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Fixed Joint with Inertia Tensor

Discussion in 'Physics for ECS' started by argibaltzi, Oct 14, 2020.

  1. argibaltzi


    Nov 13, 2014

    2 cubes on top of each other (similar to the RigidBody joint setup in the example)

    I am trying to get a simple fixed joint working with inertia tensor X and Y set to 0

    When i try with inertia tensor to ON the joint doesn't work very well anymore, it seems to fold and eventually the 2 cubes will be in same position.

    With no inertia tensor the 2 cubes always seem to be on top of each other and move together as one

    Any ideas?
  2. steveeHavok


    Mar 19, 2019
    The Rigid Joint is working in 3D, however by setting the inverse inertia tensor in X and Y to 0 effectively stops the Joint from correcting the error.
    If you set only one body in the pair to have a tweaked inertia tensor the fixed joint should work.
    Alternatively, you can just a joint that focus on fewer axis (e.g. a limited hinge with zero limits) works are well.
    The best thing would be if you created your only Joint with a single angular Constraint atom that only worked on the remaining free axis of rotation.