Cable parallel robot vibration suppression control device and method

Abstract

The application provides a vibration suppression control device and method for a cable parallel robot, and a low-frequency vibration suppression system and a high-frequency vibration suppression system are respectively designed for low-frequency and large-amplitude vibration in an under-constrained direction and high-frequency and small-amplitude vibration in a constrained direction, and a corresponding vibration suppression control method is provided.The device comprises the low-frequency vibration suppression system, the high-frequency vibration suppression system, a sensing system and a control system.By mounting the low-frequency vibration suppression system and the high-frequency vibration suppression system on a moving platform of the cable parallel robot, corresponding vibration suppression forces are output to the moving platform, vibration energy of the moving platform of the cable parallel robot is dissipated, and the terminal precision and stability of the cable parallel robot during operation are effectively improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of cable parallel robots, and particularly relates to a cable parallel robot vibration suppression control device and method, so as to suppress the vibration of the moving platform of the cable parallel robot during operation, and improve the motion accuracy and stability of the cable parallel robot. BACKGROUND

[0002] The cable parallel robot uses a cable instead of a rigid branch chain, and has simple structure, low cost, lower inertia, and can realize a large workspace at a lower cost, and has been widely used in ship painting, large equipment hoisting and other fields. However, because the stiffness of the cable is lower than that of the rigid branch chain, the robot is more easily vibrated by various internal and external disturbances during operation, resulting in reduced end motion accuracy or even loss of control.

[0003] The cable parallel robot uses a cable instead of a rigid branch chain, and is easily vibrated by various internal and external disturbances, and the typical vibration mainly includes two types. One is the free vibration in the under-constrained degree of freedom, and the vibration characteristics are that the frequency is low, the amplitude is large, and the vibration energy is not easy to dissipate, and the key of the vibration suppression control is to realize the continuous dissipation of the vibration energy. The other is the elastic vibration in the constrained degree of freedom, and the vibration characteristics are that the frequency is high, the amplitude is small, and the vibration energy is continuously dissipated due to the elasticity and damping of the cable, and the key of the vibration suppression control is to quickly suppress the amplitude.

[0004] The traditional vibration suppression control of the cable parallel robot is usually implemented by controlling the winding and unwinding of the existing cable of the cable parallel robot. Due to the hysteresis effect of the cable, such method has poor effect when the cable is long or the elastic coefficient is low, and the vibration suppression effect on the under-constrained degree of freedom is limited. SUMMARY

[0005] In order to overcome the problems existing in the prior art, the present application aims at the vibration suppression control of the cable parallel robot, and provides a cable parallel robot vibration suppression control device and method. By installing an active vibration suppression device on the moving platform of the cable parallel robot, the vibration suppression device outputs a vibration suppression force to the moving platform, so that the vibration of the moving platform of the cable parallel robot can be quickly suppressed, thereby effectively improving the motion accuracy and stability of the cable parallel robot.

[0006] In order to achieve the above purpose, the technical scheme adopted by the present application is as follows:

[0007] A cable parallel robot vibration suppression control device, comprising: a low-frequency vibration suppression system 2, a high-frequency vibration suppression system 3, a sensing system 4, and a control system 5, and the action object of the vibration suppression control device is the moving platform 12 of the cable parallel robot 1.

[0008] The low-frequency vibration suppression system 2, the high-frequency vibration suppression system 3 and the sensing system 4 are installed on the moving platform 12 of the cable parallel robot, and the control system 5 is installed on the moving platform 12 of the cable parallel robot or integrated into a control cabinet of the cable parallel robot, and the control system 5 communicates with the low-frequency vibration suppression system 2, the high-frequency vibration suppression system 3 and the sensing system 4 through a cable or wireless signal.

[0009] The low-frequency vibration suppression system 2 comprises a vibration suppression rotor 24, a rotor adjusting rod 23, a direction adjusting motor 22 and a base 21. The base 21 is fixedly connected to the moving platform 12 of the cable parallel robot, the direction adjusting motor 22 is installed on the base 21, the rotor adjusting rod 23 is connected to a motor shaft of the direction adjusting motor 22, and the vibration suppression rotor 24 is fixedly connected to the rotor adjusting rod 23. The vibration suppression rotor 24 and the direction adjusting motor 22 communicate with the control system 5 through a signal cable or a wireless signal. The low-frequency vibration suppression system 2 continuously works on the moving platform 12 through high-speed rotation of the vibration suppression rotor 24, so as to dissipate vibration energy of the moving platform and continuously suppress low-frequency and large-amplitude vibration of the moving platform. Meanwhile, the direction adjusting motor 22 drives the rotor adjusting rod 23 to rotate, so as to adjust the direction of the vibration suppression rotor 24 and the direction of the rotor vibration suppression force. The advantage of the low-frequency vibration suppression system is that it can continuously output the vibration suppression force to the moving platform, and the disadvantage is that the response rate is relatively low.

[0010] The low-frequency vibration suppression system can adjust the direction of the vibration suppression rotor 24 through the direction adjusting motor 22, so as to adjust the direction of the rotor vibration suppression force. When the moving platform 12 has multiple degrees of freedom that need to be vibration suppressed, if the degrees of freedom are not easy to vibrate simultaneously, one set of low-frequency vibration suppression systems can be used to suppress vibration of multiple degrees of freedom. When vibration occurs in a certain degree of freedom, the direction adjusting motor 22 controls the rotor adjusting rod 23 and the vibration suppression rotor 24 to rotate to the corresponding degree of freedom, so as to perform the vibration suppression task. When vibration does not occur in the degree of freedom and vibration occurs in the remaining degrees of freedom, the direction adjusting motor controls the rotor adjusting rod 23 and the vibration suppression rotor 24 to rotate to the degree of freedom where vibration occurs, so as to perform the corresponding vibration suppression task.

[0011] The high-frequency vibration suppression system 3 comprises a mass vibration suppression system 31, a flywheel vibration suppression system 32 and a pendulum vibration suppression system 33.

[0012] The mass damper system 31 comprises a damper mass 314, a slide rail 313, a slide rail motor 312 and a mass damper base 311; the mass damper base 311 is fixedly connected to the moving platform 12 of the cable parallel robot, the slide rail 313 is installed on the mass damper base 311, the damper mass 314 is driven by the slide rail motor 312 and can slide on the slide rail, the slide rail motor 312 communicates with the control system 5 through a signal cable or wireless signal; when the damper control needs to be implemented, the slide rail motor 312 drives the damper mass 314 to make accelerated motion along the slide rail 313, so as to generate a larger instantaneous reaction force and realize the suppression of high-frequency and small-amplitude instantaneous vibration of the moving platform.

[0013] The flywheel damper system 32 comprises a damper flywheel 323, a flywheel motor 322 and a flywheel damper base 321; the flywheel damper base 321 is fixedly connected to the moving platform 12 of the cable parallel robot, the flywheel motor 322 is installed on the flywheel damper base 321, the damper flywheel 323 is connected to the motor shaft of the flywheel motor 322, and the flywheel motor 322 communicates with the control system 5 through a signal cable or wireless signal; when the damper control needs to be implemented, the flywheel motor 322 drives the damper flywheel 323 to rotate at a high speed, so as to generate a larger instantaneous reaction torque and realize the suppression of high-frequency and small-amplitude instantaneous vibration of the moving platform.

[0014] The pendulum damper system 33 comprises a damper pendulum 333, a pendulum motor 332 and a pendulum damper base 331; the pendulum damper base 331 is fixedly connected to the moving platform 12 of the cable parallel robot, the pendulum motor 332 is installed on the pendulum damper base 331, the damper pendulum 333 is connected to the motor shaft of the pendulum motor 332, and the pendulum motor 332 communicates with the control system 5 through a signal cable or wireless signal; when the damper control needs to be implemented, the pendulum motor 332 drives the damper pendulum 333 to perform accelerated swing, so as to generate a larger instantaneous reaction force and realize the suppression of high-frequency and small-amplitude instantaneous vibration of the moving platform.

[0015] The high-frequency damper system has the advantages of fast response speed and the disadvantages of relying on inertial force generated by acceleration and deceleration to damp vibration and being capable of outputting damping force only in a short time. The mass damper system 31 is used to suppress the vibration mode mainly in translation, the flywheel damper system 32 is used to suppress the vibration mode mainly in rotation, and the pendulum damper system 33 can suppress the vibration mode mainly in translation and the vibration mode mainly in rotation.

[0016] The sensing system 4 is internally provided with an acceleration sensor and a gyroscope, is installed on the moving platform of the cable parallel robot, communicates with the control system 5 through a signal cable or wireless signal, is used to measure the acceleration and angular velocity information of the moving platform and is transmitted back to the control system 5.

[0017] The control system 5 is installed on the moving platform of the cable parallel robot or integrated into the cable parallel robot control cabinet, used for receiving the signals transmitted by the sensing system 4, and controlling the low-frequency vibration suppression system 2 and the high-frequency vibration suppression system 3 to perform various vibration suppression control motions.

[0018] Preferably, the transmission mode of the slide rail motor 312 driving the vibration suppression mass 314 is a belt wheel, a chain wheel, a screw guide rail, or a linear motor is used as a slide rail motor to directly drive the vibration suppression mass to move.

[0019] Based on the proposed cable parallel robot vibration suppression control device, a cable parallel robot vibration suppression control method is proposed to realize the suppression of the vibration of the moving platform of the cable parallel robot. The main process of the vibration suppression control method is as follows:

[0020] Step one: through elastic dynamics modeling and modal analysis of the cable parallel robot, the typical vibration form and natural frequency size of the cable parallel robot are determined; or through excitation experiment, the typical vibration form and natural frequency size of the cable parallel robot are determined; according to the characteristics of each mode, the corresponding threshold value is set, when the vibration speed and angular velocity of the cable parallel robot is greater than the threshold value, the vibration suppression control device will be started to implement vibration suppression, otherwise the vibration suppression control device will not be started;

[0021] Step two: according to the analysis results of the natural frequency, the vibration suppression control device is arranged at the corresponding position of the moving platform of the cable parallel robot; for the modes on the under-constrained degrees of freedom of the cable parallel robot, the low-frequency vibration suppression system 2 is preferentially installed in the vibration direction; for the modes on the constrained degrees of freedom of the cable parallel robot, the high-frequency vibration suppression system 3 is preferentially installed in the vibration direction;

[0022] Step three: the sensing system 4 continuously detects the acceleration and angular velocity of the moving platform 12 of the cable parallel robot, and compares it with the theoretical acceleration and angular velocity of the cable parallel robot, and after low-pass filtering, it is identified whether the moving platform 12 exists vibration; if the moving platform 12 exists vibration, the acceleration and angular velocity direction and size corresponding to the vibration amount are solved; in addition, the acceleration signal is integrated and high-pass filtered in the control system 5 to obtain the moving platform speed signal;

[0023] Step four: judge the vibration type of the moving platform, if the acceleration and angular velocity of the moving platform appear on the under-constrained degrees of freedom, the corresponding low-frequency vibration suppression system 2 is mobilized to implement vibration suppression; if the acceleration and angular velocity of the moving platform appear on the constrained degrees of freedom, the corresponding high-frequency vibration suppression system 3 is mobilized to implement vibration suppression;

[0024] For the vibration that needs to be suppressed by the low-frequency vibration suppression system 2, the suppression control of such vibration focuses on continuous dissipation of vibration energy; for such vibration, according to the direction of the vibration velocity signal, the direction-changing motor 22 is controlled to rotate so that the force direction of the vibration suppression rotor 24 is opposite to the vibration velocity direction, and then the vibration suppression rotor 24 rotates at high speed to continuously output the vibration suppression force to the moving platform, so as to realize continuous dissipation of vibration energy.

[0025] For the vibration that needs to be suppressed by the high-frequency vibration suppression system 3, the suppression control of such vibration focuses on quickly offsetting the generated vibration suppression force and vibration acceleration to reduce the amplitude; for such vibration, according to the direction of the vibration acceleration signal, the motor driving the vibration suppression mass block 314, the vibration suppression flywheel 323 or the vibration suppression pendulum 333 in the corresponding direction is controlled to perform acceleration and deceleration movement, so that the high-frequency vibration suppression system 3 generates an inertial force or an inertial torque in the direction opposite to the acceleration signal, thereby realizing suppression of the vibration.

[0026] Step five: during the vibration suppression process, the acceleration and angular velocity of the moving platform of the cable parallel robot are continuously detected, and the velocity signal is obtained by integrating the acceleration; it is continuously judged whether the vibration velocity and angular velocity of the cable parallel robot are greater than the threshold value, and when the velocity and angular velocity of the cable parallel robot on the corresponding mode are less than the threshold value, the vibration suppression control system stops working.

[0027] When arranging the vibration suppression control device for different cable parallel robots, the modes that need to be suppressed can be selected according to the typical modal characteristics of the robot and the characteristics of the working environment, and then different types, quantities and layouts of the low-frequency vibration suppression system 2 and / or the high-frequency vibration suppression system 3 are selected. On the same degree of freedom, multiple low-frequency vibration suppression systems 2 and / or high-frequency vibration suppression systems 3 of the same type or different types can be selected and arranged, and more comprehensive vibration suppression control effect can be achieved through cooperation of multiple vibration suppression devices. For example, multiple low-frequency vibration suppression systems are configured to realize greater continuous vibration suppression force, and low-frequency and high-frequency vibration suppression systems are configured at the same time to realize the compromise between response speed and continuous vibration suppression effect.

[0028] In addition, the use scenarios of the high-frequency vibration suppression system and the low-frequency vibration suppression system are not strictly limited by the type of the degree of freedom of the cable parallel robot. According to the actual operation requirement, the high-frequency vibration suppression system can also be used for suppression of vibration on the under-constrained degree of freedom of the cable parallel robot to realize fast response to vibration on the corresponding degree of freedom; the low-frequency vibration suppression system can also be used for suppression of vibration on the constrained degree of freedom of the cable parallel robot to realize continuous dissipation of vibration energy in the direction.

[0029] For example, for the under-constrained freedom, the low-frequency vibration suppression system 2 is preferentially configured, if the vibration suppression effect of a single low-frequency vibration suppression system is limited, multiple low-frequency vibration suppression systems are configured to jointly perform vibration suppression; for the constrained freedom, the high-frequency vibration suppression system 3 is preferentially configured, and the corresponding high-frequency vibration suppression system is selected according to the specific vibration form, for the mode mainly in translation, the mass block vibration suppression system 31 is preferentially configured; for the mode mainly in rotation, the flywheel vibration suppression system 32 or the pendulum vibration suppression system 33 is preferentially configured; for the mode with both translation and rotation, the mass block vibration suppression system 31 and the flywheel vibration suppression system 32 or the pendulum vibration suppression system 33 are configured, and vibration suppression control is implemented by relying on the cooperation of multiple vibration suppression systems; for the constrained freedom with lower stiffness and larger vibration energy, the low-frequency vibration suppression system 2 and the high-frequency vibration suppression system 3 are configured, so that the continuity and response speed are considered.

[0030] The vibration may occur simultaneously in multiple degrees of freedom during the operation of the cable parallel robot, and for the composite vibration, multiple vibration suppression control systems perform vibration suppression motion simultaneously to cooperatively suppress the vibration.

[0031] Therefore, the application provides a vibration suppression control device and method for a cable parallel robot, which adds an active vibration suppression device to a moving platform of the cable parallel robot, and relies on the vibration suppression device to output a vibration suppression force to the moving platform, so as to dissipate the vibration energy of the moving platform of the cable parallel robot.

[0032] 1. The vibration suppression control device and method for the cable parallel robot can effectively suppress the vibration during the operation of the cable parallel robot, and effectively improve the precision and stability of the cable parallel robot.

[0033] 2. The vibration suppression control method can suppress the vibration on the constrained and under-constrained degrees of freedom of the cable parallel robot, and considers the response speed and continuous vibration suppression effect, is less affected by the rope hysteresis effect compared with the traditional vibration suppression control method relying on adjusting the cable force, and has more significant vibration suppression effect. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 FIG. 1 is a schematic diagram of a cable parallel robot on which a vibration suppression control device according to the application is installed.

[0035] Figure 2 FIG. 5 is a schematic diagram of a low-frequency vibration suppression system according to the application.

[0036] Figure 3 FIG. 8 is a schematic diagram of a mass block vibration suppression system according to the application.

[0037] Figure 4 FIG. 10 is a schematic diagram of a flywheel vibration suppression system according to the application.

[0038] Figure 5 This is a schematic diagram of the pendulum vibration suppression system proposed in this invention. Detailed Implementation

[0039] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. It should be noted that the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0040] This invention provides a vibration damping control device for a cable-parallel robot, such as... Figure 1 As shown. The main structure of the device includes: a low-frequency vibration suppression system 2, a high-frequency vibration suppression system 3, a sensing system 4, and a control system 5. The vibration suppression control device acts on the moving platform 12 of the cable parallel robot 1.

[0041] The low-frequency vibration suppression system 2, high-frequency vibration suppression system 3, and sensing system 4 of the vibration suppression control device are installed on the moving platform 12 of the cable parallel robot. The control system 5 can be installed on the moving platform 12 of the cable parallel robot or integrated into the electrical control cabinet of the cable parallel robot.

[0042] like Figure 2 As shown, the low-frequency vibration suppression system 2 includes a vibration-damping rotor 24, a rotor adjustment rod 23, a directional motor 22, and a base 21. The base 21 is fixed to the moving platform 12 of the cable-connected robot. The housing of the directional motor 22 is mounted on the base 21. The rotor adjustment rod 23 is connected to the motor shaft of the directional motor 22, and the vibration-damping rotor 24 is fixed to the rotor adjustment rod 23. The vibration-damping rotor 24 and the directional motor 22 communicate with the control system 5 via signal cables or wireless signals. The low-frequency vibration suppression system 2 continuously performs work on the moving platform 12 through the high-speed rotation of the vibration-damping rotor 24, thereby dissipating the vibration energy of the moving platform and continuously suppressing low-frequency, large-amplitude vibrations. Simultaneously, the rotation of the directional motor 22 drives the rotor adjustment rod 23 to rotate, thereby adjusting the direction of the vibration-damping rotor 24 and thus the direction of the rotor's vibration-damping force. The advantage of the low-frequency vibration suppression system is its ability to continuously output vibration-damping force to the moving platform; its disadvantage is its relatively low response rate.

[0043] The low frequency vibration suppression system can adjust the direction of the vibration suppression rotor 24 by the steering motor 22, so as to adjust the direction of the rotor vibration suppression force. When the robot has multiple degrees of freedom which need vibration suppression control, if the degrees of freedom are not easy to vibrate at the same time, a set of low frequency vibration suppression systems can be used to realize vibration suppression of multiple degrees of freedom. When vibration occurs in a certain degree of freedom, the steering motor 22 controls the rotor adjusting rod 23 and the vibration suppression rotor 24 to rotate to the corresponding degree of freedom, and performs the vibration suppression task; when vibration does not occur in the degree of freedom and vibration occurs in the remaining degrees of freedom, the steering motor controls the rotor adjusting rod 23 and the vibration suppression rotor 24 to rotate to the degree of freedom where vibration occurs, and performs the corresponding vibration suppression task.

[0044] The high frequency vibration suppression system 3 includes a mass vibration suppression system 31, a flywheel vibration suppression system 32, and a pendulum vibration suppression system 33.

[0045] As shown in Figure 3 , the mass vibration suppression system 31 includes a vibration suppression mass 314, a slide rail 313, a slide rail motor 312, and a mass vibration suppression base 311. The mass vibration suppression base 311 is fixedly connected to the moving platform 12 of the cable parallel robot, the slide rail 313 is installed on the mass vibration suppression base 311, the vibration suppression mass 314 is driven by the slide rail motor 312 and can slide on the slide rail, and the slide rail motor 312 communicates with the control system 5 through a signal cable or wireless signal. The transmission mode of the slide rail motor 312 driving the vibration suppression mass 314 can be a belt wheel, a chain wheel, a screw guide rail, or a linear motor can be used as a slide rail motor to directly drive the vibration suppression mass to move. When vibration suppression control is needed, the slide rail motor 312 drives the vibration suppression mass 314 to move at high speed along the slide rail, thereby generating a large instantaneous reaction force to suppress high frequency and small amplitude instantaneous vibration of the moving platform.

[0046] As shown in Figure 4 , the flywheel vibration suppression system 32 includes a vibration suppression flywheel 323, a flywheel motor 322, and a flywheel vibration suppression base 321. The flywheel vibration suppression base 321 is fixedly connected to the moving platform 12 of the cable parallel robot, the flywheel motor 322 is installed on the flywheel vibration suppression base 321, the vibration suppression flywheel 323 is connected to the motor shaft of the flywheel motor 322, and the flywheel motor 322 communicates with the control system 5 through a signal cable or wireless signal. When vibration suppression control is needed, the flywheel motor 322 drives the vibration suppression flywheel 323 to rotate at high speed, thereby generating a large instantaneous reaction torque to suppress high frequency and small amplitude instantaneous vibration of the moving platform.

[0047] As shown in Figure 5As shown, the pendulum damping system 33 includes a damping pendulum 333, a pendulum motor 332, and a pendulum damping base 331. The pendulum damping base 331 is fixedly connected to the cable parallel robot moving platform 12, the pendulum motor 332 is installed on the base 331, the damping pendulum 333 is connected to the motor shaft of the pendulum motor 332, and the pendulum motor 332 communicates with the control system 5 through a signal cable or wireless signal. When the damping control needs to be implemented, the pendulum motor 332 rotates to drive the damping pendulum 333 to perform accelerated swinging, thereby generating a larger instantaneous reaction force to achieve the suppression of high-frequency and small-amplitude instantaneous vibration of the moving platform.

[0048] The advantage of the high-frequency damping system is fast response speed, and the disadvantage is that it relies on the inertial force generated by acceleration and deceleration to damp, and can only output damping force for a short time. Among them, the mass block damping system 31 is used to suppress the vibration mode mainly in translation, the flywheel damping system 32 is used to suppress the vibration mode mainly in rotation, and the pendulum damping system 33 can suppress the vibration mode mainly in translation and rotation.

[0049] The sensor system 4 is built-in acceleration sensor and gyroscope, installed on the cable parallel robot moving platform 12, communicates with the control system 5 through a signal cable or wireless signal, and is used to measure the acceleration and angular velocity information of the moving platform and transmit it to the control system 5.

[0050] The control system 5 is installed on the cable parallel robot moving platform or integrated into the cable parallel robot control cabinet, used to receive the signals transmitted by the sensor system 4, and control the low-frequency damping system 2 and the high-frequency damping system 3 to perform various damping control movements.

[0051] Based on the proposed cable parallel robot damping control device, a cable parallel robot damping control method is proposed to suppress the vibration of the cable parallel robot moving platform. The main process of the damping control method is as follows:

[0052] Step one: Through elastic dynamics modeling and modal analysis of the cable parallel robot, the typical vibration form and natural frequency of the cable parallel robot are determined. Alternatively, through excitation experiment, the typical vibration form and natural frequency of the cable parallel robot are determined. According to the characteristics of each mode, the corresponding threshold value is set. When the vibration speed and angular velocity of the cable parallel robot are greater than the threshold value, the damping control device will be started to implement damping control, otherwise the damping control device will not be started.

[0053] Step two: According to the analysis results of the natural frequency, the damping control device is arranged at the corresponding position of the moving platform of the cable parallel robot. For the modes on the under-constrained degrees of freedom of the cable parallel robot, the low-frequency damping system 2 is preferentially installed in the vibration direction; for the modes on the constrained degrees of freedom of the cable parallel robot, the high-frequency damping system 3 is preferentially installed in the vibration direction.

[0054] Step three: the acceleration and angular velocity of the moving platform 12 of the cable parallel robot are continuously detected by the sensing system 4, and compared with the theoretical acceleration and angular velocity of the cable parallel robot. After low-pass filtering, it is identified whether the moving platform 2 has vibration. If the moving platform 12 has vibration, the acceleration and angular velocity direction and size corresponding to the vibration amount are solved. In addition, the acceleration signal is integrated and high-pass filtered in the control system 5 to obtain the moving platform speed signal.

[0055] Step four: judge the vibration type of the moving platform. If the acceleration and angular velocity of the moving platform appear on the under-constrained degree of freedom, the corresponding low-frequency vibration suppression system 2 is adjusted to implement vibration suppression; if the acceleration and angular velocity of the moving platform appear on the constrained degree of freedom, the corresponding high-frequency vibration suppression system 3 is adjusted to implement vibration suppression.

[0056] For the vibration that needs to adjust the low-frequency vibration suppression system 2 to implement vibration suppression, the key of the vibration suppression control of such vibration is to continuously dissipate vibration energy. For such vibration, according to the direction of the vibration speed signal, the direction motor 22 is controlled to rotate, so that the direction of the force of the vibration suppression rotor 24 is opposite to the direction of the vibration speed, and then the vibration suppression rotor 24 rotates at high speed and continuously outputs the vibration suppression force to the moving platform, so as to realize the continuous dissipation of vibration energy.

[0057] For the vibration that needs to adjust the high-frequency vibration suppression system 3 to implement vibration suppression, the key of the vibration suppression control of such vibration is to quickly offset the vibration acceleration and generate the vibration suppression force, and reduce the amplitude. For such vibration, according to the direction of the vibration acceleration signal, the motor driving the vibration suppression mass block 314, the vibration suppression flywheel 323 or the vibration suppression pendulum 333 in the corresponding direction is controlled to execute acceleration and deceleration motion, so that the high-frequency vibration suppression system 3 generates inertia force or inertia torque in the direction opposite to the acceleration signal, and realizes the suppression of vibration.

[0058] Step five: during the vibration suppression process, the acceleration and angular velocity of the moving platform of the cable parallel robot are continuously detected, and the velocity signal is obtained by integrating the acceleration. It is continuously judged whether the vibration speed and angular velocity of the cable parallel robot are greater than the threshold value. When the speed and angular velocity of the cable parallel robot on the corresponding mode are less than the threshold value, the vibration suppression control system stops working.

[0059] The following will be described in combination with Figure 1A case of installing and using the vibration suppression control device for cable parallel robot on a typical cable parallel robot is introduced. In this embodiment, the moving platform 12 of the cable parallel robot 1 is driven by six ropes 11. The translational degree of freedom of the cable parallel robot along the Y-axis direction is under-constrained, and the vibration is mainly free swing of the cable parallel robot, with a low frequency, generally 0.01-1 Hz. The translational degrees of freedom along the X-axis and Z-axis directions and the rotational degrees of freedom around the X, Y and Z axes are constrained, and the vibration is mainly caused by elastic deformation of the ropes, with a high frequency, generally 1-30 Hz.

[0060] According to the modal analysis results of the cable parallel robot, the natural frequency of the cable parallel robot along the translational degree of freedom along the Z-axis direction and the rotational degree of freedom around the Z axis is high, and the vibration is not easy to occur. Therefore, the vibration suppression control device is configured on the remaining four degrees of freedom. The low-frequency vibration suppression system 2 is installed on the translational degree of freedom along the Y-axis direction, the mass block vibration suppression system 31 is installed on the translational degree of freedom along the X-axis direction, the flywheel vibration suppression system 32 is installed on the rotational degree of freedom around the Y-axis, and two sets of pendulum vibration suppression systems 33 are installed on the rotational degree of freedom around the X-axis.

[0061] When the moving platform 12 of the cable parallel robot vibrates along the Y-axis translational direction and the vibration velocity component is greater than the preset threshold, the low-frequency vibration suppression system 2 starts to work, the adjusting motor 22 rotates the vibration suppression rotor 24 to the vibration direction, the vibration suppression rotor starts to rotate, continuously outputs a force opposite to the vibration velocity to the moving platform 12, and suppresses the vibration. In addition, for this vibration, the pendulum vibration suppression system 33 can also participate in the vibration suppression control to implement auxiliary vibration suppression. The vibration suppression pendulum 333 is accelerated to swing in the direction opposite to the vibration velocity by the pendulum motor 332, an inertial reaction force is generated, and the auxiliary suppression of the vibration is realized.

[0062] When the moving platform 12 of the cable parallel robot vibrates along the X-axis translational direction and the vibration velocity component is greater than the preset threshold, the mass block vibration suppression system 31 starts to work, the vibration suppression mass block 314 is accelerated to move in the direction opposite to the vibration velocity by the slide rail motor 312, an inertial reaction force is generated, and the vibration is suppressed. In addition, for this vibration, the low-frequency vibration suppression system 2 can also participate in the vibration suppression control to implement auxiliary vibration suppression. The vibration suppression rotor 24 is rotated to the vibration direction by the adjusting motor 22, the wind force generated by the rotation of the vibration suppression rotor is used to continuously output a force opposite to the vibration velocity to the moving platform 12, and the vibration is suppressed.

[0063] When the moving platform 12 of the cable parallel robot vibrates along the X-axis translational direction and the vibration velocity component is greater than the preset threshold, the mass block vibration suppression system 31 starts to work, the vibration suppression mass block 314 is accelerated to move in the direction opposite to the vibration velocity by the slide rail motor 312, an inertial reaction force is generated, and the vibration is suppressed. In addition, for this vibration, the low-frequency vibration suppression system 2 can also participate in the vibration suppression control to implement auxiliary vibration suppression. The vibration suppression rotor 24 is rotated to the vibration direction by the adjusting motor 22, the wind force generated by the rotation of the vibration suppression rotor is used to continuously output a force opposite to the vibration velocity to the moving platform 12, and the vibration is suppressed.

[0064] When the vibration of the moving platform 12 of the cable parallel robot occurs around the X-axis rotation freedom, and the angular velocity component is greater than the preset threshold, the pendulum vibration suppression system 33 starts to work, and the vibration suppression pendulum 333 is driven to rotate around the angular velocity reverse direction by the pendulum motor 332, so as to generate the inertial reaction torque, and realize the suppression of the vibration.

[0065] It is worth noting that, although the technical solutions and preferred embodiments of the present application are described in detail above in combination with the drawings, the present application is not limited to the specific embodiments described above, and the above-described embodiments are only illustrative. Those skilled in the art can make many forms based on the inspiration of the present application without departing from the purpose of the present application and the protection scope of the claims.

Claims

1. A vibration damping control device for a cable-connected robot, characterized in that, The application relates to a vibration suppression system for a cable parallel robot. The vibration suppression system comprises a low-frequency vibration suppression system (2), a high-frequency vibration suppression system (3), a sensing system (4) and a control system (5), wherein the low-frequency vibration suppression system (2), the high-frequency vibration suppression system (3) and the sensing system (4) are installed on a moving platform (12) of the cable parallel robot, and the control system (5) is installed on the moving platform (12) of the cable parallel robot or integrated into a control cabinet of the cable parallel robot, and the control system (5) communicates with the low-frequency vibration suppression system (2), the high-frequency vibration suppression system (3) and the sensing system (4) through a cable or wireless signals. The low-frequency vibration suppression system (2) comprises a vibration suppression rotor (24), a rotor adjusting rod (23), a direction adjusting motor (22) and a base (21), wherein the base (21) is fixedly connected to the moving platform (12) of the cable parallel robot, the direction adjusting motor (22) is installed on the base (21), the rotor adjusting rod (23) is connected to a motor shaft of the direction adjusting motor (22), and the vibration suppression rotor (24) is fixedly connected to the rotor adjusting rod (23); the vibration suppression rotor (24) and the direction adjusting motor (22) communicate with the control system (5) through signal cables or wireless signals; the low-frequency vibration suppression system (2) continuously works on the moving platform (12) through high-speed rotation of the vibration suppression rotor (24), so that vibration energy of the moving platform (12) is dissipated, and low-frequency and large-amplitude vibration of the moving platform (12) is continuously suppressed; meanwhile, the direction adjusting motor (22) is rotated to drive the rotor adjusting rod (23) to rotate, so that the direction of the vibration suppression rotor (24) is adjusted, and then the direction of the vibration suppression force of the vibration suppression rotor is adjusted. The high-frequency vibration suppression system (3) comprises a mass vibration suppression system (31), a flywheel vibration suppression system (32) and a pendulum vibration suppression system (33). The mass vibration suppression system (31) comprises a vibration suppression mass (314), a slide rail (313), a slide rail motor (312) and a mass vibration suppression base (311), wherein the mass vibration suppression base (311) is fixedly connected to the moving platform (12) of the cable parallel robot, the slide rail (313) is installed on the mass vibration suppression base (311), the vibration suppression mass (314) is driven by the slide rail motor (312) and can slide on the slide rail, and the slide rail motor (312) communicates with the control system (5) through signal cables or wireless signals; when the vibration suppression control is needed to be implemented, the slide rail motor (312) drives the vibration suppression mass (314) to move along the slide rail (313) at a high speed, so that a large instantaneous reaction force is generated, and high-frequency and small-amplitude instantaneous vibration of the moving platform (12) is suppressed. ​ The flywheel vibration suppression system (32) comprises a flywheel (323), a flywheel motor (322) and a flywheel vibration suppression base (321); the flywheel vibration suppression base (321) is fixedly connected to the moving platform (12) of the cable parallel robot, the flywheel motor (322) is installed on the flywheel vibration suppression base (321), the flywheel (323) is connected to the motor shaft of the flywheel motor (322), and the flywheel motor (322) communicates with the control system (5) through a signal cable or wireless signal; when vibration suppression control is needed, the flywheel motor (322) rotates to drive the flywheel (323) to rotate at a high speed, thereby generating a large instantaneous reaction torque, and the high-frequency and small-amplitude instantaneous vibration of the moving platform is suppressed; The pendulum vibration suppression system (33) comprises a pendulum (333), a pendulum motor (332) and a pendulum vibration suppression base (331); the pendulum vibration suppression base (331) is fixedly connected to the moving platform (12) of the cable parallel robot, the pendulum motor (332) is installed on the pendulum vibration suppression base (331), the pendulum (333) is connected to the motor shaft of the pendulum motor (332), and the pendulum motor (332) communicates with the control system (5) through a signal cable or wireless signal; when vibration suppression control is needed, the pendulum motor (332) rotates to drive the pendulum (333) to execute accelerated swing, thereby generating a large instantaneous reaction force, and the high-frequency and small-amplitude instantaneous vibration of the moving platform is suppressed; The mass block vibration suppression system (31) is used to suppress the translational vibration mode, the flywheel vibration suppression system (32) is used to suppress the rotational vibration mode, and the pendulum vibration suppression system (33) can suppress both the translational vibration mode and the rotational vibration mode; The sensing system (4) comprises an acceleration sensor and a gyroscope, communicates with the control system (5) through a signal cable or wireless signal, and is used to measure the acceleration and angular velocity information of the moving platform (12) and transmit the information to the control system (5); The control system (5) is used to receive the signals transmitted by the sensing system (4) and control the low-frequency vibration suppression system (2) and the high-frequency vibration suppression system (3) to execute vibration suppression control movements.

2. The cable parallel robot vibration suppression control device according to claim 1, characterized by, For different cable parallel robots, the vibration modes to be suppressed are selected according to the typical modal characteristics and working environment characteristics of the cable parallel robot, and different types, numbers and layouts of the low-frequency vibration suppression system (2) and / or the high-frequency vibration suppression system (3) are selected and matched; multiple low-frequency vibration suppression systems (2) and / or high-frequency vibration suppression systems (3) of the same type or different types are selected and matched on the same degree of freedom, and more comprehensive vibration suppression control effects are achieved through the cooperation of the multiple low-frequency vibration suppression systems (2) and / or high-frequency vibration suppression systems (3). Specifically: for the under-constrained degree of freedom, the low-frequency vibration suppression system (2) is preferentially configured, and if the single low-frequency vibration suppression system has limited vibration suppression effect, multiple low-frequency vibration suppression systems are configured to jointly perform vibration suppression; for the constrained degree of freedom, the high-frequency vibration suppression system (3) is preferentially configured, and the corresponding high-frequency vibration suppression system is selected according to the specific vibration form; for the mode mainly in translation, the mass block vibration suppression system (31) is preferentially configured; for the mode mainly in rotation, the flywheel vibration suppression system (32) or the pendulum vibration suppression system (33) is preferentially configured; for the mode with both translation and rotation, the mass block vibration suppression system (31) and the flywheel vibration suppression system (32) or the pendulum vibration suppression system (33) are configured to implement vibration suppression control through the cooperation of multiple vibration suppression systems; for the constrained degree of freedom with low stiffness and large vibration energy, both the low-frequency vibration suppression system (2) and the high-frequency vibration suppression system (3) are configured, so as to achieve the consideration of persistence and response speed.

3. The cable parallel robot vibration suppression control device according to claim 1, characterized by, The low-frequency vibration suppression system (2) adjusts the direction of the vibration suppression rotor (24) by using the direction adjusting motor (22), so as to adjust the direction of the rotor vibration suppression force; when the moving platform (12) has multiple degrees of freedom that need vibration suppression control, if the degrees of freedom are not easy to vibrate at the same time, a group of low-frequency vibration suppression systems (2) are used to realize the vibration suppression of multiple degrees of freedom; when vibration occurs on a certain degree of freedom, the direction adjusting motor (22) controls the vibration suppression rotor (24) to point to the corresponding degree of freedom to perform the vibration suppression task; when vibration does not occur on the degree of freedom and vibration occurs on the remaining degrees of freedom, the direction adjusting motor (22) controls the vibration suppression rotor (24) to point to the degree of freedom where vibration occurs to perform the corresponding vibration suppression task.

4. The cable parallel robot vibration suppression control device according to claim 1, characterized by, The transmission mode of the slide rail motor (312) driving the vibration suppression mass block (314) is a belt wheel, a chain wheel or a lead screw guide rail.

5. The cable parallel robot vibration suppression control device according to claim 1, characterized by, A linear motor is used as the slide rail motor to directly drive the vibration suppression mass block to move.

6. A vibration suppression control method for a cable parallel robot, characterized by, The method uses the vibration suppression control device of any one of claims 1 to 5 to realize the suppression of the vibration of the moving platform of the cable parallel robot; The typical vibration of the cable parallel robot includes two types. One type is the free vibration on the under-constrained degree of freedom, and the vibration characteristics of this type are low frequency, large amplitude and difficult to dissipate vibration energy. The other type is the elastic vibration on the constrained degree of freedom, and the vibration characteristics of this type are high frequency, small amplitude and vibration energy is continuously dissipated due to the elasticity and damping of the cable. Therefore, the vibration suppression control method is as follows: Step one: through elastic dynamics modeling and modal analysis of the cable parallel robot (1), the typical vibration form and natural frequency of the cable parallel robot (1) are determined; or through excitation experiment, the typical vibration form and natural frequency of the cable parallel robot (1) are determined; according to the characteristics of each mode, the corresponding threshold value is set, when the vibration speed and angular velocity of the cable parallel robot are greater than the threshold value, the vibration suppression control device is started to implement vibration suppression, otherwise the vibration suppression control device is not started. Step two: According to the inherent frequency analysis results, the vibration suppression control device is arranged on the corresponding degree of freedom of the moving platform of the cable parallel robot; for the mode on the under-constrained degree of freedom of the cable parallel robot, the low-frequency vibration suppression system (2) is preferentially installed in the vibration direction; for the mode on the constrained degree of freedom of the cable parallel robot, the high-frequency vibration suppression system (3) is preferentially installed in the vibration direction; Step three: The acceleration and angular velocity of the moving platform (12) of the cable parallel robot are continuously detected by the sensing system (4), and compared with the theoretical acceleration and angular velocity of the cable parallel robot. After low-pass filtering, it is identified whether the moving platform (12) has vibration; if the moving platform (12) has vibration, the acceleration and angular velocity corresponding to the vibration amount are solved; in addition, the acceleration signal is integrated and high-pass filtered in the control system (5) to obtain the moving platform speed signal; Step four: The vibration type of the moving platform (12) is judged. If the acceleration and angular velocity of the moving platform appear on the under-constrained degree of freedom, the corresponding low-frequency vibration suppression system (2) is activated to suppress vibration; if the acceleration and angular velocity of the moving platform appear on the constrained degree of freedom, the corresponding high-frequency vibration suppression system (3) is activated to suppress vibration; for the vibration that needs to activate the low-frequency vibration suppression system (2) to suppress vibration, the focus of the vibration suppression control of such vibration is to continuously dissipate vibration energy; for such vibration, according to the vibration speed signal direction, the direction motor (22) is controlled to rotate, so that the direction of the force of the vibration suppression rotor (24) is opposite to the direction of the vibration speed, and then the vibration suppression rotor (24) rotates at high speed to continuously output the vibration suppression force to the moving platform (12), realizing the continuous dissipation of vibration energy; For the vibration that needs to activate the high-frequency vibration suppression system (3) to suppress vibration, the focus of the vibration suppression control of such vibration is to quickly offset the generated vibration suppression force and vibration acceleration, and reduce the amplitude; for such vibration, according to the direction of the vibration acceleration signal, the motor driving the vibration suppression mass block (314), the vibration suppression flywheel (323) or the vibration suppression pendulum (333) in the corresponding direction is controlled to execute acceleration and deceleration motion, so that the high-frequency vibration suppression system (3) generates an inertial force or an inertial torque in the direction opposite to the acceleration signal, realizing the suppression of vibration; Step five: During the vibration suppression process, the acceleration and angular velocity of the moving platform (12) of the cable parallel robot are continuously detected by the sensing system (4), and the speed signal is obtained by integrating the acceleration; it is continuously judged whether the vibration speed and angular velocity of the cable parallel robot are greater than the threshold value, and when the speed and angular velocity of the corresponding mode of the cable parallel robot are less than the threshold value, the corresponding vibration suppression control system stops working.

7. The cable parallel robot vibration suppression control method according to claim 6, characterized by, According to the actual operation requirements, the high-frequency vibration suppression system (3) can also be used for the suppression of vibration on the under-constrained degree of freedom of the cable parallel robot, and the low-frequency vibration suppression system (2) can also be used for the suppression of vibration on the constrained degree of freedom of the cable parallel robot.

8. The cable parallel robot vibration suppression control method according to claim 6, characterized by, During the operation of the cable parallel robot, vibration may occur simultaneously on multiple degrees of freedom. For such composite vibration, multiple vibration suppression control systems simultaneously execute vibration suppression motion to cooperatively suppress vibration.

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