CN109506656B - High-precision in-orbit attitude information downloading and restoring method - Google Patents

High-precision in-orbit attitude information downloading and restoring method Download PDF

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CN109506656B
CN109506656B CN201811436291.3A CN201811436291A CN109506656B CN 109506656 B CN109506656 B CN 109506656B CN 201811436291 A CN201811436291 A CN 201811436291A CN 109506656 B CN109506656 B CN 109506656B
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star sensor
time
precision
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local clock
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CN109506656A (en
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牛睿
李利亮
蔡陈生
朱琦
朱文山
邵志杰
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Shanghai Aerospace Control Technology Institute
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
    • G01C21/20—Instruments for performing navigational calculations
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
    • G01C21/10—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration
    • G01C21/12—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning
    • G01C21/16—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation
    • G01C21/165—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 by using measurements of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation combined with non-inertial navigation instruments
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
    • G01C21/00—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00
    • G01C21/24—Navigation; Navigational instruments not provided for in groups G01C1/00 - G01C19/00 specially adapted for cosmonautical navigation

Abstract

The invention provides a high-precision on-orbit attitude information downloading and restoring method, which is used for collecting, downloading and restoring information such as original information of a star sensor and an inertial reference unit, effective state words and timestamps thereof at a frequency higher than a control period of satellite-borne software on the ground under the condition of not expanding on-satellite hardware resources. The method is suitable for the condition that the requirement of the load on the update frequency of the satellite attitude is high, but the load is limited by the software operation period or no quick downloading channel.

Description

High-precision in-orbit attitude information downloading and restoring method
Technical Field
The invention relates to a high-precision in-orbit attitude information downloading and restoring method, and belongs to the technical field of satellite-borne software design and attitude data application of a satellite attitude control system.
Background
With the development of civil aerospace technology and application requirements, the requirements for load development technology and data processing are higher and higher. The improvement of the requirements of load spatial resolution and image positioning precision not only puts requirements on the technical development of the load spatial resolution and the image positioning precision, but also needs the improvement of a satellite-ground integrated processing technology.
By adopting the satellite-ground integrated geometric correction processing technology, the remote sensing data is processed on the ground according to the attitude information of the platform, and the influence of factors such as orbit, attitude, deformation and the like on load imaging can be corrected. If a certain high spectral load exists, the spatial resolution is 20-30 m, the image positioning precision is better than 200m, and the satellite-ground integration provides the requirement that the attitude updating rate is not lower than 4Hz for the satellite platform in order to ensure the relative geometric precision in an image scene.
Attitude information required by load image positioning comprises star sensor original data and UTC time at the moment of original data generation. At present, many star sensors do not have the function of providing UTC time, and satellite-borne software is required to process the UTC time according to the acquired single-computer information and the system information and then download the UTC time.
The satellite attitude control system has complex functions, the control period of satellite-borne software is usually 0.5s, and the control period comprises measurement information acquisition, resolving, fault diagnosis, attitude fusion output, control law resolving, system internal and external communication and the like, and in addition, due to the limitation of whole star resources, the original information of the star sensor and the corresponding UTC time are generally downloaded in 16s or 32s updated engineering telemetering, so that the requirement of ground image registration can obviously not be met. At present, a method for solving the problem of slow telemetering and updating speed of attitude information of a star sensor and the like mainly comprises the steps that an LVDS interface is added on a star, and satellite-borne software directly sends data to a data transmission subsystem and downloads the data through a data transmission channel.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: the method overcomes the defects of the prior art, provides a high-precision in-orbit attitude information downloading and restoring method, and meets the requirements of load ground image registration on satellite high-precision attitude updating rate and data precision by time-sharing design of satellite-borne software and design of extraction of core elements in original data of satellite attitude information and a ground restoring method under the conditions that the control period of the satellite-borne software is limited and satellite hardware resources are not suitable to be expanded.
The technical solution of the invention is as follows:
a high-precision on-orbit attitude information downloading and restoring method comprises the following steps:
(1) splitting one running period of the satellite-borne software into odd beats and even beats, wherein the odd beats and the even beats respectively acquire original measurement information of the star sensor and the inertial reference unit; the odd beat and the even beat are respectively 0.25 s;
(2) extracting key parameters in attitude information of the star sensor and the inertial reference unit from the original measurement information; the key parameters include: the method comprises the steps of obtaining an original quaternion of the star sensor, exposure time difference, a local clock of the RTS falling edge moment of the star sensor, a local clock when a last synchronous signal pulse latched by the RTS falling edge moment of the star sensor is sent out, time difference between a system clock and the local clock in a single shot, a star sensor state word, and original measurement information and a state word of an inertia reference unit.
The system clock displays the time of the satellite-borne software, and UTC time is adopted and is consistent with GPS time; the local clock represents the time of the computer hardware system itself, which is used to record the time at which the instructions are sent to the star sensor. The time difference between the system clock and the local clock is constant for one 0.25 s. The state character of the star sensor indicates whether the star sensor is effective currently or not, and is used for judging whether the transmitted quaternion original data are available or not on the ground. The local clock time of the falling edge moment of the RTS signal of the star sensor refers to: and the star-loaded computer sends the latched time when the synchronous pulse is sent to the star sensor.
(3) Storing the key parameters extracted for many times, packaging, and sending the key parameters to the outside through a bus at a preset frequency; the method specifically comprises the following steps: every 0.25s, one group of data is stored in the computer buffer, and every 4 groups of data form a group of source packets which are sent to the data transmission in a period of 1 s.
When composing a source packet, the following steps are carried out:
Figure BDA0001883865520000021
Figure BDA0001883865520000031
(4) and unpacking the received signals by the ground system, and restoring the UTC time corresponding to the original information of the star sensor.
The method specifically comprises the following steps:
(4.1) calculating local clock Tmeas _ a of star sensor exposure time
Figure BDA0001883865520000032
Wherein the offsetRTS＝TRTS_a-Tpps_a，TRTS_aLocal clock time T of star sensor RTS signal falling timepps_aLocal clock time delta T of the sending time of the last synchronous signal latched at the falling edge time of RTS signal of star sensordatation_aThe original exposure time difference of the star sensor is obtained;
(4.2) System clock T for calculating star sensor exposure timess_aSystem clock Tss_aThe UTC time consistent with the ground processing is obtained;
Tss_a＝Tmeas_a+ΔTs，
wherein, Delta TsThe time difference between the system clock and the local clock in a single beat.
Compared with the prior art, the invention has the beneficial effects that:
(1) the method of the invention only needs to utilize the existing bus channel on the satellite without increasing LVDS hardware resources;
(2) the algorithm of the satellite-borne software is simple, too many codes do not need to be added, the control period of the software does not need to be changed, the high-frequency acquisition and transmission of the data of the star sensor and the gyroscope can be realized, and the reliability of the software is not influenced.
Drawings
FIG. 1 is a flow chart of the method of the present invention.
Detailed Description
The following further describes the embodiments of the present invention with reference to the drawings.
As shown in fig. 1, the present invention provides a method for downloading and restoring high-precision on-orbit attitude information, comprising the following steps:
(1) splitting one running period of the satellite-borne software into odd beats and even beats, wherein the odd beats and the even beats respectively acquire original measurement information of the star sensor and the inertial reference unit; the odd beat and the even beat are respectively 0.25 s.
(2) Extracting key parameters in attitude information of the star sensor and the inertial reference unit from the original measurement information; the key parameters include: the method comprises the steps of obtaining an original quaternion of the star sensor, exposure time difference, a local clock of the RTS falling edge moment of the star sensor, a local clock when a last synchronous signal pulse latched by the RTS falling edge moment of the star sensor is sent out, time difference between a system clock and the local clock in a single shot, a star sensor state word, and original measurement information and a state word of an inertia reference unit.
The system clock displays the time of the satellite-borne software, and UTC time is adopted and is consistent with GPS time; the local clock represents the time of the computer hardware system itself, which is used to record the time at which the instructions are sent to the star sensor. The time difference between the system clock and the local clock is constant for one 0.25 s.
The state character of the star sensor indicates whether the star sensor is effective currently or not, and is used for judging whether the transmitted quaternion original data are available or not on the ground.
The local clock time of the falling edge moment of the RTS signal of the star sensor refers to: and the star-loaded computer sends the latched time when the synchronous pulse is sent to the star sensor.
(3) Storing the key parameters extracted for many times, packaging and sending the key parameters to the outside at a preset frequency;
every 0.25s, one group of data is stored in the computer buffer, every 4 groups of data form a group of source packets, and the source packets are sent out in response to 1s period of bus interrupt.
When composing a source packet, the following steps are carried out:
Figure BDA0001883865520000041
Figure BDA0001883865520000051
(4) and unpacking the received signals by the ground system, and restoring the attitude information of the star sensor and the inertial reference unit.
The method specifically comprises the following steps:
(4.1) calculating local clock Tmeas _ a of star sensor exposure time
Figure BDA0001883865520000052
Wherein the offsetRTS＝TRTS_a-Tpps_a，TRTS_aLocal clock time T of star sensor RTS signal falling timepps_aLocal clock time delta T of the sending time of the last synchronous signal latched at the falling edge time of RTS signal of star sensordatation_aIs sensitive to starsThe original exposure time difference of the device;
(4.2) System clock T for calculating star sensor exposure timess_aSystem clock Tss_aThe UTC time consistent with the ground processing is obtained;
Tss_a＝Tmeas_a+ΔTs，
wherein, Delta TsThe time difference between the system clock and the local clock in the single beat is obtained;
and then fusing the data of the star sensors a and b to obtain the direction.
Example (b):
a certain satellite is provided with two imported ASTRO10 star sensors which are named as star sensors a and b respectively. Due to the product design characteristics, the single machine cannot provide the UTC time of the original quaternion generation time, so that the system adds a plurality of clocks in the subsequent key parameter extraction and packaging, and obtains the UTC time of the original quaternion generation time of the star sensors a and b through ground processing.
1. Odd and even beats respectively send RTS signal request data to the star sensors a and b and receive return data;
2. the following key parameters were extracted:
1) time difference Δ Ts between the system clock and the local clock in a single shot: the system clock displays the time of the satellite-borne software, adopts UTC time and keeps consistent with GPS time. The local clock represents the time of the computer hardware system itself, which is used to record the time at which the instructions are sent to the star sensor and to calculate the exposure moveout. Within 0.25s, the time difference between the system clock and the local clock can be considered constant;
2) local clock time T of star sensor a, b RTS signal falling edge momentRTS_a、TRTS_b: the star-loaded computer sends the latching time when the synchronous pulse is sent to the star sensors a and b;
3) local clock time T of the sending time of the last synchronous signal latched at the falling edge time of RTS signals of the star sensors a and bpps_a、Tpps_b；
4) Original exposure time difference delta T of star sensors a and bdatation_a、△Tdatation_b
5) State words of the star sensors a and b: the method comprises the steps that whether a current star sensor is effective or not is indicated, and the method is used for judging whether transmitted quaternion original data are available or not on the ground;
6) original quaternion of star sensors a and b: the satellite-ground integrated processing of one of the main contents is required from the original measured value acquired by the single machine;
7) gyroscope triaxial inertia measurement: the inertial system angular velocity of the currently selected gyroscope is one of main contents required by satellite-ground integrated processing;
8) health status of the top: and the control system utilizes the diagnosis result of the satellite logic on the gyro data to judge whether the transmitted inertial angular velocity is available on the ground.
3. Packaging and sending
And adding a packet head and a packet tail according to the format of the data transmission source packet, and forming a group of data transmission source packets every 1 s.
The package format is as follows:
Figure BDA0001883865520000061
Figure BDA0001883865520000071
4. information reduction
The ground mainly restores the information of the star sensor according to the requirement of the source packet, taking the star sensor a as an example:
1) local clock T for calculating exposure time of star sensormeas_a
Figure BDA0001883865520000072
Offset in equation (1)_RTS＝TRTS_a-Tpps_a
2) System clock T for calculating exposure time of star sensorss_a
Tss_a＝Tmeas_a+ΔTs (2)
System clock Tss_aI.e. UTC time consistent with surface treatment
3) And obtaining the UTC time corresponding to the original quaternion of the star sensor b by the same method, and if more star sensors exist, processing by a similar method.
And then, the data of the star sensors a and b can be fused to obtain high-precision pointing.
In conclusion, through the time sequence planning of the satellite-borne software and the design of key parameters of the star sensor, the method for the time-sharing acquisition and the ground restoration of the high-precision attitude information of the satellite during the in-orbit operation through the software solves the problem that the original data and the time information of the star sensor and the gyroscope can only be downloaded at a low frequency because the original data and the time information are limited by the capability of the satellite-borne software. The method is easy to realize satellite-borne software, makes full use of satellite bus communication resources, and avoids the requirement of hardware LVDS channels.

Claims (8)

1. A high-precision on-orbit attitude information downloading and restoring method is characterized by comprising the following steps:
(1) splitting one running period of the satellite-borne software into odd beats and even beats, wherein the odd beats and the even beats respectively acquire original measurement information of the star sensor and the inertial reference unit;
(2) extracting key parameters in attitude information of the star sensor and the inertial reference unit from the original measurement information; the key parameters include: the method comprises the steps that an original quaternion of a star sensor, an exposure time difference, a local clock of a star sensor RTS falling edge moment, a local clock when a last synchronous signal pulse latched by the star sensor RTS falling edge moment is sent out, the time difference between a system clock and the local clock in a single shot, a star sensor state character, original measurement information of an inertia reference unit and a state character are obtained;
(3) storing the key parameters extracted for many times, packaging, and sending the key parameters to the outside through a bus at a preset frequency;
(4) unpacking the received signals by the ground system, and restoring the UTC time corresponding to the original information of the star sensor; the method specifically comprises the following steps:
(4.1) calculating local clock Tmeas _ a of star sensor exposure time
Figure FDA0002625850090000011
Wherein the offsetRTS＝TRTS_a-Tpps_a，TRTS_aLocal clock time T of star sensor RTS signal falling timepps_aLocal clock time delta T of the sending time of the last synchronous signal latched at the falling edge time of RTS signal of star sensordatation_aThe original exposure time difference of the star sensor is obtained;
(4.2) System clock T for calculating star sensor exposure timess_aSystem clock Tss_aThe UTC time consistent with the ground processing is obtained;
Tss_a＝Tmeas_a+ΔTs，
wherein, Delta TsThe time difference between the system clock and the local clock in a single beat.
2. The method for downloading and restoring high-precision on-orbit attitude information according to claim 1, wherein the method comprises the following steps: the odd beat and the even beat are respectively 0.25 s.
3. The method for downloading and restoring high-precision on-orbit attitude information according to claim 1, wherein the method comprises the following steps: the system clock displays the time of the satellite-borne software, and UTC time is adopted and is consistent with GPS time; the local clock represents the time of the computer hardware system itself, which is used to record the time at which the instructions are sent to the star sensor.
4. The method for downloading and restoring high-precision on-orbit attitude information according to claim 3, wherein the method comprises the following steps: the time difference between the system clock and the local clock is constant for one 0.25 s.
5. The method for downloading and restoring high-precision on-orbit attitude information according to claim 1, wherein the method comprises the following steps: the state character of the star sensor indicates whether the star sensor is effective currently or not, and is used for judging whether the transmitted quaternion original data are available or not on the ground.
6. The method for downloading and restoring high-precision on-orbit attitude information according to claim 1, wherein the method comprises the following steps: the local clock time of the falling edge moment of the RTS signal of the star sensor refers to: and the star-loaded computer sends the latched time when the synchronous pulse is sent to the star sensor.
7. The method for downloading and restoring high-precision on-orbit attitude information according to claim 1, wherein the method comprises the following steps: the step (3) of grouping is performed, and the packet is transmitted to the outside at a preset frequency, and specifically includes: every 0.25s, one group of data is stored in the computer buffer, and every 4 groups of data form a group of source packets which are sent to the data transmission in a period of 1 s.
8. The method for downloading and restoring high-precision on-orbit attitude information according to claim 7, wherein the method comprises the following steps: when composing a source packet, the following steps are carried out:
Figure FDA0002625850090000021
Figure FDA0002625850090000031
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CN112146642A (en) * 2020-09-25 2020-12-29 上海航天控制技术研究所 Three-axis high-precision fiber-optic gyroscope combination for satellite
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CN107065688B (en) * 2017-05-26 2019-04-02 上海航天控制技术研究所 A kind of control method of high-quality satellite platform time synchronization error
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