Robotic arm follow-up control method, device, robotic arm and storage medium

Abstract

The present invention relates to the field of mechanical arm control, and discloses a mechanical arm follow-up control method, device, mechanical arm and storage medium. The method comprises: obtaining the motion parameters of the mechanical arm at the current moment, obtaining the actual position and reference position of the mechanical arm at the current moment according to the motion parameters, and calculating the tracking error of the mechanical arm at the current moment according to the actual position and the reference position; determining the same-sign monotonically decreasing boundary, absolute attraction layer boundary and steady-state error band boundary of the tracking error according to a preset control model; determining the control parameters of the control model according to the same-sign monotonically decreasing boundary, absolute attraction layer boundary and steady-state error band boundary, so as to control the tracking error within a preset range; calculating the torque output of the mechanical arm at the current moment according to the tracking error, and controlling the mechanical arm to move according to the torque output. By setting the control model of the tracking error, an appropriate torque output is obtained to achieve the effect of controlling the error.

Description

Technical Field

[0001] The present invention relates to the field of robot arm control, and in particular to a robot arm follow-up control method, device, robot arm and storage medium. Background Art

[0002] In the traditional position and posture adjustment and the adjustment process under the corresponding traditional control theory, if the robot wants to achieve the goal, using the traditional adjustment method, it may need to perform multiple stages of complex parameter adjustment control in different spaces and different postures. Different positions and postures are used for the same distance in the Cartesian joint space to convert the change of joint angle into a large difference. If a set of integral differential proportional values ​​is used, it is difficult to achieve the corresponding fast response effect. Some places will overshoot, and some places will respond slowly; if multi-stage parameter control is used, it is troublesome and difficult to select the appropriate parameters; under the traditional control logic, even if the system reaches a balanced state, the system will immediately lose the balanced state in the case of external disturbances, and the robustness is relatively poor. Summary of the invention

[0003] In a first aspect, the present application provides a robot arm follow-up control method, comprising:

[0004] Obtain motion parameters of the robot arm at the current moment, obtain the actual position and reference position of the robot arm at the current moment according to the motion parameters, and calculate the tracking error of the robot arm at the current moment according to the actual position and the reference position;

[0005] Determine the same-sign monotonically decreasing boundary, the absolute attraction layer boundary and the steady-state error band boundary of the tracking error according to a preset control model;

[0006] Determining the control parameters of the control model according to the monotonically decreasing boundary of the same sign, the boundary of the absolute attraction layer and the boundary of the steady-state error band, so as to control the tracking error within a preset range;

[0007] The torque output of the robot arm at the current moment is calculated according to the tracking error, and the robot arm is controlled to move according to the torque output.

[0008] Further, the control parameters include convergence parameters and tremor parameters;

[0009] The convergence parameter is used to control the convergence speed of the tracking error, and the tremor parameter is used to control the boundary value of the tracking error.

[0010] Further, the motion parameters include reference position data and actual position data of the robotic arm;

[0011] The calculation formula of the tracking error is as follows:

[0012] ek =r k -y k

[0013] In the formula, e k represents the tracking error at the current moment, r k represents the reference position data, y k Indicates the actual position data.

[0014] Furthermore, the expression of the control model is as follows:

[0015] e k+1 =(1-ρ)e k -εsgn(e k )

[0016] In the formula, e k represents the tracking error at the current moment, k as a subscript represents the current moment, ρ is the convergence parameter, ε is the tremor parameter, sgn(e k ) means e k The positive and negative cases, when e k When sgn(e k ) is 1, when e k When sgn(e k ) is -1.

[0017] Furthermore, the determining of the same-sign monotonically decreasing boundary, the absolute attraction layer boundary and the steady-state error band boundary of the tracking error according to the preset control model includes:

[0018] The calculation expression of the monotonically decreasing boundary of the same sign is:

[0019]

[0020] In the formula, Δ MDR is the monotonically decreasing boundary of the same sign, used to reflect the convergence process of the tracking error in the monotonic interval;

[0021] The calculation expression of the absolute attraction layer boundary is:

[0022]

[0023] In the formula, Δ AAL is the absolute attraction layer boundary, used to reflect the tracking error oscillation convergence process;

[0024] The expression of the steady-state error band boundary is:

[0025] When ρ=0, Δ SSE =ε.

[0026] When 0<ρ<2,

[0027] In the formula, Δ SSE is the steady-state error band boundary, which is used to measure the final convergence interval of the tracking error.

[0028] Furthermore, controlling the tracking error within a preset range includes:

[0029] By setting the control parameters, the preset range is located within the limited interval of the same-sign monotonically decreasing boundary, the absolute attraction layer boundary and the steady-state error band boundary, thereby controlling the tracking error to be within the preset range.

[0030] Furthermore, the torque output calculation expression is as follows:

[0031]

[0032] In the formula, e k represents the tracking error at the current moment, k as a subscript represents the current moment, ρ is the convergence parameter, ε is the tremor parameter, sgn(e k ) means e k The positive and negative cases, when e k When sgn(e k ) is 1, when e k When sgn(e k ) is -1, b1, b2, a1 and a2 represent system parameters, u represents the torque output, y represents the actual position coordinates of the robotic arm, and r represents the reference position coordinates of the robotic arm.

[0033] In a second aspect, the present application further provides a robot arm follow-up control device, comprising:

[0034] The error tracking module is used to obtain the motion parameters of the robot arm at the current moment, obtain the actual position and reference position of the robot arm at the current moment according to the motion parameters, and calculate the tracking error of the robot arm at the current moment according to the actual position and the reference position;

[0035] A boundary calculation module, used for determining the same-sign monotonically decreasing boundary, the absolute attraction layer boundary and the steady-state error band boundary of the tracking error according to a preset control model;

[0036] A parameter setting module, for determining the control parameters of the control model according to the same-sign monotonically decreasing boundary, the absolute attraction layer boundary and the steady-state error band boundary, so as to control the tracking error within a preset range;

[0037] A tracking control module is used to calculate the torque output of the robot arm at the current moment according to the tracking error, and control the robot arm to move according to the torque output. In a third aspect, the present application also provides a robot arm, including a processor and a memory, wherein the memory stores a computer program, and when the computer program runs on the processor, the robot arm tracking control method is executed.

[0038] In a fourth aspect, the present application also provides a readable storage medium storing a computer program, which executes the robot arm follow-up control method when running on a processor.

[0039] The present invention discloses a robot follow-up control method, device, robot and storage medium, the method comprising: obtaining the motion parameters of the robot at the current moment, calculating the tracking error of the robot at the current moment according to the motion parameters; determining the same-sign monotonically decreasing boundary, absolute attraction layer boundary and steady-state error band boundary of the tracking error according to a preset control model; determining the control parameters of the control model according to the same-sign monotonically decreasing boundary, absolute attraction layer boundary and steady-state error band boundary to control the tracking error within a preset range; calculating the torque output of the robot at the current moment according to the tracking error, and controlling the robot to move according to the torque output. By setting the control model of the tracking error, an appropriate torque output is obtained to achieve the effect of controlling the tracking error. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the technical solution of the present invention, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and should not be regarded as limiting the scope of protection of the present invention. In each of the drawings, similar components are numbered similarly.

[0041] Figure 1 A schematic diagram of a robot arm follow-up control method according to an embodiment of the present application is shown;

[0042] Figure 2 A schematic diagram of a simulation of a robot arm follow-up control method according to an embodiment of the present application is shown;

[0043] Figure 3 A simulation schematic diagram of another robot arm follow-up control method according to an embodiment of the present application is shown;

[0044] Figure 4 A schematic diagram of an interface of a robot arm follow-up control device according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0045] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0046] The components of the embodiments of the present invention generally described and shown in the drawings herein may be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed invention, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0047] Hereinafter, the terms "including", "having" and their cognates, which may be used in various embodiments of the present invention, are intended only to indicate specific features, numbers, steps, operations, elements, components or combinations of the foregoing items, and should not be understood as first excluding the existence of one or more other features, numbers, steps, operations, elements, components or combinations of the foregoing items or adding the possibility of one or more features, numbers, steps, operations, elements, components or combinations of the foregoing items.

[0048] Furthermore, the terms “first”, “second”, “third”, etc. are merely used for distinguishing descriptions and are not to be understood as indicating or implying relative importance.

[0049] Unless otherwise defined, all terms (including technical terms and scientific terms) used herein have the same meanings as those generally understood by those skilled in the art to which the various embodiments of the present invention belong. The terms (such as those defined in generally used dictionaries) will be interpreted as having the same meanings as the contextual meanings in the relevant technical field and will not be interpreted as having idealized meanings or overly formal meanings unless clearly defined in the various embodiments of the present invention.

[0050] The present application is applied to the follow-up control process of the robotic arm, and is used to control the movement of the robotic arm within a certain error range. Through a set error control model, the monotonically decreasing boundary of the same sign, the absolute attraction layer boundary and the steady-state error band boundary reflecting the convergence of the tracking error are calculated to determine the parameters in the error control model, thereby controlling the error convergence of the robotic arm during movement to be within a certain range, and during the movement process, ensuring that the error can converge quickly and stably.

[0051] The monotonically decreasing boundary of the same sign is used to reflect the above control model, and describes the way in which the tracking error converges in the monotonic interval, such as the speed and form of convergence. The larger the boundary value, the faster the convergence speed, and when the boundary value exists, the tracking error can converge to the convergence interval within a monotonic interval.

[0052] The absolute attraction layer boundary is used to reflect the above control model and the form of oscillation convergence of the tracking error in the convergence interval, such as oscillation frequency, speed, etc.

[0053] The boundary of the steady-state error band is used to reflect the control model and the range of the tracking error that finally converges. For example, if the boundary of the temperate error band is 2, it means that there will be a convergence interval of the tracking error in the interval [-2,2]. This convergence interval can be the same as the above interval or smaller.

[0054] Next, the technical solution of the present application is described with specific embodiments.

[0055] Example 1

[0056] like Figure 1 As shown, the robot arm follow-up control method of the present application includes the following steps:

[0057] Step S100, obtaining motion parameters of the robot arm at the current moment, obtaining the actual position and reference position of the robot arm at the current moment according to the motion parameters, and calculating the tracking error of the robot arm at the current moment according to the actual position and the reference position.

[0058] Specifically, the motion parameters include reference position data and actual position data. The reference position data is the position to which the robot moves according to the control command and the control personnel's requirements. The actual position data is the actual position of the robot after the robot executes the control command. These two position data can be directly obtained by measurement and will not be elaborated here.

[0059] When the robotic arm moves, there will be a tracking error, that is, there will be a position offset between the reference position to which the control command theoretically controls the robotic arm to move and the actual position to which the robotic arm actually moves due to external interference or system errors. The position offset here is the tracking error.

[0060] The tracking error can be calculated based on the reference position data and the actual position data, where the calculation formula of the tracking error is as follows:

[0061] e k =r k -y k

[0062] In the formula, e k represents the tracking error at the current moment, r k represents the reference position data, y k is the actual location data.

[0063] The time represented by k is determined according to the above data sampling cycle. For example, if the data is sampled once every 1 millisecond, the difference between time k and k+1 is 1 millisecond. It can be understood that the tracking error at the current moment is the error formed after the robot arm executes according to the torque output at the previous moment.

[0064] It can be understood that the parameters of the control model can be obtained through a PID (proportion integral derivative) control method.

[0065] Step S200, determining the same-sign monotonically decreasing boundary, the absolute attraction layer boundary and the steady-state error band boundary of the tracking error according to a preset control model.

[0066] The control model mentioned in this embodiment is a control model for controlling the tracking error to converge within a certain range. The control model is expressed as follows:

[0067] e k+1 =(1-ρ)e k -εsgn(e k )

[0068] In the formula, e k represents the tracking error at the current moment, e k+1 represents the tracking error at the next moment, ρ is the convergence parameter, ε is the tremor parameter, sgn(e k ) is used to obtain e k The positive and negative cases, when e k is greater than or equal to 0, then sgn(e k ) is 1, when e k is less than 0, then sgn(e k ) is -1.

[0069] This control model plans and controls the tracking error at the next moment k+1 based on the tracking error at the current moment k. The error is bound to exist due to the robot's motion environment and its own system. The normal operation of the robot arm can be guaranteed by controlling the tracking error within an acceptable range, so that the robot arm can achieve the expected effect.

[0070] From the above expression, we can see that when |e k When | is large, (1-ρ)e k plays a major role in compressing the tracking error by |1-ρ|; when |e k | is small, the second term εsgn(e k ) plays a major role in limiting the boundary of the tracking error. By adjusting ρ and ε, we can k| When it is large, it can ensure the dynamic quality of tracking error convergence and weaken |e k | When ρ is small, the high-frequency tremor of the signal is small. Therefore, by adjusting ρ, the convergence speed of the tracking error can be controlled. For example, the smaller ρ is, the faster the convergence speed is. Adjusting ε can control the oscillation boundary of the tracking error. The smaller ε is, the smaller the tremor of the entire robot system is. It can be understood that the above convergence parameters and tremor parameters need to be reasonably set according to the application environment to adapt to the robot.

[0071] The three boundaries of monotonically decreasing boundary with the same sign, absolute attraction layer boundary and steady-state error band boundary are evaluation parameters used to describe the control model's convergence status and convergence process of the tracking error. The settings of the above two parameters are determined based on these three boundaries.

[0072] The monotonically decreasing boundary with the same sign is used to reflect the convergence process of the tracking error in the monotonic interval. The current error is 100, and the convergence interval is [5, -5]. The monotonically decreasing boundary represents the form of convergence from 100 to the convergence interval. Its expression is obtained by the following derivation method:

[0073] Because tracking errors can be positive or negative, we will discuss them in different categories. k When >0, there exists:

[0074] Among them, when ρ is greater than 1, it means that the tracking error will cross the origin at every moment, and there is no monotonically decreasing or increasing interval in the process of change, so there is no convergence of monotonic intervals with the same sign.

[0075] Similarly, k <0 exists:

[0076]

[0077] Therefore, without considering disturbances, the monotonically decreasing boundary expression of the same sign is:

[0078]

[0079] In the formula, Δ MDR is the monotonically decreasing boundary of the same sign. The larger the boundary value is, the faster the convergence speed is.

[0080] The absolute attraction layer boundary is used to reflect the oscillation convergence of the tracking error, that is, to reflect the change of the tracking error in the convergence interval at each moment when the error value is already in the convergence interval. The derivation method is as follows:

[0081] When e k When >0, there exists:

[0082]

[0083] When e k When <0, there exists:

[0084]

[0085]

[0086]

[0087] In the formula, Δ AAL is the absolute attraction layer boundary. The larger its value is, the faster the tracking error converges within the convergence interval.

[0088] The steady-state error band boundary is used to measure the final convergence interval of the tracking error, or to measure the accuracy of the steady state. The final convergence interval is the maximum limit of the convergence range of the tracking error. For example, if the steady-state error band boundary is 0.5, it means that its maximum convergence interval is [-0.5, 0.5]. In actual work, the tracking error of the robot arm may converge in the interval [-0.1, 0.3].

[0089] Specifically, the steady-state error band boundary Δ SSE The expression of is derived as follows:

[0090] When ρ = 0, the tracking error converges to a point that crosses the origin, but the asymmetric interval {e k ,e k -εsgn(e k )}∈[-ε,ε], indicating that the asymmetric interval will not exceed the interval [-ε,ε].

[0091] Therefore, when ρ=0, there exists:

[0092] Δ SSE =ε

[0093] When 0<ρ<2, the following situation exists:

[0094] when When , it means that the tracking error is within the convergence boundary and the following relationship exists:

[0095]

[0096] when hour

[0097]

[0098] There is a tracking error e0, which is in the interval When the above rules are satisfied.

[0099] when hour

[0100] sgn(e k )=(-1) k sgn(e0),k≥1

[0101] e k+1 =(1-ρ)e k -(-1) k εsgn(e0)

[0102] By z-transform we can get

[0103]

[0104] Perform inverse z transform to get

[0105]

[0106] When 0<1-ρ<1, k→∞

[0107]

[0108] It can be obtained that when 0<ρ<2,

[0109] The values ​​of the above three boundaries can be used to judge the convergence of the control model to the tracking error, reflecting the convergence speed of the tracking error, the oscillation convergence mode and the final convergence interval. The requirements of the above three factors are different for different manipulators and different usage scenarios. Therefore, as long as the convergence parameters and tremor parameters that meet the above three requirements can be applied to the manipulator.

[0110] Step S300, determining the control parameters of the control model according to the monotonically decreasing boundary of the same sign, the absolute attraction layer boundary and the steady-state error band boundary, so as to control the tracking error within a preset range.

[0111] In step S200, the calculation methods of the three boundaries, namely the monotonically decreasing boundary, the absolute attraction layer boundary and the steady-state error band boundary, are determined. According to different robotic arms and different usage scenarios, the three boundaries can be designed separately so that the three boundaries are reasonable for the current usage environment of the robotic arm. Then, according to the above calculation formula, the corresponding convergence parameters and tremor parameters can be inferred.

[0112] It is understandable that there may be more than one parameter design that meets the above three boundary combinations, so the specific values ​​of the convergence parameter and the tremor parameter can be set by referring to their respective functions.

[0113] For example, take Δ MDR =0.75,Δ AAL=0.28125,Δ SSE =0.28125, then there is a setting method of ρ=0.4, ε=0.45. Under this setting method of motion parameters, the tracking error is converged in the interval of {-0.28125, 0.28125}.

[0114] In addition, there is a MDR =0.45,Δ AAL =0.225,Δ SSE =0.45, there is a setting of ρ=0, ε=0.45. Because ρ=0, the tracking error converges in an asymmetric interval, and the interval is in the interval [-0.45, 0.45]. Figure 2 As shown, under this setting, the system frequency f = 2Hz, the sampling time T s = 0.01s tracking error simulation diagram, it can be seen that the actual convergence interval [-0.15, 0.3] falls within the interval [-0.45, 0.45].

[0115] In addition, if the convergence speed is to be faster, the value of ρ can be increased to speed up the convergence speed. For example, on the basis of the above, if ρ = 1.2, there is Δ AAL =0.5625,Δ SSE =0.5625. Then the simulation diagram is as follows Figure 3 As shown, its convergence interval is [-0.5625, 0.5625], and because ρ>1, it will cross the origin at every moment, and the time it converges to the convergence interval is earlier than Figure 2 The time points shown in Figure 2 The convergence process of is relatively slow, while Figure 3 The convergence process is repeated a lot and the stability is low. It is understandable that because the convergence speed is accelerated, the overall stability is reduced, and the expansion of the convergence interval is one of the manifestations of the reduced stability.

[0116] Step S400: Calculate the torque output of the robotic arm at the current moment according to the tracking error, and control the robotic arm to move according to the torque output.

[0117] Since the motion of the robot arm is a discrete system, the discrete time system described by single input and single output considering the influence of external interference can be expressed as:

[0118] A(q -1 )y k =B(q -1 ) k

[0119] u k and kThey are the robot arm control torque output and actual output at time k, A(q -1 ) and B(q -1 ) is the delay operator q -1 Polynomial of:

[0120] A(q -1 )=1+a1q -1 +···+a n q -n

[0121] B(q -1 )=b1q -1 +···+b m q -m ,b≠0

[0122] where a1,...,a n ,b1,...,b m is the system parameter.

[0123] where y k It is known that, combined with the above control model, the torque output u can be calculated k , to ensure that the tracking error of the robot is within the range limited by the control model.

[0124] According to the parameters designed in step S300, the theoretical tracking error value at the next moment can be calculated based on the control model and the current tracking error, and then the torque output of the robot arm motor at the current moment can be calculated based on the tracking error at the next moment to keep the tracking error at the theoretical value.

[0125] Specifically, the expression for the torque output is as follows:

[0126]

[0127] Wherein, b1, b2, a1 and a2 represent system parameters, k as a subscript represents the time, u represents the torque input of the motor, and y represents the target position coordinate of the robotic arm.

[0128] The system parameters are parameters set according to the robot system itself. According to the above expression, the torque output of the motor at the current moment should be obtained. It can be understood that the torque output at the current moment is used to make the robot move to the reference position at the next moment. The error between the actual position it moves to and the reference position meets the tracking error calculated above, so that the tracking error is within the range controlled by the control model. According to Figure 2 and Figure 3It can be seen from the simulation image in that the robot arm controls the tracking error according to the above control model, so that the error of the robot arm can be stably converged within a range, and by setting the corresponding control parameters, the tracking error of the robot arm can operate stably within the convergence range.

[0129] This embodiment sets up a control model to limit the convergence of the tracking error, so that the tracking error can be controlled according to the needs of the operator, thereby obtaining an appropriate torque output to control the tracking error caused by the robot arm in actual movement to converge within an acceptable range, and can also control the convergence speed and convergence form of the error, thereby ensuring the steady state of the robot arm during movement as much as possible and ensuring the working efficiency of the robot arm.

[0130] Example 2

[0131] like Figure 4 As shown, the present application also provides a robot arm follow-up control device, comprising:

[0132] The error tracking module 10 is used to obtain the motion parameters of the robot arm at the current moment, obtain the actual position and reference position of the robot arm at the current moment according to the motion parameters, and calculate the tracking error of the robot arm at the current moment according to the actual position and the reference position;

[0133] Boundary calculation module 20, used to determine the same-sign monotonically decreasing boundary of the tracking error, the absolute attraction layer boundary and the steady-state error band boundary by a preset control model;

[0134] A parameter setting module 30, for determining the control parameters of the control model according to the same-sign monotonically decreasing boundary, the absolute attraction layer boundary and the steady-state error band boundary, so as to control the tracking error within a preset range;

[0135] The tracking control module 40 is used to calculate the torque output of the robotic arm at a current moment according to the tracking error, and control the robotic arm to move according to the torque output.

[0136] The present application also provides a robotic arm, comprising a processor and a memory, wherein the memory stores a computer program, and when the computer program runs on the processor, the robotic arm follow-up control method is executed.

[0137] The present application also provides a readable storage medium storing a computer program, wherein the computer program executes the robot arm follow-up control method when running on a processor.

[0138] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can also be implemented in other ways. The device embodiments described above are merely schematic. For example, the flowcharts and structure diagrams in the accompanying drawings show the possible architecture, functions and operations of the devices, methods and computer program products according to multiple embodiments of the present invention. In this regard, each box in the flowchart or block diagram can represent a module, a program segment or a part of a code, and the module, a program segment or a part of a code contains one or more executable instructions for implementing the specified logical function. It should also be noted that in an alternative implementation, the functions marked in the box can also occur in a different order from the order marked in the accompanying drawings. For example, two consecutive boxes can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the structure diagram and / or the flow chart, and the combination of boxes in the structure diagram and / or the flow chart, can be implemented with a dedicated hardware-based system that performs a specified function or action, or can be implemented with a combination of dedicated hardware and computer instructions.

[0139] In addition, the functional modules or units in the various embodiments of the present invention may be integrated together to form an independent part, or each module may exist independently, or two or more modules may be integrated to form an independent part.

[0140] If the functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a smart phone, a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0141] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A robot arm follow-up control method, characterized in that: include: Obtain motion parameters of the robotic arm at the current moment, obtain the actual position and reference position of the robotic arm at the current moment according to the motion parameters, and calculate the tracking error of the robotic arm at the current moment according to the actual position and the reference position; Determine the same-sign monotonically decreasing boundary, the absolute attraction layer boundary and the steady-state error band boundary of the tracking error according to a preset control model; Determining the control parameters of the control model according to the monotonically decreasing boundary of the same sign, the boundary of the absolute attraction layer and the boundary of the steady-state error band, so as to control the tracking error within a preset range; Calculating the torque output of the robotic arm at a current moment according to the tracking error, and controlling the robotic arm to move according to the torque output; The control parameters include convergence parameters and tremor parameters; The convergence parameter is used to control the convergence speed of the tracking error, and the tremor parameter is used to control the boundary value of the tracking error; The expression of the control model is as follows: And k+1 =(1-ρ)e k -εsgn(e k ); In the formula, e k represents the tracking error at the current moment, k as a subscript represents the current moment, ρ is the convergence parameter, ε is the tremor parameter, sgn(e k ) means e k The positive and negative cases, when e k When sgn(e k ) is 1, when e k When sgn(e k ) is -1; The step of determining the same-sign monotonically decreasing boundary, the absolute attraction layer boundary and the steady-state error band boundary of the tracking error according to the preset control model includes: The calculation expression of the monotonically decreasing boundary of the same sign is: In the formula, Δ MDR is the monotonically decreasing boundary of the same sign, used to reflect the convergence process of the tracking error in the monotonic interval; The calculation expression of the absolute attraction layer boundary is: In the formula, Δ AAL is the absolute attraction layer boundary, used to reflect the tracking error oscillation convergence process; The expression of the steady-state error band boundary is: When ρ = 0, Δ SSE = ε When 0<ρ<2, In the formula, Δ SSE is the steady-state error band boundary, used to measure the final convergence interval of the tracking error; The calculation expression of the torque output is as follows: In the formula, e k represents the tracking error at the current moment, k as a subscript represents the current moment, ρ is the convergence parameter, ε is the tremor parameter, sgn(e k ) means e k The positive and negative cases, when e k When sgn(e k ) is 1, when ek is less than 0, then sgn(e k ) is -1, b1, b2, a1 and a2 represent system parameters, u represents the torque output, y represents the actual position coordinates of the robotic arm, and r represents the reference position coordinates of the robotic arm.

2. The robot arm follow-up control method according to claim 1, characterized in that: The motion parameters include reference position data and actual position data of the robotic arm; The calculation formula of the tracking error is as follows: e k =r k -y k In the formula, e k represents the tracking error at the current moment, r k represents the reference position data, y k Indicates the actual position data.

3. The robot arm follow-up control method according to claim 1, characterized in that: The step of controlling the tracking error within a preset range includes: By setting the control parameters, the preset range is located within the limited interval of the same-sign monotonically decreasing boundary, the absolute attraction layer boundary and the steady-state error band boundary, thereby controlling the tracking error to be within the preset range.

4. A robot arm follow-up control device, used to execute the robot arm follow-up control method according to any one of claims 1 to 3, characterized in that: include: The error tracking module is used to obtain the motion parameters of the robot arm at the current moment, obtain the actual position and reference position of the robot arm at the current moment according to the motion parameters, and calculate the tracking error of the robot arm at the current moment according to the actual position and the reference position; A boundary calculation module, used for determining the same-sign monotonically decreasing boundary, the absolute attraction layer boundary and the steady-state error band boundary of the tracking error according to a preset control model; A parameter setting module, for determining the control parameters of the control model according to the same-sign monotonically decreasing boundary, the absolute attraction layer boundary and the steady-state error band boundary, so as to control the tracking error within a preset range; The tracking control module is used to calculate the torque output of the mechanical arm at a current moment according to the tracking error, and control the mechanical arm to move according to the torque output.

5. A robotic arm, characterized in that: The method comprises a processor and a memory, wherein the memory stores a computer program, and when the computer program is run on the processor, the robot arm follow-up control method according to any one of claims 1 to 3 is executed.

6. A readable storage medium, characterized in that: The device stores a computer program, which executes the robot arm follow-up control method according to any one of claims 1 to 3 when running on a processor.

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