I am tossing around the idea of hand-hacking a set of rudder pedals from a controller I bought that’s a plastic Piece Of Junk with workable electronics.
IRL, do they just flop around, or should they self center to some degree?
How strongly should they resist motion, especially from the centered position?
Thanks!
The pedals are connected to the rudder. As airspeed increases, the airflow on either side of the rudder will act to centre it with increasing force. So in that sense, rudder pedals self-centre. As for “flopping around”, no, nothing flops around, even on the ground. There are too many mechanical links involved for that.
As @CommanderTin said, the centering force is an aerodynamic force, not a spring, but all flighsim rudder pedals, lacking force feedback, use a spring to simulate the effect. The MFG Crosswind even supplies different cams to adjust the feel as deflection increases.
This is exactly correct. The caveat is that the rudder is trimmed for a particular angle of attack, so it will try to align based on how it’s trimmed, just like an elevator, even some ailerons. Some aircraft have rudder trim that is adjustable in flight, some only on the ground, and some not at all.
The “centered” trim/AoA occurs in a very narrow speed band (usually cruise), so it gets out of trim above or below that (and again, some can be adjusted in flight. It may not move much, but it may not exactly be dead-center and if you were to try to find the physical center of pedal travel, you might feel a little more pressure on one leg or the other.
But there isn’t a clicky center-stop like found on most gaming systems. I actually put a couple Velcro strips under the rollers inside my pedals so they don’t automatically self-center. This isn’t exactly realistic, either, but it keeps me on my toes, pun intended.
Anyway, the centering mechanisms of our yokes, sticks, gamepads, pedals, etc, do us some disservice to that effect. Other than spatial proprioception and disorientation, control pressure/feedback is the biggest realism hurdle in the sim.
In addition what everyone has correctly said, helicopter pedals typically do not center, they stay where you leave them even in flight.
A little complicated to do an areodynamics course …
Control surfaces activated by hydraulic power return to servo command neutral point on ground and in flight , for others the control surface remains where the pedals are on ground and where the neutral is determined by trim due to aerodynamic forces on the control surface in flight.
Hydraulic controls have a speed-dependent force hardening system that has no effect on neutral position , only on effort to apply on pedals or control column .
How it works depends on the aircraft. In some the only centering force is the airflow over the rudder. So no airflow they Flop left or right freely.
On other aircraft there is a bungee system to center the rudder.
The amount of force needed depends on many things….not least of which is the size and speed of the aircraft.
Then there is the linkeage between pedals and rudder….also very different setups in different aircraft.
In some the rudder was linked to the aileron to ease workload of the pilot.
And lastly there are different types of control boost.
The rudder in a C-150/152 is very light at almost any speed and easy to overcontrol for a newbie pilot.
The C-210s I flew required relatively strong forces at any speed but that was one of the bungee systems I believe. But the rudder trim on the bigger Cessna aircraft is easy to use and makes it almost as often used as horizontal trim.
Our Saratoga definitely had some form of bungee system to center the rudder and give a slightly heavier feel than you would have without it. But that also made it less likely to overcorrect and swing the tail around….with the long fuselage compared to the smaller Cherokee types the third row passengers appreciate that I think. The trim knob on the Saratoga was the only thing I never grew to like in almost 1000h flying that airplane. Location and use just far inferior to that of a Cessna or Beech.
Other examples:
In a small Cessna the rudder, as said, is simply connected to the pedals by steel wires. The nosewheel is connected to the pedals, too, so when you taxi a C172 for example there are two springs at the nosewheel that center the wheel and hence the pedals, as long as you move. To overcome the limited NWS angle and do tighter turns you need to use additional wheel brakes.
A Short Skyvan for example has steel rods instead of cables that actuate the control surfaces. It has twin rudders and they are really strong. On the ground there is absolutely no self-centering except the prop wash if the engines are running. For groune steering it has a tiller.
Other aircraft have rubber straps connecting rudder and ailerons to move them together, if you steer on the ground your yoke moves, too. If you held the yoke in position you‘d have a centering nose wheel ^^
This is where the following thread is most relevant.
Heh, yeah, I’ve already contributed about as much as I can there, haha. Seriously though, many folks have zero idea the difference between feet on the ground, tail in an office chair, and all the micro and macro accelerations you get during flight, especially in IMC. There’s a reason they say “178 seconds to live.”
Yes. Loss of concentration, whatever the cause, can soon be very bad news…
What I am trying to discover is:
I am looking for generalized guidance so I can try to build a set.
Can you recommend a particular example and/or online construction guide?
I’d like to hack something together that will be useful but not incredibly expensive.
(I would buy a set, but the Russian sanctions make that essentially impossible.)
Over and above the rudder input axis, you’ll need a braking axis for each pedal so that you can control the braking of the left and right wheels.
If you get fed up trying to make these things I can recommend the Thrustmaster TFRP rudder pedals. Everything you need, low price, lasted me a long time. If you’re willing to spend a little more I now have the Turtle Beach VelocityOne rudder pedals with Hall effect sensors. Slightly better in my opinion, more than double the price though.
That’s obviously the best option.
The problem is that I am stuck in Russia, and because of the political situation, things like this cost more than a decent computer, if they’re available at all.
So. . . . . 
