A continuously variable rotational inertia damper for stabilizing an on-orbit target
By using a continuously variable moment of inertia damping device to stabilize the on-orbit target, the rotational inertia parameters of the target spacecraft are adjusted, solving the vibration problem caused by circumferential periodic disturbance torque, and achieving stable capture of the spacecraft and protection of its internal equipment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- BEIJING UNIV OF POSTS & TELECOMM
- Filing Date
- 2025-01-02
- Publication Date
- 2026-07-03
AI Technical Summary
Existing technologies have failed to effectively suppress vibrations of target spacecraft during capture missions, especially vibrations caused by circumferential periodic disturbance torques, which affect the pointing accuracy of spacecraft and the performance of internal instruments, and lack adaptive vibration reduction methods.
A stepless variable moment of inertia vibration reduction device is adopted to stabilize the on-orbit target. By adjusting the rotational inertia parameters of the target spacecraft through the variable moment of inertia component and the torsion spring component, vibration suppression and energy transfer are achieved, and the device can adapt to circumferential disturbance torques of different frequencies.
It achieves vibration suppression and energy transfer of target spacecraft over a wide frequency band, ensuring stable capture of spacecraft, avoiding the impact of vibration on pointing accuracy and internal instruments, and possesses adaptive adjustment capabilities.
Smart Images
Figure CN122328503A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of space robot research and engineering, specifically to a continuously variable moment of inertia damping device for stabilizing on-orbit targets. Background Technology
[0002] When servicing spacecraft perform on-orbit life extension missions, the capture operation plays a crucial role. In practice, the target spacecraft itself is always subjected to periodic excitations from loads such as control moment gyroscopes, reaction wheels, and thrusters. Furthermore, due to issues such as velocity mismatch at the capture point or the target spacecraft's spin motion, capture is accompanied by strong contact collisions, which in turn excite vibrations in the flexible components of the target spacecraft, primarily solar panels. This results in the target spacecraft experiencing undesirable periodic disturbance torques in the circumferential direction, which can impair its pointing accuracy and affect the performance of its internal precision instruments. However, current research typically focuses only on suppressing disturbances from external excitations to the servicing spacecraft and its base, without investigating vibration reduction methods for the target spacecraft as the dominant vibration system. Moreover, during capture missions, the frequency of the periodic disturbance torques experienced by the target spacecraft will vary due to uncertainties such as the inherent properties of different target spacecraft and the uncontrollable circumferential relative velocity. Therefore, in order to ensure the safety of the target spacecraft and suppress the negative impact of circumferential periodic disturbance torque on the operation of the target spacecraft, a stepless variable moment of inertia vibration reduction device for stabilizing on-orbit targets is proposed. Under different operating conditions, it can steplessly adjust the moment of inertia parameters of internal components to stabilize on-orbit target spacecraft within a wide range of circumferential disturbance torque frequencies, thereby achieving stable capture. Summary of the Invention
[0003] This invention addresses the challenge of a target spacecraft subjected to external circumferential periodic disturbance torque after capture. To solve the problem of vibration suppression and energy transfer by the target spacecraft itself, a stepless variable moment of inertia vibration reduction device for stabilizing on-orbit targets is proposed.
[0004] To achieve the above objectives, the present invention adopts the following technical solution:
[0005] A stepless variable moment of inertia vibration reduction device for stabilizing on-orbit targets mainly includes a structural frame assembly, a variable moment of inertia assembly, a torsion spring assembly, and an electrical assembly.
[0006] The structural frame assembly mainly consists of a capture mechanism connector (301), an end cap (302), bearing one (303), a space target rotating shaft (304), bearing two (305), bearing three (306), bearing four (308), a device housing (310), a base connector (311), and a bushing (316). The variable moment of inertia assembly includes a variable moment of inertia mechanism one (201), a variable moment of inertia mechanism two (202), a mechanism support one (307), a mechanism support two (314), a mechanism rotating shaft (313), a torsion spring support one (309), and a torsion spring support two (315). The torsion spring assembly includes a torsion spring two (317) and a torsion spring one (312). The electrical components include an acceleration sensor (318) and a controller (203).
[0007] Furthermore, the end cap (302), device housing (310), bushing (316), and base connector (311) are fixedly connected as a whole. The outer rings of bearing one (303) and bearing two (305) are connected to the device housing (310), and the inner rings are connected to the space target rotating shaft (304), thus the space target rotating shaft (304) and the device housing (310) form a rotating pair connection, with the rotation axis being the a-axis. The capture mechanism connector (301) is fixedly connected to the space target rotating shaft (304). The outer rings of bearing three (306) and bearing four (308) are connected to the device housing (310), and the inner rings are connected to the mechanism rotating shaft (313), thus the mechanism rotating shaft (313) and the device housing (310) form a rotating pair connection, with the rotation axis being the a-axis. The torsion spring bracket one (309), torsion spring bracket two (315), mechanism bracket one (307), and mechanism bracket two (314) are all fixedly connected to the mechanism shaft (313). The variable moment of inertia mechanism one (201) is connected to mechanism bracket one (307), and the variable moment of inertia mechanism two (202) is connected to mechanism bracket two (314). The two ends of the torsion spring one (312) are respectively connected to the base connector (311) and the torsion spring bracket one (309), and can generate torsion around axis a. The two ends of the torsion spring two (317) are respectively connected to the capture mechanism connector (301) and the torsion spring bracket two (315), and can generate torsion around axis a. The controller (203) and the acceleration sensor (318) are respectively connected to the device housing (310) and the space target shaft (304).
[0008] Furthermore, the variable moment of inertia mechanism one (201) and variable moment of inertia mechanism two (202) have the same mechanical structure, which mainly includes bracket one (401), bracket two (402), lead screw (403), slide rail one (404), coupling (405), motor (406), driver (407), bracket three (408), position sensor (409), mass block (410), slide rail two (411), and base plate (412). Among them, bracket one (401), bracket two (402), bracket three (408), slide rail one (404), and slide rail two (411) are all connected to the base plate (412); motor (406), driver (407), and position sensor (409) are all connected to bracket three (408). The motor (406) drives the lead screw (403) to rotate through the coupling (405), thereby causing the mass block (410) to slide up and down along the slide rail one (404) and the slide rail two (411).
[0009] Furthermore, the continuously variable moment of inertia damping device (102) for stabilizing the on-orbit target is connected to the spacecraft base (101) or the capture mechanism (103) through the base connector (311) or the capture mechanism connector (301), respectively. The target spacecraft (104), the spacecraft base (101) and the capture mechanism (103) are external systems of the present invention.
[0010] Furthermore, taking the variable moment of inertia mechanism one (201) as an example, it is fixedly connected to the mechanism shaft (313) through the mechanism support one (307), so it can rotate around the a-axis. The moment of inertia of the variable moment of inertia mechanism one (201) around the a-axis can be steplessly adjusted by adjusting the size of the rotation radius h1 of the mass block (410) around the a-axis. The same applies to the variable moment of inertia mechanism two (202). In addition, the installation positions of the variable moment of inertia mechanism one (201) and the variable moment of inertia mechanism two (202) are symmetrical along the a-axis, and the rotation radii h1 and h2 of the mass block (410) around the a-axis in both are always kept equal to ensure that the center of mass of the stepless variable moment of inertia damping device (102) for stabilizing the target on the track coincides with the a-axis, and avoids additional inertial force due to eccentricity.
[0011] Furthermore, the moments of inertia of torsion spring 1 (312), torsion spring 2 (317), bearing 1 (303), bearing 2 (305), bearing 3 (306), bearing 4 (308), and accelerometer (318) are ignored. After capture, the target spacecraft (104), capture mechanism (103), capture mechanism connector (301), and space target rotation axis (304) are considered as a whole, and the moment of inertia about axis a is set as J. t Treating the variable moment of inertia component as a whole, its moment of inertia about axis a is denoted as J. dThe radii of rotation of the two mass blocks (410) in the variable moment of inertia assembly are variable, therefore their moments of inertia are variable, denoted as J. v The moment of inertia of the remaining fixed parts is set as J. c The three satisfy the following relationship: J d =J c +J v The spacecraft base (101), end cap (302), device shell (310), bushing (316), and base connector (311) are considered as a whole, and their moment of inertia about axis a is denoted as J. b Set the stiffness of torsion spring 2 (317) to k2, and the stiffness of torsion spring 1 (312) to k1. Target spacecraft (104) / J t The vibration angular displacement is θ2, and the variable moment of inertia mechanism is / J d The vibration angular displacement is θ1.
[0012] Furthermore, assume that the circumferential harmonic disturbance torque around the a-axis experienced by the target spacecraft (104) is M = Asinωt.
[0013] Furthermore, the present invention adjusts the moment of inertia J of the variable moment of inertia component about the rotation axis. d (Essentially, it is about adjusting the moment of inertia J of the mass block (410) about the rotation axis) v ), making The frequency ω of the external disturbance torque is equal to that of the external disturbance torque, which can suppress the vibration of the target spacecraft (104) and transfer the vibration energy of the external disturbance torque input to the variable moment of inertia component. If the frequency ω of the external disturbance torque changes, the moment of inertia J of the variable moment of inertia component about axis a can be continuously adjusted. d Achieve broadband adaptive vibration suppression.
[0014] The technical solution provided by this invention has the following characteristics compared with the prior art:
[0015] After the target is captured in orbit, traditional vibration suppression methods typically focus only on the disturbances caused by external excitations to the servicing spacecraft and its base, rarely considering reducing the vibration of the target spacecraft as a primary objective. Therefore, this invention addresses the scenario where the target spacecraft is subjected to periodic circumferential disturbance torques. By introducing a two-degree-of-freedom undamped vibration model and a variable moment of inertia mechanism, it achieves vibration suppression and energy transfer of the target spacecraft under circumferential harmonic disturbances after capture. Furthermore, when the external excitation frequency changes, by adjusting the moment of inertia of the variable moment of inertia mechanism relative to the center of rotation, stepless adjustment of system parameters and adaptive vibration suppression of the target spacecraft to changes in external disturbances can be achieved. Attached Figure Description
[0016] Figure 1This is a schematic diagram of the overall three-dimensional structure of a specific embodiment of the present invention;
[0017] Figure 2 A three-dimensional structural schematic diagram of the continuously variable moment of inertia vibration reduction device for stabilizing on-orbit targets according to the present invention;
[0018] Figure 3 This is a longitudinal cross-sectional view of the continuously variable moment of inertia vibration reduction device for stabilizing on-orbit targets according to the present invention.
[0019] Figure 4 This is a three-dimensional structural schematic diagram of the variable moment of inertia mechanism of the present invention;
[0020] Figure 5 This is an equivalent mechanical principle diagram of a specific embodiment of the present invention.
[0021] The labels in the attached diagram are explained as follows:
[0022] Spacecraft base (101), continuously variable moment of inertia damping device for stabilizing on-orbit targets (102), capture mechanism (103), target spacecraft (104), variable moment of inertia mechanism one (201), variable moment of inertia mechanism two (202), controller (203), capture mechanism connector (301), end cap (302), bearing one (303), space target rotating shaft (304), bearing two (305), bearing three (306), mechanism support one (307), bearing four (308), torsion spring support one (309), device shell (310) , base connector (311), torsion spring one (312), mechanism rotating shaft (313), mechanism bracket two (314), torsion spring bracket two (315), bushing (316), torsion spring two (317), acceleration sensor (318), bracket one (401), bracket two (402), lead screw (403), slide rail one (404), coupling (405), motor (406), driver (407), bracket three (408), position sensor (409), mass block (410), slide rail two (411), base plate (412). Detailed Implementation Plan
[0023] The following is in conjunction with the appendix Figures 1-5 The present invention will be further described as follows:
[0024] A stepless variable moment of inertia vibration reduction device for stabilizing on-orbit targets mainly includes a structural frame assembly, a variable moment of inertia assembly, a torsion spring assembly, and an electrical assembly.
[0025] The structural frame assembly mainly consists of a capture mechanism connector (301), an end cap (302), bearing one (303), a space target rotating shaft (304), bearing two (305), bearing three (306), bearing four (308), a device housing (310), a base connector (311), and a bushing (316). The variable moment of inertia assembly includes a variable moment of inertia mechanism one (201), a variable moment of inertia mechanism two (202), a mechanism support one (307), a mechanism support two (314), a mechanism rotating shaft (313), a torsion spring support one (309), and a torsion spring support two (315). The torsion spring assembly includes a torsion spring two (317) and a torsion spring one (312). The electrical components include an acceleration sensor (318) and a controller (203).
[0026] Furthermore, the end cap (302), device housing (310), bushing (316), and base connector (311) are fixedly connected as a whole. The outer rings of bearing one (303) and bearing two (305) are connected to the device housing (310), and the inner rings are connected to the space target rotating shaft (304), thus the space target rotating shaft (304) and the device housing (310) form a rotating pair connection, with the rotation axis being the a-axis. The capture mechanism connector (301) is fixedly connected to the space target rotating shaft (304). The outer rings of bearing three (306) and bearing four (308) are connected to the device housing (310), and the inner rings are connected to the mechanism rotating shaft (313), thus the mechanism rotating shaft (313) and the device housing (310) form a rotating pair connection, with the rotation axis being the a-axis. The torsion spring bracket one (309), torsion spring bracket two (315), mechanism bracket one (307), and mechanism bracket one (307) are all fixedly connected to the mechanism shaft (313). The variable moment of inertia mechanism one (201) is connected to mechanism bracket one (307), and the variable moment of inertia mechanism two (202) is connected to mechanism bracket two (314). The two ends of the torsion spring one (312) are respectively connected to the base connector (311) and the torsion spring bracket one (309), and can generate torsion around axis a. The two ends of the torsion spring two (317) are respectively connected to the capture mechanism connector (301) and the torsion spring bracket two (315), and can generate torsion around axis a. The controller (203) and the acceleration sensor (318) are respectively connected to the device housing (310) and the space target shaft (304).
[0027] Furthermore, the variable moment of inertia mechanism one (201) and variable moment of inertia mechanism two (202) have the same mechanical structure, which mainly includes bracket one (401), bracket two (402), lead screw (403), slide rail one (404), coupling (405), motor (406), driver (407), bracket three (408), position sensor (409), mass block (410), slide rail two (411), and base plate (412). Among them, bracket one (401), bracket two (402), bracket three (408), slide rail one (404), and slide rail two (411) are all connected to the base plate (412); motor (406), driver (407), and position sensor (409) are all connected to bracket three (408). The motor (406) drives the lead screw (403) to rotate through the coupling (405), thereby causing the mass block (410) to slide up and down along the slide rail one (404) and the slide rail two (411).
[0028] Furthermore, the continuously variable moment of inertia damping device (102) for stabilizing the on-orbit target is connected to the spacecraft base (101) or the capture mechanism (103) through the base connector (311) or the capture mechanism connector (301), respectively. The target spacecraft (104), the spacecraft base (101) and the capture mechanism (103) are external systems of the present invention.
[0029] Furthermore, taking the variable moment of inertia mechanism one (201) as an example, it is fixedly connected to the mechanism shaft (313) through the mechanism support one (307), so it can rotate around the a-axis. The moment of inertia of the variable moment of inertia mechanism one (201) around the a-axis can be steplessly adjusted by adjusting the size of the rotation radius h1 of the mass block (410) around the a-axis. The same applies to the variable moment of inertia mechanism two (202). In addition, the installation positions of the variable moment of inertia mechanism one (201) and the variable moment of inertia mechanism two (202) are symmetrical along the a-axis, and the rotation radii h1 and h2 of the mass block (401) around the a-axis in both are always kept equal to ensure that the center of mass of the stepless variable moment of inertia damping device (102) for stabilizing the target on the track coincides with the a-axis, and avoids additional inertial force due to eccentricity.
[0030] Furthermore, the moments of inertia of torsion spring 1 (312), torsion spring 2 (317), bearing 1 (303), bearing 2 (305), bearing 3 (306), bearing 4 (308), and accelerometer (318) are ignored. After capture, the target spacecraft (104), capture mechanism (103), capture mechanism connector (301), and space target rotation axis (304) are considered as a whole, and the moment of inertia about axis a is set as J. t Treating the variable moment of inertia component as a whole, its moment of inertia about axis a is denoted as J. dThe radii of rotation of the two mass blocks (410) are variable, therefore their moments of inertia are also variable, denoted as J. v The moment of inertia of the remaining fixed parts is set as J. c The three satisfy the following relationship: J d =J c +J v The spacecraft base (101), end cap (302), device shell (310), bushing (316), and base connector (311) are considered as a whole, and their moment of inertia about axis a is denoted as J. b Set the stiffness of torsion spring 2 (317) to k2, and the stiffness of torsion spring 1 (312) to k1. Target spacecraft (104) / J t The vibration angular displacement is θ2, and the variable moment of inertia mechanism is / J d The vibration angular displacement is θ1.
[0031] Furthermore, assume that the harmonic disturbance torque experienced by the target spacecraft (104) is M = Asinωt.
[0032] Furthermore, assume J b >>J t And J b >>J d Therefore, the captured composite system containing the continuously variable moment of inertia damping device for stabilizing on-orbit targets described in this invention can be equivalent to, for example: Figure 5 The dynamics of the two-degree-of-freedom undamped forced vibration system shown is as follows: The dynamic equations of this system can be expressed as:
[0033] Furthermore, let its particular solution be: Furthermore, we can obtain a system of non-homogeneous equations concerning amplitudes A1 and A2: Solving this equation yields the expressions for amplitudes A1 and A2: Where: f(ω) 2 )=[(k1+k2)-J d ω 2 ](k2-J t ω 2 )-k2 2 .
[0034] Furthermore, when At that time, it can be obtained A2 = 0. Therefore: θ2 = 0. It can be seen that although the target spacecraft (104) is subjected to the disturbance torque M = Asinωt, it does not vibrate. The variable moment of inertia assembly, however, generates forced vibration with the same phase as the disturbance torque. This is equivalent to applying the disturbance torque to the variable moment of inertia assembly, while the target spacecraft (104) avoids external interference. In summary, this invention adjusts the moment of inertia J of the variable moment of inertia assembly... d (In reality, it changes the moment of inertia J of the mass block (410) relative to the rotation axis a.) v ), making The frequency ω of the disturbance torque is equal to the vibration angular displacement θ2 of the target spacecraft (104) being equal to 0, thus achieving the design requirement that the vibration of the target spacecraft is suppressed and the vibration energy input by the external disturbance torque is transferred to the variable moment of inertia component. If the frequency ω of the external disturbance torque changes, the moment of inertia J of the variable moment of inertia component can be continuously adjusted. d (In reality, it changes the moment of inertia J of the mass block (410) relative to the rotation axis a.) v It achieves broadband adaptive vibration suppression.
[0035] Furthermore, the accelerometer (318) collects the time-domain vibration signal from one side of the target spacecraft (104) and transmits it to the controller (203). The controller (203) can convert the signal from the time domain to the frequency domain through Fourier transform, thereby obtaining the frequency ω of the vibration signal. Furthermore, the desired moment of inertia J of the variable moment of inertia component relative to the rotation axis can be calculated. de The motor (406) is further controlled to rotate, thereby driving the mass block (410) to move to a suitable position, thus obtaining the desired moment of inertia J. de During the control process, the position sensor (409) can provide real-time feedback on the position information of the mass block (410), thereby realizing closed-loop control of the desired moment of inertia.
Claims
1. A stepless variable moment of inertia vibration damping device for stabilizing an on-orbit target, comprising a structural frame assembly, a variable moment of inertia assembly, a torsion spring assembly, and an electrical assembly, characterized in that: The structural frame assembly mainly consists of a capture mechanism connector, an end cap, bearing one, a space target rotating shaft, bearing two, bearing three, bearing four, a device housing, a base connector, and a bushing; the variable moment of inertia assembly includes a variable moment of inertia mechanism one, a variable moment of inertia mechanism two, a mechanism support one, a mechanism support two, a mechanism rotating shaft, a torsion spring support one, and a torsion spring support two; the torsion spring assembly includes a torsion spring two and a torsion spring one; the electrical components include an acceleration sensor and a controller; the end cap, device housing, bushing, and base connector are fixedly connected as a whole; the outer rings of bearings one and two are connected to the device housing, and the inner rings are connected to the space target rotating shaft, thus the space target rotating shaft and the device housing form a rotating pair connection, and the capture mechanism... The connecting piece is fixedly connected to the rotating shaft of the space target; the outer rings of bearings three and four are connected to the outer shell of the device, and the inner rings are connected to the rotating shaft of the mechanism, thus forming a rotating pair connection between the rotating shaft of the mechanism and the outer shell of the device; torsion spring bracket one, torsion spring bracket two, mechanism bracket one, and mechanism bracket two are all fixedly connected to the rotating shaft of the mechanism; the variable moment of inertia mechanism one is connected to mechanism bracket one, and the variable moment of inertia mechanism two is connected to mechanism bracket two; the two ends of the torsion spring one are respectively connected to the base connecting piece and the torsion spring bracket one, and can generate torsion around the rotating shaft; the two ends of the torsion spring two are respectively connected to the capture mechanism connecting piece and the torsion spring bracket two, and can generate torsion around the rotating shaft; the controller and the acceleration sensor are respectively connected to the outer shell of the device and the rotating shaft of the space target.
2. The stepless variable moment of inertia vibration reduction device for stabilizing on-orbit targets according to claim 1, characterized in that: The components of the variable moment of inertia assembly are fixedly connected as a whole and can rotate around the rotation axis. Variable moment of inertia mechanism one and variable moment of inertia mechanism two are symmetrically distributed along the rotation axis. Variable moment of inertia mechanism one and variable moment of inertia mechanism two have the same mechanical structure, which mainly includes support one, support two, lead screw, slide rail one, coupling, motor, driver, support three, position sensor, mass block, slide rail two, and base plate. Support one, support two, support three, slide rail one, and slide rail two are all connected to the base plate; the motor, driver, and position sensor are all connected to support three. The motor drives the lead screw to rotate via a coupling, thereby causing the mass block to slide up and down along slide rail one and slide rail two. The gyration radius of the mass block in both the variable moment of inertia mechanism one and the variable moment of inertia mechanism two can be steplessly adjusted under the drive of the motor, thus realizing stepless adjustment of the moment of inertia of the variable moment of inertia component relative to the rotation axis. In addition, the gyration radius of the mass block in the variable moment of inertia mechanism one and the variable moment of inertia mechanism two always remain equal to ensure that the center of mass of the stepless variable moment of inertia damping device coincides with the rotation axis, avoiding additional inertial force due to eccentricity.
3. The stepless variable moment of inertia vibration reduction device for stabilizing on-orbit targets according to claim 1, characterized in that: The accelerometer can collect time-domain vibration signals from one side of the target spacecraft and transmit them to the controller. The controller converts the time-domain signal to the frequency domain using Fourier transform, thereby obtaining the frequency of the external excitation torque. When the arithmetic square root of the ratio of the sum of the stiffnesses of torsion spring one and torsion spring two to the total moment of inertia of the variable moment of inertia assembly equals the external excitation frequency, the vibration angular displacement of the target spacecraft is zero, meaning the vibration of the target spacecraft is suppressed, and the vibration energy of the external disturbance torque input is transferred to the variable moment of inertia assembly. Based on this principle, the desired moment of inertia of the variable moment of inertia assembly can be obtained. By adjusting the rotation radius of the mass block relative to the center of rotation in the variable moment of inertia mechanism, stepless adjustment of the moment of inertia of the variable moment of inertia assembly can be achieved. When the external excitation frequency changes with factors such as the excitation source and environment, the moment of inertia of the variable moment of inertia assembly can be changed in real time according to the above principle to respond to the change in the external excitation frequency. The position sensor can provide real-time feedback on the position information of the mass block, thereby realizing closed-loop control of the moment of inertia of the variable moment of inertia assembly.
4. The stepless variable moment of inertia vibration reduction device for stabilizing on-orbit targets according to claim 1, characterized in that: The continuously variable moment of inertia damping device for stabilizing on-orbit targets is connected to the external spacecraft base or the external capture mechanism via a base connector or a capture mechanism connector.