Control method, device and equipment of three-rope parallel robot and storage medium

Abstract

Embodiments of the present application provide a kind of control method, device, equipment and storage medium of three rope parallel robot, it is related to parallel robot technical field.The control method contains steps S1 to step S8. S1, the desired trajectory sent by host computer is acquired.S2, according to the desired trajectory, the desired position of end effector is acquired, and the desired torque of drive motor is acquired.S3, according to the desired torque of drive motor, the operation of motor is controlled.S4, the actual torque and actual speed of drive motor output by motor encoder are acquired.S5, according to the actual torque and desired torque of drive motor, proportional integral closed-loop compensation control is carried out to drive motor.S6, according to the actual speed of drive motor, the theoretical rope length is acquired by integration.S7, according to the theoretical rope length, with desired position as iteration initial value, the actual position of end effector is acquired by Newton iteration method.S8, according to actual position and desired position, proportional differential closed-loop compensation control is carried out to desired trajectory.

Description

Technical Field

[0001] This invention relates to the field of parallel robot technology, and more specifically, to a control method, apparatus, device, and storage medium for a three-rope parallel robot. Background Technology

[0002] With the continuous advancement of industrial technology, heavy-duty material handling robots have developed rapidly. They are used in the automotive, electronics, rubber and plastics, shipbuilding, metal products, and food industries, primarily performing tasks such as sorting, handling, casting, and palletizing. Traditional industrial robots suffer from drawbacks such as high inertia, inflexibility, and low ease of use. Future heavy-duty material handling robots will develop towards intelligent integration, lightweight design, and virtual commissioning.

[0003] Based on their structure, robots are mainly divided into serial and parallel robots; based on their materials, robots are further divided into flexible robots and rigid robots. Compared with these robots, rope-driven parallel robots combine the advantages of parallel robots, such as high rigidity, high precision, and strong load capacity, with the advantages of flexible robots, such as light weight, fixed drive source, and low inertia.

[0004] Due to the inherent flexibility of rope robots, rope-driven parallel robots have specific requirements for self-calibration methods. Calibration is a necessary means to improve robot accuracy. Traditional calibration methods require high-precision external measuring equipment and complex calibration procedures. The time-consuming, cumbersome, and costly calibration methods of traditional control methods greatly limit the ability of rope-driven parallel robots to achieve rapid disassembly, assembly, and reconfiguration.

[0005] In view of this, the applicant hereby submits this application after studying the existing technology. Summary of the Invention

[0006] The present invention provides a control method, apparatus, device and storage medium for a three-rope parallel robot to improve at least one of the above-mentioned technical problems.

[0007] First aspect

[0008] This invention provides a control method for a three-rope parallel robot, comprising steps S1 to S8.

[0009] S1. Obtain the desired trajectory sent by the host computer.

[0010] S2. Based on the desired trajectory, obtain the desired position of the end effector and the desired torque of the drive motor.

[0011] S3. Control the motor operation according to the desired torque of the drive motor.

[0012] S4. Obtain the actual torque and actual speed of the drive motor output by the motor encoder.

[0013] S5. Perform proportional-integral closed-loop compensation control on the drive motor based on the actual torque and the desired torque of the drive motor.

[0014] S6. Integrate based on the actual speed of the drive motor to obtain the theoretical rope length.

[0015] S7. Based on the theoretical rope length, using the desired position as the initial value for iteration, obtain the actual position of the end effector through Newton's iteration method.

[0016] S8. Based on the actual position and the desired position, perform proportional-derivative closed-loop compensation control on the desired trajectory.

[0017] The second aspect

[0018] This invention provides a control device for a three-rope parallel robot, comprising:

[0019] The desired trajectory acquisition module is used to acquire the desired trajectory sent by the host computer.

[0020] The initial parameter acquisition module is used to obtain the desired position of the end effector and the desired torque of the drive motor based on the desired trajectory.

[0021] The drive module is used to control the operation of the motor according to the desired torque of the drive motor.

[0022] The actual parameter acquisition module is used to acquire the actual torque and actual speed of the drive motor output by the motor encoder.

[0023] The torque compensation module is used to perform proportional-integral closed-loop compensation control on the drive motor based on the actual torque and the desired torque of the drive motor.

[0024] The theoretical rope length acquisition module is used to integrate based on the actual speed of the drive motor to obtain the theoretical rope length.

[0025] The actual position acquisition module is used to obtain the actual position of the end effector by using the theoretical rope length and the expected position as the initial value for iteration through Newton's iteration method.

[0026] The position compensation module is used for closed-loop compensation control of the desired trajectory by proportional-derivative calculation based on the actual position and the desired position.

[0027] Third aspect

[0028] This invention provides a control device for a three-rope parallel robot, comprising a processor, a memory, and a computer program stored in the memory. The computer program can be executed by the processor to implement the control method for the three-rope parallel robot as described in any paragraph of the first aspect.

[0029] Fourth aspect

[0030] This invention provides a computer-readable storage medium. The computer-readable storage medium includes a stored computer program, wherein, when the computer program is executed, it controls the device containing the computer-readable storage medium to perform the control method for a three-rope parallel robot as described in any paragraph of the first aspect.

[0031] By adopting the above technical solution, the present invention can achieve the following technical effects:

[0032] This invention employs both trajectory tracking control and force tracking control for simultaneous motion control of the robot, achieving relatively precise motion control through force-position hybrid control. This effectively improves the robot's adaptability to external factors such as wind and pulley friction, while also considering both acceleration and continuity of motion. This satisfies the requirements for rapid response, continuous end-effector trajectory, and compliant interaction with external forces in trajectory planning and control of the end-effector load of a rope-driven robot. Attached Figure Description

[0033] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0034] Figure 1 This is a flowchart illustrating the control method.

[0035] Figure 2 This is an isometric drawing of a three-rope parallel robot.

[0036] Figure 3 This is a schematic diagram of the circuit connection of a three-rope parallel robot.

[0037] Figure 4 This is a schematic diagram of the control method.

[0038] Figure 5 This is a schematic diagram of the control device.

[0039] The markings in the diagram are: 1-fixed base, 2-column, 3-turntable bearing, 4-pulley, 5-winner, 6-beam, 7-end actuator. Detailed Implementation

[0040] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0041] Example 1

[0042] Please see Figures 1 to 4 The first embodiment of the present invention provides a control method for a three-rope parallel robot, which can be executed by a control device for the three-rope parallel robot (hereinafter referred to as: control device). In particular, it is executed by one or more processors in the control device to implement steps S1 to S8.

[0043] S1. Obtain the desired trajectory sent by the host computer.

[0044] like Figure 2 and Figure 3 As shown, the three-rope parallel robot includes three sets of identical rope structures and an end effector 7 connected to the three sets of rope structures. Each rope structure includes a fixed base 1, a column 2 vertically mounted on the fixed base, a turntable bearing 3 mounted on the top of the column 2, a pulley 4 mounted on the turntable bearing, a crossbeam 6 connecting two sets of rope structures, a winch 5 mounted on the fixed base, a drive motor connected to the winch 5, and ropes that connect to the end effector 7 and the winch 5 at both ends via pulleys.

[0045] The drive motor drives the winch 5 to rotate, causing the rope to lengthen or shorten, thereby changing the position of the end effector 7. The end effector 7 is used to lift the load. For details regarding the specific structure of the three-rope parallel robot, please refer to the applicant's patent application with application number "202210570198.1" and invention title "Energy-Recovering Rope Robot and Its Control Method, Device, and Storage Medium," which will not be elaborated upon here.

[0046] It is understood that in this embodiment, the control device is a motion controller. It is capable of receiving control trajectories sent by a host computer. In other embodiments, the control device may be an electronic device with computing power, such as a portable laptop computer, desktop computer, server, smartphone, or tablet computer.

[0047] Specifically, the desired trajectory P of the end effector is directly set in the host computer. Where P = f(t).

[0048] First, a time signal t is given. Then, the desired trajectory with time at the end position is set.

[0049]

[0050] S2. Based on the desired trajectory, obtain the desired position of the end effector and the desired torque of the drive motor.

[0051] Specifically, the desired position can be obtained directly from the desired trajectory. The desired torque, however, needs to be obtained by inverse kinematics of the desired trajectory.

[0052] Given the pose of the end effector at each moment and the coordinates of the fixed pulley center point, the real-time desired rope length of the robot can be obtained through geometric relationships. Using the desired trajectory controlled based on the coordinate position of the end effector load of the rope robot, the rope length of the robot can be calculated using inverse kinematics.

[0053] Based on the above embodiments, in an optional embodiment of the present invention, step S2 specifically includes steps S21 to S23.

[0054] S21. Obtain the desired position of the end effector based on the desired trajectory.

[0055] Specifically, the coordinates of the end effector at various moments can be obtained based on the desired trajectory. That is, the real-time position coordinates at the current time.

[0056] S22. Obtain the pulley center coordinates, and based on the pulley center coordinates and the desired trajectory, obtain the desired lengths of the three ropes. Specifically, the desired rope length is the rope length obtained through real-time desired trajectory tracking control. The calculation model for the desired length of the three ropes is as follows:

[0057]

[0058] In the formula, l i = [l1, l2, l3] is a column vector composed of the lengths of the three ropes, A i Let P be the coordinates of the center of the i-th pulley, P be the coordinates of the end effector, and T be the transpose.

[0059] S23. Based on the desired lengths of the three ropes, obtain the desired torque of the drive motor using the dynamic model of the rope robot. The dynamic model is as follows:

[0060]

[0061] In the formula, τ=[τ1τ2τ3] is the torque of the motor driver, J mLet r be the equivalent inertia of the actuator, r be the radius of the winch, J be the Jacobian matrix obtained by differentiating the X, Y, and Z trajectories planned by the end effector with respect to the lengths of the three ropes respectively, l = [l1, l2, l3] be the column vector composed of the lengths of the three ropes, I be the identity matrix, and B be the equivalent inertia of the actuator. m Let M be the equivalent damping coefficient matrix of the actuator, M be the mass matrix of the moving platform, and G be the dynamic vector of the moving platform.

[0062] Specifically, the rope length, l, is obtained through position planning based on the position coordinates of the end effector. i The rope velocity is obtained by differentiating with respect to time: In the formula, Let be the velocity of the rope. Then, differentiating the rope velocity with respect to time gives the rope acceleration: In the formula, Acceleration of the rope

[0063] The moving platform is modeled using the Lagrangian method based on the rope velocity and acceleration. Then, by utilizing the relationship between the pulley and the rope length, differential flatness is used to express the torque of the motor actuator using the rope length, rope velocity, and acceleration information, thus forming the dynamic model. This process transforms the nonlinear system into a linear system, thereby establishing the dynamic model of the entire rope robot. The motor torque is directly obtained from the first and second derivatives of the rope length, reducing the computational load and shortening the computation time.

[0064] S3. Control the motor operation according to the desired torque of the drive motor.

[0065] Based on the above embodiments, in an optional embodiment of the present invention, step S3 specifically includes steps S31 to S32.

[0066] S31. Obtain the motor control signal based on the relationship between the motor torque and the drive signal.

[0067] S32. Control the operation of the rope drive motor according to the motor control signal.

[0068] Specifically, the relationship between the motor's output and the control signal can be obtained from the motor's instruction manual: 1V = aN·m. Based on the previously calculated desired torque, the control signal for the motor is then derived to control its operation.

[0069] S4. Obtain the actual torque and actual speed of the drive motor output by the motor encoder.

[0070] Specifically, the encoder can directly obtain the motor's output information, including the actual torque and actual speed.

[0071] S5. Perform proportional-integral closed-loop compensation control on the drive motor based on the actual torque and the desired torque of the drive motor.

[0072] Specifically, proportional-integral (PI) control is used to address the error between the actual and desired motor torque, thus forming a closed-loop force control. Parameter adjustments are made using PI control, and the resulting adjustment compensates the actual motor torque feedback, thus completing the closed-loop force control. The error between the actual and desired torque is then fed back to the motor torque to be executed via PI control. Wherein:

[0073] Motor torque error is defined as: e D =τ-τ 实 In the formula, τ is the desired motor torque, τ 实 Actual motor torque.

[0074] Define the compensation end position derived from proportional-integral control as e. 1D The proportional-integral closed-loop compensation control model for the torque of the drive motor is as follows:

[0075]

[0076] In the formula, e 1D For torque compensation, k p1I For the proportional parameter, e D The error between the actual torque and the desired torque, For integration parameters.

[0077] S6. Integrate based on the actual speed of the drive motor to obtain the theoretical rope length.

[0078] Based on the above embodiments, in an optional embodiment of the present invention, step S6 specifically includes steps S61 to S62.

[0079] S61. Obtain the rope speed based on the actual rotational speed of the drive motor. The calculation model for the rope speed is as follows: In the formula, Let v be the actual rope speed of the i-th rope. i卷 Let r be the drum rotation speed corresponding to the i-th rope, and r be the drum radius. 绳 Let be the radius of the rope.

[0080] S62. Integrate based on the rope velocity to obtain the theoretical rope length. The calculation model for the theoretical rope length is as follows: l i =∫v i dt, where v i The speed is the speed of the rope.

[0081] Specifically, the actual motor speed is obtained through an encoder. Then, the rope speed is determined using the known drum diameter of the winch, the number of rope turns, and the rope diameter. Finally, the actual rope length l is obtained by integrating the rope velocity over time. i .

[0082] S7. Based on the theoretical rope length, using the desired position as the initial value for iteration, obtain the actual position of the end effector through Newton's iteration method.

[0083] Specifically, the actual rope length obtained from the conversion is transformed into the end effector trajectory position using forward kinematics. The conversion process is as follows. Forward kinematics involves solving for the pose of the end effector given the rope length.

[0084] Based on the above embodiments, in an optional embodiment of the present invention, the end-effector pose is obtained using the Newton-Raphson iteration method. By using the Newton-Raphson iteration method, the desired trajectory is used as the initial value for iteration to determine the actual pose of the end-effector. The calculation model of the Newton-Raphson iteration method is as follows:

[0085] f i (P)=(A i -P) T (A i -P)-l i 2

[0086] In the formula, f i (P) represents the squared difference between the expected rope length and the actual rope length, and A i Let P be the center coordinates of the pulley corresponding to the i-th rope, P be the desired position of the end effector, T denote transpose, and l i = [l1, l2, l3] is a column vector consisting of the theoretical rope lengths of the three ropes.

[0087] Specifically, f i (P) Performing a first-order Taylor expansion, we obtain the following expression:

[0088]

[0089] f i (P0+ΔP)-f i (P0)=JΔP

[0090] f i (P0+ΔP)-f i (P0)=ΔP k →f(P k )=JΔP k →ΔP k =-J + f(P k )

[0091] In the formula, P is the coordinate position of the desired trajectory in step S01, and P0+ΔP is along f i (P) approaches P0, therefore ΔP approaches 0, A i Let f be the coordinates of the center point of the pulley corresponding to the i-th rope. i (P) represents the squared difference between the expected rope length and the actual rope length, f i (P0) is f i (P) is the first derivative of P0+ΔP. Let be the kinematic Jacobian matrix of the system. f i (P0+ΔP) is the first-order Taylor remainder term in P0+ΔP, P k Let ΔP be the coordinates of the terminal trajectory obtained in the k-th iteration. k =JΔP, i.e., P k+1 The first-order Taylor remainder term of the terminal trajectory coordinates obtained after the (k+1)th iteration, J + Let J be the Moore-Penrose generalized inverse, and ε be the iteration precision.

[0092] Let P k+1 =P k +ΔP k The position ΔP of the final correct solution is obtained when maxΔP≤ε. k .

[0093] Based on existing force-position hybrid control technology, this patent uses Newton's iteration method to calculate the position of the end effector according to the rope length. However, since it is difficult to determine the initial value of the iteration when Newton's iteration method is iterating, this algorithm uses the expected trajectory as the initial value of the iteration to solve for the end position. Compared with traditional vision controllers, this method determines the pose feedback of the end effector faster.

[0094] S8. Based on the actual position and the desired position, perform proportional-derivative closed-loop compensation control on the desired trajectory.

[0095] Specifically, because position control requires a high response speed, the actual position coordinates of the end effector calculated in step S7 are fed back into the control loop. The error between these two coordinates and the coordinates of the desired trajectory at that moment is adjusted using a proportional-derivative control method. After adjustment, compensation is applied to the actual position fed back to form a new execution trajectory, thereby achieving closed-loop position control.

[0096] Define the end-effector pose error as: e I =PP 实 In the formula, P is the desired position, P 实 This refers to the actual location.

[0097] Define the compensated end-effector pose obtained by the proportional-derivative control method as e. 1I The closed-loop compensation control model for the proportional-derivative of the desired trajectory is as follows:

[0098]

[0099] In the formula, e 1I For position compensation, k p2I For the proportional parameter, e I The error between the actual position and the expected position, T d For integration parameters.

[0100] Compared to semi-closed-loop position control based on motor speed, closed-loop compensation control that performs proportional-derivative analysis on the desired trajectory can feed back a portion or all of the control system output to the system input through certain methods and devices. The feedback information is then compared with the original input information, and the comparison result is applied to the system for control, preventing the system from deviating from the predetermined target. Compared to semi-closed-loop control, full closed-loop control reduces mechanical error to some extent by converting the end-effector trajectory into an analog input to the motor, which involves a certain mechanical error. This is because the motor speed is then converted back into the end-effector position as feedback, which reduces mechanical error compared to directly using the motor speed as feedback.

[0101] The control method for the three-rope parallel robot in this invention uses both position tracking control and force tracking control to control the robot's motion. Through force-position hybrid control, it achieves relatively precise motion control of the robot.

[0102] This invention employs both trajectory tracking control and force tracking control for simultaneous motion control of the robot, achieving relatively precise motion control through force-position hybrid control. This effectively improves the robot's adaptability to external factors such as wind and pulley friction, while also considering both acceleration and continuity of motion. This satisfies the requirements for rapid response, continuous end-effector trajectory, and compliant interaction with external forces in trajectory planning and control of the end-effector load of a rope-driven robot.

[0103] Example 2

[0104] like Figure 5 As shown, an embodiment of the present invention provides a control device for a three-rope parallel robot, which includes:

[0105] The desired trajectory acquisition module 100 is used to acquire the desired trajectory sent by the host computer.

[0106] The initial parameter acquisition module 200 is used to acquire the desired position of the end effector and the desired torque of the drive motor based on the desired trajectory.

[0107] The drive module 300 is used to control the operation of the motor according to the desired torque of the drive motor.

[0108] The actual parameter acquisition module 400 is used to acquire the actual torque and actual speed of the drive motor output by the motor encoder.

[0109] The torque compensation module 500 is used to perform proportional-integral closed-loop compensation control on the drive motor based on the actual torque and the desired torque of the drive motor.

[0110] The theoretical rope length acquisition module 600 is used to integrate based on the actual speed of the drive motor to obtain the theoretical rope length.

[0111] The actual position acquisition module 700 is used to obtain the actual position of the end effector by using the theoretical rope length and the expected position as the initial value for iteration through Newton's iteration method.

[0112] The position compensation module 800 is used for closed-loop compensation control of the desired trajectory by proportional-derivative calculation based on the actual position and the desired position.

[0113] Based on the above embodiments, in an optional embodiment of the present invention, the initial parameter acquisition module 200 specifically includes:

[0114] The desired position acquisition unit is used to acquire the desired position of the end effector based on the desired trajectory.

[0115] The expected length acquisition unit is used to obtain the center coordinates of the pulley and, based on these coordinates and the desired trajectory, to obtain the expected lengths of the three ropes. The calculation model for the expected lengths of the three ropes is as follows: In the formula, l i = [l1, l2, l3] is a column vector composed of the lengths of the three ropes, A i Let P be the coordinates of the center of the i-th pulley, P be the coordinates of the end effector, and T be the transpose.

[0116] The desired torque acquisition unit is used to obtain the desired torque of the drive motor based on the desired lengths of the three ropes and the dynamic model of the rope robot. The dynamic model is as follows:

[0117]

[0118] In the formula, τ=[τ1τ2τ3] is the torque of the motor driver, J m Let r be the equivalent inertia of the actuator, r be the radius of the winch, J be the Jacobian matrix obtained by differentiating the X, Y, and Z trajectories planned by the end effector with respect to the lengths of the three ropes respectively, l = [l1, l2, l3] be the column vector composed of the lengths of the three ropes, I be the identity matrix, and B be the equivalent inertia of the actuator. mLet M be the equivalent damping coefficient matrix of the actuator, M be the mass matrix of the moving platform, and G be the dynamic vector of the moving platform.

[0119] Based on the above embodiments, in an optional embodiment of the present invention, the driving module 300 specifically includes:

[0120] The motor control signal acquisition unit is used to acquire the motor control signal based on the relationship between the motor torque and the drive signal.

[0121] The motor drive unit is used to control the operation of the drive motor of the rope according to the motor control signal.

[0122] Based on the above embodiments, in an optional embodiment of the present invention, the proportional-integral closed-loop compensation control model for the torque of the drive motor is as follows: In the formula, e 1D For torque compensation, k p1I For the proportional parameter, e D The error between the actual torque and the desired torque, For integration parameters.

[0123] Based on the above embodiments, in an optional embodiment of the present invention, the theoretical rope length acquisition module 600 specifically includes:

[0124] The rope speed acquisition unit is used to obtain the rope speed based on the actual rotational speed of the drive motor. The calculation model for the rope speed is as follows: In the formula, Let v be the actual rope speed of the i-th rope. i卷 Let r be the drum rotation speed corresponding to the i-th rope, and r be the drum radius. 绳 Let be the radius of the rope.

[0125] The theoretical rope length acquisition unit is used to obtain the theoretical rope length by integrating the rope velocity. The calculation model for the theoretical rope length is as follows: l i =∫v i dt, where v i The speed is the speed of the rope.

[0126] Based on the above embodiments, in an optional embodiment of the present invention, the computational model of Newton's iteration method is: f i (P)=(A i -P) T (A i -P)-l i 2 In the formula, f i (P) represents the squared difference between the expected rope length and the actual rope length, and A iLet P be the center coordinates of the pulley corresponding to the i-th rope, P be the desired position of the end effector, T denote transpose, and l i = [l1, l2, l3] is a column vector consisting of the theoretical rope lengths of the three ropes.

[0127] Based on the above embodiments, in an optional embodiment of the present invention, the closed-loop compensation control model for the proportional derivative of the desired trajectory is as follows: In the formula, e 1I For position compensation, k p2I For the proportional parameter, e I The error between the actual position and the expected position, T d For integration parameters.

[0128] Example 3

[0129] This invention provides a control device for a three-rope parallel robot, comprising a processor, a memory, and a computer program stored in the memory. The computer program can be executed by the processor to implement the control method for the three-rope parallel robot as described in any paragraph of Embodiment 1.

[0130] Example 4

[0131] This invention provides a computer-readable storage medium. The computer-readable storage medium includes a stored computer program, wherein, when the computer program is executed, it controls the device containing the computer-readable storage medium to perform the control method for a three-rope parallel robot as described in any paragraph of Embodiment 1.

[0132] In the several embodiments provided in this invention, it should be understood that the disclosed apparatus and methods can also be implemented in other ways. The apparatus and method embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0133] In addition, the functional modules in the various embodiments of the present invention can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0134] If the aforementioned functions are implemented as software functional 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 a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, electronic device, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks. It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. In the absence of further restrictions, an element defined by the phrase "comprising a..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0135] The terminology used in the embodiments of this invention is for the purpose of describing particular embodiments only and is not intended to limit the invention. The singular forms “a,” “the,” and “the” as used in the embodiments of this invention and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0136] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0137] Depending on the context, the word "if" as used here can be interpreted as "when," "when," "in response to determination," or "in response to detection." Similarly, depending on the context, the phrase "if determination" or "if detection (of the stated condition or event)" can be interpreted as "when determination," "in response to determination," "when detection (of the stated condition or event)," or "in response to detection (of the stated condition or event)."

[0138] The use of "first" and "second" in the embodiments is merely to distinguish similar objects and does not represent a specific ordering of objects. It is understood that "first" and "second" can be interchanged in a specific order or sequence where permitted. It should be understood that the objects distinguished by "first" and "second" can be interchanged where appropriate so that the embodiments described herein can be implemented in an order other than those illustrated or described herein.

[0139] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A control method for a three-rope parallel robot, characterized in that, Include: Obtain the desired trajectory sent by the host computer; Based on the desired trajectory, the desired position of the end effector and the desired torque of the drive motor are obtained; Control the motor operation according to the desired torque of the drive motor; Obtain the actual torque and actual speed of the drive motor output by the motor encoder; Based on the actual torque and desired torque of the drive motor, a proportional-integral closed-loop compensation control is performed on the drive motor. The theoretical rope length is obtained by integrating the actual rotational speed of the drive motor. Based on the theoretical rope length, and using the desired position as the initial value for iteration, the actual position of the end effector is obtained through Newton's iteration method. Based on the actual position and the desired position, a closed-loop compensation control with proportional-derivative functions is performed on the desired trajectory. Based on the desired trajectory, the desired position of the end effector and the desired torque of the drive motor are obtained, specifically including: Based on the desired trajectory, the desired position of the end effector is obtained; Obtain the center coordinates of the pulley, and based on the pulley center coordinates and the desired trajectory, obtain the desired lengths of the three ropes; wherein, the calculation model for the desired lengths of the three ropes is: In the formula, The column vector consisting of the lengths of the three ropes. For the first The center coordinates of each pulley For end effector coordinates, For transpose; Based on the desired lengths of the three ropes, the desired torque of the drive motor is obtained using the dynamic model of the rope robot; wherein, the dynamic model is: In the formula, For the torque of the motor driver, For the equivalent inertia of the driver, For winch radius, The Jacobian matrix is ​​obtained by differentiating the X, Y, and Z trajectories planned by the end effector with respect to the lengths of the three ropes respectively. The column vector consisting of the lengths of the three ropes. For identity matrix, The equivalent damping coefficient matrix of the driver, For the mass matrix of the dynamic platform, The dynamic vector of the moving platform.

2. The control method for a three-rope parallel robot according to claim 1, characterized in that, The proportional-integral closed-loop compensation control model for the torque of the drive motor is as follows: In the formula, For torque compensation, For proportional parameters, The error between the actual torque and the desired torque, For integration parameters.

3. The control method for a three-rope parallel robot according to claim 1, characterized in that, The theoretical rope length is obtained by integrating the expected lengths of the three ropes and the actual rotational speed of the drive motor, specifically including: The rope speed is obtained based on the actual rotational speed of the drive motor; wherein the calculation model for the rope speed is: In the formula, For the first The actual speed of the rope, For the first The drum speed corresponding to each rope For the drum radius, Let be the radius of the rope; The theoretical rope length is obtained by integrating the rope velocity; the calculation model for the theoretical rope length is as follows: In the formula, The speed is the speed of the rope.

4. The control method for a three-rope parallel robot according to claim 1, characterized in that, The computational model of the Newton iteration method is as follows: In the formula, The square difference between the expected rope length and the actual rope length. For the first The coordinates of the pulley center point corresponding to the rope For the desired position of the end effector, Indicates transpose, Let be a column vector consisting of the theoretical lengths of the three ropes.

5. The control method for a three-rope parallel robot according to claim 1, characterized in that, The closed-loop compensation control model for the proportional derivative of the desired trajectory is as follows: In the formula, For location compensation, For proportional parameters, The error between the actual position and the desired position, For integration parameters.

6. The control method for a three-rope parallel robot according to any one of claims 1 to 5, characterized in that, Controlling the motor operation based on the desired torque of the drive motor specifically includes: The motor control signal is obtained based on the relationship between the motor torque and the drive signal; The drive motor of the rope is controlled to run according to the motor control signal.

7. A control device for a three-rope parallel robot, characterized in that, A control method for performing the three-rope parallel robot as described in any one of claims 1 to 6; The control device includes: The desired trajectory acquisition module is used to acquire the desired trajectory sent by the host computer. The initial parameter acquisition module is used to acquire the desired position of the end effector and the desired torque of the drive motor based on the desired trajectory. The drive module is used to control the operation of the drive motor according to the desired torque of the drive motor; The actual parameter acquisition module is used to acquire the actual torque and actual speed of the drive motor output by the motor encoder; The torque compensation module is used to perform proportional-integral closed-loop compensation control on the drive motor based on the actual torque and the desired torque of the drive motor. The theoretical rope length acquisition module is used to integrate based on the actual rotational speed of the drive motor to obtain the theoretical rope length. The actual position acquisition module is used to obtain the actual position of the end effector by Newton's iteration method based on the theoretical rope length and the expected position as the initial value of the iteration. The position compensation module is used to perform closed-loop compensation control of the desired trajectory by proportional derivative based on the actual position and the desired position.

8. A control device for a three-rope parallel robot, characterized in that, It includes a processor, a memory, and a computer program stored in the memory; the computer program can be executed by the processor to implement the control method for a three-rope parallel robot as described in any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium includes a stored computer program, wherein, when the computer program is executed, it controls the device containing the computer-readable storage medium to perform the control method for a three-rope parallel robot as described in any one of claims 1 to 6.

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