Carl Lee Schaefer

US Patent:

59012722, May 4, 1999

Filed:

Oct 24, 1996

Appl. No.:

8/736176

Inventors:

Carl G. Schaefer - Woodbridge VA
Kelly M. McCool - University Park MD
David J. Haas - North Potomac MD

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

G06F 1518

US Classification:

395 22

Abstract:

The invention is directed to means, utilizing a neural network, for estimating helicopter airspeed at speeds below about 50 knots using only fixed system parameters as inputs to the neural network. The system includes: means for entering at least one initial parameter; means for measuring, in a nonrotating reference frame associated with the helicopter, a plurality of variable state parameters generated during flight of the helicopter; means for determining a plurality of input parameters based on the at least one initial parameter and the plurality of variable state parameters and for generating successive signals representing the input parameters; at least one equation representing a nonlinear input-output relationship between the input parameters and airspeed; memory means for storing the at least one equation and for successively receiving and storing signals from the determining means; and processing means responsive to signals received from the memory means for generating airspeed information based on the input parameters and the at least one equation.

US Patent:

57516090, May 12, 1998

Filed:

Oct 24, 1996

Appl. No.:

8/740067

Inventors:

Carl G. Schaefer - Woodbridge VA
Kelly M. McCool - University Park MD
David J. Haas - North Potomac MD

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

G01C 2110

US Classification:

364565

Abstract:

The invention is directed to a method, utilizing a neural network, for estimating helicopter airspeed in the low airspeed flight range of below about 50 knots using only fixed system parameters as inputs to the neural network. The method includes the steps of: (a) defining input parameters derivable from variable state parameters generated during flight of the helicopter and measurable in a nonrotating reference frame associated with the helicopter; (b) determining the input parameters and a corresponding helicopter airspeed at a plurality of flight conditions representing a predetermined low airspeed flight domain of the helicopter; (c) establishing a learned relationship between the determined input parameters and the corresponding helicopter airspeed wherein the relationship is represented by at least one nonlinear equation; (d) storing the at least one nonlinear equation in a memory onboard the helicopter; (e) measuring real time values of the variable state parameters during low airspeed flight of the helicopter; (f) calculating real time values of the input parameters; (g) storing the real time values of the input parameters in the memory; (h) processing the real time values of the input parameters in accordance with the at least one nonlinear equation to determine real time airspeed; and (i) displaying the real time airspeed.

US Patent:

58901019, Mar 30, 1999

Filed:

Oct 22, 1997

Appl. No.:

8/955970

Inventors:

Carl G. Schaefer - Woodbridge VA
Kelly M. McCool - University Park MD
David J. Haas - North Potomac MD

Assignee:

The United States of America as represented by the Secretary of the Navy - Washington DC

International Classification:

G01C 2110

US Classification:

702144

Abstract:

The invention is directed to a system, utilizing a neural network, for estimating helicopter airspeed in the low airspeed flight range of below about 50 knots using only fixed system parameters as inputs to the neural network. The method includes the steps of: (a) defining input parameters derivable from variable state parameters generated during flight of the helicopter and measurable in a nonrotating reference frame associated with the helicopter; (b) determining the input parameters and a corresponding helicopter airspeed at a plurality of flight conditions representing a predetermined low airspeed flight domain of the helicopter; (c) establishing a learned relationship between the determined input parameters and the corresponding helicopter airspeed wherein the relationship is represented by at least one nonlinear equation; (d) storing the at least one nonlinear equation in a memory onboard the helicopter; (e) measuring real time values of the variable state parameters during low airspeed flight of the helicopter; (f) calculating real time values of the input parameters; (g) storing the real time values of the input parameters in the memory; (h) processing the real time values of the input parameters in accordance with the at least one nonlinear equation to determine real time airspeed; and (i) displaying the real time airspeed.