CN114266099B - Intelligent guiding and safety early warning method for road surface excavation operation coupled with underground pipe network BIM model - Google Patents

Abstract

The present invention relates to an intelligent guidance and safety warning method for road excavation operation coupled with an underground pipe network BIM model, which aims to make up for the deficiencies of the existing intelligent guidance system for excavators. According to the characteristics of road excavation operation, an intelligent guidance device for excavators is used, coupled with an underground pipe network BIM model, and an intelligent guidance and safety warning method for road excavation operation is proposed, which can simultaneously realize the three-dimensional visualization of the BIM model of the underground pipe network and the excavator on the vehicle side and the client side, intuitively guide the operator to perform the excavation operation, and can perform multi-level safety warnings on the road excavation operation to prevent the excavator bucket from colliding with the underground pipe network. Compared with the existing intelligent guidance technology for excavators, it can not only realize the visual guidance of road excavation operation, but also has a unique multi-level safety warning and anti-collision function.

Description

An intelligent guidance and safety warning method for road excavation operations coupled with an underground pipe network BIM model

Technical Field

The present invention belongs to the field of municipal road engineering, and relates to road engineering excavation operation technology, in particular to an intelligent guidance and safety early warning method for road excavation operation coupled with an underground pipe network BIM model.

Background Art

With the development of urban industrialization and informatization, many infrastructure facilities need to be rebuilt or renovated, which involves a large number of road excavation operations under dense underground pipe networks. Urban road excavation operations may cause damage to underground pipes and cables in the city, resulting in loss of life and property; in addition, excavation operations are easily affected by human factors, and quality control during the process mainly depends on the operator's operating level and on-site supervision, making it difficult to ensure construction safety and quality.

At present, there is intelligent guidance technology for excavators, which realizes real-time perception and monitoring of the construction posture of the excavator, can guide the operator to perform precise excavation operations, and improve the construction quality and efficiency. However, there is a lack of effective means to convey the location information of the underground pipeline network to the operator. The operator cannot see the location of the underground pipeline network and it is difficult to control the relative distance between the excavator shovel tip and the underground pipeline network, which can easily cause collision accidents. Therefore, it is necessary to perceive the location information of the underground pipeline network in real time during the excavation operation through the predetermined underground pipeline network location, and judge the relative distance between the excavator shovel tip and the underground pipeline network in real time, so as to improve the safety of road excavation operations and reduce the occurrence of safety accidents.

Summary of the invention

In order to solve the problems that the current excavation operation of excavators is greatly affected by human factors, the quality is difficult to control, and the safety of underground pipe networks is threatened, the present invention proposes an intelligent guidance and safety warning method for road excavation operations coupled with the BIM model of underground pipe networks. Relying on advanced positioning technology and posture perception technology, and coupled with the BIM model of underground pipe networks, the present invention realizes intelligent guidance and real-time safety warning of road excavation operations, which is of great significance to improving the accuracy, efficiency and safety of excavation operations.

The present invention solves the technical problem by adopting the following technical solutions:

A method for intelligent guidance and safety warning of road excavation operations coupled with an underground pipe network BIM model comprises the following steps: (1) a user logs in to a monitoring client; (2) a BIM model of an underground pipe network and an excavator in a site is established and uploaded; (3) an excavation task is created, an excavator ID is input, and a multi-level safety warning zone is set according to the distance between the shovel tip and the pipeline; (4) an excavator dispatch instruction is issued on the monitoring client; (5) a database and an application server receive and store excavation task information, BIM model information, and excavator dispatch instructions; (6) an on-board terminal is turned on to receive excavation task information and download and update the BIM model; (7) a GNSS antenna collects excavator positioning information; (8) an inclination sensor is installed on the excavator, and the inclination information of the excavator mechanical components is collected by using the inclination sensor. The specific method is as follows:

Four inclination sensors are installed on the excavator to collect the inclination information of the excavator's mechanical components. Three of them are single-axis inclination sensors, which are installed on the boom, arm and bucket respectively, and are used to collect the longitudinal inclination angles of the boom, arm and bucket. The other inclination sensor is a dual-axis inclination sensor, which is installed under the boom of the excavator's main chassis to determine the longitudinal and lateral inclination angles of the excavator body. The collected inclination information of the excavator's mechanical components is transmitted to the vehicle-mounted terminal in real time for subsequent calculation and processing;

(9) Real-time solution of the excavator shovel tip coordinates. The specific method is as follows:

The vehicle-mounted terminal receives the excavator positioning data collected by the GNSS antenna and the excavator mechanical component inclination data collected by the sensor in real time. Combined with the excavator's own model and mechanical size, its analysis and calculation module solves the three-dimensional spatial coordinates of the excavator's shovel tip in real time. The mechanical parameters that need to be measured are: main antenna positioning coordinates _G1 ( _X1 , _Y1 , _Z1 ), auxiliary antenna positioning coordinates _G2 , the position of the boom fulcrum in the vehicle coordinate system ( _xd , _yd , _zd ), boom length _L1 , arm length _L2 , bucket length _L3 , bucket width _L4 , vehicle body lateral inclination angle ζ, vehicle body longitudinal inclination angle φ, boom longitudinal inclination angle _θ1 , arm longitudinal inclination angle _θ2 and bucket longitudinal inclination angle _θ3 . The coordinates of the excavator's shovel tip are obtained by the excavator's positioning coordinates _G1 , _G2 , excavator mechanical component sizes and excavator working posture control parameters (ζ, φ, _θ1 , _θ2 , _θ3 ) calculated,

The coordinates of the midpoint of the bottom edge of the excavator blade in the vehicle coordinate system are:

x _in = x _d

y_中＝y _d +L ₁ sinθ ₁ +L ₂ sin(θ ₁ +θ ₂ )+L ₃ sin(θ ₁ +θ ₂ +θ ₃ )

z_中＝z _d +L ₁ cosθ ₁ +L ₂ cos(θ ₁ +θ ₂ )+L ₃ cos(θ ₁ +θ ₂ +θ ₃ )

The coordinates of the left shovel tip of the excavator in the vehicle coordinate system are:

_yleft ＝y _d +L ₁ sinθ ₁ +L ₂ sin(θ ₁ +θ ₂ )+L ₃ sin(θ ₁ +θ ₂ +θ ₃ )

_zleft ＝ _zd +L ₁ cosθ ₁ +L ₂ cos(θ ₁ +θ ₂ )+L ₃ cos(θ ₁ +θ ₂ +θ ₃ )

The coordinates of the left shovel tip of the excavator in the work area coordinate system are:

K is the rotation matrix obtained by applying the Euler formula, where φ is the longitudinal tilt angle of the vehicle body, ζ is the lateral tilt angle of the vehicle body, obtained by the dual-axis tilt sensor, is the angle between the vehicle body and the north direction, which is calculated by _G1 and _G2 .

Similarly, the coordinates of the right shovel tip of the excavator in the work area coordinate system can also be calculated;

(10) Real-time calculation of the minimum spatial distance S between the excavator tip and the underground pipe network BIM model. The specific method is as follows:

The safety warning module of the vehicle terminal determines the pipeline segment to which the current working position of the excavator belongs based on the work area coordinates of the excavator's GNSS positioning, calls the BIM model of the underground pipeline network of the three segments closest to the current working position of the excavator, and calculates the pipeline distance. The spatial straight line equation determined by the start and end coordinates A (x ₁ , y ₁ , z ₁ ) and B (x ₂ , y ₂ , z ₂ ) of the central axis of the pipeline segment is:

The vector (m,n,p) is the direction vector of line AB.

The coordinates of the foot of the perpendicular D can be obtained by using the coordinates C (x _left , y _left , z _left ) of the left shovel tip of the excavator and the straight line AB. The equation of the straight line AB and the equation of the plane perpendicular to the straight line AB can be solved by combining m(xx _left )+n(yy _left )+p(zz _left )=0. The coordinates of D are (mk+x ₁ ,nk+y ₁ ,pk+z ₁ ), where:

Then the distance from the left shovel tip coordinate C to the straight line AB is:

If the foot of the perpendicular D is located on the line segment AB, the relative distance between the left shovel tip C of the excavator and the BIM model of the pipeline is:

R＝CD-r

If the foot of the perpendicular D is on the extension line of the line segment AB, then R is the minimum distance from the left shovel tip C of the excavator to the outer wall of the pipe end points A and B, and r is the radius of the pipe;

The minimum spatial distance between the left shovel tip C of the excavator and the BIM model of all pipelines in the underground pipe network is:

_Sleft ＝min R _i i＝1,2,3…M

Where M is the number of pipelines contained in the current working area;

Similarly, the minimum spatial distance _Sright , _Sleft and _Sright between the right shovel tip of the excavator and the BIM model of all pipelines in the three partitions can be obtained, which is the minimum spatial distance S between the shovel tip of the excavator and the BIM model of the underground pipe network.

(11) Safety distance determination, multi-level safety warning and automatic braking. The specific methods are as follows:

The safety warning module of the vehicle terminal compares the real-time calculated relative distance S between the excavator shovel tip and the underground pipe network BIM model with the set multi-level safety warning distances S _low and S _high . When S>S _low , it indicates that the excavator shovel tip is in the safe zone; when S _high <S <S _low , it indicates that the excavator shovel tip has entered the low-risk warning zone, and the operator is reminded by voice to be careful during construction; when S <S _high , it indicates that the excavator shovel tip has entered the high-risk warning zone, and the excavator bucket will automatically stop to avoid collision between the excavator shovel tip and the pipeline due to the operator's failure to stop the car in time;

(12) Visual display of vehicle terminal;

(13) The database and application server receive the data sent back by the vehicle terminal, analyze and store it;

(14) Monitor client visual display, remote real-time monitoring and query statistics.

Furthermore, in step (1), the developed monitoring client is logged in and the user rights are verified. The user rights include browsing, operation and management. The browsing user can realize visual remote real-time monitoring, query and receive alarm information and other functions; the operating user can create excavation tasks based on the browsing user rights, including inputting the excavator ID, setting multi-level safety warning areas, uploading the underground pipe network and excavator BIM model of the site and issuing excavator dispatch instructions and other functions; the management user, in addition to having the rights of the above two types of users, is responsible for managing the rights of other users.

Moreover, the establishment and uploading of the underground pipe network and excavator BIM model in the site in step (2) includes: obtaining the location information of the underground pipe network in the site through a pipeline avoidance instrument or a ground penetrating radar, and correcting the underground pipe network location data in combination with the underground pipe network construction organization design CAD drawings to obtain accurate underground pipe network location information. The site is divided into different sections according to a certain pipeline length, and the pipelines across the sections and the pipeline turns are cut and processed, and the pipelines are expressed as cylinders determined by the starting coordinates of the central axis and the pipe diameter; the pipelines are numbered and bound to the sections to which they belong, the starting coordinates of the pipeline central axis and the pipeline radius, so as to establish the underground pipe network BIM model; the size parameters of each mechanical component of the on-site construction excavator are measured to establish the excavator BIM model.

Moreover, step (3) of creating an excavation task on the monitoring client includes: setting the start and end segments and start and end times of the task and inputting the excavator ID corresponding to the current task; at the same time, according to the distance between the shovel tip and the pipeline, setting multiple levels of safety warning zones, from far to near, namely, the safety zone, the low-risk warning zone and the high-risk warning zone.

Moreover, in step (4), the operating user issues an excavator dispatch instruction on the monitoring client, reminding the on-site construction management personnel to receive the excavator dispatch information by text message, and arrange the excavator operator to perform the excavation operation; at the same time, the database and application server only receive the data sent back by the vehicle-mounted terminal during the excavator dispatch time period. The operating user can issue an end dispatch instruction to terminate the on-site excavation operation according to the completion status of the excavation task.

Moreover, the database and application server receive the excavation task information created by the monitoring client, the uploaded BIM model of the excavator and the underground pipe network in the site, and the issued excavator dispatch instruction, and store the above information in the database module of the database and application server; after receiving the excavator dispatch instruction, the on-site manager arranges the excavator operator to perform the excavation operation, the excavator operator turns on the vehicle-mounted terminal in the cab, the vehicle-mounted terminal receives the corresponding excavation task information from the database and application server, and automatically checks whether the excavator model and the underground pipe network model have changed. If there is a change, the vehicle-mounted terminal automatically downloads and updates the corresponding BIM model. If there is no change, the excavation operation is performed according to the BIM model used in the last excavation; a differential base station is established at the construction site, a GNSS positioning antenna is installed on the excavator, and the GNSS-RTK positioning technology is used to collect the excavator coordinate information in real time. The main positioning antenna is used to determine the three-dimensional spatial coordinate position of the excavator, and the auxiliary positioning antenna cooperates with the main positioning antenna to determine the direction angle of the excavator. The collected excavator positioning information is transmitted to the vehicle-mounted terminal in real time for subsequent calculation and processing.

Moreover, the intelligent guidance module of the vehicle-mounted terminal in step (12) visualizes the on-site excavation operation and guides the excavator operator to work safely, mainly including the three-dimensional visualization display of the BIM model and the real-time display of data. The vehicle-mounted terminal determines the current working position based on the GNSS positioning information of the excavator, and automatically retrieves the BIM model of the underground pipeline network within a certain range of the excavator; based on the inclination data of the excavator mechanical components collected by the inclination sensor, a three-dimensional dynamic display of each mechanical component of the excavator BIM model is realized; the shovel tip can be partially enlarged and displayed, and the shovel tip and the nearest underground pipeline can be connected in real time with a red line to enhance the visualization effect of the excavation operation.

Moreover, the data received by the database and application server of step (13) from the vehicle terminal mainly include: GNSS positioning data, inclination sensor data, shovel tip coordinate data, relative distance data between shovel tip coordinate and underground pipe network and on-site alarm data; the analysis and calculation module of the database and application server uses the GNSS positioning data to draw the working position trajectory of the excavator in real time in three dimensions; uses the inclination sensor data to display the three-dimensional dynamic model of the excavator BIM model on the monitoring client in real time; uses the shovel tip coordinate data to draw the shovel tip trajectory of the excavator in real time in three dimensions, and generates a thermal cloud map of the excavation operation to reflect the on-site construction situation; uses the relative distance data between the shovel tip coordinate and the underground pipe network to monitor the relative distance of the on-site excavation operation in real time; uses the on-site alarm data to display the safety warning situation on the monitoring client, which mainly includes the alarm time, the number and location of the dangerous underground pipeline at the time of the alarm, the shovel tip coordinate at the time of the alarm and the alarm picture information.

Moreover, the data displayed in step (14) mainly include the excavator working position data, the shovel tip coordinate data and the relative distance data; the excavator working position trajectory, the excavator shovel tip trajectory and the excavation operation thermal cloud map can be drawn in real time in three dimensions, thereby realizing remote real-time monitoring of the excavation construction site; at the same time, the monitoring client can query and count the on-site excavation operation results from the database and the database module of the application server, playback and browse the trajectory and graphics and output them in the form of video or chart, so as to facilitate the subsequent safety assessment of the entire excavation construction process.

The advantages and positive effects of the present invention are:

The present invention aims to make up for the shortcomings of the existing intelligent guidance system for excavators. Aiming at the problem that the underground pipe network is invisible and the relative distance is difficult to control during road excavation operations, a road excavation operation intelligent guidance and safety warning method coupled with the underground pipe network BIM model is proposed. The spatial relative distance between the excavator shovel tip and the underground pipe network BIM model can be quickly calculated in real time to achieve three-dimensional visualization and intelligent guidance of road excavation operations; different levels of safety warning zones can be set according to the distance between the shovel tip and the underground pipe network to achieve multi-level safety warning for excavation operations; and when the excavator shovel tip enters the high-risk warning zone, the excavator bucket can be automatically stopped to avoid safety accidents caused by the operator's untimely parking (or bucket avoidance); the present invention is coupled with the underground pipe network BIM model. Compared with the existing intelligent guidance technology for excavators, it can not only achieve visual guidance of road excavation operations, but also has a unique multi-level safety warning and anti-collision function.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a system connection diagram of the present invention;

FIG2 is a flow chart of the steps of the method of the present invention;

3 is a schematic diagram of the installation position of the single-axis tilt sensor of the present invention;

FIG4 is a schematic diagram of a shovel tip coordinate solution algorithm of the present invention;

FIG5 is a schematic diagram of an algorithm for solving the spatial relative distance between the shovel tip and the pipeline BIM model of the present invention.

DETAILED DESCRIPTION

The present invention is further described in detail below through specific examples. The following examples are only illustrative and not restrictive, and the protection scope of the present invention cannot be limited thereto.

The present invention aims to make up for the shortcomings of the existing intelligent guidance system of excavators. According to the characteristics of road excavation operations, the present invention utilizes the intelligent guidance device of the excavator and couples the BIM model of the underground pipe network to propose an intelligent guidance and safety warning method for road excavation operations. The method can synchronously realize the three-dimensional visualization of the BIM model of the underground pipe network and the excavator on the vehicle side and the client side, and intuitively guide the operator to perform excavation operations. The method can perform multi-level safety warnings on road excavation operations to prevent the collision of the excavator bucket and the underground pipe network.

In order to achieve the above-mentioned purpose, the system for realizing the method of the present invention is shown in Figure 1, which is specifically composed of three parts: a monitoring client, a database and application server, and a vehicle-mounted terminal. The main functions of the monitoring client are to create tasks, upload BIM models, dispatch excavators, remote real-time monitoring, and query statistics. The main functions of the database and application server are to store, analyze, and transmit data, which specifically include three modules: a database module, an analysis and calculation module, and an information feedback module. The vehicle-mounted terminal is composed of a GNSS receiver, a tilt sensor, and a vehicle-mounted terminal. The function of the GNSS receiver is to locate the working position of the excavator and obtain the heading angle of the excavator; the function of the tilt sensor is to obtain the working posture of the excavator; the vehicle-mounted terminal is used to analyze and calculate the GNSS positioning data and the tilt sensor data, and to provide intelligent guidance and safety warning for on-site construction, which specifically includes three modules: analysis and calculation, intelligent guidance, and safety warning.

The method steps of the present invention include: logging in to the developed monitoring client, uploading the pre-established underground pipe network and excavator BIM model of the construction site, creating a road excavation task, entering the excavator ID, and setting a multi-level safety warning zone according to the distance between the shovel tip and the pipeline, and issuing an excavator dispatch instruction; the above information is stored in the database and the database module of the application server through the Internet network. The vehicle-mounted terminal is turned on, and the database and application server are accessed through the 5G (The 5th Generation mobilecommunication technology) communication method, and the corresponding task information is received from its database module and the BIM model of the underground pipe network and the excavator is downloaded and updated. The GNSS-RTK (Global Navigation Satellite System–Real-time Kinemics, Global Navigation Satellite System-Dynamic Real-time Differential) positioning technology is used to obtain the working position information of the excavator, and the inclination information of each component of the excavator is obtained by using an inclination sensor. The analysis and calculation module of the vehicle-mounted terminal receives the GNSS positioning information and sensor information of the excavator, and calculates the spatial coordinates of the excavator shovel tip in combination with the mechanical dimensions of the excavator. The safety warning module of the vehicle terminal calculates the spatial relative position of the excavator shovel tip and the underground pipe network BIM model in real time, and judges it with the set multi-level safety warning distance. If the excavator shovel tip enters the low-risk warning area, an on-site voice alarm will be issued; if the excavator shovel tip enters the high-risk warning area, the excavator will automatically brake to avoid the operator's failure to stop (or bucket avoidance) in time and cause a safety collision accident. The intelligent guidance module of the vehicle terminal displays the BIM model of the underground pipe network and the excavator in real time, intelligently guides the operator to operate accurately, and displays the relative distance between the excavator shovel tip and the underground pipe network. The database and application server receive the information sent back by the excavator vehicle terminal in real time (including GNSS-RTK positioning information, shovel tip coordinate information, relative distance information and safety warning brake information), and its analysis and calculation module analyzes and processes the above information, and the database module stores the analysis results and data information. At the same time, the monitoring client reads the results of the analysis and processing of the database and application server from the information feedback module in real time, displays the BIM model of the underground pipe network and the excavator in three dimensions, and remotely monitors the on-site excavation operation in real time. When the mining task is completed, the monitoring client can access the database and the database module of the application server to query the statistics of the construction process.

The specific implementation steps of the method of the present invention are shown in Figure 2, which include the following steps:

(1) After passing the verification, the user logs in to the monitoring client.

Log in to the developed monitoring client and verify the user rights, which include browsing, operation and management. Browsing users can realize visual remote real-time monitoring, query and receive alarm information; operating users can create excavation tasks (enter excavator ID, set multi-level safety warning areas), upload the underground pipe network and excavator BIM model of the site and issue excavator dispatch instructions based on the browsing user rights; management users, in addition to the rights of the above two types of users, are responsible for managing the rights of other users.

(2) Establish and upload the BIM model of the underground pipeline network and excavator in the construction site.

The location information of the underground pipeline network in the site is obtained through pipeline avoidance instruments or ground penetrating radars, and the underground pipeline network location data is corrected in combination with the CAD drawings of the underground pipeline network construction organization design to obtain accurate underground pipeline network location information; the site is divided into different sections according to a certain pipeline length, and the pipelines across the sections and the pipeline bends are cut, and the pipelines are expressed as cylinders determined by the starting coordinates of the central axis and the pipe diameter; the pipelines are numbered and bound to the sections to which they belong, the starting coordinates of the pipeline central axis and the pipeline radius, so as to establish the underground pipeline network BIM model; the dimensional parameters of each mechanical component of the on-site construction excavator are measured to establish the excavator BIM model.

(3) Create an excavation task on the monitoring client, enter the excavator ID, and set a multi-level safety warning zone based on the distance between the shovel tip and the pipeline.

Create an excavation task on the monitoring client, including setting the start and end segments of the task, the start and end time, and entering the excavator ID corresponding to the current task. At the same time, set multi-level safety warning zones according to the distance between the shovel tip and the pipeline, from far to near, respectively, the safety zone, low-risk warning zone and high-risk warning zone, which are used to subsequently determine the spatial area where the excavator shovel tip is located.

(4) Issue excavator dispatch instructions on the monitoring client.

The operating user issues an excavator dispatch instruction on the monitoring client, reminds the on-site construction management personnel to receive the excavator dispatch information by SMS, and arranges the excavator operator to perform the excavation operation; at the same time, the database and application server only receive the data sent back by the vehicle terminal during the excavator dispatch time period. The operating user can issue an end dispatch instruction to terminate the on-site excavation operation according to the completion of the excavation task.

(5) The database module of the database and application server receives and stores mining task information, BIM model information and excavator dispatch instructions.

The database and application server receive the excavation task information created by the monitoring client, the uploaded BIM model of the excavator and the underground pipe network in the site, and the issued excavator dispatch instructions, and store the above information in the database module of the database and application server.

(6) The vehicle terminal is turned on to receive mining task information from the database and application server and download and update the BIM model.

After receiving the excavator dispatch instruction, the on-site manager arranges the excavator operator to perform the excavation operation. The excavator operator turns on the vehicle-mounted terminal in the cab, which receives the corresponding excavation task information from the database and application server, and automatically checks whether the excavator model and underground pipe network model have changed. If there is a change, the vehicle-mounted terminal automatically downloads and updates the corresponding BIM model; if there is no change, the excavation operation is performed according to the BIM model used in the last excavation.

(7) Establish a differential base station at the construction site, install a GNSS positioning antenna on the excavator, and use GNSS-RTK positioning technology to collect the excavator coordinate information in real time.

A differential base station is established at the construction site, and a GNSS positioning antenna is installed on the excavator. The GNSS-RTK positioning technology is used to collect the coordinate information of the excavator in real time. The main positioning antenna is used to determine the three-dimensional spatial coordinate position of the excavator; the auxiliary positioning antenna cooperates with the main positioning antenna to determine the direction angle of the excavator. The collected excavator positioning information is transmitted to the vehicle terminal in real time for subsequent calculation and processing.

(8) Install an inclination sensor on the excavator to collect inclination information of the excavator's mechanical components. The specific method is as follows:

The tilt information of the excavator mechanical components is collected through four tilt sensors, of which three are single-axis tilt sensors, with installation positions shown in Figure 3, which are used to determine the longitudinal tilt angles of the boom, dipper and bucket respectively; the other is a dual-axis tilt sensor, which is installed on the chassis of the excavator mainframe (below the boom) to determine the longitudinal and lateral tilt angles of the excavator body. The collected tilt information of the excavator mechanical components is transmitted to the vehicle-mounted terminal in real time for subsequent calculation and processing.

(9) The analysis and calculation module of the vehicle terminal solves the coordinates of the excavator tip in real time. The specific method is as follows:

The vehicle-mounted terminal receives the excavator positioning data collected by the GNSS antenna and the excavator mechanical component inclination data collected by the inclination sensor in real time. Its analysis and calculation module analyzes the excavator movement, and the position of the shovel tip coordinates depends on the mechanical size parameters and inclination of each component of the excavator. When the length and inclination of each component of the excavator are determined, the shovel tip coordinates are correspondingly located at a certain position. The mechanical parameters that need to be measured are: main antenna positioning coordinates _G1 ( _X1 , _Y1 , _Z1 ), auxiliary antenna positioning coordinates _G2 , the position of the boom fulcrum in the vehicle coordinate system ( _xd , _yd , _zd ), boom length _L1 , arm length _L2 , bucket length _L3 , bucket width _L4 , vehicle body lateral inclination angle ζ, vehicle body longitudinal inclination angle φ, boom longitudinal inclination angle _θ1 , arm longitudinal inclination angle _θ2 and bucket longitudinal inclination angle _θ3 . The excavator shovel tip coordinates are calculated from the excavator positioning coordinates _G1 , _G2 , the dimensions of the excavator mechanical components and the excavator working posture control parameters (ζ, φ, _θ1 , _θ2 , _θ3 ). Figure 4 is a schematic diagram of the shovel tip coordinate solution algorithm.

The coordinates of the midpoint of the bottom edge of the excavator blade in the vehicle coordinate system are:

x _in = x _d

y_中＝y _d +L ₁ sinθ ₁ +L ₂ sin(θ ₁ +θ ₂ )+L ₃ sin(θ ₁ +θ ₂ +θ ₃ )

z_中＝z _d +L ₁ cosθ ₁ +L ₂ cos(θ ₁ +θ ₂ )+L ₃ cos(θ ₁ +θ ₂ +θ ₃ )

The coordinates of the left shovel tip of the excavator in the vehicle coordinate system are:

_yleft ＝y _d +L ₁ sinθ ₁ +L ₂ sin(θ ₁ +θ ₂ )+L ₃ sin(θ ₁ +θ ₂ +θ ₃ )

_zleft ＝ _zd +L ₁ cosθ ₁ +L ₂ cos(θ ₁ +θ ₂ )+L ₃ cos(θ ₁ +θ ₂ +θ ₃ )

The coordinates of the left shovel tip of the excavator in the work area coordinate system are:

K is the rotation matrix obtained by applying the Euler formula, where φ is the longitudinal tilt angle of the vehicle body, ζ is the lateral tilt angle of the vehicle body, obtained by the dual-axis tilt sensor, It is the angle between the vehicle body and the north direction, calculated by _G1 and _G2 .

Similarly, the coordinates of the right shovel tip of the excavator in the work area coordinate system can also be calculated.

(10) The safety warning module of the vehicle terminal calculates the minimum spatial distance S between the excavator tip and the underground pipe network BIM model in real time. The specific method is as follows:

The safety warning module of the vehicle terminal determines the pipeline segment to which the excavator's current working position belongs based on the work area coordinates of the excavator's GNSS positioning, and calls the underground pipeline network BIM model of the three segments closest to the excavator's current working position for calculation. Taking a pipeline as an example to illustrate the algorithm calculation, Figure 5 is a schematic diagram of the algorithm for solving the spatial relative distance between the shovel tip and the pipeline BIM model.

The equation of the space line determined by the starting and ending coordinates of the centerline of this section of pipeline, A (x ₁ , y ₁ , z ₁ ) and B (x ₂ , y ₂ , z ₂ ), is:

The vector (m,n,p) is the direction vector of line AB.

The coordinates of the foot of the perpendicular D can be obtained by using the coordinates C (x _left , y _left , z _left ) of the left shovel tip of the excavator and the straight line AB. The equation of the straight line AB and the equation of the plane perpendicular to the straight line AB can be solved by combining m(xx _left )+n(yy _left )+p(zz _left )=0. The coordinates of D are (mk+x ₁ ,nk+y ₁ ,pk+z ₁ ), where:

Then the distance from the left shovel tip coordinate C to the straight line AB is:

If the foot of the perpendicular D is located on the line segment AB, as shown in Figure 5(a), the relative distance between the left shovel tip C of the excavator and the BIM model of the pipeline is:

R＝CD-r

If the foot of the perpendicular D is on the extension line of the line segment AB, as shown in Figure 5(b), then R is the minimum value of the distance from the left shovel tip C of the excavator to the outer wall of the pipe end points A and B:

Where r is the radius of the pipe.

The minimum spatial distance between the left shovel tip C of the excavator and the BIM model of all pipelines in the underground pipe network is:

_Sleft ＝min R _i i＝1,2,3…M

Where M is the number of pipelines contained in the current working area.

Similarly, the minimum spatial distance _Sright , _Sleft and _Sright between the right shovel tip of the excavator and the BIM model of all pipelines in the three partitions can be obtained, which is the minimum spatial distance S between the right shovel tip of the excavator and the BIM model of the underground pipeline network.

(11) Safety distance determination, multi-level safety warning and automatic braking. The specific methods are as follows:

The safety warning module of the vehicle terminal compares the real-time calculated relative distance S between the excavator shovel tip and the underground pipe network BIM model with the set multi-level safety warning distances S _low and S _high to determine the current spatial area where the excavator shovel tip is located. When S>S _low , it indicates that the excavator shovel tip is in the safe area and the excavator is in a safe working state; when S _high <S <S _low , it indicates that the excavator shovel tip has entered the low-risk warning area, and the voice reminds the operator to be careful in construction; when S <S _high , it indicates that the excavator shovel tip has entered the high-risk warning area, and the excavator bucket will automatically stop at this time to avoid the operator's failure to stop in time and cause the excavator shovel tip to collide with the pipeline. The automatic parking function can be selected on the display screen of the vehicle terminal. If it is turned on, according to the signal output by the safety warning module of the vehicle terminal, the electronic valve switch on the excavator controls the opening of the brake line, and the brake fluid enters the brake connected to each hydraulic cylinder through the brake line, thereby realizing the braking of the excavator and its shovel tip; if it is not turned on, the brake valve can be manually operated to control the bucket to stop or move away to avoid.

(12) The intelligent guidance module of the vehicle terminal provides a real-time three-dimensional visualization of the BIM model of the underground pipeline network and the excavator, guiding the operator to perform precise operations and displaying the relative distance between the excavator shovel tip and the underground pipeline network.

The intelligent guidance module of the vehicle terminal visualizes the on-site excavation operation and guides the excavator operator to construct safely. It mainly includes the three-dimensional visualization display of the BIM model and the real-time display of data. The vehicle terminal determines the current working position according to the GNSS positioning information of the excavator, and automatically retrieves the BIM model of the underground pipe network within a certain range of the excavator; according to the inclination data of the excavator mechanical components collected by the inclination sensor, the three-dimensional dynamic display of each mechanical component of the excavator BIM model is realized; the shovel tip part can be partially enlarged and displayed, and the shovel tip and the nearest underground pipeline are connected in real time with a red line to enhance the visualization effect of the excavation operation. The real-time display of the data on the vehicle terminal display screen is mainly the display of the relative distance between the left and right shovel tips of the excavator and the underground pipe network. At the same time, according to the set multi-level safety warning distance, a relative distance display meter is developed (such as 0-30cm is red; 30-50cm is yellow; 50cm and above is green), and the pointer position is the relative distance between the coordinates of the excavator shovel tip and the underground pipe network.

(13) The database and application server receive the data sent back by the vehicle terminal and analyze and store it.

The database and application server receive data sent back by the vehicle terminal, mainly including GNSS positioning data, inclination sensor data, shovel tip coordinate data, shovel tip coordinate relative distance data and underground pipe network, and on-site alarm data. The analysis and calculation module of the database and application server uses GNSS positioning data to draw the working position trajectory of the excavator in real time in three dimensions; uses inclination sensor data to display the excavator BIM model in three dimensions on the monitoring client in real time; uses shovel tip coordinate data to draw the shovel tip trajectory of the excavator in real time in three dimensions, and generates a thermal cloud map of the excavation operation to reflect the on-site construction situation; uses the shovel tip coordinate relative distance data and underground pipe network to monitor the relative distance of the on-site excavation operation in real time; uses on-site alarm data to display the safety warning situation on the monitoring client, mainly including the alarm time, the number and location of the dangerous underground pipeline at the time of alarm, the shovel tip coordinate at the time of alarm, and the alarm picture. The information feedback module of the database and application server sends the analyzed and processed data information to the monitoring client in real time. The database module of the database and application server stores the above data and analysis and processing results for subsequent query and statistics.

(14) Monitor client visual display, remote real-time monitoring and query statistics.

The monitoring client receives data information from the database and application server information feedback module in real time, displays the underground pipe network and excavator BIM model in three-dimensional visualization, and has basic functions such as scaling, rotating, hiding, and displaying the BIM model; the displayed data mainly includes the excavator working position data, shovel tip coordinate data, and relative distance data; it can draw the excavator working position trajectory, the excavator shovel tip trajectory, and the excavation operation thermal cloud map in real time, thereby realizing remote real-time monitoring of the excavation construction site. At the same time, the monitoring client can query and count the on-site excavation operation results from the database and the database module of the application server, playback and browse the trajectory and graphics, and output them in the form of video or charts, which is convenient for subsequent safety assessment of the entire excavation construction process.

Although the embodiments of the present invention are disclosed for illustrative purposes, those skilled in the art will appreciate that various substitutions, changes and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments.

Claims (9)

1. A method for intelligent guidance and safety warning of road excavation operations coupled with an underground pipe network BIM model, characterized in that: The method comprises the following steps: (1) Log in to the monitoring client; (2) Establish and upload the BIM model of the underground pipe network and excavator in the site. To facilitate the subsequent model retrieval and calculation, the BIM model of the underground pipe network is divided into sections according to certain pipe lengths; (3) Create an excavation task, enter the excavator ID, and set multiple levels of safety warning zones according to the distance between the shovel tip and the pipeline, from far to near, including the safety zone, low-risk warning zone, and high-risk warning zone; (4) Issue excavator dispatch instructions on the monitoring client; (5) The database and application server receive and store mining task information, BIM model information, and excavator dispatch instructions; (6) The vehicle terminal is turned on to receive excavation task information and download and update the BIM model; (7) Collecting excavator positioning information using the Global Navigation Satellite System (GNSS) antenna; (8) Install an inclination sensor on the excavator and use the inclination sensor to collect inclination information of the excavator's mechanical components. The specific method is as follows: Four inclination sensors are installed on the excavator to collect the inclination information of the excavator's mechanical components. Three of them are single-axis inclination sensors, which are installed on the boom, arm and bucket respectively, and are used to collect the longitudinal inclination angles of the boom, arm and bucket. The other inclination sensor is a dual-axis inclination sensor, which is installed under the boom of the excavator's main chassis to determine the longitudinal and lateral inclination angles of the excavator body. The collected inclination information of the excavator's mechanical components is transmitted to the vehicle-mounted terminal in real time for subsequent calculation and processing; (9) Real-time solution of the excavator shovel tip coordinates. The specific method is as follows: The vehicle-mounted terminal receives the excavator positioning data collected by the GNSS antenna and the excavator mechanical component inclination data collected by the sensor in real time. Combined with the excavator's own model and mechanical size, its analysis and calculation module solves the three-dimensional spatial coordinates of the excavator's shovel tip in real time. The mechanical parameters that need to be measured are: main antenna positioning coordinates _G1 ( _X1 , _Y1 , _Z1 ), auxiliary antenna positioning coordinates _G2 , the position of the boom fulcrum in the vehicle coordinate system ( _xd , _yd , _zd ), boom length _L1 , arm length _L2 , bucket length _L3 , bucket width _L4 , vehicle body lateral inclination angle ζ, vehicle body longitudinal inclination angle φ, boom longitudinal inclination angle _θ1 , arm longitudinal inclination angle _θ2 and bucket longitudinal inclination angle _θ3 . The coordinates of the excavator's shovel tip are obtained by the excavator's positioning coordinates _G1 , _G2 , excavator mechanical component sizes and excavator working posture control parameters (ζ, φ, _θ1 , _θ2 , _θ3 ) calculated, The coordinates of the midpoint of the bottom edge of the excavator blade in the vehicle coordinate system are: x _in = x _d y_中＝y _d +L ₁ sinθ ₁ +L ₂ sin(θ ₁ +θ ₂ )+L ₃ sin(θ ₁ +θ ₂ +θ ₃ ) z_中＝z _d +L ₁ cosθ ₁ +L ₂ cos(θ ₁ +θ ₂ )+L ₃ cos(θ ₁ +θ ₂ +θ ₃ ) The coordinates of the left shovel tip of the excavator in the vehicle coordinate system are: _yleft ＝y _d +L ₁ sinθ ₁ +L ₂ sin(θ ₁ +θ ₂ )+L ₃ sin(θ ₁ +θ ₂ +θ ₃ ) _zleft ＝ _zd +L ₁ cosθ ₁ +L ₂ cos(θ ₁ +θ ₂ )+L ₃ cos(θ ₁ +θ ₂ +θ ₃ ) The coordinates of the left shovel tip of the excavator in the work area coordinate system are: K is the rotation matrix obtained by applying the Euler formula, where φ is the longitudinal tilt angle of the vehicle body, ζ is the lateral tilt angle of the vehicle body, obtained by the dual-axis tilt sensor, is the angle between the vehicle body and the north direction, which is calculated by _G1 and _G2 . Similarly, the coordinates of the right shovel tip of the excavator in the work area coordinate system can be calculated; (10) Real-time calculation of the minimum spatial distance S between the excavator tip and the underground pipe network BIM model. The specific method is as follows: The safety warning module of the vehicle terminal determines the pipeline segment to which the current working position of the excavator belongs based on the work area coordinates of the excavator's GNSS positioning, calls the BIM model of the underground pipeline network of the three segments closest to the current working position of the excavator, and calculates the pipeline distance. The spatial straight line equation determined by the start and end coordinates A (x ₁ , y ₁ , z ₁ ) and B (x ₂ , y ₂ , z ₂ ) of the central axis of the pipeline segment is: The vector (m,n,p) is the direction vector of line AB. The coordinates of the foot of the perpendicular D can be obtained by using the coordinates C (x _left , y _left , z _left ) of the left shovel tip of the excavator and the straight line AB. The equation of the straight line AB and the equation of the plane perpendicular to the straight line AB can be solved by combining m(xx _left )+n(yy _left )+p(zz _left )=0. The coordinates of D are (mk+x ₁ ,nk+y ₁ ,pk+z ₁ ), where: Then the distance from the left shovel tip coordinate C to the straight line AB is: If the foot of the perpendicular D is located on the line segment AB, the relative distance between the left shovel tip C of the excavator and the BIM model of the pipeline is: R＝CD-r If the foot of the perpendicular D is on the extension line of the line segment AB, then R is the minimum distance from the left shovel tip C of the excavator to the outer wall of the pipe end points A and B, and r is the radius of the pipe; The minimum spatial distance between the left shovel tip C of the excavator and the BIM model of all pipelines in the underground pipe network is: _Sleft ＝min R _i i＝1,2,3…M Where M is the number of pipelines contained in the current working area; Similarly, the minimum spatial distance _Sright , _Sleft and _Sright between the right shovel tip of the excavator and the BIM model of all pipelines in the three partitions can be obtained, which is the minimum spatial distance S between the shovel tip of the excavator and the BIM model of the underground pipe network. (11) Safety distance determination, multi-level safety warning and automatic braking. The specific methods are as follows: The safety warning module of the vehicle terminal compares the real-time calculated relative distance S between the excavator shovel tip and the underground pipe network BIM model with the set multi-level safety warning distances S _low and S _high . When S>S _low , it indicates that the excavator shovel tip is in the safe zone; when S _high <S <S _low , it indicates that the excavator shovel tip has entered the low-risk warning zone, and the operator is reminded by voice to be careful during construction; when S <S _high , it indicates that the excavator shovel tip has entered the high-risk warning zone, and the excavator bucket will automatically stop to avoid collision between the excavator shovel tip and the pipeline due to the operator's failure to stop the car in time; (12) Visual display of vehicle terminal; (13) The database and application server receive the data sent back by the vehicle terminal, analyze and store it; (14) Monitor client visual display, remote real-time monitoring and query statistics. 2. According to the method of intelligent guidance and safety warning of road excavation operation coupled with the BIM model of underground pipe network as described in claim 1, it is characterized by: in step (1), the developed monitoring client is logged in and the user authority is verified, the user authority includes browsing, operation and management, the browsing user can realize the functions of visual remote real-time monitoring, query and receiving alarm information; the operating user can create excavation tasks on the basis of having the browsing user authority, including inputting the excavator ID, setting multi-level safety warning areas, uploading the underground pipe network and excavator BIM model of the site and issuing the excavator dispatch instruction function; the management user, in addition to having the authority of the above two types of users, is responsible for managing the authority of other users. 3. According to the method of intelligent guidance and safety warning of road excavation operation coupled with the BIM model of underground pipe network as described in claim 1, it is characterized in that: the establishment and uploading of the BIM model of the underground pipe network and the excavator in the site in step (2) includes: obtaining the location information of the underground pipe network in the site through a pipeline avoidance instrument or a ground penetrating radar, and correcting the underground pipe network location data in combination with the CAD drawings of the underground pipe network construction organization design to obtain accurate underground pipe network location information; dividing the site into different sections according to a certain pipeline length, and cutting the pipes across the sections and the pipe turns, and expressing the pipes as cylinders determined by the starting coordinates of the central axis and the pipe diameter; numbering the pipes and binding them to the sections to which they belong, the starting coordinates of the central axis of the pipes and the pipe radius, thereby establishing the BIM model of the underground pipe network; measuring the size parameters of each mechanical component of the on-site construction excavator to establish the excavator BIM model. 4. According to claim 1, a method for intelligent guidance and safety warning of road excavation operations coupled with an underground pipe network BIM model is characterized in that: step (3) creates an excavation task on the monitoring client, including: setting the start and end segments and start and end times of the task and inputting the excavator ID corresponding to the current task; at the same time, according to the distance between the shovel tip and the pipeline, setting multiple levels of safety warning zones, which are respectively a safety zone, a low-risk warning zone and a high-risk warning zone from far to near. 5. According to claim 1, a method for intelligent guidance and safety warning of road excavation operations coupled with an underground pipe network BIM model is characterized in that: in step (4), the operating user issues an excavator dispatch instruction on the monitoring client, reminds the on-site construction management personnel to receive the excavator dispatch information in the form of text messages, and arranges the excavator operator to perform excavation operations; at the same time, the database and application server only receive data returned by the vehicle-mounted end within the excavator dispatch time period, and the operating user can issue an end dispatch instruction to terminate the on-site excavation operation based on the completion status of the excavation task. 6. According to the method of intelligent guidance and safety warning of road excavation operation coupled with the BIM model of underground pipe network in claim 1, it is characterized in that: the database and application server receive the excavation task information created by the monitoring client, the uploaded BIM model of the excavator and the underground pipe network in the site, and the issued excavator dispatch instruction, and store the above information in the database module of the database and application server; after receiving the excavator dispatch instruction, the on-site manager arranges the excavator operator to perform the excavation operation, the excavator operator turns on the vehicle-mounted terminal in the cab, and the vehicle-mounted terminal receives the corresponding excavation task information from the database and application server, and Automatically check whether the excavator model and underground pipe network model have changed. If there is a change, the on-board terminal automatically downloads and updates the corresponding BIM model. If there is no change, the excavation operation is carried out according to the BIM model used in the last excavation. Establish a differential base station at the construction site, install a GNSS positioning antenna on the excavator, and use GNSS-RTK positioning technology to collect the excavator coordinate information in real time. The main positioning antenna is used to determine the three-dimensional spatial coordinate position of the excavator. The auxiliary positioning antenna cooperates with the main positioning antenna to determine the direction angle of the excavator. The collected excavator positioning information is transmitted to the on-board terminal in real time for subsequent calculation and processing. 7. The method for intelligent guidance and safety warning of road excavation operation coupled with the BIM model of underground pipe network according to claim 1 is characterized in that: the intelligent guidance module of the vehicle-mounted terminal in step (12) visualizes the on-site excavation operation to guide the excavator operator to construct safely, It includes three-dimensional visualization of BIM models and real-time display of data. The on-board terminal determines the current working position according to the GNSS positioning information of the excavator, and automatically retrieves the BIM model of the underground pipeline network within a certain range of the excavator. According to the inclination data of the excavator's mechanical components collected by the inclination sensor, the three-dimensional dynamic display of each mechanical component of the excavator's BIM model is realized. The shovel tip can be partially enlarged and displayed, and the shovel tip can be connected to the nearest underground pipeline with a red line in real time to enhance the visualization effect of the excavation operation. 8. According to the method of intelligent guidance and safety warning of road excavation operation coupled with the BIM model of underground pipe network as described in claim 1, it is characterized in that: the data sent back by the vehicle terminal received by the database and application server in step (13) include: GNSS positioning data, inclination sensor data, shovel tip coordinate data, shovel tip coordinate relative distance data and underground pipe network and on-site alarm data; the analysis and calculation module of the database and application server uses the GNSS positioning data to draw the working position trajectory of the excavator in real time in three dimensions; uses the inclination sensor data to display the excavator BIM model in three dimensions on the monitoring client in real time; uses the shovel tip coordinate data to draw the shovel tip trajectory of the excavator in real time in three dimensions, and generates a thermal cloud map of the excavation operation to reflect the on-site construction situation; uses the shovel tip coordinate relative distance data and the underground pipe network to monitor the relative distance of the on-site excavation operation in real time; uses the on-site alarm data to display the safety warning situation on the monitoring client, including the alarm time, the number and position of the dangerous underground pipeline at the time of the alarm, the shovel tip coordinate at the time of the alarm and the alarm picture information. 9. According to the method of intelligent guidance and safety warning of road excavation operations coupled with the BIM model of underground pipe network as described in claim 1, it is characterized in that: the data displayed in step (14) includes excavator working position data, shovel tip coordinate data and relative distance data; the excavator working position trajectory, the excavator shovel tip trajectory and the excavation operation thermal cloud map can be drawn in real time in three dimensions, so as to realize remote real-time monitoring of the excavation operation construction site; at the same time, the monitoring client can query and count the on-site excavation operation results from the database and the database module of the application server, play back and browse the trajectory and graphics and output them in the form of video or chart, so as to facilitate the subsequent safety assessment of the entire excavation construction process.