A method for preventing collisions in the space of tower crane loads based on motion trends

Abstract

This invention discloses a collision avoidance method for tower cranes and suspended loads based on motion trends. The method includes: acquiring static information of the tower crane and obstacle information as initial known information; updating the bottom height of the suspended load during lifting based on the static information of the tower crane; applying different collision detection algorithms based on the static information of the tower crane, obstacle information, and the bottom height of the suspended load during lifting; determining the motion trend of the suspended load based on the current position, speed, acceleration, and direction of the boom and the suspended load, as well as a preset safety reserve time Δt; determining the operational position relationship between the tower crane and surrounding tower cranes or obstacles; determining the current working state of the tower crane within the braking time; and further determining whether the tower crane is in a dangerous state, thereby ensuring the safety of the entire tower crane system. This invention considers the braking reaction time of different tower cranes and different operators, as well as the impact of the suspended load on the braking distance under different motion trends, and proposes a more refined collision risk assessment method.

Description

Technical Field

[0001] This invention relates to the field of safety management technology for tower crane operations at construction sites, and more specifically to a method for preventing collisions in the space of tower crane hoisted objects based on motion trends. Background Technology

[0002] In recent years, my country's construction industry has flourished, with the scale of construction continuously expanding and the total output value of the national construction industry increasing year by year. However, the continuous development of the construction industry has also brought significant challenges to the safety management of construction sites. To improve construction efficiency, the construction process is highly dependent on construction machinery, especially heavy machinery such as tower cranes. Tower cranes are often operated manually and require coordinated work, making them prone to safety accidents such as collisions with obstacles or between tower cranes, resulting in huge losses. Therefore, researching tower crane collision prevention methods has become an issue that cannot be ignored in construction site safety management. Existing tower crane collision prevention methods have the following drawbacks:

[0003] (1) Existing anti-collision methods assume that the suspended object is stationary when calculating the position of the suspended object, and do not take into account the motion trend of the suspended object due to inertia during the hoisting process.

[0004] (2) Existing collision avoidance methods use the distance between the suspended object and the danger zone at the current moment as the basis for judgment when predicting whether the suspended object is in the danger zone, which is not in line with the actual situation.

[0005] (3) The braking reaction time Δt varies for different tower cranes and different drivers. The braking time and moving distance also vary for the hoisted object at different hoisting speeds. Existing technology does not take into account this safety factor, which may lead to overly conservative judgments.

[0006] Therefore, how to provide a method for preventing collisions in the space of tower crane loads that can at least solve one of the above-mentioned technical problems is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0007] In view of this, the present invention provides a method for preventing collisions in the space of tower crane hoisted objects based on motion trends, which improves the accuracy and rationality of collision risk assessment.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] A method for preventing collisions in the space of tower crane loads based on motion trends, comprising:

[0010] Obtain static information of the tower crane and information about obstacles as initial known information;

[0011] Update the bottom height of the load during the lifting process based on the static information of the tower crane;

[0012] Different collision detection algorithms are used based on tower crane static information, obstacle information, and the bottom height of the hoisted object during the hoisting process;

[0013] Based on the preset safety reserve time Δt, it is determined whether the tower crane is in a dangerous state, and warning deceleration or alarm braking is performed according to the inspection results.

[0014] Preferably, different collision detection algorithms based on tower crane static information, obstacle information, and the bottom height of the suspended load during lifting specifically include:

[0015] Obtain the height of fixed obstacles and the type of collision based on obstacle information, and obtain the bottom height of the crane boom based on the static information of the tower crane;

[0016] Different collision detection algorithms are used based on the type of collision, the bottom height of the suspended object during the lifting process, the height of fixed obstacles, and the bottom height of the crane boom.

[0017] Preferably, the collision scenarios include fixed obstacles, space-restricted areas, and tower cranes.

[0018] Preferably, when the obstacle is a fixed obstacle, if the height of the fixed obstacle is not less than the height of the bottom of the crane boom, a crane boom collision algorithm is used; if the height of the bottom of the hoisted object is not greater than the height of the fixed obstacle and the height of the fixed obstacle is less than the height of the bottom of the crane boom, a hook collision algorithm is used; if the height of the fixed obstacle is less than the height of the bottom of the hoisted object during the hoisting process, then it is safe.

[0019] When the area is a spatially restricted area, if the restricted area is a crane boom restricted area or a crane tower interference area, the crane boom collision algorithm is used; if the restricted area is a hook restricted area, the hook collision algorithm is used; if the restricted area is a crane boom warning area or a hook warning area, an alarm is triggered.

[0020] When it is a tower crane, the tower crane collision algorithm is executed.

[0021] Preferably, the static information of the tower crane includes the tower crane's planar coordinates, jib length, relative height of the base, and tower crane height.

[0022] Preferably, the crane boom collision algorithm is as follows:

[0023] Using the tower crane's plane coordinates P a Draw a circle P with the crane boom length R3 as the center and the crane boom length R3 as the radius. a R3, retrieve all elements related to circle P. a The figure where the R3 boundary intersects;

[0024] Traverse each edge of the figure; if there exists an edge that intersects with circle P... a The intersection of R3 is analyzed, and the intersection point is used as the control point. The point located on circle P is then... a The endpoints of the figure inside R3 are used as control points, that is, to find all the points within circle P. aInside R3 or in circle P a Control points on R3;

[0025] Sequentially determine the coordinates of the control points and the tower crane P. a (X a ,Y a The angle values ​​between the line segment connecting the two points and due north are arranged in ascending order, with clockwise as positive. The differences between adjacent angles are calculated sequentially. If the difference is greater than π, the smaller of the adjacent angle values ​​is set as the maximum value θmax, and the difference between the larger value and 2π is set as the minimum value θmin. If all the differences between adjacent angles are less than π, the minimum and maximum angle values ​​in the sequence are taken as the minimum value θmin. min With the maximum value θ max Define [θ] min ,θ max [This refers to the alarm range;]

[0026] Based on the preset boom warning buffer angle θ k Define [θ] min -θ k ±2nπ,θ max +θ k [±2nπ] is the warning interval, where n is any natural number;

[0027] Obtain the boom slewing angles θ0 and θ1 corresponding to the previous time t0 and the current time t1 of the tower crane, and calculate the boom angular velocity ω at the current time t1. q1 and the angular acceleration a of the crane boom q1 :

[0028]

[0029]

[0030] Where, ω q0 This represents the angular velocity of the crane boom at time t0;

[0031] Based on the preset safety reserve time Δt and angular velocity ω q1 With angular acceleration a q1 Calculate the boom rotation angle θ after Δt. t :

[0032]

[0033] Determine the slewing angle θ of the crane boom t Is it within a warning or alarm range?

[0034] Preferably, the hook collision algorithm is as follows:

[0035] Using the tower crane's plane coordinates P aDraw a circle P with the crane boom length R3 as the center and the crane boom length R3 as the radius. a R3, traverse all circumscribed polygons or circumscribed circles of all obstacles in the plane, and obtain all objects related to circle P. a The figure F intersects the boundary of R3. x ;

[0036] Graphic F x The geometry expressed in terms of feature points is as follows: for a circumscribed polygon, the coordinates of each endpoint are used as feature points; for a circumscribed circle, the coordinates of the center and the boundary are used as feature points.

[0037] Obtain the boom slewing angles θ0 and θ1 corresponding to the previous time t0 and the current time t1, and the tower crane trolley amplitude value R corresponding to the previous time t0 and the current time t1. f0 R f1 Solve for the coordinates P of the suspended object at the current time t1. d (X d ,Y d The data and calculation formula are as follows:

[0038] X d =X a +R f1 sinθ1

[0039] Y d =Y a +R f1 cosθ1;

[0040] Find the angular velocities of the tower crane boom at time t0 and the current time t1. Angular acceleration of the tower crane boom at time t1 The tower crane trolley speed v at time t0 and the current time t1 f0 and v f1 At the current time t1, the acceleration a of the tower crane trolley is... f1 Then, the amplitude value R of the tower crane A trolley at time n*△t is obtained. fnt :

[0041]

[0042]

[0043]

[0044]

[0045]

[0046] Solve for the coordinates P of the suspended object after determining the motion trend of n times the preset safety reserve time n*△t. dnt (X dnt ,Ydnt The calculation formula is as follows:

[0047] X dnt =X a +R fnt sinθ nt

[0048] Y dnt =Y a +R fnt cosθ nt

[0049]

[0050] Where, θ nt This represents the slewing angle of the boom of tower crane A at time n*△t.

[0051] Determine the coordinates P of the suspended object dnt (X dnt ,Y dnt Is it in graph F? x If true, either inside or on the boundary, then calculate the position P of the suspended object after the preset safety reserve time Δt. dt (X dt ,Y dt ), and determine the position P of the suspended object. dt (X dt ,Y dt Is it in graph F? x The specific calculation process is as follows: (Inside or at the boundary)

[0052] X dt =X a +R ft sinθ t

[0053] Y dt =Y a +R ft cosθ t

[0054] Where, θ t R represents the slewing angle of the tower crane A's boom at time Δt. ft This represents the amplitude value of tower crane A trolley at time Δt.

[0055]

[0056]

[0057] Among them, R f0 R f1 This represents the amplitude values ​​of the tower crane trolley at time t0 and the current time t1;

[0058] If the coordinates of the suspended object are P dnt (X dnt ,Y dnt Not in graph F x Inside or at the boundary, it is through P d Coordinates and P dnt Coordinate solution for the trajectory P of the suspended object d P dnt Determine the trajectory P of the suspended object. d P dnt With graph F x If the sides intersect, an alarm and braking mechanism will be activated; if they do not intersect, the system is safe.

[0059] Determine the position P of the suspended object dt (X dt ,Y dt Is it in graph F? x When inside or on the boundary, if the position P of the suspended object is... dt (X dt ,Y dt If the object is inside or on the boundary of the graphic Fx, an alarm will be triggered to brake; otherwise, a warning will be issued to slow down the object.

[0060] Preferably, the bottom height H of the crane boom q for:

[0061] H q =H1+H2

[0062] Where H1 is the relative height of the base and H2 is the height of the tower crane.

[0063] Preferably, the initial bottom height H of the suspended object d for:

[0064] H d =H1+H5-H w

[0065] Where H1 is the relative height of the base, H5 is the initial hook height, and H w This refers to the height of the suspended object itself.

[0066] Preferably, the height of the bottom of the suspended object is continuously updated during the lifting process, and the updated height of the suspended object is:

[0067] H′ d =H d -H w

[0068] Among them, H w H is the height of the suspended object itself. d H' represents the original height of the suspended object before the update. d This refers to the bottom height of the object being lifted during the lifting and transport process.

[0069] The present invention has the following advantages:

[0070] (1) Consider the influence of moving direction, moving speed and acceleration on the movement of the suspended object and the judgment of the dangerous area;

[0071] (2) Considering the braking reaction time of different tower cranes and different drivers and the influence of the load on the braking distance under different motion trends, a more refined collision risk assessment method is proposed.

[0072] (3) The crane boom’s restricted area is controlled by the rotation angle θ. The calculation method is simple and efficient. At the same time, the crane boom’s position after the preset safety reserve time △t is predicted based on the crane boom’s movement trend, which improves the accuracy and rationality of collision risk judgment.

[0073] (4) For the collision problem between tower cranes, all possible collision scenarios of tower crane interference were traversed and algorithms were written accordingly; the collision trend after Δt was considered to reduce safety risks. Attached Figure Description

[0074] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0075] Figure 1 The attached diagram is an overall flowchart of the anti-collision method for tower crane loads based on motion trends.

[0076] Figure 2 The attached diagram shows the flowchart of the crane boom collision algorithm implementation.

[0077] Figures 3(a) and 3(b) are plan views of two scenarios of crane boom collision.

[0078] Figure 4 The attached diagram shows the flowchart of the hook collision algorithm implementation.

[0079] Figure 5 The attached diagram is a plan view of the hook collision. Detailed Implementation

[0080] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0081] This invention discloses a method for preventing collisions in the space of tower crane loads based on motion trends, such as... Figure 1 As shown, it includes:

[0082] S1: Obtain and input static information of this tower crane and obstacle data information from the cloud platform as initial known information;

[0083] S2: Based on the hook camera, determine the category of the suspended object and update the bottom height of the suspended object during the lifting process;

[0084] S3: Depending on the collision classification, different collision detection algorithms are used. The algorithm determines the movement trend of the boom or the load based on a preset safety reserve time Δt, including boom collision algorithm, hook collision algorithm, and multi-tower collision algorithm;

[0085] S4: Determine whether a warning deceleration or an alarm braking is needed based on the algorithm's output.

[0086] The symbols and acquisition methods for data involved in this invention are shown in the table below:

[0087] Table 1 Data by Category

[0088]

[0089]

[0090] S1 specifically refers to: the static data of the tower crane is acquired through the operator's black box, including the tower crane's planar coordinates, jib length, relative height of the base, and tower crane height. Taking tower crane A as an example, its planar center coordinates are P. a =(X a ,Y a Let R1, R2, and R3 be the counterweight boom length, amplitude distance, and jib length, respectively. Draw circles with these as radii to obtain the horizontal range covered by tower crane A during operation. Using the reference plane as 0, the vertical static data, including the jib base height H, can be obtained. q =H1+H2, Height H of the counterweight base p =H1 + H2 - H4, where H is the height of the suspended object. w Height H of the suspended object d =H1+H5-H w Where H1 is the relative height of the base, H2 is the tower crane height, H4 is the counterweight sag height, and H5 is the initial hook height obtained by the sensor. Since the counterweight sag height H4 is typically no more than 2m, for the sake of model simplification, let H... q =H p That is, the height of the bottom of the crane boom is equal to the height of the bottom of the counterweight.

[0091] Based on the construction site drawings, the cloud platform inputs the aforementioned obstacle and tower crane information to obtain the names, graphic classifications, collision classifications, numbers, fixed obstacle heights, and feature point coordinates of each endpoint of the graphic description of all obstacles, restricted areas, and tower cranes on the entire construction site.

[0092] S2 specifically involves: determining the category and volume adjustment parameters of the suspended object using a hook camera. This means acquiring images of the suspended object from a camera installed at the farthest end of the crane boom or on the luffing trolley, determining the object type using AI target recognition, and estimating the object's external dimensions (height H) using weight information obtained from sensors. w Modify the calculated value H′ of the bottom height of the load being lifted by this tower crane at this moment. d =H d -H w .

[0093] S3 specifically refers to the following: Due to the complex conditions at the construction site, the shapes of obstacles in the tower crane's working environment are diverse. In this method, the possible collision situations of this tower crane (Tower Crane A) are classified into three types: (1) spatially restricted areas (artificially set areas where the boom or hook is prohibited from entering, etc.); (2) fixed obstacles (such as existing buildings); (3) other adjacent tower cranes. For obstacles, the plane can be divided into "polygonal areas", "circular areas" and "tower crane areas" according to different geometric expressions. In the model, it can be simplified to a convex polygon. Considering the safety reserve, the approximate minimum circumscribed polygon or circumscribed circle is taken.

[0094] Obstacle characteristics are mainly distinguished by collision classification and obstacle fixed-point height. This is based on two parameters: height h and collision classification from the acquired fixed obstacle information, as well as the crane boom bottom height H from the acquired static data. q The height H of the suspended object in dynamic data d The parameters determine which algorithm to use. First, collision classification clarifies whether further attention should be paid to the height indicator. Then, based on the vertical relationship, it determines whether further inspection is needed and selects the appropriate algorithm. The specific algorithm selection criteria are shown in the table below.

[0095] Table 2 Specific Algorithm Judgment

[0096]

[0097]

[0098] like Figure 2 As shown, the calculation process of the crane boom collision algorithm includes:

[0099] 1) Using the tower crane's plane coordinates P a Find all circles centered on circle P. aThe diagrams for the collision with circle P are shown in Figures 3(a) and 3(b), with the crane boom length R3 as the radius. Traversing each edge of the diagram, if a collision with circle P exists... a The intersection points of R3 are identified and added to the control point set as control points; simultaneously, points located on circle P are also identified. a The graphical endpoints inside R3 are added as control points to the control point set;

[0100] 2) Sequentially determine the angle between the line segment connecting the control point and the tower crane coordinates Pa(Xa,Ya) and the due north direction. Taking clockwise as positive, arrange the angle values ​​in ascending order. Solve the difference between adjacent angles in sequence. If the difference is greater than π, set the smaller of the adjacent angle values ​​as the maximum value θ. max The difference between the larger value and 2π is taken as the minimum value θ. min If, after subtracting all angle values ​​in the sequence in order, the difference between adjacent angles is less than π, then the minimum and maximum angle values ​​in the sequence are taken as the minimum value θ. min With the maximum value θ max Define [θ] min ,θ max [This refers to the alarm range;]

[0101] 3) Based on the preset crane boom warning buffer angle θ k Define [θ] min -θ k ±2nπ,θ max +θ k [±2nπ] is the warning interval, where n is any natural number;

[0102] 4) Obtain the boom rotation angles θ0 and θ1 at the previous time t0 and the current time t1 using sensors, and calculate the angular velocity ω of the boom at the current time t1. q1 Angular acceleration a q1 information;

[0103]

[0104]

[0105] 5) According to the preset safety reserve time Δt (Δt is the safety reserve time required for the driver to complete the collision avoidance operation from receiving the pre-warning warning) and angular velocity ω q1 With angular acceleration a q1 Calculate the boom rotation angle θ after Δt. t For ease of calculation, the boom width is included in the safety reserve time Δt.

[0106]

[0107] By determining the boom rotation angle θ t Is it within the warning range? [θ] min -θ k ±2nπ,θ max +θ k ±2nπ] and alarm interval [θ] min ,θ max This information is used to determine whether to implement warning deceleration or alarm braking.

[0108] like Figure 4 As shown, areas where the crane boom can enter but the hook cannot are areas where a hook collision algorithm needs to be used. The specific process of the hook collision algorithm includes:

[0109] 1) Using the tower crane's plane coordinates P a Draw a circle P with the crane boom length R3 as the center and the crane boom length R3 as the radius. a R3, traverse all circumscribed polygons or circumscribed circles of all obstacles in the plane, and find all objects that intersect with circle P. a R3 collision graphic F x The planar diagram is shown in Figure 5; the circumscribed polygon uses the coordinates of each endpoint as feature points, and the circumscribed circle uses the coordinates of its center and its boundary as feature points.

[0110] 2) Obtain the tower crane boom rotation angles θ0 and θ1 at the previous time t0 and the current time t1, and the tower crane trolley amplitude value R through sensors. f0 R f1 Solve for the coordinates P of the suspended object. d (X d ,Y d The data and calculation formula are as follows:

[0111] X d =X a +R f1 sinθ1

[0112] Y d =Y a +R f1 cosθ1

[0113] Find the angular velocities of the tower crane boom at time t0 and the current time t1. Angular acceleration of the tower crane boom at time t1 The tower crane trolley speed v at time t0 and the current time t1 f0 and v f1 At the current time t1, the acceleration a of the tower crane trolley is... f1 Find the coordinates P of the suspended load after determining its motion trend, which is n times the preset safety reserve time n*△t (n is an integer greater than 1, which the user can set as needed). dnt (X dnt ,Y dntThe calculation formula is as follows:

[0114] X dnt =X a +R fnt sinθ nt

[0115] Y dnt =Y a +R fnt cosθ nt

[0116] Where, θ nt R represents the slewing angle of the boom of tower crane A at time n*△t. fnt The amplitude value of tower crane A trolley at time n*△t is represented by the following formula:

[0117]

[0118]

[0119]

[0120]

[0121]

[0122]

[0123] Determine P dnt (X dnt ,Y dnt Is it in graph F? x If true, either inside or on the boundary, then calculate the position P of the suspended object after the preset safety reserve time Δt. dt (X dt ,Y dt Is it in graph F? x If the value is false, then solve for the trajectory P of the suspended object. d P dnt (by P) d With P dnt (Two endpoints represent) and graph F x If the sides intersect, an alarm and braking mechanism will be activated; if they do not intersect, the system is safe. This is used to determine P. dnt In graph F x When the condition is true inside (or on the boundary), solve for the position P of the suspended object after the preset safety reserve time Δt. dt (X dt ,Y dt Is it in graph F? x The calculation formula is as follows: if true, an alarm and braking will be triggered; if false, a warning and deceleration will be triggered.

[0124] X dt =X a +R ft sinθ t

[0125] Y dt =Y a +R ft cosθ t

[0126] Where, θ t R represents the slewing angle of the tower crane A's boom at time Δt. ft The amplitude value of tower crane A trolley at time Δt is represented by the following formula:

[0127]

[0128]

[0129]

[0130] Where θ0 and θ1 represent the slewing angles of the tower crane boom at time t0 and the current time t1, respectively. These represent the angular velocities of the tower crane boom at times t1 and t0, respectively. This represents the angular acceleration of the tower crane boom at the current time t1.

[0131]

[0132]

[0133]

[0134] Among them, R f0 R f1 v represents the amplitude values ​​of the tower crane trolley at time t0 and the current time t1. f0 and v f1 Let a represent the tower crane trolley speeds at time t0 and the current time t1, respectively. f1 These represent the acceleration of the tower crane trolley at the current time t1.

[0135] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to the method section.

[0136] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preventing collisions in the space of a tower crane hoisted object based on motion trends, characterized in that, include: Obtain static information of the tower crane and information about obstacles as initial known information; Update the bottom height of the load during the lifting process based on the static information of the tower crane; Different collision detection algorithms are used based on tower crane static information, obstacle information, and the bottom height of the hoisted object during the hoisting process; Based on the preset safety reserve time △t, calculate the possible movement position of the tower crane within the braking time, determine whether the tower crane is in a dangerous state, and perform early warning deceleration or alarm braking based on the inspection results; Different collision detection algorithms are specifically implemented based on tower crane static information, obstacle information, and the bottom height of the suspended load during the lifting process. Obtain the height of fixed obstacles and the type of collision based on obstacle information, and obtain the bottom height of the crane boom based on the static information of the tower crane; Different collision detection algorithms are used based on the type of collision, the bottom height of the suspended object during the hoisting process, the height of fixed obstacles, and the bottom height of the crane boom. Collision scenarios include fixed obstacles, confined spaces, and tower cranes; When there is a fixed obstacle, if the height of the fixed obstacle is not less than the height of the bottom of the crane boom, the crane boom collision algorithm is used. If the height of the bottom of the hoisted object is not greater than the height of the fixed obstacle and the height of the fixed obstacle is less than the height of the bottom of the crane boom, the hook collision algorithm is used. If the height of the fixed obstacle is less than the height of the bottom of the hoisted object during the hoisting process, then it is safe. When the area is a spatially restricted area, if the restricted area is a crane boom restricted area or a crane tower interference area, the crane boom collision algorithm is used; if the restricted area is a hook restricted area, the hook collision algorithm is used; if the restricted area is a crane boom warning area or a hook warning area, an alarm is triggered. When the object is a tower crane, the tower crane collision algorithm is executed. The static information of the tower crane includes the tower crane's planar coordinates, jib length, relative height of the base, and tower crane height; The crane boom collision algorithm is as follows: Using the tower crane's plane coordinates P a Draw a circle P with the crane boom length R3 as the center and the crane boom length R3 as the radius. a R3, retrieve all elements related to circle P. a The figure where the R3 boundary intersects; Traverse each edge of the figure; if there exists an edge that intersects with circle P... a The intersection of R3 is analyzed, and the intersection point is used as the control point. The point located on circle P is then... a The endpoints of the figure inside R3 are used as control points, that is, to find all the points within circle P. a Inside R3 or in circle P a Control points on R3; Sequentially determine the control point and tower crane coordinates P a (X a ,Y a The angle between the line segment connecting the two points and true north is calculated, with clockwise as positive. The angle values ​​are arranged in ascending order, and the differences between adjacent angles are calculated sequentially. If the difference is greater than π, the smaller of the adjacent angle values ​​is set as the maximum value θ. max The difference between the larger value and 2π is taken as the minimum value θ. min If the difference between adjacent angles after subtracting all angles is less than π, then the minimum and maximum angle values ​​in the sequence are taken as the minimum value θ. min With the maximum value θ max Define [θ] min ,θ max [This refers to the alarm range;] Based on the preset boom warning buffer angle θ k Define [θ] min -θ k ±2nπ,θ max +θ k [±2nπ] is the warning interval, where n is any natural number; Obtain the boom slewing angles θ0 and θ1 corresponding to the previous time t0 and the current time t1 of the tower crane, and calculate the boom angular velocity ω at the current time t1. q1 and the angular acceleration a of the crane boom q1 : Where, ω q0 This represents the angular velocity of the crane boom at time t0; Based on the preset safety reserve time Δt and angular velocity ω q1 With angular acceleration a q1 Calculate the boom rotation angle θ after Δt. t : Determine the slewing angle θ of the crane boom t Is it within a warning or alarm zone? The hook collision algorithm is as follows: Using the tower crane's plane coordinates P a Draw a circle P with the crane boom length R3 as the center and the crane boom length R3 as the radius. a R3, traverse all circumscribed polygons or circumscribed circles of all obstacles in the plane, and obtain all objects related to circle P. a The figure F intersects the boundary of R3. x ; Graphic F x The geometry expressed in terms of feature points is as follows: for a circumscribed polygon, the coordinates of each endpoint are used as feature points; for a circumscribed circle, the coordinates of the center and the boundary are used as feature points. Obtain the boom slewing angles θ0 and θ1 corresponding to the previous time t0 and the current time t1, and the tower crane trolley amplitude value R corresponding to the previous time t0 and the current time t1. f0 R f1 Solve for the coordinates P of the suspended object at the current time t1. d (X d Y d The data and calculation formula are as follows: Find the angular velocities of the tower crane boom at time t0 and the current time t1. Angular acceleration of the tower crane boom at time t1 The tower crane trolley speed v at time t0 and the current time t1 f0 and v f1 At the current time t1, the acceleration a of the tower crane trolley is... f1 Then, the amplitude value R of the tower crane A trolley at time n*△t is obtained. fnt : Solve for the coordinates P of the suspended object after determining the motion trend of n times the preset safety reserve time n*△t. dnt (X dnt ,Y dnt The calculation formula is as follows: X dnt =X a +R fnt sinθ nt Y dnt =Y a +R fnt cosθ nt Where, θ nt This represents the slewing angle of the boom of tower crane A at time n*△t. Determine the coordinates P of the suspended object dnt (X dnt ,Y dnt Is it in graph F? x If true, either inside or on the boundary, then calculate the position P of the suspended object after the preset safety reserve time Δt. dt (X dt ,Y dt ), and determine the position P of the suspended object. dt (X dt ,Y dt Is it in graph F? x The specific calculation process is as follows: (Inside or at the boundary) X dt =X a +R ft sinθ t Y dt =Y a +R ft cosθ t Where, θ t R represents the slewing angle of the tower crane A's boom at time Δt. ft This represents the amplitude value of tower crane A trolley at time Δt. Among them, R f0 R f1 This represents the amplitude values ​​of the tower crane trolley at time t0 and the current time t1; If the coordinates of the suspended object are P dnt (X dnt ,Y dnt Not in graph F x Inside or at the boundary, it is through P d Coordinates and P dnt Coordinate solution for the trajectory P of the suspended object d P dnt Determine the trajectory P of the suspended object. d P dnt With graph F x If the sides intersect, an alarm and braking mechanism will be activated; if they do not intersect, the system is safe. Determining the position P of the suspended object dt (X dt ,Y dt Is it in graph F? x When inside or on the boundary, if the position P of the suspended object is... dt (X dt ,Y dt If the object is inside or on the boundary of the graphic Fx, an alarm will be triggered to brake; otherwise, a warning will be issued to slow down the object.

2. The method for preventing collisions in the space of tower crane loads based on motion trends according to claim 1, characterized in that, Crane boom bottom height H q for: H q =H1+H2 Where H1 is the relative height of the base and H2 is the height of the tower crane.

3. The method for preventing collisions in the space of tower crane loads based on motion trends according to claim 2, characterized in that, Initial height of the suspended object H d for: H d w ​ Where H1 is the relative height of the base, H5 is the initial hook height, and H w This refers to the height of the suspended object itself.

4. The method for preventing collisions in the space of tower crane hoisted objects based on motion trends according to claim 3, characterized in that, The height of the suspended object is continuously updated during the lifting process, and the updated bottom height of the suspended object is: H' d =H d -H w Among them, H w H is the height of the suspended object itself. d H' represents the original height of the suspended object before the update. d This refers to the bottom height of the object being lifted during the lifting and transport process.

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