Suggestions on building a set of sim racing pedals?

[DiogoBrand]

Hello guys, I live in Brazil and I'm an avid simracer. Since every sim racing equipment costs 4 times here as it does elsewhere (our currency is worth half as much as it used to, and you pay double on everything because of import taxes), I have decided to try to design and build my own set of pedals, to upgrade from the current G27 set I currently own.

So far I have taken inspiration from two existing products:

From the Heusinkveld pedals, I took the idea of using load cells on all three pedals, on the brake pedal to measure pedal force, and for the clutch and accelerator, to indirectly measure travel by using a constant rate spring. Another good idea from this set is the way the clutch spring is mounted to give it a realistic digressive feel.




From this set of Wilwood 340 12410 pedals I took the inspiration for the actual pedal designs, for three reasons: They look good, they seem relatively easy to build and I've got access to cad designs from them.

I haven't got access to advanced building resources, like laser cutting and such, I'd mostly be relying on a drill bench, an angle grinder and a welding machine. For the electronics, I would be using load cells, two or three Hx711 boards and an Arduino pro micro board. This part I've already got mostly figured out since I'm working on a load cell mod for my G27 pedals at the moment.

What I'm actually looking for is: What tips can you guys give me that would help me build those? I'd want them to be sturdy, reliable, and with no play in the mechanism, which I believe would be a big challenge given the resources I have access to. I don't know if and when I will build those, but if I do and you guys have any interest, I'll be certain to share my progress.

[Jolle]

I think, if you keep it simple, a pedal is nothing more than a pivot. If you weld a sturdy base and weld some SKF bearings on there, you’re mostly done. You could even use some of the electronics of the G27.

Just make the base heavy.

[DiogoBrand]

I have thought about using the potentiometers from the G27, but they're a bit unreliable, since I have to disassemble and clean them every now and then as they start randomly spiking, so I think load cells would be more reliable.

This is a sketch I've drawn, it still lacks the base to hold everything together, but if I'm able to build them like this, I think it would provide a satisfactory result, and of course any tips will be welcome:

[Jolle]

maybe a very strange idea... couldn't you put a load cell inside a brake calliper? Maybe use a rear master brake cylinder from a motorbike, to get this real feel, and not a spring you're pressing against.

[DiogoBrand]

It can be done, there are plenty of pedals out there where the load cell is actuated by a slave cylinder, and I think it was yesterday when I saw a project where a load cell was actuated by a brake caliper, but at that point it's a matter of diminishing returns, in my opinion. You're adding a lot of cost and complexity for a relatively small change in feel, so it's not worth it for me.

[coaster]

Squashing a tennis ball on a fulcrum of maybe 3.5 to 1 would give a good pedal feel, force feedback would from gyroscopic precession would feel realistic but would be difficult to build, a 10 inch disc grinder with 4mm steel disc fix the grinder to the column and turn the game noise up with 2 large guitar amps to drown out the sound of the grinder.
Maybe hook up a real motor to the gas pedal without a muffler and point directly at the neighours windows?

You asked,

[stez90]

What electronic base are you going for? I would suggest analog amplifier for load cell, like INA125P or similar . If you keep a 0-5V analog signal you can wire it in place of a potentiomenter in an existing board or to an ADC port in a custom one. Also HX711 is slow in refresh rate, as far as I remember.
For pots, go for Hall effect ones, no friction, no noise, reliable... And you can make them by yourself.

[graham.reeds]

Squashing a tennis ball on a fulcrum of maybe 3.5 to 1 would give a good pedal feel,

Back in the early days of force feedback a popular mod was using a squash ball.