[ODE] Re: Bendy wheel problem

[McEvoy, Nick]

Nate Waddoups wrote:
>Is it just me, or are there two distinct 'bendy wheel' problems?

>One problem is a random-looking wobble that happens when the wheel's
>rotation speed gets too high; the other problem is that the wheel bends
>from its proper angle during cornering.  The former seems to be caused by
>a constraint that is too stiff (it looks a bit like an oscillation), the
>latter seems to be caused by a constraint that is too soft (it's just a
>smooth divergence from the desired orientation).

Yes, I get both problems !


>The latter is visible in Si's buggy-and-shadowing demo, and I wonder if it
>might be related to the suspension parameters of the hinge-2 joints.  
>They are supposed to soften up linear motion along the suspension axis,
>but do they (as an unintentional side-effect) also soften up the alignment
>constraints, allowing the wheel bend away from the desired orientation?

>Has anyone tried making the suspension really stiff, and if so does that
>help the second bending problem mentioned above?

Yes I have and no it does not. :(

Something I have not tried yet is to compile ODE as DOUBLE precision.

I might just have to take Michael Bickel's suggestion and "lock both axis of all 4(speaking of a 4 wheel-vehicle) hinge2 joints to match the orientation of the chassis".  A very nice demo avi by the way !

Nick