Official maps in electronic or paper form are created by the national authorities of the Topographic or Hydrographic Services authorized by the government. These services are responsible for the accuracy and reliability of the map data. They are also responsible for timely updating of maps..
Official and commercial electronic maps for GPS-navigators, selection of electronic maps, application of raster maps.
The presence of official sea charts on large vessels of the professional fleet is mandatory in accordance with the SOLAS (Safety Of Life At Sea) International Convention. Safety requirements for international maritime and aviation communications in conditions of increased traffic intensity have led to the need to regulate the introduction of electronic maps by relevant international institutions.
This issue was particularly acute in connection with the introduction of electronic cartographic systems in the navy. As a result of the work of a number of committees of the International Hydrographic and Maritime Organizations (IHO, IMO) in 2000, the S-57/3 standard for the transmission of digital hydrographic data was developed and approved. It is agreed that official electronic cards should be supplied in S-57/3 standard format. Display and content of electronic maps in an electronic cartographic and information system (ECDIS / ECDIS) must meet the specifications of another standard – S — 52.
The IHO and IMO guidance documents require that the ECDIS installed on board the ship uses official electronic cards (electronic card database) supported by automatic proofreading and has redundancy in case of failure. Only in this case, the presence of paper navigational charts on board a seagoing vessel is not mandatory. This is the conceptual basis for replacing traditional paper maps with the ECDIS system, which is the latest and most effective navigation tool. At the same time, the SOLAS convention defines ECDIS in conjunction with a database of official electronic cards as the legal equivalent of an adjusted paper card.
It is interesting to note that since 1995, when the operational standard for ECDIS was adopted, the sailors were seriously discussing whether the paper card would live another 10 years. But real life dispelled this overt optimism. What is the reason? It is enclosed in a small coverage of water areas with official electronic maps of the required scale. So, according to data in 2001, they covered about 3-10% of the average running time of a vessel in straitened waters. Which, of course, hinders the distribution and production of ECDIS.
On the other hand, a number of mapping companies began to intensively issue electronic maps in their own data formats. These non-official maps were named commercial and allowed the industry to begin production of electronic cartographic navigation systems (EX) and chart plotters using commercial electronic maps. The most common commercial electronic cards are cards of S-MAP, Garmin, Navionics and Transas.
The choice of electronic cards.
Often, the question of a user choosing navigation equipment comes down to choosing electronic maps. It is necessary to consider.
Which card format provides the most comprehensive coverage.
Whose technology has the highest level of quality..
Which cards are most often corrected.
Who has the widest network of dealers.
Does the manufacturer have a license for the original cartographic material.
To determine the maps for the area of interest to the user, electronic or paper catalogs of maps are intended. Garmin set a good example, setting up, together with Navikom and Novikart, the issuance of Russian maps for a number of regions. Maps of the company Transas are widely used in navigation cartographic systems and simulators developed by the company. Electronic card formats and programs for displaying them are the intellectual property of development companies, and therefore they are carefully protected.
Using raster maps.
Thanks to the OziExplorer program, raster maps got a second wind. No, raster maps do not load in a traditional navigator. This program supports the exchange of navigation data with navigators and provides the creation of routes and waypoints. All data preparation is carried out on a personal computer, where waypoints are marked on a calibrated and loaded raster map. Then they are entered into the navigator, providing your journey along the intended route. On the other hand, it is possible to independently use an intellectual “bundle” from a computer and a GPS receiver for current navigation on a raster map. The possibilities of such navigation are few, but still inferior to standard navigators..
The development of electronic cards.
When considering electronic cards, it must be borne in mind that their capabilities are provided, on the one hand, by their logical structure, and on the other, by a program for processing and displaying them. The integration of electronic maps with devices and instruments for determining coordinates using the GPS system has led to the appearance of fundamentally new systems, which include GPS navigators and electronic cartographic systems (EX and ECDIS / ECDIS).
Here are some additional features of electronic cards..
Map scale limits from 1: 1000 to 1: 200000000.
High accuracy of data presentation (error within 0.2 mm on a paper map).
Extensive information about map objects, characteristics of navigation equipment, port inputs, tides, currents and climate data.
Activating sound alerts.
Ensuring the visibility of the light sectors.
Wide range of information layers.
Getting proofreading over the Internet.
Based on materials from the book All About GPS Navigators.
Naiman V.S., Samoilov A.E., Ilyin N.R., Sheinis A.I..