Boots – shoes – and leggings
Patent
1980-01-15
1983-03-15
Ruggiero, Joseph F.
Boots, shoes, and leggings
73179, G01P 362, G06G 778, G08B 2100
Patent
active
043769802
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention concerns an improved variometer, of a type similar to the one shown in U.S. Ser. No. 113,829 the disclosure of which is incorporated by reference herein.
2. Discussion of the Prior Art
One recalls that the variometer according to the abovementioned application or principal patent comprises essentially a dial including in a standard way a scale representative of a vertical speed, a needle indicating on the said scale the instantaneous vertical speed of the aircraft, an indicator representative of the potential vertical speed, which is moveable around the dial and whose position in relation to the needle indicates instantaneously the acceleration on the trajectory of the aircraft, and can also include an indication by a digital display of the gradient of the airplane.
In such a variometer, the signal representative of the instantaneous vertical speed is obtained by means of a calculation member producing the equation ##EQU2## equation in which hx.degree. is the signal of the instantaneous vertical speed of the aircraft; anemometric unit; provided by an inertial guidance unit.
Moreover, the signal representative of the potential vertical speed h.degree..sub.T of the aircraft is obtained in carrying out by means of a calculation member of an equation in the form: ##EQU3## formula in which hx.degree. is the instantaneous vertical speed of the aircraft;
By reason of the nature of the parameters which it utilizes, and in particular of the ground speed V.sub.x and of the component J.sub.z of the acceleration, the variometer according to the principal patent applies esentially to aircraft equipped with an inertial guidance unit.
SUMMARY OF THE INVENTION
The invention has, therefore, more particularly for its object a variometer whose general principal is similar to thart of the above-mentioned application, but is able to utilize the parameters available on the aircraft not having any inertial guidance units.
In order to achieve this result, according to the invention, the value of the instantaneous vertical speed indicated by the needle of the variometer is obtained by incorporating to the filtered vertical speed, a lead phase which is the function of the acceleration following the vertical axis of the airplane J.sub.z.sbsb.1, calculated from the vertical accelerartion measured according to the axis connected to the aircraft and of the angle of rolling .phi. of the aircraft.
The expression of this instantaneous vertical speed is therefore in the form: ##EQU4## formula in which: j.sub.z.sbsb.1 is the component of the acceleration on the vertical axis connected to the plane; speed h.degree..sub.T of the aircraft is furnished from the following formula: ##EQU5## in which: I: hx.degree. is the instantaneous vertical speed of the aircraft (which is obtained as previously indicated); ##EQU6## the expression TAS designating the True Air Speed of the aircraft; .tau.'.sub.1 and .tau.'.sub.2 being constants of time; axis of the aircraft; the aircraft and of the longitudinal accelerartion compensated for gravity, the expression dVx/dt being of the form: ##EQU7## in which .tau..sub.3 is a time constant.
An important advantage in the method of determination of the potential vertical speed previously described, consists in that it allows one to obtain, in case of a wind gradient a true readout whatever the airspeed of the aircraft may be, and this, without it being necessary to effect other corrections, as that was the case in the variometer according to the principal patent.
BRIEF DESCRIPTION OF THE DRAWINGS
One embodiment of the invention will be described hereafter, as a non-limiting example, with reference to the accompanying drawings in which:
FIG. 1 is a block diagram of the system for calculating the instantaneous vertical speed of the aircraft;
FIG. 2 is a block diagram of the system for calculating the potential vertical speed h.degree..sub.T of the aircraft;
FIG. 3 is a diagrammatic illustration making it possible to illustrate the princ
REFERENCES:
patent: 3196691 (1965-07-01), Escobosa
patent: 3264876 (1966-08-01), Bosch et al.
patent: 3296422 (1967-01-01), Rusler, Jr.
patent: 3964307 (1976-06-01), Huhne
Chin Gary
Ruggiero Joseph F.
S.F.E.N.A.
LandOfFree
Variometer does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Variometer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Variometer will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1660260