Vessel Insight provides a basic, automated voyage history service to enable basic voyage-focused usage scenarios for the customers vessels and offers:
- Vessel Positions
- Voyage history tracking
- Weather information
- Distance calculation
The service is using different data sources like, AIS, weather and distance information to provide and calculate details of a vessels voyage. To enable an automated approach in Vessel Insight, certain assumptions to determine start and end time for voyages are taken and they are to be considered as approximates. These assumptions are explained later in this article.
Tracking the voyage history of a vessel can often be complex and challenging. In many cases, accurate tracking requires noon report data or voyage planning data.
Tracking
The flow of the voyage tracking is as follows:
- Voyage start time is recorded automatically.
- AIS positions is read from AIS provider hourly.
- Those positions are matched with forecasted weather data from our weather provider and recorded every 2nd hour.
- Voyage end time is tracked automatically, voyage is considered to be "In progress" when end time is not present.
Location decoding
The raw destination location is decoded with UN/LOCODE to provide a readable destination name in voyage records.
Distance calculation
Distance is calculated based on a 3. party source that provides standardized voyage distance in nautical miles. We use this in our history records after voyage end and in calculation of voyage end time.
Weather
Weather data is recorded from a 3. party service and and the provider might change over time.
Assumptions on voyage start and end timing
Certain assumptions is taken to enable an automatic voyage history generation based on AIS data for vessels.
Start Time for a New Voyage
- Condition: When the destination in the AIS message changes.
- Additional Criteria:
- Navigational Status is “under way using its engine” (0).
- Speed is greater than 1 knot.
- Action: Set the voyage start time to the AIS timestamp.
End Time for a Voyage
- Condition:
- Distance to destination is less than 1 nautical mile, or
- Navigational Status is “Anchored” (1) or “Moored” (5).
- Additional Criteria: Speed is less than 1 knot.
- Action: Set the voyage end time.
Due to these assumptions you may find situations where a vessel has ended a voyage and not starting a new one immediately.