초록 ▼

Terminal guidance of vehicles is accomplished by accurately determining true position and speed of the vehicle from terrain contour measurements and updating a dead reckoning navigation system with precision to permit navigation by following a programmed flight path. A narrow beam radar altitude sen

Terminal guidance of vehicles is accomplished by accurately determining true position and speed of the vehicle from terrain contour measurements and updating a dead reckoning navigation system with precision to permit navigation by following a programmed flight path. A narrow beam radar altitude sensor measures vehicle clearance altitudes and a reference altitude sensor measures the vehicle clearance above a reference level. These measurements are input to a digital processor for comparison to stored digital terrain contour reference data. Recursive data matching is performed in the digital processor by a nonlinear Kalman filtering technique to provide vehicle position and vehicle velocity correction signals to a navigation controller that generates steering commands to the vehicle control system. Three vehicle position and three vehicle velocity signals are generated and updated in the nonlinear Kalman filtering technique to give near real-time three dimensional position and velocity information.

대표청구항 ▼

A vehicle navigation system, comprising: terrain sampling means for determining at spaced time intervals the elevation of terrain beneath the vehicle and generating point by point data samples of terrain elevation, a dead reckoning guidance system for providing vehicle position and velocity signals,

A vehicle navigation system, comprising: terrain sampling means for determining at spaced time intervals the elevation of terrain beneath the vehicle and generating point by point data samples of terrain elevation, a dead reckoning guidance system for providing vehicle position and velocity signals, data storage means containing prerecorded point by point terrain data, a computational processor responsive to the point by point samples of terrain elevation, vehicle position and velocity signals, and prerecorded point by point terrain data to generate a current predictive position signal and combine the current predictive position signal with a previously generated and stored updated position signal into a new updated position signal for providing discrete signal samples of vehicle velocity correction and vehicle position correction, and a navigation controller responsive to the signal samples from said computational processor to generate vehicle navigation signals.