If you include the wheel mass as a separate object
supported by a tire spring then the major new thing
you get is the "Wheel Hop" mode.
This is resonance at 10 to 15 cycles per second of the
car and wheels system.
Controlling this mode to keep the tires
planted as much as possible is one of the jobs of the
shock absorbers. If you don't include the mode,
you don't need to do "fast bump" etc. modelling of the
shocks for example, because the car object (sprung mass)
won't usually move (or oscillate) that fast.
This mode is much higher than the frequency of the sprung mass
on the suspension springs, and so can give stability
or modelling trouble when integrating.
> > Hm, I have a setting in Racer which is close to this; debug.ini's
> > use_susp_as_load. If on, it skips tire rate and uses the suspension
> > instead (but still uses wheel mass to get the wheel's acceleration).
> > I know use tire rates again, btw. It just explodes a bit sooner.
> Are you trying to imply that even using implicit integration, using
> tire rates introduces instabilities into the sim?
a frequency then the dynamic mode just gets filtered out.
Kind of a "tree falls in the forest" type of thing:
If it goes into the integrator and doesn't come out can
you really say you are "modeling" it? ;)
- Matt