Spider crane control system and control method based on multi-joint arm coordination

Abstract

The invention belongs to the technical field of intelligent hoisting equipment control, and discloses a spider crane control system and method based on multi-joint arm coordination, and the system comprises a data obtaining module which is used for obtaining multi-joint arm operation state data; the data processing module is used for preprocessing the operation state data of the multi-joint arm to obtain an operation state comprehensive feature data set; the fault prediction module is used for training according to the operation state comprehensive feature data set to obtain a crane fault prediction model, and predicting according to the crane fault prediction model to obtain a spider crane fault risk index; the fault processing module is used for judging whether fault processing is needed or not according to the predicted spider crane fault risk index; if the fault needs to be processed, fault early warning information is generated to remind an operator to process the fault; the outage rate of equipment is reduced, the cost for maintaining and replacing parts is reduced, and the service life of the equipment is prolonged; the operation fineness of the crane is improved, and the high efficiency and safety of the hoisting task are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent lifting equipment control, and more specifically, to a spider crane control system and a control method based on multi-joint arm coordination. Background Art

[0002] The patent with the patent announcement number CN111993414A discloses a method for controlling multi-joint linkage of a manipulator, the control method comprising, first, constructing a control system framework of the manipulator, the control system framework comprising a control layer, a model layer and a planning layer; secondly, constructing a fixed base coordinate system of the manipulator, a coordinate system of multiple arm joints and mathematical models of multiple arm joints in different configurations in the model layer; then, based on the mathematical models of multiple arm joints and the use conditions of the manipulator, constructing a kinematic inverse algorithm for different configurations of the manipulator in the control layer; finally, based on the kinematic inverse algorithm, planning the trajectory functions of each arm joint of the manipulator in the planning layer. The above control method and control system framework can be extended to general engineering machinery to achieve high-precision and intelligent control of engineering machinery.

[0003] The existing multi-joint arm coordinated spider crane control system and control method mainly have the following problems: In complex lifting operations, the existing control methods may not be able to fully cope with a variety of external interferences, and the system may have problems with insufficient joint angle control accuracy, especially in lifting tasks that require high precision, which may lead to errors in the position and posture of the end effector; dynamic update of joint angles is not considered, and oscillation is prone to occur during the update of joint angles, affecting the stability and smoothness of movement of the robot arm; impedance control is not considered to adjust the flexibility of the joint arm, and mechanical shock and vibration increase during the lifting process, which may damage the equipment and affect the lifting accuracy; The dynamically adjusted damping factor was not considered, and there was a lack of error compensation mechanism. The system had poor adaptability to environmental changes and work requirements and could not be adjusted flexibly, which affected the execution effect of the lifting task. The crane outrigger pressure data, articulated arm mass and position and other factors were not comprehensively considered, which may lead to inaccurate center of gravity calculation and affect safety assessment. The lack of multi-objective optimization led to an inability to balance energy efficiency and load vibration, which may lead to excessive energy consumption or increase mechanical vibration, affecting the long-term performance of the system and equipment life. The articulated arm's motion trajectory was not optimized, resulting in unnecessary acceleration and speed changes, increased motion energy consumption, reduced efficiency and shortened equipment life. Inaccurate joint torque control leads to asynchronous movements of the joints, making it impossible to accurately control the execution of the lifting task, which in turn affects the overall operation progress and quality; inconsistent joint movement may lead to reduced efficiency of the lifting operation and inability to efficiently complete complex tasks; unreasonable motion optimization will cause premature wear of the equipment, reduce the overall life span, and increase replacement and maintenance costs; due to unstable joint movements, the progress of the lifting operation may be affected and cannot be completed as planned.

[0004] In view of this, the present invention proposes a spider crane control system and a control method based on multi-joint arm coordination to solve the above problems. Summary of the invention

[0005] In order to overcome the above-mentioned defects of the prior art and to achieve the above-mentioned purpose, the present invention provides the following technical solution: a spider crane control system based on multi-joint arm coordination, comprising: A data acquisition module, used to acquire the operation status data of the multi-joint arm; A data processing module is used to pre-process the multi-joint arm operation status data to obtain a comprehensive feature data set of the operation status; A fault prediction module is used to obtain a crane fault prediction model based on the comprehensive feature data set of the operation status, and to predict the spider crane fault risk index based on the crane fault prediction model; The fault handling module is used to predict the spider crane fault risk index and determine whether fault handling is required; if fault handling is required, fault warning information is generated to remind the operator to handle the fault; The multi-joint arm collaborative control module generates a preliminary collaborative motion trajectory of the multi-joint arm based on a preset lifting operation task target if no fault processing is required or the fault has been processed; A stability control module is used to obtain the crane outrigger pressure data and the articulated arm posture data, and calculate the center of gravity offset of the vehicle body according to the crane outrigger pressure data and the articulated arm posture data; The collaborative stability optimization module is used to determine whether the center of gravity offset of the vehicle body exceeds the safety range. If it does not exceed the safety range, the preset lifting operation task objectives will continue to be executed; If it exceeds the safety range, the crane outrigger extension length and multi-joint arm load distribution are adjusted according to the center of gravity offset of the vehicle body, and the multi-objective optimization algorithm is used to obtain the optimal coordinated motion trajectory to complete the preset lifting operation task objectives; The modules are connected to each other via wired and / or wireless means.

[0006] Furthermore, the multi-joint arm operation status data includes motion status data, hoisting load data, joint force data and environmental disturbance data; The motion state data includes the angle of each joint, the speed of each joint, the acceleration of each joint, the position coordinates of the crane end effector and the joint drive current; the hoisting load data includes the load weight of the hoisted object, the center of gravity position of the hoisted object and the inclination angle of the hoisted object relative to the ground; the joint force data includes the positive pressure of each joint, the shear force of each joint, the torque of each joint and the load of the joint driver; the environmental disturbance data includes wind speed, wind direction, ground slope, temperature and ground slipperiness.

[0007] Furthermore, the method of preprocessing the multi-joint arm operation status data to obtain the operation status comprehensive feature data set includes: The principal component analysis is used to extract the features of the motion state data, the hoisting load data, the joint force data and the environmental disturbance data, and the motion state feature data set, the hoisting load feature data set, the joint force feature data set and the environmental disturbance feature data set are obtained; The motion state feature data set, hoisting load feature data set, joint force feature data set and environmental disturbance feature data set after feature extraction are normalized by standard deviation and converted into a standard normal distribution with a mean of 0 and a standard deviation of 1 to obtain the normalized motion state feature data set, hoisting load feature data set, joint force feature data set and environmental disturbance feature data set; the normalized motion state feature data set, hoisting load feature data set, joint force feature data set and environmental disturbance feature data set are weighted fused to obtain a comprehensive feature data set of the operating state.

[0008] Furthermore, the training method of the crane fault prediction model includes: The data set is divided into training set, validation set and test set to build a crane failure prediction model; the sample set is a subset of the data set, and each sample set includes a historical operation status comprehensive feature data set and a corresponding spider crane failure risk index; The crane fault prediction model includes an input layer, a GRU layer, a fully connected layer, and an output layer; the input layer of the model is used to input the historical operation status comprehensive feature data set, and the number of neurons in the input layer matches the number of features in the historical operation status comprehensive feature data set; The GRU layer is used to process the historical operation status comprehensive feature data set, and the number of GRU layers and the number of neurons are adjusted according to the task complexity; the fully connected layer is used to provide additional nonlinear transformation; the model output layer is used to output the spider crane failure risk index, and the predicted value is output through a neuron, and the identity function is used as the activation function; the crane failure prediction model is a gated recurrent unit model; Use mean absolute error as the loss function to measure the error between the model's predicted value and the actual value; use the training set data to train the model and minimize the loss function through the Adam optimizer; use the validation set to evaluate the performance of the model and tune the model's hyperparameters until the model performance no longer improves or reaches the preset stopping condition; The test set is used to evaluate the performance of the crane fault prediction model in the prediction task. The comprehensive feature dataset of the current operation status is input into the trained crane fault prediction model to obtain the spider crane fault risk index.

[0009] Further, judging whether fault handling is required based on the predicted spider crane fault risk index includes: comparing the predicted spider crane failure risk index with a preset spider crane failure risk index threshold; If the predicted spider crane failure risk index is greater than or equal to a preset spider crane failure risk index threshold, it is determined that failure processing is required; If the predicted spider crane failure risk index is less than a preset spider crane failure risk index threshold, it is determined that no failure processing is required.

[0010] Furthermore, the method for generating a preliminary coordinated motion trajectory of a multi-joint arm based on a preset lifting operation task target includes: By setting the lifting operation goals and constraints, the kinematic model and homogeneous transformation matrix are used to calculate the joint angles, so that the end effector of the articulated arm can accurately reach the preset target position and posture; the damped pseudo-inverse algorithm is used to dynamically update the joint angles, gradually reduce the error and optimize the adjustment process, and dynamically adjust the damping factor, and finally generate the time variation curve of each joint to form the preliminary coordinated motion trajectory of the multi-joint arm; S61, preset lifting task objectives include the initial state of the lifting task, the final state of the lifting task and lifting constraints; the lifting constraints include the maximum load offset, the maximum load tilt angle and the range of motion of the joint arm; the preset maximum load offset is , the preset maximum load tilt angle is , the preset range of motion of the joint arm is , ;in, is the joint angle; is the minimum joint angle; is the maximum joint angle; S62, calculate the joint angles that meet the lifting task objectives and the lifting constraints; establish a kinematic model of the multi-joint arm, and calculate the end position and posture of the joint arm through a homogeneous transformation matrix; the homogeneous transformation matrix is: ;in, Indicates the end position and posture of the articulated arm; Indicates joints At a given joint angle The posture below; Indicates the number of The homogeneous transformation matrix of the joints; Indicates The joint angles of the joints; Indicates the index of the joint; Indicates the number of joints; Said ;in, Indicates The rotation matrix of each joint; Indicates The translation vector of each joint; S63. Solve a set of joint angles , so that the end effector of the articulated arm reaches the preset target position and posture, that is: ;in, For a given joint angle Bottom, the position and posture of the end effector of the articulated arm; is the preset target location; S64, from the preset target position Start by calculating the preset target position Error from current end position According to the error Update the increment of joint angle through the damped pseudo-inverse formula ; The damped pseudo-inverse formula is: ;in, is the Jacobian matrix; is the transpose of the Jacobian matrix; is the damping factor; is the identity matrix; S65. Dynamically adjust the damping factor using a damping factor adjustment formula, wherein the damping factor adjustment formula is: ;in, is the maximum value of the damping factor; is the constant that adjusts the effect of error on the damping factor change; is the difference between the target joint angle and the current joint angle; S66, repeatedly update the increment of joint angle , gradually adjust the joint scheduling , until the current end position reaches the preset target position Stop at , and find the final joint angle ; S67, according to the solved joint angle , the time variation curve of each joint is initially generated. The curve of the angle variation of each joint over time describes the motion path of the joint arm, that is, the preliminary collaborative motion trajectory of the multi-joint arm; the preliminary collaborative motion trajectory is: ;in, Indicates exercise time The changing curve of each joint angle; Indicates Joints in motion time The angle of Indicates exercise time.

[0011] Furthermore, the method of obtaining the crane leg pressure data and the articulated arm posture data, and calculating the body center of gravity offset according to the crane leg pressure data and the articulated arm posture data includes: The crane leg pressure data includes the pressure of each leg and the position coordinates of each leg; the articulated arm posture data includes the position coordinates of each joint, the mass of each joint, the load mass at the end of the boom and the position coordinates of the end of the boom; The force center of the spider crane legs, the center of gravity of the articulated arms and the integrated center of gravity of the entire spider crane are calculated by using the crane leg pressure data and the articulated arm posture data; the overall center of gravity offset of the spider crane body is calculated by calculating the offset between the integrated center of gravity of the entire spider crane and the center of the spider crane chassis, and the steps include: S71. The spider crane is assumed to have four legs. The pressure data of the four legs of the spider crane are recorded as , , and The position coordinates of the four legs are , , and ; The force centers of the four legs of the spider crane are calculated by the weighted average formula. The weighted average formula is: ;in, is the horizontal coordinate of the force center of the outrigger; is the vertical coordinate of the force center of the outrigger; S72, preset spider crane has joints, and the position coordinates of each joint are ,in, is the index of the joint; the mass of each joint is The load mass at the end of the boom is , the coordinates of the end of the boom are ; Obtain the total mass of the joint arm through the total mass calculation formula of the joint arm ;in, is the sum of the masses of all joint parts on the articulated arm; S73, calculating the center of gravity of the joint arm using a formula for calculating the center of gravity of the joint arm; the formula for calculating the center of gravity of the joint arm is: ;in, is the horizontal coordinate of the center of gravity of the articulated arm; is the vertical coordinate of the center of gravity of the articulated arm; S74. Add the pressure data of the four legs of the spider crane to obtain the total force of the spider crane legs , combined with the position coordinates of the force center of the outrigger and the position coordinates of the center of gravity of the joint arm, the comprehensive center of gravity position coordinates of the entire spider crane are calculated by the comprehensive center of gravity calculation formula; the comprehensive center of gravity calculation formula is: ;in, It is the horizontal integrated center of gravity coordinate of the entire spider crane; is the vertical integrated center of gravity coordinate of the entire spider crane; S75, the center position coordinates of the spider crane chassis are preset as follows: , the offset between the comprehensive center of gravity coordinates of the entire spider crane and the center position coordinates of the spider crane chassis is calculated by the center of gravity offset calculation formula to obtain the center of gravity offset of the spider crane body; The calculation formula of the center of gravity offset is: ;in, is the horizontal offset of the comprehensive center of gravity coordinates of the entire spider crane relative to the center position coordinates of the spider crane chassis; is the vertical offset of the comprehensive center of gravity coordinates of the entire spider crane relative to the center position coordinates of the spider crane chassis; according to the horizontal offset and vertical offset of the center of gravity of the spider crane body, the overall offset of the center of gravity of the spider crane body is obtained .

[0012] Furthermore, the method for determining whether the center of gravity offset of the vehicle body exceeds a safe range includes: A safety threshold of the overall center of gravity offset is preset, and the preset safety threshold of the overall center of gravity offset is dynamically adjusted through an adaptive safety threshold formula to obtain a dynamically adjusted safety threshold of the overall center of gravity offset; according to the dynamically adjusted safety threshold of the overall center of gravity offset, whether the overall center of gravity offset of the spider crane body exceeds a safety range is determined; The adaptive safety threshold formula is: ;in, is the safety threshold of the overall center of gravity offset after dynamic adjustment; It is the safety threshold value of the preset center of gravity overall offset; The load type for the spider crane; is the operating speed of the spider crane; The slipperiness of the ground; is the load mass of the spider crane; is the load type influencing factor; is the operating speed influencing factor; is the factor affecting ground slipperiness; is the exponential factor; is the load quality influencing factor; The vehicle body center of gravity offset is compared with the dynamically adjusted overall center of gravity offset safety threshold. If the vehicle body center of gravity offset is greater than the dynamically adjusted overall center of gravity offset safety threshold, it is judged that the vehicle body center of gravity offset exceeds the safety range; if the vehicle body center of gravity offset is less than or equal to the dynamically adjusted overall center of gravity offset safety threshold, it is judged that the vehicle body center of gravity offset does not exceed the safety range.

[0013] Furthermore, the method of adjusting the telescopic length of the crane legs and the load distribution of the multi-joint arm according to the center of gravity offset of the vehicle body and obtaining the optimal coordinated motion trajectory by using a multi-objective optimization algorithm includes: According to the direction and magnitude of the center of gravity offset of the vehicle body, the telescopic length of the corresponding outrigger is adjusted to increase or decrease the outrigger extension; according to the center of gravity offset and the torque borne by each joint, the load ratio of each joint is adjusted to adjust the load distribution of the multi-joint arm; Based on the preliminary motion trajectory of the articulated arm, the compliance of the articulated arm is adjusted by introducing an impedance control equation, which is: in, is the joint mass matrix; is the damping matrix; is the stiffness matrix; is the expected trajectory angle; is the actual trajectory angle; is the acceleration of the joint angle; is the velocity of the joint angle; is the input joint torque; The input joint torque is adjusted in real time by the PD control formula, which is: ;in, is the stiffness control gain; is the damping control gain; Define trajectory optimization objectives, which include minimizing motion energy consumption, minimizing load vibration, and smoothing motion trajectory; construct optimization objective function: ;in, represents the optimal motion trajectory; Indicates Weighting factors associated with each joint; Indicates the total time of joint arm movement; Indicates The square of the velocity of each joint; Indicates The square of the acceleration of each joint; Regularization parameter representing the importance of equilibrium velocity and acceleration in the objective function; represents the time step; The optimal collaborative motion trajectory is finally obtained through the trajectory collaborative optimization formula, and the trajectory collaborative optimization formula is: ;in, is the optimal collaborative motion trajectory; is the desired end-effector velocity; is the joint velocity; is the square of the error between the desired end-effector velocity and the end-effector velocity calculated based on the joint velocities; is the sum of the squares of the weighted joint velocities; For in time The speed of the joint; is the desired end-effector velocity; is the joint velocity weight matrix; A regularization parameter that controls the effect of the regularization term on the optimization process.

[0014] The spider crane control method based on multi-joint arm coordination includes: S1. Obtaining multi-joint arm operation status data; S2. Preprocessing the multi-joint arm operation status data to obtain a comprehensive feature data set of the operation status; S3. A crane failure prediction model is obtained by training according to the comprehensive feature data set of the operation status, and a spider crane failure risk index is predicted according to the crane failure prediction model; S4. judging whether fault handling is required based on the predicted spider crane fault risk index; if fault handling is required, generating fault warning information to remind the operator to handle the fault; S5. If no fault processing is required or the fault has been processed, a preliminary coordinated motion trajectory of the multi-joint arm is generated based on a preset lifting operation task target; S6, obtaining the crane leg pressure data and the articulated arm posture data, and calculating the vehicle body center of gravity offset according to the crane leg pressure data and the articulated arm posture data; S7, judging whether the center of gravity deviation of the vehicle body exceeds the safety range, and if it does not exceed the safety range, continuing to execute the preset lifting operation task target; If it exceeds the safety range, the telescopic length of the crane legs and the load distribution of the multi-joint arm are adjusted according to the offset of the vehicle body's center of gravity; and the multi-objective optimization algorithm is used to obtain the optimal collaborative motion trajectory to complete the preset lifting operation task objectives.

[0015] The technical effects and advantages of the spider crane control system and control method based on multi-joint arm coordination of the present invention are as follows: The present invention achieves precise control of the joint angle by calculating the joint angle that meets the lifting operation target and meets the constraints such as load offset, tilt angle and joint arm motion range, so that the end effector can accurately reach the preset position and posture during the lifting operation; the joint angle is dynamically updated by the damped pseudo-inverse algorithm, which can effectively reduce the oscillation in the joint angle update process, gradually approach the target position, and optimize the entire motion process by adjusting the damping factor to avoid over-adjustment and improve motion efficiency; the introduction of dynamically adjusted damping factors and error compensation mechanisms can be flexibly adjusted according to the deviations occurring in the actual lifting task, thereby improving the system's adaptability to environmental changes and operation requirements; By comprehensively considering the pressure data of the crane legs, the mass and position coordinates of the articulated arms and other factors, the comprehensive center of gravity position of the spider crane is accurately calculated, providing a reliable basis for subsequent safety assessments; the adaptive safety threshold formula dynamically adjusts the safety threshold according to different load types, operating speeds, ground slipperiness and other factors, allowing the system to adjust the safety requirements for the center of gravity offset according to the actual operating environment and conditions. The flexible safety management method ensures that the crane can still maintain stability and safety in a changing working environment; the dynamically adjusted safety threshold is adjusted in real time based on the actual operating conditions, avoiding excessive or insufficient safety judgments that may be caused by fixed thresholds, thereby making the safety warnings of the crane more accurate in different environments; By introducing the impedance control equation, the flexibility of the articulated arm can be adjusted so that the joint can complete the lifting operation more smoothly and reduce mechanical shock and vibration; this is achieved by adjusting the stiffness matrix and the damping matrix to achieve precise control and optimize the motion performance; the input joint torque is adjusted in real time through the PD control formula, which can effectively control the motion behavior of the articulated arm, making the movement of each joint smoother, avoiding excessive mutations or vibrations, and ensuring the accuracy and safety of the lifting process; by defining multiple optimization objectives (such as minimizing motion energy consumption, reducing load vibration, smoothing motion trajectory, etc.), the contradictions between the various objectives can be balanced to achieve the best comprehensive performance; the optimization objective function can comprehensively consider the joint speed, acceleration and its changes during the motion process to ensure the smoothness and energy efficiency of the crane motion; the trajectory collaborative optimization formula can obtain the optimal joint motion trajectory, so that each joint of the articulated arm works in a coordinated manner, thereby ensuring that the end effector accurately reaches the expected target position. The optimization process takes into account the speed relationship between joints and the error between the expected and actual end-effector speeds, which can accurately control the execution of lifting tasks. By optimizing the trajectory, unnecessary motion acceleration and speed changes are reduced, and motion energy consumption and load vibration are effectively reduced, thereby extending equipment life, reducing maintenance costs, and improving lifting operation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the structure of the spider crane control system based on multi-joint arm coordination of the present invention; Figure 2 It is a schematic flow chart of the spider crane control method based on multi-joint arm coordination of the present invention. DETAILED DESCRIPTION

[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] Example 1 See also Figure 1 As shown, the spider crane control system based on multi-joint arm coordination in this embodiment includes: A data acquisition module, used to acquire the operation status data of the multi-joint arm; A data processing module is used to pre-process the multi-joint arm operation status data to obtain a comprehensive feature data set of the operation status; A fault prediction module is used to obtain a crane fault prediction model based on the comprehensive feature data set of the operation status, and to predict the spider crane fault risk index based on the crane fault prediction model; The fault handling module is used to determine whether fault handling is required based on the predicted spider crane fault risk index; if fault handling is required, fault warning information is generated to remind the operator to handle the fault; The multi-joint arm collaborative control module generates a preliminary collaborative motion trajectory of the multi-joint arm based on a preset lifting operation task target if no fault processing is required or the fault has been processed; A stability control module is used to obtain the crane outrigger pressure data and the articulated arm posture data, and calculate the center of gravity offset of the vehicle body according to the crane outrigger pressure data and the articulated arm posture data; The collaborative stability optimization module is used to determine whether the center of gravity offset of the vehicle body exceeds the safety range. If it does not exceed the safety range, the preset lifting operation task objectives will continue to be executed; If it exceeds the safety range, the crane outrigger extension length and multi-joint arm load distribution are adjusted according to the center of gravity offset of the vehicle body, and the multi-objective optimization algorithm is used to obtain the optimal coordinated motion trajectory to complete the preset lifting operation task objectives; The modules are connected to each other via wired and / or wireless means.

[0019] The multi-joint arm operation status data includes motion status data, hoisting load data, joint force data and environmental disturbance data; The motion state data includes the angle of each joint, the speed of each joint, the acceleration of each joint, the position coordinates of the crane end effector and the joint drive current; the hoisting load data includes the load weight of the hoisted object, the center of gravity position of the hoisted object and the inclination angle of the hoisted object relative to the ground; the joint force data includes the positive pressure of each joint, the shear force of each joint, the torque of each joint and the load of the joint driver; the environmental disturbance data includes wind speed, wind direction, ground slope, temperature and ground slipperiness.

[0020] The method of preprocessing the multi-joint arm operation state data to obtain the operation state comprehensive feature data set includes: The principal component analysis is used to extract the features of the motion state data, the hoisting load data, the joint force data and the environmental disturbance data, and the motion state feature data set, the hoisting load feature data set, the joint force feature data set and the environmental disturbance feature data set are obtained; The motion state feature data set, hoisting load feature data set, joint force feature data set and environmental disturbance feature data set after feature extraction are normalized by standard deviation and converted into a standard normal distribution with a mean of 0 and a standard deviation of 1 to obtain the normalized motion state feature data set, hoisting load feature data set, joint force feature data set and environmental disturbance feature data set; the normalized motion state feature data set, hoisting load feature data set, joint force feature data set and environmental disturbance feature data set are weighted fused to obtain a comprehensive feature data set of the operating state.

[0021] The training method of the crane failure prediction model includes: The data set is divided into training set, validation set and test set to build a crane failure prediction model; the sample set is a subset of the data set, and each sample set includes a historical operation status comprehensive feature data set and a corresponding spider crane failure risk index; The crane fault prediction model includes an input layer, a GRU layer, a fully connected layer, and an output layer; the input layer of the model is used to input the historical operation status comprehensive feature data set, and the number of neurons in the input layer matches the number of features in the historical operation status comprehensive feature data set; The GRU layer is used to process the historical operation status comprehensive feature data set, and the number of GRU layers and the number of neurons are adjusted according to the task complexity; the fully connected layer is used to provide additional nonlinear transformation; the model output layer is used to output the spider crane failure risk index, and the predicted value is output through a neuron, and the identity function is used as the activation function; the crane failure prediction model is a gated recurrent unit model; Use mean absolute error as the loss function to measure the error between the model's predicted value and the actual value; use the training set data to train the model and minimize the loss function through the Adam optimizer; use the validation set to evaluate the performance of the model and tune the model's hyperparameters until the model performance no longer improves or reaches the preset stopping condition; The test set is used to evaluate the performance of the crane fault prediction model in the prediction task. The comprehensive feature dataset of the current operation status is input into the trained crane fault prediction model to obtain the spider crane fault risk index.

[0022] According to the predicted spider crane failure risk index, whether fault handling is required includes: comparing the predicted spider crane failure risk index with a preset spider crane failure risk index threshold; If the predicted spider crane failure risk index is greater than or equal to a preset spider crane failure risk index threshold, it is determined that failure processing is required; If the predicted spider crane failure risk index is less than a preset spider crane failure risk index threshold, it is determined that no failure processing is required.

[0023] The method for generating a preliminary coordinated motion trajectory of a multi-joint arm based on a preset lifting operation task target includes: By setting the lifting operation goals and constraints, the kinematic model and homogeneous transformation matrix are used to calculate the joint angles, so that the end effector of the articulated arm can accurately reach the preset target position and posture; the damped pseudo-inverse algorithm is used to dynamically update the joint angles, gradually reduce the error and optimize the adjustment process, and dynamically adjust the damping factor, and finally generate the time variation curve of each joint to form the preliminary coordinated motion trajectory of the multi-joint arm; S61, preset lifting task objectives include the initial state of the lifting task, the final state of the lifting task and lifting constraints; the lifting constraints include the maximum load offset, the maximum load tilt angle and the range of motion of the joint arm; the preset maximum load offset is , the preset maximum load tilt angle is , the preset range of motion of the joint arm is , ;in, is the joint angle; is the minimum joint angle; is the maximum joint angle; S62, calculate the joint angles that meet the lifting task objectives and the lifting constraints; establish a kinematic model of the multi-joint arm, and calculate the end position and posture of the joint arm through a homogeneous transformation matrix; the homogeneous transformation matrix is: ;in, Represents the end position and posture of the articulated arm. It is the homogeneous transformation matrix of the end effector of the articulated arm. This matrix is ​​usually a 4x4 matrix that contains position (translation) and posture (rotation) information. Indicates joints At a given joint angle The pose (position and rotation) of the Indicates the number of The homogeneous transformation matrix of the joints; Indicates The joint angles of the joints; Indicates the index of the joint; Indicates the number of joints; Said ;in, Indicates The rotation matrix of each joint; Indicates The translation vector of each joint; S63. Solve a set of joint angles , so that the end effector of the articulated arm reaches the preset target position and posture, that is: ;in, For a given joint angle Bottom, the position and posture of the end effector of the articulated arm; is the preset target position, which indicates the position and posture that the end effector of the articulated arm is expected to reach; S64, from the preset target position Start by calculating the preset target position Error from current end position According to the error Update the increment of joint angle through the damped pseudo-inverse formula ; The damped pseudo-inverse formula is: ;in, is the Jacobian matrix; is the transpose of the Jacobian matrix; is the damping factor; is the identity matrix; S65. Dynamically adjust the damping factor using a damping factor adjustment formula, wherein the damping factor adjustment formula is: ;in, is the maximum value of the damping factor; is the constant that adjusts the effect of error on the damping factor change; is the difference between the target joint angle and the current joint angle; The damping factor adjustment formula smoothes the motion performance of the joint arm by dynamically adjusting the damping factor. When the error is small, the system can still maintain efficient and smooth motion; when the error is large, the rigidity is gradually increased to ensure effective motion adjustment; For example, the maximum value of the damping factor =1, the constant of the influence of adjustment error on the change of damping factor is 0.2; Assuming the target joint angle is 90° and the current joint angle is 89°, then ,So ; Assuming the target joint angle is 90° and the current joint angle is 70°, then ,So .

[0024] S66, repeatedly update the increment of joint angle , gradually adjust the joint scheduling , until the current end position reaches the preset target position Stop at , and find the final joint angle ; S67, according to the solved joint angle , the time variation curve of each joint is initially generated. The curve of the angle variation of each joint over time describes the motion path of the joint arm, that is, the preliminary collaborative motion trajectory of the multi-joint arm; the preliminary collaborative motion trajectory is: ;in, Indicates exercise time The change curve of each joint angle, that is, the change curve of the joint angle with the movement time The trajectory of change; Indicates Joints in motion time The angle of Indicates exercise time.

[0025] The technical issues addressed include: 1. Inaccurate calculation of joint angles: Traditional methods may have problems with insufficient accuracy or inability to accurately reach the target position when solving joint angles. This method establishes a kinematic model and combines the homogeneous transformation matrix and damped pseudo-inverse algorithm to accurately calculate the joint angles and ensure that the end effector accurately reaches the preset target.

[0026] 2. Error accumulation during motion: In the prior art, there is a risk of error accumulation in the adjustment of joint angles, which may result in the end effector being unable to accurately reach the target position. Through the damped pseudo-inverse algorithm and dynamic adjustment of the damping factor, this method can effectively reduce the error and optimize the adjustment process, preventing motion failure caused by excessive errors.

[0027] 3. Joint adjustment process is not smooth or too rigid: Existing methods may not be able to balance the smoothness and rigidity of joint adjustment, resulting in excessive oscillation or inflexible adjustment during the movement process. This method dynamically adjusts the damping factor to maintain smooth movement when the error is small and increase rigidity when the error is large, ensuring that the movement process is both efficient and stable.

[0028] 4. Unreasonable generation of collaborative motion trajectory: In the collaborative work of multi-joint arms, traditional methods may fail to take into account the collaborative influence between joints, resulting in unreasonable motion trajectory. This method effectively coordinates the motion of multiple joints by repeatedly updating the joint angles and generating time change curves to ensure that each joint works together to complete the lifting task.

[0029] 5. Insufficient consideration of lifting operation constraints: Existing methods may ignore the constraints in lifting tasks, such as load offset, tilt angle, and joint arm motion range, which affects the safety and effectiveness of the operation. This method fully considers these constraints when solving the joint angle to ensure the safety and accuracy of the lifting task.

[0030] Beneficial effects achieved include: By combining the kinematic model with the homogeneous transformation matrix, the angles of each joint are accurately calculated, thus ensuring that the end effector of the multi-joint arm accurately reaches the preset target position and posture during the lifting operation, improving the overall operation accuracy; By using the damped pseudo-inverse algorithm and dynamically adjusting the damping factor, the increment of the joint angle is accurately updated, which effectively reduces the error accumulation during the joint adjustment process, ensures the accurate motion trajectory of the joint arm, and improves the stability of the movement. By dynamically adjusting the damping factor, smooth movement is maintained when the error is small, and rigidity is increased when the error is large, ensuring that the joint arm can be adjusted efficiently and smoothly under different error conditions, avoiding excessive rigidity or oscillating movement; The generated time variation curves of each joint can effectively coordinate the movement of each joint, ensure the cooperation between multi-joint arms, make the lifting operation more efficient and accurate, and avoid unreasonable joint movement; By considering constraints such as the maximum load offset, maximum tilt angle, and range of motion of the articulated arm, it is ensured that while the lifting mission objectives are met, the safety and stability of the operation are improved.

[0031] Through the dynamic adjustment of the damping factor, the system can flexibly adapt to changes in different working environments, improve the adaptability and stability of the overall system, and ensure the smooth completion of the task.

[0032] The method of obtaining the crane outrigger pressure data and the articulated arm posture data, and calculating the body center of gravity offset according to the crane outrigger pressure data and the articulated arm posture data includes: The crane leg pressure data includes the pressure of each leg and the position coordinates of each leg; the articulated arm posture data includes the position coordinates of each joint, the mass of each joint, the load mass at the end of the boom and the position coordinates of the end of the boom; The force center of the spider crane legs, the center of gravity of the articulated arms and the integrated center of gravity of the entire spider crane are calculated by using the crane leg pressure data and the articulated arm posture data; the overall center of gravity offset of the spider crane body is calculated by calculating the offset between the integrated center of gravity of the entire spider crane and the center of the spider crane chassis, and the steps include: S71. The spider crane is assumed to have four legs. The pressure data of the four legs of the spider crane are recorded as , , and The position coordinates of the four legs are , , and ; The force center of the four legs of the spider crane is calculated by the weighted average formula, combining the pressure of each leg with its position coordinates. This force center reflects the combined force point of the four legs, which affects the stability and inclination of the crane. The weighted average formula is: ;in, is the horizontal coordinate of the force center of the outrigger; is the vertical coordinate of the force center of the outrigger; S72, preset spider crane has joints, and the position coordinates of each joint are ,in, is the index of the joint; the mass of each joint is The load mass at the end of the boom is , the coordinates of the end of the boom are ; Obtain the total mass of the joint arm through the total mass calculation formula of the joint arm ;in, is the sum of the masses of all joint parts on the articulated arm; S73. Calculate the center of gravity of the joint arm using the formula for calculating the center of gravity of the joint arm; the center of gravity caused by the load of the joint arm is a comprehensive effect of the mass, coordinates of each joint and the position of the end load. Calculate the center of gravity of the joint arm using the formula for calculating the center of gravity of the joint arm, and combine the mass and position of the end load to obtain the comprehensive center of gravity. The formula for calculating the center of gravity of the joint arm is: ;in, is the horizontal coordinate of the center of gravity of the articulated arm; is the vertical coordinate of the center of gravity of the articulated arm; S74. Add the pressure data of the four legs of the spider crane to obtain the total force of the spider crane legs , combined with the position coordinates of the force center of the outrigger and the position coordinates of the center of gravity of the joint arm, the comprehensive center of gravity position coordinates of the entire spider crane are calculated by the comprehensive center of gravity calculation formula; the comprehensive center of gravity calculation formula is: ;in, It is the horizontal integrated center of gravity coordinate of the entire spider crane; is the vertical integrated center of gravity coordinate of the entire spider crane; S75, the center position coordinates of the spider crane chassis (i.e. the theoretically ideal center of gravity coordinates) are preset as follows: , the offset between the comprehensive center of gravity coordinates of the entire spider crane and the center position coordinates of the spider crane chassis is calculated by the center of gravity offset calculation formula to obtain the center of gravity offset of the spider crane body; The calculation formula of the center of gravity offset is: ;in, is the horizontal offset of the comprehensive center of gravity coordinates of the entire spider crane relative to the center position coordinates of the spider crane chassis; is the vertical offset of the comprehensive center of gravity coordinates of the entire spider crane relative to the center position coordinates of the spider crane chassis; according to the horizontal offset and vertical offset of the center of gravity of the spider crane body, the overall offset of the center of gravity of the spider crane body is obtained .

[0033] Methods for determining whether the center of gravity offset of the vehicle body exceeds the safe range include: A safety threshold of the overall center of gravity offset is preset, and the preset safety threshold of the overall center of gravity offset is dynamically adjusted through an adaptive safety threshold formula to obtain a dynamically adjusted safety threshold of the overall center of gravity offset; according to the dynamically adjusted safety threshold of the overall center of gravity offset, whether the overall center of gravity offset of the spider crane body exceeds a safety range is determined; The adaptive safety threshold formula is: ;in, is the safety threshold of the overall center of gravity offset after dynamic adjustment; It is the safety threshold value of the overall offset of the preset center of gravity; The load type of the spider crane (e.g. whether it is a uniformly distributed load, concentrated load, etc.); is the operating speed of the spider crane; The slipperiness of the ground, usually the coefficient of friction, ranges from 0 to 1 (the greater the friction, the less slippery the ground); is the load mass of the spider crane; is the load type influencing factor, which is used to adjust the impact of the spider crane's load type on the safety threshold of the overall center of gravity offset; is the operating speed influencing factor, which is used to adjust the effect of the spider crane's operating speed on the safety threshold of the overall center of gravity offset; is the influence factor of ground slipperiness, which is used to adjust the linear influence of ground slipperiness on the safety threshold of the overall center of gravity offset; is an exponential factor used to adjust the nonlinear effect of ground slipperiness on the safety threshold of the overall center of gravity offset; is the load mass influencing factor, which is used to adjust the impact of the spider crane's load mass on the safety threshold of the overall center of gravity offset; For example, preset the safety threshold of the overall center of gravity offset is 100, the load type of the spider crane There are 4 types of spider crane operating speeds. 3m / s, ground slipperiness is 0.6, the load mass of the spider crane =8, load type influence factor =0.2, the operation speed influence factor is 0.3, the floor slipperiness factor is 0.4, the load quality influence factor is 0.1, exponential factor is 2, then the dynamically adjusted center of gravity overall offset safety threshold .

[0034] According to the importance of the load type influencing factor on adjusting the spider crane's operating speed to the safety threshold of the overall center of gravity offset, set the influencing factor The initial value range is: 0.1 0.3, the initial default value is 0.2, if the load type has a greater impact on safety (such as uneven load or very heavy load), increase the impact factor On the contrary, if the load type has little impact on safety (such as stable load and meets the design standards), the impact factor is reduced. The weight factor is optimized in real time according to the load type in actual work to ensure that the safety threshold of the crane can be improved in time under extreme load conditions (such as overweight or uneven load).

[0035] According to the importance of the operating speed influencing factor in adjusting the spider crane's operating speed on the safety threshold of the overall center of gravity offset, the influencing factor is set. The initial value range is: 0.2 0.4, the initial default value is 0.3. If the operation speed is fast and has a significant impact on the stability of the crane (for example, the crane is prone to vibration or tilt during high-speed operation), the impact factor needs to be appropriately increased. If the operation speed is slow or the impact on the crane is small, reduce the impact factor The weight of According to the importance of the ground slipperiness factor in adjusting the spider crane's operating speed to the safety threshold of the overall center of gravity offset, the influence factor is set. The initial value range is: 0.3 0.5, the initial default value is 0.4. If the slipperiness has a strong impact on safety (such as operating in rainy and snowy weather), increase the impact factor If the slipperiness has little impact on safety (such as good weather conditions), then reduce The weight of .

[0036] According to the importance of the ground slipperiness factor in adjusting the spider crane's operating speed to the safety threshold of the overall center of gravity offset, the influence factor is set. The initial value range is: 0 0.2, the initial default value is 0.1. If the load is large (such as overweight or abnormal load), the impact factor needs to be increased The value of can be adjusted to improve the safety of the crane. For smaller loads, the impact factor can be reduced accordingly. The weight of .

[0037] The vehicle body center of gravity offset is compared with the dynamically adjusted overall center of gravity offset safety threshold. If the vehicle body center of gravity offset is greater than the dynamically adjusted overall center of gravity offset safety threshold, it is judged that the vehicle body center of gravity offset exceeds the safety range; if the vehicle body center of gravity offset is less than or equal to the dynamically adjusted overall center of gravity offset safety threshold, it is judged that the vehicle body center of gravity offset does not exceed the safety range.

[0038] The technical issues addressed include: 1. Fixed safety threshold lacks adaptability: Traditional methods usually use fixed safety thresholds to determine the center of gravity offset, which cannot adapt to different working environments and conditions. This makes the safety threshold too loose or too strict in some complex or extreme situations, resulting in safety hazards or waste of resources.

[0039] 2. Lack of dynamic adjustment of environmental factors: Existing technologies fail to consider the real-time changes in the operating environment, such as the impact of operating speed, ground slipperiness, etc. on the safety of the center of gravity offset. These environmental factors have a significant impact in actual operations, and failure to dynamically adjust the safety threshold will lead to inaccurate safety judgments.

[0040] 3. Failure to consider the difference in load type and mass: Existing methods ignore the impact of different load types (such as uniformly distributed loads or concentrated loads) and their mass on the center of gravity offset. The type and mass of the load will directly affect the stability of the crane, so the safety threshold needs to be dynamically adjusted according to the actual load conditions.

[0041] 4. Failure to deal with nonlinear influencing factors: The existing technology fails to fully consider the nonlinear effects of factors such as wetness on the center of gravity offset. For example, in extreme weather conditions, the wetness of the ground has a more significant impact on the stability of the crane, and the traditional method fails to flexibly adjust the safety threshold according to environmental changes; 5. Unable to cope with complex dynamic working conditions: In traditional technologies, the safety judgment of the center of gravity offset is based on static models or simple algorithms, which cannot effectively cope with the changes in the center of gravity offset caused by the changes in various parameters during the operation under dynamic working conditions; 6. Problems of delayed response and untimely risk assessment: When faced with rapidly changing operating conditions (such as changes in load or sudden changes in operating speed), existing technologies have delayed responses and are unable to dynamically adjust safety thresholds in real time, which may result in missing the best opportunity to determine that the center of gravity offset exceeds the safety range.

[0042] Beneficial effects achieved include: By dynamically adjusting the safety threshold of the center of gravity offset, it is possible to respond to different operating conditions, environmental changes and load conditions in real time, thus effectively avoiding the safety hazards caused by the fixed threshold in the traditional method. The dynamic threshold makes safety judgment more accurate and improves the overall safety of the spider crane.

[0043] Taking into account the dynamic influence of multiple factors such as operating speed, load type, ground slipperiness, etc., the safety threshold can be flexibly adjusted to cope with different operating environments and complex operating conditions, ensuring the stability of the crane in various environments.

[0044] By adjusting the weights of influencing factors according to real-time load type, operating speed and other parameters, the crane can optimize the safety threshold according to actual conditions in different working environments, making the system more flexible, intelligent and adaptable.

[0045] It can better simulate the nonlinear effect of slipperiness on the safety threshold of the center of gravity and improve the accuracy of safety assessment.

[0046] Through the adaptive dynamic adjustment mechanism, it can respond to changes in real time, thereby improving the real-time safety protection during crane operation.

[0047] The method of adjusting the telescopic length of the crane legs and the load distribution of the multi-joint arm according to the center of gravity offset of the vehicle body and obtaining the optimal coordinated motion trajectory by using a multi-objective optimization algorithm includes: According to the direction and magnitude of the center of gravity offset of the vehicle body, the telescopic length of the corresponding outrigger is adjusted to increase or decrease the outrigger extension; according to the center of gravity offset and the torque borne by each joint, the load ratio of each joint is adjusted to adjust the load distribution of the multi-joint arm; Based on the preliminary motion trajectory of the joint arm, the impedance control equation is introduced to adjust the flexibility of the joint arm so that when it is disturbed by external factors (such as load swing or environmental collision), it can properly adjust its own motion instead of rigidly resisting external forces, thereby reducing impact and vibration. The impedance control equation is: in, is the joint mass matrix, which is used to describe the inertial characteristics of the joint; is the damping matrix, used to control compliance; is the stiffness matrix, which represents the deviation between the expected trajectory angle and the actual trajectory angle; is the expected trajectory angle; is the actual trajectory angle; is the acceleration of the joint angle; is the velocity of the joint angle; is the input joint torque; The input joint torque is adjusted in real time by the PD control formula, which is: ;in, is the stiffness control gain; It is the damping control gain; it allows the joint to deviate slightly from the desired trajectory under external disturbances, thereby reducing stress and load sway; Define trajectory optimization objectives, which include minimizing motion energy consumption, minimizing load vibration, and smoothing motion trajectory; construct optimization objective function: ;in, represents the optimal motion trajectory; Indicates Weighting factors associated with each joint; Indicates the total time of joint arm movement; Indicates The square of the velocity of each joint; Indicates The square of the acceleration of each joint; Regularization parameter representing the importance of equilibrium velocity and acceleration in the objective function; represents the time step, which is used to integrate acceleration and velocity; The optimal collaborative motion trajectory is finally obtained through the trajectory collaborative optimization formula, and the trajectory collaborative optimization formula is: ;in, is the optimal collaborative motion trajectory; is the desired end-effector velocity; is the joint velocity; is the square of the error between the desired end-effector velocity and the end-effector velocity calculated based on the joint velocities; is the sum of the squares of the weighted joint velocities; For in time The speed of the joint; is the desired end-effector velocity; is the joint velocity weight matrix; A regularization parameter that controls the effect of the regularization term on the optimization process.

[0048] The technical issues addressed include: 1. Insufficient consideration of the impact of the body center of gravity offset on the crane stability: Most traditional crane systems do not dynamically consider the impact of the body center of gravity offset on the crane stability, outrigger extension and retraction, and multi-jointed arm load distribution.

[0049] 2. Problems of insufficient precision in outrigger extension and load distribution: In the prior art, outrigger extension and load distribution often rely on preset modes and lack a real-time feedback mechanism.

[0050] 3. Lack of flexibility in motion control under external interference: In the prior art, the multi-jointed arm of the crane is prone to severe vibration or impact when encountering external interference, affecting the stability of the crane operation.

[0051] 4. Insufficient multi-objective optimization and coordinated motion trajectory design: In the existing technology, the motion trajectory design of crane joints often only considers a single goal (such as reducing energy consumption or stability), and lacks coordinated optimization of multiple objectives.

[0052] 5. Inflexible joint torque adjustment problem: Traditional methods often rely on fixed control strategies when controlling joint torque, which is not flexible.

[0053] 6. Lack of motion energy efficiency optimization for different working conditions: Traditional motion control methods often do not fully consider energy efficiency optimization under different operating conditions (such as load type, operating speed, environmental interference, etc.).

[0054] 7. The motion trajectory is not smooth enough and has a large vibration problem: The motion trajectory in the prior art is often affected by environmental changes and loads, resulting in vibration or unevenness of the trajectory.

[0055] 8. Insufficient regularization control in the optimization process: In the traditional optimization process, there is often a lack of reasonable regularization for different constraints.

[0056] Beneficial effects achieved include: By adjusting the outrigger extension length and joint load distribution according to the direction and magnitude of the vehicle body's center of gravity offset, it can respond to different load conditions and working environments in real time, improving the overall stability and safety of the crane.

[0057] By dynamically adjusting the telescopic length of the outriggers and the load distribution according to the center of gravity offset of the vehicle body, the method can accurately adjust the outriggers and articulated arms of the crane according to actual working conditions, thereby improving the stability and operating efficiency of the crane under different load conditions.

[0058] By introducing the impedance control equation and adjusting the compliance of the articulated arm, this method can enable the articulated arm to properly adjust its movement when subjected to force interference (such as load swing or environmental collision), avoid rigid resistance to external forces, reduce impact and vibration, and ensure stable operation of the crane.

[0059] Through trajectory optimization objective function, minimizing motion energy consumption, reducing load vibration and smoothing motion trajectory are taken into account. The collaborative optimization formula is used to achieve comprehensive optimization of multiple objectives, providing a more intelligent and refined motion trajectory control solution.

[0060] By using the PD control formula to adjust the joint input torque in real time, this method can adjust the control gain according to the real-time status (such as load, speed, external interference), achieve the flexibility and flexible control of joint movement, and improve the adaptability of the system.

[0061] Through trajectory optimization functions and multi-objective optimization, this method can adjust various control parameters in real time to ensure the optimal motion energy efficiency under various working conditions, avoiding the energy waste problem in traditional methods.

[0062] By introducing regularized parameters of acceleration and velocity and optimizing the velocity and acceleration of the joints, the motion trajectory can be effectively smoothed, vibration problems caused by trajectory jitter and instability can be reduced, and the comfort and stability of the crane during operation can be improved.

[0063] By designing regularization control terms and weight matrices, the optimization process of various parameters can be precisely controlled to ensure that the final solution is more in line with actual work needs, thereby achieving an optimal balance between multiple objectives.

[0064] The preset spider crane failure risk index threshold is set by the staff, and the spider crane failure risk index is collected through the spider crane control terminal, and the average value of multiple spider crane failure risk indexes is taken as the preset spider crane failure risk index threshold; similarly, the overall center of gravity offset safety threshold is preset.

[0065] In this embodiment, the joint angles that meet the lifting operation objectives are calculated, and the constraints such as load offset, tilt angle, and joint arm motion range are met to achieve precise control of the joint angles, so that the end effector can accurately reach the preset position and posture during the lifting operation; the joint angles are dynamically updated by the damped pseudo-inverse algorithm, which can effectively reduce the oscillation in the joint angle update process, gradually approach the target position, and optimize the entire motion process by adjusting the damping factor to avoid over-adjustment and improve motion efficiency; the introduction of dynamically adjusted damping factors and error compensation mechanisms can be flexibly adjusted according to the deviations that occur in actual lifting tasks, thereby improving the system's adaptability to environmental changes and operational requirements; By comprehensively considering the pressure data of the crane legs, the mass and position coordinates of the articulated arms and other factors, the comprehensive center of gravity position of the spider crane is accurately calculated, providing a reliable basis for subsequent safety assessments; the adaptive safety threshold formula dynamically adjusts the safety threshold according to different load types, operating speeds, ground slipperiness and other factors, allowing the system to adjust the safety requirements for the center of gravity offset according to the actual operating environment and conditions. The flexible safety management method ensures that the crane can still maintain stability and safety in a changing working environment; the dynamically adjusted safety threshold is adjusted in real time based on the actual operating conditions, avoiding excessive or insufficient safety judgments that may be caused by fixed thresholds, thereby making the safety warnings of the crane more accurate in different environments; By introducing the impedance control equation, the flexibility of the articulated arm can be adjusted so that the joint can complete the lifting operation more smoothly and reduce mechanical shock and vibration; this is achieved by adjusting the stiffness matrix and the damping matrix to achieve precise control and optimize the motion performance; the input joint torque is adjusted in real time through the PD control formula, which can effectively control the motion behavior of the articulated arm, making the movement of each joint smoother, avoiding excessive mutations or vibrations, and ensuring the accuracy and safety of the lifting process; by defining multiple optimization objectives (such as minimizing motion energy consumption, reducing load vibration, smoothing motion trajectory, etc.), the contradictions between the various objectives can be balanced to achieve the best comprehensive performance; the optimization objective function can comprehensively consider the joint speed, acceleration and its changes during the motion process to ensure the smoothness and energy efficiency of the crane motion; the trajectory collaborative optimization formula can obtain the optimal joint motion trajectory, so that each joint of the articulated arm works in a coordinated manner, thereby ensuring that the end effector accurately reaches the expected target position. The optimization process takes into account the speed relationship between joints and the error between the expected and actual end-effector speeds, which can accurately control the execution of lifting tasks. By optimizing the trajectory, unnecessary motion acceleration and speed changes are reduced, and motion energy consumption and load vibration are effectively reduced, thereby extending equipment life, reducing maintenance costs, and improving lifting operation efficiency.

[0066] Example 2 See also Figure 2As shown, the part not described in detail in this embodiment can be found in the description of embodiment 1, which provides a spider crane control method based on multi-joint arm coordination, including: S1. Obtaining multi-joint arm operation status data; S2. Preprocessing the multi-joint arm operation status data to obtain a comprehensive feature data set of the operation status; S3. A crane failure prediction model is obtained by training according to the comprehensive feature data set of the operation status, and a spider crane failure risk index is predicted according to the crane failure prediction model; S4. judging whether fault handling is required based on the predicted spider crane fault risk index; if fault handling is required, generating fault warning information to remind the operator to handle the fault; S5. If no fault processing is required or the fault has been processed, a preliminary coordinated motion trajectory of the multi-joint arm is generated based on a preset lifting operation task target; S6, obtaining the crane leg pressure data and the articulated arm posture data, and calculating the vehicle body center of gravity offset according to the crane leg pressure data and the articulated arm posture data; S7, judging whether the center of gravity deviation of the vehicle body exceeds the safety range, and if it does not exceed the safety range, continuing to execute the preset lifting operation task target; If it exceeds the safety range, the telescopic length of the crane legs and the load distribution of the multi-joint arm are adjusted according to the offset of the vehicle body's center of gravity; and the multi-objective optimization algorithm is used to obtain the optimal collaborative motion trajectory to complete the preset lifting operation task objectives.

[0067] Since the electronic device introduced in this embodiment is an electronic device used to implement the spider crane control system and control method based on multi-joint arm coordination in the embodiment of this application, based on the spider crane control system and control method based on multi-joint arm coordination introduced in the embodiment of this application, the technical personnel in this field can understand the specific implementation of the electronic device of this embodiment and its various variations, so how the electronic device implements the method in the embodiment of this application will not be described in detail here. As long as the technical personnel in this field implement the electronic device used in the spider crane control system and control method based on multi-joint arm coordination in the embodiment of this application, it belongs to the scope of protection of this application.

[0068] The above formulas are all dimensionless and numerical calculations. The formula is a formula for the most recent real situation obtained by collecting a large amount of data and performing software simulation. The preset parameters and thresholds in the formula are set by technicians in this field according to actual conditions.

[0069] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technical users in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A spider crane control system based on multi-joint arm coordination, characterized in that: include: A data acquisition module, used to acquire the operation status data of the multi-joint arm; A data processing module is used to pre-process the multi-joint arm operation status data to obtain a comprehensive feature data set of the operation status; A fault prediction module is used to obtain a crane fault prediction model based on the comprehensive feature data set of the operation status, and to predict the spider crane fault risk index based on the crane fault prediction model; A fault handling module is used to determine whether fault handling is required based on the predicted spider crane fault risk index; If fault handling is required, fault warning information is generated to remind the operator to handle the fault; The multi-joint arm collaborative control module generates a preliminary collaborative motion trajectory of the multi-joint arm based on a preset lifting operation task target if no fault processing is required or the fault has been processed; A stability control module is used to obtain the crane outrigger pressure data and the articulated arm posture data, and calculate the center of gravity offset of the vehicle body according to the crane outrigger pressure data and the articulated arm posture data; The collaborative stability optimization module is used to determine whether the center of gravity offset of the vehicle body exceeds the safety range. If it does not exceed the safety range, the preset lifting operation task objectives will continue to be executed; If it exceeds the safety range, the crane outrigger extension length and multi-joint arm load distribution are adjusted according to the center of gravity offset of the vehicle body, and the multi-objective optimization algorithm is used to obtain the optimal coordinated motion trajectory to complete the preset lifting operation task objectives; The modules are connected to each other via wired and / or wireless means.

2. The spider crane control system based on multi-joint arm coordination according to claim 1 is characterized in that: The multi-joint arm operation state data includes motion state data, hoisting load data, joint force data and environmental disturbance data; The motion state data includes the angle of each joint, the speed of each joint, the acceleration of each joint, the position coordinates of the crane end effector and the joint drive current; the hoisting load data includes the load weight of the hoisted object, the center of gravity position of the hoisted object and the inclination angle of the hoisted object relative to the ground; the joint force data includes the positive pressure of each joint, the shear force of each joint, the torque of each joint and the load of the joint driver; the environmental disturbance data includes wind speed, wind direction, ground slope, temperature and ground slipperiness.

3. The spider crane control system based on multi-joint arm coordination according to claim 2 is characterized in that: The method of preprocessing the multi-joint arm operation state data to obtain the operation state comprehensive feature data set comprises: The principal component analysis is used to extract the features of the motion state data, the hoisting load data, the joint force data and the environmental disturbance data, and the motion state feature data set, the hoisting load feature data set, the joint force feature data set and the environmental disturbance feature data set are obtained; The motion state feature data set, hoisting load feature data set, joint force feature data set and environmental disturbance feature data set after feature extraction are normalized by standard deviation and converted into a standard normal distribution with a mean of 0 and a standard deviation of 1 to obtain the normalized motion state feature data set, hoisting load feature data set, joint force feature data set and environmental disturbance feature data set; the normalized motion state feature data set, hoisting load feature data set, joint force feature data set and environmental disturbance feature data set are weighted fused to obtain a comprehensive feature data set of the operating state.

4. The spider crane control system based on multi-joint arm coordination according to claim 3 is characterized in that: The training method of the crane fault prediction model includes: The data set is divided into training set, validation set and test set to build a crane failure prediction model; the sample set is a subset of the data set, and each sample set includes a historical operation status comprehensive feature data set and a corresponding spider crane failure risk index; The crane fault prediction model includes an input layer, a GRU layer, a fully connected layer, and an output layer; the input layer of the model is used to input the historical operation status comprehensive feature data set, and the number of neurons in the input layer matches the number of features in the historical operation status comprehensive feature data set; The GRU layer is used to process the historical operation status comprehensive feature data set, and the number of GRU layers and the number of neurons are adjusted according to the task complexity; the fully connected layer is used to provide additional nonlinear transformation; the model output layer is used to output the spider crane failure risk index, and the predicted value is output through a neuron, and the identity function is used as the activation function; the crane failure prediction model is a gated recurrent unit model; Use mean absolute error as the loss function to measure the error between the model's predicted value and the actual value; use the training set data to train the model and minimize the loss function through the Adam optimizer; use the validation set to evaluate the performance of the model and tune the model's hyperparameters until the model performance no longer improves or reaches the preset stopping condition; The test set is used to evaluate the performance of the crane fault prediction model in the prediction task. The comprehensive feature dataset of the current operation status is input into the trained crane fault prediction model to obtain the spider crane fault risk index.

5. The spider crane control system based on multi-joint arm coordination according to claim 4 is characterized in that: The determining whether fault handling is required based on the predicted spider crane fault risk index includes: comparing the predicted spider crane failure risk index with a preset spider crane failure risk index threshold; If the predicted spider crane failure risk index is greater than or equal to a preset spider crane failure risk index threshold, it is determined that failure processing is required; If the predicted spider crane failure risk index is less than a preset spider crane failure risk index threshold, it is determined that no failure processing is required.

6. The spider crane control system based on multi-joint arm coordination according to claim 5, characterized in that: The method for generating a preliminary coordinated motion trajectory of a multi-joint arm based on a preset lifting operation task target comprises: By setting the lifting operation goals and constraints, the kinematic model and homogeneous transformation matrix are used to calculate the joint angles, so that the end effector of the articulated arm can accurately reach the preset target position and posture; the damped pseudo-inverse algorithm is used to dynamically update the joint angles, gradually reduce the error and optimize the adjustment process, and dynamically adjust the damping factor, and finally generate the time variation curve of each joint to form the preliminary coordinated motion trajectory of the multi-joint arm; S61, preset lifting task objectives include the initial state of the lifting task, the final state of the lifting task and lifting constraints; the lifting constraints include the maximum load offset, the maximum load tilt angle and the range of motion of the joint arm; the preset maximum load offset is , the preset maximum load tilt angle is , the preset range of motion of the joint arm is , ;in, is the joint angle; is the minimum joint angle; is the maximum joint angle; S62, calculate the joint angles that meet the lifting task objectives and the lifting constraints; establish a kinematic model of the multi-joint arm, and calculate the end position and posture of the joint arm through a homogeneous transformation matrix; the homogeneous transformation matrix is: ;in, Indicates the end position and posture of the articulated arm; Indicates joints At a given joint angle The posture below; Indicates the number of The homogeneous transformation matrix of the joints; Indicates The joint angles of the joints; Indicates the index of the joint; Indicates the number of joints; Said ;in, Indicates The rotation matrix of each joint; Indicates The translation vector of each joint; S63. Solve a set of joint angles , so that the end effector of the articulated arm reaches the preset target position and posture, that is: ;in, For a given joint angle Bottom, the position and posture of the end effector of the articulated arm; is the preset target location; S64, from the preset target position Start by calculating the preset target position Error from current end position According to the error Update the increment of joint angle through the damped pseudo-inverse formula ; The damped pseudo-inverse formula is: ;in, is the Jacobian matrix; is the transpose of the Jacobian matrix; is the damping factor; is the identity matrix; S65. Dynamically adjust the damping factor using a damping factor adjustment formula, wherein the damping factor adjustment formula is: ;in, is the maximum value of the damping factor; is the constant that adjusts the effect of error on the damping factor change; is the difference between the target joint angle and the current joint angle; S66, repeatedly update the increment of joint angle , gradually adjust the joint scheduling , until the current end position reaches the preset target position Stop at , and find the final joint angle ; S67, according to the solved joint angle , the time variation curve of each joint is initially generated. The curve of the angle variation of each joint over time describes the motion path of the joint arm, that is, the preliminary collaborative motion trajectory of the multi-joint arm; the preliminary collaborative motion trajectory is: ;in, Indicates exercise time The changing curve of each joint angle; Indicates Joints in motion time The angle of Indicates exercise time.

7. The spider crane control system based on multi-joint arm coordination according to claim 6, characterized in that: The method of obtaining the crane leg pressure data and the articulated arm posture data, and calculating the body center of gravity offset according to the crane leg pressure data and the articulated arm posture data comprises: The crane leg pressure data includes the pressure of each leg and the position coordinates of each leg; the articulated arm posture data includes the position coordinates of each joint, the mass of each joint, the load mass at the end of the boom and the position coordinates of the end of the boom; The force center of the spider crane legs, the center of gravity of the articulated arms and the integrated center of gravity of the entire spider crane are calculated by using the crane leg pressure data and the articulated arm posture data; the overall center of gravity offset of the spider crane body is calculated by calculating the offset between the integrated center of gravity of the entire spider crane and the center of the spider crane chassis, and the steps include: S71. The spider crane is assumed to have four legs. The pressure data of the four legs of the spider crane are recorded as , , and The position coordinates of the four legs are , , and ; The force centers of the four legs of the spider crane are calculated by the weighted average formula. The weighted average formula is: ;in, is the horizontal coordinate of the force center of the outrigger; is the vertical coordinate of the force center of the outrigger; S72, preset spider crane has joints, and the position coordinates of each joint are ,in, is the index of the joint; the mass of each joint is The load mass at the end of the boom is , the coordinates of the end of the boom are ; Obtain the total mass of the joint arm through the total mass calculation formula of the joint arm ;in, is the sum of the masses of all joint parts on the articulated arm; S73, calculating the center of gravity of the joint arm using a formula for calculating the center of gravity of the joint arm; the formula for calculating the center of gravity of the joint arm is: ;in, is the horizontal coordinate of the center of gravity of the articulated arm; is the vertical coordinate of the center of gravity of the articulated arm; S74. Add the pressure data of the four legs of the spider crane to obtain the total force of the spider crane legs , combined with the position coordinates of the force center of the outrigger and the position coordinates of the center of gravity of the joint arm, the comprehensive center of gravity position coordinates of the entire spider crane are calculated by the comprehensive center of gravity calculation formula; the comprehensive center of gravity calculation formula is: ;in, It is the horizontal integrated center of gravity coordinate of the entire spider crane; is the vertical integrated center of gravity coordinate of the entire spider crane; S75, the center position coordinates of the spider crane chassis are preset as follows: , the offset between the comprehensive center of gravity coordinates of the entire spider crane and the center position coordinates of the spider crane chassis is calculated by the center of gravity offset calculation formula to obtain the center of gravity offset of the spider crane body; The calculation formula of the center of gravity offset is: ;in, is the horizontal offset of the comprehensive center of gravity coordinates of the entire spider crane relative to the center position coordinates of the spider crane chassis; is the vertical offset of the comprehensive center of gravity coordinates of the entire spider crane relative to the center position coordinates of the spider crane chassis; according to the horizontal offset and vertical offset of the center of gravity of the spider crane body, the overall offset of the center of gravity of the spider crane body is obtained .

8. The spider crane control system based on multi-joint arm coordination according to claim 7, characterized in that: The method for determining whether the center of gravity offset of the vehicle body exceeds a safe range includes: A safety threshold of the overall center of gravity offset is preset, and the preset safety threshold of the overall center of gravity offset is dynamically adjusted through an adaptive safety threshold formula to obtain a dynamically adjusted safety threshold of the overall center of gravity offset; according to the dynamically adjusted safety threshold of the overall center of gravity offset, whether the overall center of gravity offset of the spider crane body exceeds a safety range is determined; The adaptive safety threshold formula is: ;in, is the safety threshold of the overall center of gravity offset after dynamic adjustment; It is the safety threshold value of the preset center of gravity overall offset; The load type for the spider crane; is the operating speed of the spider crane; The slipperiness of the ground; is the load mass of the spider crane; is the load type influencing factor; is the operating speed influencing factor; is the factor affecting ground slipperiness; is the exponential factor; is the load quality influencing factor; The vehicle body center of gravity offset is compared with the dynamically adjusted overall center of gravity offset safety threshold. If the vehicle body center of gravity offset is greater than the dynamically adjusted overall center of gravity offset safety threshold, it is judged that the vehicle body center of gravity offset exceeds the safety range; if the vehicle body center of gravity offset is less than or equal to the dynamically adjusted overall center of gravity offset safety threshold, it is judged that the vehicle body center of gravity offset does not exceed the safety range.

9. The spider crane control system based on multi-joint arm coordination according to claim 8, characterized in that: The method of adjusting the telescopic length of the crane legs and the load distribution of the multi-joint arm according to the center of gravity offset of the vehicle body and obtaining the optimal coordinated motion trajectory by using a multi-objective optimization algorithm includes: According to the direction and magnitude of the center of gravity offset of the vehicle body, the telescopic length of the corresponding outrigger is adjusted to increase or decrease the outrigger extension; according to the center of gravity offset and the torque borne by each joint, the load ratio of each joint is adjusted to adjust the load distribution of the multi-joint arm; Based on the preliminary motion trajectory of the articulated arm, the compliance of the articulated arm is adjusted by introducing an impedance control equation, which is: in, is the joint mass matrix; is the damping matrix; is the stiffness matrix; is the expected trajectory angle; is the actual trajectory angle; is the acceleration of the joint angle; is the velocity of the joint angle; is the input joint torque; The input joint torque is adjusted in real time by the PD control formula, which is: ;in, is the stiffness control gain; is the damping control gain; Define trajectory optimization objectives, which include minimizing motion energy consumption, minimizing load vibration, and smoothing motion trajectory; construct optimization objective function: ;in, represents the optimal motion trajectory; Indicates Weighting factors associated with each joint; Indicates the total time of joint arm movement; Indicates The square of the velocity of each joint; Indicates The square of the acceleration of each joint; Regularization parameter representing the importance of equilibrium velocity and acceleration in the objective function; represents the time step; The optimal collaborative motion trajectory is finally obtained through the trajectory collaborative optimization formula, and the trajectory collaborative optimization formula is: ;in, is the optimal collaborative motion trajectory; is the desired end-effector velocity; is the joint velocity; is the square of the error between the desired end-effector velocity and the end-effector velocity calculated based on the joint velocities; is the sum of the squares of the weighted joint velocities; For in time The speed of the joint; is the desired end-effector velocity; is the joint velocity weight matrix; A regularization parameter that controls the effect of the regularization term on the optimization process.

10. A spider crane control method based on multi-joint arm coordination, used to implement the spider crane control system based on multi-joint arm coordination as claimed in any one of claims 1 to 9, characterized in that: include: S1. Obtaining multi-joint arm operation status data; S2. Preprocessing the multi-joint arm operation status data to obtain a comprehensive feature data set of the operation status; S3. A crane failure prediction model is obtained by training according to the comprehensive feature data set of the operation status, and a spider crane failure risk index is predicted according to the crane failure prediction model; S4. judging whether fault handling is required according to the predicted spider crane fault risk index; If fault handling is required, fault warning information is generated to remind the operator to handle the fault; S5. If no fault processing is required or the fault has been processed, a preliminary coordinated motion trajectory of the multi-joint arm is generated based on a preset lifting operation task target; S6, obtaining the crane leg pressure data and the articulated arm posture data, and calculating the vehicle body center of gravity offset according to the crane leg pressure data and the articulated arm posture data; S7, judging whether the center of gravity deviation of the vehicle body exceeds the safety range, and if it does not exceed the safety range, continuing to execute the preset lifting operation task target; If it exceeds the safety range, the telescopic length of the crane legs and the load distribution of the multi-joint arm are adjusted according to the offset of the vehicle body's center of gravity; and the multi-objective optimization algorithm is used to obtain the optimal collaborative motion trajectory to complete the preset lifting operation task objectives.

Images