Radar anti-collision system for ships in waters adjacent land areas

• US 3,890,616 A
• Filed: 09/06/1973
• Issued: 06/17/1975
• Est. Priority Date: 12/28/1972
• Status: Expired due to Term

• Current Assignee: Kenta Kabayama, Masabumi Iizuka, Shizuhiro Izawa, Takeshima Kojima
• Original Assignee: Kenta Kabayama, Masabumi Iizuka, Shizuhiro Izawa, Takeshima Kojima
• Inventors: Kabayama, Kenta, Kojima, Takeshima, Iizuka, Masabumi, Izawa, Shizuhiro
• Primary Examiner(s): Wilbur, Maynard R.
• Assistant Examiner(s): Montone, G. E.
• Application Number:
  US05/394,575
• Time in Patent Office: 649 Days
• Field of Search: 343/5MM,5ST,5EM,5LS,6TV,112CA,5DP
• US Class Current: 342/41
• CPC Class Codes: G01S 13/937 of marine craft

Abstract

The radar signals of a vessel navigating on a given course are supplied to a data processing unit connected to an input of a computer. An auxiliary memory is connected to an input of the computer and has stored therein data with respect to land areas adjacent the course of the vessel, and these data are supplied to the computer progressively in accordance with a preset program for comparison with the data supplied by the processing unit. If the comparison indicates that the vessel is at a greater distance from land areas than limits defined by the stored positional data, the processed positional data corresponding to scanned land areas is deleted from the data supplied to a collision avoidance program, so that the processing by this collision avoidance program is made more reliable. After processing by these programs, data are displayed on a display unit.

Claims

1. A radar anti-collision system, for avoiding collisions between water-borne vessels in waters adjacent land areas, comprising, in combination, a radar mounted on a vessel and scanning objects in the course of the vessel;

a data processing unit having an input connected to said radar and processing the positional data of land areas and of other vessels scanned by said radar;

a computer connected to the output of said data processing unit;

an auxiliary memory connected to an input of said computer and having stored therein a set of marine positional data with respect to land areas adjacent the course of the vessel, said auxiliary memory supplying the stored data to said computer in accordance with a present program for comparison, in said computer, with the positional data supplied by said data processing unit from said radar; and

a general display unit connected to the output of said computer;

said computer comparing the stored positional data with the processed positional data and, responsive to such comparison indicating that the vessel is at a greater distance from land areas than limits defined by the stored positional data, cancelling processed positional data relating to land areas from the positional data to a collision avoidance progRam in said computer so that the processing by said collision avoidance program becomes more reliable and the data displayed on said general display unit, responsive to such comparison indicating that the vessel is at a greater distance from land areas than limits defined by the stored positional data, does not include any positional data relating to land areas.

2. A radar anti-collision system, as claimed in claim 1, in which the stored positional data with respect to land areas adjacent the course of the vessel are represented by linear segments extending generally parallel to coastlines rather than by accurately contoured coastlines.

3. A radar anti-collision system, as claimed in claim 2, in which the positional data is represented with respect to a pair of rectangular coordinates X and Y whose origin O is on the vessel carrying the anti-collision system;

the coordinates X representing the position of the vessel along its course and the coordinates Y representing the distance of the course from such linear segments.

4. A method of avoiding collisions between water-borne vessels in waters adjacent land areas utilizing a radar mounted on a vessel travelling a course in such waters, said method comprising operating the radar to scan the course of the vessel and provide positional data with respect to land areas and other vessels in the neighborhood of the vessel carrying the radar;

processing the positional data at the output of the radar;

supplying the processed positional data to a computer;

storing positional data related to land areas adjacent the course of the vessel;

supplying such stored data to the computer in accordance with a preset program;

utilizing the computer to compare the stored positional data with the processed positional data;

utilizing such comparison to delete, from the processed positional data, positional data with respect to land areas when the vessel is at a distance from such land areas at least equal to a predetermined minimum distance; and

supplying the remaining positional data to a collision avoidance program.