Re: [Paparazzi-devel] AGL and NavSetGroundReferenceHere()

[Martin P]

Thank you, I have put it into the WIKI under GCS.  
I hope this is the right place. 

I have tried it, now I am only 12m above ground. 

Greetz, Martin 

-------- Original-Nachricht --------
> Datum: Sun, 09 Aug 2009 23:29:24 +0200
> Von: Pascal Brisset <address@hidden>
> An: address@hidden
> Betreff: Re: [Paparazzi-devel] AGL and NavSetGroundReferenceHere()

> Hi,
> 
> you need
> 
>     http://dds.cr.usgs.gov/srtm/version2_1/SRTM3/Eurasia/N47E016.hgt.zip
> 
> in data/srtm/
> 
> --Pascal
> 
> Martin P wrote:
> > Hi, thanks for answering!
> >
> > What I call AGL: What is displayed in the GCS. 
> > SRTM: I have a file N47E011.hgt.bz2.  
> > I am at N47.82 and E16.88. Does this file cover my location? 
> > If yes, I would say it is available. 
> > If no, where do I get it from? I did a "Google Maps fill". Btw, the
> terrain here is dead level.  
> >
> > Greetings, Martin 
> >
> > -------- Original-Nachricht --------
> >   
> >> Datum: Sun, 09 Aug 2009 17:07:54 +0200
> >> Von: Pascal Brisset <address@hidden>
> >> An: address@hidden
> >> Betreff: Re: [Paparazzi-devel] AGL and NavSetGroundReferenceHere()
> >>     
> >
> >   
> >> Hi,
> >>
> >> what do you call AGL ?
> >>  - in the airborne code, NavSetGroundReferenceHere() sets ground_alt to
> >> the current altitude (common_nav.c:84).
> >> This variable is for example use in HOME mode (nav.c:370) or in the 
> >> Takeoff and Final block of the basic.xml flight plan.
> >>  - in the GCS, AGL is computed by subtracting the terrain altitude
> (from 
> >> the SRTM model ... if the file is available in data/SRTM) from the 
> >> current altitude
> >>
> >> --Pascal
> >>
> >> Martin P wrote:
> >>     
> >>> I use a flight plan with goround_alt=0 (derived from basic.xml).
> >>> After calling NavSetGroundReferenceHere(), I would expect that the AGL
> >>>       
> >> is 0. 
> >>     
> >>> Instead, it is the altitude above sea level. The GPS mode is 3D and
> the
> >>>       
> >> AGL varies within 3 or 4 meters. 
> >>     
> >>> Is this the way it should be? Should I set the ground_alt to the
> actual
> >>>       
> >> altitude? 
> >>     
> >>> _______________________________________________
> >>> Paparazzi-devel mailing list
> >>> address@hidden
> >>> http://lists.nongnu.org/mailman/listinfo/paparazzi-devel
> >>>   
> >>>       
> >>
> >> _______________________________________________
> >> Paparazzi-devel mailing list
> >> address@hidden
> >> http://lists.nongnu.org/mailman/listinfo/paparazzi-devel
> >>     
> >
> >
> > _______________________________________________
> > Paparazzi-devel mailing list
> > address@hidden
> > http://lists.nongnu.org/mailman/listinfo/paparazzi-devel
> >   
> 
> 
> 
> _______________________________________________
> Paparazzi-devel mailing list
> address@hidden
> http://lists.nongnu.org/mailman/listinfo/paparazzi-devel