An inertial navigation calibration fixture

Abstract

This utility model discloses an inertial navigation system (INS) calibration fixture, which includes a base, a rotating mechanism, and two fine-tuning mechanisms. The rotating mechanism includes two shaft systems, a first frame, and a second frame. The central axis of the first shaft system extends vertically, and its lower end is connected to the base and can rotate relative to the base around its own central axis. Its upper end is connected to the first frame. The central axis of the second shaft system extends horizontally, and one end is connected to the first frame and can rotate relative to the first frame around its own central axis. Its other end is connected to the second frame, which is used to mount the INS. The two fine-tuning mechanisms are detachably connected to the two shaft systems one-to-one and are used to drive the shaft systems to rotate slightly. The beneficial effects of this utility model are: this INS calibration fixture can realize multi-attitude and multi-angle calibration of the INS with high calibration accuracy.

Description

Technical Field

[0001] This utility model relates to the field of inertial navigation calibration technology, and in particular to an inertial navigation calibration fixture. Background Technology

[0002] An inertial navigation system (INS) is an autonomous navigation system that does not rely on external information or radiate energy to the outside. Its operating environment includes not only the air and ground, but also underwater. The basic working principle of INS is based on Newton's laws of motion. By measuring the acceleration of the carrier in an inertial reference frame, integrating it over time, and transforming it into the navigation coordinate system, information such as velocity, yaw angle, and position in the navigation coordinate system can be obtained. Therefore, the accuracy and stability of INS product parameters are crucial. To accurately measure the various parameters of the inertial instruments in INS products, parameter calibration methods are generally used. These methods employ multi-position rate and position calibration, and through a specific error model, the error parameters contained in the instrument output signal are calculated; these are the instrument accuracy and performance parameters.

[0003] Existing inertial navigation calibration fixtures (such as the calibration fixture for inertial navigation products disclosed in application number 201920714147.5) require the calibration fixture to be fixedly installed on a turntable before calibrating the inertial navigation system. The inertial navigation system is then detachably fixed onto the calibration fixture. During calibration, the inertial navigation system can be manually rotated to complete the calibration of all six sides. However, this type of calibration fixture can only complete the calibration of the six sides of the inertial navigation system and cannot achieve multi-attitude and multi-angle calibration of the inertial navigation system, resulting in poor calibration accuracy. Utility Model Content

[0004] The purpose of this invention is to overcome the above-mentioned technical deficiencies and propose an inertial navigation calibration fixture to solve the technical problem that the existing calibration fixtures cannot achieve multi-attitude and multi-angle calibration of inertial navigation and have poor calibration accuracy.

[0005] To achieve the above technical objectives, the present invention provides an inertial navigation calibration fixture, comprising:

[0006] Base;

[0007] A rotating mechanism includes two shaft systems, a first frame, and a second frame. The central axis of the first shaft system extends vertically and its lower end is connected to the base and can rotate relative to the base about its own central axis. Its upper end is connected to the first frame. The central axis of the second shaft system extends horizontally and its one end is connected to the first frame and can rotate relative to the first frame about its own central axis. Its other end is connected to the second frame. The second frame is used to mount an inertial navigation system.

[0008] Two fine-tuning mechanisms are detachably connected to the two shaft systems, one-to-one, for driving the shaft systems to rotate slightly.

[0009] Furthermore, the shaft system includes an outer ring, a middle ring, and an inner ring, which are coaxially arranged. One end of the middle ring is located inside the outer ring and rotatably connected to it, while the other end of the middle ring is located outside the outer ring. One end of the inner ring is located inside the middle ring and rotatably connected to it, while the other end of the inner ring is located outside the middle ring. The bottom surface of the first outer ring of the first shaft system is fixedly connected to the base, and the top surface of the first inner ring of the first shaft system is fixedly connected to the first frame. One end face of the second outer ring of the second shaft system is fixedly connected to the first frame, and the other end face of the second inner ring of the second shaft system is fixedly connected to the second frame. The fine-tuning mechanism has a fastening part and a driving part. The fastening part is detachably connected to the middle ring and the inner ring, and the driving part is connected to the middle ring for driving the middle ring to rotate slightly.

[0010] Furthermore, the outer ring includes an outer ring body and an outer ring cover. The inner diameter of the outer ring cover is smaller than the inner diameter of the outer ring body. The outer ring cover is used to detachably connect with the end face of the outer ring body. One end of the middle ring is rotatably disposed inside the outer ring body, and the other end of the middle ring rotatably passes through the outer ring cover and extends out of the outer ring body.

[0011] Furthermore, the middle ring includes a base plate, a middle ring body, and a middle ring cover. The base plate is rotatably disposed inside the outer ring body. One end of the middle ring body is fixedly connected to the base plate. The other end of the middle ring body rotatably passes through the outer ring cover and extends out of the outer ring body. The inner diameter of the middle ring cover is smaller than the inner diameter of the middle ring body. The middle ring cover is used for detachable connection with the end face of the middle ring body. One end of the inner ring is rotatably disposed inside the middle ring body. The other end of the inner ring rotatably passes through the middle ring cover and extends out of the middle ring body.

[0012] Furthermore, the inner ring includes a first inner ring body and a second inner ring body. The first inner ring body is rotatably disposed inside the middle ring body. One end of the second inner ring body is fixedly connected to the first inner ring body, and the other end of the second inner ring body rotatably passes through the middle ring cover and extends out of the middle ring body.

[0013] Furthermore, the first frame includes a base plate, a first vertical plate, a second vertical plate, multiple guide wheels, and guide rings. The base plate is horizontally arranged, and the first and second vertical plates are spaced apart. The bottoms of the first and second vertical plates are fixedly connected to the base plate. The central axes of each guide wheel and guide ring extend horizontally, and one end of each guide wheel is fixedly connected to the second vertical plate. The guide ring is fixedly connected to the arc-shaped wall of each guide wheel. The top surface of the first inner ring is fixedly connected to the base plate, and one end face of the second outer ring is fixedly connected to the first vertical plate. The second frame is disposed above the base plate and between the first and second vertical plates. The inner sidewall of the guide ring is used to abut against the inertial navigation system's (INS) insertion point. During the rotation of the INS, its insertion point can rotate along the inner sidewall of the guide ring.

[0014] Furthermore, the second frame includes a base plate, side plates, and baffles. The side plates and baffles are spaced apart, and the bottoms of the side plates and baffles are fixedly connected to the base plate. The other end face of the second inner ring is fixedly connected to the side plates. The base plate is used to mount an inertial navigation system.

[0015] Furthermore, the fine-tuning mechanism includes a fastener and a driving component. The fastener forms the fastening part and is detachably connected to the middle ring and the inner ring. The driving component forms the driving part and is connected to the middle ring for driving the middle ring to rotate slightly. The first driving component of the first fine-tuning mechanism is disposed on the base, and the second driving component of the second fine-tuning mechanism is disposed on the first vertical plate.

[0016] Furthermore, the fastener is a screw, and a first screw hole is provided on the middle ring. The screw passes through the screw hole and is screwed into the screw hole. The inner end of the screw is used to tighten or loosen the inner ring.

[0017] Furthermore, the driving component is disposed on the side of the shaft system, and includes two fixed seats, a drive shaft, two limiting shafts, two movable seats, two mounting seats, two ear seats, two connecting rods, and a handwheel. The two fixed seats are spaced apart. The drive shaft extends radially along the shaft system, and both ends of the drive shaft are rotatably connected to the two fixed seats one-to-one. The drive shaft is provided with two threads of opposite directions and equal length. The two limiting shafts are respectively disposed on both sides of the drive shaft and are parallel to the drive shaft. The distances from the two limiting shafts to the drive shaft are equal. A second threaded hole is opened in the middle of each of the two movable seats. Two screw holes are screwed into the two threads one-to-one. One end of each of the two movable seats is fixedly connected to one end of the corresponding limiting shaft. Each of the other ends of the two movable seats has a through hole for the corresponding limiting shaft to slide through. Two mounting seats are fixedly sleeved on the two limiting shafts one-to-one. Two ear seats are arranged opposite to each other and are fixedly connected to the middle ring. One end of each of the two connecting rods is hinged to the two mounting seats one-to-one. The other end of each of the two connecting rods is hinged to the two ear seats one-to-one. The handwheel is fixedly connected to the end of the drive shaft away from the shaft system. Rotating the handwheel can drive the drive shaft to rotate.

[0018] Compared with the prior art, the beneficial effects of this utility model include: When calibrating the inertial navigation system (INS), the INS is mounted on the second frame. Since the central axis of the first axis extends vertically, the first axis can rotate relative to the base around its own central axis. The central axis of the second axis extends horizontally, and the second axis can rotate relative to the first frame around its own central axis. By manually rotating the first frame, it can be rotated at any angle in the horizontal plane. Then, by manually rotating the second frame, it can be rotated at any angle in the vertical plane, thereby allowing the INS to reach any attitude. This enables multi-attitude and multi-angle calibration of the INS. After the INS reaches any attitude, the two fine-tuning mechanisms are detachably connected to the two axes one-to-one, and the two fine-tuning mechanisms are operated separately. This allows the axes to be driven to rotate slightly through the fine-tuning mechanisms, thereby fine-tuning the attitude of the INS and improving the calibration accuracy. This INS calibration fixture can achieve multi-attitude and multi-angle calibration of the INS with high calibration accuracy. Attached Figure Description

[0019] Figure 1 This is a three-dimensional structural schematic diagram of an inertial navigation calibration fixture provided by this utility model;

[0020] Figure 2 This is a schematic diagram of the structure of an inertial navigation calibration fixture provided by this utility model;

[0021] Figure 3 This is an exploded view of the fine-tuning mechanism provided by this utility model;

[0022] In the diagram: 1 - Inertial Navigation System, 11 - Aircraft Insertion Device, 100 - Base, 200 - Rotation Mechanism, 210 - Shaft System, 211 - Outer Ring, 2111 - Outer Ring Body, 2112 - Outer Ring Cover, 212 - Middle Ring, 2121 - Base Plate, 2122 - Middle Ring Body, 2123 - Middle Ring Cover, 213 - Inner Ring, 2131 - First Inner Ring Body, 2132 - Second Inner Ring Body, 220 - First Frame, 221 - Base Plate, 222 - 223 - Second vertical plate, 224 - Guide wheel, 225 - Guide ring, 230 - Second frame, 231 - Base plate, 232 - Side plate, 233 - Stop, 300 - Fine adjustment mechanism, 310 - Fastener, 320 - Drive component, 321 - Fixed seat, 322 - Drive shaft, 323 - Limiting shaft, 324 - Moving seat, 325 - Mounting seat, 326 - Ear seat, 327 - Connecting rod, 328 - Handwheel. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this utility model and are not intended to limit this utility model.

[0024] This utility model provides an inertial navigation calibration fixture, the structure of which is as follows: Figure 1 - Figure 3 As shown, the system includes a base 100, a rotating mechanism 200, and two fine-tuning mechanisms 300. The rotating mechanism 200 includes two shaft systems 210, a first frame 220, and a second frame 230. The central axis of the first shaft system 210 extends vertically, and its lower end is connected to the base 100 and can rotate relative to the base 100 around its own central axis. Its upper end is connected to the first frame 220. The central axis of the second shaft system 210 extends horizontally, and one end is connected to the first frame 220 and can rotate relative to the first frame 220 around its own central axis. Its other end is connected to the second frame 230, which is used to mount the inertial navigation system 1. The two fine-tuning mechanisms 300 are detachably connected to the two shaft systems 210 one-to-one and are used to drive the shaft systems 210 to rotate slightly.

[0025] When calibrating inertial navigation system 1, inertial navigation system 1 is mounted on the second frame 230. Since the central axis of the first shaft system 210 extends vertically, the first shaft system 210 can rotate relative to the base 100 around its own central axis. The central axis of the second shaft system 210 extends horizontally, and the second shaft system 210 can rotate relative to the first frame 220 around its own central axis. First, manually rotating the first frame 220 allows it to rotate at any angle in the horizontal plane. Then, manually rotating the second frame 230 allows it to rotate at any angle. The inertial navigation system (INS) can be rotated at any angle in the vertical plane to reach any attitude, enabling multi-attitude and multi-angle calibration of INS. After INS reaches any attitude, the two fine-tuning mechanisms 300 are detachably connected to the two shaft systems 210 in a one-to-one correspondence. The two fine-tuning mechanisms 300 are operated respectively, thereby driving the shaft system 210 to make small rotations, thus fine-tuning the attitude of INS and improving the calibration accuracy. This INS calibration fixture can realize multi-attitude and multi-angle calibration of INS with high calibration accuracy.

[0026] As a preferred embodiment, please refer to Figure 2 and Figure 3The shaft system 210 includes an outer ring 211, a middle ring 212, and an inner ring 213. The outer ring 211, the middle ring 212, and the inner ring 213 are coaxially arranged. One end of the middle ring 212 is disposed inside the outer ring 211 and rotatably connected to the outer ring 211, while the other end of the middle ring 212 is disposed outside the outer ring 211. One end of the inner ring 213 is disposed inside the middle ring 212 and rotatably connected to the middle ring 212, while the other end of the inner ring 213 is disposed outside the middle ring 212. The bottom surface of the first outer ring 211 of the first shaft system 210 is fixedly connected to the base 100. The top surface of the first inner ring 213 of the second shaft system 210 is fixedly connected to the first frame 220. One end face of the second outer ring 211 of the second shaft system 210 is fixedly connected to the first frame 220. The other end face of the second inner ring 213 of the second shaft system 210 is fixedly connected to the second frame 230. The fine-tuning mechanism 300 has a fastening part and a driving part. The fastening part is detachably connected to the middle ring 212 and the inner ring 213. The driving part is connected to the middle ring 212 and is used to drive the middle ring 212 to rotate slightly. When calibrating the inertial navigation system 1, the inertial navigation system 1 is mounted on the second frame 230. Since the first shaft system 210 The central axis of the first frame 220 extends vertically, and the first shaft system 210 can rotate relative to the base 100 around its own central axis. The central axis of the second shaft system 210 extends horizontally, and the second shaft system 210 can rotate relative to the first frame 220 around its own central axis. First, with the middle ring 212 and the inner ring 213 separated, manually rotating the first frame 220 allows the first frame 220 and the first inner ring 213 to rotate at any angle in the horizontal plane. Then, manually rotating the second frame 230 allows the second frame 230 and the second inner ring 213 to rotate at any angle in the vertical plane. This allows the inertial navigation system (INS) 1 to reach any attitude, enabling multi-attitude and multi-angle calibration. After the INS 1 reaches any attitude, the middle ring 212 and the inner ring 213 are detachably connected through the fastening part, putting the middle ring 212 and the inner ring 213 in a connected state. Then, the two driving parts are operated respectively, so that the middle ring 212 and the inner ring 213 can be driven to make small rotations, thereby fine-tuning the attitude of the INS 1. First, the first frame 220 and the second frame 230 are rotated over a large range to make the INS 1 reach any attitude, and then the attitude of the INS 1 is fine-tuned, which can improve the calibration accuracy.

[0027] As a preferred embodiment, please refer to Figure 2 and Figure 3The outer ring 211 includes an outer ring body 2111 and an outer ring cover 2112. The inner diameter of the outer ring cover 2112 is smaller than the inner diameter of the outer ring body 2111. The outer ring cover 2112 is detachably connected to the end face of the outer ring body 2111. One end of the middle ring 212 is rotatably disposed inside the outer ring body 2111, and the other end of the middle ring 212 rotatably passes through the outer ring cover 2112 and extends outside the outer ring body 2111. 12 is detachably connected to the end face of the outer ring body 2111, and the inner diameter of the outer ring cover 2112 is smaller than the inner diameter of the outer ring body 2111, thereby limiting the portion of the middle ring 212 rotatably disposed within the outer ring body 2111, improving the connection strength between the middle ring 212 and the outer ring 211, preventing the rotatable connection between the middle ring 212 and the outer ring 211 from separating, and making it convenient to assemble and disassemble the middle ring 212 and the outer ring 211.

[0028] As a preferred embodiment, please refer to Figure 2 and Figure 3 The middle ring 212 includes a base plate 2121, a middle ring body 2122, and a middle ring cover 2123. The base plate 2121 is rotatably disposed inside the outer ring body 2111. One end of the middle ring body 2122 is fixedly connected to the base plate 2121, and the other end of the middle ring body 2122 rotatably passes through the outer ring cover 2112 and extends outside the outer ring body 2111. The inner diameter of the middle ring cover 2123 is smaller than the inner diameter of the middle ring body 2122. The middle ring cover 2123 is detachably connected to the end face of the middle ring body 2122. One end of the inner ring 213 is rotatably disposed inside the middle ring body 2122, and the other end of the inner ring 213 rotatably passes through the middle ring cover 2122. 3. The base plate 2121 is rotatably disposed inside the outer ring 2111, thereby achieving a rotatable connection between the base plate 2121 and the outer ring 211. The inner ring cover 2123 is detachably connected to the end face of the inner ring 2122, and the inner diameter of the inner ring cover 2123 is smaller than the inner diameter of the inner ring 2122. This limits the portion of the inner ring 213 rotatably disposed inside the inner ring 2122, improves the connection strength between the inner ring 213 and the inner ring 212, prevents the rotatable connection between the inner ring 213 and the inner ring 212 from separating, and facilitates the assembly and disassembly of the inner ring 213 and the inner ring 212.

[0029] As a preferred embodiment, please refer to Figure 2 and Figure 3The inner ring 213 includes a first inner ring body 2131 and a second inner ring body 2132. The first inner ring body 2131 is rotatably disposed inside the middle ring body 2122. One end of the second inner ring body 2132 is fixedly connected to the first inner ring body 2131. The other end of the second inner ring body 2132 rotatably passes through the middle ring cover 2123 and extends out of the middle ring body 2122. The first inner ring body 2131 is rotatably disposed inside the middle ring body 2122, so that it can be rotatably connected to the middle ring 212 via the first inner ring body 2131.

[0030] As a preferred embodiment, please refer to Figure 1 and Figure 2 The first frame 220 includes a base plate 221, a first vertical plate 222, a second vertical plate 223, multiple guide wheels 224, and guide rings 225. The base plate 221 is horizontally arranged. The first vertical plate 222 and the second vertical plate 223 are spaced apart, and the bottoms of the first vertical plate 222 and the second vertical plate 223 are fixedly connected to the base plate 221. The central axes of each guide wheel 224 and the guide ring 225 extend horizontally. One end of each guide wheel 224 is fixedly connected to the second vertical plate 223. The guide ring 225 is fixedly connected to the arc-shaped wall of each guide wheel 224. The top surface of the first inner ring 213 is fixedly connected to the base plate 221, and one end face of the second outer ring 211 is fixedly connected to the base plate 221. The first vertical plate 222 is fixedly connected, and the second frame 230 is disposed above the base plate 221 and located between the first vertical plate 222 and the second vertical plate 223. The inner sidewall of the guide ring 225 is used to abut against the inertial navigation system 1's insertion 11. During the rotation of the inertial navigation system 1, its insertion 11 can rotate along the inner sidewall of the guide ring 225. The structure of the first frame 220 facilitates the installation of the two shaft systems 210 and the inertial navigation system 1. When the inertial navigation system 1 is mounted on the second frame 230, the insertion 11 of the inertial navigation system 1 abuts against the inner sidewall of the guide ring 225, and during the rotation of the inertial navigation system 1, its insertion 11 can rotate along the inner sidewall of the guide ring 225, thereby providing support for the inertial navigation system 1 via the guide ring 225.

[0031] As a preferred embodiment, please refer to Figure 1 and Figure 2The second frame 230 includes a base plate 231, a side plate 232, and a baffle 233. The side plate 232 and the baffle 233 are spaced apart, and the bottom of the side plate 232 and the baffle 233 are fixedly connected to the base plate 231. The other end face of the second inner ring 213 is fixedly connected to the side plate 232. The base plate 231 is used to mount the inertial navigation system 1. The structure of the second frame 230 facilitates the installation of the two shaft systems 210 and the inertial navigation system 1. In use, the inertial navigation system 1 is placed on the base plate 231, and the flight insert 11 of the inertial navigation system 1 is inserted into the guide ring 225. At this time, the arc-shaped wall of the flight insert 11 abuts against the inner side wall of the guide ring 225, and the side of the inertial navigation system 1 near the baffle 233 abuts against the baffle 233. Then, the inertial navigation system 1 is fixedly connected to the base plate 231 by screws.

[0032] As a preferred embodiment, please refer to Figure 2 and Figure 3The fine-tuning mechanism 300 includes a fastener 310 and a drive member 320. The fastener 310 forms the fastening part and is detachably connected to the middle ring 212 and the inner ring 213. The drive member 320 forms the driving part and is connected to the middle ring 212 for driving the middle ring 212 to rotate slightly. The first drive member 320 of the first fine-tuning mechanism 300 is disposed on the base 100, and the second drive member 320 of the second fine-tuning mechanism 300 is disposed on the first vertical plate 222. When calibrating the inertial navigation system 1, the inertial navigation system 1 is placed on the base plate 231. The inertial navigation system 1's insertion 11 is then inserted into the guide ring 225. At this time, the arc-shaped wall of the insertion 11 abuts against the inner wall of the guide ring 225, and the side of the inertial navigation system 1 near the stop 233 abuts against the stop 233. The inertial navigation system 1 is then fixedly connected to the base plate 231 using screws. Since the central axis of the first shaft system 210 extends vertically, the first shaft system 210 can rotate relative to the base 100 around its own central axis. The central axis of the second shaft system 210 extends horizontally, and the second shaft system 210 can rotate relative to the first frame 22. Rotating around its own central axis, firstly separating the middle ring 212 and the inner ring 213, manually rotating the first frame 220 allows the first frame 220 and the first inner ring 213 to rotate at any angle in the horizontal plane. Then, manually rotating the second frame 230 allows the second frame 230 and the second inner ring 213 to rotate at any angle in the vertical plane, thereby enabling the inertial navigation system 1 to reach any attitude and realize the calibration work of the inertial navigation system 1 in multiple attitudes and multiple angles. After the inertial navigation system 1 reaches any attitude, the middle ring 212 can be detachably connected to the fastener 310. The inner ring 213 and the middle ring 212 are connected. Then, the two driving components 320 are operated respectively, so that the middle ring 212 and the inner ring 213 can be driven to rotate slightly through the driving components 320, thereby fine-tuning the attitude of the inertial navigation system 1. First, the first frame 220 and the second frame 230 are rotated in a large range to make the inertial navigation system 1 reach any attitude, and then the attitude of the inertial navigation system 1 is fine-tuned, which can improve the calibration accuracy. This inertial navigation calibration fixture can realize the calibration work of inertial navigation system 1 in multiple attitudes and multiple angles with high calibration accuracy.

[0033] As a preferred embodiment, please refer to Figure 2 and Figure 3 The fastener 310 is a screw. The middle ring 212 has a first screw hole. The screw passes through the screw hole and is screwed into the screw hole. The inner end of the screw is used to tighten or loosen the inner ring 213. By rotating the screw in the forward or reverse direction, the inner end of the screw can tighten or loosen the inner ring 213, thereby enabling the middle ring 212 and the inner ring 213 to be detachably connected.

[0034] As a preferred embodiment, please refer to Figure 2 and Figure 3 The first screw hole is provided on the middle ring body 2122.

[0035] As a preferred embodiment, please refer to Figure 2 and Figure 3 The inner end of the screw is used to press against or release the first inner ring body 2131.

[0036] As a preferred embodiment, please refer to Figure 2 and Figure 3 The driving component 320 is disposed on the side of the shaft system 210, and includes two fixed seats 321, a drive shaft 322, two limiting shafts 323, two movable seats 324, two mounting seats 325, two ear seats 326, two connecting rods 327, and a handwheel 328. The two fixed seats 321 are spaced apart. The drive shaft 322 extends radially along the shaft system 210, and both ends of the drive shaft 322 are rotatably connected to the two fixed seats 321 in a one-to-one correspondence. The drive shaft 322 is provided with two threads of opposite direction and equal length. The two limiting shafts 324, two movable seats 325, two mounting seats 326, two ear seats 327, and a handwheel 328. Shafts 323 are respectively disposed on both sides of the drive shaft 322, and are parallel to the drive shaft 322. The distances from the two limiting shafts 323 to the drive shaft 322 are equal. A second screw hole is provided in the middle of each of the two movable seats 324, and the two second screw holes are screwed into the two corresponding threads. One end of each movable seat 324 is fixedly connected to one end of the corresponding limiting shaft 323. A through hole is provided on the other end of each movable seat 324 for the corresponding limiting shaft 323 to slide through. The mounting base 325 is fixedly sleeved on the two limiting shafts 323 one-to-one. The two ear seats 326 are arranged opposite to each other and are fixedly connected to the middle ring 212. One end of each of the two connecting rods 327 is hinged to the two mounting bases 325 one-to-one, and the other end of each connecting rod 327 is hinged to the two ear seats 326 one-to-one. The handwheel 328 is fixedly connected to the end of the drive shaft 322 away from the shaft system 210. Rotating the handwheel 328 can drive the drive shaft 322 to rotate. By rotating the drive shaft 322 in the forward or reverse direction, due to the two... The movable seat 324 is screwed one-to-one with the two threads of opposite direction and equal length on the drive shaft 322, and both movable seats 324 are restricted by the two limiting shafts 323. When the drive shaft 322 rotates in the forward or reverse direction, the two movable seats 324 will move closer to each other or move further away from each other, thereby causing the two mounting seats 325 to move closer to each other or move further away from each other. During the process of the two mounting seats 325 moving closer to each other or moving further away from each other, the two connecting rods 327 will move in opposite directions, thereby pushing the inner ring 213 to rotate slightly.

[0037] To better understand this utility model, the following is combined with... Figure 1 - Figure 3 The working principle of the technical solution of this utility model will be described in detail below:

[0038] When calibrating the inertial navigation system (INS) 1, it is placed on the base plate 231, and the insertion pin 11 of the INS 1 is inserted into the guide ring 225. At this time, the arc-shaped wall of the insertion pin 11 abuts against the inner wall of the guide ring 225, and the side of the INS 1 near the stop 233 abuts against the stop 233. Then, the INS 1 is fixedly connected to the base plate 231 with screws. Since the central axis of the first axis system 210 extends vertically, the first axis system 210 can rotate relative to the base 100 around its own central axis. The central axis of the second axis system 210 extends horizontally. The second axis 210 can rotate relative to the first frame 220 around its own central axis. First, the middle ring 212 and the inner ring 213 are separated. Manually rotating the first frame 220 allows the first frame 220 and the first inner ring 213 to rotate at any angle in the horizontal plane. Then, manually rotating the second frame 230 allows the second frame 230 and the second inner ring 213 to rotate at any angle in the vertical plane, thereby enabling the inertial navigation system (INS) 1 to reach any attitude. This achieves multi-attitude and multi-angle calibration of the INS 1. Once the INS 1 reaches an arbitrary attitude, it is then... Rotating the screw causes its inner end to press against the inner ring 213, thus connecting the middle ring 212 and the inner ring 213. Then, by manipulating the two driving members 320 to rotate the drive shaft 322 in either the forward or reverse direction, the two movable seats 324 are screwed onto the two oppositely oriented, equal-length threads on the drive shaft 322. Furthermore, both movable seats 324 are constrained by the two limiting shafts 323. Therefore, when the drive shaft 322 rotates in either direction, the two movable seats 324 will move closer together. The two mounting bases 325 may move closer or further apart, causing them to move towards each other or away from each other. During this process, the two connecting rods 327 will move in opposite directions, thereby pushing the inner ring 213 to rotate slightly, thus fine-tuning the attitude of the inertial navigation system 1. By first rotating the first frame 220 and the second frame 230 over a large range to bring the inertial navigation system 1 to any attitude, and then fine-tuning the attitude of the inertial navigation system 1, the calibration accuracy can be improved. This inertial navigation calibration fixture can realize the calibration work of the inertial navigation system 1 in multiple attitudes and angles with high calibration accuracy.

[0039] The inertial navigation calibration fixture provided by this utility model has the following beneficial effects:

[0040] (1) First, make the middle ring 212 and the inner ring 213 separate. Manually rotate the first frame 220 so that the first frame 220 and the first inner ring 213 can rotate at any angle in the horizontal plane. Then manually rotate the second frame 230 so that the second frame 230 and the second inner ring 213 can rotate at any angle in the vertical plane, so that the inertial navigation system 1 can reach any attitude and realize the calibration work of the inertial navigation system 1 in multiple attitudes and multiple angles.

[0041] (2) After the inertial navigation system 1 reaches any attitude, the screw is rotated in the forward direction, so that the inner end of the screw is pressed against the inner ring 213, thereby putting the middle ring 212 and the inner ring 213 in a connected state. Then, the two driving components 320 are operated respectively to rotate the driving shaft 322 in the forward or reverse direction. Since the two moving seats 324 are screwed one-to-one with the two sections of threads with opposite directions and equal lengths on the driving shaft 322, and both moving seats 324 are restricted by the two limiting shafts 323, When the drive shaft 322 rotates in the forward or reverse direction, the two moving seats 324 will move closer to each other or move further away from each other, thereby causing the two mounting seats 325 to move closer to each other or move further away from each other. During the process of the two mounting seats 325 moving closer to each other or moving further away from each other, the two connecting rods 327 will move in opposite directions, thereby pushing the inner ring 213 to rotate slightly. First, rotate the first frame 220 and the second frame 230 in a large range so that the inertial navigation system 1 reaches any attitude. Then, fine-tune the attitude of the inertial navigation system 1 to improve the calibration accuracy.

[0042] (3) This inertial navigation calibration fixture can realize the calibration of inertial navigation 1 in multiple attitudes and angles with high calibration accuracy.

[0043] The specific embodiments of this utility model described above do not constitute a limitation on the scope of protection of this utility model. Any other corresponding changes and modifications made based on the technical concept of this utility model should be included within the scope of protection of the claims of this utility model.

Claims

1. An inertial navigation calibration fixture, characterized in that, include: Base; A rotating mechanism includes two shaft systems, a first frame, and a second frame. The central axis of the first shaft system extends vertically and its lower end is connected to the base and can rotate relative to the base about its own central axis. Its upper end is connected to the first frame. The central axis of the second shaft system extends horizontally and its one end is connected to the first frame and can rotate relative to the first frame about its own central axis. Its other end is connected to the second frame. The second frame is used to mount an inertial navigation system. Two fine-tuning mechanisms are detachably connected to the two shaft systems, one-to-one, for driving the shaft systems to rotate slightly.

2. The inertial navigation calibration fixture according to claim 1, characterized in that, The shaft system includes an outer ring, a middle ring, and an inner ring, which are coaxially arranged. One end of the middle ring is located inside the outer ring and rotatably connected to it, while the other end of the middle ring is located outside the outer ring. One end of the inner ring is located inside the middle ring and rotatably connected to it, while the other end of the inner ring is located outside the middle ring. The bottom surface of the first outer ring of the first shaft system is fixedly connected to the base, and the top surface of the first inner ring of the first shaft system is fixedly connected to the first frame. One end face of the second outer ring of the second shaft system is fixedly connected to the first frame, and the other end face of the second inner ring of the second shaft system is fixedly connected to the second frame. The fine-tuning mechanism has a fastening part and a driving part. The fastening part is detachably connected to the middle ring and the inner ring, and the driving part is connected to the middle ring for driving the middle ring to rotate slightly.

3. The inertial navigation calibration fixture according to claim 2, characterized in that, The outer ring includes an outer ring body and an outer ring cover. The inner diameter of the outer ring cover is smaller than the inner diameter of the outer ring body. The outer ring cover is used to detachably connect to the end face of the outer ring body. One end of the middle ring is rotatably disposed inside the outer ring body, and the other end of the middle ring rotatably passes through the outer ring cover and extends outside the outer ring body.

4. The inertial navigation calibration fixture according to claim 3, characterized in that, The middle ring includes a base plate, a middle ring body, and a middle ring cover. The base plate is rotatably disposed inside the outer ring body. One end of the middle ring body is fixedly connected to the base plate, and the other end of the middle ring body rotatably passes through the outer ring cover and extends out of the outer ring body. The inner diameter of the middle ring cover is smaller than the inner diameter of the middle ring body. The middle ring cover is used for detachable connection with the end face of the middle ring body. One end of the inner ring is rotatably disposed inside the middle ring body, and the other end of the inner ring rotatably passes through the middle ring cover and extends out of the middle ring body.

5. The inertial navigation calibration fixture according to claim 2, characterized in that, The inner ring includes a first inner ring body and a second inner ring body. The first inner ring body is rotatably disposed inside the middle ring body. One end of the second inner ring body is fixedly connected to the first inner ring body, and the other end of the second inner ring body rotatably passes through the middle ring cover and extends out of the middle ring body.

6. The inertial navigation calibration fixture according to claim 2, characterized in that, The first frame includes a base plate, a first vertical plate, a second vertical plate, multiple guide wheels, and guide rings. The base plate is horizontally positioned. The first and second vertical plates are spaced apart, and the bottoms of both the first and second vertical plates are fixedly connected to the base plate. The central axes of each guide wheel and guide ring extend horizontally. One end of each guide wheel is fixedly connected to the second vertical plate. The guide ring is fixedly connected to the arc-shaped wall of each guide wheel. The top surface of the first inner ring is fixedly connected to the base plate, and one end face of the second outer ring is fixedly connected to the first vertical plate. The second frame is positioned above the base plate and between the first and second vertical plates. The inner sidewall of the guide ring is used to abut against the inertial navigation system's (INS) insertion point. During INS rotation, the insertion point can rotate along the inner sidewall of the guide ring.

7. The inertial navigation calibration fixture according to claim 6, characterized in that, The second frame includes a base plate, side plates, and baffles. The side plates and baffles are spaced apart, and the bottoms of the side plates and baffles are fixedly connected to the base plate. The other end face of the second inner ring is fixedly connected to the side plates. The base plate is used to mount an inertial navigation system.

8. The inertial navigation calibration fixture according to claim 6, characterized in that, The fine-tuning mechanism includes a fastener and a drive component. The fastener forms the fastening part and is detachably connected to the middle ring and the inner ring. The drive component forms the driving part and is connected to the middle ring for driving the middle ring to rotate slightly. The first drive component of the first fine-tuning mechanism is disposed on the base, and the second drive component of the second fine-tuning mechanism is disposed on the first vertical plate.

9. The inertial navigation calibration fixture according to claim 8, characterized in that, The fastener is a screw, and a first screw hole is provided on the middle ring. The screw passes through the screw hole and is screwed into the screw hole. The inner end of the screw is used to tighten or loosen the inner ring.

10. The inertial navigation calibration fixture according to claim 8, characterized in that, The driving component is disposed on the side of the shaft system and includes two fixed seats, a drive shaft, two limiting shafts, two movable seats, two mounting seats, two lugs, two connecting rods, and a handwheel. The two fixed seats are spaced apart. The drive shaft extends radially along the shaft system, and its two ends are rotatably connected to the two fixed seats one-to-one. The drive shaft is provided with two threads of opposite directions and equal length. The two limiting shafts are respectively disposed on both sides of the drive shaft and are parallel to the drive shaft, with equal distances from the two limiting shafts to the drive shaft. A second threaded hole is provided in the middle of each of the two movable seats. The two movable seats are screwed one-to-one with the two threads. One end of each movable seat is fixedly connected to one end of the corresponding limiting shaft. Each movable seat has a through hole at the other end for the corresponding limiting shaft to slide through. The two mounting seats are fixedly sleeved on the two limiting shafts one-to-one. The two lugs are arranged opposite each other and fixedly connected to the middle ring. One end of each connecting rod is hinged to the two mounting seats one-to-one, and the other end of each connecting rod is hinged to the two lugs one-to-one. The handwheel is fixedly connected to the end of the drive shaft away from the shaft system. Rotating the handwheel can drive the drive shaft to rotate.

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