A method for modeling complex connected multi-body dynamics with large inertia rotating loads

Abstract

The present invention provides a complex connection multi-body dynamic modeling method for a large inertia rotating load, which relates to the technical field of spacecraft dynamic modeling, and is applied to satellites in which both the satellite platform and the payload platform are large inertia rigid bodies, including: establishing a reference coordinate system for the satellite; obtaining the position vector and angular velocity vector of the satellite platform and the payload platform according to the reference coordinate system; establishing the angular momentum moment equation of the satellite relative to the center of mass of the satellite, the momentum moment equation of the payload platform relative to the connection point, the center of mass translation equation of the satellite, and the center of mass translation equation of the payload platform according to the position vector, the angular velocity vector, the mass of the satellite platform, and the mass of the payload platform. This scheme realizes the dynamic modeling of a complex connection multi-body satellite with a large inertia rotating load.

Description

Technical Field

[0001] The invention relates to the technical field of spacecraft dynamics modeling, and in particular to a complex-connected multi-body dynamics modeling method for large-inertia rotating loads. Background Art

[0002] With the demand for high resolution and ultra-wide coverage in space imaging missions, the structure of satellite payloads is becoming more and more complex, showing a trend of large mass and large inertia. For a multi-body satellite consisting of a high-speed rotating large payload platform and a satellite platform, the mass characteristics of the payload platform carrying a large imaging payload and the satellite platform are equivalent, and the inertia of the payload platform is also equivalent to the inertia of the satellite platform. Therefore, the interference of the high dynamic motion characteristics of the large payload on the celestial body cannot be ignored, resulting in extremely complex system dynamics modeling. Therefore, it is urgent to provide a complex connection multi-body dynamics modeling method for large inertia rotating payloads. Summary of the invention

[0003] The invention provides a complex-connected multi-body dynamics modeling method for a large-inertia rotating load, thereby realizing the dynamics modeling of a complex-connected multi-body satellite for a large-inertia rotating load.

[0004] In a first aspect, the present invention provides a complex connection multi-body dynamics modeling method for a large inertia rotating load, which is applied to a satellite in which both a satellite platform and a load platform are large inertia rigid bodies, and the load platform and the satellite platform are connected through a connection point, comprising:

[0005] Establishing a reference coordinate system for the satellite;

[0006] Acquire the position vector and angular velocity vector of the satellite platform and the payload platform according to the reference coordinate system;

[0007] According to the position vector, the angular velocity vector, the mass of the satellite platform and the mass of the payload platform, an angular momentum equation of the satellite relative to the satellite center of mass, an angular momentum equation of the payload platform relative to the connection point, a center of mass translation equation of the satellite and a center of mass translation equation of the payload platform are established.

[0008] In a second aspect, the present invention further provides a complex connection multi-body dynamics modeling device for a large inertia rotating load, which is applied to a satellite in which both the satellite platform and the load platform are large inertia rigid bodies, comprising:

[0009] A coordinate establishment module, used to establish a reference coordinate system of the satellite;

[0010] A space pointing module, used for acquiring the position vector and angular velocity vector of the satellite platform and the payload platform according to the reference coordinate system;

[0011] The model building module is used to establish the angular momentum moment equation of the satellite relative to the satellite's center of mass, the momentum moment equation of the payload platform relative to the connection point, the satellite's center of mass translation equation, and the payload platform's center of mass translation equation based on the position vector, the angular velocity vector, the mass of the satellite platform, and the mass of the payload platform.

[0012] 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 methods for complex connected multi-body dynamics modeling of large inertia rotating loads.

[0013] In a fourth aspect, the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed in a computer, enables the computer to execute any of the above-mentioned methods for complex connected multi-body dynamics modeling of large inertia rotating loads.

[0014] 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.

[0015] The present invention provides a complex connection multi-body dynamics modeling method for a large inertia rotating load, which is applied to a satellite in which both a satellite platform and a payload platform are large inertia rigid bodies. By acquiring the mass, position vector and angular velocity vector of the satellite platform and the payload platform, and establishing the whole satellite angular momentum moment equation and center of mass translation equation of different degrees of freedom rotation joint characteristics and the momentum moment equation and center of mass translation equation of the load platform based on the law of conservation of momentum, the establishment of a complex connection multi-body dynamics model is completed, the problem of composite torque transfer characteristics between the satellite body and the large inertia rotating load is solved, and a theoretical basis is provided for the motion characteristics and index analysis of a satellite with large attachments and high rotation characteristics components and the controller design of a complex satellite. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] 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.

[0017] Figure 1 It is a flow chart of a complex connection multi-body dynamics modeling method for a large inertia rotating load provided by one embodiment of the present invention;

[0018] Figure 2is a schematic diagram of a reference coordinate system applied to a satellite system provided by an embodiment of the present invention;

[0019] Figure 3 is a hardware architecture diagram of a computing device provided by an embodiment of the present invention;

[0020] Figure 4 It is a structural diagram of a complex connection multi-body dynamics modeling device for a large inertia rotating load provided by one embodiment of the present invention. DETAILED DESCRIPTION

[0021] 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.

[0022] Since the space gyroscopic torque introduced during the high-speed rotation of the load platform of a large inertia rigid body is very obvious, constraints are imposed on the capacity of the bearing joints. During the movement, the main axis inertia difference of the load platform's moment of inertia introduces attitude interference of angular velocity frequency doubling characteristics into the attitude movement of the entire satellite, and the center of mass installation position offset and inertia distribution uneven characteristics of the load platform will also cause interference of different characteristics to the load platform and the entire satellite platform. The control stability fluctuation effect of the load platform introduces the motion characteristics of the entire satellite platform, which brings difficulty to the controller design of the entire satellite platform. Therefore, the present invention proposes to complete the establishment of a complex connection multi-body dynamic model of a large inertia rotating load based on momentum conservation.

[0023] Please refer to Figure 1 The embodiment of the present invention provides a complex connection multi-body dynamics modeling method for a large inertia rotating load, which is applied to a satellite in which both the satellite platform and the load platform are large inertia rigid bodies, including:

[0024] Step 100, establishing a reference coordinate system of the satellite;

[0025] Step 102, obtaining the position vector and angular velocity vector of the satellite platform and the payload platform according to the reference coordinate system;

[0026] Step 104, based on the position vector, angular velocity vector, mass of the satellite platform and mass of the payload platform, establish the angular momentum equation of the satellite relative to the satellite center of mass, the momentum equation of the payload platform relative to the connection point, the satellite center of mass translation equation and the payload platform center of mass translation equation.

[0027] In the present invention, in a satellite system in which both the satellite platform and the payload platform are large inertia rigid bodies, by acquiring the mass, position vector and angular velocity vector of the satellite platform and the payload platform, and based on the law of conservation of momentum, the angular momentum moment equation and center of mass translation equation of the whole satellite with different degrees of freedom rotation joint characteristics and the momentum moment equation and center of mass translation equation of the load platform are established, the establishment of a complex connected multi-body dynamics model is completed, the problem of composite torque transfer characteristics between the satellite body and the large inertia rotation payload is solved, and a theoretical basis is provided for the motion characteristics and index analysis of satellites with large attachments and high rotation characteristics components and the controller design of complex satellites.

[0028] It should be noted that the payload platform and the satellite platform are connected via a connection point (eg, a hinge connection point), and the satellite includes the payload platform and the satellite platform. The large inertia payload is preferably such that the mass of the payload platform itself is equivalent to the mass of the satellite platform.

[0029] Described below Figure 1 How the various steps are performed.

[0030] First, for step 100, the reference coordinate system includes the geocentric inertial coordinate system, the satellite platform coordinate system, the whole satellite platform coordinate system and the payload platform coordinate system.

[0031] Specifically, Figure 2 As shown, for the geocentric inertial coordinate system, with the origin O E is the center of mass of the Earth, O E X E The axis points to the 2000.0 mean vernal equinox, O E Z E The axis is perpendicular to the 2000.0 flat equatorial plane and is consistent with the direction of the Earth's rotation angular velocity. E Y E Axis and O E X E , O E Z E The axes form a right-hand system;

[0032] For the satellite platform coordinate system, the origin O is the center of the connection surface between the satellite and the carrier, O x The 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-hand system;

[0033] For the whole satellite platform coordinate system, the origin Oc is the mass center of the whole satellite, and the XcYcZc axis is parallel to the satellite platform coordinate system;

[0034] For the payload platform coordinate system, the origin Oi is the connection point between the payload platform and the satellite platform, and the XiYiZi axis is parallel to the satellite platform coordinate system.

[0035] In step 102, combining Figure 2 As shown, the position vector and angular velocity vector of the satellite platform and the payload platform are obtained according to the reference coordinate system, including:

[0036] Get the first angular velocity vector of the satellite platform relative to the inertial system in the satellite platform coordinate system oh bs , the second angular velocity vector of the payload platform relative to the satellite platform in the payload platform coordinate system oh i ;

[0037] For the first angular velocity vector oh bs and the second angular velocity vector oh i Sum the load platform to get the third velocity vector in the inertial space oh is ; oh is =ω bs +oh i ;

[0038] In the satellite platform coordinate system, obtain the first position vector from the origin of the satellite platform coordinate system to the center of mass of the satellite platform r co , the second position vector to the satellite's centroid r c , the third position vector to the connection point r oi ;

[0039] In the load platform coordinate system, obtain the fourth position vector from the connection point to the center of mass of the load platform r ci ;

[0040] In the geocentric inertial coordinate system, obtain the fifth position vector from the origin of the geocentric inertial coordinate system to the satellite's center of mass R 0.

[0041] Specifically, it also includes: a sixth position vector r n , ;

[0042] In the geocentric inertial coordinate system, the seventh position vector from the origin of the geocentric inertial coordinate system to the center of mass of the satellite platform is R c ; .

[0043] Specifically, the orientation of the rigid body in space is described by the orientation of the coordinate system fixed on the rigid body relative to the reference system, and the vector representation of each spatial orientation is given. Among them, the center of mass and mass relationship between the satellite platform and the payload platform is: , where the satellite platform mass is m 0 The mass of the load platform is m i , the total mass of the entire star system is: m = m 0 + m i , that is, the mass of the satellite including the satellite platform and the payload platform is m .

[0044] In the present invention, the first-order and second-order derivatives of the space pointing vector are given according to the relationship between the time derivative of any vector in the space rotating coordinate system relative to the inertial system and the time derivative relative to the rotating coordinate system. The time derivative of any vector in the rotating coordinate system is ,in u is an arbitrary vector; represents the first-order time derivative relative to the geocentric inertial coordinate system, Represents the first-order time derivative of the coordinate system rotating relative to the body; represents the second-order time derivative relative to the geocentric inertial coordinate system, It represents the second-order time derivative of the rotation coordinate system relative to the body. Among them, the first-order derivatives of the position vector and the angular velocity vector are calculated as follows:

[0045]

[0046]

[0047]

[0048]

[0049] The second derivative of the position vector is calculated as follows:

[0050]

[0051]

[0052]

[0053]

[0054]

[0055] Among them, the middle term .

[0056] For step 104, the angular momentum equation of the satellite relative to the satellite mass center is established by the following method:

[0057] Get the first moment of inertia of the load platform J ic and the second moment of inertia of the satellite platform J o ;

[0058] According to the mass of the load platform m i , the second position vector r c , the third position vector r oi , the fourth position vector r ci , the fifth position vector R 0. The third angular velocity vector oh is and the first moment of inertia J ic Based on the law of conservation of angular momentum, the first angular momentum equation of the payload platform relative to the satellite mass center is obtained; the first angular momentum equation is:

[0059]

[0060] According to the quality of the satellite platform m 0 , first position vector r co , the second position vector r c , the fifth position vector R 0. First angular velocity vector oh bs and the second moment of inertia J o Based on the law of conservation of angular momentum, the second angular momentum equation of the satellite platform relative to the satellite mass center is obtained; the second angular momentum equation is:

[0061]

[0062] The first angular momentum moment equation and the second angular momentum moment equation are summed to obtain the angular momentum moment equation of the satellite relative to the satellite mass center; the angular momentum moment equation is:

[0063] .

[0064] In step 104, the momentum equation of the load platform relative to the connection point is established by the following method:

[0065] Get the first moment of inertia of the load platform J ic ;

[0066] According to the mass of the load platform m i , the fourth position vector r ci , the fifth position vector R 0. Sixth position vector r n 、The third angular velocity vector oh is and the first moment of inertia J ic Based on the law of conservation of angular momentum, the momentum equation of the load platform relative to the connection point is obtained, which is:

[0067] .

[0068] In step 104, the satellite's center of mass translation equation is established by the following method:

[0069] According to the quality of the satellite platform m 0 , the mass of the load platform m i , seventh position vector R c , based on the center of mass motion theorem, the satellite's center of mass translation equation is obtained; F c is the external force received by the satellite’s center of mass, and the center of mass translation equation is:

[0070] .

[0071] In step 104, the center of mass translation equation of the load platform is established by the following method:

[0072] According to the mass of the load platform m i , the second position vector r c , the third position vector, the fourth position vector and the fifth position vector, and the center of mass translation equation of the load platform is obtained based on the center of mass motion theorem. F i is the external force received by the center of mass of the load platform, and the translation equation of the center of mass of the load platform is:

[0073] .

[0074] In a preferred embodiment, the center of mass translation equation of the satellite platform is:

[0075]

[0076] in, F b is the external force received by the center of mass of the satellite platform;

[0077] m 0 The quality of the satellite platform;

[0078] is the second-order time derivative of the fifth position vector relative to the geocentric inertial coordinate system;

[0079] is the second-order time derivative of the first position vector relative to the geocentric inertial coordinate system;

[0080] is the second-order time derivative of the second position vector relative to the geocentric inertial coordinate system.

[0081] In a preferred embodiment, after step 104, the method further includes:

[0082] Determine the introduced dynamic unbalance disturbance term, static disturbance term and main axis inertia disturbance term from the angular momentum moment equation of the satellite relative to the satellite mass center;

[0083] The satellite is feedforward controlled according to the dynamic imbalance disturbance, static disturbance and main axis inertia disturbance.

[0084] Specifically, taking the +X high-speed rotation of the payload platform as an example, the angular momentum interference characteristics of the payload platform under the high-speed motion characteristics of the payload platform and the angular momentum interference characteristics of the entire satellite are analyzed. Assuming that the angular velocity direction of the payload platform is a high-speed rotation in the +X direction, the angular velocity is expressed in the payload platform coordinate system as .

[0085] For the dynamic unbalance disturbance term, the angular momentum disturbance term of the load platform is introduced T i1 for:

[0086]

[0087] The angular momentum interference term of the entire satellite platform (i.e., satellite) is introduced T b1 for:

[0088]

[0089] in, A bi It is the transformation matrix from the payload platform to the whole satellite platform.

[0090] In the present invention, when the load platform moves at high speed, the attitude disturbance introduced by the inertia mass characteristics of the load platform can be considered as the dynamic unbalance disturbance introduced by the movement of two equal mass blocks with a phase angle difference of 180° on the rotor of the load platform, which is reflected in the whole satellite platform as oh i Interference items of the same frequency.

[0091] For the static disturbance term, the angular momentum disturbance term of the load platform is introduced T i2 for: , the angular momentum disturbance of the whole satellite platform introduced T b2 for .

[0092] In the present invention, considering the working condition of the load platform rotating at high speed, oh i Much higher than oh bs , N foi middle As the main interference item, considering that the magnitude of the mass center offset of the load platform is much smaller than the magnitude of the axial span, the position offset in the +Y direction will generate an interference torque in the -Z direction, and the magnitude of the interference torque is ; If there is a position offset in the +Z direction, an interference torque in the +Y direction will be generated, and the magnitude of the interference torque is , where the subscript x , y , z It represents the components of the vector in the three coordinate axes of the satellite platform coordinate system. This interference can be considered as the static interference term introduced by the mass center movement under the high-speed motion characteristics of the payload platform, which is reflected in the whole satellite platform as and oh i Interference items of the same frequency.

[0093] For the main axis inertia interference term, the main axis inertia, that is, the X-axis inertia of the rotating axis, is considered. The angular momentum interference term of the load platform introduced by the main interference torque is T i3 for:

[0094]

[0095] The angular momentum disturbance term of the whole satellite platform introduced T b3 for: .

[0096] In the present invention, the main axis inertia interference term of the whole satellite platform can be decomposed into a Z-axis constant term and a double frequency interference term of the load platform. The constant term can be considered as the gyroscopic torque generated during the rotation of the load platform.

[0097] In the present invention, by analyzing the transfer characteristics of the angular momentum moment equation of the satellite relative to the satellite's center of mass, the dynamic unbalance interference term, static interference term and main axis inertia interference term introduced during the movement of the large inertia rotating load are determined, so that the satellite system is further feedforward controlled and compensated based on these interference terms to improve the control accuracy of the entire satellite.

[0098] The present invention completes the modeling of the dynamic characteristics of the whole satellite and the dynamic characteristics of the load platform with large inertia rotating loads, and realizes the modeling of the attitude kinematic characteristics of the satellite platform and the load platform that adapt to large rotation angular velocity. At the same time, it also realizes the satellite transfer characteristic analysis and index decomposition, providing necessary guarantees for the feedforward design of the whole satellite platform controller and the feedforward design of the load platform controller. The method is simple and practical, and is suitable for engineering applications.

[0099] like Figure 3 , Figure 4 As shown, the embodiment of the present invention provides a complex connection multi-body dynamics modeling device for large inertia rotating loads. The device embodiment can be implemented by software, or by hardware or a combination of software and hardware. From the hardware level, Figure 3 As shown, a hardware architecture diagram of a computing device in which a complex connection multi-body dynamics modeling device for a large inertia rotating load provided by an embodiment of the present invention is located, except Figure 3 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 4 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 complex connection multi-body dynamics modeling device for a large inertia rotating load, which is applied to a satellite in which both the satellite platform and the load platform are large inertia rigid bodies, and includes:

[0100] A coordinate establishment module 400, used to establish a reference coordinate system of the satellite;

[0101] A space pointing module 402, configured to obtain the position vector and angular velocity vector of the satellite platform and the payload platform according to the reference coordinate system;

[0102] The model building module 404 is used to establish the angular momentum moment equation of the satellite relative to the satellite's center of mass, the momentum moment equation of the payload platform relative to the connection point, the satellite's center of mass translation equation, and the payload platform's center of mass translation equation based on the position vector, the angular velocity vector, the mass of the satellite platform, and the mass of the payload platform.

[0103] In some specific implementations, the coordinate establishment module 400 may be used to execute the above step 100 , the spatial pointing module 402 may be used to execute the above step 102 , and the model construction module 404 may be used to execute the above step 104 .

[0104] In some specific implementations, the reference coordinate system includes a geocentric inertial coordinate system, a satellite platform coordinate system, a whole-satellite platform coordinate system, and a payload platform coordinate system.

[0105] In some specific implementations, the space pointing module 402 is further configured to perform the following operations:

[0106] The position vector and angular velocity vector of the satellite platform and the payload platform are obtained according to the reference coordinate system, including:

[0107] Get the first angular velocity vector of the satellite platform relative to the inertial system in the satellite platform coordinate system oh bs , the second angular velocity vector of the payload platform relative to the satellite platform in the payload platform coordinate system oh i ;

[0108] For the first angular velocity vector oh bs and the second angular velocity vector oh i Sum the load platform to get the third velocity vector in the inertial space oh is ; oh is =ω bs +oh i ;

[0109] In the satellite platform coordinate system, obtain the first position vector from the origin of the satellite platform coordinate system to the center of mass of the satellite platform r co , the second position vector to the satellite's centroid r c , the third position vector to the connection point r oi ;

[0110] In the load platform coordinate system, obtain the fourth position vector from the connection point to the center of mass of the load platform r ci ;

[0111] In the geocentric inertial coordinate system, obtain the fifth position vector from the origin of the geocentric inertial coordinate system to the satellite's center of mass R 0.

[0112] In some specific implementations, the model building module 404 is further configured to perform the following operations:

[0113] Get the first moment of inertia of the load platform J ic and the second moment of inertia of the satellite platform J o ;

[0114] According to the mass of the load platform m i , the second position vector r c , the third position vector r oi , the fourth position vector r ci , the fifth position vector R 0. The third angular velocity vector oh is and the first moment of inertia J ic , based on the law of conservation of angular momentum, the first angular momentum equation of the payload platform relative to the satellite mass center is obtained;

[0115] According to the quality of the satellite platform m 0 , first position vector r co , the second position vector r c , the fifth position vector R 0. First angular velocity vector oh bs and the second moment of inertia J o , based on the law of conservation of angular momentum, the second angular momentum equation of the satellite platform relative to the satellite's center of mass is obtained;

[0116] The first angular momentum moment equation and the second angular momentum moment equation are summed to obtain the angular momentum moment equation of the satellite relative to the satellite mass center; the angular momentum moment equation is:

[0117] .

[0118] In some specific implementations, the model building module 404 is further configured to perform the following operations:

[0119] Get the first moment of inertia of the load platform J ic ;

[0120] According to the mass of the load platform m i , the fourth position vector r ci, the fifth position vector R 0. Sixth position vector r n 、The third angular velocity vector oh is and the first moment of inertia J ic Based on the law of conservation of angular momentum, the momentum equation of the load platform relative to the connection point is obtained, which is:

[0121] .

[0122] In some specific implementations, the model building module 404 is further configured to perform the following operations:

[0123] According to the quality of the satellite platform m 0 , the mass of the load platform m i , seventh position vector R c , based on the center of mass motion theorem, the center of mass translation equation of the satellite is obtained; the center of mass translation equation is:

[0124] .

[0125] In some specific implementations, the model building module 404 is further configured to perform the following operations:

[0126] The center of mass translation equation of the load platform is established by the following method:

[0127] According to the mass of the load platform m i , the second position vector r c , the third position vector, the fourth position vector and the fifth position vector, the center of mass translation equation of the load platform is obtained based on the center of mass motion theorem. The center of mass translation equation of the load platform is:

[0128] .

[0129] In some more specific embodiments, the device further includes: an analysis module, which is further configured to perform the following operations:

[0130] In a preferred embodiment, after step 104, the method further includes:

[0131] Determine the introduced dynamic unbalance disturbance term, static disturbance term and main axis inertia disturbance term from the angular momentum moment equation of the satellite relative to the satellite mass center;

[0132] The satellite is feedforward controlled according to the dynamic imbalance disturbance, static disturbance and main axis inertia disturbance.

[0133] It is to be understood that the structure illustrated in the embodiment of the present invention does not constitute a specific limitation on a complex connection multi-body dynamic modeling device for a large inertia rotating load. In other embodiments of the present invention, a complex connection multi-body dynamic modeling device for a large inertia rotating load 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.

[0134] 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.

[0135] 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, a complex connection multi-body dynamics modeling method for a large inertia rotating load in any embodiment of the present invention is implemented.

[0136] An embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the processor executes a complex connection multi-body dynamics modeling method for a large inertia rotating load in any embodiment of the present invention.

[0137] 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 a complex connection multi-body dynamics modeling method for a large inertia rotating load as described in any of the above embodiments.

[0138] 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.

[0139] 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.

[0140] 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 via a communication network.

[0141] 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.

[0142] 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.

[0143] 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.

[0144] 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.

[0145] 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 complex connection multi-body dynamics modeling method for large inertia rotating loads, characterized in that: Applied to satellites where both the satellite platform and the payload platform are large inertia rigid bodies, including: Establishing a reference coordinate system for the satellite; Acquire the position vector and angular velocity vector of the satellite platform and the payload platform according to the reference coordinate system; According to the position vector, the angular velocity vector, the mass of the satellite platform and the mass of the payload platform, establish an angular momentum moment equation of the satellite relative to the satellite mass center, an momentum moment equation of the payload platform relative to the connection point, a mass center translation equation of the satellite and a mass center translation equation of the payload platform; The reference coordinate system includes a geocentric inertial coordinate system, a satellite platform coordinate system, a whole-satellite platform coordinate system and a payload platform coordinate system; The step of acquiring the position vector and the angular velocity vector of the satellite platform and the payload platform according to the reference coordinate system comprises: Acquire a first angular velocity vector of the satellite platform relative to an inertial system in the satellite platform coordinate system and a second angular velocity vector of the payload platform relative to the satellite platform in the payload platform coordinate system; Summing the first angular velocity vector and the second angular velocity vector to obtain a third angular velocity vector of the load platform in the inertial space; In the satellite platform coordinate system, obtain a first position vector from the origin of the satellite platform coordinate system to the center of mass of the satellite platform, a second position vector to the center of mass of the satellite, and a third position vector to the connection point; In the load platform coordinate system, obtaining a fourth position vector from the connection point to the center of mass of the load platform; In the geocentric inertial coordinate system, obtaining a fifth position vector from the origin of the geocentric inertial coordinate system to the center of mass of the satellite; The angular momentum equation of the satellite relative to the satellite mass center is established by the following method: Acquire a first moment of inertia of the payload platform and a second moment of inertia of the satellite platform; According to the mass of the payload platform, the second position vector, the third position vector, the fourth position vector, the fifth position vector, the third angular velocity vector and the first moment of inertia, a first angular momentum moment equation of the payload platform relative to the satellite mass center is obtained based on the law of conservation of angular momentum; Obtaining a second angular momentum moment equation of the satellite platform relative to the satellite mass center based on the law of conservation of angular momentum according to the mass of the satellite platform, the first position vector, the second position vector, the fifth position vector, the first angular velocity vector, and the second moment of inertia; Summing the first angular momentum moment equation and the second angular momentum moment equation to obtain an angular momentum moment equation of the satellite relative to the satellite mass center; and, The momentum equation of the load platform relative to the connection point is established by the following method: Obtaining a first moment of inertia of the load platform; According to the mass of the load platform, the second position vector, the third position vector, the fourth position vector, the fifth position vector, the third angular velocity vector and the first moment of inertia, a momentum moment equation of the load platform relative to the connection point is obtained based on the law of conservation of angular momentum; The center-of-mass translation equation of the satellite is established by the following method: Obtaining a center of mass translation equation of the satellite based on the center of mass motion theorem according to the mass of the satellite platform, the mass of the payload platform, the first position vector, the second position vector, and the fifth position vector; and, The center of mass translation equation of the load platform is established by the following method: According to the mass of the load platform, the second position vector, the third position vector, the fourth position vector and the fifth position vector, a center of mass translation equation of the load platform is obtained based on the center of mass motion theorem.

2. The method according to claim 1, characterized in that The angular momentum equation of the satellite relative to the satellite mass center is: in, M is the angular momentum of the satellite relative to the satellite's center of mass; ω is is the third velocity vector of the load platform in the inertial space; is the first-order time derivative of the third angular velocity vector relative to the geocentric inertial coordinate system; ω bs is the first angular velocity vector of the satellite platform relative to the inertial system in the satellite platform coordinate system; is the first-order time derivative of the first angular velocity vector relative to the geocentric inertial coordinate system; m i is the mass of the load platform; m 0 is the mass of the satellite platform; J ic is the first moment of inertia of the load platform; J o is the second moment of inertia of the satellite platform; In the satellite platform coordinate system, r co , r c , r oi are respectively a first position vector from the origin of the satellite platform coordinate system to the mass center of the satellite platform, a second position vector to the mass center of the satellite, and a third position vector to the connection point; , are respectively the second-order time derivatives of the first position vector and the second position vector relative to the geocentric inertial coordinate system; In the load platform coordinate system, r ci A fourth position vector from the connection point to the center of mass of the load platform; is the second-order time derivative of the fourth position vector relative to the load platform coordinate system; In the geocentric inertial coordinate system, R 0 is the fifth position vector from the origin of the geocentric inertial coordinate system to the satellite's center of mass; is the second-order time derivative of the fifth position vector relative to the geocentric inertial coordinate system; r n is the sixth position vector; is the second-order time derivative of the sixth position vector relative to the geocentric inertial coordinate system; and / or, The momentum equation of the load platform relative to the connection point is: in, M ic is the angular momentum of the load platform relative to the connection point; m i is the mass of the load platform; J ic is the first moment of inertia of the load platform; ω is is the third velocity vector of the load platform in the inertial space; is the first-order time derivative of the third angular velocity vector relative to the geocentric inertial coordinate system; In the geocentric inertial coordinate system, R 0 is a fifth position vector from the origin of the geocentric inertial coordinate system to the center of mass of the satellite; is the second-order time derivative of the fifth position vector relative to the geocentric inertial coordinate system; In the satellite platform coordinate system, r c , r oi are respectively a second position vector from the origin of the satellite platform coordinate system to the satellite mass center and a third position vector to the connection point; In the load platform coordinate system, r ci A fourth position vector from the connection point to the center of mass of the load platform; r n is the sixth position vector; is the second-order time derivative of the sixth position vector relative to the geocentric inertial coordinate system.

3. The method according to claim 1, characterized in that The satellite's center of mass translation equation is: in, F c is the external force received by the center of mass of the satellite; m 0 is the mass of the satellite platform; m i is the mass of the load platform; In the geocentric inertial coordinate system, R c A seventh vector from the origin of the geocentric inertial coordinate system to the center of mass of the satellite platform; is the second-order time derivative of the seventh vector relative to the geocentric inertial coordinate system; and / or, The center of mass translation equation of the load platform is: in, F i is the external force received by the center of mass of the load platform; m i is the mass of the load platform; is the second-order time derivative of the fifth position vector relative to the geocentric inertial coordinate system; In the satellite platform coordinate system, r c , r oi are respectively a second position vector from the origin of the satellite platform coordinate system to the satellite mass center and a third position vector to the connection point; In the load platform coordinate system, r ci A fourth position vector from the connection point to the center of mass of the load platform; r n is the sixth position vector; is the second-order time derivative of the sixth position vector relative to the geocentric inertial coordinate system.

4. The method according to any one of claims 1 to 3, characterized in that: After establishing the angular momentum moment equation of the satellite relative to the satellite mass center, the momentum moment equation of the payload platform relative to the connection point, the mass center translation equation of the satellite, and the mass center translation equation of the payload platform, the method further includes: Determining the introduced dynamic unbalance interference term, static interference term and main axis inertia interference term from the angular momentum moment equation of the satellite relative to the satellite mass center; The satellite is feedforward controlled according to the dynamic unbalance disturbance term, the static disturbance term and the main axis inertia disturbance term.

5. A complex connection multi-body dynamics modeling device for large inertia rotating loads for implementing the complex connection multi-body dynamics modeling method for large inertia rotating loads as claimed in any one of claims 1 to 4, characterized in that: Applied to satellites where both the satellite platform and the payload platform are large inertia rigid bodies, including: A coordinate establishment module, used to establish a reference coordinate system of the satellite; A space pointing module, used for acquiring the position vector and angular velocity vector of the satellite platform and the payload platform according to the reference coordinate system; The model building module is used to establish the angular momentum moment equation of the satellite relative to the satellite's center of mass, the momentum moment equation of the payload platform relative to the connection point, the satellite's center of mass translation equation, and the payload platform's center of mass translation equation based on the position vector, the angular velocity vector, the mass of the satellite platform, and the mass of the payload platform.

6. 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 4 is implemented.

7. 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 4.

Images