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Rigidbody Fall Speed?

Discussion in 'Editor & General Support' started by jtman562, Jun 12, 2011.

  1. jtman562

    jtman562

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    How can I determine the speed at which an object with a Rigidbody falls?
     
  2. Jessy

    Jessy

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  3. jtman562

    jtman562

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    That's not what I want. My Rigidbody starts in the air. I want it to fall faster.
     
  4. Jessy

    Jessy

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    http://dictionary.reference.com/browse/determine

    Are you using definition 1? I don't think that makes sense – I figured you meant definition 2 – but if you're talking about 1, I'd look at these, and if that's not enough, please try to add clarity to your question so we don't give you unhelpful advice, and we don't waste our time in the process.

    http://unity3d.com/support/documentation/ScriptReference/Physics-gravity.html
    http://unity3d.com/support/documentation/Components/class-ConstantForce.html
     
    doublevjack likes this.
  5. jtman562

    jtman562

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    Got it. Thanks.
     
  6. onlyskate13

    onlyskate13

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    Like:
    Code (JavaScript):
    1. rigidbody.AddForce(1, -4300, 1);
     
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  7. LukeNukem44

    LukeNukem44

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    The question is straight forward. Setting a rb velocity is exactly that, setting it's velocity, which is a pretty standard thing to do. The question asks for a falling force, like the globals Physics gravity, but for individual Rigidbodies. I need this too. It is Completely stupid that Unity did not make the mass affect it's gravity value, like it does in real life. Higher mass objects accelerate quicker when falling. -- I'm going to put it out there that there is no solution to it. There's not one in this thread. -- Shame on Unity for making Physics gravity a single global value.
     
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  8. LukeNukem44

    LukeNukem44

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    I'm going to post the solution, which I spent the last hour working out, in a new thread.
     
  9. mountblanc

    mountblanc

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    Looking forward to the answer as i noticed some objects with bigger mass starting to fall way to slow.
     
  10. LukeNukem44

    LukeNukem44

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    mountblanc likes this.
  11. LukeNukem44

    LukeNukem44

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    Yeah I noticed that too. Strange.
     
  12. mountblanc

    mountblanc

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    Thanks!
     
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  13. chelnok

    chelnok

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    Lets go deeper; blame Galileo. Source:
     
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  14. mountblanc

    mountblanc

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    In the real world, we have things like air resistance.
     
  15. mountblanc

    mountblanc

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    And by real i mean on earth yea the moon is real as well but all of us live on earth not on the moon. And my game for one is earth related.. And here on earth In practice, what you notice is that air friction makes less difference for the heavier object. So it would be nice to have that in the game as well. Because i want a peace of paper fall slower then a bowling ball.
     
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  16. chelnok

    chelnok

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    True. Are you using Drag property? It's for air resistance.
     
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  17. mountblanc

    mountblanc

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    Hmm Interesting i assumed incorrectly it was drag on a collider. I'll go tinkering with it.
     
  18. leventalpsal

    leventalpsal

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    This is not correct. Gravity force on higher mass will be higher but since acceleration = force / mass ; higher mass objects will have the same fall acceleration. The thing that makes the difference is air resistance or drag which can be simulated with rigidbody.drag in Unity. If you want the objects fall faster without adding external force, you should decrease the drag. If there is a feather or paper that should fall slowly, the drag should be increased.
     
  19. Neilpogi

    Neilpogi

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    i am from 2022 lol
     
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  20. arkano22

    arkano22

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    Hmmm... the mass of an object does not affect how fast it falls. Gravity is not a force, it’s an acceleration.

    Place a feather and a 100kg steel ball in vacuum, at the same height from the floor. Then let them fall, they will hit the floor at the exact same time.

    This only works in vacuum of course, otherwise the feather will fall slower due to air resistance (drag). Mass has nothing to do with this.

    So Unity’s approach is 100% correct: gravity is an acceleration (-9.81 m/s^2 on Earth) and affects all objects equally.

    If you want to have different gravities for different objects, it’s perfectly doable too: just add some downwards velocity each FixedUpdate().