How PISCATUS^3D works

There are five main software elements that make PISCATUS^3D work.  These are:

• SeaLog
• Shared Memory
• SeaDBLog
• Firebird Database Server
• PISCATUS^3D 

The relationships and flow of data between the various PISCATUS^3D elements is shown below.  Data is given out from the various electronic equipment onboard the boat in NMEA format.  Each of these data output stringss are fed into a Data Multiplexer which combines all the NMEA sentences into one data stream.  This data steam is then fed into the PISCATUS^3D computer via a single COM port and is received by SeaLog.

SeaLog is a stand alone program separate from PISCATUS^3D .  SeaLog picks out the various NMEA sentences it has been configured to recognize such as depth, position, boat heading, COG, SOG and net position, and writes these paramters to Shared Memory.  It also flags, or discards, errors in the incoming data such as an incorrect position from the GPS, or the sounder coming off the bottom and giving erroneous depth values.  PISCATUS^3D and SeaDBLog then both read the values from Shared Memory.  If a plotter is also installed on the same computer, they can access Shared Memory as well and use the parameters and values stored there.  At present, C-Plot Pro and SeaPlot Pro plotters are supported. 

Unlike Version 3 PISCATUS^3D Tide is now part of Sealog, this applies tide corrections to incoming sounder data.  This is standard with all PISCATUS^3D installations and does not require any additional setting up.  PISCATUS^3D Tide can also interface with TotalTide which has the worlds most extensive set of Tide stations. The TotalTide interface was primary designed for the UK market where the standard tide station selection is low. TotalTide is used by the UK hydrograhical office and is know as the most accurate available. The TotalTide application must be purchased seperately from PISCATUS^3D but is easy interfaced.

SeaDBLog writes depth information from Shared Memory to the PISCATUS^3D database file (C:\Program Files\SMI\Piscatus\Data\BATHYMETRY.FDB) using Firebird. The SeaDBLog service runs in the background and is called the ‘Sealog Database’ service in the lists of services running on the machine.

PISCATUS^3D also reads Shared Memory and takes the relevant bits of information, namely boat position and depth, to help it draw its 3D terrain maps. At the same time, PISCATUS^3D also accesses depth data stored in the PISCATUS^3D database so it has information to build the terrain surrounding the boat’s current position.

PISCATUS^3D Inshore Pro, DeepSea Pro and Classic all install from the same set of disks. The Permit Code you are given by Seabed Mapping when licensing the software determines what mode PISCATUS^3D will run in and whether any additional modules are activated.

PISCATUS^3D Navigator is another program that is opened from within PISCATUS^3D itself.  This program gives the user an overview of the world with coastlines, boat tracklines and high resolution global bathymetry maps.  PISCATUS^3D Navigator is standard with all PISCATUS^3D installations and does not require any extra installation steps.

PISCATUS^3D comes with datasets that cover the planet. This is a one nautical mile grid cell dataset of the planet based on satellite altimetry. This background dataset is kept separate from the boat’s actual soundings and once the boat collects real data this built in data is quickly enhanced.  

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