My homemade FFB controller

[Mizoo]

Hi, simracer fans

I just wanted to show you my last project.
After seeing the Steph Bord and V8Ben videos I wanted an FFB Happ steering wheel too !

But, instead of hacking a logitech board, I built my own FFB controller:

It's based on a Blueboard LPC1768H (I have also a version for LPCXPRESSO), 34$.

The main specs are:
- 1 kHz refresh rate output signal (ie: for AMC)
- 1 kHz refresh rate for USB data coming from game (even if most games actually update the data only 60-100 times per sec.)
- incremental rotary encoder for the steering wheel position (I'm using a 2048CPR, 8192 position per rotation, on direct drive)
- compatible with G25 pedals (and shifter soon)
- configuration via OLED display (soon)
- FFB monitoring, to avoid clipping (currently via serial port, and on OLED soon)
- no need to any driver

To drive the motor, I'm currently using an AMC servo drive, but I will build my own motor controller once the firmware is finished (for brushed and brushless motors).

I also removed the mechanical stop of the steering wheel, since it's managed with the motor (the steering angle is configurable).

This setup is more strong and fun than my G25 (I rediscover rFactor that I disliked before).
I can have strong FFB effects without clipping.

I think to provide a firmware soon (maybe for few bucks or donation).

 

[isamu]

Isamu, it's an Immersion card on the ECCI 7000. If you want electrical stops liKe the Fanatec or G25, you have just to connect your DC motor with a 30A8 or 12A6 AMC amplifier and the Blueboard card with the Mizzoo program and let's go

The Mizoo software with this combo allow us to control the motor on our wheel, and apply a mechanical "stop" to whatever degrees rotation we want...

thanks for the reply Stef. That's sounds rather complicated and since I don't want to void my warranty I'll pass on that suggestion for the time being lol

 

[Stef Bord]

It's under warranty, so I understand that... But the conversion is not difficult...

 

[Mizoo]

When I see the ECCI7000 price, I tell you, "don't touch it!"

 

[Mizoo]

Little soft with autoit to monitor the force:

As you can see, with these settings there is some clipping (clamping?).

 

[Sam Binfield]

As someone with some electronics knowledge (mostly valve amplifiers) and technical background I am very interested in this. I've looked into doing a FFB wheel before, but the programming required is simply beyond me, and so I take my hat off to you . Do you have any plans as to what you will do with the firmware? Be it for sale, by donation, or for free rolleyes? My DFGT is giving up the ghost, with overheating and other issues, and I'm looking to use something like this as a replacement, or maybe just cannibalise the board out of my DFGT.

Thanks for sharing this project with us,

Sam

 

[Mizoo]

Hi Sam,

for now, I just provided the firmware to few beta testers who can use it.

I don't think to sale this software, because it implies some constraints against "customers".
Donation is maybe the solution ...

 

[Sam Binfield]

Cheers Mizoo,

I've been reading the PID specification and I think I have a clearer idea of how the whole system works now, and unfortunately this has only confirmed that the necessary programming is beyond me. I've also read some of your thread over at racingFR, and I was wondering what kind of motors were preferred by those who have tested it so far? Brushed or brushless and what kind of torque rating? In addition, I am curious to know if there is anywhere where one can purchase an AMC servo driver at a reasonable price? If not I may have to look into building one myself .

Thanks again,

Sam

 

[Mizoo]

Sam,

after our measurements, we can say that the minimal torque to fully operate the steering wheel is 7 N.m, especially if you use a "real" wheel (> 30cm), and the minimal power is around 200W.
On my Happ, the motor has 1 N.m stall torque (and around 100W), the ratio reduction is 1:3, so 3N.m on the main shaft; with my 25cm wheel it's not sufficent.

The second main criteria is the cogging torque, the motor must be as smooth as possible !
As you can see on , it's not my case.

You can use brushless (with AC driving, with encoder) or brushed motor.
The latter is more affordable, cause it just need a "simple" DC driver (with current feedback) without sensor, an AMC for example can be found on eBay for 30-40 $US.
Don't forget the power supply (~40$US for 36-48V 300W).

A big AC servo motor can be used in direct drive, but a full combo (power supply + servo drive + servo motor) is really not cheap !
Stef Bord won such motor on eBay, it's a monster !

And we talk about a powerfull wheel, it has nothing to do with a logitech G25 (that I also own) !

 

[Stef Bord]

A little drive with Mizoo firmware,my Happ and the mod DRM...

 

[ProSimEU]

Hi Mizoo, really interested in this as we are trying to get our Frex wheels working and anything we can do to avoid either dealing with Frex or having to wait 12 weeks for delivery is music to my ears. Am more than willing to look at helping you out with some beta testing/butchering the Frex and welcome any recommendations for replacement motors as the Frex motors are impossible to source unless you buy 100s

 

[Paul Peraic]

Some people ask me questions about the rotary encoder, here some pix:

It's an optical rotary encoder (model accucoder) bought on eBay for 22$US.
Resolution: 8192 points per rotation (I also have a 20.000 PPR).
The precision is more than sufficient!

Could you give a model number to the optical rotary encoder ? Also would you know if this could replace the optical rotary encoder in the Logitech Driving force pro and will it actually work ?

 

[ernespeed]

Incredible work Mizoo!!!!!!!.

 

[Mizoo]

Paul: the board works with any rotary encoder with quadrature phase interface, I don't know for the logitech one.

Thanks ernespeed!

 

[mechamorafa]

Hi Mizoo, I've been following your project and I am very impressed.

I have a G25 and the right motor burned and gave a short on the board. I'm trying to fix it and then I'm gonna make a Mod in it. I had an idea of using the PMW signal from the board, amplified with fast and precise mosfet to drive a single stronger motor, direct driven, with a high resolution encoder on the shaft. Since you have a G25, do you think it is worth?

Another thing. You mentioned before about FFB controller from Immersion and Logitech. Is it possible to get a stand alone Logitech board if it is impossible to fix mine?

Thanks already.
Rafael

 

[isamu]

Hi Mizoo? What's the latest on the project ma nizzle?

 

[Mizoo]

@mechamorafa: you can adapt, via power interface, a stronger motor on a logitech board. But you cannot use a too high resolution encoder, a firmware limitation.
Broken Logitech wheels can be found on sim racing forums.

@isamu: I'm quite busy for several weeks, the "beta" stage is closed, I don't provide firmware until the final version.
And to avoid piracy (as a previous project), the board will be shipped by me.

 

[isamu]

thanks

 

[Paul Peraic]

Could you give a model number to the optical rotary encoder ? Also would you know if this could replace the optical rotary encoder in the Logitech Driving force pro and will it actually work ?

Thanks Mizoo

 

[Stef Bord]

My new combo, Micro DC 100 Motor with Redimount planetary Gearbox. Constant torque on the wheel 10Nm driven by Mizoo Board. It's awesome...A short video on Netkar Pro...

 

[Kasper Stoltze]

Looks awesome Stef!
Do you have any link for the motor, supply etc.?