[ODE] request: dBodyAddRelTorqueAtPos()

[Luke Palmer]

benny writes:
> Hm....
> But how can I calculate the external force+torque that will cause a
> body to rotate around a specific point/axis?

I think you misunderstood his reply.  In the physical world, there is no
such force that will do that.  A body, in the real world, always rotates
about its center of mass.

The force you're trying to calculate doesn't exist :-)

What's the context?  What are you trying to do?

Luke

> 
> Thanks
> 
> 
>    -------Original Message-------
>    > From: Amund Børsand <amund at offroad.no>
>    > Subject: Re: [ODE] request: dBodyAddRelTorqueAtPos()
>    > Sent: 09 Mar 2004 13:51:30
>    >
>    >  A body will always rotate around it's center of gravity, which in ODE
>    >  always is 0,0,0 in body coords. But you can use a joint to rotate it, or
>    >  move everything else (collision geometry, mass, joints) to get the CG
>    >  where you want it.
>    >  
>    >  Benny Kramek <benny at kramekweb.com> skreiv:
>    >  
>    >  > hm... Then how can I get a body to rotate around a specific point/axis?
>    >  >
>    >  > Thanks
>    >  >
>    >  > Amund Børsand wrote:
>    >  > > That doesn't make sense, torque is not applied anywhere, i.e. it doesn't
>    >  > > matter where you apply it :)
>    >  > >
>    >  > >
>    >  > > Benny Kramek <benny at kramekweb.com> skreiv:
>    >  > >
>    >  > >
>    >  > >>Hi, can the function dBodyAddRelTorqueAtPos() be added to the ODE API,
>    >  > >>and implemented please? :)
>    >  > >>
>    >  > >>--
>    >  > >>Benny Kramek
>    >  > >>   http://benny.kramekweb.com
>    >  > >>   benny at kramekweb.com
>    >  > >>
>    >  > >>
>    >  > >>_______________________________________________
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>    >  > >>http://q12.org/mailman/listinfo/ode
>    >  > >
>    >  > >
>    >  >
>    >  >
>    >  > --
>    >  > Benny Kramek
>    >  >    http://benny.kramekweb.com
>    >  >    benny at kramekweb.com
>    >  >
>    >  >
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>    >  
>    >  --
>    >  Amund Børsand <amund £ offroad . no>
>    >  
>    >  
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>    -------Original Message-------
> 
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