[1.9.8] NaN Hingeconstant Bug

[hiltropper]

With default hinges (hinges with Hingeconstant = NaN) there can appear some strange effects
I built an engine and suddenly the engine ran without any reason, changeing the const of some of the hinges helped
attached an example scene

[PhunWars]

Hmm, "Axle impulse" 's value changes when you press a...probably hinges give some kind of energy to the engine

[emilk]

This is related to viewtopic.php?f=11&t=4481

It is very difficult to optain both stiffness and stability - a compromise is always needed. In this case, lowering the default constraint strength from 1e8 to 1e7 N/m would suffice, but would make hinges weaker. Maybe it is a fair trade, though.

Please experiment with Sim.solveConstant, and see if there is a good value that does not cause instabilities, but that is reasonably stiff. 1e6 or 1e7 is probably around the desired values.

For reference, a hinge constant of 1e7 would make a hinge stretch about a milimeter for every 1000 kg it is loaded with.

[hiltropper]

yes, i think it's okay that way