Mass release capture ground test verification device

Abstract

This invention discloses a ground-based experimental verification device for mass block release and capture, comprising a base platform, a primary motion system, and a secondary motion system. The platform serves as the mounting foundation for the entire device. The primary motion system simulates active disturbance or motion of a freely floating object or mass block in space. The secondary motion system simulates the free motion of a freely floating object or mass block in space. Compared with other release and capture test devices, this invention employs a two-stage pendulum design, which can simultaneously verify the release and electrostatic capture of the mass block in both translational and rotational directions. The first-stage pendulum uses a dual-pivot design, effectively suppressing the interference of the other two rotational degrees of freedom on the motion of the first-stage pendulum. Two pairs of electrostatic combs are included on the opposite side of the mass block in the first-stage pendulum, which can drive the mass block's motion and set the initial conditions for the translational release of the mass block. Simultaneous capture in both translational and rotational directions is achieved, with the initial displacement and angular displacement of the mass block reaching 455 μm and 16 mrad, respectively.

Description

Technical Field

[0001] This invention belongs to the field of aerospace ground test technology, specifically a ground test verification device for mass block release and capture. Background Technology

[0002] In recent years, with the development of space science and technology, object release and capture in space has become a commonly used key technology in current and future space missions. In space gravitational wave detection, it is necessary to release and stably control a mass block at a distance of tens of thousands to millions of kilometers in space, serving as a space inertial reference. Using electrostatic control to release and capture the mass block is a crucial step for this mission to enter the space gravitational wave detection phase. Due to the complexity of the technology, conducting ground-based verification experiments is essential.

[0003] When conducting electrostatic release and capture of a mass block in a simulated space environment on the ground, it is crucial to focus on the most sensitive or critical degrees of freedom in the mission: translation and rotation in the horizontal plane. This simplified design is often used to verify release and capture mechanisms in space missions, such as satellite docking and module separation. Although there are six degrees of freedom in space, focusing on the key degrees of freedom for a specific mission can reduce the complexity of ground experiments while obtaining crucial dynamic data.

[0004] Conducting electrostatically controlled release and capture of a mass in a simulated space environment based on horizontal plane motion on the ground is a challenging task. The key lies in simulating the mass's horizontal plane motion in space while counteracting the effects of gravity. Traditionally, the mass is suspended by thin filaments (tungsten or silicon wires) to counteract vertical gravity, and then its motion is simulated in the horizontal plane. However, the pendulum motion of the suspended mass affects its horizontal plane motion, placing high demands on the length and diameter of the suspension wire. Furthermore, simultaneous release and capture of the mass with multiple degrees of freedom in the horizontal plane requires a multi-stage suspension system, further increasing the complexity of the experimental system. Summary of the Invention

[0005] This invention addresses the problems existing in the prior art by proposing a ground-based experimental verification device for the release and capture of a mass block. The purpose is to solve the problems of single-pendulum motion interference caused by traditional suspension methods and excessively high experimental system complexity during simultaneous release and capture of multiple degrees of freedom in ground-based simulated space environments for electrostatic control release and capture of mass blocks.

[0006] To solve its technical problems, the present invention proposes the following technical solutions:

[0007] A ground-based verification experimental device for mass block release and capture is characterized by comprising a base platform, a primary motion system, and a secondary motion system; the base platform serves as the mounting foundation for the entire device; the primary motion system is used to simulate active perturbation or motion of freely floating objects or mass blocks in space; and the secondary motion system is used to simulate the free motion of freely floating objects or mass blocks in space.

[0008] The basic platform includes an optical flat panel (1);

[0009] The first-stage motion system includes an actuator, a drive component, and a measuring component. The actuator consists of a first-stage pendulum, which is composed of a first-stage pendulum rod (7) and two vertical first-stage pendulum pivots (9) to achieve single-degree-of-freedom oscillation in the horizontal plane. At one end of the first-stage pendulum rod (7), a drive component is installed. The drive component consists of an electrostatic comb (10) and a displacement stage (11). The electrostatic comb (10) actively controls and drives the first-stage pendulum rod to move in the horizontal plane. Its high-voltage end is installed on the displacement stage (11), and the position of the electrostatic comb (10) is finely adjusted by the displacement stage (11). The measuring component consists of a first-stage pendulum displacement measuring sensor (8) to monitor the motion of the first-stage pendulum. At the other end of the first-stage pendulum rod (7), a second-stage pendulum elastic pivot (6) is used to connect to a mass block (5), which can rotate in the horizontal plane.

[0010] The secondary motion system includes a support mechanism, a measuring component, a control component, and an adjustment mechanism. The support mechanism consists of a mass block (5) and a second-stage pendulum elastic pivot (6), which is placed vertically. The second-stage pendulum elastic pivot (6) is connected to the mass block (5) at the end of the first-stage pendulum via the vertical second-stage pendulum elastic pivot (6), thereby inheriting the translation and rotation of the first-stage pendulum and adding a rotational degree of freedom around the second-stage pendulum elastic pivot (6). The measuring component consists of two sets of mass block displacement angle measuring sensors (3). Through signal processing, the translation of the mass block in two directions in the horizontal plane can be decoupled. Displacement and rotation in one direction; the control component consists of an electrostatic control plate (4) arranged around the mass block. By applying high voltage to the electrostatic control plate (4), controllable electrostatic force and torque are generated to realize the simulation of "release" and "capture" of the mass block; the "release" means to break free from the constraint, and the "capture" means to apply control; the adjustment mechanism consists of a three-axis displacement stage (2): the electrostatic control plate (4) is installed on the electrode cage, and the electrode cage is installed on the three-axis displacement stage (2) to realize the three-dimensional precision adjustment of the relative position between the electrostatic control plate (4) and the mass block (5).

[0011] Furthermore, the first-stage pendulum (7) is connected to the base, and the two first-stage pendulum pivots (9) of the first-stage pendulum (7) are concentric, which is used to suppress parasitic rotations around the vertical axis and around the horizontal axis, and ensure that the first-stage pendulum only swings in the horizontal plane, thereby improving the translational simulation accuracy transmitted to the mass block.

[0012] Furthermore, the number of electrostatic combs (10) is two pairs, symmetrically installed on one end of the first-stage swing arm (7).

[0013] Furthermore, the number of electrostatic control plates (4) is 8, which are evenly distributed on the four sides of the electrostatic control plates (4).

[0014] Furthermore, the motion of the mass block (5) in the horizontal plane can be either free oscillation or driven by the electrostatic comb (10).

[0015] Furthermore, the measured values ​​of the two sets of mass block displacement angle measuring sensors (3) are used to perform common mode and differential mode calculations to obtain the displacement in two directions and the rotation angle in one direction of the mass block (5) plane. Attached Figure Description

[0016] Figure 1 This is a ground verification test device for mass block release and capture according to the present invention;

[0017] Figure 2 This is a partial enlarged view of the two elastic pivots and the connection point of the first-stage pendulum of the present invention;

[0018] Figure 3 This is a schematic diagram of the horizontal movement of the first-stage pendulum of the present invention;

[0019] Figure 4 This is a partially enlarged view showing the relative positional relationship between the electrostatic comb and the displacement stage of the present invention;

[0020] Figure 5 This is a partial enlarged view of the connection between the second-stage pendulum elastic pivot and the mass block in this invention;

[0021] Figure 6 This is a partially enlarged view of the electrostatic control plate of the present invention mounted on the electrode cage;

[0022] Figure 7 This is a schematic diagram of the three-axis displacement stage driving the electrostatic control plate to move according to the present invention;

[0023] Figure 8 This is a schematic diagram illustrating how the first-stage pendulum of the present invention suppresses the other two rotational degrees of freedom;

[0024] 1: Optical flat plate; 2: Triaxial displacement stage; 3: Mass block displacement angle measuring sensor; 4: Electrostatic control plate; 5: Mass block; 6: Second-stage pendulum elastic pivot; 7: First-stage pendulum rod; 8: First-stage pendulum displacement measuring sensor; 9: First-stage pendulum pivot; 10: Electrostatic comb; 11: Displacement stage. Detailed Implementation

[0025] Innovation of this invention

[0026] 1. A composite structure of a primary pendulum and a secondary pendulum to simulate motion in space. The primary pendulum simulates active disturbance or motion, while the secondary pendulum simulates free motion. This composite pendulum structure effectively avoids the pendulum effect caused by traditional direct suspension, thus more realistically reproducing the motion state of a mass in space.

[0027] 2. Non-contact release and capture simulation based on electrostatic control. By arranging electrostatic control plates around a mass block and applying high voltage to generate controllable electrostatic force and torque, the "release" and "capture" of the mass block are simulated. This method simulates the manipulation process in space in a non-contact manner, avoiding interference introduced by mechanical contact.

[0028] 3. Decoupled motion parameter measurement scheme. Data is collected using two sets of mass block displacement and angle measurement sensors, and signal processing technology is used to decouple the translational displacement of the mass block in two directions and the rotation angle in one direction in the horizontal plane, thereby accurately obtaining its motion parameters.

[0029] 4. Suppressing parasitic rotation and improving translational accuracy. The first-stage pendulum adopts a double-elastic pivot design with concentric upper and lower parts, which effectively suppresses parasitic rotation around the vertical axis and the horizontal axis, ensuring that the first-stage pendulum only oscillates in the horizontal plane, thereby improving the translational simulation accuracy transmitted to the mass block.

[0030] In summary, this invention systematically improves the realism and control accuracy of simulating the motion behavior of a space mass block on the ground through a composite pendulum structure, electrostatic non-contact control, decoupled measurement scheme, and parasitic rotation suppression design, providing a more reliable technical means for related experiments and research.

[0031] Design difficulties of this invention

[0032] 1. One of the challenges: Gravity cancellation and realistic motion simulation. Overcoming the interference of gravity on motion in a horizontal plane is the fundamental challenge. A support structure needs to be designed to support the mass block while minimizing the effects of gravity, such as the pendulum effect, to approximate the state of free motion in space.

[0033] Solution: A compound pendulum structure is adopted, consisting of a single-stage pendulum and a two-stage pendulum. The single-stage pendulum replaces the single pendulum suspension, simulating active disturbance within the horizontal plane, thus avoiding the disturbance caused by the single pendulum suspension. The two-stage pendulum simulates free motion, making the motion of the mass block closer to the real state in space.

[0034] 2. Second Challenge: Simplifying the Multi-Degree-of-Freedom Motion Mechanism: To achieve the synchronous release and capture of the mass block's translational and rotational motions, the complexity of traditional multi-stage suspensions must be avoided. The design challenge lies in creating a simple composite structure of a single-stage and two-stage pendulum, ensuring effective motion transmission and preventing undue constraint on the rotation of the second-stage pendulum.

[0035] Solution: Focus on key degrees of freedom and simplify the system structure. The rationale for simplifying the structure is to address the specific needs of the space mission and focus on the most sensitive or critical degrees of freedom. Specific mission requirements, such as satellite docking and module separation, involve only three degrees of freedom: translation and rotation in the horizontal direction. Although space has six degrees of freedom, focusing on key degrees of freedom for a specific mission can reduce the complexity of ground-based experiments while obtaining crucial dynamic data.

[0036] 3. The third challenge: Achieving non-contact control. To avoid interference introduced by mechanical contact, electrostatic control is used for release and capture. The challenges lie in the layout design of the electrostatic electrode plates, the precise voltage control strategy, and the accurate calculation and regulation of the generated force / torque.

[0037] Solution: Simulate non-contact release and capture using electrostatic control. Controllable electrostatic force and torque are generated by electrostatic control plates, and precise adjustments are made using a three-axis displacement stage, completely avoiding mechanical contact.

[0038] 4. The fourth challenge: Suppression of parasitic motion and ensuring accuracy. In addition to the desired oscillation, the first-order pendulum may generate parasitic rotations around the vertical and horizontal axes, which will reduce the translational accuracy transmitted to the mass block.

[0039] Solution: A special first-stage pendulum pivot design, using a double elastic pivot that is concentric with the upper and lower parts, ensures that the first-stage pendulum only oscillates in the horizontal plane.

[0040] 5. Fifth Challenge: Precise Measurement and Decoupling of Multi-Degree-of-Freedom Motion Parameters: A measurement system needs to be designed to simultaneously acquire the two translational displacements and one rotational angle of the mass block. Since coupling may exist between the degrees of freedom, signal processing techniques are also required to decouple the measurement data, thereby independently and accurately extracting the motion parameters of each degree of freedom.

[0041] Solution: A decoupled motion parameter measurement scheme, which collects data through two sets of sensors, and then decouples the translational displacement and rotation angle through common-mode and differential-mode calculations.

[0042] Based on the above principles, this invention designs a mass block release and capture ground experimental verification device, such as... Figure 1-8 As shown, its features include a base platform, a primary motion system, and a secondary motion system; the base platform serves as the installation foundation for the entire device; the primary motion system is used to simulate active disturbance or motion of freely floating objects or mass blocks in space; the secondary motion system is used to simulate the free motion of freely floating objects or mass blocks in space.

[0043] The basic platform includes an optical flat panel 1;

[0044] like Figure 1 , Figure 2 , Figure 4 As shown, the primary motion system includes an actuator, a drive component, and a measuring component. The actuator consists of a first-stage pendulum 7 and two vertical first-stage pendulum pivots 9, enabling single-degree-of-freedom oscillation in the horizontal plane. A drive component is installed at one end of the first-stage pendulum 7, consisting of an electrostatic comb 10 and a displacement stage 11. The electrostatic comb 10 actively controls and drives the first-stage pendulum to move in the horizontal plane, and its high-voltage end is mounted on the displacement stage 11, which finely adjusts the position of the electrostatic comb 10. The measuring component consists of a first-stage pendulum displacement sensor 8, used to monitor the motion of the first-stage pendulum. At the other end of the first-stage pendulum 7, a second-stage pendulum elastic pivot 6 connects to a mass block 5, which can rotate in the horizontal plane.

[0045] like Figure 1 , Figure 5 As shown, the secondary motion system includes a support mechanism, a measuring component, a control component, and an adjustment mechanism. The support mechanism consists of a mass block 5 and a second-stage pendulum elastic pivot 6, which is placed vertically. The second-stage pendulum elastic pivot 6 is connected to the mass block 5 at the end of the first-stage pendulum, thus inheriting the translation and rotation of the first-stage pendulum and adding a rotational degree of freedom about the second-stage pendulum elastic pivot (6). The measuring component consists of two sets of mass block displacement angle measuring sensors 3. Through signal processing, the displacement angles of the mass block in two directions in the horizontal plane can be decoupled. The control component consists of a translational displacement and a rotation angle in one direction. It is composed of an electrostatic control plate 4 arranged around the mass block. By applying high voltage to the electrostatic control plate 4, a controllable electrostatic force and torque are generated to simulate the "release" and "capture" of the mass block. The "release" means breaking free from the constraint, and the "capture" means applying control. The adjustment mechanism consists of a three-axis displacement stage 2: the electrostatic control plate 4 is mounted on the electrode cage, and the electrode cage is mounted on the three-axis displacement stage 2 to achieve three-dimensional precision adjustment of the relative position between the electrostatic control plate 4 and the mass block 5.

[0046] like Figure 3As shown, the first-stage pendulum 7 is connected to the base, and the two first-stage pendulum pivots 9 of the first-stage pendulum 7 are concentric, which is used to suppress parasitic rotations around the vertical axis and around the horizontal axis, ensuring that the first-stage pendulum only swings in the horizontal plane, thereby improving the translational simulation accuracy transmitted to the mass block.

[0047] Supplementary Note 1

[0048] 1) The translation of the mass block is not caused by the rigid translation of the first-stage pendulum 7, but is approximated by the small-angle horizontal swing of the first-stage pendulum and transmitted to the mass block through the elastic pivot of the second-stage pendulum.

[0049] 2) Figure 3 Although the 'direction of rotation' is shown, this indicates that the first-stage pendulum 7 is oscillating back and forth at a small angle in the horizontal plane. This is important because a small-angle oscillation is approximately a translation.

[0050] In summary, the translational motion of the ground-based simulated space mass block 5 is achieved through the coordinated operation of a primary motion system and a secondary motion system. The specific process is as follows:

[0051] A. The primary motion system provides the basic motion: The primary motion system consists of a first-stage pendulum 7 and an electrostatic comb 10 / displacement stage 11. The electrostatic comb 10, through fine-tuning of the displacement stage 11, drives the first-stage pendulum 7 to reciprocate at a small angle around two concentric vertical pivots 9 in the horizontal plane. Because the swing angle is very small, the motion trajectory of the end of the pendulum can be approximated as a straight line, thus producing a translational effect.

[0052] B. The secondary motion system inherits and transforms motion: The end of the first-stage pendulum 7 is connected to the mass block 5 through the elastic pivot 6 of the second-stage pendulum. The small-angle swing of the first-stage pendulum is transmitted to the mass block through this elastic pivot, causing it to achieve horizontal translation.

[0053] C. Degrees of freedom and release of the mass block: The mass block 5 itself has translational and rotational degrees of freedom in the horizontal plane. Driven by the first-stage pendulum, the mass block mainly achieves translational motion. The electrostatic control plates (4) arranged around the mass block can realize the "release" and "capture" of the mass block. After release, the mass block moves approximately freely in the horizontal plane, simulating the floating state in space.

[0054] In summary, the translational motion of the mass block essentially originates from the small-angle oscillation (approximate translation) of the first-stage pendulum, and is transmitted through the elastic pivot of the second-stage pendulum, combined with electrostatic control to achieve simulation.

[0055] like Figure 4 As shown, there are two pairs of electrostatic combs 10, which are symmetrically installed at one end of the first-stage swing arm 7.

[0056] like Figure 6As shown, there are 8 electrostatic control plates 4, which are evenly distributed on the four sides of the electrostatic control plates 4.

[0057] like Figure 5 As shown, the motion of the mass block 5 in the horizontal plane can be either free oscillation or driven by the electrostatic comb 10.

[0058] like Figure 1 As shown, the measurements from the two sets of mass block displacement angle measuring sensors 3 are processed using common-mode and differential-mode operations to obtain the displacement in two directions and the rotation angle in one direction within the plane of the mass block 5.

[0059] It should be emphasized that the above specific embodiments are merely explanations of the present invention and are not intended to limit the present invention. After reading this specification, those skilled in the art can make modifications to the above embodiments without contributing any inventive step, but as long as they are within the scope of the claims of the present invention, they are protected by patent law.

Claims

1. A ground-based verification experimental apparatus for mass block release and capture, characterized in that, It includes a basic platform, a primary motion system, and a secondary motion system; the basic platform serves as the mounting base for the entire device; the primary motion system is used to simulate active disturbance or motion of freely floating objects or masses in space; the secondary motion system is used to simulate the free motion of freely floating objects or masses in space. The basic platform includes an optical flat panel (1); The first-stage motion system includes an actuator, a drive component, and a measuring component. The actuator consists of a first-stage pendulum (7) and two vertical first-stage pendulum pivots (9), enabling single-degree-of-freedom oscillation in the horizontal plane. A drive component is installed at one end of the first-stage pendulum (7), consisting of an electrostatic comb (10) and a displacement stage (11). The electrostatic comb (10) actively controls and drives the first-stage pendulum (7) to move in the horizontal plane. Its high-voltage end is installed on the displacement stage (11), which finely adjusts the position of the electrostatic comb (10). The measuring component consists of a first-stage pendulum displacement measuring sensor (8), used to monitor the movement of the first-stage pendulum (7). At the other end of the first-stage pendulum (7), a second-stage pendulum elastic pivot (6) is used to connect to a mass block (5), which can rotate in the horizontal plane. The secondary motion system includes a support mechanism, a measuring component, a control component, and an adjustment mechanism. The support mechanism consists of a mass block (5) and a second-stage pendulum elastic pivot (6), which is placed vertically. The second-stage pendulum elastic pivot (6) is connected to the mass block (5) at the end of the first-stage pendulum rod (7) through the vertical second-stage pendulum elastic pivot (6), thereby inheriting the translation and rotation of the first-stage pendulum rod (7) and adding a rotational degree of freedom around the second-stage pendulum elastic pivot (6). The measuring component consists of two sets of mass block displacement angle measuring sensors (3). Through signal processing, the two directions of the mass block in the horizontal plane can be decoupled. The control component consists of an electrostatic control plate (4) arranged around the mass block. By applying high voltage to the electrostatic control plate (4), a controllable electrostatic force and torque are generated to simulate the "release" and "capture" of the mass block. The "release" means to break free from the constraint, and the "capture" means to apply control. The adjustment mechanism consists of a three-axis displacement stage (2): the electrostatic control plate (4) is installed on the electrode cage, and the electrode cage is installed on the three-axis displacement stage (2) to realize the three-dimensional precision adjustment of the relative position between the electrostatic control plate (4) and the mass block (5).

2. The mass block release and capture ground verification experimental device according to claim 1, characterized in that: The first-stage pendulum (7) is connected to the base. The two first-stage pendulum pivots (9) of the first-stage pendulum (7) are concentric, which is used to suppress parasitic rotation around the vertical axis and around the horizontal axis, and ensure that the first-stage pendulum (7) only swings in the horizontal plane, thereby improving the translational simulation accuracy transmitted to the mass block.

3. The mass block release and capture ground verification experimental device according to claim 1, characterized in that: The number of electrostatic combs (10) is two pairs, which are symmetrically installed at one end of the first-stage swing arm (7).

4. The mass block release and capture ground verification experimental device according to claim 1, characterized in that: The number of electrostatic control plates (4) is 8, which are evenly distributed on the four sides of the electrostatic control plates (4).

5. The mass block release and capture ground verification experimental device according to claim 1, characterized in that: The motion of the mass block (5) in the horizontal plane can be either free oscillation or driven by the electrostatic comb (10).

6. The mass block release and capture ground verification experimental device according to claim 1, characterized in that: The measurements from the two sets of mass block displacement angle measuring sensors (3) are used to perform common-mode and differential-mode calculations to obtain the displacement in two directions and the rotation angle in one direction of the mass block (5) in the plane.

7. The mass block release and capture ground verification experimental device according to claim 1, characterized in that: The initial displacement and angular displacement of the mass block can reach 455 μm and 16 mrad, respectively.

Images