How can I tell when a vehicle stops for a very short time?
You can with good confidence only catch stops where a vehicle is idling (ignition on) that are twice the report interval so that two reports are sure to come in with the same location. Thus, with a two minute report rate, you can only be sure of catching a stop that is at least 4 minutes.
If a vehicle parks (ignition off), you can catch a 1 second stop, because the IGN off creates an event that is included in the report. However, if a vehicle stops for less than 2 minutes but leaves the engine on, it is virtually impossible to detect the stop. The following list includes ways to improve your chances of catching a short stop, but may lead to false positives due to stops at intersections and stops because of heavy traffic.
To improve the chances of detecting very short stops:
• | Add a sensor to the door and use a sensor report to see where the driver opens the door. |
• | Import every customer stop as a marker and change your vehicle settings to "Show stops at markers" when the speed is very slow (for example, 15-30 mph). A Stop or Marker report will then show all but the very shortest of stops. |
• | Reduce the report rate to 30 seconds. This costs more, and may still miss some stops. |
What does it mean when a vehicle is shown as Idle?
A vehicle is given a status of Idle when it the ignition is on and it is not moving. To determine that a vehicle is not moving, it must remain in the same place for a set amount of time. There are two vehicle settings that are used to tell when a vehicle remains in place for long enough to be considered idle:
• | Only show idle of length x minutes or longer: The default is 5 minutes. If the vehicle moves before this length of time elapses, it is not considered idle. To reliably determine that a vehicle has not moved, this interval should be at least twice the report interval, so that there are sure to be two reports in the same location. |
• | Vehicle is moving if it moves x feet or further: The default is 200 feet. If the vehicle reports a change in location less than this distance, it is not considered to have moved. This distance compensates for minor changes in location that are artifacts of the GPS signal. |
Why does my vehicle show as moving with a speed of 0?
For a vehicle to be shown as Idle, the vehicle must be idle for a set amount of time. When the vehicle's location has not changed but the set amount of time has not yet elapsed, the vehicle is shown as moving with a speed of 0.
You can change the time a vehicle must not move to be shown as idle using the vehicle settings. Note that changing this value also affects histories and reports.
Why didn't it work when I tried to poll my vehicle?
The most common reason that polling a vehicle fails is because of a firewall on the network of the carrier that handles messages from your units. When you poll a unit, the message you send to that unit must pass through the carrier's firewall. To make this happen, a "pinhole" in the firewall is opened for the message to the unit on your vehicle. This pinhole only remains open for an interval of 15 seconds to 2 minutes (depending on the carrier). If that interval is very short, the polling message may not succeed.
Another issue is the type of units you have installed on your vehicles. Some units types have limited accessibility.
Even if polling fails, vehicles generate reports automatically at very short intervals (typically every 2 minutes), so you always have a reasonably accurate picture of the position and status of your units.
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