Linkage-less aircraft rudder pedals

[Dragon1-1]

I'm looking for rudder pedals that would be akin to this: 

Ignore the caption. Single, solid bar, with no linkages of any kind. High forces on both toe brakes and the rudder axis. Are there any commercial or DIY projects going on that would go in that direction? Last I heard, RealSimulator was the only one trying, but I don't see those pedals being sold.

Pendular rudder with realistic force (about 100lbs at full deflection) and throw would be OK, too, if anyone knows of a project doing that. Most designs I've seen look far too flimsy to take that kind of springs.

[Ala12Rv-Tundra]

Slaw RX or Simple SImpit pedals come to my mind, but not many other units

https://slawdevice.com/en/glowna/3-rx-viper-v2-rudder-pedals-dark-metallic.html

 

https://www.facebook.com/commerce/products/the-rudder/3866697563448683/?ref=page_home_tab&referral_code=page_shop_card

[hsth]

Slaw has a new device PRE-ORDER!!! RH ROTOR Rudder Pedals - Slaw Device 

[Dragon1-1]

1 hour ago, hsth said:

Slaw has a new device PRE-ORDER!!! RH ROTOR Rudder Pedals - Slaw Device 

This is an inverted pendular rudder, like you'd find in a helo. Not exactly a configuration I'm interested in. Might have the right forces, at least (since it's metal), but it doesn't say anything about it on the product page.

13 hours ago, Ala12Rv-Tundra said:

Slaw RX or Simple SImpit pedals come to my mind, but not many other units

These use a pantograph linkage. Not what I'm looking for, I already have a DIY set using that mechanism. I you look at the Viper pedals pic I posted, the two toe brakes are on a single piece of metal. They don't stay parallel to your feet. That's how the actual rudder works in both Viper and Hornet, and in many other aircraft, too (particularly those without toe brakes).

[Hempstead]

Something like this? 100% home made. But please note that this project has gone through 5 complete redesign, over the past 13 years. Even I myself couldn't wait for it and bought TM's TPR b/c I wanted to fly F16 and F18, and AH64 now, not next year. However, I am rather sure there will be no major redesign, as the main mechanism is working very well -- I have completely resolved the torque binding of the linear ball bearing problem that had been plaguing me for the last 10 years, once and for all.

What's missing are:

1. The new Hempstick Pico to be able to drive the industrial servo motor and serve as an USB controller.

2. Force sensing toe brakes. Some partial prototypes in progress.

3. prototype the new pivot-bar-less modification.

The picture is a bit old... the new modification has no central pivot bar... one less thing to make with milling machine. That reduced the parts requiring milling machine to a big fat zero (although a CNC milling machine would be nice to have in the manufacturing process).

The designed force for the main axis is about 40 lbf, toe brake, 20 lbf.

 

And NO FFB! Don't ask. I refuse to support FFB. It's possible to get it to work if you get rid of the motor and no toe brake, and put in spring centering, and other controllers, like the original Hempstick, or whatever other controllers. Obviously, I am not into that. It's a nice to have feature if I could cramp it in, but will be ditched in a heart bit if my main design conflict with it.

 

[Dragon1-1]

That looks nice, but it's another design with linear motion. That's not how the real pedals move. They don't slide, they rotate around a central pivot. With pedals deflected, the toe brakes are not parallel to the foot. Weird, but that's how it is in both Viper and Hornet. The rails you see on the picture in the OP are only for moving the entire unit back and forth to adjust the pedals.

I'm interested in pedals that work like in the real aircraft. The mechanism is actually real simple, it just needs to be strong enough to withstand the forces involved, and I'm not enough of an engineer to do it.

[Sokol1_br]

On 3/25/2022 at 10:27 PM, Dragon1-1 said:

 They don't slide, they rotate around a central pivot. With pedals deflected, the toe brakes are not parallel to the foot.

The detail is that this pedal has very short movement, It's said 19mm for F-16, working more as pressure transducer.

 

[Dragon1-1]

That's interesting. Would this design work if the rails were removed and the central linkage replaced with a solid bar on which the toe brakes could be mounted? Mechanical stops would have to be added, of course. If the main bearing could take that sort of force, then maybe it could be made into a design that I want.

[Ernest]

On 3/28/2022 at 4:19 PM, Dragon1-1 said:

That's interesting. Would this design work if the rails were removed and the central linkage replaced with a solid bar on which the toe brakes could be mounted? Mechanical stops would have to be added, of course. If the main bearing could take that sort of force, then maybe it could be made into a design that I want.

the reason the f18 pedals and f16 pedals are like that because they have very short travel so the pedals not being parallel to the foot is not much of an issue. If you make a set of rudder pedals with linear motion and give it the same travel and force as the f18/f16 pedals and compare them then you wont feel any difference. Pedals like this should be useful for anyone flying fixed wing but useless for rotor. But If you make it force feedback pedals then you could simulate any pedals you want. I have two designs in mind that can achieve 100lb+ and one is already proven. 

[Dragon1-1]

I doubt I wouldn't feel any difference, human senses are quite sensitive to angles, even 19mm of travel would be enough to feel rotation versus sliding. Besides, a single bar mechanism is actually simpler and more robust than sliders are. 

Force feedback is great for warbirds and for older jets, which had long pedal travel. For F-16 and F-18, though, I would prefer to have a realistic mechanism, complete with a force transducer (although since they do move, a geared Hall sensor could do just as fine).

[Ernest]

If you put a displacement style sensor on it then it would work just like regular pedals. You would need to tune its curve to be proportional to the force you are pressing with otherwise you could be pushing 300lb from 100lb on the pedals and the game would could see 5% increment only, while you could be pushing 1lb more but the game detects 50% change. 

Forcefeedback is not only great for war bird or older jets but also for helicopters and force based pedals. How? Well simply they can be set up with different travel, max force, force curve, damping, friction etc. In other words if you want in software  you can give them 2 inches of travel with 80lb of max force and a exponential force curve to mimic the exact feel of f18 pedals and also set your axis output to force instead of displacement. Then lets say you want to fly a helicopter,  so instead select a helicopter profile which mimics helicopter pedals and so on. 

 

In actual use even if you could detect rotation vs non rotation it wont make any difference, all that matters is the force with which you are pushing on the pedals. 

Even still I would like a cheap single bar design with loadcell for jets which use force sensing. I think it makes sense if it can be done cheaply which I belive it could. 

Edited July 13, 2024 by Ernest

[Dragon1-1]

The problem with Force Feedback is that I haven't seen any system strong enough to truly emulate a hard stop. A mechanical stop has a distinct feel and it can't just be pushed through. To emulate that, the motor would have to be able to resist an enormous force. 

Of course, there's also the possibility of a bolt-on physical stop that you can attach and detach according to what you're flying, like with detents on the Winwing throttle. However, the motors would need to be aware of the stop, to avoid damage.