DIY FFB Steering wheel (MMosFFB ) (In Progress)

Hmm, that's tempting. Is there any reason for only running the 12V power supply though with a 48V motor? I realize that voltage is more about speed than torque, but they aren't exactly completely discrete from each other.

Also, from looking at those motor drivers, do you just run them in parallel for increased current capability?

The motor is rated at 1000W, but that is when it is moving. Since we are stalling the motor, all that energy has to be lost as heat rather than rotational energy. The motor is designed to withstand a certain loss to thermal energy but not 100%. Therefore you run the motor at what would be normal for heat related loss and have (almost) no rotational energy.

Ah, very interesting. I'm assuming you could run it harder with some better cooling like a clamp on heatsink and fan, though I guess the problem is getting the heat from the windings out to the case to start with.

To an extent, yes you can use a fan to help with it but it's only going to make so much difference before the enamel bakes of the windings and creates a short, it's all downhill from there.

Mine is mounted with a fan that pulls air into the motor. After a race, it's warm to touch on slightly light FFB settings.

Something isn't adding up to me. That motor only appears to be rated to 3 Nm or so (power numbers are all over the place, but from unitemotor.com at least they only go up to 750W, which has the 3 Nm torque rating: http://www.unitemotor.com/index.php/Home/Index/product_detail/id/172/page/1. Granted they also list 4 voltage ratings, but only 3 different power/torque ratings, so who knows. Are you running direct drive or belt/gear? My T300 theoretically has that much available already, so aside from being direct drive I'm not sure it would quite be what I'm looking for.

I'm not necessarily going for a "break your wrist" kind of force as much as I'd just like to get to a full size steering wheel with good feedback. The game controllers are all more like kart sized wheels, which "artificially" increases the force, but at the cost of my hands not quite feeling like they are in the right spot.

Hello friends!
Again turning to you for help.
I already have everything configured, I have tested the steering wheel and it works fine ... but the problem is that the bts7960 driver burns easily.
What can i do to fix it?

What do you think of this controller? Someone has tried?

https://articulo.mercadolibre.com.a...DlNMZ83xjMAUUBY5UejZ5kYNVZ05L7KxoChTAQAvD_BwE

Hi Petrollhead49, Zip racer here,
I am very much interested in your project of using an actual eps from a car. I have exactly the same eps model as you. I counted the gear ratio of a g29 motor pinion to main gear and it is exactly the same turns as the EPS motor shaft to steering wheel shaft..a happy coincidence. I got a surplus G29 with a working board but dead motor. I relocated the hall sensor based counter and its magnet from the G29 motor to the back of the EPS motor...more of a mechanical challenge than electronics as i did not change any of the circuits...just relocated the sensor. Note the polarity of the magnet and the distance between the magnet and the IC top when relocating. Doable with patience and imagination and 5 minute epoxy. To drive the EPS motor, I used the motor output of the g29 board to drive the input of two back to back optocouplers...and since the g29 no longer drives the original 2 motors, I now feed it with 12 volts instead of 24. And to avoid the optos leds being fried by too much current , a 10K resistor is placed in series (calculations actually put it at just over 1K ohm but I am being very careful at the moment so 10 k is a bit of an overkill maybe). The output of the opto is fed a 5volt dc from a dc down converter board tapped to the 12 volt supply. This 5 volt also feeds the IBT2 control circuit. The 12 volt supply drives the IBT2 and the eps motor which is also 12 volts (cars use 12 volts, right?). Now the EPS motor is rated at 80 amps as it needs to move the front wheels of over a ton of a car...but a steel full-frame mover sim is nowhere near the weight of even two car wheels, so I figured the IBT2 will have enough amp rating at 40 amps. I figured, at 12 volts and pulling 10 amps, the eps motor will output 120 watts which should be ample but not powerful enough to rip your wrist or arm off. The other challenge is how to mechanically stop the motor as it self calibrates..remember the G29 self calibrates by turning fast to the left, stop after 1 1/2 or so turns as it hit the mechanical stop, reverses direction until it hits the opposite stop, calculates, then centers. Now, how do we make the EPS motor do that? What I did is attach an all thread shaft to the opposite end of the main eps drive shaft (opposite side to where you mount the steering wheel), a bolt is placed in the all thread which moves up or down as the steering wheel is rotated right or left. This bolt will hit a stop after completing 1 1/2 turns to either side and when it hits the stop , it will open a switch which connects a big resistor in series with the EPS motor circuit. This causes the EPS motor to weaken considerably (less current coming in due to the big resistor in series at that point) and stop at the switch without breaking anything (EPS motors are really strong). As the motor stalls, the sensor attached to the motor shaft end stops sending impulses to the G29 main board, which interprets it as the original mechanical stop. The board then sends the reverse motor signal which causes the motor to reverse full speed as the switch closes and takes out the series resistor.

I used the motomonster board the first time around and found it very difficult to control. So after more readings, I came to the conclusion that the IBT2 board is simpler to use and more powerful. What I did is connect Len and Ren to +5 volts, and the Opto outputs to LPWM and RPWM pins of the IBT2 board. I am rewiring the setup at the moment so am not able to test yet.

To summarize, I am using the main g29 board as/is to drive the EPS motor thru the IBT2 board. The EPS that you and I use have the same gear ratio as the g29 motor pinion to main gear ratio! verify by counting actual motor shaft rotations to steering wheel rotation of the EPS..and G29 motor shaft rotation to steering wheel rotation. they should be the same.

P.s. I also used a cpu heat sink as described in this series...but mounted the copper side of the board to the copper side of the heatsink...used a silicon heatsink rubber tape to insulate the baord from the heatsink and prevent shorting. Good idea. Plus side to this is the cpu heat sink fan uses 12 volts supply also.

I am looking forward to testing once rewiring is completed.

I am using a switching 240 watt 12 volts PSU. Hope it will give enough juice for the EPS motor? If not, I will parallel a lead acid battery.

The only downside I can think of at this time is weight. The EPS alone tips at almost 8 kilos without the steering wheel.

It burns likely because it is shorting at the bottom (copper foil side of the circuit board) of the board and the uninsulated heatsink. Try separating the board from the puny heat sink by removing the 2 bolts. See how precarious the insulation is between the board and the heat sink (the chinese designers know this will fail but could not care less as shorted boards mean more orders and cash). As these 2 surfaces heat up, the likelihood of shorting increases. Solution? Try using a silicon tape like heat conducting insulator between the back of the board and the heat sink and tighten the board to the heat sink in their previous arrangement. Unless you repeatedly subject the IBT2 to heavy overloads, it should survive given its 40 amp capacity...unless you run everything at max...max voltage , max amps continuosly ...then it will surely die, pronto.

looking at your set-up I can see you are using the IBT2 as it came from china...like a ticking time bomb ready to short at the bottom anytime...if you look at the motor output trace at the bottom of the board, you will see that both traces are connected at the bottom copper traces directly under the main driver ics on the top side. both copper traces are insulated by the green colored resin from shorting with the heat sink...that thin layer of resin is all you have protecting the IC outputs to the motor from shorting via the heatsink surface as these two surfaces heat up during operations...pls confirm by checking the bottom copper traces of all your burned IBT2s to validate or debunk this theory.

I really like the quality of your build. Very nice looking. You did excellent machining. Hope you are able to solve the shorting issues.

The do not burn due to the this short. Just stop working. And when the short is removed, work as usual.

Thanks. Glad to know. Could be the built in protection circuits of the chip triggering. It comes back on once a fault condition such as over current or high temps is reduced or resolved. Good luck. Cheers.

I just started my own wheel project and first game was Pcars2 and i was thinking my settings are wrong, but after little investigation i saw what you ask. Have you got any answer?

Take any wheel profile in a game, and remap the controls with you wheel inputs etc.

Bro it's 2021 nw, does this have improvements, my g27 wheel died, currently using Thanos board to power pedals and shifter. Can my wheel still be brought to life

can you do board level troubleshooting of electronic circuits? or do you know of any friend who is good at troubleshooting electronic circuit boards?

No sir I wish I had., I can copy and paste with the eyes, if u know what I mean.

Anyway, can you kindly describe what happened or how it happened? did the g27 emit smoke, the steering wheel just stopped responding/turning or responding to game inputs? Are the led lights totally dead? Did the power supply or power adoptor get warm or hot? Possible causes are many...motors shorting inside or motor brushes getting plugged or shorted by excess carbon, or carbon getting totally eroded and failing contact with motor brushes. Shorted power mosfet on the board. Loose power supply connection. Bad adoptor. Bad adoptor wiring. Bad power adoptor power plug. Note that wires could break inside with repeated flexing or from being pulled or twisted over time as you use the wheel during games. How old is the unit? From experience, the G27 circuit board inside the unit is pretty good for its price. Got my first unit surplus and is working ok for years now. What would kill the board is a short coming from plugged motor brushes due to high carbon build up. That would happen depending on how long and how much time you have used the unit..but that would be a long time. Hope I can help you more...Cheers.

Hi Lesley, Got you. How long have you been using the g27? Did you have anyone to help set it up for you? Maybe you can request him/her to check all wiring connections..it could be an issue with power or cabling...hopefully. There is a 50-50 chance your g27 is alive...Cheers! Stay safe and healthy and enjoy the our e-sport.

zipracer