That statement waits for 10 seconds to let the GPS position stabilize
before setting the coordinates and height of the Home waypoint.
Hope this helps.
[mailto:address@hidden On Behalf
Of Helge Walle
Sent: Thursday, 17 June 2010 8:57 PM
Subject: [Paparazzi-devel] Re: Flight plan altitude data.
Thanks a lot, Thomas !
I followed your advice, and this works just fine in Paparazzi.
I compared the elevation data to places in my area with known height above sea
level, and they are good to within a few meters from my local maps and also to
what the gps says.
These data also made me understand how AGL works.
Still I would be interested in some understanding of the <while
cond="LessThan(NavBlockTime(), 10)"/> statement, if anyone
could enlighten this.
looks like original data from USGS doesn't cover your area.
But you can download http://www.viewfinderpanoramas.org/dem3/P31v2.zip
- unzip P31v2.zip, cd P3, bzip2 *,mv * $PAPAHOMEDIR/data/srtm and try again.
Am 16.06.2010 23:07, schrieb Helge Walle:
I live at lat0=60.381221
lon0=5.152867 in Norway. I can not find any SRTM data for the area
where I live.
I am working to understand the altitude
data in the flight plan, and also the "AGL" value in the GCS. I
have searched through the mailing list for explanations; found some, but still
I have a way to go.
The following is part of my current
<block name="Geo init">
<while cond="LessThan(NavBlockTime(), 10)"/>
<set value="ground_alt" var="waypoints[WP_TD].a"/>
<set value="ground_alt+10" var="waypoints[WP_AF].a"/>
Does the statement <while cond="LessThan(NavBlockTime(), 10)"/> specify the
time of determining "ground_alt" ?
How is this statement explained ?
How is "AGL" in the GCS computed? Is it the altitude given
by the GPS minus "ground_alt" ?
Is "Alt" in the GCS the altitude given by the GPS at any time ?
Thank you for any help,