Force thermal deformation simulation measurement method of inertial measurement device and computer program product

Abstract

The invention discloses a force thermal deformation simulation measurement method for an inertial measurement device and a computer program product. The method comprises the following steps: calculating structure overall deformation information caused by heat by adopting a structure thermodynamic simulation method; space coordinates of the discrete nodes after deformation are calculated by extracting the original space position information of the discrete nodes at the target position and the three-dimensional variable quantity of the discrete nodes caused by heat; a least square space surface fitting method is adopted to obtain a space surface equation formed by discrete nodes after deformation and a normal vector of the space surface equation; and according to the included angle between the fitting surface normal vector and the related coordinate system vector, heat-caused micro angular deformation of the high-precision inertial device of the inertial measurement device is obtained. According to the method, the second-level micro angular deformation of the mounting surface of the high-precision inertial device caused by heat of the inertial measurement device is measured, and the problem that the inertial measurement device cannot accurately evaluate the micro angular deformation for a long time is solved; the method is of great significance to subsequent optimization of thermal field distribution of the inertial measurement system and improvement of measurement precision and long-term stability of the system.

Description

Technical Field

[0001] The present invention relates to the technical field of micro-deformation measurement of an inertial measurement device, and in particular to a method for simulating and measuring mechanical and thermal deformation of an inertial measurement device. Background Art

[0002] As an important part of the inertial navigation system, the inertial measurement unit (IMU) is sensitive to the attitude and position changes of moving objects through the high-precision inertial devices (gyroscopes and accelerometers) installed on it. Since the working accuracy of the inertial device is easily affected by the ambient temperature, and the complex thermal field environment and displacement changes in the IMU will cause the working temperature of the gyroscope and accelerometer to fluctuate, thus causing measurement errors of the inertial device, resulting in the accuracy of the inertial navigation system being affected. Furthermore, as the structure is the installation reference of the inertial device, quantitative analysis of the impact of the thermal field on the installation surface of the inertial device is an important prerequisite and basis for realizing the structural optimization design and error compensation of the inertial measurement device.

[0003] The temperature field in the inertial measurement device is complexly coupled, including heat sources such as inertial instruments, heating plates, torque motors and related circuit modules, as well as fans arranged for temperature diffusion. Since the inertial measurement device is a closed system when working, the high-precision inertial devices are located inside the device. The non-contact optical method cannot enter the mounting surface to be measured from the outside to achieve small deformation measurement. When using the direct contact strain gauge measurement method, the deformation of the mounting surface itself is small and difficult to measure. In addition, the systematic error introduced by the strain gauge makes the measurement accuracy even more difficult to guarantee. Therefore, how to accurately measure the influence of the thermal field on the mounting surface of the high-precision inertial instrument of the inertial measurement device, realize the accurate calculation of the angular deformation of the mounting surface, and provide data support for structural design and system error compensation has become an urgent problem to be solved in the engineering of inertial measurement devices. Summary of the invention

[0004] The technical problem solved by the present application is: to overcome the deficiencies of the prior art, to provide a method for simulating the measurement of mechanical and thermal deformation of an inertial measurement device, to overcome the problems of the prior art such as the limited non-contact optical path and low contact accuracy, and to achieve high-precision measurement of minute angular deformations of the mounting surface of the inertial device of the inertial measurement device, and to provide a measurement technology basis for structural optimization and system error compensation.

[0005] In order to meet the requirement of quantitatively determining the minute deformation of the installation surface of high-precision inertial devices in an inertial measurement unit, it is necessary to design a method for simulating and determining the force and thermal deformation of the inertial measurement unit. This method can obtain the influence of the thermal field on the force field of the inertial measurement unit, and can propose a reasonable fitting method for the installation surface of the inertial device caused by irregular heat, and specifically analyze the angular deformation value of the fitting surface relative to the original position in the coordinate system, so as to quantitatively express the angular deformation of the installation surface of the inertial device, and provide a method for determining the stability of the high-precision installation surface to improve the accuracy of the inertial navigation system through structural optimization design and system error compensation.

[0006] The technical solution provided by this application is as follows:

[0007] A method for simulating and determining the force and thermal deformation of an inertial measurement unit, comprising:

[0008] (1) For an inertial measurement unit, use the structural thermodynamics simulation method to calculate the overall structural deformation information caused by heat;

[0009] (2) Extract the original spatial position information of the discrete nodes at the target position of the inertial measurement unit; and according to the overall structural deformation information caused by heat, extract the three-dimensional change amount of the discrete nodes on the installation surface caused by heat; according to the original spatial position information of the discrete nodes and the three-dimensional change amount of the discrete nodes, calculate the spatial coordinates of the deformed discrete nodes;

[0010] (3) According to the spatial coordinates of the deformed discrete nodes, use the least squares spatial surface fitting method to obtain the spatial surface equation formed by the deformed discrete nodes and its fitting surface normal vector;

[0011] (4) Obtain the minute angular deformation of the high-precision inertial device of the inertial measurement unit caused by heat according to the included angle between the fitting surface normal vector and the vectors of the relevant coordinate system.

[0012] Furthermore, using the structural thermodynamics simulation method to calculate the overall structural deformation information caused by heat includes:

[0013] Based on the finite element method, calculate the thermal field distribution of the inertial measurement unit and the structural deformation caused by heat, specifically including:

[0014] According to the heat source distribution of the inertial measurement unit, set the boundary conditions for thermal field analysis to obtain the thermal field distribution information when the heat exchange of the inertial measurement unit is stable;

[0015] Import the thermal field distribution information as the initial condition into the force field calculation, and apply the mechanical boundary constraint conditions of the inertial measurement unit to calculate the structural deformation information caused by heat.

[0016] Furthermore, the implementation method of the spatial coordinates of the deformed discrete nodes in step (2) is:

[0017] Taking the installation surface of the high-precision inertial devices of the inertial measurement unit as the analysis object, the original spatial position information of all discrete nodes on the installation surface and the deformation amounts of each discrete node in the three coordinate directions of X, Y, and Z are extracted. By performing algebraic summation of the corresponding coordinates of the discrete nodes (i.e., the sum of the original spatial position information and the deformation amounts), the spatial coordinates of the discrete nodes on the installation surface caused by heat (i.e., the spatial coordinates of the deformed discrete nodes) can be obtained.

[0018] Further, the implementation method of obtaining the spatial plane equation and its normal vector formed by the deformed discrete nodes by using the least-squares spatial plane fitting method in step (3) is as follows:

[0019] The general equation expression of the fitting plane is:

[0020] Ax + By + Cz + D = 0 (C ≠ 0)

[0021] Where, A is the coefficient of x in the general equation of the discrete point fitting plane, B is the coefficient of y in the general equation of the discrete point fitting plane, C is the coefficient of z in the general equation of the discrete point fitting plane, and D is the constant of the general equation of the discrete point fitting plane;

[0022] That is:

[0023]

[0024] Denote:

[0025]

[0026] Substitute the above formula into The following formula can be obtained:

[0027] z = a 0 x + a 1 y + a 2

[0028] For the n discrete nodes on the installation surface of the high-precision inertial devices of the inertial measurement unit, they can be expressed as (x i , y i , z i ), i = 0, 1, 2, …… n - 1. To make the n discrete nodes fit the plane equation, that is:

[0029]

[0030] To make S minimum, take the partial derivatives of the above formula with respect to a 0 , a 1 , a 2 and set the partial derivatives to zero. That is:

[0031]

[0032] It is represented in matrix form as follows:

[0033]

[0034] By solving the above equation, the parameter a can be obtained. 0 , a 1 , a 2 , substituting into the formula z = a 0 x + a 1 y + a 2 , the fitting plane equation of the installation surface of the high-precision inertial device of the inertial measurement device can be obtained.

[0035] Then the normal vector of the fitting surface is

[0036] Furthermore, in step (4), the implementation method of obtaining the small angular deformation (the small angular deformation refers to the deformation with a deformation amount not greater than 50 arcseconds) of the high-precision inertial device of the inertial measurement device caused by heat according to the included angle between the normal vector of the fitting surface and the vector of the relevant coordinate system is as follows:

[0037] The small angular deformation of the inertial measurement device is characterized by the included angle between the fitting plane and the coordinate system plane, and can be converted into the included angle between the normal vector of the fitting plane and the unit vector of the coordinate system plane.

[0038] Then the calculation method of the angular deformation α of the fitting plane is as follows:

[0039]

[0040] where the unit of α is arcsecond; is the normal vector of the fitting plane, is the unit normal vector of the three planes of the coordinate system. When, it is the normal vector of the XY plane of the coordinate system, When, it is the normal vector of the YZ plane of the coordinate system; When, it is the normal vector of the XZ plane of the coordinate system.

[0041] Furthermore, when the initial positions of the installation surfaces of the high-precision inertial devices of the inertial measurement device are different, the angular deformations of their fitting planes relative to the coordinate system planes are also different. The specific calculation method is as follows:

[0042] When the initial position of the installation surface of the high-precision inertial device of the inertial measurement device is parallel to the YZ plane, in the above formula Take The angular deformation of the fitting plane around the coordinate axis Y (i.e., the change in the included angle between the fitting surface and the XY plane) can be obtained. Take The angular deformation of the fitting plane around the coordinate axis Z (i.e., the change in the included angle between the fitting surface and the XZ plane) can be obtained.

[0043] When the initial position of the mounting surface of the high-precision inertial device of the inertial measurement device is parallel to the XZ plane, in the above formula Taking the angular deformation of the fitting plane about the coordinate axis X can be obtained (i.e., the change in the angle between the fitting plane and the XY plane), Taking the angular deformation of the fitting plane about the coordinate axis Z can be obtained (i.e., the change in the angle between the fitting plane and the YZ plane);

[0044] When the initial position of the mounting surface of the high-precision inertial device of the inertial measurement device is parallel to the XY plane, in the above formula Taking the angular deformation of the fitting plane about the coordinate axis X can be obtained (i.e., the change in the angle between the fitting plane and the XZ plane), Taking the angular deformation of the fitting plane about the coordinate axis Y can be obtained (i.e., the change in the angle between the fitting plane and the YZ plane).

[0045] A computer program product includes a computer program / instructions, and when the computer program / instructions are executed by a processor, the steps of any one of the above-mentioned methods for simulating and determining the thermal deformation of an inertial measurement device are implemented.

[0046] The present invention has the following beneficial effects compared with the prior art:

[0047] (1) Based on the thermodynamic simulation method, the present invention calculates the overall structural deformation of the inertial measurement device when affected by the thermal field, overcomes the limitations of traditional contact strain gauge measurement and non-contact optical measurement tests and the limitation of low measurement accuracy, and obtains more comprehensive structural thermal deformation information;

[0048] (2) The present invention extracts the initial position information and deformation amount information of the mounting surface to calculate the spatial coordinates of the discrete nodes on the mounting surface caused by heat, and can calculate all the discrete node information on all the mounting surfaces in the device at one time, which is more efficient than experimental testing;

[0049] (3) The present invention uses the least squares method to fit the complex spatial surface after deformation, which can more accurately reflect the spatial position characteristics of the deformed surface than the traditional three-point fitting plane method;

[0050] (4) The present invention calculates the small angular deformation of the deformed surface in three spatial directions by using the angle between the fitting plane and the coordinate system axis. By decomposition, the change amount of the mounting surface in different directions can be obtained, and the influence of the deformed mounting surface on the sensitive axis of the inertial device can be obtained more clearly, providing accurate data basis for subsequent adjustment of the structural design scheme and system error compensation. Description of the Drawings

[0051] Figure 1Flow chart of a method for simulating and measuring the force and thermal deformation of an inertial measurement device according to the present invention;

[0052] Figure 2 Schematic diagram of the thermodynamics simulation method of the inertial measurement device according to the embodiment of the present invention;

[0053] Figure 3 Deformation nephogram of the installation surface of the high-precision inertial device of the inertial measurement device according to the embodiment of the present invention (taking the YZ installation surface as an example);

[0054] Figure 4 Position coordinates of discrete nodes after deformation of the installation surface of the inertial device and the fitting plane according to the embodiment of the present invention;

[0055] Figure 5 Angular deformation position relationship between the fitting surface and the coordinate axis according to the embodiment of the present invention.

[0056] Explanation of the reference numerals in the attached drawings: 1, base body; 2, bottom surface for installing high-precision inertial device; 3, installation base for high-precision inertial device; 4, high-precision inertial device; 5 - YZ installation surface; 6 - XZ installation surface; 7 - XY installation surface. Specific implementation manners

[0057] To make the objectives, technical solutions, and advantages of the present invention clearer, the following will further describe in detail the disclosed embodiments of the present invention in conjunction with the accompanying drawings.

[0058] This embodiment discloses a method for simulating and measuring the force and thermal deformation of an inertial measurement device. This method is used to simulate and measure the structural force and thermal deformation of the inertial measurement device. The inertial measurement device includes a base body 1, an installation base 3 for a high-precision inertial device, and three high-precision inertial devices 4. The base body 1 has a bottom surface 2 for installing a high-precision inertial device. The installation base 2 for a high-precision inertial device is installed on the bottom surface 2 for installing a high-precision inertial device. The installation base 2 for a high-precision inertial device has a YZ installation surface 5, an XZ installation surface 6, and an XY installation surface 7. The YZ installation surface 5, the XZ installation surface 6, and the XY installation surface 7 are all used to install a high-precision inertial device 4.

[0059] The method includes the following steps:

[0060] (1) Use the structural thermodynamics simulation method to calculate the temperature field distribution of the base body 1, the installation base 3 for a high-precision inertial device, and the high-precision inertial device 4 in a thermal field environment, and then conduct a force field deformation analysis to obtain the deformation result information of the overall structure;

[0061] (2) Calculate the spatial coordinates of the discrete nodes after deformation by extracting the original spatial position information of the discrete nodes on the three surfaces of the installation base 3 for a high-precision inertial device and the three-dimensional change amount of the discrete nodes caused by heat;

[0062] (3) The least - squares spatial plane fitting method is used to obtain the spatial plane equation and its normal vector formed by the discrete nodes after deformation. In the example, the spatial plane fitting of discrete nodes is performed on the YZ mounting surface, XZ mounting surface, and XY mounting surface respectively.

[0063] (4) According to the angles between the fitting plane normal vector and the vectors of the relevant coordinate systems, the small angular deformations of the high - precision inertial devices of the inertial measurement unit caused by heat are obtained. In the example, the small angular deformations around the coordinate axes at three different spatial positions can be obtained.

[0064] In the example, the implementation method of step (1) is as follows:

[0065] As Figure 2 shown, the thermo - mechanical coupling simulation calculation method is adopted. The thermal field information is given as the initial temperature condition to the mechanical calculation module, and discretization processing, material assignment, boundary condition application, calculation setting of the inertial device mounting surface, etc. are carried out on the mechanical calculation module model.

[0066] In the above example, key parts of the inertial measurement unit are selected to carry out the high - precision simulation measurement method, including the base 1, the bottom surface 2 for mounting the high - precision inertial device, the mounting base 3 for the high - precision inertial device, and the high - precision inertial device 4. For the convenience of subsequent analysis, Figure 2 the coordinate system and the YZ mounting surface 5, XZ mounting surface 6, and XY mounting surface 7 are also marked;

[0067] In the simulation method, different materials are first assigned to the structure, then each structure body is discretized according to the calculation requirements, and the thermal field condition is loaded onto the model as the initial temperature information of the geometric model. By setting the target results in the result requirements, the deformation information of the overall structure can be obtained.

[0068] In the example, the implementation method of step (2) is as follows:

[0069] As Figure 2 shown, the deformation calculations of the high - precision inertial device mounting surface in the X, Y, and Z directions are set, and the nephogram is obtained through simulation calculation;

[0070] The spatial position information of the discrete nodes on each nephogram and the deformation amounts in the X, Y, and Z directions are extracted, and through algebraic calculation, the position coordinates of each discrete node on the inertial device mounting surface in the thermal field environment can be obtained. As shown in Table 1, since there is a large amount of discrete node data, only some values are listed to represent the calculation relationship.

[0071] Table 1 Coordinate solution of discrete nodes on the mounting surface (taking the YZ plane as an example)

[0072]

[0073]

[0074] The implementation method of step (3) in the example is as follows:

[0075] Using spatial surface drawing software, draw the topographies of the YZ mounting surface, XZ mounting surface, and XY mounting surface in three-dimensional space, as Figure 4 shown;

[0076] Using the following method of fitting a plane by the least squares method, respectively fit the spatial planes of the deformed YZ mounting surface, XZ mounting surface, and XY mounting surface, as Figure 5 shown;

[0077] The general equation expression of the fitted plane is:

[0078] Ax + By + Cz + D = 0 (C ≠ 0)

[0079] That is:

[0080]

[0081] Denote:

[0082]

[0083] Substitute the above formula into The following formula can be obtained:

[0084] z = a 0 x + a 1 y + a 2

[0085] For the n discrete nodes on the high-precision inertial device mounting surface of the inertial measurement device, it can be expressed as (x i , y i , z i ), i = 0, 1, 2,..., n - 1. To make the n discrete nodes fit the plane equation, that is:

[0086]

[0087] To make S minimum, take the partial derivatives of the above formula with respect to a 0 , a 1 , a 2 and set the partial derivatives to zero. That is:

[0088]

[0089] It is represented in matrix form as follows:

[0090]

[0091] Solve the above equation to obtain the parameters a 0 , a1 , a 2 , substitute the formula z = a 0 x + a 1 y + a 2 , and the fitting plane equation of the installation surface of the high-precision inertial device of the inertial measurement device can be obtained. The following are the fitting equations of the YZ installation surface, XZ installation surface, and XY installation surface respectively:

[0092] YZ installation surface: -1.06037e6 * x - 0.32978 * y - z + 4.55963e7 = 0;

[0093] XZ installation surface: 2.1303 * x - 3.44087e-6 * y - z + 5.16225e6 = 0;

[0094] XY installation surface: 1.45105e-7 * x + 1.3225e-7 * Y - Z + 47.50035 = 0.

[0095] The implementation method of step (4) in the example is as follows:

[0096] The normal vectors of each plane can be extracted from the equations of the fitting planes of the above installation surfaces, which are respectively:

[0097] YZ installation surface:

[0098] XZ installation surface:

[0099] XY installation surface:

[0100] Then, according to the above calculation expressions of the deformation of each installation surface in a high-precision simulation determination method for the structure force and heat of an inertial measurement device of the present invention:

[0101] The calculation method of the angular deformation α of the fitting plane is as follows:

[0102]

[0103] Among them, the unit of α is arcsecond; is the normal vector of the fitting plane, is the unit normal vector of the three planes of the coordinate system.

[0104] Furthermore, the initial positions of the installation surfaces of the high-precision inertial devices of the inertial measurement device are different, and the angular deformations of their fitting planes relative to the coordinate system planes are also different. The specific calculation method is as follows:

[0105] When the initial position of the installation surface of the high-precision inertial device of the inertial measurement device is parallel to the YZ plane, in the above formula take The angular deformation of the fitted plane about the Y axis can be obtained. Take The angular deformation of the fitted plane about the Z axis can be obtained;

[0106] When the initial position of the mounting surface of the high-precision inertial device of the inertial measurement device is parallel to the XZ plane, in the above formula Take The angular deformation of the fitted plane about the X axis can be obtained, Take The angular deformation of the fitted plane about the Z axis can be obtained;

[0107] When the initial position of the mounting surface of the high-precision inertial device of the inertial measurement device is parallel to the XY plane, in the above formula Take The angular deformation of the fitted plane about the X axis can be obtained, Take The angular deformation of the fitted plane about the Y axis can be obtained.

[0108] From the above calculation method, the small angular deformations of the YZ mounting surface, XZ mounting surface, and XY mounting surface of the high-precision inertial device in the coordinate system direction can be obtained, as shown in Table 2:

[0109] Table 2 Angular Deformations of the Inertial Device Mounting Surface

[0110]

[0111]

[0112] The present invention has been described in detail above in combination with specific embodiments and exemplary examples. However, these descriptions should not be construed as limiting the present invention. Those skilled in the art understand that without departing from the spirit and scope of the present invention, various equivalent substitutions, modifications, or improvements can be made to the technical solutions and implementation manners of the present invention, and these all fall within the scope of the present invention. The protection scope of the present invention is subject to the appended claims.

[0113] The content not described in detail in the specification of the present application belongs to the well-known technology of those skilled in the art.

[0114] The present application has been described in detail above in combination with specific embodiments and exemplary examples. However, these descriptions should not be construed as limiting the present application. Those skilled in the art understand that without departing from the spirit and scope of the present application, various equivalent substitutions, modifications, or improvements can be made to the technical solutions and implementation manners of the present application, and these all fall within the scope of the present application. The protection scope of the present application is subject to the appended claims.

Claims

1. A method for measuring the mechanical and thermal deformation of an inertial measurement device, characterized in that: include: S1: For the inertial measurement unit, the structural thermodynamics simulation method is used to calculate the overall structural deformation information caused by heat; S2: extracting the original spatial position information of discrete nodes on a mounting surface of the inertial measurement device; and extracting the three-dimensional change of the discrete nodes on the mounting surface caused by heat according to the overall structural deformation information caused by heat; According to the original spatial position information of the discrete nodes and the three-dimensional change of the discrete nodes, the spatial coordinates of the discrete nodes after deformation are calculated; S3: According to the spatial coordinates of the discrete nodes after deformation, the least squares spatial surface fitting method is used to obtain the spatial surface equation composed of the discrete nodes after deformation and its fitting surface normal vector; S4: The small angular deformation of the fitting surface is obtained according to the angle between the normal vector of the fitting surface and the vector of the relevant coordinate system.

2. The method for measuring the mechanical and thermal deformation simulation of an inertial measurement device according to claim 1, characterized in that: In S1, a structural thermodynamics simulation method is used to calculate the overall deformation information of the structure caused by heat, including: According to the heat source distribution of the inertial measurement device, the boundary conditions of the thermal field analysis are set to obtain the thermal field distribution information when the heat exchange of the inertial measurement device is stable; The thermal field distribution information is imported into the force field calculation as the initial condition, and the mechanical boundary constraints of the inertial measurement device are applied to calculate the structural deformation information caused by heat.

3. The method for measuring mechanical and thermal deformation simulation of an inertial measurement device according to claim 1, characterized in that: In S2, the spatial coordinates of the discrete nodes after deformation are the sum of the original spatial position information of the discrete nodes on the installation surface and the three-dimensional variation of the discrete nodes on the installation surface.

4. The method for measuring the mechanical and thermal deformation simulation of an inertial measurement device according to claim 1, characterized in that: In S3, according to the spatial coordinates of the discrete nodes after deformation, the least squares spatial surface fitting method is used to obtain the spatial surface equation composed of the discrete nodes after deformation and the fitting surface normal vector thereof, including: The n discrete nodes on the mounting surface are represented by (x i ,y i ,z i ), i = 0, 1, 2, ... n-1, so that the n discrete nodes fit the plane equation, even if: Take partial derivatives of both sides of the above equation with respect to a0, a1, a2, and set the partial derivatives to zero, solve the final equation, obtain the parameters a0, a1, a2, substitute them into the equation z=a0x+a1y+a2, and obtain the fitting plane equation of the installation surface; From the fitting plane equation, the normal vector of the fitting surface can be obtained as 5. The method for measuring the mechanical and thermal deformation simulation of an inertial measurement device according to claim 1, characterized in that: In S4, the slight angular deformation of the fitting surface is obtained according to the angle between the normal vector of the fitting surface and the vector of the relevant coordinate system, including: The angular deformation α of the fitting surface is: Where α is in arc seconds; is the normal vector of the fitted surface, is the unit normal vector of the three planes of the coordinate system, i = xy, yz or xz, When , is the normal vector of the XY plane of the coordinate system, When , it is the normal vector of the YZ plane of the coordinate system; , is the normal vector of the XZ plane of the coordinate system.

6. The method for measuring mechanical and thermal deformation simulation of an inertial measurement device according to claim 5, characterized in that: When the initial position of the mounting surface of the high-precision inertial device of the inertial measurement device is parallel to the YZ plane, Pick The angular deformation of the fitting plane around the coordinate axis Y can be obtained. Pick The angular deformation of the fitting plane around the coordinate axis Z can be obtained.

7. The method for measuring mechanical and thermal deformation simulation of an inertial measurement device according to claim 5, characterized in that: When the initial position of the mounting surface of the high-precision inertial device of the inertial measurement device is parallel to the XZ plane, Pick The angular deformation of the fitting plane around the coordinate axis X can be obtained. Pick The angular deformation of the fitting plane around the coordinate axis Z can be obtained.

8. The method for measuring mechanical and thermal deformation simulation of an inertial measurement device according to claim 5, characterized in that: When the initial position of the mounting surface of the high-precision inertial device of the inertial measurement device is parallel to the XY plane, Pick The angular deformation of the fitting plane around the coordinate axis X can be obtained. Pick The angular deformation of the fitting plane around the coordinate axis Y can be obtained.

9. The method for measuring the mechanical and thermal deformation simulation of an inertial measurement device according to claim 5, characterized in that: Also includes: S5: The inertial measurement device has three mounting surfaces, which are a YZ mounting surface, an XZ mounting surface and an XY mounting surface. Steps S2-S4 are repeated to obtain small angular deformations of the fitting surfaces corresponding to the three mounting surfaces.

10. A computer program product comprising a computer program / instructions, characterized in that When the computer program / instruction is executed by a processor, the steps of the method for measuring mechanical and thermal deformation simulation of an inertial measurement device as described in any one of claims 1-9 are implemented.

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