[ODE] lib question

[Ignacio García Fernández]

What you are experiencing is called numerical unstability.

Let's do a test. Instead of increasing masses, sibstantially reduce the
stesize of your simulation. Say, divide it by 10 or by 20. And tell us
if this also solves the problem.

The reason is that the frequency of the movement of the low mass body is
very high, and the stepsize is not small enough to describe the
solution.

Hope this helps

Ignacio

El mar, 13-06-2006 a las 14:46 +0200, LR escribió:
> Hy,
>  
> I'm always trying to understant why low mass geoms crash the
> simulation.
>  
> A question : I'm using a plugin system: core is running simulation and
> plugins can act on the core and on ODE. i built ODE ReleaseLib then
> ODE code is embedded in each plugin and in the core.
> I know it's not a good solution but at this time it's easier for me.
>  
> My question is : 
> Does ODE keep "global" simulation variables (in this case it's normal
> my simulation crash : plugins variables does not contains good
> values), or does ODE keep all its variables inside an world object ?
> (in this case pfouuu i don't understant what happend).
>  
> Changing the mass resolves all my problems (it seems ...) but it's not
> normal i must enter something like 0,500 kg for a little robot
> wheel ....
>  
> A precision : when plugins are mounted, core gives pointers to created
> objects to the plugin
>  
>  
> Laurent.
>  
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-- 
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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