Three-dimensional path planning and tracking control system and method for tower crane lifting hook

Abstract

The invention discloses a three-dimensional path planning and tracking control system of a tower crane lifting hook, which is formed by interconnecting four functional modules, namely a tower crane running state detection module, a tower crane dynamic performance detection module, a lifting hook three-dimensional path planning module and a lifting hook path tracking control module, the tower crane running state detection module provides data support for the tower crane dynamic performance detection module and the lifting hook three-dimensional path planning module, and the tower crane running state detection module, the tower crane dynamic performance detection module and the lifting hook three-dimensional path planning module jointly provide data support for the lifting hook path tracking control module. The invention further discloses a three-dimensional path planning and tracking control method of the tower crane lifting hook. The invention belongs to the technical field of tower crane intelligent control, solves the problems of high construction site environment modeling cost, insufficient real-time performance and stable control of the tower crane in a large inertia state, and improves the working efficiency of the tower crane.

Description

Technical Field

[0001] The invention belongs to the technical field of tower crane hook tracking control, and relates to a three-dimensional path planning and tracking control system for a tower crane hook. The invention also relates to a three-dimensional path planning and tracking control method for a tower crane hook. Background Art

[0002] Tower cranes, hereinafter referred to as tower cranes, are important vertical transportation tools in the construction industry. Due to high-altitude operations, small space and inconvenient movement, the working environment of tower crane drivers is very bad. Long-term intense work greatly affects the driver's mood, making tower crane drivers have greater human safety hazards at work. With the development of communication technology and video technology, in order to reduce construction labor costs, unmanned control of tower cranes has become a research hotspot in the past two years.

[0003] Construction scene perception and modeling are the prerequisites for unmanned tower crane driving. On the one hand, due to the large working range of the tower crane, the environmental modeling of the tower crane working scene needs to use laser radar, which is costly. In addition, the construction site changes dynamically, and the real-time performance of dynamic map construction using laser radar cannot meet the on-site requirements. On the other hand, during the operation of the tower crane, the path of the hook is a three-dimensional spatial path. The existing three-dimensional automatic path tracking control method has high algorithm complexity and high requirements on model accuracy. However, due to the various working conditions of the tower crane, such as different loads and different external wind speeds, the dynamic performance of the tower crane will be affected. At the same time, the tower crane has a relatively large inertia. In the path tracking control, it is necessary to ensure a smooth transition of the motion state to avoid hard impact on the steel structure of the tower crane.

[0004] Therefore, the existing spatial three-dimensional path tracking algorithm is difficult to ensure the smooth movement of the tower crane and the reliability of tracking. It is urgent to develop a new method to overcome the above technical problems. Summary of the invention

[0005] The purpose of the present invention is to provide a three-dimensional path planning and tracking control system for a tower crane hook. On the one hand, it solves the problems of difficulty in modeling complex construction site environments, high cost of automatic path planning and insufficient real-time performance; on the other hand, it solves the problem of insufficient stability of the automatic driving of tower cranes in the prior art and the hard impact on the steel structure of the tower crane.

[0006] Another object of the present invention is to provide a three-dimensional path planning and tracking control method for a tower crane hook, which solves the problems of high cost, insufficient real-time performance and insufficient stability of automatic path planning in the prior art.

[0007] The technical solution adopted by the present invention is that the three-dimensional path planning and tracking control system of the tower crane hook is composed of four interconnected functional modules, namely, a tower crane operation status detection module, a tower crane dynamics performance detection module, a hook three-dimensional path planning module, and a hook path tracking control module. The tower crane operation status detection module provides data support for the tower crane dynamics performance detection module and the hook three-dimensional path planning module, and the tower crane operation status detection module, the tower crane dynamics performance detection module, and the hook three-dimensional path planning module jointly provide data support to the hook path tracking control module.

[0008] Another technical solution adopted by the present invention is a three-dimensional path planning and tracking control method for a tower crane hook, which relies on the above-mentioned three-dimensional path planning and tracking control system for a tower crane hook, and the implementation process is as follows:

[0009] The tower crane driver performs an actual lifting operation, and the tower crane operation status detection module uses three sensors to obtain the position information of the hook in real time;

[0010] The tower crane dynamics performance detection module uses the hook position information to detect the dynamics performance of the tower crane's three-dimensional motion and obtain the speed control thresholds for rotation, luffing, and hook lifting.

[0011] The hook three-dimensional path planning module uses the three-dimensional coordinate values ​​of the hook to record the three-dimensional coordinates of all points in the storage path and complete the path planning of the hook between two points;

[0012] The hook path tracking control module uses the tower crane's dynamic performance parameters and the three-dimensional coordinates of all hooks on the path, and sends control instructions to the tower crane's electrical control system according to the hook path tracking process to complete the hook path tracking control.

[0013] The beneficial effects of the present invention are that the tower crane driver controls the tower crane to complete a lifting operation between two points through an operating handle, thereby realizing manual planning of the path of the hook. On this basis, a hook path tracking process is designed in combination with the dynamic characteristics of the tower crane, thereby realizing three-dimensional automatic path tracking of the hook in the reciprocating motion between position A (loading point) and position B (unloading point) of the tower crane. Specifically: (1) According to the working characteristics of the tower crane at the construction site, the driver manually completes the three-dimensional path planning between the two points, thereby solving the problems of high cost and insufficient real-time performance of the construction site environment modeling; (2) The dynamics-based three-dimensional path tracking process of the hook is adopted to realize unmanned control of the reciprocating motion of the two points of the tower crane, thereby solving the problem of stable control of the tower crane in a large inertia state, and the tracking position error is small, thereby improving the working efficiency of the tower crane. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 is a diagram showing the relationship between the tower crane movement and the hook position in the method of the present invention;

[0015] Figure 2It is the process of detecting the dynamic characteristics of the slewing motion of the tower crane in the method of the present invention;

[0016] Figure 3 It is the process of detecting the dynamic characteristics of the luffing motion of the tower crane trolley in the method of the present invention;

[0017] Figure 4 It is the process of detecting the dynamic characteristics of the lifting motion of the tower crane hook in the method of the present invention;

[0018] Figure 5 It is a schematic diagram of tower crane path planning in the method of the present invention;

[0019] Figure 6 The method of the present invention is a tower crane hook path tracking control process based on dynamic characteristics;

[0020] Figure 7 It is a functional module relationship block diagram adopted by the method of the present invention;

[0021] Figure 8 is the planned path of the tower crane hook from position A to position B in embodiment 1 of the method of the present invention;

[0022] Fig. 9 It is the method embodiment 1 of the present invention, using tracking control mode 1, the tracking path of the hook from position A to position B;

[0023] Fig.10 This is the method embodiment 2 of the present invention, using tracking control mode 2, the tracking path of the hook from position B to position A;

[0024] Fig.11 This is the method embodiment 3 of the present invention, using tracking control mode 1, and planning the path of the hook from position A to position B;

[0025] Fig.12 This is Example 4 of the method of the present invention, which adopts tracking control mode 2 and tracks the path of the hook from position B to position A. DETAILED DESCRIPTION

[0026] The method of the present invention is described in detail below with reference to the accompanying drawings and specific implementations.

[0027] The design idea of ​​the present invention is to guide the tower crane hook to perform a lifting operation between two points through manual operation by the tower crane driver, complete the path planning of the tower crane hook between the two points, and on this basis, design the hook path tracking control method based on the dynamic characteristics of the tower crane to realize unmanned control of the round trip between two points in a complex environment of hook movement, ensure the stability of the tower crane movement, and improve the working efficiency of the tower crane.

[0028] Reference Figure 7The three-dimensional path planning and tracking control system of the tower crane hook of the present invention is composed of four interconnected functional modules, namely, a tower crane operation status detection module, a tower crane dynamics performance detection module, a hook three-dimensional path planning module, and a hook path tracking control module. The tower crane operation status detection module provides data support for the tower crane dynamics performance detection module and the hook three-dimensional path planning module. The tower crane operation status detection module, the tower crane dynamics performance detection module, and the hook three-dimensional path planning module jointly provide data support for the hook path tracking control module. The four functional modules are respectively described as follows.

[0029] A. Tower crane operation status detection module.

[0030] According to the working principle of the tower crane, the tower crane controls the three-dimensional movement of the crane arm rotation, the trolley luffing and the hook lifting, and controls the operating position of the hook in three-dimensional space to complete the safe lifting of materials.

[0031] Reference Figure 1 The construction method of the tower crane operation status detection module is to establish a three-dimensional coordinate system O-XYZ with the center O of the tower crane standard section as the origin, where XOY is called the ground two-dimensional coordinate system, and the tower crane rotation angle θ t is the angle between the vertical projection of the boom and the X-axis, and the trolley amplitude r t is the distance between the luffing trolley and the center of the tower crane (origin O), and the hook height h t is the height of the hook relative to the ground;

[0032] According to the tower crane rotation angle θ t 、Trolley amplitude r t And the hook height h t , the current three-dimensional spatial position D(θ t , r t ,h t ), thus, the data collection method of the tower crane operation status detection module is to install a height sensor, a position sensor and an angle sensor on the tower crane to realize the current position D (θ t , r t ,h t ) real-time monitoring and data collection, and complete storage.

[0033] B. Tower crane dynamic performance detection module.

[0034] According to the working principle of the tower crane, the control of the three-dimensional movement of the tower crane's boom rotation, trolley amplitude change and hook lifting all adopts variable frequency speed control. Due to the large inertia of the tower crane and the slow response of the movement speed, if the tower crane speed changes too quickly, it will cause a rigid impact on the structure of the tower crane or cause unstable movement. Therefore, the tower crane movement speed adopts a step-by-step speed control mode, and its speed gear adjustment needs to be based on the dynamic performance of the tower crane. Considering that the dynamic performance of the three-dimensional movement of the tower crane is different, and different movements have different effects on the tower crane, before the tower crane movement speed is controlled in steps, the dynamic performance of different movements of the tower crane needs to be tested first.

[0035] B1) Dynamic performance test of tower crane rotation motion.

[0036] The influence of the dynamic performance of the tower crane's rotational motion is mainly manifested in that when the tower crane is rotating, if the boom's rotational motion is suddenly started and stopped, the inertia of the boom will have an impact on the tower crane's steel structure.

[0037] The angular velocity of the tower crane arm rotation motion is set to three gears, namely ω θi , i = 1, 2, 3, where ω θ3 As the highest gear, at the same time, the counterclockwise rotational movement is determined as the positive direction and the counterclockwise rotational movement is determined as the negative direction.

[0038] Reference Figure 2 , the detection process of the dynamic characteristics of the tower crane's rotary motion is as follows:

[0039] B1.1) Confirm that the tower crane is under rated load;

[0040] B1.2) The tower crane runs at the highest speed ω θ3 Smooth rotation;

[0041] B1.3) Use the tower crane operation status detection module to obtain the rotation angle θ of the tower crane boom in real time t ;

[0042] B1.4) Tower crane boom at angle θ 0 The tower crane boom continues to rotate due to inertia until the boom reaches the angle θ. 1 Stop exercising;

[0043] B1.5) Calculate the maximum rotation speed ω θ3 Angle of inertia: θ=|θ 1 -θ 0 |; Define the maximum rotation speed ω at this inertia angle θ position θ3 The corresponding rotation speed control threshold θ 3 ;

[0044] According to the above process, the tower crane rotation speed ω is obtained θ2The corresponding rotation speed control threshold θ 2 , get the tower crane rotation speed ω θ1 The corresponding rotation speed control threshold θ 1 .

[0045] B2) Dynamic performance test of tower crane trolley’s boom movement.

[0046] The impact of the dynamic performance of the tower crane trolley's luffing motion is mainly manifested in that the load under the tower crane's steel rope will swing when the tower crane trolley's luffing motion stops suddenly, resulting in unstable load motion. In order to reduce the load swing, according to the tower crane frequency conversion control principle, the inverter parameter "acceleration and deceleration time" can be adjusted to adjust the slope of the inverter frequency change, so that the trolley's luffing speed change has a buffer process, thereby reducing the load swing caused by the trolley's luffing motion.

[0047] The tower crane trolley luffing motion is set to three gears, namely v ri , i=1,2,3, and v r3 as the highest gear; at the same time, the outward amplitude change direction of the trolley is determined as the positive direction, and the inward amplitude change direction of the trolley is determined as the negative direction.

[0048] Reference Figure 3 , the detection process of the dynamic characteristics of the trolley's variable amplitude motion is as follows:

[0049] B2.1) Confirm that the trolley is under rated load;

[0050] B2.2) Adjust the "acceleration and deceleration time" parameters of the trolley variable frequency drive;

[0051] B2.3) The trolley moves at the maximum amplitude change speed v r3 Smooth movement;

[0052] B2.4) Use the tower crane operation status detection module to obtain the trolley amplitude r in real time t ;

[0053] B2.5) The car has an amplitude of r 0 When the car stops suddenly, the speed v r3 During the process of descending to a stop, the car will continue to move with an amplitude of r 1 Stop the movement when the load inertia is reached; in this process, the load will swing due to inertia. If the load swings greatly in the air, return to step B2.2) and adjust the "acceleration and deceleration time" parameters of the inverter; if the load swings slightly, confirm that the "acceleration and deceleration time" parameters of the inverter are reasonable and execute step B2.6);

[0054] B2.6) Calculate the maximum amplitude change speed v of the trolley r3 Movement distance: r = | r 1 -r0 |; Define the moving distance r as the maximum speed v of the car r3 The corresponding amplitude speed control threshold r 3 ;

[0055] According to the above process, detect the trolley amplitude change speed v r2 The amplitude speed control threshold r 2 , detect the trolley amplitude change speed v r1 The amplitude speed control threshold r 1 ;

[0056] B3) Dynamic performance test of tower crane hook lifting movement.

[0057] The impact of the tower crane hook lifting motion dynamics performance is mainly manifested in the tower crane hook lifting motion mutation, due to the load inertia will cause the tower crane boom to vibrate in the vertical direction. In order to reduce the vibration of the boom, according to the tower crane frequency conversion control principle, the inverter parameter "acceleration and deceleration time" can be adjusted to adjust the slope of the inverter frequency change, so that the hook lifting speed change has a buffer process, thereby reducing the boom vibration caused by the hook lifting motion.

[0058] The speed of the tower crane's hook lifting movement is set to five gears, namely v hi , i = 1, 2, 3, 4, 5, where v h5 As the highest gear, the upward movement direction of the hook is determined as the positive direction, and the downward movement direction of the hook is determined as the negative direction.

[0059] Reference Figure 4 The detection process of the dynamic characteristics of the tower crane hook lifting motion is as follows:

[0060] B3.1) Confirm that the hook is under rated load;

[0061] B3.2) The hook stops at a height of h 0 Location;

[0062] B3.3) Adjust the "acceleration and deceleration time" parameters of the hook lifting inverter;

[0063] B3.4) Use the tower crane operation status detection module to obtain the hook height h in real time t ;

[0064] B3.5) The hook is at a height of h 0 position, suddenly at the highest lifting speed v h5 Start the hook to move upward, and the hook speed increases from 0 to v h5 , the hook height reaches h 1During this process, if the boom swings greatly, return to step B3.2) and adjust the "acceleration and deceleration time" parameters of the lifting inverter; if the boom swings slightly, confirm that the inverter parameters are reasonable and execute step B3.6);

[0065] B3.6) Calculate the maximum lifting speed v of the hook h5 Movement distance: h=|h 1 -h 0 |; Define the movement distance h as the maximum speed v of the hook lifting movement h5 The corresponding hook lifting speed control threshold h 5 ;

[0066] According to the above method, the lifting speed v of the tower crane hook is detected respectively. h4 ,v h3 ,v h2 ,v h1 The corresponding hook lifting speed control threshold h 4 、h 3 、h 2 and h 1 .

[0067] C. Hook three-dimensional path planning module.

[0068] When the tower crane needs to lift materials back and forth between position A and position B for multiple times, the tower crane driver controls the three-dimensional movements of the tower crane boom rotation, trolley luffing and hook lifting through the handle according to the driving experience and environmental conditions. The tower crane completes a complete lifting process of the hook from position A to position B in the optimal path recognized by the tower crane driver.

[0069] In this process, the hook forms a three-dimensional path in space. The tower crane operation status detection module collects the tower crane operation status data in real time through three related sensors (i.e., height sensor, position sensor, and angle sensor), and records the continuous position of the hook during the operation of the tower crane in real time. i (θ i ,r i ,h i ), so as to plan the three-dimensional path of the tower crane hook between position A and position B; at the same time, considering the particularity of the tower crane's rotation movement, in the manual planning process of the path, the direction of the tower crane's rotation movement is recorded, and the tower crane's rotation movement direction variable is set as F θ , then when the tower crane rotates counterclockwise, F θ =1, when the tower crane rotates clockwise F θ =0;

[0070] A material transport by a tower crane includes three stages: lifting, smooth movement and hook dropping. The lifting stage is the lifting movement of the hook, and the hook is at a high altitude off the ground; the smooth movement stage generally refers to the hook being lifted off the ground, and depending on the target position, the tower crane boom is rotated, the trolley is variable, and the hook is lifted in three dimensions to reach the position above the target; the hook dropping stage is the downward movement of the tower crane hook, and the hook reaches the height of the unloading area.

[0071] Reference Figure 5 , Figure 5 The dotted line in the figure is the operation path of the tower crane actively controlled by the driver, which is the three-dimensional planning path of the hook space formed from position A to position B. Position A→position C1 is the lifting stage; position C1→position C2 is the stable movement stage; position C2→position B is the hook drop stage; Figure 5 Point p in 1 ,p 2 ,p 3 ,…,p i ,...,p n are all specific location points recorded in the path planning, as shown in Table 1, which shows the three-dimensional coordinates of each specific location point in the planned path; at the same time, the tower crane rotation direction variable F is determined θ =1.

[0072] Table 1. p of each position point collected by the hook three-dimensional path planning module n (θ n ,r n ,h n )

[0073]

[0074] D. Hook path tracking control module.

[0075] After the three-dimensional path planning module of the hook is constructed, the hook path tracking control module determines the forward tracking point through the real-time detection of the hook's operating status and the planned path, calculates the position error (including angle error, amplitude error and height error), and plans the three-dimensional movement direction and speed gear of the hook based on the dynamic performance of the hook's three-dimensional motion and the motion control method based on the dynamic characteristics of the tower crane. The motion control signal is output to the tower crane electrical control system (this is the control system that comes with the tower crane). The tower crane electrical control system then specifically controls the tower crane's boom rotation, trolley amplitude change and hook lifting, thereby realizing the three-dimensional path tracking motion of the tower crane hook under unmanned control.

[0076] In the method of the present invention, the hook path tracking control module actually includes two modes, one is the tracking control output of the hook from position A→position B, called path tracking control mode 1; the second is the tracking control output of the hook from position B→position A, called path tracking control mode 2. The paths of the two modes are the same but the directions of movement are opposite. The two working modes are implemented separately in combination with the direction instructions (positive or negative) of the relevant actions.

[0077] Reference Figure 6 , the process of the hook path tracking control module of the present invention is as follows:

[0078] Step 1: Initialize each module;

[0079] 1.1) Start the tower crane operation status detection module and the hook path tracking control module, and at the same time, start the communication between the hook path tracking control module and the tower crane electrical control system;

[0080] 1.2) The hook path tracking control module reads the parameters set by the hook 3D path planning module, including: 3D path position point p n (θ n , r n ,h n ) data, the total number of tracking points in the planned path is n;

[0081] 1.3) The hook path tracking control module reads the dynamic performance parameters of the tower crane's three-dimensional motion obtained by the tower crane dynamic performance detection module, including: the rotation speed control threshold θ 1 ,θ 2 ,θ 3 , amplitude speed control threshold r 1 、r 2 、r 3 , hook lifting speed control threshold h 1 、h 2 、h 3 、h 4 、h 5 ;

[0082] 1.4) Set the hook path tracking spatial position error ε in the hook path tracking control module and update the foresight distance S of the tracking point dl .

[0083] Step 2: Determine the path tracking control mode;

[0084] The hook path tracking control module obtains the current position D(θ t , r t ,h t ), calculate the current position and the p of the three-dimensional path planning 1 Spatial distance of points |Dp 1|, and the current position and p n Spatial distance of points |Dp 2 |;

[0085] If |Dp 1 |<|Dp 2 |, it is determined to belong to path tracking control mode 1, and the tracking target point is set to p n ; Otherwise, it is determined to belong to path tracking control mode 2, and the tracking target point is set to p 1 .

[0086] Step 3: Get the current position of the hook;

[0087] The hook 3D path planning module uses three sensors installed on the tower crane to obtain the 3D coordinate value D (θ t , r t ,h t ).

[0088] Step 4: Calculate the position deviation of the hook's three-dimensional path tracking;

[0089] Let P k (θ k , r k ,h k ) is the three-dimensional coordinate of the current tracking point. In the process of hook path tracking control, the position deviation between the current position of the tower crane hook and the current tracking point is set as: angle deviation Δθ, amplitude deviation Δr and height deviation Δh, expressed as follows:

[0090] Δθ=θ k -θ t ,

[0091] Δr=r k -r t ,

[0092] Δh=h k -h t .

[0093] Step 5: 3D path tracking control planning of tower crane hook based on dynamics;

[0094] The tower crane path tracking control planning is to determine the current angular velocity ω of the rotary motion θ , the trolley variable amplitude motion speed v r , hook lifting speed v h ; At the same time, add a positive or negative sign prefix in front of each speed value to clarify the positive and negative directions of three-dimensional motion. The specific instructions are as follows:

[0095] 5.1) The slewing motion planning of the tower crane boom is set as follows:

[0096] The angular velocity of the tower crane boom rotation motion is set to three gears, denoted as ω θi , i = 1, 2, 3, where ω θ3 As the highest gear; during the path tracking process, the direction of the slewing motion of the tower crane arm is determined by the variable F recorded during the path planning process. θ It is confirmed that there are several situations for the angular velocity gear setting of rotary motion:

[0097] If |Δθ|<θ 1 , set the current rotational motion angular velocity ω θ =0;

[0098] If θ 1 <|Δθ|<θ 2 , set the current rotational motion angular velocity ω θ =ω θ1 ;

[0099] If θ 2 <|Δθ|<θ 3 , set the current rotational motion angular velocity ω θ =ω θ2 ;

[0100] If θ 3 <|Δθ|, set the current rotation angular velocity ω θ =ω θ3 ;

[0101] Among them, θ 1 ,θ 2 ,θ 3 The rotation speed control thresholds correspond to the three rotation motion angular velocity gears respectively.

[0102] 5.2) The tower crane trolley luffing motion planning is set as follows:

[0103] The tower crane trolley variable amplitude motion is set to three gears, which are denoted as v ri , i = 1, 2, 3, where v r3 As the highest gear, if the amplitude deviation Δr>0, the tower crane trolley changes its amplitude outward and the movement speed is positive; otherwise, the trolley changes its amplitude inward and the movement speed is negative;

[0104] If Δr≤r 1 , set the current trolley variable amplitude motion speed v r =0, the trolley’s luffing motion stops;

[0105] If r 1 <Δr≤r 2 , set the current trolley variable amplitude motion speed v r =v r1 ;

[0106] If r 2 <Δr≤r 3 , set the current trolley variable amplitude motion speed v r =v r2 ;

[0107] If r 3 <Δr, set the current trolley variable amplitude motion speed v r =v r3 ;

[0108] Among them, r 1 、r 2 、r 3 It is the amplitude deviation threshold value corresponding to the speed gear of the tower crane trolley variable speed movement.

[0109] 5.3) The lifting motion planning of the tower crane hook is set as follows:

[0110] The speed of the hook lifting movement is set to five gears, which are denoted by v hi , i = 1, 2, 3, 4, 5, where v h5 As the highest gear; if the height deviation Δh>0, the tower crane will lift the hook upwards, and the lifting speed of the hook will be positive; otherwise, the tower crane will drop the hook downwards, and the lifting speed of the hook will be negative;

[0111] If h 5 <|Δh|, set the current hook lifting speed v h =V h5 ;

[0112] If h 4 <|Δh| <h 5 , set the current hook lifting speed v h =V h4 ;

[0113] If h 3 <|Δh| <h 4 , set the current hook lifting speed v h =V h3 ;

[0114] If h 2 <|Δh| <h 3 , set the current hook lifting speed v h =V h2 ;

[0115] If h 1 <|Δh| <h 2 , set the current hook lifting speed v h =V h1 ;

[0116] If |Δh| <h 1 , hook lifting speed v h =0;

[0117] Among them, h 1 、h 2 、h 3 、h 4 、h 5 It is the height deviation threshold value corresponding to the lifting speed gear of the tower crane.

[0118] Step 6: Hook tracking control output;

[0119] The hook path tracking control module sends the tower crane movement speed and direction instructions planned in step 5 to the tower crane electrical control system, and the tower crane electrical control system then controls the relevant drive equipment of the tower crane's three-dimensional movement to accurately complete the three-dimensional movement states of the boom rotation, trolley amplitude change and hook lifting.

[0120] Step 7: Update the points to be tracked;

[0121] Considering the large inertia of the tower crane, in order to ensure the smoothness of the hook path tracking movement, the tower crane updates the point to be tracked using a larger foresight distance S dl to determine; Figure 5 In the planning path shown by the dotted line, the two points marked with “×” are respectively called the current tracking point and the point to be tracked.

[0122] Assume that the total number of path points recorded during the planning path (dashed line) is n, and the coordinates of the current position of the hook are D(θ t , r t ,h t ), the current tracking point is p k (θ k , r k ,h k ), then the update method of the point to be tracked is as follows:

[0123] 7.1) In path tracking control mode 1, if the current tracking point p k (θ k , r k ,h k ) is the path tracking target point p n (θ n , r n ,h n ), then the point to be tracked is still p n (θ n , r n ,h n ); otherwise, calculate the point p separately k+1 (θ k+1, r k+1 ,h k+1 ), …, p n (θ n , r n ,h n ) and the current position of the hook D(θ t , r t ,h t ) i (i=k+1,…n), the distance calculation formula is as follows:

[0124]

[0125] The distance S i Center and front sight distance S dl The distance point with the smallest error is identified as the point to be tracked;

[0126] 7.2) In path tracking control mode 2, if the current tracking point p k (θ k , r k ,h k ) is the path tracking target point p 1 (θ 1 , r 1 ,h 1 ), then the point to be tracked is still p 1 (θ 1 , r 1 ,h 1 ); otherwise, calculate the point p separately k-1 (θ k-1 , r k-1 ,h k-1 ), …, p 1 (θ 1 , r 1 ,h n ) and the current position of the hook D(θ t , r t ,h t ) i (i=1, ...k-1), the distance calculation formula is as follows:

[0127]

[0128] Step 8: Determine whether the path tracking is completed;

[0129] Calculate the current position D(θ t , r t ,h t ) and the spatial distance DP of the path tracking target point,

[0130] The current state is path tracking mode 1, and the spatial distance DP expression is:

[0131]

[0132] The current state is path tracking mode 2, and the spatial distance DP expression is:

[0133]

[0134] If |DP|<ε, ε is the error value, it means that the hook has reached the target position, the path tracking is completed, and the hook path tracking control process is exited;

[0135] Otherwise, return to step 3 to continue tracking.

[0136] Reference Figure 7 The three-dimensional path planning and tracking control method of the tower crane hook of the present invention relies on the processes of the above four functional modules, namely, the tower crane operation status detection module, the tower crane dynamic performance detection module, the hook three-dimensional path planning module, and the hook path tracking control module.

[0137] First, the tower crane driver performs an actual lifting operation, and the hook travels through a three-dimensional spatial path from position A to position B. The tower crane operation status detection module uses three sensors installed on the tower crane to obtain the position information of the tower crane hook in real time. Then, the tower crane operation status detection module uses this to provide historical data and real-time data for the other three functional modules.

[0138] The tower crane dynamics performance detection module uses the tower crane operation status detection module to obtain the tower crane hook position information in real time, and Figure 2 , Figure 3 as well as Figure 4 The process of detecting the dynamic performance of the tower crane's three-dimensional motion respectively obtains the performance parameter rotation speed control threshold θ 1 ,θ 2 ,θ 3 , amplitude speed control threshold r 1 、r 2 、r 3 , and the hook lifting speed control threshold h 1 、h 2 、h 3 、h 4 、h 5 ;

[0139] The hook three-dimensional path planning module uses the tower crane operation status detection module to obtain the three-dimensional coordinate value D (θ t , r t ,h t), and record the three-dimensional coordinates of all points in the storage path, so as to complete the path planning of the tower crane hook between two points;

[0140] The hook path tracking control module uses the tower crane dynamics performance parameters provided by the tower crane dynamics performance detection module and the three-dimensional coordinates of all hooks on the three-dimensional path provided by the hook three-dimensional path planning module. Figure 6 The hook path tracking process shown sends control instructions to the tower crane electrical control system to control the three-dimensional motion state of the tower crane and realize the path tracking control of the hook.

[0141] Experimental verification

[0142] A tower crane CCT331 is used at a construction site. The boom length of the tower crane is 70m. The angle sensor of the tower crane rotation, the position sensor of the trolley amplitude change and the position sensor of the hook height are installed on the tower crane to obtain the current position D(θ t , r t ,h t ).

[0143] First, according to the tower crane dynamics performance detection module of the method of the present invention, Figure 2 , Figure 3 as well as Figure 4 The process can be used to obtain the dynamic performance of the tower crane, that is, the relationship between the speed gear and the position deviation threshold of the three-dimensional motion, as shown in Table 2, Table 3, and Table 4, where the angular velocity unit is rpm, the angle unit is degree, the speed unit is m / min, and the distance unit is m.

[0144] Table 2. Tower crane boom rotation angular velocity gear and angle deviation threshold

[0145] Rotary parking Rotation 1st gear Rotation 2 gears Rotation 3 gears <![CDATA[ω θ ]]> 0 0.24 0.48 0.78 Δθ 5 30 90 >90

[0146] Table 3. Tower crane trolley amplitude change speed gear and amplitude deviation threshold

[0147] Luffing parking Amplitude adjustment 1 level 2 levels of amplitude adjustment 3 levels of amplitude adjustment <![CDATA[v r ]]> 0 6 28 55 Δr 1 6 20 >20

[0148] Table 4. Tower crane lifting speed and corresponding distance deviation threshold

[0149] Lift 1st gear Lifting 2 gears Lifting 3 gears Lifting 4 gears Lifting 5 gears <![CDATA[v h ]]> 1.5 6 30 50 70 Δh 0.2 0.4 0.6 0.8 1.0

[0150] Based on the aforementioned basic data, the method of the present invention is used to carry out specific implementation of the following embodiments.

[0151] Example 1

[0152] refer to Figure 8, the tower crane is 70 meters high. The tower crane needs to lift the steel bars from position A (30,20,0) in the ground steel bar material area to point B (-30,30,30) on the working surface of the building.

[0153] According to the aforementioned method steps, the three-dimensional path tracking control of the tower crane hook from position A to position B is completed, that is, tracking control mode 1 is adopted.

[0154] Assume the hook off the ground judgment threshold h g =5m, the starting point of the hook movement is Figure 8 According to the safety work specifications of the tower crane site, the hook path setting process is as follows: First, the hook is lifted at a low speed (from Table 3, the first gear v h =30m / min), at which time the rotary motion and amplitude variation motion stopω θ =0, v r =0; When the tower crane hook reaches a low-speed lifting height of 5 meters, the hook reaches Figure 8 Then, the crane driver controls the crane hook to move to the target position through the linkage of the crane's slewing motion, luffing motion and lifting motion according to the current position of the hook and the target position, and the hook moves to the target position when it reaches above the target position. Figure 8 Position P2 (-30,30,35) in the tower crane; finally, the tower crane drops the hook at a low speed (see Table 3, using the first gear v h =30m / min) until the hook reaches the target point. Figure 8 The position in is B(-30,30,30).

[0155] When the crane driver completes the above hook movement, the crane's operating status is detected in real time through the crane's rotation angle sensor, the trolley's amplitude position sensor, and the hook's height position sensor. The hook position is recorded according to the execution cycle of 1 second, and the three-dimensional planning path of the crane's hook from position A to position B is obtained. Figure 8 The dotted line in the figure is the planned path from position A to position B. The path records a total of 562 planned points, recording the tower crane rotation direction variable F θ =1;

[0156] according to Figure 6 As shown, the current position D(θ t , r t ,h t ) and the position error (Δθ, Δr, Δh) of the point to be tracked on the planned path, according to Figure 6 Step 5.1) and Table 1, determine the rotation speed ω θGenerally, during the hoisting process of the tower crane, the direction of the slewing motion remains unchanged. According to the slewing motion direction F recorded in the path planning θ =1, then Figure 8 The dotted line tracks the process from position A to position B, and the rotational motion is counterclockwise. Similarly, according to Figure 6 Step 5.2) and Table 2 determine the amplitude motion speed v r , according to step 5.3) and Table 3, determine the lifting speed v h , send control instructions to the tower crane electrical control system to control the three-dimensional motion state of the tower crane.

[0157] Assume that the hook tracking error is ε = 2 meters and the forward distance S dl =5 meters; press Figure 6 The hook path tracking control path shown moves from position A to position B. The tower crane hook path tracking control execution cycle is 1 second. When all 526 position points in the path are tracked and the distance between the hook position and position B at the end of the path is less than or equal to the final tracking error, the planned path tracking control is completed. Fig. 9 In the figure, the dotted line from position A to position B represents the planned path, the solid line represents the movement path of the hook from position A to position B without human operation, and the arrow on the solid line represents the direction of path tracking.

[0158] It can be seen that by adopting the method of the present invention, the maximum distance error between the actual movement path of the tower crane hook and the planned path is 3.19 meters, and the average distance error is 2.16 meters, which fully meets the requirements of the technical specifications.

[0159] Example 2

[0160] Also based on Figure 8 In the scenario, the tower crane is 70 meters high. During its operation, the tower crane travels back and forth between the ground material area position A (30,20,0) and the building working surface position B (-30,30,30) to transport steel bars.

[0161] According to the aforementioned method steps, this embodiment 2 completes the three-dimensional path tracking control of the tower crane hook from position B to position A, that is, the tracking control mode 2 is adopted, which is specifically described as follows:

[0162] like Figure 8 The dotted line in the figure is the path planning between positions A and B; Figure 6 As shown, the current position D(θ t , r t ,h t ) and the position error (Δθ, Δr, Δh) of the point to be tracked on the planned path, according to Figure 6 Step 5.1) and Table 1, determine the rotation speed ω θ, since the path planning method is opposite to the tracking direction, the rotation direction F θ = 0, reverse time rotation; similarly, according to Figure 6 Step 5.2) and Table 2 determine the amplitude motion speed v r , according to step 5.3) and Table 3, determine the lifting speed v h .

[0163] The tower crane electrical control system controls the three-dimensional motion state of the tower crane according to the control instructions. Assume that the hook tracking error is 2 meters and the forward distance is set to 5 meters; Figure 6 As shown, the tower crane hook moves from position B to position A, and the execution cycle of the path tracking control is 1 second. When all 526 position tracking points in the path are tracked, and when the distance between the hook position and the path end point A is less than or equal to the final tracking error, the path tracking control process is judged to be completed. Fig.10 In the figure, the dotted line represents the planned path between position A and position B, the solid line represents the path of the tower crane hook moving from position B to position A without human operation, and the arrow on the solid line represents the direction of path tracking.

[0164] It can be seen that, by using the method of the present invention, the maximum distance error between the actual movement path of the tower crane hook and the planned path is 3.48 meters, and the average distance error is 1.73 meters.

[0165] Example 3

[0166] Reference Fig.11 , the tower crane is 70 meters high. During the operation of the tower crane, the tower crane needs to reach the position B (-30,30,30) from the A (-20,-30,0) position.

[0167] According to the aforementioned method steps, this embodiment 3 completes the three-dimensional path tracking control of the tower crane hook from position A to position B, that is, adopts the tracking control mode 1, which is specifically described as follows:

[0168] Assume the hook off the ground judgment threshold h g =5m. According to the on-site safety work specifications of the tower crane, under the manual control of the tower crane driver, the hook completes a manually controlled lifting operation from position A to position B. During this process, the tower crane operation status detection module is used to detect the three operation status parameters of the tower crane in real time, and the position information of the hook at each tracking point is recorded to obtain the three-dimensional planning path of the hook from position A to position B.

[0169] Fig.11 The dotted line in the figure is the planned path from position A to position B. This path records a total of 562 tracking points, which record the tower crane rotation direction variable F θ =0; Fig.11The solid line in the figure is the hook tracking motion path from position A to position B, and the arrow on the solid line represents the direction of path tracking.

[0170] Depend on Fig.11 It can be seen that, by using the tower crane hook path tracking control module based on dynamic characteristics of the method of the present invention, the maximum distance error between the actual motion path of the tower crane hook and the planned path is 3.14 meters, and the average distance error is 1.91 meters.

[0171] Example 4

[0172] Also based on Fig.11 The tower crane is 70 meters high. During its operation, the tower crane needs to reach position A (-20, -30, 0) from position B (-30, 30, 30).

[0173] According to the aforementioned method steps, this embodiment 4 completes the three-dimensional path tracking control of the tower crane hook from position B to position A, that is, adopts the tracking control mode 2, which is specifically described as follows:

[0174] like Fig.12 The dotted line in the figure is the path planning between position A and position B obtained in Example 3. Figure 6 As shown, the current position D(θ t , r t ,h t ) and the position error (Δθ, Δr, Δh) of the point to be tracked on the planned path, according to Figure 6 Step 5.1) and Table 1, determine the rotation speed ω θ , since the path planning method is opposite to the tracking direction, the rotation direction F θ =1; similarly, according to Figure 6 Step 5.2) and Table 2 determine the amplitude motion speed v r , according to step 5.3) and Table 3, determine the lifting speed v h .

[0175] The tower crane electrical control system controls the three-dimensional motion state of the tower crane according to the control instructions. Assume that the hook tracking error is 2 meters and the forward distance is set to 5 meters; Figure 6 As shown, the tower crane hook moves from position B to position A, and the execution cycle of the path tracking control is 1 second. When all 526 position tracking points in the path are tracked, and when the distance between the hook position and the path end point A is less than or equal to the final tracking error, the path tracking control process is judged to be completed. Fig.12 In the figure, the dotted line represents the planned path between position A and position B, the solid line represents the path of the tower crane hook moving from position B to position A without human operation, and the arrow on the solid line represents the direction of path tracking.

[0176] It can be seen that, by using the method of the present invention, the maximum distance error between the actual movement path of the tower crane hook and the planned path is 3.43 meters, and the average distance error is 1.66 meters.

[0177] Example 5

[0178] The tower crane is 70 meters high. During the operation of the tower crane, the tower crane needs to reach the position B (-30, 30, 30) from the position A (60, 20, 0). According to the aforementioned method steps, this embodiment 5 completes the three-dimensional path tracking control of the tower crane hook from the position A to the position B, that is, the tracking control mode 1 is adopted, which is specifically described as follows:

[0179] Assume the hook off the ground judgment threshold h g =5m. According to the on-site safety work specifications of the tower crane, the hook completes a manually controlled lifting operation from position A to position B under the manual control of the tower crane driver. During this process, the three operating state parameters of the tower crane are detected in real time through the angle sensor of the tower crane's rotation state, the position sensor of the trolley's amplitude change state, and the position sensor of the hook's height state. The position information of the hook at each tracking point is recorded, and the three-dimensional path of the tower crane hook from position A to position B is planned. This path records a total of 442 tracking points, recording the tower crane's rotation direction variable F θ = 1. On this basis, the tower crane hook path tracking control module based on dynamic characteristics of the method of the present invention is adopted, and the maximum distance error between the actual motion path of the tower crane hook and the planned path is 4.39 meters, and the average distance error is 2.19 meters.

[0180] Example 6

[0181] The tower crane is 70 meters high. During the operation of the tower crane, the tower crane needs to reach the position A (60, 20, 0) from the position B (-30, 30, 30). According to the aforementioned method steps, this embodiment 6 completes the three-dimensional path tracking control of the tower crane hook from position B to position A, that is, the tracking control mode 2 is adopted, which is specifically described as follows:

[0182] Get the path planning between position A and position B obtained in implementation 5, and then according to Figure 6 As shown, the current position D(θ t , r t ,h t ) and the position error (Δθ, Δr, Δh) of the point to be tracked on the planned path, according to Figure 6 Step 5.1) and Table 1, determine the rotation speed ω θ , since the path planning method is opposite to the tracking direction, the rotation direction F θ =0; similarly, according to Figure 6 Step 5.2) and Table 2 determine the amplitude motion speed v r, according to step 5.3) and Table 3, determine the lifting speed v h .

[0183] The tower crane electrical control system controls the three-dimensional motion state of the tower crane according to the control instructions. Assume that the hook tracking error is 2 meters and the forward distance is set to 5 meters; Figure 6 As shown, the tower crane hook moves from position B to position A, and the execution cycle of the path tracking control is 1 second. When all 442 position tracking points in the path are tracked, and when the distance between the hook position and the path end point A is less than or equal to the final tracking error, the path tracking control process is judged to be completed. Using the method of the present invention, the maximum distance error between the actual movement path of the tower crane hook and the planned path is 3.76 meters, and the average distance error is 1.61 meters.

Claims

1. The three-dimensional path planning and tracking control system of the tower crane hook is characterized by: It is composed of four interconnected functional modules, namely, tower crane operation status detection module, tower crane dynamics performance detection module, hook three-dimensional path planning module, and hook path tracking control module. The tower crane operation status detection module provides data support for the tower crane dynamics performance detection module and the hook three-dimensional path planning module, and the tower crane operation status detection module, the tower crane dynamics performance detection module, and the hook three-dimensional path planning module jointly provide data support to the hook path tracking control module.

2. The three-dimensional path planning and tracking control system of a tower crane hook according to claim 1, characterized in that: The tower crane operation status detection module, The tower crane operation status detection module is constructed by establishing a three-dimensional coordinate system O-XYZ with the center O of the tower crane standard section as the origin, where XOY is called the ground two-dimensional coordinate system and the tower crane rotation angle θ t is the angle between the vertical projection of the boom and the X-axis, and the trolley amplitude r t is the distance between the luffing trolley and the center point O of the tower crane, and the hook height h t is the height of the hook relative to the ground; The data collection method of the tower crane operation status detection module is to install a height sensor, a position sensor and an angle sensor on the tower crane to realize the current position D (θ t , r t ,h t ) real-time monitoring and data collection, and complete storage.

3. The three-dimensional path planning and tracking control system of a tower crane hook according to claim 1, characterized in that: The tower crane dynamic performance detection module needs to detect the dynamic performance of different movements of the tower crane before controlling the tower crane movement speed in stages, which is divided into the following three aspects: B1) Dynamic performance test of tower crane rotation motion, The angular velocity of the tower crane arm rotation motion is set to three gears, namely ω θi , i = 1, 2, 3, where ω θ3 As the highest gear, at the same time, the counterclockwise rotation movement is determined as the positive direction, and the counterclockwise rotation movement is determined as the negative direction. The detection process of the dynamic characteristics of the tower crane's rotary motion is as follows: B1.1) Confirm that the tower crane is under rated load; B1.2) The tower crane runs at the highest speed ω θ3 Smooth rotation; B1.3) Use the tower crane operation status detection module to obtain the rotation angle θ of the tower crane boom in real time t ; B1.4) The tower crane boom suddenly stops rotating at angle θ0. Due to inertia, the tower crane boom continues to rotate until it reaches angle θ1. B1.5) Calculate the maximum rotation speed ω θ3 The inertia angle is: θ = |θ1-θ0|; the maximum rotation speed ω at the inertia angle θ is defined θ3 The corresponding rotation speed control threshold θ3; According to the above process, we can get the tower crane rotation speed ω θ2 The corresponding rotation speed control threshold θ2 is obtained to obtain the tower crane rotation speed ω θ1 The corresponding rotation speed control threshold θ1; B2) Dynamic performance test of tower crane trolley luffing motion, The tower crane trolley luffing motion is set to three gears, namely v ri , i=1,2,3, and v r3 As the highest gear; at the same time, the outward luffing direction of the trolley is determined as the positive direction, and the inward luffing direction of the trolley is determined as the negative direction. The detection process of the dynamic characteristics of the trolley's variable amplitude motion is as follows: B2.1) Confirm that the trolley is under rated load; B2.2) Adjust the "acceleration and deceleration time" parameters of the trolley variable frequency drive; B2.3) The trolley moves at the maximum amplitude change speed v r3 Smooth movement; B2.4) Use the tower crane operation status detection module to obtain the trolley amplitude r in real time t ; B2.5) The car suddenly stops at amplitude r0. The car goes from speed v r3 During the process of descending to the stop, the trolley will continue to move and stop when the amplitude is r1; during this process, due to the inertia of the load, it will swing. If the load swings greatly in the air, return to step B2.2) and adjust the "acceleration and deceleration time" parameter of the inverter; if the load swings slightly, confirm that the "acceleration and deceleration time" parameter of the inverter is reasonable and execute step B2.6); B2.6) Calculate the maximum amplitude change speed v of the trolley r3 The movement distance: r = |r1-r0|; the movement distance r is defined as the maximum amplitude change speed v of the trolley r3 The corresponding amplitude speed control threshold r3; According to the above process, the amplitude change speed control threshold r2 of the trolley amplitude change speed vr2 is detected, and the amplitude change speed v of the trolley is detected. r1 The amplitude speed control threshold r1; B3) Dynamic performance test of tower crane hook lifting motion, The speed of the tower crane's hook lifting movement is set to five gears, namely v hi , i = 1, 2, 3, 4, 5, where v h5 As the highest gear, the upward movement direction of the hook is determined as the positive direction, and the downward movement direction of the hook is determined as the negative direction. The detection process of the dynamic characteristics of the tower crane hook lifting motion is as follows: B3.1) Confirm that the hook is under rated load; B3.2) The hook stops at height h0; B3.3) Adjust the "acceleration and deceleration time" parameters of the hook lifting inverter; B3.4) Use the tower crane operation status detection module to obtain the hook height h in real time t ; B3.5) The hook is at height h0 and is suddenly lifted at the highest lifting speed v h5 Start the hook to move upward, and the hook speed increases from 0 to v h5 , the hook height reaches h1. During this process, if the boom swings greatly, return to step B3.2) and adjust the "acceleration and deceleration time" parameters of the lifting inverter; if the boom swings slightly, confirm that the inverter parameters are reasonable and execute step B3.6); B3.6) Calculate the maximum lifting speed v of the hook h5 Movement distance: h = |h1-h0|; the movement distance h is defined as the maximum speed v of the hook lifting movement h5 The corresponding hook lifting speed control threshold h5; According to the above method, the lifting speed v of the tower crane hook is detected respectively. h4 ,v h3 ,v h2 ,v h1 The corresponding hook lifting speed control thresholds are h4, h3, h2 and h1.

4. The three-dimensional path planning and tracking control system of a tower crane hook according to claim 1, characterized in that: The three-dimensional path planning module for the hook is operated by the tower crane driver through a handle to control the three-dimensional movement of the tower crane boom rotation, the trolley luffing and the hook lifting. The tower crane completes a complete lifting process of the hook from position A to position B along the path selected by the tower crane driver. In this process, the hook forms a three-dimensional path in space. The tower crane operation status detection module collects the tower crane operation status data in real time through three related sensors, and records the continuous position of the hook during the operation of the tower crane in real time. i (θ i ,r i ,h i ), so as to plan the three-dimensional path of the tower crane hook between position A and position B; at the same time, considering the particularity of the tower crane's rotation movement, in the manual planning process of the path, the direction of the tower crane's rotation movement is recorded, and the tower crane's rotation movement direction variable is set as F θ , then when the tower crane rotates counterclockwise, F θ =1, when the tower crane rotates clockwise F θ =0.

5. The three-dimensional path planning and tracking control system of a tower crane hook according to claim 1, characterized in that: The hook path tracking control module determines the forward point to be tracked and calculates the position error through the real-time detection of the hook's operating status and the planned path. It also uses the motion control method based on the dynamic characteristics of the tower crane to plan the three-dimensional motion direction and speed gear of the hook based on the dynamic performance of the hook's three-dimensional motion, and outputs the motion control signal to the tower crane's electrical control system to achieve three-dimensional path tracking motion of the tower crane hook under unmanned control.

6. The three-dimensional path planning and tracking control system of a tower crane hook according to claim 5, characterized in that: The hook path tracking control module includes two modes. One is the tracking control output of the hook from position A→position B, called path tracking control mode 1; the second is the tracking control output of the hook from position B→position A, called path tracking control mode 2. The paths of the two modes are the same but the movement directions are opposite. The two working modes are implemented separately in combination with the direction instructions of the relevant actions.

7. The three-dimensional path planning and tracking control system of a tower crane hook according to claim 5, characterized in that: The process of the hook path tracking control module is as follows: Step 1: Initialize each module; 1.1) Start the tower crane operation status detection module and the hook path tracking control module, and at the same time, start the communication between the hook path tracking control module and the tower crane electrical control system; 1.2) The hook path tracking control module reads the parameters set by the hook 3D path planning module, including: 3D path position point p n (θ n ,r n ,h n ) data, the total number of planned path tracking points is n; 1.3) The hook path tracking control module reads the dynamic performance parameters of the three-dimensional motion of the tower crane obtained by the tower crane dynamic performance detection module, including: the rotation speed control thresholds θ1, θ2, θ3, the amplitude change speed control thresholds r1, r2, r3, and the hook lifting speed control thresholds h1, h2, h3, h4, h5; 1.4) Set the hook path tracking spatial position error ε in the hook path tracking control module and update the foresight distance S of the tracking point dl ; Step 2: Determine the path tracking control mode; The hook path tracking control module obtains the current position D(θ t , r t ,h t ), calculate the spatial distance |Dp1| between the current position and the point p1 of the three-dimensional path planning, as well as the spatial distance between the current position and p n The spatial distance of the points |Dp2|; If |Dp1|<|Dp2|, it is determined to belong to path tracking control mode 1, and the tracking target point is set to p n ; Otherwise, it is determined to belong to path tracking control mode 2, and the tracking target point is set to p1; Step 3: Get the current position of the hook; The hook 3D path planning module uses three sensors installed on the tower crane to obtain the 3D coordinate value D (θ t , r t ,h t ); Step 4: Calculate the position deviation of the hook's three-dimensional path tracking; Let P k (θ k , r k ,h k ) is the three-dimensional coordinate of the current tracking point. In the process of hook path tracking control, the position deviation between the current position of the tower crane hook and the current tracking point is set as: angle deviation Δθ, amplitude deviation Δr and height deviation Δh, expressed as follows: Δθ=θ k -θ t , Δr=r k -r t , Δh=h k -h t ; Step 5: 3D path tracking control planning of tower crane hook based on dynamics; Step 6: Hook tracking control output; The hook path tracking control module sends the tower crane movement speed and direction instructions planned in step 5 to the tower crane electrical control system, and the tower crane electrical control system then controls the relevant drive equipment of the tower crane's three-dimensional movement to accurately complete the three-dimensional movement states of the boom rotation, trolley luffing and hook lifting; Step 7: Update the points to be tracked; Step 8: Determine whether the path tracking is completed; Calculate the current position D(θ t , r t ,h t ) and the spatial distance DP of the path tracking target point, The current state is path tracking mode 1, and the spatial distance DP expression is: The current state is path tracking mode 2, and the spatial distance DP expression is: If |DP|<ε, where ε is the error value, it means that the hook has reached the target position, the path tracking is completed, and the hook path tracking control process is exited; Otherwise, return to step 3 to continue tracking.

8. The three-dimensional path planning and tracking control system for a tower crane hook according to claim 7, characterized in that: In step 5, the specific process is: The tower crane path tracking control planning is to determine the current angular velocity ω of the rotary motion θ , the trolley variable amplitude motion speed v r , hook lifting speed v h ; At the same time, add a positive or negative sign prefix in front of each speed value to clarify the positive and negative directions of three-dimensional motion. The specific instructions are as follows: 5.1) The slewing motion planning of the tower crane boom is set as follows: The angular velocity of the tower crane boom rotation motion is set to three gears, denoted as ω θi , i=1,2,3, where ω θ3 As the highest gear; during the path tracking process, the direction of the slewing motion of the tower crane arm is determined by the variable F recorded during the path planning process. θ It is confirmed that there are several situations for the angular velocity gear setting of rotary motion: If |Δθ|<θ1, set the current rotation angular velocity ω θ =0; If θ1 < |Δθ| < θ2, set the current rotational angular velocity ω θ = ω θ1 ; If θ2 < |Δθ| < θ3, set the current rotational angular velocity ω θ = ω θ2 ; If θ3<|Δθ|, set the current rotation angular velocity ω θ =ω θ3 ; Among them, θ1, θ2, and θ3 are the rotation speed control thresholds corresponding to the three rotation motion angular speed gears respectively; 5.2) The tower crane trolley luffing motion planning is set as follows: The tower crane trolley variable amplitude motion is set to three gears, which are denoted as v ri , i=1,2,3, where v r3 As the highest gear, if the amplitude deviation Δr>0, the tower crane trolley changes its amplitude outward and the movement speed is positive; otherwise, the trolley changes its amplitude inward and the movement speed is negative; If Δr≤r1, set the current trolley amplitude movement speed v r =0, the trolley’s luffing motion stops; If r1<Δr≤r2, set the current trolley amplitude movement speed v r =v r1 ; If r2<Δr≤r3, set the current trolley amplitude movement speed v r =v r2 ; If r3<Δr, set the current trolley amplitude variation speed v r =v r3 ; Among them, r1, r2, and r3 are the amplitude deviation thresholds corresponding to the speed gears of the tower crane trolley. 5.3) The lifting motion planning of the tower crane hook is set as follows: The speed of the hook lifting movement is set to five gears, which are denoted by v hi , i=1,2,3,4,5, where v h5 As the highest gear; if the height deviation Δh>0, the tower crane will lift the hook upwards, and the lifting speed of the hook is positive; otherwise, the tower crane will drop the hook downwards, and the lifting speed of the hook is negative; If h5<|Δh|, set the current hook lifting speed v h =v h5 ; If h4 < |Δh| < h5, set the current hook lifting speed v h = v h4 ; If h3 < |Δh| < h4, set the current hook hoisting speed v h = v h3 ; If h2 < |Δh| < h3, set the current hook hoisting speed v h = v h2 ; If h1 < |Δh| < h2, set the current hook hoisting speed v h = v h1 ; If |Δh| h =0;​ Among them, h1, h2, h3, h4, and h5 are the height deviation thresholds corresponding to the lifting speed gears of the tower crane respectively.

9. The three-dimensional path planning and tracking control system for a tower crane hook according to claim 7, characterized in that: In step 7, the specific process is: The tower crane updates the tracking point by using a larger foresight distance S dl To determine; suppose the total number of path points recorded during the path planning process is n, and the current position coordinates of the hook are D(θ t , r t ,h t ), the current tracking point is p k (θ k ,r k ,h k ), then the update method of the point to be tracked is as follows: 7.1) In path tracking control mode 1, if the current tracking point p k (θ k ,r k ,h k ) is the path tracking target point p n (θ n ,r n ,h n ), then the point to be tracked is still p n (θ n ,r n ,h n ); otherwise, calculate the point p separately k+1 (θ k+1 ,r k+1 ,h k+1 ),…,p n (θ n ,r n ,h n ) and the current position of the hook D(θ t , r t ,h t ) i (i=k+1,…n), the distance calculation formula is as follows: The distance S i Distance between center and front sight s dl The distance point with the smallest error is identified as the point to be tracked; 7.2) In path tracking control mode 2, if the current tracking point p k (θ k ,r k ,h k ) is the path tracking target point p1(θ1,r1,h1), then the point to be tracked is still p1(θ1,r1,h1); otherwise, calculate the point p k-1 (θ k-1 ,r k-1 ,h k-1 ),…,p1(θ1,r1,h n ) and the current position of the hook D(θ t , r t ,h t ) i (i=1,…k-1), the distance calculation formula is as follows:

10. A three-dimensional path planning and tracking control method for a tower crane hook, which relies on the three-dimensional path planning and tracking control system for a tower crane hook as described in any one of claims 1 to 9, and is characterized in that: The implementation process is as follows: The tower crane driver performs an actual lifting operation, and the tower crane operation status detection module uses three sensors to obtain the position information of the hook in real time; The tower crane dynamics performance detection module uses the hook position information to detect the dynamics performance of the tower crane's three-dimensional motion and obtain the speed control thresholds for rotation, luffing, and hook lifting. The hook three-dimensional path planning module uses the three-dimensional coordinate values ​​of the hook to record the three-dimensional coordinates of all points in the storage path and complete the path planning of the hook between two points; The hook path tracking control module uses the tower crane's dynamic performance parameters and the three-dimensional coordinates of all hooks on the path, and sends control instructions to the tower crane's electrical control system according to the hook path tracking process to complete the hook path tracking control.

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