A method and system for adaptive parameter tuning of a portal crane grab swing prevention control

Abstract

The application discloses a kind of self-adapting parameter setting gantry crane grab bucket anti-sway control method and system, belong to door machine control technical field, method includes using first motor control frequency and / or second motor control frequency control door machine carries out rotation and / or luffing action;The mode for obtaining first motor control frequency is: constructing luffing distance factor and rotation angle factor, the maximum angular velocity under current working condition is dynamically corrected;Carry out grab bucket rotation planning, and the angular velocity of rotation planning is converted into first motor control frequency;The mode for obtaining second motor control frequency is: obtaining the maximum linear velocity of grab bucket, using S-curve trajectory planning method carries out grab bucket luffing planning;The linear velocity of grab bucket rotation planning is nonlinearly mapped into second motor control frequency with the pitch angle of boom support.This application can realize the dynamic optimization of anti-sway trajectory, eliminate the conversion error of luffing anti-sway trajectory, enhance system robustness and positioning accuracy.

Description

An adaptive parameter tuning method and system for anti-sway control of grab bucket in gantry cranes Technical Field

[0001] This invention belongs to the field of gantry crane control technology, specifically relating to an adaptive parameter tuning method and system for anti-sway control of the grab bucket of a gantry crane. Background Technology

[0002] As a core piece of equipment for port loading and unloading, the anti-sway control of the grab bucket in automated operations of gantry cranes directly affects the efficiency and safety of automated operations. The grab bucket is connected by a flexible wire rope, and under the drive of the wire rope, it can move up and down, forward and backward, and left and right in a circular motion (the trajectory is arc-shaped). The grab bucket's swaying mainly stems from the lag in its movement when following the luffing and rotating mechanisms of the gantry crane. Excessive swaying of the grab bucket can also cause accidents. Traditional gantry cranes rely on manual operation, where personnel use experience to control the grab bucket and prevent swaying, but the anti-sway effect varies from person to person. Existing methods for preventing grab bucket swaying include: using sensors such as encoders, inclinometers, and QR code cameras to collect mechanism position parameters for high-precision positioning; and S-shaped acceleration and deceleration trajectory planning: widely used for smooth motion control, ensuring continuous acceleration through a 7-segment segmented polynomial (Jerk controllable). The angular velocity curves of the rotating mechanism and the linear velocity curves of the luffing mechanism are usually designed as S-shaped (including three stages: acceleration, constant speed, and deceleration) to reduce the swing of the grab bucket. The rotation and luffing mechanisms are controlled by offline parameter tuning (such as fixing the maximum angular velocity and acceleration / deceleration time) and frequency commands output by the PLC or motion controller to drive the motor.

[0003] However, existing technologies have the following shortcomings:

[0004] (1) The anti-sway trajectory cannot dynamically adapt to the working conditions, resulting in unstable anti-sway effect.

[0005] Without considering the anti-sway distance, a constant maximum speed is used to plan the uniform speed segment trajectory. For rotating mechanisms, the lack of coupling between the rotation radius and the anti-sway distance can lead to excessive centrifugal force when the rotation radius is small, causing the grab bucket to overshoot (the speed does not decrease with the radius, causing the inertial force to exceed the anti-sway threshold); when the rotation radius is large, a fixed low speed leads to a longer motion time and reduced work efficiency (the speed does not adapt to the radius, resulting in insufficient utilization of the mechanism's load-bearing capacity). The same applies to luffing mechanisms.

[0006] (2) The linear conversion from variable amplitude linear velocity to motor frequency only considers the additional sway caused by linear conversion.

[0007] In the four-bar linkage mechanism of the gantry crane, there is a nonlinear mapping relationship between the linear velocity of the elephant trunk head and the linear velocity of the luffing rack. Directly converting the motor frequency command according to the linear ratio causes the actual movement of the elephant trunk to deviate from the planned trajectory, and the grab bucket to produce a secondary swing. Summary of the Invention

[0008] To address the shortcomings of existing technologies, this invention provides an adaptive parameter tuning method and system for anti-sway control of the grab bucket of a gantry crane. This method enables dynamic optimization of the anti-sway trajectory, eliminates conversion errors in the luffing anti-sway trajectory, and enhances system robustness and positioning accuracy.

[0009] This invention provides the following technical solution:

[0010] In a first aspect, an adaptive parameter tuning method for anti-sway control of grab bucket of gantry crane is provided, comprising: controlling the gantry crane to perform rotation and / or luffing actions by using the control frequency of a first motor and / or the control frequency of a second motor;

[0011] The first motor control frequency is used to drive the grab bucket to rotate. The method for obtaining the first motor control frequency is as follows:

[0012] The system collects the luffing amplitude and target rotation angle of the grab bucket under the current working conditions in real time, constructs luffing distance factor and rotation angle factor, and then dynamically corrects the maximum angular velocity under the current working conditions after weighted fusion of luffing distance factor and rotation angle factor.

[0013] Based on the corrected maximum angular velocity, the S-curve trajectory planning method is used to plan the rotation of the grab bucket, and the angular velocity of the rotation plan is converted into the control frequency of the first motor.

[0014] The second motor control frequency is used to drive the grab bucket's luffing motion. The method for obtaining the second motor control frequency is as follows:

[0015] The maximum linear velocity of the grab is obtained based on the target luffing range, and the luffing range is planned using the S-curve trajectory planning method. Based on the target luffing range, the pitch angle of the boom is obtained using the inverse kinematic relationship between the boom and the grab, and the pitch angle of the boom and the planned linear velocity of the grab are nonlinearly mapped to the control frequency of the second motor through the speed transfer model.

[0016] Optionally, the amplitude distance factor for:

[0017] ;

[0018] in, This refers to the luffing range of the grab bucket under current operating conditions. and These are the maximum and minimum amplitude limits for the amplitude-changing mechanism, respectively.

[0019] The rotation angle factor for:

[0020] ;

[0021] in, The reference angle scaling factor is k, and the curve steepness coefficient is k. Rotate by the target angle;

[0022] After weighted fusion of amplitude distance factor and rotation angle factor, the comprehensive influence factor is obtained. :

[0023] ;

[0024] in, Angle weighting factor;

[0025] The dynamic correction of the maximum angular velocity under the current operating condition is specifically as follows:

[0026] ;

[0027] in, The maximum angular velocity under the current operating condition after dynamic correction. This represents the initial maximum angular velocity.

[0028] Optionally, the step of using the S-curve trajectory planning method to plan the grab rotation based on the corrected maximum angular velocity specifically involves:

[0029] Adjust the angle according to the target. and the maximum angular velocity after dynamic correction Calculate the total motion time of the grab bucket rotation. Based on the total motion time of the grab bucket rotation, the S-curve trajectory planning method is used to plan the grab bucket rotation, and the angular velocity of the grab bucket rotation plan is obtained. and rotation trajectory;

[0030] ;

[0031] in, This is the time gain coefficient used to adjust the total rotation time to adapt to changing operating conditions.

[0032] Optionally, the step of obtaining the maximum linear velocity of the grab based on the target luffing amplitude and using the S-curve trajectory planning method for grab luffing amplitude planning specifically involves:

[0033] Calculate the maximum linear velocity of the grab bucket ;

[0034] ;

[0035] in, and These are the maximum and minimum limiting linear velocities of the grab bucket's end motion, respectively. This is the curve steepness coefficient. The target amplitude of the grab bucket, To smooth the midpoint;

[0036] Calculate the total motion time of the grab bucket luffing. ;

[0037] ;

[0038] in, This is the time gain coefficient used to adjust the total amplitude variation time to adapt to changing operating conditions;

[0039] Total motion time based on grab bucket amplitude variation The S-curve trajectory planning method is used to plan the luffing of the grab bucket, and the linear velocity and luffing trajectory of the luffing plan are obtained.

[0040] Optionally, based on the target amplitude, the boom pitch angle is solved using inverse kinematics, and the boom pitch angle and the planned linear velocity of the grab are nonlinearly mapped to the control frequency of the second motor through a velocity transfer model. Specifically:

[0041] Based on the geometric constraints of the boom and grab, a forward kinematic model is established to calculate the amplitude using the pitch angle. Then, based on this forward kinematic model, the inverse kinematic relationship is solved, utilizing the amplitude... Solve for the boom's pitch angle. ;

[0042] Using the boom's pitch angle and the grab's planned linear velocity, the speed of the second motor driving the luffing motion is calculated through a speed transmission model, and based on the relationship between motor speed and frequency, the speed of the second motor is converted into the control frequency of the second motor.

[0043] The speed transmission model is represented as follows:

[0044] ;

[0045] in, To control the rotational speed of the second motor driving the luffing motion, Let be the linear velocity at time t. and These are two velocity transfer coefficients related to the forward kinematics model.

[0046] Optionally, during the process of controlling the gantry crane to perform rotation and / or luffing movements using the control frequency of the first motor and / or the control frequency of the second motor, disturbances are monitored in real time, and when disturbances are detected, the angular velocity and / or linear velocity are reduced by a gradient deceleration method until the grab bucket comes to a complete stop.

[0047] After the grab bucket comes to a complete stop, the disturbance is continuously monitored, and after the disturbance disappears, the grab bucket rotation planning and / or luffing planning are re-performed to regain the control frequency of the first motor and / or the control frequency of the second motor until the grab bucket reaches the target position.

[0048] Optionally, during the process of controlling the gantry crane to perform rotation and / or luffing movements using the first motor control frequency and / or the second motor control frequency, the position of the grab bucket is acquired in real time. Based on the planned position and the real-time position of the grab bucket, the luffing position deviation and / or rotation position deviation of the grab bucket are calculated. It is determined whether the luffing position deviation and / or rotation position deviation are greater than the corresponding set threshold. If so, the currently planned first motor control frequency and / or second motor control frequency are maintained. Otherwise, the frequency reduction coefficient under the current deviation is obtained by using the pre-set relationship between the position deviation and the frequency reduction coefficient. The obtained frequency reduction coefficient K is used to correct the first motor control frequency and / or the second motor control frequency until the target position is reached.

[0049] ;

[0050] in, For the corrected first motor control frequency and / or second motor control frequency, The first motor control frequency and / or the second motor control frequency before correction.

[0051] Secondly, an adaptive parameter tuning anti-sway control system for a gantry crane grab bucket is provided, comprising:

[0052] The control layer is used to issue the first motor control frequency and / or the second motor control frequency;

[0053] The execution layer is used to control the gantry crane to perform rotation and / or luffing movements;

[0054] The perception layer is used to collect the amplitude of the grab bucket and the rotation angle of the target in real time under the current working conditions.

[0055] The control layer includes:

[0056] The rotational motion control module is used to obtain the control frequency of the first motor. Specifically, it constructs a variable amplitude distance factor and a rotation angle factor, and after weighted fusion of the variable amplitude distance factor and the rotation angle factor, dynamically corrects the maximum angular velocity under the current working condition; based on the corrected maximum angular velocity, it uses the S-curve trajectory planning method to plan the rotation of the grab bucket, and converts the angular velocity of the rotation plan into the control frequency of the first motor.

[0057] The variable amplitude motion control module is used to obtain the control frequency of the second motor. Specifically, it obtains the maximum linear velocity of the grab based on the target variable amplitude of the grab, and uses the S-curve trajectory planning method to plan the variable amplitude of the grab; based on the target variable amplitude, it obtains the pitch angle of the boom using the inverse kinematic relationship between the boom and the grab, and nonlinearly maps the pitch angle of the boom and the planned linear velocity of the grab to the control frequency of the second motor through the speed transfer model.

[0058] Thirdly, a computer device is provided, including a processor and a memory; wherein, when the processor executes a computer program stored in the memory, it implements the steps of the adaptive parameter tuning anti-sway control method for a gantry crane grab bucket as described in any one of the first aspects.

[0059] Fourthly, a computer-readable storage medium is provided for storing a computer program; when the computer program is executed by a processor, it implements the steps of the adaptive parameter tuning anti-sway control method for a gantry crane grab bucket as described in any one of the first aspects.

[0060] Compared with the prior art, the beneficial effects of the present invention are:

[0061] (1) This application dynamically couples the luffing distance factor of the gantry crane, which represents the real-time rotation radius, with the rotation angle factor, which represents the difference in target angle, to achieve adaptive tuning of the maximum angular velocity of the gantry crane. Based on this dynamically tuned maximum angular velocity, combined with a mature S-shaped acceleration and deceleration trajectory planning algorithm, it can smoothly, efficiently, and intelligently adapt to the rotation anti-sway under different luffing distances and rotation angles.

[0062] (2) This application dynamically plans the linear velocity, sets the maximum variable amplitude linear velocity, and combines a high-precision nonlinear mapping model to eliminate the speed transmission error of the four-bar linkage composed of the boom and the grab bucket, so that the actual linear velocity at the end of the grab bucket deviates significantly from the planned velocity, and eliminates secondary oscillation caused by mechanical characteristics.

[0063] (3) This application breaks through the limitations of traditional methods that rely solely on initial trajectory planning. It dynamically corrects the control frequency during the movement of the gantry crane, thereby further reducing the dynamic tracking error. It solves the problem of having a good planned trajectory but a large actual execution deviation. It also designs a stable stop-start anti-disturbance mode to achieve smooth braking of the grab bucket when a disturbance is triggered, and automatically replans the trajectory to the target point after the disturbance disappears. Attached Figure Description

[0064] Figure 1 is a flowchart of the steps of the adaptive parameter tuning method for the anti-sway control of the grab bucket of a gantry crane according to the present invention;

[0065] Figure 2 shows the design objective of the present invention for dynamically tuning the maximum angular velocity;

[0066] Figure 3 is a flowchart of the linear velocity nonlinear mapping to the second control frequency for the planning of the variable amplitude motion of the present invention;

[0067] Figure 4 is a flowchart of the disturbance-stabilization process of the present invention;

[0068] Figure 5 is a flowchart of the dynamic correction control frequency of the present invention;

[0069] Figure 6 is a structural block diagram of the adaptive parameter tuning gantry crane grab bucket anti-sway control system of the present invention;

[0070] Figure 7 is a structural block diagram of the control layer in another type of anti-sway control system for gantry crane grab bucket of the present invention;

[0071] Figure 8 is a schematic diagram of the four-bar gantry crane structure in the inverse kinematics model of the present invention;

[0072] Figure 9 is a schematic diagram of the initial parameters of the four-bar gantry crane in the inverse kinematics model of the present invention. Detailed Implementation

[0073] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and should not be used to limit the scope of protection of the present invention. It should be noted that the term "comprising" and any variations thereof in the specification, claims and the above-mentioned drawings of the present invention are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or devices.

[0074] Example 1

[0075] As shown in Figure 1, an adaptive parameter tuning method for anti-sway control of the grab bucket of a gantry crane includes: controlling the gantry crane to perform rotation and / or luffing movements using the control frequency of a first motor and / or the control frequency of a second motor.

[0076] 1. Drive the grab bucket to rotate and obtain the first motor control frequency.

[0077] S1.1: Real-time acquisition of the luffing amplitude and target rotation angle of the grab under the current working condition, constructing luffing distance factor and rotation angle factor, and then weighted and fused the luffing distance factor and rotation angle factor to dynamically correct the maximum angular velocity under the current working condition.

[0078] In traditional methods for sway prevention during the rotation of gantry cranes, the maximum angular velocity during the uniform speed phase is typically used. Setting the value to a constant can easily lead to grab overshoot under small rotation radius conditions and excessive anti-swaying under large rotation radius conditions, thus reducing operating efficiency. To overcome this limitation, a dynamic calculation model for the maximum angular velocity integrating two factors is proposed to achieve accurate calculation of the maximum angular velocity. Perform dynamic tuning.

[0079] As shown in Figure 2, for the maximum angular velocity The goal of the tuning is to maintain high-speed motion when the grab bucket moves a long distance to the target angle (Δx(t) > Δx / 2, Δθ is relatively large), and to achieve smooth deceleration and effectively suppress overshoot when approaching the target (Δx(t) < Δx / 2, Δθ is relatively small). By establishing a safe working range with minimum angular velocity, it is ensured that the rotating mechanism can maintain its base speed under small angle difference (Δθ is extremely small) conditions, avoiding stagnation, thereby achieving the best balance between efficiency and anti-sway accuracy.

[0080] The core of the dual-factor maximum angular velocity dynamic calculation model lies in the dynamic coupling of the amplitude-range factor. and rotation angle factor At the same time, angle weights are introduced. Adaptive solution for the maximum permissible angular velocity of the anti-sway mechanism of the rotating mechanism The model input is the real-time amplitude. Difference between rotation angle and target .

[0081] Using a dynamic calculation model for maximum angular velocity fused with two factors, the maximum angular velocity is calculated. The specific method for dynamic tuning is as follows:

[0082] S1.1.1: Construct the amplitude distance factor based on the current amplitude x of the grab bucket. :

[0083] ;

[0084] in, This refers to the luffing range of the grab bucket under current operating conditions. and These are the maximum and minimum amplitude limits for the amplitude regulating mechanism; amplitude distance factor. Characterizing the constraint of the current grab position on the velocity: when x is large, Approaching 1 allows for higher speeds; when x is small, Approaching zero, speed is limited to suppress overshoot. A safe zone is set to ensure... At extremely low speeds, maintain the base speed to avoid stalling.

[0085] S1.1.2: Constructing the rotation angle factor using the improved Sigmoid function :

[0086] ;

[0087] in, The reference angle scaling factor is used to... Mapping to the reasonable range of variation of the Sigmoid function, where k is the curve steepness coefficient. Rotate by the target angle; when hour, Approaching 1, it supports high-speed motion; when hour, Approaching 0, it achieves a progressive speed limit based on the angle difference.

[0088] S1.1.3: A weighted fusion method is used to combine the amplitude distance factor and the rotation angle factor to obtain the comprehensive influence factor. :

[0089] ;

[0090] in, This is the angle weighting factor, used to adjust the relative importance of the angle difference factor in the fusion calculation.

[0091] S1.1.4: Dynamically correct the maximum angular velocity under the current operating condition, specifically as follows:

[0092] ;

[0093] in, The maximum angular velocity under the current operating condition after dynamic correction. This is the initial maximum angular velocity, which is the reference value of the maximum angular velocity under the initial settings before dynamic correction.

[0094] By properly allocating weighting factors Steepness coefficient k and reference angle Achieve coefficient The adaptive adjustment, dynamic coupling of amplitude and rotational motion constraints, drives the gantry crane to its maximum angular velocity. It can self-tune according to changes in operating conditions.

[0095] S1.2: Based on the corrected maximum angular velocity, the S-curve trajectory planning method is used to plan the rotation of the grab bucket, and the angular velocity of the rotation plan is converted into the control frequency of the first motor.

[0096] S1.2.1: Maximum angular velocity based on secondary tuning A seven-segment S-curve is used for angular velocity trajectory planning to ensure continuity of position, velocity, acceleration, and jerk, thus improving motion stability. The core of the time allocation design is to determine the time parameters for each stage based on the total angular change, and the total motion time of the grab's rotation. Determined by the following formula:

[0097] ;

[0098] in, This is the time gain coefficient used to adjust the total rotation time to adapt to changing operating conditions.

[0099] S1.2.2: Considering the anti-sway efficiency and the smoothness of the grab bucket running to the end of the trajectory, the total time is proportionally allocated to the acceleration segment T1, uniform acceleration segment T2, deceleration segment T3, uniform speed segment T4, acceleration and deceleration segment T5, uniform deceleration segment T6 and deceleration segment T7.

[0100] ;

[0101] in, To accelerate the total time of the segment, The total time for the deceleration phase is defined by T1=T3 and T5=T7. The symmetry between the acceleration and deceleration phases is ensured by constraining T1=T3 and T5=T7. By allocating a longer time for the acceleration / deceleration phase T5 and the deceleration / deceleration phase T7, the acceleration of the grab bucket at the speed transition from motion to deceleration is ensured to be more continuous and smooth, and the rate of change of acceleration is controllable, avoiding sudden changes in acceleration that could cause the grab bucket to swing.

[0102] S1.2.3: To simplify the calculation of angular velocity during the uniform velocity segment, the integral coefficient A for the acceleration segment and the integral coefficient B for the deceleration segment are defined as follows. Their physical meaning is the "equivalent uniform velocity time" of the acceleration and deceleration segments:

[0103] ;

[0104] Then the angular velocity w of the final uniform velocity segment can be determined. s for:

[0105] ;

[0106] At this point, the angular accelerations during the acceleration and deceleration phases are respectively:

[0107] ;

[0108] The expressions for angular acceleration and angular deceleration are:

[0109] ;

[0110] The expressions for the angular velocity and angular trajectory of the S-curve are:

[0111]

[0112]

[0113] in, Indicates the current time The offset relative to the start time of each stage can be uniformly defined as the offset for the first stage. Each stage ( ),definition ,in For the first The start time of the phase, This refers to the duration of each sub-phase. During the deceleration phase... , where n is the index of the last sub-stage of the deceleration phase.

[0114] S1.2.4: To ensure the angle value is within [0, 2...] Within the specified range, the final angle position needs to be normalized.

[0115] .

[0116] S1.2.5: In the actual operation of the gantry crane, the rotating mechanism is driven by a motor. Therefore, in order for the rotating mechanism to accurately follow the planned trajectory and achieve precise motor drive control, the planned angular velocity needs to be... The control frequency of the first motor that drives the rotary mechanism is converted into the control frequency. :

[0117] ;

[0118] in, , and These represent the reduction ratio, slip, and number of pole pairs of the first motor, respectively. Substituting these expressions into the piecewise angular velocity function yields the piecewise programming function for the frequency of the first motor of the rotating mechanism.

[0119] 2. Drive the grab bucket to change amplitude and obtain the control frequency of the second motor.

[0120] S2.1 The maximum linear velocity of the grab is obtained based on the target amplitude of the grab, and the S-curve trajectory planning method is used for grab amplitude planning.

[0121] When the gantry crane's luffing mechanism reaches the target position, its anti-sway effect is mainly limited by the target luffing distance. To ensure the grab can operate at the desired maximum linear velocity during the constant-speed phase, a smoothed sigmoid function is used to achieve the maximum linear velocity of the elephant's trunk head driven by a single factor. Dynamic programming was employed. A mature S-shaped acceleration / deceleration trajectory planning algorithm was combined with a variable amplitude motion time allocation strategy to plan the end trajectory of the anti-sway grab bucket of the variable amplitude mechanism.

[0122] S2.1.1: Introduce the Sigmoid function to calculate the maximum linear velocity of the grab bucket. ;

[0123] ;

[0124] in, and These represent the maximum and minimum limiting linear velocities of the grab bucket's end motion during the luffing motion of a gantry crane. This is the curve steepness coefficient, which controls the rate of increase of the maximum output linear velocity. The target amplitude of the grab bucket, To smooth the midpoint, the central region controls the speed change.

[0125] Using this function to tune the optimal maximum uniform linear velocity can avoid sudden velocity changes and ensure that the maximum linear velocity is positively correlated with the amplitude change distance. This can be achieved by adjusting k. This enables high adaptability to different gantry crane models and operating scenarios.

[0126] S2.1.2: Calculate the total motion time of the grab bucket's luffing. ;

[0127] ;

[0128] in, This is the time gain coefficient used to adjust the total amplitude variation time to adapt to changing operating conditions.

[0129] S2.1.3: Define the time distribution ratio for the entire amplitude change motion. The integral coefficient A for the acceleration segment and the integral coefficient B for the deceleration segment are both consistent with those for the rotational motion. At this time, the linear velocity of the uniform segment is determined during the secondary tuning. for:

[0130] ;

[0131] At this point, the acceleration and deceleration jerkes are respectively:

[0132] ;

[0133] The expressions for acceleration and deceleration are:

[0134] ;

[0135] The expressions for the linear velocity and amplitude trajectory of the S-curve are:

[0136] ;

[0137] ;

[0138] S2.2: Based on the target luffing amplitude, the pitch angle of the boom is obtained by using the inverse kinematic relationship between the boom and the grab, and the pitch angle of the boom and the planned linear velocity of the grab are nonlinearly mapped into the control frequency of the second motor driving the luffing motion through the velocity transfer model.

[0139] Due to the nonlinear mechanical characteristics of the four-bar linkage of the gantry crane, the linear velocity of the grab bucket is not constant when the luffing rack moves at a constant speed. The trajectory planning speed is the linear velocity of the elephant trunk head. In order to control the grab bucket, a trajectory planning dummy can be installed. It is necessary to establish a nonlinear mapping model from the linear velocity of the elephant trunk head to the control frequency of the motor driving the luffing motion.

[0140] As shown in Figure 3, it specifically includes:

[0141] S2.2.1: Based on the geometric constraints of the boom and grab, establish a forward kinematic model for calculating the amplitude using the pitch angle, and then solve the inverse kinematic relationship based on the forward kinematic model, using the amplitude... Solve for the boom's pitch angle. .

[0142] The trajectory planning output is the amplitude x, while the velocity transfer model requires the pitch angle N as input. Therefore, an inverse kinematics model from x to N needs to be established. Existing technologies can be referenced for the inverse kinematics model.

[0143] Specifically, the forward kinematic model is first solved. This application focuses on a four-bar gantry crane, as shown in Figures 8 and 9. The four-bar gantry crane includes a boom, a main tie rod, a trunk beam, and a luffing motor. The luffing motor drives the boom to adjust the trunk beam's movement. The grab bucket is installed at the head of the trunk beam via a wire rope. The input boom pitch angle N is mapped to the luffing amplitude x, and its kinematic model is expressed as follows: ;

[0144] The third-order nonlinear transformation is as follows:

[0145] ;

[0146] ;

[0147] ;

[0148] Among them, symbols Indicates the angle correction operator. Based on the initial parameters such as L0~L5, B, C, F0, and P in the four-bar gantry crane, the angles A0~A9 of each hinge point can be calculated, thus realizing the nonlinear solution of the amplitude variation.

[0149] Based on the above forward kinematics model, the inverse kinematics model with amplitude x as input and pitch angle N as output is established as follows:

[0150] ;

[0151] This problem is equivalent to solving a nonlinear equation:

[0152] ;

[0153] Using the Brent method, the row interval can be... Iterative solution:

[0154] ;

[0155] in This represents a hybrid iterative operator that combines the bisection method, the secant method, and inverse quadratic interpolation, with the convergence condition being: .

[0156] S2.2.2: Using the boom's pitch angle (i.e., the angle between the boom and the horizontal plane) and the planned linear velocity of the grab bucket, the rotational speed of the second motor driving the luffing motion is calculated through the speed transmission model.

[0157] The velocity transfer model is represented as:

[0158] ;

[0159] in, To control the rotational speed of the second motor driving the luffing motion, Let be the linear velocity at time t. and These are two velocity transfer coefficients related to the forward kinematics model.

[0160] S2.2.3: Based on the relationship between motor speed and frequency, the speed of the second motor is converted into the control frequency of the second motor.

[0161] ;

[0162] in, , and These are the reduction ratio, slip, and number of pole pairs of the second motor, respectively.

[0163] In some other embodiments, the remote control method further includes:

[0164] III. Stable Stop-Self-Start Mechanism.

[0165] To accurately transmit the planned anti-sway trajectory for rotation and amplitude to the PLC for real-time trajectory tracking and precise anti-sway control, rotation-frequency and amplitude-frequency mapping tables are established respectively. The frequency mapping tables are optimized by removing duplicate displacements and taking the smaller frequency.

[0166] As shown in Figure 4, a design-based steady-stop-self-starting anti-disturbance logic is introduced to achieve smooth braking of the grab bucket when a disturbance is triggered, and automatic re-planning of the trajectory to the target point after the disturbance disappears.

[0167] S3.1: During the rotation and / or luffing operation of the gantry crane controlled by the first motor control frequency and / or the second motor control frequency, disturbances are monitored in real time, and when disturbances are detected, the angular velocity and / or linear velocity are reduced by gradient deceleration until the grab bucket comes to a complete stop.

[0168] Disturbances such as collision warnings, manual interruptions, and gradient deceleration and disturbance monitoring methods can refer to existing technologies.

[0169] S3.2: After the grab bucket comes to a complete stop, continuously monitor the disturbance, and after the disturbance disappears, re-plan the grab bucket rotation and / or luffing to regain the control frequency of the first motor and / or the control frequency of the second motor until the grab bucket reaches the target position.

[0170] That is, steps S1 and S2 are repeated to regain the control frequency of the first motor and / or the control frequency of the second motor. A stable stop-start mechanism is introduced, adding a flexible response strategy to external warning signals, thereby preventing the grab bucket from violently swinging due to inertial overshoot during forced shutdown, and simultaneously enabling automatic recovery.

[0171] In some other embodiments, the remote control method further includes:

[0172] IV. Real-time location feedback correction

[0173] As shown in Figure 5, dynamic trajectory correction is performed to reduce the deviation between the actual path and the planned path during actual anti-sway control.

[0174] Specifically, the position of the grab bucket is acquired in real time; based on the planned position and the real-time position of the grab bucket, the luffing position deviation and / or rotational position deviation of the grab bucket are calculated.

[0175] Determine whether the amplitude position deviation and / or rotation position deviation are greater than the corresponding set threshold. If so, maintain the currently planned first motor control frequency and / or second motor control frequency. Otherwise, obtain the frequency reduction coefficient under the current deviation and use the obtained frequency reduction coefficient K to correct the first motor control frequency and / or second motor control frequency until the target position is reached.

[0176] ;

[0177] in, For the corrected first motor control frequency and / or second motor control frequency, This refers to the control frequency of the first motor and / or the control frequency of the second motor before correction. The frequency reduction factor under the current deviation is obtained by using the pre-set relationship between the position deviation and the frequency reduction factor.

[0178] Example 2

[0179] As shown in Figure 6, an adaptive parameter tuning anti-sway control system for a gantry crane grab bucket includes:

[0180] The control layer is used to issue the first motor control frequency and / or the second motor control frequency;

[0181] The execution layer is used to control the gantry crane to perform rotation and / or luffing movements;

[0182] The perception layer is used to collect the amplitude of the grab bucket and the rotation angle of the target in real time under the current working conditions.

[0183] The control layer includes:

[0184] The rotational motion control module is used to obtain the control frequency of the first motor. Specifically, it constructs a variable amplitude distance factor and a rotation angle factor, and after weighted fusion of the variable amplitude distance factor and the rotation angle factor, dynamically corrects the maximum angular velocity under the current working condition; based on the corrected maximum angular velocity, it uses the S-curve trajectory planning method to plan the rotation of the grab bucket, and converts the angular velocity of the rotation plan into the control frequency of the first motor.

[0185] The luffing motion control module is used to obtain the control frequency of the second motor. Specifically, it obtains the maximum linear velocity of the grab based on the target luffing amplitude and uses the S-curve trajectory planning method to plan the luffing amplitude of the grab. Based on the target luffing amplitude, it obtains the pitch angle of the boom using the inverse kinematic relationship between the boom and the grab, and nonlinearly maps the pitch angle of the boom and the planned linear velocity of the grab to the control frequency of the second motor that drives the luffing motion through the velocity transfer model.

[0186] The perception layer is responsible for real-time acquisition of multi-source heterogeneous data. It uses high-precision positioning sensors such as QR code cameras, inclinometers, and rotary encoders to collect grab bucket position-related data and transmit it to the control layer.

[0187] The control layer consists of an industrial computer and a PLC. The industrial computer, as the decision-making core, deploys the anti-sway control algorithm. By analyzing key parameters such as rotation angle and luffing radius transmitted from the sensing layer in real time, it completes the anti-sway trajectory planning of the grab bucket and generates collaborative control commands. It also has the functions of data storage, fault diagnosis, and communication with other systems. The PLC, as the core control device, receives the positioning data of the rotation mechanism and luffing mechanism fed back from the sensing layer to capture the precise position of the grab bucket and sends it to the anti-sway algorithm. At the same time, it converts the command results calculated by the anti-sway control algorithm into specific control signals and sends them to the execution layer.

[0188] The execution layer, based on instructions from the control layer, controls the rotation and luffing movements of the gantry crane via a drive frequency converter, achieving precise movement of the grab bucket. Real-time data transmission and interaction between different layers are achieved through communication methods such as industrial Ethernet and CAN bus, ensuring coordinated system operation. Absolute encoders are installed on the luffing and rotation mechanisms respectively to measure the luffing and rotation angles; an inclinometer is installed at the boom root to assist in detecting the luffing angle and verifying the absolute encoder values. Combined with the boom length and angle, the required amplitude data for luffing positioning is calculated and transmitted to the control layer. QR code stickers are affixed at equal intervals to the large gear ring of the drum, and a QR code camera is installed on the drum extension bracket to assist in verifying the rotation angle. The rotation angle calculation data is then transmitted to the control layer.

[0189] In some other embodiments, as shown in Figure 7, the control layer is refined into an edge controller, a trajectory planner, and an anti-sway controller. First, the host computer reads the precise position of the current mechanism through the edge controller. The trajectory planner calculates the S-shaped trajectory for anti-swaying of the amplitude and rotation mechanism based on the position information. It uses a frequency conversion model to convert speed into mechanism control frequency signal and sends the position-frequency mapping table to the anti-sway controller. The anti-sway controller quickly finds the control frequency based on the position information reported by the edge controller and performs secondary compensation based on the frequency compensator before sending it to the PLC to realize anti-swaying of the frequency drive control mechanism.

[0190] Example 3

[0191] The present invention provides a computer device, including a processor and a memory; wherein, when the processor executes the computer program stored in the memory, it implements the steps of the above-mentioned adaptive parameter tuning method for the anti-sway control of the grab bucket of a gantry crane.

[0192] For more detailed information on the above methods, please refer to the relevant content disclosed in the foregoing embodiments, which will not be repeated here.

[0193] Example 4

[0194] The present invention provides a computer-readable storage medium for storing a computer program; when the computer program is executed by a processor, it implements the steps of the above-described adaptive parameter tuning method for the anti-sway control of a gantry crane grab bucket.

[0195] For more detailed information on the above methods, please refer to the relevant content disclosed in the foregoing embodiments, which will not be repeated here.

[0196] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. The systems, devices, and storage media disclosed in the embodiments are described simply because they correspond to the methods disclosed in the embodiments; relevant details can be found in the method section.

[0197] Those skilled in the art will clearly understand that the techniques in the embodiments of the present invention can be implemented using software plus necessary general-purpose hardware platforms. Based on this understanding, the technical solutions in the embodiments of the present invention, or the parts that contribute to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in various embodiments or certain parts of the embodiments of the present invention.

[0198] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of the present invention should be considered within the scope of protection of the present invention.

Claims

1. A method for anti-sway control of a grab bucket of a gantry crane with adaptive parameter tuning, characterized in that, include: The gantry crane is controlled to perform rotation and / or luffing movements using a first motor control frequency and / or a second motor control frequency. The first motor control frequency is used to drive the grab bucket's rotational movement. The first motor control frequency is obtained by: real-time acquisition of the grab bucket's luffing amplitude and target rotation angle under the current working condition, constructing a luffing distance factor and a rotation angle factor, and then dynamically correcting the maximum angular velocity under the current working condition after weighted fusion of the luffing distance factor and rotation angle factor; based on the corrected maximum angular velocity, the grab bucket's rotation is planned using an S-curve trajectory planning method, and the angular velocity of the rotation planning is converted into the first motor control frequency. The second motor control frequency is used to drive the grab bucket's luffing movement. The second motor control frequency is obtained by: obtaining the grab bucket's maximum linear velocity based on the target luffing amplitude, and using an S-curve trajectory planning method for grab bucket luffing planning; based on the target luffing amplitude, the boom's pitch angle is obtained using the inverse kinematic relationship between the boom and the grab bucket, and the boom's pitch angle and the planned linear velocity of the grab bucket are nonlinearly mapped to the second motor control frequency through a velocity transfer model.

2. The adaptive parameter tuning method for anti-sway control of a gantry crane grab bucket according to claim 1, characterized in that, The amplitude distance factor for: ;in, This refers to the luffing range of the grab bucket under current operating conditions. and These are the maximum and minimum amplitude limits for the amplitude-changing mechanism; the rotation angle factor... for: ;in, The reference angle scaling factor is k, and the curve steepness coefficient is k. The target rotation angle is used as the basis; after weighting and fusing the amplitude distance factor and the rotation angle factor, a comprehensive influence factor is obtained. ： ;in, The angle weighting factor; the dynamic correction of the maximum angular velocity under the current working condition specifically involves: ;in, The maximum angular velocity under the current operating condition after dynamic correction. This represents the initial maximum angular velocity.

3. The adaptive parameter tuning method for anti-sway control of a gantry crane grab bucket according to claim 1, characterized in that, The grab rotation planning, based on the corrected maximum angular velocity and using the S-curve trajectory planning method, specifically involves: correcting the angle according to the target. and the maximum angular velocity after dynamic correction Calculate the total motion time of the grab bucket rotation. Based on the total motion time of the grab bucket rotation, the S-curve trajectory planning method is used to plan the grab bucket rotation, and the angular velocity of the grab bucket rotation plan is obtained. and rotation trajectory; ;in, This is the time gain coefficient used to adjust the total rotation time to adapt to changing operating conditions.

4. The adaptive parameter tuning method for anti-sway control of a gantry crane grab bucket according to claim 1, characterized in that, The maximum linear velocity of the grab is obtained based on the target amplitude of the grab, and the S-curve trajectory planning method is used for grab amplitude planning. Specifically, the maximum linear velocity of the grab is calculated. ； ;in, and These are the maximum and minimum limiting linear velocities of the grab bucket's end motion, respectively. This is the curve steepness coefficient. The target amplitude of the grab bucket, To smooth the midpoint; calculate the total motion time of the grab bucket's luffing. ； ;in, This is the time gain coefficient used to adjust the total luffing time to adapt to changing operating conditions; based on the total motion time of the grab bucket luffing. The S-curve trajectory planning method is used to plan the luffing of the grab bucket, and the linear velocity and luffing trajectory of the luffing plan are obtained.

5. The adaptive parameter tuning method for anti-sway control of a gantry crane grab bucket according to claim 1, characterized in that, The method involves using inverse kinematics to solve for the boom's pitch angle based on the target amplitude, and then using the boom's pitch angle and the planned linear velocity of the grab bucket to nonlinearly map the velocity transfer model to the control frequency of the second motor. Specifically, based on the geometric constraints of the boom and grab bucket, a forward kinematic model is established to calculate the amplitude using the pitch angle. Then, based on this forward kinematic model, the inverse kinematic relationship is solved, and the amplitude is used to calculate the control frequency of the second motor. Solve for the boom's pitch angle. ； Using the boom's pitch angle and the planned linear velocity of the grab, the rotational speed of the second motor driving the luffing motion is calculated through a speed transmission model. Based on the relationship between motor speed and frequency, the second motor's speed is converted into its control frequency. The speed transmission model is expressed as follows: ;in, To control the rotational speed of the second motor driving the luffing motion, Let be the linear velocity at time t. and These are two velocity transfer coefficients related to the forward kinematics model.

6. The adaptive parameter tuning method for anti-sway control of a gantry crane grab bucket according to claim 1, characterized in that, During the process of controlling the gantry crane to rotate and / or luffing using the control frequency of the first motor and / or the control frequency of the second motor, disturbances are monitored in real time. When a disturbance is detected, the angular velocity and / or linear velocity are reduced by a gradient deceleration method until the grab bucket comes to a complete stop. After the grab bucket comes to a complete stop, disturbances are continuously monitored. After the disturbances disappear, the grab bucket rotation planning and / or luffing planning are re-performed to regain the control frequency of the first motor and / or the control frequency of the second motor until the grab bucket reaches the target position.

7. The adaptive parameter tuning method for anti-sway control of a gantry crane grab bucket according to claim 1, characterized in that, During the process of controlling the gantry crane to perform rotation and / or luffing movements using the first motor control frequency and / or the second motor control frequency, the position of the grab bucket is acquired in real time. Based on the planned position and the real-time position of the grab bucket, the luffing position deviation and / or rotation position deviation of the grab bucket are calculated. It is determined whether the luffing position deviation and / or rotation position deviation are greater than the corresponding set threshold. If so, the current planned first motor control frequency and / or second motor control frequency are maintained. Otherwise, the frequency reduction coefficient under the current deviation is obtained by using the pre-set relationship between the position deviation and the frequency reduction coefficient. The obtained frequency reduction coefficient K is used to correct the first motor control frequency and / or second motor control frequency until the target position is reached. ;in, For the corrected first motor control frequency and / or second motor control frequency, The first motor control frequency and / or the second motor control frequency before correction.

8. An adaptive parameter tuning anti-sway control system for a gantry crane grab bucket, characterized in that, include: The control layer is used to issue the control frequency of the first motor and / or the control frequency of the second motor; the execution layer is used to control the gantry crane to perform rotation and / or luffing movements. The perception layer is used to collect the luffing amplitude and target rotation angle of the grab bucket under the current working condition in real time. The control layer includes: a rotation motion control module, used to obtain the control frequency of the first motor, specifically: constructing a luffing distance factor and a rotation angle factor, and after weighted fusion of the luffing distance factor and the rotation angle factor, dynamically correcting the maximum angular velocity under the current working condition; based on the corrected maximum angular velocity, using the S-curve trajectory planning method to plan the rotation of the grab bucket, and converting the angular velocity of the rotation planning into the first motor control frequency; and a luffing motion control module, used to obtain the control frequency of the second motor, specifically: obtaining the maximum linear velocity of the grab bucket based on the target luffing amplitude, and using the S-curve trajectory planning method to plan the luffing amplitude of the grab bucket; based on the target luffing amplitude, using the inverse kinematic relationship between the boom and the grab bucket to obtain the pitch angle of the boom, and nonlinearly mapping the pitch angle of the boom and the planned linear velocity of the grab bucket into the second motor control frequency through a velocity transfer model.

9. A computer device, characterized in that, It includes a processor and a memory; wherein, when the processor executes the computer program stored in the memory, it implements the steps of the adaptive parameter tuning anti-sway control method for the grab bucket of a gantry crane as described in any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, Used to store computer programs; when the computer programs are executed by a processor, they implement the steps of the adaptive parameter tuning anti-sway control method for gantry crane grab buckets according to any one of claims 1-7.

Images