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-   -   the air forces know the secret for uber piloting the sports world doesnt (http://forum.fulqrumpublishing.com/showthread.php?t=34605)

Hood 09-30-2012 10:42 PM

Quote:

Originally Posted by raaaid (Post 465584)
yeas but for heavens sake how gullible you have to be to believe than an f16 stick has a six mm dead zone and havent you fly sims and know pretty well the dead zone issue, its ridicuolus

I'll try one last time.

The movement of the stick does not affect the control surfaces. The pressure on the stick causes the computer to determine the input to the control surfaces.

Now, you may say that to move the stick requires pressure so in fact the stick has no dead zone because any pressure that moves the stick also causes a control surface input. True it does, but the movement is based on the pressure and not the movement of the stick.


SIDE STICK VERSUS CONVENTIONAL CENTER STICK
Both the Hornet and Viper use fly-by-wire flight-control systems, which means aircraft response is governed by a set of programmed flight-control laws that "live" in the flight-control computers, which I affectionately refer to as "George." In other words, the pilot isn't flying the airplane, George is. The pilot tells George he wants the airplane to do something, and George then zips through the math to figure out which flight-control surfaces should be moved to fulfill the pilot's request. The big difference (and it is a big one) is that the Hornet uses a conventional center stick, and the computer senses stick position to interpret what the pilot wants. The Viper uses a side stick, and the computer senses stick force from pilot input.
Flying a side-stick control takes a while to get used to, but once you do, it's a joy. The conformal stick's shape feels very natural (it fits in the hand like a melted candy bar), and it allows easy access to nine of the 16 HOTAS controls. Two fully adjustable forearm rests on the right cockpit bulkhead stabilize and isolate the pilot's arm and wrist, so when rattling around the cockpit during turbulence or going after the bad guy, the pilot's arm won't accidentally move and initiate unwanted control inputs. In its original design, the Viper's control stick didn't move at all; it just measured pressure from the pilot's hand. However, after initial F-16 flight tests, a ¼ inch of stick movement was incorporated to give a small dead band and a nominal breakout force to give better "feel" of a neutral stick because otherwise it was entirely too sensitive. The control harmony is quite good (the pressures required for pitch and roll mix well), but without the capability to physically position the stick, it's easy to contaminate roll inputs with unwanted pitch inputs, and vice versa.

My first Viper instructor predicted that I would over-rotate on takeoff and drop the right wing; he was right. The over-rotation occurs because a pilot is used to "moving the stick and then something happens" at rotation speed. When I reached 145 knots and pulled back, of course the stick didn't move but a scant ¼ inch, so I pulled more. The inexperienced have no way of knowing how hard to pull, so I pulled probably twice as hard as was necessary.


"A Navy Test Pilot's Perspective" by Tougas, John Toonces "Flight Journal" Jun 03 Issue

raaaid 09-30-2012 11:00 PM

how do you explain that gogling side stick for an f16 and dead zone it only links here

https://www.google.es/#hl=en&sclient...pw.r_qf.&cad=b

Hood 09-30-2012 11:03 PM

Quote:

Originally Posted by raaaid (Post 465610)
how do you explain that gogling side stick for an f16 and dead zone it only links here

https://www.google.es/#hl=en&sclient...pw.r_qf.&cad=b

Because that's how Google's search engine works. Just because you can't find something at the first go doesn't mean it doesn't exist or that your intuition was right - it was wrong. Go and read some threads here - a great site that I used to visit a lot when playing Falcon 4:

http://www.f-16.net/

Hood

raaaid 09-30-2012 11:10 PM

the thing is that that f16 test pilot account using the word dead band for run confused the comunity

till now many people in the comunity believes the f16 stick is 6mm lose:rolleyes:

the f16 stick works as that pressure joystick i linked to

it says it REPLICATES an f16 sidestick

do you know what replicate means

for example do you know what a spit replica difference is with a real spit?

just the plate number ;)

Outlaw 10-01-2012 01:54 AM

Quote:

Originally Posted by raaaid (Post 465622)
the thing is that that f16 test pilot account using the word dead band for run confused the comunity

till now many people in the comunity believes the f16 stick is 6mm lose:rolleyes:

There is DEFINITELY a dead zone in the stick. Otherwise BREATHING on the stick would cause the control surfaces to move. And I mean that LITERALLY. A strain gauge at one end of a 24" long piece of 1/16" tk steel flat bar WILL measure the deflection CAUSED BY THE CHANGE IN TEMPERATURE DUE TO BREATHING ON THE OTHER END FOR LESS THAN A SECOND. I know b/c I've done it before. Now, as any idiot knows the F-16 stick will have 2 strain gauges to dampen temperature effects and the stick is insulated from most airflow but A DEAD ZONE IS REQUIRED on a force stick due to the extreme sensitivity of the devices.

Whether or not that dead zone is 3mm (fore/aft or port/starboard) of motion (or compensated for in the software) is irrelevant.

The point is that, in the F16, the 3mm of movement in a single direction DOES NOT MOVE THE CONTROL SURFACES TO 100% DEFLECTION. Nor is it the limit of measuring the force. So, after the 3mm has been reached, you are NOT EVEN CLOSE TO 100% INPUT. Now it may be that some amount of control input registers before the stick has stopped moving, but it is nowhere near the limit.

Additionally, as others have pointed out, the F-16 stick IS NOT EVEN CONNECTED TO THE CONTROL SURFACES. It's connected to the flight control computer only and the computer decides if the control surfaces should move or not (and how fast).

Furthermore, the gain (sensitivity) of the control inputs can be adjusted in flight. For example, when performing in-flight refueling the gain is set very low to smooth out the flying.


--Outlaw.

Outlaw 10-01-2012 02:00 AM

Quote:

Originally Posted by raaaid (Post 465068)
yes its the same than this


actually this is how an f16 joystick works:


http://www.realsimulator.com/html/fssb.html

From the website link YOU POSTED...

Quote:

During the last development phases we found that there was a big difference between the required pressure to fly with comfort and the high pressure that is required if you want to simulate the real thing.
It clearly states the BIG difference between the game stick AND THE REAL THING.

Here it is again...

Quote:

and the high pressure that is required if you want to simulate the real thing
100% proof that your graph is NOT an F-16 stick. It is the COUGAR MOD.

--Outlaw.

raaaid 10-01-2012 02:15 AM

well i understand you do this for fun, thats why i do it but your insults show where you get fun from

are you really an engineer or a lawyer?

one thing is a micrometric dead zone and a different what wjord monkey said whom you believe the WHOLE RUN AS DEATH ZONE



now you dont even understand english like when you say katy pery said thank you


The joystick barely moves replicating the displacement values of the real F-16 side stick controller. Similarly, the forces for maximum displacement are replicated although these can be reduced to suit personal preferences.

http://www.realsimulator.com/html/fssb.html

Outlaw 10-01-2012 02:56 AM

Quote:

Originally Posted by raaaid (Post 465678)
The joystick barely moves replicating the displacement values of the real F-16 side stick controller. Similarly, the forces for maximum displacement are replicated although these can be reduced to suit personal preferences.

http://www.realsimulator.com/html/fssb.html

4000 grams = 8.8 lbs.

The highest setting on the Cougar Mod is the, "17 to 25 pound". IF you make the assumption that this truly replicates an F-16 stick, your graph maxed at 4000 grams DOES NOT SHOW AN F-16 STICK.

There is no arguing that. So, your graph IS JUNK in the context of an F-16 stick.

Of course, none of that is relevant BECAUSE AS I SAID BEFORE, THE END OF TRAVEL DOES NOT MEAN THE END OF INPUT.

Of course, you don't understand that so it does not make any difference. Just for the record, I'm pretty sure that at least some of the bacteria in my lower intestines understand it by now.

Also, just for the record, I own a REPLICA of a 1965 Shelby Daytona. If I ever finish it mine will outperform the original by a significant margin. REPLICA (and replicate), DOES NOT MEAN EQUAL.

--Outlaw.

raaaid 10-01-2012 03:45 AM

so do you agree with fjord monkey statement?:

the whole 6 mm run of an f16 sidestick is dead zone

zander 10-01-2012 09:39 AM

Quote:

Originally Posted by raaaid (Post 465685)
so do you agree with fjord monkey statement?:

the whole 6 mm run of an f16 sidestick is dead zone

Actually it would have to be - unless they changed the whole stick after the complains - and added potis/hal sensors to the original force sensors. Doesn't sound too likely either.

Guess we need a field service manual.


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