Complex environment airborne active optical tracking enhancement device

Abstract

The invention relates to the technical field of flight test measurement, in particular to a complex environment airborne active optical tracking enhancement device. Comprising a sphere-like light source prism, a light source generator and a wide-angle connector, the bottom of the sphere-like light source prism is fixedly connected with an aircraft body, and the light source generator is located over the sphere-like light source prism and connected with the top of the sphere-like light source prism through the wide-angle connector. The light source generator is used as an indication light source for the sphere-like light source prism, and is used for guiding the ground photoelectric theodolite to track in real time to obtain flight path information of the sphere-like light source prism. Through the self-luminous photoelectric tracking enhancement device, the image contrast ratio of the optical prism and the surrounding environment is improved, so that the photoelectric tracking distance is increased, and the measurement of seaplane under low visibility is ensured.

Description

Technical Field

[0001] The invention relates to the technical field of flight test measurement, and in particular to an airborne active optical tracking enhancement device in a complex environment. Background Art

[0002] When testing and evaluating the take-off and landing performance of an aircraft, the measurement of the take-off and landing trajectory and attitude of the aircraft is of great significance for evaluating the take-off and landing and handling characteristics of the aircraft. At present, the measurement of the take-off and landing trajectory and attitude of the aircraft is mainly achieved by tracking and measuring the aircraft using ground-based optoelectronic tracking and measurement equipment. This test requires the ground-based optoelectronic tracking and measurement equipment to have all-weather and robust testing capabilities, such as day-and-night tests and test subjects in complex meteorological environments.

[0003] However, the current optoelectronic tracking test process is greatly affected by complex background interference, resulting in problems such as "unclear" targets and "unstable" flight.

[0004] The purpose of the present invention is to propose an airborne active optical tracking enhancement device for complex environments, which solves the problem of reduced photoelectric tracking stability and accuracy caused by water fog, low illumination, low contrast and the like.

[0005] Technical solution of the present invention: In order to achieve the above-mentioned invention objectives, an embodiment of the present invention proposes an airborne active optical tracking enhancement device for complex environments, including a spherical light source prism, a light source generator, and a wide-angle connector; the bottom of the spherical light source prism is fixedly connected to the aircraft body, the light source generator is located directly above the spherical light source prism, and is connected to the top of the spherical light source prism through the wide-angle connector; the light source generator is used to serve as an indicator light source for the spherical light source prism, for guiding the ground optoelectronic theodolite to track in real time, and obtain the flight trajectory information of the spherical light source prism.

[0006] In a possible embodiment, the light source generator includes a light source base, a transparent light source cover, and a light source; the center of the light source base has a hollow hemispherical protrusion, the surface of the hemispherical protrusion is evenly distributed with multiple tangent planes, the top of the hemispherical protrusion also has a tangent plane, and the light source is fixed on each tangent plane; the transparent light source cover is arranged above the light source and is fixedly connected to the light source base. The LED light source can select a visible light source, an infrared light source, etc. according to the sensitive wavelength band of the ground photoelectric theodolite tracking measurement.

[0007] In a possible embodiment, the spherical light source prism includes a hollow hemispherical base, a plurality of corner reflector prisms, and a corner reflector cover plate; the top of the hollow hemispherical base has a cutting plane and is provided with an opening, the opening is used to connect with the wide-angle connector, the surface of the hollow hemispherical base is evenly and alternately provided with multiple layers of cutting plane windows from top to bottom, each cutting plane window has a stepped structure hole, the corner reflector prism is installed in the stepped structure hole, and the corner reflector cover plate is fixed on each cutting plane window.

[0008] In a possible embodiment, the corner reflector is in the shape of a heptahedron, wherein the incident and exit surfaces are arranged parallel to the plane light cutting window.

[0009] Preferably, the corner reflector is composed of three mutually perpendicular reflectors and one incident and output mirror, wherein the incident and output mirror surfaces intersect with the other three mutually perpendicular reflector surfaces, and the cross-section after the intersection is an equilateral triangle, forming a tetrahedron; in order to make the prism fit the stepped structure hole for installation, to ensure the fitting effect between the light window pressing sheet and the mirror surface, and the all-round light receiving effect of the light window incident and output surfaces, the three corners of the tetrahedron prism are cut, so that the equilateral triangle is cut into a regular hexagon, and a heptahedron is generated from the tetrahedron.

[0010] In a possible embodiment, a rubber pad is further included, and the rubber pad matches the stepped structure hole and is disposed in the stepped structure hole. The corner reflector is in sealing and buffering contact with the hollow hemispherical base through the rubber pad.

[0011] In a possible embodiment, the wide-angle connector has a disc flange structure at one end connected to the light source generator, and is fixedly connected to the light source generator by bolts; the wide-angle connector has a circumferential step structure at one end connected to the spherical light source prism, which is inserted into the top opening of the spherical light source prism and fixedly connected by nuts.

[0012] In a possible embodiment, the hollow hemispherical base is made of aviation aluminum alloy material.

[0013] In a possible embodiment, the corner reflection prisms are all made of fused quartz material.

[0014] Beneficial technical effects of the present invention:

[0015] In the amphibious flight test, the high-density water mist and water vapor on the water surface reduced the target contrast. The self-luminous photoelectric tracking enhancement device increased the image contrast between the optical prism and the surrounding environment, thereby increasing the photoelectric tracking distance and ensuring the measurement of seaplanes in low visibility.

[0016] In terms of real-time measurement, the traditional mode cannot accurately track the optical device in real time, so it is necessary to interpret the image coordinates of the aircraft through images after the flight to obtain the aircraft trajectory. The LED light source tracking mode can accurately track the optical device, measure the angle and distance data of the optical device at the same time, directly obtain the trajectory of the aircraft, and realize real-time measurement data output and monitoring.

[0017] In terms of measurement capabilities, the company utilizes independently invented light source generators with LED light source types, such as visible light type and infrared type, to adapt to the visible light tracking and infrared tracking modes of ground photoelectric theodolites, meeting the aircraft tracking and measurement needs in different weather conditions such as clouds and fog, greatly improving the photoelectric tracking and measurement capabilities. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic diagram of an optical tracking enhancement device according to a preferred embodiment of the present invention;

[0019] Figure 2 is a schematic diagram of installing an optical prism according to a preferred embodiment of the present invention;

[0020] Figure 3 is a schematic diagram of cutting the base in a preferred embodiment of the present invention;

[0021] Figure 4 This is a schematic diagram of the installation of a rubber gasket in a preferred embodiment of the present invention;

[0022] Figure 5 It is a schematic diagram of the structure of a rubber gasket in a preferred embodiment of the present invention;

[0023] Figure 6 is a schematic structural diagram of a corner reflection prism according to a preferred embodiment of the present invention;

[0024] Figure 7 Schematic diagram of the light beam reflection principle of the corner reflection prism in the preferred embodiment of the present invention;

[0025] Figure 8 is a schematic diagram of an optical generator according to a preferred embodiment of the present invention;

[0026] Fig. 9 It is a schematic diagram of a light source and a light source base in an optical generator in a preferred embodiment of the present invention;

[0027] Fig.10 is a schematic diagram of the installation of a transformer module in a preferred embodiment of the present invention;

[0028] Fig.11 is a schematic diagram of a wide-angle connector according to a preferred embodiment of the present invention;

[0029] Fig.12 This is a schematic diagram of the installation of a fastening nut according to a preferred embodiment of the present invention;

[0030] Fig.13 is a schematic diagram of the top opening structure of an optical prism in a preferred embodiment of the present invention;

[0031] Fig.14 It is a cross-sectional view of an optical tracking device according to a preferred embodiment of the present invention. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0033] The features and illustrative embodiments of various aspects of the present invention will be described in detail below. In the detailed description below, many specific details are proposed to provide a comprehensive understanding of the present invention. However, it is obvious to those skilled in the art that the present invention can be implemented without the need for some of these specific details. The following description of the embodiments is only to provide a better understanding of the present invention by illustrating examples of the present invention. The present invention is by no means limited to any specific settings and methods proposed below, but covers any improvements, replacements and modifications of structures, methods, devices without departing from the spirit of the present invention. In the accompanying drawings and the following description, known structures and technologies are not shown to avoid unnecessary ambiguity in the present invention.

[0034] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other, and the embodiments can refer to and quote each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0035] like Figure 1 As shown, the light source prism in this example is a hemispherical aviation aluminum alloy 7075 base 100, which ensures strength and reduces weight. The entire light window 200 structure of the base 100 is symmetrically distributed around the circumference. The corner reflector prism is fixed by a pressing plate 300, and the pressing plate 300 is connected to the sphere by M4 screws and fixed by three points. Figure 2 As shown, 20 mounting holes for inlaying corner reflective prisms are evenly arranged on the surface of the base 100, distributed in four layers, with 5 corner reflective prisms 600 in each layer, fixed on the base. The base shell has a diameter of 200 mm. Figure 3 As shown, the bottom surface of the base 100 is cut into a regular pentagonal structure. The joint between the prism and the sphere is sealed with a rubber gasket, such as Figure 4 , Figure 5 shown.

[0036] like Figure 6 As shown, the corner reflection prism 600 is made of fused quartz material and is suitable for lasers with wavelengths of 1.06μm and 1.57μm. The corner reflection prism 600 is a heptahedral cone-shaped total reflection prism consisting of three mutually perpendicular reflection mirrors and one incident (exit) mirror. The prism angle error is no more than 10 seconds, and the surface error is no more than 5 seconds; the prism reflection surface is coated with an internal reflection film, and the projection surface is coated with an anti-reflection film, with a transmittance of ≥95%, and has the ability to resist laser damage.

[0037] like Figure 7 As shown, when a beam of parallel light is incident perpendicular to the large surface, it passes through three right-angle reflection surfaces in sequence and is emitted from the internal reflection surface. The emitted light is parallel to the incident light and in the opposite direction. For example, an incident light beam A passes through the reflective glass surface of the corner reflection prism and is emitted to the reflective surface I, then reflected to the reflective surface II, then reflected to the reflective surface III, and finally reflected by the reflective surface III, and passes through the reflective prism glass surface to emit the reflected light beam A'.

[0038] like Figure 8 As shown, the light source generator 400 of this example includes an LED light source 401, a light source cone base 403, a light source glass cover 402, a glass cover pressing piece 404, and an LED light source voltage conversion module 405. The entire LED light source 401 structure is uniformly encapsulated in an organic transparent light source glass cover 402, and the light source glass cover 402 is a hemisphere with a diameter of 60 mm. The light source glass cover 400 is pressed by a glass cover pressing piece 404 and fastened to the wide-angle connector 500 by 6 screws. Fig. 9 As shown, the LED light sources 401 are distributed in two layers (1+6) on the surface of the light source cone base, and each LED light source is fastened with three M4 screws. The light source cone base is fastened to the wide-angle connector by a height-adjustable bolt. Fig.10 As shown, in order to ensure the use of LED light source, a transformer module is designed to convert the external airborne power supply into the voltage required by the LED. The LED power transformer module 405 is embedded in the inner cavity at the bottom of the light source cone base and fastened with 4 screws. The LED light source 401 can select a visible light source, an infrared light source, etc. according to the sensitive band of the ground photoelectric theodolite tracking measurement.

[0039] The light source of this example uses 11 3W high-brightness LED light sources. The main parameters of the light source are: voltage DC3.2-3.7V; power 3W; working life 50,000 hours; light divergence angle 120°. The onboard power supply DC28V is converted to DC3.2V using an onboard transformer module to match the use conditions of the LED light source. The LED light source has a divergence angle of 120° and an operating temperature of -30° to 70°.

[0040] like Fig.11As shown, the wide-angle connector 500 is used to connect the light source generator and the light source prism. The wide-angle connector 500 has a disc flange structure 501 at one end connected to the light source generator, and is fixedly connected to the light source generator 400 by 6 bolts; Fig.12 The wide-angle connector shown in the figure has a circumferential stepped structure 502 at one end connected to the spherical light source prism, which is inserted into the top opening 101 of the spherical light source prism (such as Fig.13 ) and then fixedly connected by tightening nut 800. Fig.14 As shown, the circumferential step structure 502 is divided into four sections, wherein the first section has two sides of a cylindrical shape cut into a cutting plane for easy removal of the fixture; the table formed at the connection between the second section and the third section fits and clamps the top opening of the optical prism; the fourth section is a thread, and the circumferential step structure of the wide-angle connector is fixed to the top of the light source prism cavity by a fastening nut 800. The circumferential step structure 502 is a hollow tube cavity, which is convenient for routing the power line from the optical prism cavity to the light source generator LED light source.

[0041] In this example, the airborne active optical tracking enhancement device is fixed to the body at 5 points using a flat plate structure, and M6 threaded holes are designed. The vibration meets the requirements of the E curve of the HB-5830 sinusoidal vibration function spectrum.

[0042] The airborne active optical tracking enhancement device in this example requires airborne environmental engineering analysis. A wind pressure load is applied to the side of the light source prism device, and the wind pressure is calculated to be 625KN / m2 based on the aircraft speed of 1000m / s. To simplify the analysis, the threaded holes and parts with details are ignored, the grid is divided, and the equivalent stress distribution diagram is obtained by solution. The wide-angle connector cavity cylindrical structure is made of hardened stainless steel with a yield stress greater than 400MPa. The materials of other parts are aviation hard aluminum alloy (7075) with a yield stress greater than 450MPa. Therefore, the strength is sufficient and no damage will occur.

[0043] This example is a moisture-proof design for the airborne active optical tracking enhancement device. To ensure moisture-proof performance, the device should at least meet the IP54 protection level. In the design, the following measures are adopted:

[0044] (1) It is sealed with an O-shaped silicone rubber sealing ring, and the protection level can reach IP67.

[0045] (2) The aviation plug uses a waterproof aviation plug with a silicone sealing gasket, which is waterproof and moisture-proof.

[0046] The anti-salt spray design of the airborne active optical tracking enhancement device in this example adopts the following measures:

[0047] (1) All connecting screws, nuts and washers are made of 304 stainless steel.

[0048] (2) The interior of the light source prism device is sealed with a silicone rubber gasket, the light source part is sealed with an O-ring, and the light window is made of organic glass with good salt spray corrosion resistance.

[0049] (3) The high-strength aluminum alloy of the light source prism device is shot peened to remove the surface oxide scale and anodized to improve its resistance to salt spray corrosion.

[0050] Photoelectric tracking test method of airborne active optical tracking enhancement device:

[0051] 1. Fix the airborne active optical tracking enhancement device and the matching mounting base to the aircraft body.

[0052] 2. Connect the aircraft power supply to the airborne active optical tracking enhancement device and debug the LED light source to turn on and work.

[0053] 3. Use the ground-based photoelectric theodolite to track and measure the actual flight aircraft. First, use the manual tracking mode to operate the equipment to adjust the aircraft into the field of view; then switch to the LED light source tracking mode for automatic tracking. At the same time, the photoelectric theodolite measures the distance and angle information of the optical tracking enhancement device and outputs the trajectory data of the aircraft in real time.

Claims

1. An active optical tracking enhancement device for complex environments, characterized in that: The invention comprises a spherical light source prism, a light source generator and a wide-angle connector; the bottom of the spherical light source prism is fixedly connected to the aircraft body, the light source generator is located directly above the spherical light source prism and is connected to the top of the spherical light source prism through the wide-angle connector; the light source generator is used as an indicator light source for the spherical light source prism, and is used to guide the ground photoelectric theodolite to track in real time and obtain the flight trajectory information of the spherical light source prism.

2. The complex environment airborne active optical tracking enhancement device according to claim 1, characterized in that: The light source generator includes a light source base, a transparent light source cover, and a light source; the center of the light source base has a hollow hemispherical protrusion, the surface of the hemispherical protrusion is evenly distributed with multiple cutting planes in the circumferential direction, the top of the hemispherical protrusion also has a cutting plane, and the light source is fixed on each cutting plane; the transparent light source cover is arranged above the light source and is fixedly connected to the light source base.

3. The complex environment airborne active optical tracking enhancement device according to claim 1, characterized in that: The spherical light source prism comprises a hollow hemispherical base, a plurality of corner reflector prisms, and a corner reflector cover plate; The top of the hollow hemispherical base has a cutting plane and an opening, and the opening is used to connect with the wide-angle connector. The surface of the hollow hemispherical base is evenly and alternately provided with multiple layers of cutting plane windows from top to bottom, and each cutting plane window has a stepped structure hole. The corner reflection prism is installed in the stepped structure hole, and the corner reflector cover is fixed on each cutting plane window.

4. The complex environment airborne active optical tracking enhancement device according to claim 3, characterized in that: The corner reflector is in the shape of a triangular pyramid tetrahedron, including three mutually perpendicular reflection surfaces and one incident and exit surface, wherein the incident and exit surface is arranged parallel to the cutting plane window.

5. The complex environment airborne active optical tracking enhancement device according to claim 4, characterized in that: Cut the three corners of the tetrahedron prism to cut the equilateral triangle into a regular hexagon, and generate a heptahedron from the tetrahedron.

6. The complex environment airborne active optical tracking enhancement device according to claim 3, characterized in that: It also includes a rubber pad, which matches the stepped structure hole and is arranged in the stepped structure hole. The corner reflection prism is in sealing and buffering contact with the hollow hemispherical base through the rubber pad.

7. The complex environment airborne active optical tracking enhancement device according to claim 1, characterized in that: The end of the wide-angle connector connected to the light source generator has a disc flange structure, which is fixedly connected to the light source generator by bolts; the end of the wide-angle connector connected to the spherical light source prism has a circumferential step structure, which is inserted into the top opening of the spherical light source prism and fixedly connected by nuts.

8. The complex environment airborne active optical tracking enhancement device according to claim 3, characterized in that: The hollow hemispherical base is made of aviation aluminum alloy material.

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