Euler angle calculation method, device, equipment and medium

Abstract

The present disclosure provides a method, device, equipment and medium for calculating Euler angles, which relate to the field of aerospace technology. The method includes: obtaining the right ascension, declination and first direction vector corresponding to the observation direction of the satellite platform corresponding to the designated observation direction of the satellite camera; calculating the second direction vector corresponding to the right ascension and the declination; calculating the rotation matrix from the designated observation direction to the observation direction of the satellite platform according to the first direction vector and the second direction vector; calculating the Euler angle of the designated observation direction of the satellite camera according to the rotation matrix. The calculation method can quickly and accurately solve the Euler angle of the designated observation direction of the satellite camera from the celestial right ascension and declination. Moreover, the calculation method can fully consider various rotation sequences of aerospace engineering, has a wide range of uses and strong applicability. In addition, the calculation method has good compatibility, low calculation complexity, fast running speed, simple algorithm, and easy engineering implementation.

Description

Technical Field

[0001] The present disclosure relates to the field of aerospace technology, and in particular to a method, device, equipment and medium for calculating Euler angles. Background Art

[0002] A space-based telescope refers to a telescope device installed on a space-based platform to observe the space. Compared with ground-based telescopes, space-based telescopes have the following main advantages: space-based observations are not affected by sunlight and can be observed all day long; space-based observations are not affected by clouds or weather and can be observed all day long; the sky background of space-based observations is very dark and is not affected by atmospheric extinction. However, when conducting demonstrations, simulations, mission planning, etc. of space-based telescopes, it is often necessary to solve the initial pointing of the camera from the right ascension and declination of the observation direction for satellites running in inertial orientation mode. However, the results are completely different due to different observation directions and the installation relationship between the camera and the satellite platform. Therefore, how to quickly and accurately solve the initial pointing of the camera from the right ascension and declination of the observation direction for satellites running in inertial orientation mode is a problem that technicians in this field urgently need to solve. Summary of the invention

[0003] In view of the above technical problems, the first aspect of the present disclosure provides a method for calculating Euler angles, including: obtaining the right ascension and declination corresponding to the specified observation direction of the satellite camera and the first direction vector corresponding to the observation direction of the satellite platform; calculating the second direction vector corresponding to the right ascension and declination; calculating the rotation matrix from the specified observation direction to the observation direction of the satellite platform according to the first direction vector and the second direction vector; and calculating the Euler angle of the specified observation direction of the satellite camera according to the rotation matrix.

[0004] According to an embodiment of the present disclosure, a first direction vector of a satellite platform in an inertial orientation mode is acquired.

[0005] According to an embodiment of the present disclosure, calculating the second direction vector corresponding to the right ascension and the declination specifically includes:

[0006]

[0007] Calculate the second direction vector A = [a x , a y , a z ] T , where Dec represents the right ascension of the specified observation direction, RA represents the declination of the specified observation direction, and a x , a y , a z The unit basis vectors representing the specified observation direction of the satellite camera in the inertial coordinate system or the J2000 coordinate system.

[0008] According to an embodiment of the present disclosure, the calculation of the rotation matrix of the specified observation direction to the observation direction of the satellite platform according to the first direction vector and the second direction vector specifically includes:

[0009] A=R A / B B,

[0010] Calculate the rotation matrix R A / B , where A is the second direction vector and B is the first direction vector.

[0011] According to an embodiment of the present disclosure, calculating the Euler angle of a specified observation direction of a satellite camera according to a rotation matrix specifically includes: determining a rotation order from the specified observation direction to the observation direction of a satellite platform; based on the rotation order, calculating the Euler angle of the specified observation direction of the satellite platform according to the rotation matrix, wherein the Euler angle includes a pitch angle, a yaw angle, and a roll angle.

[0012] According to an embodiment of the present disclosure, the rotation sequence includes 12 rotation sequences suitable for aerospace engineering.

[0013] A second aspect of the present disclosure provides a device for calculating Euler angles, including: an acquisition module, used to acquire the right ascension and declination corresponding to the specified observation direction of the satellite camera and a first direction vector corresponding to the observation direction of the satellite platform; a first calculation module, used to calculate the second direction vector corresponding to the right ascension and the declination; a second calculation module, used to calculate the rotation matrix from the specified observation direction to the observation direction of the satellite platform according to the first direction vector and the second direction vector; a third calculation module, used to calculate the Euler angle of the specified observation direction of the satellite camera according to the rotation matrix.

[0014] A third aspect of the present disclosure provides an electronic device, comprising: one or more processors; and a memory for storing one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the above method.

[0015] A fourth aspect of the present disclosure provides a computer-readable storage medium having executable instructions stored thereon, which, when executed by a processor, enables the processor to implement the above method.

[0016] The Euler angle calculation method, device, and medium provided by the embodiments of the present disclosure can at least achieve the following technical effects:

[0017] Based on the direction vectors corresponding to the right ascension and declination of the satellite camera observation direction and the direction vector corresponding to the satellite observation platform, the Euler angle of the specified observation direction of the star camera can be quickly and accurately solved from the celestial right ascension and declination. In addition, the calculation method can calculate the observation direction Euler angle by determining different elements of the rotation matrix by rotating the Euler angle in different rotation orders, which can fully consider the various rotation orders of aerospace engineering, has a wide range of uses, and is highly applicable. In addition, the calculation method has good compatibility, low computational complexity, fast running speed, simple algorithm, and is easy to implement in engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and other objects, features and advantages of the present disclosure will become more apparent through the following description of the embodiments of the present disclosure with reference to the accompanying drawings, in which:

[0019] Figure 1 The flowchart of the method for calculating Euler angles according to an embodiment of the present disclosure is schematically shown.

[0020] Figure 2 A block diagram of a calculation device based on Euler angles according to an embodiment of the present disclosure is schematically shown.

[0021] Figure 3 A block diagram of an electronic device suitable for implementing the method described above according to an embodiment of the present invention is schematically shown. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solutions and advantages of the present disclosure more clearly understood, the present disclosure is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present disclosure, rather than all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present disclosure.

[0023] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The terms "comprise", "include", etc. used herein indicate the existence of the features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0024] In the present disclosure, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or can communicate with each other; it can be a direct connection, or it can be indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present disclosure can be understood according to specific circumstances.

[0025] In the description of the present disclosure, it is necessary to understand that the terms "longitudinal", "length", "circumferential", "front", "rear", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present disclosure and simplifying the description, and do not indicate or imply that the subsystem or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present disclosure.

[0026] Throughout the drawings, the same elements are represented by the same or similar reference numerals. Conventional structures or configurations will be omitted when they may cause confusion in the understanding of the present disclosure. The shapes, sizes, and positional relationships of the components in the drawings do not reflect the actual size, proportion, and actual positional relationship. In addition, in the present disclosure, any reference symbol between brackets should not be constructed as a limitation to the present disclosure.

[0027] Similarly, in order to simplify the present disclosure and help understand one or more of the various disclosed aspects, in the above description of the exemplary embodiments of the present disclosure, the various features of the present disclosure are sometimes grouped together into a single embodiment, figure, or description thereof. The description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" and the like means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0028] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the feature. In the description of the present disclosure, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0029] In order to solve the technical problem in the prior art of how to calculate the observation pointing parameters of the camera from the right ascension and declination in the inertial orientation state of the satellite, the disclosed embodiment provides a method for calculating the Euler angle, including: obtaining the right ascension and declination corresponding to the specified observation pointing of the satellite camera and the first direction vector corresponding to the observation direction of the satellite platform. Calculate the second direction vector corresponding to the right ascension and declination. Calculate the rotation matrix from the specified observation pointing to the observation direction of the satellite platform based on the first direction vector and the second direction vector. Calculate the Euler angle of the specified observation pointing of the satellite camera based on the rotation matrix. A similar introduction is given below in conjunction with specific embodiments.

[0030] Figure 1 The flowchart of the method for calculating Euler angles according to an embodiment of the present disclosure is schematically shown.

[0031] like Figure 1 As shown, the method for calculating the Euler angle may include, for example, operations S101 to S104.

[0032] In operation S101, the right ascension and declination corresponding to the designated observation direction of the satellite camera and the first direction vector corresponding to the observation direction of the satellite platform are obtained, and the second direction vector corresponding to the right ascension and declination is calculated.

[0033] In one embodiment of the present disclosure, a first direction vector of the satellite platform observation direction in the inertial orientation mode can be obtained. The direction vector can be represented based on the coordinate system unit basis vector of the satellite platform body. For example, the coordinate system unit basis vector of the satellite platform body is recorded as B=[b x , b y , b z ] T .

[0034] In operation S102, a second direction vector corresponding to the right ascension and the declination is calculated.

[0035] In one embodiment of the present disclosure, according to

[0036]

[0037] Calculate the second direction vector A = [a x , a y , a z ] T , where Dec represents the right ascension of the specified observation direction, RA represents the declination of the specified observation direction, and a x , a y , a z The unit basis vectors representing the specified observation direction of the satellite camera in the inertial coordinate system or the J2000 coordinate system.

[0038] In operation S103, a rotation matrix from the designated observation direction to the observation direction of the satellite platform is calculated according to the first direction vector and the second direction vector.

[0039] In one embodiment of the present disclosure, according to

[0040] A=R A / B B,

[0041] Calculate the rotation matrix R from the specified observation direction to the satellite platform observation direction A / B , where A is the second direction vector and B is the first direction vector.

[0042] Since the first direction vector and the second direction vector are both three-dimensional vectors, the rotation matrix R A / B For example, it can be expressed as:

[0043]

[0044] In operation S104 , the Euler angle of the specified observation direction of the satellite camera is calculated according to the rotation matrix.

[0045] In one embodiment of the present disclosure, calculating the Euler angle of the specified observation direction of the satellite camera according to the rotation matrix may specifically include: determining the rotation order of the specified observation direction to the observation direction of the satellite platform. Based on the rotation order, calculating the Euler angle of the specified observation direction of the satellite camera according to the rotation matrix. The Euler angle includes a pitch angle, a yaw angle, and a roll angle.

[0046] For example, let the pitch angle be The yaw angle is θ, the roll angle is φ, The angle of rotation around the x-axis, θ is the angle of rotation around the y-axis, and φ is the angle of rotation around the z-axis. Based on this, there are three cases of primitive rotation, rotation around the x-axis:

[0047]

[0048] Rotation around the y-axis:

[0049]

[0050] Rotation around the z-axis:

[0051]

[0052] Since there may be multiple rotation orders of Euler angles, such as x->y->z, x->z->y, y->x->z, y->z->x, z->x->y, z->y->x, z->x->y, z->y->x, their corresponding rotation matrices are: Therefore, the rotation order needs to be determined before solving the rotation matrix.

[0053] In the embodiment of the present disclosure, there are 12 rotation sequences commonly used in aerospace engineering, for example, may include: x->y->z, x->z->y, y->x->z, y->z->x, z->x->y, z->y->x, x->y->x, x->y->x, x->z->x, x->z->x, y->x->x, y->x->y, y->z->y, z->x->x, z->x->y, z->x->y, z->x->z, z->x->y, z->x->z, z->y->z.

[0054] When the rotation order is x->y->z, the Euler angle of the satellite camera's specified observation direction can be:

[0055]

[0056] When the rotation order is x->z->y, the Euler angle of the satellite camera's specified observation direction can be:

[0057]

[0058] When the rotation order is y->x->z, the Euler angle of the satellite camera's specified observation direction can be:

[0059]

[0060] When the rotation order is y->z->x, the Euler angle of the satellite camera's specified observation direction can be:

[0061]

[0062] When the rotation order is z->x->y, the Euler angle of the satellite camera's specified observation direction can be:

[0063]

[0064] When the rotation order is z->y->x, the Euler angle of the satellite camera's specified observation direction can be:

[0065]

[0066] When the rotation order is x->y->x, the Euler angle of the satellite camera's specified observation direction can be:

[0067]

[0068] When the rotation order is x->z->x, the Euler angle of the satellite camera's specified observation direction can be:

[0069]

[0070] When the rotation order is y->x->y, the Euler angle of the satellite camera's specified observation direction can be:

[0071]

[0072] When the rotation order is y->z->y, the Euler angle of the satellite camera's specified observation direction can be:

[0073]

[0074] When the rotation order is z->x->z, the Euler angle of the satellite camera's specified observation direction can be:

[0075]

[0076] When the rotation order is z->y->z, the Euler angle of the satellite camera's specified observation direction can be:

[0077]

[0078] At this point, based on the above operations, the process of calculating the camera's observation pointing parameters from right ascension and declination can be completed.

[0079] Figure 2 A block diagram of a Euler angle calculation device according to an embodiment of the present disclosure is schematically shown.

[0080] like Figure 2 As shown, the Euler angle calculation device 200 may include an acquisition module 210 , a first calculation module 220 , a second calculation module 230 and a third calculation module 240 .

[0081] The acquisition module 210 is used to acquire the right ascension and declination corresponding to the designated observation direction of the satellite camera and the first direction vector corresponding to the observation direction of the satellite platform.

[0082] The first calculation module 220 is used to calculate the second direction vector corresponding to the right ascension and the declination.

[0083] The second calculation module 230 is used to calculate the rotation matrix from the specified observation direction to the observation direction of the satellite platform according to the first direction vector and the second direction vector.

[0084] The fourth calculation module 240 is used to calculate the Euler angle of the specified observation direction of the satellite camera according to the rotation matrix.

[0085] According to the embodiments of the present invention, any one or more of the modules, submodules, units, and subunits, or at least part of the functions of any one of them can be implemented in one module. According to the embodiments of the present invention, any one or more of the modules, submodules, units, and subunits can be split into multiple modules for implementation. According to the embodiments of the present invention, any one or more of the modules, submodules, units, and subunits can be at least partially implemented as hardware circuits, such as field programmable gate arrays (FPGAs), programmable logic arrays (PLAs), systems on chips, systems on substrates, systems on packages, application specific integrated circuits (ASICs), or can be implemented by hardware or firmware in any other reasonable way of integrating or packaging the circuit, or implemented in any one of the three implementation methods of software, hardware, and firmware, or in any appropriate combination of any of them. Alternatively, according to the embodiments of the present invention, one or more of the modules, submodules, units, and subunits can be at least partially implemented as computer program modules, and when the computer program modules are run, the corresponding functions can be performed.

[0086] For example, any multiple of the acquisition module 210, the first calculation module 220, the second calculation module 230, and the third calculation module 240 can be combined in one module / unit / sub-unit for implementation, or any one of the modules / units / sub-units can be split into multiple modules / units / sub-units. Alternatively, at least part of the functions of one or more of these modules / units / sub-units can be combined with at least part of the functions of other modules / units / sub-units and implemented in one module / unit / sub-unit. According to an embodiment of the present disclosure, at least one of the acquisition module 210, the first calculation module 220, the second calculation module 230, and the third calculation module 240 can be at least partially implemented as a hardware circuit, such as a field programmable gate array (FPGA), a programmable logic array (PLA), a system on a chip, a system on a substrate, a system on a package, an application specific integrated circuit (ASIC), or can be implemented by hardware or firmware such as any other reasonable way of integrating or packaging the circuit, or by any one of the three implementation methods of software, hardware, and firmware, or by a suitable combination of any of them. Alternatively, at least one of the acquisition module 210 , the first calculation module 220 , the second calculation module 230 , and the third calculation module 240 may be at least partially implemented as a computer program module, and when the computer program module is executed, a corresponding function may be executed.

[0087] It should be noted that the Euler angle calculation device part in the embodiment of the present disclosure corresponds to the Euler angle calculation method part in the embodiment of the present disclosure, and their specific implementation details and the technical effects brought about are also the same, which will not be repeated here.

[0088] Figure 3A block diagram of an electronic device suitable for implementing the method described above according to an embodiment of the present invention is schematically shown. Figure 3 The electronic device shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0089] like Figure 3 As shown, the electronic device 300 according to an embodiment of the present invention includes a processor 301, which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM) 302 or a program loaded from a storage part 308 into a random access memory (RAM) 303. The processor 301 may, for example, include a general-purpose microprocessor (e.g., a CPU), an instruction set processor and / or a related chipset and / or a special-purpose microprocessor (e.g., an application-specific integrated circuit (ASIC)), etc. The processor 301 may also include an onboard memory for caching purposes. The processor 301 may include a single processing unit or multiple processing units for performing different actions of the method flow according to an embodiment of the present invention.

[0090] In RAM 303, various programs and data required for the operation of electronic device 300 are stored. Processor 301, ROM 302 and RAM 303 are connected to each other via bus 304. Processor 301 performs various operations of the method flow according to an embodiment of the present invention by executing the programs in ROM 302 and / or RAM 303. It should be noted that the program can also be stored in one or more memories other than ROM 302 and RAM 303. Processor 301 can also perform various operations of the method flow according to an embodiment of the present invention by executing the programs stored in the one or more memories.

[0091] According to an embodiment of the present invention, the electronic device 300 may further include an input / output (I / O) interface 305, which is also connected to the bus 304. The electronic device 300 may further include one or more of the following components connected to the I / O interface 305: an input portion 306 including a keyboard, a mouse, etc.; an output portion 307 including a cathode ray tube (CRT), a liquid crystal display (LCD), etc., and a speaker, etc.; a storage portion 308 including a hard disk, etc.; and a communication portion 309 including a network interface card such as a LAN card, a modem, etc. The communication portion 309 performs communication processing via a network such as the Internet. A drive 310 is also connected to the I / O interface 305 as needed. A removable medium 311, such as a magnetic disk, an optical disk, a magneto-optical disk, a semiconductor memory, etc., is installed on the drive 310 as needed, so that a computer program read therefrom is installed into the storage portion 308 as needed.

[0092] According to an embodiment of the present invention, the method flow according to an embodiment of the present invention can be implemented as a computer software program. For example, an embodiment of the present invention includes a computer program product, which includes a computer program carried on a computer-readable storage medium, and the computer program contains a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from the network through the communication part 309, and / or installed from the removable medium 311. When the computer program is executed by the processor 301, the above-mentioned functions defined in the system of the embodiment of the present invention are executed. According to an embodiment of the present invention, the system, equipment, device, module, unit, etc. described above can be implemented by a computer program module.

[0093] The present invention also provides a computer-readable storage medium, which may be included in the device / apparatus / system described in the above embodiment; or may exist independently without being assembled into the device / apparatus / system. The above computer-readable storage medium carries one or more programs, and when the above one or more programs are executed, the method according to the embodiment of the present invention is implemented.

[0094] According to an embodiment of the present invention, the computer-readable storage medium may be a non-volatile computer-readable storage medium. For example, it may include, but is not limited to: a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In the present invention, the computer-readable storage medium may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system, an apparatus or a device.

[0095] For example, according to an embodiment of the present invention, the computer-readable storage medium may include the ROM 302 and / or the RAM 303 described above and / or one or more memories other than the ROM 302 and the RAM 303 .

[0096] The flowcharts and block diagrams in the accompanying drawings illustrate the possible implementation architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present invention. In this regard, each box in the flowchart or block diagram may represent a module, a program segment, or a part of a code, and the above-mentioned module, program segment, or a part of the code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box may also occur in a different order from the order marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of boxes in the block diagram or flowchart, can be implemented with a dedicated hardware-based system that performs the specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions. It can be understood by those skilled in the art that the features recorded in the various embodiments of the present invention can be combined and / or combined in various ways, even if such a combination or combination is not explicitly recorded in the present invention. In particular, without departing from the spirit and teachings of the present invention, the features recorded in the various embodiments of the present invention can be combined and / or combined in various ways. All these combinations and / or combinations fall within the scope of the present invention.

Claims

1. A method for calculating Euler angles, comprising: Get the right ascension and declination corresponding to the specified observation direction of the satellite camera and the first direction vector corresponding to the observation direction of the satellite platform in the inertial orientation mode; Calculating a second direction vector corresponding to the right ascension and the declination includes: according to ， Calculate the second direction vector ,in, Indicates the right ascension of the specified observation direction, Indicates the declination of the specified observation direction, Represents the unit basis vector of the specified observation direction of the satellite camera in the inertial coordinate system or J2000 coordinate system; Calculating a rotation matrix from a specified observation direction to an observation direction of the satellite platform according to the first direction vector and the second direction vector includes: according to ， Calculate the rotation matrix ,in, is the second direction vector, is the first direction vector; The Euler angle of the satellite camera's specified observation direction is calculated according to the rotation matrix.

2. The calculation method according to claim 1, wherein: The calculating the Euler angle of the specified observation direction of the satellite camera according to the rotation matrix specifically includes: Determining a rotation order of a specified observation direction to an observation direction of the satellite platform; Based on the rotation sequence, the Euler angles of the specified observation direction of the satellite camera are calculated according to the rotation matrix, wherein the Euler angles include a pitch angle, a yaw angle, and a roll angle.

3. The calculation method according to claim 2, wherein: The rotation sequences include 12 rotation sequences suitable for aerospace engineering.

4. A Euler angle calculation device, used to execute the method according to claim 1, comprising: An acquisition module, used to acquire the right ascension and declination corresponding to the specified observation direction of the satellite camera and the first direction vector corresponding to the observation direction of the satellite platform; A first calculation module, used for calculating a second direction vector corresponding to the right ascension and the declination; A second calculation module, used for calculating a rotation matrix from a specified observation direction to an observation direction of the satellite platform according to the first direction vector and the second direction vector; The third calculation module is used to calculate the Euler angle of the specified observation direction of the satellite camera according to the rotation matrix.

5. An electronic device, characterized in that: include: one or more processors; A memory for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the method according to any one of claims 1 to 3.

6. A computer-readable storage medium, characterized in that: Executable instructions are stored thereon, and when the instructions are executed by a processor, the processor implements the method according to any one of claims 1 to 3.

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