[WIP] DIY Rudder pedals - design input wanted

Hey guys,

After getting to use some rudder pedals I decided my simming really needed some proper ones, and spending 100€ on a set of plastic ones didn't really seem like money well spent. I tried my friends Thrustmaster pedals and they really lacked the feeling and tactile response I was looking for, so I scoured the net for DIY and professional level projects to get inspiration.

I got an educational version of Inventor Pro 2018 and started tinkering, mind you I am NOT an engineer nor do I have any product design experience. I do not have access to fancy machining equipment either, but I am in the middle of a house renovation (the stressful part is over, thank god) so I have a lot of wood working equipment.

The BF109 style pedals seemed like a good place to start. Since I do not have metal machining experience or equipment I needed to use sturdy enough parts of massive wood and I really didn't fancy doing it all out of plywood because I don't like how that looks. I have some 28x28mm left over from a kitchen shelf project and it seems sturdy enough to work as the arms. I plan on having 8x22mm ball bearings on most of the pivot points, I think 8mm bolts will be sturdy enough as axles. For centering I thought the cam with follower seemed like a good idea - the bad news is I have no idea how to properly design said cam. The fairly massive one you see in the renderings are just me SWAGin it. But basically centering is by a spring loaded arm and a ball bearing follower moving against the cam. The spring is missing from the pics because I couldnt figure out how to make a spring yet in Inventor :doh:

The pedals will have some small gas shocks on them.

Electronics wise I will start out with a discarded logitech 3d pro - it has three axis I can use - but will go down the leo bodnar route eventually. Still haven't decided if I want to just go leo bodnar straight away, hall sensors would be easier to mount I guess. The sensors and mountings are still missing from the drawing, since I haven't quite decided what I want to do yet. I also have trouble conceptualizing how to best mount pot sensors.

I am also considering a cheap motorcycle steering damper to add additional tactile feel, like this one for example:

http://www.ebay.com/itm/Universal-Motorcycle-Steering-Damper-Stabilizer-Linear-Reversed-Safety-Control-/282615215834

So, any input is appreciated, I figure if I do the design work properly first building it will be a lot faster and easier on the nerves :megalol:

Still haven't decided if I want to just go leo bodnar straight away, hall sensors would be easier to mount I guess.

You don't need Bodnar controller for use HALL sensor, the Logitech circuit could be used, for controller HALL sensor is like a potentiometer.

For use HALL sensor is important that rudder main pivoting points use ball bearings, as the sensor can detect the minimal undesired lateral movement of rudder bar, disturbing the axis response.

Notice that the "CAM" profile could not be symmetric, due the change in angle of the spring lever.

This circle in the middle of CAM will create a expressive "bump" in center position.

IMO - Bodnar controller is overkill for make a rudder pedals, today could be used the more affordable Arduinos.

Thanks for the input!

I guess I'll have to score some Hall sensors then and see.. I read alot about the Arduinos but the Leo Bodnar seems more plug and play.

Regarding the cam profile, I read that earlier about not being symmetrical but I have no idea how to design it properly, I guess I will have to go a bit by trial and error. I am away at work so I have a good week or so to perfect the design before I go building it.

I tweaked the design now, the cam profile is no longer symmetrical and is closer now to what it should be, the arm moves more or less equally on both sides. I ordered the steering damper and the gas shocks on ebay, shipping time was not fast but I got time :)

Now I need to integrate the steering damper

Why do you want some form of centring cam??

Just use damper(s) for your left/right rudder.

Not surprising about the controller although I am not sure about Leo Bodnar or maybe do some HID programming on an Arduino.

My mods of a 3D pro so far :D

I'm also developing a toque pedal design as well as a better cyclic.;)

I got the idea from other devices, many more professional level products seem to use them to get a crisp centering feel, so you know when you are centered which is more important in fixed wing flying. If you want to get rid of the centering you just unhook the spring.

With the steering damper you still get a feel for of feedback. I hope it just aint too stiff / sluggish.

here is a pic of the first integration of the steering damper, and also a picture of my previous project, which was a very ad hoc helo sim controller made out of a discarded logitech 3d pro also + some other bits and bobs i found lying around. It worked reasonably but really was without any kind of feeling which was off putting, also the mechanical parts had too much play. So now I am trying to get a nice smooth operation this time around, I will probably at some point make a stick and collective too, perhaps a throttle to create a nice dual use home cockpit (fixed/rotary wing)

Your project looks cool, some good ideas for when I get around to doing a new collective stick.

Why you don't make the foot rest in "combat" style pedals, with heels on floor?

http://i.imgur.com/fGqQgSR.jpg

I suspect this wood structure pivots will result a bit flimsy with foots over with this "Bf 109" style foot rest.

BTW - If you reduced the size of "parallelogram" achieve more turn over sensor:

http://simhq.com/forum/ubbthreads.php/topics/3990867/re-slaw-vs-milan-the-battle-of-the-pedals#Post3990867

Pedals without a kind of center system only if you plan use exclusive for helicopters.

Thanks Sokol, those are some good ideas and good links. I will think about reducing my paralellogram, but I have faith that massive wood will be good enough. If not, redesign is not a problem really.

Also nice bonus about the MLX90363 sensor - seems like a real winner. I will order both the MLX 3d hall as well as a set of normal A1302 hall sensors, and arduino UNO r3 and a 16 Bit I2C ADS1115 Module ADC 4 channel with Pro Gain Amplifier for Arduino RPi. Decided to go the Arduino path since it seems to be the least expensive way. I sure have ordered a shitload of stuff now :D Need to study the Arduino now - how to make it work.

EDIT: to clarify I made some measurments in Inventor, my rudder pedals have a travel range of 35 degrees, that equals a distance/travel of about 23cm at full deflection (from pedal lower edge to edge). The rotor arms are from pedal unit pivot to pivot 44cm, wider than most commercial pedals but not excessive - or is it? A shorter rotor would certainly place less risk of bending and breaking of the rotor arm...

Another day, another design - Sokols sage advice had me seriously consider heels on ground pedals and started sketching on a design. Not pretty, especially the long 8mm threaded rods I'd use to offset the pedal from the mechanism.. Hmm

Another day, another design - Sokols sage advice had me seriously consider heels on ground pedals and started sketching on a design. Not pretty, especially the long 8mm threaded rods I'd use to offset the pedal from the mechanism.. Hmm

Hi,

Building the pedals of wood is ok in my opininon, but I would oversize the bearings. The problem with wood that it doesn`t take much surface pressure without local deformation. The small bearings deliver a high surface load onto the wood which will wear out quickly and your bearings will go loose.

So you need to minimize surface pressure by increasing the contact area. Use large OD and wide bearings in a hardwood base. Sokol`s idea is great to rest your heels on the floor instead on the pedals, so the vertical load on the mechanism will be lower.

Making a CAM mechanism of wood has the same challange. The CAM roller has a tiny contact area with the CAM plate. Combine it with a high springload and you will have a very high surface pressure on the CAM plate. The roller will wear out the wood pretty quickly.

Good luck!

Thats a really good point. Especially the cam will be suspectible to wear. I guess I could put some sheet metal over the cam surface to reduce wear. As for bearings, yeah oversizing might work or I could make inlays for the bearings made out of composite material, like a cutting board or some such.

Ok, here is the steering damper integration, plenty of space in the middle. I will probably achieve about 40 degrees of angle vs. 35 for the old layout.

Don't rule out using actual ball bearing assemblies, I have now used them in my collective with good effect replacing the bushes that I used in an earlier build.

Yeah that was my plan to use ball bearings, the big holes are cutouts for the 22mm ball bearings. I plan on having ball bearings in all moving pivots except the gas springs and damper.

Can someone show me how you have your magnets and hall sensors set up? How far do the magnets and sensor be from magnetic metals (steel)?

Probable the best option is use diametrical magnetized rings and place the sensor inside the ring.

Or the "Bic HALL pot" assembly, with two square magnets.

http://simhq.com/forum/ubbthreads.php/topics/3674791/DIY_Sealed_Minature_Hall_Pots_.html#Post3674791

http://www.mikesflightdeck.com/images/hslin.jpg

I found some neodymium magnet rings with 16mm diameter, so if I place these outside of a 16mm plastic tube and the sensor inside the tube I will be good? Or is 16mm too much?

Only trying to know, generally the more close the magnet to sensor better, the ideal distance is ~2/2.5mm.

BTW - In this video the guy are replacing the main bearings in their T-Rudder "clone" - he is aeronautical mechanic and has access to some advance machine tool, so can easily work with metal.

The reason for replace the two bearings in the magnet support axis by conical bearings is because the previous bearing model allow small lateral movement in magnet support axis, what disturb the HALL readings (I have the same problem installing HALL in CH pedals, that don't use bearing in axis pivot and so had lot of lateral play, no issue for pot, but problematic for HALL.

Notice that in T-Rudder the axis for magnet support is not direct in pedal bar, but indirect moved using turnbuckles for transmite the pedals movement for magnet support axis.

In a pedal where the magnet is installed in main bar axis the risk of this (possible) issue increase, since foots weight are acting over the bar.

Yeah ok, good to know. I thought a lot about sensor placement in the brakes today, and thought about getting a spur gear setup that transfers the main pivot point in a 2 to 1 ratio to a second bearing with a bic pen hall pot inside. This way I get a larger usable movement. 3d printing said gears would be easy but I don't have access to a 3d printer right now.

IMO - You should avoid use gears - unnecessary complication, and brake pedals don't need much course.

I see that you take it very seriously so my advise would be to drop the wood and do it in aluminium.

Aluminium is not so expensive and you can buy all pieces on ebay. Also toolwise you need pretty much the same tools as for wood.

For inspiration, see below:

https://forums.eagle.ru/showthread.php?t=181647

https://forums.eagle.ru/showthread.php?t=171406

You know Huzar I initially resented your for your comment, but the more I thought about it the more I realized you were right - it will simply look clunky made out of wood and will probably lack the precision I need. So after some googling I found something that I knew existed but had no idea was so versatile - waterjet cutting. And, luckily, a local machine shop has a 3-axis cutter, so I went there today and asked, prices were pretty fair though I have not gotten an exact quote yet (starting cost 40€ + 1,8ish € per minute of cutting + the time it takes to insert my drawings into the machine). Cutting aluminium is pretty fast, even though twice as expensive as steel it will probably be my solution. The drawing shows 12mm material thickness but I will probably go with less, something like 10mm? Thick material does have it's advantages, I need to do some drilling to fasten the gas damper and the pedal ball bearing ears, so less is not always more.

Anyways, here is my revised drawing. Looking forward for comments.

Hello I saw your project. It looks nice. I would advise if you are using wood then use bearing on all joints other-wise it would not be precise. You have saw my DIY project, the link of my project is in my signature. I have used 4 bearing for each pedal and 4 bearing for center joints. I have also updated my mechanical for actual rudder axis. Due to bearings my pedals are perfectly precise, butter smooth and I am a chopper driver :)

Hi, yes I saw your pedals, good job and kudos for an excellent writeup on your method and parts used. I was going to use wood, but now that the possibility of having expertly machined parts are almost within reach is seems kinda cool to do that. Regardless, I will use bearings on all axis.

I am struggling right now with my cam and follower design, unsure how to make it work best.

Aand last picture before the weekend, the cam profile looks pretty nuts but it gives the same rotation value for the follower arm on both sides = equal spring force on both sides??

I have not yet seen a well designed, precise and good looking wooden pedals plus wood will wear and loose integrity rather quickly. It just not worth it when you spend so much time on designing, building, materials, tools etc. And my free time is the most valuable item in this equation.

How did you design your cam profile? It was one thing I straggled with and at the end I opted for simpler centering mechanism. And I'm afraid your design for pedal brakes won't work very well, the upper rod will just twist under the load. I think the gas strut should be mounted directly to the pedal and then somehow fixed to the arm.