Digital control method for multi-machine cooperative hoisting of movable arm type tower crane

Abstract

The invention discloses a digital control method for multi-machine cooperative hoisting of a movable arm type tower crane. A computer control system is used for synchronously controlling rotation and amplitude variation of two tower cranes, optimizing a motion path of a lifting hook and balancing a load. The method specifically comprises the steps that a kinematic model is established, a kinematic equation of a lifting hook and a component is established according to the position relation between the tower crane and the component, and a related equation of the horizontal rotation angular velocity and the vertical variable-amplitude angular velocity of a large arm is established; trajectory optimization control: fitting a trajectory by adopting a cubic polynomial, and iteratively solving an optimal control equation in combination with the hoisting performance parameters of the tower crane; real-time monitoring and closed-loop correction are achieved; the eccentric amplitude of the lifting hook and the load rate of the tower crane are calculated by obtaining the actual position coordinates of the lifting hook; and after the component reaches a designated position, in-place posture adjustment is achieved. According to the method, full-process digital control over cooperative hoisting of the movable arm type tower crane can be achieved, hoisting synchronization precision, load balance and construction safety are remarkably improved, manual intervention is reduced, and the method is suitable for hoisting of heavy components of super high-rise buildings.

Description

Technical Field

[0001] This invention relates to the field of building construction technology, and more specifically to a digital control method for multi-machine collaborative hoisting of luffing jib tower cranes. Background Technology

[0002] In building construction, especially in the construction of super high-rise structures, ordinary lifting machinery is insufficient to reach the corresponding lifting height. Lifting operations and vertical material transportation during construction typically rely on tower cranes, whose transportation efficiency limits the overall construction progress. Limited by the lifting capacity of tower cranes, heavy components can only be lifted in sections, which increases on-site workload and extends the overall construction period; furthermore, the quality of high-altitude operations is difficult to guarantee. For conventional lifting machinery, a dual-crane lifting operation can be chosen to increase the single-lift capacity and improve on-site construction efficiency. Tower cranes rely on the rotation of their booms to transfer objects; under manual control, it is difficult to coordinate two tower cranes to achieve the dual-crane lifting effect. Problems with synchronization can lead to serious consequences such as tower crane collisions and collapses. Summary of the Invention

[0003] This invention provides a digital control method for multi-crane collaborative lifting of luffing jib tower cranes. Through synchronous control of a computer system, it achieves high-precision collaborative operation of the rotation and boom luffing of two tower cranes, and realizes closed-loop control by monitoring the coordinates of monitoring points. This method can improve the efficiency of tower crane lifting during construction, reduce the overall construction period, and improve construction quality.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] The component to be hoisted is connected to tower cranes A and B respectively via flexible connections at both ends, allowing free rotation at the connection points. At least two measurement points are arranged on the component. The three-dimensional coordinates of these measurement points are acquired by a monitoring system. A computer control system synchronously controls the slewing and pitching of the two luffing jib tower cranes, optimizing the operating path, balancing the load rates of the two tower cranes, and achieving closed-loop control by monitoring the coordinates of the monitoring points. This ensures that the hook eccentricity and load rate of the two tower cranes remain within allowable ranges during the luffing process. The specific steps include:

[0006] S1. Establish a calculation model based on the positional relationship between the tower crane and the component, and construct the kinematic equations of the tower crane hook and the position of the component.

[0007] Horizontal angle of the two tower crane booms With upper arm pitch angle Relationship satisfies: , in This indicates the length of the two tower crane booms. L is the distance between the slewing centers of the two tower cranes, and L is the horizontal distance between the two lifting points of the lifting component.

[0008] Horizontal rotational angular velocity of the two tower crane booms Vertical luffing speed of the boom Relationship satisfies: , in Q represents the current position matrix of the tower crane hook, and Q represents the current position matrix of the component. Indicates the spin velocity of the component;

[0009] S2, with , , As a control variable, a cubic polynomial was used to fit the trajectory and establish... , , The control equations use the initial position of the tower crane hook, the target position, and the velocity as initial parameters.

[0010] S3 This represents the tower crane load factor, defining the load balance index between two tower cranes during the lifting process. Tower crane luffing speed and acceleration performance Tower crane boom luffing angle Using constraints as conditions, the objective function is solved through iterative optimization. Minimum value, obtained , , Governing equations;

[0011] S4. Solve for the trajectory of tower crane B using S1 based on the obtained control equations.

[0012] Furthermore, during the boom luffing process, the components are kept horizontal or at their initial angle by synchronously raising and lowering the hook.

[0013] Furthermore, when a luffing jib tower crane performs its boom luffing motion, the hook moves synchronously. During synchronous lifting, the hook's raising and lowering keeps the component level or at its initial angle constant. The hook compensates for the lifting distance during the lifting process. Hook retraction and extension speed .

[0014] Furthermore, the positioning posture of the component is adjusted during the hoisting process. The posture adjustment method is to keep the position of one tower crane hook stationary while controlling the raising and lowering of the hook of the other tower crane boom as it changes amplitude.

[0015] Furthermore, the angle between the component and the horizontal plane is adjusted. The relationship between the position of the tower crane and the position of the tower crane satisfies: ,

[0016] Tower crane hook retraction speed Tower crane luffing speed and satisfy: , in Adjust the speed of component attitude.

[0017] Furthermore, the tower crane boom is equipped with a first sensor and a second sensor, which are used to acquire the boom's horizontal angle and pitch angle in real time, and feed the data back to the computer control system.

[0018] Furthermore, during the hoisting process, the synchronicity of the tower crane, i.e., the eccentricity of the hook, is monitored, and an alarm is issued if the value exceeds the warning threshold. The tower crane synchronicity monitoring method involves reading the current operating information of the tower crane system or obtaining the current horizontal angle of the boom from the first and second sensors. and pitch angle Obtain the theoretical coordinates of the hook The coordinates of the measured points on the component The actual coordinates of the hook are calculated using the coordinate transformation matrix M. So, the eccentricity of the hook ,when A warning is triggered and the speed is corrected when the angle exceeds 1°.

[0019] Furthermore, the tower crane load rate is monitored during the hoisting process. The tower crane load rate monitoring method involves reading the current operating information of the tower crane system or obtaining the current hook position from a second sensor, and then interpolating the rated lifting capacity at the current position according to the lifting performance table. The theoretically shared reaction force at each lifting point is calculated based on the ratio of the distance between the lifting point and the center of gravity, thus obtaining the tower crane load factor. When the tower crane load factor... An alert is triggered when the percentage exceeds 80%.

[0020] Furthermore, it also includes displaying key information such as tower crane load rate, hook eccentricity, and current operating parameters on the control terminal to help staff understand the current working status.

[0021] A digital control method for multi-crane collaborative lifting of luffing jib tower cranes, with the following on-site operation procedure:

[0022] 1) Control the luffing of two tower cranes to connect with the lifting points respectively to the components to be lifted. Arrange two easily observable measuring points on the surface of the components and measure the initial coordinates of the hook and the measuring points to obtain the coordinate transformation matrix M between the lifting points and the measuring points;

[0023] 2) The operator inputs the tower crane position information, initial coordinates of the component lifting point, target coordinates of the component, tower crane performance table, component weight and other basic information into the control program;

[0024] 3) The program iteratively optimizes the hoisting path with the goal of balancing the loads of the two tower cranes, obtains the time history control curves of the two tower cranes, and generates the tower crane load curves during the hoisting process;

[0025] 4) Control the tower crane hook to lift synchronously to complete the removal of the tire. After the load stabilizes, lift the hook to a certain height again to ensure that there is no collision on the path during the lifting process. The height should not be too high to avoid generating large horizontal forces due to asynchronous lifting.

[0026] 5) The program controls the tower crane to start synchronous hoisting according to the time history control curve. During the hoisting process, the hook is synchronously raised and lowered to keep the horizontal angle of the component unchanged. The program displays information such as load rate, control speed, and hoisting progress on the screen. During the hoisting process, the tower crane synchronization is controlled by comparing the coordinates of the measured points on the component with the theoretical coordinates.

[0027] 6) After hoisting to the correct position, begin attitude adjustment. The program controls one tower crane to remain stationary while the other tower crane simultaneously raises and lowers its hook and adjusts its luffing to complete the attitude adjustment of the component. This process can also be performed after step 4, where the frame is removed from the mold.

[0028] 7) The hooks of the two tower cranes are lowered simultaneously to place the component in the designated position and secure it.

[0029] 8) Disconnect the tower crane from the component, and return the tower crane to its initial position to begin the next lifting operation.

[0030] In summary, the hoisting control method of the present invention can realize automatic synchronous control and process monitoring of multi-machine collaborative hoisting of luffing jib tower cranes, significantly improving hoisting synchronization accuracy, load balance and construction safety, increasing the single hoisting efficiency of tower cranes during construction, shortening the overall construction period, reducing the use of other large machinery, reducing engineering construction costs, and reducing manual intervention. It is suitable for hoisting heavy components of super high-rise buildings. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the hoisting operation.

[0032] Figure 2 This is a schematic diagram of the hoisting elevation.

[0033] Figure 3 A simplified geometric diagram;

[0034] Figure 4 This is a schematic diagram showing the location of monitoring points on the component to be hoisted.

[0035] Figure 5 This is the overall flowchart. Detailed Implementation

[0036] The following is in conjunction with the appendix Figures 1 to 5 The specific implementation method of the digital control method for multi-machine collaborative hoisting of a luffing jib tower crane of the present invention will be further described in detail.

[0037] A digital control method for dual-crane lifting of a luffing jib tower crane is disclosed. This method achieves lifting effect through coordinated control of two tower cranes, including tower crane A 101, tower crane B 102, a computer control system 103, a monitoring system 104, and the component to be lifted 105. In the following description, a plane coordinate system is established with the rotation center of tower crane A as the origin and the line connecting the rotation centers of tower crane A and tower crane B as the x-axis.

[0038] The computer control system 103 can communicate with tower crane A 101 and tower crane B 102 via wired or wireless means and control them to perform corresponding actions. It can receive the coordinates of monitoring points measured by the monitoring system 104. The two ends of the component 105 to be hoisted are connected to tower crane A and tower crane B respectively via flexible connections (steel wire ropes, etc.), and can rotate freely at the connection points. The monitoring system 104 can obtain the coordinates of the monitoring points on the component 105 to be hoisted in the plane coordinate system 111 and transmit them to the computer monitoring system 104.

[0039] Each tower crane boom is equipped with a first sensor and a second sensor, whereby the first sensor can obtain the current horizontal angle of the boom. The second sensor can acquire the boom pitch angle. .

[0040] A digital control method for dual-crane lifting with a luffing jib tower crane includes coordinated control of the luffing speed of the two tower cranes, optimization of the operating path, and balancing of the load rate of the two tower cranes. This ensures that the hook eccentricity and load rate of the two tower cranes are within the allowable range during the luffing process. The lifting process requires no manual operation. The coordinated control and load balancing steps are as follows:

[0041] S1. Establish a calculation model based on the positional relationship between the tower crane and the component, and construct the kinematic equations of the tower crane hook and the position of the component.

[0042] Horizontal angle of the two tower crane booms With upper arm pitch angle Relationship satisfies: , in This indicates the length of the two tower crane booms. L is the distance between the slewing centers of the two tower cranes, and L is the horizontal distance between the two lifting points of the lifting component.

[0043] Horizontal rotational angular velocity of the two tower crane booms Vertical luffing speed of the boom Relationship satisfies: , in Q represents the current position matrix of the tower crane hook, and Q represents the current position matrix of the component. Indicates the spin velocity of the component;

[0044] S2: According to the expression, the system has three degrees of freedom. , , As a control variable, a cubic polynomial was used to fit the trajectory and establish... , , The governing equations use the initial position and target position and velocity of the tower crane hook as initial parameters. ;

[0045] S3: This represents the tower crane load factor, defining the load balance index between two tower cranes during the lifting process. Tower crane luffing speed and acceleration performance Tower crane boom luffing angle Using constraints as conditions, the objective function is solved iteratively using an optimization algorithm. Minimum value, obtained , , Governing equations ;

[0046] S4: Solve the motion trajectory of tower crane 102 in reverse by using S1 based on the obtained control equations.

[0047] Preferably, in this embodiment, the initial angle of the component remains constant during the component hoisting process; when the boom of the luffing tower crane undergoes pitching and luffing movements, the hook moves synchronously; during synchronous hoisting, the component remains horizontal or at its initial angle constant through the synchronous lifting and lowering of the hook. The hook compensates for the lifting distance during the hoisting process. Hook retraction and extension speed .

[0048] In this preferred embodiment, the component's positioning posture is adjusted after it reaches the designated position. The posture adjustment method is as follows: while keeping one tower crane hook stationary, the other tower crane's boom is simultaneously extended and retracted while controlling the hook's raising and lowering. The component's angle relative to the horizontal plane is adjusted. The relationship between the position of the tower crane and the position of the tower crane satisfies: , Tower crane hook retraction speed Tower crane luffing speed and satisfy: , in Adjust the speed of component attitude.

[0049] In this preferred embodiment, the synchronicity (hook eccentricity) and load rate of the tower crane are monitored synchronously during the hoisting process, and an alarm is issued when the warning value is exceeded. The tower crane synchronicity monitoring method involves reading the current operating information of the tower crane system or obtaining the current horizontal angle of the boom from the first and second sensors. and pitch angle Obtain the theoretical coordinates of the hook The coordinates of the measured points on the component The actual coordinates of the hook are calculated using the coordinate transformation matrix M. So, the eccentricity of the hook ,when A warning is triggered and the speed is corrected when the angle exceeds 1°.

[0050] Tower crane load rate monitoring method: The current operating radius is obtained by reading the current operating information of the tower crane system or acquiring the current hook position from the second sensor. The rated lifting capacity at the current position is then obtained by interpolation based on the lifting performance table. The theoretically shared reaction force at each lifting point is calculated based on the ratio of the distance between the lifting point and the center of gravity. , In the formula Let G be the distance from the lifting point to the center of gravity, and G be the total weight of the component. Then the tower crane load factor is... ,when An alert is triggered when the level exceeds 80%.

[0051] In this preferred embodiment, the system also includes displaying key information such as the tower crane load rate, hook eccentricity, and a comparison of the tower crane's current operating parameters with theoretical parameters on a display terminal (computer screen) to help staff understand the current working status.

[0052] This invention provides a digital control method for dual-machine lifting of a luffing jib tower crane, and the on-site operation process is as follows:

[0053] 1) Control the luffing of two tower cranes to connect with the lifting points respectively to the components to be lifted, arrange two easily observable measuring points on the surface of the components, and measure the initial coordinates of the hook and the measuring points to obtain the coordinate transformation matrix M between the lifting points and the measuring points;

[0054] 2) The operator inputs the tower crane position information, initial coordinates of the component lifting point, target coordinates of the component, tower crane performance table, component weight and other basic information into the control program;

[0055] 3) The program iteratively optimizes the hoisting path with the goal of balancing the loads of the two tower cranes, obtains the time history control curves of the two tower cranes, and generates the tower crane load curves during the hoisting process;

[0056] 4) Control the tower crane hook to lift synchronously to complete the removal of the tire. After the load stabilizes, lift the hook to a certain height again to ensure that there is no collision on the path during the lifting process. The height should not be too high to avoid generating large horizontal forces due to asynchronous lifting.

[0057] 5) The program controls the tower crane to start synchronous hoisting according to the time history control curve. During the tower crane luffing process, the hook is raised and lowered synchronously to keep the horizontal angle of the component unchanged. The program displays information such as load rate, control speed, and hoisting progress on the screen. During the hoisting process, the tower crane synchronization is controlled by comparing the coordinates of the measured points on the component with the theoretical coordinates.

[0058] 6) After the hoisting is in place, the attitude adjustment begins. The program controls one tower crane to remain stationary while the other tower crane simultaneously raises and lowers the hook and changes the luffing to complete the attitude adjustment of the component. This process can also be carried out after step 4 is completed.

[0059] 7) The hooks of the two tower cranes are lowered simultaneously to place the component in the designated position and secure it.

[0060] 8) Disconnect the tower crane from the component, and return the tower crane to its initial position to begin the next lifting operation.

[0061] In this invention, crawler cranes or truck cranes or similar machinery can be used instead of luffing tower cranes for lifting.

[0062] The above description is merely a preferred embodiment 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 principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A digital control method for multi-machine collaborative hoisting of luffing jib tower cranes, characterized in that: The component to be hoisted is connected to tower cranes A and B respectively via flexible connections at both ends, allowing free rotation at the connection points. At least two measurement points are arranged on the component. The three-dimensional coordinates of these measurement points are acquired by a monitoring system. A computer control system synchronously controls the slewing and pitching of the two luffing jib tower cranes, optimizing the operating path, balancing the load rates of the two tower cranes, and achieving closed-loop control by monitoring the coordinates of the monitoring points. This ensures that the hook eccentricity and load rate of the two tower cranes remain within allowable ranges during the luffing process. The specific steps include: S1: Establish a calculation model based on the positional relationship between the tower crane and the component, and construct the kinematic equations of the tower crane hook and the position of the component; Horizontal angle of the two tower crane booms With upper arm pitch angle Relationship satisfies: ， in This indicates the length of the two tower crane booms. L is the distance between the slewing centers of the two tower cranes, and L is the horizontal distance between the two lifting points of the lifting component. Horizontal rotational angular velocity of the two tower crane booms Vertical luffing speed of the boom Relationship satisfies: ， in Q represents the current position matrix of the tower crane hook, and Q represents the current position matrix of the component. Indicates the spin velocity of the component; S2: with , , As a control variable, a cubic polynomial was used to fit the trajectory and establish... , , The control equations use the initial position of the tower crane hook, the target position, and the velocity as initial parameters. S3: This represents the tower crane load factor, defining the load balance index between two tower cranes during the lifting process. Tower crane luffing speed and acceleration performance Tower crane boom luffing angle To constrain the conditions, the objective function is solved through iterative optimization. Minimum value, obtained , , Governing equations; S4: Solve the motion trajectory of tower crane B through S1 based on the obtained control equations.

2. The digital control method for multi-machine collaborative hoisting of luffing jib tower cranes according to claim 1, characterized in that: During the boom luffing process, the components are kept horizontal or at their initial angle by synchronously raising and lowering the hook.

3. The digital control method for multi-machine collaborative hoisting of luffing jib tower cranes according to claim 2, characterized in that: When a luffing jib tower crane performs its boom luffing motion, the hook moves synchronously. During synchronous lifting, the hook's raising and lowering keeps the component level or at its initial angle constant, and compensates for the lifting distance during the lifting process. Hook retraction and extension speed .

4. The digital control method for multi-machine collaborative hoisting of luffing jib tower cranes according to claim 1, characterized in that: During the hoisting process, the positioning posture of the component is adjusted. The posture adjustment method is to keep the position of one tower crane hook stationary while controlling the raising and lowering of the hook of the other tower crane boom as it changes amplitude.

5. The digital control method for multi-machine collaborative hoisting of luffing jib tower cranes according to claim 4, characterized in that: The relationship between the tower crane position and the adjustment angle of the components and the horizontal plane satisfies the following: ， Tower crane hook retraction speed Tower crane luffing speed and satisfy: ， in Adjust the speed of component attitude.

6. The digital control method for multi-machine collaborative hoisting of luffing jib tower cranes according to claim 1, characterized in that: The tower crane boom is equipped with a first sensor and a second sensor, which are used to acquire the boom's horizontal angle and pitch angle in real time and feed the data back to the computer control system.

7. The digital control method for multi-machine collaborative hoisting of luffing jib tower cranes according to claim 6, characterized in that: During the hoisting process, the synchronicity of the tower crane, i.e. the eccentricity of the hook, is monitored, and an alarm is issued when the value exceeds the warning threshold. The tower crane synchronization monitoring method is to obtain the theoretical coordinates of the hook by reading the current operating information of the tower crane system or by obtaining the current angle of the boom from the first and second sensors. The actual coordinates of the hook are then calculated from the coordinates of the measurement points on the component through the coordinate transformation matrix M, thereby obtaining the eccentricity of the hook. When the eccentricity of the hook is greater than 1°, an alarm is triggered and the speed is corrected.

8. The digital control method for multi-machine collaborative hoisting of luffing jib tower cranes according to claim 6, characterized in that: During the hoisting process, the tower crane load rate is monitored. The tower crane load rate monitoring method is to read the current operating information of the tower crane system or obtain the current hook position by the second sensor, interpolate the rated lifting capacity at the current position according to the lifting performance table, and calculate the theoretical reaction force shared by each lifting point according to the ratio of the distance between the lifting point and the center of gravity, thereby obtaining the tower crane load rate. When the tower crane load rate is greater than 80%, an early warning is triggered.

9. The digital control method for multi-machine collaborative hoisting of luffing jib tower cranes according to claim 1, characterized in that: It also includes displaying key information such as tower crane load rate, hook eccentricity, and current operating parameters on the control terminal to help staff understand the current working status.

10. The digital control method for multi-machine collaborative hoisting of luffing jib tower cranes according to claim 1, characterized in that, The on-site operation procedure is as follows: 1) Control the luffing of two tower cranes to connect with the lifting points respectively to the components to be lifted, arrange two easily observable measuring points on the surface of the components, and measure the initial coordinates of the hook and the measuring points to obtain the coordinate transformation matrix M between the lifting points and the measuring points; 2) The operator inputs the tower crane position information, initial coordinates of the component lifting point, target coordinates of the component, tower crane performance table, and basic information on component weight into the control program; 3) The program iteratively optimizes the hoisting path with the goal of balancing the loads of the two tower cranes, obtains the time history control curves of the two tower cranes, and generates the tower crane load curves during the hoisting process; 4) Control the tower crane hook to lift synchronously to complete the removal of the tire. After the load stabilizes, lift the hook to a certain height again to ensure that there is no collision on the path during the lifting process. The height should not be too high to avoid generating large horizontal forces due to asynchronous lifting. 5) The program controls the tower crane to start synchronous hoisting according to the time history control curve. During the hoisting process, the hook is synchronously raised and lowered to keep the horizontal angle of the component unchanged. The load rate, control speed and hoisting progress information are displayed on the screen. During the hoisting process, the synchronization of the tower crane is controlled by comparing the coordinates of the measured points on the component with the theoretical coordinates. 6) After the hoisting is in place, the attitude adjustment begins. The program controls one tower crane to remain stationary while the other tower crane simultaneously raises and lowers its hook and changes its luffing to complete the attitude adjustment of the component. Alternatively, this process can be carried out after step 4) the removal of the mold. 7) The hooks of the two tower cranes are lowered simultaneously to place the component in the designated position and secure it. 8) Disconnect the tower crane from the component, and return the tower crane to its initial position to begin the next lifting operation.

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