[Qgis-user] qgis and gps in real-time

[Martin Dobias]

On Fri, Mar 7, 2008 at 1:47 PM, Chris H <chris123 at magma.ca> wrote:
> On Friday 07 March 2008 05:17:23 am Luca Casagrande wrote:
>
>  > Hello Andrea.
>  >
>  > I hope not be OT, but here [1] you can find an application similar to the
>  > one you are going to start.
>  > In that example, the tracking system is made with a Web Application but it
>  > can be expanded via Qgis, for the
>  > reason that the most import thing is to update the data from the receiver.
>  > Once you have the data updated at a certain interval, you can access them
>  > with anything (for examples a Qgis plugin that
>  > will reload data at a selected interval).
>
>  I think this is not as simple as described. If realtime tracking is required
>  and to be displayed, then several things need to be considered. The gps data
>  will be sent as either NMEA 0183 or NMEA 2000 that is known as those are the
>  only available outputs. Most likely NMEA 0183. Then the data needs to be
>  captured by receiver. The data is typically in text format or pending on the
>  model. See: http://www.gpsinformation.org/dale/nmea.htm

In case you don't need it on windows platform, you can simply use gpsd
[1] which makes acquiring of position quite simple: you just use
socket to connect to a known port where you can read parsed
information in uniform way from nearly any type of GPS. Then it's just
matter of displaying it on the map canvas in QGIS and that's
relatively simple.

Anyway, creating a parser for NMEA format is not hard since it's
simple text protocol... There are few challenges if you want to make
it more universal since some GPS devices have slight changes in the
protocol.

Martin