A tower crane operation safety active early warning method and early warning system based on an internet of things

Abstract

The application relates to the technical field of engineering protection, and discloses a tower crane operation safety active early warning method and early warning system based on the Internet of Things. The method comprises the following steps: acquiring personnel position information of construction personnel and tower crane state information of a tower crane; mapping the personnel position information into a warning coordinate system to obtain personnel position coordinates, and mapping the tower crane state information into the warning coordinate system to obtain tower arm vector endpoint coordinates; calculating a first warning distance based on the personnel position coordinates, comparing the first warning distance with a preset first threshold value, and performing a first warning when the first warning distance is less than or equal to the preset first threshold value; calculating a second warning distance based on the personnel position coordinates, comparing the second warning distance with a preset second threshold value, and performing a second warning when the second warning distance is less than or equal to the preset second threshold value. The application solves the problems that the existing operation safety early warning method has poor timeliness and lacks dynamic protection.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of engineering protection, and in particular to a tower crane operation safety active early warning method and early warning system based on Internet of Things. BACKGROUND

[0002] The tower crane, also known as tower crane, is a rotating crane with a movable arm mounted on the upper part of a high tower. It has a large working space and is mainly used for vertical and horizontal transportation of materials and installation of building components during the construction process. The tower crane is mainly composed of a metal structure, a working mechanism and an electrical system. The metal structure includes the tower body, the movable arm and the base, the working mechanism includes the lifting structure, the amplitude changing structure, the rotating structure and the walking structure, and the electrical system includes the motor, the controller, the power distribution cabinet, the connecting line, the signal device and the lighting device.

[0003] At present, there are several problems in the safety protection of tower crane during operation. First, the visual blind area problem, the tower crane driver cannot fully observe the activities of the personnel below the boom due to the operating height (usually > 30 meters) and the location limitation of the cab, and the ground personnel also have difficulty in real-time sensing the tower crane movement state due to the visual angle limitation. Second, the passive protection has defects, the existing solutions mainly rely on static measures such as safety warning signs and physical isolation barriers, which cannot dynamically respond to the situation of personnel accidentally entering the dangerous area. Moreover, the existing early warning methods have poor timeliness, the coverage range of traditional sound and light alarms is limited, and they cannot conduct directional early warning for specific personnel. It can be seen that the existing operation safety early warning method has the problems of poor timeliness and lack of dynamic protection. SUMMARY

[0004] The present application provides a tower crane operation safety active early warning method and early warning system based on Internet of Things to solve the problem of poor timeliness and lack of dynamic protection in the existing operation safety early warning method.

[0005] In order to achieve the above purpose, the present application realizes the technical scheme as follows:

[0006] In the first aspect, the present application provides a tower crane operation safety active early warning method based on Internet of Things, which comprises:

[0007] An early warning coordinate system with the tower crane rotating center as the origin is constructed, and the personnel position information of the construction personnel is obtained, and the personnel position information is mapped into the early warning coordinate system to obtain the personnel position coordinates;

[0008] The tower crane state information of the tower crane is obtained, and the tower arm vector endpoint coordinates are determined in the early warning coordinate system based on the tower crane state information;

[0009] calculating a first-level warning distance based on the personnel position coordinates, comparing the first-level warning distance with a preset first threshold, and performing a first-level warning when the first-level warning distance is less than or equal to the preset first threshold;

[0010] calculating a false-alarm-preventing distance based on the personnel position coordinates and the tower arm vector endpoint coordinates, and performing a second-level warning distance calculation when the false-alarm-preventing distance satisfies a second-level warning calculation condition;

[0011] The second-level warning distance calculation includes: calculating a second-level warning distance based on the personnel position coordinates, comparing the second-level warning distance with a preset second threshold, and performing a second-level warning when the second-level warning distance is less than or equal to the preset second threshold.

[0012] Optionally, the false-alarm-preventing distance calculation includes:

[0013] Before the second-level warning distance is calculated, a false-alarm-preventing distance is calculated based on the personnel position coordinates and the tower arm vector endpoint coordinates, and the false-alarm-preventing distance calculation satisfies the following relationship:

[0014] ;

[0015] In the formula, D is the false-alarm-preventing distance, is an x-axis coordinate value of the personnel position coordinates, is an x-axis coordinate value of the tower arm vector endpoint coordinates, is a y-axis coordinate value of the personnel position coordinates, is a y-axis coordinate value of the tower arm vector endpoint coordinates.

[0016] The second-level warning calculation condition includes:

[0017] comparing the false-alarm-preventing distance with a tower arm working radius in the tower state information;

[0018] When 0≤D≤R 2 , the second-level warning calculation condition is satisfied, and the second-level warning distance is calculated; when D>R 2 , the second-level warning calculation condition is not satisfied, and the second-level warning distance is not calculated, where R is the tower arm working radius.

[0019] Optionally, the mapping of the personnel position information into the early warning coordinate system to obtain the personnel position coordinates includes:

[0020] constructing a mapping function between a geographic coordinate system and the early warning coordinate system, and mapping the personnel position information obtained based on the geographic coordinate system into the early warning coordinate system by using the mapping function to obtain an x-axis coordinate value and a y-axis coordinate value based on the early warning coordinate system;

[0021] The x-axis coordinate value and the y-axis coordinate value of the personnel position coordinate are obtained based on the x-axis coordinate value and the y-axis coordinate value of the early warning coordinate system.

[0022] Optionally, the determination of the tower arm vector end point coordinate comprises:

[0023] The x-axis coordinate value and the y-axis coordinate value of the tower arm vector end point coordinate are calculated based on the tower arm rotation angle and the tower arm working radius in the tower state information, and the following relationship is satisfied:

[0024] ;

[0025] ;

[0026] In the formula, is the tower arm working radius, is the tower arm rotation angle, is the x-axis coordinate value of the tower arm vector end point coordinate, is the y-axis coordinate value of the tower arm vector end point coordinate.

[0027] The tower arm vector end point coordinate is obtained based on the x-axis coordinate value and the y-axis coordinate value of the tower arm vector end point coordinate.

[0028] Optionally, the calculation of the first warning distance comprises:

[0029] The first warning distance is calculated based on the x-axis coordinate value and the y-axis coordinate value of the personnel position coordinate, and the following relationship is satisfied:

[0030] ;

[0031] In the formula, is the first warning distance, is the x-axis coordinate value of the personnel position coordinate, is the y-axis coordinate value of the personnel position coordinate.

[0032] Optionally, the comparison of the first warning distance with the preset first threshold value and the first warning when the first warning distance is less than or equal to the preset first threshold value comprise:

[0033] A safety margin value is determined, the sum of the tower arm working radius and the safety margin value is taken as the preset first threshold value, and the first warning distance is compared with the preset first threshold value.

[0034] When , the first warning is performed, and when , the first warning is not performed, wherein d1 is the first warning distance, R is the tower arm working radius, is the safety margin value.

[0035] Optionally, the calculating the secondary warning distance comprises:

[0036] calculating the secondary warning distance based on the x-axis coordinate value, the y-axis coordinate value in the personnel position coordinate and the tower arm rotation angle, and the calculation satisfies the following relationship:

[0037] ;

[0038] ;

[0039] In the formula, is the secondary warning distance, is the x-axis coordinate value in the personnel position coordinate, is the y-axis coordinate value in the personnel position coordinate, is an intermediate variable in the calculation, is the rotation angle.

[0040] Optionally, the comparing the secondary warning distance with the preset second threshold value and performing the secondary warning when the secondary warning distance is less than or equal to the preset second threshold value comprises:

[0041] determining the preset second threshold value and comparing the secondary warning distance with the preset second threshold value;

[0042] when ≤ , performing the secondary warning and automatically suspending the tower crane operation, and when > , not performing the secondary warning.

[0043] In a second aspect, the embodiments of the present application provide a tower crane operation safety active early warning system based on the Internet of Things, comprising a wearable terminal, a state acquisition unit and a central processing platform.

[0044] The wearable terminal is used to acquire personnel position information of a construction personnel in real time, and send the personnel position information to the central processing platform.

[0045] The state acquisition unit is used to acquire tower crane state information of a tower crane in real time, and send the tower crane state information to the central processing platform.

[0046] The central processing platform is configured to construct an early warning coordinate system with the center of the tower crane slewing as the origin, map personnel position information into the early warning coordinate system to obtain personnel position coordinates, map tower crane state information into the early warning coordinate system to obtain tower arm vector endpoint coordinates, calculate a first warning distance based on the personnel position coordinates, compare the first warning distance with a preset first threshold, and perform a first warning when the first warning distance is less than or equal to the preset first threshold; calculate a second warning distance based on the personnel position coordinates, compare the second warning distance with a preset second threshold, and perform a second warning when the second warning distance is less than or equal to the preset second threshold.

[0047] The central processing platform is further configured to calculate a false alarm prevention distance according to the personnel position coordinates and the tower arm vector endpoint coordinates, and perform a second warning distance calculation when the false alarm prevention distance meets a second warning calculation condition.

[0048] Optionally, the wearable terminal comprises a positioning module, a compensation module and a voice broadcast unit.

[0049] The positioning module is configured to obtain personnel position information of a construction worker and send the personnel position information to the compensation module.

[0050] The compensation module is configured to compensate and correct the personnel position information and send the compensated and corrected personnel position information to the central processing platform.

[0051] The voice broadcast unit is configured to receive first warning information issued when the central processing platform performs a first warning and second warning information issued when the central processing platform performs a second warning, and perform a first warning reminder based on the first warning information and a second warning reminder based on the second warning information.

[0052] Beneficial effects:

[0053] The tower crane operation safety active early warning method based on the Internet of Things provided by the application can accurately determine whether a person is in a tower crane operation area or directly below a tower arm in real time by combining high-precision positioning technology with geometric calculation, effectively reduces the risk of safety accidents, improves the timeliness of the early warning method, and adopts a hierarchical early warning mechanism of a first level (entering an operation radius) and a second level (entering directly below the tower arm), which can distinguish different risk levels, focus on high-risk scenarios (directly below the tower arm), reduce unnecessary interference, and solve the problem of missing dynamic protection in the existing early warning method. At the same time, the geometric model excludes false triggering in non-dangerous areas, especially avoids false judgment when a person is located on the extension line of the tower arm, and improves the credibility of the system. BRIEF DESCRIPTION OF DRAWINGS

[0054] Figure 1A flow chart of the tower crane operation safety active early warning method based on the Internet of Things for the preferred embodiment of the present application;

[0055] Figure 2 A structure schematic diagram of the tower crane operation safety active early warning system based on the Internet of Things for the preferred embodiment of the present application. DETAILED DESCRIPTION

[0056] The technical solutions of the present application will be described in detail below. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work shall fall within the scope of the present application.

[0057] Unless otherwise defined, the technical terms or scientific terms used in the present application shall be understood as the usual meanings understood by those skilled in the art to which the present application belongs. The terms "first", "second" and similar terms used in the present application do not represent any order, quantity or importance, but are only used to distinguish different components. Similarly, the terms "one" or "a" and similar terms do not represent a quantity limitation, but represent the existence of at least one. The terms "connected" or "connected" and similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms "up", "down", "left", "right" and the like are only used to represent relative positional relationships, and when the absolute position of the described object changes, the relative positional relationship also changes accordingly.

[0058] Please refer to Figure 1 The present application provides a tower crane operation safety active early warning method based on the Internet of Things, which comprises the following steps:

[0059] An early warning coordinate system with the center of tower crane rotation as the origin is constructed, and the personnel position information of the construction personnel is obtained, and the personnel position information is mapped into the early warning coordinate system to obtain personnel position coordinates;

[0060] The tower crane state information of the tower crane is obtained, and the tower arm vector endpoint coordinates are determined in the early warning coordinate system based on the tower crane state information;

[0061] The first warning distance is calculated based on the personnel position coordinates, the first warning distance is compared with the preset first threshold value, and the first warning is performed when the first warning distance is less than or equal to the preset first threshold value;

[0062] The anti-misjudgment distance is calculated based on the personnel position coordinates and the tower arm vector endpoint coordinates, and the second warning distance calculation is performed when the anti-misjudgment distance meets the second warning calculation condition;

[0063] The secondary warning distance calculation comprises: calculating the secondary warning distance based on the personnel position coordinates, comparing the secondary warning distance with a preset second threshold, and performing secondary warning when the secondary warning distance is less than or equal to the preset second threshold.

[0064] In the above embodiment, by combining high-precision positioning technology with geometric calculation, it can be determined in real time and accurately whether the personnel are in the tower crane operation area or directly below the tower arm, effectively reducing the risk of safety accidents, improving the timeliness of the early warning method, and adopting a hierarchical early warning mechanism of a first level (entering the operation radius) and a second level (entering directly below the tower arm), which can distinguish different risk levels, focus on high-risk scenarios (directly below the boom), reduce unnecessary interference, and solve the problem of dynamic protection missing in the existing early warning method. At the same time, by using the geometric model to exclude false triggering in non-dangerous areas, especially to avoid false judgment when the personnel are on the extension line of the tower arm, the system reliability is improved.

[0065] The personnel position can be obtained in real time through the personnel position coordinates, so as to determine whether the construction personnel are currently in a dangerous area through the personnel position coordinates, and whether warning calculation is needed. The dangerous area is mainly delimited based on the tower arm of the tower crane, and the length of the tower arm is fixed. Therefore, when determining the dangerous area, no calculation is needed, only a direct determination based on the length of the tower arm and the position of the construction personnel is needed. At the same time, the warning calculation is divided into first-level warning calculation and second-level warning calculation. The first-level warning calculation is when the construction personnel are in the operation radius of the tower crane boom, and the second-level warning calculation is when the construction personnel are directly below the tower arm. This division further divides the dangerous area, so that the construction personnel in different divided dangerous areas can receive different degrees of warning, further clarifying the danger level of different dangerous areas.

[0066] Optionally, the anti-misjudgment distance is calculated based on the personnel position coordinates and the tower arm vector endpoint coordinates, comprising:

[0067] Before calculating the secondary warning distance, the anti-misjudgment distance is calculated based on the personnel position coordinates and the tower arm vector endpoint coordinates. The calculation of the anti-misjudgment distance satisfies the following relationship:

[0068] ;

[0069] In the formula, D is the anti-misjudgment distance, is the x-axis coordinate value of the personnel position coordinates, is the x-axis coordinate value of the tower arm vector endpoint coordinates, is the y-axis coordinate value of the personnel position coordinates, is the y-axis coordinate value of the tower arm vector endpoint coordinates;

[0070] When the anti-misjudgment distance meets the secondary warning distance calculation condition, the secondary warning distance calculation is performed, including:

[0071] The anti-misjudgment distance is compared with the tower arm working radius in the tower state information;

[0072] When 0≤D≤R 2 , the secondary warning distance calculation condition is met, and the secondary warning distance is calculated; when D>R 2 , the secondary warning distance calculation condition is not met, and the secondary warning distance calculation is not performed, wherein R is the tower arm working radius.

[0073] In the above embodiment, compared with the first warning, the warning level of the second warning is higher, which also means that the position of the construction personnel is more dangerous. Therefore, the calculation level of the second warning will be higher than that of the first warning. However, frequent calculation of the second warning condition will make the calculation of the first warning lag, resulting in that the construction personnel in the first warning area cannot be reminded in time. Therefore, it is extremely important to set an anti-misjudgment mechanism to limit the calculation of the second warning. Under the anti-misjudgment mechanism, by setting a fixed data update interval, the continuity of the construction personnel motion track can be ensured, and at the same time, the lag of the first warning calculation can be avoided. The timeliness and effectiveness of the first warning reminder are ensured. For the data update interval, it can be determined according to the activity frequency of the construction personnel. If the construction personnel frequently moves under the tower crane, the anti-misjudgment distance update interval can be set to 2 seconds. If the construction personnel does not frequently move under the tower crane, the anti-misjudgment distance update interval can be set to 5 seconds or even 10 seconds. Only when the anti-misjudgment mechanism is triggered and the anti-misjudgment distance reaches the distance that needs to be calculated for the second warning, the corresponding calculation of the second warning is started, which can also improve the accuracy of the warning. This dynamic protection mechanism is more suitable for complex construction site conditions.

[0074] Optionally, the personnel position information is mapped into the early warning coordinate system to obtain personnel position coordinates, including:

[0075] A mapping function between the geographic coordinate system and the early warning coordinate system is constructed, and the personnel position information obtained based on the geographic coordinate system is mapped into the early warning coordinate system by using the mapping function to obtain an x-axis coordinate value and a y-axis coordinate value based on the early warning coordinate system;

[0076] The x-axis coordinate value and the y-axis coordinate value based on the early warning coordinate system are taken as the x-axis coordinate value and the y-axis coordinate value of the personnel position coordinates.

[0077] In the above embodiment, for the construction of the mapping function, it is the process of converting the east longitude coordinate and the north latitude coordinate in the geographic coordinate system into the x-axis coordinate and the y-axis coordinate in the early warning coordinate system. First, the position of the coordinate origin in the early warning coordinate system in the geographic coordinate system is determined, and then the geographic coordinate system position of the coordinate origin in the early warning coordinate system can be used to convert the coordinates in the geographic coordinate system into the coordinates in the early warning coordinate system. In this way, the geographic coordinate system coordinates corresponding to the personnel position information can be successfully converted into the early warning coordinate system coordinates corresponding to the personnel position coordinates, so as to facilitate the calculation of the personnel position.

[0078] Optionally, the tower arm vector endpoint coordinate is determined in the early warning coordinate system based on the tower crane state information, including:

[0079] The x-axis coordinate value of the tower arm vector endpoint coordinate and the y-axis coordinate value of the tower arm vector endpoint coordinate are calculated based on the tower arm rotation angle and the tower arm working radius in the tower crane state information, and the following relationship is satisfied:

[0080] ;

[0081] ;

[0082] In the formula, the tower arm working radius, the tower arm rotation angle, the x-axis coordinate value of the tower arm vector endpoint coordinate, the y-axis coordinate value of the tower arm vector endpoint coordinate;

[0083] The tower arm vector endpoint coordinate is obtained based on the x-axis coordinate value of the tower arm vector endpoint coordinate and the y-axis coordinate value of the tower arm vector endpoint coordinate.

[0084] In the above embodiment, since the tower arm rotates around the origin of the early warning coordinate system, only the rotation radius, i.e., the working radius, and the rotation angle of the tower arm need to be known, and the coordinate position of the tower arm vector endpoint, i.e., the vertex of the tower arm, can be calculated.

[0085] Optionally, the first warning distance is calculated based on the personnel position coordinate, including:

[0086] The first warning distance is calculated based on the x-axis coordinate value and the y-axis coordinate value in the personnel position coordinate, and the following relationship is satisfied:

[0087] ;

[0088] In the formula, the first warning distance, the x-axis coordinate value of the personnel position coordinate, the y-axis coordinate value of the personnel position coordinate.

[0089] Optionally, the first warning distance is compared with a preset first threshold, and a first warning is given when the first warning distance is less than or equal to the preset first threshold, including:

[0090] A safety margin value is determined, and a sum of the tower arm working radius and the safety margin value is taken as the preset first threshold, and the first warning distance is compared with the preset first threshold;

[0091] When d1 , a first warning is given, and when d1 , no first warning is given, wherein d1 is the first warning distance, R is the tower arm working radius, is the safety margin value.

[0092] In the above embodiment, the safety margin value is an extended safety distance. When the first warning distance is greater than the tower arm working radius, it can be determined that the work of the tower arm will not affect the activities of the construction personnel, but in the face of complex construction site environment, the goods hoisted on the tower arm and other safety factors also need to be considered. Therefore, it is necessary to set a safety margin value, and the safety margin value cannot be too large or too small, otherwise it cannot play a good warning role. Under normal circumstances, the safety margin value can be set to 3 meters, and it can also be set to 5 meters when the tower crane hoists large goods. The setting of the safety margin value is determined according to the actual working condition of the tower crane.

[0093] Optionally, the second warning distance is calculated based on the personnel position coordinates, including:

[0094] The second warning distance is calculated based on the x-axis coordinate value and the y-axis coordinate value in the personnel position coordinates and the tower arm rotation angle, and the calculation satisfies the following relationship:

[0095] ;

[0096] ;

[0097] In the formula, is the second warning distance, is the x-axis coordinate value of the personnel position coordinates, is the y-axis coordinate value of the personnel position coordinates.

[0098] Optionally, the second warning distance is compared with a preset second threshold, and a second warning is given when the second warning distance is less than or equal to the preset second threshold, including:

[0099] The preset second threshold is determined , and the second warning distance is compared with the preset second threshold;

[0100] When d2 ≤ When the distance is less than the second threshold value, a secondary warning is given and the tower crane operation is automatically suspended, and when When the distance is less than the first threshold value, a primary warning is given.

[0101] In the above embodiment, the second threshold value is generally set to 5 meters during normal construction work, and can also be increased or decreased according to actual conditions. Unlike the primary warning condition, the secondary warning condition is applicable when the vertical distance between the construction personnel and the tower crane tower arm is less than the distance set in the false alarm prevention mechanism, so the danger level in the secondary warning condition is higher, the priority of the secondary warning is also higher compared to the primary warning, and the corresponding warning level is also more serious.

[0102] As shown in Figure 2 , the application embodiment also provides a tower crane operation safety active early warning system based on the Internet of Things, comprising a wearable terminal, a state acquisition unit, and a central processing platform.

[0103] The wearable terminal is used to acquire personnel position information of the construction personnel in real time, and send the personnel position information to the central processing platform.

[0104] The state acquisition unit is used to acquire tower crane state information of the tower crane in real time, and send the tower crane state information to the central processing platform.

[0105] The central processing platform is used to construct an early warning coordinate system with the tower crane rotation center as the origin, and map the personnel position information into the early warning coordinate system to obtain personnel position coordinates, map the tower crane state information into the early warning coordinate system to obtain tower arm vector endpoint coordinates, and is also used to calculate a primary warning distance based on the personnel position coordinates, compare the primary warning distance with a preset first threshold value, and give a primary warning when the primary warning distance is less than or equal to the preset first threshold value; calculate a secondary warning distance based on the personnel position coordinates, compare the secondary warning distance with a preset second threshold value, and give a secondary warning when the secondary warning distance is less than or equal to the preset second threshold value.

[0106] The central processing platform is also used to calculate a false alarm prevention distance according to the personnel position coordinates and the tower arm vector endpoint coordinates, and perform secondary warning distance calculation when the false alarm prevention distance meets the secondary warning calculation condition.

[0107] Optionally, the wearable terminal comprises a positioning module, a compensation module, and a voice broadcast unit.

[0108] The positioning module is used to acquire personnel position information of the construction personnel, and send the personnel position information to the compensation module.

[0109] The compensation module is used to compensate and correct the personnel position information, and send the compensated and corrected personnel position information to the central processing platform.

[0110] ​The voice broadcast unit is used to receive the first warning information sent by the central processing platform when the first warning is carried out and the second warning information sent by the central processing platform when the second warning is carried out, and to carry out the first warning reminding based on the first warning information and the second warning reminding based on the second warning information.

[0111] In the above embodiment, for the implementation of the first warning and the second warning, the central processing platform sends the corresponding implementation signal to the wearing terminal, and the wearing terminal warns the construction personnel.

[0112] When the first warning is carried out, the central processing platform sends the first warning signal to the wearing terminal, and the wearing terminal plays the warning voice of "You have entered the dangerous area, please pay attention to safety" according to the first warning signal to remind the construction personnel, and at the same time, the driver room of the tower crane flashes yellow warning light to warn the tower crane driver.

[0113] When the second warning is carried out, the central processing platform sends the second warning signal to the wearing terminal, and the wearing terminal plays the warning voice of "Danger below the boom, please evacuate quickly" according to the second warning signal to remind the construction personnel, and at the same time, the tower crane automatically suspends the operation and resumes when the second warning is stopped.

[0114] The above describes the preferred embodiments of the present application in detail. It should be understood that those skilled in the art can make many modifications and changes without creative labor according to the concept of the present application. Therefore, any technical solution obtained by logical analysis, reasoning or limited experiment based on the prior art according to the concept of the present application should be within the protection scope determined by the claims.

Claims

1. A tower crane operation safety active early warning method based on Internet of Things, characterized in that, The method comprises: constructing a pre-warning coordinate system with the center of the tower crane rotary as the origin, and obtaining personnel position information of the construction personnel, and mapping the personnel position information into the pre-warning coordinate system to obtain personnel position coordinates; obtaining tower crane state information of the tower crane, and determining a tower arm vector endpoint coordinate in the pre-warning coordinate system based on the tower crane state information; calculating a first warning distance based on the personnel position coordinates, comparing the first warning distance with a preset first threshold, and performing a first warning when the first warning distance is less than or equal to the preset first threshold; calculating a false-alarm-preventing distance based on the personnel position coordinates and the tower arm vector endpoint coordinate, and performing a second warning distance calculation when the false-alarm-preventing distance satisfies a second warning calculation condition; wherein the second warning distance calculation comprises: calculating a second warning distance based on the personnel position coordinates, comparing the second warning distance with a preset second threshold, and performing a second warning when the second warning distance is less than or equal to the preset second threshold; the specific steps of calculating the false-alarm-preventing distance comprise: before calculating the second warning distance, calculating the false-alarm-preventing distance based on the personnel position coordinates and the tower arm vector endpoint coordinate, and calculating to satisfy the following relationship: ； In the formula, D is a false judgment prevention distance, is an x-axis coordinate value of a personnel position coordinate, is an x-axis coordinate value of a tower arm vector end point coordinate, is a y-axis coordinate value of a personnel position coordinate, is a y-axis coordinate value of a tower arm vector end point coordinate. the second warning calculation condition comprises: comparing the false-alarm-preventing distance with a tower arm working radius in the tower crane state information; When 0 ≤ D ≤ R 2 , the secondary warning calculation condition is satisfied, and the secondary warning distance is calculated, and when D > R 2 , the secondary warning calculation condition is not satisfied, and the secondary warning distance is not calculated, where R is the tower arm working radius. 2.The IoT-based active pre-warning method for tower crane operation safety according to claim 1, characterized in that, the mapping of the personnel position information into the pre-warning coordinate system to obtain the personnel position coordinates comprises: constructing a mapping function between a geographic coordinate system and the pre-warning coordinate system, and mapping the personnel position information obtained based on the geographic coordinate system into the pre-warning coordinate system by using the mapping function to obtain an x-axis coordinate value and a y-axis coordinate value based on the pre-warning coordinate system; obtaining the personnel position coordinates based on the x-axis coordinate value and the y-axis coordinate value of the pre-warning coordinate system as the x-axis coordinate value and the y-axis coordinate value of the personnel position coordinates. 3.The IOT-based active pre-warning method for tower crane operation safety according to claim 1, characterized in that, the determination of the tower arm vector endpoint coordinate comprises: calculating the x-axis coordinate value of the tower arm vector endpoint coordinate and the y-axis coordinate value of the tower arm vector endpoint coordinate based on the tower arm rotation angle and the tower arm working radius in the tower crane state information, and calculating to satisfy the following relationship: ； ； wherein is the tower arm working radius, is the tower arm rotation angle, is the x-axis coordinate value of the tower arm vector endpoint coordinate, is the y-axis coordinate value of the tower arm vector endpoint coordinate; obtaining the tower arm vector endpoint coordinate based on the x-axis coordinate value and the y-axis coordinate value of the tower arm vector endpoint coordinate. 4.The IOT-based active early warning method for tower crane operation safety according to claim 1, characterized in that, the specific steps of calculating the first warning distance comprise: calculating the first warning distance based on the x-axis coordinate value and the y-axis coordinate value in the personnel position coordinates, and calculating to satisfy the following relationship: ； In the formula, is a first warning distance, is an x-axis coordinate value of the personnel position coordinate, is a y-axis coordinate value of the personnel position coordinate. 5.The IoT-based active pre-warning method for tower crane operation safety according to claim 4, characterized in that, the comparison of the first warning distance with the preset first threshold and the first warning when the first warning distance is less than or equal to the preset first threshold comprise: determining a safety margin value, taking the sum of the tower crane working radius and the safety margin value as the preset first threshold, and comparing the first warning distance with the preset first threshold; When a primary warning is given, and when a primary warning is not given, wherein d1 is a primary warning distance, R is a tower arm working radius, is a safety margin value. 6.The IOT-based active pre-warning method for tower crane operation safety according to claim 1, characterized in that, the specific steps of calculating the second warning distance comprise: calculating the second warning distance based on the x-axis coordinate value, the y-axis coordinate value in the personnel position coordinates, and the tower arm rotation angle, and calculating to satisfy the following relationship: ； ； wherein is a secondary warning distance, is an x-axis coordinate value of the person position coordinate, is a y-axis coordinate value of the person position coordinate, is a calculation intermediate variable, is a rotation angle. 7.The IoT-based active pre-warning method for tower crane operation safety according to claim 6, characterized in that, The comparing the secondary warning distance with a preset second threshold value and the secondary warning when the secondary warning distance is less than or equal to the preset second threshold value, comprises: determining a preset second threshold and comparing the secondary warning distance with a preset second threshold When ≤ a secondary warning is given and the tower crane operation is automatically suspended, when > no secondary warning is given.

8. A tower crane operation safety active early warning system based on Internet of Things, characterized in that, It comprises: Wearing terminal, state acquisition unit and central processing platform; The wearing terminal is used for acquiring personnel position information of the construction personnel in real time, and sending the personnel position information to the central processing platform; The state acquisition unit is used for collecting tower crane state information of the tower crane in real time, and sending the tower crane state information to the central processing platform; The central processing platform is used for constructing a warning coordinate system with the center of the tower crane rotation as the origin, mapping the personnel position information into the warning coordinate system to obtain personnel position coordinates, mapping the tower crane state information into the warning coordinate system to obtain tower arm vector endpoint coordinates, and is further used for calculating a first warning distance based on the personnel position coordinates, comparing the first warning distance with a preset first threshold value, and performing a first warning when the first warning distance is less than or equal to the preset first threshold value; calculating a secondary warning distance based on the personnel position coordinates, comparing the secondary warning distance with a preset second threshold value, and performing a secondary warning when the secondary warning distance is less than or equal to the preset second threshold value; The central processing platform is further used for calculating a false judgment prevention distance according to the personnel position coordinates and the tower arm vector endpoint coordinates, and performing secondary warning distance calculation when the false judgment prevention distance meets the secondary warning calculation condition; The specific steps of calculating the false judgment prevention distance, comprising: Before calculating the secondary warning distance, the false judgment prevention distance is calculated based on the personnel position coordinates and the tower arm vector endpoint coordinates, and the calculation meets the following relationship: ； In the formula, D is a false judgment prevention distance, is an x-axis coordinate value of a personnel position coordinate, is an x-axis coordinate value of a tower arm vector end point coordinate, is a y-axis coordinate value of a personnel position coordinate, is a y-axis coordinate value of a tower arm vector end point coordinate; The secondary warning calculation condition, comprising: Comparing the false judgment prevention distance with the tower arm working radius in the tower crane state information; When 0 ≤ D ≤ R 2 the secondary warning calculation condition is satisfied, and the secondary warning distance is calculated, and when D > R 2 the secondary warning calculation condition is not satisfied, and the secondary warning distance is not calculated, where R is the tower arm working radius. 9.The Internet of Things based active pre-warning system for tower crane operation safety according to claim 8, characterized in that, The wearing terminal comprises a positioning module, a compensation module and a voice broadcast unit; The positioning module is used for acquiring personnel position information of the construction personnel, and sending the personnel position information to the compensation module; The compensation module is used for compensating and correcting the personnel position information, and sending the compensated and corrected personnel position information to the central processing platform; The voice broadcast unit is used for receiving first warning information issued when the central processing platform performs a first warning and secondary warning information issued when the central processing platform performs a secondary warning, and performing a first warning reminder based on the first warning information and a secondary warning reminder based on the secondary warning information.

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