Speeding Events Logic
GreenRoad has a 3-tier speed limit system:
Posted speed – The official speed limit of the current location sourced by GreenRoad's map provider. This speed limit reflects the speed limitation posted on each road.
Landmark speed – Managers can set a speed limit for a specific landmark via Central.
Fleet speed – The maximum speed allowed for fleet vehicles anywhere, that is set on a vehicle level by the fleet managers.
Note: for the posted speed only, managers can set a speed tolerance in % or km\miles. This means that posted speed events will take the tolerance into account.
How does it all add up?
At any point of GPS detection (frequency between checks is different between Edge and Mobile and can also be set differently per unit), our system validates the speed against all 3 limits and will use the lowest speed limit for determining a speeding event.
You should see an indication of which speed limit violation was happening in the alert report.
Note: Landmark Speed takes precedence over the area’s Posted Speed and Fleet speed. Meaning, a location’s Landmark Speed, if it is configured, will serve as the exclusive and effective speed limit, taking precedence over the area’s Posted Speed Limit
The following examples illustrate the logic:
Fleet speed – 60 km/h
Posted speed – 90 km/h
Landmark speed – 80 km/h
If a driver travels inside a landmark area at 85 km/h- that is, 5 km/h faster than the Landmark Fleet speed limit- the system will trigger a landmark speeding event.
If the driver travels anywhere else at 85 km/h- that is, lower than the Posted Speed limit but higher than the Fleet speed- the system will trigger a fleet speeding event.
How do we handle the grace period for drivers?
Another important element of our system is the grace we give drivers to lower their speed when we detect a speeding event.
Since there are a lot of nuances in roads (for example the crossing of speed limits) we have a built in 15 sec grace for drivers between getting the “Check your speed” note to the actual speeding event. In between we check GPS frequently and if the driver slows down below the speed limit, he\she will not get a speeding event on his\her record.