A GNSS-based intelligent early warning control system, method, and storage medium for construction machinery operating near railway lines.

Abstract

This application provides a GNSS-based intelligent early warning control system, method, and storage medium for construction machinery operating near a railway line, relating to the field of obstacle avoidance technology for construction machinery. The method includes: acquiring three-dimensional coordinate information of the construction machinery body and dynamic end-effector's working point using at least one main GNSS positioning module and at least one secondary GNSS positioning module, respectively; combining this with pose sensing information collected by a pose sensor and preset machinery size parameters; accurately determining the three-dimensional spatial outer contour boundary of the construction machinery; and achieving comprehensive perception of the overall spatial position of the construction machinery. By determining the first minimum spatial distance between the three-dimensional spatial outer contour boundary and the warning fence, and the second minimum spatial distance with the parking fence, hierarchical early warning control is achieved. When preset locking conditions are met, a control level is automatically output, and the connection between the pilot solenoid valve circuit and the pilot oil circuit and the hydraulic system is cut off through the active parking control circuit, forcing the construction machinery into a locked-down state.

Description

Technical Field

[0001] This application relates to the field of obstacle avoidance technology for construction machinery, and in particular to a GNSS-based intelligent early warning control system, method and storage medium for construction machinery operating near railway lines. Background Technology

[0002] As infrastructure construction continues to expand, there are increasingly more construction projects being carried out near operational railway lines, highways, and other normally running lines. When construction is being carried out near operational lines, if the working parts of the construction machinery (such as booms and buckets) encroach on the safety clearance of the operational lines, they may collide with high-speed trains or vehicles, causing safety accidents.

[0003] In related technologies, to ensure the safety of construction work near operational railway lines, a combination of manual monitoring and simple alarms is typically used. Specifically, a warning line is set up, and on-site safety personnel manually observe the distance between construction machinery and the railway line, issuing warnings to the driver via walkie-talkie or hand gestures. Physical barriers are installed at the construction site to mark the safe working area. Proximity alarms are installed, using infrared beams or ultrasonic ranging to trigger audible and visual alarms when construction machinery approaches the railway line. This combination of manual monitoring and simple alarms effectively monitors the construction site and plays a positive role in ensuring construction safety.

[0004] However, the combination of manual monitoring and simple alarms has limitations in accuracy due to the limited distance precision of manual observation. It is difficult to accurately identify the safe distance between construction machinery and adjacent operating lines. Furthermore, the simple alarms are not effectively linked with the construction machinery, which can easily lead to missed alarms or untimely warnings. As a result, it is difficult to control the construction machinery to stop at the same time as the warning to avoid accidents. Consequently, the safety of construction machinery operating near operating lines in related technologies is poor. Summary of the Invention

[0005] This application provides a GNSS-based intelligent early warning control system, method, and storage medium for construction machinery operating near commercial railway lines, which can improve the safety of construction machinery operating near commercial railway lines.

[0006] In a first aspect, this application provides a GNSS-based intelligent early warning control system for construction machinery operating near a railway line, comprising: a control terminal, and at least one main GNSS positioning module, at least one slave GNSS positioning module, a pose sensor, and an active parking control loop, all communicatively connected to the control terminal; wherein, at least one main GNSS positioning module is installed on the construction machinery body for real-time acquisition of the vehicle's first three-dimensional coordinate information; at least one slave GNSS positioning module is installed at the dynamic end-point of the construction machinery for real-time acquisition of the dynamic end-point's second three-dimensional coordinate information; the pose sensor is used to collect the construction machinery's pose sensing information; the control terminal is used to collect the first three-dimensional coordinate information, the second three-dimensional coordinate information, the pose sensing information, and the active parking control loop. The system uses preset mechanical dimension parameters of the construction machinery to determine the three-dimensional spatial outer contour boundary of the construction machinery. It also uses the three-dimensional position information of the warning fence and parking fence to determine the first minimum spatial distance from the three-dimensional spatial outer contour boundary to the warning fence, and the second minimum spatial distance from the three-dimensional spatial outer contour boundary to the parking fence. The control terminal is also used to perform graded early warning control of the construction machinery based on the first and second minimum spatial distances, and outputs a control level to the active parking control circuit when the preset locking conditions are met. The active parking control circuit receives the control level and uses it to disconnect the pilot solenoid valve circuit and pilot oil circuit from the hydraulic system on the construction machinery, causing the construction machinery in dynamic operation to enter a locked state until an unlocking signal is received.

[0007] By adopting the above technical solution, at least one main GNSS positioning module and at least one secondary GNSS positioning module are used to acquire the three-dimensional coordinate information of the construction machinery body and the dynamic end-point operation point. Combined with the posture sensing information collected by the posture sensor and the preset mechanical size parameters, the three-dimensional spatial outer contour boundary of the construction machinery can be accurately determined, achieving comprehensive perception of the overall spatial position of the construction machinery. By determining the first minimum spatial distance between the three-dimensional spatial outer contour boundary and the warning fence, and the second minimum spatial distance between the boundary and the parking fence, hierarchical early warning control is achieved. When the preset locking conditions are met, the control level is automatically output, and the connection between the pilot solenoid valve circuit and the pilot oil circuit and the hydraulic system is cut off through the active parking control circuit, forcing the construction machinery into a locked state. This solves the technical problem of poor safety when construction machinery operates near operating lines in related technologies, achieving the technical effect of improving the safety of construction machinery operating near operating lines.

[0008] Optionally, the system further includes: an RTK handheld positioning terminal connected to the control terminal; the RTK handheld positioning terminal is used to collect point data at the construction site before construction, determine the coordinates of adjacent operating line edge feature points based on the point data, and send the coordinates of adjacent operating line edge feature points to the control terminal; the control terminal is also used to receive the coordinates of adjacent operating line edge feature points, perform trajectory fitting on the coordinates of adjacent operating line edge feature points, and generate an operating line baseline; the control terminal is also used to receive a first preset safety distance and a second preset safety distance input by the user through a human-machine interface, and generate three-dimensional position information with a parallel positional relationship to the operating line baseline based on the operating line baseline, the first preset safety distance, and the second preset safety distance; the control terminal is also used to store the three-dimensional position information.

[0009] By adopting the above technical solution, RTK handheld positioning terminals are used to collect point data at the construction site before construction to determine the coordinates of feature points near the edge of the operating line. The control terminal then performs trajectory fitting on these feature point coordinates to generate the operating line baseline. Based on the first and second preset safety distances input by the user, the three-dimensional position information of warning fences and parking fences that are parallel to the operating line baseline is automatically generated. This enables flexible setting and precise positioning of electronic fences. Users can independently set safety distances according to the actual construction site conditions, and the three-dimensional warning fences and parking fences are automatically generated. Compared with traditional physical fences or simple planar electronic fences, this solution can adapt to complex terrain and different construction needs, thereby improving the applicability and flexibility of the intelligent early warning control system.

[0010] Optionally, the above system also includes: an alarm device that is communicatively connected to the control terminal; the control terminal performs graded early warning control on the construction machinery in the following ways: when the first minimum spatial distance is less than or equal to the first preset distance threshold, the control terminal performs secondary early warning control to control the alarm device to output a target alarm signal and display risk warning information on the visual interface of the control terminal; when the second minimum spatial distance is less than or equal to the second preset distance threshold, the control terminal performs tertiary early warning control to output a control level to the active parking control loop.

[0011] By adopting the above technical solution, when the first minimum spatial distance is less than or equal to the first preset distance threshold, the control terminal performs a second-level early warning control, controlling the alarm device to output a target alarm signal (such as an audible and visual alarm) and displaying risk warning information on the visual interface to remind the driver to pay attention to the safe distance; when the second minimum spatial distance is less than or equal to the second preset distance threshold, the control terminal performs a third-level early warning control, outputting a control level to the active parking control loop to trigger a forced stop. This hierarchical early warning control method can form a complete risk control closed loop from prompting to alarming to forced stop, giving the driver the opportunity to make proactive adjustments and ensuring safety when the danger escalates. Even in extreme cases where the driver fails to respond in time, the forced stop through the three-level early warning can prevent accidents from occurring, effectively improving the safety of construction work on adjacent operating lines.

[0012] Optionally, the pose sensor includes an angle sensor and a height sensor; the angle sensor is installed on the construction machinery to detect the boom rotation angle of the construction machinery; the height sensor is installed on the construction machinery to detect the boom lifting height of the construction machinery; the control terminal performs graded early warning control on the construction machinery in the following ways: the control terminal is also used to receive the maximum boom rotation angle threshold and the maximum lifting height threshold set by the user through the human-machine interface, and when the boom rotation angle exceeds the maximum rotation angle threshold or the boom lifting height exceeds the maximum lifting height threshold, it performs three-level early warning control to output control level to the active stop control loop.

[0013] By adopting the above technical solution, the posture sensor includes an angle sensor and a height sensor, which are used to detect the boom rotation angle and boom lifting height of the construction machinery, respectively. The control terminal receives the user-set maximum boom rotation angle threshold and maximum lifting height threshold. When the boom rotation angle exceeds the maximum rotation angle threshold or the boom lifting height exceeds the maximum lifting height threshold, a three-level early warning control is implemented and a control level is output. This enables real-time monitoring and limit control of the boom posture of the construction machinery, providing effective three-dimensional protection for three-dimensional spatial operations such as boom rotation and lifting. It solves the problem that traditional protective measures are limited in function and cannot cope with three-dimensional spatial operations. Users can flexibly set the boom limit parameters according to the site conditions (such as the presence of another power line nearby or a contact wire above), perfectly adapting to the protection needs of special operations such as lifting and excavation.

[0014] Optionally, the active stop control circuit includes a hydraulic control unit; the hydraulic control unit is used to reduce the output flow of the hydraulic system to zero according to the preset deceleration curve within a preset buffer time after receiving the control level, and disconnect the pilot solenoid valve circuit and pilot oil circuit from the hydraulic system, so that the construction machinery enters the lock-up state; the control terminal is also used to dynamically calculate the preset buffer time and preset deceleration curve according to the current operating speed and load status of the construction machinery, and send the preset buffer time and preset deceleration curve to the hydraulic control unit.

[0015] By adopting the above technical solution, the active stop control circuit includes a hydraulic control unit. Upon receiving a control signal, the hydraulic control unit does not immediately cut off the hydraulic system. Instead, it gradually reduces the output flow of the hydraulic system to zero according to a preset deceleration curve within a preset buffer time. Then, it disconnects the pilot solenoid valve circuit and the pilot oil circuit from the hydraulic system. The control terminal dynamically calculates the preset buffer time and preset deceleration curve based on the current operating speed and load status of the construction machinery and sends these parameters to the hydraulic control unit, enabling it to execute the optimal deceleration process according to the actual working conditions. This gradual stop method avoids secondary dangers such as hydraulic system shock, sudden structural stress changes, boom inertial swing, and load fall that may occur with sudden stops, as well as potential injuries to the driver due to inertia. It protects the machinery while ensuring safety, thus achieving a smooth and safe forced stop process.

[0016] Optionally, the system further includes: a manual unlocking device connected to the active parking control circuit; the manual unlocking device is used to receive the user's manual unlocking operation after the construction machinery enters the locked-down state, and send a temporary unlocking signal to the active parking control circuit; the active parking control circuit is used to restore the connection between the pilot solenoid valve circuit and the pilot oil circuit and the hydraulic system after receiving the temporary unlocking signal, and temporarily release the locked-down state; the control terminal is also used to monitor the position change of the construction machinery in real time after the locked-down state is temporarily released, and when the second minimum spatial distance is detected to be greater than the third preset distance threshold, send a confirmation unlocking signal to the active parking control circuit, or when the second minimum spatial distance is detected to be less than the third preset distance threshold, re-output the control level to the active parking control circuit; the active parking control circuit is used to completely release the locked-down state after receiving the confirmation unlocking signal, or to put the construction machinery into the locked-down state after receiving the re-output control level.

[0017] By adopting the above technical solution, the intelligent early warning control system is equipped with a manual unlocking device, allowing the driver or site manager to temporarily release the lock after the construction machinery has been locked, enabling the machinery to move in a safe direction. After the lock is temporarily released, the control terminal continuously monitors the position changes of the construction machinery. When the machinery moves to a safe area (the second minimum spatial distance is greater than the third preset distance threshold), the system automatically sends a confirmation unlocking signal, completely releasing the lock and allowing the machinery to resume normal operation. If the machinery fails to move to a safe area, the system re-triggers the lock to ensure safety. This mechanism, combining manual unlocking and automatic monitoring, not only solves the physical paradox of the machinery being unable to move on its own after being locked, but also ensures, through continuous monitoring and conditional judgment, that the lock is only completely released after the machinery has truly returned to a safe area, thus avoiding safety hazards and achieving a balance between safety and operability.

[0018] Secondly, this application provides a GNSS-based intelligent early warning control method for construction machinery operating near a business line, applied in any of the aforementioned intelligent early warning control systems. The method includes: real-time acquisition of first three-dimensional coordinate information of the construction machinery body collected by at least one main GNSS positioning module; real-time acquisition of second three-dimensional coordinate information of at least one dynamic end-point work point of the construction machinery collected by the GNSS positioning module; acquisition of pose sensing information of the construction machinery collected by a pose sensor; determination of the three-dimensional spatial outer contour boundary of the construction machinery based on the first three-dimensional coordinate information, the second three-dimensional coordinate information, the pose sensing information, and preset mechanical size parameters of the construction machinery; determination of a first minimum spatial distance from the three-dimensional spatial outer contour boundary to the warning fence and a second minimum spatial distance from the three-dimensional spatial outer contour boundary to the parking fence based on the three-dimensional position information of the warning fence and the parking fence; hierarchical early warning control of the construction machinery based on the first and second minimum spatial distances; and outputting a control level to the active parking control circuit when preset locking conditions are met; upon receiving the control level, disconnecting the pilot solenoid valve circuit and pilot oil circuit on the construction machinery from the hydraulic system via the active parking control circuit, causing the construction machinery in dynamic operation to enter a locked state until an unlocking signal is received.

[0019] Optionally, the three-dimensional position information stored in the control terminal is generated by performing the following steps: when the coordinates of the feature points on the edge of the adjacent business line collected by the RTK handheld positioning terminal are obtained, the coordinates of the feature points on the edge of the adjacent business line are fitted to generate the business line baseline; the first preset safety distance and the second preset safety distance are received by the user through the human-machine interface, and three-dimensional position information with a parallel positional relationship to the business line baseline is generated according to the business line baseline, the first preset safety distance and the second preset safety distance.

[0020] Optionally, the construction machinery can be subjected to graded early warning control based on a first minimum spatial distance and a second minimum spatial distance, including: when the first minimum spatial distance is less than or equal to a first preset distance threshold, a second-level early warning control is performed to control the alarm device to output a target alarm signal and display risk warning information on the visual interface of the control terminal; when the second minimum spatial distance is less than or equal to a second preset distance threshold, a third-level early warning control is performed to control the terminal to output a control level to the active parking control loop.

[0021] Thirdly, embodiments of this application provide a computer program product containing instructions that, when the computer program product is run on an intelligent early warning control system, cause the intelligent early warning control system to execute the method described in the first aspect and any possible implementation thereof.

[0022] Fourthly, embodiments of this application provide a computer-readable storage medium including instructions that, when executed on an intelligent early warning control system, cause the intelligent early warning control system to perform the method described in the first aspect and any possible implementation thereof. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the architecture of a GNSS-based intelligent early warning control system for construction machinery near an operational railway line, provided in an embodiment of this application.

[0024] Figure 2 This is a schematic diagram illustrating the working principle of the warning line and the parking line in a GNSS-based intelligent early warning control system for construction machinery near an operational railway line, as provided in this application embodiment.

[0025] Figure 3 This is a flowchart of a GNSS-based intelligent early warning control method for construction machinery operating near a commercial railway line, as described in an embodiment of this application. Detailed Implementation

[0026] The terminology used in the following embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. As used in the specification and appended claims of this application, the singular expressions “a,” “an,” “the,” “the,” “the,” and “this” are intended to include the plural expressions as well, unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used in this application refers to any or all possible combinations including one or more of the listed items.

[0027] Hereinafter, the terms "first" and "second" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature, and in the description of the embodiments of this application, unless otherwise stated, "multiple" means two or more.

[0028] The following is in conjunction with the appendix Figure 1 - Appendix Figure 3 The embodiments of this application will be described in detail.

[0029] This application provides a GNSS-based intelligent early warning and control system for construction machinery operating near railway lines. (See attached document.) Figure 1 , Figure 1 This application provides a schematic diagram of the architecture of a GNSS-based intelligent early warning control system for construction machinery operating near a railway line. The system includes: a control terminal, and at least one main GNSS positioning module, at least one slave GNSS positioning module, a pose sensor, and an active stop control loop, all communicatively connected to the control terminal. At least one main GNSS positioning module is installed on the construction machinery body to acquire the first three-dimensional coordinate information of the body in real time. At least one slave GNSS positioning module is installed at the dynamic end-point of the construction machinery to acquire the second three-dimensional coordinate information of the dynamic end-point in real time. The pose sensor is used to collect the pose sensing information of the construction machinery. The control terminal uses the first three-dimensional coordinate information, the second three-dimensional coordinate information, and the pose sensing information to... The system uses information and preset mechanical size parameters of the construction machinery to determine the three-dimensional spatial outer contour boundary of the construction machinery. It also uses the three-dimensional position information of the warning fence and parking fence to determine the first minimum spatial distance from the three-dimensional spatial outer contour boundary to the warning fence, and the second minimum spatial distance from the three-dimensional spatial outer contour boundary to the parking fence. The control terminal is also used to perform graded early warning control of the construction machinery based on the first and second minimum spatial distances, and outputs a control level to the active parking control circuit when the preset locking conditions are met. The active parking control circuit receives the control level and uses it to disconnect the pilot solenoid valve circuit and pilot oil circuit from the hydraulic system on the construction machinery, causing the construction machinery in dynamic operation to enter a locked state until an unlocking signal is received.

[0030] The control terminal, the core control unit of the intelligent early warning control system, is installed in the cab of the construction machinery. It has a built-in high-performance processor and memory, and runs the core algorithm. The control terminal has data receiving and processing functions, distance calculation functions, visualization display functions, early warning control functions, and human-machine interaction functions. The main GNSS positioning module is installed on the construction machinery body (e.g., on the top of the cab) and uses RTK (Real-Time Kinematic) differential positioning technology to acquire the three-dimensional spatial coordinate information of the construction machinery body in real time, with positioning accuracy down to the centimeter level. The main GNSS positioning module is installed using a modular quick-release structure such as a strong magnetic chuck or quick-release clips, facilitating rapid deployment and relocation. Secondary GNSS positioning modules are installed at the dynamic end-points of the construction machinery (e.g., the end of the boom, the bucket, etc.), also using RTK differential positioning technology to acquire the three-dimensional spatial coordinate information of the dynamic end-points in real time, with positioning accuracy down to the centimeter level. There can be one or more secondary GNSS positioning modules, installed at different key operating points according to the operating characteristics of the construction machinery. Attitude sensors are used to collect the attitude sensing information of the construction machinery, including angle sensors and height sensors. An angle sensor detects the rotation angle of the construction machinery's boom, and a height sensor detects the boom's lifting height. A pose sensor is installed on the construction machinery body and communicates with the control terminal. The three-dimensional spatial outer contour boundary refers to the overall outer contour boundary of the construction machinery in three-dimensional space, determined through spatial geometric calculations based on the vehicle's three-dimensional coordinate information obtained from the main GNSS positioning module, the dynamic end-point work point's three-dimensional coordinate information obtained from the GNSS positioning module, the pose sensing information collected by the pose sensor, and the construction machinery's preset mechanical size parameters (such as vehicle length, width, height, boom length, etc.). This three-dimensional spatial outer contour boundary can completely describe the three-dimensional spatial range occupied by the construction machinery in its current posture.

[0031] The warning fence is a three-dimensional electronic fence parallel to the operating line baseline, generated based on the operating line baseline and a first preset safety distance (e.g., 20 meters from the operating line). As the first line of defense, the warning fence triggers a secondary warning control when the outer boundary of the construction machinery approaches or touches it. The parking fence is a three-dimensional electronic fence parallel to the operating line baseline, generated based on the operating line baseline and a second preset safety distance (e.g., 10 meters from the operating line). As the final line of defense, the parking fence triggers a tertiary warning control, forcibly locking the construction machinery when its outer boundary touches or intrudes upon it. The first minimum spatial distance refers to the minimum distance from any point on the outer boundary of the construction machinery to the warning fence, reflecting the closest distance between the construction machinery and the warning fence. The second minimum spatial distance refers to the minimum distance from any point on the outer boundary of the construction machinery to the parking fence, reflecting the closest distance between the construction machinery and the parking fence. The preset locking conditions include distance-based locking conditions and attitude-based locking conditions. The distance-based locking condition is that the second minimum spatial distance is less than or equal to the second preset distance threshold. The attitude-based locking condition is that the boom slewing angle exceeds the maximum slewing angle threshold or the boom lifting height exceeds the maximum lifting height threshold. When any locking condition is met, the control terminal outputs a control level to the active stop control loop.

[0032] The active parking control circuit includes components such as a hydraulic control unit, relays, and wiring harnesses. Power is drawn from the construction machinery's cigarette lighter, connected to the control terminal in the cab via an integrated wiring harness, and then routed from the cab to the pilot solenoid valve circuit of the construction machinery. A matching adapter with a relay is used in the pilot solenoid valve circuit to control its on / off state. When a control level (high-level signal) is received from the control terminal, the relay coil is energized. The hydraulic control unit reduces the hydraulic system's output flow to zero according to a preset deceleration curve within a preset buffer time. Then, the connection between the pilot solenoid valve circuit and the pilot oil circuit and the hydraulic system is severed, putting the construction machinery into a locked-down state. The locked-down state means that the construction machinery's travel and motion systems (such as the boom and bucket) are locked, preventing further movement or operation in dangerous directions. In the locked-down state, the driver's commands are not executed, and the construction machinery remains stationary until an unlock signal is received. The unlock signal is sent by the control terminal to the active parking control circuit when it detects that the construction machinery is moving in a safe direction away from the parking barrier, and the second minimum spatial distance is greater than a third preset distance threshold. After receiving the unlock signal, the active stop control circuit restores the connection between the pilot solenoid valve circuit and the pilot oil circuit and the hydraulic system, releases the lock-up state, and the construction machinery resumes normal operation.

[0033] In the above embodiments, at least one primary GNSS positioning module is mounted on the construction machinery body (such as the top of the excavator cab) via a strong magnetic chuck, ensuring unobstructed antenna reception of satellite signals. At least one secondary GNSS positioning module is mounted at the dynamic end-effector of the construction machinery (such as the end of the excavator boom or the bucket position). Angle and height sensors from the pose sensors are mounted on the construction machinery body to detect the boom's rotation angle and lifting height. All positioning modules and sensors are wirelessly or wiredly connected to a control terminal installed in the cab. The primary and secondary GNSS positioning modules employ RTK differential positioning technology to acquire real-time three-dimensional spatial coordinate information of the construction machinery body and the dynamic end-effector, achieving centimeter-level positioning accuracy. The pose sensors collect real-time information on the boom's rotation angle and lifting height. The control terminal receives and processes data from all positioning modules and sensors. The control terminal determines the three-dimensional spatial outer contour boundary of the construction machinery through spatial geometric calculations based on the received first three-dimensional coordinate information (vehicle coordinates), second three-dimensional coordinate information (dynamic end-effector coordinates), pose sensing information (boom rotation angle and lifting height), and pre-stored preset mechanical dimension parameters of the construction machinery (such as vehicle length, width, height, boom length, etc.). This three-dimensional spatial outer contour boundary completely describes the three-dimensional space occupied by the construction machinery in its current posture, including the spatial positions of all components such as the vehicle body, boom, and bucket.

[0034] In the above embodiment, the control terminal reads the pre-set three-dimensional position information of the warning fence and parking fence from the memory, calculates all distances from any point on the three-dimensional spatial outer contour boundary of the construction machinery to the warning fence, and takes the minimum value as the first minimum spatial distance; similarly, it calculates all distances from any point on the three-dimensional spatial outer contour boundary to the parking fence, and takes the minimum value as the second minimum spatial distance. The control terminal performs the above calculations at a high speed of 20 times per second to achieve real-time distance monitoring. The control terminal performs graded early warning control on the construction machinery based on the first and second minimum spatial distances. When the first minimum spatial distance is less than a fourth preset distance threshold (e.g., 3 meters), the control terminal performs first-level early warning control, outputs intermittent alert sounds on the visual display screen, and changes the display color of the first minimum spatial distance to yellow to remind the driver to pay attention to the safe distance. When the first minimum spatial distance is less than or equal to the first preset distance threshold (such as the boundary of a warning fence), the control terminal performs secondary warning control, controls the alarm device to output a target alarm signal (high-decibel audible alarm and high-brightness flashing warning), and displays risk warning information on the visual interface (such as "Danger! You have crossed the boundary, please retreat immediately!"), and the distance number on the screen turns red. When the second minimum spatial distance is less than or equal to the second preset distance threshold (such as the boundary of a parking fence), or when the boom slewing angle exceeds the maximum slewing angle threshold or the boom lifting height exceeds the maximum lifting height threshold, the control terminal determines that the preset locking conditions are met, performs tertiary warning control, and outputs a control level (high-level signal) to the active parking control loop.

[0035] In the above embodiment, after receiving the control level, the relay coil of the active stop control circuit is energized, and the hydraulic control unit is activated. The hydraulic control unit dynamically calculates the preset buffer time and preset deceleration curve based on the current operating speed and load status of the construction machinery. Within the preset buffer time (e.g., 2-5 seconds), the hydraulic control unit gradually reduces the output flow of the hydraulic system according to the preset deceleration curve, allowing the construction machinery to decelerate smoothly. When the output flow of the hydraulic system drops to zero, the active stop control circuit disconnects the pilot solenoid valve circuit and pilot oil circuit from the hydraulic system, causing the construction machinery to enter a locked-down state. At this time, the walking and motion systems of the construction machinery are locked, the driver's operating commands are not executed, and the construction machinery remains stationary. The control terminal displays the message "Emergency lock triggered, please operate in a safe direction to unlock" on the visual interface. After the construction machinery enters the locked-down state, the control terminal continuously monitors the position changes of the construction machinery in real time. When the control terminal detects that the construction machinery is moving in a safe direction away from the parking barrier (e.g., the driver manually tows the machinery backward), and the second minimum spatial distance is greater than the third preset distance threshold (e.g., 15 meters), the control terminal determines that the construction machinery has returned to the safe area and sends an unlock signal to the active parking control circuit. After receiving the unlock signal, the active parking control circuit de-energizes the relay coil, restores the connection between the pilot solenoid valve circuit and the pilot oil circuit and the hydraulic system, releases the lock-up state, and the construction machinery resumes normal operation.

[0036] Through the above steps, by utilizing at least one primary GNSS positioning module and at least one secondary GNSS positioning module to acquire the three-dimensional coordinate information of the construction machinery body and the dynamic end-effector, and combining this with the pose sensing information collected by the pose sensor and preset mechanical size parameters, the three-dimensional spatial outer contour boundary of the construction machinery can be accurately determined, achieving comprehensive perception of the overall spatial position of the construction machinery. By determining the first minimum spatial distance between the three-dimensional spatial outer contour boundary and the warning fence, and the second minimum spatial distance between the boundary and the parking fence, hierarchical early warning control is achieved. When the preset locking conditions are met, a control level is automatically output, and the connection between the pilot solenoid valve circuit and the pilot oil circuit and the hydraulic system is cut off through the active parking control circuit, forcing the construction machinery into a locked-down state. This solves the technical problem of poor safety when construction machinery operates near an operational line in related technologies, achieving the technical effect of improving the safety of construction machinery operating near an operational line.

[0037] In an optional embodiment, the system further includes: an RTK handheld positioning terminal communicatively connected to a control terminal; the RTK handheld positioning terminal is used to collect point data at the construction site before construction, determine the coordinates of adjacent operating line edge feature points based on the point data, and send the coordinates of adjacent operating line edge feature points to the control terminal; the control terminal is also used to receive the coordinates of adjacent operating line edge feature points, perform trajectory fitting on the coordinates of adjacent operating line edge feature points, and generate an operating line baseline; the control terminal is also used to receive a first preset safety distance and a second preset safety distance input by the user through a human-machine interface, and generate three-dimensional position information with a parallel positional relationship to the operating line baseline based on the operating line baseline, the first preset safety distance, and the second preset safety distance; the control terminal is also used to store the three-dimensional position information.

[0038] The RTK handheld positioning terminal is a portable, high-precision GNSS positioning device that uses RTK (Real-Time Kinematic) differential positioning technology, achieving centimeter-level positioning accuracy. It is used by site managers or surveyors before construction to collect point data at the construction site and determine the coordinates of feature points along the edge of adjacent railway lines. The RTK handheld positioning terminal has coordinate recording, data storage, and data transmission functions, capable of transmitting the collected coordinate data to the control terminal wirelessly or via wired connection. The coordinates of feature points along the edge of adjacent railway lines refer to the three-dimensional spatial coordinates of several key points collected along the edge of the railway line (such as the edge of railway tracks or the edge of highway shoulders). These feature point coordinates describe the actual location and direction of the railway line and are the basic data for generating the railway line baseline. The railway line baseline is a continuous and smooth three-dimensional spatial curve generated by the control terminal based on the coordinates of the feature points along the edge of adjacent railway lines, using trajectory fitting algorithms (such as least squares method, spline interpolation, etc.). This curve accurately describes the centerline position and direction of the railway line. The railway line baseline serves as a reference for generating warning fences and parking fences. The first preset safety distance is the distance between the warning fence and the service line baseline, input by the user through the human-computer interaction interface, for example, 20 meters. This distance is determined based on the actual conditions of the construction site and safety regulations, and is used to generate the warning fence. The second preset safety distance is the distance between the parking fence and the service line baseline, input by the user through the human-computer interaction interface, for example, 10 meters. This distance is also determined based on the actual conditions of the construction site and safety regulations, and is used to generate the parking fence. The second preset safety distance is less than the first preset safety distance. Parallel positional relationship means that the warning fence and parking fence maintain an equidistant relationship with the service line baseline in three-dimensional space. That is, the distance from any point on the warning fence to the service line baseline is the first preset safety distance, and the distance from any point on the parking fence to the service line baseline is the second preset safety distance. This parallel positional relationship ensures that the warning fence and parking fence can completely cover the entire route of the service line, forming a continuous three-dimensional electronic fence.

[0039] In the above embodiment, during the initialization phase before construction, on-site management personnel or surveyors use RTK handheld positioning terminals to walk along the edge of the adjacent operating line (such as the edge of railway tracks), collecting data at regular intervals (e.g., 5-10 meters). The RTK handheld positioning terminal employs RTK differential positioning technology to acquire the three-dimensional spatial coordinates of the current location in real time, achieving centimeter-level positioning accuracy. During the data collection process, management personnel ensure that the collected points accurately reflect the actual location and direction of the operating line, especially increasing the density of collection points at key locations such as curves and slope changes. After data collection, the RTK handheld positioning terminal transmits the coordinates of all adjacent operating line edge feature points (such as three-dimensional coordinate data including east longitude, north latitude, and altitude) to the control terminal via a wireless network (such as Wi-Fi, 4G) or a wired connection (such as a USB data cable). Upon receiving the coordinates of the adjacent operating line edge feature points, the control terminal stores these coordinate data in its memory. The control terminal then performs trajectory fitting processing on the received coordinates of the adjacent operating line edge feature points. Specifically, the control terminal uses the least squares method or spline interpolation algorithm to fit a continuous and smooth three-dimensional spatial curve based on the coordinates of all feature points. This curve is the baseline of the operating line. The baseline accurately describes the centerline position and direction of the operating line, including its planar position and elevation changes.

[0040] In the above embodiments, the user (such as a construction site safety manager) inputs a first preset safety distance and a second preset safety distance through the human-machine interface of the control terminal. For example, according to railway safety regulations and actual site conditions, the user inputs a first preset safety distance of 20 meters and a second preset safety distance of 10 meters. After receiving these two safety distance parameters, the control terminal generates the three-dimensional position information of the warning fence and the parking fence through spatial geometric calculation based on the operating line baseline, the first preset safety distance, and the second preset safety distance. Specifically, based on the operating line baseline, the control terminal offsets the first preset safety distance (20 meters) towards the construction work area in a direction perpendicular to the operating line baseline, generating a three-dimensional spatial curve that is parallel to the operating line baseline. This curve is the warning fence. The distance from any point on the warning fence to the operating line baseline is 20 meters. Similarly, the control terminal offsets the second preset safety distance (10 meters) towards the construction work area in a direction perpendicular to the operating line baseline, generating the parking fence. The distance from any point on the parking fence to the operating line baseline is 10 meters. The generated 3D position information of the warning fence and parking fence includes the 3D spatial coordinates of each point on the fence. This coordinate data is stored in the memory of the control terminal for subsequent real-time distance calculations. The control terminal displays the positions of the operating line baseline, warning fence, and parking fence in a graphical manner on a visual display screen, forming an intuitive electronic map to help drivers understand the safe operating range.

[0041] In an optional embodiment, the system further includes: an alarm device communicatively connected to a control terminal; the control terminal performs graded early warning control on the construction machinery in the following manner: when the first minimum spatial distance is less than or equal to a first preset distance threshold, the control terminal performs secondary early warning control to control the alarm device to output a target alarm signal and display risk warning information on the visual interface of the control terminal; when the second minimum spatial distance is less than or equal to a second preset distance threshold, the control terminal performs tertiary early warning control to output a control level to the active parking control loop.

[0042] The alarm system includes an audible alarm and a flashing warning light. The audible alarm is a high-decibel sound, installed in the cab, capable of emitting a rapid voice alarm (e.g., "Danger! Boundary crossed, please retreat immediately!") and intermittent beeps (e.g., "beep beep"). The flashing warning light is a high-brightness flashing warning light, installed in a conspicuous location outside the cab, capable of flashing a warning light signal at high frequency. The alarm system communicates with the control terminal and receives control commands from the control terminal. The secondary warning control is the second level of the tiered warning control system. It is triggered when the three-dimensional spatial outer contour boundary of the construction machinery touches or crosses the warning fence, i.e., when the first minimum spatial distance is less than or equal to the first preset distance threshold. The specific actions of the secondary warning control include: the control terminal controlling the alarm system to output a target alarm signal (the audible alarm emits a rapid voice alarm, and the flashing warning light flashes at high frequency), and displaying risk warning information (e.g., "Danger! Boundary crossed, please retreat immediately!") on the control terminal's visual interface, while simultaneously changing the display color of the distance numbers to red. Level 2 warning control aims to raise the driver's alertness through strong audible and visual alarms, prompting the driver to immediately take measures to move the construction machinery away from the danger zone. Level 3 warning control is the highest level of tiered warning control. It is triggered when the three-dimensional spatial outer contour boundary of the construction machinery touches or intrudes into the parking barrier, i.e., the second minimum spatial distance is less than or equal to the second preset distance threshold, or when the boom slewing angle exceeds the maximum slewing angle threshold or the boom lifting height exceeds the maximum lifting height threshold. The specific actions of Level 3 warning control include: the control terminal continues to control the alarm device to output the target alarm signal and outputs a control level (high-level signal) to the active parking control circuit, triggering the active parking control circuit to execute a forced stop operation. Level 3 warning control is the last line of defense. By forcibly stopping the construction machinery, it ensures that even in the extreme case where the driver fails to respond to the Level 2 warning in time, the construction machinery is prevented from intruding into the operational safety clearance.

[0043] The first preset distance threshold is the distance threshold that triggers the secondary warning control. It is typically set at the boundary of the warning fence. When the first minimum spatial distance is less than or equal to this threshold, it indicates that the three-dimensional spatial outer contour boundary of the construction machinery has touched or crossed the warning fence. In practical applications, the first preset distance threshold can be set to 0 meters (indicating just touching the warning fence) or a small positive value (e.g., 0.5 meters, indicating that a warning is triggered when the machinery approaches the warning fence by 0.5 meters). The second preset distance threshold is the distance threshold that triggers the tertiary warning control. It is typically set at the boundary of the parking fence. When the second minimum spatial distance is less than or equal to this threshold, it indicates that the three-dimensional spatial outer contour boundary of the construction machinery has touched or intruded into the parking fence. In practical applications, the second preset distance threshold can be set to 0 meters (indicating just touching the parking fence) or a small positive value (e.g., 0.5 meters, indicating that a lock-up is triggered when the machinery approaches the parking fence by 0.5 meters). Target alarm signals include audible alarm signals and flashing warning signals. The audible alarm signal is a high-decibel, rapid voice alarm and intermittent prompt tone, while the flashing warning signal is a high-brightness, high-frequency flashing light signal. Target alarm signals are designed to attract the driver's attention through strong audio-visual stimuli, ensuring the driver can perceive dangerous situations in a timely manner. Risk warning information is text or graphic prompts displayed on the visual interface of the control terminal, used to inform the driver of the current dangerous situation and the measures to be taken. Examples include, "Danger! Boundary crossed, please back up immediately!", "Alarm, 20-meter warning, please back up", and "Alarm, 10-meter warning, please stop the machine". Risk warning information is usually displayed in a bright color (such as red) and a large font to ensure the driver can quickly read and understand it.

[0044] In the above embodiments, see Figure 2 , Figure 2 This application provides a schematic diagram illustrating the working principle of a GNSS-based intelligent early warning control system for construction machinery operating near a railway line, specifically a warning line and a parking line. It assumes the control terminal calculates the first minimum spatial distance from the three-dimensional spatial outer boundary of the construction machinery to the warning fence and the second minimum spatial distance to the parking fence in real time, 20 times per second, and displays these two distance values ​​digitally and graphically on a visual display screen. Level 1 Warning (Alert): When the first minimum spatial distance is less than a fourth preset distance threshold (e.g., 3 meters) but has not yet reached the warning fence, the control terminal initiates a Level 1 warning. Specifically, the control terminal outputs intermittent alert sounds (e.g., a "beep" sound, ringing every 2 seconds) on the visual display screen and changes the display color of the first minimum spatial distance from the normal green to a preset alert color (e.g., yellow). At this time, the visual interface displays "Distance from warning line: 2.35 meters" (yellow text), reminding the driver to maintain a safe distance without triggering the alarm device. The Level 1 warning is a mild alert, giving the driver sufficient time to proactively adjust the position or operating posture of the construction machinery.

[0045] In the above embodiment, the secondary warning (alarm) is as follows: When the construction machinery continues to move or operate towards the operating line, and the first minimum spatial distance is less than or equal to the first preset distance threshold (e.g., 0 meters, indicating that the three-dimensional spatial outer contour boundary just touches the warning fence), the control terminal determines that the construction machinery has crossed the warning fence and immediately initiates secondary warning control. Specifically, the control terminal sends a control command to the alarm device, controlling the alarm device to output a target alarm signal: the audible alarm in the cab emits a high-decibel urgent voice alarm "Danger! Crossed the boundary, please retreat immediately!", and the flashing warning lights outside the cab begin to flash at a high frequency (e.g., flashing 5 times per second), emitting a strong warning light signal. At the same time, the control terminal displays the risk warning information "Danger! Crossed the boundary, please retreat immediately!" on the visual interface and changes the display color of the first minimum spatial distance to red, with the distance number displayed prominently in red. The secondary warning, through a strong audible and visual alarm and a prominent interface prompt, arouses the driver's high alertness, prompting the driver to immediately stop moving or operating towards the operating line and drive the construction machinery away from the danger zone.

[0046] In the above embodiment, the three-level warning (lock-up) is as follows: If the driver fails to respond to the second-level warning in time and the construction machinery continues to move or operate in the direction of the operating line, and the second minimum spatial distance is less than or equal to the second preset distance threshold (e.g., 0 meters, indicating that the outer contour boundary of the three-dimensional space just touches the parking fence), the control terminal determines that the construction machinery has touched or intruded into the parking fence, meeting the preset locking conditions, and immediately performs the third-level warning control. Specifically, the control terminal continues to control the alarm device to output the target alarm signal (the audible alarm emits a voice alarm saying "Alarm, 10-meter warning, please stop!" and the flashing warning light flashes continuously at a high frequency), and outputs a control level (high-level signal) to the active parking control circuit. After receiving the control level, the active parking control circuit immediately starts the forced locking procedure, and through the hydraulic control unit, reduces the output flow of the hydraulic system to zero according to the preset deceleration curve within the preset buffer time, and then cuts off the connection between the pilot solenoid valve circuit and the pilot oil circuit and the hydraulic system, so that the construction machinery enters the locked-up state. At this time, the walking system and the action system of the construction machinery are locked, the driver's operation commands will not be executed, and the construction machinery remains stationary. The control terminal displays a message on the visual interface stating, "Emergency lock triggered, please move in a safe direction to unlock." Through the tiered control of Level 1, Level 2, and Level 3 warnings, a complete risk control loop is formed, progressing from mild alerts to strong alarms and finally to mandatory shutdown. Level 1 warnings give drivers an opportunity to proactively adjust; Level 2 warnings trigger strong audible and visual alarms to heighten driver alertness; and Level 3 warnings, in extreme cases where the driver fails to respond in time, forcibly shut down the construction machinery to ensure safe operation. This tiered warning control method respects the driver's right to proactive operation while also ensuring safety when necessary, significantly improving the safety of construction work near operational lines.

[0047] In an optional embodiment, the pose sensor includes an angle sensor and a height sensor; the angle sensor is installed on the construction machinery to detect the boom rotation angle of the construction machinery; the height sensor is installed on the construction machinery to detect the boom lifting height of the construction machinery; the control terminal performs graded early warning control on the construction machinery in the following manner: the control terminal is also used to receive the maximum boom rotation angle threshold and the maximum lifting height threshold set by the user through the human-machine interface, and when the boom rotation angle exceeds the maximum rotation angle threshold or the boom lifting height exceeds the maximum lifting height threshold, it performs three-level early warning control to output a control level to the active stop control loop.

[0048] Angle sensors, a component of the posture sensor system, are installed on the boom slewing mechanism of the construction machinery to detect the boom's slewing angle in real time. Angle sensors can be rotary encoders, gyroscopes, or tilt sensors, and can accurately measure the boom's slewing angle relative to the machinery's body, with a measurement accuracy of up to 0.1 degrees. The angle sensor transmits the detected boom slewing angle data to the control terminal via wired or wireless means. Height sensors, also a component of the posture sensor system, are installed on the boom lifting mechanism of the construction machinery to detect the boom's lifting height in real time. Height sensors can be cable displacement sensors, laser rangefinders, or ultrasonic sensors, and can accurately measure the lifting height of the boom's end relative to the ground or the machinery's body, with a measurement accuracy down to the centimeter level. The height sensor transmits the detected boom lifting height data to the control terminal via wired or wireless means.

[0049] The boom slewing angle refers to the slewing angle of the construction machinery's boom relative to the machinery's body in the horizontal plane. With the longitudinal centerline of the machinery's body as the 0-degree reference line, leftward slewing is a negative angle, and rightward slewing is a positive angle, typically ranging from -180 degrees to +180 degrees. The boom slewing angle reflects the boom's working range in the horizontal direction. The boom lifting height refers to the vertical height of the boom's end relative to the ground or the machinery's body. The boom lifting height reflects the boom's working range in the vertical direction; for construction machinery such as cranes and excavators, it is a crucial operating parameter. The maximum boom slewing angle threshold is the maximum allowable slewing angle limit set by the user through the human-machine interface. For example, if there is another utility line or other obstacle next to the construction site, the user can set the maximum boom slewing angle threshold to +60 degrees, meaning the boom cannot slew more than 60 degrees to the right. When the boom slewing angle exceeds this threshold, a three-level warning control is triggered. The maximum lifting height threshold is the maximum allowable lifting height limit of the boom set by the user through the human-machine interface. For example, if there is an overhead contact line or high-voltage line above the construction site, the user can set the maximum lifting height threshold to 8 meters, meaning that the lifting height of the boom end must not exceed 8 meters. When the boom lifting height exceeds this threshold, a three-level early warning control is triggered.

[0050] In the above embodiments, a boom attitude limit control function is provided for construction machinery with booms (such as excavators, cranes, rotary drilling rigs, etc.). During the system installation phase, an angle sensor is installed at the boom slewing mechanism of the construction machinery (such as at the slewing bearing or slewing reducer), and is fixed by mechanical connection or magnetic adsorption to ensure accurate sensing of the boom's slewing angle. A height sensor is installed at the boom lifting mechanism of the construction machinery (such as at the boom root or hydraulic cylinder), and measures the lifting height of the boom end by means of rope, laser, or ultrasonic methods. Both the angle sensor and the height sensor are connected to the control terminal via wiring harnesses to transmit detection data in real time. During the initialization phase before construction, the user (such as the construction site safety manager or driver) sets the maximum boom slewing angle threshold and the maximum lifting height threshold through the human-machine interface of the control terminal according to the actual conditions of the construction site. For example, if there is another power line 10 meters to the left of the construction site, to prevent the boom from encroaching on the safety clearance of that power line during slewing, the user sets the maximum slewing angle threshold to -45 degrees to the left and +90 degrees to the right, meaning the boom cannot slew more than 45 degrees to the left and cannot slew more than 90 degrees to the right. If there is a high-voltage contact network 8 meters above the construction site, to prevent the boom from touching the contact network during lifting, the user sets the maximum lifting height threshold to 7 meters, leaving a 1-meter safety margin. The control terminal receives and stores these threshold parameters.

[0051] In the above embodiments, during construction operations, angle sensors detect the boom slewing angle of the construction machinery in real time, and height sensors detect the boom lifting height in real time, transmitting the detection data to the control terminal at a frequency of 20 times per second. After receiving the posture sensor information, the control terminal compares the current boom slewing angle and boom lifting height with the user-set thresholds in real time. The control terminal performs graded early warning control of the construction machinery in the following ways: When the boom slewing angle is close to but has not exceeded the maximum boom slewing angle threshold (e.g., the current slewing angle is -40 degrees, the threshold is -45 degrees, and the difference is 5 degrees), the control terminal performs first-level early warning control, displaying "Boom slewing angle: -40 degrees, 5 degrees away from the left limit" (in yellow text) on the visual interface and outputting intermittent prompt sounds to remind the driver to pay attention to the boom slewing angle. When the boom slewing angle exceeds the maximum boom slewing angle threshold (e.g., the current slewing angle is -46 degrees, exceeding the threshold of -45 degrees), the control terminal determines that the preset locking stop condition is met and immediately performs third-level early warning control. Specifically, the control terminal controls the alarm device to output a target alarm signal (the audible alarm sounds "Warning! Boom slewing exceeds limit, please stop immediately!" and the flashing warning light flashes at a high frequency), and displays the risk warning message "Warning! Boom slewing exceeds limit, emergency lock triggered!" (in red text) on the visual interface. Simultaneously, the control terminal outputs a control level to the active stop control circuit, triggering the circuit to perform a forced lock-up operation, causing the construction machinery to enter a locked-down state, preventing the boom from continuing to slew to the left.

[0052] In the above embodiments, similarly, when the boom lifting height exceeds the maximum lifting height threshold (e.g., the current lifting height is 7.2 meters, exceeding the threshold of 7 meters), the control terminal determines that the preset locking condition is met, performs three-level early warning control, controls the alarm device to output a target alarm signal (the audible alarm emits a voice alarm saying "Alarm! Boom lifting exceeds limit, please lower immediately!"), and outputs a control level to the active stop control circuit, causing the construction machinery to enter a locked state, preventing the boom from continuing to lift upwards. In the locked state, the operator can only operate the boom to move in a safe direction (e.g., turn right or lower downwards), and cannot move it in a dangerous direction (e.g., continue to turn left or continue to lift upwards). When the control terminal detects that the boom rotation angle returns to a safe range (e.g., rotates to -40 degrees, less than the threshold of -45 degrees), or the boom lifting height returns to a safe range (e.g., lowers to 6.5 meters, less than the threshold of 7 meters), the control terminal automatically sends an unlock signal to the active stop control circuit, releasing the locked state, and the construction machinery resumes normal operation. Through the aforementioned boom posture limit control, real-time monitoring and limit protection of the boom's rotation angle and lifting height are achieved. Users can flexibly set the boom's operating range according to the actual conditions of the construction site (such as the presence of another power line nearby, overhead overhead contact lines, or surrounding buildings). The intelligent early warning control system automatically monitors the boom's posture, triggering a three-level warning and forcibly locking the boom once it exceeds the set range, effectively preventing the boom from entering dangerous areas. This boom posture limit control function provides effective three-dimensional protection for three-dimensional operations such as boom rotation and lifting, solving the protection problems of special operations such as lifting and excavation.

[0053] In an optional embodiment, the active stop control circuit includes a hydraulic control unit; the hydraulic control unit is used to reduce the output flow of the hydraulic system to zero according to a preset deceleration curve within a preset buffer time after receiving a control level, and disconnect the pilot solenoid valve circuit and pilot oil circuit from the hydraulic system, so that the construction machinery enters a locked-down state; the control terminal is also used to dynamically calculate the preset buffer time and preset deceleration curve according to the current operating speed and load status of the construction machinery, and send the preset buffer time and preset deceleration curve to the hydraulic control unit.

[0054] In the above embodiment, the hydraulic control unit is one of the core components of the active parking control loop, used to control the output flow of the construction machinery's hydraulic system. The hydraulic control unit includes components such as an electro-hydraulic proportional valve, a flow control valve, and a pressure sensor, and can precisely adjust the output flow of the hydraulic system according to control commands sent from the control terminal. The hydraulic control unit is installed in the hydraulic system pipeline of the construction machinery and connected to the pilot solenoid valve circuit, pilot oil circuit, and hydraulic system. The preset buffer time is the time required for the hydraulic control unit to execute the gradual lock-up process, during which the output flow of the hydraulic system gradually decreases from its current value to zero. The preset buffer time is dynamically calculated and determined based on the current operating speed and load status of the construction machinery, and is typically 2-5 seconds. The preset buffer time setting must ensure that the construction machinery can decelerate smoothly, avoiding the impact and danger caused by sudden stops, while also ensuring the timeliness of the lock-up response, ensuring that the construction machinery can stop as quickly as possible after intruding into the parking barrier. The preset deceleration curve is a curve showing the reduction of the hydraulic system's output flow controlled by the hydraulic control unit within the preset buffer time, describing the change in the hydraulic system's output flow over time. The preset deceleration curve can be a linear curve (flow rate decreases at a constant speed), an exponential curve (flow rate decreases rapidly at first, then slowly), or an S-curve (flow rate decreases slowly at first, then rapidly, then slowly again). The preset deceleration curve is dynamically calculated and determined based on the current operating speed and load status of the construction machinery, aiming to achieve a smooth and safe deceleration process. The output flow rate of the hydraulic system refers to the flow rate of hydraulic oil output by the hydraulic system to the actuators (such as hydraulic motors and hydraulic cylinders) of the construction machinery, measured in liters per minute (L / min). The output flow rate of the hydraulic system determines the operating speed and actuation speed of the construction machinery; the higher the output flow rate, the faster the construction machinery operates; when the output flow rate is zero, the construction machinery stops operating.

[0055] In the above embodiments, the control terminal dynamically calculates the preset buffer time and preset deceleration curve based on the current operating speed and load status of the construction machinery. Specifically, the control terminal calculates the current operating speed of the construction machinery (e.g., a travel speed of 2 m / s and a boom rotation speed of 5 degrees / s) using positioning data from the main GNSS positioning module and the slave GNSS positioning module. The control terminal obtains the current load status (e.g., a hydraulic system pressure of 200 bar indicates a heavy load) through the pressure sensor of the hydraulic system. Based on the operating speed and load status, the control terminal determines the preset buffer time and preset deceleration curve using a preset calculation formula or lookup table. For example, when the operating speed is high and the load is heavy, the preset buffer time is set to 5 seconds, and the preset deceleration curve adopts an S-shaped curve, first slowly decelerating (flow rate decreases by 20% in the first 2 seconds), then rapidly decelerating (flow rate decreases by 60% in the middle 2 seconds), and finally slowly decelerating (flow rate decreases by the remaining 20% ​​to zero in the last second), achieving smooth deceleration. When the operating speed is low and the load is light, the preset buffer time is set to 2 seconds, and the preset deceleration curve adopts a linear curve, with the flow rate decreasing uniformly to zero. The control terminal sends the calculated preset buffer time and preset deceleration curve parameters to the hydraulic control unit via the communication line. After receiving these parameters, the hydraulic control unit begins to execute the gradual lock-up process.

[0056] In the above embodiment, within a preset buffer time (e.g., 5 seconds), the hydraulic control unit precisely controls the output flow of the hydraulic system according to a preset deceleration curve (e.g., an S-curve). Specifically, the hydraulic control unit gradually reduces the flow of hydraulic oil entering the pilot solenoid valve by adjusting the opening of the electronically controlled proportional valve. In the first 2 seconds, the output flow of the hydraulic system decreases by 20% from the current value (e.g., 100 L / min) to 80 L / min, and the construction machinery begins to decelerate slowly. In the middle 2 seconds, the output flow of the hydraulic system rapidly decreases by 60% from 80 L / min to 32 L / min, and the construction machinery decelerates significantly. In the last second, the output flow of the hydraulic system slowly decreases from 32 L / min to 0 L / min, and the construction machinery comes to a smooth stop. Throughout the preset buffer time, the hydraulic control unit monitors the output flow of the hydraulic system in real time to ensure that the flow rate decreases precisely according to the preset deceleration curve. If the flow rate deviates from the preset curve, the hydraulic control unit automatically adjusts the opening of the electronically controlled proportional valve to perform closed-loop control, ensuring the smoothness and accuracy of the deceleration process. When the preset buffer time ends and the output flow of the hydraulic system decreases to zero, the hydraulic control unit sends a contact action command to the relay. When the relay contacts actuate, they disconnect the pilot solenoid valve circuit and the pilot oil circuit from the hydraulic system. Specifically, the normally closed contact of the relay opens, de-energizing the pilot solenoid valve, cutting off the pilot oil circuit, and preventing the hydraulic system from supplying oil to the actuators. At this time, the construction machinery enters a locked-down state, and the travel and motion systems (such as the boom and bucket) are completely locked. No operating commands from the operator will be executed, and the construction machinery remains stationary. The control terminal displays the message "Emergency lockout triggered, hydraulic system locked down. Please manually unlock and move in a safe direction" on the visual interface, and records the time, location, and triggering cause of the lockout event for subsequent safety management and accident analysis.

[0057] In an optional embodiment, the system further includes: a manual unlocking device connected to the active parking control circuit; the manual unlocking device is used to receive a user's manual unlocking operation after the construction machinery enters the locked-down state, and send a temporary unlocking signal to the active parking control circuit; the active parking control circuit is used to restore the connection between the pilot solenoid valve circuit and the pilot oil circuit and the hydraulic system after receiving the temporary unlocking signal, and temporarily release the locked-down state; the control terminal is also used to monitor the position change of the construction machinery in real time after the locked-down state is temporarily released, and when the second minimum spatial distance is detected to be greater than the third preset distance threshold, send a confirmation unlocking signal to the active parking control circuit, or when the second minimum spatial distance is detected to be less than the third preset distance threshold, re-output a control level to the active parking control circuit; the active parking control circuit is used to completely release the locked-down state after receiving the confirmation unlocking signal, or to put the construction machinery into the locked-down state after receiving the re-output control level.

[0058] The manual unlocking device is a physical button or switch installed in the cab where it is easily accessible to the driver, or on the outside of the construction machinery where it is convenient for on-site management personnel to operate. The manual unlocking device is connected to the active parking control circuit via a wiring harness. It features anti-accidental operation design, such as using a protective cover, requiring a certain time to trigger, or requiring a password, to prevent accidental operation by the driver or other personnel. The temporary unlock signal is sent to the active parking control circuit by the manual unlocking device after receiving a manual unlocking operation from the user, used to temporarily release the locked state. The temporary unlock signal can be a specific level signal or a digital command. The confirmed unlock signal is sent to the active parking control circuit by the control terminal after determining that the construction machinery has moved to a safe area, used to completely release the locked state. The third preset distance threshold is the distance threshold for determining whether the construction machinery has returned to a safe area, usually set to the second preset distance threshold plus a safety margin (e.g., 5 meters). For example, if the second preset distance threshold is 0 meters (meaning it just touches the parking fence and locks), the third preset distance threshold can be set to 5 meters, meaning that when the construction machinery is 5 meters away from the parking fence, the system determines that the construction machinery has returned to a safe area.

[0059] In the above embodiment, when the construction machinery enters the locked-down state due to meeting the preset locking conditions, the control terminal displays a prompt message on the visual interface: "Emergency lock triggered, hydraulic system locked, please manually unlock and move in a safe direction." Upon seeing the prompt, the driver or site manager first assesses the site situation to confirm that it is safe to move the construction machinery. Then, they operate the manual unlocking device, for example, by pressing and holding the manual unlock button for 3 seconds, or by entering a preset unlocking password. Upon receiving the manual unlocking operation, the manual unlocking device sends a temporary unlocking signal to the active parking control circuit. Upon receiving the temporary unlocking signal, the active parking control circuit de-energizes the relay coil, the relay contacts return to their normally closed state, and the connection between the pilot solenoid valve circuit and the pilot oil circuit and the hydraulic system is restored. The hydraulic control unit stops limiting the output flow of the hydraulic system, and the hydraulic system resumes normal oil supply. At this time, the locked-down state of the construction machinery is temporarily released, the walking system and motion system regain operational capability, and the driver can operate the construction machinery to move in a safe direction away from the parking fence. The control terminal displays a prompt message on the visual interface: "Lock temporarily released, please move immediately in a safe direction, intelligent early warning control system is monitoring."

[0060] In the above embodiment, after the lockout is temporarily released, the control terminal continuously monitors the position changes of the construction machinery in real time. The control terminal acquires the three-dimensional coordinate information of the construction machinery body in real time at a frequency of 20 times per second through the main GNSS positioning module, and calculates the second minimum spatial distance from the three-dimensional spatial outer contour boundary of the construction machinery to the parking fence in real time. Based on the change of the second minimum spatial distance, the control terminal determines whether the construction machinery is moving in a safe direction and whether it has reached a safe area. If the control terminal detects that the second minimum spatial distance gradually increases and exceeds a third preset distance threshold (e.g., 5 meters), it indicates that the construction machinery has moved to a safe area, and the control terminal determines that the conditions for complete unlocking are met. The control terminal immediately sends a confirmation unlocking signal to the active parking control loop. After receiving the confirmation unlocking signal, the active parking control loop completely releases the lockout, and the construction machinery resumes normal operation, no longer restricted by the lockout mechanism. The control terminal displays the message "Construction machinery has returned to the safe area, the lock has been completely released, please pay attention to the safe distance" on the visual interface, and records the details of the unlocking event in the log file, including the unlocking time, unlocking location, unlocking method (manual unlocking), unlocking reason (the second minimum spatial distance is 5.2 meters, and the machinery has returned to the safe area), etc.

[0061] In the above embodiment, if the control terminal detects that after the temporary release of the lockout state, the construction machinery fails to move in a safe direction, or the movement distance is insufficient, the second minimum spatial distance fails to exceed the third preset distance threshold, or even if the second minimum spatial distance decreases again (indicating that the construction machinery is moving in a dangerous direction), the control terminal determines that the construction machinery is still in a dangerous state and does not meet the conditions for complete unlocking. The control terminal immediately re-outputs a control level (high-level signal) to the active stop control circuit. After receiving the re-output control level, the active stop control circuit restarts the lockout procedure. The hydraulic control unit dynamically calculates the preset buffer time and preset deceleration curve based on the current operating speed and load status. Within the preset buffer time, it reduces the output flow of the hydraulic system to zero according to the preset deceleration curve, and then disconnects the pilot solenoid valve circuit and the pilot oil circuit from the hydraulic system, causing the construction machinery to re-enter the lockout state. The control terminal displays the message "Construction machinery has not reached the safe area and has been re-locked. Please manually unlock again and move in a safe direction" on the visual interface. This mechanism ensures that even after the temporary release of the lockout, if the construction machinery fails to truly leave the dangerous area, the system can still re-lock in a timely manner, avoiding the occurrence of safety accidents.

[0062] In the above embodiment, by combining manual unlocking with automatic monitoring, this embodiment successfully solves the physical paradox of the machine being unable to move on its own after being locked. When construction machinery is locked, the hydraulic system is cut off, and the machinery cannot move on its own. Through the manual unlocking device, the driver or site manager can temporarily release the lock, restoring the machinery's mobility. After temporary release, the control terminal continuously monitors the machinery's position, and the lock is only fully released when the machinery has actually moved to a safe area; if the machinery fails to reach a safe area, the intelligent early warning control system relocks it to ensure safety. This ensures both the operability of the intelligent early warning control system (solving the inability to move through manual unlocking) and its security (ensuring full unlocking only under safe conditions through continuous monitoring and conditional judgment), achieving a harmonious balance between safety and operability. Furthermore, the anti-accidental-touch design of the manual unlocking device and the logging of unlocking events further enhance the system's reliability and traceability, providing strong support for construction safety management.

[0063] This application also provides a GNSS-based intelligent early warning control method for construction machinery operating near railway lines, applicable to the intelligent early warning control system of any of the foregoing embodiments. Figure 3 This application provides a flowchart of a GNSS-based intelligent early warning and control method for construction machinery operating near railway lines. The process includes:

[0064] Step S301: In real time, acquire the first three-dimensional coordinate information of the construction machinery vehicle body collected by at least one main GNSS positioning module, and in real time acquire the second three-dimensional coordinate information of the dynamic end point of the construction machinery collected by at least one GNSS positioning module.

[0065] Step S302: Obtain the pose sensing information of the construction machinery collected by the pose sensor;

[0066] Step S303: Based on the first three-dimensional coordinate information, the second three-dimensional coordinate information, the pose sensing information, and the preset mechanical size parameters of the construction machinery, determine the three-dimensional spatial outer contour boundary of the construction machinery, and determine the first minimum spatial distance from the three-dimensional spatial outer contour boundary to the warning fence and the second minimum spatial distance from the three-dimensional spatial outer contour boundary to the parking fence through the three-dimensional position information of the warning fence and the parking fence.

[0067] Step S304: The construction machinery is subjected to graded early warning control through the first minimum spatial distance and the second minimum spatial distance, and the control level is output to the active stop control circuit when the preset lock-up conditions are met.

[0068] Step S305: The construction machinery is subjected to graded early warning control based on the first minimum spatial distance and the second minimum spatial distance, and a control level is output to the active parking control circuit when the preset locking conditions are met.

[0069] Through the above steps, by acquiring the three-dimensional coordinate information of the construction machinery body and dynamic end-point operation point in real time, and combining it with posture sensing information and preset machinery size parameters, the three-dimensional spatial outer contour boundary of the construction machinery is accurately determined, achieving comprehensive perception of the overall spatial position of the construction machinery. By calculating the minimum spatial distance between this three-dimensional spatial outer contour boundary and the warning fence and parking fence, hierarchical early warning control is achieved. When the preset locking stop conditions are met, a control level is automatically output to the active parking control circuit. The active parking control circuit smoothly reduces the hydraulic system output flow to zero according to the preset deceleration curve within a preset buffer time, and then disconnects the pilot solenoid valve circuit and the pilot oil circuit from the hydraulic system, forcing the construction machinery into a locked stop state. This solves the technical problem of poor safety when construction machinery operates near operating lines in related technologies, achieving the technical effect of improving the safety of construction machinery operating near operating lines.

[0070] In an optional embodiment, the three-dimensional position information stored in the control terminal is generated by performing the following steps: when the coordinates of the adjacent business line edge feature points collected by the RTK handheld positioning terminal are obtained, trajectory fitting is performed on the coordinates of the adjacent business line edge feature points to generate a business line baseline; a first preset safety distance and a second preset safety distance are received by the user through the human-computer interaction interface, and three-dimensional position information with a parallel positional relationship to the business line baseline is generated based on the business line baseline, the first preset safety distance and the second preset safety distance.

[0071] In the above embodiment, the process of generating the three-dimensional position information of the warning fence and parking fence stored in the control terminal is described. This generation process is executed during the initialization phase before construction. After acquiring the coordinates of the feature points on the edge of the adjacent operating line collected by the RTK handheld positioning terminal, the control terminal performs trajectory fitting on the coordinates of the feature points on the edge of the adjacent operating line to generate the operating line baseline. Specifically, on-site management personnel or surveyors walk along the edge of the adjacent operating line (such as the outer edge of the railway track) using the RTK handheld positioning terminal, collecting data at a point every 5-10 meters. The RTK handheld positioning terminal uses RTK differential positioning technology to acquire the three-dimensional spatial coordinates (including longitude, latitude, and altitude) of the current location in real time, achieving centimeter-level positioning accuracy. During the data collection process, management personnel ensure that the collected points accurately reflect the actual position and direction of the operating line, especially increasing the density of collection points at key locations such as curves, slope changes, bridges, and tunnels to improve the accuracy of trajectory fitting. After data acquisition, the RTK handheld positioning terminal sends the coordinates of all adjacent service line edge feature points to the control terminal via a wireless network (such as Wi-Fi, 4G / 5G mobile network) or a wired connection (such as a USB data cable). Upon receiving the coordinates, the control terminal stores them in its memory and initiates a trajectory fitting algorithm. The control terminal uses the least squares method to fit the trajectory of the adjacent service line edge feature points. Specifically, the control terminal uses all feature point coordinates as input data and calculates an optimal fitting curve using the least squares method, minimizing the sum of the squared distances from this curve to all feature points. The fitting curve can be a polynomial curve, spline curve, or Bézier curve, etc., with the appropriate curve type selected based on the actual shape of the service line. After fitting, the control terminal generates a service line baseline, which is a continuous and smooth three-dimensional spatial curve that accurately describes the centerline position and direction of the service line, including its planar position (longitude, latitude) and elevation changes (altitude).

[0072] In the above embodiments, the control terminal receives a first preset safety distance and a second preset safety distance input by the user through a human-machine interface. Specifically, the user (such as a construction site safety manager) inputs the first preset safety distance (e.g., 20 meters) and the second preset safety distance (e.g., 10 meters) through a touchscreen or keyboard on the control terminal's human-machine interface. These two safety distance parameters are determined based on railway or highway safety regulations, the actual conditions of the construction site (e.g., the operating speed of the operating line, the type and size of construction machinery, etc.), and safety management requirements. After receiving these two safety distance parameters, the control terminal stores them in its memory. Based on the operating line baseline, the first preset safety distance, and the second preset safety distance, the control terminal generates three-dimensional position information of the warning fence and parking fence that are parallel to the operating line baseline. Specifically, based on the operating line baseline, the control terminal offsets the first preset safety distance (20 meters) along a direction perpendicular to the operating line baseline towards the construction work area (away from the operating line), generating a three-dimensional spatial curve that is parallel to the operating line baseline; this curve is the warning fence. The vertical distance from any point on the warning fence to the baseline of the operating line is 20 meters. The elevation of the warning fence is consistent with the elevation of the baseline of the operating line or adjusted according to the terrain.

[0073] In the above embodiment, similarly, the control terminal offsets itself by a second preset safety distance (10 meters) along a direction perpendicular to the operating line baseline towards the construction work area, generating a parking fence. The vertical distance from any point on the parking fence to the operating line baseline is 10 meters. The parking fence is located between the warning fence and the operating line baseline, forming two electronic safety defense lines. The generated three-dimensional position information of the warning fence and parking fence includes the three-dimensional spatial coordinates (longitude, latitude, altitude) of each point on the fence. This coordinate data is stored in the control terminal's memory in the form of an array or linked list. The control terminal also displays the three-dimensional position information of the warning fence and parking fence graphically on a visualization display screen, forming an intuitive electronic map. The electronic map displays the operating line baseline (e.g., blue curve), warning fence (e.g., yellow curve), parking fence (e.g., red curve), and the real-time position of the construction machinery (e.g., green icon), assisting the driver in intuitively understanding the safe working range and current positional relationship. The control terminal stores the generated three-dimensional position information of the warning fence and parking fence. This three-dimensional position information is permanently stored in the non-volatile memory (such as flash memory or solid-state drive) of the control terminal, and the data will not be lost even if the control terminal is powered off or restarted. During subsequent construction operations, the control terminal reads the three-dimensional position information of the warning fence and parking fence from the memory to calculate the minimum spatial distance between the three-dimensional outer contour boundary of the construction machinery and the fence in real time, so as to realize hierarchical early warning control.

[0074] In an optional embodiment, the construction machinery is subjected to graded early warning control based on a first minimum spatial distance and a second minimum spatial distance, including: when the first minimum spatial distance is less than or equal to a first preset distance threshold, a second-level early warning control is performed to control the alarm device to output a target alarm signal and display risk warning information on the visual interface of the control terminal; when the second minimum spatial distance is less than or equal to a second preset distance threshold, a third-level early warning control is performed to control the terminal to output a control level to the active parking control loop.

[0075] In the above embodiments, the specific process of hierarchical early warning control of construction machinery based on a first minimum spatial distance and a second minimum spatial distance is described. During construction operations, the control terminal calculates the first minimum spatial distance from the three-dimensional spatial outer contour boundary of the construction machinery to the warning fence and the second minimum spatial distance to the parking fence in real time at a frequency of 20 times per second. The control terminal compares these two distance values ​​with preset distance thresholds in real time and executes corresponding early warning control actions based on the comparison results. Level 1 early warning control (prompt): When the first minimum spatial distance is less than a fourth preset distance threshold (e.g., 3 meters) but greater than the first preset distance threshold (e.g., 0 meters, indicating that the warning fence has not been touched), the control terminal performs level 1 early warning control. Specifically, the control terminal outputs an intermittent prompt tone on the visual display screen. The prompt tone is a "beep" sound, which sounds once every 2 seconds. The volume is moderate and will not cause excessive interference to the driver. At the same time, the control terminal changes the color of the first minimum spatial distance number displayed on the visual interface from the normal green to the preset prompt color yellow, for example, displaying "Distance from warning line: 2.35 meters" (yellow text). In addition, the control terminal changes the color of the construction machinery icon from green to yellow on the graphical map of the visual interface, and draws a yellow dashed line between the construction machinery icon and the warning fence, visually displaying the distance relationship between the construction machinery and the warning fence. The first-level warning control is a gentle prompt, designed to remind the driver to maintain a safe distance, giving the driver sufficient time to proactively adjust the position or operating posture of the construction machinery to avoid further approaching the warning fence. During the first-level warning stage, the driver can move the construction machinery away from the warning fence by slowing down, stopping, or adjusting the boom angle or height, thus increasing the first minimum spatial distance. When the first minimum spatial distance increases to a level greater than the fourth preset distance threshold, the control terminal automatically cancels the first-level warning, stops outputting intermittent prompt sounds, restores the distance numerical color to green, and the construction machinery resumes normal operation.

[0076] In the above embodiment, the secondary warning control (alarm) is as follows: When the construction machinery continues to move or operate in the direction of the operating line, and the first minimum spatial distance is less than or equal to the first preset distance threshold (e.g., 0 meters, indicating that the three-dimensional spatial outer contour boundary has just touched or crossed the warning fence), the control terminal determines that the construction machinery has touched or crossed the warning fence and immediately performs secondary warning control. Specifically, the control terminal sends a control command to the alarm device, controlling the alarm device to output a target alarm signal. The audible alarm in the cab immediately emits a high-decibel (e.g., 90-100 decibels) urgent voice alarm, the voice content being "Danger! You have crossed the boundary, please retreat immediately!", the voice is repeated once per second to ensure that the driver can hear it clearly. The flashing warning lights outside the cab begin to flash at a high frequency of 5 times per second, emitting a strong red or yellow warning light signal to remind surrounding personnel and vehicles of the danger. At the same time, the control terminal displays risk warning information on the visual interface. A prominent warning dialog box pops up in the center of the visual interface. The dialog box has a red background and white text, reading "Danger! Boundary crossed, please reverse immediately!" The font size is twice the normal font size to ensure the driver can read it quickly. The control terminal also changes the display color of the first minimum spatial distance to red, for example, displaying "Distance from warning line: -0.5 meters" (red text; a negative value indicates that the warning fence has been crossed by 0.5 meters). On the graphical map of the visual interface, the construction machinery icon changes to red, and a flashing red circle is drawn around the icon, strongly indicating a dangerous situation. The secondary warning control, through strong audible and visual alarms and prominent interface prompts, raises the driver's alertness, prompting immediate action. The driver should immediately stop moving or working towards the operating line and move the construction machinery away from the operating line in a safe direction. When the driver operates the construction machinery to move in a safe direction, the first minimum spatial distance gradually increases. When it exceeds the first preset distance threshold (e.g., from -0.5 meters to 0.5 meters), the control terminal determines that the construction machinery has left the warning fence, automatically cancels the secondary warning control, stops the audible and visual alarm of the alarm device, closes the warning dialog box of the visual interface, and restores the distance number color to yellow or green (depending on whether the current distance is still less than the fourth preset distance threshold).

[0077] In the above embodiment, the three-level early warning control (locking) is as follows: If the driver fails to respond to the second-level early warning in a timely manner, or if the construction machinery continues to move or operate towards the operating line due to operational errors, distraction, or other reasons, and the second minimum spatial distance is less than or equal to the second preset distance threshold (e.g., 0 meters, indicating that the three-dimensional spatial outer contour boundary has just touched or intruded into the parking fence), the control terminal determines that the construction machinery has touched or intruded into the parking fence, meeting the preset locking conditions, and immediately performs the third-level early warning control. Specifically, the control terminal continues to control the alarm device to output the target alarm signal, and the audible alarm emits a more urgent voice alarm, "Alarm! 10-meter warning, please stop!" The voice is repeated twice per second, and the flashing warning light continues to flash at a high frequency. At the same time, the control terminal displays more serious risk warning information on the visual interface, and the content of the warning dialog box changes to "Alarm! Parking line has been intruded, the system will soon forcibly lock!", with the font color in red and the background flashing. Simultaneously, the control terminal immediately outputs a control level (high-level signal, such as 12V or 24V DC voltage) to the active parking control circuit. Upon receiving the control signal, the active stop control circuit energizes the relay coil, triggering the hydraulic control unit to initiate a gradual stop procedure. The control terminal dynamically calculates the preset buffer time (e.g., 2-5 seconds) and the preset deceleration curve (e.g., S-curve or linear curve) based on the current operating speed and load status of the construction machinery. The control terminal sends these parameters to the hydraulic control unit. Within the preset buffer time, the hydraulic control unit precisely controls the output flow of the hydraulic system according to the preset deceleration curve, gradually reducing the output flow from its current value to zero. Throughout the deceleration process, the construction machinery decelerates smoothly, avoiding the dangers of sudden hydraulic shock, sudden changes in structural stress, boom inertial swaying, load fall, and driver inertial injury that could result from a sudden stop.

[0078] In the above embodiment, when the preset buffer time ends and the output flow of the hydraulic system drops to zero, the hydraulic control unit sends a contact action command to the relay. The relay contacts actuate, cutting off the connection between the pilot solenoid valve circuit and the pilot oil circuit and the hydraulic system. At this time, the construction machinery enters a locked-down state, and the walking system and motion system (such as the boom, bucket, slewing mechanism, etc.) are completely locked. No operation commands from the driver will be executed, and the construction machinery remains stationary. The control terminal displays the message "Emergency lockout triggered, hydraulic system locked down, please operate to unlock in a safe direction" on the visual interface, and records detailed information about the lockout event, including the lockout time (e.g., January 15, 14:35:22), lockout location (three-dimensional coordinates of the construction machinery), triggering reason (second minimum spatial distance is -0.3 meters, intrusion into the parking fence by 0.3 meters), current operating speed (e.g., 1.5 m / s), load status (e.g., hydraulic system pressure 180 bar), etc. This information is stored in the control terminal's log file for subsequent safety management, accident analysis, and liability determination.

[0079] In the above embodiment, the unlocking process is as follows: After the construction machinery enters the locked-off state, the driver needs to move the machinery in a safe direction away from the parking barrier to unlock it. The driver can achieve this in the following ways: Method 1: If the construction machinery is locked due to its walking system intruding into the parking barrier, the driver can get out of the vehicle and organize on-site personnel or use a tow truck to move the machinery backward (away from the parking barrier). Method 2: If the construction machinery is locked due to its boom rotating or lifting intruding into the parking barrier, the driver can operate the boom to move in a safe direction (e.g., rotate in the opposite direction or lower it). After the control terminal detects that the driver's operation command is in a safe direction, it temporarily releases the lock on that direction, allowing the boom to move in that direction. The control terminal continuously monitors the position changes of the construction machinery in real time. When the control terminal detects that the construction machinery is moving in a safe direction away from the parking barrier, and the second minimum spatial distance gradually increases, exceeding the third preset distance threshold (e.g., 5 meters), the control terminal determines that the construction machinery has returned to a safe area, meeting the automatic unlocking conditions. The control terminal immediately sends an unlock signal to the active parking control loop. Upon receiving the unlock signal, the active parking control circuit de-energizes the relay coil, and the relay contacts return to their normally closed state. This restores the connection between the pilot solenoid valve circuit and the pilot oil circuit with the hydraulic system. The hydraulic control unit ceases to restrict the hydraulic system's output flow, and the hydraulic system resumes normal oil supply. At this point, the construction machinery is unlocked, and the travel and motion systems resume normal operation, allowing the operator to continue working. The control terminal displays a message on the visual interface: "Lock released, construction machinery has resumed normal operation. Please maintain a safe distance to avoid triggering the lock again." Detailed information about the unlocking event is recorded in the log file, including the unlocking time, unlocking location, and unlocking reason (the second minimum spatial distance is 5.2 meters, and the operator has returned to a safe area).

[0080] In the above embodiment, through the hierarchical control of Level 1 (prompt), Level 2 (alarm), and Level 3 (lockdown), a complete risk control closed loop is formed: Level 1 provides a mild prompt when construction machinery approaches the warning fence, giving the driver an opportunity to make proactive adjustments; this is the first line of defense. Level 2 provides a strong alarm when construction machinery touches or crosses the warning fence, raising the driver's alertness through audible and visual signals and interface prompts, prompting the driver to take immediate action; this is the second line of defense. Level 3 forcibly locks the construction machinery when it touches or intrudes into the parking fence. Even in the extreme case where the driver fails to respond to Level 2 warnings in time, forced locking prevents the construction machinery from further intruding into the operational safety clearance; this is the last line of defense, ensuring the safety of construction operations.

[0081] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods according to the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0082] This application also provides a computer-readable storage medium storing instructions that, when executed, perform the steps of any of the methods described above.

[0083] In one exemplary embodiment, the aforementioned computer-readable storage medium may include, but is not limited to, various media capable of storing computer programs, such as a USB flash drive, read-only memory (ROM), random access memory (RAM), portable hard disk, magnetic disk, or optical disk.

[0084] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0085] In the various embodiments provided in this application, it should be understood that the disclosed apparatus can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some service interface; the indirect coupling or communication connection between apparatuses or units may be electrical or other forms.

[0086] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0087] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0088] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage device (CMD). Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned memory includes various media capable of storing program code, such as USB flash drives, portable hard drives, magnetic disks, or optical disks.

[0089] The above description is merely an exemplary embodiment of this disclosure and should not be construed as limiting the scope of this disclosure. Any equivalent changes and modifications made in accordance with the teachings of this disclosure shall still fall within the scope of this disclosure. Other embodiments of this disclosure will be readily apparent to those skilled in the art upon consideration of the disclosure herein.

[0090] This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art that are not described in this disclosure.

Claims

1. A GNSS-based intelligent early warning control system for construction machinery operating near railway lines, characterized in that, It includes a control terminal, and at least one master GNSS positioning module, at least one slave GNSS positioning module, a pose sensor, and an active parking control loop, all of which are communicatively connected to the control terminal; wherein, At least one main GNSS positioning module is installed on the body of the construction machinery to acquire the first three-dimensional coordinate information of the body in real time. The at least one GNSS positioning module is installed at the dynamic end point of the construction machinery to acquire the second three-dimensional coordinate information of the dynamic end point in real time. The pose sensor is used to collect pose sensing information of the construction machinery; The control terminal is used to determine the three-dimensional spatial outer contour boundary of the construction machinery through the first three-dimensional coordinate information, the second three-dimensional coordinate information, the pose sensing information and the preset mechanical size parameters of the construction machinery, and to determine the first minimum spatial distance from the three-dimensional spatial outer contour boundary to the warning fence and the second minimum spatial distance from the three-dimensional spatial outer contour boundary to the parking fence through the three-dimensional position information of the warning fence and the parking fence. The control terminal is also used to perform graded early warning control on the construction machinery based on the first minimum spatial distance and the second minimum spatial distance, and to output a control level to the active parking control loop when it is determined that the preset locking conditions are met. The active stop control circuit is used to receive the control level and disconnect the pilot solenoid valve circuit and pilot oil circuit on the construction machinery from the hydraulic system through the control level, so that the construction machinery in dynamic operation enters the lock-up state until it receives the unlock signal.

2. The system according to claim 1, characterized in that, The system also includes: an RTK handheld positioning terminal that is communicatively connected to the control terminal; The RTK handheld positioning terminal is used to collect point data at the construction site before construction, determine the coordinates of the adjacent operating line edge feature points based on the point data, and send the coordinates of the adjacent operating line edge feature points to the control terminal. The control terminal is also used to receive the coordinates of the feature points on the edge of the adjacent business line, perform trajectory fitting on the coordinates of the feature points on the edge of the adjacent business line, and generate a baseline of the business line. The control terminal is also used to receive a first preset safety distance and a second preset safety distance input by the user through the human-computer interaction interface, and to generate the three-dimensional position information that has a parallel positional relationship with the business line baseline based on the business line baseline, the first preset safety distance and the second preset safety distance; The control terminal is also used to store the three-dimensional position information.

3. The system according to claim 1, characterized in that, The system also includes an alarm device that is communicatively connected to the control terminal; The control terminal performs graded early warning control on the construction machinery in the following ways: When the first minimum spatial distance is less than or equal to the first preset distance threshold, the control terminal performs a secondary early warning control to control the alarm device to output a target alarm signal and display risk warning information on the visual interface of the control terminal. When the second minimum spatial distance is less than or equal to the second preset distance threshold, the control terminal performs a three-level early warning control to output the control level to the active parking control loop.

4. The system according to claim 1, characterized in that, The pose sensor includes an angle sensor and a height sensor; The angle sensor is installed on the construction machinery and is used to detect the boom rotation angle of the construction machinery. The height sensor is installed on the construction machinery and is used to detect the lifting height of the boom of the construction machinery; The control terminal performs graded early warning control on the construction machinery in the following ways: The control terminal is also used to receive the maximum slewing angle threshold and the maximum lifting height threshold set by the user through the human-machine interface, and to perform three-level early warning control when the slewing angle of the boom exceeds the maximum slewing angle threshold or the lifting height of the boom exceeds the maximum lifting height threshold, so as to output the control level to the active stop control loop.

5. The system according to claim 1, characterized in that, The active parking control circuit includes a hydraulic control unit; The hydraulic control unit is used to reduce the output flow of the hydraulic system to zero according to the preset deceleration curve within a preset buffer time after receiving the control level, and to disconnect the connection between the pilot solenoid valve circuit and the pilot oil circuit and the hydraulic system, so that the construction machinery enters the lock-up state. The control terminal is also used to dynamically calculate the preset buffer time and preset deceleration curve based on the current operating speed and load status of the construction machinery, and send the preset buffer time and preset deceleration curve to the hydraulic control unit.

6. The system according to claim 5, characterized in that, The system also includes a manual unlocking device connected to the active parking control loop; The manual unlocking device is used to receive the user's manual unlocking operation after the construction machinery enters the locked stop state, and to send a temporary unlocking signal to the active parking control circuit. The active stop control circuit is used to restore the connection between the pilot solenoid valve circuit and the pilot oil circuit and the hydraulic system after receiving the temporary unlock signal, and temporarily release the lock-up state. The control terminal is also used to monitor the position change of the construction machinery in real time after the lock-stop state is temporarily released, and when the second minimum spatial distance is detected to be greater than the third preset distance threshold, send a confirmation unlock signal to the active parking control circuit, or when the second minimum spatial distance is detected to be less than the third preset distance threshold, re-output the control level to the active parking control circuit. The active parking control circuit is used to completely release the locked state after receiving the confirmation unlock signal, or to put the construction machinery into the locked state after receiving the re-output control level.

7. A GNSS-based intelligent early warning and control method for construction machinery operating near railway lines, characterized in that, The system applied to any one of claims 1 to 6 includes: The first three-dimensional coordinate information of the construction machinery vehicle body collected by at least one main GNSS positioning module is acquired in real time, and the second three-dimensional coordinate information of the dynamic end point of the construction machinery collected by at least one GNSS positioning module is acquired in real time. Acquire the pose sensing information of the construction machinery collected by the pose sensor; Based on the first three-dimensional coordinate information, the second three-dimensional coordinate information, the pose sensing information, and the preset mechanical size parameters of the construction machinery, the three-dimensional spatial outer contour boundary of the construction machinery is determined, and the first minimum spatial distance from the three-dimensional spatial outer contour boundary to the warning fence and the second minimum spatial distance from the three-dimensional spatial outer contour boundary to the parking fence are determined through the three-dimensional position information of the warning fence and the parking fence. The construction machinery is subjected to graded early warning control by the first minimum spatial distance and the second minimum spatial distance, and a control level is output to the active parking control loop when the preset locking and stopping conditions are met. When the control level is received, the connection between the pilot solenoid valve circuit and the pilot oil circuit on the construction machinery and the hydraulic system is cut off through the active stop control circuit, so that the construction machinery in dynamic operation enters the lock-up state until the unlock signal is received.

8. The method according to claim 7, characterized in that, The three-dimensional position information stored in the control terminal is generated by performing the following steps: If the coordinates of the feature points on the edge of the adjacent business line are obtained from the RTK handheld positioning terminal, the coordinates of the feature points on the edge of the adjacent business line are fitted to generate the business line baseline. The system receives a first preset safety distance and a second preset safety distance input by the user through a human-computer interaction interface, and generates three-dimensional position information that has a parallel positional relationship with the business line baseline based on the business line baseline, the first preset safety distance, and the second preset safety distance.

9. The method according to claim 7, characterized in that, The method of performing graded early warning control of the construction machinery based on the first minimum spatial distance and the second minimum spatial distance includes: When the first minimum spatial distance is less than or equal to the first preset distance threshold, a secondary early warning control is performed to control the alarm device to output a target alarm signal and display risk warning information on the visual interface of the control terminal. When the second minimum spatial distance is less than or equal to the second preset distance threshold, a three-level early warning control is performed, and the control terminal outputs the control level to the active parking control loop.

10. A computer-readable storage medium comprising instructions, characterized in that, When the instruction is executed on the intelligent early warning control system, the intelligent early warning control system performs the method as described in any one of claims 7-9.

Images