A displacement detection device and a working method thereof

Abstract

The present invention relates to a displacement offset detection device and a working method thereof, belonging to the technical field of optical strain gauges, comprising: an optical strain gauge, a light source and an avalanche photodiode, wherein the optical strain gauge is connected to a spherical photoelectric pod; the light source is fixedly connected to a mounting plate, and the light source emits a full-spectrum light to the optical strain gauge; the avalanche photodiode is fixedly connected to the mounting plate, and the avalanche photodiode identifies light of a predetermined spectrum reflected at a predetermined angle by the optical strain gauge; the device can solve the technical problem in the prior art that it is difficult to effectively detect the self-displacement offset of the photoelectric pod in a strong magnetic field environment by using laser scanning equipment.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical strain gauges, and in particular relates to a displacement offset detection device and a working method thereof. Background Art

[0002] The spherical optoelectronic pod is a high-tech device that integrates optical, electronic and mechanical technologies. It is usually carried on a flying platform, a land mobile platform or a fixed building platform to collect image data of the target.

[0003] When the spherical optoelectronic pod rotates and shifts, the displacement will cause the pod's field of view to change. Some targets that were originally in the field of view may move out of the field of view, while some areas that were not originally in the field of view may enter the field of view, which will affect the comprehensive observation of the target and the integrity of data collection. At the same time, because the spherical optoelectronic pod is equipped with ranging equipment such as laser rangefinders, the displacement will cause the emission direction and receiving path of the laser beam to change, thereby affecting the accuracy of ranging. Ranging errors can lead to misjudgment of the target distance, which in turn affects the positioning and trajectory prediction of the target.

[0004] Therefore, timely identification of the rotational displacement offset of the spherical optoelectronic pod is a technical problem that needs to be solved by those skilled in the art.

[0005] The existing patent with publication number CN118583055A discloses a method and device for detecting rail displacement offset. A target ball is arranged on a displacement observation pile, and a plane target is arranged on the rail section around the target ball. The method includes obtaining the respective position information of the monitoring point of the plane target and the central reference point of the target ball at the first time and the second time; determining the displacement deviation of the monitoring point of the plane target according to the respective position information of the monitoring point of the plane target and the central reference point of the target ball at the first time and the second time; and determining the offset of the rail displacement based on the displacement deviation.

[0006] The prior art has the following problems:

[0007] Laser scanning equipment is used to obtain the position change of the target ball. However, when in a strong magnetic field interference environment, for laser scanning equipment based on the time of flight principle (ToF), strong electromagnetic interference will affect the accuracy of the timing circuit, resulting in timing deviations, making the final measured distance data erroneous. For laser scanning equipment based on the triangulation principle, electromagnetic interference will interfere with the angle measurement sensor, causing errors in angle measurement, thereby affecting the accuracy of the three-dimensional coordinate calculation, causing deviations in the collected point cloud data. Therefore, existing laser scanning equipment is difficult to effectively detect the self-displacement offset of the optoelectronic pod in a strong magnetic field environment. Summary of the invention

[0008] The present invention provides a displacement offset detection device and a working method thereof, which can solve the technical problem in the prior art that it is difficult to effectively detect the displacement offset of an optoelectronic pod in a strong magnetic field environment by using laser scanning equipment.

[0009] In order to achieve the above object, the present invention is implemented by the following technical solutions:

[0010] The present application provides a displacement offset detection device, which includes an optical strain gauge, a light source and an avalanche photodiode. The optical strain gauge is connected to a spherical photoelectric pod; the light source is fixedly connected to a mounting plate, and the light source emits a full-spectrum of light to the optical strain gauge; the avalanche photodiode is fixedly connected to the mounting plate, and the avalanche photodiode identifies light that reflects a predetermined spectrum at a predetermined angle through the optical strain gauge.

[0011] Through the above technical solution, the displacement of the optical strain gauge is used to identify the change in the light reflection spectrum, thereby avoiding the interference of strong magnetic fields and improving the anti-interference ability of displacement offset detection.

[0012] In the present invention, the optical strain gauge is a photonic crystal lens, which allows vertical light to pass through and reflects oblique light.

[0013] Through the above technical scheme, a photonic crystal lens is used, based on the bandgap effect and microcavity resonance effect of the photonic crystal, to reflect different spectra when the photonic crystal is in a specific position state, thereby obtaining the motion state of the spherical optoelectronic pod and improving the anti-interference effect.

[0014] In the present invention, the displacement offset detection device further comprises a first lens, a second lens and a sliding frame, wherein the first lens is connected to the photonic crystal lens; the second lens is connected to the spherical optoelectronic pod, and the second lens is arranged parallel to the first lens; the sliding frame is connected to the spherical optoelectronic pod, the sliding frame is slidably connected to the spherical shell, and the first lens is connected inside the sliding frame;

[0015] The spherical optoelectronic pod collects the image of the outer side of the spherical shell through the second lens, the photonic crystal lens and the first lens in sequence.

[0016] Through the above technical solution, the first lens and the second lens are arranged in parallel and the sliding frame is used to make the first lens and the second lens move synchronously, thereby avoiding the interference of the photonic crystal lens on the laser measurement of the spherical optoelectronic pod.

[0017] In the present invention, the number of the above-mentioned light sources is two, and the two light sources are respectively arranged on both sides of the spherical optoelectronic pod, the number of the avalanche photodiodes is two, and the connection line of the two avalanche photodiodes is perpendicular to the connection line of the two light sources.

[0018] Through the above technical solution, a method of arranging the connection line of two avalanche photodiodes and the connection line of two light sources perpendicular to each other is adopted, and a minimum number of light sources and avalanche photodiodes is used to achieve all-round detection.

[0019] In the present invention, the above-mentioned displacement offset detection device also includes an optical fiber, a laser transmitter, a laser receiver and a wireless communication module. The optical fiber vertically penetrates the vertical section of the spherical shell; the laser transmitter is connected to one end of the optical fiber; the laser receiver is connected to the end of the optical fiber away from the laser transmitter; and the wireless communication module is connected between the laser transmitter and the laser receiver.

[0020] Through the above technical solution, the photoelastic effect of optical fiber is used to identify the stress changes in the vertical section of the spherical shell, and then the rotational motion resistance of the spherical shell is obtained, thereby improving the identification of the displacement deviation tendency.

[0021] The present application also provides a working method of a displacement offset detection device, which uses the above-mentioned displacement offset detection device and also includes the following steps:

[0022] Step S1: When the spherical optoelectronic pod rotates, the light source irradiates the photonic crystal lens through the gap between the first lens and the second lens;

[0023] Step S2: When the photonic crystal lens is at a specific angle, the light reflecting a specific spectrum is received by the avalanche photodiode, and the position of the photonic crystal lens relative to the mounting plate is determined based on the information of the received spectrum, thereby determining whether there is a displacement offset.

[0024] Through the above technical solution, the displacement offset is detected by identifying the change of the reflection spectrum, which avoids the interference of the strong electromagnetic environment on the device and improves the stability of the displacement offset detection.

[0025] In the present invention, the above step S2 further includes:

[0026] Step S3: Based on the photoelastic effect of the optical fiber, the stress change of the spherical shell is identified, and then it is determined whether the spherical shell has movement resistance.

[0027] Through the above technical solution, the movement resistance of the spherical shell is identified to prevent the displacement offset caused by movement obstruction, thereby improving the accuracy of the displacement offset detection of the spherical optoelectronic pod. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 An axonometric diagram of a displacement offset detection device and a spherical optoelectronic pod after assembly provided by an embodiment of the present invention;

[0030] Figure 2 A front view of a displacement detection device and a spherical optoelectronic pod after assembly provided by an embodiment of the present invention;

[0031] Figure 3 for Figure 2 Sectional view at AA in the figure;

[0032] Figure 4 A side view of a displacement detection device and a spherical optoelectronic pod after assembly provided by an embodiment of the present invention;

[0033] Figure 5 for Figure 4 The cross-sectional view at BB in FIG.

[0034] Figure 6 for Figure 5 A local enlarged view of point C in FIG.

[0035] Figure 7 An exploded diagram of a displacement detection device and a spherical optoelectronic pod provided in an embodiment of the present invention;

[0036] Figure 8 A schematic diagram of the connection between the moving part and the sliding frame of the spherical optoelectronic pod provided in an embodiment of the present invention;

[0037] Fig. 9 for Figure 3 A partial enlarged view of point D in the figure.

[0038] Icons: 1-first lens; 101-sliding frame; 102-telescopic cover; 103-optical strain gauge; 104-bracket; 2-second lens; 3-light source; 4-avalanche photodiode; 5-spherical optoelectronic pod; 6-spherical shell; 7-optical fiber; 701-laser transmitter; 702-wireless communication module; 703-laser receiver; 8-mounting plate; 801-slide groove. DETAILED DESCRIPTION

[0039] The embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0040] In the description of the present application, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0041] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, unless otherwise specified, "plurality" means two or more.

[0042] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be welding, bolt connection, or riveting; it can be fixed connection, detachable connection, or integral connection; it can be mechanical connection or electrical connection; it can be directly connected or indirectly connected through an intermediate medium, or it can be internal communication between two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0043] Example:

[0044] Please refer to Figures 1 to 9 , Figures 1 to 9 An embodiment of the present application is shown.

[0045] This embodiment provides a displacement offset detection device, such as Figures 1 to 5 As shown, it includes an optical strain gauge, a light source 3 and an avalanche photodiode 4. The optical strain gauge 103 is connected to the spherical photoelectric pod 5 through a bracket 104, and the optical strain gauge moves with the movement of the spherical photoelectric pod 5; the light source 3 is fixedly connected to the mounting plate, and the light source 3 emits a full spectrum of light to the optical strain gauge; the avalanche photodiode 4 is fixedly connected to the mounting plate, and the avalanche photodiode 4 recognizes light of a predetermined spectrum reflected at a predetermined angle by the optical strain gauge.

[0046] When in use, the mounting plate 8 is connected to the mounting platform of a carrier or a fixed building, such as Figure 5As shown, the slide groove 801 is fixedly connected to the bottom of the mounting plate 8 by screws, the spherical shell 6 has a groove, and a roller is arranged in the groove. The spherical shell 6 is composed of two halves, which are fastened at both ends and then slidably connected in the groove by rollers. The avalanche photodiode 4 and the light source 3 are both fixedly connected to the bottom of the slide groove 801, and their positions relative to the carrier or the mounting platform are relatively fixed. The spherical optoelectronic pod 5 is independently connected to the driving device. The spherical optoelectronic pod 5 and its driving device belong to the prior art and are not within the protection scope of this application.

[0047] It should be noted that the avalanche photodiode 4 operates under high reverse bias and has an internal gain mechanism that can multiply the photocurrent. Its response characteristics to light of different wavelengths are different from those of ordinary photodiodes, and to a certain extent, the changes in the spectrum can be indirectly reflected by detecting the changes in the photocurrent and the gain characteristics.

[0048] Through the above technical solution, the displacement of the optical strain gauge is used to identify the change in the light reflection spectrum, thereby avoiding the interference of strong magnetic fields and improving the anti-interference ability of displacement offset detection.

[0049] As a preferred implementation, the optical strain gauge is a photonic crystal lens, which allows vertical light to pass through and reflects oblique light.

[0050] Photonic crystals have a periodic refractive index distribution, which forms a photonic bandgap, preventing the propagation of light waves of a specific frequency. When the lens position changes, causing the refractive index or structure of the photonic crystal lens to change, the position and width of the bandgap will change. The lens position can be sensed by detecting the change in the bandgap. For example, the most intuitive application of photonic crystals in nature is that animal feathers have different luster when viewed from different angles.

[0051] Through the above technical solution, a photonic crystal lens is used, based on the bandgap effect and microcavity resonance effect of the photonic crystal, to reflect different spectra when the photonic crystal is in a specific position state, thereby obtaining the motion state of the spherical optoelectronic pod 5 and improving the anti-interference effect.

[0052] As a preferred implementation method, Figure 3 , Figure 5 , Figure 7 as well as Figure 8 As shown, the displacement offset detection device further includes a first lens 1, a second lens 2 and a sliding frame 101, the first lens 1 is connected to the photonic crystal lens; the second lens 2 is connected to the spherical optoelectronic pod 5, and the second lens 2 is arranged parallel to the first lens 1; the sliding frame 101 is connected to the spherical optoelectronic pod 5, the sliding frame 101 is slidably connected to the spherical shell 6, and the first lens 1 is connected inside the sliding frame 101;

[0053] The spherical optoelectronic pod 5 collects the image of the outer side of the spherical shell 6 after passing through the second lens 2, the photonic crystal lens and the first lens 1 in sequence.

[0054] When using, Figure 3 and Figure 5 As shown, the sliding frame 101 rotates with the spherical photoelectric pod 5, and slides at the opening of the spherical shell 6 by means of step sliding friction. At the same time, the telescopic cover 102 extends at one end and shortens at the other end as the sliding frame 101 moves, so as to prevent foreign objects from entering the opening of the spherical shell 6. It should be noted that the specific structure of the telescopic cover 102 can refer to the dust cover of the machine tool spindle. The sliding frame 101 rotates with the spherical photoelectric pod 5 in two directions, one of which is as shown in FIG. Figure 3 As shown, the spherical optoelectronic pod 5 swings left and right, and the other is to rotate with the axis of the spherical optoelectronic pod 5. When swinging, the sliding frame 101 slides at the opening, and when rotating along the axis, the sliding frame 101 drives the spherical shell 6 to rotate. That is, the spherical optoelectronic pod 5 is independently driven, and the sliding frame 101 is connected to the spherical optoelectronic pod 5 and moves with it. When the sliding frame 101 swings left and right, it is slidably connected to the spherical shell 6. When the sliding frame 101 rotates along the axial direction of the spherical optoelectronic pod 5, it drives the spherical shell 6 to slide on the mounting plate 8.

[0055] Through the above technical solution, the first lens 1 and the second lens 2 are arranged in parallel and the sliding frame 101 is used to make the first lens 1 and the second lens 2 move synchronously, thereby avoiding the interference of the photonic crystal lens on the laser measurement of the spherical optoelectronic pod 5.

[0056] As a preferred implementation, there are two light sources 3 , which are respectively arranged on both sides of the spherical optoelectronic pod 5 , and there are two avalanche photodiodes 4 , and the line connecting the two avalanche photodiodes 4 is perpendicular to the line connecting the two light sources 3 .

[0057] Through the above technical solution, the connection line of the two avalanche photodiodes 4 and the connection line of the two light sources 3 are arranged perpendicular to each other, and the minimum number of light sources 3 and avalanche photodiodes 4 is used to achieve all-round detection.

[0058] As a preferred implementation method, Figure 5 and Figure 6 As shown, the above-mentioned displacement offset detection device also includes an optical fiber 7, a laser transmitter 701, a laser receiver 703 and a wireless communication module 702. The optical fiber 7 is vertically connected to the vertical section of the spherical shell 6; the laser transmitter 701 is connected to one end of the optical fiber 7; the laser receiver 703 is connected to the end of the optical fiber 7 away from the laser transmitter 701; and the wireless communication module 702 is connected between the laser transmitter 701 and the laser receiver 703.

[0059] Through the above technical solution, the photoelastic effect of the optical fiber 7 is used to identify the stress change of the vertical section of the spherical shell 6, and then the rotational movement resistance of the spherical shell 6 is obtained, thereby improving the identification of the displacement deviation tendency.

[0060] This embodiment also provides a working method of the displacement offset detection device, which uses the above-mentioned displacement offset detection device and also includes the following steps:

[0061] Step S1: When the spherical optoelectronic pod 5 rotates, the light source 3 irradiates the photonic crystal lens through the gap between the first lens 1 and the second lens 2;

[0062] Step S2: When the photonic crystal lens is at a specific angle, the light reflecting a specific spectrum is received by the avalanche photodiode 4. Based on the information of the received spectrum, the position of the photonic crystal lens relative to the mounting plate is determined, and then whether there is a displacement offset is determined.

[0063] Through the above technical solution, the displacement offset is detected by identifying the change of the reflection spectrum, which avoids the interference of the strong electromagnetic environment on the device and improves the stability of the displacement offset detection.

[0064] As a preferred implementation, the above step S2 further includes:

[0065] Step S3: Based on the photoelastic effect of the optical fiber 7, the stress change of the spherical shell 6 is identified, and then it is determined whether the spherical shell 6 has movement resistance.

[0066] Through the above technical solution, the movement resistance of the spherical shell 6 is identified to prevent the displacement offset caused by movement obstruction, thereby improving the accuracy of the displacement offset detection of the spherical optoelectronic pod.

[0067] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope of the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A displacement offset detection device, characterized in that: include: An optical strain gauge (103) is connected to the spherical photoelectric pod (5), and the optical strain gauge (103) moves along with the movement of the spherical photoelectric pod (5); A light source (3) is fixedly connected to the bottom of the mounting plate (8), wherein the light source (3) emits full-spectrum light to the optical strain gauge (103); an avalanche photodiode (4) fixedly connected to the bottom of the mounting plate (8), the avalanche photodiode (4) identifying light of a predetermined spectrum reflected at a predetermined angle by the optical strain gauge (103); The optical strain gauge (103) is a photonic crystal lens, which allows vertical light to pass through and reflects oblique light. The photonic crystal lens reflects different spectra when the photonic crystal is in a specific position state based on the bandgap effect and microcavity resonance effect of the photonic crystal, thereby obtaining the motion state of the spherical optoelectronic pod (5); A sliding frame (101) is connected to a bracket (104), one end of the bracket (104) away from the sliding frame (101) is connected to the spherical optoelectronic pod (5), the sliding frame (101) is slidably connected to a spherical shell (6), and the spherical shell (6) is rotatably connected to the bottom of the mounting plate (8); The first lens (1) is connected inside the sliding frame (101), and the photonic crystal lens is connected to a side of the first lens (1) facing the spherical optoelectronic pod (5).

2. The displacement detection device according to claim 1, characterized in that: Also includes: A second lens (2) connected to the outside of the spherical optoelectronic pod (5), the second lens (2) being arranged parallel to the first lens (1); The spherical optoelectronic pod (5) collects an image of the outer side of the spherical shell (6) after passing through the second lens (2), the photonic crystal lens and the first lens (1) in sequence.

3. The displacement detection device according to claim 2, characterized in that: The number of the light sources (3) is two, and the two light sources (3) are respectively arranged on both sides of the spherical photoelectric pod (5). The number of the avalanche photodiodes (4) is two, and the connection line of the two avalanche photodiodes (4) and the connection line of the two light sources (3) are perpendicular to each other.

4. The displacement detection device according to claim 3, characterized in that: Also includes: An optical fiber (7) vertically penetrates the vertical section of the spherical shell (6); A laser transmitter (701) connected to one end of the optical fiber (7); A laser receiver (703) connected to an end of the optical fiber (7) facing away from the laser transmitter (701); A wireless communication module (702) is connected between the laser transmitter (701) and the laser receiver (703).

5. A working method of a displacement offset detection device, characterized in that: Using the displacement offset detection device as claimed in claim 4, further comprising the following steps: Step S1: when the spherical optoelectronic pod (5) rotates, the light source (3) irradiates the photonic crystal lens through the gap between the first lens (1) and the second lens (2); Step S2: When the photonic crystal lens is at a specific angle, the light reflecting a specific spectrum is received by the avalanche photodiode, and the position of the photonic crystal lens relative to the mounting plate (8) is determined based on the information of the received spectrum, thereby determining whether there is a displacement offset.

6. The working method of the displacement offset detection device according to claim 5, characterized in that: After step S2, the following steps are also included: Step S3: Based on the photoelastic effect of the optical fiber, the stress change of the spherical shell (6) is identified, and then it is determined whether the spherical shell (6) has movement resistance.

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