Microgravity simulation device and method

Abstract

The invention discloses a microgravity simulation device and method. The device comprises a mounting base, a vertical mounting bracket, a universal ring group and an experimental platform, the mounting base is used for providing a stable mounting and operation base for microgravity simulation; the number of the vertical mounting brackets is two, and the vertical mounting brackets are arranged at the two ends of the mounting base and are used for mounting the universal ring group; the universal ring group comprises an external universal ring, a middle universal ring and an internal universal ring and is used for providing a three-dimensional rotating environment for an object to be tested; an experiment platform is mounted on the internal universal ring; the experiment platform is used for providing an installation space for an object to be tested.

Description

Technical Field

[0001] The present invention relates to the fields of space technology and control simulation, and in particular to a microgravity simulation device and method. Background Art

[0002] When preparing for long-duration space missions of more than 3 to 6 months, the medical and psychological aspects of the mission crew become an important aspect that needs attention. Considering the space confinement and psychological loneliness that personnel will experience, especially the potential hazards faced when performing missions from low-Earth orbit (LEO) to the Moon and Mars, it will bring great challenges and risks to human performance. These risks may come from a variety of factors: such as boredom, boredom, anxiety, self-management and increased dependence of crew members on each other, interpersonal tension, confined spaces, long flight times, mechanical failures, and unexpected physical illness problems. All of these aspects require a large number of relevant technologies in various fields of space science, which need to be obtained through human space simulators. These technologies are crucial to the development of future scientific knowledge and progress in space exploration.

[0003] Currently, simulations of space environments include free-fall machines and parabolic flights of airplanes. The working principle of a free-fall machine (FFM) is free fall. In an FFM, the maximum free-fall period is about 900 milliseconds (ms), and is interrupted by an acceleration of 20g for about 20 to 80ms. FFM is a good weightlessness simulator for many biological samples. However, this technology also has some disadvantages, such as the short duration of microgravity, which makes it impossible to study the effects of microgravity on system objects, and experimenters cannot conduct load-bearing experiments. Using an airplane to do a parabolic flight can achieve a microgravity state of 25 seconds. A typical flight lasts 2-3 hours, and the passengers and experimental subjects start at an altitude of about 7 kilometers. The aircraft climbs rapidly at a 45-degree angle (ascending phase), then changes to a parabolic flight (level flight phase), and finally descends rapidly at a 45-degree angle (descending phase). The passengers and test subjects will be subjected to 2-2.5g of hypergravity during the ascent and descent phases, and 10g of hypergravity will be obtained at an altitude of 7.3km to 10.4km during the parabolic level flight phase. -2 g-level microgravity for more than 15 seconds. Aircraft cannot achieve the high-quality microgravity conditions that can be created by a drop tower, however, it can be used to study the effects of microgravity on the cardiovascular system of animals and humans. Parabolic flights by aircraft are expensive and complex to implement.

[0004] How to develop and manufacture relevant equipment that can simulate microgravity conditions for a long time based on the ground environment is a problem that needs to be solved at present. Summary of the invention

[0005] The present invention mainly solves the problem of how to develop and manufacture related devices that can simulate microgravity conditions for a long time based on the ground environment. The present invention discloses a microgravity simulation device and method.

[0006] In a first aspect of an embodiment of the present invention, a microgravity simulation device is disclosed, comprising: a mounting base, a vertical mounting bracket, a universal ring set, and an experimental platform;

[0007] The mounting base is used to provide a stable mounting and operating base for microgravity simulation;

[0008] The vertical mounting brackets, which are two in number and are arranged at both ends of the mounting base, are used to mount the universal ring assembly;

[0009] The universal ring set includes an outer universal ring, a middle universal ring and an inner universal ring, and is used to provide a three-dimensional rotation environment for the object to be tested;

[0010] An experimental platform is installed on the internal universal ring;

[0011] The experimental platform is used to provide an installation space for the items to be tested.

[0012] The first connection point and the second connection point on the external universal ring are respectively connected to the upper ends of the two vertical mounting brackets through the first bearing, and the connecting line of the first connection point and the second connection point is the diameter of the external universal ring;

[0013] The third connection point and the fourth connection point on the middle universal ring are respectively connected to the first connection point and the second connection point on the outer universal ring through the second bearing;

[0014] The fifth connection point and the sixth connection point on the middle universal ring are respectively connected to the seventh connection point and the eighth connection point on the inner universal ring through the third bearing;

[0015] The connecting line of the third connection point and the fourth connection point on the middle universal ring, and the connecting line of the fifth connection point and the sixth connection point on the middle universal ring are both the diameter of the middle universal ring;

[0016] The ninth connection point and the tenth connection point on the inner universal ring are respectively connected to the experimental platform through the fourth bearing;

[0017] The line connecting the seventh connection point and the eighth connection point on the inner universal ring, and the line connecting the ninth connection point and the tenth connection point on the inner universal ring, are the diameter of the inner universal ring;

[0018] A driving motor is arranged inside each bearing; the driving motor is used to drive the bearing to rotate.

[0019] The microgravity simulation device also includes a microgravity three-axis acceleration sensor, a drive module and a control module;

[0020] The microgravity three-axis acceleration sensor is installed on the experimental platform and is used to measure and obtain a motion value sequence set of the experimental platform; the motion value sequence set includes a gravity value sequence, an X-axis acceleration sequence, a Y-axis acceleration sequence and a Z-axis acceleration sequence;

[0021] The driving module is used to output a corresponding motor driving value to the driving motor of each bearing according to the motor driving value set;

[0022] The control module is used to perform feedback calculation processing on the received motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment.

[0023] The control module performs feedback calculation processing on the received motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment, including:

[0024] The control module performs microgravity evaluation processing on the received motion value sequence set to obtain an evaluation value sequence;

[0025] The evaluation value sequence, the motion value sequence set and the motor drive value set of the current time period are subjected to fusion feedback calculation processing to obtain the motor drive value set of the next moment.

[0026] In a second aspect of the embodiment of the present invention, a microgravity simulation method is disclosed, which is implemented by using the microgravity simulation device, and includes:

[0027] S1, using the motors on the bearings of the universal ring assembly to drive the universal rings to rotate, so that the object to be tested on the experimental platform is in a microgravity environment;

[0028] S2, using the microgravity three-axis acceleration sensor to measure and obtain a set of motion value sequences of the experimental platform;

[0029] S3, using the drive module to output a corresponding motor drive value to each bearing according to the motor drive value set;

[0030] S4, using the control module to perform feedback calculation processing on the received motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment.

[0031] The step of performing feedback calculation processing on the received motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment includes:

[0032] S41, performing microgravity evaluation processing on the received motion value sequence set to obtain an evaluation value sequence;

[0033] S42, performing fusion feedback calculation processing on the evaluation value sequence, the motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment.

[0034] The step of performing microgravity evaluation processing on the received motion value sequence set to obtain an evaluation value sequence includes:

[0035] S411, obtaining the standard gravity value and the standard acceleration values ​​of the X-axis, Y-axis and Z-axis under the standard gravity;

[0036] S412, performing subtraction processing on each sequence in the received motion value sequence set and a standard value of a corresponding type to obtain a corresponding difference sequence;

[0037] S413, constructing a difference matrix using all the difference sequences; the row vectors in the difference matrix are the difference sequences;

[0038] S414, performing cross-covariance calculation processing on the difference sequence to obtain a cross-covariance matrix;

[0039] S415, performing eigenvalue decomposition processing on the difference sequence to obtain an eigenvalue sequence and an eigenvector set;

[0040] S416, performing fusion calculation processing on the cross-covariance matrix, eigenvalue sequence and eigenvector set to obtain an evaluation value sequence.

[0041] The expression of the fusion calculation process is:

[0042]

[0043] Among them, q i is the i-th element in the evaluation value sequence, T i () represents the i-th order polynomial of the first kind of Chebyshev polynomial, λ i represents the mean of the i-th eigenvector, μ i represents the i-th eigenvalue, v i represents the mean of the i-th row elements in the cross-covariance matrix.

[0044] The step of performing fusion feedback calculation processing on the evaluation value sequence, the motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment includes:

[0045] S421, obtaining the standard gravity value and the standard acceleration values ​​of the X-axis, Y-axis, and Z-axis under the standard gravity;

[0046] S422, performing subtraction processing on each sequence in the received motion value sequence set and a standard value of a corresponding type to obtain a corresponding difference sequence;

[0047] S423, performing feature transformation processing on each difference sequence to obtain a corresponding difference feature value;

[0048] S424, constructing a difference feature value sequence using all the difference feature values;

[0049] S425, performing feedback calculation processing on the evaluation value sequence and the difference feature value sequence to obtain a fusion feedback amount sequence;

[0050] S426, performing feedback fusion calculation processing on the fused feedback amount sequence and the motor drive value set of the current time period to obtain the motor drive value set of the next moment.

[0051] The expression of the feedback calculation process is:

[0052]

[0053] Wherein, pi represents the i-th fusion feedback quantity in the fusion feedback quantity sequence;

[0054] The expression of the feedback fusion calculation process is:

[0055]

[0056] Among them, f i (t) represents the driving value of the motor of the i-th bearing at the current time t, f i (t+1) represents the driving value of the motor of the i-th bearing at time t+1, the value of i is 1, 2, 3 or 4, and η is a preset proportional constant.

[0057] The beneficial effects of the present invention are:

[0058] The present invention discloses a microgravity simulation device and method, and realizes a related device developed and manufactured based on a ground environment and capable of simulating microgravity conditions for a long time.

[0059] In the process of realizing the microgravity mode, the present invention measures the gravity value and the acceleration value in real time, and introduces a feedback control mechanism to perform feedback calculation processing on the received motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set at the next moment, thereby improving the durability and realism of microgravity.

[0060] In the feedback calculation process, the present invention first performs microgravity evaluation processing on the received motion value sequence set to obtain an evaluation value sequence; and performs fusion feedback calculation processing on the evaluation value sequence, the motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment. Through the two-step calculation method, the accuracy and real-time performance of the feedback processing are guaranteed, and the feedback effect is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] Figure 1 1 is a flow chart for implementing the method of the present invention;

[0062] Figure 2 It is a composition diagram of the device of the present invention;

[0063] Figure 3 It is a general schematic diagram of the device of the present invention. DETAILED DESCRIPTION

[0064] In order to better understand the content of the present invention, an embodiment is given here.

[0065] Figure 1 1 is a flow chart for implementing the method of the present invention; Figure 2 It is a composition diagram of the device of the present invention; Figure 3 is a general schematic diagram of the device of the present invention, Figure 3 In the experiment, the sample table is the experimental platform, and the entire microgravity simulation device can be placed on the instrument cabinet.

[0066] In a first aspect of an embodiment of the present invention, a microgravity simulation device is disclosed, comprising: a mounting base, a vertical mounting bracket, a universal ring set, and an experimental platform;

[0067] The mounting base is used to provide a stable mounting and operating base for microgravity simulation;

[0068] The vertical mounting brackets, which are two in number and are arranged at both ends of the mounting base, are used to mount the universal ring assembly;

[0069] The universal ring set includes an outer universal ring, a middle universal ring and an inner universal ring, and is used to provide a three-dimensional rotation environment for the object to be tested;

[0070] An experimental platform is installed on the internal universal ring;

[0071] The experimental platform is used to provide an installation space for the items to be tested;

[0072] The first connection point and the second connection point on the external universal ring are respectively connected to the upper ends of the two vertical mounting brackets through the first bearing, and the line connecting the first connection point and the second connection point is the diameter of the external universal ring; the first bearing includes two sub-bearings, which are respectively connected to the first connection point and the second connection point; the second bearing, the third bearing, and the fourth bearing are similar to the first bearing and all include sub-bearings connected to two corresponding connection points.

[0073] The third connection point and the fourth connection point on the middle universal ring are respectively connected to the first connection point and the second connection point on the outer universal ring through the second bearing;

[0074] The fifth connection point and the sixth connection point on the middle universal ring are respectively connected to the seventh connection point and the eighth connection point on the inner universal ring through the third bearing;

[0075] The connecting line of the third connection point and the fourth connection point on the middle universal ring, and the connecting line of the fifth connection point and the sixth connection point on the middle universal ring are both the diameter of the middle universal ring;

[0076] The ninth connection point and the tenth connection point on the inner universal ring are respectively connected to the experimental platform through the fourth bearing;

[0077] The line connecting the seventh connection point and the eighth connection point on the inner universal ring, and the line connecting the ninth connection point and the tenth connection point on the inner universal ring, are the diameter of the inner universal ring;

[0078] A driving motor is arranged inside each bearing; the driving motor is used to drive the bearing to rotate;

[0079] The microgravity simulation device also includes a microgravity three-axis acceleration sensor, a drive module and a control module;

[0080] The microgravity three-axis acceleration sensor is installed on the experimental platform and is used to measure and obtain a motion value sequence set of the experimental platform; the motion value sequence set includes a gravity value sequence, an X-axis acceleration sequence, a Y-axis acceleration sequence and a Z-axis acceleration sequence;

[0081] The driving module is used to output a corresponding motor driving value to the driving motor of each bearing according to the motor driving value set;

[0082] The control module is used to perform feedback calculation processing on the received motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment;

[0083] The control module performs feedback calculation processing on the received motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment, including:

[0084] The control module performs microgravity evaluation processing on the received motion value sequence set to obtain an evaluation value sequence;

[0085] Performing fusion feedback calculation processing on the evaluation value sequence, the motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment;

[0086] The step of performing microgravity evaluation processing on the received motion value sequence set to obtain an evaluation value sequence includes:

[0087] Obtain the standard gravity value and the standard acceleration values ​​of the X-axis, Y-axis, and Z-axis under standard gravity;

[0088] Subtracting each sequence in the received motion value sequence set from a standard value of a corresponding type to obtain a corresponding difference sequence;

[0089] Using all the difference sequences, a difference matrix is ​​constructed; the row vectors in the difference matrix are the difference sequences;

[0090] Performing cross-covariance calculation processing on the difference sequence to obtain a cross-covariance matrix;

[0091] Performing eigenvalue decomposition processing on the difference sequence to obtain an eigenvalue sequence and an eigenvector set;

[0092] Performing fusion calculation processing on the cross-covariance matrix, the eigenvalue sequence and the eigenvector set to obtain an evaluation value sequence;

[0093] The expression of the fusion calculation process is:

[0094]

[0095] Among them, q i is the i-th element in the evaluation value sequence, T i () represents the i-th order polynomial of the first kind of Chebyshev polynomial, λ i represents the mean of the i-th eigenvector, μ i represents the i-th eigenvalue, v i represents the mean of the i-th row elements in the cross-covariance matrix;

[0096] The step of performing fusion feedback calculation processing on the evaluation value sequence, the motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment includes:

[0097] Obtain the standard gravity value and the standard acceleration values ​​of the X-axis, Y-axis, and Z-axis under standard gravity;

[0098] Subtracting each sequence in the received motion value sequence set from a standard value of a corresponding type to obtain a corresponding difference sequence;

[0099] Perform feature transformation on each difference sequence to obtain the corresponding difference feature value;

[0100] Using all the difference eigenvalues ​​to construct a difference eigenvalue sequence;

[0101] Performing feedback calculation processing on the evaluation value sequence and the difference characteristic value sequence to obtain a fusion feedback amount sequence;

[0102] The expression of the feedback calculation process is:

[0103]

[0104] Among them, p i represents the i-th fusion feedback quantity in the fusion feedback quantity sequence;

[0105] Performing feedback fusion calculation processing on the fused feedback quantity sequence and the motor drive value set of the current time period to obtain the motor drive value set of the next moment;

[0106] The motor drive value set includes four drive values, which are respectively used to drive four drive motors of the first to fourth bearings.

[0107] The expression of the feedback fusion calculation process is:

[0108]

[0109] Among them, f i (t) represents the driving value of the motor of the i-th bearing at the current time t, f i (t+1) represents the driving value of the motor of the i-th bearing at time t+1, the value of i is 1, 2, 3 or 4, and η is a preset proportional constant, whose value can be 20.

[0110] The expression of the feature transformation process is:

[0111]

[0112] Among them, C iis the eigenvalue of the i-th difference sequence, and is also the i-th difference eigenvalue of the difference eigenvalue sequence. The integral range is -∞~∞, l represents the element number, τ is the deviation number, Ω is the discrete frequency variable corresponding to l, θ is the angle variable, k(θ,τ)=A(θ)g(θ,τ), k(θ,τ) is the first kernel function, g(θ,τ) is the second kernel function, a=0.001,β=50,A(θ) is the Gaussian function about θ,x i () is the i-th difference sequence, and * indicates conjugation.

[0113] The cross-covariance calculation process is performed by taking the row vectors in the difference sequence as samples for calculation;

[0114] The standard gravity value is the standard gravity value of the earth; the standard acceleration values ​​of the X-axis, Y-axis, and Z-axis under the standard gravity are the standard acceleration values ​​of the X-axis, Y-axis, and Z-axis under the standard gravity value of the earth.

[0115] The motor driving value is the voltage or current of the driving motor;

[0116] The microgravity simulation device includes a sturdy base frame, two sets (eventually three sets) of universal rings, and an experimental platform installed at the center of the inner ring. These universal rings are installed using bearings inside and outside nesting, and are driven separately by independent drive devices (including programmable motors and motor controllers). The motor is controlled based on the feedback signal generated by the encoder installed on the motor shaft and the zero position sensor installed in the universal ring. The microgravity simulation experimental prototype will be installed in the integrated environmental chamber to test the functional volume "exposed" to simulated microgravity conditions and the operating angular velocity of the independent drive ring, and finally achieve an acceptable level of simulated microgravity. The displayed micro-electromechanical system (MEMS) acceleration sensor system will be selected for use on the sample stage of the laboratory-scale microgravity simulator experimental prototype to collect microgravity acceleration data. The sensor demonstrates a new design method for microgravity simulation by randomly changing the direction of the gravity vector in three directions of motion (3D).

[0117] The microgravity three-axis acceleration sensor includes a gravity sensor and an accelerometer sensor. The gravity sensor can be implemented by a MEMS accelerometer sensor. The MEMS accelerometer sensor has inherent advantages such as smaller size and lighter weight. The sensitivity of the sensor is less than 10 -6 ×g, with a package size less than 8 cubic inches, weighing less than 0.25 pounds, and consuming less than 1 watt. The MEMS accelerometer, combined with the prototype electronics, produces a universal 0.1-25 Hz microgravity resolution that can be extended to 1500 Hz.

[0118] A second aspect of the embodiments of the present invention discloses a microgravity simulation method, which is implemented by using the microgravity simulation device, and includes:

[0119] S1, using the motors on the bearings of the universal ring assembly to drive the universal rings to rotate, so that the object to be tested on the experimental platform is in a microgravity environment;

[0120] S2, using the microgravity three-axis acceleration sensor to measure and obtain a set of motion value sequences of the experimental platform;

[0121] S3, using the drive module to output a corresponding motor drive value to each bearing according to the motor drive value set;

[0122] S4, using the control module to perform feedback calculation processing on the received motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment;

[0123] The step of performing feedback calculation processing on the received motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment includes:

[0124] S41, performing microgravity evaluation processing on the received motion value sequence set to obtain an evaluation value sequence;

[0125] S42, performing fusion feedback calculation processing on the evaluation value sequence, the motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment;

[0126] The step of performing microgravity evaluation processing on the received motion value sequence set to obtain an evaluation value sequence includes:

[0127] S411, obtaining the standard gravity value and the standard acceleration values ​​of the X-axis, Y-axis and Z-axis under the standard gravity;

[0128] S412, performing subtraction processing on each sequence in the received motion value sequence set and a standard value of a corresponding type to obtain a corresponding difference sequence;

[0129] S413, constructing a difference matrix using all the difference sequences; the row vectors in the difference matrix are the difference sequences;

[0130] S414, performing cross-covariance calculation processing on the difference sequence to obtain a cross-covariance matrix;

[0131] S415, performing eigenvalue decomposition processing on the difference sequence to obtain an eigenvalue sequence and an eigenvector set;

[0132] S416, performing fusion calculation processing on the cross-covariance matrix, the eigenvalue sequence and the eigenvector set to obtain an evaluation value sequence;

[0133] The expression of the fusion calculation process is:

[0134]

[0135] Among them, q i is the i-th element in the evaluation value sequence, T i () represents the i-th order polynomial of the first kind of Chebyshev polynomial, λ i represents the mean of the i-th eigenvector, μ i represents the i-th eigenvalue, v i represents the mean of the i-th row elements in the cross-covariance matrix;

[0136] The step of performing fusion feedback calculation processing on the evaluation value sequence, the motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment includes:

[0137] S421, obtaining the standard gravity value and the standard acceleration values ​​of the X-axis, Y-axis, and Z-axis under the standard gravity;

[0138] S422, performing subtraction processing on each sequence in the received motion value sequence set and a standard value of a corresponding type to obtain a corresponding difference sequence;

[0139] S423, performing feature transformation processing on each difference sequence to obtain a corresponding difference feature value;

[0140] S424, constructing a difference feature value sequence using all the difference feature values;

[0141] S425, performing feedback calculation processing on the evaluation value sequence and the difference feature value sequence to obtain a fusion feedback amount sequence;

[0142] The expression of the feedback calculation process is:

[0143]

[0144] Wherein, pi represents the i-th fusion feedback quantity in the fusion feedback quantity sequence;

[0145] S426, performing feedback fusion calculation processing on the fused feedback amount sequence and the motor drive value set of the current time period to obtain the motor drive value set of the next moment;

[0146] The expression of the feedback fusion calculation process is:

[0147]

[0148] Among them, f i (t) represents the driving value of the motor of the i-th bearing at the current time t, f i (t+ 1 ) represents the driving value of the motor of the i-th bearing at time t+1, the value of i is 1, 2, 3 or 4, and η is a preset proportional constant, which can be 20.

[0149] The expression of the feature transformation process is:

[0150]

[0151] Among them, C i is the eigenvalue of the i-th difference sequence, and is also the i-th difference eigenvalue of the difference eigenvalue sequence. The integral range is -∞~∞, l represents the element number, τ is the deviation number, Ω is the discrete frequency variable corresponding to l, θ is the angle variable, k(θ,τ)=A(θ)g(θ,τ), k(θ,τ) is the first kernel function, g(θ,τ) is the second kernel function, a=0.001,β=50,A(θ) is the Gaussian function about θ,x i () is the i-th difference sequence, and * indicates conjugation.

[0152] The above description is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention should be included in the scope of the claims of the present invention.

Claims

1. A microgravity simulation device, characterized in that: include: Mounting base, vertical mounting bracket, universal ring set, experimental platform; The mounting base is used to provide a stable mounting and operating base for microgravity simulation; The vertical mounting brackets, which are two in number and are arranged at both ends of the mounting base, are used to mount the universal ring assembly; The universal ring set includes an outer universal ring, a middle universal ring and an inner universal ring, and is used to provide a three-dimensional rotation environment for the object to be tested; An experimental platform is installed on the internal universal ring; The experimental platform is used to provide an installation space for the items to be tested.

2. The microgravity simulation device according to claim 1, characterized in that: The first connection point and the second connection point on the external universal ring are respectively connected to the upper ends of the two vertical mounting brackets through the first bearing, and the connecting line of the first connection point and the second connection point is the diameter of the external universal ring; The third connection point and the fourth connection point on the middle universal ring are respectively connected to the first connection point and the second connection point on the outer universal ring through the second bearing; The fifth connection point and the sixth connection point on the middle universal ring are respectively connected to the seventh connection point and the eighth connection point on the inner universal ring through the third bearing; The connecting line of the third connection point and the fourth connection point on the middle universal ring, and the connecting line of the fifth connection point and the sixth connection point on the middle universal ring are both the diameter of the middle universal ring; The ninth connection point and the tenth connection point on the inner universal ring are respectively connected to the experimental platform through the fourth bearing; The line connecting the seventh connection point and the eighth connection point on the inner universal ring, and the line connecting the ninth connection point and the tenth connection point on the inner universal ring, are the diameter of the inner universal ring; A driving motor is arranged inside each bearing; the driving motor is used to drive the bearing to rotate.

3. The microgravity simulation device according to claim 1, characterized in that: The microgravity simulation device also includes a microgravity three-axis acceleration sensor, a drive module and a control module; The microgravity three-axis acceleration sensor is installed on the experimental platform and is used to measure and obtain a motion value sequence set of the experimental platform; the motion value sequence set includes a gravity value sequence, an X-axis acceleration sequence, a Y-axis acceleration sequence and a Z-axis acceleration sequence; The driving module is used to output a corresponding motor driving value to the driving motor of each bearing according to the motor driving value set; The control module is used to perform feedback calculation processing on the received motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment.

4. The microgravity simulation device according to claim 3, characterized in that: The control module performs feedback calculation processing on the received motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment, including: The control module performs microgravity evaluation processing on the received motion value sequence set to obtain an evaluation value sequence; The evaluation value sequence, the motion value sequence set and the motor drive value set of the current time period are subjected to fusion feedback calculation processing to obtain the motor drive value set of the next moment.

5. A microgravity simulation method, characterized in that: The method is implemented by using the microgravity simulation device according to any one of claims 2 to 4, comprising: S1, using the motors on the bearings of the universal ring assembly to drive the universal rings to rotate, so that the object to be tested on the experimental platform is in a microgravity environment; S2, using the microgravity three-axis acceleration sensor to measure and obtain a set of motion value sequences of the experimental platform; S3, using the drive module to output a corresponding motor drive value to each bearing according to the motor drive value set; S4, using the control module to perform feedback calculation processing on the received motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment.

6. The microgravity simulation method according to claim 5, characterized in that: The step of performing feedback calculation processing on the received motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment includes: S41, performing microgravity evaluation processing on the received motion value sequence set to obtain an evaluation value sequence; S42, performing fusion feedback calculation processing on the evaluation value sequence, the motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment.

7. The microgravity simulation method according to claim 6, characterized in that: The step of performing microgravity evaluation processing on the received motion value sequence set to obtain an evaluation value sequence includes: S411, obtaining the standard gravity value and the standard acceleration values ​​of the X-axis, Y-axis and Z-axis under the standard gravity; S412, performing subtraction processing on each sequence in the received motion value sequence set and a standard value of a corresponding type to obtain a corresponding difference sequence; S413, constructing a difference matrix using all the difference sequences; the row vectors in the difference matrix are the difference sequences; S414, performing cross-covariance calculation processing on the difference sequence to obtain a cross-covariance matrix; S415, performing eigenvalue decomposition processing on the difference sequence to obtain an eigenvalue sequence and an eigenvector set; S416, performing fusion calculation processing on the cross-covariance matrix, eigenvalue sequence and eigenvector set to obtain an evaluation value sequence.

8. The microgravity simulation method according to claim 7, characterized in that: The expression of the fusion calculation process is: Among them, q i is the i-th element in the evaluation value sequence, T i () represents the i-th order polynomial of the first kind of Chebyshev polynomial, λ i represents the mean of the i-th eigenvector, μ i represents the i-th eigenvalue, v i represents the mean of the i-th row elements in the cross-covariance matrix.

9. The microgravity simulation method according to claim 8, characterized in that: The step of performing fusion feedback calculation processing on the evaluation value sequence, the motion value sequence set and the motor drive value set of the current time period to obtain the motor drive value set of the next moment includes: S421, obtaining the standard gravity value and the standard acceleration values ​​of the X-axis, Y-axis, and Z-axis under the standard gravity; S422, performing subtraction processing on each sequence in the received motion value sequence set and a standard value of a corresponding type to obtain a corresponding difference sequence; S423, performing feature transformation processing on each difference sequence to obtain a corresponding difference feature value; S424, constructing a difference feature value sequence using all the difference feature values; S425, performing feedback calculation processing on the evaluation value sequence and the difference feature value sequence to obtain a fusion feedback amount sequence; S426, performing feedback fusion calculation processing on the fused feedback amount sequence and the motor drive value set of the current time period to obtain the motor drive value set of the next moment.

10. The microgravity simulation method according to claim 9, characterized in that: The expression of the feedback calculation process is: Among them, p i represents the i-th fusion feedback quantity in the fusion feedback quantity sequence; The expression of the feedback fusion calculation process is: Among them, f i (t) represents the driving value of the motor of the i-th bearing at the current time t, f i (t+1) represents the driving value of the motor of the i-th bearing at time t+1, the value of i is 1, 2, 3 or 4, and η is a preset proportional constant.

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