[ODE] How to detect unstability / crash

[Patrick Enoch]

Hi,

I check whether the coordinates/velocities are "in range". In my case  
that means:
abs(pos.x/y/z) < 1e10
abs(lin_vel.x/y/z) < 1e6
abs(ang_vel.x/y/z) < 1e6

of course, those values will depend heavily on your application. The  
checks are done before (in case bad values are fed to the stepper)  
and after the quickstepper.

IMO forces are a bad idea, because the inv_mass plays a role in  
translating that to a velocity. Heavy object + lots of force = little  
velocity. ( dv = F/m*dt ).

On 18.06.2007, at 18:28, Ignacio García Fernández wrote:

>
> Hi,
>
> I'm interested in detecting when the application is going to crash,  
> or to
> become unstable. This would allow to reset the simulation before this
> happens, possibly causing application crash.
>
> Severl ideas come to me, but they do not seem too efficient; eg.  
> monitoring
> all the joint forces or the constraint violations.
>
> Does anybody have any idea on how to do this?
>
> Thank you in advance
>
> Ignacio
>
> -- 
> May the source be with you
> ---------------------------------------------------------------
> Ignacio García Fernández                  Instituto de Robótica
> ignacio.garcia_at_uv.es                 Universidad de Valencia
> http://robotica.uv.es/~ignacio/                Tlf. 96 354 3671
>
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