Real-time collision early warning method for arch dam concrete cable crane

Abstract

The invention belongs to the field of concrete dam construction, and relates to an arch dam concrete cable crane real-time collision early warning method, which comprises the following steps: 1) determining a cable crane and arch dam construction entity space positioning node; 2) obtaining time sequence position information of a construction entity space positioning node; 3) calculating the rope length and the rope length change rate of an instantaneous lifting rope of the cable crane and the instantaneous swing angles of the cable crane hanging cage in the x-axis direction and the y-axis direction, and calculating the speeds and the accelerated speeds of an arch dam spreading machine and a vibrating machine and the angular speed and the angular accelerated speed of a tower crane; 4) predicting the running tracks of the spreading machine, the vibrating machine and the tower crane, and predicting the running track of the cable crane hanging cage by predicting the swing angle of the cable crane hanging cage; the real-time collision early warning method for the arch dam concrete cable crane is high in real-time performance, high in accuracy and high in safety degree. The real-time collision early warning method for the arch dam concrete cable crane has the advantages that the real-time performance is high, the accuracy is high, and the safety degree is high.

Description

Technical Field

[0001] The invention belongs to the field of concrete dam construction, and relates to a real-time collision warning method for an arch dam concrete cable crane, and in particular to a real-time collision warning method for a cable crane that takes into account the swing of a hanging pot and the movement information of obstacles. Background Art

[0002] Cable cranes are easy to install, flexible, have a large lifting capacity, and have a wide coverage range. They can serve the entire construction cycle and are widely used in many hydropower projects at home and abroad, especially in arch dam construction. As a key transportation equipment for arch dam concrete construction, the operation safety of cable cranes has always been a concern of construction units. However, the working state and operation control method of cable cranes are complex, and most arch dams are located in mountainous canyon areas, with narrow construction sites, frequent construction activities, and many cross-space operations, which poses great challenges to the safe operation of cable cranes. There are often collision risks between multiple cable cranes and between cable cranes and other construction entities, which has always been an important issue that plagues construction safety.

[0003] Real-time collision detection and early warning based on the current and next moment motion parameters of the cable crane and the surrounding construction entities are the key to ensuring the safe operation of the cable crane. However, the existing collision early warning methods based on real-time positioning information have not yet considered the swing characteristics of the cable crane's hanging pot and the motion information of obstacles, which greatly reduces the early warning effect of these algorithms. Therefore, it is necessary to construct a real-time collision detection method and early warning model for the cable crane based on the perception of the real-time motion state of the construction entity and the consideration of the swing characteristics of the hanging pot, and identify the risk based on the predicted trajectory to determine its impact range, thereby providing a favorable means for construction safety. Summary of the invention

[0004] In order to solve the above technical problems existing in the background technology, the present invention provides a real-time, accurate and safe arch dam concrete cable machine real-time collision warning method.

[0005] In order to achieve the above object, the present invention adopts the following technical solution:

[0006] A real-time collision warning method for an arch dam concrete cable crane, characterized in that the real-time collision warning method for an arch dam concrete cable crane comprises the following steps:

[0007] 1) Determine the spatial positioning nodes of the cable crane and the arch dam construction entity; the arch dam construction entity includes a tower crane, a leveling machine and a vibrator; the cable crane includes a cable crane hoisting tank and a cable crane trolley;

[0008] 2) Obtaining the temporal position information of the construction entity;

[0009] 3) According to the time sequence position information of the spatial positioning node obtained in step 2), the instantaneous lifting rope length of the cable crane, the instantaneous swing angle of the cable crane bucket in the x-axis and y-axis directions, and the speed, acceleration, angular velocity and angular acceleration of the arch dam construction entity are calculated;

[0010] 4) Based on the result of step 3), the running trajectory of the cable crane bucket and the running trajectory of the arch dam construction entity are predicted;

[0011] 5) Calculating the collision warning index based on the bounding volume based on the prediction result obtained in step 4);

[0012] 6) calculating the closest intersection distance and the closest intersection time based on the calculation results of step 5);

[0013] 7) Perform real-time collision warning based on the calculation results of step 6).

[0014] Preferably, in step 3), the instantaneous hoisting rope length of the cable crane and the instantaneous swing angle of the cable crane hanging pot in the x-axis direction and in the y-axis direction are calculated as follows:

[0015] a.1) Obtain the coordinates of the cable crane and the coordinates of its projection on the YOX plane; the coordinates of the cable crane include the coordinates of the cable crane trolley and the coordinates of the cable crane hanging pot. The coordinates of the cable crane trolley are A(x A ,y A , z A ); the coordinates of the projection of the cable car on the YOX plane are A′(x A ,y A , z B ); the coordinates of the cable car bucket are B(x B ,y B , z B ); The coordinate of the projection of the cable crane tank on the coordinate axis is B x (x B , 0, z B ) and B y (0,y B , z B );

[0016] in:

[0017] Point A represents the car;

[0018] Point B represents the hanging tank;

[0019] Point A′ represents the projection point of point A onto the yox plane;

[0020] B x Point represents the projection point of point B onto the x-axis;

[0021] B yPoint represents the projection point of point B onto the y-axis;

[0022] x A Indicates the position of point A on the x-axis;

[0023] y A Indicates the position of point A on the y-axis;

[0024] z A Indicates the position of point A on the z-axis;

[0025] x B Indicates the position of point B on the x-axis;

[0026] y B Indicates the position of point B on the y-axis;

[0027] z B Indicates the position of point B on the z-axis;

[0028] a.2) Calculate the length l of the hoisting rope and the swing angle of the cable crane bucket in the x-axis direction and the y-axis direction according to the coordinate data obtained in step a.1). The calculation method of the hoisting rope length l is:

[0029]

[0030] The calculation method of the swing angle of the hanging pot in the x-axis direction is:

[0031]

[0032] The calculation method of the swing angle of the hanging pot in the y-axis direction is:

[0033]

[0034] in:

[0035] θ x express Swing angle in the x-axis direction;

[0036] θ y express The swing angle in the y-axis direction;

[0037] From point A to point B x The vector of a point;

[0038] represents the vector from point A to point A′;

[0039] Represents the vector from point A to point B;

[0040] Representation vector Model;

[0041] Representation vector Model;

[0042] Representation vector Model.

[0043] Preferably, the acceleration and speed of the arch dam construction entity in step 3) are calculated as follows:

[0044]

[0045] in:

[0046] is the acceleration of the arch dam construction entity along the x-axis at the i-th sampling moment;

[0047] x i is the displacement of the arch dam construction entity along the x-axis between the i-th sampling time and the i+1 sampling time;

[0048] is the movement speed of the arch dam construction entity along the x-axis at the i-th sampling moment;

[0049] is the movement speed of the arch dam construction entity along the x-axis at the i+1th sampling moment;

[0050] represents the acceleration of the arch dam construction entity along the y-axis at the i-th sampling moment;

[0051] y i is the displacement of the arch dam construction entity along the y-axis between the i-th sampling time and the i+1 sampling time;

[0052] is the movement speed of the arch dam construction entity along the y-axis at the i-th sampling moment;

[0053] is the movement speed of the arch dam construction entity along the y-axis at the i+1th sampling moment;

[0054] represents the acceleration of the arch dam construction entity along the z-axis at the i-th sampling moment;

[0055] z i is the displacement of the arch dam construction entity along the z-axis between the i-th sampling time and the i+1 sampling time;

[0056] is the movement speed of the arch dam construction entity along the z-axis at the i-th sampling moment;

[0057] is the movement speed of the arch dam construction entity along the z-axis at the i+1th sampling moment;

[0058] Δt is the sampling time interval.

[0059] Preferably, the angular velocity and angular velocity calculation method of the arch dam construction entity in step 3) are:

[0060]

[0061] in:

[0062] is the angular acceleration of the arch dam construction entity around the x-axis at the i-th sampling moment;

[0063] θ xi is the angle of rotation of the arch dam construction entity around the x-axis between the i-th sampling time and the i+1 sampling time; is the angular velocity of the arch dam construction entity rotating around the x-axis at the i-th sampling moment;

[0064] is the angular velocity of the arch dam construction entity rotating around the x-axis at the i+1th sampling moment;

[0065] is the angular acceleration of the arch dam construction entity around the y-axis at the i-th sampling moment;

[0066] θ yi is the angle of rotation of the arch dam construction entity around the y-axis between the i-th sampling time and the i+1 sampling time; is the angular velocity of the arch dam construction entity rotating around the y-axis at the i-th sampling moment;

[0067] is the angular velocity of the arch dam construction entity rotating around the y-axis at the i+1th sampling moment;

[0068] is the angular acceleration of the arch dam construction entity around the z-axis at the i-th sampling moment;

[0069] θ zi is the angle of rotation of the arch dam construction entity around the z axis between the i-th sampling time and the i+1 sampling time; is the angular velocity of the arch dam construction entity rotating around the z axis at the i-th sampling moment;

[0070] is the angular velocity of the arch dam construction entity rotating around the z axis at the i+1th sampling moment;

[0071] Δt is the sampling time interval.

[0072] Preferably, the specific implementation method of predicting the cable car trajectory in step 4) is: a.1) obtaining the instantaneous coordinates of the trolley and the hanging tank;

[0073]

[0074] in:

[0075] m is the mass of the hanging tank;

[0076] M is the mass of the trolley;

[0077] l is the length of the lifting rope;

[0078] θ x It is the angle between the hoisting rope and the x-axis when the hanging tank swings;

[0079] θ y It is the angle between the hoisting rope and the y-axis when the hanging tank swings;

[0080] F M is the traction force on the car;

[0081] F l is the tension on the hoisting rope;

[0082] x M The traction force F on the car is M Coordinate of the force direction, projection length on the x-axis;

[0083] y M The traction force F on the car is M Coordinate of the force direction, projection length on the y-axis;

[0084] z M The traction force F on the car is M Coordinate of the force direction, projection length on the z-axis;

[0085] x m The tensile force F on the hoisting rope is l Coordinate of the force direction, projection length on the x-axis;

[0086] y m The tensile force F on the hoisting rope is l Coordinate of the force direction, projection length on the y-axis;

[0087] z m The tensile force F on the hoisting rope is l Coordinate of the force direction, projection length on the z-axis;

[0088] a.2) Predict the cable car trajectory based on the Lagrange equation; the general form of the Lagrange equation is as follows:

[0089]

[0090]

[0091] Where: L is the Lagrangian operator, T is the system kinetic energy, V is the system potential energy, q is the variable, i is the variable number, f i is the generalized external force; establish the Lagrange equations of the cable car-hoisting rope-hoisting tank system:

[0092]

[0093] Based on the Lagrange equations of the cable car-hoisting rope-hoisting tank system, the cable car-hoisting rope-hoisting tank dynamics model is obtained as follows:

[0094]

[0095] in:

[0096] l is the length of the lifting rope;

[0097] is the rate of change of the length of the hoisting rope;

[0098] are the accelerations of the hanging tank along the x and z axes respectively;

[0099] θ x It is the angle between the hoisting rope and the x-axis when the hanging tank swings;

[0100] is the angular velocity;

[0101] is the angular acceleration;

[0102] g is the acceleration due to gravity.

[0103] Preferably, when the arch dam construction entity is a tower crane, the specific implementation method of predicting the trajectory of the tower crane in step 4) is:

[0104] The trajectory equation of the tower crane is:

[0105]

[0106] in:

[0107] L t is the tower arm length;

[0108] Xa represents the position of A on the x-axis;

[0109] Ya represents the position of A on the Y axis;

[0110] Za represents the position of A on the Z axis;

[0111] ω and α are the tower arm rotation angular velocity and angular acceleration calculated in step 3) respectively;

[0112] When the arch dam construction entity is a flattening machine, the specific implementation method of predicting the trajectory of the flattening machine in step 4) is:

[0113]

[0114] in:

[0115] β is the angle between the dividing line of the casting bin strip and the horizontal river direction;

[0116] δ is the angle between the direction of movement of the liquidator and the strip dividing line;

[0117] v 平 is the speed of the liquidator at the i-1th sampling moment;

[0118] Z is the coordinate on the z-axis of the plane where the liquidator is located;

[0119] a 平 Indicates the acceleration in the direction of movement of the liquidator;

[0120] x i represents the displacement of the liquidator along the x-axis at the i-th sampling moment;

[0121] y i is the displacement of the liquidator along the y-axis at the i-th sampling moment;

[0122] z i is the displacement of the liquidator along the z-axis at the i-th sampling moment;

[0123] x i-1 represents the displacement of the liquidator along the x-axis between the i-1th and ith sampling moments;

[0124] y i-1 is the displacement of the liquidator along the y-axis between the i-1th and ith sampling moments;

[0125] t i represents the i-th time point;

[0126] t i-1 represents the i-1th time point;

[0127] When the arch dam construction entity is a vibrator, the specific implementation method of predicting the trajectory of the vibrator in step 4) is:

[0128]

[0129] in:

[0130] β is the angle between the dividing line of the casting bin strip and the horizontal river direction;

[0131] a 振 Indicates the acceleration in the moving direction of the vibrator;

[0132] v 振 is the speed of the vibrator at the i-1th sampling moment;

[0133] Z is the coordinate on the z-axis of the plane where the vibrator is located;

[0134] x i-1 represents the displacement of the vibrator along the x-axis between the i-1th and ith sampling moments;

[0135] y i-1 is the displacement of the vibrator along the y-axis between the i-1th and ith sampling moments;

[0136] x i represents the displacement of the vibrator along the x-axis at the i-th sampling moment;

[0137] y i is the displacement of the vibrator along the y-axis at the i-th sampling moment;

[0138] z i is the displacement of the vibrator along the z-axis at the i-th sampling moment; t i represents the i-th time point;

[0139] t i-1 represents the i-1th time point;

[0140] Preferably, the specific implementation of step 5) is:

[0141] 5.1) The collision detection boundary is initially divided according to the structural characteristics of the cable crane and the arch dam construction entity; the cable crane, the flattening machine and the vibrator adopt the spherical bounding box method; the tower crane adopts the axis-aligned bounding box method;

[0142] 5.2) The collision detection boundary of the cable car at different positions and motion states is subdivided to obtain the detection boundary; preferably, the specific implementation method of step 5.2) is: let the starting coordinate of the hanging tank at the nth collision detection be (x n ,y n , z n ), the lowest elevation of the entire dam casting surface is z′, and the predicted horizontal displacement is S n The maximum swing amplitudes along the river and across the river are r n1 、r n2 , determine the collision detection boundary as x∈[x n -krn1 , x n +S n +kr n1 ],y∈[y n -kr n2 ,y n +kr n2 ],z∈[z′,z n ], k ≥ 1;

[0143] 5.3) After the detection boundary is determined according to step 5.2), the obstacles within the detection boundary are identified according to the predicted trajectory coordinates of the obstacles, that is, the collision warning index is calculated.

[0144] Preferably, the specific implementation of step 6) is:

[0145] The time series prediction trajectory sequence of the cable crane and the arch dam construction entity in the construction scene is obtained, and the closest intersection distance and the closest intersection time are calculated according to the time series prediction trajectory sequence; the time series prediction trajectory sequence of the cable crane and the arch dam construction entity is a trajectory point set:

[0146] P i ={(t, x, y, z)|(t i0 , x i0 ,y i0 , z i0 ), (t i1 , x i1 ,y i1 , z i1 ),…,(t im , x im ,y im , z im )}

[0147] in:

[0148] i represents the number of the cable crane and arch dam construction entity;

[0149] m represents the time from the current time to t m The number of trajectory point groups consisting of time and coordinate points at a moment;

[0150] According to the Euclidean distance calculation formula, the intersection distance at time t is:

[0151]

[0152] in:

[0153] D t ij Table 1: Euclidean distance of the i-th arch dam construction entity at time t;

[0154] The intersection distance and intersection time set is expressed as:

[0155]

[0156] Preferably, the specific implementation of step 7) is:

[0157] 7.1) Set a minimum safety distance d between the cable crane and the arch dam construction entity;

[0158] 7.2) In chronological order, when the closest intersection distance calculated in step 6) When it is less than or equal to d for the first time, the nearest intersection distance and the nearest intersection time are output;

[0159] 7.3) Calculate the cable car braking time t according to the current state of the cable car z : The current state is the speed state when the current cable car running speed is equal to v;

[0160]

[0161] in:

[0162] v represents the running speed of the cable car;

[0163] a m Indicates the maximum acceleration when the cable mechanism is braked;

[0164] 7.4) The cable brake time t calculated according to step 7.3) z and the response delay time t of the cable crane decision and execution system x Calculate the minimum warning time of the cable car:

[0165] t j =t z +t x

[0166] Where: t j It is expressed as the minimum alert time;

[0167] 7.5) When the nearest intersection time t m Less than or equal to the minimum warning time t j When the nearest intersection time t m Greater than the minimum warning time t j When the cable car trolley-hoisting rope-hoisting tank dynamics model is called again to predict the swing angle of the hoisting rope, and then the predicted trajectory of the cable car hoisting tank under the maximum braking state is obtained, and then the nearest intersection distance is calculated. When the nearest intersection distance is greater than the minimum safety distance, it indicates that it is currently safe, but there is sufficient reaction time; when the nearest intersection distance is less than the minimum safety distance, it indicates that there is a risk of collision and time is tight.

[0168] Preferably, the arch dam concrete cable crane real-time collision warning method further comprises after step 7):

[0169] 8) The cable crane collision warning level is divided into four levels, and the danger level increases gradually from level one to level four, as follows:

[0170]

[0171] The advantages of the present invention are:

[0172] The present invention provides a real-time collision warning method for an arch dam concrete cable crane, comprising: 1) determining a spatial positioning node of a cable crane and an arch dam construction entity; the arch dam construction entity comprises a tower crane, a leveling machine and a vibrator; the cable crane comprises a cable crane hoisting pot and a cable crane trolley; 2) obtaining the time sequence position information of the construction entity; 3) calculating the instantaneous lifting rope length of the cable crane, the instantaneous swing angle of the cable crane hoisting pot in the x-axis and y-axis directions, and calculating the speed, acceleration, angular velocity and angular acceleration of the arch dam construction entity according to the time sequence position information of the spatial positioning node obtained in step 2); 4) predicting the running trajectory of the cable crane hoisting pot and the running trajectory of the arch dam construction entity based on the result of step 3); 5) calculating a collision warning index based on an enclosing body based on the prediction result obtained in step 4); 6) calculating the closest intersection distance and the closest intersection time based on the calculation result of step 5); 7) performing a real-time collision warning according to the calculation result of step 6). Compared with the prior art, the present invention has the following advantages: 1) Strong real-time performance: By real-time collection and prediction of the motion trajectory of the cable crane bucket and the warehouse surface construction machinery, potential collision risks can be discovered in time. 2) High accuracy: The use of advanced trajectory prediction algorithms to predict future trajectories improves the accuracy of collision risk assessment. 3) High degree of automation: The system can automatically perform data collection, trajectory prediction, collision risk assessment and early warning prompts, reducing the labor intensity and accuracy of manual monitoring. 4) High safety: Through timely early warning and automatic adjustment of the motion trajectory, the occurrence of collision accidents can be effectively avoided and the safety of arch dam construction can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0173] Figure 1 It is a schematic diagram of the cable crane positioning node;

[0174] Figure 2 It is a schematic diagram of tower crane positioning nodes;

[0175] Figure 3 It is a schematic diagram of the movement of the construction entity along the x-axis;

[0176] Figure 4 It is a schematic diagram of the object's rotation;

[0177] Figure 5 It is a simplified model of the cable car-hoisting rope-hoisting tank system;

[0178] Figure 6 It is a schematic diagram of the tower arm rotating around the tower body;

[0179] Figure 7 It is a schematic diagram of the direction of movement of the liquidator;

[0180] Figure 8 It is a schematic diagram of the movement direction of the vibrator;

[0181] Fig. 9 It is a schematic diagram of adaptive division of collision detection boundary;

[0182] Fig.10 It is a flow chart for calculating the closest intersection distance and the closest intersection time;

[0183] Fig.11 It is the real-time warning calculation process of cable crane collision;

[0184] Fig.12 It is a flow chart of the real-time collision warning method for arch dam concrete cable crane provided by the present invention. DETAILED DESCRIPTION

[0185] The technical solution provided by the present invention is described in detail below in conjunction with the accompanying drawings:

[0186] See also Fig.12 The present invention provides a real-time collision warning method for an arch dam concrete cable crane, which is to determine the positioning nodes of the cable crane and other construction entities, predict the running trajectory of the arch dam construction entity and the cable crane bucket under the condition of considering the swing of the bucket, calculate the closest intersection distance and the closest intersection time between the entity and the bucket, and perform a real-time collision warning for the cable crane. The method comprises the following steps:

[0187] Step 1: Initialize parameters. Set the initial velocity and angular velocity of the mechanical entity to 0, and set the initial state of the entity to 0.

[0188] Step 2: Data collection. The positions of the cable car and the hanging tank are obtained in real time through RFID and sensor positioning devices, and the time is recorded synchronously. At the same time, the positioning data of other construction entities are obtained, and the perception information of different entities is cleaned and integrated. Since the acquisition frequency of dynamic and static entity positioning data is different, in order to achieve the consistency of perception information at any time, it is first necessary to use the data sampling time of the dynamic entity as the criterion and fill the empty values ​​of the static entity according to the initial state.

[0189] Step 3: Based on the time-series position information, calculate the instantaneous length of the lifting rope, the instantaneous swing angle of the hoisting tank in the x-axis and y-axis directions, the speed, acceleration, angular velocity, and angular acceleration of the arch dam construction entity, where the construction entities involve the cable crane hoisting tank, cable crane trolley, leveling machine, vibrator, and tower crane.

[0190] The instantaneous length of the lifting rope and the calculation of the instantaneous swing angle of the hanging tank in the x-axis and y-axis directions are as follows: Figure 1 As shown, the coordinates of the trolley, the hanging tank and their projections on the coordinate axis, A(x A ,y A , z A )、A′(x A ,y A , z B )、B(x B ,y B , z B ), B x (x B , 0, z B ), B y (0,y B , z B );

[0191] in:

[0192] Point A represents the car;

[0193] Point B represents the hanging tank;

[0194] Point A′ represents the projection point of point A onto the yox plane;

[0195] B x Point represents the projection point of point B onto the x-axis;

[0196] B y Point represents the projection point of point B onto the y-axis;

[0197] x A Indicates the position of point A on the x-axis;

[0198] y A Indicates the position of point A on the y-axis;

[0199] z A Indicates the position of point A on the z-axis;

[0200] x B Indicates the position of point B on the x-axis;

[0201] y B Indicates the position of point B on the y-axis;

[0202] z B Indicates the position of point B on the z-axis.

[0203] The length of the lifting rope,

[0204] in:

[0205] L represents the length of the lifting rope.

[0206] The swing angle of the hanging tank in the x and y axis directions:

[0207] in:

[0208] θ x express The swing angle to the x-axis;

[0209] θ y express The swing angle along the y axis;

[0210] From point A to point B x The vector of a point;

[0211] represents the vector from point A to point A′;

[0212] Represents the vector from point A to point B;

[0213] Representation vector Model;

[0214] Representation vector Model;

[0215] Representation vector Model.

[0216] Determine the spatial positioning node of the tower crane. The main components of the tower crane are the tower body, tower arm, trolley, hoisting rope and hoisting weight. During the operation, the tower arm rotates around the slewing mechanism (the intersection of the tower body and the tower arm) and the positions of the trolley, hoisting rope and hoisting weight change. As an obstacle avoidance object during the operation of the cable crane, the hoisting tank cannot pass under the tower arm due to the limitation of the hoisting rope of the cable crane. Therefore, the present invention does not consider the motion trajectory of the tower crane hoisting weight and simplifies the tower crane as follows: Figure 2 The node model shown. After determining the spatial position of the positioning node, we can get:

[0217] a) Coordinates of nodes A, B and their projections on the coordinate axes: A(x A ,y A , z A )、B(x B ,y B , z B ), B x (x B , 0, z B );

[0218] in:

[0219] Point A represents the vertical intersection of the tower body and the tower arm;

[0220] Point B indicates the farthest point of the tower arm from the tower body;

[0221] x A Indicates the position of A on the x-axis;

[0222] y A Indicates the position of A on the y-axis;

[0223] z A Indicates the position of A on the z-axis;

[0224] x B Indicates the position of B on the x-axis;

[0225] y B Indicates the position of B on the y-axis;

[0226] z B Indicates the position of B on the z-axis.

[0227] b) Angle between tower arm and x-axis:

[0228] in:

[0229] θ represents the angle of rotation of the tower arm about the x-axis;

[0230] Represents the vector from point A to point B;

[0231] From point A to point B x The vector of a point;

[0232] Representation vector Model;

[0233] Representation vector Model.

[0234] c) Tower arm length:

[0235] Where: l represents the tower arm length.

[0236] Calculation of the speed and acceleration of the arch dam construction entity: Taking the rotation around the x-axis as an example, Figure 3 As shown in the figure, the sampling time interval of the three sets of positioning data is Δt. Due to the high frequency of data collection, the time interval between two adjacent sets of data is short. Therefore, it can be approximately considered that the movement of the construction entity along a certain dimension in each time interval is uniformly accelerated. According to the uniformly accelerated rotation calculation formula, it can be obtained:

[0237]

[0238] In the formula, x i is the displacement of the entity along the x-axis between the i-th and i+1-th sampling moments; is the velocity of the entity along the x-axis at the i-th sampling moment. Further, the acceleration of the entity along the x-axis at the i-th sampling moment can be obtained as:

[0239]

[0240] The final motion state of the entity in the i-th sampling interval is the initial motion state of the i+1-th sampling interval. According to the initial velocity along the x-axis at the i+1-th time point and acceleration The speed corresponding to the next sampling moment can be calculated as:

[0241]

[0242] The corresponding calculation entity movement parameters along the y-axis and z-axis directions:

[0243]

[0244] The initial velocity of the entity in each segment of the motion trajectory is 0, that is, v0=0. According to the above formula, the velocity and acceleration of the entire trajectory at each sampling moment can be deduced.

[0245] in:

[0246] a yi represents the acceleration along the y-axis at the i+1th moment;

[0247] y i is the displacement of the entity along the y-axis between the i-th and i+1-th sampling moments;

[0248] is the moving speed of the entity along the y-axis at the i-th sampling moment;

[0249] is the moving speed of the entity along the y-axis at the i+1th sampling moment;

[0250] a zi represents the acceleration along the z-axis at the i+1th moment;

[0251] z i is the displacement of the entity along the z-axis between the i-th and i+1-th sampling moments;

[0252] is the moving speed of the entity along the z-axis at the i-th sampling moment;

[0253] It is the movement speed of the entity along the z-axis at the i+1th sampling moment.

[0254] Calculation of angular velocity and angular acceleration of arch dam construction entity: Taking the rotation around the x-axis as an example, Figure 4 As shown, the sampling time interval of the three sets of positioning data is Δt. According to the uniform acceleration rotation calculation formula, we can get:

[0255]

[0256] In the formula, θ xi is the angle of rotation of the entity around the x-axis between the i-th sampling moment and the i+1 sampling moment; is the angular velocity of the entity rotating around the x-axis at the i-th sampling moment. Further, the angular acceleration of the entity rotating around the x-axis at the i-th sampling moment can be obtained as:

[0257]

[0258] The final motion state of the entity in the i-th sampling interval is the initial motion state of the i+1-th sampling interval. According to the initial angular velocity around the x-axis at the i+1-th time point and angular acceleration The angular velocity corresponding to the next sampling moment can be calculated as:

[0259]

[0260] Rotation parameters around the y-axis and z-axis:

[0261]

[0262] The initial angular velocity of the entity in each segment of the motion trajectory is 0, that is, ω0=0. According to the above formula, the angular velocity and angular acceleration of the entire trajectory at each sampling moment are deduced one by one.

[0263] in:

[0264] a yi represents the angular acceleration of rotation around the y-axis at the i-th time point;

[0265] is the angle of rotation of the entity around the y-axis between the i-th sampling moment and the i+1 sampling moment;

[0266] is the angular velocity of the entity rotating around the y-axis at the i-th sampling moment;

[0267] is the angular velocity of the entity rotating around the y-axis at the i+1th sampling moment;

[0268] a zirepresents the angular acceleration of rotation around the z-axis at the i-th moment;

[0269] is the angle of rotation of the entity around the z-axis between the i-th sampling moment and the i+1 sampling moment;

[0270] is the angular velocity of the entity rotating around the z-axis at the i-th sampling moment;

[0271] It is the angular velocity of the entity rotating around the z-axis at the i+1th sampling moment.

[0272] Step 4a: Prediction of the trajectory of the cable crane bucket. In the construction of the arch dam concrete strip, the fixed line is used for material feeding. The large car is stationary and only the trolley is in motion. Based on this, the model is built, and the direction from the main tower to the auxiliary tower of the cable crane is set as the positive direction of the x-axis. A right-hand coordinate system is established. The mass of the bucket is m, the mass of the trolley is M, the length of the lifting rope is l, and the angle between the lifting rope and the x-axis when the bucket swings is θ x , the angle between it and the y-axis is θ y , the traction force of the car is F M The tension on the hoisting rope is F l ,like Figure 5 As shown. Calculate the instantaneous coordinates of the trolley and the hanging tank, which are:

[0273]

[0274]

[0275] in:

[0276] x M Indicates the traction force of the trolley F M Coordinate of the force direction, projection length on the x-axis;

[0277] y M Indicates the traction force of the trolley F M Coordinate of the force direction, projection length on the y-axis;

[0278] z M Indicates the traction force of the trolley F M Coordinate of the force direction, projection length on the z-axis;

[0279] x m Indicates the traction force of the trolley F l Coordinate of the force direction, projection length on the x-axis;

[0280] y m Indicates the traction force of the trolley F l Coordinate of the force direction, projection length on the y-axis;

[0281] z m Indicates the traction force of the trolley F l Coordinate of the force direction, projected length on the z-axis.

[0282] Then, the cable car trajectory is predicted based on the Lagrange equation. The general form of the Lagrange equation is as follows:

[0283]

[0284]

[0285] Where: L is the Lagrangian operator, T is the system kinetic energy, V is the system potential energy, q is the variable, i is the variable number, f i is a generalized external force. In the windless state, the Lagrange equations of the cable car-hoisting rope-hoisting tank system can be established:

[0286]

[0287] The dynamic model of cable car-hoisting rope-hoisting tank is:

[0288]

[0289] Where l is the length of the lifting rope, is the rate of change of the length of the hoisting rope, is the acceleration of the hanging tank in the x-axis and z-axis directions, θ x is the swing angle with the x-axis, is the angular velocity around the x-axis, is the angular acceleration of rotation around the x-axis, g is the acceleration due to gravity, and the Lagrange equation is used to predict the spatial position of the hanging tank in a few seconds.

[0290] Step 4b: Tower crane trajectory prediction. The tower crane rotates around the tower body to establish a coordinate system and a tower crane motion trajectory prediction model, such as Figure 6 As shown, the trajectory equation of the tower crane is:

[0291]

[0292] Where l is the length of the tower arm, θ0 is the angle between the tower arm and the x-axis at the initial moment, ω and α are the angular velocity and angular acceleration of the tower arm, respectively.

[0293] Step 4c: Prediction of the trajectory of the flattening machine. Assume that the angle between the strip dividing line of the casting bin and the horizontal river direction is β, and the angle between the moving direction of the flattening machine and the strip dividing line is δ. As shown in the figure, the prediction model of the movement trajectory of the flattening machine can be obtained as follows:

[0294]

[0295] in:

[0296] a represents the acceleration in the moving direction of the liquidator;

[0297] x i-1 express;

[0298] y i-1 is the displacement of the entity along the y-axis between the i-1th and ith sampling moments;

[0299] t i-1 represents the i-1th time point.

[0300] Step 4d: Prediction of vibrator trajectory. The maximum working radius of the vibrator commonly used in current projects is about 7m, and the moving distance each time does not exceed 1.5 times of the maximum working radius. Assume that the angle between the dividing line of the casting bin strip and the horizontal river direction is β, such as Figure 8 As shown, the motion trajectory prediction model of the vibrator can be obtained as follows:

[0301]

[0302] Where: a represents the acceleration in the moving direction of the vibrator.

[0303] Step 5: Fit the bounding box and divide the collision detection boundary adaptively. Use different bounding boxes for different entities. Use axis-aligned bounding boxes for entities with regular shapes, such as tower cranes and dam bodies; use spherical bounding boxes for entities with turning and rotating movements such as cable crane buckets, flattening machines, and vibrators. After determining the appropriate collision detection algorithm, it is necessary to subdivide the collision detection boundaries of the cable crane at different positions and motion states. Assume that the starting coordinates of the bucket at the nth collision detection are (x n ,y n , z n ), the lowest elevation of the entire dam casting surface is z′, and the predicted horizontal displacement is S n The maximum swing amplitudes along the river and across the river are r n1 、r n2 , we can determine that the collision detection boundary is x∈[x n -kr n1 , x n +S n +kr n1 ],y∈[y n -kr n2 ,y n +kr n2 ],z∈[z′,z n ], k ≥ 1. The collision detection boundary is divided as follows Fig. 9 After the detection boundary is determined, the obstacles within the detection boundary are identified according to the predicted trajectory coordinates of the obstacles, and the collision warning index can be calculated.

[0304] Step 6: Calculate the nearest intersection distance and the nearest intersection time. Based on the high-frequency, high-precision motion state perception information and the construction entity trajectory prediction model, the time-series prediction trajectory sequence of the entities in the construction scene is obtained, and then the nearest intersection distance and the nearest intersection time are calculated. For different construction entities, static entities such as slopes, dams and their ancillary facilities can be considered as obstacles with zero speed and acceleration, and dynamic entities such as cable cranes and casting machinery can be considered as obstacles with non-zero speed or acceleration. Trajectory point set:

[0305] P i ={(t, x, y, z)|(t i0 , x i0 ,y i0 , z i0 ), (t i1 , x i1 ,y i1 , z i1 ),…,(t im , x im ,y im , z im )}

[0306] Among them, i represents the number of the construction entity, and m represents the time from the current time to t m The number of trajectory point groups composed of time and coordinate points at a moment. According to the Euclidean distance calculation formula, the intersection distance at moment t is:

[0307]

[0308] Where: D t ij Table 1: The Euclidean distance of the i-th construction entity at time t.

[0309] Therefore, the set of intersection distance and intersection time can be expressed as:

[0310]

[0311] Step 7: Determine the alarm level and issue alarm and obstacle avoidance decision information. In engineering, the cable crane tank and other entities are generally set with a minimum safety distance d, which is determined in chronological order. When it is less than or equal to d for the first time, the nearest intersection distance and the nearest intersection time are output. The calculation process is as follows Fig.10 When the nearest intersection distance is less than or equal to the minimum safety distance, it is judged that there is a possibility of collision, and it is necessary to further examine the time dimension indicators to determine the urgency of the danger. According to the current state of the cable car, the braking time t is calculated. z :

[0312]

[0313] Where: v represents the cable car running speed, a m Indicates the maximum acceleration when the cable is braked.

[0314] Assume that the response delay time of the cable machine decision and execution system is t x , the minimum warning time is:

[0315] t j =t z +t x

[0316] Where: t j Indicates the minimum warning time.

[0317] Determine the nearest intersection time t m Less than or equal to the minimum warning time t j When the nearest intersection time t m Greater than the minimum warning time t j When the cable car is braked, the cable car's motion state will change. For example, the swing amplitude increases. This needs to be discussed separately. The trajectory prediction model is called again to calculate the predicted trajectory under the set maximum braking state, and then the closest intersection distance is calculated. When the closest intersection distance is greater than the minimum safety distance, it indicates that the current situation is safe, but there is sufficient reaction time; when the closest intersection distance is less than the minimum safety distance, it indicates that there is a risk of collision and time is tight. Fig.11 Furthermore, the cable crane collision warning level can be divided into four levels, and the danger level increases gradually from level one to level four, as follows:

[0318]

[0319] When the present invention is in specific operation, the initial position and initial rope length of the trolley, the initial swing angle, speed, angular acceleration of the hanging pot, and the speed, acceleration, changing speed of the rope length, and changing acceleration of the trolley in the future are known. Then, the swing angle of the hanging pot in the future can be solved through the cable car trolley-hoisting rope-hanging pot dynamic model. Finally, the position of the trolley in the future, the rope length information plus the solved hanging pot swing angle can be used to solve the coordinates of the hanging pot. Although the dynamic model does not include the speed of the trolley and the changing speed of the rope length, it will be used in solving the position of the trolley and the rope length in the future. After the trolley position and rope length are obtained, plus the swing angle, the coordinates of the hanging pot can be solved. In fact, the hanging pot motion trajectory prediction involved in this invention is a trajectory prediction that takes the swing of the hanging pot into consideration.

Claims

1. A real-time collision warning method for arch dam concrete cable crane, characterized in that: The arch dam concrete cable crane real-time collision warning method comprises the following steps: 1) Determine the spatial positioning nodes of the cable crane and the arch dam construction entity; the arch dam construction entity includes a tower crane, a leveling machine and a vibrator; the cable crane includes a cable crane hoisting tank and a cable crane trolley; 2) Obtaining the temporal position information of the construction entity; 3) According to the time sequence position information of the spatial positioning node obtained in step 2), the instantaneous lifting rope length of the cable crane, the instantaneous swing angle of the cable crane bucket in the x-axis and y-axis directions, and the speed, acceleration, angular velocity and angular acceleration of the arch dam construction entity are calculated; 4) Based on the result of step 3), the running trajectory of the cable crane bucket and the running trajectory of the arch dam construction entity are predicted; 5) Calculating the collision warning index based on the bounding volume based on the prediction result obtained in step 4); 6) calculating the closest intersection distance and the closest intersection time based on the calculation results of step 5); 7) Perform real-time collision warning based on the calculation results of step 6).

2. The arch dam concrete cableway real-time collision warning method according to claim 1 is characterized by: In step 3), the calculation method of the instantaneous hoisting rope length of the cable crane and the instantaneous swing angle of the cable crane hanging pot in the x-axis direction and in the y-axis direction is: a.1) Obtain the coordinates of the cable crane and the coordinates of its projection on the YOX plane; the coordinates of the cable crane include the coordinates of the cable crane trolley and the coordinates of the cable crane hanging pot. The coordinates of the cable crane trolley are A(x A ,y A , z A ); the coordinates of the projection of the cable car on the YOX plane are A′(x A ,y A , z B ); the coordinates of the cable car bucket are B(x B ,y B , z B ); The coordinate of the projection of the cable crane tank on the coordinate axis is B x (x B , 0, z B ) and B y (0,y B , z B ); in: Point A represents the car; Point B represents the hanging tank; Point A′ represents the projection point of point A onto the yox plane; B x Point represents the projection point of point B onto the x-axis; B y Point represents the projection point of point B onto the y-axis; x A Indicates the position of point A on the x-axis; y A Indicates the position of point A on the y-axis; z A Indicates the position of point A on the z-axis; x B Indicates the position of point B on the x-axis; y B Indicates the position of point B on the y-axis; z B Indicates the position of point B on the z-axis; a.2) Calculate the length l of the hoisting rope and the swing angle of the cable crane bucket in the x-axis direction and the y-axis direction according to the coordinate data obtained in step a.1). The calculation method of the hoisting rope length l is: The calculation method of the swing angle of the hanging pot in the x-axis direction is: The calculation method of the swing angle of the hanging pot in the y-axis direction is: in: θ x express Swing angle in the x-axis direction; θ y express The swing angle in the y-axis direction; From point A to point B x The vector of a point; represents the vector from point a to point A′; Represents the vector from point A to point B; Representation vector Model; Representation vector Model; Representation vector Model.

3. The arch dam concrete cableway real-time collision warning method according to claim 2 is characterized in that: The calculation method of the acceleration and speed of the arch dam construction entity in step 3) is: in: is the acceleration of the arch dam construction entity along the x-axis at the i-th sampling moment; x i is the displacement of the arch dam construction entity along the x-axis between the i-th sampling time and the i+1 sampling time; is the movement speed of the arch dam construction entity along the x-axis at the i-th sampling moment; is the movement speed of the arch dam construction entity along the x-axis at the i+1th sampling moment; represents the acceleration of the arch dam construction entity along the y-axis at the i-th sampling moment; y i is the displacement of the arch dam construction entity along the y-axis between the i-th sampling time and the i+1 sampling time; is the movement speed of the arch dam construction entity along the y-axis at the i-th sampling moment; is the movement speed of the arch dam construction entity along the y-axis at the i+1th sampling moment; represents the acceleration of the arch dam construction entity along the z-axis at the i-th sampling moment; z i is the displacement of the arch dam construction entity along the z-axis between the i-th sampling time and the i+1 sampling time; is the movement speed of the arch dam construction entity along the z-axis at the i-th sampling moment; is the movement speed of the arch dam construction entity along the z-axis at the i+1th sampling moment; Δt is the sampling time interval.

4. The arch dam concrete cableway real-time collision warning method according to claim 3 is characterized in that: The calculation method of the angular velocity and angular velocity of the arch dam construction entity in step 3) is: in: is the angular acceleration of the arch dam construction entity around the x-axis at the i-th sampling moment; θ xi is the angle of rotation of the arch dam construction entity around the x-axis between the i-th sampling time and the i+1 sampling time; is the angular velocity of the arch dam construction entity rotating around the x-axis at the i-th sampling moment; is the angular velocity of the arch dam construction entity rotating around the x-axis at the i+1th sampling moment; is the angular acceleration of the arch dam construction entity around the y-axis at the i-th sampling moment; θ yi is the angle of rotation of the arch dam construction entity around the y-axis between the i-th sampling time and the i+1 sampling time; is the angular velocity of the arch dam construction entity rotating around the y-axis at the i-th sampling moment; is the angular velocity of the arch dam construction entity rotating around the y-axis at the i+1th sampling moment; is the angular acceleration of the arch dam construction entity around the z-axis at the i-th sampling moment; θ zi is the angle of rotation of the arch dam construction entity around the z axis between the i-th sampling time and the i+1 sampling time; is the angular velocity of the arch dam construction entity rotating around the z axis at the i-th sampling moment; is the angular velocity of the arch dam construction entity rotating around the z axis at the i+1th sampling moment; Δt is the sampling time interval.

5. The arch dam concrete cableway real-time collision warning method according to claim 4 is characterized in that: The specific implementation method of the cable car trajectory prediction in step 4) is: a.1) Obtain the instantaneous coordinates of the trolley and the hanging tank; in: m is the mass of the hanging tank; M is the mass of the trolley; l is the length of the lifting rope; θ x It is the angle between the hoisting rope and the x-axis when the hanging tank swings; θ y It is the angle between the hoisting rope and the y-axis when the hanging tank swings; F M is the traction force on the car; F l is the tension on the hoisting rope; x M The traction force F on the car is M Coordinate of the force direction, projection length on the x-axis; y M The traction force F on the car is M Coordinate of the force direction, projection length on the y-axis; z M The traction force F on the car is M Coordinate of the force direction, projection length on the z-axis; x m The tensile force F on the hoisting rope is l Coordinate of the force direction, projection length on the x-axis; y m The tensile force F on the hoisting rope is l Coordinate of the force direction, projection length on the y-axis; z m The tensile force F on the hoisting rope is l Coordinate of the force direction, projection length on the z-axis; a.2) Predict the cable car trajectory based on the Lagrange equation; the general form of the Lagrange equation is as follows: Where: L is the Lagrangian operator, T is the system kinetic energy, V is the system potential energy, q is the variable, i is the variable number, f i is the generalized external force; establish the Lagrange equations of the cable car-hoisting rope-hoisting tank system: Based on the Lagrange equations of the cable car-hoisting rope-hoisting tank system, the cable car-hoisting rope-hoisting tank dynamics model is obtained as follows: in: l is the length of the lifting rope; is the rate of change of the length of the hoisting rope; are the accelerations of the hanging tank along the x and z axes respectively; θ x It is the angle between the hoisting rope and the x-axis when the hanging tank swings; is the angular velocity; is the angular acceleration; g is the acceleration due to gravity.

6. The arch dam concrete cableway real-time collision warning method according to claim 5 is characterized by: When the arch dam construction entity is a tower crane, the specific implementation method of predicting the trajectory of the tower crane in step 4) is: The trajectory equation of the tower crane is: in: L t is the tower arm length; Xa represents the position of A on the x-axis; Ya represents the position of A on the Y axis; Za represents the position of A on the Z axis; ω and α are the tower arm rotation angular velocity and angular acceleration calculated in step 3) respectively; When the arch dam construction entity is a flattening machine, the specific implementation method of predicting the trajectory of the flattening machine in step 4) is: in: β is the angle between the dividing line of the casting bin strip and the horizontal river direction; δ is the angle between the direction of movement of the liquidator and the strip dividing line; v 平 is the speed of the liquidator at the i-1th sampling moment; Z is the coordinate on the z-axis of the plane where the liquidator is located; a 平 Indicates the acceleration in the direction of movement of the liquidator; x i represents the displacement of the liquidator along the x-axis at the i-th sampling moment; y i is the displacement of the liquidator along the y-axis at the i-th sampling moment; z i is the displacement of the liquidator along the z-axis at the i-th sampling moment; x i-1 represents the displacement of the liquidator along the x-axis between the i-1th and ith sampling moments; y i-1 is the displacement of the liquidator along the y-axis between the i-1th and ith sampling moments; t i represents the i-th time point; t i-1 represents the i-1th time point; When the arch dam construction entity is a vibrator, the specific implementation method of predicting the trajectory of the vibrator in step 4) is: in: β is the angle between the dividing line of the casting bin strip and the horizontal river direction; a 振 Indicates the acceleration in the moving direction of the vibrator; v 振 is the speed of the vibrator at the i-1th sampling moment; Z is the coordinate on the z-axis of the plane where the vibrator is located; x i-1 represents the displacement of the vibrator along the x-axis between the i-1th and ith sampling moments; y i-1 is the displacement of the vibrator along the y-axis between the i-1th and ith sampling moments; x i represents the displacement of the vibrator along the x-axis at the i-th sampling moment; y i is the displacement of the vibrator along the y-axis at the i-th sampling moment; z i is the displacement of the vibrator along the z-axis at the i-th sampling moment; t i represents the i-th time point; t i-1 represents the i-1th time point.

7. The arch dam concrete cableway real-time collision warning method according to claim 6 is characterized by: The specific implementation method of step 5) is: 5.1) The collision detection boundary is initially divided according to the structural characteristics of the cable crane and the arch dam construction entity; the cable crane, the flattening machine and the vibrator adopt the spherical bounding box method; the tower crane adopts the axis-aligned bounding box method; 5.2) The collision detection boundary of the cable car at different positions and motion states is subdivided to obtain the detection boundary; preferably, the specific implementation method of step 5.2) is: let the starting coordinate of the hanging tank at the nth collision detection be (x n ,y n , z n ), the lowest elevation of the entire dam casting surface is z′, and the predicted horizontal displacement is S n The maximum swing amplitudes along the river and across the river are r n1 、r n2 , determine the collision detection boundary as x∈[x n -kr n1 , x n +S n +kr n1 ],y∈[y n -kr n2 ,y n +kr n2 ],z∈[z′,z n ], k ≥ 1; 5.3) After the detection boundary is determined according to step 5.2), the obstacles within the detection boundary are identified according to the predicted trajectory coordinates of the obstacles, that is, the collision warning index is calculated.

8. The arch dam concrete cableway real-time collision warning method according to claim 7 is characterized by: The specific implementation method of step 6) is: The time series prediction trajectory sequence of the cable crane and the arch dam construction entity in the construction scene is obtained, and the closest intersection distance and the closest intersection time are calculated according to the time series prediction trajectory sequence; the time series prediction trajectory sequence of the cable crane and the arch dam construction entity is a trajectory point set: P i ={(t,x,y,z)|(t i0 ,x i0 ,y i0 ,z i0 ),(t i1 ,x i1 ,y i1 ,z i1 ),…,(t im ,x im ,y im ,z im )} in: i represents the number of the cable crane and arch dam construction entity; m represents the time from the current time to t m The number of trajectory point groups consisting of time and coordinate points at a moment; According to the Euclidean distance calculation formula, the intersection distance at time t is: in: D t ij Table 1: Euclidean distance of the i-th arch dam construction entity at time t; The intersection distance and intersection time set is expressed as:

9. The arch dam concrete cableway real-time collision warning method according to claim 8, characterized in that: The specific implementation of step 7) is: 7.1) Set a minimum safety distance d between the cable crane and the arch dam construction entity; 7.2) In chronological order, when the closest intersection distance calculated in step 6) When it is less than or equal to d for the first time, the nearest intersection distance and the nearest intersection time are output; 7.3) Calculate the cable car braking time t according to the current state of the cable car z : The current state is the speed state when the current cable car running speed is equal to v; in: v represents the running speed of the cable car; a m Indicates the maximum acceleration when the cable mechanism is braked; 7.4) The cable brake time t calculated according to step 7.3) z and the response delay time t of the cable crane decision and execution system x Calculate the minimum warning time of the cable car: t j =t z +t x Where: t j It is expressed as the minimum alert time; 7.5) When the nearest intersection time t m Less than or equal to the minimum warning time t j When the nearest intersection time t m Greater than the minimum warning time t j The cable car trolley-hoisting rope-hoisting tank dynamic model is called again to predict the swing angle of the hoisting rope, and then the predicted trajectory of the cable car hoisting tank under the maximum braking state is obtained, and then the nearest intersection distance is calculated. When the nearest intersection distance is greater than the minimum safety distance, it indicates that it is currently safe, but there is sufficient reaction time; when the nearest intersection distance is less than the minimum safety distance, it indicates that there is a risk of collision and time is tight.

10. The arch dam concrete cableway real-time collision warning method according to claim 9, characterized in that: The arch dam concrete cable crane real-time collision warning method further comprises after step 7): 8) The cable crane collision warning level is divided into four levels, and the danger level increases gradually from level one to level four, as follows:

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