阅读说明：本技术 一种基于加速度计组合的高精度编队控制方法 (High-precision formation control method based on accelerometer combination ) 是由 陈筠力 王文妍 杜耀珂 陈桦 完备 刘美师 崔佳 王嘉轶 王禹 朱郁婓 龚腾上 于 2020-03-20 设计创作，主要内容包括：一种基于加速度计组合的高精度编队控制方法,采用加速度计接入控制回路实时测量星体加速度,通过预估加速度计漂移补偿参数,控制过程动态获取推力器标定系数,实现编队控制量动态反馈与修正,不受执行机构配置条件限制,同时能够在星上自主实现,解决了现有技术中难以实现在不同构形尺度及控制任务工况条件下的编队卫星高精度控制问题,更贴合工程实际,适用范围更广。(A high-precision formation control method based on accelerometer combination measures the acceleration of a star body in real time by adopting an accelerometer access control loop, dynamically acquires a thruster calibration coefficient in a control process by predicting the drift compensation parameter of the accelerometer, realizes dynamic feedback and correction of formation control quantity, is not limited by the configuration condition of an actuating mechanism, can be independently realized on the star, solves the problem that the high-precision control of formation satellites under different configuration scales and control task working conditions is difficult to realize in the prior art, is more suitable for engineering practice, and has wider application range.)

1. A high-precision formation control method based on accelerometer combination is characterized by comprising the following steps:

(1) calculating the control quantity of formation control according to a control strategy, wherein the control quantity of formation control comprises a speed increment delta vc, an air injection time length L t and an air injection starting time Tp, and calculating accelerometer drift compensation parameters according to accelerometer measurement data from a period of time before the air injection starting time to the Tp;

(2) presetting an instruction splitting coefficient, splitting the formation control air injection instruction according to the instruction splitting coefficient to obtain two formation control instructions;

(3) executing the split first formation control instruction obtained in the step (2), and autonomously calculating an actual speed increment delta vr1 and a thruster efficiency coefficient K corresponding to the first formation control instruction according to the measurement result of the accelerometer after the execution is finished;

(4) and (4) correcting the air injection time length of the second formation control instruction according to the thruster efficiency coefficient K calculated in the step (3), and continuously executing the formation control instruction according to the corrected air injection time length to complete the formation satellite control.

2. The high-precision formation control method based on the accelerometer combination as claimed in claim 1, wherein: in the step (1), a calculation formula for calculating the accelerometer drift compensation parameter according to the accelerometer measurement data from a period of time before the jet start time to the Tp time is as follows:

b＝Δv_IMU/T_IMU

where b is the accelerometer drift compensation parameter, T_IMUIntegrating time, here the time interval from a time preceding Tp to time Tp, Δ v, is output for acceleration combining_IMUIs at T_IMUThe internal accelerometer combines the velocity increments of the output.

3. The high-precision formation control method based on the accelerometer combination as claimed in claim 1, wherein: in the step (2), the instruction splitting coefficient c is determined according to the measurement precision of the accelerometer and the precision of the thruster, the obtained formation control instructions are split, the first instruction is combined and measured in real time by the accelerometer in the execution process, the speed increment obtained through actual measurement is compared with a theoretical calculated value after the execution is finished, the actual efficiency of the thruster is obtained, the efficiency of the thruster obtained in the execution process of the second instruction is introduced to recalculate the instruction duration, the total speed increment of the two instructions is equal to the theoretical speed increment, the control precision is improved, the splitting coefficient is smaller when the precision of the thruster is poor or the measurement precision of the combination of the accelerometer is higher, otherwise, the splitting coefficient is larger when the precision of the thruster is good or the measurement precision of the combination of the accelerometer is lower, wherein the formation instruction duration and the splitting method of the speed increment are:

Lt1＝c*Lt；Lt2＝(1-c)*Lt

Δvc1＝c*Δvc；Δvc2＝(1-c)*Δvc

wherein L t1 is a first control command duration, L t2 is a second control command duration, Δ vc1 is a first control theoretical speed increment, and Δ vc2 is a second control theoretical speed increment.

4. The high-precision formation control method based on the accelerometer combination as claimed in claim 1, wherein: in the step (3), the method for calculating the actual speed increment Δ vr1 and the thruster efficiency coefficient K of the formation satellite in the first control process according to the combined measurement result of the accelerometer specifically comprises the following steps:

Δvr1＝Δv1_IMU-bLt1

K＝Δvr1/Δvc1

wherein, Δ v1_IMUThe measurements are combined for the accelerometer over the L t1 time period.

5. The high-precision formation control method based on the accelerometer combination as claimed in claim 1, wherein: in the step (4), the specific method for correcting the instruction duration of the formation execution control instruction is as follows:

Lt2c＝Lt1/K-Lt1+Lt2/K

wherein L t2c is the modified queue execution control instruction duration.

Technical Field

The invention relates to a high-precision formation control method based on accelerometer combination, and belongs to the technical field of satellite formation control.

Background

With the gradual turning engineering application of the satellite formation flight technology in the fields of earth observation, astronomical observation and the like, the engineering technology system for formation control is gradually refined and deepened. Due to the fact that the task requirements are improved, the requirement on formation control accuracy is higher and higher, and meanwhile the geometric dimension of formation configuration is greatly changed from several kilometers to hundreds of meters. In order to ensure that high-precision formation control can be realized under the conditions of large scale and large control quantity, a simple and effective high-precision formation control method needs to be designed on the basis of the existing engineering capacity.

Disclosure of Invention

The technical problem solved by the invention is as follows: aiming at the problem that high-precision control of formation satellites under large-range and configuration conditions is difficult to realize in the prior art, a high-precision formation control method based on accelerometer combination is provided.

The technical scheme for solving the technical problems is as follows:

a high-precision formation control method based on accelerometer combination comprises the following steps:

(1) calculating the control quantity of formation control according to a control strategy, wherein the control quantity of formation control comprises a speed increment delta vc, an air injection time length L t and an air injection starting time Tp, and calculating accelerometer drift compensation parameters according to accelerometer measurement data from a period of time before the air injection starting time to the Tp;

(2) presetting an instruction splitting coefficient, splitting the formation control air injection instruction according to the instruction splitting coefficient to obtain two formation control instructions;

(3) executing the split first formation control instruction obtained in the step (2), and autonomously calculating an actual speed increment delta vr1 and a thruster efficiency coefficient K corresponding to the first formation control instruction according to the measurement result of the accelerometer after the execution is finished;

(4) and (4) correcting the air injection time length of the second formation control instruction according to the thruster efficiency coefficient K calculated in the step (3), and continuously executing the formation control instruction according to the corrected air injection time length to complete the formation satellite control.

In the step (1), a calculation formula for calculating the accelerometer drift compensation parameter according to the accelerometer measurement data from a period of time before the jet start time to the Tp time is as follows:

b＝Δv_IMU/T_IMU

where b is the accelerometer drift compensation parameter, T_IMUIntegrating time, here the time interval from a time preceding Tp to time Tp, Δ v, is output for acceleration combining_IMUIs at T_IMUThe internal accelerometer combines the velocity increments of the output.

In the step (2), the instruction splitting coefficient c is determined according to the measurement precision of the accelerometer and the precision of the thruster, the obtained formation control instructions are split, the first instruction is combined and measured in real time by the accelerometer in the execution process, the speed increment obtained through actual measurement is compared with a theoretical calculated value after the execution is finished, the actual efficiency of the thruster is obtained, the efficiency of the thruster obtained in the execution process of the second instruction is introduced to recalculate the instruction duration, the total speed increment of the two instructions is equal to the theoretical speed increment, the control precision is improved, the splitting coefficient is smaller when the precision of the thruster is poor or the measurement precision of the combination of the accelerometer is higher, otherwise, the splitting coefficient is larger when the precision of the thruster is good or the measurement precision of the combination of the accelerometer is lower, wherein the formation instruction duration and the splitting method of the speed increment are:

Lt1＝c*Lt；Lt2＝(1-c)*Lt

Δvc1＝c*Δvc；Δvc2＝(1-c)*Δvc

wherein L t1 is a first control command duration, L t2 is a second control command duration, Δ vc1 is a first control theoretical speed increment, and Δ vc2 is a second control theoretical speed increment.

In the step (3), the method for calculating the actual speed increment Δ vr1 and the thruster efficiency coefficient K of the formation satellite in the first control process according to the combined measurement result of the accelerometer specifically comprises the following steps:

Δvr1＝Δv1_IMU-bLt1

K＝Δvr1/Δvc1

wherein, Δ v1_IMUThe measurements are combined for the accelerometer over the L t1 time period.

In the step (4), the specific method for correcting the instruction duration of the formation execution control instruction is as follows:

Lt2c＝Lt1/K-Lt1+Lt2/K

wherein L t2c is the modified queue execution control instruction duration.

Compared with the prior art, the invention has the advantages that:

the invention provides a high-precision formation control method based on an accelerometer combination, which is characterized in that an accelerometer is accessed into a control loop to measure the acceleration of a star body in real time, the calibration coefficient of a thruster is dynamically acquired in the control process by estimating drift compensation parameters, dynamic feedback and correction are realized without the limitation of configuration conditions of an executing mechanism, and the method can be autonomously realized on the star, is autonomously executed after a formation satellite receives a control command, avoids the formation control from being restricted by geometric configuration dimensions, can introduce actual state feedback in the formation control process, corrects the control duration, is more suitable for engineering practice, and has wider application range.

Drawings

FIG. 1 is a schematic flow chart of a formation control method provided by the present invention;

Detailed Description

A high-precision formation control method based on accelerometer combination comprises the steps of adopting an accelerometer combination access control loop to measure star acceleration in real time, determining a set instruction splitting coefficient according to accelerometer combination measurement precision and thruster precision to split formation satellite control instructions, estimating an accelerometer combination drift compensation coefficient before formation control, correcting the command time length after splitting through the accelerometer combination real-time measurement speed increment in the control process, and continuously executing according to the corrected time length to complete formation satellite control, wherein the method comprises the following specific steps of:

(1) the formation satellite calculates a control strategy and a control instruction according to a relative navigation result, wherein the control strategy comprises a speed increment delta vc, a jet duration L t and a jet starting time Tp., and an accelerometer drift compensation parameter b is calculated according to accelerometer measurement data from a period of time before Tp to the time Tp, wherein:

the calculation formula of the accelerometer drift compensation parameter is as follows:

b＝Δv_IMU/T_IMU

wherein b is the combined drift compensation parameter of the accelerometer, T_IMUIntegrating time, here the time interval from a time preceding Tp to time Tp, Δ v, is output for acceleration combining_IMUIs at T_IMUThe speed increment of the combined output of the internal accelerometers;

(2) determining an instruction splitting coefficient c according to the measurement accuracy of the accelerometer and the accuracy of the thruster, splitting an original formation control jet instruction into two instructions, combining and measuring the first formation control instruction by using the accelerometer in real time in the execution process, comparing a speed increment obtained through actual measurement with a theoretical calculated value after the execution is finished to obtain the actual efficiency of the thruster, recalculating the instruction duration by introducing the obtained efficiency of the thruster in the execution process of the second formation control instruction to ensure that the total speed increment of the two instructions is equal to the theoretical speed increment, improving the control accuracy, and when the accuracy of the thruster is poor or the measurement accuracy of the combination of the accelerometers is high, the splitting coefficient is small, otherwise, when the accuracy of the thruster is good or the measurement accuracy of the accelerometer is low, the splitting coefficient is large.

The method for splitting the time length of the formation control instruction comprises the following steps:

Lt1＝c*Lt；Lt2＝(1-c)*Lt

Δvc1＝c*Δvc；Δvc2＝(1-c)*Δvc

wherein L t1 is a first control command duration, L t2 is a second control command duration, Δ vc1 is a first control theoretical speed increment, and Δ vc2 is a second control theoretical speed increment;

(3) executing the split first formation control command obtained in the step (2), and autonomously calculating an actual speed increment delta vr1 and a thruster efficiency coefficient K corresponding to the first formation control command according to the measurement result of the accelerometer after the execution is finished, wherein:

the method for calculating the actual speed increment delta vr1 and the efficiency coefficient K of the thruster in the first control process specifically comprises the following steps:

Δvr1＝Δv1_IMU-bLt1

K＝Δvr1/Δvc1

wherein, Δ v1_IMUIs the accelerometer measurements over the L t1 time period;

(4) correcting the air injection time length of the second formation control instruction according to the efficiency coefficient K calculated in the step (3), continuously executing the formation control instruction according to the corrected time length, finishing formation satellite control, introducing state feedback into the actual control effect of the first control instruction, correcting the control effect in time, and ensuring that the actual control quantity is equal to the theoretical control quantity, so that the control precision is improved, wherein:

the specific method for correcting the instruction duration of the formation execution control instruction comprises the following steps:

Lt2c＝Lt1/K-Lt1+Lt2/K

wherein L t2c is the modified queue execution control instruction duration.

The following is further illustrated with reference to specific examples:

in the embodiment, firstly, a command splitting coefficient is set to be 0.8 according to the control precision of a thruster and the measurement precision of an accelerometer, meanwhile, the calculation of the step (1) is carried out when 600S before the air injection time, when a formation satellite receives a formation control command, the Δ vc is 0.01m/S, the corresponding L t is 100S, Tp is 2020, 1, 0 and 30 minutes and 0 seconds, the accelerometer combined speed increment in the time period from 0 time 20 minutes and 0 seconds to 0 time 30 minutes and 0 seconds is acquired to be 0.003m/S, an accelerometer drift compensation parameter b is calculated to be 0.000005m/S2, after the command is split, the first formation control Δ vc1 is 0.008m/S, L t1 is 80S, the second formation control Δ vc is 0.002m/S, L t2 is 20S, after the first control is finished, the accelerometer measurement result is 0.007m/S, the actual formation control Δ vc is calculated to be 0.002m/S, the theoretical acceleration control coefficient when the formation control efficiency of the first formation satellite reaches 0.8 m/S, the final formation control command is corrected to be 2K, the theoretical control command obtaining Δ vc is carried out, the theoretical control efficiency of a theoretical control command after the formation control Δ v 2/S is carried out, the final control command of a theoretical control of a formation satellite is carried out, the formation satellite is.

While the present invention has been described in detail with reference to the preferred embodiments, it should be understood that the above description should not be taken as limiting the invention. Various modifications and alterations to this invention will become apparent to those skilled in the art upon reading the foregoing description. Accordingly, the scope of the invention should be determined from the following claims.