good grief---force feedback has taken on a new dimension. I don't even need the Capt Brown settings---the stick is a beast to use. It really needs to be anchored to the table with heavy bolts. When I took it off self-centering on advice of WWSensei, it became even more arduous. I love it. Beats bench pressing weights.

NonWonderDog
09-09-2006, 09:01 AM
Ah!

If you have a force feedback stick, ABSOLUTELY disable self-centering. The stick will center itself just due to the force feedback effects, and turning on the artificial centering will kill the feel of the force feedback. This goes for any game that has even semi-realistic force feedback.

But I really was saying that the real A320 controls are force-feedback. They have motors on them to simulate "feel" and allow the pilot to trim normally. It's the same with every commercial fly-by-wire plane. It's only a couple US Air Force fighters that have pressure sticks.

leitmotiv
09-09-2006, 09:34 AM
Fascinating!

Akronnick
09-09-2006, 10:31 PM
Originally posted by WB_Outlaw:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by rnzoli:
I heard some top Cougar stick mods do exactly the same and you are able to fly this way in IL2 as well.

Yes, there is at least one force stick mod out there for the Cougar but I don't know if the guy is still makin' 'em. When my Cougar quit working after it impacted against the wall (musta hit a stud), I replaced it with a X-52 (will break just gettin' close to a wall) so I haven't kept up with the Cougar crowd.

I tried building a force stick with some strain gauges a buddy had from his old gig, but, the problem is that the change in the strain gauge's resistance is VERY, VERY, VERY small with force. It requires a Wheatstone bridge and an amplifier circuit to get the 5 volts a controller expects. I got the bridge built (voltag changes were in the 1/10000 range) but the amplifier stumped me. It should be as simple as snagging a $1 op-amp from Radio Shack but after a couple of hours of messin' with it everything suddenly impacted with the wall and I gave up.

Bodnar sells a version of his controller with one analog axis input setup with the bridge and an amp. Unfortunately, you need two axes for a stick so it's kind of useless. There is another guy (I forget who but it's in the stick modders thread) who makes a more expensive controller that has a gazillion inputs of all types, including force stick. It's not cheap though.

I'll shut-up now.

--Outlaw. </div></BLOCKQUOTE>

Seems like your hardware has issues with the wall, how does this keep happening?