A precision adjustment device and error compensation method for realizing coaxiality of inertial navigation shaft system

Abstract

The application relates to a precision assembling and adjusting device and an error compensation method for realizing inertial navigation shaft system coaxiality, characterized in that a mandrel assembly comprises a cylinder body, a transmission mandrel, a positioning end cover and a guide end cover; a coaxial positioning and adjusting assembly comprises six positioning guide columns, left and right tension driving elements, six micro piezoelectric actuators and a hand wheel; the six positioning guide columns are respectively gap-inserted into six insertion holes on the side wall of the cylinder body; the two tension driving elements are respectively connected to the positive threaded section and the reverse threaded section of the transmission mandrel and respectively form wedge-shaped cooperation with the two ends of the six positioning guide columns; the six micro piezoelectric actuators are respectively installed in six radial installation holes in the guide end cover; the hand wheel is connected to the exposed end of the transmission mandrel; six groups of micro laser displacement sensors are respectively installed in axial installation holes on the six positioning guide columns, and an integrated sensor module is fixedly installed in the guide end cover; a control unit is used for completing error data collection, processing, compensation calculation and driving control of the micro piezoelectric actuators. The application realizes working condition self-adaptive error compensation.

Description

Technical Field

[0001] This invention relates to the field of precision assembly and adjustment technology in mechanical manufacturing, specifically designing a device and error compensation method for achieving precise assembly and adjustment of the coaxiality of inertial navigation shaft systems. Background Technology

[0002] As a high-precision navigation device, the coaxiality of the inertial navigation system (INS) directly determines its navigation accuracy. Existing assembly and adjustment technologies suffer from three major pain points: First, traditional assembly and adjustment rely on manual experience to operate standard gauge blocks, with each calibration covering only 1-2 measurement points, failing to capture full-circumference errors and easily missing local out-of-tolerance areas. Second, existing positioning structures mostly use rigid contact positioning, which is prone to stress concentration during assembly and adjustment, leading to micro-deformation of the INS and introducing additional assembly errors. Furthermore, repeated disassembly and testing are required after adjustment, resulting in an assembly and adjustment efficiency of less than 3 times per hour. Third, the lack of a dynamic error compensation mechanism means that coaxiality calibration can only be completed under static conditions, ignoring the INS's positional shifts caused by temperature changes and vibration shocks during operation. In actual working conditions, coaxiality errors can increase by 15%-20%, failing to meet the requirements of high-precision navigation. Summary of the Invention

[0003] To address the shortcomings of existing technologies, this invention proposes a device and error compensation method for achieving precise alignment of inertial navigation system coaxiality.

[0004] One of the above-mentioned objectives of the present invention is achieved by the following technical solution:

[0005] A device for precise adjustment of coaxiality of an inertial navigation system includes a spindle assembly, a detection assembly, a coaxial positioning and adjustment assembly, and a control unit;

[0006] The mandrel assembly consists of a cylinder body, a transmission mandrel, a positioning end cover, and a guide end cover; the left and right ends of the cylinder body are positioned and fixedly connected to the positioning end cover and the guide end cover respectively through positioning stops; the transmission mandrel passes through the mandrel through hole in the center of the cylinder body, and its two ends are rotatably supported by the positioning end cover and the guide end cover respectively.

[0007] The coaxial positioning and adjustment assembly includes six positioning guide posts, a left tensioning drive and a right tensioning drive, six miniature piezoelectric actuators, and a handwheel or drive motor. The six positioning guide posts are respectively inserted into six axially evenly distributed insertion holes on the side wall of the cylinder body, located around the mandrel through hole, with clearance fit. The left and right tensioning drives are respectively connected to the forward and reverse threaded sections of the transmission mandrel, and form a wedge fit with the two ends of the six positioning guide posts. The six miniature piezoelectric actuators are respectively installed in six radially arranged mounting holes on the guide end cover. The handwheel or drive motor is connected to the exposed end of the transmission mandrel.

[0008] The detection assembly includes six sets of miniature laser displacement sensors and an integrated sensor module. The six sets of miniature laser displacement sensors are respectively installed in the axial mounting holes on the six positioning guide posts to collect radial runout data of the entire circumference of the shaft system's inner hole in real time. The integrated sensor module is fixedly installed inside the guide end cover and contains a temperature sensor and a triaxial acceleration sensor. The temperature sensor is used to detect the internal temperature of the assembly and adjustment device. The triaxial acceleration sensor is used to detect the vibration acceleration of the assembly and adjustment device. The sensor signals are connected to the control unit via a wireless transmission module to achieve non-contact real-time detection.

[0009] The control unit is used to complete error data acquisition, processing, compensation calculation, and drive control of the micro piezoelectric actuator, and supports data export and historical record query.

[0010] Furthermore, the two ends of the positioning guide post are provided with tapered heads; the left tensioning drive and the right tensioning drive are tapered sleeves with internal threaded holes, and the taper of the outer tapered surface is consistent with the taper of the tapered heads at both ends of the positioning guide post; the left tensioning drive and the right tensioning drive contact the tapered heads at both ends of the six positioning guide posts respectively to form a wedge fit.

[0011] Furthermore, the forward and reverse threaded sections on the transmission mandrel, as well as the internal threads of the left and right tensioning drive components, all adopt precision fine threads, with a transmission accuracy of 0.001mm.

[0012] Furthermore, end holes with a diameter larger than the mandrel through hole are provided at both ends of the cylinder body. The end holes at both ends intersect with six insertion holes, making the two ends of the cylinder body open in a six-point shape. A set of axially arranged guide grooves are provided on the inner walls of the end holes at both ends of the cylinder body. A set of guide ribs are provided on the outer surfaces of the left tension drive and the right tension drive. The guide ribs form a guide fit with the guide grooves at the corresponding ends of the cylinder body, realizing the circumferential positioning of the left tension drive and the right tension drive.

[0013] Moreover, the resolution of the micro laser displacement sensor is 0.1 μm.

[0014] Furthermore, the control unit includes an embedded control unit, a touch display screen, and a data storage module.

[0015] The second objective of this invention is achieved through the following technical solution:

[0016] An error compensation method based on the above-mentioned device for precise adjustment of inertial navigation system coaxiality includes the following steps:

[0017] Step 1: Prepare for assembly and adjustment, including:

[0018] Step 1.1, Standard Calibration: Install the assembly and adjustment device on the standard calibration table, use the standard controlled gauge, start the detection component, collect full-circumference error data, compare with the standard value, calibrate the laser displacement sensor, and ensure that the detection error is ≤ ±0.5. Among them, the accuracy of the standard controlled gauge is 1. ;

[0019] Step 1.2, Workpiece pretreatment: Clean the two ends of the shaft holes of the inertial navigation inner frame to be assembled and adjusted, remove oil and impurities, measure the basic dimensions of the shaft holes, including diameter D and length L, input them into the control unit, and preset the tensioning and positioning parameters;

[0020] Step 2: Perform assembly, adjustment, and error compensation procedures.

[0021] Step 2.1: Install the device: Pass the two sets of precision assembly devices through the left and right shaft holes of the inertial navigation inner frame respectively, and ensure that the middle cylinder of the six positioning guides fits the left and right shaft holes of the inner frame to initially select the position of the device.

[0022] Step 2.2, Perform tensioning and positioning: Rotate the handwheel at the outer end of the transmission spindle clockwise or start the servo motor to drive the left tensioning drive 31 and the right tensioning drive 32 to move towards each other. Through the wedge action on both sides, the six positioning guide pins move slightly outward in the radial direction and contact the inner walls of the left and right end shaft holes. When the tensioning force reaches the preset value, stop rotating to complete the initial positioning.

[0023] Step 2.3: Perform full circumference inspection: Start the inspection component, and six sets of laser displacement sensors collect 360° radial runout data of the inner hole of the shaft system, generate an error cloud map, and determine the location and value of the maximum error point;

[0024] Step 2.4: Perform operating condition compensation: The control unit reads the current temperature T and vibration acceleration a, calculates the total offset, and drives the miniature piezoelectric actuator 34 to adjust the positioning position based on the total offset, correcting the position of the positioning guide post. After correction, it checks again until the coaxiality error is ≤ ±0.5. ;

[0025] Step 2.5, Inner Frame Assembly: After the coaxiality is qualified, install the inner frame into the outer frame and tighten the connecting screws according to the specified torque. Monitor the coaxiality change in real time during the process. If the error exceeds the tolerance, repeat step 2.4.

[0026] Step 3: Disassemble and adjust the assembly: After the inner frame is fixed, rotate the handwheel counterclockwise or start the servo motor to loosen the positioning guide post, and slowly remove the two sets of adjustment devices to complete the assembly.

[0027] Furthermore, in step 2.4, the total offset is calculated by establishing a temperature-vibration-error mapping model, which includes the following steps:

[0028] Step 2.4.1, Definition of basic parameters

[0029] Coefficient of thermal expansion of shaft material: Unit: 1 / ;

[0030] Standard temperature: Current measured temperature: ,unit: ;

[0031] Effective length of the shaft system: L, unit: m, determined by actual measurement of the spacing between the shaft holes in the inner frame;

[0032] Triaxial vibration acceleration: , , Unit: m / ;

[0033] Vibration influence coefficient: ,unit: , Due to material density Shaft diameter d fitting, ;

[0034] Basic assembly errors: ,unit: The value is determined by the initial detection value of the laser displacement sensor;

[0035] Piezoelectric hysteresis correction factor: The value is 0.98-1.02, calibrated using the Preisach model.

[0036] Total compensation: ,unit: ;

[0037] Step 2.4.2: Establish an error compensation model

[0038] Determine the thermal deformation error

[0039] Based on the law of thermal expansion of materials, the radial deformation of the shaft system due to temperature change is:

[0040]

[0041] in: Used to convert meter-level deformation to micrometer-level deformation.

[0042] Determine vibration offset error :

[0043] Based on the principles of inertial mechanics, the radial offset of the shaft system caused by vibration is calculated by combining the triaxial accelerations:

[0044]

[0045] Calibration through experiments

[0046] The total compensation amount is determined based on thermal deformation error, vibration offset error, and basic assembly error. :

[0047] Considering the basic assembly error and the correction for piezoelectric hysteresis effect, the formula for the total compensation is:

[0048] .

[0049] The advantages and positive effects of this invention are as follows:

[0050] 1. This invention adopts a full-circumference dynamic detection module integrated design: a miniature laser displacement sensor is embedded in the positioning guide post of the device. The device has 6 positioning guide posts (60° apart) evenly distributed along the circumference, which can collect the radial runout data of the entire circumference of the shaft system in real time. Combined with the data processing unit, a 360° error cloud map is generated, which solves the problem of missed detection in traditional single-point detection and improves the detection accuracy to ±0.5μm.

[0051] 2. This invention adopts a flexible adaptive positioning mechanism: the original rigid tensioning positioning actuator is replaced with a composite structure of "metal frame + radial tensioning transmission connection". The radial tensioning transmission structure can be adjusted by forward and reverse spiral extrusion (0.2-0.5mm), forming flexible contact during positioning to avoid micro-deformation of the shaft system. At the same time, the tensioning force can be precisely controlled at 5-15N, adapting to the assembly and adjustment needs of shaft systems of different materials (such as aluminum alloy and titanium alloy).

[0052] 3. This invention employs a multi-condition error compensation algorithm: establishing a temperature-vibration-error mapping model, and using an integrated temperature sensor (range -40) to compensate for the error. -85 The system uses a triaxial accelerometer to collect operating parameters in real time, substitutes them into a preset compensation formula to calculate the shaft offset, drives a micro piezoelectric actuator (forming ±5μm) to dynamically correct the positioning position, realizes adaptive error compensation under operating conditions, and controls the coaxiality error under actual operating conditions within 5μm. Attached Figure Description

[0053] Figure 1 This is an overall sectional view of the device for precise adjustment of coaxiality of inertial navigation systems according to the present invention.

[0054] Figure 2 This is an exploded perspective view of the device for precise adjustment of coaxiality of inertial navigation systems according to the present invention. Detailed Implementation

[0055] The structure of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0056] Please refer to the following for a device that enables precise adjustment of the coaxiality of an inertial navigation system. Figures 1-2 The invention's key components include a mandrel assembly, a detection assembly, a coaxial positioning and adjustment assembly, and a control unit, with the specific structure as follows:

[0057] The spindle assembly consists of a cylinder body 11, a drive spindle 12, a positioning end cover 13, and a guide end cover 14. The cylinder body 11 is made of high-strength stainless steel. The left and right ends of the cylinder body are positioned with the positioning end cover 13 and the guide end cover 14 respectively through positioning stops and are fixed with bolts. The coaxiality tolerance is controlled within 2μm. After connection, it is ensured that the central axis of the positioning end cover 13 and the central axis of the guide end cover 14 are coincident, ensuring the flexibility and stability of the rotation of the drive spindle 12.

[0058] The cylinder body has a mandrel through hole at its center. Six axial insertion holes are evenly distributed circumferentially around the mandrel through hole on the side wall of the cylinder body. End holes with a diameter larger than the mandrel through hole are provided at both ends of the cylinder body, intersecting with the six insertion holes, making the two ends of the cylinder body open in a six-point shape. A set of axially aligned guide grooves are provided on the inner walls of the end holes at both ends of the cylinder body.

[0059] The transmission mandrel consists of a middle section, forward threaded sections and reverse threaded sections on both sides of the middle section, and two support sections at both ends of the transmission mandrel. The transmission mandrel is fitted into the mandrel through hole on the cylinder body through the middle section. The support sections at both ends are rotatably supported by bearings in the inner holes of the positioning end cover and the guide end cover, respectively. One end of the transmission mandrel extends out from the guide end cover, forming the drive end of the transmission mandrel.

[0060] The guide end cap has six radial mounting holes evenly distributed along the circumferential direction on its side wall. These six radial mounting holes correspond one-to-one with the six axial insertion holes on the cylinder body in the axial direction.

[0061] Coaxial positioning and adjustment assembly: includes six positioning guide posts 33, a left tensioning drive 31 and a right tensioning drive 32, six miniature piezoelectric actuators 34, a handwheel 35 or a drive motor, to achieve tensioning and error correction.

[0062] The positioning guide post has tapered heads at both ends. Six positioning guide posts are inserted into six insertion holes on the cylinder body with a clearance fit. The two ends of each positioning guide post contact the inner ends of the positioning end cap and the guide end cap, respectively, achieving axial positioning. Additionally, an axial mounting hole is provided on one end of each positioning guide post near the guide end cap. The left and right tensioning drive components are tapered sleeves with internal threaded holes, and the taper of their outer tapered surfaces matches the taper of the tapered heads at both ends of the positioning guide posts. The left and right tensioning drive components are threaded to the forward and reverse threaded sections of the transmission spindle, respectively, and contact the tapered heads at both ends of the six positioning guide posts. In this invention, the forward and reverse threaded sections of the transmission spindle, as well as the internal threads of the left and right tensioning drive components, all use precision fine threads, achieving a transmission accuracy of 0.001 mm. In addition, a set of guide ribs are provided on the outer surfaces of the left and right tensioning drive components. The guide ribs and the guide grooves at the corresponding ends of the cylinder body form a guiding fit to restrict the rotation of the left and right tensioning drive components in the circumferential direction.

[0063] The six miniature piezoelectric actuators are respectively installed in the six mounting holes on the guide end cap.

[0064] The handwheel or drive motor is connected to the drive end of the transmission spindle and is used to output the driving force for rotating the transmission spindle.

[0065] The detection component comprises six sets of miniature laser displacement sensors 21 and an integrated sensor module 22. The six sets of miniature laser displacement sensors are respectively installed in the axial mounting holes on the six positioning guide posts, acquiring real-time radial runout data of the entire circumference of the shaft system's inner hole. The integrated sensor module is fixedly installed inside the guide end cover and includes a built-in temperature sensor and a triaxial accelerometer. The temperature sensor detects the internal temperature of the assembly / adjustment device, and the triaxial accelerometer detects the vibration acceleration of the assembly / adjustment device. The sensor signals are transmitted to the control unit via a wireless transmission module, enabling non-contact real-time detection. The resolution of the miniature laser displacement sensors is 0.1 μm.

[0066] Control Unit: Includes an embedded control unit, a touch screen, and a data storage module, used to complete error data acquisition, processing, compensation calculation, and drive control, and supports data export and historical record query.

[0067] An error compensation method based on the above-mentioned device for precise adjustment of inertial navigation system coaxiality includes the following steps:

[0068] Step 1: Prepare for assembly and adjustment, including:

[0069] Step 1.1, Standard Calibration: Install the assembly and adjustment device on the standard calibration table, use the standard controlled gauge, start the detection component, collect full-circumference error data, compare with the standard value, calibrate the laser displacement sensor, and ensure that the detection error is ≤ ±0.5. Among them, the accuracy of the standard controlled gauge is 1. ;

[0070] Step 1.2, Workpiece pretreatment: Clean the two end shaft holes of the inertial navigation inner frame to be assembled and adjusted, remove oil and impurities, measure the basic dimensions of the shaft holes, including diameter D and length L, input them into the control unit, and preset the tensioning and positioning parameters.

[0071] Step 2: Perform assembly, adjustment, and error compensation procedures.

[0072] Step 2.1: Install the device: Pass the two sets of precision assembly devices through the left and right shaft holes of the inertial navigation inner frame respectively, and ensure that the middle cylindrical position of the six positioning guide posts 33 fits the left and right shaft holes of the inner frame to initially select the position of the device.

[0073] Step 2.2: Perform tensioning and positioning: Rotate the handwheel at the outer end of the transmission spindle clockwise or start the servo motor to drive the left tensioning drive 31 and the right tensioning drive 32 to move towards each other. Through the wedge action on both sides, the six positioning guide posts move slightly outward in the radial direction, contacting the inner walls of the left and right end shaft holes. When the tension force reaches the preset value, stop rotating to complete the initial positioning. The tension force in this invention is controlled by the following measures, which can be selected individually or in combination:

[0074] 1) Mechanical limit: A limit structure is set on the tensioning drive / transmission spindle to limit the maximum radial displacement of the guide column and lock the maximum tensioning force;

[0075] 2.) Drive force control: The handwheel is equipped with a torque wrench / torque limiting mechanism, and the servo motor has a torque upper limit, controlling the tension force through torque control;

[0076] 3.) Sensing closed loop: Install force / displacement sensors to feed back data to the control unit, and stop when the target is reached, so as to accurately control the force.

[0077] Step 2.3: Perform full circumference inspection: Start the inspection component, and six sets of laser displacement sensors collect 360° radial runout data of the inner hole of the shaft system, generate an error cloud map, and determine the location and value of the maximum error point;

[0078] Step 2.4: Perform operating condition compensation: The control unit reads the current temperature T and vibration acceleration a, calculates the total offset, and drives the miniature piezoelectric actuator 34 to adjust the positioning position based on the total offset, correcting the position of the positioning guide post. After correction, it checks again until the coaxiality error is ≤ ±0.5. ;

[0079] Step 2.5, Inner Frame Assembly: After the coaxiality is qualified, install the inner frame into the outer frame and tighten the connecting screws according to the specified torque. Monitor the coaxiality change in real time during the process. If the error exceeds the tolerance, repeat step 2.4.

[0080] Step 3: Disassemble and adjust the assembly: After the inner frame is fixed, rotate the handwheel counterclockwise or start the servo motor to loosen the positioning guide post, and slowly remove the two sets of adjustment devices to complete the assembly.

[0081] In step 2.4 above, the total offset is calculated by establishing a temperature-vibration-error mapping model. The error mapping model is based on the superposition principle of "thermal deformation error + vibration offset error + basic assembly error", and is established by multi-sensor data fusion. The core derivation process is as follows:

[0082] I. Basic Parameter Definitions

[0083] 1. Coefficient of thermal expansion of shaft system material: Unit: 1 / Aluminum alloy Titanium alloy );

[0084] 2. Standard temperature: Current measured temperature: ,unit: ;

[0085] 3. Effective length of the shaft system: L, unit: m, determined by actual measurement of the spacing between the shaft holes in the inner frame;

[0086] 4. Triaxial vibration acceleration: , , Unit: m / ;

[0087] 5. Vibration influence coefficient: ,unit: Due to material density Shaft diameter d fitting, ;

[0088] 6. Basic assembly errors: ,unit: The value is determined by the initial detection value of the laser displacement sensor;

[0089] 7. Piezoelectric hysteresis correction factor: The value is 0.98-1.02, calibrated using the Preisach model.

[0090] 8. Total compensation: ,unit: .

[0091] II. Establishing an Error Compensation Model

[0092] 1. Determine the thermal deformation error

[0093] Based on the law of thermal expansion of materials, the radial deformation of the shaft system due to temperature change is:

[0094]

[0095] in: Used to convert meter-level deformation to micrometer-level deformation.

[0096] 2. Determine the vibration offset error

[0097] Based on the principles of inertial mechanics, the radial offset of the shaft system caused by vibration is calculated by combining the triaxial accelerations:

[0098]

[0099] (Note: Through experimental calibration, for example, when the aluminum alloy shaft system has a d=20mm... )

[0100] 3. Determine the total compensation amount based on thermal deformation error, vibration offset error, and basic assembly error. :

[0101] Considering the basic assembly error and the correction for piezoelectric hysteresis effect, the formula for the total compensation is:

[0102] .

[0103] Although embodiments and drawings of the present invention have been disclosed for illustrative purposes, those skilled in the art will understand that various substitutions, variations and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments and drawings.

Claims

1. A device for precise adjustment of the coaxiality of an inertial navigation system, characterized in that: Includes a spindle assembly, a detection assembly, a coaxial positioning and adjustment assembly, and a control unit; The mandrel assembly consists of a cylinder body, a transmission mandrel, a positioning end cover, and a guide end cover; the left and right ends of the cylinder body are positioned and fixedly connected to the positioning end cover and the guide end cover respectively through positioning stops; the transmission mandrel passes through the mandrel through hole in the center of the cylinder body, and its two ends are rotatably supported by the positioning end cover and the guide end cover respectively. The coaxial positioning and adjustment assembly includes six positioning guide posts, a left tensioning drive and a right tensioning drive, six miniature piezoelectric actuators, and a handwheel or drive motor. The six positioning guide posts are respectively inserted into six axially evenly distributed insertion holes on the side wall of the cylinder body, located around the mandrel through hole, with clearance fit. The left and right tensioning drives are respectively connected to the forward and reverse threaded sections of the transmission mandrel, and form a wedge fit with the two ends of the six positioning guide posts. The six miniature piezoelectric actuators are respectively installed in six radially arranged mounting holes on the guide end cover. The handwheel or drive motor is connected to the exposed end of the transmission mandrel. The detection assembly includes six sets of miniature laser displacement sensors and an integrated sensor module. The six sets of miniature laser displacement sensors are respectively installed in the axial mounting holes on the six positioning guide posts to collect radial runout data of the entire circumference of the shaft system's inner hole in real time. The integrated sensor module is fixedly installed inside the guide end cover and contains a temperature sensor and a triaxial acceleration sensor. The temperature sensor is used to detect the internal temperature of the assembly and adjustment device. The triaxial acceleration sensor is used to detect the vibration acceleration of the assembly and adjustment device. The sensor signals are connected to the control unit via a wireless transmission module to achieve non-contact real-time detection. The control unit is used to complete error data acquisition, processing, compensation calculation, and drive control of the micro piezoelectric actuator, and supports data export and historical record query.

2. The device for precise adjustment of coaxiality of inertial navigation systems according to claim 1, characterized in that: The positioning guide post has tapered heads at both ends; the left and right tensioning drive components are tapered sleeves with internal threaded holes, and the taper of the outer tapered surface is consistent with the taper of the tapered heads at both ends of the positioning guide post; the left and right tensioning drive components contact the tapered heads at both ends of the six positioning guide posts to form a wedge fit.

3. The device for precise adjustment of coaxiality of inertial navigation systems according to claim 2, characterized in that: The forward and reverse threaded sections on the transmission mandrel, as well as the internal threads of the left and right tensioning drive components, all adopt precision fine threads, with a transmission accuracy of 0.001mm.

4. The device for precise adjustment of coaxiality of inertial navigation systems according to claim 2, characterized in that: The cylinder body has end holes at both ends with a diameter larger than that of the mandrel through hole. The end holes at both ends intersect with six insertion holes, making the two ends of the cylinder body open in a six-point shape. A set of axially arranged guide grooves are provided on the inner walls of the end holes at both ends of the cylinder body. A set of guide ribs are provided on the outer surfaces of the left and right tensioning drive components. The guide ribs form a guide fit with the guide grooves at the corresponding ends of the cylinder body, thereby limiting the left and right tensioning drive components in the circumferential direction.

5. The device for precise adjustment of coaxiality of inertial navigation systems according to claim 1, characterized in that: The resolution of the miniature laser displacement sensor is 0.1 μm.

6. The device for precise adjustment of coaxiality of inertial navigation systems according to claim 1, characterized in that: The control unit includes an embedded control unit, a touch screen display, and a data storage module.

7. An error compensation method based on the precision assembly and adjustment device for coaxiality of an inertial navigation system according to any one of claims 1-6, characterized in that, Includes the following steps: Step 1: Prepare for assembly and adjustment, including: Step 1.1, Standard Calibration: Install the assembly and adjustment device on the standard calibration table, use the standard controlled gauge, start the detection component, collect full-circumference error data, compare with the standard value, calibrate the laser displacement sensor, and ensure that the detection error is ≤ ±0.

5. Among them, the accuracy of the standard controlled gauge is 1. ; Step 1.2, Workpiece pretreatment: Clean the two ends of the shaft holes of the inertial navigation inner frame to be assembled and adjusted, remove oil and impurities, measure the basic dimensions of the shaft holes, including diameter D and length L, input them into the control unit, and preset the tensioning and positioning parameters; Step 2: Perform assembly, adjustment, and error compensation procedures. Step 2.1: Install the device: Pass the two sets of precision assembly devices through the left and right shaft holes of the inertial navigation inner frame respectively, and ensure that the middle cylinder of the six positioning guides fits the left and right shaft holes of the inner frame to initially select the position of the device. Step 2.2, Perform tensioning and positioning: Rotate the handwheel at the outer end of the transmission spindle clockwise or start the servo motor to drive the left and right tensioning drive components to move towards each other. Through the wedge action on both sides, the six positioning guide pins move slightly outward in the radial direction and contact the inner walls of the left and right end shaft holes. When the tensioning force reaches the preset value, stop rotating to complete the initial positioning. Step 2.3: Perform full circumference inspection: Start the inspection component, and six sets of laser displacement sensors collect 360° radial runout data of the inner hole of the shaft system, generate an error cloud map, and determine the location and value of the maximum error point; Step 2.4: Perform operating condition compensation: The control unit reads the current temperature T and vibration acceleration a, calculates the total offset, and drives the miniature piezoelectric actuator to adjust the positioning position based on the total offset, correcting the position of the positioning guide post. After correction, it checks again until the coaxiality error is ≤ ±0.

5. ; Step 2.5, Inner Frame Assembly: After the coaxiality is qualified, install the inner frame into the outer frame and tighten the connecting screws according to the specified torque. Monitor the coaxiality change in real time during the process. If the error exceeds the tolerance, repeat step 2.

4. Step 3: Disassemble and adjust the assembly: After the inner frame is fixed, rotate the handwheel counterclockwise or start the servo motor to loosen the positioning guide post, and slowly remove the two sets of adjustment devices to complete the assembly.

8. The error compensation method according to claim 7, characterized in that, In step 2.4, the total offset is calculated by establishing a temperature-vibration-error mapping model, including the following steps: Step 2.4.1, Definition of basic parameters Coefficient of thermal expansion of shaft material: Unit: 1 / ; Standard temperature: Current measured temperature: ,unit: ; Effective length of the shaft system: L, unit: m, determined by actual measurement of the spacing between the shaft holes in the inner frame; Triaxial vibration acceleration: , , Unit: m / ; Vibration influence coefficient: ,unit: Due to material density Shaft diameter d fitting, ; Basic assembly errors: ,unit: The value is determined by the initial detection value of the laser displacement sensor; Piezoelectric hysteresis correction factor: The value is 0.98-1.02, calibrated using the Preisach model. Total compensation: ,unit: ; Step 2.4.2: Establish an error compensation model Determine the thermal deformation error : Based on the law of thermal expansion of materials, the radial deformation of the shaft system due to temperature change is: in: Used to convert meter-level deformation to micrometer-level deformation. Determine vibration offset error : Based on the principles of inertial mechanics, the radial offset of the shaft system caused by vibration is calculated by combining the triaxial accelerations: ； Calibration was achieved through experiments; The total compensation amount is determined based on thermal deformation error, vibration offset error, and basic assembly error. : Considering the basic assembly error and the correction for piezoelectric hysteresis effect, the formula for the total compensation is: 。

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