RU2330792C1 - Aircraft approach landing acs - Google Patents

Abstract

FIELD: transportation.

SUBSTANCE: ACS system incorporates a glide-path receiver, the first adder, the second adder and the terminator connected in series. Also, connected in series are the first differentiating component with its input connected to the glide-path receiver output and the first filter with its output connected to the first adder second input. Connected in series are a pitching angle pick up, the second differentiating component and the second filter with its output connected to the second adder second input. Connected in series are also the third adder with its first input connected to the pitching angle pickup output, while the second input is connected to the pitching angle speedup signal generator, the isodromic filter, the forth adder, the first scale unit and the fifth adder. Connected in series are the pitching angular speed pickup, the second scale unit and the sixth adder with its second input coupled with the elevator in response to the automatic equalising signal and its input connected to the fifth adder second input. Also, connected in series are the seventh adder, the third scale unit, the second terminator and integrating component. The seventh adder input is connected to the first terminator output, while the integrating unit output is connected to the second inputs of the forth and seventh adders.

EFFECT: higher noise immunity and higher accuracy of automatic approach landing.

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Description

The claimed invention relates to the field of automatic control of an airplane, in particular to control systems providing an automatic approach mode.

Known systems for automatic control of an airplane at approach. Such systems are described, in particular, in the copyright certificates SU 762327, B64C 13/18, publ. from 2005.10.10; SU 957519, B64C 13/18, publ. from 2005.10.10; SU 1012524, B64C 13/18, publ. from 2005.09.27, and in the book of Fedorov S.M., Kane V.M., Mikhailova O.I., Sukhikh N.N. Automated flight control. - M .: Transport, 1992, p.107-108.

The disadvantages of the known automatic control systems that provide an automatic approach mode for an aircraft should include the fact that they underestimate the accuracy of the approach due to poor noise immunity.

Closest to the technical nature of the claimed system is a system of automatic control of the approach, presented in the book Fedorov S.M., Kane V.M., Mikhailova O.I., Sukhikh N.N. Automated flight control. - M.: Transport, 1992, p.107-108.

This system comprises series-connected glide path radio receiver, a first adder, a second adder and a limiter; connected in series are the first differentiating element, the input of which is connected to the output of the glide path radio receiver, and the first filter, the output of which is connected to the second input of the first adder. The system also contains a series-connected pitch angle sensor, a second differentiating element and a second filter, the output of which is connected to the second input of the second adder; a third adder connected in series, the first input of which is connected to the output of the pitch angle sensor, and the second input is connected to the pitch angle pick-up switch, isodromic filter, fourth adder, first scale unit and fifth adder; a series-connected pitch angular velocity sensor, a second large-scale unit and a sixth adder, the second input of which is connected to the elevator by an automatic balancing signal, and the output is connected to the second input of the fifth adder. In addition, the system contains a third filter, the input of which is connected to the output by a limiter, and the output is connected to the second input of the fourth adder.

The disadvantage of this automatic control system is that it does not provide a sufficiently high accuracy of the aircraft landing approach due to poor noise immunity. In particular, the signal coming from the glide path radio receiver contains both high-frequency interference and interference with a frequency of 0.5 to 1 Hz, which coincides with the operating frequency range of the aircraft. Moreover, the level of interference often in some cases significantly exceeds the useful signal. In addition, there is a short-term disappearance or jump in the signal of the glide path radio receiver. At the same time, it is not possible to filter the interference by a linear filter and provide the required quality of approach. To filter the interference, the time constant should be Tε _g ≥1 s, and to ensure the required quality of approach, Tε _g <0.2 s. Taking into account the use in the control law of the derivative of the glide path radio signal, the interference filtering problem is fundamental when developing an automatic airplane control system in the approach mode.

The aim of the invention is to increase the accuracy of the approach of the aircraft by improving the noise immunity of the automatic control system.

This goal is achieved due to the fact that in the automatic control system of the aircraft during approach, containing sequentially connected glide path radio, the first adder, the second adder and limiter; the first differentiating element, the input of which is connected to the output of the glide path radio receiver, and the first filter, the output of which is connected to the second input of the first adder in series; connected in series with the pitch angle sensor, a second differentiating element and a second filter, the output of which is connected to the second input of the second adder; a third adder connected in series, the first input of which is connected to the output of the pitch angle sensor, and the second input is connected to the pitch angle pick-up switch, isodromic filter, fourth adder, first scale unit and fifth adder; a series-connected pitch angular velocity sensor, a second scale block and a sixth adder, the second input of which is connected to the elevator by an automatic balancing signal, and the output is connected to the second input of the fifth adder, a seventh adder, a third scale block, a second limiter and an integrator are additionally introduced the device, and the input of the seventh adder is connected to the output of the first limiter, and the output of the integrating device is connected to the second inputs of the fourth and seventh engine diagnostics.

The invention is illustrated in the drawing, which shows a block diagram of the proposed system for automatic control of the aircraft during approach.

This system contains a series-connected glide path radio 1, a first adder 2, a second adder 3, a first limiter 4; the first differentiating element 5 and the first filter 6 are connected in series. The system also includes the pitch angle sensor 7, the second differentiating element 8 and the second filter 9; connected in series with a third adder 10, an isodromic filter 11, a fourth adder 12, a first scale unit 13 and a fifth adder 14; a series-connected pitch angle angular velocity sensor 15, a second scale unit 16 and a sixth adder 17. In addition, the system includes a seventh adder 18, a third scale unit 19, a third scale unit 20, a second stop 20 and an integrator 21 connected in series.

The signal ε _g from the glide path radio receiver 1 is fed to the first input of the adder 2 and through a differentiating device 5 and a filter 6 that filters the high-frequency component of the signal of the derivative of the glide path radio receiver - to the second input of the adder 2.

The signal from the output of the adder 2 is fed to the first input of the adder 3, the second input of which receives the signal υ from the pitch angle sensor 7, passed through the differentiating element 8 and filter 9. The total signal from the output of the adder 3 through the limiter 4, the limit value of which is selected from the conditions flight safety, is fed to the first input of the adder 18. To significantly reduce the effect of interference and malfunctions in the signal of the glide path radio receiver 1 on the quality of the automatic approach, the signal from the output of the adder 18 through the scale unit 19 and the limiter 20 is fed to the input of the integrating device 21, the output signal of which is fed to the second inputs of the adders 12 and 18.

Note that for small values of the output signal of the limiter 4, such that the signal from the limiter 20 is smaller in magnitude than the limit value, a signal is generated at the output of the integrating device 21 as a signal from the limiter 4, passed through a filter with a small time constant. Moreover, the time constant of this filter is defined as the reciprocal of the gain of the scale unit 19. With an increase in the output signal of the limiter 4, the signal at the output of the limiter 20 takes limit values and a signal is generated at the output of the integrating device 21 as a signal from the limiter 4 with increasing delay as well. Thus, the larger the signal at the output of the limiter 4, the higher the filtering level of this signal.

The signal from the output of the pitch angle sensor 7 through the adder 10 and the isodromic filter 11, eliminating the influence of the initial pitch angle on the aircraft approach, is fed to the first input of the adder 12. In this case, the second input of the adder 10 from the encoder forcing the pitch angle signal (not shown shown) give a signal proportional to the slope of the glide path, to increase the speed of access to the glide path. The signal from the output of the adder 12 through the scale unit 13 is fed to the adder 14, the second input of which receives a signal from the pitch angle sensor 15, passed through the scale unit 16 and the adder 17. A signal for the elevator balancing value is received at the second input of the adder 17. Under the influence of a control signal generated at the output of the adder 14 and fed to the elevator drive, the aircraft automatically approaches for landing.

As the results of modeling the SAU-140 system for the AN-140 aircraft showed, when using the proposed automatic control system, due to the improvement of its noise immunity, the accuracy of the aircraft landing approach increased.

Due to non-linear filtering of the control signal, the noise level in the system is reduced by 7 times. If the signal ε _g disappeared at a distance of 2 km and a height of 100 m for a time of 0.4 s, the height error in the known system was 7 m, and in the proposed system it was 1 m. Thus, the proposed system is feasible and applicable, in particular, for aircraft type AN-140.

Claims (1)

Aircraft approach control system containing a glide path radio receiver, a first adder, a second adder and a limiter, a first differentiating element in series, the input of which is connected to the output of a glide path radio receiver, and a first filter, the output of which is connected to the second input of the first adder, connected in series with the pitch angle sensor, the second differentiating element and the second filter, the output of which is connected to the second input of the second adder connected in series to a third adder, the first input of which is connected to the output of the pitch angle sensor, and the second input is connected to the master of the pitch angle boost signal, an isodrome filter, a fourth adder, a first scale unit and a fifth adder configured to generate a control signal for the elevator connected in series to the pitch angular velocity sensor, a second scale unit and a sixth adder, the second input of which is connected to the elevator by an automatic balancing signal, and the output connected to the second input of the fifth adder, characterized in that the seventh adder, the third scale unit, the second limiter and the integrating device are additionally introduced into it in series, the first input of the seventh adder being connected to the output of the first limiter, and the output of the integrating device connected to the second inputs of the fourth and the seventh adders.