Method and system for realizing active control of cargo swinging of bridge crane

Abstract

The invention relates to the technical field of crane control, in particular to a method and system for achieving active control over cargo swing of a bridge crane, and the method comprises the steps that the trolley speed, the trolley acceleration, the cart speed, the cart acceleration, the cargo mass, the trolley mass and the lifting rope length are input into a pre-established cargo swing dynamic model; the method comprises the following steps of: firstly, carrying out conversion to obtain a linearized model, then carrying out pull-type transformation on the linearized model to obtain a standard transfer function of goods in an X-axis direction, and then predicting the acceleration of a trolley at a next time node when a goods swing angle is within a swing threshold value by adopting an integrated function of a preset controller, a preset input shaper and the standard transfer function. And finally, a driving instruction for predicting acceleration motion is sent to the trolley. Compared with the prior art, the method can effectively restrain goods from swinging in the process that the trolley carries the goods to move.

Description

Technical Field

[0001] The present invention relates to the technical field of crane control. More specifically, the present invention relates to a method and system for actively controlling the swing of goods by a bridge crane. Background Art

[0002] The support frame of a bridge crane mainly consists of steel structures such as a main girder, end beams, a carriage, and guardrails. Its driving mechanisms mainly include a trolley mechanism, a crab mechanism, and a hoisting mechanism, and the functions of grasping, lifting, unloading, and transporting goods are realized through the above three mechanisms. In order to improve the operation efficiency of the bridge crane, in actual operation, after grasping and lifting the goods, the operator usually drives the trolley and the crab to run to shorten the operation time. However, this process will not only cause the swing of the goods, but also may cause the vibration of the main girder in the plumb plane. These swings and vibrations will cause alternating loads on the crane, lead to crane fatigue, affect the safety performance of the whole machine structure, and even may cause fatigue failure of the main girder in severe cases. In addition, when the bridge crane is moving the trolley and the crab, the swing of the goods not only affects the operation efficiency, but also there are risks of accidents and damage to the goods.

[0003] Therefore, how to effectively suppress the swing of the goods during the movement of the trolley carrying the goods has become a key technical problem at present. Summary of the Invention

[0004] To solve the above technical problem of how to effectively suppress the swing of the goods during the movement of the trolley carrying the goods, the present invention provides solutions in the following aspects.

[0005] In a first aspect, the present invention discloses a method for actively controlling the swing of goods by a bridge crane, including:

[0006] Obtain the trolley speed, trolley acceleration, crab speed, crab acceleration, goods mass, trolley mass, and hoisting rope length;

[0007] Input the trolley speed, trolley acceleration, crab speed, crab acceleration, goods mass, trolley mass, and hoisting rope length into a pre-established dynamic model of goods swing, and convert to obtain a linearized model;

[0008] Perform a Laplace transform on the linearized model to obtain the standard transfer function of the goods in the X-axis direction;

[0009] Adopt a preset controller, a preset input shaper, and an integration function of the standard transfer function to predict the acceleration of the trolley at the next time node when the swing angle of the goods is within the swing threshold;

[0010] Send a driving instruction for the trolley to move with the acceleration to the trolley.

[0011] Beneficial effects: In the method of the present invention, various parameters during the operation of the bridge crane are first placed into the cargo swing dynamics model and converted into a linearized model for easy data analysis and processing. Then, the linearized model is subjected to a Laplace transform to convert the complex, multi-dimensional, and multi-directional vectors into a transfer function in the X-axis direction, so as to facilitate the control of the displacement of the trolley in the X-axis direction. Finally, an integrated function of a controller, an input shaper, and a standard transfer function is used to predict the acceleration at the next time node to maintain the cargo swing angle within the swing threshold, and then a corresponding drive command is sent to the trolley, thereby effectively suppressing the cargo swing during the movement of the trolley carrying the cargo.

[0012] Preferably, the controller adopts a PD controller, and the input shaper adopts a zero-vibration differential input shaper.

[0013] Beneficial effects: The PD controller, that is, the proportional-differential controller, wherein the differential term of the PD controller can reduce the swing amplitude and period of the cargo in the closed-loop control system, achieving the effect of suppressing the swing. The zero-vibration differential input shaper, as a feedforward controller, when combined with the PD controller, can enhance the robustness of the closed-loop control system.

[0014] Preferably, the transfer function of the zero-vibration differential input shaper is:

[0015]

[0016] In the formula, A 1 is the first pulse amplitude of the zero-vibration differential input shaper, A 2 is the second pulse amplitude of the zero-vibration differential input shaper, e is the base of the natural logarithm, s is the complex variable in the Laplace transform, and t 2 is the time-delay matrix.

[0017] Preferably, an integrated function of a preset controller, input shaper, and standard transfer function is used to predict the adjustment displacement of the trolley at the next time node when the cargo swing angle is within the swing threshold, specifically:

[0018] Integrate the PD controller, the standard transfer function, and the zero-vibration differential input shaper to obtain the displacement transfer function of the trolley;

[0019] Convert the displacement transfer function into a function of the trolley displacement in the time domain;

[0020] Calculate the second derivative of the function of the trolley displacement in the time domain as the acceleration of the trolley at the next time node when the cargo swing angle is within the swing threshold.

[0021] Beneficial effects: By integrating a PD controller, a standard transfer function, and a zero-vibration differential input shaper, the displacement transfer function of the trolley for a closed-loop control system with second-order oscillation characteristics can be obtained. To facilitate time-domain analysis and directly relate to the control requirements in the time domain, it is converted into a function of the trolley displacement in the time domain, and then the second derivative of the function of the trolley displacement in the time domain is taken to predict the acceleration at which the swinging angle of the goods is maintained within the swinging threshold. Compared with the prior art, the above technical solution is more stable and reliable.

[0022] Preferably, the displacement transfer function is:

[0023]

[0024] In the formula, X is (s) is the displacement transfer function, A i is the amplitude of the i-th pulse sequence, t i is the action time of the i-th pulse, n is the number of pulses, e is the base of the natural logarithm, k p is a parameter used to determine the undamped natural frequency in the second-order closed-loop system, k d is a parameter that forms the damping ratio in the second-order closed-loop system, s is the complex variable in the Laplace transform, and m is the total mass of the trolley and the goods.

[0025] Preferably, the function of the trolley displacement in the time domain is specifically:

[0026]

[0027] In the formula, A sys1 is the first vibration amplitude caused by the parameter k and the parameter k d , A sys2 is the second vibration amplitude caused by the parameter k and the parameter k d , is the initial vibration angle caused by the damped vibration frequency ω d , A is is the vibration amplitude caused by the input shaper, ψ is the initial vibration angle caused by the input shaper, ω n is the natural frequency, and ξ is the damping ratio.

[0028] Preferably, the linearized model is specifically:

[0029]

[0030] In the formula, when calculating the trolley and the large vehicle as a whole, m t is the mass of the trolley, m c is the mass of the goods, x is the displacement of the trolley, is the acceleration of the trolley, θ is the current angle of the goods deviating from the equilibrium point, l is the length of the lifting rope, is the lifting acceleration of the hoisting rope length, F x is the driving force acting on the trolley mechanism, and g is the acceleration due to gravity.

[0031] Beneficial effects: By the above method, the cargo swing dynamics model is linearized, the simplification of the cargo swing dynamics model is realized, the amount of data calculation is reduced, it is convenient for closed-loop feedback control, and the overall control efficiency and control effect of the closed-loop system are improved.

[0032] Preferably, the cargo swing dynamics model is specifically:

[0033]

[0034] In the formula, regarding the trolley and the crane as a whole for calculation, m t is the mass of the trolley, m c is the mass of the cargo, x is the displacement of the trolley, is the acceleration of the trolley, θ is the current angle of the cargo deviating from the equilibrium point, is the angular velocity of the cargo deviating from the equilibrium point, is the angular acceleration of the cargo deviating from the equilibrium point, l is the hoisting rope length, is the lifting speed of the hoisting rope length, is the lifting acceleration of the hoisting rope length, F x is the driving force acting on the trolley mechanism, and g is the acceleration due to gravity.

[0035] Preferably, the angular range of the swing threshold is 0° - 10°.

[0036] In the second aspect, the present invention also discloses a system for realizing the active control of the cargo swing of a bridge crane, including a processor and a memory. The memory stores computer program instructions, and when the computer program instructions are executed by the processor, the method for realizing the active control of the cargo swing of the bridge crane described in the first aspect is realized.

[0037] The beneficial effects of the present invention are as follows:

[0038] (1) Compared with the prior art, the method of the present invention first places the parameters in the operation process of the bridge crane into the cargo swing dynamics model and converts it into a linearized model for easy data analysis and processing. Then, the linearized model is subjected to a Laplace transform to convert the complex, multi-dimensional, and multi-directional vectors into a transfer function in the X-axis direction for easy control of the displacement of the trolley in the X-axis direction. Finally, an integrated function of a controller, an input shaper, and a standard transfer function is used to predict the acceleration at the next time node to maintain the cargo swing angle within the swing threshold, and then a corresponding drive instruction is sent to the trolley, thereby effectively suppressing the cargo swing during the movement of the trolley carrying the cargo.

[0039] (2) Compared with the prior art, the operation amount of the method of the present invention is less, which is convenient for closed-loop feedback control, and the control response speed is shorter.

[0040] (3) Compared with the prior art, the control of the trolley for suppressing the swing of the goods by the method of the present invention is more stable and reliable. Description of the Drawings

[0041] By reading the following detailed description with reference to the accompanying drawings, the above and other objects, features and advantages of the exemplary embodiments of the present invention will become readily understood. In the drawings, several embodiments of the present invention are shown in an exemplary rather than restrictive manner, and the same or corresponding reference numerals denote the same or corresponding parts, wherein:

[0042] Figure 1 is a flowchart of a method for actively controlling the swing of goods by a bridge crane in the first embodiment of the present invention;

[0043] Figure 2 is a Cartesian coordinate system construction diagram of a method for actively controlling the swing of goods by a bridge crane in the first embodiment of the present invention;

[0044] Figure 3 is a structural connection diagram of a system for actively controlling the swing of goods by a bridge crane in the second embodiment of the present invention;

[0045] Figure 4 is a structural block diagram of a system for actively controlling the swing of goods by a bridge crane in the third embodiment of the present invention. Detailed Embodiments

[0046] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0047] This embodiment discloses a method and a system for actively controlling the swing of goods by a bridge crane, which are used to effectively suppress the swing of goods during the movement of the trolley carrying the goods. The following will describe the specific embodiments of the present invention in detail with reference to the accompanying drawings.

[0048] Embodiment 1

[0049] As Figure 1 shown, this embodiment discloses a method for actively controlling the swing of goods by a bridge crane, including:

[0050] S10: Obtain the speed of the trolley, the acceleration of the trolley, the speed of the large vehicle, the acceleration of the large vehicle, the mass of the goods, the mass of the trolley, and the length of the lifting rope.

[0051] S20: Input the speed of the trolley, the acceleration of the trolley, the speed of the large vehicle, the acceleration of the large vehicle, the mass of the goods, the mass of the trolley, and the length of the lifting rope into the pre-established dynamic model of the swinging goods, and convert it to a linearized model.

[0052] S30: Perform a Laplace transform on the linearized model to obtain the standard transfer function of the goods in the X-axis direction.

[0053] S40: Use the integration function of the preset controller, the preset input shaper, and the standard transfer function to predict the acceleration of the trolley at the next time node when the swinging angle of the goods is within the swinging threshold.

[0054] S50: Send a driving instruction for the trolley to move with the acceleration.

[0055] Through the above steps S10 - S50, the method of the present invention first inputs the speed of the trolley, the acceleration of the trolley, the speed of the large vehicle, the acceleration of the large vehicle, the mass of the goods, the mass of the trolley, and the length of the lifting rope obtained in real time into the dynamic model of the swinging goods, then performs linear simplification to obtain a linearized model, then converts the linearized model into a standard transfer function, and integrates the preset controller, the preset input shaper, and the standard transfer function, and uses the integrated function to predict the acceleration of the trolley at the next time node when the swinging angle of the goods is within the swinging threshold, so as to drive the trolley to execute the action at the next time node with the predicted acceleration. Compared with the prior art, the method of the present invention can stably and quickly suppress the swinging of the goods.

[0056] As Figure 2 shown, in this embodiment, in order to establish the dynamic model of the swinging goods, it is necessary to simplify the operating mechanism of the tower crane. The following specifically explains the specific process of obtaining the linearized model through simplification:

[0057] (1) First establish a Cartesian coordinate system

[0058] First, regard the metal structure of the tower crane as a rigid body, and simplify the operating mechanism into a large vehicle and a trolley - wire rope - goods system. Take a certain section of the large vehicle as the coordinate origin, the extension line of the large vehicle as the x-axis, and the vertical direction as the y-axis to establish a Cartesian coordinate. The coordinate origin of the inertial Cartesian coordinate system o 1 is taken at one end of the bridge, and the coordinate origin o 2 of the non-inertial polar coordinate system is taken at the suspension point of the hoisting wire rope and moves with the trolley mechanism. Among them, x is the displacement of the large vehicle and the trolley (hereinafter referred to as the trolley), l is the length of the hoisting wire rope, θ is the angle between the wire rope and the vertical direction, m c is the mass of the goods, m tis the mass of the trolley (considering the large vehicle and the trolley as a whole).

[0059] (2) Establish a dynamic model of the cargo swing

[0060] According to the Cartesian coordinate system constructed above, the corresponding Lagrangian function is derived. Assuming the potential energy is 0 at y = 0, the Lagrangian function of the crane system is as follows:

[0061]

[0062] where, K c is the kinetic energy of the cargo, K t is the kinetic energy of the trolley, V c is the potential energy of the cargo, g is the acceleration due to gravity, generally taken as 9.8 m / s 2 .

[0063] Differentiating the above Lagrangian function, we can obtain:

[0064]

[0065] where, F x is the driving force for the movement of the large vehicle and the trolley, F l is the driving force for the hoisting movement. After the above differentiation and simplification, the dynamic model of the cargo swing for the tower crane moving the large vehicle, the trolley, and hoisting simultaneously can be obtained:

[0066]

[0067] In the formula, considering the trolley and the large vehicle as a whole, m t is the mass of the trolley, m c is the mass of the cargo, x is the displacement of the trolley, is the acceleration of the trolley, θ is the current angle of the cargo deviating from the equilibrium point, is the angular velocity of the cargo deviating from the equilibrium point, is the angular acceleration of the cargo deviating from the equilibrium point, l is the length of the hoisting rope, is the lifting speed of the hoisting rope, is the lifting acceleration of the hoisting rope, F x is the driving force acting on the trolley mechanism, g is the acceleration due to gravity.

[0068] Furthermore, the linearized model obtained in the above step S20 is specifically as follows:

[0069] At the equilibrium position of the cargo θ ∈ [0°, 10°], linearize the above dynamic model of the cargo swing.

[0070] It should be noted that the angular range of the equilibrium position of the goods is extremely small. Therefore, sinθ≈θ and cosθ≈1 can be obtained by simplification. At the same time, the high-order terms of the above-mentioned dynamic model of the goods swing are ignored, and only the first-order terms are retained, then the linearized model can be obtained:

[0071]

[0072] Furthermore, ignoring air resistance and only considering the horizontal movement of the trolley mechanism in the x direction, the above linearized model can finally be simplified to:

[0073]

[0074] where, regarding the trolley and the large vehicle as a whole for calculation, m t is the mass of the trolley, m c is the mass of the goods, x is the displacement of the trolley, is the acceleration of the trolley, θ is the current angle of the goods deviating from the equilibrium point, l is the length of the lifting rope, is the acceleration of the lifting rope length, F x is the driving force acting on the trolley mechanism, and g is the acceleration due to gravity.

[0075] Compared with the prior art, the method of the present invention calculates by taking key elements in the dynamic model of the goods swing, ignores the secondary elements that have little influence on the goods swing, realizes the simplification of the dynamic model of the goods swing, reduces the amount of calculation, and can improve the operation efficiency of the method of the present invention.

[0076] Correspondingly, the process of calculating the transfer function of the bridge crane under the operating conditions of the large vehicle and the trolley is as follows:

[0077]

[0078] In the formula, G p (s) is the linearized model of the bridge crane during the movement of the trolley. The typical input signal is a class of standard input patterns that have been widely studied and verified, and can be used to represent the statistical characteristics and dynamic characteristics of the actual input signal. Its common step input is:

[0079]

[0080] In the above step S30, the linearized model is subjected to Laplace transform to obtain the standard transfer function of the goods in the X-axis direction, specifically:

[0081]

[0082] where, G(s) is the standard transfer function, g is the acceleration due to gravity, ω n is the natural frequency of the goods swing, ξ is the cargo swing damping ratio, i is the number of damped waves.

[0083] Preferably, the controller in the above step S40 adopts a PD controller. According to the transfer function of the PD controller and the above standard transfer function, the transfer function of the PD feedback control system can be obtained as follows:

[0084]

[0085] It should be explained that the PD controller changes the natural frequency of the cargo swing from ω n becomes ω N , the damping ratio changes from ξ to ξ N Among them, ω N and N The expression is:

[0086]

[0087] In actual work, the length of the hoisting wire rope of the tower crane will change continuously, making the natural frequency ω N and damping ratio ξ N It is also constantly changing, so a more robust input shaper is needed.

[0088] It should be explained that PD control is a closed-loop control method that performs proportional and differential transformation on the deviation ε(t). The control algorithm of the PD controller can be expressed as:

[0089]

[0090] The transfer function of the PD controller is:

[0091] H(s)=K p [1+T d s]=K p +K d s

[0092] In the formula, K p is the proportional gain, T d is the differential time constant, K d is the differential gain. This embodiment uses the proportional criticality method to determine the parameters of PD control. First, the integral and differential effects in PD control are removed, and only the proportional controller is used to control the closed-loop system. Then, a step disturbance is introduced into the system as an input signal, and the proportional gain K is gradually changed from small to large. p .

[0093] In this embodiment, the input shaper in the above step S40 adopts a zero-vibration differential input shaper, and its transfer function is:

[0094]

[0095] In the formula, A 1 is the first pulse amplitude of the zero-vibration differential input shaper, A 2 is the second pulse amplitude of the zero-vibration differential input shaper, e is the base of the natural logarithm, s is the complex variable in the Laplace transform, and t 2 is the time-delay matrix.

[0096] The method of the present invention reduces the dynamic model of the swing of the goods of the tower crane to a second-order oscillation model. Therefore, to eliminate the vibration of the second-order oscillation system using the ZV input shaper, it is necessary to make the vibrations generated by each pulse signal cancel each other out after the end of the pulse sequence generated by the input shaper.

[0097] After making the above-mentioned vibrations cancel each other out, the pulse amplitudes A i and the time-delay t i of the two-pulse ZV input shaper can be solved respectively as follows:

[0098]

[0099] where K is a parameter, T is the half vibration period of the system,

[0100] The specific parameters of the PD combined input shaping controller are determined according to the actual working parameters of the tower crane. Among them, the proportional gain of the PD controller is K p = 10, and the derivative gain is K d = 3; the pulse amplitudes A i and the time-delay t i of the ZV input shaper are respectively as follows:

[0101]

[0102] Further, the specific step S40 is as follows:

[0103] S41: Integrate the PD controller, the standard transfer function, and the zero-vibration differential input shaper to obtain the displacement transfer function of the trolley.

[0104] S42: Convert the displacement transfer function into a function of the trolley displacement in the time domain.

[0105] S43: Calculate the second derivative of the function of the trolley displacement in the time domain as the acceleration of the trolley at the next time node when the swing angle of the goods is within the swing threshold.

[0106] More specifically, the displacement transfer function of the trolley is:

[0107]

[0108] Among them, X is (s) is the displacement transfer function, A i is the amplitude of the i-th pulse sequence, t i is the action time of the i-th pulse, n is the number of pulses, e is the base of the natural logarithm, k p is the parameter used to determine the undamped natural frequency in the second-order closed-loop system, k d is the parameter that forms the damping ratio in the second-order closed-loop system, s is the complex variable in the Laplace transform, and m is the total mass of the trolley and the goods.

[0109] It should be noted that under the control of the PD controller combined with the input shaper, the displacement of the trolley mechanism consists of two parts, and its general expression is:

[0110] x is (t) = x is1 (t) + x is2 (t)

[0111] Among them, x is1 (t) is the forced displacement, x is2 (t) is the free displacement. According to the above displacement transfer function of the trolley, the inverse Laplace transform of the general expression of the displacement of the trolley mechanism under PD feedback control can be performed to obtain the expression of the displacement of the trolley mechanism under PD feedback control in the time domain:

[0112]

[0113] Performing the inverse Laplace transform on the displacement formula of the trolley mechanism under PD combined with input shaping control again, the function of the trolley displacement in the time domain under PD combined with input shaping control is obtained, specifically:

[0114]

[0115] In the formula, A sys1 is the first vibration amplitude caused by the parameter k and the parameter k d , A sys2 is the second vibration amplitude caused by the parameter k and the parameter k d , is the initial vibration angle caused by the damped vibration frequency ω d , A is is the vibration amplitude caused by the input shaper, and ψ is the initial vibration angle caused by the input shaper.

[0116] In this embodiment, the specific calculation formula of A sys1 is:

[0117] A sys1 = kk d a0 / m(ξ n ω n 2 +ω d 2 )

[0118] In this embodiment, A sys2 The specific calculation formula is:

[0119] A sys2 = kk d [(a 0 -ξ n ω n ) 2 +ω d 2 1 / 2 / mω d (ξ n ω n 2 +ω d ) 1 / 2

[0120] In this embodiment, The specific calculation formula is:

[0121]

[0122] In this embodiment, A is The specific calculation formula is:

[0123]

[0124] In this embodiment, the specific calculation formula of ψ is:

[0125]

[0126] In this embodiment, ω d The calculation formula is:

[0127]

[0128] In step S40, through the operation of the function of the above-mentioned trolley displacement in the time domain, the displacement of the trolley at the next time node when the swing angle of the goods is within the swing threshold can be accurately obtained, and then the displacement function is second-order differentiated to obtain a more accurate acceleration.

[0129] Furthermore, this embodiment also introduces an output shaper, and the composition of its pulse signal, and the specific transfer function is:

[0130]

[0131] In the formula, n is the number of pulses, A​i is the amplitude of the i-th pulse, and t i is the time when the i-th pulse occurs. s is to make the designed input shaper have good performance indicators. A i and t i need to satisfy the following constraints respectively:

[0132]

[0133] In order to effectively eliminate the residual vibration of the system, it is necessary to make the residual vibration of the system zero after the pulse sequence generated by the input shaper ends. The residual vibration is defined as the ratio of the amplitude of the unit impulse response of the system under the control of the input shaper to the amplitude of the unit impulse response of the system without input shaping control. Its formula is:

[0134]

[0135] In the formula, ω n is the natural frequency of the system, and ξ is the damping ratio of the system. And there is:

[0136]

[0137] Let the residual vibration be equal to zero, that is:

[0138]

[0139] Through the design and function integration of the input shaper, controller, output shaper and linearization model in the active control system of the bridge crane in this embodiment, the active control system of the bridge crane forms a stable, reliable second-order closed-loop control system with a very small swing angle of the goods.

[0140] Embodiment 2

[0141] As Figure 3 shown, this embodiment discloses a system for suppressing the swing of goods when the trolley and the crab of the crane move, including a laser rangefinder, a three-dimensional inclinometer, a host computer system, a central control system, a coordinate calculation subsystem at the trolley suspension point, an ideal acceleration calculation subsystem, a trolley servo drive subsystem and a trolley servo drive subsystem.

[0142] The laser rangefinder is installed on the end beam of the bridge crane and is used to measure the displacement and speed of the trolley in real time.

[0143] The three-dimensional inclinometer is horizontally installed on the hook and is used to measure the swing angle of the goods in real time.

[0144] The host computer system is used to store and output the displacement, speed and acceleration data related to the lifting weight, the movement of the trolley and the crab.

[0145] The main functions of the central control system include: collecting and integrating data from various sensors and subsystems. Based on the calculation results and control algorithms, control instructions are issued to various actuators. The central control system receives the following input data: data from sensors such as laser rangefinders and inclinometers; output data from the ideal acceleration calculation subsystem, the trolley suspension point coordinate calculation subsystem, etc.; commands entered through the control panel or remote control device. The central control system generates precise control instructions by comprehensively processing various sensor data and subsystem outputs, converting and transmitting the real-time speed and acceleration data of the trolley output by the laser rangefinder to the coordinate calculation subsystem at the trolley suspension point. In addition, the central control system also transmits the lifting capacity, displacement, speed and acceleration data of the trolley and trolley provided by the host system to the ideal acceleration calculation subsystem, and transmits the data generated by the ideal acceleration calculation subsystem to the trolley servo drive subsystem.

[0146] The coordinate calculation subsystem at the trolley suspension point is responsible for calculating the three-dimensional coordinate position of the trolley suspension point in space according to the motion state and posture of the crane. It receives real-time data from the crane host system, including the swing angle and the distance between the trolley and the trolley. Based on the kinematic model and posture parameters of the crane, the coordinate position of the cargo in space is calculated using geometric and mathematical methods. The position of the cargo in the fuselage coordinate system is converted to the inertial coordinate system to obtain its absolute coordinate position in space. According to the real-time input data, the coordinate position of the trolley suspension point is continuously updated to adapt to the movement changes of the crane. This subsystem transmits the calculated trolley suspension point coordinate data to the central control system to monitor and control the movement of the crane. The coordinate calculation subsystem at the trolley suspension point calculates the coordinate position of the trolley suspension point in space through the kinematic model and real-time data, providing important information for the motion control and monitoring of the crane.

[0147] The ideal acceleration calculation subsystem receives the crane state parameters (such as lifting weight, rope length, displacement, speed, acceleration of the trolley and the small car, etc.) and the real-time swing angle of the cargo in the vertical plane from the central control system. According to the crane state parameters and the swing angle of the cargo, the ideal driving acceleration of the cargo in the vertical plane is calculated using the corresponding algorithm. This acceleration is designed to compensate or offset the swing of the cargo so that the cargo can remain stable. The ideal acceleration calculation subsystem transmits the calculated ideal driving acceleration data to the small car servo drive subsystem to further control the motion state of the small car.

[0148] The trolley servo drive subsystem is responsible for adjusting the motion state of the trolley according to the input control signal to suppress the swing of the goods. It receives the real-time drive acceleration data from the ideal acceleration calculation subsystem, as well as the position coordinates and real-time dynamic data of the trolley in the vertical plane provided by the central control system. It generates a control signal according to the calculation result to adjust the output of the trolley drive motor, so that the trolley runs along a predetermined trajectory, thereby reducing or eliminating the swing of the goods. This subsystem also feeds back the real-time displacement data of the trolley to the central control system for further adjustment and control. Through complex calculations and precise control, the trolley servo drive subsystem effectively regulates the motion state of the trolley to ensure that the swing of the goods is suppressed when the crane moves in the cross-travel and trolley motions.

[0149] Embodiment 3

[0150] As Figure 3 shown, on the basis of Embodiment 1, this embodiment also discloses a system for actively controlling the swing of goods of a bridge crane. The system includes a processor and a memory. The memory stores computer program instructions, which implement the method for actively controlling the swing of goods of a bridge crane described in Embodiment 1 when the computer program instructions are executed by the processor.

[0151] In the present invention, the foregoing memory can be any tangible medium that contains or stores a program, and this program can be used by or in combination with an instruction execution system, apparatus, or device. For example, the computer-readable storage medium can be any suitable magnetic storage medium or magneto-optical storage medium, such as resistive random access memory (RRAM), dynamic random access memory (DRAM), static random access memory (SRAM), enhanced dynamic random access memory (EDRAM), high-bandwidth memory (HBM), hybrid memory cube (HMC), etc., or any other medium that can be used to store the required information and can be accessed by an application program, module, or both. Any such computer storage medium can be part of the device or accessible or connectable to the device. Any application or module described in the present invention can be implemented using computer-readable / executable instructions that can be stored or otherwise held by such a computer-readable medium.

[0152] In the description of this specification, "a plurality of" means at least two, such as two, three, or more, etc., unless otherwise specifically defined.

[0153] Although this specification has shown and described multiple embodiments of the present invention, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Those skilled in the art will think of many changes, alterations, and alternative ways without departing from the spirit and scope of the present invention. It should be understood that various alternatives to the embodiments of the present invention described herein may be employed in practicing the present invention.

Claims

1. A method for realizing active control of cargo swing of a bridge crane, characterized in that: include: Obtain the trolley speed, trolley acceleration, truck speed, truck acceleration, cargo mass, trolley mass and lifting rope length; Inputting the trolley speed, the trolley acceleration, the truck speed, the truck acceleration, the cargo mass, the trolley mass and the lifting rope length into a pre-established cargo pendulum dynamics model, and converting to obtain a linearized model; Performing a pull-type transformation on the linearized model to obtain a standard transfer function of the cargo in the X-axis direction; Using a preset controller, a preset input shaper and an integration function of the standard transfer function, the acceleration of the trolley at the next time node when the cargo swing angle is within the swing threshold is predicted; A driving instruction is issued to the trolley to move at the acceleration.

2. The method for realizing active control of cargo swing of a bridge crane according to claim 1, characterized in that: The controller adopts a PD controller, and the input shaper adopts a zero-vibration differential input shaper.

3. The method for realizing active control of cargo swing of a bridge crane according to claim 2, characterized in that: The transfer function of the zero-vibration differential input shaper is: Wherein, A1 is the first pulse amplitude of the zero vibration differential input shaper, A2 is the second pulse amplitude of the zero vibration differential input shaper, e is the base of the natural number logarithm, s is the complex variable in the Laplace transform, and t2 is the time delay matrix.

4. The method for realizing active control of cargo swing of a bridge crane according to claim 2, characterized in that: The preset controller, input shaper and integration function of the standard transfer function are used to predict the adjustment displacement of the trolley at the next time node when the cargo swing angle is within the swing threshold, specifically: Integrate the PD controller, the standard transfer function and the zero-vibration differential input shaper to obtain a displacement transfer function of the vehicle; Converting the displacement transfer function into a function of the vehicle displacement in the time domain; The second-order derivative of the function of the trolley displacement in the time domain is calculated as the acceleration of the trolley at the next time node when the cargo swing angle is within the swing threshold.

5. The method for realizing active control of cargo swing of a bridge crane according to claim 4, characterized in that: The displacement transfer function is: Where, X is (s) is the displacement transfer function, A i is the amplitude of the ith pulse train, t i is the action time of the ith pulse, n is the number of pulses, e is the base of the natural number logarithm, k p is the parameter used to determine the undamped natural frequency of the second-order closed-loop system, k d is the parameter that forms the damping ratio in the second-order closed-loop system, s is the complex variable in the Laplace transform, and m is the total mass of the cart and the cargo.

6. The method for realizing active control of cargo swing of a bridge crane according to claim 5, characterized in that: The function of the car displacement in the time domain is specifically: In the formula, A sys1 is composed of parameters k and k d The first vibration amplitude caused, A sys2 is composed of parameters k and k d The second vibration amplitude caused by is the damped vibration frequency ω d The initial angle of the induced vibration, A is is the vibration amplitude caused by the input shaper, ψ is the initial angle of vibration caused by the input shaper, ω n is the natural frequency and ξ is the damping ratio.

7. The method for realizing active control of cargo swing of a bridge crane according to claim 1, characterized in that: The linearized model is specifically: In the formula, the small car and the large car are considered as a whole, m t is the mass of the trolley, m c is the mass of the cargo, x is the displacement of the trolley, is the acceleration of the trolley, θ is the current angle of the cargo away from the equilibrium point, l is the length of the lifting rope, is the lifting acceleration of the lifting rope, F x is the driving force acting on the trolley mechanism, and g is the acceleration due to gravity.

8. The method for realizing active control of cargo swing of a bridge crane according to claim 1, characterized in that: The cargo pendulum dynamics model is specifically: In the formula, the small car and the large car are considered as a whole, m t is the mass of the trolley, m c is the mass of the cargo, x is the displacement of the trolley, is the acceleration of the trolley, θ is the current angle of the cargo away from the equilibrium point, is the angular velocity of the cargo deviating from the equilibrium point, is the angular acceleration of the cargo deviating from the equilibrium point, l is the length of the lifting rope, i is the lifting speed of the lifting rope, is the lifting acceleration of the lifting rope, F x is the driving force acting on the trolley mechanism, and g is the acceleration due to gravity.

9. The method for realizing active control of cargo swing of a bridge crane according to claim 1, characterized in that: The angle range of the swing threshold is 0°-10°.

10. A system for realizing active control of cargo swing of a bridge crane, characterized in that: It comprises a processor and a memory, wherein the memory stores computer program instructions, and when the computer program instructions are executed by the processor, a method for actively controlling the swing of cargo by a bridge crane according to any one of claims 1-9 is implemented.

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