Star sensor and gyroscope data frequency domain fusion method and system based on complementary filtering

Abstract

The invention discloses a star sensor and gyroscope data frequency domain fusion method and system based on complementary filtering, and belongs to the technical field of spaceflight, and the method comprises the following steps: obtaining a satellite attitude measured by a star sensor and a satellite triaxial angular velocity measured by a gyroscope; converting the triaxial angular velocity of the satellite measured by the gyroscope into a quaternion form; compensating the satellite attitude measured by the star sensor based on the quaternion form of the satellite angular velocity measured by the gyroscope to obtain the quaternion form of the satellite angular velocity measured by the star sensor; fusing the quaternion forms of the satellite angular velocity measured by the star sensor and the satellite angular velocity measured by the gyroscope by adopting a complementary filtering frequency domain fusion method to obtain a fused angular velocity; and performing delay compensation and interpolation on the satellite attitude measured by the star sensor by using the fusion angular velocity to obtain fused satellite attitude data. According to the invention, the data of the star sensor and the gyroscope are fused by adopting a complementary filtering frequency domain fusion method, and a fusion speed with good full-band performance is obtained.

Description

Technical Field

[0001] The present invention belongs to the field of aerospace technology, and particularly relates to a method and system for frequency-domain fusion of star sensor and gyro data based on complementary filtering. Background Art

[0002] In the aerospace field, star sensors are generally used to measure the three-axis attitude information of a satellite, and gyroscopes are used to measure the three-axis angular velocity information of the satellite. However, the measurement frequency of star sensors is relatively low, usually only a few Hertz, and there is a large delay in the output of star sensors, which requires compensation processing for the delay. Gyroscopes can output angular velocity data of several hundred Hertz, but there are drift errors in their measured values, and directly integrating them will cause the error of the attitude angle to increase continuously with time. Currently, the common practice is to combine the measurement information of star sensors and gyroscopes to form an attitude estimator, and use the measured value of the star sensor as a reference to correct the gyro drift error, thereby improving the accuracy of satellite attitude information. However, it is difficult to balance the timing of correcting gyro data by star sensors. If the correction frequency is high, it will cause frequent jumps in attitude information, affecting stability; if the correction frequency is low, more gyro drift errors will be introduced, affecting attitude accuracy. And when the measurement accuracy of the gyro deteriorates, especially when the drift increases, the performance of this method deteriorates significantly.

[0003] In an optoelectronic tracking system, a two-dimensional turntable needs to obtain the attitude information of the satellite platform, so as to calculate the azimuth angle and elevation angle that it needs to rotate. To ensure tracking accuracy, the output frequency of satellite attitude information needs to reach at least 100 Hz or more, and there must also be high speed stability to ensure optical imaging. However, the Kalman filter fusion algorithm, which is widely used in engineering practice, is limited by the linearization assumption. During the satellite attitude maneuvering process, its fusion accuracy of star sensor and gyro data deteriorates and it is difficult to meet the requirements. Moreover, the Kalman filter fusion algorithm is computationally complex and difficult to implement on some low-computing-power chips.

[0004] The existing technologies have the following problems and deficiencies: 1) In the existing technology, the gyro integration is usually used to estimate the attitude information. Although the star sensor is used to correct the integration, it is difficult to grasp the correction frequency, and when the gyro drift becomes larger, the fusion result deteriorates significantly.

[0005] 2) In the existing technology, the least squares method is used to perform weighted fusion on the data of the star sensor and the gyro, but in essence, it will still introduce the influence of gyro drift integration, reducing the robustness of the fusion method.

[0006] 3) In the existing technology, the influence brought by the output delay of the star sensor is not considered, resulting in obvious lag errors in the fused attitude information.

[0007] 4) The existing data fusion algorithm based on Kalman filtering has a large computational load and requires the assumption that the system is linear, making it difficult to apply in real-time attitude solution.

[0008] Therefore, it is of great practical significance to design a data fusion algorithm for star sensors and gyroscopes that is simple to calculate, has few assumption limitations, and has excellent fusion performance. Summary of the Invention

[0009] The purpose of the present invention is to provide a frequency-domain fusion method and system for star sensor and gyroscope data based on complementary filtering, so as to solve the technical problems existing in the prior art, such as the difficulty in determining the correction frequency when fusing star sensor and gyroscope data, obvious lag error in the fused attitude information, and large computational load.

[0010] To achieve the above purpose, the present invention adopts the following technical solutions: In the first aspect, the present invention provides a frequency-domain fusion method for star sensor and gyroscope data based on complementary filtering, including: Obtain the satellite attitude measured by the star sensor and the satellite three-axis angular velocity measured by the gyroscope; Convert the satellite three-axis angular velocity measured by the gyroscope into the form of quaternion through the attitude kinematic equation; Compensate the satellite attitude measured by the star sensor based on the quaternion form of the satellite angular velocity measured by the gyroscope to obtain the quaternion form of the satellite angular velocity measured by the star sensor; Adopt the complementary filtering frequency-domain fusion method to fuse the quaternion form of the satellite angular velocity measured by the star sensor and the quaternion form of the satellite angular velocity measured by the gyroscope to obtain the fused angular velocity; Use the fused angular velocity to perform delay compensation and interpolation on the satellite attitude measured by the star sensor to obtain the fused satellite attitude data.

[0011] Further, the satellite three-axis angular velocity measured by the gyroscope is converted into the form of quaternion through the following formula: ; In the formula, is the quaternion form of the satellite angular velocity measured by the gyroscope in the k-th frame, is a fourth-order skew-symmetric matrix, is the satellite three-axis angular velocity measured by the gyroscope, represents the quaternion of the fused satellite attitude in the (k - 1)-th frame.

[0012] Further, the formula for compensating the satellite attitude measured by the star sensor based on the quaternion form of the satellite angular velocity measured by the gyroscope to obtain the quaternion form of the satellite angular velocity measured by the star sensor is:

[0013] In the formula is the quaternion form of the satellite angular velocity data measured by the star sensor in the k th frame; is the quaternion form of the satellite acceleration measured by the gyroscope in the th frame, and respectively represent the sampling periods of the star sensor and the gyroscope; k is the quaternion form of the satellite acceleration measured by the gyroscope in the th frame, which is obtained by differentiating the quaternion form of the satellite angular velocity data measured by the gyroscope. The calculation formula is ; is the number of steps for star sensor delay compensation, where is the output delay of the star sensor; int() is the floor operator;

[0014] Furthermore, the fusion of the star sensor angular velocity and the gyroscope angular velocity data by using the complementary filtering frequency domain fusion method is realized by the following formula:

[0015] In the formula, is the output data of the corrector in the k th frame; is the fused angular velocity in the k th frame; is the proportional coefficient of the PI corrector; is the integral coefficient of the PI corrector, is the sampling period of the gyroscope, is the quaternion form of the satellite angular velocity measured by the gyroscope in the th frame, , representing the difference between the star sensor angular velocity and the fused angular velocity at the k -1th frame, is the star sensor angular velocity data in the k -1th frame; is the fused angular velocity data in the -1th frame; k , representing the difference between the star sensor angular velocity and the fused angular velocity at the -2th frame,

[0016] Furthermore, the use of the fused angular velocity to perform delay compensation and interpolation on the satellite attitude measured by the star sensor to obtain the fused satellite attitude data includes: When the star sensor is updated, based on the attitude data output by the star sensor, the delay is compensated with the fused angular velocity data to obtain the fused satellite attitude data; When the star sensor is not updated, the attitude information is interpolated at the fused angular velocity to obtain the fused satellite attitude data.

[0017] Furthermore, the recurrence formula for the fused satellite attitude data is:

[0018] In the formula, is the fused satellite attitude data for the k th frame; is the star sensor delay compensation step number, where is the star sensor output delay; int() is the floor operator; .

[0019] In a second aspect, the present invention provides a star sensor and gyro data frequency domain fusion system based on complementary filtering, including: An acquisition module for acquiring the satellite attitude measured by the star sensor and the satellite three-axis angular velocity measured by the gyro; A conversion module for converting the satellite three-axis angular velocity measured by the gyro into a quaternion form through the attitude kinematic equation; A delay compensation module for compensating the satellite attitude measured by the star sensor based on the quaternion form of the satellite angular velocity measured by the gyro to obtain the quaternion form of the satellite angular velocity measured by the star sensor; A fusion module for fusing the quaternion form of the satellite angular velocity measured by the star sensor and the quaternion form of the satellite angular velocity measured by the gyro by using a complementary filtering frequency domain fusion method to obtain a fused angular velocity; A calculation module for performing delay compensation and interpolation on the satellite attitude measured by the star sensor using the fused angular velocity to obtain the fused satellite attitude data.

[0020] In a third aspect, the present invention provides an electronic device, including: At least one processor; and, A memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute a star sensor and gyro data frequency domain fusion method according to any one of the first aspects of the present invention.

[0021] In a fourth aspect, the present invention provides a computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, it implements a star sensor and gyro data frequency domain fusion method according to any one of the first aspects of the present invention.

[0022] In a fifth aspect, the present invention provides a computer program product, including a computer program, which, when executed by a processor, implements the steps of a method for frequency-domain fusion of star sensor and gyro data based on complementary filtering according to any one of the first aspects of the present invention.

[0023] Compared with the prior art, the present invention has at least the following beneficial technical effects: 1) The present invention uses a complementary filtering method for frequency-domain fusion of star sensor and gyro data, and simultaneously processes high-frequency gyro signals and low-frequency star sensor signals through frequency-domain design, avoiding the performance degradation of traditional filters in specific frequency bands. For example, the Kalman filter has poor processing effect on high-frequency signals and it is difficult to maintain consistency in the full frequency band; wavelet transform may have energy leakage or distortion in some frequency bands. In addition, the frequency-domain fusion method adopted by the present invention can effectively separate noise and signals through frequency-domain design, and has stronger anti-noise ability. The present invention takes the attitude information collected by the star sensor as a reference, and uses the fused angular velocity for delay compensation and attitude prediction, improving the bandwidth and accuracy of the fused signal; It avoids problems such as many assumption limitations, complex calculations, and sensitivity to initial values in existing data fusion algorithms, making the star sensor and gyro data fusion algorithm applicable to real-time attitude solution of satellites; the principle of the data fusion algorithm is simple, the physical meaning of parameters is clear, and it has simple and reliable engineering feasibility.

[0024] 2) The method for frequency-domain fusion of star sensor and gyro data proposed by the present invention can not only obtain the fused satellite attitude information, but also obtain the fused angular velocity information, avoiding the drift error introduced when directly integrating the gyro measurement values.

[0025] 3) Compared with the existing star sensor and gyro fusion method based on least squares, this method uses the angular velocity information measured by the gyro to compensate for the delay of the star sensor, reducing the lag error of the fusion result; 4) Compared with the existing fusion method based on Kalman filter, the frequency-domain fusion method proposed by the present invention has a small amount of calculation, simple engineering implementation, and does not depend on an accurate system model. And the frequency-domain fusion method is flexibly designed and can adjust the frequency-domain response according to requirements to adapt to different application scenarios. Description of the Drawings

[0026] Figure 1 It is a schematic flow diagram of the method for frequency-domain fusion of star sensor and gyro based on complementary filtering; Figure 2 It is a comparison diagram of the angular velocity of the star sensor and the fused angular velocity; Figure 3 It is a comparison of the attitude measured by the star sensor, the attitude fused by the gyro, and the attitude fused in the frequency domain; Figure 4The structural block diagram of a star sensor and gyro data frequency domain fusion system based on complementary filtering provided by an embodiment of the present invention; Figure 5 The block diagram of an electronic device according to an embodiment of the present invention. Specific embodiments

[0027] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0028] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0029] The present invention will be further described in detail below with reference to the accompanying drawings: Embodiment 1 This embodiment provides a star sensor and gyro data frequency domain fusion method based on complementary filtering, which provides satellite platform attitude information with real-time performance, high bandwidth and high precision for an optoelectronic tracking system. The method includes the following steps: Step 1: Convert the satellite three-axis angular velocity measured by the gyro into a quaternion form, then differentiate the satellite attitude measured by the star sensor, and use the quaternion form of the satellite angular velocity measured by the gyro for delay compensation and interpolation to obtain the satellite angular velocity information measured by the star sensor.

[0030] The satellite attitude is usually described by quaternions. Assume that the k satellite attitude measured by the star sensor in the k-th frame is ; the satellite three-axis angular velocity measured by the gyro is . According to the satellite attitude kinematic equation, we can get: ; where is the quaternion form of the satellite angular velocity measured by the gyro in the k-th frame. is a fourth-order skew-symmetric matrix, which is the satellite's three-axis angular velocity measured by the gyroscope, representing the satellite attitude quaternion after fusion in the (k - 1)-th frame.

[0031] Since the star sensor has a low measurement frequency and a large delay, the angular velocity information measured by the gyroscope is used for delay compensation and angular velocity interpolation. Finally, the angular velocity value of the star sensor is obtained as: (1) In the formula, is the quaternion form of the satellite angular velocity measured by the star sensor in the k -th frame; is the quaternion form of the satellite acceleration measured by the gyroscope in the i-th frame, and represent the sampling periods of the star sensor and the gyroscope respectively; is the quaternion form of the satellite acceleration measured by the gyroscope in the k -th frame, which is obtained by differentiating the satellite angular velocity data measured by the gyroscope. The calculation formula is ; is the number of steps for star sensor delay compensation, where is the output delay of the star sensor; int() is the floor operator; .

[0032] Step 2: Adopt a complementary filtering frequency-domain fusion method to fuse the angular velocity data measured by the star sensor and the gyroscope. Its structure is as Figure 1 shown. Utilize the low-pass following characteristic of the feedback system to extract the low-frequency part of the angular velocity data of the star sensor with a lower bandwidth, and utilize the high-pass characteristic to extract the high-frequency part of the angular velocity data of the gyroscope with a higher bandwidth. The two are superimposed to obtain an angular fusion velocity output with excellent performance in the full frequency band. The core is the selection of the fusion corrector. In the present invention, a proportional-integral (PI) corrector is used. By adjusting the proportional-integral coefficients of the PI corrector, the bandwidth and accuracy of the fused angular velocity signal are adjusted. The recurrence formula for the fused angular velocity is as follows: (2) In the formula, is the output data of the corrector in the k -th frame; is the fused angular velocity data in the k -th frame; is the proportional coefficient of the PI corrector; is the integral coefficient of the PI corrector, , representing the difference between the angular velocity of the star sensor and the fused angular velocity at the (k - 1)-th frame, is in the kThe quaternion form of the satellite angular velocity measured by the star sensor at frame k-1; is the k fused angular velocity data at frame k-1; , indicating the difference between the angular velocity of the star sensor and the fused angular velocity at frame k-2; is the k quaternion form of the satellite angular velocity measured by the star sensor at frame k-2; is the fused angular velocity data at frame k-2.

[0033] So far, a fused satellite platform angular velocity data can be obtained. The fused angular velocity signal solves the problem of the time delay of the star sensor angular velocity signal, and the fused angular velocity signal retains the accuracy of the angular velocity signal directly measured by the gyro. Next, the attitude information of the satellite platform can be calculated using the fused angular velocity.

[0034] Step 3: The satellite platform attitude signal measured by the star sensor has problems of large time delay and low frame rate. To address this problem, the fused angular velocity data obtained in the above steps is used for time delay compensation and interpolation, so as to obtain a satellite attitude signal with real-time performance and high frame rate.

[0035] The specific process is as follows: When the star sensor is updated, based on the attitude data output by the star sensor, the time delay is compensated using the fused angular velocity data to obtain the fused satellite attitude data; When the star sensor is not updated, the attitude information is interpolated using the fused angular velocity to obtain the fused satellite attitude data. The recurrence formula for the fused satellite platform attitude signal is as follows: (3) In the formula, is the k fused satellite attitude data at frame k; is the number of steps for star sensor time delay compensation, where is the output time delay of the star sensor; int() is the floor operator; ;.

[0036] The method for frequency domain fusion of star sensor and gyro data based on complementary filtering proposed by the present invention can be made applicable to the fusion of sensors with different characteristics by designing different correctors. For example, for sensors such as star sensors and accelerometers that are accurate for low-frequency signals and have large high-frequency noise, a corrector with low-pass characteristics is designed to suppress high-frequency noise; for sensors such as gyros that are accurate for high-frequency signals and have large low-frequency drift, a corrector with high-pass characteristics is designed to suppress low-frequency drift. Therefore, any improvement and application of the proposed fusion method achieved by adjusting the corrector parameters fall within the scope of protection of this patent.

[0037] The method for frequency-domain fusion of star sensor and gyro data based on complementary filtering proposed by the present invention is a general sensor information fusion method. Therefore, applying this fusion method to the fusion of other types of sensors falls within the protection scope of this patent.

[0038] The fusion method proposed by the present invention can be implemented on various platforms such as embedded hardware, chips, PLCs, and computers. Therefore, its implementation on any hardware platform falls within the protection scope of this patent.

[0039] Specific application examples This embodiment is implemented on the premise of the technical solution of the present invention, and gives a detailed implementation manner and specific operation process. However, the protection scope of the present invention is not limited to the following embodiments.

[0040] This embodiment illustrates the implementation process of the present invention in combination with the measurement characteristics of the star sensor and the gyro. Assume that the attitude quaternion of the satellite platform changes as follows: (4) Taking a common star sensor as an example, its sampling frequency is 4 Hz, the delay is 250 ms, and the influence of measurement noise is considered. The actual output of the star sensor is: (5) In the formula, represents the measurement noise, assumed to be Gaussian white noise with a standard deviation of 0.0005.

[0041] Taking a certain type of fiber optic gyro as an example, its sampling frequency is 200 Hz. Considering that the angular velocity random walk coefficient is , h represents hours, the angle random walk coefficient is , the scale factor non-linearity is 50 ppm, and the zero bias repeatability is . The quaternion form of the angular velocity measured by the fiber optic gyro is: (6) In the formula, represents the gyro drift, and represent the measurement noise, which is related to the random walk coefficient.

[0042] This embodiment includes the following steps: 1) Differentiate the output of the star sensor to obtain the angular velocity information. Due to the delay and low output frequency of the star sensor, the angular velocity measured by the gyro is used for delay compensation and angular velocity interpolation. Finally, the discretized satellite angular velocity value measured by the star sensor is: (7) In the formula, is the quaternion form of the satellite acceleration measured by the gyro for the k frame, which is obtained by differentiating the quaternion form of the satellite angular velocity measured by the gyro. The calculation formula is . is the output of the star sensor for the k frame; is the quaternion form of the satellite angular velocity measured by the star sensor for the k -1 frame; 2) Adopt the complementary filtering frequency domain fusion method to fuse the angular velocity information measured by the star sensor and the gyro. The proportional coefficient of the PI corrector is designed to be 0.01, and the integral coefficient is designed to be 0.018. The recurrence formula for the fused angular velocity is as follows: (8) where is the output value of the corrector for the k frame; is the quaternion form of the satellite angular velocity measured by the star sensor for the k -1 frame; is the fused angular velocity for the k frame; is the quaternion form of the satellite angular velocity measured by the fiber optic gyro for the k frame; 3) Use the fused angular velocity data obtained above to perform delay compensation and interpolation on the output of the star sensor. When the star sensor is updated, based on the attitude data output by the star sensor, use the fused angular velocity data to compensate for the delay to obtain the fused satellite attitude data; when the star sensor is not updated, interpolate the attitude information with the fused angular velocity to obtain the fused satellite attitude data. The recurrence formula for the fused attitude signal is as follows: (9) where is the fused satellite attitude data for the k frame; is the fused angular velocity data for the i-th frame; is for the k frame of fused angular velocity data.

[0043] The simulation step size is set to 0.005 s. The comparison results of the fused angular velocity and the angular velocity directly differentiated from the star sensor are shown in the appendix Figure 2 . The angular velocity error directly differentiated from the star sensor is 0.0064 (1σ), and the angular velocity error of the fusion is 0.0047 (1σ). The fused angular velocity obtained by the method proposed in the present invention compensates for the output delay of the star sensor, and the accuracy is significantly improved.

[0044] The comparison results of the method proposed in the present invention, which fuses the attitude measured by the star sensor and the attitude measured by gyroscopes (directly using the angular velocity measured by the gyroscopes to perform delay compensation and interpolation on the output of the star sensor), are as follows in the appendix Figure 3 . The error of the attitude measured by the star sensor is 0.21525 (1σ), the error of the attitude fused by gyroscopes is 0.00025 (1σ), and the error of the frequency-domain fusion is 0.00024 (1σ). It can be seen that both gyroscope fusion and frequency-domain fusion can significantly improve the accuracy of the satellite attitude signal

[0045] However, the method of fusing gyroscope attitudes depends severely on the measurement accuracy of gyroscopes. When the gyroscope drift becomes larger, the accuracy of this method decreases significantly. While the frequency-domain fusion method proposed in the present invention can still maintain a high fusion accuracy. To compare the actual effects, the angular random walk coefficient of the gyroscope is increased. At this time, the error of the attitude fused by gyroscopes is 0.00147 (1σ), and the error of the frequency-domain fusion is 0.00087 (1σ). It can be seen that when the measurement accuracy of the gyroscope deteriorates, the frequency-domain fusion method proposed in the present invention has a better effect than direct gyroscope fusion

[0046] Example 2 Please refer to Figure 4 . In this embodiment, a frequency-domain fusion system for star sensor and gyroscope data based on complementary filtering is provided, including: An acquisition module, configured to acquire the satellite attitude measured by the star sensor and the satellite three-axis angular velocity measured by the gyroscope A conversion module, configured to convert the satellite three-axis angular velocity measured by the gyroscope into the form of quaternion through the attitude kinematic equation A delay compensation module, configured to compensate the satellite attitude measured by the star sensor based on the quaternion form of the satellite angular velocity measured by the gyroscope to obtain the quaternion form of the satellite angular velocity measured by the star sensor A fusion module, configured to fuse the quaternion form of the satellite angular velocity measured by the star sensor and the quaternion form of the satellite angular velocity measured by the gyroscope by using the complementary filtering frequency-domain fusion method to obtain a fused angular velocity A calculation module, configured to perform delay compensation and interpolation on the satellite attitude measured by the star sensor by using the fused angular velocity to obtain the fused satellite attitude data

[0047] All the relevant contents of each step involved in the embodiment of the foregoing frequency-domain fusion method for star sensor and gyroscope data based on complementary filtering can be cited in the function descriptions of the corresponding functional modules of a frequency-domain fusion system for star sensor and gyroscope data based on complementary filtering in the embodiment of the present invention, and will not be elaborated herein

[0048] Example 3 Refer to Figure 5, this embodiment provides an electronic device, which includes a processor and a memory. The processor is connected to the memory through a bus. The memory is used to store a computer program, and the computer program includes program instructions. The processor is used to execute the program instructions stored in the computer storage medium. The processor may be a central processing unit (CPU), or may also be other general-purpose processors, digital signal processors (DSPs), application specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. It is the computing core and control core of the terminal, and is suitable for implementing one or more instructions. Specifically, it is suitable for loading and executing one or more instructions in the computer storage medium to implement the corresponding method flow or corresponding function. The processor described in the embodiment of the present invention can be used for the operation of a star sensor and gyro data frequency domain fusion method based on complementary filtering. The bus may be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For the sake of convenience of representation, Figure 5 only one line is used to represent it in [description], but it does not mean that there is only one bus or one type of bus.

[0049] Embodiment 4 This embodiment provides a storage medium, specifically a computer-readable storage medium (Memory). The computer-readable storage medium is a memory device in an electronic device and is used to store programs and data. It can be understood that the computer-readable storage medium here can include both the built-in storage medium in the electronic device and, of course, the extended storage medium supported by the electronic device. The computer-readable storage medium provides a storage space, and this storage space stores the operating system of the terminal. Moreover, one or more instructions suitable for being loaded and executed by the processor are stored in this storage space, and these instructions can be one or more computer programs (including program codes). It should be noted that the computer-readable storage medium here can be a high-speed RAM memory or a non-volatile memory, such as at least one disk memory. One or more instructions stored in the computer-readable storage medium can be loaded and executed by the processor to implement the corresponding steps in the above-mentioned embodiment regarding a method for frequency-domain fusion of star sensor and gyro data based on complementary filtering.

[0050] Those skilled in the art should understand that the embodiments of the present application can be provided as a method, a system, or a computer program product. Therefore, the present application can take the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware aspects. Moreover, the present application can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk memories, CD-ROMs, optical memories, etc.) containing computer-usable program codes.

[0051] The present application is described with reference to the flowcharts and / or block diagrams of methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each flow and / or block in the flowchart and / or block diagram, as well as the combination of flows and / or blocks in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to the processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing devices to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing devices generate a device for implementing the functions specified in Figure 1 one flow or multiple flows and / or blocks Figure 1 one block or multiple blocks.

[0052] These computer program instructions can also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer-readable memory generate a manufactured article including an instruction device, and the instruction device implements the functions in Figure 1 one flow or multiple flows and / or blocks Figure 1The functions specified in one or more boxes.

[0053] These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to generate a computer-implemented process. Thus, the instructions executed on the computer or other programmable device provide for implementing the steps of the functions specified in Figure 1 one process or more processes and / or boxes Figure 1 the steps of the functions specified in one box or more boxes.

[0054] Embodiment 5 This embodiment provides a computer program product, including a non-volatile computer-readable storage medium. The non-volatile computer-readable storage medium stores a computer program product. When the computer program is executed by a processor, it implements the steps of the methods described in various embodiments of the present application.

[0055] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data for analysis, stored data, displayed data, etc.) involved in the present application are all information and data authorized by the user or fully authorized by all parties. And the collection, use, and processing of relevant data need to comply with the relevant laws, regulations, and standards of relevant countries and regions.

[0056] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0057] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that: It is still possible to modify the specific implementation manners of the present invention or make equivalent replacements. Any modification or equivalent replacement without departing from the spirit and scope of the present invention should be covered by the protection scope of the claims of the present invention.

Claims

1. A method for frequency-domain fusion of star sensor and gyro data based on complementary filtering, characterized in that Comprising: Obtain the satellite attitude measured by the star sensor and the satellite three-axis angular velocity measured by the gyroscope; Convert the satellite three-axis angular velocity measured by the gyroscope into quaternion form through the attitude kinematic equation; Compensate the satellite attitude measured by the star sensor based on the quaternion form of the satellite angular velocity measured by the gyroscope to obtain the quaternion form of the satellite angular velocity measured by the star sensor; Adopt the complementary filtering frequency-domain fusion method to fuse the quaternion form of the satellite angular velocity measured by the star sensor and the quaternion form of the satellite angular velocity measured by the gyroscope to obtain the fused angular velocity; Use the fused angular velocity to perform delay compensation and interpolation on the satellite attitude measured by the star sensor to obtain the fused satellite attitude data.

2. A frequency domain fusion method for star sensor and gyro data based on complementary filtering according to claim 1, characterized in that Convert the satellite three-axis angular velocity measured by the gyroscope into quaternion form through the following formula: ； wherein, is the quaternion form of the satellite angular velocity measured by the gyroscope at the k-th frame, is a fourth-order skew-symmetric matrix, is the three-axis angular velocity of the satellite measured by the gyroscope, represents the quaternion of the satellite attitude after fusion at the (k-1)-th frame.

3. A star sensor and gyro data frequency domain fusion method based on complementary filtering according to claim 1, characterized in that The formula for compensating the satellite attitude measured by the star sensor based on the quaternion form of the satellite angular velocity measured by the gyroscope to obtain the quaternion form of the satellite angular velocity measured by the star sensor is: In the formula, is the quaternion form of the satellite angular velocity measured by the star sensor in the k th frame; is the quaternion form of the satellite attitude measured by the star sensor in the k th frame; is the quaternion form of the satellite acceleration measured by the gyroscope in the i-th frame, and respectively represent the sampling periods of the star sensor and the gyroscope; is the quaternion form of the satellite acceleration measured by the gyroscope in the k th frame, obtained by differentiating the quaternion form of the satellite angular velocity measured by the gyroscope. The calculation formula is ; is the number of steps for star sensor delay compensation, where is the output delay of the star sensor; int() is the floor operator; .

4. A method for frequency-domain fusion of star sensor and gyro data based on complementary filtering according to claim 1, characterized in that The complementary filtering frequency-domain fusion method for fusing the star sensor angular velocity and the gyro angular velocity data is implemented through the following formula: Wherein, is the output data of the k frame corrector; is the k frame fusion angular velocity; is the proportionality coefficient of the PI corrector; is the integral coefficient of the PI corrector, is the sampling period of the gyroscope, is the quaternion form of the satellite angular velocity measured by the gyroscope at the k-th frame, , indicating the difference between the star sensor angular velocity and the fusion angular velocity at the (k - 1)-th frame, is the k star sensor angular velocity data at the (k - 1)-th frame; is the k fusion angular velocity data at the (k - 1)-th frame; , indicating the difference between the star sensor angular velocity and the fusion angular velocity at the (k - 2)-th frame, is the k star sensor angular velocity data at the (k - 2)-th frame; is the fusion angular velocity data at the (k - 2)-th frame.

5. A method for frequency-domain fusion of star sensor and gyro data based on complementary filtering according to claim 1, characterized in that, Using the fused angular velocity to perform delay compensation and interpolation on the satellite attitude measured by the star sensor to obtain the fused satellite attitude data includes: When the star sensor is updated, based on the attitude data output by the star sensor, compensate for the delay with the fused angular velocity data to obtain the fused satellite attitude data; When the star sensor is not updated, interpolate the attitude information with the fused angular velocity to obtain the fused satellite attitude data.

6. According to the method for frequency-domain fusion of star sensor and gyro data based on complementary filtering described in claim 5, the recurrence formula for the fused satellite attitude data is: In the formula, is the satellite attitude data after frame fusion of the k th frame; is the number of steps for star sensor delay compensation, where is the output delay of the star sensor; int() is the floor operator; .

7. A star sensor and gyro data frequency domain fusion system based on complementary filtering, characterized in that, Comprising: An acquisition module for acquiring the satellite attitude measured by the star sensor and the satellite three-axis angular velocity measured by the gyroscope; A conversion module for converting the satellite three-axis angular velocity measured by the gyroscope into quaternion form through the attitude kinematic equation; A delay compensation module for compensating the satellite attitude measured by the star sensor based on the quaternion form of the satellite angular velocity measured by the gyroscope to obtain the quaternion form of the satellite angular velocity measured by the star sensor; A fusion module for fusing the quaternion form of the satellite angular velocity measured by the star sensor and the quaternion form of the satellite angular velocity measured by the gyroscope by adopting the complementary filtering frequency-domain fusion method to obtain the fused angular velocity; A calculation module for using the fused angular velocity to perform delay compensation and interpolation on the satellite attitude measured by the star sensor to obtain the fused satellite attitude data.

8. An electronic device, characterized in that, Comprising: At least one processor; And, A memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute a method for frequency-domain fusion of star sensor and gyro data based on complementary filtering as described in any one of claims 1 to 6.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements a method for frequency-domain fusion of star sensor and gyro data based on complementary filtering as described in any one of claims 1 to 6.

10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the steps of a frequency-domain fusion method for star sensor and gyro data based on complementary filtering according to any one of claims 1 to 6.

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