Strapdown inertial navigation system

Abstract

The utility model discloses a strapdown inertial navigation system and belongs to the technical field of inertial navigation. The problems that an existing inertial navigation system is large in size and cannot achieve light weight are solved. The strapdown inertial navigation system comprises a box body, wherein a table body assembly is arranged in the box body; the bottom of the box body is provided with a guard plate and a power panel; the table body assembly comprises a table body frame, and the table body frame is fixed in the box body; three optical fiber gyroscopes are fixed on the outer side of the table body frame, and three accelerometers are mounted in the table body frame; a navigation plate is installed on the top of the table frame, and an IF module is installed on the side face of the table frame. According to the utility model, the table body frame is arranged in the box body, the three accelerometers are arranged in the table body frame, and the three gyroscopes are fixed on the outer side of the table body frame, so that the whole table body assembly is compact in structure, high in space utilization rate, small in size and convenient to carry on various carriers.

Description

Technical Field

[0001] The utility model relates to the technical field of inertial navigation, in particular to a strapdown inertial navigation system. Background Art

[0002] The working principle of inertial navigation is based on Newton's three laws of mechanics. The inertial sensor measures the angular motion and linear motion of the vehicle to calculate the position, speed and attitude information of the vehicle. Inertia, like mass, is an inherent property of all objects. Therefore, the inertial navigation system does not require any external information and does not radiate any information outward. It can autonomously and covertly perform continuous three-dimensional positioning and three-dimensional orientation by relying solely on the inertial sensor itself. It has the advantages of strong autonomy, high concealment, good real-time performance, high short-term accuracy, complete output information, and all-weather operation. It is widely used in the navigation systems of various vehicles such as sea, land, air, space, and ground.

[0003] There are many inertial sensors in the inertial navigation system, usually including three fiber optic gyroscopes and three accelerometers that are orthogonal to each other. Therefore, it is particularly important to optimize the layout of each inertial sensor, improve space utilization, and reduce the size of the inertial navigation system. Common inertial navigation systems in the prior art are large in size and heavy in weight. When installed on a carrier, they take up a lot of space and are not light enough. Utility Model Content

[0004] In view of the deficiencies in the prior art, the utility model provides a strapdown inertial navigation system, which solves the problem that the prior inertial navigation system is large in size and cannot be lightweight.

[0005] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0006] A strapdown inertial navigation system comprises a box body, a platform assembly is arranged inside the box body; a satellite guide plate and a power supply board are installed at the bottom of the box body;

[0007] The platform assembly includes a platform frame, which is fixed inside the box body; three fiber optic gyroscopes are fixed on the outside of the platform frame, and three accelerometers are installed inside the platform frame; a navigation board is installed on the top of the platform frame, and an IF module is installed on the side of the platform frame.

[0008] In this solution, a platform frame is set inside the box body, three accelerometers are installed inside the platform frame, and three gyroscopes are fixed on the outside of the platform frame. The entire platform assembly has a compact structure, high space utilization, and a small size, which is convenient for being mounted on various carriers.

[0009] Furthermore, the three fiber optic gyroscopes are respectively an X-axis fiber optic gyroscope, a Y-axis fiber optic gyroscope and a Z-axis fiber optic gyroscope; the Z-axis fiber optic gyroscope is installed at the bottom of the platform frame, and the X-axis fiber optic gyroscope and the Y-axis fiber optic gyroscope are installed on two adjacent sides of the platform frame; the X-axis fiber optic gyroscope, the Y-axis fiber optic gyroscope and the Z-axis fiber optic gyroscope are mutually orthogonal;

[0010] The three accelerometers are respectively X-axis acceleration, Y-axis acceleration and Z-axis acceleration; the X-axis acceleration, Y-axis acceleration and Z-axis acceleration are all installed on a mounting frame inside the platform frame; the X-axis acceleration, Y-axis acceleration and Z-axis acceleration are orthogonal to each other.

[0011] In this solution, the X-axis fiber optic gyroscope, the Y-axis fiber optic gyroscope, and the Z-axis fiber optic gyroscope are respectively installed on the three surfaces of the platform frame, which not only realizes the orthogonality between the two, but also does not occupy the internal space of the platform frame; and provides installation positions for the X-axis acceleration, Y-axis acceleration, and Z-axis acceleration inside the platform frame.

[0012] Furthermore, two rectangular frames are respectively provided on two adjacent side surfaces of the box body, a first reflector and a second reflector are respectively installed in the two rectangular frames, a first mirror cover is installed on the outer side of the first reflector, and a second mirror cover is installed on the outer side of the second reflector.

[0013] In this solution, a first reflector and a second reflector are installed on two adjacent side surfaces of the box body. By measuring the pitch angle and yaw angle of the normal of the first reflector and the second reflector relative to the horizontal plane, the sensitive axis deviation of the fiber optic gyroscope can be calibrated, which is convenient for subsequent software compensation and improves the calibration accuracy.

[0014] Furthermore, the box body includes a base and a cover plate, and the cover plate is detachably connected to the base; the platform assembly, the sanitary guide plate and the power supply board are all installed inside the base.

[0015] Furthermore, the mounting surfaces of the base and the cover plate are stepped, an annular square groove is provided on the mounting surface of the base, and an O-ring is filled in the annular square groove.

[0016] In this solution, the cover plate is buckled onto the stepped structure of the base to avoid occupying the external space of the base so that the overall shape meets the dimensions; an O-ring is arranged in the annular square groove to improve the sealing between the base and the cover plate.

[0017] Furthermore, two optical cable sockets are arranged on the side of the base, and both optical cable sockets are electrically connected to the sanitary guide plate.

[0018] Furthermore, a radio frequency socket is provided on the side of the base.

[0019] The beneficial effects of the utility model are:

[0020] In the strapdown inertial navigation system provided by the utility model, a platform frame is designed inside the base, and three accelerometers are installed using the internal space of the platform frame, and three fiber optic gyroscopes are installed using the three sides of the platform frame, thereby improving space utilization and reducing the overall volume. The mounting surface at the connection between the base and the cover plate is designed to be a step-type structure, and the cover plate is buckled on the step-type structure to reduce the external space occupied by the base; an annular square groove is provided on the step-type connection surface, and an O-ring is filled inside the annular square groove to ensure the airtightness of the connection between the base and the cover plate. A first reflector and a second reflector are installed on two adjacent vertical surfaces on the outside of the base, which is convenient for external optical calibration of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a schematic diagram of the structure of a strapdown inertial navigation system of the utility model;

[0022] Figure 2 This is an exploded diagram of a strapdown inertial navigation system of the utility model;

[0023] Figure 3 This is a schematic diagram of the structure of the platform assembly in the utility model;

[0024] Figure 4 This is an exploded view of the platform assembly in the utility model;

[0025] Figure 5 This is a schematic diagram of the cross-sectional structure of a strapdown inertial navigation system of the utility model;

[0026] Figure 6 for Figure 5 A partial enlarged view of area A.

[0027] Reference numerals:

[0028] 1. Box body; 11. Base; 111. Optical cable socket; 112. RF socket; 113. O-ring; 12. Cover plate; 2. Platform assembly; 21. Platform frame; 22. Navigation board; 23. IF module; 241. X-axis fiber optic gyroscope; 242. Y-axis fiber optic gyroscope; 243. Z-axis fiber optic gyroscope; 251. X-axis acceleration; 252. Y-axis acceleration; 253. Z-axis acceleration; 254. Mounting frame; 3. Power board; 41. First reflector; 42. First mirror cover; 43. Second reflector; 44. Second mirror cover; 5. Satellite guide plate. DETAILED DESCRIPTION

[0029] The utility model is further described below in conjunction with the accompanying drawings and specific embodiments. The specific implementation of the utility model is described below to facilitate the understanding of the utility model by those skilled in the art, but it should be clear that the utility model is not limited to the scope of the specific implementation. For those of ordinary skill in the art, as long as various changes are within the spirit and scope of the utility model defined and determined by the attached claims, these changes are obvious, and all inventions and creations conceived using the utility model are protected.

[0030] like Figure 1 and Figure 2 As shown, this embodiment provides a strapdown inertial navigation system, which is small in size and light in weight and suitable for being mounted on various types of carriers; it specifically includes:

[0031] Box body 1, table body assembly 2, sanitary guide plate 5 and power supply board 3;

[0032] The box body 1 is provided with a platform assembly 2 inside; and a sanitary guide plate 5 and a power supply board 3 are installed at the bottom of the box body 1 .

[0033] like Figure 3 and Figure 4 As shown, the platform assembly 2 includes a platform frame 21, three fiber optic gyroscopes, three accelerometers, a navigation board 22 and an IF module 23; the platform frame 21 is fixed inside the box body 1; three fiber optic gyroscopes are fixed on the outside of the platform frame 21, and three accelerometers are installed inside the platform frame 21; a navigation board 22 is installed on the top of the platform frame 21, and an IF module 23 is installed on the side of the platform frame 21.

[0034] The three fiber optic gyroscopes are respectively an X-axis fiber optic gyroscope 241, a Y-axis fiber optic gyroscope 242 and a Z-axis fiber optic gyroscope 243; the Z-axis fiber optic gyroscope 243 is installed at the bottom of the platform frame 21, and the X-axis fiber optic gyroscope 241 and the Y-axis fiber optic gyroscope 242 are installed on two adjacent sides of the platform frame 21; the X-axis fiber optic gyroscope 241, the Y-axis fiber optic gyroscope 242 and the Z-axis fiber optic gyroscope 243 are orthogonal to each other.

[0035] The three accelerometers are X-axis acceleration 251, Y-axis acceleration 252 and Z-axis acceleration 253; X-axis acceleration 251, Y-axis acceleration 252 and Z-axis acceleration 253 are all mounted on a mounting frame 254 inside the platform frame 21; X-axis acceleration 251, Y-axis acceleration 252 and Z-axis acceleration 253 are orthogonal to each other.

[0036] Two rectangular frames are respectively provided on two adjacent side surfaces of the box body 1, and a first reflector 41 and a second reflector 43 are respectively installed in the two rectangular frames; by measuring the pitch angle and yaw angle of the normal of the first reflector 41 and the second reflector 43 relative to the horizontal plane, the sensitive axis deviation of the fiber optic gyroscope is calibrated, which is convenient for subsequent software compensation and improves the calibration accuracy; a first mirror cover 42 is installed on the outer side of the first reflector 41, and a second mirror cover 44 is installed on the outer side of the second reflector 43.

[0037] like Figure 5 As shown, the box body 1 includes a base 11 and a cover 12, and the cover 12 is detachably connected to the base 11; the platform assembly 2, the guide plate 5 and the power board 3 are all installed inside the base 11; the first reflector 41 and the second reflector 43 are also arranged on two adjacent sides of the base 11.

[0038] like Figure 6 As shown, the mounting surfaces of the base 11 and the cover plate 12 are stepped, and mounting screw holes are opened on the side; the cover plate 12 is snapped onto the stepped mounting surface of the base 11 and assembled and fixed by countersunk screws; an annular square groove is opened on the mounting surface of the base 11, and the annular square groove is filled with an O-ring 113, which improves the sealing between the base 11 and the cover plate 12.

[0039] Two optical cable sockets 111 are arranged on the side of the base 11, and both optical cable sockets 111 are electrically connected to the sanitary guide plate 5. The optical cable sockets 111 are preferably J599 type sockets.

[0040] A radio frequency socket 112 is also provided on the side of the base 11. The radio frequency socket 112 is preferably a TNC radio frequency socket.

[0041] Those skilled in the art will appreciate that the embodiments herein are intended to help readers understand the principles of the present invention, and should be understood that the protection scope of the present invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific variations and combinations based on the technical inspiration disclosed in the present invention without departing from the essence of the present invention, and these variations and combinations are still within the protection scope of the present invention.

Claims

1. A strapdown inertial navigation system, characterized in that: It comprises a box body (1), wherein a platform assembly (2) is arranged inside the box body (1); a guide plate (5) and a power supply board (3) are installed at the bottom of the box body (1); The platform assembly (2) comprises a platform frame (21), wherein the platform frame (21) is fixed inside the box body (1); three fiber optic gyroscopes are fixed outside the platform frame (21), and three accelerometers are installed inside the platform frame (21); a navigation board (22) is installed on the top of the platform frame (21), and an IF module (23) is installed on the side of the platform frame (21).

2. The strapdown inertial navigation system according to claim 1, characterized in that: The three fiber optic gyroscopes are respectively an X-axis fiber optic gyroscope (241), a Y-axis fiber optic gyroscope (242), and a Z-axis fiber optic gyroscope (243); the Z-axis fiber optic gyroscope (243) is mounted on the bottom of the platform frame (21), and the X-axis fiber optic gyroscope (241) and the Y-axis fiber optic gyroscope (242) are mounted on two adjacent side surfaces of the platform frame (21); the X-axis fiber optic gyroscope (241), the Y-axis fiber optic gyroscope (242), and the Z-axis fiber optic gyroscope (243) are mutually orthogonal in pairs; The three accelerometers are respectively an X-axis acceleration (251), a Y-axis acceleration (252), and a Z-axis acceleration (253); the X-axis acceleration (251), the Y-axis acceleration (252), and the Z-axis acceleration (253) are all mounted on a mounting frame (254) inside the platform frame (21); and the X-axis acceleration (251), the Y-axis acceleration (252), and the Z-axis acceleration (253) are mutually orthogonal.

3. The strapdown inertial navigation system according to claim 1, characterized in that: Two rectangular frames are respectively provided on two adjacent side surfaces of the box body (1), a first reflector (41) and a second reflector (43) are respectively installed in the two rectangular frames, a first mirror cover (42) is installed on the outer side of the first reflector (41), and a second mirror cover (44) is installed on the outer side of the second reflector (43).

4. The strapdown inertial navigation system according to claim 1, characterized in that: The box body (1) comprises a base (11) and a cover plate (12), wherein the cover plate (12) is detachably connected to the base (11); the platform assembly (2), the guide plate (5) and the power supply board (3) are all installed inside the base (11).

5. The strapdown inertial navigation system according to claim 4, characterized in that: The mounting surfaces of the base (11) and the cover plate (12) are stepped, and an annular square groove is provided on the mounting surface of the base (11), wherein an O-type sealing ring (113) is filled in the annular square groove.

6. The strapdown inertial navigation system according to claim 4, characterized in that: Two optical cable sockets (111) are arranged on the side of the base (11), and the two optical cable sockets (111) are electrically connected to the guide plate (5).

7. The strapdown inertial navigation system according to claim 4, characterized in that: A radio frequency socket (112) is also provided on the side of the base (11).

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