Static Objects and Collisions

[YAN3]

Hello everyone. I am using Bullet to check for collisions between objects like boxes and cylinders which are supposed to be modeling a robotic arm. Collision detection seems to be working fine, but there's something weird that I noticed. I had set all object masses to zero because I'm not really interested in moving them. I just want to detect when things collide. But when there is a collision, objects seem to shift in location and orientation a little bit, giving weird results. Is there a way to make sure that none of them moves at all upon collisions, but such that I still check for collisions? Thanks a lot in advance.

Regards,
Nick

[sms]

I had set all object masses to zero because I'm not really interested in moving them.

I don't know how things work in Bullet but generally in physics simulation immovable objects should have mass equal to some value that represents "infinity". The inverse of the mass is zero.