Spacecraft maneuver detection method

Abstract

The invention relates to a spacecraft maneuver detection method, and belongs to the field of spaceflight measurement and control. According to the method, the mechanical energy change and tangential acceleration of the spacecraft are calculated by adopting an energy method, whether the spacecraft has maneuvering is analyzed by calculating the mechanical energy change of the spacecraft, the non-conservative force and the maneuvering acceleration are calculated according to the relation between the orbit mechanical energy and the non-conservative force, whether maneuvering exists is judged, and the maneuvering time and the magnitude of the maneuvering force are determined. Therefore, according to the method, the maneuvering time and the magnitude of the maneuvering force can be solved at a time, the speed is high, and the accuracy is high; in addition, the method does not need to add extra observed quantity, and the requirement for coverage of track data is not high, so that the method is convenient to operate, high in applicability and low in cost.

Description

Technical Field

[0001] The present invention relates to a method for detecting spacecraft maneuvering, which calculates orbital mechanical energy according to spacecraft orbital data, judges the occurrence of maneuvering according to energy changes, and determines maneuvering time, maneuvering acceleration and maneuvering force, and belongs to the field of aerospace measurement and control. Background Art

[0002] Maneuver detection is very important for orbit determination and prediction of non-cooperative space targets. Currently, orbit determination method is often used for analysis. However, since the maneuvering time and maneuvering force of non-cooperative targets are unknown, and orbit determination method is difficult to solve the maneuvering time and maneuvering force at the same time, the efficiency of maneuvering detection is very low. Therefore, maneuvering detection is still one of the difficulties in orbit research of non-cooperative targets. Summary of the invention

[0003] In response to the problem of orbital maneuver detection of non-cooperative targets, the present invention proposes a spacecraft maneuver detection method based on orbital energy analysis, which can calculate the maneuver time and maneuver force at one time with high speed and accuracy. In addition, the method of the present invention does not require additional observations and does not have high requirements for orbital data coverage.

[0004] The technical solution adopted by the present invention to solve the technical problem is as follows:

[0005] A method for detecting spacecraft maneuvers comprises the following steps:

[0006] (1) Calculate orbital mechanical energy using orbital data;

[0007] If the spacecraft orbit data is orbital element data, the orbital elements are converted into positions and orbital velocities, the normalized kinetic energy of the spacecraft is calculated using the orbital velocity, the gravitational potential energy of the spacecraft is calculated using the spacecraft position and the Earth's gravity field model, and the gravitational potential energy of the Sun and the Moon is calculated using the relationship between the Sun-Earth position and the Earth-Moon position;

[0008] The calculation formula of spacecraft orbital mechanical energy is as follows

[0009] E=0.5v 2 +V Earth +V Moon +V Sun (1)

[0010] Where E is the spacecraft orbital mechanical energy, V Earth is the gravitational potential energy of the spacecraft, m is the mass of the spacecraft, v is the velocity of the spacecraft, V Moon 、V Sun is the potential energy of the moon and sun’s gravity;

[0011] (2) Use orbital mechanical energy to calculate the tangential acceleration of the spacecraft caused by non-conservative forces;

[0012] a n =dE / ds (2)

[0013] In the formula, a n is the tangential acceleration caused by the non-conservative force of the spacecraft, E is the orbital mechanical energy of the spacecraft, and s is the flight distance;

[0014] (3) Calculate the theoretical atmospheric drag acceleration of the spacecraft using the standard atmospheric model or atmospheric density observations, and calculate the theoretical tangential acceleration caused by solar light pressure using the light pressure model;

[0015] The theoretical atmospheric drag acceleration a of the spacecraft is calculated using the following formula (3): d :

[0016]

[0017] Among them, C D is the atmospheric drag coefficient, ρ is the orbital atmospheric density calculated or observed using the standard atmospheric model, A is the spacecraft headwind cross-sectional area, v is the spacecraft speed, and v a is the velocity of the local atmosphere;

[0018] Calculate the tangential acceleration a caused by solar pressure based on the position of the sun and the area and position parameters of the spacecraft s .

[0019] (4) Calculate the acceleration of the spacecraft tangential maneuver based on the non-conservative force acceleration, the theoretical atmospheric drag acceleration, and the theoretical solar pressure acceleration:

[0020] a m =a n -a d -a s (4)

[0021] In the formula, a s is the solar pressure acceleration;

[0022] (5) Calculate the maximum error of the tangential maneuver acceleration and determine whether the maneuver occurs;

[0023] The tangential acceleration a caused by the non-conservative force of the spacecraft is selected n The time series of a is calculated n The root mean square error of n The maximum error is a d +a s The theoretical value or 4 times the root mean square error of the theoretical value is taken as a d +a s The maximum error is a n with a d +as The sum of the maximum errors is taken as the tangential maneuver acceleration a m The maximum error of

[0024] If there is a tangential maneuvering acceleration a m Greater than a m In the case of the maximum error, it is judged that a short-term maneuver occurs, and the tangential maneuver acceleration a m Greater than a m The time corresponding to the maximum error is the maneuvering time;

[0025] If there is no tangential maneuver acceleration a m Greater than a m In the case of the maximum error, analyze the change of orbital mechanical energy E. If E continues to increase, that is, the average energy change rate dE / dt of the selected data sequence is greater than 0, it is judged that a continuous maneuver occurs. m Smoothing is performed, that is, selecting a suitable time window to perform sliding average on the tangential maneuvering acceleration; through the tangential maneuvering acceleration a m The sum of the atmospheric drag acceleration and the solar pressure acceleration a d +a s The maximum error of the smoothed tangential maneuver acceleration a is compared to determine whether the spacecraft maneuver has occurred. m Both are greater than the sum of the atmospheric drag acceleration and the solar pressure acceleration a d +a s The maximum error, a m Greater than a d +a s The time corresponding to the data with the maximum error is the maneuvering time;

[0026] (6) Calculate the magnitude of the tangential maneuvering force when the maneuver occurs;

[0027] The tangential maneuvering force can be calculated using the following formula (5):

[0028] f=ma m (5)

[0029] Among them, f is the tangential force, a m is the tangential acceleration.

[0030] Beneficial effects of the present invention:

[0031] The present invention adopts an energy method to calculate the mechanical energy change and tangential acceleration of a spacecraft, analyzes whether the spacecraft has maneuvers by calculating the mechanical energy change of the spacecraft, calculates non-conservative forces and maneuvering acceleration by the relationship between orbital mechanical energy and non-conservative forces, judges whether there is maneuvering, and determines the maneuvering time and maneuvering force size, without the need for orbit determination calculation. Therefore, the method of the present invention can solve the maneuvering time and maneuvering force size at one time, with high speed and high accuracy. In addition, the method of the present invention does not need to add additional observation quantities, and does not have high requirements on the coverage of orbital data. Therefore, the method of the present invention is easy to operate, has strong applicability and low cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The present invention is a flow chart of a method for maneuvering detection of a spacecraft. DETAILED DESCRIPTION

[0033] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0034] The flow chart of a method for detecting spacecraft maneuvers provided by the present invention is as follows: Figure 1 shown.

[0035] (1) Calculate orbital mechanical energy using spacecraft orbit data and gravitational potential models;

[0036] First, if the spacecraft orbit data is orbital element data, the orbital elements are converted into positions and orbital velocities, and the normalized kinetic energy of the spacecraft is calculated using the orbital velocity. The gravitational potential energy of the spacecraft is calculated using the spacecraft position and the Earth's gravity field model, and the gravitational potential energy of the Sun and the Moon is calculated using the relationship between the Sun-Earth position and the Earth-Moon position.

[0037] Calculate the spacecraft orbital mechanical energy according to formula (1);

[0038] E=0.5mv 2 +V Earth +V Moon +V Sun (1)

[0039] Where E is the spacecraft orbital mechanical energy, V Earth is the gravitational potential energy of the spacecraft, m is the mass of the spacecraft, v is the velocity of the spacecraft, V Moon 、V Sun is the potential energy of the gravitational forces of the moon and the sun.

[0040] (2) Based on the relationship between orbital mechanical energy and the non-conservative force acting on the spacecraft, the magnitude of the tangential acceleration of the spacecraft caused by the non-conservative force is calculated, which is referred to as the non-conservative force acceleration.

[0041] Use formula (2) to calculate the tangential acceleration of the spacecraft caused by the non-conservative force:

[0042] a n =dE / ds (2)

[0043] In the formula, a n is the tangential acceleration of the spacecraft, E is the orbital mechanical energy of the spacecraft, and s is the flight distance.

[0044] (3) Use the standard atmospheric model or atmospheric density observations to calculate the theoretical atmospheric drag acceleration of the spacecraft, and use the light pressure model to calculate the theoretical tangential acceleration a caused by solar light pressure. s .

[0045] The theoretical atmospheric drag acceleration a of the spacecraft is calculated using the following formula (3): d :

[0046]

[0047] Among them, C D is the atmospheric drag coefficient, ρ is the orbital atmospheric density calculated or observed using the standard atmospheric model, A is the spacecraft headwind cross-sectional area, and v a is the velocity of the local atmosphere and v is the spacecraft velocity.

[0048] Then, the tangential acceleration a caused by the solar pressure is calculated based on the position of the sun and the area and position of the spacecraft. s .

[0049] (4) Calculate the magnitude of the spacecraft tangential maneuver acceleration based on the non-conservative force acceleration, the theoretical atmospheric drag acceleration, and the theoretical solar pressure acceleration. The tangential maneuver acceleration a is obtained by subtracting the tangential acceleration caused by atmospheric drag and solar pressure from the tangential acceleration caused by the non-conservative force. m :

[0050] a m =a n -a d -a s (4)

[0051] In the formula, a s is the tangential acceleration caused by solar pressure;

[0052] (5) Calculate the maximum error of the tangential maneuver acceleration and determine whether the maneuver occurs;

[0053] The tangential acceleration a caused by the non-conservative force of the spacecraft is selected n The time series of a is calculated n The root mean square error of n The maximum error is a d +a s The theoretical value or 4 times the root mean square error of the theoretical value is taken as ad +a s The maximum error is a n with a d +a s The sum of the maximum errors is taken as the tangential maneuver acceleration a m The maximum error of

[0054] If there is a tangential maneuvering acceleration a m Greater than a m In the case of the maximum error, it is judged that a short-term maneuver occurs, and the tangential maneuver acceleration a m Greater than a m The time corresponding to the maximum error is the maneuvering time;

[0055] If there is no tangential maneuver acceleration a m Greater than a m In the case of the maximum error, analyze the change of orbital mechanical energy E. If E continues to increase, that is, the average energy change rate dE / dt of the selected data sequence is greater than 0, it is judged that a continuous maneuver occurs. m Smoothing is performed, that is, selecting a suitable time window to perform sliding average on the tangential maneuvering acceleration; through the tangential maneuvering acceleration a m The sum of the atmospheric drag acceleration and the solar pressure acceleration a d +a s The maximum error of the smoothed tangential maneuver acceleration a is compared to determine whether the spacecraft maneuver has occurred. m Both are greater than the sum of the atmospheric drag acceleration and the solar pressure acceleration a d +a s The maximum error, a m Greater than a d +a s The time corresponding to the data with the maximum error is the maneuvering time;

[0056] (6) Calculate the magnitude of the tangential maneuvering force when the maneuver occurs.

[0057] The tangential maneuvering force can be calculated using the following formula:

[0058] f=ma m (5)

[0059] Among them, f is the tangential force, a m is the tangential acceleration.

Claims

1. A method for detecting spacecraft maneuvers, characterized in that: The following steps are involved: (1) Calculate orbital mechanical energy E using orbital data; (2) Use orbital mechanical energy to calculate the tangential acceleration of the spacecraft caused by non-conservative forces; A n =dE / ds In the formula, a n is the tangential acceleration caused by the non-conservative force of the spacecraft, E is the orbital mechanical energy of the spacecraft, and s is the flight distance; (3) Calculate the theoretical atmospheric drag acceleration a of the spacecraft d and the tangential acceleration a caused by the theoretical solar pressure s ; (4) Calculate the magnitude of the spacecraft tangential maneuver acceleration based on the non-conservative force acceleration, the theoretical atmospheric drag acceleration, and the theoretical tangential acceleration caused by solar pressure: a m =a n -a d -a s In the formula, a m is the spacecraft tangential maneuver acceleration, a s is the tangential acceleration caused by solar pressure; (5) Calculate the maximum error of the tangential maneuver acceleration to determine whether the maneuver occurs; (6) Calculate the magnitude of the tangential maneuver force when the maneuver occurs; The tangential maneuvering force can be calculated using the following formula: f=ma m Among them, f is the tangential force, a m is the tangential acceleration.

2. A method for detecting spacecraft maneuvers according to claim 1, characterized in that: In step (1), if the spacecraft orbit data is orbital element data, the orbital element is converted into position and orbital velocity, the normalized kinetic energy of the spacecraft is calculated using the orbital velocity, the gravitational potential energy of the spacecraft is calculated using the spacecraft position and the Earth's gravity field model, and the gravitational potential energy of the Sun and the Moon is calculated using the relationship between the Sun-Earth position and the Earth-Moon position; The calculation formula of spacecraft orbital mechanical energy is as follows E=0.5v 2 +V Earth +V Moon +V Sun (1) Where E is the spacecraft orbital mechanical energy, V Earth is the gravitational potential energy of the spacecraft, m is the mass of the spacecraft, v is the velocity of the spacecraft, V Moon 、V Sun is the potential energy of the gravitational forces of the moon and the sun.

3. A method for detecting spacecraft maneuvers according to claim 2, characterized in that: In step (3), the tangential acceleration a caused by the solar pressure is calculated based on the position of the sun and the area and position parameters of the spacecraft. s .

4. A method for detecting spacecraft maneuvers according to claim 2, characterized in that: In step (3), the theoretical atmospheric drag acceleration a of the spacecraft is calculated using the standard atmospheric model or atmospheric density. d .

5. A method for detecting spacecraft maneuvers according to claim 3, characterized in that: Atmospheric density is the orbital atmospheric density calculated using standard atmospheric models or observed.

6. A method for detecting spacecraft maneuvers according to claim 4, characterized in that: Step (5) specifically includes: If there is a tangential maneuvering acceleration a m Greater than a m In the case of the maximum error, it is judged that a short-term maneuver occurs, and the tangential maneuver acceleration a m Greater than a m The time corresponding to the maximum error is the maneuvering time; If there is no tangential maneuver acceleration a m Greater than a m In the case of the maximum error, analyze the change of orbital mechanical energy E. If E continues to increase, that is, the average energy change rate dE / dt of the selected data sequence is greater than 0, it is judged that a continuous maneuver occurs. m Smoothing is performed, that is, selecting a suitable time window to perform sliding average on the tangential maneuvering acceleration; through the tangential maneuvering acceleration a m The sum of the atmospheric drag acceleration and the solar pressure acceleration a d +a s The maximum error of the smoothed tangential maneuver acceleration a is compared to determine whether the spacecraft maneuver has occurred. m Both are greater than the sum of the atmospheric drag acceleration and the solar pressure acceleration a d +a s The maximum error, a m Greater than a d +a s The time corresponding to the data with the maximum error is the maneuvering time.

7. A method for detecting spacecraft maneuvers according to claim 6, characterized in that: In step (5), the tangential acceleration a caused by the non-conservative force of the spacecraft is selected n The time series of a is calculated n The root mean square error of n The maximum error is a d +a s The theoretical value or 4 times the root mean square error of the theoretical value is taken as a d +a s The maximum error is a n with a d +a s The maximum error sum is the tangential acceleration a caused by the non-conservative force of the spacecraft m The maximum error.

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