A suspension type six-degree-of-freedom spacecraft dynamics simulation device
By using a suspended six-degree-of-freedom spacecraft dynamics simulation device, which employs a suspended air-bearing ball bearing and a constant force unloading mechanism, the problems of insufficient accuracy and high complexity of existing six-degree-of-freedom air-bearing platforms in simulating small spacecraft have been solved, achieving high-precision dynamics simulation and cost reduction.
Patent Information
- Application Number
- CN202411257392.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-09
- Publication Date
- 2025-12-12
- Estimated Expiration
- 2044-09-09
AI Technical Summary
Existing six-degree-of-freedom air-bearing platforms suffer from insufficient accuracy and high mechanical complexity when simulating the six-degree-of-freedom kinematics and dynamics of small spacecraft, making it difficult to meet high-precision requirements, especially in space precision control and on-orbit assembly and maintenance missions.
A suspended six-degree-of-freedom spacecraft dynamics simulation device was designed, including three-degree-of-freedom translation and three-degree-of-freedom rotation. It adopts a suspended air-bearing ball bearing and a constant force unloading mechanism, and achieves high-precision dynamics simulation through a suspension wire tilt angle detection system, thereby reducing the complexity of the mechanism and control.
It achieves high-precision six-degree-of-freedom dynamic simulation of spacecraft targets, reduces manufacturing costs, improves simulation accuracy, and is suitable for on-orbit maintenance and ground testing.
Smart Images
Figure CN119329790B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to a kind of suspension six degrees of freedom spacecraft dynamics simulation device, belong to on-orbit maintenance technical field. BACKGROUND
[0002] Low gravity simulation is the basis of ground test for space exploration, and six degrees of freedom dynamics simulation device is an important technical means for ground verification of spacecraft orbit and attitude control. The existing satellite six degrees of freedom dynamics simulation device is a six degrees of freedom air floating table, which includes a three-axis rotating platform, a translation base and a gravity unloading z-axis. This device is used in the ground verification of many tasks and has made great contribution to space exploration.
[0003] However, the six degrees of freedom air floating table itself also has certain limitations. The simulation accuracy and stroke of the z-axis are limited by the mechanism and control, and the additional mass of the base and z-axis leads to different masses of the translation and rotation parts. Especially with the development of space fine control, on-orbit assembly and maintenance, there is a demand for high-precision dynamics simulation of small spacecraft. SUMMARY
[0004] The technical problem solved by the present application is to provide a suspension six degrees of freedom spacecraft dynamics simulation device to solve the problem of the accuracy of six degrees of freedom kinematics and dynamics simulation of small spacecraft, and to reduce the production cost and the complexity of mechanism and control.
[0005] The technical solution of the present application is a suspension six degrees of freedom spacecraft dynamics simulation device, the six degrees of freedom including three degrees of freedom translation and three degrees of freedom rotation, the three degrees of freedom translation being movement in the horizontal plane in two coordinate axis directions and vertical direction, and the three degrees of freedom rotation being rotation around the horizontal plane in two coordinate axis directions and vertical direction, the device comprising a support, a translation guide rail, a telescopic suspension arm, a suspension wire, a fixed pulley, a constant force unloading mechanism, a suspension wire inclination detection system and a three degrees of freedom rotation target.
[0006] The translation guide rail is installed on the support and located in the horizontal plane, and can move in one coordinate axis direction of the horizontal plane.
[0007] The telescopic suspension arm is fixedly installed at one end on the translation guide rail and moves with the translation guide rail, and a fixed pulley is installed at the other end, and the telescopic suspension arm can extend and retract in another coordinate axis direction of the horizontal plane. The two-dimensional movement of the telescopic suspension arm in the horizontal plane realizes the following of the two-dimensional movement of the unloading target in the horizontal plane.
[0008] The suspension wire is used to suspend the air floating ball bearing of the three degrees of freedom rotation target at one end, and extends along the direction of the telescopic suspension arm by passing through the fixed pulley installed at the end of the telescopic suspension arm at the other end, and is connected to the constant force unloading mechanism.
[0009] The three-degree-of-freedom rotating target is provided with a gas ball bearing mechanism, and the three-degree-of-freedom rotating target shell can rotate freely in three degrees of freedom around the center of the gas ball bearing ball; and the gas supply pipe supplies gas to the gas ball bearing mechanism;
[0010] The constant force unloading mechanism is installed on the telescopic cantilever, adopts a constant force control principle, controls the wire to move freely along the vertical direction following the three-degree-of-freedom rotating target, and always maintains a constant unloading tension, so as to realize weightlessness simulation in the vertical direction;
[0011] The wire inclination detection system is used for detecting the included angle between the wire and the plane formed by the horizontal direction and the vertical direction, and the included angle between the wire and the plane formed by the vertical direction and the vertical direction.
[0012] The control computer obtains a motion control instruction through feedback closed-loop calculation according to the measurement result of the wire inclination detection system, drives the horizontal guide rail and the telescopic cantilever to move, so that the wire keeps unchanged in the vertical direction during the movement of the three-degree-of-freedom rotating target, and then the horizontal position tracking of the three-degree-of-freedom rotating target is realized.
[0013] Preferably, the constant force unloading mechanism comprises a roller, a motor and a dynamometer.
[0014] The motor is used for controlling the rotation of the roller, the wire is fixed and wound on the roller, and the dynamometer is used for measuring the tension of the wire and is used for constant force closed-loop feedback control of the constant force unloading mechanism.
[0015] Preferably, the three-degree-of-freedom rotating target comprises a gas pipe interface, a wire interface, a ducted thruster, a first balance adjusting mechanism, an industrial computer, a gas ball bearing, a second balance adjusting mechanism, an inertial measurement unit and a gas supply pipe.
[0016] The gas ball bearing is lubricated by gas floating, so that the three-degree-of-freedom rotating target can rotate in three degrees of freedom.
[0017] The gas pipe interface is used for connecting the gas supply pipe to supply gas to the gas ball bearing.
[0018] The wire interface is used for connecting the wire.
[0019] The ducted thruster is an actuator in the three-degree-of-freedom rotating target, which is used to provide thrust to the target to control the translational position movement and the rotating attitude of the target.
[0020] The first balance adjusting mechanism and the second balance adjusting mechanism are used for adjusting the projection position of the mass center of the three-degree-of-freedom rotating target in the horizontal plane; when the mass center coincides with the center of the gas ball bearing, the suspended three-degree-of-freedom rotating target completely eliminates the influence of gravity and can simulate the free rotation state in orbit.
[0021] Industrial computer, used for controlling the switching state of each ducted thruster.
[0022] Preferably, the ducted thruster is a one-way thruster.
[0023] Preferably, the number of the ducted thrusters is two, and two pairs of ducted thrusters are used to control each degree of freedom.
[0024] Preferably, the air-floating ball bearing comprises a hanging rope joint, a convex ball gas pipe joint, a rotating concave ball and a suspension convex ball.
[0025] The suspension convex ball is fixedly connected with the convex ball suspension wire joint, and the convex ball suspension wire joint is a suspension connection end of the three-degree-of-freedom rotating target; the convex ball gas pipe joint is used for connecting the suspension convex ball and supplying gas for the suspension convex ball; the suspension convex ball is provided with a gas outlet hole; and an air-floating lubricating layer is formed on the contact surface between the suspension convex ball and the rotating concave ball, so that the suspension convex ball and the rotating concave ball can be freely rotated without friction.
[0026] The rotating concave ball is connected with the structural member of the three-degree-of-freedom rotating target through a concave ball flange.
[0027] Preferably, the three-degree-of-freedom rotating target can rotate 360 degrees around the vertical direction, and can rotate around the rail direction and the vertical rail direction in the horizontal plane in the air-floating state.
[0028] Preferably, the air-floating ball bearing comprises a convex ball flange, a rotating convex ball, a suspension concave ball, a concave ball suspension wire joint and a concave ball gas path interface.
[0029] The concave ball suspension wire joint and the concave ball gas path interface are fixed on the suspension concave ball, the convex ball flange is fixedly installed with the rotating convex ball, the rotating convex ball is connected and fixed with the structural member of the three-degree-of-freedom rotating target through the convex ball flange; the rotating convex ball is located inside the suspension concave ball, gas is sprayed from the suspension concave ball, and an air-floating lubricating layer is formed between the suspension concave ball and the rotating convex ball; so that the suspension concave ball and the convex ball flange can be freely rotated without friction.
[0030] Preferably, the first balance adjusting mechanism and the second balance adjusting mechanism adjust the mass center position of the three-degree-of-freedom rotating target by moving the slider mass.
[0031] Compared with the prior art, the present application has the following beneficial effects:
[0032] (1) The suspension type six-degree-of-freedom spacecraft dynamics simulation device designed by the present application realizes high-precision six-degree-of-freedom dynamics simulation of the spacecraft target, has the characteristics of high dynamics simulation precision and does not need a granite platform, and is convenient for carrying out on-orbit maintenance and repair ground test experiments in a laboratory.
[0033] (2), the suspension type air floating ball bearing structure designed by the application realizes high-precision simulation of three degrees of freedom rotation of a small satellite target through a suspension mode, ensures the precision of attitude dynamics simulation, and facilitates verification of attitude control algorithms.
[0034] (3), the translation following mechanism designed by the application contains three degrees of freedom, wherein the vertical direction adopts a constant force control mode to realize high-precision gravity unloading; the two horizontal degrees of freedom are realized by a translation following control principle, that is, the inclination of a wire is detected, a translation mechanism is closed-loop controlled to make the wire always keep in the vertical direction, and the following of the horizontal position is realized. BRIEF DESCRIPTION OF DRAWINGS
[0035] Figure 1 is a whole structure schematic diagram of an embodiment of the application.
[0036] Figure 2 is a three degrees of freedom rotation target schematic diagram of an embodiment of the application.
[0037] Fig. 3 is a suspension convex ball bearing structure schematic diagram of an embodiment of the application.
[0038] Figure 4 is a suspension concave ball bearing structure schematic diagram of an embodiment of the application.
[0039] Fig. 5(a) is an xoy plane schematic diagram of an embodiment of the application.
[0040] Fig. 5(b) is a zoy plane or zox plane schematic diagram of an embodiment of the application.
[0041] Fig. 5(c) is a thruster position schematic of an embodiment of the application. DETAILED DESCRIPTION
[0042] The application will be further described in detail below in combination with the drawings and embodiments.
[0043] The suspension type low gravity simulation device based on constant tension has been used in gravity unloading of a mechanical arm, etc., and is a simple, reliable and effective low gravity simulation device. The suspension type air floating ball bearing device is proposed in the six degrees of freedom spacecraft dynamics simulator of the application, three degrees of freedom translation dynamics simulation is realized by using a constant tension unloading mode, and three degrees of freedom rotation dynamics simulation is realized by using a suspension type air floating ball bearing.
[0044] Figure 1An overall structure schematic diagram of a specific embodiment of a suspension type six-degree-of-freedom spacecraft dynamics simulator is provided. The six degrees of freedom include three degrees of freedom of translation and three degrees of freedom of rotation, the three degrees of freedom of translation are movements in the directions of two coordinate axes of a horizontal plane and a vertical direction, and the three degrees of freedom of rotation are rotations around the directions of two coordinate axes of the horizontal plane and the vertical direction. From the simulation principle of the six-degree-of-freedom spacecraft dynamics characteristics, the embodiment is different from the general air floating table simulation mode. The three-dimensional translation is realized by a suspension active translation following system, and the three degrees of freedom of rotation are realized by a suspension type ball bearing.
[0045] As Figure 2 , the device of the embodiment is composed of a suspension type three-dimensional translation tracking system and an air floating three-degree-of-freedom rotation target, and specifically includes a support 1, a translation guide rail 2, an extension suspension arm 3, a constant force unloading wire 4, a wire, a fixed pulley, a wire inclination detection system 5, and a three-degree-of-freedom rotation target 7.
[0046] The support 1 is vertically installed on the ground and is used for installing a three-degree-of-freedom translation tracking suspension unit. The three-degree-of-freedom translation tracking suspension unit includes the translation guide rail 2, the extension suspension arm 3, the constant force unloading mechanism 4, the wire, the fixed pulley, and the wire inclination detection system 5.
[0047] The translation guide rail 2 is installed on the support 1 and can translate along the direction of one coordinate axis of a horizontal plane.
[0048] The extension suspension arm 3 is fixedly installed at one end on the translation guide rail 2 and has a fixed pulley installed at the other end, and can extend and retract along the direction of another degree of freedom of the horizontal plane.
[0049] The wire is used for suspending the three-degree-of-freedom rotation target 7 at one end, passes through the fixed pulley installed at the one end of the extension suspension arm 3, extends along the extension suspension arm 3, and is connected to the constant force unloading mechanism 4.
[0050] The three-degree-of-freedom rotation target 7 is internally provided with an air floating ball bearing mechanism and can freely rotate in three degrees of freedom around the ball center of the air floating ball bearing.
[0051] The low-pressure air pipe 6 is suspended on the support and supplies air to the three-degree-of-freedom rotation target suspended on the wire, and moves up and down with the three-degree-of-freedom rotation target.
[0052] Constant force unloading mechanism 4 is installed on telescopic boom 3, adopts constant force control principle, controls the wire to follow the three-degree-of-freedom rotating target to move freely in vertical direction, and always keeps constant unloading tension, realizes weightlessness simulation in vertical direction;
[0053] Wire inclination detection system 5 is used for detecting the inclination of the wire in two-degree-of-freedom direction caused by the horizontal movement of the three-degree-of-freedom rotating target 7;
[0054] Control computer obtains motion control instruction according to the inclination feedback of the wire in two-degree-of-freedom direction obtained by wire inclination detection system 5, drives the movement of translation guide rail 2 and telescopic boom 3, so that the wire keeps unchanged in vertical direction during the movement of three-degree-of-freedom rotating target 7, and then realizes horizontal position tracking of three-degree-of-freedom rotating target 7.
[0055] It can be seen that among the three translational degrees of freedom of the spacecraft dynamics simulation device, the horizontal two degrees of freedom are simulated and realized through support 1, translation guide rail 2, telescopic boom 3 and wire inclination detection system 5; and the vertical degree of freedom is realized by constant force unloading mechanism 4.
[0056] The constant force unloading mechanism 4 comprises a roller, a motor and a dynamometer.
[0057] The motor is used for controlling the rotation of the roller; the wire is fixed and wound on the roller; and the dynamometer is used for measuring the tension of the wire.
[0058] Three-degree-of-freedom rotating target 7 is a rotating platform in simulating spacecraft dynamics, used for simulating three-degree-of-freedom rotation of the target, carrying inertial measurement unit IMU and thruster, etc., to realize three-degree-of-freedom attitude control.
[0059] The three-degree-of-freedom rotating target 7 comprises air pipe interface 8, wire interface 9, ducted thruster 10, first balance adjusting mechanism 11, industrial computer 12, air floating ball bearing 13, second balance adjusting mechanism 14 and inertial measurement unit 26.
[0060] Air floating ball bearing 13 enables the three-degree-of-freedom rotating target to rotate in three degrees of freedom through air floating lubrication.
[0061] Air pipe interface 8 is used for supplying air to air floating ball bearing 13 and is connected with air supply pipe 6.
[0062] Wire interface 9 is a connection suspension interface for supplying air to ball bearing inside the three-degree-of-freedom rotating target, used for connecting the wire.
[0063] Ducted thruster 10 is an executing mechanism in the three-degree-of-freedom rotating target, used for providing thrust to the target to control the translational position movement and rotating attitude of the target.
[0064] The first balance adjusting mechanism 11 and the second balance adjusting mechanism 14 are used for adjusting the position of the mass center of the three-degree-of-freedom rotating target 7 in the horizontal plane; when the mass center coincides with the ball center of the air-floating ball bearing 13, the suspended three-degree-of-freedom rotating target completely eliminates the influence of gravity and can simulate the in-orbit free rotation state.
[0065] The industrial computer 12 is used for controlling the on-off state of each ducted thruster 10, thereby controlling the attitude of the three-degree-of-freedom rotating target.
[0066] The ducted thruster 10 is a one-way thruster.
[0067] The principle of the thruster design is to be used in pairs, and the position control and the attitude control are decoupled. Since the thruster is one-way, two directions are formed for each degree of freedom. Therefore, the number of the ducted thrusters 10 is 24, and two pairs of the ducted thrusters 10 are used for controlling each degree of freedom. The specific layout is as follows:
[0068] The position of the three-degree-of-freedom rotating target is represented by a coordinate system oxyz, o represents the origin, which is also the ball center of the ball bearing, and x, y and z are three coordinate axes parallel to the edges of the three-degree-of-freedom rotating target, and the x and y axes are along the directions of the first balance adjusting mechanism and the second balance adjusting mechanism, respectively. The 12 thrusters for position control are arranged on the xoy (horizontal) plane, and the other 4 thrusters are arranged on the yoz or zox plane, as shown in Figures 5(a) to 5(b) The directions of the thrusters are shown in the figure.
[0069] The ducted thrusters for attitude control are used in pairs to form a couple, and the direction of the couple needs to be parallel to the xoy, yoz and zox planes, and can be installed on the top surface, as shown in FIG. 5(c). Twelve thrusters can be arranged at the four vertices of the top surface, and three thrusters are arranged at each corner, and “×” represents the vertical plane downward, and “·” represents the vertical plane upward.
[0070] The air-floating ball bearing 13 has two implementation modes.
[0071] The first implementation mode is shown in FIG. 3. The air-floating ball bearing 13 includes a hanging rope joint 15, a convex ball air pipe joint 16, a rotating concave ball 17 and a suspension convex ball 18.
[0072] The suspension convex ball 18 is fixedly connected with the convex ball hanging wire joint 15, and the convex ball hanging wire joint 15 is a suspension connection end of the three-degree-of-freedom rotating target; the convex ball air pipe joint 16 is used for connecting the suspension convex ball 18 and supplying air to the suspension convex ball 18, the suspension convex ball 18 is provided with an air outlet hole for air outlet, and a gas-floating lubricating layer is formed on the contact surface between the suspension convex ball 18 and the rotating concave ball 17, so that the suspension convex ball 18 and the rotating concave ball 17 can realize free rotation without friction;
[0073] The rotating concave ball 17 is connected with the structural member of the three-degree-of-freedom rotating target through the concave ball flange 19.
[0074] In one embodiment of the present application, the convex ball air pipe joint 16 and the convex ball suspension wire joint 15 are respectively the air supply end and the suspension connection end of the three-degree-of-freedom rotating target. The low-pressure air with a pressure not higher than 0.8 MPa is discharged through the air outlet hole on the suspension convex ball 18, and a gas-float lubricating layer with a thickness of about 10 microns is formed on the contact surface between the suspension convex ball 18 and the rotating concave ball 17, so that the suspension convex ball 18 and the rotating concave ball 17 can realize nearly friction-free free rotation. The rotating concave ball 17 is connected with the structural member of the three-degree-of-freedom rotating target through the concave ball flange 19, and three friction-free rotational degrees of freedom of the three-degree-of-freedom rotating target relative to the ball bearing, i.e., rolling, pitching and yawing, are realized. The three-degree-of-freedom rotating target 7 can rotate 360° around the vertical axis in the gas-float state, and can rotate not less than ±12° around the two horizontal axes.
[0075] The second implementation manner is as shown in Figure 4 . Figure 4 The difference from Figure 2 is that the suspension type ball bearing structure is different. The gas-float ball bearing 13 includes a convex ball flange 20, a rotating convex ball 21, a suspension concave ball 22, a target box 23, a concave ball suspension wire joint 25 and a concave ball air path interface 24.
[0076] The concave ball suspension wire joint 25 and the concave ball air path interface 24 are fixed on the suspension concave ball 22, the convex ball flange 20 is fixedly installed with the rotating convex ball 21, the rotating convex ball 21 is connected and fixed with the structural member of the three-degree-of-freedom rotating target through the convex ball flange 20; the rotating convex ball 21 is located inside the suspension concave ball 22, the gas is sprayed from the suspension concave ball 22, and a gas-float lubricating layer is formed between the suspension concave ball 22 and the rotating convex ball 21; so that the suspension concave ball 22 and the convex ball flange 20 can realize friction-free free rotation.
[0077] The first balance adjusting mechanism 11 and the second balance adjusting mechanism 14 are used for adjusting the mass center position of the six-degree-of-freedom target by moving the slider mass, and finally making the six-degree-of-freedom target balanced in the horizontal plane x, y direction.
[0078] The closed-loop control system of the three-degree-of-freedom translational unit includes two-axis translational control and constant force tracking control of the vertical axis. The translation guide rail 2 and the telescopic suspension arm 3 are used to control the two-dimensional position of the suspension wire in the guide rail direction and the vertical guide rail direction through translation and telescopic extension. The suspension wire inclination detection system 5 can detect the inclination of the suspension wire in the guide rail direction and the vertical guide rail direction at the same time, that is, the deviation between the suspension point and the target position. At this time, the control computer calculates the control instruction according to the suspension wire inclination feedback closed loop and sends it to the translation guide rail 2 and the telescopic suspension arm 3, so as to finally realize high-precision horizontal position tracking of the suspension wire. The constant force control method is used in the vertical direction. The constant force unloading suspension wire is connected with the three-degree-of-freedom rotating target 7, can move up and down with the three-degree-of-freedom rotating target, and always maintains a constant unloading tension, which is used to realize weightlessness simulation in the vertical direction.
[0079] The closed-loop control system of the three-degree-of-freedom rotating unit is used to complete platform centroid adjustment and reduce interference torque according to the gyro signal before control. When control is performed, the control program calculates the control amount according to the measured results of the gyro attitude signal, converts it into the thrust of the ducted fan, sends the instruction to the ducted thruster 10, and performs attitude stabilization control or maneuvering control.
[0080] The constant force unloading suspension wire is a connecting suspension wire of the suspended three-degree-of-freedom rotating target, and is connected to the constant force unloading mechanism at the upper end. The suspension wire can move freely in the vertical direction with the movement of the three-degree-of-freedom rotating target by using the constant force control principle. The suspension wire inclination detection system 5 is used to detect the inclination of the suspension wire caused by the horizontal movement of the three-degree-of-freedom rotating target.
[0081] Although the present application has been disclosed with the above preferred embodiments, it is not intended to limit the present application, and any person skilled in the art can make possible changes and modifications to the technical solutions of the present application by using the disclosed methods and technical contents without departing from the spirit and scope of the present application. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present application, which does not deviate from the technical solutions of the present application, belongs to the protection scope of the technical solutions of the present application.
Claims
1. A suspended six-degree-of-freedom spacecraft dynamics simulator, the six degrees of freedom including three degrees of translation and three degrees of rotation, the three degrees of translation being movement in two horizontal coordinate axis directions and a vertical direction, the three degrees of rotation being rotation about the two horizontal coordinate axis directions and the vertical direction, characterized by, The device comprises a support (1), a translation guide rail (2), a telescopic cantilever (3), a suspension wire, a fixed pulley, a constant force unloading mechanism (4), a suspension wire inclination detection system (5), and a three-degree-of-freedom rotating target (7). The translation guide rail (2) is installed on the support (1) and located on a horizontal plane, and can move along a coordinate axis direction of the horizontal plane. The telescopic cantilever (3) is fixedly installed at one end on the translation guide rail (2) and moves along with the translation guide rail (2), and a fixed pulley is installed at the other end, and the telescopic cantilever can be telescoped along another coordinate axis direction of the horizontal plane; the two-dimensional movement of the telescopic cantilever on the horizontal plane realizes the following of the unloading target in the two-dimensional movement on the horizontal plane. The suspension wire is used for suspending the air floating ball bearing of the three-degree-of-freedom rotating target (7) at one end, and extends along the direction of the telescopic cantilever (3) by passing through the fixed pulley installed at the one end of the telescopic cantilever (3) and is connected to the constant force unloading mechanism (4). The three-degree-of-freedom rotating target (7) is internally provided with an air floating ball bearing mechanism, the three-degree-of-freedom rotating target shell can be freely rotated in three degrees of freedom around the air floating ball bearing ball center; the air supply pipe (6) supplies air to the air floating ball bearing mechanism. The constant force unloading mechanism (4) is installed on the telescopic cantilever (3) and adopts a constant force control principle to control the suspension wire to freely move along the vertical direction with the three-degree-of-freedom rotating target and always maintain a constant unloading tension, thereby realizing the weightlessness simulation in the vertical direction. The suspension wire inclination detection system (5) is used for detecting the included angle between the suspension wire and the plane formed by the direction of the translation guide rail (2) and the vertical direction, and the included angle between the suspension wire and the plane formed by the direction of the vertical guide rail and the vertical direction. The control computer obtains the motion control instruction through feedback closed loop calculation according to the measurement result of the suspension wire inclination detection system (5), drives the translation guide rail (2) and the telescopic cantilever (3) to move, and makes the suspension wire keep the vertical direction unchanged during the movement of the three-degree-of-freedom rotating target (7), thereby realizing the horizontal position tracking of the three-degree-of-freedom rotating target (7). The three-degree-of-freedom rotating target (7) comprises an air pipe interface (8), a suspension wire interface (9), a ducted thruster (10), a first balance adjusting mechanism (11), an industrial computer (12), an air floating ball bearing (13), a second balance adjusting mechanism (14), an inertial measurement unit (26), and an air supply pipe (6). The air floating ball bearing (13) enables the three-degree-of-freedom rotating target to rotate in three degrees of freedom through air floating lubrication. The air pipe interface (8) is used for the air pipe interface for supplying air to the air floating ball bearing (13) and is connected to the air supply pipe (6). The suspension wire interface (9) is used for connecting the suspension wire. The ducted thruster (10) is an execution mechanism in the three-degree-of-freedom rotating target and is used for providing thrust to the target to control the translational position movement and the rotating attitude. The first balance adjusting mechanism (11) and the second balance adjusting mechanism (14) are used for adjusting the projection position of the center of mass of the three-degree-of-freedom rotating target (7) on the horizontal plane; when the center of mass coincides with the ball center of the air floating ball bearing (13), the three-degree-of-freedom rotating target after being suspended completely eliminates the influence of gravity and can simulate the on-orbit free rotation state. The industrial computer (12) is used for controlling the switching state of each ducted thruster (10).
2. A suspended six degree of freedom spacecraft dynamics simulator according to claim 1, wherein, The constant force unloading mechanism (4) comprises a roller, a motor, and a dynamometer. The motor is used for controlling the rotation of the roller; the wire is fixed and wound on the roller; the dynamometer is used for measuring the tension of the wire and for the constant force closed-loop feedback control of the constant force unloading mechanism.
3. The suspended six-degree-of-freedom spacecraft dynamics simulator of claim 1, wherein, The ducted thruster (10) is a one-way thruster.
4. A suspended six degree of freedom spacecraft dynamics simulator according to claim 3, wherein, The number of the ducted thrusters (10) is 24, and two pairs of ducted thrusters (10) are used for controlling each degree of freedom.
5. The suspended six-degree-of-freedom spacecraft dynamics simulator of claim 1, wherein, The air floating ball bearing (13) comprises a convex ball wire joint (15), a convex ball air pipe joint (16), a rotating concave ball (17), and a suspended convex ball (18). The suspended convex ball (18) is fixedly connected with the convex ball wire joint (15), the convex ball wire joint (15) is a suspended connection end of the three-degree-of-freedom rotating target; the convex ball air pipe joint (16) is used for connecting the suspended convex ball (18) and supplying air to the suspended convex ball (18); the suspended convex ball (18) is provided with an air outlet; and an air floating lubricating layer is formed on the contact surface between the suspended convex ball (18) and the rotating concave ball (17), so that the suspended convex ball (18) and the rotating concave ball (17) can realize free rotation without friction. The rotating concave ball (17) is connected with the structural member of the three-degree-of-freedom rotating target through a concave ball flange (19).
6. The suspended six-degree-of-freedom spacecraft dynamics simulator of claim 1, wherein, The three-degree-of-freedom rotating target (7) can rotate 360° around the vertical direction, and can rotate around the rail direction and the vertical rail direction in the horizontal plane in the air floating state.
7. The suspended six-degree-of-freedom spacecraft dynamics simulator of claim 1, wherein, The air floating ball bearing (13) comprises a convex ball flange (20), a rotating convex ball (21), a suspended concave ball (22), a concave ball wire joint (25), and a concave ball air path interface (24). The concave ball wire joint (25) and the concave ball air path interface (24) are fixed on the suspended concave ball (22), the convex ball flange (20) is fixedly installed with the rotating convex ball (21), the rotating convex ball (21) is connected and fixed with the structural member of the three-degree-of-freedom rotating target through the convex ball flange (20); the rotating convex ball (21) is located inside the suspended concave ball (22), air is sprayed from the suspended concave ball (22), and an air floating lubricating layer is formed between the suspended concave ball (22) and the rotating convex ball (21); so that the suspended concave ball (22) and the convex ball flange (20) can realize free rotation without friction.
8. The suspended six-degree-of-freedom spacecraft dynamics simulator of claim 1, wherein, The first balance adjusting mechanism (11) and the second balance adjusting mechanism (14) adjust the mass center position of the three-degree-of-freedom rotating target by moving the slider mass.
Citation Information
Patent Citations
Gravity unloading device for multi-joint spatial mechanism
CN107757955A
Multi-star suspension type microgravity simulation system
CN109515769A