Hi Ugo,

I am by no means authority but this is the way I update parameters in my nodes:
Define node's member function, e.g.:
/////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 double param_;
 void
      updateParametersFromServer ()
    {
      nh_.getParam ("my_param", param_);
    }
and then constantly call it in that node's spin function:

      updateParametersFromServer ();

See also an attached example file.

Furthermore, I just recently stumbled upon
http://www.ros.org/wiki/dynamic_reconfigure which "facilitates dynamic
node reconfiguration". However I do not really understand in how far
is it different to conventional updating of parameters as discussed
before. But maybe Blaise can tell here more.

D.
On Mon, Apr 19, 2010 at 6:56 PM, Ugo Cupcic <ugo@shadowrobot.com> wrote:
> Hi,
>
> I'm currently setting the parameters for the controllers (PID and so on)
> via a message (I have a subscriber which updates the values when it
> receives the corresponding message).
>
> It works well, but I wanted to know what was the recommended way of
> doing that in ROS. Is it better to do it using parameters? (But then how
> can I  change the corresponding values when the parameters are updated?)
>
> Cheers,
>
> Ugo
>
> --
> Ugo Cupcic         |  Shadow Robot Company | ugo@shadowrobot.com
> Software Engineer      251 Liverpool Road
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-- 
MSc. Dejan Pangercic
PhD Student/Researcher
Computer Science IX
Technische Universität München
Telephone: +49 (89) 289-17780
E-Mail: dejan.pangercic@in.tum.de
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