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• Visualize your FFB

  Nikiss999 • 02/08/2021 at 22:25 • 0 comments

  If anyone ever wondered how would force feedback look on graphs here's a nice representation

  MMOS will be tested as well against OpenFFB. This one might get very interesting :)
  

• Smooth Boi

  Nikiss999 • 01/29/2021 at 23:08 • 0 comments

  Smooth Boi enters the game

  And with it the support for 3 phase BLDC, AC Servo permanent magnet, Hoverboard, RC Drones, Mige, whatever more name you can think of brushless motors.

  This is hoverboard motor btw

• Torque test !!!

  Nikiss999 • 12/08/2020 at 19:31 • 0 comments

  Well, all before this was just empty talk without any info on actual strength of the boi. Time for a reveal:

• Testing video

  Nikiss999 • 11/21/2020 at 01:04 • 0 comments

  This has been long overdue :)
  

  But finally it's here, testing and driving

• The 36V goodness

  Nikiss999 • 11/14/2020 at 21:23 • 0 comments

  Well the title says everything.

  Forcefeedback is really good now, compared to what it was before (don't think that it was bad before with 12 Volts power supply, now it's just very good). Everything is snappier and Stronger. Cogging is also reduced because of that new closed loop current control.

  Higher voltage gives more headroom for faster rotation. This means that you still get feedback even when counter steering the force from the game. With 12 V, at some point you hit a brick wall and you can't push enough juice into motor to keep FOC running.

  This also means that the wheelbase can murder you. Stronk boi is really really fast now and that boi can punch you really hard.

  Here are step log results, from wheelcheck

  Wheel mounted

   

  No wheel

  12V with wheel 

  (this chart is flawed, 1080 degrees were in mmos and 900 in wheelcheck, however there is no big change, line may get a little steeper but it won't come close to -5000)

  Stay tuned for some stronk boi video action!

• Another improvement, revamped current control and reduced noise

  Nikiss999 • 10/06/2020 at 23:39 • 0 comments

• Found out where the problem is

  Nikiss999 • 09/23/2020 at 11:29 • 0 comments

  Usable force should be about 5 Nm in this moment. Electronics start having a mental breakdown above that level.
  This is the reason why wheel started feeling bad at higher forces. Current control is actually very good until 5 Nm. After that there are huge deviations, we are talking about 20 - 40 % difference in expected output vs reality.
  Notchiness is still there. I won't even try removing it until full 12.5 Nm are extracted from the wheelbase. Strength is the priority

  Edit : The noise in the previous demonstration videos is because of the bad current control. Motor starts squeaking above 5 Nm. If filmed at 5 Nm that there would be no squeaking noise.

• Another improvement and torque measurement

  Nikiss999 • 09/19/2020 at 21:59 • 0 comments

  Did some Nm testing. At 25% strength wheel was able to lift a 2 liter bottle at 12 cm from center of the shaft. That is about 2.4 Nm. Don't have concrete results yet but that should be about 10 Nm at full strength. For now.

  Turns out that bts7960 is not up to the task for closed loop current control. I made another diy bridge and current control now is much better. Current control is still not perfect. But good news is that torque unevenness is much Much better now. Didn't have a lot of time to calibrate it properly. This also solved the problem with fast rotation. Now the strength when steering quickly is not reduced. In fact if I didn't know that the problem existed I'd never notice it.

  Notchiness is still there. However below 50% strength or 5 Nm you can only feel the "tip" as a notch. Everything between steps is butter smooth.

  Driving with now improved wheel was a blast. Everything below 5 Nm is a meme. It is just not strong enough. 5Nm to 7.5 Nm is good. 7.5 Nm to 10 Nm is really strong. At 7.5 you feel road texture and it is the sweet-spot. More than that and you start struggling to make corrections. But it's too much fun to drive at 10 Nm.

  In summary:
  - Notchiness got lowered by let's say 70%
  - Speedy corrections and rally driving is not reducing strength anymore
  - 7.5 Nm is the sweetspot

  Flux weakening will be one of the next research steps. It reduces torque and increases power consumption but greatly increases rotational speed. However I'm still not sure if it affects notchiness between steps. If it breaks FOC which is used right now then there's no other solution but to use power supply with more than 12 Volts.

• Second wave of driving videos - actually usefull this time

  Nikiss999 • 09/14/2020 at 11:37 • 0 comments

  Some usefull demonstrative driving videos, unlike previous ones.
  

  This one is in assetto corsa and it really shows how strong the wheel is. 

  This one is from dirt rally and it was an overall good representation. At the beginning I intentionally removed one hand from the wheel and you can see that the thing is kicking around a lot.

• Videos and benchmarks

  Nikiss999 • 09/13/2020 at 20:11 • 0 comments

  Did some iracing wheelcheck benchmarks and software for the driver was optimized as well.

  Here are links to the videos:

  Benchmarks:

  Driving:

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