Full-physical simulation test method and system for ultra-low orbit satellite mass moment control technology

Abstract

The invention provides a full-physical simulation test method and system for an ultra-low orbit satellite mass moment control technology. The method comprises the following steps: step M1, simulating an in-orbit mass moment characteristic through a ground gravitational moment; m2, building an ultra-low orbit satellite mass moment control technology full-physical simulation system; and step M3, designing a mass moment control full-physical test method for verifying the ultra-low orbit satellite mass moment control technology. According to the invention, the in-orbit working state of the mass moment control system can be truly simulated, and the attitude control process and index of the mass moment control technology can be effectively verified, so that a powerful basis is provided for the design of the mass moment control system of an ultra-low orbit satellite.

Description

Technical Field

[0001] The present invention relates to the field of spacecraft technology, and in particular to a full-physics simulation test method and system for ultra-low-orbit satellite mass moment control technology. Background Art

[0002] In today's aerospace industry, satellite technology continues to develop and evolve. Conventional orbit satellites have played an important role in many applications, but satellites operating in ultra-low orbits of 200-300km are emerging. Ultra-low orbit satellites have significant advantages such as fast response speed, high imaging resolution, and miniaturized platform payloads, which enable them to be deployed quickly and achieve high-resolution earth imaging tasks at low cost. They have great application potential in natural disaster emergency monitoring systems and are expected to become a valuable solution.

[0003] However, ultra-low-orbit satellites face an extremely critical challenge. Unlike conventional orbit satellites, the atmospheric density of their orbits has increased significantly. In this case, the traditional zero-momentum flywheel control system needs to compensate for the aerodynamic interference torque for a long time. This process will cause the angular momentum to be saturated and then lose the attitude control ability. The emergence of mass moment control technology provides a new idea. It changes the position of the center of mass by moving several mass blocks inside the system, thereby adjusting the force arm of the aerodynamic force on the celestial body, thereby reducing the interference of aerodynamic torque, and even actively utilizing aerodynamic torque. Applying mass moment control technology to the attitude control of ultra-low-orbit satellites can not only minimize the adverse effects of aerodynamic interference torque and thrust eccentric torque, but also actively use aerodynamic torque to unload angular momentum, greatly improving the accuracy and stability of attitude control.

[0004] In view of the important position of ultra-low-orbit satellites in future aerospace applications and the significant benefits that mass moment control technology may bring, it is extremely necessary to conduct in-depth research and verification of ultra-low-orbit satellite mass moment control technology. However, before practical application, the rationality and reliability of the technology must be ensured. Due to the particularity and complexity of the space environment, it is difficult to conduct a large number of tests and verifications directly on orbit, so full-physical simulation tests on the ground have become a key link. Through full-physical simulation tests on the ground, the mass moment control technology solution can be comprehensively and carefully verified, providing a solid basis for the design of the ultra-low-orbit satellite mass moment control system, promoting the further development and improvement of ultra-low-orbit satellite technology, and then promoting the progress and expansion of the entire aerospace field in related applications.

[0005] Through searching patent documents, it was found that the invention patent with publication number CN201810617228.3 disclosed a full physical simulation test system and method for attitude dynamics of liquid-filled spacecraft. The system includes a set of liquid sloshing torque simulation system and introduces a full physical simulation method based on a three-axis air flotation platform. However, the patent only verifies the dynamic characteristics of the satellite and does not involve the mass moment control simulation method. The invention patent with publication number CN201510954766.8 discloses a full physical test device and test method for satellite image navigation and registration, but the patent is limited to the image navigation and registration test of optical remote sensing satellites and does not involve the mass moment control simulation method.

[0006] To sum up, in response to the above-mentioned problems of the existing technology, it has become a key task to study a full physical simulation test method and system for ultra-low orbit satellite mass moment control technology to solve the problem of ground verification of ultra-low orbit satellite mass moment control technology. Summary of the invention

[0007] In view of the defects in the prior art, the purpose of the present invention is to provide a full physical simulation test method and system for ultra-low orbit satellite mass moment control technology.

[0008] A full physical simulation test method for ultra-low-orbit satellite mass moment control technology provided by the present invention comprises the following steps:

[0009] Step M1, simulating on-orbit mass moment control through ground gravity moment control;

[0010] Step M2, simulating the on-orbit mass moment control based on the ground gravity moment of step M1, and building a full physical simulation system for the ultra-low-orbit satellite mass moment control technology;

[0011] Step M3, based on the full physical simulation system of ultra-low orbit satellite mass moment control technology, design a full physical test method for mass moment control to verify the ultra-low orbit satellite mass moment control technology.

[0012] Preferably, step M1 comprises: the ground air-floating platform changes the gravity moment by adjusting the mass center of the assembly, thereby simulating the control process of the mass moment control system adjusting the mass center of the entire satellite to change the aerodynamic moment when the ultra-low-orbit satellite is in orbit.

[0013] Preferably, in step M1, a ground simulation method of ultra-low-orbit satellite mass moment control technology is adopted, including:

[0014] When the satellite is in orbit, the control torque of the mass moment control system is expressed as:

[0015] T q =r q ×F q (1)

[0016] Among them, r q F is the vector from the satellite's centroid to the satellite's centroid; q is the resultant aerodynamic force acting on the satellite;

[0017] Under the simulated state of the ground air-floating platform, the control torque of the platform and the mass moment control system combination is expressed as:

[0018] T g =r g ×F g (2)

[0019] Among them, r g F is the vector from the center of the air bearing of the air bearing to the center of mass of the combined body; g is the resultant force of gravity acting on the assembly.

[0020] Preferably, in step M2, the full physical simulation system of the ultra-low orbit satellite mass moment control technology includes a mass moment control system, a three-axis air floating table and accessories. The accessories include: a flywheel group on the table (one flywheel in each of the three directions of Xt, Yt and Zt), a photoelectric autocollimator, a laser gyroscope, a table computer and three sets of table support jacks. The flywheel group on the table and the mass moment control system are installed on the three-axis air floating table, and cooperate with the photoelectric autocollimator, the laser gyroscope and the table computer to form a closed-loop control system, thereby completing the construction of the full physical simulation system.

[0021] Preferably, in step M2, a computer on the table is used as a controller, a photoelectric autocollimator and a laser gyroscope are used as sensors, and a mass moment control system and a flywheel assembly on the table are used as actuators to form a feedback control system to control the posture of the table of the three-axis air floating table.

[0022] Preferably, step M3 includes: using the flywheel group on the stage to implement three-axis posture control on the stage body of the three-axis air bearing stage, and when the posture is stable, the flywheels in the Xt and Yt directions exit the closed-loop control, while the flywheel speed is maintained. Then, the mass moment control system is connected to the closed loop, taking over the posture control in the Xt and Yt directions, while the posture control in the Zt direction is still completed by the flywheel in the Zt direction of the stage through closed-loop feedback control.

[0023] Preferably, the ultra-low orbit mass moment control ground full physical test method in step M3 includes: after the three-axis air-bearing platform is balanced, three sets of platform support jacks are lowered, and the flywheel group on the platform is used as an actuator to perform three-axis attitude control.

[0024] Preferably, in step M3, the flywheel control adopts a classic PID control algorithm.

[0025] Preferably, step M3 further comprises: verifying the attitude control index of the mass moment control system by comparing and analyzing the change of the attitude control accuracy of the air bearing platform before and after the mass moment control system is connected.

[0026] The present invention also provides a full physical simulation test system for ultra-low-orbit satellite mass moment control technology, comprising:

[0027] Module S1, simulating on-orbit mass moment control through ground gravity moment control;

[0028] Module S2, based on the ground gravity moment simulation of module S1, builds a full physical simulation system for ultra-low-orbit satellite mass moment control technology;

[0029] Module S3, based on the full physical simulation system of ultra-low orbit satellite mass moment control technology, designs a full physical test method for mass moment control to verify the ultra-low orbit satellite mass moment control technology.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] 1. The present invention can be applied in the development process of my country's ultra-low-orbit satellites, helping to advance satellite research and development work.

[0032] 2. The present invention has the ability to truly simulate the mass moment control process of ultra-low orbit satellites on the ground, thereby providing key basis and support for the control system design of ultra-low orbit satellites.

[0033] 3. The present invention can be used to verify the technical solution of mass moment control of ultra-low orbit satellites and assess the technical indicators of mass moment control, which is of great significance to improving the detection performance of ultra-low orbit satellites. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Other features, objects and advantages of the present invention will become more apparent from the detailed description of non-limiting embodiments made with reference to the following drawings:

[0035] Figure 1 Schematic diagram of the forces acting on an ultra-low-orbit satellite during its in-orbit flight in an embodiment of the present invention;

[0036] Figure 2 Schematic diagram of the composition of the ground full-physics simulation system of the mass moment control technology in the embodiment of the present invention;

[0037] Figure 3 It is a schematic diagram of the ground full-physics simulation system and coordinate system definition of the mass moment control technology in an embodiment of the present invention. DETAILED DESCRIPTION

[0038] The present invention is described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but are not intended to limit the present invention in any form. It should be noted that, for those of ordinary skill in the art, several changes and improvements can also be made without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0039] The present invention utilizes gravity torque on a three-axis air-floating platform to simulate the aerodynamic torque in an actual on-orbit state, thereby being able to truly simulate the mass moment control process of an ultra-low-orbit satellite, so as to effectively verify the rationality of the mass moment control scheme of the ultra-low-orbit satellite and the feasibility of the indicators.

[0040] Embodiment 1:

[0041] This embodiment provides a full physical simulation test method for ultra-low-orbit satellite mass moment control technology, including the following steps:

[0042] Step M1, simulating on-orbit mass moment control through ground gravity moment control.

[0043] Specifically, step M1 includes: the ground air-floating platform changes the gravity moment by adjusting the mass center of the assembly, thereby simulating the control process of the mass moment control system adjusting the mass center of the entire satellite to change the aerodynamic moment when the ultra-low orbit satellite is in orbit.

[0044] Figure 1 It is a schematic diagram of the forces acting on an ultra-low-orbit satellite during its in-orbit flight in an embodiment of the present invention.

[0045] like Figure 1 As shown, in this embodiment, a ground simulation method of ultra-low orbit satellite mass moment control technology is adopted, including:

[0046] When the satellite is in orbit, the control torque of the mass moment control system is expressed as:

[0047] T q =r q ×F q (1)

[0048] Among them, r q F is the vector from the satellite's centroid to the satellite's centroid; q It is the resultant aerodynamic force acting on the satellite.

[0049] Under the simulated state of the ground air-floating platform, the control torque of the platform and the mass moment control system combination is expressed as:

[0050] T g =r g ×F g (2)

[0051] Among them, r gF is the vector from the center of the air bearing of the air bearing to the center of mass of the combined body; g is the resultant force of gravity acting on the assembly.

[0052] From the above, we can see that in the on-orbit state, the mass moment control system changes the aerodynamic moment by adjusting the center of mass of the entire satellite. In the simulation state of the ground air floating platform, the gravity moment is changed by adjusting the center of mass of the assembly. The two have approximate expressions.

[0053] Step M2, based on the ground gravity moment simulation of step M1, the on-orbit mass moment control is carried out to build a full physical simulation system for the ultra-low-orbit satellite mass moment control technology.

[0054] Figure 2 It is a schematic diagram of the composition of the ground full-physics simulation system of the mass moment control technology in an embodiment of the present invention.

[0055] like Figure 2 As shown in the figure, the full physical simulation system of the ultra-low-orbit satellite mass moment control technology includes a mass moment control system, a three-axis air floating table and accessories. The accessories include: a flywheel group on the table (one flywheel in each of the three directions of Xt, Yt and Zt), a computer on the table, an optoelectronic autocollimator, a laser gyroscope and three sets of table support jacks. The flywheel group on the table and the mass moment control system are installed on the three-axis air floating table, and a closed-loop control system is formed in conjunction with the optoelectronic autocollimator, the laser gyroscope and the computer on the table to complete the construction of the full physical simulation system.

[0056] In this embodiment, a computer on the table is used as a controller, a photoelectric autocollimator and a laser gyroscope are used as sensors, a mass moment control system and a flywheel assembly on the table are used as actuators, and a feedback control system is formed to control the posture of the table body of the three-axis air floating table.

[0057] Step M3, based on the full physical simulation system of ultra-low orbit satellite mass moment control technology, design a full physical test method for mass moment control to verify the ultra-low orbit satellite mass moment control technology. Finally, by comparing and analyzing the changes in the attitude control accuracy of the air floating platform before and after the mass moment control system is connected, the attitude control indicators of the mass moment control system are verified.

[0058] Specifically, step M3 includes: using the flywheel group on the stage to implement three-axis posture control on the stage body of the three-axis air bearing stage. When the posture is stable, the flywheels in the Xt and Yt directions exit the closed-loop control, and the flywheel speed is maintained. b , Y b The direction control mechanism is connected to the closed loop and takes over the attitude control in the Xt and Yt directions, while the attitude control in the Zt direction is still completed by the Zt direction flywheel through closed-loop feedback control.

[0059] In this embodiment, the ground full-physical test method for ultra-low orbit mass moment control includes: after the three-axis air-floating platform is balanced, three sets of platform support jacks are lowered, and the flywheel group on the platform is used as an actuator to perform three-axis attitude control, and the flywheel control adopts the classic PID control algorithm.

[0060] Figure 3 It is a schematic diagram of the ground full-physics simulation system and coordinate system definition of the mass moment control technology in an embodiment of the present invention.

[0061] like Figure 3 As shown in the figure, the three-axis attitude control of the three-axis air-floating platform by the flywheel group on the platform is stable (the pointing accuracy is better than 0.01° (3σ), and the stability is better than 5×10 -4 ° / s(3σ)), X t , Y t The flywheel in the direction of the mass moment control system exits the closed-loop control and maintains the flywheel speed. b , Y b Direction control mechanism is connected to the closed loop and takes over X t , Y t Direction attitude control, and Z t The direction attitude control is still completed by the closed-loop feedback control of the flywheel on the platform.

[0062] Finally, record and analyze the three-axis air bearing table X t , Y t The attitude angle and angular velocity data of the direction are used to verify the rationality of the mass moment control system scheme and the feasibility of indicators.

[0063] Embodiment 2:

[0064] The present invention also provides a full physical simulation test system for ultra-low orbit satellite mass moment control technology. The full physical simulation test system for ultra-low orbit satellite mass moment control technology can be realized by executing the process steps of the full physical simulation test method for ultra-low orbit satellite mass moment control technology. That is, those skilled in the art can understand the full physical simulation test method for ultra-low orbit satellite mass moment control technology as a preferred implementation mode of the full physical simulation test system for ultra-low orbit satellite mass moment control technology.

[0065] The full physical simulation test system of the ultra-low-orbit satellite mass moment control technology includes:

[0066] Module S1, simulating on-orbit mass moment control through ground gravity moment control;

[0067] Module S2, based on the ground gravity moment simulation of module S1, builds a full physical simulation system for ultra-low-orbit satellite mass moment control technology;

[0068] Module S3, based on the full physical simulation system of ultra-low orbit satellite mass moment control technology, designs a full physical test method for mass moment control to verify the ultra-low orbit satellite mass moment control technology.

[0069] Those skilled in the art know that, in addition to realizing the system and its various devices, modules, and units provided by the present invention in a purely computer-readable program code, it is entirely possible to realize the same functions in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers by logically programming the method steps. Therefore, the system and its various devices, modules, and units provided by the present invention can be considered as a hardware component, and the devices, modules, and units included therein for realizing various functions can also be regarded as structures within the hardware component; the devices, modules, and units for realizing various functions can also be regarded as both software modules for realizing the method and structures within the hardware component.

[0070] The above describes the specific embodiments of the present invention. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. In the absence of conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A full physical simulation test method for ultra-low-orbit satellite mass moment control technology, characterized in that: The steps include: Step M1, simulating on-orbit mass moment control through ground gravity moment control; Step M2, simulating the on-orbit mass moment control based on the ground gravity moment of step M1, and building a full-physics simulation system for ultra-low-orbit satellite mass moment control technology; Step M3, based on the ultra-low orbit satellite mass moment control technology full physical simulation system, design a mass moment control full physical test method to verify the ultra-low orbit satellite mass moment control technology.

2. According to claim 1, a full physical simulation test method for ultra-low orbit satellite mass moment control technology is characterized in that: The step M1 includes: the ground air-floating platform changes the gravity moment by adjusting the mass center of the assembly, thereby simulating the control process of the mass moment control system adjusting the mass center of the entire satellite to change the aerodynamic moment when the ultra-low-orbit satellite is in orbit.

3. The full physical simulation test method of ultra-low-orbit satellite mass moment control technology according to claim 2 is characterized in that: In the step M1, a ground simulation method of ultra-low-orbit satellite mass moment control technology is adopted, including: When the satellite is in orbit, the control torque of the mass moment control system is expressed as: T q =r q ×F q (1) Among them, r q F is the vector from the satellite mass center to the satellite centroid; q is the resultant aerodynamic force acting on the satellite; Under the simulated state of the ground air-floating platform, the control torque of the platform and the mass moment control system combination is expressed as: T g =r g ×F g (2) Among them, r g F is the vector from the center of the air bearing of the air bearing to the center of mass of the combined body; g is the resultant force of gravity acting on the assembly.

4. The full physical simulation test method of ultra-low-orbit satellite mass moment control technology according to claim 1 is characterized in that: In the step M2, the ultra-low orbit satellite mass moment control technology full physical simulation system includes a mass moment control system, a three-axis air floating platform and accessories, the accessories include: an on-stage flywheel group, an optoelectronic autocollimator, a laser gyroscope, an on-stage computer and 3 groups of platform support jacks, the on-stage flywheel group includes a flywheel in each of the three directions of Xt, Yt and Zt, the on-stage flywheel group and the mass moment control system are installed on the three-axis air floating platform, and cooperate with the optoelectronic autocollimator, the laser gyroscope and the on-stage computer to form a closed-loop control system, thereby completing the construction of the full physical simulation system.

5. The full physical simulation test method of ultra-low-orbit satellite mass moment control technology according to claim 4 is characterized in that: In step M2, the on-stage computer is used as a controller, the photoelectric autocollimator and the laser gyroscope are used as sensors, the mass moment control system and the on-stage flywheel group are used as actuators to form a feedback control system to control the posture of the stage of the three-axis air floating stage.

6. The full physical simulation test method of ultra-low-orbit satellite mass moment control technology according to claim 4 is characterized in that: The step M3 includes: using the flywheel group on the stage to implement three-axis posture control on the stage body of the three-axis air bearing stage. When the posture is stable, the flywheels in the Xt and Yt directions exit the closed-loop control, and the flywheel speed is maintained. Then, the mass moment control system is connected to the closed loop and takes over the posture control in the Xt and Yt directions, while the posture control in the Zt direction is still completed by the flywheel in the Zt direction through closed-loop feedback control.

7. The full physical simulation test method for ultra-low-orbit satellite mass moment control technology according to claim 6 is characterized in that: The ground full-physical test method for ultra-low orbit mass moment control in step M3 includes: after the three-axis air-floating platform is balanced, the three sets of platform support jacks are lowered, and the flywheel group on the platform is used as an actuator to perform three-axis attitude control.

8. The full physical simulation test method of ultra-low-orbit satellite mass moment control technology according to claim 7 is characterized in that: In step M3, the flywheel control adopts the classic PID control algorithm.

9. The full physical simulation test method of ultra-low-orbit satellite mass moment control technology according to claim 8 is characterized in that: The step M3 also includes: verifying the attitude control index of the mass moment control system by comparing and analyzing the change of the attitude control accuracy of the air bearing platform before and after the mass moment control system is connected.

10. A full physical simulation test system for ultra-low-orbit satellite mass moment control technology, characterized in that: include: Module S1, simulating on-orbit mass moment control through ground gravity moment control; Module S2, based on the ground gravity moment simulation of module S1, on-orbit mass moment control is constructed to build a full physical simulation system for ultra-low-orbit satellite mass moment control technology; Module S3, based on the ultra-low orbit satellite mass moment control technology full physical simulation system, designs a mass moment control full physical test method to verify the ultra-low orbit satellite mass moment control technology.

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