Increase GPS random walk to better reflect reality

[klaxalk]

[spurnvoj]

How much do you want to change it? These are the values which are there now

          <plugin name='gps_plugin' filename='libgazebo_gps_plugin.so'>
            <robotNamespace/>
            <gpsNoise>1</gpsNoise>
            <gpsXYRandomWalk>2.0</gpsXYRandomWalk>
            <gpsZRandomWalk>4.0</gpsZRandomWalk>
            <gpsXYNoiseDensity>0.0002</gpsXYNoiseDensity>
            <gpsZNoiseDensity>0.0004</gpsZNoiseDensity>
            <gpsVXYNoiseDensity>0.2</gpsVXYNoiseDensity>
            <gpsVZNoiseDensity>0.4</gpsVZNoiseDensity>
          </plugin>

[spurnvoj]

Datasheet for Neo-M8N chip used in most of the pixhawk GPS receivers says that the horizontal precision is 2.5 m (GPS+GLONASS). So I can update it to this value. Is it enough?

[klaxalk]

I think 2.5 m is the "optimistic" value. Now the question is, wherher we should not simulate with more pessimistic values, to prevent any surprises in the real world.

[spurnvoj]

Is this is valid? Should I change the GPS horizontal precision to 2.5m?

[klaxalk]

Ye, I still think the normal GPS random walk should be more visible.