GoKart Mod Tweaked

Discussion in 'Car Models | Physics' started by cercata, Jul 10, 2017.

  1. Johngrim64

    Johngrim64 New Member

    Joined:
    Jul 10, 2017
    Messages:
    9
    Likes Received:
    0
  2. cercata

    cercata Member

    Joined:
    Jul 6, 2017
    Messages:
    76
    Likes Received:
    27
    Location:
    Bilbao
    I'm playing with the tyre model and the suspension.
    The results in less powerfull karts seem very good to me.
    These are the karts ordered by power/mass ratio:
    • 270cc -> 8bhp, 150kg
    • 390cc -> 12bhp, 150kg
    • 250cc -> 28bhp, 143kg
    • 50cc -> 13bhp, 70kg
    • 100cc -> 22bhp, 71kg
    • 125cc -> 31bhp, 71kg
    • 125cc shitfer -> 41bhp, 74kg
    The 390cc is very close to the real one I have driven in OcioKart (http://www.ociokart.com/, IngeKart/Guenes)

    Have you driven a 125cc 2-strokes kart IRL ? I'd like to have feedback to see the differences, and see if I can improve it.
     
  3. garyjpaterson

    garyjpaterson Member

    Joined:
    Jun 28, 2017
    Messages:
    97
    Likes Received:
    99
    Bear in mind with a 70KG driver, the 250cc kart has a better power/weight ratio than the 50cc one.
     
  4. cercata

    cercata Member

    Joined:
    Jul 6, 2017
    Messages:
    76
    Likes Received:
    27
    Location:
    Bilbao
    Yeah, I know, but it's more like the 50cc is a sports car, and the other a powerfull berlina, so I liked more that order ... even if "the berlina is faster"

    Edit:In fact, looking at the power.lut, I see it's not 13bph, but 13,48hp on the wheels ... isn't it ?

    0|0
    1000|7
    8000|11
    12000|8
    13200|4
    14400|0

    But still slower than the 250cc one
     
    Last edited: Jul 21, 2017
  5. garyjpaterson

    garyjpaterson Member

    Joined:
    Jun 28, 2017
    Messages:
    97
    Likes Received:
    99
    Yeah just seems strange listing the weight of a kart without driver given it makes up 50% of the on track weight.
     
  6. Johngrim64

    Johngrim64 New Member

    Joined:
    Jul 10, 2017
    Messages:
    9
    Likes Received:
    0
    The AI is alot better and up to speed.The 125 kart is good and fun.You asked me to compare to real life kart.The game kart behaves like a small light vehicle with a fully locked diff.A real kart lifts the inner rear wheel on corners to allow it to turn and not scrub the rear tyres because of the fully locked or no diff.Im not sure the game engine can simulate this.That is not to say the mod is not good I find it fun to drive.
     
  7. cercata

    cercata Member

    Joined:
    Jul 6, 2017
    Messages:
    76
    Likes Received:
    27
    Location:
    Bilbao
    Your feedback is very wellcome, I find it fun to drive also, but if we make it more real, I think it will be better.

    In theory, the differential is locked in the kart, so the four wheels are forced to turn at the same speed:

    [DIFFERENTIAL]
    POWER=1.0 ; differential lock under power. 1.0=100% lock - 0 0% lock
    COAST=1.0 ; differential lock under coasting. 1.0=100% lock 0=0% lock
    PRELOAD=103 ; preload torque setting


    Maybe what you feel is because of the suspension ? Kart's don't have, but with assetto's suspension.ini I try to emulate the chassis rigidity.
    I made some changes to making it oversteer, because my feeling is that karts oversteer a lot.
    What do you think ?

    Try these Karts with much harder suspension and less grip:
    https://drive.google.com/open?id=0B6sqU0hVhdarajFVUmFIWUNYN0E

    I'm thinking about adding more grip to the 100cc, 125cc & 250cc karts, since normally they should have better tyres ...
    Edit: Aready done, and much more hard suspension, almost infinite xD
     
    Last edited: Jul 25, 2017
  8. cercata

    cercata Member

    Joined:
    Jul 6, 2017
    Messages:
    76
    Likes Received:
    27
    Location:
    Bilbao
  9. GT VIRUS

    GT VIRUS Member

    Joined:
    May 22, 2017
    Messages:
    38
    Likes Received:
    16
    Location:
    Location
    For the physics, give a live axle a go. I am unsure if AC can simulate the inner-rear wheel lifting, but try adding a large amount of caster to help. Karts can run over 10 degree's caster, I believe the latest arrow bumped it up to 18 degree's.

    The engine's feel fine to me. I've driven several racing karts, and I can't pick too much wrong.

    For the tyres, in general the 100'c run relatively hard tyres (but still much softer than rentals), 125's running mediums and shifters softs. But that varies soo much between countries, so I would give them all the option for hard/medium/soft
     
  10. cercata

    cercata Member

    Joined:
    Jul 6, 2017
    Messages:
    76
    Likes Received:
    27
    Location:
    Bilbao
    I don't understand ... whats "live axle" and "caster" ?
    And, an unrelated question, what % of the weight of the kart goes on the front wheel-train?
    Edit: I have seen what caster is, but I thinks assetto doesn't have it ...
    Edit2: Ok, in the "Kunos Suspension editor" it shows me a caster of -15, but I cannot change the parameter, it's a function of the suspension geometry.
    Edit3: Ok, I can play with caster at my will !!!!!! I can make a chopper xD

    You read my mind ... I was thinking in doing that after migrating to tyre model 7.
    Now I have 4 tyres, and those are the equivalences.
    • 270cc & 390cc(rentals): Superhard
    • 50cc: Hard
    • 250cc & 100cc: Medium
    • 125cc & 125cc shifter: Soft
    All cars will have al tyres available, but by default the ones they have now.
    At the moment I only changed the grip, but I'll have to change also the wear curve ...
    What do you think ?

    Hey what is the radius of the wheels in you car ? And what's its weight ?
    How did you calculate FZ0 ? Is it in Newtons ?

    Looking at the Formula K example, its more than the car weight divided betwen the weels, so maybe the reference is at a certain speed with aerodinamic load ?
    Or a value given by the manufacturer ... related to load Index ?

    Can we debug FZ ?
     
    Last edited: Jul 28, 2017
  11. garyjpaterson

    garyjpaterson Member

    Joined:
    Jun 28, 2017
    Messages:
    97
    Likes Received:
    99
    Weight is under 300kg inc driver, overall tyre radius is around 0.23m.

    As for FZ0, I've just lowered it slightly from the Tatuus (lighter car, but a fair amount of downforce still), and kept front/rear equal as unlike the Tatuus it used the same tyres front/rear. Still waiting on proper tyre data from the team, so I just tuned it by feel with dx/dy_ref to get the correct lat/long acceleration until then.

    I guess aero load has to be taken into account, no use having tyres designed for one load if in reality there it is far greater.
     
  12. cercata

    cercata Member

    Joined:
    Jul 6, 2017
    Messages:
    76
    Likes Received:
    27
    Location:
    Bilbao
    Assetto support cars with the engine in the back ?

    The engine takes damage when I hit the front of the Kart instead of when I hit the back.
     
  13. garyjpaterson

    garyjpaterson Member

    Joined:
    Jun 28, 2017
    Messages:
    97
    Likes Received:
    99
    Does AC support rear engine cars? Porsche 911 :p

    Does the damage system support rear engines? Dunno, the damage system is pretty crappy, most cars will destroy the engine if you have a big enough head on.
     
  14. cercata

    cercata Member

    Joined:
    Jul 6, 2017
    Messages:
    76
    Likes Received:
    27
    Location:
    Bilbao
    :whistle::whistle:

    So, in the game, you only can put the CoG backwards?
     
  15. garyjpaterson

    garyjpaterson Member

    Joined:
    Jun 28, 2017
    Messages:
    97
    Likes Received:
    99
    You can put it wherever you want, to match the real car, meaning it will drive like a rear engine car. Completely separate from the damage system.
     
  16. GT VIRUS

    GT VIRUS Member

    Joined:
    May 22, 2017
    Messages:
    38
    Likes Received:
    16
    Location:
    Location
    It's a mid engine technically, as the engine is about 20cm infront of the rear wheels. Unsure if it can be offset, but the engine's weight is around 20kg (depending on the engine) and to the right of the driver. CoG of a kart (including driver) is just off to the right of centre, just infront of the driver, and at about the bottom of the steering wheel
     
  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice