A method, device, electronic device and storage medium for suppressing grinding vibration

Abstract

The present disclosure provides a method, apparatus, electronic device, and storage medium for suppressing grinding vibration. Among them, the method includes: obtaining original vibration data during the grinding process of a workpiece; inputting the original vibration data into a vibration position compensation prediction model to determine a vibration position compensation prediction value; obtaining the contact force during the grinding process of the workpiece; inputting the contact force into a force control position compensation model to determine a force control position compensation prediction value; determining a displacement compensation amount according to the vibration position compensation prediction value and the force control position compensation prediction value; and inputting the displacement compensation amount into a position controller to perform position control on the end effector.

Description

Technical Field

[0001] The present disclosure relates to the field of automated grinding, and particularly to a method, device, electronic device, and storage medium for suppressing grinding vibration. Background Art

[0002] Large thin-walled metal parts such as wind turbine blades, engine blades, and aircraft skins, as well as new carbon fiber composite structural parts, are widely used in industries such as aerospace, rail transit, and energy production. The final surface machining of these parts or structural parts must meet the industrial requirements for surface quality and dimensional accuracy, and usually grinding machining is adopted. However, at present, the automatic grinding methods for large thin-walled parts or carbon fiber structural parts are limited in both quantity and use, and a large number of workpieces are still machined manually. The underdevelopment of automatic grinding for large thin-walled parts or carbon fiber structural parts is largely due to their inherent low stiffness characteristics, which often cause grinding chatter and forced vibration of the workpieces to be ground, having a catastrophic impact on the surface quality. Even worse, it will result in unstable grinding forces, and in some cases, may cause separation between the tool and the workpiece.

[0003] In the prior art, numerical control machining personnel solve the vibration control problem by optimizing process parameters to reduce the intensity of the vibration source, by designing vibration dampers, auxiliary fixtures, and additional dampers to change the vibration transmission path, and by using piezoelectric actuators and control algorithms to manipulate the structural response. Robot machining personnel often focus on the vibration control of robots and tools. However, when grinding large thin-walled parts or carbon fiber components, low-stiffness workpieces are the key factors for grinding stability, and vibration control must be considered. But until recently, vibration suppression methods for robot grinding of low-stiffness workpieces have been rare. Therefore, the problem involved is further defined as how to suppress workpiece vibration through effective force-position control and improve grinding efficiency and quality in the robot grinding of weakly rigid parts. Summary of the Invention

[0004] The present disclosure provides a method, device, electronic device, and storage medium for suppressing grinding vibration to at least solve the above technical problems existing in the prior art.

[0005] According to a first aspect of the present disclosure, a method for suppressing grinding vibration is provided, the method comprising:

[0006] Obtaining original vibration data during the grinding of a workpiece;

[0007] Inputting the original vibration data into a vibration position compensation prediction model to determine a vibration position compensation prediction value;

[0008] Obtaining the contact force during the grinding of the workpiece;

[0009] Input the contact force into the force control position compensation model to determine the predicted value of the force control position compensation;

[0010] Determine the displacement compensation amount according to the predicted value of the vibration position compensation and the predicted value of the force control position compensation;

[0011] Input the displacement compensation amount into the position controller to perform position control on the end effector.

[0012] In an implementable manner, the inputting the original vibration data into the vibration position compensation prediction model to determine the predicted value of the vibration position compensation includes:

[0013] Step S1: Determine the first vibration mode function of the original vibration data according to empirical mode decomposition;

[0014] Step S2: Eliminate the first vibration mode function from the original vibration data to determine the first function;

[0015] Step S3: Judge whether the mean curve of the upper envelope line and the lower envelope line of the first function is a monotonic function;

[0016] If it is a monotonic function, substitute the first vibration mode function into the vibration position compensation prediction model to determine the predicted value of the vibration position compensation;

[0017] If it is not a monotonic function, use the first function as the new original vibration data, and repeat steps S1 to S3 until the p-th vibration mode function and the p-th function are obtained, and the mean curve of the upper envelope line and the lower envelope line of the p-th function is a monotonic function;

[0018] Step S4: Select the three vibration mode functions with the highest frequencies from the first vibration mode function to the p-th vibration mode function;

[0019] Step S5: Substitute the three vibration mode functions with the highest frequencies into the vibration position compensation prediction model to determine the predicted value of the vibration position compensation.

[0020] In an implementable manner, the determining the first vibration mode function of the original vibration data according to empirical mode decomposition includes:

[0021] Step S1-1: Determine the upper envelope line composed of all the maximum value points of the original vibration data and the lower envelope line composed of all the minimum value points of the original vibration data according to the original vibration data;

[0022] Step S1-2: Determine the original vibration mode function of the original vibration data according to the upper envelope line and the lower envelope line;

[0023] Step S1-3: Determine whether the original vibration mode function satisfies the following two conditions:

[0024] Condition 1: The mean values of the upper envelope line and the lower envelope line at any moment are both zero;

[0025] Condition 2: The number of points exceeding zero is equal to or differs by one from the number of extreme points;

[0026] If the original vibration mode function simultaneously satisfies the above Condition 1 and Condition 2, then record the original vibration mode function as the first vibration mode function;

[0027] If the original vibration mode function does not simultaneously satisfy Condition 1 and Condition 2, then use the original vibration mode function as new original vibration data, and re-execute Step S1-1 to Step S1-3 until the finally obtained vibration mode function satisfies Condition 1 and Condition 2.

[0028] Step S1-4: Record the finally obtained vibration mode function that satisfies Condition 1 and Condition 2 as the first vibration mode function.

[0029] In an implementable manner, the substituting the three vibration mode functions with the highest frequencies into the vibration position compensation prediction model to determine the vibration position compensation prediction value includes:

[0030] Perform Fourier transform on the three vibration mode functions with the highest frequencies;

[0031] Respectively obtain the maximum amplitudes of the three vibration mode functions after Fourier transform;

[0032] Substitute the maximum amplitudes into the vibration position compensation prediction model to determine the vibration position compensation prediction value.

[0033] In an implementable manner, the vibration position compensation prediction model is shown by the following formula:

[0034]

[0035] Wherein, is the vibration position compensation prediction value, , , are proportionality coefficients, and 1, , , are respectively the maximum amplitudes of the three vibration mode functions.

[0036] In an implementable manner, the inputting the contact force into the force control position compensation model to determine the force control position compensation prediction value includes:

[0037] Determine the dynamic equation of the end effector according to the dynamic model of the end effector;

[0038] Perform Laplace transform on the dynamic equation to obtain a force control position compensation prediction model;

[0039] Determine the force control position compensation prediction value according to the force control position compensation prediction model.

[0040] In an implementable manner, the determining the displacement compensation amount according to the vibration position compensation prediction value and the force control position compensation prediction value includes:

[0041] Determine the displacement compensation amount according to the following formula:

[0042]

[0043] Wherein, is the displacement compensation amount, is the vibration position compensation prediction value, is the force control position compensation prediction value.

[0044] According to a second aspect of the present disclosure, there is provided a grinding vibration suppression device, the device includes:

[0045] A first acquisition unit configured to acquire original vibration data during the grinding of the workpiece;

[0046] A first determination unit configured to input the original vibration data into a vibration position compensation prediction model to determine a vibration position compensation prediction value;

[0047] A second acquisition unit configured to acquire the contact force during the grinding of the workpiece;

[0048] A second determination unit configured to input the contact force into a force control position compensation model to determine a force control position compensation prediction value;

[0049] A third determination unit configured to determine a displacement compensation amount according to the vibration position compensation prediction value and the force control position compensation prediction value;

[0050] A control unit configured to input the displacement compensation amount into a position controller to perform position control on the end effector.

[0051] According to a third aspect of the present disclosure, there is provided an electronic device, including:

[0052] At least one processor; and

[0053] A memory communicatively connected to the at least one processor; wherein,

[0054] The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the method described in the present disclosure.

[0055] According to a fourth aspect of the present disclosure, there is provided a non-transitory computer-readable storage medium storing computer instructions for causing a computer to execute the method described in the present disclosure.

[0056] In the vibration suppression method, device, electronic device and storage medium of the present disclosure, by converting complex robot control into simple end effector control, a force control position compensation prediction value is obtained by establishing a mathematical model for the grinding process of the end effector. At the same time, a vibration position compensation prediction value obtained by analyzing the vibration data of the workpiece is combined to improve the force control effect, avoid an increase in the vibration amplitude caused by an excessive force control error during force control, and further improve the vibration suppression effect of the workpiece.

[0057] In the present disclosure, for the problem of vibration suppression of weakly rigid workpieces during the grinding process, the position of the grinding head is adjusted in real time according to the vibration mode and the contact force. The vibration suppression effect is obvious, the force control accuracy is improved, and the consistency of the machining quality and the machining efficiency can be well guaranteed.

[0058] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present disclosure, nor is it used to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] By reading the following detailed description with reference to the accompanying drawings, the above and other objects, features and advantages of the exemplary embodiments of the present disclosure will become readily understood. In the drawings, several embodiments of the present disclosure are shown by way of example and not limitation, wherein:

[0060] In the drawings, the same or corresponding reference numerals represent the same or corresponding parts.

[0061] Figure 1 is a flowchart of the vibration suppression method for grinding provided by an embodiment of the present disclosure;

[0062] Figure 2 is a detailed processing procedure diagram of the vibration suppression method for grinding provided by an embodiment of the present disclosure;

[0063] Figure 3 is a schematic diagram of the original vibration data and its corresponding vibration mode function curve provided by an embodiment of the present disclosure;

[0064] Figure 4 is a comparison diagram of the vibration amplitudes of workpieces during the grinding process using the conventional grinding method and the method of the embodiment of the present disclosure;

[0065] Figure 5 The surface quality diagram after polishing a workpiece with weak rigidity by a conventional method;

[0066] Figure 6 The surface quality diagram after polishing a workpiece with weak rigidity by the method of the embodiment of the present disclosure;

[0067] Figure 7 The schematic diagram of the polishing vibration suppression device provided by the embodiment of the present disclosure;

[0068] Figure 8 The schematic diagram of the composition structure of an electronic device according to an embodiment of the present disclosure is shown. Specific embodiments

[0069] To make the objectives, features, and advantages of the present disclosure more obvious and understandable, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments are only a part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present disclosure.

[0070] The force / position hybrid control method of an industrial robotic arm mainly obtains the change in the robot's torque through the contact force, and further controls the robot's displacement to reach the specified position to achieve force control. For workpieces with strong rigidity, better polishing effects can be obtained. However, when polishing workpieces with weak rigidity, violent vibrations are likely to occur during the polishing process. It is difficult to ensure the polishing quality of the robot without considering the workpiece vibrations. At the same time, different levels of robot open source will make it difficult to obtain and control the internal joint torque information of the robot.

[0071] Based on this, the embodiment of the present disclosure provides a polishing vibration suppression method. Figure 1 The flowchart of the polishing vibration suppression method provided by the embodiment of the present disclosure. Figure 2 The detailed processing procedure diagram of the polishing vibration suppression method provided by the embodiment of the present disclosure, as Figure 1 and Figure 2 shown, the method includes the following steps:

[0072] Step 101, obtaining the original vibration data during the workpiece polishing process.

[0073] Specifically, the original vibration data during the polishing process within t time can be collected by a vibration sensor, and the original vibration data can be denoted as X(t).

[0074] Step 102: Input the original vibration data into the vibration position compensation prediction model to determine the vibration position compensation prediction value.

[0075] In one embodiment, inputting the original vibration data into a vibration position compensation prediction model to determine a vibration position compensation prediction value includes:

[0076] Step S1: Determine the first vibration mode function of the original vibration data according to empirical mode decomposition;

[0077] Step S2: Eliminate the first vibration mode function from the original vibration data to determine the first function;

[0078] Step S3: Determine whether the mean curve of the upper envelope line and the lower envelope line of the first function is a monotonic function;

[0079] If it is a monotonic function, substitute the first vibration mode function into the vibration position compensation prediction model to determine the vibration position compensation prediction value;

[0080] If it is not a monotonic function, use the first function as the new original vibration data, and repeat steps S1 to S3 until the p-th vibration mode function and the p-th function are obtained, and the mean curve of the upper envelope line and the lower envelope line of the p-th function is a monotonic function;

[0081] Step S4: Select the three vibration mode functions with the highest frequencies among the first vibration mode function to the p-th vibration mode function;

[0082] Step S5: Substitute the three vibration mode functions with the highest frequencies into the vibration position compensation prediction model to determine the vibration position compensation prediction value.

[0083] In one embodiment, determining the first vibration mode function of the original vibration data according to empirical mode decomposition includes:

[0084] Step S1-1: Determine the upper envelope line composed of all the maximum points of the original vibration data and the lower envelope line composed of all the minimum points of the original vibration data according to the original vibration data;

[0085] Step S1-2: Determine the original vibration mode function of the original vibration data according to the upper envelope line and the lower envelope line;

[0086] Step S1-3: Determine whether the original vibration mode function satisfies the following two conditions:

[0087] Condition 1: The mean value of the upper envelope line and the lower envelope line at any time is zero;

[0088] Condition 2: The number of points exceeding zero is equal to or differs by one from the number of extreme points;

[0089] If the original vibration mode function simultaneously satisfies the above Condition 1 and Condition 2, record the original vibration mode function as the first vibration mode function;

[0090] If the original vibration mode function does not satisfy both Condition 1 and Condition 2 simultaneously, then use the original vibration mode function as the new original vibration data, and re-execute steps S1-1 to S1-3 until the finally obtained vibration mode function satisfies Condition 1 and Condition 2.

[0091] Step S1-4: Denote the finally obtained vibration mode function that satisfies Condition 1 and Condition 2 as the first vibration mode function.

[0092] Specifically, first execute step S1-1, and truncate the collected original vibration data using a window function to obtain the mean curve of the upper and lower envelope lines :

[0093]

[0094] where is the upper envelope line formed by connecting all the maximum points of with a curve, and is the lower envelope line formed by connecting all the minimum points of with a curve.

[0095] Next, execute step S1-2, and perform sifting on the original vibration data through empirical mode decomposition to obtain the original vibration mode function :

[0096]

[0097] Next, execute step S1-3, and judge whether simultaneously satisfies Condition 1 and Condition 2;

[0098] Condition 1: The mean values of the upper and lower envelope lines at any time are both zero;

[0099] Condition 2: The number of times exceeding zero is equal to or differs by one from the number of extreme points;

[0100] If simultaneously satisfies Condition 1 and Condition 2, then use as the first vibration mode function of , and denote ;

[0101] If does not satisfy Condition 1 and Condition 2 simultaneously, then use the original vibration mode function as the new original vibration data, and re-execute steps S1-1 to S1-3 to obtain The mean curve of the upper and lower envelope lines , find :

[0102]

[0103] Judge Whether conditions 1 and 2 are satisfied simultaneously. If not, then use As the new original vibration data, continue to repeat the methods of steps S1-1 to S1-3 until the obtained Satisfies both condition 1 and condition 2 simultaneously.

[0104] Next, execute step S1-4, and denote the vibration mode function that finally satisfies conditions 1 and 2 As the first vibration mode function , that is, denote As The first vibration mode function of, where Is obtained after Repeating the methods of steps S1-1 to S1-3 for times.

[0105] Next, execute step S2, and eliminate the first vibration mode function Of from To obtain the first function , denote .

[0106] Next, execute step S3. If The mean curve of the upper and lower envelope curves of is a monotonic function, then end the screening; if The mean curve of the upper and lower envelope curves of is not a monotonic function, then use As the new original vibration data, continue to execute according to steps S1 to S3 to obtain The second vibration mode function And the second function . If the mean curve of the second function Of the upper and lower envelope curves is a monotonic function, then end the screening. If The mean curve of the upper and lower envelope curves of is not a monotonic function, then repeat steps S1 to S3. Repeat this execution to obtain Simultaneously satisfying conditions 1 and 2 Of the vibration mode functions, that is, complete the modal analysis of the original vibration data , denoted as:

[0107]

[0108] Among them, The mean curve of the upper and lower envelope curves is a monotonic function.

[0109] Next, step S4 is executed to obtain number of vibration mode functions are sorted in descending order of frequency, and the first three of them are denoted as 、 、 .

[0110] Next, step S5 is executed, and the three vibration mode functions with the highest frequencies are substituted into the vibration position compensation prediction model to determine the vibration position compensation prediction value.

[0111] In one embodiment, substituting the three vibration mode functions with the highest frequencies into the vibration position compensation prediction model to determine the vibration position compensation prediction value includes:

[0112] Performing Fourier transform on the three vibration mode functions with the highest frequencies;

[0113] Respectively obtaining the maximum amplitudes of the three vibration mode functions after Fourier transform;

[0114] Substituting the maximum amplitudes into the vibration position compensation prediction model to determine the vibration position compensation prediction value.

[0115] Specifically, respectively perform Fourier transform on 、 、 to obtain 、 、 , denote the maximum amplitude in as , the maximum amplitude in as , the maximum amplitude in as , establish a vibration position compensation prediction model:

[0116]

[0117] where, is the vibration position compensation prediction value, 、 、 are proportionality coefficients, and 1. If the number of vibration mode functions obtained , then set according to 1, ; if the number of vibration mode functions obtained , then set according to 、 ​​​​​​, Settings.

[0118] Figure 3 This is a schematic diagram of the original vibration data and its corresponding vibration mode function curves in the embodiments of the present disclosure. In this embodiment, the original vibration data during the grinding process is collected within 800 ms by a vibration sensor. Among them, figure (a) shows the original vibration data, figure (b) shows the corresponding first vibration mode function curve, figure (c) shows the corresponding second vibration mode function curve, figure (d) shows the corresponding third vibration mode function curve, figure (e) shows the corresponding fourth vibration mode function curve, figure (f) shows the corresponding fifth vibration mode function curve, figure (g) shows the corresponding sixth vibration mode function curve, and figure (h) shows the corresponding seventh vibration mode function curve.

[0119] Step 103: Obtain the contact force during the workpiece grinding process.

[0120] Specifically, the contact force during the workpiece grinding process can be obtained through a torque sensor.

[0121] Step 104: Input the contact force into the force control position compensation model to determine the predicted value of the force control position compensation.

[0122] In one embodiment, inputting the contact force into the force control position compensation model to determine the predicted value of the force control position compensation includes:

[0123] Determine the dynamic equation of the end effector according to the dynamic model of the end effector;

[0124] Perform Laplace transform on the dynamic equation to obtain the force control position compensation prediction model;

[0125] Determine the predicted value of the force control position compensation according to the force control position compensation prediction model.

[0126] Specifically, based on the dynamic model of the end effector during the grinding process, the dynamic equation of the end effector is obtained:

[0127]

[0128] In the formula, is the desired force, is the contact force, is the inertia coefficient matrix, is the damping coefficient matrix, is the stiffness coefficient matrix, , , are respectively the desired acceleration vector, desired velocity, and desired position of the end effector, , , They are respectively the acceleration vector, velocity, and position of the end effector.

[0129] When the contact force is the axial contact force, for axial contact force control, and the inertia coefficient matrix , damping coefficient matrix , and stiffness coefficient matrix are positive definite matrices, select , , , , , , , , , , to replace , , , , , , , , , , to represent the variables and coefficients in the axial direction, and further simplify the dynamic equation of the end effector to:

[0130]

[0131] Take the Laplace transform of the above equation, and are respectively transformed into and , and are respectively transformed into and , and are respectively transformed into and , and are respectively transformed into and ; where s is the complex frequency in the Laplace transform, then there is:

[0132]

[0133] Simplify to get:

[0134]

[0135] Therefore, the force control position compensation prediction model is:

[0136]

[0137] Among them, denote , where as the predicted value of force-controlled position compensation.

[0138] It should be explained that in the above steps, the axial contact force is controlled. Among them, the control methods of the longitudinal contact force and the lateral contact force are the same as those of the axial contact force, which will not be elaborated here.

[0139] Step 105: Determine the displacement compensation amount according to the predicted value of vibration position compensation and the predicted value of force-controlled position compensation.

[0140] In one embodiment, determining the displacement compensation amount according to the predicted value of vibration position compensation and the predicted value of force-controlled position compensation includes:

[0141] Determine the displacement compensation amount according to the following formula:

[0142]

[0143] where is the displacement compensation amount, is the predicted value of vibration position compensation, is the predicted value of force-controlled position compensation.

[0144] Step 106: Input the displacement compensation amount into the position controller to perform position control on the end effector.

[0145] Figure 4 is a comparison diagram of the vibration amplitude of the workpiece during the grinding process using the conventional grinding method and the method of the embodiment of the present disclosure.

[0146] Now, the same specification of weakly rigid workpieces are ground using the conventional grinding method and the method of the embodiment of the present disclosure respectively. Among them, Figure 4 the upper curve in

[0147] Figure 5 is the vibration amplitude curve of the workpiece using the conventional grinding method (suppression off), and the lower curve is the vibration amplitude curve of the workpiece using the method of this embodiment (suppression on). Obviously, the method of this embodiment can effectively suppress the vibration generated by the weakly rigid workpiece during the grinding process. Figure 6 is the surface quality diagram of the weakly rigid workpiece ground using the conventional method;

[0148] From Figure 5 and Figure 6It can be seen that the surface quality of the weakly rigid workpiece polished by the method of this embodiment is significantly better than that polished by the conventional method, and the surface quality of the weakly rigid workpiece polished by the method of this embodiment has good consistency.

[0149] The embodiment of the present disclosure also provides a grinding vibration suppression device. Figure 7 As shown in the schematic diagram of the grinding vibration suppression device provided by the embodiment of the present disclosure, Figure 7 as shown, the device includes:

[0150] The first acquisition unit 701 is configured to acquire the original vibration data during the grinding process of the workpiece;

[0151] The first determination unit 702 is configured to input the original vibration data into the vibration position compensation prediction model to determine the vibration position compensation prediction value;

[0152] The second acquisition unit 703 is configured to acquire the contact force during the grinding process of the workpiece;

[0153] The second determination unit 704 is configured to input the contact force into the force control position compensation model to determine the force control position compensation prediction value;

[0154] The third determination unit 705 is configured to determine the displacement compensation amount according to the vibration position compensation prediction value and the force control position compensation prediction value;

[0155] The control unit 706 is configured to input the displacement compensation amount into the position controller to perform position control on the end effector.

[0156] In one embodiment, the first determination unit 702 includes:

[0157] The first sub-determination unit is configured to execute step S1 to determine the first vibration mode function of the original vibration data according to empirical mode decomposition;

[0158] The second sub-determination unit is configured to execute step S2 to eliminate the first vibration mode function from the original vibration data and determine the first function;

[0159] The first sub-judgment unit is configured to execute step S3 to judge whether the mean curve of the upper envelope line and the lower envelope line of the first function is a monotonic function;

[0160] If it is a monotonic function, substitute the first vibration mode function into the vibration position compensation prediction model to determine the vibration position compensation prediction value;

[0161] If it is not a monotonic function, take the first function as the new original vibration data, and repeat steps S1 to S3 until the p-th vibration mode function and the p-th function are obtained. The mean curve of the upper envelope line and the lower envelope line of the p-th function is a monotonic function;

[0162] A selection unit, configured to execute step S4, and select the three vibration mode functions with the highest frequencies among the first vibration mode function to the p-th vibration mode function;

[0163] A third sub-determination unit, configured to execute step S5, substitute the three vibration mode functions with the highest frequencies into the vibration position compensation prediction model to determine the vibration position compensation prediction value.

[0164] In one embodiment, the first sub-determination unit includes:

[0165] A fourth sub-determination unit, configured to execute step S1-1, and determine the upper envelope line composed of all the maximum value points of the original vibration data and the lower envelope line composed of all the minimum value points of the original vibration data according to the original vibration data;

[0166] A fifth sub-determination unit, configured to execute step S1-2, and determine the original vibration mode function of the original vibration data according to the upper envelope line and the lower envelope line;

[0167] A second sub-judgment unit, configured to execute step S1-3, and judge whether the original vibration mode function satisfies the following two conditions:

[0168] Condition 1: The mean value of the upper envelope line and the lower envelope line at any time is zero;

[0169] Condition 2: The number of times exceeding zero is equal to or differs by one from the number of extreme value points;

[0170] If the original vibration mode function simultaneously satisfies the above Conditions 1 and 2, record the original vibration mode function as the first vibration mode function;

[0171] If the original vibration mode function does not simultaneously satisfy Conditions 1 and 2, take the original vibration mode function as the new original vibration data, and re-execute steps S1-1 to S1-3 until the finally obtained vibration mode function satisfies Conditions 1 and 2,

[0172] A sixth sub-determination unit, configured to execute step S1-4: Record the finally obtained vibration mode function that satisfies Conditions 1 and 2 as the first vibration mode function.

[0173] In one embodiment, the third sub-determination unit includes:

[0174] A transformation unit, configured to perform Fourier transform on the three vibration mode functions with the highest frequencies;

[0175] The first sub-acquisition unit is configured to respectively acquire the maximum amplitudes of the three vibration mode functions after Fourier transform;

[0176] The seventh sub-determination unit is configured to substitute the maximum amplitude into the vibration position compensation prediction model to determine the vibration position compensation prediction value.

[0177] In one embodiment, the second determination unit 704 includes:

[0178] The eighth sub-determination unit is configured to determine the dynamic equation of the end effector according to the dynamic model of the end effector;

[0179] The obtaining unit is configured to perform Laplace transform on the dynamic equation to obtain the force control position compensation prediction model;

[0180] The ninth sub-determination unit is configured to determine the force control position compensation prediction value according to the force control position compensation prediction model.

[0181] According to an embodiment of the present disclosure, the present disclosure also provides an electronic device and a readable storage medium.

[0182] Figure 8 FIG. shows a schematic block diagram of an exemplary electronic device 800 that can be used to implement the embodiments of the present disclosure. The electronic device is intended to represent various forms of digital computers, such as, a laptop computer, a desktop computer, a workbench, a personal digital assistant, a server, a blade server, a mainframe computer, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as, a personal digital processor, a cellular phone, a smart phone, a wearable device, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present disclosure described and / or claimed herein.

[0183] As Figure 8 shown, the device 800 includes a computing unit 801, which can perform various appropriate actions and processes according to the computer program stored in the read-only memory (ROM) 802 or the computer program loaded from the storage unit 808 into the random access memory (RAM) 803. In the RAM 803, various programs and data required for the operation of the device 800 can also be stored. The computing unit 801, the ROM 802, and the RAM 803 are connected to each other through a bus 804. The input / output (I / O) interface 805 is also connected to the bus 804.

[0184] Multiple components in device 800 are connected to I / O interface 805, including: input unit 806, such as a keyboard, mouse, etc.; output unit 807, such as various types of displays, speakers, etc.; storage unit 808, such as a disk, optical disc, etc.; and communication unit 809, such as a network card, modem, wireless communication transceiver, etc. Communication unit 809 allows device 800 to exchange information / data with other devices via a computer network such as the Internet and / or various telecommunication networks.

[0185] Computing unit 801 can be various general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of computing unit 801 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. Computing unit 801 executes the various methods and processes described above, such as the grinding vibration suppression method. For example, in some embodiments, the grinding vibration suppression method can be implemented as a computer software program tangibly embodied in a machine-readable medium, such as storage unit 808. In some embodiments, part or all of the computer program can be loaded and / or installed onto device 800 via ROM 802 and / or communication unit 809. When the computer program is loaded into RAM 803 and executed by computing unit 801, one or more steps of the grinding vibration suppression method described above can be executed. Alternatively, in other embodiments, computing unit 801 can be configured to execute the grinding vibration suppression method in any other suitable manner (e.g., by means of firmware).

[0186] The various embodiments of the systems and techniques described above in this document can be implemented in digital electronic circuit systems, integrated circuit systems, field-programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), systems-on-a-chip (SOCs), complex programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various embodiments can include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special or general-purpose programmable processor, and can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit the data and instructions to the storage system, the at least one input device, and the at least one output device.

[0187] The program code for implementing the methods of the present disclosure can be written in any combination of one or more programming languages. These program codes can be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing devices, such that when the program codes are executed by the processor or controller, the functions / operations specified in the flowchart and / or block diagram are implemented. The program codes can be executed entirely on the machine, partially on the machine, executed partially on the machine and partially on a remote machine as an independent software package, or executed entirely on a remote machine or server.

[0188] In the context of the present disclosure, a machine-readable medium can be a tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device. A machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of a machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0189] In order to provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device for displaying information to the user (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor); and a keyboard and a pointing device (e.g., a mouse or a trackball) through which the user can provide input to the computer. Other kinds of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, voice input, or tactile input).

[0190] The systems and techniques described herein can be implemented in a computing system including backend components (e.g., as a data server), or a computing system including middleware components (e.g., an application server), or a computing system including frontend components (e.g., a user computer having a graphical user interface or a web browser through which a user can interact with an implementation of the systems and techniques described herein), or a computing system including any combination of such backend components, middleware components, or frontend components. The components of the system can be interconnected to each other by digital data communication in any form or medium (e.g., a communication network). Examples of communication networks include: local area network (LAN), wide area network (WAN), and the Internet.

[0191] A computer system can include a client and a server. The client and the server are generally far from each other and typically interact through a communication network. The client-server relationship is created by computer programs running on the respective computers and having a client-server relationship with each other. The server can be a cloud server, a server of a distributed system, or a server incorporating a blockchain.

[0192] It should be understood that various forms of the processes shown above can be used, steps can be reordered, added, or deleted. For example, the steps recited in this disclosure can be executed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions disclosed in this disclosure can be achieved, and no limitations are imposed herein.

[0193] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" can explicitly or implicitly include at least one such feature. In the description of this disclosure, "a plurality" means two or more, unless otherwise specifically defined.

[0194] As described above, the above are only specific embodiments of this disclosure, but the protection scope of this disclosure is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by this disclosure, and all should be covered by the protection scope of this disclosure. Therefore, the protection scope of this disclosure should be subject to the protection scope of the claimed rights.

Claims

1. A method for suppressing grinding vibration, characterized in that, The method includes: Obtaining the original vibration data during the workpiece grinding process; Inputting the original vibration data into a vibration position compensation prediction model to determine the vibration position compensation prediction value; Obtaining the contact force during the workpiece grinding process; Inputting the contact force into a force control position compensation model to determine the force control position compensation prediction value; Determining the displacement compensation amount according to the vibration position compensation prediction value and the force control position compensation prediction value; Inputting the displacement compensation amount into a position controller to perform position control on the end effector; The step of inputting the original vibration data into a vibration position compensation prediction model to determine the vibration position compensation prediction value includes: Step S1: Determining the first vibration mode function of the original vibration data according to empirical mode decomposition; Step S2: Eliminating the first vibration mode function from the original vibration data to determine the first function; Step S3: Judging whether the mean curve of the upper envelope line and the lower envelope line of the first function is a monotonic function; If it is a monotonic function, substituting the first vibration mode function into the vibration position compensation prediction model to determine the vibration position compensation prediction value; If it is not a monotonic function, using the first function as the new original vibration data, and repeating steps S1 to S3 until the p-th vibration mode function and the p-th function are obtained, and the mean curve of the upper envelope line and the lower envelope line of the p-th function is a monotonic function; Step S4: Selecting the three vibration mode functions with the highest frequencies among the first vibration mode function to the p-th vibration mode function; Step S5: Substituting the three vibration mode functions with the highest frequencies into the vibration position compensation prediction model to determine the vibration position compensation prediction value.

2. The method according to claim 1, wherein The step of determining the first vibration mode function of the original vibration data according to empirical mode decomposition includes: Step S1-1: Determining the upper envelope line composed of all the maximum points of the original vibration data and the lower envelope line composed of all the minimum points of the original vibration data according to the original vibration data; Step S1-2: Determining the original vibration mode function of the original vibration data according to the upper envelope line and the lower envelope line; Step S1-3: Judging whether the original vibration mode function satisfies the following two conditions: Condition 1: The mean values of the upper envelope line and the lower envelope line at any time are both zero; Condition 2: The number of points exceeding zero is equal to or differs by one from the number of extreme points; If the original vibration mode function simultaneously satisfies the above Condition 1 and Condition 2, then recording the original vibration mode function as the first vibration mode function; If the original vibration mode function does not simultaneously satisfy Condition 1 and Condition 2, then using the original vibration mode function as the new original vibration data and re-executing steps S1-1 to S1-3 until the finally obtained vibration mode function satisfies Condition 1 and Condition 2, Step S1-4: Recording the finally obtained vibration mode function that satisfies Condition 1 and Condition 2 as the first vibration mode function.

3. The method according to claim 1, wherein Substituting the three vibration mode functions with the highest frequencies into the vibration position compensation prediction model to determine the vibration position compensation prediction value includes: Performing Fourier transform on the three vibration mode functions with the highest frequencies; Respectively obtaining the maximum amplitudes of the three vibration mode functions after Fourier transform; Substituting the maximum amplitudes into the vibration position compensation prediction model to determine the vibration position compensation prediction value.

4. The method according to claim 3, wherein The vibration position compensation prediction model is shown by the following formula: Among them, is the predicted value of vibration position compensation, , , are proportionality coefficients, and 1, , , are the maximum amplitudes of the three vibration mode functions respectively.

5. The method according to claim 1, wherein Inputting the contact force into the force control position compensation model to determine the force control position compensation prediction value includes: Determining the dynamic equation of the end effector according to the dynamic model of the end effector; Performing Laplace transform on the dynamic equation to obtain the force control position compensation prediction model; Determining the force control position compensation prediction value according to the force control position compensation prediction model.

6. The method according to claim 1, wherein Determining the displacement compensation amount according to the vibration position compensation prediction value and the force control position compensation prediction value includes: Determining the displacement compensation amount according to the following formula: wherein, is the displacement compensation amount, is the predicted value of vibration position compensation, is the predicted value of force control position compensation.

7. A grinding vibration suppression device, characterized in that, The device includes: A first acquisition unit configured to acquire the original vibration data during workpiece grinding; A first determination unit configured to input the original vibration data into the vibration position compensation prediction model to determine the vibration position compensation prediction value; A second acquisition unit configured to acquire the contact force during workpiece grinding; A second determination unit configured to input the contact force into the force control position compensation model to determine the force control position compensation prediction value; A third determination unit configured to determine the displacement compensation amount according to the vibration position compensation prediction value and the force control position compensation prediction value; A control unit configured to input the displacement compensation amount into the position controller to perform position control on the end effector; The first determination unit includes: A first sub-determination unit configured to execute step S1 to determine the first vibration mode function of the original vibration data according to empirical mode decomposition; A second sub-determination unit configured to execute step S2 to eliminate the first vibration mode function from the original vibration data to determine the first function; A first sub-judgment unit configured to execute step S3 to judge whether the mean curve of the upper envelope line and the lower envelope line of the first function is a monotonic function; If it is a monotonic function, substituting the first vibration mode function into the vibration position compensation prediction model to determine the vibration position compensation prediction value; If it is not a monotonic function, using the first function as the new original vibration data, and repeating steps S1 to S3 until the p-th vibration mode function and the p-th function are obtained, and the mean curve of the upper envelope line and the lower envelope line of the p-th function is a monotonic function; A selection unit configured to execute step S4 to select the three vibration mode functions with the highest frequencies from the first vibration mode function to the p-th vibration mode function; A third sub-determination unit, configured to execute step S5, substitute the three vibration mode functions with the highest frequencies into the vibration position compensation prediction model, and determine the vibration position compensation prediction value.

8. An electronic device, characterized in that, Comprising: At least one processor; And A memory communicatively connected to the at least one processor; wherein, The memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to execute the method according to any one of claims 1-6.

9. A non-transitory computer-readable storage medium storing computer instructions, characterized in that, The computer instructions are used to cause a computer to execute the method according to any one of claims 1-6.

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