US 5,072,396 A · Navigation systems

Abstract

An aircraft navigation system has a digital map store of terrain features or man-made features in the region over which the aircraft is flying. Infra-red television cameras view the surrounding of the aircraft. Their outputs are supplied to processors in which the camera outputs are compared with a library of features transformed according to the camera viewing angle. Information about those features identified is supplied to a correlator which correlates the features against the map store to identify their location in the map and estimates the aircraft position as an output to a navigation computer. The system also indicates aircraft attitude which may be independent of known-features, from observation of the horizon. Position information can also be provided by dead reckoning from a known initial position by monitoring the change in positional relationship of a feature from the initial position to that at a later position.

Claims14

Dependent claims

A vehicle navigation system comprising:

a passive imaging sensor, said sensor being mounted to view the surroundings of the vehicle and to provide an output in accordance therewith;
an image library of the image characteristics and nature of a plurality of different features;
means for comparing the output of said sensor with said image library to identify the presence and nature of features within the field-of-view of the sensor and to provide output signals representative of the nature of identified features;
a digital map store of the region in which the vehicle is moving, the map store containing information as to the location and nature of individual features in the region;
and means for correlating said output signals with said map store to identify the position of the vehicle from the relative location of the identified features in the field of view of the sensor with respect to the location of said features in the region as determined by said map store and to provide a position output in accordance therewith.

2 more elements

Dependencies are inferred from the claim text.

Navigation systems

Life of this patent

Navigation systems

Life of this patent

Abstract

Claims14