A three-axis air-floating platform and its simulation test anti-dumping control method

Abstract

The invention discloses a three-axis air floating platform and a simulation test anti-dumping control method thereof. The three-axis air floating platform is provided with an anti-dumping protection device. In the anti-dumping control method, a first angle, a second angle and a first angular velocity are preset, and the real-time angle and the real-time angular velocity of the three-axis air floating platform in the process of executing a simulation test task are collected, and the real-time angle and the real-time angular velocity are respectively compared with the preset angle and the angular velocity. When it is judged that the three-axis air floating platform has a risk of dumping, a control method combining emergency risk avoidance control and normal risk avoidance control is adopted to perform risk avoidance operation. The working reliability of the three-axis air floating platform can be further improved by combining mechanical protection with software control protection.

Description

Technical Field

[0001] The invention relates to the technical field of spacecraft ground physics simulation, and in particular to a three-axis air floating platform and a simulation test anti-dumping control method thereof. Background Art

[0002] The air-floating platform relies on compressed air to form an air film between the air-floating bearing and the bearing seat, so that the air-floating platform floats and achieves a relative motion condition that is approximately frictionless, in order to simulate the environment of small disturbance torques to which the satellite is subjected in outer space. As a satellite motion simulator, the three-degree-of-freedom air-floating platform supported by spherical air-floating bearings can not only simulate the attitude motion required in the three-axis directions, but also simulate the three-axis attitude coupling dynamics of the satellite. Physical simulation through the air-floating platform plays an important role, and it is an indispensable tool for program demonstration and function verification. Simulation practice has proved that simulation using the air-floating platform not only plays an important role in the verification of satellite attitude control systems, but also can significantly improve the cost-effectiveness of satellites, reduce risks, and shorten the R&D cycle.

[0003] The micro-disturbance torque requirement of the three-axis air-floating table is better than ≤5mNm, the rotation angle range around the two horizontal axes is ±30°, and the rotation angle range around the vertical axis is 360°. In order to improve the safety of physical simulation tests in a micro-disturbance torque environment and prevent the air-floating control unit on the three-axis air-floating table from tipping over during leveling or testing, causing damage to the test equipment or its own equipment, it is necessary to design a three-axis air-floating table limit protection device and perform anti-dumping control to ensure that the instrument platform body does not suffer impact damage caused by large-angle tipping during attitude control debugging or testing. At present, most anti-tip schemes are mainly concentrated on mechanical structures. For example, the application number is 201510947471.8, and the invention name is a three-axis air-floating table umbrella-shaped retractable limit protection device. Six umbrella-shaped retractable limit protection units are installed at the center of the lower end of the instrument platform through the air-floating table ball bearing to solve the problem of the three-axis air-floating table causing damage to the test satellite equipment or its own equipment due to the tipping of the instrument platform during the test. The protection degree of the above scheme is limited, and there is a lack of research on emergency braking and preventive control methods for anti-dumping. Therefore, it is very necessary to study the anti-dumping control method of the three-axis air floating platform. Summary of the invention

[0004] In view of the above problems, the present invention designs a control method for preventing tipping during simulation testing based on the existing light-load three-axis air floating platform, and further improves the existing light-load three-axis air floating platform. For the convenience of description, the light-load three-axis air floating platform is referred to as the three-axis air floating platform in the subsequent description.

[0005] On one hand, the present invention provides a three-axis air-floating platform simulation test anti-dumping control method, comprising the following steps:

[0006] S1, preset a first angle, a second angle and a first angular velocity, mount the external object to be tested on the three-axis air bearing platform, initialize the three-axis air bearing platform, and set the simulation mode and parameters;

[0007] S2. The three-axis air floating platform performs a simulation test task. The air floating test device of the three-axis air floating platform collects the posture information of the three-axis air floating platform during the simulation test. The posture information includes the real-time angle and real-time angular velocity of the three-axis air floating platform.

[0008] S3, comparing the real-time angle of the three-axis air-floating platform with the first angle, if the real-time angle is smaller than the first angle, executing step S7, otherwise, executing step S4;

[0009] S4, comparing the real-time angle of the three-axis air-floating platform with the second angle, and comparing the real-time angular velocity of the three-axis air-floating platform with the first angular velocity. If the real-time angle is less than the second angle and the real-time angular velocity is less than the first angular velocity, executing step S5; otherwise, if the real-time angle is greater than or equal to the second angle or the real-time angular velocity is greater than or equal to the first angular velocity, executing step S6;

[0010] S5, perform normal risk avoidance control on the three-axis air floating platform and execute step S7;

[0011] S6, perform emergency risk avoidance control on the three-axis air floating platform, and execute step S8;

[0012] S7, check whether the three-axis air bearing platform simulation test system has completed the simulation test task, if yes, execute step S8, otherwise, return to step S2;

[0013] S8. The three-axis air bearing platform simulation test system ends the simulation test and outputs the simulation test results.

[0014] Preferably, the calculation formula of the first angular velocity in S1 is specifically:

[0015] ;

[0016] In the formula, is the preset first angular velocity, is the maximum output torque of the three-axis air bearing actuator, is the moment of inertia of the three-axis air bearing platform, is the preset first angle, The second preset angle.

[0017] Preferably, in S5, the three-axis air floating platform is normally controlled to avoid danger, specifically, the real-time angle of the three-axis air floating platform is adjusted by outputting a control torque through the actuator of the three-axis air floating platform, so that the real-time angle is smaller than a preset first angle.

[0018] Preferably, the actuator includes a cold air thrust unit and a reaction flywheel, and the real-time angle of the three-axis air floating platform is adjusted by outputting a control torque through the actuator of the three-axis air floating platform so that the real-time angle is less than a preset first angle, specifically including:

[0019] S51, presetting a second angular velocity, wherein the second angular velocity is less than the first angular velocity;

[0020] S52, comparing the real-time angular velocity of the three-axis air-floating platform with the second angular velocity, if the real-time angular velocity of the three-axis air-floating platform is less than or equal to the second angular velocity, executing step S53, otherwise, executing step S54;

[0021] S53, adjusting the real-time angle of the three-axis air bearing platform by outputting a torque of a reaction flywheel;

[0022] S54, adjusting the real-time angle of the three-axis air-floating platform by outputting torques through the cold air thrust unit and the reaction flywheel respectively;

[0023] S55, obtaining the real-time angle of the three-axis air-floating platform, comparing the real-time angle with the first angle, if the real-time angle is greater than or equal to the first angle, returning to step S52, otherwise, ending the normal risk avoidance control.

[0024] Preferably, in S6, emergency avoidance control is performed on the three-axis air floating platform, specifically, the actuator of the three-axis air floating platform is controlled to stop running, the limit protection device of the three-axis air floating platform is started, and the air floating test device is supported by the limit protection device.

[0025] Another aspect of the present invention provides a three-axis air floating platform, which uses the above-mentioned three-axis air floating platform simulation test anti-dumping control method to perform anti-dumping control during the simulation test. The three-axis air floating platform includes:

[0026] An air flotation test device is used to carry an external test piece for air flotation test, including a support connection platform, a control unit arranged on the outer side of the support connection platform, an air flotation ball arranged at the center of the bottom surface of the support connection platform, and a table counterweight placed on the support connection platform. The external test piece is fixedly mounted on the upper surface of the support connection platform. The control unit includes a reaction flywheel for adjusting and controlling the posture of the air flotation test device. The air flotation ball includes a flat plate portion and a spherical portion.

[0027] The air-floating support device is used to support the air-floating test device, and includes a support frame, the top surface of the support frame is provided with an air-floating seat, the air-floating seat is provided with a spherical groove, and the bottom surface of the support connection platform is movably connected to the air-floating seat of the support frame through the spherical part on the air-floating ball;

[0028] The cold air thrust unit is installed above the supporting connection platform, and its center of gravity coincides with the center of the air floating ball, and is used to realize the balanced setting of the air floating test device on the air floating support device;

[0029] The limit protection device includes a support protection component and an air flotation protection component. The support protection component is mounted on the support frame and can move vertically along the support frame body. The air flotation protection component is fixedly connected to the edge of the bottom surface of the support connection platform and can move with the support connection platform. The support protection component can abut against the air flotation protection component to support the air flotation test device, thereby realizing emergency risk avoidance control of the three-axis air flotation platform.

[0030] Preferably, the support and protection assembly includes a support plate, a cylinder fixing seat and a thrust cylinder. The cylinder fixing seat is mounted on the top of the support frame, the thrust cylinder is mounted on the cylinder fixing seat, the support plate is mounted on the top of the thrust cylinder, and the air flotation protection assembly includes a protective plate. The protective plate is fixedly connected to the lower surface of the support connection platform. The support plate can be pushed by the thrust cylinder to move vertically along the support frame, so that the support plate and the protective plate are abutted to support the air flotation test device, thereby realizing emergency risk avoidance control of the three-axis air flotation platform.

[0031] Preferably, the control unit also includes a leveling component for leveling the flotation test device, and the leveling component includes: a plurality of inclined brackets, arranged in a circular array around the center line of the supporting connection platform and on the edge of the supporting connection platform; a plurality of coarse leveling modules, respectively installed on the plurality of inclined brackets in an inclined manner and away from one side of the supporting connection platform; a plurality of fine leveling modules, equidistantly arranged at the bottom of the supporting connection platform; and a plurality of fine leveling modules, respectively installed on the plurality of inclined brackets in an inclined manner.

[0032] Preferably, the three-axis air flotation platform also includes a limit buffer device, which includes a vertical limit buffer and a transverse limit buffer. The vertical limit buffer is arranged along the circumference of the support frame and is located above the cylinder fixing seat. It is used for buffering the contact between the support frame and the lower edge of the supporting connecting platform when the three-axis air flotation platform is deflected at a large angle. The transverse limit buffer is hollow cylindrical and is sleeved on the circumference of the air flotation seat. It is used for buffering the contact between the flat plate part of the air flotation ball and the upper edge of the air flotation seat when the three-axis air flotation platform is deflected at a large angle.

[0033] Preferably, the three-axis air-floating platform further includes an anti-fall device, which includes a protection frame and a plurality of protection pads. The protection frame is arranged around the air-floating support device and is located below it. The plurality of protection pads are spliced ​​and placed on the protection frame.

[0034] The above-mentioned three-axis air floating platform and its simulation test anti-dumping control method, the three-axis air floating platform is provided with an anti-dumping protection device, the anti-dumping control method presets a first angle, a second angle and a first angular velocity, collects the real-time angle and real-time angular velocity of the three-axis air floating platform during the execution of the simulation test task, and compares the real-time angle and real-time angular velocity with the preset angle and angular velocity respectively. When it is judged that the three-axis air floating platform has a risk of dumping, a control method combining emergency avoidance control and normal avoidance control is adopted to perform a risk avoidance operation. The method of combining mechanical protection and software control protection can further improve the working reliability of the three-axis air floating platform. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a flow chart of an anti-dumping control method for a three-axis air-floating platform simulation test;

[0036] Figure 2 It is a schematic diagram of the overall structure of the three-axis air bearing platform;

[0037] Figure 3 It is a longitudinal cross-sectional view of the triaxial air-floating platform in an extreme state for emergency avoidance;

[0038] Figure 4 It is a schematic diagram of the installation structure of the air-floating support device and the cold air thrust unit in the three-axis air-floating platform;

[0039] Figure 5 It is a structural schematic diagram of a support connection platform in an air-floating support device;

[0040] Figure 6 It is a schematic diagram of the structure of the air-floating ball in the air-floating support device;

[0041] Figure 7 It is a schematic diagram of the structure of the cold air thrust unit in the three-axis air bearing platform;

[0042] Figure 8 It is a schematic diagram of the structure of the limit protection device in the three-axis air-floating table;

[0043] Fig. 9 yes Figure 3 A local enlarged schematic diagram of the middle A;

[0044] Fig.10 yes Figure 3 A partial enlarged schematic diagram of point B in the middle;

[0045] Fig.11 It is a schematic diagram of the structure of the anti-fall device.

[0046] Description of reference numerals:

[0047] 1. Air flotation test device; 11. Support connection platform; 12. Control unit; 121. Tilt bracket; 122. Coarse leveling module; 123. Fine leveling module; 124. Fine leveling module; 13. Air flotation ball; 131. Flat plate; 132. Spherical part;

[0048] 2. Air floating support device; 21. Support frame; 211. Air floating seat; 22. Load-bearing platform; 23. Support tripod;

[0049] 3. Air conditioning thrust unit;

[0050] 4. Limit protection device; 41. Support protection assembly; 411. Support plate; 412. Cylinder fixing seat; 413. Thrust cylinder; 42. Air flotation protection assembly; 421. Protection plate;

[0051] 5. Limiting buffer device; 51. Vertical limiting buffer; 52. Horizontal limiting buffer;

[0052] 6. Anti-fall device; 61. Protection frame; 62. Protection pad. DETAILED DESCRIPTION

[0053] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings.

[0054] See also Figure 1 , Figure 1 The flowchart of a three-axis air-floating platform simulation test anti-dumping control method in one embodiment of the present invention is as follows:

[0055] S1, preset first angle , Second Angle and the first angular velocity , install the external test piece on the three-axis air bearing table, initialize the three-axis air bearing table, and set the simulation mode and parameters.

[0056] Specifically, the first angle is preset , Second Angle ( > ), the first angular velocity The value of and the moment of inertia of the three-axis air bearing platform And the preset first angle , Second Angle related.

[0057] Furthermore, the calculation formula of the first angular velocity in S1 is specifically:

[0058] ;

[0059] In the formula, is the preset first angular velocity, is the maximum output torque of the three-axis air bearing actuator, is the moment of inertia of the three-axis air bearing platform, is the preset first angle, The second preset angle, the maximum output torque and the moment of inertia of the three-axis air bearing table It can be calculated before conducting simulation tests.

[0060] After setting the angle and angular velocity values, install the external test piece on the three-axis air bearing table, turn on the power, initialize the system, set the simulation mode and parameters on the human-machine interface, and turn on the safety protection function.

[0061] S2. The three-axis air floating platform performs a simulation test task. The air floating test device of the three-axis air floating platform collects the posture information of the three-axis air floating platform during the simulation test. The posture information includes the real-time angle and real-time angular velocity of the three-axis air floating platform.

[0062] S3, the real-time angle and the first angle of the three-axis air-floating table Compare, if the real-time angle is smaller than the first angle , then execute step S7, otherwise, execute step S4.

[0063] S4, the real-time angle of the three-axis air-floating table and the second angle Compare the real-time angular velocity of the three-axis air-floating platform with the first angular velocity Compare, if the real angle is smaller than the second angle And the real-time angular velocity is less than the first angular velocity , execute step S5, otherwise, if the real-time angle is greater than or equal to the second angle Or the real-time angular velocity is greater than or equal to the first angular velocity , execute step S6;

[0064] S5. Perform normal risk avoidance control on the three-axis air-floating platform and execute step S7.

[0065] Specifically, when the real-time angle of the three-axis air-bearing platform is less than the second angle And the real-time angular velocity is less than the first angular velocity Normal risk avoidance control is specifically to adjust the real-time angle of the three-axis air floating platform by outputting a control torque through the actuator of the three-axis air floating platform until the real-time angle is less than the preset first angle. , end normal risk avoidance control, and then continue with the simulation test.

[0066] Furthermore, the actuator includes a cold air thrust unit and a reaction flywheel, and the real-time angle of the three-axis air floating platform is adjusted by outputting a control torque through the actuator of the three-axis air floating platform, so that the real-time angle is less than the preset first angle. , specifically including:

[0067] S51, presetting a second angular velocity, wherein the second angular velocity is less than the first angular velocity;

[0068] S52, comparing the real-time angular velocity of the three-axis air-floating platform with the second angular velocity, if the real-time angular velocity of the three-axis air-floating platform is less than or equal to the second angular velocity, executing step S53, otherwise, executing step S54;

[0069] S53, adjusting the real-time angle of the three-axis air bearing platform by outputting a torque of a reaction flywheel;

[0070] S54, adjusting the real-time angle of the three-axis air-floating platform by outputting torque through the cold air thrust unit and the reaction flywheel;

[0071] S55, obtain the real-time angle of the three-axis air-floating platform, and compare the real-time angle and the first angle Compare, if the real-time angle is greater than or equal to the first angle , then return to step S52, otherwise, end the normal risk avoidance control.

[0072] Specifically, the actuator of the three-axis air-floating platform includes a cold air thrust unit and a reaction flywheel, and there is a large difference in the torque output by the two. Therefore, the normal risk avoidance control of the three-axis air-floating platform needs to be carried out in stages. At this time, the second angular velocity is preset. ( < ), the maximum output torque of the general cold air thrust unit is much greater than the maximum output torque of the reaction flywheel, so the normal risk avoidance can be divided into two stages. If the real-time angular velocity of the three-axis air floating platform is less than or equal to the second angular velocity , the reaction flywheel output torque is used for normal risk avoidance control. If the real-time angular velocity of the three-axis air floating platform is greater than the second angular velocity, the cold air thrust unit and the reaction flywheel are used to jointly output torque for normal risk avoidance control.

[0073] S6. Perform emergency risk avoidance control on the three-axis air-floating platform and execute step S8.

[0074] Specifically, if the real-time angle is greater than or equal to the second angle Or the real-time angular velocity is greater than or equal to the first angular velocity At this time, the three-axis air floating platform is at risk of tipping over, and emergency risk avoidance control is required. Emergency risk avoidance control is performed on the three-axis air floating platform, specifically, the actuator of the three-axis air floating platform is controlled to stop running, the limit protection device of the three-axis air floating platform is started, and the air floating test device is supported by the limit protection device.

[0075] S7, check whether the three-axis air bearing platform simulation test system has completed the simulation test task, if yes, execute step S8, otherwise, return to step S2;

[0076] S8, the three-axis air-floating platform simulation test system ends the simulation test and outputs the simulation test result. If the three-axis air-floating platform is subjected to emergency avoidance control, the actuator of the three-axis air-floating platform stops running, and the air-floating test device is supported by the limit protection device of the three-axis air-floating platform. The simulation test result at this time is a test failure.

[0077] Specifically, the first angle is preset , Second Angle and the first angular velocity And set the safety mode of the three-axis air bearing platform:

[0078] When the real-time angle of the three-axis air bearing table Located at 0~ Within the range, that is When the three-axis air-floating platform is in normal working state, the simulation test can be carried out normally in this state;

[0079] When the real-time angle of the three-axis air bearing table lie in ~ Within the range, that is When the first angular velocity and the real-time angular velocity of the three-axis air bearing stage Further judgment:

[0080] If the real-time angular velocity of the three-axis air-floating platform Located at 0~ Within the range, that is When the three-axis air-floating platform is in normal risk avoidance control, its tilt angle is between 0 and range, and then continue the simulation test;

[0081] If the real-time angular velocity of the three-axis air-floating platform Greater than or equal to ,Right now When the error is detected, it has exceeded the range that can be corrected by normal risk avoidance, and the three-axis air floating platform can only be controlled by emergency risk avoidance;

[0082] When the real-time angle of the three-axis air bearing platform is ~ Within the range, that is When the three-axis air floating platform is in an emergency avoidance state, in which the three-axis air floating platform is at risk of tipping over, and emergency avoidance control is required to end the test. is the limit tilt angle of the three-axis air bearing table.

[0083] In another embodiment, see Figure 2 , Figures 4 to 8 A three-axis air-floating platform, using any of the above-mentioned anti-dumping control methods to perform anti-dumping control during a simulation test, the three-axis air-floating platform comprising:

[0084] The air flotation test device 1 is used to carry an external test piece for air flotation test, including a support connection platform 11, a control unit 12 arranged on the outer side of the support connection platform 11, an air flotation ball 13 arranged at the center of the bottom surface of the support connection platform 11, and a table counterweight placed on the support connection platform 11. The external test piece is fixedly mounted on the upper surface of the support connection platform 11. The control unit 12 includes a reaction flywheel, which includes an X-axis disturbance flywheel, a Y-axis disturbance flywheel, and a Z-axis disturbance flywheel, and is used to adjust and control the posture of the air flotation test device 1. The air flotation ball 13 includes a flat plate portion 131 and a spherical portion 132 with the flat plate portion 131;

[0085] The air-floating support device 2 is used to support the air-floating test device 1, and includes a support frame 21. The top surface of the support frame 21 is provided with an air-floating seat 211. The air-floating seat 211 is provided with a spherical groove. The bottom surface of the supporting connection platform 11 is movably connected to the air-floating seat 211 of the support frame 21 through the spherical portion 132 on the air-floating ball 13.

[0086] The cold air thrust unit 3 is mounted above the supporting connection platform 11, and its center of gravity coincides with the center of the air floating ball 13, and is used to realize that the air floating test device 1 is balanced and set on the air floating support device 2. The cold air thrust unit 3 provides a power source of large torque, and does not affect the center of gravity position of the entire three-axis air floating platform in the case of jetting;

[0087] The limit protection device 4 includes a support protection component 41 and an air flotation protection component 42. The support protection component 41 is mounted on the support frame 21 and can move vertically along the main body of the support frame 21. The air flotation protection component 42 is fixedly connected to the edge of the bottom surface of the support connection platform 11 and can move with the support connection platform 11. The support protection component 41 can abut against the air flotation protection component 42 to support the air flotation test device 1, thereby realizing emergency risk avoidance control of the three-axis air flotation platform.

[0088] Further, see Figure 8 The support and protection assembly 41 includes a support plate 411, a cylinder fixing seat 412 and a thrust cylinder 413. The cylinder fixing seat 412 is sleeved and installed on the top of the support frame 21. The thrust cylinder 413 is installed on the cylinder fixing seat 412. The support plate 411 is installed on the top of the thrust cylinder 413. The air flotation protection assembly 42 includes a protection plate 421. The protection plate 421 is fixedly connected to the lower surface of the support connection platform 11. The support plate 411 is annular, and the protection plate 421 is annular. If the real-time angle of the three-axis air flotation table is greater than or equal to the second angle Or the real-time angular velocity is greater than or equal to the first angular velocity When the three-axis air-floating platform needs to be emergency-avoided, the thrust cylinder 413 is activated, and the support plate 411 is pushed vertically upward along the support frame 21 by the thrust cylinder 413, so that the support plate 411 and the protective plate 421 are in contact with each other to support the air-floating test device 1, thereby realizing the emergency-avoided control of the three-axis air-floating platform. In addition, when the three-axis air-floating platform is in a shutdown state, the support protection component 41 and the air-floating protection component 42 are also in contact with each other in the above-mentioned manner to support the air-floating test device 1, that is, after the three-axis air-floating platform cuts off the air source, the limit protection device 4 can also provide non-contact and non-friction protection between the air-floating ball 13 and the air-floating seat 211.

[0089] Further, see Figure 4 The control unit 12 further includes a leveling component, which is used to level the air flotation test device 1. The leveling component includes:

[0090] A plurality of tilting brackets 121 are arranged in a circular array around the center line of the support connection platform 11 on the edge of the support connection platform 11; a plurality of coarse leveling modules 122 are respectively installed on the plurality of tilting brackets 121 in a tilted manner and on one side away from the support connection platform 11; a plurality of fine leveling modules 123 are equidistantly arranged at the bottom of the support connection platform 11; a plurality of fine leveling modules 124 are respectively installed on the plurality of tilting brackets 121 in a tilted manner. The tilt angle between the tilting bracket 121 and the support connection platform 11 is 30°-60°, which can be selected according to space requirements and leveling methods.

[0091] The coarse leveling module 122 and the fine leveling module 124 are installed in an inclined manner to adjust the center of gravity of the three directions of XYZ in the spatial coordinate system, so that the center of gravity is infinitely close to the center of the air-floating ball 13, so that the state of the air-floating test device 1 is infinitely close to the working state in space, which is convenient for subsequent space simulation experiments. The relative position relationship between the three axes of XYZ and the present invention is detailed in Figure 4 shown.

[0092] It should be noted that when the three-axis air floating table is under normal risk avoidance control, the leveling component can also be used to adjust the angle of the three-axis air floating table so that the real-time angle of the three-axis air floating table is smaller than the preset first angle. However, after the real-time angle is adjusted using the leveling component, the current round of simulation test cannot be continued.

[0093] As a further improvement to this embodiment, see Figure 3 , Fig. 9 and Fig.10 ,in, Figure 3 It is a longitudinal section view of the three-axis air-floating platform in an extreme state for emergency avoidance; Fig. 9 for Figure 3The partially enlarged schematic diagram of the portion A in the middle is a schematic diagram of the operation of the lateral limit buffer 52; Fig.10 for Figure 3 The partially enlarged schematic diagram at point B is a schematic diagram of the operation of the vertical limit buffer 51 .

[0094] The three-axis air-floating platform also includes a limit buffer device 5, which includes a vertical limit buffer 51 and a horizontal limit buffer 52. The vertical limit buffer 51 is arranged along the circumference of the support frame 21 and is located above the cylinder fixing seat 412, and is used for buffering the contact between the support frame 21 and the lower edge of the supporting connection platform 11 when the three-axis air-floating platform deflects at a large angle. The horizontal limit buffer 52 is in the shape of a hollow cylinder and is sleeved on the circumference of the air-floating seat 211, and is used for buffering the contact between the flat plate portion 131 of the air-floating ball 13 and the upper edge of the air-floating seat 211 when the three-axis air-floating platform deflects at a large angle. The limit buffer device 5 is specifically a soft elastic member, which can be made of rubber, silicone, etc., and can play a buffering role when the three-axis air-floating platform deflects at a large angle, further strengthening the protective function.

[0095] As a further improvement of this embodiment, the three-axis air floating platform also includes an anti-fall device 6, which includes a protection frame 61 and multiple protection pads 62. The protection frame 61 is arranged around the air floating support device 2 and is located below it. The multiple protection pads 62 are spliced ​​and placed on the protection frame 61.

[0096] See also Figure 2 and Fig.11 The air-floating support device 2 also includes a load-bearing platform 22 and a support foot frame 23. The load-bearing platform 22 is fixedly mounted at the bottom of the support frame 21. The support foot frame 23 is mounted below the load-bearing platform 22 to support the load-bearing platform 22. The anti-fall device 6 includes a protection frame 61 and a plurality of protection pads 62. The protection frame 61 includes a plurality of movable supports that can be spliced ​​together. The plurality of movable supports that can be spliced ​​together are arranged around the support foot frame 23. The plurality of protection pads 62 are spliced ​​together and placed on the protection frame 61. Through the above design, when the tilt angle of the three-axis air-floating platform reaches or exceeds the limit tilt angle and falls over, further buffering protection can be provided for the external test piece or the control unit 12 mounted on the support connection platform 11 and the air-floating test device 1.

[0097] The above-mentioned three-axis air floating platform and its simulation test anti-dumping control method are provided with multiple anti-dumping protection devices in the three-axis air floating platform. The first angle, the second angle and the first angular velocity are preset in the anti-dumping control method, and the real-time angle and the real-time angular velocity of the three-axis air floating platform during the execution of the simulation test task are collected, and the real-time angle and the real-time angular velocity are respectively compared with the preset angle and angular velocity. When it is judged that the three-axis air floating platform has the risk of dumping, a control method combining emergency avoidance control and normal avoidance control is adopted to perform avoidance operation. The working reliability of the three-axis air floating platform can be further improved by combining mechanical protection and software control protection.

[0098] The above is a detailed introduction to a three-axis air-floating platform and a simulation test anti-dumping control method thereof provided by the present invention. This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the core idea of ​​the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, the present invention can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A three-axis air-floating platform simulation test anti-dumping control method, characterized in that: The method comprises the following steps: S1, preset a first angle, a second angle and a first angular velocity, mount the external object to be tested on the three-axis air bearing platform, initialize the three-axis air bearing platform, and set the simulation mode and parameters; S2. The three-axis air floating platform performs a simulation test task. The air floating test device of the three-axis air floating platform collects the posture information of the three-axis air floating platform during the simulation test. The posture information includes the real-time angle and real-time angular velocity of the three-axis air floating platform. S3, comparing the real-time angle of the three-axis air-floating platform with the first angle, if the real-time angle is smaller than the first angle, executing step S7, otherwise, executing step S4; S4, comparing the real-time angle of the three-axis air-floating platform with the second angle, and comparing the real-time angular velocity of the three-axis air-floating platform with the first angular velocity. If the real-time angle is less than the second angle and the real-time angular velocity is less than the first angular velocity, executing step S5; otherwise, if the real-time angle is greater than or equal to the second angle or the real-time angular velocity is greater than or equal to the first angular velocity, executing step S6; S5, perform normal risk avoidance control on the three-axis air floating platform and execute step S7; S6, perform emergency risk avoidance control on the three-axis air floating platform, and execute step S8; S7, check whether the three-axis air bearing platform simulation test system has completed the simulation test task, if yes, execute step S8, otherwise, return to step S2; S8. The three-axis air bearing platform simulation test system ends the simulation test and outputs the simulation test results.

2. The anti-dumping control method for the three-axis air-floating platform simulation test as claimed in claim 1, characterized in that: The calculation formula of the first angular velocity in S1 is: ； In the formula, is the preset first angular velocity, is the maximum output torque of the three-axis air bearing actuator, is the moment of inertia of the three-axis air bearing platform, is the preset first angle, The second preset angle.

3. The anti-dumping control method for the three-axis air-floating platform simulation test as claimed in claim 2, characterized in that: In S5, the three-axis air floating platform is normally controlled to avoid danger. Specifically, the real-time angle of the three-axis air floating platform is adjusted by outputting a control torque through the actuator of the three-axis air floating platform, so that the real-time angle is smaller than the preset first angle.

4. The anti-dumping control method for the three-axis air-floating platform simulation test as claimed in claim 3, characterized in that: The actuator includes a cold air thrust unit and a reaction flywheel. The actuator of the three-axis air bearing platform outputs a control torque to adjust the real-time angle of the three-axis air bearing platform so that the real-time angle is less than the preset first angle, which specifically includes: S51, presetting a second angular velocity, wherein the second angular velocity is less than the first angular velocity; S52, comparing the real-time angular velocity of the three-axis air-floating platform with the second angular velocity, if the real-time angular velocity of the three-axis air-floating platform is less than or equal to the second angular velocity, executing step S53, otherwise, executing step S54; S53, adjusting the real-time angle of the three-axis air bearing platform by outputting a torque of a reaction flywheel; S54, adjusting the real-time angle of the three-axis air-floating platform by outputting torques through the cold air thrust unit and the reaction flywheel respectively; S55, obtaining the real-time angle of the three-axis air-floating platform, comparing the real-time angle with the first angle, if the real-time angle is greater than or equal to the first angle, returning to step S52, otherwise, ending the normal risk avoidance control.

5. The anti-dumping control method for the three-axis air-floating platform simulation test as claimed in claim 1, characterized in that: In S6, the three-axis air floating platform is subjected to emergency risk avoidance control, specifically, the actuator of the three-axis air floating platform is controlled to stop running, the limit protection device of the three-axis air floating platform is started, and the air floating test device is supported by the limit protection device.

6. A three-axis air-floating platform, using the three-axis air-floating platform simulation test anti-dumping control method as claimed in any one of claims 1 to 5 to perform anti-dumping control during a simulation test, characterized in that: The three-axis air bearing platform comprises: An air flotation test device (1) is used to carry an external test piece for air flotation testing, comprising a supporting connection platform (11), a control unit (12) arranged on the outer side of the supporting connection platform (11), an air flotation ball (13) arranged at the center of the bottom surface of the supporting connection platform (11), and a counterweight block placed on the supporting connection platform (11); the external test piece is fixedly mounted on the upper surface of the supporting connection platform (11); the control unit (12) comprises a reaction flywheel for adjusting and controlling the posture of the air flotation test device (1); and the air flotation ball (13) comprises a flat plate portion (131) and a spherical portion (132); An air-floating support device (2) is used to support an air-floating test device (1), comprising a support frame (21), the top surface of the support frame (21) being provided with an air-floating seat (211), the air-floating seat (211) being provided with a spherical groove, and the bottom surface of the supporting connection platform (11) being movably connected to the air-floating seat (211) of the support frame (21) via a spherical portion (132) on an air-floating ball (13); The cold air thrust unit (3) is mounted above the supporting connection platform (11), and its center of gravity coincides with the center of the air floating ball (13), so as to realize the balanced setting of the air floating test device (1) on the air floating support device (2); The position limiting protection device (4) comprises a support protection component (41) and an air flotation protection component (42); the support protection component (41) is sleeved on the support frame (21) and can move vertically along the support frame (21) body; the air flotation protection component (42) is fixedly connected to the edge of the bottom surface of the support connection platform (11) and can move along with the support connection platform (11); the support protection component (41) can abut against the air flotation protection component (42) to support the air flotation test device (1), thereby realizing emergency risk avoidance control of the three-axis air flotation platform.

7. The three-axis air bearing platform according to claim 6, characterized in that: The support protection assembly (41) comprises a support plate (411), a cylinder fixing seat (412) and a thrust cylinder (413); the cylinder fixing seat (412) is sleeved and mounted on the top of the support frame (21); the thrust cylinder (413) is mounted on the cylinder fixing seat (412); the support plate (411) is mounted on the top of the thrust cylinder (413); the air floating protection assembly (42) comprises a protection plate (421); the protection plate (421) is fixedly connected to the lower surface of the support connection platform (11); the support plate (411) can be pushed by the thrust cylinder (413) to move vertically along the support frame (21), so that the support plate (411) and the protection plate (421) are abutted to support the air floating test device (1), thereby realizing emergency avoidance control of the three-axis air floating platform.

8. The three-axis air bearing platform according to claim 7, characterized in that: The control unit (12) further comprises a leveling component for leveling the air flotation test device (1), the leveling component comprising: a plurality of inclined brackets (121) arranged in a circular array around the center line of the support connection platform (11) at the edge of the support connection platform (11); a plurality of coarse leveling modules (122) respectively mounted on the plurality of inclined brackets (121) in an inclined manner and on a side away from the support connection platform (11); a plurality of fine leveling modules (123) arranged equidistantly at the bottom of the support connection platform (11); and a plurality of fine leveling modules (124) respectively mounted on the plurality of inclined brackets (121) in an inclined manner.

9. The three-axis air bearing platform according to claim 8, characterized in that: The device also comprises a limit buffer device (5), the limit buffer device (5) comprising a vertical limit buffer member (51) and a horizontal limit buffer member (52). The vertical limit buffer member (51) is arranged along the circumference of the support frame (21) and is located above the cylinder fixing seat (412), and is used for buffering the contact between the support frame (21) and the lower edge of the supporting connection platform (11) when the three-axis air floating platform deflects at a large angle. The horizontal limit buffer member (52) is in the shape of a hollow cylinder and is sleeved on the circumference of the air floating seat (211). It is used for buffering the contact between the flat plate portion (131) of the air floating ball (13) and the upper edge of the air floating seat (211) when the three-axis air floating platform deflects at a large angle.

10. The three-axis air bearing platform according to claim 9, characterized in that: It also includes an anti-fall device (6), the anti-fall device (6) including a protection frame (61) and a plurality of protection pads (62), the protection frame (61) being arranged around the air-floating support device (2) and located below it, and the plurality of protection pads (62) being placed on the protection frame after being spliced ​​together.

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