Space flexible truss vibration control experimental system based on liquid-electric hybrid actuator

Abstract

The application discloses a space flexible truss vibration control experimental system based on a liquid-electric hybrid actuator, comprising: a single machine performance test platform of the liquid-electric hybrid actuator, which is used for verifying the static output force characteristics, positioning characteristics and driving frequency response characteristics of the liquid-electric hybrid actuator under the open-loop no-load condition; a one-dimensional vibration isolation test platform of the liquid-electric hybrid actuator, which is used for verifying the active-passive integrated one-dimensional broadband vibration isolation effect of the liquid-electric hybrid actuator under the variable load condition; and a flexible truss vibration control ground test platform based on the liquid-electric hybrid actuator, which is used for measuring the influence law of the flexible truss dynamic response and controlling the output of the liquid-electric hybrid actuator. The application can reflect the influence law of the hinge nonlinearity and geometric nonlinearity on the flexible truss dynamic response on one hand, and can verify and compare the effectiveness and practicability of the online vibration active control algorithm of the flexible truss structure on the other hand.

Description

Technical Field

[0001] This invention relates to the field of vibration control of flexible space structures, and specifically to an experimental system for vibration control of a flexible space truss based on a liquid-electric hybrid actuator. Background Technology

[0002] Due to their large span, low stiffness, low fundamental frequency, and weak damping, space flexible trusses are highly susceptible to external disturbances and prone to vibrations that are difficult to dampen under the microgravity environment of space. Therefore, vibration control of space flexible trusses is essential. However, vibration control of space flexible trusses is a major challenge in the global aerospace field. This is mainly because these structures are not only large and complex systems, but also subject to constraints on the size, mass, power consumption, and installation of vibration control devices in aerospace applications. Furthermore, the special requirements of aerospace structures and the unique characteristics of the space environment make vibration control of space flexible truss structures a challenging engineering problem.

[0003] In next-generation spacecraft, as the span of flexible trusses continues to increase, the proportion of the truss's mass and moment of inertia in the overall spacecraft structure rises, leading to a strengthening coupling effect between the truss's elastic vibration and the motion of the spacecraft's main platform. Large articulated flexible trusses installed on spacecraft are typically connected by hinges, resulting in low-frequency, modal-dense, and nonlinear characteristics in flexible multibody structures under multi-source excitation in space. Furthermore, the complexity of flexible truss structures, including multibody structures, rigid-flexible coupling issues, and combined bending-torsional vibrations, contributes to high system dimensionality and challenges in controller design.

[0004] Furthermore, existing dynamics and control modeling and simulation results are insufficient to accurately reflect the influence of geometric nonlinearity, material nonlinearity, hinge friction, and collision on the dynamic response of complex truss systems. Therefore, it is urgent to investigate the influence mechanism of hinge nonlinearity, geometric and material nonlinearity on the dynamic response of flexible truss structures through experimental means, verify the effectiveness and practicality of online vibration strategies for flexible truss structures based on hydraulic-electric hybrid actuators, and provide theoretical guidance and technical support for the dynamic design and vibration control of my country's new generation of large-scale flexible space truss structures. Summary of the Invention

[0005] To address the aforementioned challenges, this invention proposes a spatial flexible truss vibration control experimental system based on a hydraulic-electric hybrid actuator. This invention is used to verify the static output force characteristics, positioning characteristics, and driving frequency response characteristics of the hydraulic-electric hybrid actuator under open-loop no-load conditions, providing technical support for subsequent broadband vibration isolation testing of the hydraulic-electric hybrid actuator.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solution:

[0007] An experimental system for vibration control of a spatial flexible truss based on a hydraulic-electric hybrid actuator includes: a single-unit performance testing platform for the hydraulic-electric hybrid actuator, used to verify the static output force characteristics, positioning characteristics, and driving frequency response characteristics of the hydraulic-electric hybrid actuator under open-loop no-load conditions; a one-dimensional vibration isolation testing platform for the hydraulic-electric hybrid actuator, used to verify the integrated active and passive one-dimensional broadband vibration isolation effect of the hydraulic-electric hybrid actuator under variable load conditions; and a ground-based experimental platform for vibration control of the flexible truss based on the hydraulic-electric hybrid actuator, used to measure the influence law of the dynamic response of the flexible truss and to control the output of the hydraulic-electric hybrid actuator.

[0008] Optionally, the single-unit performance testing platform for the hydraulic-electric hybrid actuator includes: a hydraulic-electric hybrid actuator 2, an optical air-bearing platform 6, a laser displacement sensor 9, a vise clamping device 3, a precision displacement adjustment platform 5, a host computer 7, a current source 1, a measurement and control system 8, a force sensor 4, and a signal generator 10.

[0009] The single-unit performance testing platform for the hydraulic-electric hybrid actuator, used to verify the static output force characteristics of the hydraulic-electric hybrid actuator, includes: the optical air-bearing platform 6, the current source 1, the hydraulic-electric hybrid actuator 2, the force sensor 4, and the precision displacement adjustment platform 5, which are respectively disposed on the optical air-bearing platform 6 and connected in sequence.

[0010] The measurement and control system 8 is connected to the hydraulic-electric hybrid actuator 2 and the force sensor 4 respectively;

[0011] The host computer 7 is connected to the measurement and control system 8.

[0012] The single-unit performance testing platform for the hydraulic-electric hybrid actuator, used to verify the positioning characteristics of the hydraulic-electric hybrid actuator, includes: an optical air-bearing platform 6, a current source 1, a hydraulic-electric hybrid actuator 2, and a laser displacement sensor 9, all respectively mounted on the optical air-bearing platform 6 and connected in sequence; a measurement and control system 8 connected to the hydraulic-electric hybrid actuator 2; and a host computer 7 connected to the measurement and control system 8.

[0013] The single-unit performance test platform for the hydraulic-electric hybrid actuator, used to verify the drive frequency response characteristics of the hydraulic-electric hybrid actuator, includes: an optical air-bearing platform 6, a current source 1, a hydraulic-electric hybrid actuator 2, and a laser displacement sensor 9, all respectively mounted on the optical air-bearing platform 6 and connected in sequence; a signal generator 10 connected to the current source 1; a measurement and control system 8 connected to the hydraulic-electric hybrid actuator 2; and a host computer 7 connected to the measurement and control system 8.

[0014] Optionally, when verifying the static output force characteristics of the hydraulic-electric hybrid actuator, the current source 1 is used to apply different DC currents to the hydraulic-electric hybrid actuator 2, and the force sensor 4 is used to measure the static output force at different positions of the output end of the hydraulic-electric hybrid actuator 2.

[0015] Optionally, when verifying the single-machine positioning characteristics of the hydraulic-electric hybrid actuator, the hydraulic-electric hybrid actuator 2 is loaded with sinusoidal alternating current, and the displacement response at the output end is measured by the laser displacement sensor 9 to obtain the maximum displacement output response capability.

[0016] Optionally, when verifying the drive frequency response characteristics of the hydraulic-electric hybrid actuator, the signal generator 10 performs frequency sweeping on the current source 1, and the laser displacement sensor 9 measures the drive frequency response of the output terminal of the hydraulic-electric hybrid actuator 2 in the low-frequency and mid-to-high-frequency ranges.

[0017] Optionally, the one-dimensional vibration isolation test platform for the hydraulic-electric hybrid actuator includes: a power amplifier 11, an electromagnetic exciter 12, a force sensor 4, a hydraulic-electric hybrid actuator 2, a load mass 14, and two laser displacement sensors 9 connected in sequence, one of which is connected to the hydraulic-electric hybrid actuator 2 and the other to the load mass 14; a measurement and control system 8, which is connected to the two laser displacement sensors 9 respectively; a current source 1, which is connected to the hydraulic-electric hybrid actuator 2 and the measurement and control system 8 respectively; a host computer 7, which is connected to the measurement and control system 8; a signal generator 10 connected to the power amplifier 11; and an elastic rope 13 for suspending the load mass 14 and the hydraulic-electric hybrid actuator 2 to simulate a weightless environment.

[0018] Optionally, the center of mass of the load mass 14 is located on the axis of the hydraulic-electric hybrid actuator 2; the two laser displacement sensors 9 respectively collect the interference displacement signal generated by the electromagnetic exciter 12 and the displacement response signal of the load mass 14; the signal generator 10 is used to control the electromagnetic exciter 12 to output a sweep frequency signal of 0.01~200Hz; the two laser displacement sensors 9 are also used to measure the input and output responses of the hydraulic-electric hybrid actuator 2; the measurement and control system 8 is used to input the signal picked up by the laser displacement sensors 9 and output the control signal obtained after the control strategy calculation by the host computer 7; the hydraulic-electric hybrid actuator 2 receives the control signal and executes it; based on the interference displacement signal and the displacement response signal, the displacement transmissibility of the one-dimensional vibration isolation test platform of the hydraulic-electric hybrid actuator is obtained, and the resonance frequency band of the one-dimensional vibration isolation test platform of the hydraulic-electric hybrid actuator is analyzed to verify the one-dimensional vibration isolation effect of the hydraulic-electric hybrid actuator 2.

[0019] Optionally, the one-dimensional vibration isolation test platform for the hydraulic-electric hybrid actuator is also used to test the vibration isolation effect of the hydraulic-electric hybrid actuator 2 under single-frequency excitation, including:

[0020] The electromagnetic exciter 12 is used for excitation, and the object of vibration isolation is the load mass 14.

[0021] By using two laser displacement sensors 9, the displacement response at both ends of the hydraulic-electric hybrid actuator 2 is measured, thereby obtaining the displacement transmissivity of the one-dimensional vibration isolation test platform of the hydraulic-electric hybrid actuator.

[0022] For single-frequency excitation, since each frequency has a corresponding displacement transmissibility, starting from 0.01Hz, the frequency is gradually increased according to the preset frequency interval to plot the frequency response curve between displacement transmissibility and frequency, thereby verifying the vibration isolation effect of the hydraulic-electric hybrid actuator 2.

[0023] Optionally, the flexible truss vibration control ground experimental platform based on a hydraulic-electric hybrid actuator includes: a crossbeam 15; an elastic rope 13; a flexible truss 18, which is suspended from the crossbeam 15 by the elastic rope 13 to simulate a microgravity environment in space; a hydraulic-electric hybrid actuator 2, which is disposed at the end of the flexible truss 18; a force sensor 4, which is disposed at the end of the hydraulic-electric hybrid actuator 2; an electromagnetic exciter 12, which is connected to the root of the flexible truss 18 to simulate low-frequency and mid-to-high-frequency interference; and a pendulum impact device 17, which acts on the middle of the flexible truss 18 to simulate impact. Interference; a three-dimensional dynamic non-contact laser vibration meter 16, located at the end of the flexible truss 18, is used to measure the bending vibration response at the end of the truss, perform spectrum analysis, and determine the resonant frequency of the ground experimental platform for vibration control of the flexible truss based on the hydraulic-electric hybrid actuator; a current source 1, a measurement and control system 8, and a host computer 7 are connected in sequence, the current source 1 is also connected to the hydraulic-electric hybrid actuator 2; the measurement and control system 8 is also connected to the force sensor 4; a signal generator 10 and a power amplifier 11 are connected to the signal generator 10; the power amplifier 11 is connected to the electromagnetic exciter 12.

[0024] Optionally, the three-dimensional dynamic non-contact laser vibrometer 16 is used to measure the bending vibration at the end of the flexible truss 18; the single pendulum impact device 17 acts on the middle of the flexible truss 18 to simulate repeatable impact interference; the force sensor 4 collects signals under impact interference and, through the host computer 7, acts on the analog output card of the measurement and control system 8 to control the output of the hydraulic-electric hybrid actuator 2; the electromagnetic exciter 12 acts on the root of the flexible truss 18 to simulate single-frequency excitation interference; and the hydraulic-electric hybrid actuator 2 is controlled based on the signals collected by the force sensor 4 to verify the vibration control effect of the hydraulic-electric hybrid actuator 2 under wideband excitation.

[0025] This invention has one of the following technical effects:

[0026] The single-unit performance testing platform for the hydraulic-electric hybrid actuator provided by this invention has multi-functional characteristics and can be used to verify the static output force characteristics, positioning characteristics, and driving frequency response characteristics of the hydraulic-electric hybrid actuator under open-loop no-load conditions, providing technical support for subsequent broadband vibration isolation testing of the hydraulic-electric hybrid actuator.

[0027] The one-dimensional vibration isolation test platform for the hydraulic-electric hybrid actuator provided by this invention is easy to disassemble and install under load mass, and can verify the active and passive integrated one-dimensional vibration isolation effect of the hydraulic-electric hybrid actuator under variable load, which can save experimental time and improve experimental efficiency.

[0028] This invention provides a ground-based experimental platform for vibration control of flexible trusses based on a hydraulic-electric hybrid actuator. By utilizing a suspension method to balance the gravity of the flexible truss, it simulates the actual microgravity environment in space, resulting in more reliable experimental results. This ground-based experimental system can realistically reflect the influence of hinge nonlinearity and geometric nonlinearity on the dynamic response of flexible trusses. Furthermore, it can verify and compare the effectiveness and practicality of online active vibration control algorithms for flexible truss structures, thereby revealing the integrated active and passive broadband vibration isolation mechanism of space flexible trusses under multi-source excitation. This technical method is simple in concept and has advantages such as strong systematicity, ease of promotion, and low cost. Attached Figure Description

[0029] Figure 1a A schematic diagram of a single-machine performance testing platform for testing the static output force characteristics of a hydraulic-electric hybrid actuator, provided in an embodiment of the present invention;

[0030] Figure 1b This is a schematic diagram of a single-machine performance testing platform for testing the positioning characteristics of a hydraulic-electric hybrid actuator, provided in an embodiment of the present invention.

[0031] Figure 1c This is a schematic diagram of a single-machine performance testing platform for testing the drive frequency response characteristics of a hydraulic-electric hybrid actuator, provided in an embodiment of the present invention.

[0032] Figure 2 This is a schematic diagram of a one-dimensional vibration isolation test platform for a hydraulic-electric hybrid actuator provided in an embodiment of the present invention;

[0033] Figure 3 This is a schematic diagram of a ground experimental platform for flexible truss vibration control based on a hydraulic-electric hybrid actuator, provided in an embodiment of the present invention.

[0034] Explanation of reference numerals in the attached diagram: 1-NF BP4610 current source, 2-hydraulic-electric hybrid actuator, 3-viggle clamping device, 4-Kistler force sensor, 5-precision displacement adjustment platform, 6-optical air-bearing platform, 7-PC / LabVIEW host computer, 8-NI Compact-RIO measurement and control system, 9-Keyence laser displacement sensor, 10-NF signal generator, 11-VSA power amplifier, 12-LT-50 electromagnetic vibrator, 13-elastic rope, 14-load mass, 15-crossbeam, 16-Polytec three-dimensional dynamic non-contact laser vibrometer, 17-single pendulum impact device, 18-flexible truss. Detailed Implementation

[0035] The following detailed description, in conjunction with the accompanying drawings and specific embodiments, provides a method for autonomous acquisition and control of the solar vector across the entire sky using only a limited field-of-view analog solar sensor, as proposed in this invention. The advantages and features of this invention will become clearer from the following description. It should be noted that the accompanying drawings are in a very simplified form and use non-precise scales, used only to facilitate and clarify the illustration of the embodiments of this invention. Please refer to the accompanying drawings for a clearer understanding of the objectives, features, and advantages of this invention. It should be understood that the structures, scales, sizes, etc., depicted in the accompanying drawings are only for illustrative purposes and to aid those skilled in the art, and are not intended to limit the implementation conditions of this invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in scale, or adjustments to the size, without affecting the effects and objectives achieved by this invention, should still fall within the scope of the technical content disclosed in this invention.

[0036] This embodiment provides a space flexible truss vibration control experimental system based on a hydraulic-electric hybrid actuator, comprising: a single-machine performance testing platform for the hydraulic-electric hybrid actuator, used for conducting static force tests, positioning tests, and drive frequency response tests of the single-machine hydraulic-electric hybrid actuator under no-load conditions, thereby verifying the static output force characteristics, positioning characteristics, and drive frequency response characteristics of the hydraulic-electric hybrid actuator; a one-dimensional vibration isolation testing platform for the hydraulic-electric hybrid actuator, used to verify the active-passive integrated one-dimensional broadband vibration isolation effect of the hydraulic-electric hybrid actuator under variable load conditions; and a ground-based experimental platform for flexible truss vibration control based on the hydraulic-electric hybrid actuator, used to measure the influence law of the dynamic response of the flexible truss and control the output of the hydraulic-electric hybrid actuator.

[0037] Therefore, this embodiment provides a space flexible truss vibration control experimental system based on a hydraulic-electric hybrid actuator. It mainly includes: a single-machine performance testing platform for the hydraulic-electric hybrid actuator, used to verify the static output force characteristics, positioning characteristics, and driving frequency response characteristics of the hydraulic-electric hybrid actuator under open-loop no-load conditions; a one-dimensional vibration isolation testing platform for the hydraulic-electric hybrid actuator, used to verify the integrated active-passive one-dimensional broadband vibration isolation effect of the hydraulic-electric hybrid actuator under variable loads; and a ground-based experimental platform for flexible truss vibration control based on the hydraulic-electric hybrid actuator, which uses a suspension method to simulate a microgravity environment in space. This platform not only realistically reflects the influence of hinge nonlinearity and geometric nonlinearity on the dynamic response of the flexible truss, but also verifies the effectiveness, feasibility, and practicality of the integrated active-passive vibration control strategy for the flexible truss structure. This invention has a simple technical concept and advantages such as strong systematicity, ease of promotion, and low cost.

[0038] Specifically, the single-machine performance testing platform for the hydraulic-electric hybrid actuator in this embodiment includes: a hydraulic-electric hybrid actuator 2, an optical air-bearing platform 6, a laser displacement sensor 9, a vise clamping device 3, a precision displacement adjustment platform 5, a host computer 7, a current source 1, a measurement and control system 8, a force sensor 4, and a signal generator 10.

[0039] During the single-machine test of the hydraulic-electric hybrid actuator 2, the outer shell of the hydraulic-electric hybrid actuator 2 is clamped and fixed by the vise clamping device 3, with one end fixed and the other end free, and the output force and displacement response of its free end are studied.

[0040] like Figure 1a As shown, the single-unit performance testing platform for the hydraulic-electric hybrid actuator, used to verify the static output force characteristics of the hydraulic-electric hybrid actuator, includes: an optical air-bearing platform 6, a current source 1 respectively disposed on the optical air-bearing platform 6 and connected in sequence, the hydraulic-electric hybrid actuator 2, the force sensor 4, and the precision displacement adjustment platform 5. The measurement and control system 8 is connected to the hydraulic-electric hybrid actuator 2 and the force sensor 4 respectively; the host computer 7 is connected to the measurement and control system 8.

[0041] Specifically, the output end of the hydraulic-electric hybrid actuator 2 is connected to one end of the force sensor 4, and the other end of the force sensor 4 is connected to the precision displacement adjustment platform 5. The base of the precision displacement adjustment platform 5 is fixed on the optical air-bearing platform 6.

[0042] The measurement and control system 8 is equipped with a four-channel analog output card that outputs control signals. The current source 1 controls the current signal of the hydraulic-electric hybrid actuator 2 according to the received control signals. The measurement and control system 8 is equipped with a four-channel data acquisition card that acquires force signals.

[0043] Different DC currents (0-1A, measured every 0.1A) are applied to the hydraulic-electric hybrid actuator 2 through current source 1, and then input to the input terminal of the hydraulic-electric hybrid actuator 2; the static output force (force signal) at different positions of the output terminal (-3 to 3mm, measured every 0.1mm) is measured by force sensor 4.

[0044] The host computer 7 is used to receive the force signal collected by the measurement and control system 8. The force signal is a time-domain signal within a certain time range, that is, it will have some random fluctuations on the basis of static force. Then, the collected force signal is averaged to generate an equivalent static force, and the generated static force signal is output to the host computer 7 through the measurement and control system 8.

[0045] like Figure 1b As shown, the single-unit performance testing platform for the hydraulic-electric hybrid actuator, used to verify the positioning characteristics of the hydraulic-electric hybrid actuator, includes: an optical air-bearing platform 6, a current source 1, a hydraulic-electric hybrid actuator 2, and a laser displacement sensor 9, all respectively mounted on the optical air-bearing platform 6 and connected in sequence; a measurement and control system 8 connected to the hydraulic-electric hybrid actuator 2; and a host computer 7 connected to the measurement and control system 8.

[0046] When verifying the single-machine positioning characteristics of the hydraulic-electric hybrid actuator, the hydraulic-electric hybrid actuator 2 is loaded with sinusoidal alternating current, and the displacement response at the output end is measured by the laser displacement sensor 9 to obtain the maximum displacement output response capability.

[0047] Specifically, a standard 0-1Hz sinusoidal current signal with a peak value of 1A is applied to the input port of the liquid-electric hybrid actuator 2 through the current source 1, and the laser displacement sensor 9 collects the output displacement signal.

[0048] The measurement and control system 8 transmits the received displacement signal to the host computer 7, and the host computer 7 analyzes the maximum output response capability of the hybrid actuator 2 based on the displacement signal.

[0049] like Figure 1c As shown, the single-unit performance test platform for the hydraulic-electric hybrid actuator, used to verify the drive frequency response characteristics of the hydraulic-electric hybrid actuator, includes: an optical air-bearing platform 6, a current source 1, a hydraulic-electric hybrid actuator 2, and a laser displacement sensor 9, all respectively mounted on the optical air-bearing platform 6 and connected in sequence; a signal generator 10 connected to the current source 1; a measurement and control system 8 connected to the hydraulic-electric hybrid actuator 2; and a host computer 7 connected to the measurement and control system 8.

[0050] When verifying the drive frequency response characteristics of the hydraulic-electric hybrid actuator

[0051] The signal generator 10 is applied to the current source 1 to sweep the frequency (0.01-200Hz) of the current input of the hydraulic-electric hybrid actuator 2, and the displacement response capability of the hydraulic-electric hybrid actuator 2 under different excitation frequencies is tested. The drive frequency response of the output terminal of the hydraulic-electric hybrid actuator 2 in the low-frequency and mid-to-high-frequency ranges is measured by the laser displacement sensor 9.

[0052] Specifically, during the unloaded driving frequency response test of the hydraulic-electric hybrid actuator 2, the signal generator 10 is applied to the current source 1 to sweep the frequency of the current input of the hydraulic-electric hybrid actuator 2, and its displacement response capability under different excitation frequencies is tested. The hydraulic-electric hybrid actuator 2 is loaded with a current signal with a peak value of 1A and an excitation frequency ranging from 0.01 to 200Hz. Then, the output response of the free end of the hydraulic-electric hybrid actuator 2 in the full frequency band (0.01 to 200Hz) is measured by the laser displacement sensor 9, thereby obtaining the driving frequency response of the hydraulic-electric hybrid actuator 2 in the low frequency band (0.01 to 10Hz) and the mid-to-high frequency band (10 to 200Hz).

[0053] The measurement and control system 8 transmits the received current signal with a peak load of 1A and an excitation frequency varying from 0.01 to 200Hz, and the output response of the free end of the hydro-hydraulic actuator 2 across the entire frequency band (0.01 to 200Hz) to the host computer 7. The host computer 7 analyzes the driving frequency response of the hybrid actuator 2 in the low-frequency band (0.01 to 10Hz) and the mid-to-high frequency band (10 to 200Hz) based on the received information.

[0054] like Figure 2 As shown, the one-dimensional vibration isolation test platform for the hydraulic-electric hybrid actuator includes: a power amplifier 11, an electromagnetic exciter 12, a force sensor 4, a hydraulic-electric hybrid actuator 2, a load mass 14, and two laser displacement sensors 9 connected in sequence, one of which is connected to the hydraulic-electric hybrid actuator 2 and the other to the load mass 14; a measurement and control system 8, which is connected to the two laser displacement sensors 9 respectively; a current source 1, which is connected to the hydraulic-electric hybrid actuator 2 and the measurement and control system 8 respectively; a host computer 7, which is connected to the measurement and control system 8; a signal generator 10, which is connected to the power amplifier 11; and an elastic rope 13, used to suspend the load mass 14 and the hydraulic-electric hybrid actuator 2 to simulate a weightless environment.

[0055] The center of mass of the load mass 14 is located on the axis of the hydraulic-electric hybrid actuator 2;

[0056] Two laser displacement sensors 9 respectively acquire the interference displacement signal generated by the electromagnetic vibrator 12 and the displacement response signal of the load mass 14; the signal generator 10 is used to control the electromagnetic vibrator 12 to output a sweep frequency signal of 0.01~200Hz; the two laser displacement sensors 9 are also used to measure the input and output responses of the hydraulic-electric hybrid actuator 2; the measurement and control system 8 is used to input the signal picked up by the laser displacement sensors 9 and output the control signal obtained after the control strategy calculation by the host computer 7; the hydraulic-electric hybrid actuator 2 receives the control signal and executes it; based on the interference displacement signal and the displacement response signal, the displacement transmissibility of the one-dimensional vibration isolation test platform of the hydraulic-electric hybrid actuator is obtained, and the resonant frequency band of the one-dimensional vibration isolation test platform of the hydraulic-electric hybrid actuator is analyzed to verify the one-dimensional vibration isolation effect of the hydraulic-electric hybrid actuator 2.

[0057] That is, the electromagnetic vibrator 12 is frequency swept, and two laser displacement sensors 9 are used to measure the vibration displacement response of the foundation input and the load mass 14, respectively. Based on the displacement response of the foundation input and the load mass 14, the current source 1 is controlled to control the output of the hydraulic-electric hybrid actuator, thereby verifying the active and passive integrated one-dimensional vibration isolation effect of the hydraulic-electric hybrid actuator under variable load.

[0058] The steps for verifying the integrated active and passive vibration isolation performance of the hydraulic-electric hybrid actuator using the one-dimensional vibration isolation test platform include the following:

[0059] A. To simulate a weightless environment, the hydraulic-electric hybrid actuator 2 and the load mass 14 are suspended. A force sensor 4 is attached to the output end of the electromagnetic exciter 12, and the two ends of the hydraulic-electric hybrid actuator 2 are in contact with the force sensor 4 and the end of the load mass 14, respectively.

[0060] B. Adjust the length and position of the elastic rope 13 so that the center of mass of the load mass 14 is located on the axis of the hydraulic-electric hybrid actuator 2, while the weight of the load mass 14 is adjustable.

[0061] C. Two laser displacement sensors 9 are used to collect the interference displacement signal generated by the electromagnetic vibrator 12 and the displacement response signal of the load mass 14, respectively.

[0062] D. The electromagnetic exciter 12 is controlled by the signal generator 10 to output a sweep frequency signal of 0.01 to 200 Hz, and the response of the input and output terminals of the hydraulic-electric hybrid actuator 2 is measured by the laser displacement sensor 9.

[0063] E. The received interference displacement signal and displacement response signal are transmitted to the host computer 7 using the measurement and control system 8. The host computer 7 calculates the control signal based on the received interference displacement signal and displacement response signal using its own control strategy and outputs it. The control signal is output to the current source 1 to control the output of the current source 1. The control signal is then applied to the hydraulic-electric hybrid actuator 2 through the current source 1.

[0064] F. Based on the interference displacement signal and the displacement response signal of the load mass 14, the displacement transmissivity of the one-dimensional vibration isolation test platform of the hydraulic-electric hybrid actuator is obtained. At the same time, the resonance frequency band of the one-dimensional vibration isolation test platform of the hydraulic-electric hybrid actuator is analyzed to verify the one-dimensional vibration isolation effect of the hydraulic-electric hybrid actuator 2.

[0065] G. In this embodiment, the one-dimensional vibration isolation test platform of the hydraulic-electric hybrid actuator is also used to excite the actuator near the resonant frequency and test the vibration isolation effect of the hydraulic-electric hybrid actuator 2 under single-frequency excitation.

[0066] Including the specific process:

[0067] An electromagnetic exciter 12 is used for excitation, and the vibration isolation object is the load mass 14. Two laser displacement sensors 9 are used to measure the displacement response at both ends of the hydraulic-electric hybrid actuator 2, thereby obtaining the displacement transmissivity of the one-dimensional vibration isolation test platform of the hydraulic-electric hybrid actuator. For single-frequency excitation, on the one hand, since each frequency has a corresponding displacement transmissivity, starting from 0.01Hz and gradually increasing in increments of 0.1Hz, a frequency response curve between displacement transmissivity (vertical axis) and frequency (horizontal axis) can be plotted, thus verifying the vibration isolation effect of the hydraulic-electric hybrid actuator 2. On the other hand, since the frequency range of 0.01 to 200Hz completely covers the natural frequency of the one-dimensional vibration isolation test platform of the hydraulic-electric hybrid actuator, starting from 0.01Hz and gradually increasing in increments of 0.1Hz up to 200Hz, the resonant frequency of the one-dimensional vibration isolation test platform of the hydraulic-electric hybrid actuator can be found.

[0068] like Figure 3As shown, the flexible truss vibration control ground experimental platform based on a hydraulic-electric hybrid actuator includes: a crossbeam 15; an elastic rope 13; a flexible truss 18, which is suspended from the crossbeam 15 by the elastic rope 13 to simulate a microgravity environment (specifically, the flexible truss 18 is cantilevered, and its extended portion is suspended from the crossbeam 15 by the elastic rope 13 to simulate a microgravity environment); a hydraulic-electric hybrid actuator 2, which is disposed at the end of the flexible truss 18; a force sensor 4, which is disposed at the end of the hydraulic-electric hybrid actuator 2; and an electromagnetic exciter 12, which is connected to the root of the flexible truss 18 to simulate low-frequency and mid-to-high-frequency interference; and a single... A pendulum impact device 17 acts on the middle of the flexible truss 18 to simulate impact interference; a three-dimensional dynamic non-contact laser vibration meter 16 is located at the end of the flexible truss 18 to measure the bending vibration response at the end of the truss, perform spectrum analysis, and determine the resonant frequency of the ground experimental platform for vibration control of the flexible truss based on the hydraulic-electric hybrid actuator; a current source 1, a measurement and control system 8, and a host computer 7 are connected in sequence, with the current source 1 also connected to the hydraulic-electric hybrid actuator 2; the measurement and control system 8 is also connected to the force sensor 4; a signal generator 10 and a power amplifier 11 are connected to the signal generator 10; the power amplifier 11 is connected to the electromagnetic exciter 12.

[0069] Please continue to refer to this. Figure 3 As shown, the three-dimensional dynamic non-contact laser vibration meter 16 is used to measure the bending vibration at the end of the flexible truss 18; the single pendulum impact device 17 acts on the middle part of the flexible truss 18 to simulate repeatable impact interference.

[0070] Specifically, under impact interference, a simple pendulum is released freely from a certain height, repeatedly impacting the middle of the flexible truss 18 system. Then, under the active control of the hydraulic-electric hybrid actuator 2, the structure stabilizes at the equilibrium position. First, a non-contact laser vibration meter 16 measures the bending vibration at the end of the flexible truss 18. At this time, the force sensor 4, based on the signal collected under impact interference, controls the output of the hydraulic-electric hybrid actuator 2 through the analog output card of the host computer 7 via the host computer 7.

[0071] The electromagnetic exciter 12 acts on the root of the flexible truss 18, first performing frequency sweep, and then simulating single-frequency excitation interference.

[0072] Specifically, an electromagnetic exciter 12 is applied to the root of the flexible truss. First, the electromagnetic exciter 12 is set to sweep a frequency from 0.01 to 200 Hz. A non-contact laser vibrometer 16 is used to measure the bending vibration response at the end of the flexible truss 18, and spectral analysis is performed to determine the resonant frequency of the ground experimental platform for flexible truss vibration control based on the hydraulic-electric hybrid actuator. Based on the signal collected by the force sensor 4, the hydraulic-electric hybrid actuator 2 is controlled through the current source 1 to suppress the vibration generated by the flexible truss; the vibration control effect of the hydraulic-electric hybrid actuator 2 under broadband excitation is verified. Then, the active control effect of low-frequency large-amplitude vibration and the passive vibration control effect of the ground experimental platform for flexible truss vibration control based on the hydraulic-electric hybrid actuator are studied near the resonant frequency under single-frequency excitation.

[0073] The measurement and control system 8 is used to control the current output of the current source 1 and the force sensing signal acquisition of the force sensor 4; the host computer transmits data to the measurement and control system 8 through the host computer 7, and receives control commands from the host computer through the four-channel analog output card configured in the measurement and control system 8; the current source 1 drives the hydraulic-electric hybrid actuator 2 according to the received control commands; the measurement and control system 8 uses the configured four-channel data acquisition card to acquire the output signal of the force sensor 4; at the same time, the monitoring interface of the host computer 7 can realize real-time monitoring, adjustment and recording of state variables.

[0074] In summary, by constructing the aforementioned ground-based experimental system for vibration control of flexible trusses based on a hydraulic-electric hybrid actuator, we studied the online active vibration control strategy of the root hydraulic-electric hybrid actuator and revealed the active-passive integrated broadband vibration isolation mechanism of spatial flexible trusses under multi-source excitation in space.

[0075] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0076] It should be noted that the apparatus and methods disclosed in the embodiments herein can also be implemented in other ways. The apparatus embodiments described above are merely illustrative; for example, the flowcharts and block diagrams in the accompanying drawings show the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments herein. In this regard, each block in a flowchart or block diagram may represent a module, program, or part of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system to perform the specified function or action, or can be implemented using a combination of dedicated hardware and computer instructions.

[0077] In addition, the functional modules in the various embodiments of this article can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0078] Although the present invention has been described in detail through the preferred embodiments above, it should be understood that the above description should not be considered as a limitation of the present invention. Various modifications and substitutions to the present invention will be apparent to those skilled in the art after reading the above description. Therefore, the scope of protection of the present invention should be defined by the appended claims.

Claims

1. A space flexible truss vibration control experimental system based on a liquid-electric hybrid actuator, characterized in that, It comprises: a single machine performance test platform of a hydraulic-electric hybrid actuator, used for verifying the static output force characteristics, positioning characteristics and driving frequency response characteristics of the hydraulic-electric hybrid actuator under open-loop no-load conditions; a one-dimensional vibration isolation test platform of the hydraulic-electric hybrid actuator, used for verifying the one-dimensional broadband vibration isolation effect of the hydraulic-electric hybrid actuator under variable load conditions; and a flexible truss vibration control ground test platform based on the hydraulic-electric hybrid actuator, used for measuring the influence law of the dynamic response of the flexible truss and controlling the output of the hydraulic-electric hybrid actuator. The flexible truss vibration control ground test platform based on the hydraulic-electric hybrid actuator comprises: a crossbeam (15); elastic ropes (13); a flexible truss (18) suspended on the crossbeam (15) through the elastic ropes (13) to simulate a space microgravity environment; a hydraulic-electric hybrid actuator (2) arranged on an end of the flexible truss (18); a force sensor (4) arranged at an end of the hydraulic-electric hybrid actuator (2); an electromagnetic exciter (12) connected with a root of the flexible truss (18) to simulate low-frequency and medium-high-frequency interference; a single-pendulum impact device (17) acting on a middle part of the flexible truss (18) to simulate impact interference; a three-dimensional dynamic non-contact laser vibration meter (16) located at an end of the flexible truss (18) to measure the bending vibration response of the end of the flexible truss, perform frequency spectrum analysis, and determine the resonance frequency of the flexible truss vibration control ground test platform based on the hydraulic-electric hybrid actuator; a current source (1), a measurement and control system (8) and an upper computer (7) connected in sequence, the current source (1) is further connected with the hydraulic-electric hybrid actuator (2); the measurement and control system (8) is further connected with the force sensor (4); a signal generator (10), a power amplifier (11) connected with the signal generator (10); the power amplifier (11) is connected with the electromagnetic exciter (12); the three-dimensional dynamic non-contact laser vibration meter (16) is used to measure the bending vibration of the end of the flexible truss (18); the single-pendulum impact device (17) acts on the middle part of the flexible truss (18) to simulate repeatable impact interference; the force sensor (4) collects signals under impact interference, and controls the output of the hydraulic-electric hybrid actuator (2) through the analog output card of the measurement and control system (8) acted on by the upper computer (7); the electromagnetic exciter (12) acts on the root of the flexible truss (18) to simulate single-frequency excitation interference; the hydraulic-electric hybrid actuator (2) is controlled and outputted according to the signals collected by the force sensor (4) to verify the vibration control effect of the hydraulic-electric hybrid actuator (2) under broadband excitation.

2. The space flexible truss vibration control test system based on the hydraulic-electric hybrid actuator according to claim 1, characterized in that, The single-machine performance test platform of the electro-hydraulic hybrid actuator is used for verifying the static output force characteristics of the electro-hydraulic hybrid actuator, and comprises an optical air floating platform (6), a current source (1) arranged on the optical air floating platform (6) and connected in sequence, an electro-hydraulic hybrid actuator (2), a force sensor (4) and a precise displacement adjustment platform (5); A measurement and control system (8) is connected with the electro-hydraulic hybrid actuator (2) and the force sensor (4); A host computer (7) is connected with the measurement and control system (8); The single-machine performance test platform of the electro-hydraulic hybrid actuator is used for verifying the positioning characteristics of the electro-hydraulic hybrid actuator, and comprises an optical air floating platform (6), the current source (1), the electro-hydraulic hybrid actuator (2) and a laser displacement sensor (9) arranged on the optical air floating platform (6) and connected in sequence; The measurement and control system (8) is connected with the electro-hydraulic hybrid actuator (2); The host computer (7) is connected with the measurement and control system (8); The single-machine performance test platform of the electro-hydraulic hybrid actuator is used for verifying the driving frequency response characteristics of the electro-hydraulic hybrid actuator, and comprises an optical air floating platform (6), the current source (1), the electro-hydraulic hybrid actuator (2) and the laser displacement sensor (9) arranged on the optical air floating platform (6) and connected in sequence; A signal generator (10) is connected with the current source (1); The measurement and control system (8) is connected with the electro-hydraulic hybrid actuator (2); The host computer (7) is connected with the measurement and control system (8).

3. The space flexible truss vibration control experimental system based on the electro-hydraulic hybrid actuator according to claim 2, wherein when verifying the static output force characteristics of the electro-hydraulic hybrid actuator, the current source (1) is used for loading different direct currents to the electro-hydraulic hybrid actuator (2) respectively, and the force sensor (4) is used for measuring the static output force at different positions of the output end of the electro-hydraulic hybrid actuator (2).

4. The space flexible truss vibration control experimental system based on the electro-hydraulic hybrid actuator according to claim 2, wherein when verifying the single-machine positioning characteristics of the electro-hydraulic hybrid actuator, the electro-hydraulic hybrid actuator (2) is loaded with sinusoidal alternating current, and the laser displacement sensor (9) is used for measuring the displacement response of the output end to obtain the maximum displacement output response capability.

5. The space flexible truss vibration control experimental system based on the electro-hydraulic hybrid actuator according to claim 2, wherein when verifying the driving frequency response characteristics of the electro-hydraulic hybrid actuator, the signal generator (10) is used for sweeping the current source (1), and the laser displacement sensor (9) is used for measuring the driving frequency response of the output end of the electro-hydraulic hybrid actuator (2) in the low frequency band and the medium-high frequency band.

6. The space flexible truss vibration control experimental system based on the electro-hydraulic hybrid actuator according to claim 1, wherein the one-dimensional vibration isolation test platform of the electro-hydraulic hybrid actuator comprises a power amplifier (11), an electromagnetic exciter (12), a force sensor (4), an electro-hydraulic hybrid actuator (2) and a load mass (14) connected in sequence. ​ ​ ​ ​ ​ ​ ​ two laser displacement sensors (9), one of which is connected to the electro-hydraulic hybrid actuator (2), and the other is connected to the load mass (14); a measurement and control system (8) connected to the two laser displacement sensors (9); a current source (1) connected to the electro-hydraulic hybrid actuator (2) and the measurement and control system (8); a host computer (7) connected to the measurement and control system (8); a signal generator (10) connected to the power amplifier (11); a flexible rope (13) used to suspend the load mass (14) and the electro-hydraulic hybrid actuator (2) to simulate a weightless environment.

7. The space flexible truss vibration control experimental system based on the electro-hydraulic hybrid actuator according to claim 6, wherein the center of mass of the load mass (14) is located on the axis of the electro-hydraulic hybrid actuator (2); the two laser displacement sensors (9) respectively collect the interference displacement signals generated by the electromagnetic exciter (12) and the displacement response signals of the load mass (14); the signal generator (10) is used to control the electromagnetic exciter (12) to output a sweep signal of 0.01-200 Hz; the two laser displacement sensors (9) are also used to measure the input and output responses of the electro-hydraulic hybrid actuator (2); the measurement and control system (8) is used to input the signals picked up by the laser displacement sensors (9) and output the control signals obtained after the control strategy of the host computer (7) is calculated; the electro-hydraulic hybrid actuator (2) receives the control signals and executes them; based on the interference displacement signals and the displacement response signals, the displacement transmissibility of the one-dimensional vibration isolation test platform of the electro-hydraulic hybrid actuator is obtained, and the resonance frequency band of the one-dimensional vibration isolation test platform of the electro-hydraulic hybrid actuator is analyzed to verify the one-dimensional vibration isolation effect of the electro-hydraulic hybrid actuator (2).

8. The space flexible truss vibration control experimental system based on the electro-hydraulic hybrid actuation according to claim 6, wherein the one-dimensional vibration isolation test platform of the electro-hydraulic hybrid actuator is also used to test the vibration isolation effect of the electro-hydraulic hybrid actuator (2) under single-frequency excitation, including: using the electromagnetic exciter (12) to excite, and the load mass (14) is the vibration isolation object; measuring the displacement responses at both ends of the electro-hydraulic hybrid actuator (2) through the two laser displacement sensors (9), and then obtaining the displacement transmissibility of the one-dimensional vibration isolation test platform of the electro-hydraulic actuator; for single-frequency excitation, since each frequency has a corresponding displacement transmissibility, starting from 0.01 Hz, the frequency is gradually increased according to the preset frequency interval, and the frequency response curve between the displacement transmissibility and the frequency is drawn, and then the vibration isolation effect of the electro-hydraulic hybrid actuator (2) is verified.

9. The space flexible truss vibration control experimental system based on the electro-hydraulic hybrid actuating according to claim 1, wherein the three-dimensional dynamic non-contact laser vibration meter (16) is used to measure the bending vibration at the end of the flexible truss (18). The single-pendulum impact device (17) acts on the middle part of the flexible truss (18) to simulate a repeatable impact disturbance; The force sensor (4) collects signals under impact disturbance, and the upper computer (7) acts on the analog output card of the measurement and control system (8) to control the output of the hydroelectric hybrid actuator (2); The electromagnetic exciter (12) acts on the root of the flexible truss (18) to simulate a single-frequency excitation disturbance; According to the signals collected by the force sensor (4), the hydroelectric hybrid actuator (2) is controlled to output, and the vibration control effect of the hydroelectric hybrid actuator (2) under wideband excitation is verified.

Images