A device and method for simulated microgravity test based on follow-up compensation of air pressure feedback

Abstract

The invention relates to a device and method for simulating microgravity test based on follow-up compensation of air pressure feedback, which belongs to the technical field of ground-based simulated microgravity test. The operating table is installed at the lower part of the gantry, the controller and the stepper motor are installed on the operating table, the bidirectional self-locking winch is fixedly installed on the output shaft of the stepper motor, the top of the gantry is fixedly connected to the wheel axles of the two pulleys, the central axis of the two pulleys is parallel to the central axis of the bidirectional self-locking winch, one end of the wire rope is connected to the upper end of the inflatable structure, and the other end is fixedly wound around the two pulleys and then wound on the bidirectional self-locking winch, the thin film silicon pressure sensor is fixed on the inflatable structure, and the probe of the thin film silicon pressure sensor is sealed and fixed inside the inflatable structure, the thin film silicon pressure sensor, the laser displacement sensor and the stepper motor are all connected to the controller signal, the controller is electrically connected to the power supply, the servo inflation system is connected to the inflatable structure through the inflation pipeline, and the laser displacement sensor is installed on the top of the gantry. The present invention is used for simulating microgravity test.

Description

Technical Field

[0001] The invention belongs to the technical field of ground simulated microgravity experiments, and in particular relates to a follow-up compensation simulated microgravity experiment device and method based on air pressure feedback. Background Art

[0002] Inflatable structures have the advantages of light weight, flexible foldability, and small launch volume, and have good application prospects in the construction of space stations and planetary bases, such as inflatable cabins, inflatable deployable antennas, inflatable deployable solar panels, etc. The ground-based simulated microgravity experiment and test of space inflatable structures is the key to the technical research and on-orbit application of inflatable structures.

[0003] At present, there are two main methods for ground-based simulated microgravity test technology: direct and indirect. Direct simulated microgravity test technology mainly includes two forms: unsupported free fall and parabolic flight. The unsupported free fall technology drops the specimen from a high tower, old mine shaft, etc., and uses the principle of free fall to simulate the microgravity environment. This method is suitable for specimens with smaller volumes. Parabolic flight technology is achieved through weightless aircraft. When a weightless aircraft performs a parabolic flight relative to the center of the earth, a microgravity environment can be simulated inside the aircraft. The direct simulated microgravity test method simulates the weightlessness effect for a short time, is difficult to apply to larger specimens, and is more expensive.

[0004] When conducting ground-based simulated microgravity tests on astronauts and large test pieces, indirect simulated microgravity test methods are currently mostly used, mainly including immersion, air flotation, bed rest, suspension, etc., which are achieved through neutral buoyancy water tanks, air flotation test devices, bed rest laboratories, cable suspension racks and other facilities. Neutral buoyancy simulation technology uses the buoyancy of water tanks to achieve astronaut training and spacecraft hardware testing, rendezvous and docking exercises. Air flotation simulated microgravity technology uses air flotation bearings, air flotation platforms and other devices, mainly used to simulate autonomous flight of spacecraft. Bed rest laboratories are mainly used for astronaut training and physiological research in microgravity environments. Suspension simulated microgravity technology mainly establishes a suspension system through rope mechanisms and pulley groups, which is mainly divided into two methods: active gravity compensation and passive gravity compensation. Active gravity compensation uses a controllable motor to adjust the rope tension, while passive gravity compensation uses counterweights to inefficiently force gravity, such as weights, water, sand, etc. Suspension simulated microgravity technology is mostly used to simulate weightlessness in large spacecraft equipment. Its suspension system has various forms. It is usually necessary to design the suspension system based on specific objects and test requirements, taking into account factors such as structural bearing capacity and stability. However, indirect simulated microgravity tests have problems such as high test difficulty, high cost, and long cycle. In addition, it is difficult to achieve real-time and accurate test specimen gravity compensation feedback during the simulated microgravity environment. In addition, in ground simulated microgravity tests, the type of specimen is significantly restricted by the test method. For example, the neutral buoyancy tank uses underwater simulated microgravity environment, which has great restrictions on test samples and prototypes containing fabrics, metals, etc.

[0005] The space inflatable structure is a new type of large-scale deployable space structure. Currently, the suspension method is mainly used for simulated microgravity tests on the ground. By establishing a suspension system and using the ropes partially connected to the inflatable structure to provide tension, the ground microgravity deployment process of the inflatable structure is simulated. However, in actual tests, due to the significant flexible deformation characteristics of the inflatable structure, the structure is significantly affected by gravity except for the wire rope points. The use of local limited point tension cannot achieve uniform gravity compensation for the entire inflatable structure, and it is difficult to simulate the weightlessness effect of the overall structure, resulting in low test accuracy.

[0006] In addition, large-scale space inflatable structures are large in size, and it is difficult to provide the entire inflatable structure with a controllable tension that changes continuously with the deployment process and matches the weight of the deployed part (if the inflatable structure is suspended as a whole for a simulated microgravity deployment test on the ground, a large number of steel wire ropes are required to suspend and fix the inflatable structure in the air to eliminate its own gravity. However, due to the flexibility and large deformation of the inflatable structure, the use of a limited number of connection points for fixation will cause the inflatable structure itself to deform greatly, affecting the inflation deployment process. That is, the fewer the number of steel wire ropes, the smaller the impact on the inflation deployment process. Therefore, a single-point suspension fixation is adopted to connect and fix one end of the inflatable structure to the suspension system, and the main structure of the inflatable structure is placed on the ground. During the expansion and molding process of the inflatable structure, the volume and weight of the deployed part change continuously with the deployment process. Therefore, the suspension system is required to provide a tension that changes continuously with the deployment process and matches the weight of the deployed part to compensate for gravity). Summary of the invention

[0007] The purpose of the present invention is to solve the problems existing in the background technology and to provide a follow-up compensation simulated microgravity test device and method based on air pressure feedback.

[0008] During the ground-based simulated microgravity deployment of the inflatable structure, the internal air pressure will continue to rise. While driving the inflatable structure to unfold and form, the internal pressure will also generate an in-plane force on the inner wall of the inflatable structure to offset part of the deadweight of the structure. Therefore, the compensatory gravity required for the ground-based simulated microgravity deployment of the inflatable structure is provided by the internal pressure force of the inflation and the tension of the steel wire rope. By monitoring the changes in the internal air pressure of the inflatable structure and setting a threshold (the threshold is calibrated through multiple experimental tests), when the air pressure is lower than the threshold, it indicates that the inflation is only used to drive the inflatable structure to unfold. At this time, the compensatory gravity provided by the steel wire rope of the suspension system is saturated; when the air pressure is greater than the threshold, while the inflation drives the inner wall of the inflatable structure to unfold, the force generated by the internal pressure will balance part of the tension of the steel wire rope of the suspension system. At this time, the compensatory gravity provided by the steel wire rope of the suspension system is insufficient, and the steel wire rope of the suspension system is controlled to rise, increase the gravity compensation, and provide a larger microgravity deployment space for the inflatable structure. During the deployment of the inflatable structure, the above operations are repeated continuously to achieve ground-based simulated microgravity deployment.

[0009] To achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0010] A follow-up compensation simulated microgravity test device based on air pressure feedback, including a gantry, an operating table, a thin film silicon pressure sensor, a controller, a laser displacement sensor, a servo inflation system and a suspension system. The suspension system includes a steel wire rope, a stepper motor, a bidirectional self-locking winch and two pulleys;

[0011] An operating table is installed at the lower part of one side wall of the gantry, a controller and a stepper motor are installed on the operating table, a two-way self-locking winch is fixedly installed on the output shaft of the stepper motor, the top of the gantry is fixedly connected to the wheel axles of the two pulleys, the central axes of the two pulleys are parallel to the central axes of the two-way self-locking winch, one end of the steel wire rope is connected to the upper end of the inflatable structure, and the other end of the steel wire rope is fixedly wound around the two pulleys and then wrapped around the two-way self-locking winch, a thin film silicon pressure sensor is fixed on the inflatable structure, and a probe of the thin film silicon pressure sensor is sealed and fixed inside the inflatable structure, the thin film silicon pressure sensor, the laser displacement sensor and the stepper motor are respectively connected to the controller signal, the controller is electrically connected to the power supply, the servo inflation system is connected to the inflatable structure through the inflation pipeline, and the laser displacement sensor is installed on the top of the gantry.

[0012] A method for simulating microgravity test by follow-up compensation based on air pressure feedback, the method comprising the following steps:

[0013] Step 1: Check the test device to make it work properly;

[0014] Step 2: Install the inflatable structure in a folded state;

[0015] Step 3: Set the air pressure threshold for the controller, the range is 0-10MPa;

[0016] Step 4: Set the controller's limit displacement, the range is 0-100m;

[0017] Step 5: The servo inflation system inflates and drives the inflatable structure to unfold;

[0018] Step 6: The thin film silicon pressure sensor monitors the internal pressure of the inflatable structure and feeds the monitoring data back to the controller;

[0019] Step 7: The controller adjusts the tension of the steel wire rope according to the internal pressure of the inflatable structure fed back by the thin film silicon pressure sensor to match the weight of the unfolded part of the inflatable structure;

[0020] If the internal pressure of the inflatable structure is less than the air pressure threshold set in the controller, it indicates that the internal pressure of the inflatable structure is low and the gravity compensation is saturated, and the controller controls the stepper motor to stop working; if the internal pressure of the inflatable structure is greater than the inflation threshold, it indicates that the internal pressure of the inflatable structure is too high and the gravity compensation is insufficient, and the controller starts the stepper motor to rotate the two-way self-locking winch to store the wire rope, thereby increasing the displacement of the inflatable structure in the vertical direction, increasing the pulling force, and the internal pressure of the inflatable structure decreases and is lower than the air pressure threshold;

[0021]

[0022] Where: P is the real-time air pressure value inside the inflatable structure monitored by the thin film silicon pressure sensor;

[0023] P0 is the air pressure threshold set inside the controller;

[0024] Step 8: The laser displacement sensor monitors and records the real-time displacement of the inflatable structure and feeds the data back to the controller;

[0025] Step 9: When the inflatable structure reaches the limit displacement, the stepper motor stops working, and the servo inflation system continues to inflate. The internal pressure of the inflatable structure gradually exceeds the pressure threshold and continues to rise;

[0026] Step 10: When the inflatable structure is fully unfolded and formed, the servo inflation system stops working; a laser displacement sensor is used to monitor and record the displacement data of the inflatable structure, and a thin film silicon pressure sensor is used to monitor the internal pressure of the inflatable structure. The displacement data measured by the laser displacement sensor and the pressure data measured by the thin film silicon pressure sensor are transmitted to the computer through a data acquisition card to analyze the reliability of the inflatable structure's ground simulated microgravity deployment test, and to optimize the inflatable structure's inflation speed, air pressure threshold and folding method-related parameters, providing a judgment basis for the controller.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] 1. The main structure of the test device of the present invention includes a gantry, an operating table, a thin film silicon pressure sensor, a laser displacement sensor, a controller and a suspension system, etc. The internal pressure of the inflatable structure is used as the gravity compensation feedback characterization quantity of the inflatable structure simulating microgravity deployment. The controller controls the stepper motor to adjust the gravity compensation during the deployment of the inflatable structure. The test operation method is simple, fast, reliable and safe.

[0029] 2. The gantry is made of high-rigidity materials and has a high structural bearing capacity. A pulley is installed on it. The steel wire rope passes through the pulley and is connected and fixed to the inflatable structure to offset the overall gravity of the inflatable structure.

[0030] 3. Self-locking rollers are installed at the bottom of the gantry, which can quickly move and arrange the test equipment according to the test requirements, and effectively fix the rollers through self-locking to ensure structural stability.

[0031] 4. The inflatable structure is connected to a thin-film silicon pressure sensor, which monitors the real-time internal air pressure during the deployment of the inflatable structure, and can further analyze the deployment characteristics of the inflatable structure based on the monitoring data (the air pressure data characterizes the changes in the internal air pressure during the deployment of the inflatable structure. The air pressure value fluctuates around the set value, indicating that the test device is working normally. Based on the air pressure data, the simulated low-gravity deployment effect of the inflatable structure can be analyzed and evaluated, and its deployment effect is closely related to relevant parameters such as inflation speed, air pressure threshold, and folding method. Therefore, the inflatable structure simulated low-gravity deployment process can be optimized by changing relevant parameters such as inflation speed, air pressure threshold, and folding method), providing a reference for the in-orbit deployment and forming of the inflatable structure.

[0032] 5. The thin film silicon pressure sensor is connected to the controller signal, and the controller is connected to the stepper motor signal. The controller controls the stepper motor in real time according to the changes in the internal pressure of the inflatable structure. The test process has a high degree of automation and fast response, which effectively improves the test accuracy.

[0033] 6. The controller sets the air pressure threshold, and adjusts the internal pressure of the inflatable structure through the controller to fluctuate near the threshold. The internal pressure of the inflatable structure provides surface support for the unfolded part of the inflatable structure (the inflatable structure is driven to unfold by the increase of internal air pressure, and its unfolded part is conformed by the internal air pressure, that is, the internal air pressure acts on its inner wall surface, which has an in-plane supporting force), effectively overcoming the influence of gravity caused by the local limited point support of the suspension.

[0034] 7. The controller controls the stepper motor to rotate and adjust the tension of the wire rope according to the relationship between the internal pressure of the inflatable structure and the air pressure threshold. If the internal pressure of the inflatable structure is less than the air pressure threshold, it indicates that the internal pressure of the inflatable structure is low and the gravity compensation is saturated; if the internal pressure of the inflatable structure is greater than the air pressure threshold, it indicates that the internal pressure of the inflatable structure is too high and the gravity compensation is insufficient. The stepper motor is started to increase the vertical displacement of the inflatable structure, and the internal pressure of the inflatable structure decreases accordingly. Using the controller to control the continuous change of gravity compensation can provide a controllable tension that changes continuously with the deployment process of the inflatable structure and matches the weight of the deployed part, effectively improving the accuracy of the ground simulated microgravity test of the inflatable structure.

[0035] 8. The air pressure threshold in the controller can be adjusted according to the test requirements. It can take into account parameters such as the volume, mass, and inflation speed of the inflatable structure. Through multiple tests, the empirical parameters of the inflation threshold can be optimized to improve the test reliability and expand the application scope of the test device to meet the needs of ground simulated microgravity tests of various space inflatable structures.

[0036] 9. The stepper motor and the two-way self-locking winch rotate coaxially. When the stepper motor rotates forward, the two-way self-locking winch collects the wire rope and lifts the inflatable structure through the pulley; when the stepper motor rotates reversely, the two-way self-locking winch releases the wire rope and the inflatable structure descends in the vertical direction. The test operation is automated and has high stability.

[0037] 10. A laser displacement sensor is installed on the top of the gantry to monitor the vertical displacement of the inflatable structure. According to the displacement data recorded by the laser displacement sensor, the displacement, speed and acceleration analysis during the vertical deployment of the inflatable structure can be carried out (the laser displacement sensor is used to monitor and record the displacement data of the inflatable structure, and transmitted to the computer through the data acquisition card), which is convenient for evaluating the deployment reliability of the inflatable structure and further optimizing the folding and deployment plan of the inflatable structure.

[0038] 11. The laser displacement sensor is connected to the controller signal, and a limit displacement is set in the controller. When the inflatable structure reaches the limit displacement, the controller immediately blocks the stepper motor from continuing to lift the inflatable structure to avoid collision between the inflatable structure and the top of the gantry, prevent test overload, and effectively ensure the safety and reliability of the test process.

[0039] 12. The inflatable structure is driven and unfolded by a servo inflation system. The inflation speed and time are controllable, the test cost is low and the operation is quick. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a structural schematic diagram of the follow-up compensation simulated microgravity test device based on air pressure feedback of the present invention.

[0041] Figure 1 The names and numbers of the components involved are as follows:

[0042] Gantry 1, operating table 2, thin film silicon pressure sensor 3, controller 4, stepper motor 5, bidirectional self-locking winch 6, laser displacement sensor 7, servo inflation system 8, pulley 9, wire rope 10, inflation structure 11, inflation pipeline 12. DETAILED DESCRIPTION

[0043] The technical solution of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0044] Specific implementation method 1: Figure 1 As shown, this embodiment describes a follow-up compensation simulated microgravity test device based on air pressure feedback, including a gantry 1, an operating table 2, a thin film silicon pressure sensor 3, a controller 4, a laser displacement sensor 7, a servo inflation system 8 and a suspension system, and the suspension system includes a steel wire rope 10, a stepper motor 5, a bidirectional self-locking winch 6 and two pulleys 9;

[0045] The operating table 2 is installed at the lower part of one side wall of the gantry 1, the controller 4 and the stepper motor 5 are installed on the operating table 2, the two-way self-locking winch 6 is fixedly mounted on the output shaft of the stepper motor 5, the top of the gantry 1 is fixedly connected to the axles of the two pulleys 9 (the two pulleys 9 are rotatably connected to their respective axles through bearings), the central axes of the two pulleys 9 are parallel to the central axis of the two-way self-locking winch 6, one end of the wire rope 10 is connected to the upper end of the inflatable structure 11, and the other end of the wire rope 10 is fixedly wound around the two pulleys 9 and then wound around the two-way self-locking winch 6 The thin film silicon pressure sensor 3 is fixed on the inflatable structure 11, and the probe of the thin film silicon pressure sensor 3 is sealed and fixed inside the inflatable structure 11, the thin film silicon pressure sensor 3, the laser displacement sensor 7 and the stepper motor 5 are respectively connected to the controller 4 signal, the controller 4 is electrically connected to the power supply, the servo inflation system 8 is connected to the inflatable structure 11 through the inflation pipeline 12 (the inflatable structure 11 is inflated and expanded by the servo inflation system 8), and the laser displacement sensor 7 is installed on the top of the gantry 1 (for monitoring the expansion displacement of the inflatable structure 11).

[0046] The gantry 1 is a suspension support structure of the inflatable structure 11. The gantry 1 is made of high-rigidity materials (such as aluminum alloy, stainless steel, etc.). The size of the gantry 1 is determined by the unfolded size of the inflatable structure 11 test specimen, and its height range is 1-50m.

[0047] The thin film silicon pressure sensor 3 is connected to the inflatable structure 11, and is used to monitor the real-time internal air pressure of the inflatable structure 11 during its deployment, and feed the data back to the controller 4. The controller 4 controls the stepper motor 5 to rotate, and pulls the steel wire rope 10 through the bidirectional self-locking winch 6 to provide gravity compensation for the inflatable structure 11. The controller 4 sets the limit displacement to ensure the safe deployment of the inflatable structure 11. The range of the thin film silicon pressure sensor 3 is determined by the test requirements, and the air pressure range that can be monitored is 0-10MPa.

[0048] The controller 4 is the core processing component of the test device of the present invention. The controller 4 is mainly composed of a PLC circuit (which is the prior art), and the controller 4 sets the air pressure threshold. The air pressure threshold is the critical value of the internal feedback air pressure during the ground simulated microgravity deployment of the inflatable structure 11. It is necessary to fully consider the parameters such as the volume, mass, and inflation speed of the inflatable structure 11. The empirical parameters determined through multiple tests and adjustments have an air pressure threshold range of 0-10MPa for the controller 4. Normally, the air pressure threshold of the controller 4 increases with the increase of the volume, mass, and inflation speed of the inflatable structure 11.

[0049] ① The controller 4 is internally provided with an air pressure threshold, and the real-time internal pressure of the inflatable structure 11 measured by the thin-film silicon pressure sensor 3 is compared with the threshold, and the stepper motor 5 is controlled to pull the steel wire rope 10 to adjust the tension. If the internal pressure of the inflatable structure 11 is less than the air pressure threshold, it indicates that the internal pressure of the inflatable structure 11 is low and the gravity compensation is saturated; if the internal pressure of the inflatable structure 11 is greater than the air pressure threshold, it indicates that the internal pressure of the inflatable structure 11 is too high and the gravity compensation is insufficient, and the stepper motor 5 needs to be started to increase the vertical displacement of the inflatable structure 11, increase the tension and reduce the internal pressure of the inflatable structure 11, and provide the inflatable structure 11 with a controllable tension that changes continuously with the unfolding process and matches the weight of the unfolded part; ② The inflatable structure 11 reaches suspension balance in the vertical direction, indicating that the compensation gravity required for the unfolded part matches the tension provided by the suspension system.

[0050] The controller 4 is connected to the laser displacement sensor 7 signal. The laser displacement sensor 7 is used to monitor the vertical displacement of the inflatable structure 11. When the inflatable structure 11 reaches the limit displacement in the vertical direction, the controller 4 immediately blocks the stepper motor 5 from continuing to lift the inflatable structure 11. The range of the laser displacement sensor 7 is determined by the height of the gantry 1, and its range is 0-50m. The limit displacement value (limit displacement: the vertical displacement limit allowed by the gantry 1 during the deployment of the inflatable structure 11. The range of the laser displacement sensor 7 can be greater than the displacement limit, but the limit displacement value is set in the controller 4) is mainly used to prevent test overload, and its value is determined according to parameters such as the height of the gantry 1 and the size of the inflatable structure 11.

[0051] The stepper motor 5 rotates coaxially with the bidirectional self-locking winch 6 , and the bidirectional self-locking winch 6 is used to realize the storage and release of the steel wire rope 10 .

[0052] The inflatable structure 11 is in communication with the servo inflation system 8 and is deployed by inflation drive.

[0053] Furthermore, self-locking rollers 13 are installed at the bottom of the two side walls of the gantry 1.

[0054] Specific implementation method 2: Figure 1 As shown, this embodiment is a method for implementing a simulated microgravity test based on air pressure feedback by using the device described in the first embodiment, and the method includes the following steps:

[0055] Step 1: Check the test device to make it work properly (check the structural fixation and connection reliability of the gantry 1 and the pulley 9, power on and check the thin film silicon pressure sensor 3, the controller 4, the stepper motor 5, the two-way self-locking winch 6, the laser displacement sensor 7, and the servo inflation system 8, so that the above components are in normal working condition);

[0056] Step 2: installing the inflatable structure 11 in a folded state (i.e., the test object);

[0057] Step 3: setting an air pressure threshold for the controller 4 (the air pressure threshold is the critical value of the internal feedback air pressure during the ground simulated microgravity deployment of the inflatable structure 11, and it is necessary to fully consider the volume, mass, inflation speed and other parameters of the inflatable structure 11, and the empirical parameters determined through multiple tests and adjustments. Under normal circumstances, the air pressure threshold increases with the increase of the volume, mass, inflation speed and other parameters of the inflatable structure 11), and its range is 0-10MPa;

[0058] Step 4: Set the limit displacement of the controller 4 (the limit displacement value of the controller 4 is the critical value in the vertical direction when the inflatable structure 11 is fully deployed, which is used to prevent test overload and improve test safety. The limit displacement value is mainly determined according to parameters such as the height of the gantry 1 and the size of the inflatable structure 11), and its range is 0-100m;

[0059] Step 5: The servo inflation system 8 inflates and drives the inflatable structure 11 to unfold (after the test starts, the servo inflation system 8 starts working first and continuously inflates the inflatable structure 11. The inflatable structure 11 is driven to unfold by the inflation action, and the internal pressure increases accordingly);

[0060] Step 6: The thin film silicon pressure sensor 3 monitors the internal pressure of the inflatable structure 11 and feeds back the monitoring data to the controller 4 (the thin film silicon pressure sensor 3 monitors and records the real-time air pressure inside the inflatable structure 11);

[0061] Step 7: The controller 4 adjusts the tension of the steel wire rope 10 according to the internal pressure of the inflatable structure 11 fed back by the thin film silicon pressure sensor 3 to match the weight of the unfolded part of the inflatable structure 11;

[0062] If the internal pressure of the inflatable structure 11 is less than the air pressure threshold set in the controller 4, it indicates that the internal pressure of the inflatable structure 11 is low and the gravity compensation is saturated, and the controller 4 controls the stepper motor 5 to stop working; if the internal pressure of the inflatable structure 11 is greater than the inflation threshold, it indicates that the internal pressure of the inflatable structure 11 is too high and the gravity compensation is insufficient, and the controller 4 starts the stepper motor 5 to rotate the two-way self-locking winch 6 to store the wire rope 10, thereby increasing the displacement of the inflatable structure 11 in the vertical direction, increasing the tension, and the internal pressure of the inflatable structure 11 decreases and is lower than the air pressure threshold;

[0063]

[0064] Wherein: P is the real-time air pressure value inside the inflatable structure 11 monitored by the thin film silicon pressure sensor 3;

[0065] P0 is the air pressure threshold value set inside the controller 4;

[0066] During the entire inflation process of the inflatable structure 11, the stepper motor 5 is continuously started, stopped, and started.

[0067] Step 8: The laser displacement sensor 7 monitors and records the real-time displacement of the inflatable structure 11 (during the deployment of the inflatable structure 11, its vertical displacement increases continuously, and the laser displacement sensor 7 monitors and records the real-time displacement of the inflatable structure 11), and feeds the data back to the controller 4;

[0068] Step nine: When the inflatable structure 11 reaches the limit displacement, the stepper motor 5 stops working (as the inflatable structure 11 continues to unfold and reaches the limit displacement, it means that it has been fully unfolded in the vertical direction. At this time, the controller 4 stops running the stepper motor 5, and the inflatable structure 11 will remain fixed in the vertical direction), the servo inflation system 8 continues to inflate, and the internal pressure of the inflatable structure 11 gradually exceeds the air pressure threshold and continues to rise;

[0069] Step 10: When the inflatable structure 11 is fully unfolded and formed, the servo inflation system 8 stops working (as the internal pressure of the inflatable structure 11 continues to rise, its structure will be fully unfolded and formed, and when the predetermined internal pressure of the inflatable structure 11 (the fully unfolded pressure value of the inflatable structure 11) is reached, inflation can be stopped); the laser displacement sensor 7 is used to monitor and record the displacement data of the inflatable structure 11, and the thin film silicon pressure sensor 3 is used to monitor the internal pressure of the inflatable structure 11, and the displacement data and pressure data are transmitted to the computer through the data acquisition card to analyze the reliability of the ground simulated microgravity unfolding test of the inflatable structure 11 (the air pressure data represents the changes in the internal air pressure during the unfolding process of the inflatable structure 11, The air pressure value remains fluctuating near the set value, which indicates that the test device of the present invention is working normally), and the inflation speed, air pressure threshold and folding method related parameters of the inflatable structure 11 are optimized (according to the air pressure, displacement and other data, the low-gravity simulation deployment effect of the inflatable structure 11 is analyzed and evaluated, and its deployment effect is closely related to the inflation speed, air pressure threshold and folding method (including Z-type folding, accordion folding, star-shaped folding, torsion folding) related parameters. According to the experimental results, the influence of different folding methods on its deployment characteristics is analyzed and evaluated. Therefore, by changing the inflation speed, air pressure threshold and folding method related parameters, the low-gravity simulation deployment process of the inflatable structure 11 is optimized).

[0070] Furthermore, step two is specifically as follows: the folded inflatable structure 11 is fixedly connected to one end of the steel wire rope 10, the other end of the steel wire rope 10 passes around two pulleys 9 and is wound around the bidirectional self-locking winch 6, the probe of the thin film silicon pressure sensor 3 is sealed and fixed inside the inflatable structure 11, and the inflatable structure 11 is connected to the servo inflation system 8 through the inflation pipeline 12.

[0071] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations within the meaning and range of equivalents of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0072] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A follow-up compensation simulated microgravity test device based on air pressure feedback, characterized in that: It comprises a gantry (1), an operating table (2), a thin film silicon pressure sensor (3), a controller (4), a laser displacement sensor (7), a servo inflation system (8) and a suspension system, wherein the suspension system comprises a steel wire rope (10), a stepping motor (5), a bidirectional self-locking winch (6) and two pulleys (9); The operating table (2) is installed at the lower part of one side wall of the gantry (1), the controller (4) and the stepping motor (5) are installed on the operating table (2), the bidirectional self-locking winch (6) is fixedly installed on the output shaft of the stepping motor (5), the top of the gantry (1) is fixedly connected to the wheel axles of the two pulleys (9), the central axes of the two pulleys (9) are parallel to the central axes of the bidirectional self-locking winch (6), one end of the steel wire rope (10) is connected to the upper end of the inflatable structure (11), and the other end of the steel wire rope (10) is fixedly wound around the two pulleys (9) and then wound around the inflatable structure (11). On the bidirectional self-locking winch (6), a thin film silicon pressure sensor (3) is fixed on the inflatable structure (11), and a probe of the thin film silicon pressure sensor (3) is sealed and fixed inside the inflatable structure (11), the thin film silicon pressure sensor (3), the laser displacement sensor (7) and the stepping motor (5) are respectively connected to the controller (4) for signal, the controller (4) is electrically connected to the power supply, the servo inflation system (8) is connected to the inflatable structure (11) through the inflation pipeline (12), and the laser displacement sensor (7) is installed on the top of the gantry (1); The thin film silicon pressure sensor (3) monitors the internal pressure of the inflatable structure (11) and feeds back the monitoring data to the controller (4); the controller (4) adjusts the tension of the steel wire rope (10) according to the internal pressure of the inflatable structure (11) fed back by the thin film silicon pressure sensor (3) so as to match the weight of the unfolded part of the inflatable structure (11); If the internal pressure of the inflatable structure (11) is less than the air pressure threshold value set in the controller (4), it indicates that the internal pressure of the inflatable structure (11) is low and the gravity compensation is saturated, and the controller (4) controls the stepper motor (5) to stop working; if the internal pressure of the inflatable structure (11) is greater than the inflation threshold value, it indicates that the internal pressure of the inflatable structure (11) is too high and the gravity compensation is insufficient, and the controller (4) starts the stepper motor (5) to rotate the bidirectional self-locking winch (6) to store the steel wire rope (10), thereby increasing the displacement of the inflatable structure (11) in the vertical direction, increasing the tension, and the internal pressure of the inflatable structure (11) decreases and is lower than the air pressure threshold value; Wherein: P is the real-time air pressure value inside the inflatable structure (11) monitored by the thin film silicon pressure sensor (3); P0 is the air pressure threshold value set inside the controller (4).

2. The follow-up compensation simulated microgravity test device based on air pressure feedback according to claim 1 is characterized in that: Self-locking rollers (13) are installed at the bottoms of the two side walls of the gantry (1).

3. A method for implementing a simulated microgravity test with follow-up compensation based on air pressure feedback using the test device according to claim 1 or 2, characterized in that: The method comprises the following steps: Step 1: Check the test device to make it work properly; Step 2: Installing the folded inflatable structure (11); Step 3: Setting the air pressure threshold value for the controller (4) in the range of 0-10 MPa; Step 4: Set the limit displacement of the controller (4) to a range of 0-100m; Step 5: the servo inflation system (8) inflates and drives the inflatable structure (11) to unfold; Step 6: The thin film silicon pressure sensor (3) monitors the internal pressure of the inflatable structure (11) and feeds back the monitoring data to the controller (4); Step 7: The controller (4) adjusts the tension of the steel wire rope (10) according to the internal pressure of the inflatable structure (11) fed back by the thin film silicon pressure sensor (3) so as to match the weight of the unfolded part of the inflatable structure (11); If the internal pressure of the inflatable structure (11) is less than the air pressure threshold value set in the controller (4), it indicates that the internal pressure of the inflatable structure (11) is low and the gravity compensation is saturated, and the controller (4) controls the stepper motor (5) to stop working; if the internal pressure of the inflatable structure (11) is greater than the inflation threshold value, it indicates that the internal pressure of the inflatable structure (11) is too high and the gravity compensation is insufficient, and the controller (4) starts the stepper motor (5) to rotate the bidirectional self-locking winch (6) to store the steel wire rope (10), thereby increasing the displacement of the inflatable structure (11) in the vertical direction, increasing the tension, and the internal pressure of the inflatable structure (11) decreases and is lower than the air pressure threshold value; Wherein: P is the real-time air pressure value inside the inflatable structure (11) monitored by the thin film silicon pressure sensor (3); P0 is the air pressure threshold value set inside the controller (4); Step 8: The laser displacement sensor (7) monitors and records the real-time displacement of the inflatable structure (11), and feeds the data back to the controller (4); Step nine: When the inflatable structure (11) reaches the limit displacement, the stepper motor (5) stops working, and the servo inflation system (8) continues to inflate, and the internal pressure of the inflatable structure (11) gradually exceeds the pressure threshold and continues to rise; Step 10: When the inflatable structure (11) is fully unfolded and formed, the servo inflation system (8) stops working; the laser displacement sensor (7) is used to monitor and record the displacement data of the inflatable structure (11); the thin film silicon pressure sensor (3) is used to monitor the internal pressure of the inflatable structure (11); the displacement data measured by the laser displacement sensor (7) and the pressure data measured by the thin film silicon pressure sensor (3) are transmitted to the computer through the data acquisition card, so as to analyze the reliability of the ground simulated microgravity unfolding test of the inflatable structure (11), and optimize the inflation speed, air pressure threshold and folding method related parameters of the inflatable structure (11), so as to provide a judgment basis for the controller (4).

4. The test method according to claim 3, characterized in that: Step 2 specifically comprises: fixing the folded inflatable structure (11) to one end of the steel wire rope (10), passing the other end of the steel wire rope (10) around two pulleys (9) and winding around a bidirectional self-locking winch (6), sealing and fixing the probe of the thin film silicon pressure sensor (3) inside the inflatable structure (11), and connecting the inflatable structure (11) to the servo inflation system (8) through an inflation pipeline (12).

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