Method and system for assisting navigation using rendered terrain imagery

A digital computer system that correlates positional input data for generating a 3-D virtual image, representational of a localized terrain over which a vehicle is traveling, comprising:

• a positional information unit which receives the positional input data provided by a satellite-based positioning system;
• a terrain database unit, containing data of the localized terrain over which the vehicle is traveling;
• and
• an image generation processing unit having a render engine which receives data from the positional information unit and the terrain database unit and which generates the 3-D virtual image representational of the terrain over which the vehicle is traveling, wherein the image generation processing unit generates the 3-D virtual image by referencing a most recent spatial location of the vehicle in the localized terrain over which the vehicle is traveling in order to compute a heading and a pitch of a current position of the vehicle, wherein the most recent spatial location of the vehicle is generated by a location calculation unit which receives the positional input data from the positional information unit.

method for generating a 3-D virtual image representational of a localized terrain over which a vehicle is traveling, comprising the steps of:

• receiving positional input data provided by a satellite-based positioning system which provides latitude data, longitude data, altitude data, and time data to define a spatial location representative of an eye point position seen by an operator of the vehicle in the terrain over which the vehicle is traveling;
• deriving an initial positional reading of the vehicle at time T1 from a sampled GPS data, wherein the initial positional reading at time T1 is represented as A =(X.sub.1, Y.sub.1, Z.sub.1, T.sub.1) where X.sub.1 is representative of latitude at time T.sub.1, Y.sub.1 is representative of longitude at time T.sub.1, and Z.sub.1 is representative of altitude at time T.sub.1;
• deriving a subsequent positional reading of the vehicle at time T2 from the sampled GPS data, wherein the subsequent positional reading at time T2 is represented as B=(X.sub.2, Y.sub.2, Z.sub.2, T.sub.2) where X.sub.2 is representative of latitude at time T2, Y.sub.2 is representative of longitude at time T2, and Z.sub.2 is representative of altitude at time T.sub.2 ;
• calculating a directional vector of the vehicle defined as the vector AB;
• calculating the velocity of the vehicle according to the equation:
• ##EQU4## generating a computer image representative of the eye point position seen by the operator of the vehicle and the directional vector of the vehicle, wherein the computer image is generated by a render engine of an image generation processing unit;
• and
• overlaying the computer image representing the eye point position and the directional vector of the vehicle onto a simulated image of the terrain over which the vehicle is traveling to generate a 3-D virtual image.

A digital computer system that correlates differential positional input data for generating a 3-D virtual image, representational of a localized terrain over which a vehicle is traveling, comprising:

• a positional information unit which receives the differential positional input data provided by a satellite-based positioning system, wherein the differential positional input data is a differential GPS data provided from a Global Positioning Satellite (GPS) unit;
• a terrain database unit, containing data of the localized terrain over which the vehicle is traveling;
• an image generation processing unit having a render engine which receives differential data from the positional information unit and the terrain database unit and which generates the 3-D virtual image representational of the terrain over which the vehicle is traveling;
• and
• a radar information unit that provides radar data to the image generation processing unit, wherein the image generation processing unit incorporates the radar data from the radar information unit with data from the terrain database unit and the positional information unit to generate the 3-D virtual image representative of the terrain over which the vehicle is traveling.