How do automatic audio stop announcements on buses work?
Announcements are triggered through data processed by the GPS satellite antenna on each bus, as well as schedule and spatial data associated with our “bus stop intervals”. Each travel path from an origin bus stop location to any other subsequent bus stop location is surveyed in a staff car (again with a GPS antenna) – recording a distance travelled (odometer reading in feet), a compass bearing upon arrival (90 degrees due east), and the specific latitude/longitude coordinate of the staff car when stopped at the bus stop location. For example, the staff car first collects the coordinates for an origin bus stop (like southbound on Junction Road at Old Sauk, for Route 15), and zero out the odometer data. The staff car then drives to the next stop, on Junction across from the City Center West building, and collects how far this distance was (853 feet), what the heading was once stopped (153 degrees), and the coordinates of this stop. By populating all the possible intervals between bus sto
