A control method and system for a parallel vibration damping mechanism

Abstract

The present invention discloses a control method and system for a parallel vibration damping mechanism. The parallel vibration damping mechanism includes a moving platform and a fixed platform. The centers of the moving platform and the fixed platform are connected by a passive connection mechanism. The moving platform is fixedly connected to the passive connection mechanism, and the fixed platform is movably connected to the passive connection mechanism. The four corners of the moving platform and the fixed platform are all movably connected by an active connection mechanism, and the active connection mechanism is driven by a driving mechanism. The method includes: obtaining the pose information of the moving platform and the fixed platform; calculating the screw equations of the center point of the moving platform, the first movable connection point, and the second movable connection point; according to the screw equations, performing dynamic modeling on the parallel vibration damping mechanism to obtain a dynamic model; according to the pose information of the moving platform and the fixed platform and the dynamic model, calculating the control force of the driving mechanism; controlling the active connection mechanism according to the control force to adjust the pose information of the moving platform. The present invention controls the moving platform according to the output of the driving mechanism to maintain the balance of the moving platform in different postures.

Description

Technical Field

[0001] The present invention relates to the technical field of vibration damping control, and particularly to a control method and system for a parallel vibration damping mechanism. Background Art

[0002] When moving vehicles such as vehicles and ships encounter road bumps or sea waves during driving, most active vibration damping mechanisms adopt a vibration damping method of acceleration compensation. However, this method ignores the influence generated when the attitude of the vibration damping mechanism changes, resulting in an unsatisfactory vibration damping effect.

[0003] In addition, the configuration of a general vibration damping mechanism cannot ensure that while reducing the sway in the pitch and roll directions, the center of the tabletop does not move on the plane, and its vibration damping efficiency is always limited. For high-frequency vibration situations, the reaction speed of the driving device of the active vibration damping mechanism is difficult to follow the road excitation in a bumpy environment, and its pose balance has hysteresis, making it difficult to achieve an ideal vibration damping effect.

[0004] In the dynamic control of an active vibration damping mechanism, the dynamic model of a parallel robot is often required. However, an inaccurate dynamic model often leads to poor control effects, and an accurate dynamic model has a complex form and is not suitable for an embedded system that requires real-time performance.

[0005] Therefore, how to improve the vibration damping effect and stability of an active vibration damping mechanism is of great significance. Summary of the Invention

[0006] In order to solve the above technical problems, the present invention provides a control method and system for a parallel vibration damping mechanism.

[0007] Specifically, the technical solution of the present invention is as follows:

[0008] The present invention provides a control method for a parallel vibration damping mechanism, which is applied to a parallel vibration damping mechanism. The parallel vibration damping mechanism includes a moving platform and a fixed platform. The centers of the moving platform and the fixed platform are connected by a passive connection mechanism. The moving platform is fixedly connected to the passive connection mechanism, and the fixed platform is movably connected to the passive connection mechanism. Moreover, the four corners of the moving platform and the fixed platform are movably connected by an active connection mechanism, and the active connection mechanism is driven by a driving mechanism, including:

[0009] Obtain the pose information of the moving platform and the fixed platform respectively. The pose information includes pitch angular velocity, roll angular velocity, and vertical velocity;

[0010] Calculate the screw equations of the center point of the moving platform, the first active connection point, and the second active connection point respectively. The screw equations include the velocity screw equation and the force screw equation. The first active connection point is the connection point between the active connection mechanism and the moving platform, and the second active connection point is the connection point between the active connection mechanism and the fixed platform and the connection point between the passive connection mechanism and the fixed platform;

[0011] According to the screw equations, perform dynamic modeling on the parallel vibration reduction mechanism to obtain the dynamic model of the parallel vibration reduction mechanism;

[0012] According to the pose information of the moving platform and the fixed platform and the dynamic model, calculate the control force of the driving mechanism;

[0013] Control the active connection mechanism according to the control force to adjust the pose information of the moving platform.

[0014] In some embodiments, the calculating the control force of the driving mechanism according to the pose information and the dynamic model includes:

[0015] According to the pitch angular velocity and roll angular velocity of the moving platform and the fixed platform, calculate the pitch angle difference, roll angle difference, pitch angular velocity difference, roll angular velocity difference, pitch angular acceleration difference, and roll angular acceleration difference between the fixed platform and the moving platform;

[0016] According to the vertical velocities of the moving platform and the fixed platform, calculate the vertical error value between the fixed platform and the moving platform. The vertical error value includes the vertical displacement difference, vertical velocity difference, and vertical acceleration difference;

[0017] Substitute the pitch angle difference, roll angle difference, pitch angular velocity difference, roll angular velocity difference, pitch angular acceleration difference, roll angular acceleration difference, and vertical error value into the dynamic model to calculate the control force of the driving mechanism.

[0018] In some embodiments, the calculating the pitch angle difference, roll angle difference, pitch angular velocity difference, roll angular velocity difference, pitch angular acceleration difference, and roll angular acceleration difference between the fixed platform and the moving platform according to the pitch angular velocity and roll angular velocity of the moving platform and the fixed platform includes:

[0019] According to the pitch angular velocity and roll angular velocity of the moving platform and the fixed platform, calculate the pitch angle and roll angle of the moving platform and the fixed platform, and the pitch angular acceleration and roll angular acceleration of the fixed platform;

[0020] Calculate the pitch angle difference, roll angle difference, pitch angular velocity difference, and roll angular velocity difference between the moving platform and the fixed platform based on the pitch angle, roll angle, pitch angular velocity, and roll angular velocity of the moving platform and the fixed platform;

[0021] Calculate the pitch angular acceleration difference between the moving platform and the fixed platform using a PI control algorithm based on the pitch angular acceleration, pitch angle, and pitch angular acceleration of the fixed platform;

[0022] Calculate the roll angular acceleration difference between the moving platform and the fixed platform using a PI control algorithm based on the roll angular acceleration, roll angle, and roll angular velocity of the fixed platform.

[0023] In some embodiments, calculating the vertical error value between the fixed platform and the moving platform based on the vertical velocities of the moving platform and the fixed platform includes:

[0024] Calculate the vertical displacements of the moving platform and the fixed platform and the vertical acceleration of the fixed platform based on the vertical velocities of the moving platform and the fixed platform;

[0025] Calculate the vertical displacement difference and vertical velocity difference between the fixed platform and the moving platform based on the vertical velocities and vertical displacements of the moving platform and the fixed platform;

[0026] Calculate the vertical acceleration difference between the fixed platform and the moving platform using a skyhook damping control algorithm based on the vertical acceleration of the fixed platform, the vertical velocity of the moving platform, the vertical displacement difference, and the vertical velocity difference.

[0027] In some embodiments, performing dynamic modeling on the parallel vibration damping mechanism according to the screw equation to obtain the dynamic model of the parallel vibration damping mechanism includes:

[0028] Perform dynamic modeling on the parallel vibration damping mechanism according to the following formula:

[0029]

[0030] Where, is the driving linear velocity of the connecting mechanism, F is the output force vector of the electric cylinder, F f is the friction force vector of the electric cylinder, is the velocity screw of the first movable connection point, is the force screw of the first movable connection point, is the velocity screw of the second movable connection point, is the force screw of the second movable connection point, T P is the velocity screw of the center point of the moving platform, WP The force screw of the center point of the moving platform;

[0031] According to the formula, combined with the inverse Jacobian matrix, the dynamic model of the parallel damping mechanism is obtained.

[0032] In some embodiments, the step of respectively calculating the screw equations of the center point of the moving platform, the first moving connection point, and the second moving connection point includes:

[0033] Establish a body-fixed coordinate system according to the center point of the fixed platform;

[0034] Calculate the velocity screw equation of the center point of the moving platform according to the velocity and angular velocity of the center point of the moving platform;

[0035] Calculate the force screw equation of the center point of the moving platform according to the unit vector in the telescopic direction of the passive connection mechanism and the acceleration, angular velocity, and angular acceleration of the center point of the moving platform;

[0036] Calculate the angular velocity and driving linear velocity of the active connection mechanism according to the unit vector in the telescopic direction of the active connection structure, the velocity of the center point of the moving platform, the angular velocity of the center point of the moving platform, and the coordinates of the first moving connection point in the body-fixed coordinate system;

[0037] Calculate the angular acceleration of the active connection mechanism according to the angular velocity and driving linear velocity of the active connection mechanism and the acceleration of the center point of the moving platform;

[0038] Calculate the velocity screw equations of the first moving connection point and the second moving connection point according to the velocity of the first moving connection point and the angular velocity of the active connection mechanism;

[0039] Calculate the force screw equations of the first moving connection point and the second moving connection point according to the acceleration of the first moving connection point, the angular velocity of the active connection mechanism, the angular acceleration of the active connection mechanism, the unit vector in the telescopic direction of the active connection mechanism, and the mass parameters of the parallel damping mechanism.

[0040] In some embodiments, after controlling the active connection mechanism according to the control force and adjusting the pose information of the moving platform, it includes:

[0041] Obtain the current pose information of the moving platform in real time;

[0042] Adjust the control force of the driving mechanism according to the pose information of the fixed platform and the current pose information.

[0043] The present invention also provides a control system for a parallel vibration damping mechanism, which is applied to the parallel vibration damping mechanism. The parallel vibration damping mechanism includes a moving platform and a fixed platform. The centers of the moving platform and the fixed platform are connected by a passive connection mechanism. The moving platform is fixedly connected to the passive connection mechanism, and the fixed platform is movably connected to the passive connection mechanism. The four corners of the moving platform and the fixed platform are movably connected by an active connection mechanism, and the active connection mechanism is driven by a driving mechanism, including:

[0044] A first acquisition module, configured to respectively acquire the pose information of the moving platform and the fixed platform, where the pose information includes pitch angular velocity, roll angular velocity, and vertical velocity;

[0045] A first calculation module, configured to respectively calculate the screw equations of the center point of the moving platform, the first movable connection point, and the second movable connection point. The screw equations include a velocity screw equation and a force screw equation. The first movable connection point is the connection point between the driving mechanism and the moving platform, and the second movable connection point is the connection point between the driving mechanism and the fixed platform;

[0046] A second acquisition module, configured to perform dynamic modeling on the parallel vibration damping mechanism according to the screw equations to obtain the dynamic model of the parallel vibration damping mechanism and the connection point between the passive connection mechanism and the fixed platform;

[0047] A second calculation module, configured to calculate the control force of the driving mechanism according to the pose information of the moving platform and the fixed platform and the dynamic model;

[0048] An adjustment module, configured to control the active connection mechanism according to the control force and adjust the pose information of the moving platform.

[0049] In some embodiments, the second calculation module includes:

[0050] A first calculation sub-module, configured to calculate the pitch angle difference, roll angle difference, pitch angular velocity difference, roll angular velocity difference, pitch angular acceleration difference, and roll angular acceleration difference between the fixed platform and the moving platform according to the pitch angular velocity and roll angular velocity of the moving platform and the fixed platform;

[0051] A second calculation sub-module, configured to calculate the vertical error value between the fixed platform and the moving platform according to the vertical velocities of the moving platform and the fixed platform. The vertical error value includes a vertical displacement difference, a vertical velocity difference, and a vertical acceleration difference;

[0052] A third calculation sub-module, configured to substitute the pitch angle difference, roll angle difference, pitch angular velocity difference, roll angular velocity difference, pitch angular acceleration difference, roll angular acceleration difference, and the vertical error value into the dynamic model to calculate the control force of the driving mechanism.

[0053] In some embodiments, the first calculation sub-module includes:

[0054] A first calculation unit, configured to calculate the pitch angle and roll angle of the moving platform and the fixed platform, and the pitch angular acceleration and roll angular acceleration of the fixed platform according to the pitch angular velocity and roll angular velocity of the moving platform and the fixed platform;

[0055] A second calculation unit, configured to calculate the pitch angle difference, roll angle difference, pitch angular velocity difference, and roll angular velocity difference between the moving platform and the fixed platform according to the pitch angle, roll angle, pitch angular velocity, and roll angular velocity of the moving platform and the fixed platform;

[0056] A third calculation unit, configured to calculate the pitch angular acceleration difference between the moving platform and the fixed platform by using a PI control algorithm according to the pitch angular acceleration, pitch angle, and pitch angular acceleration of the fixed platform;

[0057] The third calculation unit is further configured to calculate the roll angular acceleration difference between the moving platform and the fixed platform by using a PI control algorithm according to the roll angular acceleration, roll angle, and roll angular velocity of the fixed platform.

[0058] In some embodiments, the first calculation sub-module includes:

[0059] A first calculation unit, configured to calculate the pitch angle and roll angle of the moving platform and the fixed platform, and the pitch angular acceleration and roll angular acceleration of the fixed platform according to the pitch angular velocity and roll angular velocity of the moving platform and the fixed platform;

[0060] A second calculation unit, configured to calculate the pitch angle difference, roll angle difference, pitch angular velocity difference, and roll angular velocity difference between the moving platform and the fixed platform according to the pitch angle, roll angle, pitch angular velocity, and roll angular velocity of the moving platform and the fixed platform;

[0061] A third calculation unit, configured to calculate the pitch angular acceleration difference between the moving platform and the fixed platform by using a PI control algorithm according to the pitch angular acceleration, pitch angle, and pitch angular acceleration of the fixed platform;

[0062] The third calculation unit is further configured to calculate the roll angular acceleration difference between the moving platform and the fixed platform by using a PI control algorithm according to the roll angular acceleration, roll angle, and roll angular velocity of the fixed platform.

[0063] In some embodiments, the second calculation sub-module includes:

[0064] A fourth calculation unit, configured to calculate the vertical displacement between the moving platform and the fixed platform and the vertical acceleration of the fixed platform according to the vertical velocities of the moving platform and the fixed platform;

[0065] A fifth calculation unit, configured to calculate the vertical displacement difference and the vertical velocity difference between the fixed platform and the moving platform according to the vertical velocities and vertical displacements of the moving platform and the fixed platform;

[0066] A sixth calculation unit, configured to calculate the vertical acceleration difference between the fixed platform and the moving platform by using a skyhook damping control algorithm according to the vertical acceleration of the fixed platform, the vertical velocity of the moving platform, the vertical displacement difference, and the vertical velocity difference.

[0067] Compared with the prior art, the present invention has at least one of the following beneficial effects:

[0068] 1. Based on the torque control of the driving mechanism, the moving platform of the parallel vibration damping mechanism with a hybrid series-parallel main and passive axes is stationary on the plane except for the vertical movement, which can effectively reduce the influence of the load moment of inertia on the instability of the tabletop and reduce power loss.

[0069] 2. By solving the dynamic model of the parallel robot through screw theory, compared with traditional dynamic calculation methods such as the Lagrangian method, the formula of the model is simple and suitable for embedded systems with high real-time requirements.

[0070] 3. By performing PI control on the poses of the pitch angle and roll angle, the anti-rolling performance of the mechanism is ensured. At the same time, since the mechanism itself is in the form of a hybrid series-parallel main and passive axes, the passive axis ensures that there is no horizontal displacement on the upper tabletop, basically ensuring the stability of the vibration damping platform in the horizontal direction. By controlling the vertical acceleration, the acceleration generated by the bottom excitation is greatly reduced, and the vibration damping efficiency is greatly improved;

[0071] 4. The present invention is based on an active vibration damping control algorithm, and its vibration damping effect and stability are better than those of passive vibration damping. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] The above characteristics, technical features, advantages and their implementation manners of the present invention will be further described below in a clear and understandable manner in conjunction with the drawings in the preferred embodiments.

[0073] Figure 1 It is a flowchart of an embodiment of the control method for the parallel vibration damping mechanism of the present invention;

[0074] Figure 2 It is a schematic structural diagram of the parallel vibration damping mechanism of the present invention;

[0075] Figure 3 It is the time-domain curves of the output forces of each electric cylinder under four excitation combinations in an embodiment of the present invention;

[0076] Figure 4 It is the time-domain curve of the output force error of the electric cylinder in an embodiment of the present invention;

[0077] Figure 5 It is the combined simulation result of Adams and Simulink in an embodiment of the present invention;

[0078] Figure 6 It is the block diagram of the control algorithm in an embodiment of the present invention;

[0079] Figure 7 It is the structural block diagram of an embodiment of the control system of the parallel vibration damping mechanism of the present invention.

[0080] Explanation of the reference numerals in the attached drawings:

[0081] The first acquisition module 100, the first calculation module 200, the second acquisition module 300, the second calculation module 400, and the adjustment module 500. Detailed implementation manners

[0082] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the specific implementation manners of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings, and other implementation manners can also be obtained.

[0083] For the sake of simplicity of the drawings, only the parts related to the invention are schematically shown in each drawing, and they do not represent the actual structure of the product. In addition, for the sake of simplicity and easy understanding of the drawings, in some drawings, components with the same structure or function are only schematically shown as one of them, or only one of them is marked. In this document, "one" not only means "only this one", but also means the situation of "more than one".

[0084] It should be further understood that the term "and / or" used in the specification and claims of the present application refers to any combination and all possible combinations of one or more of the related listed items, and includes these combinations.

[0085] In addition, in the description of the present application, terms such as "first" and "second" are only used for distinguishing descriptions and cannot be construed as indicating or implying relative importance.

[0086] The parallel mechanism in the present invention is a closed-loop mechanism driven in a parallel manner, including a moving platform and a fixed platform. The moving platform and the fixed platform are connected by at least two independent kinematic chains and have two or more degrees of freedom.

[0087] In an embodiment of the present invention, as Figure 1 shown, a control method for a parallel vibration damping mechanism is applied to a parallel vibration damping mechanism. The parallel vibration damping mechanism includes a moving platform and a fixed platform. The centers of the moving platform and the fixed platform are connected by a passive connection mechanism. The moving platform is fixedly connected to the passive connection mechanism, and the fixed platform is movably connected to the passive connection mechanism. Moreover, the four corners of the moving platform and the fixed platform are movably connected by active connection mechanisms. The active connection mechanisms are driven by drive mechanisms and include the following steps:

[0088] S100 Obtain the pose information of the moving platform and the fixed platform respectively. The pose information includes pitch angular velocity, roll angular velocity, and vertical velocity;

[0089] Specifically, the pose information of the moving platform and the fixed platform is obtained through sensors. Since there are certain errors and drifts in the data directly measured by the sensors, directly using these data will cause the platform displacement to diverge rapidly. The accurate pose information of the moving platform and the fixed platform can be obtained through complementary filtering.

[0090] S200 Calculate the screw equations of the center point of the moving platform, the first moving connection point, and the second moving connection point respectively. The screw equations include velocity screw equations and force screw equations. The first moving connection point is the connection point between the active connection mechanism and the moving platform, and the second moving connection point is the connection point between the active connection mechanism and the fixed platform and the connection point between the passive connection mechanism and the fixed platform;

[0091] S300 Perform dynamic modeling on the parallel vibration damping mechanism according to the screw equations to obtain the dynamic model of the parallel vibration damping mechanism;

[0092] Specifically, calculate the screw equations of the center point of the moving platform, the first moving connection point, and the second moving connection point respectively. The screw equations include velocity screw equations and force screw equations. According to the calculation results, establish the dynamic model of the parallel vibration damping mechanism.

[0093] S400 Calculate the control force of the drive mechanism according to the pose information of the moving platform and the fixed platform and the dynamic model;

[0094] S500 Control the active connection mechanism according to the control force to adjust the pose information of the moving platform.

[0095] Specifically, the output of each driving mechanism can be calculated through dynamic modeling, and the active connection mechanism is controlled by the output of each driving mechanism to adjust the pose information of the moving platform so as to maintain the balance of the moving platform in different postures.

[0096] In this embodiment, a parallel damping mechanism is adopted, and an accurate dynamic model of the parallel damping mechanism is established. Based on this dynamic model, multi-dimensional attitude control of the damping platform is carried out, which can be applied to a real-time embedded system, improving the reaction speed of the driving mechanism, enabling it to follow the road excitation in a bumpy environment during high-frequency vibration, thus achieving an ideal damping effect; based on the control force of the driving mechanism, the pose information of the moving platform is adjusted, ensuring the stability of the parallel damping mechanism in the horizontal direction and enhancing the damping effect.

[0097] In one embodiment, step S200 includes:

[0098] S210 Establish a body-fixed coordinate system according to the center points of the moving platform and the fixed platform;

[0099] Specifically, as Figure 2 shown, the parallel damping mechanism is of the 4UPS+UP configuration. The four axes between the upper and lower platforms are composed of Hooke joints, motorized cylinders, and spherical joints to form UPS branches (U represents Hooke joint, P represents prismatic pair, S represents spherical joint). The upper part of the central spring damper is fixedly connected to the upper tabletop, and the lower part is connected to the lower tabletop with a Hooke joint to form a UP branch (U represents Hooke joint, P represents prismatic pair).

[0100] The lengths of the four UPS branches are actively controlled by motorized cylinders and serve as active axes, which can control the movement of the upper platform (moving platform) relative to the lower platform (fixed platform) in three independent degrees of freedom; the central UP branch plays a passive damping effect through the spring damper and changes passively according to the distance between the centers of the upper and lower platforms, serving as a passive branch.

[0101] Taking the center point O D of the bottom plate (fixed platform) as the origin and the center point O P of the upper tabletop (moving platform) as the origin, the body-fixed coordinate systems O D X D Y D Z D and O P X P Y P Z P of the fixed platform and the moving platform are established respectively. The hinge points of the four UPS branches on the lower tabletop and the hinge point of the central UP branch on the lower tabletop are marked as D i (i = 1, 2, 3, 4, 5), and the hinge points of the four UPS branches on the upper tabletop are marked as P i(i = 1, 2, 3, 4).

[0102] S220 calculates the velocity screw equation of the center point of the moving platform according to the velocity and angular velocity of the center point of the moving platform.

[0103] Specifically, let the center point O of the moving platform P in the body-fixed coordinate system O D X D Y D Z D have an angular velocity of ωP and a velocity of v P . Using screw theory, according to the following formula, calculate the velocity screw T P of point O P :

[0104]

[0105] where H P is the velocity screw transformation matrix of the center point O of the moving platform P , which transforms the velocity screw of the center point P of the moving platform in the inertial coordinate system into the velocity screw in the body-fixed coordinate system O P X P Y P Z P .

[0106] S230 calculates the force screw equation of the center point of the moving platform according to the unit vector in the telescopic direction of the passive connection mechanism and the acceleration, angular velocity, and angular acceleration of the center point of the moving platform.

[0107] Specifically, using screw theory, according to the following formula, calculate the force screw equation W P of the center point O of the moving platform P :

[0108]

[0109] where s0 is the unit vector in the telescopic direction of the passive connection mechanism, is the acceleration at O P , ω P is the angular velocity at O P , is the angular acceleration at O P , m P is the mass of the upper platform surface, c P is the distance from the center of mass to O P , is the linear parameter of the inertia tensor , G P represents the coefficient matrix in front of the moment of inertia;

[0110] In the above formula,

[0111] G P can be obtained by reverse deduction from the formula, where is the three-dimensional angular velocity vector of the moving platform in the body-fixed coordinate system O X P X P Y P Z P ; is the three-dimensional angular acceleration vector of the moving platform in the coordinate system O P X P Y P Z P .

[0112] S240 calculates the angular velocity and driving linear velocity of the active connection mechanism according to the unit vector in the telescopic direction of the active connection structure, the velocity of the center point of the moving platform, the angular velocity of the center point of the moving platform, and the coordinates of the first active connection point in the body-fixed coordinate system of the fixed platform;

[0113] Specifically, let the angular velocity vector at point O D X D Y D Z D of the moving platform in the body-fixed system O P be ω P , and the angular acceleration vector be Then the velocity of the first active connection point P i can be expressed as:

[0114]

[0115] where v P is the velocity of the center point of the moving platform, b i is the coordinate of the first active connection point P i in the body-fixed coordinate system O D X D Y D Z D , ω i is the angular velocity of the active connection mechanism, l i is the length of the active connection mechanism, is the driving linear velocity of each active connection mechanism, s i = l i / l i is the unit vector in the telescopic direction of each active connection mechanism;

[0116] Taking the dot product and cross product of both sides of the above formula with s i , the driving linear velocity and angular velocity ω i of the active connection mechanism can be obtained:

[0117]

[0118] Screw equation for calculating the first active connection point and the second active connection point.

[0119] S250 calculates the angular acceleration of the active connection mechanism based on the angular velocity and driving linear velocity of the active connection mechanism, and the acceleration of the center point of the moving platform.

[0120] Specifically, by differentiating the velocity of the first active connection point P i , the acceleration of point P i can be obtained:

[0121] Among them, is the acceleration of the center point O D of the fixed platform, is the angular acceleration of point O D , ω D is the angular velocity of point O D , is the displacement vector of the origin O i of the fixed platform body coordinate system under the moving body coordinate system O P X P Y P Z P to the origin O D of the fixed platform body coordinate system, is the angular acceleration of the active connection mechanism, is the driving linear acceleration of the active connection mechanism, l i is the length of the active connection mechanism, is the driving linear velocity of the active connection mechanism, ω i is the angular velocity of the active connection mechanism;

[0122] By dot-multiplying and cross-multiplying both sides of the above formula by s i , the angular acceleration of the active connection mechanism

[0123]

[0124] S260 calculates the velocity screw equation of the first active connection point and the second active connection point according to the velocity of the first active connection point and the angular velocity of the active connection mechanism.

[0125] Specifically, using screw theory, based on the velocity i of point P calculated above and the angular velocity ω i of the active connection mechanism, the velocity screw i of the first active connection point P and the second active connection point D i speed screw

[0126]

[0127]

[0128] wherein, symbol S <x>is an anti-symmetric matrix.

[0129] S270 calculates the force screw equations of the first moving connection point and the second moving connection point according to the acceleration of the first moving connection point, the angular velocity of the active connection mechanism, the angular acceleration of the active connection mechanism, the unit vector in the telescopic direction of the active connection mechanism, and the mass parameters of the parallel vibration damping mechanism.

[0130] Specifically, the mass parameters of the parallel vibration damping mechanism include: the inertia tensor of the upper half of the UPS branch chain about point P i in the body-fixed system Inertia tensor Linear parameters of The mass m of the upper half of each branch chain ui , the distance c from the hinge point of each branch chain to the centroid of the upper half ui , the mass m of the lower half of each branch chain di , the distance c from the lower hinge point of each branch chain to the centroid of the lower half di , the inertia tensor of the lower half of the UPS branch chain about point D i in the body-fixed system Inertia tensor Linear parameters of These mass parameters are obtained in real time during the calculation process.

[0131] Using screw theory, according to the acceleration of point P i calculated above the angular velocity ω of the active connection mechanism i , the angular acceleration of the active connection mechanism the orientation vector s in the telescopic direction of the active connection mechanism i , the force screw equation of the first moving connection point is calculated through the following formula and the force screw equation of the second moving connection point

[0132]

[0133] where g is the gravitational acceleration, m ui is the mass of the upper half of the UPS branch chain, c ui represents the distance from the centroid to P i , is the inertia tensor of the upper half of the UPS branch chain about point P i in the body-fixed system, is the inertia tensor of the linear parameters;

[0134] In the above formula, where, is the three - dimensional angular acceleration vector of the centroid of each cylinder chain with the rotation axis as the x - axis in the joint space of each cylinder chain, is the three - dimensional angular velocity vector of the centroid of each cylinder chain with the rotation axis as the x - axis in the joint space of each cylinder chain, is the three - dimensional angular velocity vector of the centroid of each cylinder chain with the rotation axis as the y - axis in the joint space of each cylinder chain;

[0135]

[0136] In the formula, g is the gravitational acceleration, m di is the mass of the lower part of the UPS chain,, c di represents the distance from the centroid to D i ; is the inertia tensor of the lower part of the UPS chain about point D in the body - fixed frame i ; is the inertia tensor of the linear parameter;

[0137] In this embodiment, through screw theory, each part of the parallel vibration - damping mechanism is decomposed, and the velocity screw equation and force screw equation of each part of the parallel vibration - damping mechanism in the joint space are obtained.

[0138] In one embodiment of the present invention, on the basis of the above - mentioned embodiment, according to the principle of virtual power, the following formula is used to perform dynamic modeling on the parallel vibration - damping mechanism:

[0139]

[0140] Among them, F is the cylinder output force vector, F f is the cylinder friction force vector, is the velocity screw equation of the first moving connection point, is the force screw equation of the first moving connection point, is the velocity screw equation of the second moving connection point, is the force screw equation of the second moving connection point, T P is the velocity screw equation of the center point of the moving platform, W P is the force screw equation of the center point of the moving platform;

[0141] Because the UPS chain has no degree of freedom of spin, so ω i ·s i = 0, and we can get:

[0142]

[0143] According to the above formula and combined with the inverse Jacobian matrix, the dynamic model of the parallel vibration damping mechanism is obtained:

[0144]

[0145]

[0146]

[0147] where J inv is the inverse Jacobian matrix; p di is the mass parameter of the lower half of each branch chain. In general, the magnitudes of these parameters are the same, that is, by default p d = p di . Similarly, it is default that the magnitudes of the mass parameters of the upper half of each branch chain are equal, that is, p u = p ui , and so on.

[0148] As Figure 3 shown, the upper left diagram shows the simulation results of the output forces of the four electric cylinder branch chains when the pitch angle of the lower table is a sine curve with an amplitude of ±6° and a frequency of 0.1 Hz, and the roll angle is a sine curve with an amplitude of ±4° and a frequency of 0.1 Hz; the upper right diagram shows the simulation results of the output forces of the four electric cylinder branch chains when the pitch angle of the lower table is a sine curve with an amplitude of ±3° and a frequency of 0.5 Hz, and the roll angle is a sine curve with an amplitude of ±5° and a frequency of 0.5 Hz; the lower left diagram shows the simulation results of the output forces of the four electric cylinder branch chains when the pitch angle of the lower table is a sine curve with an amplitude of ±3° and a frequency of 0.5 Hz; the lower right diagram shows the simulation results of the output forces of the four electric cylinder branch chains when the pitch angle of the lower table is a sine curve with an amplitude of ±4° and a frequency of 1 Hz, and the roll angle is a sine curve with an amplitude of ±6° and a frequency of 1 Hz.

[0149] In Matlab, equations are constructed according to the above dynamic model, the mass parameters of each part of the parallel mechanism are obtained from Adams, and substituted into the dynamic model. Using the time-domain excitation of four different pitch and roll sine curves, the real-time output forces of the four electric cylinders are calculated. Subtracting the output forces from the Adams simulation results in Figure 3 , the obtained error values are as shown in Figure 4 As shown, the illustration in the upper left corner shows the error between the output force simulation of the four electric cylinder linkages and the calculation result of the dynamic model when the pitch angle of the lower tabletop is a sine curve with an amplitude of ±6° and a frequency of 0.1 Hz, and the roll angle is a sine curve with an amplitude of ±4° and a frequency of 0.1 Hz; the icon in the upper right corner shows the error between the output force simulation of the four electric cylinder linkages and the calculation result of the dynamic model when the pitch angle of the lower tabletop is a sine curve with an amplitude of ±3° and a frequency of 0.5 Hz, and the roll angle is a sine curve with an amplitude of ±5° and a frequency of 0.5 Hz; the illustration in the lower left corner shows the error between the output force simulation of the four electric cylinder linkages and the calculation result of the dynamic model when the pitch angle of the lower tabletop is a sine curve with an amplitude of ±3° and a frequency of 0.5 Hz; the icon in the lower right corner shows the error between the output force simulation of the four electric cylinder linkages and the calculation result of the dynamic model when the pitch angle of the lower tabletop is a sine curve with an amplitude of ±4° and a frequency of 1 Hz, and the roll angle is a sine curve with an amplitude of ±6° and a frequency of 1 Hz.

[0150] It can be seen from Figure 4 that the output force of each electric cylinder can reach up to 350 N at most, and the error is at most no more than 5 N, verifying that the result of the dynamic model is relatively accurate. In this embodiment, by using the virtual power theorem, the sum of the products of the velocity screws and force screws of each part of the parallel vibration damping mechanism is solved and substituted into the Jacobian matrix to complete the dynamic modeling of the parallel mechanism. Compared with traditional dynamic calculation methods such as the Lagrangian method, the formula of the model is concise and suitable for embedded systems with high real-time requirements.

[0151] In one embodiment, step S400 includes:

[0152] S401 Calculate the pitch angle difference, roll angle difference, pitch angular velocity difference, roll angular velocity difference, pitch angular acceleration difference, and roll angular acceleration difference between the fixed platform and the moving platform according to the pitch angular velocity and roll angular velocity of the moving platform and the fixed platform;

[0153] S402 Calculate the vertical error value between the fixed platform and the moving platform according to the vertical velocity of the moving platform and the fixed platform, and the vertical error value includes the vertical displacement difference, vertical velocity difference, and vertical acceleration difference;

[0154] S403 Substitute the pitch angle difference, roll angle difference, pitch angular velocity difference, roll angular velocity difference, pitch angular acceleration difference, roll angular acceleration difference, and vertical error value into the dynamic model to calculate the control force of the driving mechanism.

[0155] In this embodiment, the pose error values of the fixed platform and the moving platform in the three degrees of freedom of pitch, roll, and vertical direction are calculated through the pitch angular velocity, roll angular velocity, and vertical velocity of the moving platform and the fixed platform. These pose error values are substituted into the dynamic model of the parallel damping mechanism to calculate the control force of the driving mechanism, so that the active connection mechanism maintains the balance of the moving platform according to the control force.

[0156] In one embodiment, step S400 includes:

[0157] S410 calculates the pitch angles and roll angles of the moving platform and the fixed platform, as well as the pitch angular acceleration and roll angular acceleration of the fixed platform, according to the pitch angular velocity and roll angular velocity of the moving platform and the fixed platform;

[0158] Specifically, the pitch angular velocity of the moving platform is obtained through a sensor The roll angular velocity of the moving platform The pitch angular velocity of the fixed platform The roll angular velocity of the fixed platform After integrating with respect to time, the pitch angle α of the moving platform is obtained P 、The roll angle β of the moving platform P 、The pitch angle α of the fixed platform D 、The roll angle β of the fixed platform D , and after differentiating with respect to time, the pitch angular acceleration of the fixed platform is obtained The roll angular acceleration of the fixed platform

[0159] S411 calculates the pitch angle difference, roll angle difference, pitch angular velocity difference, and roll angular velocity difference between the moving platform and the fixed platform according to the pitch angles, roll angles, pitch angular velocities, and roll angular velocities of the moving platform and the fixed platform;

[0160] S412 calculates the pitch angular acceleration difference between the moving platform and the fixed platform by using the PI control algorithm according to the pitch angular acceleration, pitch angle, and pitch angular acceleration of the fixed platform;

[0161] S413 calculates the roll angular acceleration difference between the moving platform and the fixed platform by using the PI control algorithm according to the roll angular acceleration, roll angle, and roll angular velocity of the fixed platform;

[0162] Specifically, in order to maintain the balance of the moving platform, the mechanism needs to be able to compensate for the angles α D ,β D in the pitch and roll angle directions of the fixed platform at this time. It is necessary to control the angular velocity of the mechanism rotation and -α P ,-β P The angle tends to 0 to ensure the balance of the upper platform;

[0163] Through PI control, we set:

[0164]

[0165]

[0166] where k α 、k β 、c α 、c β are PI control parameters.

[0167] S414 calculates the vertical displacements of the moving platform and the fixed platform and the vertical acceleration of the fixed platform according to the vertical velocities of the moving platform and the fixed platform;

[0168] Specifically, the vertical velocity of the moving platform is obtained through a sensor and the vertical velocity of the fixed platform The vertical displacements z P 、z D of the moving platform and the fixed platform are respectively obtained by integrating with respect to time, and the vertical acceleration of the fixed platform is obtained by differentiating with respect to time

[0169] S415 calculates the vertical displacement difference and the vertical velocity difference between the fixed platform and the moving platform according to the vertical velocities and vertical displacements of the moving platform and the fixed platform;

[0170] S416 calculates the vertical acceleration difference between the fixed platform and the moving platform by using the skyhook damping control algorithm according to the vertical acceleration of the fixed platform, the vertical velocity of the moving platform, the vertical displacement difference and the vertical velocity difference;

[0171] Specifically, the vertical error value is calculated through the skyhook damping algorithm:

[0172]

[0173]

[0174] where k z 、c z 、s z are skyhook damping control parameters.

[0175] S417 substitutes the pitch angle difference, the roll angle difference, the pitch angular velocity difference, the roll angular velocity difference, the pitch angular acceleration difference, the roll angular acceleration difference and the vertical error value into the dynamic model to calculate the control force of the driving mechanism;

[0176] Specifically, the calculated Δα, Δβ, Δz, are substituted into the dynamic model Φ of the aforementioned parallel vibration damping mechanism, and according to the formula the control force of the drive mechanism is calculated, facilitating the drive mechanism to control the active connection mechanism according to this control force and driving the active connection mechanism to adjust the balance of the moving platform.

[0177] In the co-simulation of Adams and Simulink, the excitation of the fixed platform adopts the combination of pitch, roll excitation and vertical excitation received at the center of the vehicle body chassis when the vehicle is traveling at a speed of 30 km / h on a Class D road surface generated by the white noise method. The above method is used to control the parallel vibration damping mechanism, and the simulation results are as Figure 5 shown. The vertical acceleration decreases from the peak vertical acceleration of the fixed platform of 3.5 m / s 2 to the peak vertical acceleration of the moving platform of 0.6 m / s 2 , a reduction of about 80%; at the same time, the pitch angle and roll angle decrease from 2° and 3° of the fixed platform to 0.05° and 0.1° of the moving platform surface. Therefore, it is considered that this solution can greatly improve the vibration damping efficiency.

[0178] The control algorithm block diagram in this embodiment is as Figure 6 shown. By performing PI control on the poses of the pitch angle and roll angle, the anti-rolling performance of the mechanism is ensured; by performing skyhook damping control on the vertical acceleration, the acceleration generated by the bottom surface excitation is greatly reduced, and the vibration damping efficiency is greatly improved.

[0179] In one embodiment, on the basis of the above embodiment, after step S500, it includes:

[0180] S600 obtains the current pose information of the moving platform in real time;

[0181] S700 adjusts the control force of the drive mechanism according to the pose information of the fixed platform and the current pose information.

[0182] In this embodiment, the control force of the drive mechanism can be calculated according to the current pose information of the moving platform, and the pose of the moving platform can be controlled in real time according to this control force.

[0183] In one embodiment of the present invention, as Figure 7 As shown in the figure, a parallel vibration damping mechanism control system is applied to a parallel vibration damping mechanism. The parallel vibration damping mechanism includes a moving platform and a fixed platform. The centers of the moving platform and the fixed platform are connected by a passive connection mechanism. The moving platform is fixedly connected to the passive connection mechanism, and the fixed platform is movably connected to the passive connection mechanism. The four corners of the moving platform and the fixed platform are movably connected by an active connection mechanism. The active connection mechanism is driven by a driving mechanism, and includes a first acquisition module 100, a first calculation module 200, a second acquisition module 300, a second calculation module 400, and an adjustment module 500. Among them:

[0184] The first acquisition module 100 is used to respectively acquire the pose information of the moving platform and the fixed platform. The pose information includes pitch angular velocity, roll angular velocity, and vertical velocity;

[0185] The first calculation module 200 is used to respectively calculate the screw equations of the center point of the moving platform, the first moving connection point, and the second moving connection point. The screw equations include a velocity screw equation and a force screw equation. The first moving connection point is the connection point between the driving mechanism and the moving platform, and the second moving connection point is the connection point between the driving mechanism and the fixed platform and the connection point between the passive connection mechanism and the fixed platform;

[0186] The second acquisition module 300 is used to perform dynamic modeling on the parallel vibration damping mechanism according to the screw equation to obtain the dynamic model of the parallel vibration damping mechanism;

[0187] The second calculation module 400 is used to calculate the control force of the driving mechanism according to the pose information of the moving platform and the fixed platform and the dynamic model;

[0188] The adjustment module 500 is used to control the active connection mechanism according to the control force and adjust the pose information of the moving platform.

[0189] In one embodiment, the second calculation module includes a first calculation sub-module, a second calculation sub-module, and a third calculation sub-module. Among them:

[0190] The first calculation sub-module is used to calculate the pitch angle difference, roll angle difference, pitch angular velocity difference, roll angular velocity difference, pitch angular acceleration difference, and roll angular acceleration difference between the fixed platform and the moving platform according to the pitch angular velocity and roll angular velocity of the moving platform and the fixed platform;

[0191] The second calculation sub-module is used to calculate the vertical error value between the fixed platform and the moving platform according to the vertical velocities of the moving platform and the fixed platform. The vertical error value includes vertical displacement difference, vertical velocity difference, and vertical acceleration difference;

[0192] A third calculation sub-module, configured to substitute the pitch angle difference, roll angle difference, pitch angular velocity difference, roll angular velocity difference, pitch angular acceleration difference, roll angular acceleration difference, and the vertical error value into the dynamic model to calculate the control force of the driving mechanism.

[0193] In one embodiment, the first calculation sub-module includes a first calculation unit, a second calculation unit, and a third calculation unit, where:

[0194] The first calculation unit is configured to calculate the pitch angle and roll angle of the moving platform and the fixed platform, and the pitch angular acceleration and roll angular acceleration of the fixed platform according to the pitch angular velocity and roll angular velocity of the moving platform and the fixed platform;

[0195] The second calculation unit is configured to calculate the pitch angle difference, roll angle difference, pitch angular velocity difference, and roll angular velocity difference between the moving platform and the fixed platform according to the pitch angle, roll angle, pitch angular velocity, and roll angular velocity of the moving platform and the fixed platform;

[0196] The third calculation unit is configured to calculate the pitch angular acceleration difference between the moving platform and the fixed platform by using a PI control algorithm according to the pitch angular acceleration, pitch angle, and pitch angular acceleration of the fixed platform;

[0197] The third calculation unit is further configured to calculate the roll angular acceleration difference between the moving platform and the fixed platform by using a PI control algorithm according to the roll angular acceleration, roll angle, and roll angular velocity of the fixed platform.

[0198] In one embodiment, the second calculation sub-module includes a fourth calculation unit, a fifth calculation unit, and a sixth calculation unit, where:

[0199] The fourth calculation unit is configured to calculate the vertical displacement of the moving platform and the fixed platform and the vertical acceleration of the fixed platform according to the vertical velocity of the moving platform and the fixed platform;

[0200] The fifth calculation unit is configured to calculate the vertical displacement difference and vertical velocity difference between the fixed platform and the moving platform according to the vertical velocity and vertical displacement of the moving platform and the fixed platform;

[0201] The sixth calculation unit is configured to calculate the vertical acceleration difference between the fixed platform and the moving platform by using a skyhook damping control algorithm according to the vertical acceleration of the fixed platform, the vertical velocity of the moving platform, the vertical displacement difference, and the vertical velocity difference.

[0202] It should be noted that the embodiments of the parallel vibration damping mechanism control system provided by the present invention and the embodiments of the parallel vibration damping mechanism control method provided above are all based on the same inventive concept and can achieve the same technical effects. Therefore, other specific contents of the embodiments of the parallel vibration damping mechanism control system can refer to the descriptions of the contents of the embodiments of the parallel vibration damping mechanism control method above.

[0203] It should be noted that the above embodiments can be freely combined as needed. The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.< / x>

Claims

1. A control method for a parallel vibration damping mechanism, characterized in that Applied to a parallel vibration damping mechanism, the parallel vibration damping mechanism includes a moving platform and a fixed platform. The centers of the moving platform and the fixed platform are connected by a passive connection mechanism. The moving platform is fixedly connected to the passive connection mechanism, and the fixed platform is movably connected to the passive connection mechanism. Moreover, the four corners of the moving platform and the fixed platform are movably connected by active connection mechanisms, and the active connection mechanisms are driven by a driving mechanism, including: Respectively obtain the pose information of the moving platform and the fixed platform, where the pose information includes pitch angular velocity, roll angular velocity, and vertical velocity; Respectively calculate the screw equations of the center point of the moving platform, the first moving connection point, and the second moving connection point. The screw equations include a velocity screw equation and a force screw equation. The first moving connection point is the connection point between the active connection mechanism and the moving platform, and the second moving connection point is the connection point between the active connection mechanism and the fixed platform and the connection point between the passive connection mechanism and the fixed platform; According to the screw equations, perform dynamic modeling on the parallel vibration damping mechanism to obtain the dynamic model of the parallel vibration damping mechanism; According to the pose information of the moving platform and the fixed platform and the dynamic model, calculate the control force of the driving mechanism; Control the active connection mechanism according to the control force to adjust the pose information of the moving platform; Among them, the performing dynamic modeling on the parallel vibration damping mechanism according to the screw equations to obtain the dynamic model of the parallel vibration damping mechanism includes: Perform dynamic modeling on the parallel vibration damping mechanism according to the following formula: ; Wherein, is the driving linear velocity of the connecting mechanism, is the output force vector of the electric cylinder, is the friction force vector of the electric cylinder, is the velocity screw of the first movable connection point, is the force screw of the first movable connection point, is the velocity screw of the second movable connection point, is the force screw of the second movable connection point, is the velocity screw of the center point of the moving platform, is the force screw of the center point of the moving platform; According to the formula, combined with the inverse Jacobian matrix, obtain the dynamic model of the parallel vibration damping mechanism.

2. The control method of a parallel vibration damping mechanism according to claim 1, wherein, The calculating the control force of the driving mechanism according to the pose information and the dynamic model includes: According to the pitch angular velocity and roll angular velocity of the moving platform and the fixed platform, calculate the pitch angle difference, roll angle difference, pitch angular velocity difference, roll angular velocity difference, pitch angular acceleration difference, and roll angular acceleration difference between the fixed platform and the moving platform; According to the vertical velocities of the moving platform and the fixed platform, calculate the vertical error value between the fixed platform and the moving platform. The vertical error value includes vertical displacement difference, vertical velocity difference, and vertical acceleration difference; Substitute the pitch angle difference, roll angle difference, pitch angular velocity difference, roll angular velocity difference, pitch angular acceleration difference, roll angular acceleration difference, and vertical error value into the dynamic model to calculate the control force of the driving mechanism.

3. The control method of a parallel vibration damping mechanism according to claim 2, wherein The calculating the pitch angle difference, roll angle difference, pitch angular velocity difference, roll angular velocity difference, pitch angular acceleration difference, and roll angular acceleration difference between the fixed platform and the moving platform according to the pitch angular velocity and roll angular velocity of the moving platform and the fixed platform includes: According to the pitch angular velocity and roll angular velocity of the moving platform and the fixed platform, calculate the pitch angle and roll angle of the moving platform and the fixed platform, and the pitch angular acceleration and roll angular acceleration of the fixed platform; Calculate the pitch angle difference, roll angle difference, pitch angular velocity difference, and roll angular velocity difference between the moving platform and the fixed platform based on the pitch angle, roll angle, pitch angular velocity, and roll angular velocity of the moving platform and the fixed platform; Calculate the pitch angular acceleration difference between the moving platform and the fixed platform using a PI control algorithm based on the pitch angular acceleration, pitch angle, and pitch angular velocity of the fixed platform; Calculate the roll angular acceleration difference between the moving platform and the fixed platform using a PI control algorithm based on the roll angular acceleration, roll angle, and roll angular velocity of the fixed platform.

4. The control method of a parallel vibration damping mechanism according to claim 2, characterized in that The calculating the vertical error value between the fixed platform and the moving platform according to the vertical velocities of the moving platform and the fixed platform includes: Calculate the vertical displacements of the moving platform and the fixed platform and the vertical acceleration of the fixed platform based on the vertical velocities of the moving platform and the fixed platform; Calculate the vertical displacement difference and vertical velocity difference between the fixed platform and the moving platform based on the vertical velocities and vertical displacements of the moving platform and the fixed platform; Calculate the vertical acceleration difference between the fixed platform and the moving platform using a skyhook damping control algorithm based on the vertical acceleration of the fixed platform, the vertical velocity of the moving platform, the vertical displacement difference, and the vertical velocity difference.

5. The control method of a parallel vibration damping mechanism according to claim 1, characterized in that The separately calculating the screw equations of the center point, the first movable connection point, and the second movable connection point of the moving platform includes: Establish a body-fixed coordinate system based on the center point of the fixed platform; Calculate the velocity screw equation of the center point of the moving platform based on the velocity and angular velocity of the center point of the moving platform; Calculate the force screw equation of the center point of the moving platform based on the unit vector in the telescopic direction of the passive connection mechanism and the acceleration, angular velocity, and angular acceleration of the center point of the moving platform; Calculate the angular velocity and driving linear velocity of the active connection mechanism based on the unit vector in the telescopic direction of the active connection structure, the velocity of the center point of the moving platform, the angular velocity of the center point of the moving platform, and the coordinates of the first movable connection point in the body-fixed coordinate system; Calculate the angular acceleration of the active connection mechanism based on the angular velocity and driving linear velocity of the active connection mechanism and the acceleration of the center point of the moving platform; Calculate the velocity screw equations of the first movable connection point and the second movable connection point based on the velocity of the first movable connection point and the angular velocity of the active connection mechanism; Calculate the force screw equations of the first movable connection point and the second movable connection point based on the acceleration of the first movable connection point, the angular velocity of the active connection mechanism, the angular acceleration of the active connection mechanism, the unit vector in the telescopic direction of the active connection mechanism, and the mass parameters of the parallel vibration damping mechanism.

6. The control method of a parallel vibration damping mechanism according to any one of claims 1-5, characterized in that, After controlling the active connection mechanism according to the control force and adjusting the pose information of the moving platform, the following steps are included: Real-time obtain the current pose information of the moving platform; Adjust the control force of the driving mechanism according to the pose information of the fixed platform and the current pose information.

7. A parallel vibration damping mechanism control system, characterized in that, Applied to a parallel vibration damping mechanism, the parallel vibration damping mechanism includes a moving platform and a fixed platform. The centers of the moving platform and the fixed platform are connected by a passive connection mechanism. The moving platform is fixedly connected to the passive connection mechanism, and the fixed platform is movably connected to the passive connection mechanism. Moreover, the four corners of the moving platform and the fixed platform are movably connected by active connection mechanisms, and the active connection mechanisms are driven by a driving mechanism, including: A first acquisition module, configured to respectively acquire the pose information of the moving platform and the fixed platform, where the pose information includes pitch angular velocity, roll angular velocity, and vertical velocity; A first calculation module, configured to respectively calculate the screw equations of the center point of the moving platform, the first moving connection point, and the second moving connection point. The screw equations include a velocity screw equation and a force screw equation. The first moving connection point is the connection point between the driving mechanism and the moving platform, and the second moving connection point is the connection point between the driving mechanism and the fixed platform and the connection point between the passive connection mechanism and the fixed platform; A second acquisition module, configured to perform dynamic modeling on the parallel vibration damping mechanism according to the screw equations to obtain a dynamic model of the parallel vibration damping mechanism; A second calculation module, configured to calculate the control force of the driving mechanism according to the pose information of the moving platform and the fixed platform and the dynamic model; An adjustment module, configured to control the active connection mechanism according to the control force and adjust the pose information of the moving platform; Wherein, the second acquisition module performs dynamic modeling on the parallel vibration damping mechanism according to the following formula: ; wherein, is the driving linear velocity of the connecting mechanism, is the output force vector of the electric cylinder, is the frictional force vector of the electric cylinder, is the velocity screw of the first movable connection point, is the force screw of the first movable connection point, is the velocity screw of the second movable connection point, is the force screw of the second movable connection point, is the velocity screw of the center point of the moving platform, is the force screw of the center point of the moving platform; According to the formula, combined with the inverse Jacobian matrix, a dynamic model of the parallel vibration damping mechanism is obtained.

8. The control system of a parallel vibration damping mechanism according to claim 7, characterized in that, The second calculation module includes: A first calculation sub-module, configured to calculate the pitch angle difference, roll angle difference, pitch angular velocity difference, roll angular velocity difference, pitch angular acceleration difference, and roll angular acceleration difference between the fixed platform and the moving platform according to the pitch angular velocity and roll angular velocity of the moving platform and the fixed platform; A second calculation sub-module, configured to calculate the vertical error value between the fixed platform and the moving platform according to the vertical velocities of the moving platform and the fixed platform. The vertical error value includes a vertical displacement difference, a vertical velocity difference, and a vertical acceleration difference; A third calculation sub-module, configured to substitute the pitch angle difference, roll angle difference, pitch angular velocity difference, roll angular velocity difference, pitch angular acceleration difference, roll angular acceleration difference, and the vertical error value into the dynamic model to calculate the control force of the driving mechanism.

9. The control system of a parallel vibration damping mechanism according to claim 8, characterized in that, The first calculation sub-module includes: A first calculation unit, configured to calculate the pitch angle and roll angle of the moving platform and the fixed platform and the pitch angular acceleration and roll angular acceleration of the fixed platform according to the pitch angular velocity and roll angular velocity of the moving platform and the fixed platform; A second calculation unit, configured to calculate the pitch angle difference, roll angle difference, pitch angular velocity difference, and roll angular velocity difference between the moving platform and the fixed platform according to the pitch angle, roll angle, pitch angular velocity, and roll angular velocity of the moving platform and the fixed platform; A third calculation unit, configured to calculate a pitch angular acceleration difference between the moving platform and the fixed platform by using a PI control algorithm according to the pitch angular acceleration, pitch angle, and pitch angular acceleration of the fixed platform; The third calculation unit is further configured to calculate a roll angular acceleration difference between the moving platform and the fixed platform by using a PI control algorithm according to the roll angular acceleration, roll angle, and roll angular velocity of the fixed platform.

10. The control system of a parallel vibration damping mechanism according to claim 8, characterized in that, The second calculation sub-module includes: A fourth calculation unit, configured to calculate a vertical displacement between the moving platform and the fixed platform and a vertical acceleration of the fixed platform according to the vertical velocities of the moving platform and the fixed platform; A fifth calculation unit, configured to calculate a vertical displacement difference and a vertical velocity difference between the fixed platform and the moving platform according to the vertical velocities and vertical displacements of the moving platform and the fixed platform; A sixth calculation unit, configured to calculate a vertical acceleration difference between the fixed platform and the moving platform by using a skyhook damping control algorithm according to the vertical acceleration of the fixed platform, the vertical velocity of the moving platform, the vertical displacement difference, and the vertical velocity difference.

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