<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
</head>
<body>
Everyone,<br>
<br>
I've just pushed an attempt to fix the false alerts by introducing
and applying a normalized GPS "signal quality" level from the
satellite count and HDOP.<br>
<br>
From analysis of my collected GPS data I've come to the conclusion
the HDOP isn't a reliable standlone indicator. I've seen coordinates
off by 8 kilometers with HDOP at 1.5, which should normally mean
"nearly perfect". Only by taking also the satellite count into
account, all false position readings could be filtered.<br>
<br>
<a class="moz-txt-link-freetext" href="https://github.com/openvehicles/Open-Vehicle-Monitoring-System-3/commit/8aa6004efbf39d87e3077d01c8fefda59496def0">https://github.com/openvehicles/Open-Vehicle-Monitoring-System-3/commit/8aa6004efbf39d87e3077d01c8fefda59496def0</a><br>
<blockquote><font face="monospace">GPS: add normalized signal
quality level, add web UI live status info</font><br>
<font face="monospace">Location: flatbed movement alarm only with
reliable positioning</font><br>
<br>
<font face="monospace"> New metrics:</font><br>
<font face="monospace"> v.p.gpssq --
GPS signal quality [%] (<30 unusable, >50 good, >80
excellent)</font><br>
<font face="monospace"> v.p.gpstime --
Time (UTC) of GPS coordinates [Seconds]</font><br>
<br>
<font face="monospace"> New configs:</font><br>
<font face="monospace"> [vehicle] gps.sq.good --
SQ level for location state "reliable", default 60</font><br>
<font face="monospace"> [vehicle] gps.sq.bad --
SQ level for location state "unreliable", default 40</font><br>
<br>
<font face="monospace"> New events:</font><br>
<font face="monospace"> gps.sq.good --
GPS position is now reliable</font><br>
<font face="monospace"> gps.sq.bad --
GPS position is now unreliable</font><br>
<br>
</blockquote>
For the Teslas I've added a simple 0/100 setting, and a satellite
count based calculation for the Jaguar. Btw, the Model S adaption
seems to lack handling for losing the GPS lock, and the Jaguar iPace
seems to lack setting the GPS lock at all.<br>
<br>
The quality level replaces the GPS lock status role for the location
module: no location changes or flatbed alerts will be emitted while
quality is "bad".<br>
<br>
The quality formula and thresholds work nicely for my region, please
test & report if changes are necessary. I've added the quality
level to the MP "L" message, so you can easily check your levels
from a daily data export. It's also included in the live widget of
the web UI's status page.<br>
<br>
Regards,<br>
Michael<br>
<br>
<br>
<div class="moz-cite-prefix">Am 02.04.22 um 21:30 schrieb Craig
Leres:<br>
</div>
<blockquote type="cite"
cite="mid:8827d248-5814-6fa0-c262-a955e5f840f7@xse.com">On 4/2/22
11:06, Michael Balzer wrote:
<br>
<blockquote type="cite">Your parking lot has pretty good GPS
reception with never less than 7 satellites in view, my case is
near the edge of GPS unusability with some periods of only 2
satellites in view.
<br>
</blockquote>
<br>
My condo has a detached two car garage and the walls and tar &
gravel roof are fairly RF transparent. My dev unit is in the spare
bedroom and there is aluminum (or similar) in the walls and roof
that does a good job of blocking both gnss and siriusxm satellite
radio so the antenna (attached to window blinds) does not have a
360° view of the sky. Essentially it can only see out the window
(which I believe has a UV coating that probably degrades the
signal some amount.
<br>
<br>
Craig
<br>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
Michael Balzer * Helkenberger Weg 9 * D-58256 Ennepetal
Fon 02333 / 833 5735 * Handy 0176 / 206 989 26</pre>
</body>
</html>