Six-degree-of-freedom intelligent following air bearing table

Abstract

The invention relates to a six-degree-of-freedom intelligent following air bearing table, and belongs to the field of spaceflight mechanism ground tests. And a combined bracket of the intelligent following subsystem is utilized to realize six-degree-of-freedom movement of the tail end of the large space multi-joint mechanism. The arc-shaped guide rails are connected with the supporting rollers, so that the task load can do pitching motion on the vertical plane. Air feet are installed below the combined bracket body, and therefore three-degree-of-freedom movement on an air floating flat plate can be achieved. And the vertical movement of the air floating platform and the combined bracket is realized through the air floating guide rail. The supporting rollers, the arc-shaped guide rails, the air feet and the air floating guide rails jointly achieve six-degree-of-freedom movement of task loads.

Description

Technical Field

[0001] This invention relates to a six-degree-of-freedom intelligent following air-bearing platform, belonging to the field of ground testing for aerospace institutions. Background Technology

[0002] With the continuous development of aerospace technology, the application of large-scale space multi-joint mechanisms is becoming increasingly widespread. These mechanisms are enormous in size, have complex end-effector movements, and incur high launch costs, thus requiring pre-launch microgravity simulation tests on the ground. These tests need to accurately simulate the mechanical environment in space, allowing the space multi-joint mechanism to mimic its on-orbit motion under ground conditions. Ground microgravity tests typically employ a support method, using air-bearing fixtures to levitate the space mechanism and balance gravity. To meet the requirements of three-dimensional motion and high-precision, high-dynamic, and heavy-load ground microgravity testing of large-scale space multi-joint mechanisms, large-area air-bearing platforms are constructed in ground-based laboratories. This is extremely costly, and the seams of the assembled air-bearing platforms are difficult to machine, easily leading to jamming and affecting the motion of the large-scale space multi-joint mechanism. Furthermore, the complex design of the air-bearing fixtures, far exceeding the mass of the space mechanism, poses safety hazards and introduces significant additional resistance and torque into the motion of the space multi-joint mechanism, affecting the accuracy of the ground microgravity tests.

[0003] Therefore, it is necessary to design a large air-floating platform that does not rely on difficult processing and can operate on relatively simple self-leveling surfaces, satisfying the six-degree-of-freedom motion of the end effector of a large spatial multi-joint mechanism, in order to solve the above problems.

[0004] The existing technology has the following problems: Ground-based microgravity testing methods for large-scale spatial multi-joint motion mechanisms can be broadly divided into two types: suspension and support. The suspension method uses retractable slings to suspend the large spatial multi-joint mechanism to accommodate the three-dimensional spatial motion of the structure. However, its application to large-scale spatial multi-joint mechanisms requires the construction of a massive magnetic platform and corresponding supporting equipment, resulting in high costs and issues with the accuracy of test results. The support method requires a large-area, high-precision air-floating platform for the air-floating fixture. The large-scale, highly flat air-floating platform, assembled from multiple pieces, places extremely stringent requirements on processing and installation. Platform debugging is difficult, and there is a risk of jamming and friction at the joints of the air-floating platform. This leads to significant additional frictional resistance and torque at the joints of the large-scale spatial multi-joint motion mechanism, which is detrimental to obtaining high-precision and accurate results from ground-based tests. Summary of the Invention

[0005] This invention designs an air-floating platform that does not rely on difficult-to-process fabrication surfaces, enabling it to operate on relatively simple self-leveling surfaces and satisfy the six-degree-of-freedom motion requirements of the end effector of large-scale spatial multi-joint mechanisms. Regarding usage conditions, traditional air-floating vehicles and fixtures require large-area marble air-floating platforms, resulting in high costs, difficult platform debugging, and limited applicability. The horizontal adjustment subsystem of the proposed six-degree-of-freedom intelligent following air-floating platform reduces its dependence on marble air-floating platforms by leveling the platform plane in real time, allowing the system to operate on self-leveling surfaces. In terms of hardware, this invention achieves three-dimensional six-degree-of-freedom motion of the end effector of large-scale spatial multi-joint mechanisms through the rational arrangement of multiple subsystems, fully meeting the requirements of complex ground-based testing of large-scale spatial multi-joint mechanisms.

[0006] The technical solution of this invention is: A six-degree-of-freedom intelligent following air-float platform, the air-float platform includes a gravity unloading subsystem, a position tracking subsystem, a measurement and control subsystem and a horizontal adjustment subsystem; The gravity unloading subsystem includes: four sets of large fixed pulleys (1-1), four sets of small fixed pulleys (1-2), ropes (1-3), eight air-floating sliders (1-4), air-floating plate (1-5), air-floating guide rail (1-6), column (1-7), and counterweight box (1-8). The small fixed pulley (1-2) and the large fixed pulley (1-1) are fixed on both sides of the top of the column (1-7); The counterweight box (1-8) is connected to the small fixed pulley (1-2) and the large fixed pulley (1-1) in sequence by rope (1-3) through the lifting ring installed at the top, thereby realizing the linkage between the counterweight box (1-8) and the combined bracket (1-9); The air-bearing guide rail (1-6) is fixedly installed on the column (1-7) in the vertical direction; The eight air-floating sliders (1-4) are arranged in a front-four-back layout on both sides of the air-floating guide rail (1-6), thereby enabling the combined bracket (1-9) to move up and down along the air-floating guide rail (1-6) under the action of the eight air-floating sliders (1-4). The air flotation plate (1-5) is vertically installed on the air flotation guide rail (1-6), and the combined bracket (1-9) is placed on the air flotation plate (1-5) through the air foot; The gravity unloading subsystem uses small fixed pulleys (1-2) and large fixed pulleys (1-1) to link the counterweight box (1-8) and the air-floating plate (1-5), unloading the gravity of the air-floating plate (1-5) and the combined bracket (1-9). The air-floating slider (1-4) and the air-floating guide rail (1-6) constrain the vertical frictionless movement of the air-floating plate (1-5), and the unloading force value is obtained through the measurement and control subsystem and the force sensor (3-6). The position tracking subsystem includes: three laser sensors (2-3), a combined bracket (1-9), a Mecanum drive module (1-10), an air-bearing support platform (1-11), and a mission payload (1-12); Three laser sensors (2-3) are sequentially mounted on an air-floating plate (1-5); The position tracking subsystem realizes the position movement of the combined bracket (1-9) on the air-floating plate (1-5) through the air foot of the combined bracket (1-9), measures the displacement deviation through the staggered arrangement of laser sensors (2-3), and drives the six-degree-of-freedom intelligent following air-floating platform to follow the movement of the mission load (1-12) through the Mecanum drive module (1-10). The combined bracket (1-9) includes an air float plate limiting block (3-1), four support rollers (3-2), an arc-shaped guide rail (3-3), four laser sensor light shields (3-4), an air foot (3-5), and a force sensor (3-6); The air flotation plate limiting block (3-1) is arranged below the combined bracket (1-9) to prevent the combined bracket (1-9) from tipping over; Four support rollers (3-2) are symmetrically installed on the combined bracket (1-9); Four laser sensor light shields (3-4) are installed perpendicularly to each other around the combined bracket (1-9); The support roller (3-2) is used to support the task load (1-12), so that the task load (1-12) rotates on the support roller (3-2) about its own axis; The arc-shaped guide rail (3-3) is connected to the support roller (3-2), enabling the task load (1-12) to pitch in the vertical plane; The arc-shaped guide rail (3-3) is fixedly connected to the combined bracket (1-9), and the lower part of the arc-shaped guide rail (3-3) is fixedly connected to the force sensor (3-6), which is used to measure the unloading force value; An air foot (3-5) is installed below the combined bracket (1-9), which enables three-degree-of-freedom motion on the air-floating plate (1-5); The vertical displacement of the air-floating plate (1-5) is achieved by using the air-floating guide rail (1-6) and the air-floating slider (1-4); The support roller (3-2), the arc-shaped guide rail (3-3), the air foot (3-5), and the air-bearing guide rail (1-6) together realize the six-degree-of-freedom motion of the task load (1-12); Four Mecanum drive modules (1-10) are symmetrically installed below the air-bearing support platform (1-11); The gravity unloading subsystem is installed above the air-floating support platform (1-11); The measurement and control subsystem includes a host computer (human-machine interaction module) and a slave computer (1-15) (control module); the slave computer (1-15) includes a fully packaged encoder, AD acquisition board, motor drive board, and STM32 control board. The measurement and control subsystem obtains the distance between the three laser sensors (2-3) and the laser sensor shielding plate (3-4), and then calculates and converts the translation and rotation of the object in the plane into the drive signal of the Mecanum drive module, thereby driving the six-degree-of-freedom intelligent following air-bearing platform to move. The horizontal adjustment subsystem includes: lifting motor (4-1), lifting screw (4-2), suspension support plate (4-3), suspension support optical axis (4-4), Z-beam (4-5), level (2-1), inertial measurement element (2-2), lidar (1-13), and laser displacement sensor (1-14); A level (2-1) and an inertial measurement element (2-2) are mounted on an air-floating plate (1-5) to measure the tilt angle of the air-floating plate (1-5); The lidar (1-13) is installed above the column (1-7). The lidar (1-13) measures the position of the six-degree-of-freedom intelligent following air-floating platform in the field, and the laser displacement sensors (1-14) arranged at the four corners of the air-floating support platform (1-11) measure the tilt angle of the air-floating support platform (1-11). The lifting motor (4-1) is fixed to the Z-beam (4-5); The lifting screw (4-2) is fixed to the drive end of the lifting motor (4-1); The lifting motor (4-1) can control the suspension support plate (4-3) to move up and down along the suspension support optical axis (4-4) by driving the lifting screw (4-2). During the six-degree-of-freedom intelligent following of the air-floating platform, it can servo the ground height error in real time, so that the air-floating support platform (1-11) can be kept in a horizontal state. As a preferred option, the counterweight in the counterweight box (1-8) is selected to use multiple thin steel plates. By increasing or decreasing the number of thin steel plates, the mass of one end of the combined bracket (1-9) is balanced, thereby improving the ability of the six-degree-of-freedom intelligent following air-floating platform to adapt to different space deployment mechanisms. Preferably, the air-bearing guide rail (1-6), air-bearing slider (1-4), air foot (3-5), and support roller (3-2) should be equipped with dustproof devices; A level is installed on the air-floating plate (1-5) to measure the tilt angle of the air-floating plate (1-5). A lidar (1-13) is installed on the top of the air-floating platform to measure the position of the six-degree-of-freedom intelligent following air-floating platform in the field. The tilt angle of the air-floating support platform (1-11) is measured by laser displacement sensors (1-14) arranged at the four corners of the air-floating support platform (1-11). By combining the site topography information and the real-time measured tilt angle of the air-floating plate (1-5), the air-floating plate (1-5) is kept in a horizontal state by adjusting the distance between the four corners of the air-floating support platform (1-11) and the ground, thereby improving the site adaptability and avoiding the test piece fixed to the space unfolding mechanism from shifting under the action of gravity due to the combined bracket (1-9) not being in a horizontal state, which would increase the additional resistance and additional resistance torque during the test and reduce the unloading efficiency of the six-degree-of-freedom intelligent following air-floating platform. The air-floating support platform (1-11) is leveled and raised and lowered by lifting motor (4-1), lifting screw (4-2), etc. The working process of a six-degree-of-freedom self-leveling air-floating vehicle for large-scale space multi-joint mechanisms disclosed in this invention is as follows.

[0007] In servo control mode, the combined bracket (1-9) and air-bearing guide rail (1-6) are opened to supply air, and the six-degree-of-freedom intelligent following air-bearing platform actively follows the movement of the large-scale spatial multi-joint mechanism; When the large space multi-joint mechanism moves vertically, the number of counterweights in the counterweight box (1-8) is adjusted to balance the friction of the air-bearing guide rail (1-6), and the position of the air-bearing plate (1-5) is adjusted to achieve zero-gravity test of the large space deployment mechanism; The horizontal adjustment is achieved by measuring the position of the six-degree-of-freedom intelligent following air-float platform using a lidar (1-13), measuring the ground height using a laser sensor (2-3), and measuring the tilt angle of the air-float platform (1-5) using an inertial measurement unit and a level installed on the air-float platform (1-5). The tilt angle of the air-float platform (1-5) is adjusted by the four corner lifting motors (4-1) of the air-float support platform (1-11), so that the six-degree-of-freedom intelligent following air-float platform can adapt to the self-leveling ground in real time and ensure that the air-float platform (1-5) is level.

[0008] Beneficial effects This invention discloses a six-degree-of-freedom intelligent following air-floating platform for large-scale spatial multi-joint mechanisms. Compared with existing air-floating tooling ground microgravity testing equipment, it offers more convenient usage conditions and more precise planar leveling capabilities, facilitating rapid and low-cost ground testing of large-scale spatial multi-joint mechanisms. This invention utilizes a Mecanum car chassis to follow the movement of the large-scale spatial multi-joint mechanism; it employs the synergistic action of a combined bracket, air-floating guide rails, fixed pulley blocks, and a counterweight box to achieve gravity unloading for vertical movement; it uses lidar, laser sensors, inertial measurement elements, and a level to measure the tilt angle of the air-floating platform; and it uses a lead screw and disc spring suspension to achieve Mecanum car chassis leveling. This allows the six-degree-of-freedom intelligent following air-floating platform to adapt to self-leveling surfaces, eliminating the need for constructing a large air-floating platform, reducing dependence on site conditions, and improving ease of use.

[0009] This invention discloses a six-degree-of-freedom intelligent following air-bearing platform for large-scale spatial multi-joint mechanisms. Utilizing a combined bracket of an intelligent following subsystem, it achieves six-degree-of-freedom end-effector motion for the large-scale spatial multi-joint mechanism. A curved guide rail connects to support rollers, allowing the task load to pitch in the vertical plane. An air foot installed below the combined bracket body enables three-degree-of-freedom motion on the air-bearing plate. The air-bearing guide rail enables vertical movement of the air-bearing platform and the combined bracket. The support rollers, curved guide rail, air foot, and air-bearing guide rail together achieve the six-degree-of-freedom motion of the task load.

[0010] This invention discloses a six-degree-of-freedom intelligent following air-floating platform for large-scale spatial multi-joint mechanisms. It eliminates the need for fabricating large marble air-floating platforms and utilizes an air-floating vehicle leveling subsystem, enabling ground deployment tests of large-scale spatial multi-joint mechanisms on self-leveling surfaces, thus reducing the cost of ground microgravity testing. A level and inertial measurement unit are installed on the air-floating plate to measure its tilt angle; a lidar mounted above the top support plate measures the position of the six-degree-of-freedom intelligent following air-floating platform in the field; and laser sensors positioned at the four corners of the air-floating support platform measure its tilt angle. By combining site topography information with the real-time measured tilt angle of the air-floating plate, the distance between the four corners of the air-floating support platform and the ground is adjusted to keep the air-floating plate level. This improves site adaptability and prevents the test piece fixed to the spatial deployment mechanism from shifting under the influence of gravity due to the combined bracket not being level, which would increase additional resistance and torque during the test and reduce the unloading efficiency of the six-degree-of-freedom intelligent following air-floating platform. This enables the six-degree-of-freedom intelligent following air-float platform to adapt to self-leveling surfaces, eliminating the need to install a flat air-float platform. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the gravity unloading subsystem; Figure 3 This is a schematic diagram of the combined bracket; Figure 4 This is a schematic diagram of an air-float support platform; Figure 5 This is a schematic diagram of the horizontal adjustment subsystem. Detailed Implementation

[0012] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0013] The six-degree-of-freedom intelligent following air-float platform of this invention comprises a gravity unloading subsystem, an intelligent following subsystem, a horizontal adjustment subsystem, and a measurement and control subsystem. The air-float support platform of the horizontal adjustment subsystem includes a vehicle platform, Mecanum wheels, a lifting mechanism, a lifting motor, a lidar, a level, an inertial measurement unit (IMU), and a laser displacement sensor. A level and IMU are simultaneously installed on the air-float plate to measure its tilt angle. A lidar is installed above the top support plate to measure the position of the six-degree-of-freedom intelligent following air-float platform in the field, and laser sensors positioned at the four corners of the platform measure its tilt angle. By combining the site topography information with the real-time measured tilt angle of the air-float platform, the distance between the four corners and the ground is adjusted to keep the air-float plate horizontal. This improves site adaptability and prevents the test piece fixed to the spatial deployment mechanism from shifting under the influence of gravity due to the combined bracket not being horizontal, thus avoiding increased additional resistance and torque during the test and reducing the unloading efficiency of the six-degree-of-freedom intelligent following air-float platform. The intelligent following subsystem's combined support frame includes support rollers, air feet, an arc-shaped guide rail, a force sensor, the combined support frame body, and a laser sensor. The support rollers directly support the load, allowing it to rotate around its own axis on the support rollers. The arc-shaped guide rail connects to the support rollers, enabling the load to pitch in a vertical plane. The arc-shaped guide rail is fixed to the combined support frame body and connected below to the force sensor to measure the unloading force. An air foot is installed below the combined support frame body, enabling three-degree-of-freedom motion on the air-floating plate. The support rollers, arc-shaped guide rail, air feet, and air-floating guide rail together achieve six-degree-of-freedom motion of the load. A laser sensor is installed inside the lower baffle to measure the deviation of the combined support frame's three-degree-of-freedom motion on the air-floating plate.

[0014] Example A six-degree-of-freedom intelligent following air-float platform, the air-float platform includes a gravity unloading subsystem, a position tracking subsystem, a measurement and control subsystem and a horizontal adjustment subsystem; The gravity unloading subsystem includes: four sets of large fixed pulleys (1-1), four sets of small fixed pulleys (1-2), ropes (1-3), eight air-floating sliders (1-4), air-floating plate (1-5), air-floating guide rail (1-6), column (1-7), and counterweight box (1-8). The small fixed pulley (1-2) and the large fixed pulley (1-1) are fixed on both sides of the top of the column (1-7); The counterweight box (1-8) is connected to the small fixed pulley (1-2) and the large fixed pulley (1-1) in sequence by rope (1-3) through the lifting ring installed at the top, thereby realizing the linkage between the counterweight box (1-8) and the combined bracket (1-9); The air-bearing guide rail (1-6) is fixedly installed on the column (1-7) in the vertical direction; The eight air-floating sliders (1-4) are arranged in a front-four-back layout on both sides of the air-floating guide rail (1-6), thereby enabling the combined bracket (1-9) to move up and down along the air-floating guide rail (1-6) under the action of the eight air-floating sliders (1-4). The air flotation plate (1-5) is vertically installed on the air flotation guide rail (1-6), and the combined bracket (1-9) is placed on the air flotation plate (1-5) through the air foot; The gravity unloading subsystem uses small fixed pulleys (1-2) and large fixed pulleys (1-1) to link the counterweight box (1-8) and the air-floating plate (1-5), unloading the gravity of the air-floating plate (1-5) and the combined bracket (1-9). The air-floating slider (1-4) and the air-floating guide rail (1-6) constrain the vertical frictionless movement of the air-floating plate (1-5), and the unloading force value is obtained through the measurement and control subsystem and the force sensor (3-6). The position tracking subsystem includes: three laser sensors (2-3), a combined bracket (1-9), a Mecanum drive module (1-10), an air-bearing support platform (1-11), and a mission payload (1-12); Three laser sensors (2-3) are sequentially mounted on an air-floating plate (1-5); The position tracking subsystem realizes the position movement of the combined bracket (1-9) on the air-floating plate (1-5) through the air foot of the combined bracket (1-9), measures the displacement deviation through the staggered arrangement of laser sensors (2-3), and drives the six-degree-of-freedom intelligent following air-floating platform to follow the movement of the mission load (1-12) through the Mecanum drive module (1-10). The combined bracket (1-9) includes an air float plate limiting block (3-1), four support rollers (3-2), an arc-shaped guide rail (3-3), four laser sensor light shields (3-4), an air foot (3-5), and a force sensor (3-6); The air flotation plate limiting block (3-1) is arranged below the combined bracket (1-9) to prevent the combined bracket (1-9) from tipping over; Four support rollers (3-2) are symmetrically installed on the combined bracket (1-9); Four laser sensor light shields (3-4) are installed perpendicularly to each other around the combined bracket (1-9); The support roller (3-2) is used to support the task load (1-12), so that the task load (1-12) rotates on the support roller (3-2) about its own axis; The arc-shaped guide rail (3-3) is connected to the support roller (3-2), enabling the task load (1-12) to pitch in the vertical plane; The arc-shaped guide rail (3-3) is fixedly connected to the combined bracket (1-9), and the lower part of the arc-shaped guide rail (3-3) is fixedly connected to the force sensor (3-6), which is used to measure the unloading force value; An air foot (3-5) is installed below the combined bracket (1-9), which enables three-degree-of-freedom motion on the air-floating plate (1-5); The vertical displacement of the air-floating plate (1-5) is achieved by using the air-floating guide rail (1-6) and the air-floating slider (1-4); The support roller (3-2), the arc-shaped guide rail (3-3), the air foot (3-5), and the air-bearing guide rail (1-6) together realize the six-degree-of-freedom motion of the task load (1-12); Four Mecanum drive modules (1-10) are symmetrically installed below the air-bearing support platform (1-11); The gravity unloading subsystem is installed above the air-floating support platform (1-11); The measurement and control subsystem includes a host computer (human-machine interaction module) and a slave computer (1-15) (control module); the slave computer (1-15) includes a fully packaged encoder, AD acquisition board, motor drive board, and STM32 control board. The measurement and control subsystem obtains the distance between the three laser sensors (2-3) and the laser sensor shielding plate (3-4), and then calculates and converts the translation and rotation of the object in the plane into the drive signal of the Mecanum drive module, thereby driving the six-degree-of-freedom intelligent following air-bearing platform to move. The horizontal adjustment subsystem includes: lifting motor (4-1), lifting screw (4-2), suspension support plate (4-3), suspension support optical axis (4-4), Z-beam (4-5), level (2-1), inertial measurement element (2-2), lidar (1-13), and laser displacement sensor (1-14); A level (2-1) and an inertial measurement element (2-2) are mounted on an air-floating plate (1-5) to measure the tilt angle of the air-floating plate (1-5); The lidar (1-13) is installed above the column (1-7). The lidar (1-13) measures the position of the six-degree-of-freedom intelligent following air-floating platform in the field, and the laser displacement sensors (1-14) arranged at the four corners of the air-floating support platform (1-11) measure the tilt angle of the air-floating support platform (1-11). The lifting motor (4-1) is fixed to the Z-beam (4-5); The lifting screw (4-2) is fixed to the drive end of the lifting motor (4-1); The lifting motor (4-1) can control the suspension support plate (4-3) to move up and down along the suspension support optical axis (4-4) by driving the lifting screw (4-2). During the six-degree-of-freedom intelligent following of the air-floating platform, it can servo the ground height error in real time, so that the air-floating support platform (1-11) can be kept in a horizontal state. As a preferred option, the counterweight in the counterweight box (1-8) is selected to use multiple thin steel plates. By increasing or decreasing the number of thin steel plates, the mass of one end of the combined bracket (1-9) is balanced, thereby improving the ability of the six-degree-of-freedom intelligent following air-floating platform to adapt to different space deployment mechanisms. Preferably, the air-bearing guide rail (1-6), air-bearing slider (1-4), air foot (3-5), and support roller (3-2) should be equipped with dustproof devices; A level is installed on the air-floating plate (1-5) to measure the tilt angle of the air-floating plate (1-5). A lidar (1-13) is installed on the top of the air-floating platform to measure the position of the six-degree-of-freedom intelligent following air-floating platform in the field. The tilt angle of the air-floating support platform (1-11) is measured by laser displacement sensors (1-14) arranged at the four corners of the air-floating support platform (1-11). By combining the site topography information and the real-time measured tilt angle of the air-floating plate (1-5), the air-floating plate (1-5) is kept in a horizontal state by adjusting the distance between the four corners of the air-floating support platform (1-11) and the ground, thereby improving the site adaptability and avoiding the test piece fixed to the space unfolding mechanism from shifting under the action of gravity due to the combined bracket (1-9) not being in a horizontal state, which would increase the additional resistance and additional resistance torque during the test and reduce the unloading efficiency of the six-degree-of-freedom intelligent following air-floating platform. The air-floating support platform (1-11) is leveled and raised and lowered by lifting motor (4-1), lifting screw (4-2), etc. The working process of a six-degree-of-freedom self-leveling air-floating vehicle for large-scale space multi-joint mechanisms disclosed in this invention is as follows.

[0015] In servo control mode, the combined bracket (1-9) and air-bearing guide rail (1-6) are opened to supply air, and the six-degree-of-freedom intelligent following air-bearing platform actively follows the movement of the large-scale spatial multi-joint mechanism; When the large space multi-joint mechanism moves vertically, the number of counterweights in the counterweight box (1-8) is adjusted to balance the friction of the air-bearing guide rail (1-6), and the position of the air-bearing plate (1-5) is adjusted to achieve zero-gravity test of the large space deployment mechanism; The horizontal adjustment is achieved by measuring the position of the six-degree-of-freedom intelligent following air-float platform using a lidar (1-13), measuring the ground height using a laser sensor (2-3), and measuring the tilt angle of the air-float platform (1-5) using an inertial measurement unit and a level installed on the air-float platform (1-5). The tilt angle of the air-float platform (1-5) is adjusted by the four corner lifting motors (4-1) of the air-float support platform (1-11), so that the six-degree-of-freedom intelligent following air-float platform can adapt to the self-leveling ground in real time and ensure that the air-float platform (1-5) is level.

[0016] In summary, the above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A six-degree-of-freedom intelligent following air-bearing platform, characterized in that: The air-floating platform includes a gravity unloading subsystem, a position tracking subsystem, a measurement and control subsystem, and a level adjustment subsystem; The gravity unloading subsystem includes four sets of large fixed pulleys (1-1), four sets of small fixed pulleys (1-2), ropes (1-3), eight air-bearing sliders (1-4), air-bearing flat plates (1-5), air-bearing guide rails (1-6), columns (1-7), and counterweight boxes (1-8). The position tracking subsystem includes: three laser sensors (2-3), a combined bracket (1-9), a Mecanum drive module (1-10), an air-bearing support platform (1-11), and a mission payload (1-12); The horizontal adjustment subsystem includes: lifting motor (4-1), lifting screw (4-2), suspension support plate (4-3), suspension support optical axis (4-4), Z-beam (4-5), level (2-1), inertial measurement element (2-2), lidar (1-13), and laser displacement sensor (1-14).

2. The six-degree-of-freedom intelligent following air-bearing platform according to claim 1, characterized in that: The small fixed pulley (1-2) and the large fixed pulley (1-1) are fixed on both sides of the top of the column (1-7); The counterweight box (1-8) is connected to the small fixed pulley (1-2) and the large fixed pulley (1-1) in sequence by rope (1-3) through the lifting ring installed at the top, thereby realizing the linkage between the counterweight box (1-8) and the combined bracket (1-9); The air-bearing guide rail (1-6) is fixedly installed on the column (1-7) in the vertical direction; The eight air-floating sliders (1-4) are arranged in a front-four-back layout on both sides of the air-floating guide rail (1-6), thereby enabling the combined bracket (1-9) to move up and down along the air-floating guide rail (1-6) under the action of the eight air-floating sliders (1-4). The air flotation plate (1-5) is vertically installed on the air flotation guide rail (1-6), and the combined bracket (1-9) is placed on the air flotation plate (1-5) through the air foot.

3. The six-degree-of-freedom intelligent following air-bearing platform according to claim 1, characterized in that: The gravity unloading subsystem uses small fixed pulleys (1-2) and large fixed pulleys (1-1) to link the counterweight box (1-8) and the air-floating plate (1-5), unloading the gravity of the air-floating plate (1-5) and the combined bracket (1-9). The air-floating slider (1-4) and the air-floating guide rail (1-6) constrain the vertical frictionless movement of the air-floating plate (1-5), and the unloading force value is obtained through the measurement and control subsystem and the force sensor (3-6).

4. The six-degree-of-freedom intelligent following air-bearing platform according to claim 1, characterized in that: Three laser sensors (2-3) are sequentially mounted on an air-floating plate (1-5); The position tracking subsystem moves the combined bracket (1-9) on the air-floating plate (1-5) by using the air foot of the combined bracket (1-9), measures the displacement deviation by using laser sensors (2-3) arranged in an alternating manner, and drives the six-degree-of-freedom intelligent following air-floating platform to follow the movement of the mission load (1-12) through the Mecanum drive module (1-10).

5. The six-degree-of-freedom intelligent following air-bearing platform according to claim 1, characterized in that: The combined bracket (1-9) includes an air float plate limiting block (3-1), four support rollers (3-2), an arc-shaped guide rail (3-3), four laser sensor light shields (3-4), an air foot (3-5), and a force sensor (3-6); The air flotation plate limiting block (3-1) is arranged below the combined bracket (1-9) to prevent the combined bracket (1-9) from tipping over; Four support rollers (3-2) are symmetrically installed on the combined bracket (1-9); Four laser sensor light shields (3-4) are installed perpendicularly to each other around the combined bracket (1-9); The support roller (3-2) is used to support the task load (1-12), so that the task load (1-12) rotates on the support roller (3-2) about its own axis; The arc-shaped guide rail (3-3) is connected to the support roller (3-2), enabling the task load (1-12) to pitch in the vertical plane; The arc-shaped guide rail (3-3) is fixedly connected to the combined bracket (1-9), and the lower part of the arc-shaped guide rail (3-3) is fixedly connected to the force sensor (3-6), which is used to measure the unloading force value; An air foot (3-5) is installed below the combined bracket (1-9), which enables three-degree-of-freedom motion on the air-floating plate (1-5); The vertical displacement of the air-floating plate (1-5) is achieved by using the air-floating guide rail (1-6) and the air-floating slider (1-4); The support roller (3-2), the arc-shaped guide rail (3-3), the air foot (3-5), and the air-bearing guide rail (1-6) together realize the six-degree-of-freedom motion of the task load (1-12); Four Mecanum drive modules (1-10) are symmetrically installed below the air-bearing support platform (1-11); The gravity unloading subsystem is installed above the air flotation support platform (1-11).

6. The six-degree-of-freedom intelligent following air-bearing platform according to claim 1, characterized in that: The measurement and control subsystem includes a host computer (human-machine interaction module) and a slave computer (1-15) (control module); the slave computer (1-15) includes a fully packaged encoder, AD acquisition board, motor drive board, and STM32 control board.

7. The six-degree-of-freedom intelligent following air-bearing platform according to claim 1, characterized in that: The measurement and control subsystem obtains the distance between the three laser sensors (2-3) and the laser sensor shielding plate (3-4), and then calculates and converts the translation and rotation of the object in the plane into the driving signal of the Mecanum drive module, thereby driving the six-degree-of-freedom intelligent following air-bearing platform to move.

8. A six-degree-of-freedom intelligent following air-bearing platform according to claim 1, characterized in that: A level (2-1) and an inertial measurement element (2-2) are mounted on an air-floating plate (1-5) to measure the tilt angle of the air-floating plate (1-5); The lidar (1-13) is installed above the column (1-7). The lidar (1-13) measures the position of the six-degree-of-freedom intelligent following air-floating platform in the field, and the laser displacement sensors (1-14) arranged at the four corners of the air-floating support platform (1-11) measure the tilt angle of the air-floating support platform (1-11). The lifting motor (4-1) is fixed to the Z-beam (4-5); The lifting screw (4-2) is fixed to the drive end of the lifting motor (4-1); The lifting motor (4-1) can control the suspension support plate (4-3) to move up and down along the suspension support optical axis (4-4) by driving the lifting screw (4-2). During the six-degree-of-freedom intelligent following of the air-floating platform, it can servo the ground height error in real time, so that the air-floating support platform (1-11) can be kept in a horizontal state.

9. A six-degree-of-freedom intelligent following air-bearing platform according to claim 1, characterized in that: The counterweights in the counterweight box (1-8) are selected using multiple thin steel plates. By increasing or decreasing the number of thin steel plates, the mass of one end of the combined bracket (1-9) is balanced, thereby improving the ability of the six-degree-of-freedom intelligent following air-floating platform to adapt to different spatial deployment mechanisms. The air-bearing guide rail (1-6), air-bearing slider (1-4), air foot (3-5), and support roller (3-2) are equipped with dustproof devices.

10. The method for intelligent following using a six-degree-of-freedom intelligent following air-bearing platform as described in claim 1, characterized in that the steps are... include: In servo control mode, the combined bracket (1-9) and air-bearing guide rail (1-6) are opened to supply air, and the six-degree-of-freedom intelligent following air-bearing platform actively follows the movement of the large-scale spatial multi-joint mechanism; When the large space multi-joint mechanism moves vertically, the number of counterweights in the counterweight box (1-8) is adjusted to balance the friction of the air-bearing guide rail (1-6), and the position of the air-bearing plate (1-5) is adjusted to achieve zero-gravity test of the large space deployment mechanism; The horizontal adjustment is achieved by measuring the position of the six-degree-of-freedom intelligent following air-float platform using a lidar (1-13), measuring the ground height using a laser sensor (2-3), and measuring the tilt angle of the air-float platform (1-5) using an inertial measurement unit and a level installed on the air-float platform (1-5). The tilt angle of the air-float platform (1-5) is adjusted by the four corner lifting motors (4-1) of the air-float support platform (1-11), so that the six-degree-of-freedom intelligent following air-float platform can adapt to the self-leveling ground in real time and ensure that the air-float platform (1-5) is level.

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