Sim Racing servo ffb systems : OSW & Bodnar

Discussion in 'General Discussion' started by Adrianstealth, Jun 1, 2015.

  1. Euskotracks

    Euskotracks Registered

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    In principle it should be the most restrictive of both. Considering USB restrictions I would expect that rF2 is using the same bitfield for internal calculations.

    However
    16 bit = 65536.
    1080/65536 = 0,0165 deg
    360 deg / 0.0165 = 21845

    That is 4,37 times the precision of a 5000 PPR encoder.



    Enviado desde mi GT-I9505 mediante Tapatalk
     
  2. DrR1pper

    DrR1pper Registered

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    Doesn't 16 bit give us up to 65,536 discrete data points? Spread over 1080 degrees, wouldn't that give 21,845 PPR?

    edit: nvm, Eusko beat me to it.
     
  3. Joe

    Joe Registered

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    OK, interesting. I looked the ISI plugin code and ran, I got the telemetry output frame is 10ms. As said in the comment of codes:

    void ExampleInternalsPlugin::UpdateTelemetry( const TelemInfoV01 &info )
    {
    // Use the incoming data, for now I'll just write some of it to a file to a) make sure it
    // is working, and b) explain the coordinate system a little bit (see header for more info)
    FILE *fo = fopen( "ExampleInternalsTelemetryOutput.txt", "a" );
    if( fo != NULL )
    {
    // Delta time is variable, as we send out the info once per frame
    fprintf( fo, "DT=%.4f ET=%.4f\n", info.mDeltaTime, info.mElapsedTime );
    fprintf( fo, "Lap=%d StartET=%.3f\n", info.mLapNumber, info.mLapStartET );
    fprintf( fo, "Vehicle=%s\n", info.mVehicleName );
    fprintf( fo, "Track=%s\n", info.mTrackName );
    fprintf( fo, "Pos=(%.3f,%.3f,%.3f)\n", info.mPos.x, info.mPos.y, info.mPos.z );

    On the forceFeedback function they did not comment on the code:

    virtual bool ForceFeedback( double &forceValue ) { return( false ); } // alternate force feedback computation - return true if editing the value

    I may need to output the ForceFeedback data to see....what is "frame" window is.

    Question: the USB HID report rate would be 400Hz?
     
    Last edited by a moderator: Dec 7, 2015
  4. Marek Lesniak

    Marek Lesniak Car Team Staff Member

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    Those encoders are of quadrature type, as I mentioned before. 5000PPR gives effective 20000 impulses per 1 rotation.

    EDIT: Yes, typo :) Now it's OK
     
    Last edited by a moderator: Dec 7, 2015
  5. Beano

    Beano Registered

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    @ LesiU: 5k PPR encoder will give 20k counts per 1 rotation.

    Thought you just made a typo there...

    Cheers,
    Beano
     
  6. Euskotracks

    Euskotracks Registered

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    OK I thought PPR meant effective pulses per revolution.

    Enviado desde mi GT-I9505 mediante Tapatalk
     
  7. DrR1pper

    DrR1pper Registered

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    Ah ok. My mistake.
     
  8. Beano

    Beano Registered

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    I think it goes such that in quadrature encoder, PPR (Pulses per Revolution) = 4x that in CPR (Counts per Revolution) - but anyway, it is always advertised as PPR and effective counts is 4x the PPR.
     
  9. Marek Lesniak

    Marek Lesniak Car Team Staff Member

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    EDIT: nvm, Beano was faster :)
     
  10. Spinelli

    Spinelli Banned

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  11. smbrm

    smbrm Registered

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    I read the Newman Haas paper. Does the 25Nm torque for Indycar come from this paper?
     
  12. Adrianstealth

    Adrianstealth Registered

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    thank goodness we can set our ffb systems to our preferred power setting in sim racing ....one of the perks hey
     
  13. DrR1pper

    DrR1pper Registered

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    Adrian, have you had the chance to start putting the new OSW kit together yet? If so, can we see some pics if possible/convenient please? :)
     
    Last edited by a moderator: Dec 8, 2015
  14. metalnwood

    metalnwood Registered

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    I think the increased resolution becomes beneficial to FFB controller, not necessarily so much to the game.

    A g25 has much less resolution but we seemed to be able to point it in the right direction and make fine changes. The FFB controller is using that extra resolution more often and resulting in smooth ffb, better ability to do its filters etc. At least that is my understanding.
     
  15. Joe

    Joe Registered

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    Encoder rate is for rating read-in steering position (user input) into the game. It is not "controlled".... I see nothing to do with controller. 5000PPR is overkilled, imho.
    Using the chart posted by Dr1pper, at 240rpm = 3.6 degree per frame (2.5 ms). FFB update rate 400 Hz. On encoding rate = 360/5000 = 0.072 degree per coded, that is 50 times higher than the 3.6 degree (FFB can update each time at that speed). So given, 2.5 ms time, 59 of counts will not be used in sim. they just waste...
     
  16. metalnwood

    metalnwood Registered

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    Yes, that was my point with the g25. As far as positional data getting back to the sim too much can be a waste but that was not what I was referring to when I was talking about the ffb controller.

    In the context of OSW the FFB controller is the MMos board and that also reads the encoder and does calculations based on it for some of the filters etc. The MMos board can make use of the addition encoder resolution and this is why people going from the mige with 2500 to 5000 encoder notice a difference with the same games. Not necessarily because the game uses all that extra resolution but because MMos board can. This is what I have heard discussed in the past.

    Beano might be able to add more there.
     
  17. Markj

    Markj Registered

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    Just wanted to say thank you for the responses to my post a page or so back, very useful info and advice :)

    Lots to mull over and things are obviously still moving on too with new motors and bits coming along all the time, tricky deciding when and what to jump in with. I'm pretty sure the AF would be absolutely fantastic for my needs, it's just deciding if the OSW is the better bet and worth the risk of assembly and setup time/issues over plug and play. Amazing that we have these options though, watched a program last night that showed Formula One on the ZX spectrum 48k my first driving game, we've come a long way :D
     
    Last edited by a moderator: Dec 9, 2015
  18. Joe

    Joe Registered

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    I take back. Just realized the 240rpm is very extreme case for steering. I will think 99% of time steering speed would be over 20 times slower.
    Thus, one could feel a diff between 10,000 PPR and 5000 PPR on FFB.

    On torque curve, as shown in the charts, below 100rpm we see no diff between OSW and AF wheel. I now believe very little notice diff on FFB feel between them in normal steering (except for high speed steering > 100 rpm).
     
  19. mimeitakashi

    mimeitakashi Registered

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    hiļ¼Œtraind
    You set up osw yet? If I'm not sell, you can consider my kit, the price is estimated to be the world's cheapest.

    http://www.mimeitakashi.icoc.cc/

    using Argon drives with mige motor($1860+300 Shipping)*
    and drives manufactured in China with mige motor(5000PPR)($1200+300 Shipping) ,
     
  20. thenic123

    thenic123 Registered

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    I have sent a pm to Beano about a month ago but go no reply.

    I have put my name down for a kit from Ollie. Might take awhile to get one. Thats OK, i can save the coins
     

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