Hi all, On Mon, Aug 14, 2017 at 06:10:33PM -0400, Ron Bean wrote: > >In a car it is even easier. The car nav system KNOWS it must be on a > >roadway. The car's ground track (positional history) must be on a road. > > That's assuming the GPS company keeps their maps up to date (it doesn't > matter how often you update the maps in the device if the company's maps > don't keep up with reality). New roads appear, old ones occasionally get > moved. In a regular vehicle you can still look out of the window and see the GNSS fools you.
For autonomous vehicles we have seen that even with a rather expensive unit, that is fusing IMU with RTK, the position is not accurate enough. We see offsets of >10 m in urban areas due to multipath[1]. Thus, I believe, map matching with LIDAR, RADAR, Cameras, etc. is necessary to navigate an autonomous vehicle in urban areas. This allows, as a side effect, to detect spoofing. On ships RADAR is standard if visibility is low, but doesn't help if there are no obstacles above water. Best regards, Thomas [1] Fusing odometry information would help a bit. _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
