Strange behavior due btHingeConstraint

[svedach]

Tell me what the problem is. Create cylinders btCylinderShape, hard body to them, they turn to the desired angle. Next to join the box (btBoxShape) as a solid. Connection btHingeConstraint. Before running simulation cylinder is at a predetermined angle of rotation, at start abruptly becomes to horizontal position and then becomes relatively slowly into place. After that, everything works well.

[Basroil]

Sounds like you're passing in an undefined variable somewhere in your code and the hinge is trying to hit an impossible target.