Simulation modeling and on-orbit star sensor calibration method based on eddy current displacement sensor

Abstract

The invention provides a simulation modeling and on-orbit star sensor calibration method based on an eddy current displacement sensor. The method comprises the following steps: acquiring installation parameters of the eddy current displacement sensor and a relative motion relation between a satellite platform and a load platform; determining an eddy current measurement vector of the eddy current displacement sensor according to the installation parameters and the relative motion relation; for each dimension of the load platform, the following steps are executed: according to the installation parameter and the eddy current measurement vector of each eddy current displacement sensor on the dimension, the relative attitude deviation and the relative displacement deviation of the satellite platform are calculated; wherein each dimension is provided with four eddy current displacement sensors; and calibrating the load platform star sensor according to the relative attitude deviation, the relative displacement deviation and the obtained installation error matrix of the load platform star sensor. According to the scheme, the eddy current displacement sensor is utilized to realize the establishment of a simulation system and the calibration of the star sensor of the on-orbit load platform, so that the measurement precision is improved.

Description

Technical Field

[0001] The present invention relates to the field of satellite control technology, in particular to the field of satellite simulation verification technology, and in particular to a simulation modeling based on an eddy current displacement sensor and an on-orbit satellite sensor calibration method. Background Art

[0002] In recent years, with the demand for high resolution and ultra-wide coverage of space target measurement and imaging tasks, higher requirements have been put forward for the dynamic control stability of complex connected multi-body satellites with large loads and high dynamics. The high-speed rotating large load platform and the satellite platform form a complex connected multi-body system consisting of a star body, a rotating joint subsystem, and a load. The rotating joint subsystem is connected by a magnetic bearing joint, which is a six-degree-of-freedom joint system. In this satellite system, the load platform is controlled by multiple degrees of freedom relative to the satellite platform by utilizing the working principle of magnetic levitation, and it has strong anti-interference ability and high reliability; the non-contact eddy current displacement sensor in the magnetic bearing joint is used to obtain high accuracy and measurement precision.

[0003] Star sensors are important components in spacecraft. In order to ensure the accuracy of high-precision measurement and navigation, spacecraft star sensors need to be calibrated. The existing calibration method has low measurement accuracy and does not meet the higher requirements for dynamic control stability. Therefore, it is urgent to provide a simulation modeling and on-orbit star sensor calibration method based on eddy current displacement sensor. Summary of the invention

[0004] The present invention provides a simulation modeling and on-orbit star sensor calibration method based on eddy current displacement sensors, and uses eddy current displacement sensors to realize the establishment of a simulation system and the calibration of the on-orbit load platform star sensor, thereby improving the measurement accuracy.

[0005] In a first aspect, the present invention provides a simulation modeling and on-orbit satellite sensor calibration method based on an eddy current displacement sensor, the method comprising:

[0006] Acquiring installation parameters of the eddy current displacement sensor and the relative motion relationship between the satellite platform and the load platform; the satellite platform and the load platform are connected via a magnetic levitation joint; the magnetic levitation joint includes the eddy current displacement sensor;

[0007] Determining an eddy current measurement vector of the eddy current displacement sensor according to the installation parameters and the relative motion relationship;

[0008] For each dimension of the payload platform, the following steps are performed: according to the installation parameters of each eddy current displacement sensor in the dimension and the eddy current measurement vector, a relative attitude deviation and a relative displacement deviation of the satellite platform are calculated; wherein four eddy current displacement sensors are arranged in each dimension;

[0009] The load platform star sensor is calibrated according to the relative attitude deviation, the relative displacement deviation and the acquired installation error matrix of the load platform star sensor.

[0010] In a second aspect, the present invention further provides a simulation modeling and on-orbit satellite sensor calibration device based on an eddy current displacement sensor, comprising:

[0011] An acquisition module, used for acquiring installation parameters of the eddy current displacement sensor and the relative motion relationship between the satellite platform and the load platform; the satellite platform and the load platform are connected through a magnetic levitation joint; the magnetic levitation joint includes the eddy current displacement sensor;

[0012] An eddy current measurement module, used to determine an eddy current measurement vector of the eddy current displacement sensor according to the installation parameters and the relative motion relationship;

[0013] A decoupling module is used to perform, for each dimension of the payload platform: calculating the relative attitude deviation and relative displacement deviation of the satellite platform according to the installation parameters of each eddy current displacement sensor in the dimension and the eddy current measurement vector; wherein four eddy current displacement sensors are provided in each dimension;

[0014] The calibration module is used to calibrate the load platform star sensor according to the relative attitude deviation, the relative displacement deviation and the acquired installation error matrix of the load platform star sensor.

[0015] In a third aspect, the present invention further provides a computing device, comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, it implements any of the above-mentioned simulation modeling based on eddy current displacement sensors and on-orbit satellite sensor calibration methods.

[0016] In a fourth aspect, the present invention further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed in a computer, the computer is caused to execute any of the above-mentioned simulation modeling based on eddy current displacement sensors and on-orbit satellite sensor calibration methods.

[0017] In a fifth aspect, an embodiment of the present invention further provides a computer program product, comprising computer instructions, which, when executed by a processor, implement the steps of the method described in any first aspect of this specification.

[0018] The present invention provides a simulation modeling and on-orbit star sensor calibration method based on an eddy current displacement sensor, which is applied to a satellite platform and a load platform connected by a magnetic levitation joint, and the magnetic levitation joint includes an eddy current displacement sensor. The method first determines the eddy current measurement vector of the eddy current displacement sensor through the installation parameters of the eddy current displacement sensor and the relative motion relationship between the satellite platform and the load platform, and uses the installation parameters of four eddy current displacement sensors set on each dimension of the load platform and the measured eddy current measurement vector to determine the relative attitude deviation and relative displacement deviation of the satellite platform, and finally uses the relative attitude deviation, relative displacement deviation and the installation error matrix of the load platform star sensor to realize the calibration of the load platform star sensor. In this way, the present invention not only uses the working principle of the eddy current measurement sensor to complete the dynamic modeling of the eddy current measurement sensor, but also realizes the deviation calculation of the relative posture, thereby realizing the on-orbit calibration of the star sensor, and using the eddy current displacement sensor with higher accuracy and measurement accuracy to further improve the measurement accuracy and navigation accuracy, while realizing ground calibration based on the installation error matrix to complete the final calibration of the load platform star sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 It is a flow chart of a simulation modeling method based on an eddy current displacement sensor and an on-orbit satellite sensor calibration method provided by an embodiment of the present invention;

[0021] Figure 2 It is a schematic diagram of the working principle of radial eddy current measurement provided by one embodiment of the present invention;

[0022] Figure 3 It is a schematic diagram of the working principle of axial eddy current measurement provided by one embodiment of the present invention;

[0023] Figure 4 It is a schematic diagram of relative posture position decoupling calculation within a radial measurement section provided by an embodiment of the present invention;

[0024] Figure 5 is a schematic diagram of the relationship between a load platform coordinate system and a load platform rotation coordinate system provided by an embodiment of the present invention;

[0025] Figure 6 is a hardware architecture diagram of a computing device provided by an embodiment of the present invention;

[0026] Figure 7It is a structural diagram of a simulation modeling and on-orbit satellite sensor calibration device based on an eddy current displacement sensor provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0028] Please refer to Figure 1 The embodiment of the present invention provides a simulation modeling method based on an eddy current displacement sensor and a calibration method of an on-orbit satellite sensor, including:

[0029] Step 100, obtaining installation parameters of the eddy current displacement sensor and the relative motion relationship between the satellite platform and the payload platform; the satellite platform and the payload platform are connected via a magnetic levitation joint; the magnetic levitation joint includes the eddy current displacement sensor;

[0030] Step 102, determining an eddy current measurement vector of the eddy current displacement sensor according to the installation parameters and the relative motion relationship;

[0031] Step 104, for each dimension of the payload platform, the following steps are performed: according to the installation parameters of each eddy current displacement sensor in the dimension and the eddy current measurement vector, the relative attitude deviation and relative displacement deviation of the satellite platform are calculated; wherein four eddy current displacement sensors are arranged in each dimension;

[0032] Step 106 , calibrating the payload platform star sensor according to the relative attitude deviation, the relative displacement deviation and the acquired installation error matrix of the payload platform star sensor.

[0033] In the present invention, in a satellite platform and a load platform connected by a magnetic levitation joint, an eddy current displacement sensor is included in the magnetic levitation joint. First, a three-dimensional model of the eddy current displacement sensor is constructed by the installation parameters of the eddy current displacement sensor and the relative motion relationship between the satellite platform and the load platform. Then, the eddy current measurement vector of the eddy current displacement sensor is determined based on the three-dimensional model, so as to use the installation parameters of the four eddy current displacement sensors set on each dimension of the load platform and the measured eddy current measurement vector to determine the relative attitude deviation and relative displacement deviation of the satellite platform. Finally, the relative attitude deviation, relative displacement deviation and the installation error matrix of the load platform star sensor are used to realize the calibration of the load platform star sensor. In this way, the present invention not only utilizes the working principle of the eddy current measurement sensor to complete the dynamic modeling of the eddy current measurement sensor, but also realizes the deviation calculation of the relative posture, thereby realizing the on-orbit calibration of the star sensor, and further improves the measurement accuracy and navigation accuracy by using the eddy current displacement sensor with higher accuracy and measurement precision. At the same time, ground calibration is realized based on the installation error matrix to complete the final calibration of the load platform star sensor.

[0034] Described below Figure 1 How the various steps are performed.

[0035] Specifically, the coordinate system in the present invention includes: a satellite platform coordinate system, a payload platform coordinate system, a payload platform orbit coordinate system and a payload platform rotation coordinate system:

[0036] In the satellite platform coordinate system, the origin OL is the mass center of the satellite platform, the Ox axis is along the longitudinal axis of the satellite body, pointing to the payload platform as the positive direction, the positive direction of the z axis points to the I quadrant of the spacecraft (pointing to the center of the earth when there is no attitude deviation), perpendicular to the longitudinal axis, and the y axis, x axis and z axis form a right-handed system;

[0037] In the payload platform coordinate system, the origin OU is the center of mass of the payload platform, the uox axis is along the longitudinal axis of the satellite body, the positive direction is facing away from the satellite platform, the positive direction of the uoz axis points to the I quadrant of the spacecraft (pointing to the center of the earth when there is no attitude deviation), perpendicular to the longitudinal axis, and the uoy axis, uox and uoz axes form a right-handed system;

[0038] In the payload platform orbit coordinate system, the origin Oi is the center of mass of the payload platform, the xi axis points to the direction of the satellite's movement, the zi axis points to the center of the earth, and the yi axis, xi, and zi form a right-handed system;

[0039] In the load platform rotating coordinate system, the origin OU is the center of mass of the load platform, which coincides with the load platform orbital coordinate system before rotation. The rotating coordinate system is the rotating coordinate system after the orbital coordinate system rotates around the rotation axis by an angle.

[0040] First, for step 100, the measured end of the eddy current displacement sensor is installed on the stator shaft of the satellite platform; the measuring end of the eddy current displacement sensor is installed on the rotor shaft of the load platform; the magnetic suspension joint includes a stator shaft and a rotor shaft;

[0041] The installation parameters include the first position vector r from the center of mass of the satellite platform to the measured end in the satellite platform coordinate system L_P , the second position vector r from the center of mass of the load platform to the measuring end in the load platform coordinate system U_Q +r I , the third position vector r from the center of mass of the satellite platform to the center of mass of the payload platform in the orbital system L_U , eddy current stator direction r in satellite platform coordinate system L_X , eddy current measurement rotor direction r in the load platform coordinate system U_X ;

[0042] The relative motion relationship includes: the transformation matrix C of the satellite platform coordinate system relative to the orbital system LO , the transformation matrix C of the load platform coordinate system relative to the track system UO .

[0043] It should be noted that the rotor of the magnetic bearing is installed on the rotor of the magnetic joint, and the rotor of the magnetic joint (i.e. the rotor shaft) is installed on the load platform; the stator of the magnetic bearing is installed on the stator of the joint (i.e. the stator shaft), and the stator of the joint is installed on the satellite platform. The working principle of the eddy current displacement sensor is to drive the magnetic field around the eddy current coil to change through a pulse current of a certain waveform, and generate eddy current at the induction point of the metal parts of the central bearing. Figure 2 In the schematic diagram of radial eddy current measurement working principle shown in FIG. 1 , the installation position of the eddy current displacement sensor is r U_X The direction of the rotor shaft parallel to the load platform, and the measurement direction is the load platform rotor shaft axis r U_X The vertical direction of the eddy current stator is related to the vector r L_X The direction is consistent. The vector direction is fixed in the satellite platform coordinate system. The direction is consistent and the vector size is ar L_X ; where a is the coefficient. The direction of the eddy current measurement rotor is related to r U_X The direction is consistent and is the fixed direction of this system.

[0044] In step 102, the radial eddy current measurement vector is determined by the following formula:

[0045]

[0046] Among them, r b is the radial eddy current measurement vector in the load platform coordinate system;

[0047] CUO is the transformation matrix of the load platform coordinate system relative to the track system, is the transposed matrix of the transformation matrix;

[0048] C LO is the transformation matrix of the satellite platform coordinate system relative to the orbital system, is the transposed matrix of the transformation matrix;

[0049] In the orbital system, r L_U is the third position vector from the center of mass of the satellite platform to the center of mass of the payload platform;

[0050] In the satellite platform coordinate system, r L_X is the direction of the stator axis; r L_P is the first position vector from the center of mass of the satellite platform to the measured end;

[0051] In the load platform coordinate system, r U_X is the direction of the rotor axis; r U_Q +r I is the second position vector from the center of mass of the load platform to the measuring end.

[0052] Specifically, Figure 2 As shown, the radial eddy current measurement vector r is uniformly expressed in the orbital system as follows:

[0053]

[0054] Because in Figure 2 In the same coordinate system, the radial eddy current measurement vector r and the eddy current installation direction r at a fixed position in the load platform coordinate system are U_X are mutually perpendicular vectors, so Considering the attitude motion of the satellite platform and the payload platform and the relative motion relationship between the platforms, the following expression for the coefficient a can be obtained:

[0055]

[0056] Substitute a into the above radial eddy current measurement vector r to obtain the radial eddy current measurement vector r in the load platform coordinate system. b :

[0057]

[0058] In the present invention, the relative attitude and relative position of the large inertia load platform need to be considered to ensure high measurement accuracy and high control accuracy of the satellite. It should be noted that the large inertia load is preferably such that the mass of the load platform itself is equivalent to the mass of the satellite platform.

[0059] In a preferred embodiment, Figure 3 In the schematic diagram of the axial eddy current measurement working principle shown in FIG, the installation position of the eddy current displacement sensor is perpendicular to the rotor axis of the load platform, and the measurement direction is parallel to the rotor axis of the load platform. Considering that the axial eddy current installation surface is perpendicular to the rotor axis, the measurement direction is consistent with the rotor axis. Since the eddy current is installed on the load platform coordinate system, the installation position vector in this system is expressed as r U_Q +r I From the eddy current measurement, it can be seen that the axial eddy current measurement vector r in the orbital system can be obtained by vector calculation. z :

[0060]

[0061] Because in Figure 3 In the axial eddy current measurement vector r z The central bearing metal part connected to the satellite platform L_X are mutually perpendicular vectors, so Considering the attitude motion of the satellite platform and the payload platform and the relative motion relationship between the platforms, the following expression for the coefficient b can be obtained:

[0062]

[0063] Substitute b into the above axial eddy current measurement vector r z The axial eddy current measurement vector r in the load platform coordinate system is obtained s :

[0064]

[0065] With respect to step 104, on the measurement section of each dimension, the eddy current displacement sensors are distributed on the upper eddy current surface and the lower eddy current surface, and two eddy current displacement sensors are centrally symmetrically installed on the upper eddy current surface and the lower eddy current surface;

[0066] According to the installation parameters of each eddy current displacement sensor in this dimension and the radial eddy current measurement vector, the relative attitude deviation and relative displacement deviation of the satellite platform are calculated, including:

[0067] The projection of the radial eddy current measurement vector within the measurement cross section of this dimension is taken as the relative distance;

[0068] According to the installation parameters, the displacement of each eddy current displacement sensor from the geometric center of the rotating shaft of the magnetic suspension joint in the positive direction is determined;

[0069] According to the relative distance and displacement of each eddy current displacement sensor, the relative attitude deviation and relative displacement deviation are calculated.

[0070] It should be noted that the magnetic levitation joint has three translational degrees of freedom, each of which corresponds to each dimension of the load platform, and four eddy current displacement sensors are installed in each dimension.

[0071] In a preferred embodiment, the relative posture deviation is determined by the following formula:

[0072]

[0073] The relative displacement deviation is determined by the following formula:

[0074]

[0075] Among them, θ is the relative posture deviation; P is the relative displacement deviation; d U_1 ,d U_2 are the relative distances between the first eddy current displacement sensor and the second eddy current displacement sensor on the upper eddy current surface within the measurement section; d D_1 ,d D_2 are the relative distances between the third eddy current displacement sensor and the fourth eddy current displacement sensor of the lower eddy current surface within the measurement section; L 1 L is the displacement of the eddy current displacement sensor located on the upper eddy current surface from the geometric center of the rotating axis of the magnetic levitation joint in the positive direction; 2 is the displacement of the eddy current displacement sensor located on the lower eddy current surface from the geometric center of the rotating shaft of the magnetic levitation joint in the positive direction; L is the displacement of the upper eddy current surface and the lower eddy current surface in the positive direction, L = L 1 -L 2 .

[0076] It should be noted that d U_1 ,d U_2 ,d D_1 ,d D_2 All are scalars.

[0077] Specifically, the relative position and relative attitude of the eddy current measurement vectors measured by the four eddy current displacement sensors in each dimension are decoupled and calculated, such as Figure 4 The eddy current data measurement situation within the radial measurement section shown in the figure, four eddy currents are installed as two upper and lower eddy current surfaces in the load platform coordinate system, and two eddy current displacement sensors are symmetrically installed at the center of each eddy current surface. The central bearing metal component fixed to the satellite platform in the nominal locked state is located at the center position of the eddy current measurement. After the lock is released, the load platform and the satellite platform produce relative position and posture changes. Among them, the first eddy current displacement sensor D1 and the second eddy current displacement sensor D2 on the upper eddy current surface, the third eddy current displacement sensor D3 and the fourth eddy current displacement sensor D4 on the lower eddy current surface. Ignoring small-order terms, the relative distance information measured by the four eddy current displacement sensors can decouple the calculation of the relative posture deviation θ and relative position deviation P of the satellite platform and the load platform. As Figure 4 As shown, the displacement of the eddy current displacement sensor located on the lower eddy current surface from the geometric center of the rotating axis of the magnetic levitation joint in the positive direction is -L 2 ; L = L 1 -(-L 2 ).

[0078] In step 106, the installation error matrix of the payload platform star sensor is obtained by the following method:

[0079] Get the attitude transformation matrix C of the payload platform relative to the satellite platform du ;

[0080] According to the first measurement input matrix C of the satellite platform's star sensor si_d and the first installation matrix C sb_d , the second measurement input matrix C of the star sensor of the payload platform si_u and the second installation matrix C sb_u And the attitude transformation matrix C du , calculate the installation error matrix;

[0081] Installation error matrix C Δ Determined by the following formula:

[0082]

[0083] Among them, C Δ is the installation error matrix; C du is the attitude transformation matrix; C si_d is the first measurement input matrix; C sb_d is the first installation matrix; C si_u is the second measurement input matrix; C sb_u For the second installation matrix.

[0084] Specifically, Figure 5 As shown, with the X axis as the rotation axis, A_Y and A_Z are the relative angles of the two axes that can be measured by eddy current. Considering the eddy current measurement characteristics, the attitude angle in the rolling direction uses the third-party measurement data, and the attitude conversion matrix of the payload platform relative to the satellite platform can be obtained as C du =dcm(A_X, A_Y, A_Z, 123); where dcm(a, b, c, 123) is a function description of the attitude conversion matrix calculated by the attitude angle in the 123 order, and dcm represents the direction cosine matrix. According to the first measurement output matrix C of the star sensor of the satellite platform si_d and the first installation matrix C sb_d , determine the attitude matrix of the satellite platform coordinate system relative to the inertial system: According to the second measurement output matrix C of the payload platform star sensor si_u and the second installation matrix Csb_u , determine the attitude matrix of the load platform coordinate system relative to the inertial system: Considering the time delay characteristics of the star sensor, the eddy current measurement is taken as the nominal time, and the star sensor data are extrapolated to the nominal time data. It should be noted that the superscript T represents the matrix transposition. The installation error matrix of the load platform star sensor is C Δ According to the above installation relationship, the following relationship is obtained:

[0085]

[0086] Therefore, the installation error matrix of the star sensor on the payload platform is obtained by the above reasoning:

[0087]

[0088] With respect to step 106, the payload platform star sensor is calibrated according to the relative attitude deviation, the relative displacement deviation and the acquired installation error matrix of the payload platform star sensor, including:

[0089] The star sensor of the payload platform is calibrated using the installation error matrix;

[0090] Acquire a first absolute attitude and a first absolute position of the satellite platform and a second absolute attitude and a second absolute position of the payload platform;

[0091] The first absolute attitude and the relative attitude deviation are summed to obtain the current second absolute attitude of the load platform;

[0092] The first absolute position and the relative displacement deviation are summed to obtain the current second absolute position of the load platform;

[0093] The current second absolute posture is adjusted to be the same as the second absolute posture, and the current second absolute position is adjusted to be the same as the second absolute position, so as to complete the installation and calibration of the star sensor of the on-orbit payload platform.

[0094] In the present invention, the ground calibration of the star sensor of the payload platform is realized by installing the error matrix, so as to ensure that its performance under ideal conditions can meet the design requirements. At the same time, by comparing the second absolute posture preset to be achieved by the payload platform with the current second absolute posture in real time, the posture of the payload platform is adjusted in real time; and by comparing the second absolute position preset to be achieved by the payload platform with the current second absolute position in real time, the position of the payload platform is adjusted in real time, so as to realize the on-orbit calibration of the star sensor of the payload platform based on the adjustment of the absolute posture and the absolute position, so as to ensure the measurement accuracy and stability of the star sensor in practical applications.

[0095] In the present invention, eddy current vector measurement is performed on an eddy current displacement sensor on a magnetic levitation joint connecting a satellite platform and a payload platform, and the relative attitude deviation and relative displacement deviation of the satellite platform are obtained by decoupling and calculating the eddy current measurement vector, so that the relative attitude deviation and relative displacement deviation obtained based on the high-reliability magnetic levitation joint and the high-accuracy and high-measurement-precision eddy current displacement sensor have higher reliability, higher accuracy and higher measurement precision, thereby significantly improving the measurement precision of the on-orbit payload platform star sensor calibrated based on the relative attitude deviation and relative displacement deviation, thereby improving the success rate of the entire space mission and the data accuracy.

[0096] like Figure 6 , Figure 7 As shown, the embodiment of the present invention provides a simulation modeling and on-orbit satellite sensor calibration device based on eddy current displacement sensor. The device embodiment can be implemented by software, or by hardware or a combination of software and hardware. From the hardware level, Figure 6 As shown in FIG. 1 , a hardware architecture diagram of a computing device where a simulation modeling and on-orbit satellite sensor calibration device based on an eddy current displacement sensor according to an embodiment of the present invention is located is shown in FIG. Figure 6 In addition to the processor, memory, network interface, and non-volatile memory shown in the figure, the computing device in which the device is located in the embodiment may also generally include other hardware, such as a forwarding chip responsible for processing messages, etc. Taking software implementation as an example, Figure 7 As shown, as a device in a logical sense, the CPU of the computing device in which it is located reads the corresponding computer program in the non-volatile memory into the memory and runs it. This embodiment provides a simulation modeling and on-orbit satellite sensor calibration device based on eddy current displacement sensor, including:

[0097] The acquisition module 700 is used to acquire the installation parameters of the eddy current displacement sensor and the relative motion relationship between the satellite platform and the load platform; the satellite platform and the load platform are connected through a magnetic levitation joint; the magnetic levitation joint includes the eddy current displacement sensor;

[0098] The eddy current measurement module 702 is used to determine the eddy current measurement vector of the eddy current displacement sensor according to the installation parameters and the relative motion relationship;

[0099] The decoupling module 704 is used to perform, for each dimension of the payload platform: calculating the relative attitude deviation and relative displacement deviation of the satellite platform according to the installation parameters of each eddy current displacement sensor and the eddy current measurement vector in the dimension; wherein four eddy current displacement sensors are arranged in each dimension;

[0100] The calibration module 706 is used to calibrate the payload platform star sensor according to the relative attitude deviation, the relative displacement deviation and the acquired installation error matrix of the payload platform star sensor.

[0101] In some specific implementations, the acquisition module 700 may be used to execute the above step 100 , the eddy current measurement module 702 may be used to execute the above step 102 , the decoupling module 704 may be used to execute the above step 104 , and the calibration module 706 may be used to execute the above step 106 .

[0102] In some specific implementations, the measured end of the eddy current displacement sensor is mounted on the stator shaft of the satellite platform; the measuring end of the eddy current displacement sensor is mounted on the rotor shaft of the load platform; the magnetic suspension joint includes a stator shaft and a rotor shaft;

[0103] The installation parameters include the first position vector r from the center of mass of the satellite platform to the measured end in the satellite platform coordinate system L_P , the second position vector r from the center of mass of the load platform to the measuring end in the load platform coordinate system U_Q +r I , the third position vector r from the center of mass of the satellite platform to the center of mass of the payload platform in the orbital system L_U , eddy current stator direction r in satellite platform coordinate system L_X , eddy current measurement rotor direction r in the load platform coordinate system U_X ;

[0104] The relative motion relationship includes: the transformation matrix C of the satellite platform coordinate system relative to the orbital system LO , the transformation matrix C of the load platform coordinate system relative to the track system UO .

[0105] In some specific implementations, in the eddy current measurement module 702,

[0106] The radial eddy current measurement vector is determined by the following formula:

[0107]

[0108] The axial eddy current measurement vector is determined by the following formula:

[0109]

[0110] Among them, r b is the radial eddy current measurement vector in the load platform coordinate system; r s is the axial eddy current measurement vector in the load platform coordinate system;

[0111] C UOis the transformation matrix of the load platform coordinate system relative to the track system, is the transposed matrix of the transformation matrix;

[0112] C LO is the transformation matrix of the satellite platform coordinate system relative to the orbital system, is the transposed matrix of the transformation matrix;

[0113] In the orbital system, r L_U is the third position vector from the center of mass of the satellite platform to the center of mass of the payload platform;

[0114] In the satellite platform coordinate system, r L_X is the direction of the stator axis; r L_P is the first position vector from the center of mass of the satellite platform to the measured end;

[0115] In the load platform coordinate system, r U_X is the direction of the rotor axis; r U_Q +r I is the second position vector from the center of mass of the load platform to the measuring end.

[0116] In some specific implementations, on the measurement section in each dimension, the eddy current displacement sensors are distributed on the upper eddy current surface and the lower eddy current surface, and two eddy current displacement sensors are centrally symmetrically installed on the upper eddy current surface and the lower eddy current surface.

[0117] In some specific implementations, the decoupling module 704 is further configured to perform the following operations:

[0118] The projection of the eddy current measurement vector within the measurement cross section of this dimension is taken as the relative distance;

[0119] According to the installation parameters, the displacement of each eddy current displacement sensor from the geometric center of the rotating shaft of the magnetic suspension joint in the positive direction is determined;

[0120] According to the relative distance and displacement of each eddy current displacement sensor, the relative attitude deviation and relative displacement deviation are calculated; the relative attitude deviation is determined by the following formula:

[0121]

[0122] The relative displacement deviation is determined by the following formula:

[0123]

[0124] Among them, θ is the relative posture deviation; P is the relative displacement deviation; d U_1 ,d U_2 are the relative distances between the first eddy current displacement sensor and the second eddy current displacement sensor on the upper eddy current surface within the measurement section; dD_1 ,d D_2 are the relative distances between the third eddy current displacement sensor and the fourth eddy current displacement sensor of the lower eddy current surface within the measurement section; L 1 L is the displacement of the eddy current displacement sensor located on the upper eddy current surface from the geometric center of the rotating axis of the magnetic levitation joint in the positive direction; 2 is the displacement of the eddy current displacement sensor located on the lower eddy current surface from the geometric center of the rotating shaft of the magnetic levitation joint in the positive direction; L is the displacement of the upper eddy current surface and the lower eddy current surface in the positive direction, L = L 1 -L 2 .

[0125] In some specific implementations, the installation error matrix of the payload platform star sensor is obtained by the following method:

[0126] Get the attitude transformation matrix C of the payload platform relative to the satellite platform du ;

[0127] According to the first measurement input matrix C of the satellite platform's star sensor si_d and the first installation matrix C sb_d , the second measurement input matrix C of the star sensor of the payload platform si_u and the second installation matrix C sb_u And the attitude transformation matrix C du , calculate the installation error matrix;

[0128] Installation error matrix C Δ Determined by the following formula:

[0129]

[0130] Among them, C Δ is the installation error matrix; C du is the attitude transformation matrix; C si_d is the first measurement input matrix; C sb_d is the first installation matrix; C si_u is the second measurement input matrix; C sb_u For the second installation matrix.

[0131] In some specific implementations, the calibration module 706 is further configured to perform the following operations:

[0132] The star sensor of the payload platform is calibrated using the installation error matrix;

[0133] Acquire a first absolute attitude and a first absolute position of the satellite platform and a second absolute attitude and a second absolute position of the payload platform;

[0134] The first absolute attitude and the relative attitude deviation are summed to obtain the current second absolute attitude of the load platform;

[0135] The first absolute position and the relative displacement deviation are summed to obtain the current second absolute position of the load platform;

[0136] The current second absolute posture is adjusted to be the same as the second absolute posture, and the current second absolute position is adjusted to be the same as the second absolute position, so as to complete the installation and calibration of the star sensor of the on-orbit payload platform.

[0137] It is understandable that the structure illustrated in the embodiment of the present invention does not constitute a specific limitation on a simulation modeling and on-orbit star sensor calibration device based on eddy current displacement sensors. In other embodiments of the present invention, a simulation modeling and on-orbit star sensor calibration device based on eddy current displacement sensors may include more or fewer components than shown in the figure, or combine some components, or split some components, or arrange the components differently. The components shown in the figure may be implemented in hardware, software, or a combination of software and hardware.

[0138] The information interaction, execution process and other contents between the modules in the above-mentioned device are based on the same concept as the embodiment of the method of the present invention. For the specific contents, please refer to the description in the embodiment of the method of the present invention, and no further description is given here.

[0139] An embodiment of the present invention further provides a computing device, including a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the simulation modeling based on the eddy current displacement sensor and the on-orbit satellite sensor calibration method in any embodiment of the present invention is implemented.

[0140] An embodiment of the present invention further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the processor executes the simulation modeling based on eddy current displacement sensor and the on-orbit satellite sensor calibration method in any embodiment of the present invention.

[0141] An embodiment of the present application also provides a computer program product, which includes a computer program. A processor of a computer device reads the computer program from a computer-readable storage medium, and the processor executes the computer program, so that the computer device executes the simulation modeling based on eddy current displacement sensor and the on-orbit satellite sensor calibration method described in any of the above embodiments.

[0142] Specifically, a system or device equipped with a storage medium can be provided, on which software program code that implements the functions of any of the above-mentioned embodiments is stored, and a computer (or CPU or MPU) of the system or device can be enabled to read and execute the program code stored in the storage medium.

[0143] In this case, the program code itself read from the storage medium can realize the function of any one of the above-mentioned embodiments, and thus the program code and the storage medium storing the program code constitute a part of the present invention.

[0144] The storage medium embodiments for providing the program code include a floppy disk, a hard disk, a magneto-optical disk, an optical disk (such as CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW, DVD+RW), a magnetic tape, a non-volatile memory card, and a ROM. Alternatively, the program code can be downloaded from a server computer by a communication network.

[0145] In addition, it should be clear that the functions of any of the above embodiments can be implemented not only by executing the program code read by the computer, but also by enabling an operating system operating on the computer to complete part or all of the actual operations based on instructions from the program code.

[0146] In addition, it can be understood that the program code read from the storage medium is written to a memory provided in an expansion board inserted into the computer or to a memory provided in an expansion module connected to the computer, and then based on the instructions of the program code, a CPU installed on the expansion board or expansion module is enabled to perform part or all of the actual operations, thereby realizing the functions of any of the above-mentioned embodiments.

[0147] It should be noted that, in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise a ..." do not exclude the presence of other identical factors in the process, method, article or device including the elements.

[0148] A person of ordinary skill in the art can understand that all or part of the steps of implementing the above method embodiments can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk, etc., various media that can store program codes.

[0149] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A simulation modeling method based on eddy current displacement sensor and a calibration method of on-orbit satellite sensor, characterized in that: include: Obtain the installation parameters of the eddy current displacement sensor and the relative motion relationship between the satellite platform and the payload platform; The satellite platform and the load platform are connected via a magnetic levitation joint; the magnetic levitation joint includes the eddy current displacement sensor; Determining an eddy current measurement vector of the eddy current displacement sensor according to the installation parameters and the relative motion relationship; For each dimension of the payload platform, the following steps are performed: according to the installation parameters of each eddy current displacement sensor in the dimension and the eddy current measurement vector, a relative attitude deviation and a relative displacement deviation of the satellite platform are calculated; wherein four eddy current displacement sensors are arranged in each dimension; The load platform star sensor is calibrated according to the relative attitude deviation, the relative displacement deviation and the acquired installation error matrix of the load platform star sensor.

2. The method according to claim 1, characterized in that The measured end of the eddy current displacement sensor is installed on the stator shaft of the satellite platform; the measuring end of the eddy current displacement sensor is installed on the rotor shaft of the load platform; the magnetic suspension joint includes a stator shaft and a rotor shaft; The installation parameters include a first position vector from the mass center of the satellite platform to the measured end, a second position vector from the mass center of the load platform to the measuring end, a third position vector from the mass center of the satellite platform to the mass center of the load platform, an eddy current stator direction, and an eddy current measurement rotor direction; The relative motion relationship includes: a transformation matrix of the satellite platform coordinate system of the satellite platform relative to the orbital system, and a transformation matrix of the payload platform coordinate system of the payload platform relative to the orbital system.

3. The method according to claim 2, characterized in that The eddy current measurement vector includes a radial eddy current measurement vector and an axial eddy current measurement vector; The radial eddy current measurement vector is determined by the following formula: The axial eddy current measurement vector is determined by the following formula: Among them, r b is the radial eddy current measurement vector in the load platform coordinate system; r s is the axial eddy current measurement vector in the load platform coordinate system; a and b are coefficients; C UO is the transformation matrix of the load platform coordinate system of the load platform relative to the track system, is the transposed matrix of the transformation matrix; C LO is the transformation matrix of the satellite platform coordinate system of the satellite platform relative to the orbital system, is the transposed matrix of the transformation matrix; In the orbital system, r L_U A third position vector from the center of mass of the satellite platform to the center of mass of the payload platform; In the satellite platform coordinate system, r L_X is the direction of the stator axis; r L_P is a first position vector from the center of mass of the satellite platform to the measured end; In the load platform coordinate system, r U_X is the direction of the rotor axis; r U_Q +r I is a second position vector from the center of mass of the load platform to the measuring end.

4. The method according to claim 1, characterized in that: On the measurement section of each dimension, the eddy current displacement sensors are distributed on the upper eddy current surface and the lower eddy current surface, and two eddy current displacement sensors are centrally symmetrically installed on the upper eddy current surface and the lower eddy current surface; The step of calculating the relative attitude deviation and relative displacement deviation of the satellite platform according to the installation parameters of each eddy current displacement sensor in the dimension and the eddy current measurement vector comprises: Taking the projection of the eddy current measurement vector within the measurement cross section of the dimension as the relative distance; Determine the displacement of each eddy current displacement sensor from the geometric center of the rotating shaft of the magnetic levitation joint in the positive direction according to the installation parameters; The relative posture deviation and the relative displacement deviation are calculated according to the relative distance and the displacement of each eddy current displacement sensor.

5. The method according to claim 4, characterized in that The relative posture deviation is determined by the following formula: The relative displacement deviation is determined by the following formula: Wherein, θ is the relative posture deviation; P is the relative displacement deviation; d U_1 ,d U_2 are the relative distances between the first eddy current displacement sensor and the second eddy current displacement sensor on the upper eddy current surface within the measurement section; d D_1 ,d D_2 are the relative distances between the third eddy current displacement sensor and the fourth eddy current displacement sensor of the lower eddy current surface within the measuring section; L1 is the displacement of the eddy current displacement sensor located on the upper eddy current surface from the geometric center of the rotating shaft of the magnetic levitation joint in the positive direction; L2 is the displacement of the eddy current displacement sensor located on the lower eddy current surface from the geometric center of the rotating shaft of the magnetic levitation joint in the positive direction; L is the displacement of the upper eddy current surface and the lower eddy current surface in the positive direction, L=L1-L2.

6. The method according to claim 1, characterized in that The installation error matrix of the payload platform star sensor is obtained by the following method: Acquire an attitude conversion matrix of the payload platform relative to the satellite platform; The installation error matrix is ​​calculated based on the first measurement output matrix and the first installation matrix of the star sensor of the satellite platform, the second measurement output matrix and the second installation matrix of the star sensor of the payload platform, and the attitude conversion matrix; The installation error matrix is ​​determined by the following formula: Among them, C Δ is the installation error matrix; C du is the posture transformation matrix; C si_d is the first measurement input matrix; C sb_d is the first installation matrix; C si_u is the second measurement input matrix; C sb_u For the second installation matrix.

7. The method according to any one of claims 1 to 6, characterized in that: The calibrating the load platform star sensor according to the relative attitude deviation, the relative displacement deviation and the acquired installation error matrix of the load platform star sensor comprises: Calibrate the payload platform star sensor using the installation error matrix; Acquire a first absolute attitude and a first absolute position of the satellite platform and a second absolute attitude and a second absolute position of the payload platform; Summing the first absolute posture and the relative posture deviation to obtain a current second absolute posture of the load platform; Summing the first absolute position and the relative displacement deviation to obtain a current second absolute position of the load platform; The current second absolute posture is adjusted to be the same as the second absolute posture, and the current second absolute position is adjusted to be the same as the second absolute position, so as to complete the installation calibration of the on-orbit payload platform star sensor.

8. A simulation modeling and on-orbit satellite sensor calibration device based on eddy current displacement sensor, characterized in that: include: An acquisition module, used for acquiring installation parameters of the eddy current displacement sensor and the relative motion relationship between the satellite platform and the load platform; the satellite platform and the load platform are connected through a magnetic levitation joint; the magnetic levitation joint includes the eddy current displacement sensor; An eddy current measurement module, used to determine an eddy current measurement vector of the eddy current displacement sensor according to the installation parameters and the relative motion relationship; A decoupling module is used to perform, for each dimension of the payload platform: calculating the relative attitude deviation and relative displacement deviation of the satellite platform according to the installation parameters of each eddy current displacement sensor in the dimension and the eddy current measurement vector; wherein four eddy current displacement sensors are provided in each dimension; The calibration module is used to calibrate the load platform star sensor according to the relative attitude deviation, the relative displacement deviation and the acquired installation error matrix of the load platform star sensor.

9. A computing device, comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the method according to any one of claims 1 to 7 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, causes the computer to execute the method according to any one of claims 1 to 7.

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