Method for estimating wind
AssigneeLockheed Martin Corporation
InventorCharles R. Campbell
Life of this patent
Estimating the term…
Abstract
Attitude, ground velocity, and acceleration inputs from an aircraft Inertial Navigation System (INS) and/or a Global Positioning System (GPS) instrument on board the aircraft, are used to estimate wind velocity relative to the aircraft and/or the ground in three dimensions. A wind velocity in the third dimension is assumed to be zero. In an exemplary embodiment, one or more of a) atmospheric density, b) speed of sound, C) air temperature, d) thrust of the aircraft, e) aerodynamic force coefficients of the aircraft, and f) mass of the aircraft, are used in conjunction with the inputs from the INS/GPS instrument(s) to estimate the wind velocity. Air temperature can be used, for example, together with an ambient air pressure and/or a known altitude of the aircraft to indicate an atmospheric density.
Claims28
A method for estimating, at a first object in a fluid, a velocity of the fluid relative to a second object, comprising:
- determining an acceleration of the first object relative to the second object;
- determining a dynamic pressure of the fluid on the first object;
- determining a thrust vector of the first object relative to the second object;
- and
- estimating the velocity of the fluid relative to the second object in three dimensions, based on the determined acceleration, the determined dynamic pressure, the determined thrust vector and an assumption that a speed of the fluid along a single dimension and relative to the second object is zero.
A method for estimating air velocity of a vehicle, comprising:
- determining a parameter associated with the vehicle;
- and
- determining a weighting factor to weight force equations and a velocity equation in an equation set, based on the determined parameter;
- and
- solving the weighted equation set to estimate the air velocity of the vehicle.
A method for estimating, at a first object in a fluid, a velocity of the fluid relative to a second object, comprising:
- estimating the velocity of the fluid relative to the second object in three dimensions, based on a determined acceleration of the first object relative to the second object, a determined dynamic pressure of the fluid on the first object, a determined thrust vector of the first object relative to the second object, and an assumption that a speed of the fluid along a single dimension and relative to the second object is zero.
Dependencies are inferred from the claim text.