Patent ID: 6469664
Filing Date: 2002-10-22
Classification: B63B,B63G,G01C,G08G,Y10S

Abstract:
An apparatus for alerting the user of a surface marine vessel of proximity to terrain, said apparatus comprising:an input for receiving signals representative of a position, speed, and a track of the surface marine vessel, and coupled to a data base of stored terrain information; an output; and a signal processing device coupled to said input and said output, for defining a look ahead distance as a function of the speed of the surface marine vessel; defining a first alert envelope indicative of a first level of terrain proximity alert, wherein boundaries of the first alert envelope are determined as a first function of the track, look ahead distance, and a terrain floor boundary; defining a second alert envelope indicative of a second level of terrain proximity alert, wherein boundaries of the second alert envelope are determined as a second function of the track, look ahead distance, and the terrain floor boundary; and outputting an alert signal when a subset of the stored terrain information is located within the boundaries of at least one of the first and second alert envelopes.