RU2234440C1 - Landing optical system - Google Patents

Abstract

FIELD: aviation; airfield equipment.

SUBSTANCE: proposed optical landing system includes indicator lamps showing position of flying vehicle on glide path, lenses, whose main optical axis is directed along preset angle of glide path; lenses are combined with photo-electric converter connected with amplifying converter equipped with logic unit containing square signal generator. Flying vehicle position lights include pair of lights showing position of flying vehicle above glide path and pair of lights showing position of flying vehicle below glide path; they are located at edge of runway symmetrically relative to its axis. Optical device is made in form of collimator with photometer optically connected with it. Digital photo-electric converter is provided with camera tube (vidicon). Amplifying converter is provided with AC symmetrical triangular sweep voltage generator, reversible pulse counter whose first input is connected with square pulse generator and second and third inputs are connected with outputs of two logic circuits; each logic circuit is connected to first and second outputs of AC triangular sweep voltage generator and electronic amplifier whose input is connected to output of vidicon target. Output of counter is connected to electrical circuit of photo-electrical converter consisting of switch, comparator and analog-to-digital converter; photometer is connected to second input of comparator. Outputs of switch are connected with each pair of lights showing position of flying vehicle on glide path. Pair of lights showing position of flying vehicle below glide path and pair of lights showing position of flying vehicle above glide path are provided with red and yellow light filters.

EFFECT: enhanced reception of visual information by pilot under poor weather conditions.

3 cl, 3 dwg

Description

The invention relates to the field of aviation, in particular to aerodrome equipment, and can be used in light-signal equipment of an airfield to increase its information content to increase the safety of landing aircraft (LA) in conditions of limited visibility.

The aerodrome lighting system for providing aircraft landings according to ICAO categories II and III is known (see Basov Yu.G. Lighting devices. M., Transport, 1993, p. 216), which contains axial line lights, restrictive, side, input runway (runway) lights, end-safety-zone lights, approach zone lights. Landing call lights are placed on the first 900 m of the runway in the form of rows of three lights, perpendicular and symmetrical with respect to the axis of the runway. Such a system is quite complex and cumbersome and at the same time does not give the pilot complete visual information about the flight altitude due to the fact that on most modern aircraft, a significant part of the landing zone lights is not visible to the pilot due to the limited view at the landing landing angles. At this difficult stage of landing, piloting an aircraft is carried out by the pilot manually and visually. He needs visual information about the position of the aircraft relative to the runway in direction, height and speed of descent. But this light-signaling system does not have sufficient information content and does not provide the necessary landing safety, especially in difficult weather conditions. Operational deployment of lighting equipment to unequipped airfields with such lighting equipment is impossible.

A known method and installation for the directional orientation of an aircraft during an approach by Britec, France, is taken as a prototype (see US patent No. 5136288, class B 64 P 1/18, 1992). A device that includes the installation of at least three lights on each side of the runway at its entrance edge, made in such a way that during their work they create a start of the light zone in the direction of the aircraft approaching, allowing it to occupy the correct position. However, this system only solves the problem of ensuring the correct approach with good visibility and does not provide sufficient safety for the aircraft landing at its final stage. The system does not provide operational deployment of lighting equipment at unequipped airfields.

The known "glide path display system", containing two landing indicator lights of the aircraft position lights on the glide path, located on the runway, an optical device - lenses that convert light from the aircraft landing light into a linear image. In this case, the main optical axis of the lenses is directed along the given glide path angle to the side headlight of an approaching aircraft. The system comprises a photovoltaic converter made with a photodiode array, a logic device, an amplification-conversion device, a rectangular pulse generator. A logic device connected to the matrix determines the position of the aircraft relative to a given glide path by comparing the position of the linear image with the reference position. According to the results of the comparison, the indicators - two lamps placed on the runway - provide blinking, steady glow, showing the pilot the position of the aircraft relative to the glide path (see US patent L 4554943, MKI 340-948, 86). However, the disadvantage of this system is that this placement of indicator lamps does not give the pilot complete visual information about the position of the aircraft relative to the runway, and the tact of the system is the lack of accuracy in detecting the following of angular values along the glide path of the aircraft

SUMMARY OF THE INVENTION

The objective of the invention is to create a light-signal system of the airfield, which allows the pilot to obtain visual information about the position of the aircraft relative to the runway at the final stage of landing - alignment and landing. The system should provide ease of perception by the pilot of visual information in difficult weather conditions. The system should ensure the rapid deployment of lighting equipment at unequipped airfields, i.e. should provide a higher degree of safety landing aircraft.

In accordance with the invention, the task is achieved in that in an optical landing system (OSB), including indicator lamps for position lights of the aircraft on the glide path, approach lights, restriction lights, side lights, runway center line lights, an optical device — lenses directed by their optical main axis along the given glide path angle to the aircraft headlight, photoelectric converter, an amplification-conversion device connected to it with a logic unit, a rectangular pulse generator, in In accordance with the invention, the lights of the position of the aircraft on the glide path are made in the form of a pair of lights "position of the aircraft above the glide path" installed further than the touchdown point of the aircraft, and pairs of lights "position of the aircraft below the glide path" installed closer to the touch point of the aircraft and are located symmetrically relative to its axis. In addition, the optical device is made in the form of a collimator with a photometer optically connected to it, and a digital photoelectric converter (PEC) is made with a television transmitting tube (vidicon). Moreover, the amplifier-converting device is made with a generator of variable symmetrical triangular sweep voltage, a reversible pulse counter, the first input of which is connected to a rectangular pulse generator, the second and third inputs are connected to the outputs of two logic circuits, each of which is connected respectively to the first and second outputs the alternating triangular voltage generator of the sweep and the electronic amplifier, the input of which is connected to the target output of the vidicon, the counter is connected to its output FEP to an electric circuit consisting of serially connected switch, a comparator, an analog-digital converter, wherein the illuminance is connected to the second input of the comparator, outputs a switch associated with each pair of lamps LA position on the glidepath.

A pair of lights "position of the aircraft below the glide path" and a pair of lights "position of the aircraft above the glide path" are made with red and yellow filters, respectively.

The invention is illustrated by drawings.

Figure 1 shows a diagram of the runway lighting equipment in accordance with the task.

Figure 2 shows the plot of the voltage at the control points of the photoelectronic Converter.

Figure 3 shows a schematic view of the location of the runway lights when leveling the aircraft.

Figure 1 shows:

1 - photoelectric converter (PEC);

2 - amplifier-converting device;

3 - lens;

4 - television transmitting tube-vidicon;

5 - target;

6 - translucent mirror;

7 - a mirror;

8 - deflecting system;

9 - sweep generator;

10 - scheme "And";

11 - electronic amplifier;

12 - reverse counter;

13 - pulse generator;

14 - digital-to-analog converter;

15 - a comparator;

16 - switch - contactor circuit;

17 - two passing lights;

18 - two distant lights;

19 - light filter;

20 - aircraft headlight;

21 - photometer;

22 - approach lights;

23 - restriction lights;

24 - centerline lights.

Information confirming the possibility of carrying out the invention

OSB, including approach lights 22, restriction lights 23, runway center line lights 24, contains a digital photomultiplier 1 connected to a photometer 21, ADC 14 connected in series, comparator 15, switch - contactor circuit 16, aircraft position lights on glide path 17, 18, located at the edges of the runway symmetrically about the axis. To indicate the landing point of the aircraft, a pair of distant lights from it was introduced “the position YES above the glide path” 18 and a pair of passing lights — below the glide path 17 — with yellow and red filters. FEP 1 contains sequentially located optical elements 19, 6, 3, 7 of an optical device, a television transmission tube - Vidicon 4, an amplifying-converting device 2, an alternating symmetric triangular voltage generator for scanning 9 and rectangular control pulses 13, and a reversing device in the amplifying-converting device a pulse counter 12, the control inputs of which are connected through logic circuits 10 to the outputs of the generator 9 and amplifier 11. The input of amplifier 11 is connected to the target output of the vidicon.

The system is equipped with restrictive lights 23 with a red filter located along the end of the runway and designed to indicate its end. The airdrome is equipped with additional light-signaling equipment - lights 17, 18 of the landing zone of 2 rows of lights installed on each side of the runway outside and along it in the initial part; the distance from the start of the runway to the start of the landing zone lights is up to 150 m.

The system operates as follows.

The device - a photoelectric converter (PEC) with a digital output is designed to convert the movements of a luminous point object - the offset of the autocollimation flare of the LA-20 headlight in the focal plane of the autocollimator into a digital code proportional to this movement. FEP 1 contains a transmitting television tube, such as a vidicon. The image of the luminous object is projected onto the target 5 of the vidicon, the potential relief of which is switched by an electron beam. A signal arises in the circuit of the signal plate of the tube, which is formed at the moment the image beam intersects. The time interval between the start of the sweep and the signal pulse is proportional to the amount of movement. An electronic circuit converts this time interval into a digital code. The accuracy of the device is achieved by applying a superpositional measurement method, in which a periodic linearly mixed reciprocating motion of the electron beam is superimposed on the measured image displacement and the time difference between pairs of adjacent pulses generated in the signal circuit of the tube during the sweep is calculated. In this case, the sensitivity of the device in the measured value increases. To do this, the scan generator 9 generates a linearly varying voltage of a triangular shape to control the electron beam and rectangular pulses that control the operation of the electronic circuit.

Figure 2 shows the voltage diagrams at the control points A, B, C, D of the circuit, respectively. Diagram G also shows the time sweep of the electron beam, i.e. displacement of the electron spot relative to the position of the main optical axis of the autocollimator lens on the target of the vidicon.

Lens 3 creates a parallel stream of light from the headlamp 2 of the aircraft, the Vidicon 4 television tube is placed in such a way that its target 5 is in the focal plane of the lens 3. The light stream of the headlight 20 through a translucent mirror 6 and lens 3 is optically connected to the mirror 7, which it is in turn connected with the target of the vidicon. The deflecting system 8 is connected to the sweep generator 9, which generates a linear (triangular) voltage A. The control outputs of the generator 9 are connected to the inputs of two coincidence logic circuits (of type “I”) 10, the second inputs of which are connected through the amplifier 11 to the signal electrode of the target 5. The amplifier 11 amplifies the photocurrent pulses that occur when the electron beam commutes the target image 20 on the target, and the "I" circuits separate the pulses B from the output of the amplifier 11 into two channels according to the signals of the generator 9. The outputs of the "I" circuits are connected to the inputs of the reverse pulse counter 12 and control the mode of operation, providing the summation or subtraction of counting pulses of high frequency from the pulse generator 13, the output of which is connected to the counting input of the counter.

, где Т - период развертки. Реверсивный счетчик вычисляет число, пропорциональное разности Δt=t₁-t₂, которая в этой случае равна нулю. Если изображение цели - фары 20 - смещается относительно нулевого положения величину l_р, изменяется соотношение отрезков t₁ и t₂. При прямо ходе электронного пучка импульс с фототока с мишени, возникающий в момент пересечения пучком изображения цели - фары 20, проходя через управляющий вход реверсивного счетчика 12, приводит его в режим суммирования, который продолжается до поступления следующего импульса фототока при обратном движении электронного пучка. В момент поступления этого импульса счетчик переводится в режим вычитания. Таким образов система позволяет летчику получить визуальную информацию о положении самолета относительно точки приземления по дальности и высоте относительно ВПП на заключительном этапе посадки - выравнивания и приземления. Система обеспечивает легкость восприятия летчиком визуальной информации в сложных метеоусловиях.The luminous flux of the headlamp LA 20, passing through the filter 19, reflected from the translucent mirror 6, enters the photometer 21 to adjust the brightness of the light of the approaching LA. Then it passes through the lens 3 to the mirror 7, the rotation angle of which is adjusted to the angle of the glide path of the aircraft planning and is reflected from it back into the lens 3, which projects the target image through the translucent mirror 6 onto the target 5 of the vidicon. Each value of the mismatch angle between the axis of sight and normal to the mirror 7 corresponds to a certain constant offset l _{p of the} image of the headlight on the target. In the absence of a mismatch (l _p = 0), the position of the aircraft flare on the target coincides with the axis of symmetry of the electron beam motion (the main optical axis of the lens 1), therefore, for the forward and reverse electron beam paths, one electric pulse B comes from the target of the vidicon. Time intervals between pulses are the same and numerically equal to half the period (figure 2), i.e. t ₁ = t ₂ =

where T is the sweep period. The reversible counter calculates a number proportional to the difference Δt = t ₁ -t ₂ , which in this case is zero. If the image of the target - headlights 20 - is shifted relative to the zero position by the value of l _p , the ratio of the segments t ₁ and t ₂ changes. In the direct course of the electron beam, the pulse from the photocurrent from the target, which occurs when the beam intersects the image of the target - headlights 20, passing through the control input of the reversible counter 12, brings it into the summation mode, which continues until the next pulse of the photocurrent arrives when the electron beam moves backward. At the moment this pulse arrives, the counter is put into subtraction mode. With such images, the system allows the pilot to obtain visual information about the position of the aircraft relative to the touchdown point in range and height relative to the runway at the final stage of landing — leveling and landing. The system provides ease of perception by the pilot of visual information in difficult weather conditions.

Claims (3)

1. An optical landing system containing indicator lamps for the lights of the position of the aircraft on the glide path, an optical device (lenses) directed by its optical main axis along a given angle of the glide path, a photoelectric converter (PEC) combined with it, an amplification-converting device connected to it with a logic unit including a rectangular pulse generator, characterized in that the position lights of the aircraft on the glide path are made in the form of a pair of lights “the position of the aircraft above the glide path” installed further than the landing point of the aircraft, and pa lights “position of the aircraft below the glide path”, installed closer to the landing point of the aircraft, and located at the edges of the runway symmetrically about its axis, the optical device is made in the form of a collimator with a photometer optically connected to it, the digital photoelectric converter is made with a television transmitting tube (vidicon). 2. The optical landing system according to claim 1, characterized in that the amplifier-converter device is made with a generator of variable symmetrical triangular sweep voltage, a reversible pulse counter, the first input of which is connected to a rectangular pulse generator, the second and third inputs are connected to the outputs of two logic circuits , each of which is connected, respectively, to the first and second outputs of the alternating triangular voltage generator sweep and an electronic amplifier, the input of which is connected to the output ode to the target of the vidicon, the counter is connected by its output to the PEC electric circuit, consisting of a series-connected switch, a comparator, an analog-to-digital converter, the photometer being connected to the second input of the comparator, the switch outputs are connected to each pair of aircraft position lights on the glide path. 3. The optical landing system according to claim 1, characterized in that a pair of lights “position of the aircraft below the glide path” and a pair of lights “position of the aircraft above the glide path” are made with red and yellow filters, respectively.

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