Digital Nautical Charts
SAIC has developed a digital capability for both continuous maintenance and vector product updates (VDU) to provide current nautical data updates to a digital nautical charts database. A digital nautical chart is a vector-based digital product designed to support marine navigation and other GIS applications by portraying selected maritime features in a format suitable for computerized marine navigation.
We Provide Critical, Up-to-Data GIS Navigation Data
Many GIS applications have critical information currency requirements. Meeting these requirements has been difficult, particularly when end-users are geographically dispersed, with widely varying communication capabilities and capacities. GIS databases can be very large and transmitting full databases is often impractical, especially when end-users have limited bandwidth available. SAIC's GIS database update technology is designed to solve this problem.
Unlike paper charts, the digital nautical chart must be updated digitally, which requires the transmission of new data containing all of the updates in a form that is simple for users to ingest and apply to their databases. Continuous maintenance for digital nautical chart regions is updated on a weekly basis to keep the data current. Continuous maintenance involves new collection of data on charts, updates marine safety information and a list of navigational aids along inland waterways and coasts, and cleans and validates digital nautical chart databases. These updates are critical for navigation safety. The problem then entails that the required change data can be voluminous and sending a full digital nautical chart replacement can require several hours to transmit to low bandwidth vessels, making it operationally prohibitive.
We Provide Solutions to Time-Critical Problems
To solve this time-critical problem, SAIC developed a digital nautical chart update capability based on a file patching technology. This technology is widely used in industry to update applications over the Web, creating a new version of the software from an older version. This technique greatly reduces the volume of data required to transmit the changes.
By applying this technology to GIS databases, SAIC can reduce update data volumes by up to a factor of 100. The training required for the end-user is minimal and the generation and application of the updates can be fully automated. Moreover, the inherent checks in the SAIC software are designed to make misapplication of the updates virtually impossible, helping to ensure that the updated data is error-free. This increases navigation safety for mariners, through eliminating errors of omission or commission of the past in manually updating paper charts.
The first significant application of this technology is SAIC's Digital Nautical Chart, but it is extensible to any vector GIS database. Therefore, SAIC can provide an all-inclusive production capability, including collecting, updating, and cleaning the database; and can disseminate vector-based patches as necessary to remote sites and users, or in this case, to mariners.
