Methods for Enhancing the Display of Electronic Nautical Charts with Depths Corrected for Tide

摘要

A collection of related methods are claimed for enhancing the display of electronic nautical charts as viewed within an electronic chart display system by correcting the charted depth values for the effects of tide, and displaying actual depths and derivative graphical information, for a specified date and time. Height clearances are similarly adjusted. This will enable new features within the electronic chart display system that will greatly facilitate navigating coastal waters affected by tide. The method is implemented as a computer program.

主权项

1. A method of updating the display of electronic nautical chart represented in vector format (ENCs) so that depths are available with the correction for tide applied. Existing electronic tide tables or computer program, accessible to the Electronic Chart Display System (ECDS)1 for predicting tide, is referenced given a specific location, date and time, and this tide offset is applied to the depth values to arrive at an updated representation of the coastline and ocean floor for the region.
1 Throughout this document, the use of the term “Electronic Chart Display System” (ECDS), and alternatively “chart-plotter”, shall refer to all electronic display systems used for rendering electronic nautical charts for navigation. There are generally two classes of these devices currently in use: (1) the Electronic Chart System (ECS) used primarily by recreational boaters and some professional mariners; though usually consisting of a dedicated display device, this may also consist of computing devices commonly used aboard such as laptops, tablets or smartphones, running specialized navigation software utilizing electronic charts, and (2) the Electronic Chart Display and Information System (ECDIS) commonly found on larger ships. The claims and subsequent information herein relate equally to both, and refer to both systems collectively as “ECDS” or alternatively as “chart-plotter.”