Industrial robot, control method and device thereof and readable storage medium

Abstract

The invention provides an industrial robot, a control method and device of the industrial robot and a readable storage medium, the industrial robot comprises a joint, a tail end flange and a vibration filter, and the control method comprises the steps that the corresponding relation between the pose of the tail end flange and vibration parameters of the joint in the global space is obtained; acquiring a first interpolation value output by the vibration filter in the previous interpolation period; based on the corresponding relation, matching a first vibration parameter corresponding to the first interpolation value; and controlling the vibration filter to work according to the operation parameter updated by the first vibration parameter.

Description

Technical Field

[0001] The present invention relates to the field of control technology, and in particular to an industrial robot and a control method, device and readable storage medium thereof. Background Art

[0002] Taking the robotic arm as an example, an industrial robot has a connecting load such as a reducer and a belt between its motor and connecting rod, which makes the motor and connecting rod of the robotic arm flexible. This flexibility is called joint flexibility.

[0003] Externally, the motor drives the connecting rod of the robotic arm with high responsiveness, which causes vibration in the connecting rod, greatly affecting a series of important performance indicators of the robotic arm, such as trajectory accuracy and arrival time. The actual consequence is that the robotic arm cannot complete the user's instructions at high speed and high precision due to vibration, and cannot create more value for the user. At the same time, vibration will reduce the service life of the robotic arm.

[0004] To ensure that the robotic arm can operate with high control accuracy, the joint stiffness of the robotic arm will be calibrated to establish a rigid-flexible dynamic model of the joint based on the calibration results. The motion planning trajectory needs to be shaped by the rigid-flexible dynamic model before it can be sent to the joint driver.

[0005] However, the joint stiffness and torque present a nonlinear joint, and the calibration process is complicated and costly. Summary of the Invention

[0006] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0007] To this end, a first aspect of the present invention is to provide a control method for an industrial robot.

[0008] A second aspect of the present invention is to provide a control device for an industrial robot.

[0009] A third aspect of the present invention is to provide another control device for an industrial robot.

[0010] A fourth aspect of the present invention provides a readable storage medium.

[0011] A fifth aspect of the present invention is to provide an industrial robot.

[0012] In view of this, according to a first aspect of the present invention, a control method for an industrial robot is provided. The industrial robot includes a joint, an end flange and a vibration filter. The control method includes: obtaining a correspondence between the posture of the end flange and the vibration parameters of the joint in a global space; obtaining a first interpolation value output by the vibration filter in a previous interpolation cycle; matching a first vibration parameter corresponding to the first interpolation value based on the correspondence; and controlling the vibration filter to operate according to the operating parameters updated by the first vibration parameter.

[0013] The present invention proposes a control method for an industrial robot. By running the above control method, the operating parameters of a vibration filter can be updated based on the determined first vibration parameters, so that when the vibration filter operates according to the updated operating parameters, the vibration of the motor can be suppressed, thereby ensuring the control accuracy of the industrial robot.

[0014] In related technical solutions, calibrating the joint stiffness of an industrial robot requires the user to pay the manufacturer, who then equips the robot with expensive equipment to calibrate the robot and obtain calibration parameters. However, the industrial robot control method proposed in the present invention allows the robot to directly achieve vibration suppression by executing the control method, eliminating the need to calibrate the joint stiffness of the robot, thereby reducing the cost of vibration suppression for the robot.

[0015] At the same time, the control method proposed in the present invention can quickly suppress joint vibration according to on-site working conditions without waiting for manufacturer calibration, thereby minimizing the impact of vibration on the operation of industrial robots.

[0016] In addition, the control method for the industrial robot proposed in the present invention does not require the construction of a rigid-flexible dynamics model, and also reduces the workload required for the industrial robot to suppress vibration.

[0017] The embodiment of the present invention is implemented based on the following principles. Specifically, by obtaining the correspondence between the posture of the end flange and the vibration parameters of the joint in the global space, after obtaining the first interpolation value output by the vibration filter in the previous interpolation cycle, the above correspondence can be used to determine the first vibration parameter corresponding to the first interpolation value.

[0018] In the above technical solution, since the first vibration parameter is determined based on the above correspondence, the first vibration parameter can characterize the vibration condition of the joint. Therefore, after using the first vibration parameter to update the operating parameters of the vibration filter, when the vibration filter operates according to the updated operating parameters, the vibration of the motor can be suppressed, thereby ensuring the control accuracy of the industrial robot.

[0019] In some technical solutions, optionally, the end flange can be understood as a flange used to connect to an end effector in an industrial robot.

[0020] In addition, the control method of the industrial robot proposed in the present invention also has the following additional technical features.

[0021] In some technical solutions, optionally, the end flange is connected to the end effector, and based on the corresponding relationship, the first vibration parameter corresponding to the first interpolation value is matched, specifically including: determining the first position information of the end effector in the workspace based on the first interpolation value; determining the first posture corresponding to the first position information, the first posture is the posture of the end flange; based on the corresponding relationship, determining the first vibration parameter corresponding to the first posture.

[0022] In this technical solution, considering that the control of the industrial robot is based on the end effector as the control object, the first interpolation value is also given for the control of the end effector. Therefore, in the technical solution of the present invention, based on the first interpolation value, the first position information of the end effector in the workspace is determined, and the first position corresponding to the first position information of the end effector in the workspace is found, and the above-mentioned correspondence is used to find the first vibration parameter corresponding to the first posture.

[0023] During this process, conversion can be performed between the end effector and the end flange to ensure that the obtained first vibration parameter matches the first interpolation value. Obviously, when the first vibration parameter matches the first interpolation value, the accuracy of the first vibration parameter can be ensured, thereby achieving accurate suppression of the vibration of the motor.

[0024] In some technical solutions, optionally, the vibration filter includes a first sub-vibration filter and a second sub-vibration filter, and the output value of the first sub-vibration filter is input into the second sub-vibration filter, and based on the correspondence, the first vibration parameter corresponding to the first interpolation value is matched, specifically including: matching the first vibration frequency and the first damping corresponding to the first interpolation value based on the correspondence; matching the second vibration frequency and the second damping corresponding to the first interpolation value based on the correspondence; wherein the first sub-vibration filter updates the operating parameters based on the first vibration frequency and the first damping, and the second sub-vibration filter updates the operating parameters based on the second vibration frequency and the second damping.

[0025] In this technical solution, the vibration filter adopts a second-order filter, that is, it includes a first sub-vibration filter and a second sub-vibration filter. In the technical solution proposed in the present invention, the first vibration frequency, the first damping, the second vibration frequency and the second damping can be matched based on the corresponding relationship, wherein the first vibration frequency and the first damping act on the first sub-vibration filter, and the second vibration frequency and the second damping act on the second sub-vibration filter.

[0026] Obviously, the first sub-vibration filter and the second sub-vibration filter can be used to filter two different frequencies, thereby eliminating the vibration generated by the joint and improving the control accuracy of the industrial robot.

[0027] In some technical solutions, the first damping and the second damping may be an anti-resonance damping coefficient and a resonance damping coefficient.

[0028] Correspondingly, the first vibration frequency is the anti-resonance frequency, and the second vibration frequency is the resonant frequency.

[0029] In some technical solutions, optionally, the correspondence between the position and posture of the end flange and the vibration parameters of the joint in the global space is obtained, specifically including: obtaining the vibration parameters of the joint when the end flange traverses discrete points in the global space to obtain the correspondence; wherein, when the end flange moves from a first discrete point to a second discrete point, the joint operates according to a speed curve corresponding to the second discrete point to obtain the vibration parameters of the joint, and the first discrete point and the second discrete point are discrete points adjacent to the path in the global space.

[0030] In this technical solution, the vibration parameters of the joints are obtained at discrete points in the global space so that resonance suppression can be achieved under different planned paths of the industrial robot, thereby ensuring the control accuracy of the industrial robot.

[0031] In some technical solutions, optionally, the control method further includes: acquiring recognition space information and recognition space distance information; and determining discrete points in the global space based on the recognition space information and the recognition space distance information.

[0032] In this technical solution, the identification space information can be understood as the spatial information in which the end flange can move in the global space, and the identification space distance information can be understood as the minimum distance in which the end flange can move in the global space. By obtaining the identification space information and the identification space distance information, all the points in which the end flange can appear in the global space can be determined based on the identification space information and the identification space distance information, and then all the points in which the end flange can appear in the global space are regarded as discrete points.

[0033] In this technical solution, the vibration parameters of all possible positions of the end flange of the industrial robot can be measured, and then the vibration of the joint can be suppressed in the global space to ensure the control accuracy of the industrial robot.

[0034] In some technical solutions, optionally, the control method further includes: determining a position offset based on the identification space distance information; and planning a speed curve based on the position offset.

[0035] In this technical solution, the velocity curve can be determined based on the position offset determined by the identification space distance information. In this process, the velocity curve can be well matched with the vibration generated by the excited joint, thereby stimulating the joint vibration to the greatest extent.

[0036] According to a second aspect of the present invention, the present invention provides a control device for an industrial robot, wherein the industrial robot includes a joint, an end flange, and a vibration filter, and the control device includes: a first acquisition unit, for acquiring the correspondence between the posture of the end flange and the vibration parameters of the joint in a global space; a second acquisition unit, for acquiring a first interpolation value output by the vibration filter in a previous interpolation cycle; a matching unit, for matching the first vibration parameter corresponding to the first interpolation value based on the correspondence; and a control unit, for controlling the vibration filter to operate according to the operating parameters updated by the first vibration parameter.

[0037] The present invention proposes a control device for an industrial robot, which can update the operating parameters of a vibration filter based on a determined first vibration parameter, so that when the vibration filter operates according to the updated operating parameters, the vibration of the motor can be suppressed, thereby ensuring the control accuracy of the industrial robot.

[0038] In related technical solutions, calibrating the joint stiffness of an industrial robot requires the user to pay the manufacturer, who then equips the robot with expensive equipment to calibrate the robot and obtain calibration parameters. However, the industrial robot control method proposed in the present invention allows the robot to directly achieve vibration suppression by executing the control method, eliminating the need to calibrate the joint stiffness of the robot, thereby reducing the cost of vibration suppression for the robot.

[0039] At the same time, the control method proposed in the present invention can quickly suppress joint vibration according to on-site working conditions without waiting for manufacturer calibration, thereby minimizing the impact of vibration on the operation of industrial robots.

[0040] In addition, the control method for the industrial robot proposed in the present invention does not require the construction of a rigid-flexible dynamics model, and also reduces the workload required for the industrial robot to suppress vibration.

[0041] The embodiment of the present invention is implemented based on the following principles. Specifically, by obtaining the correspondence between the posture of the end flange and the vibration parameters of the joint in the global space, after obtaining the first interpolation value output by the vibration filter in the previous interpolation cycle, the above correspondence can be used to determine the first vibration parameter corresponding to the first interpolation value.

[0042] In the above technical solution, since the first vibration parameter is determined based on the above correspondence, the first vibration parameter can characterize the vibration condition of the joint. Therefore, after using the first vibration parameter to update the operating parameters of the vibration filter, when the vibration filter operates according to the updated operating parameters, the vibration of the motor can be suppressed, thereby ensuring the control accuracy of the industrial robot.

[0043] In some technical solutions, optionally, the end flange can be understood as a flange used to connect to an end effector in an industrial robot.

[0044] In addition, the control device for the industrial robot proposed in the present invention also has the following additional technical features.

[0045] In some technical solutions, optionally, the end flange is connected to an end effector, and the matching unit is specifically used to: determine the first position information of the end effector in the workspace based on the first interpolation value; determine the first posture corresponding to the first position information, the first posture is the posture of the end flange; based on the corresponding relationship, determine the first vibration parameter corresponding to the first posture.

[0046] In this technical solution, considering that the control of the industrial robot is based on the end effector as the control object, the first interpolation value is also given for the control of the end effector. Therefore, in the technical solution of the present invention, based on the first interpolation value, the first position information of the end effector in the workspace is determined, and the first position corresponding to the first position information of the end effector in the workspace is found, and the above-mentioned correspondence is used to find the first vibration parameter corresponding to the first posture.

[0047] During this process, conversion can be performed between the end effector and the end flange to ensure that the obtained first vibration parameter matches the first interpolation value. Obviously, when the first vibration parameter matches the first interpolation value, the accuracy of the first vibration parameter can be ensured, thereby achieving accurate suppression of the vibration of the motor.

[0048] In some technical solutions, optionally, the vibration filter includes a first sub-vibration filter and a second sub-vibration filter, the output value of the first sub-vibration filter is input into the second sub-vibration filter, and the matching unit is specifically used to: match the first vibration frequency and the first damping corresponding to the first interpolation value based on the corresponding relationship; match the second vibration frequency and the second damping corresponding to the first interpolation value based on the corresponding relationship; wherein the first sub-vibration filter updates the operating parameters based on the first vibration frequency and the first damping, and the second sub-vibration filter updates the operating parameters based on the second vibration frequency and the second damping.

[0049] In this technical solution, the vibration filter adopts a second-order filter, that is, it includes a first sub-vibration filter and a second sub-vibration filter. In the technical solution proposed in the present invention, the first vibration frequency, the first damping, the second vibration frequency and the second damping can be matched based on the corresponding relationship, wherein the first vibration frequency and the first damping act on the first sub-vibration filter, and the second vibration frequency and the second damping act on the second sub-vibration filter.

[0050] Obviously, the first sub-vibration filter and the second sub-vibration filter can be used to filter two different frequencies, thereby eliminating the vibration generated by the joint and improving the control accuracy of the industrial robot.

[0051] In some technical solutions, the first damping and the second damping may be an anti-resonance damping coefficient and a resonance damping coefficient.

[0052] Correspondingly, the first vibration frequency is the anti-resonance frequency, and the second vibration frequency is the resonant frequency.

[0053] In some technical solutions, optionally, the first acquisition unit is specifically used to: obtain the vibration parameters of the joint when the end flange traverses discrete points in the global space to obtain a corresponding relationship; wherein, when the end flange moves from a first discrete point to a second discrete point, the joint operates according to a speed curve corresponding to the second discrete point to obtain the vibration parameters of the joint, and the first discrete point and the second discrete point are adjacent discrete points on the path in the global space.

[0054] In this technical solution, the vibration parameters of the joints are obtained at discrete points in the global space so that resonance suppression can be achieved under different planned paths of the industrial robot, thereby ensuring the control accuracy of the industrial robot.

[0055] In some technical solutions, optionally, the first acquisition unit is further used to: acquire recognition space information and recognition space distance information; and determine discrete points in the global space based on the recognition space information and the recognition space distance information.

[0056] In this technical solution, the identification space information can be understood as the spatial information in which the end flange can move in the global space, and the identification space distance information can be understood as the minimum distance in which the end flange can move in the global space. By obtaining the identification space information and the identification space distance information, all the points in which the end flange can appear in the global space can be determined based on the identification space information and the identification space distance information, and then all the points in which the end flange can appear in the global space are regarded as discrete points.

[0057] In this technical solution, the vibration parameters of all possible positions of the end flange of the industrial robot can be measured, and then the vibration of the joint can be suppressed in the global space to ensure the control accuracy of the industrial robot.

[0058] In some technical solutions, optionally, the first acquisition unit is further used to: determine a position offset based on the identification space distance information; and plan a speed curve based on the position offset.

[0059] In this technical solution, the velocity curve can be determined based on the position offset determined by the identification space distance information. In this process, the velocity curve can be well matched with the vibration generated by the excited joint, thereby stimulating the joint vibration to the greatest extent.

[0060] According to a third aspect of the present invention, the present invention provides a control device for an industrial robot, comprising a processor and a memory, wherein the memory stores programs or instructions that can be run on the processor, and when the programs or instructions are executed by the processor, the steps of any of the above methods are implemented.

[0061] According to a fourth aspect of the present invention, the present invention provides a readable storage medium, on which a program or instruction is stored, and when the program or instruction is executed by a processor, the steps of any of the above methods are implemented.

[0062] According to a fifth aspect of the present invention, the present invention provides an industrial robot, comprising: a control device as any one of the above industrial robots; and / or a readable storage medium as described above.

[0063] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments with reference to the accompanying drawings, in which:

[0065] Figure 1 A schematic flow chart of a control method for an industrial robot according to an embodiment of the present invention is shown;

[0066] Figure 2 A schematic block diagram of an industrial robot according to an embodiment of the present invention is shown;

[0067] Figure 3 A schematic diagram of a process for controlling a vibration filter based on a posture-vibration parameter mapping table in an embodiment of the present invention is shown;

[0068] Figure 4 A schematic structural diagram of an industrial robot according to an embodiment of the present invention is shown;

[0069] Figure 5 A schematic diagram of a process for generating a posture-vibration parameter mapping table in an embodiment of the present invention is shown;

[0070] Figure 6 A schematic block diagram of a control device for an industrial robot according to an embodiment of the present invention is shown;

[0071] Figure 7 A schematic block diagram of another control device for an industrial robot in an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0072] In order to more clearly understand the above aspects, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features therein can be combined with each other in the absence of conflict.

[0073] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the scope of protection of the present invention is not limited to the specific embodiments disclosed below.

[0074] In one embodiment of the present application, Figure 1 As shown and Figure 2 As shown, a control method for an industrial robot is provided. The industrial robot 200 includes a joint 202, an end flange 204, and a vibration filter 206. The control method includes:

[0075] Step 102: Obtain the corresponding relationship between the position and posture of the end flange and the vibration parameters of the joint in the global space;

[0076] Step 104, obtaining a first interpolation value output by the vibration filter in the previous interpolation cycle;

[0077] Step 106, matching the first vibration parameter corresponding to the first interpolation value based on the corresponding relationship;

[0078] Step 108: Control the vibration filter to operate according to the operating parameters updated by the first vibration parameter.

[0079] The present invention proposes a control method for an industrial robot. By running the above control method, the operating parameters of a vibration filter can be updated based on the determined first vibration parameters, so that when the vibration filter operates according to the updated operating parameters, the vibration of the motor can be suppressed, thereby ensuring the control accuracy of the industrial robot.

[0080] In related technical solutions, calibrating the joint stiffness of an industrial robot requires the user to pay the manufacturer, who then equips the robot with expensive equipment to calibrate the robot and obtain calibration parameters. However, the industrial robot control method proposed in the present invention allows the robot to directly achieve vibration suppression by executing the control method, eliminating the need to calibrate the joint stiffness of the robot, thereby reducing the cost of vibration suppression for the robot.

[0081] At the same time, the control method proposed in the present invention can quickly suppress joint vibration according to on-site working conditions without waiting for manufacturer calibration, thereby minimizing the impact of vibration on the operation of industrial robots.

[0082] In addition, the control method for the industrial robot proposed in the present invention does not require the construction of a rigid-flexible dynamics model, and also reduces the workload required for the industrial robot to suppress vibration.

[0083] The embodiment of the present invention is implemented based on the following principles. Specifically, by obtaining the correspondence between the posture of the end flange and the vibration parameters of the joint in the global space, after obtaining the first interpolation value output by the vibration filter in the previous interpolation cycle, the above correspondence can be used to determine the first vibration parameter corresponding to the first interpolation value.

[0084] In the above embodiment, since the first vibration parameter is determined based on the above correspondence, the first vibration parameter can characterize the vibration condition of the joint. Therefore, after using the first vibration parameter to update the operating parameters of the vibration filter, when the vibration filter operates according to the updated operating parameters, the vibration of the motor can be suppressed, thereby ensuring the control accuracy of the industrial robot.

[0085] In some embodiments, optionally, the end flange can be understood as a flange used to connect to an end effector in an industrial robot.

[0086] In some embodiments, optionally, the end flange 204 is connected to the end effector 208, and based on the corresponding relationship, the first vibration parameter corresponding to the first interpolation value is matched, specifically including: determining the first position information of the end effector in the workspace based on the first interpolation value; determining the first posture corresponding to the first position information, the first posture being the posture of the end flange; and determining the first vibration parameter corresponding to the first posture based on the corresponding relationship.

[0087] In this embodiment, considering that the control of the industrial robot is based on the end effector as the control object, the first interpolation value is also given for the control of the end effector. Therefore, in an embodiment of the present invention, based on the first interpolation value, the first position information of the end effector in the workspace is determined, and the first position corresponding to the first position information of the end effector in the workspace is found, and the above correspondence is used to find the first vibration parameter corresponding to the first posture.

[0088] During this process, conversion can be performed between the end effector and the end flange to ensure that the obtained first vibration parameter matches the first interpolation value. Obviously, when the first vibration parameter matches the first interpolation value, the accuracy of the first vibration parameter can be ensured, thereby achieving accurate suppression of the vibration of the motor.

[0089] In some embodiments, optionally, the vibration filter includes a first sub-vibration filter and a second sub-vibration filter, the output value of the first sub-vibration filter is input into the second sub-vibration filter, and based on the correspondence, the first vibration parameter corresponding to the first interpolation value is matched, specifically including: based on the correspondence, matching the first vibration frequency and first damping corresponding to the first interpolation value; based on the correspondence, matching the second vibration frequency and second damping corresponding to the first interpolation value; wherein, the first sub-vibration filter updates the operating parameters based on the first vibration frequency and the first damping, and the second sub-vibration filter updates the operating parameters based on the second vibration frequency and the second damping.

[0090] In this embodiment, the vibration filter adopts a second-order filter, that is, it includes a first sub-vibration filter and a second sub-vibration filter. In the embodiment proposed in the present invention, the first vibration frequency, the first damping, the second vibration frequency and the second damping can be matched based on the corresponding relationship, wherein the first vibration frequency and the first damping act on the first sub-vibration filter, and the second vibration frequency and the second damping act on the second sub-vibration filter.

[0091] Obviously, the first sub-vibration filter and the second sub-vibration filter can be used to filter two different frequencies, thereby eliminating the vibration generated by the joint and improving the control accuracy of the industrial robot.

[0092] In some embodiments, the first damping and the second damping may be an anti-resonance damping coefficient and a resonance damping coefficient.

[0093] Correspondingly, the first vibration frequency is the anti-resonance frequency, and the second vibration frequency is the resonant frequency.

[0094] Specifically, the vibration filter is set in the two-mode vibration filter. In each interpolation cycle, it completes the filtering of the issued position command to achieve the effect of vibration suppression. Its working principle is as follows:

[0095] For a two-inertia system, the transfer functions from the motor output torque τ to the motor position θ and to the connecting rod position q are:

[0096]

[0097]

[0098] Among them, J m is the inertia of the motor, w a ,ξ a ,w r ,ξ r are the anti-resonance frequency, anti-resonance damping coefficient, resonant frequency, and resonant damping coefficient, respectively. s is the Laplace operator and · is the dot product symbol.

[0099] According to the above two equations, the transfer function from q to θ can be obtained, which is expressed as follows:

[0100]

[0101] As can be seen from formula (3), this is a non-physical system. In order to obtain a stable transfer function, (3) is passed through a second-order Butterworth low-pass filter, that is, the vibration filter in the present invention, whose cutoff frequency can be set to be consistent with the joint bandwidth or greater than the joint bandwidth.

[0102] Set the Butterworth low-pass filter cutoff frequency to w c , then the final form of the vibration filter is:

[0103]

[0104] like Figure 3 As shown, the two-mode vibration filter further includes a filter and a buffer, wherein the buffer is used to store intermediate quantities of the calculation process.

[0105] Specifically, the buffer includes a first buffer, a second buffer and a third buffer. The output of the filter is stored in the first buffer and serves as the input of the first sub-vibration filter. The output of the first sub-vibration filter is stored in the second buffer and serves as the input of the second sub-vibration filter. The output of the second sub-vibration filter is stored in the third buffer, wherein the third buffer outputs the first interpolation value mentioned above.

[0106] The filter may be an infinite impulse response (IIR) filter or a non-recursive (FIR) filter, and its parameters depend on the joint bandwidth, such as being at least twice the joint bandwidth.

[0107] The two-mode vibration filter also includes L and H calculation modules, which calculate the working space position of the flange end according to the position interpolation output value of the previous cycle, that is, the first position information in the present invention.

[0108] The two-mode vibration filter also includes an interpolation calculation module for w,ξ. According to the flange end position, w,ξ at that position are interpolated from the posture-vibration parameter mapping table, input into the vibration filter, and the parameters of the vibration filter are calculated, thereby realizing a global vibration suppression algorithm.

[0109] Among them, the two-mode vibration filter also includes a joint bandwidth module, which determines a suitable value according to the response bandwidth of the driver to the position instruction and the bandwidth of the controller. This value acts on the filter and the vibration filter.

[0110] For example, in the case of i As the input of the filter, the first buffer stores [θ i-2 ,θ i-1 ,θ i ], [θ i-2 ,θ i-1 ,θ i ] is input to the first sub-vibration filter, and the first sub-vibration filter is used to interpolate the previous period z -1 The output interpolation value is filtered to obtain Will Input to the second sub-vibration filter, the second sub-vibration filter is used to interpolate the last period z -1 The output interpolation value is filtered to obtain And output through the third buffer

[0111] Among them, θ i-2 is θ i-1 The motor position in the previous interpolation cycle, θ i-1 is θ i The motor position in the previous interpolation cycle, The meaning expressed is the same as θ i-2 ,θ i-1 ,θ i The superscripts “**” and “*” are used only for differentiation.

[0112] The interpolation calculation module w, ξ is based on the posture-vibration parameter mapping table, that is, the corresponding relationship in the present invention, and interpolation calculation obtains ξ1, w1, ξ0, w0, wherein ξ0, w0 are also the first damping and the first vibration frequency in the present invention, and ξ1, w1 are also the second damping and the second vibration frequency in the present invention.

[0113] In some embodiments, optionally, the correspondence between the posture of the end flange and the vibration parameters of the joint in the global space is obtained, specifically including: obtaining the vibration parameters of the joint when the end flange traverses discrete points in the global space to obtain the correspondence; wherein, when the end flange moves from a first discrete point to a second discrete point, the joint operates according to a speed curve corresponding to the second discrete point to obtain the vibration parameters of the joint, and the first discrete point and the second discrete point are discrete points adjacent to the path in the global space.

[0114] In this embodiment, the vibration parameters of the joints are obtained at discrete points in the global space so that resonance suppression can be achieved in different planned paths of the industrial robot, thereby ensuring the control accuracy of the industrial robot.

[0115] In some embodiments, optionally, the control method further includes: acquiring recognition space information and recognition space distance information; and determining discrete points in the global space based on the recognition space information and the recognition space distance information.

[0116] In this embodiment, the identification space information can be understood as the spatial information in which the end flange can move in the global space, and the identification space distance information can be understood as the minimum distance in which the end flange can move in the global space. By obtaining the identification space information and the identification space distance information, all the points in which the end flange can appear in the global space can be determined based on the identification space information and the identification space distance information, and then all the points in which the end flange can appear in the global space are regarded as discrete points.

[0117] In this embodiment, the vibration parameters of all possible positions of the end flange of the industrial robot can be measured, and then the vibration of the joint can be suppressed in the global space to ensure the control accuracy of the industrial robot.

[0118] For example, Figure 4 The right-hand configuration of the robot arm shown in the figure uses the arm base coordinate as a reference to establish the X, Y, and Z coordinate systems, and set the range L0, L1 from the base coordinate origin to the end flange in the Y direction. n The range from the origin to the end flange in the A direction is H0,H m , then L0,L n ,H0,H m It is the identification space information in the present invention.

[0119] The identification distances ΔL and ΔH, i.e., the identification space distance information in the present invention, are set, and the chirality during identification is set for the inverse solution of discrete points.

[0120] Specifically, the controller obtains the discrete points [L0, L1, ...L i,…L n ]、[H0,H1,…H j ,…H m The two-axis pairs are paired to identify the workspace points within the space. The controller also sets the bandwidth of the first and second axis drivers to a larger value, primarily to increase the vibration amplitude and achieve a higher signal-to-noise ratio during data measurement and processing.

[0121] like Figure 5 As shown, the robot arm starts from point (L0, H0), first traverses L, then traverses H, and completes the vibration information measurement of all points. For example, an if function is used to traverse all points, such as using if=i<n and if=i<m for loop judgment to traverse all points.

[0122] For the vibration parameter measurement of each discrete point, the position offset is first randomly obtained. Random is a random function, between two space points (L i -δL,H j ),(L i +δL,H j ) to plan a triangular velocity curve in the joint space to maximize the vibration frequency of the first and second axes, and the acceleration is set to the default value of the robot arm acceleration.

[0123] Since the rotation axes of the first and second axes are in the same direction, the vibration of the second axis will be transmitted to the first axis. Similarly, the vibration of the first axis will be transmitted to the second axis. Therefore, only the vibration suppression of the first axis is required to complete the vibration suppression requirements of the first and second axes. However, the vibration frequencies of the first and second axes may be different, so the vibration suppression identification process must be able to complete the identification of the parameters of both frequencies. Similarly, it is necessary to suppress both vibration modes simultaneously. Based on this fact, only one axis needs to be processed during the identification and vibration suppression process.

[0124] When the excitation trajectory is sent to the driver, the position data of one axis joint is started to be received. After the trajectory is sent, the data acquisition is terminated after a delay of 0.5 seconds. The collected data is subjected to white noise filtering, non-delay high-frequency filtering, and fast Fourier transform to obtain the frequency response characteristics. The amplitude response curve is subjected to data identification to identify the effective vibration frequency and damping w0, ξ0, w1, ξ1, and a data pair (L i ,H j ,w0,ξ0,w1,ξ1), and store them for further processing.

[0125] Among them, L i ,H j Represents the point position of the i-th ΔL and the j-th ΔH, that is, the discrete point, w0, ξ0, w1, ξ1 are also the first frequency, first damping, second frequency and second damping mentioned above.

[0126] After the data pairs of all spatial discrete points are extracted, the data are processed for the second time so that the position of the points (L i ,H j ) changes smoothly, and finally a posture-vibration parameter mapping table is obtained, which is the corresponding relationship in the present invention.

[0127] In some embodiments, optionally, the control method further includes: determining a position offset based on the identification space distance information; and planning a speed curve based on the position offset.

[0128] In this embodiment, the velocity curve can be determined based on the position offset determined by identifying the spatial distance information. In this process, the velocity curve can be well matched with the vibration generated by the excited joint, thereby stimulating the joint vibration to the greatest extent.

[0129] The position offset is also referred to as δL above.

[0130] In one embodiment, Figure 6 As shown, the present invention provides a control device 600 for an industrial robot, wherein the industrial robot includes a joint, an end flange, and a vibration filter. The control device includes: a first acquisition unit 602, for acquiring a correspondence between a posture of the end flange and a vibration parameter of the joint in a global space; a second acquisition unit 604, for acquiring a first interpolation value output by the vibration filter in a previous interpolation cycle; a matching unit 606, for matching a first vibration parameter corresponding to the first interpolation value based on the correspondence; and a control unit 608, for controlling the vibration filter to operate according to operating parameters updated by the first vibration parameter.

[0131] The present invention proposes a control device 600 for an industrial robot, which can update the operating parameters of a vibration filter based on a determined first vibration parameter, so that when the vibration filter operates according to the updated operating parameters, it can suppress the vibration of the motor, thereby ensuring the control accuracy of the industrial robot.

[0132] In related technical solutions, calibrating the joint stiffness of an industrial robot requires the user to pay the manufacturer, who then equips the robot with expensive equipment to calibrate the robot and obtain calibration parameters. However, the industrial robot control method proposed in the present invention allows the robot to directly achieve vibration suppression by executing the control method, eliminating the need to calibrate the joint stiffness of the robot, thereby reducing the cost of vibration suppression for the robot.

[0133] At the same time, the control method proposed in the present invention can quickly suppress joint vibration according to on-site working conditions without waiting for manufacturer calibration, thereby minimizing the impact of vibration on the operation of industrial robots.

[0134] In addition, the control method for the industrial robot proposed in the present invention does not require the construction of a rigid-flexible dynamics model, and also reduces the workload required for the industrial robot to suppress vibration.

[0135] The embodiment of the present invention is implemented based on the following principles. Specifically, by obtaining the correspondence between the posture of the end flange and the vibration parameters of the joint in the global space, after obtaining the first interpolation value output by the vibration filter in the previous interpolation cycle, the above correspondence can be used to determine the first vibration parameter corresponding to the first interpolation value.

[0136] In the above embodiment, since the first vibration parameter is determined based on the above correspondence, the first vibration parameter can characterize the vibration condition of the joint. Therefore, after using the first vibration parameter to update the operating parameters of the vibration filter, when the vibration filter operates according to the updated operating parameters, the vibration of the motor can be suppressed, thereby ensuring the control accuracy of the industrial robot.

[0137] In some embodiments, optionally, the end flange can be understood as a flange used to connect to an end effector in an industrial robot.

[0138] In some embodiments, optionally, the end flange is connected to an end effector, and the matching unit 606 is specifically used to: determine the first position information of the end effector in the workspace based on the first interpolation value; determine the first posture corresponding to the first position information, the first posture is the posture of the end flange; based on the corresponding relationship, determine the first vibration parameter corresponding to the first posture.

[0139] In this embodiment, considering that the control of the industrial robot is based on the end effector as the control object, the first interpolation value is also given for the control of the end effector. Therefore, in an embodiment of the present invention, based on the first interpolation value, the first position information of the end effector in the workspace is determined, and the first position corresponding to the first position information of the end effector in the workspace is found, and the above correspondence is used to find the first vibration parameter corresponding to the first posture.

[0140] During this process, conversion can be performed between the end effector and the end flange to ensure that the obtained first vibration parameter matches the first interpolation value. Obviously, when the first vibration parameter matches the first interpolation value, the accuracy of the first vibration parameter can be ensured, thereby achieving accurate suppression of the vibration of the motor.

[0141] In some embodiments, optionally, the vibration filter includes a first sub-vibration filter and a second sub-vibration filter, the output value of the first sub-vibration filter is input to the second sub-vibration filter, and the matching unit 606 is specifically used to: match the first vibration frequency and the first damping corresponding to the first interpolation value based on the corresponding relationship; match the second vibration frequency and the second damping corresponding to the first interpolation value based on the corresponding relationship; wherein the first sub-vibration filter updates the operating parameters based on the first vibration frequency and the first damping, and the second sub-vibration filter updates the operating parameters based on the second vibration frequency and the second damping.

[0142] In this embodiment, the vibration filter adopts a second-order filter, that is, it includes a first sub-vibration filter and a second sub-vibration filter. In the embodiment proposed in the present invention, the first vibration frequency, the first damping, the second vibration frequency and the second damping can be matched based on the corresponding relationship, wherein the first vibration frequency and the first damping act on the first sub-vibration filter, and the second vibration frequency and the second damping act on the second sub-vibration filter.

[0143] Obviously, the first sub-vibration filter and the second sub-vibration filter can be used to filter two different frequencies, thereby eliminating the vibration generated by the joint and improving the control accuracy of the industrial robot.

[0144] In some embodiments, the first damping and the second damping may be an anti-resonance damping coefficient and a resonance damping coefficient.

[0145] Correspondingly, the first vibration frequency is the anti-resonance frequency, and the second vibration frequency is the resonant frequency.

[0146] In some embodiments, optionally, the first acquisition unit 602 is specifically used to: obtain the vibration parameters of the joint when the end flange traverses discrete points in the global space to obtain a corresponding relationship; wherein, when the end flange moves from a first discrete point to a second discrete point, the joint operates according to a speed curve corresponding to the second discrete point to obtain the vibration parameters of the joint, and the first discrete point and the second discrete point are discrete points adjacent to the path in the global space.

[0147] In this embodiment, the vibration parameters of the joints are obtained at discrete points in the global space so that resonance suppression can be achieved in different planned paths of the industrial robot, thereby ensuring the control accuracy of the industrial robot.

[0148] In some embodiments, optionally, the first acquiring unit 602 is further configured to: acquire recognition space information and recognition space distance information; and determine discrete points in the global space based on the recognition space information and the recognition space distance information.

[0149] In this embodiment, the identification space information can be understood as the spatial information in which the end flange can move in the global space, and the identification space distance information can be understood as the minimum distance in which the end flange can move in the global space. By obtaining the identification space information and the identification space distance information, all the points in which the end flange can appear in the global space can be determined based on the identification space information and the identification space distance information, and then all the points in which the end flange can appear in the global space are regarded as discrete points.

[0150] In this embodiment, the vibration parameters of all possible positions of the end flange of the industrial robot can be measured, and then the vibration of the joint can be suppressed in the global space to ensure the control accuracy of the industrial robot.

[0151] In some embodiments, optionally, the first acquiring unit 602 is further configured to: determine a position offset based on the identification space distance information; and plan a speed curve based on the position offset.

[0152] In this embodiment, the velocity curve can be determined based on the position offset determined by identifying the spatial distance information. In this process, the velocity curve can be well matched with the vibration generated by the excited joint, thereby stimulating the joint vibration to the greatest extent.

[0153] In one embodiment, Figure 7 As shown, the present invention provides a control device 700 for an industrial robot, including a processor 702 and a memory 704. The memory 704 stores programs or instructions that can be run on the processor 702. When the programs or instructions are executed by the processor, the steps of any of the above methods are implemented.

[0154] The memory 704 can be used to store software programs and various data. The memory 704 mainly includes a first storage area for storing programs or instructions and a second storage area for storing data. The first storage area can store an operating system, applications or instructions required for at least one function (such as a sound playback function, an image playback function, etc.). In addition, the memory 704 can include a volatile memory or a non-volatile memory, or the memory can include both volatile and non-volatile memories. The non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. Volatile memory can be random access memory (RAM), static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM) and direct RAM bus random access memory (DRRAM). The memory in the embodiments of the present application includes but is not limited to these and any other suitable types of memory.

[0155] In one embodiment, the present invention provides a readable storage medium storing a program or instruction. When the program or instruction is executed by a processor, the steps of any one of the above methods are implemented.

[0156] In one embodiment, the present invention provides an industrial robot, comprising: a control device as any of the above industrial robots; and / or a readable storage medium as described above.

[0157] The terms "first" and "second" in the specification and claims of this application may explicitly or implicitly refer to one or more of the features. In the description of the present invention, unless otherwise specified, "plurality" means two or more. Furthermore, "and / or" in the specification and claims refers to at least one of the connected entities, and the character " / " generally indicates an "or" relationship between the connected entities.

[0158] In the description of the present invention, it is understood that, unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be interpreted broadly. For example, they may refer to fixed connection, detachable connection, or integral connection; mechanical connection or electrical connection; direct connection between two components or indirect connection through an intermediate medium; or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0159] In the claims, specification, and drawings of the present invention, the terms "one embodiment," "some embodiments," "a specific embodiment," and the like mean that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In the claims, specification, and drawings of the present invention, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0160] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A control method for an industrial robot, characterized in that: The industrial robot includes a joint, an end flange and a vibration filter, and the control method includes: Obtaining a corresponding relationship between the position and posture of the end flange and the vibration parameters of the joint in a global space; Acquire a first interpolation value output by the vibration filter in a previous interpolation cycle; Based on the corresponding relationship, matching the first vibration parameter corresponding to the first interpolation value; The vibration filter is controlled to operate according to the operating parameters updated by the first vibration parameter.

2. The control method of the industrial robot according to claim 1, characterized in that: The end flange is connected to an end effector, and matching the first vibration parameter corresponding to the first interpolation value based on the corresponding relationship specifically includes: determining first position information of the end effector in a workspace based on the first interpolation value; Determining a first pose corresponding to the first position information, where the first pose is the pose of the end flange; Based on the corresponding relationship, a first vibration parameter corresponding to the first posture is determined.

3. The control method of the industrial robot according to claim 1, characterized in that: The vibration filter includes a first sub-vibration filter and a second sub-vibration filter, an output value of the first sub-vibration filter is input to the second sub-vibration filter, and matching the first vibration parameter corresponding to the first interpolation value based on the corresponding relationship specifically includes: Based on the corresponding relationship, matching the first vibration frequency and the first damping corresponding to the first interpolation value; Based on the corresponding relationship, matching the second vibration frequency and the second damping corresponding to the first interpolation value; The first sub-vibration filter updates its operating parameters based on the first vibration frequency and the first damping, and the second sub-vibration filter updates its operating parameters based on the second vibration frequency and the second damping.

4. The control method of an industrial robot according to any one of claims 1 to 3, characterized in that: The obtaining of the correspondence between the position and posture of the end flange and the vibration parameters of the joint in the global space specifically includes: Obtaining vibration parameters of the joint when the end flange traverses discrete points in the global space to obtain the corresponding relationship; In which, when the end flange moves from a first discrete point to a second discrete point, the joint operates according to a velocity curve corresponding to the second discrete point to obtain the vibration parameters of the joint, and the first discrete point and the second discrete point are adjacent discrete points on the path in the global space.

5. The control method of the industrial robot according to claim 4, characterized in that: The control method further includes: Acquiring recognition space information and recognition space distance information; The discrete points in the global space are determined based on the recognition space information and the recognition space distance information.

6. The control method of the industrial robot according to claim 5, characterized in that: The control method further includes: determining a position offset based on the identification space distance information; The speed profile is planned based on the position offset.

7. A control device for an industrial robot, characterized in that: The industrial robot includes a joint, an end flange and a vibration filter, and the control device includes: A first acquiring unit is configured to acquire a corresponding relationship between the posture of the end flange and the vibration parameters of the joint in a global space; a second acquiring unit, configured to acquire a first interpolation value output by the vibration filter in a previous interpolation cycle; a matching unit, configured to match a first vibration parameter corresponding to the first interpolated value based on the corresponding relationship; A control unit is used to control the vibration filter to operate according to the operating parameters updated by the first vibration parameter.

8. A control device for an industrial robot, characterized in that: The method comprises a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of the method according to any one of claims 1 to 6 are implemented.

9. A readable storage medium, characterized in that: The readable storage medium stores a program or instruction, and when the program or instruction is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

10. An industrial robot, characterized in that: include: The control device of the industrial robot according to claim 7 or 8; and / or The readable storage medium according to claim 9.

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