How are Posted (Real) Road Speed overspeed events generated

What is Real Road Speed?

In order to accurately report overspeed and monitor driver behaviour, Smartrak needs to calculate and report Real Road Speed.

Real Road Speed provides the ability to understand when and where drivers are speeding in relation to the road speed of the actual road they are travelling on and not just 100 km/hr roads.  It ensures more accurate reporting of driver behaviour and under / overspeed events.

How do we calculate Real Road Speed?

  1. The tracking application detects a trip has started. (key on)

  2. Every 20 seconds a location/timer event will be generated. This event contains information like:

    1. Location

    2. Speed

    3. Time

  3. The system will perform a real road speed check

    1. If this event is above (or equal to) the posted speed limit + threshold (defaults to 5):

      1. Create overspeed event.

    2. If this event is below the posted speed limit + threshold and the previous event was an overspeed event:

      1. Create below speed event.

Limitations

Event Frequency

Each timer event is generated at a 20-second frequency. This frequency has an impact on a few things:

An overspeed period reports on:

  • Start time

  • End time

  • Distance

  • Min speed

  • Max speed

Due to the fact that we are using events at 20-second intervals, an overspeed period can inaccurately be reporting an overspeed state for up to 18 seconds.  Periods will only ever be a maximum of 20 seconds inaccurate.

Missing overspeed events

Since we are only taking a snapshot of the speed every 20 seconds the is the possibility of missing an overspeed period entirely if it falls within the 20 seconds between pings.