[ODE] Contact

[Mohamed I. Matar]

I have two cuboid, these cuboid should interact before touching. So I
created a buffer of thickness d around the cuboid and made ODE detect
collision, then I find the distance between contact point and cuboid,
apply my forces and do not connect the two bodies except when the
distance from contact to cuboid minus buffer equal zero, then I make
contact joint between bodies. The problem is, as usual penetration, I
changed ERP, Contact velocity, time step, .... but still. I need big
help in that. I thought of changing the contact passed parameters, but
what to? I thought of using soft boundaries, but I understand that
softness allow penetration but it applies a force depending on the
softness k value. Am I right?

My second problem in a very big list of problems :) :) is that I have
two types of bodies, one has buffer around them and the other not. When
one of type one contact with one from type 2 in parallel and although I
am not allowing creation of contact, it is created. So I was thinking,
can I change geometry during simulation and how will it affect the
simulation results. The reason for that is that I create the buffer by
changing the geometry to reflect this buffer and this buffer thickness
is as big as cuboid thickness, so I am afraid that the simulation result
will be nonsense

I need help with fine tuning the simulation parameters to avoid
instability and penetration and with ideas. I can send parts of code if
you want to take a look

Help please

Thanks in advance