Inertial navigation with gravity deflection compensation
First Claim
1. A navigation system for mounting to a vehicle, the system comprising:
- an inertial sensor for sensing a first navigational parameter of the vehicle and outputting a sensor signal representing the first parameter;
a memory having gravity compensation data for a geographic region; and
a processor coupled to the inertial sensor and the memory, the processor including;
means for accessing a subset of the gravity compensation data, based on position of the vehicle; and
means for deriving a second navigational parameter, based on the sensor signal and the subset of gravity compensation data.
1 Assignment
0 Petitions
Accused Products
Abstract
The novel navigation system, suited for commercial aircraft, includes a sensor for outputting a signal representing a first navigation parameter, a memory having condensed gravity compensation data, and a processor for deriving a second navigational parameter. The processor derives the second navigational parameter from the signal and a subset of the condensed compensation data based on aircraft position. The condensed memory, based on regional gravity deflections, stores sequential gravity compensation values and corresponding navigational coordinates. To conserve memory, adjacent compensation values differ by at least a preset gravity compensation increment. The compensation increment, based on a gravity deflection between 30 and 100 micro-radians, is adequate for commercial aircraft.
36 Citations
27 Claims
-
1. A navigation system for mounting to a vehicle, the system comprising:
-
an inertial sensor for sensing a first navigational parameter of the vehicle and outputting a sensor signal representing the first parameter; a memory having gravity compensation data for a geographic region; and a processor coupled to the inertial sensor and the memory, the processor including; means for accessing a subset of the gravity compensation data, based on position of the vehicle; and means for deriving a second navigational parameter, based on the sensor signal and the subset of gravity compensation data. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15)
-
-
16. A method of condensing gravity compensation data for use in a navigation system having a compensation memory, the method comprising:
-
storing a plurality of sequential gravity compensation values to a first memory, each value having an associated navigational coordinate corresponding to a geographic region; storing a first gravity compensation value of the plurality to a first location of the compensation memory; searching the plurality of values for a nearest different sequential value, the nearest different sequential value differing from the first value by at least a preset gravity compensation increment; and storing the nearest different sequential value to a second location of the compensation memory. - View Dependent Claims (17, 18, 19, 20, 21, 22)
-
-
23. A method of compensating gravity deflection in a navigation system having a sensor for determining a navigational parameter of a vehicle, the method comprising:
-
storing a plurality of sequential gravity compensation values to a compensation memory, each value having an associated navigational coordinate corresponding to a region of earth; accessing a subset of the plurality of gravity compensation values, based on position of the vehicle; and compensating the navigational parameter, based on the subset of gravity compensation data. - View Dependent Claims (24, 25, 26, 27)
-
Specification