Coal mine temporary support control system based on PLC

Abstract

The invention relates to the technical field of coal mines, in particular to a coal mine temporary support control system based on a PLC, and the system comprises an environment sensing module which is located under a coal mine and obtains the working condition data of the environment during the operation of support equipment in real time; the PLC main controller is used for performing analysis according to the working condition data, obtaining the posture adjustment amount and the safety risk level of the current supporting equipment operation, and determining the working mode of the supporting control module of the supporting equipment according to the safety risk level; the support control module is used for enabling an oil cylinder control unit to which the working mode belongs to generate a driving signal for driving support equipment based on the posture adjustment amount and / or response information according to the working mode and the posture adjustment amount output by the PLC main controller; and the supporting structure is used for driving supporting equipment to complete pushing, positioning and mounting operation on the temporary supporting bracket based on the driving signal. The technical problems that temporary shed frame installation has potential safety hazards and is high in uncertainty are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of coal mines, and particularly relates to a coal mine temporary support control system based on PLC. BACKGROUND

[0002] In coal mining operations, a temporary support structure needs to be set up before the permanent support is erected in the underground tunneling working face to prevent the roadway from collapsing and to protect the lives and safety of the tunneling construction personnel. The coal mine temporary support control system is the core equipment for achieving this safety protection goal. The core function of this system is to monitor the running state of the temporary support structure in real time and to accurately control it, so as to prevent the occurrence of mine collapse, roof falling and other serious accidents.

[0003] In the prior art, the operation of the temporary support control system relies on the monitoring device to collect the relevant data of the roadway environment and the support structure. These data need to be preliminarily processed by the data acquisition equipment and then transmitted to the ground monitoring center by means of wired or wireless communication technologies such as Ethernet and wireless sensor networks, so that the staff can master the underground support situation in real time. However, the current support operation of the temporary shed frame is still dominated by manual support, mainly because the internal environment of the coal mine roadway is extremely complex, with many unfavorable factors such as fluctuating floor, narrow space, high dust concentration and strong electromagnetic interference, which makes it difficult for the existing technology to break through the technical bottleneck of automatic installation and unable to realize the automatic erection and accurate control of the temporary shed frame.

[0004] Therefore, there is an urgent need for a coal mine temporary support control system based on PLC. SUMMARY

[0005] (I) Technical problems to be solved

[0006] In view of the above-mentioned shortcomings and deficiencies of the prior art, the present application provides a coal mine temporary support control system based on PLC, which solves the technical problems of uncertain system operation and certain safety hazards in manual installation of the temporary shed frame in the prior art.

[0007] (II) Technical solutions

[0008] In order to achieve the above-mentioned purposes, the main technical solutions adopted by the present application include:

[0009] The present application provides a coal mine temporary support control system based on PLC, which comprises:

[0010] An environment perception module is located in the coal mine underground and acquires the working condition data of the environment during the operation of the support equipment in real time.

[0011] The PLC main controller is configured to analyze the working condition data, obtain a posture adjustment amount and a safety risk level of the current support equipment operation, and determine a working mode of the support control module of the support equipment according to the safety risk level;

[0012] The support control module is configured to make the working mode belong to the oil cylinder control unit generate a driving signal for driving the support equipment based on the posture adjustment amount and / or response information according to the working mode and the posture adjustment amount output by the PLC main controller, the response information being information generated based on a response to an operation instruction input by an external remote control device;

[0013] The support structure is configured to drive the support equipment to complete a pushing, positioning and installation operation on the temporary support support based on the driving signal.

[0014] Optionally, in some embodiments of the present application, the environment perception module comprises:

[0015] a visual sensor, an ultrasonic sensor, a pressure sensor, an angle sensor, an encoder and a laser radar;

[0016] The environment perception module collects working condition data including real-time position, real-time pitch angle and travel direction of the support equipment, anchor rod position and center point position of the temporary support support, obstacle information, support equipment top strata displacement data and temporary support support pressure data.

[0017] Optionally, in some embodiments of the present application, the PLC main controller comprises:

[0018] The posture adjustment analysis unit is configured to compare and analyze the real-time pitch angle and travel direction of the support equipment with a historical motion trajectory, obtain a slope of posture change and a lateral offset amount, and generate a posture adjustment amount according to the slope of posture change and the lateral offset amount;

[0019] The prediction safety analysis unit is configured to analyze the support equipment top strata displacement data and the temporary support support pressure data based on a roof separation prediction model and a hydraulic support bearing limit model, and obtain a safety risk level;

[0020] The mode arbitration unit is configured to arbitrate the working mode according to the safety risk level; when the safety risk level is high risk, the arbitration is manual working mode; when the safety risk level is medium risk, the arbitration is to maintain the current working mode; and when the safety risk level is low risk, the arbitration is automatic working mode.

[0021] Optionally, in some embodiments of the present application, the posture adjustment analysis unit is specifically configured to:

[0022] linear fitting is performed on the real-time pitch angle data collected by the angle sensor and the encoder within a set time window, and a slope of a straight line obtained by the fitting is taken as a pitch angle change rate representing a dynamic change trend of the pitch posture of the equipment;

[0023] By fusing the real-time position data of the encoder and the laser radar, a vertical distance from a current position of the support equipment to a preset ideal trajectory fitted by the historical motion trajectory is obtained as a lateral deviation;

[0024] The pitch angle change rate and the lateral deviation are compared with dynamic thresholds established based on historical data, and the posture adjustment amount is generated according to a comparison result.

[0025] Optionally, in some embodiments of the present application, the prediction safety analysis unit is specifically configured to:

[0026] The roof strata displacement data is input into the roof separation prediction model to obtain a predicted value of the roof separation amount, and the temporary support support pressure data is input into the hydraulic support load limit model to obtain a ratio of a current load of the support to a rated load;

[0027] When the predicted value of the roof separation amount exceeds a separation early warning threshold or the load ratio exceeds a load capacity early warning threshold, a safety risk level is output as high risk;

[0028] When the predicted value of the roof separation amount is within a first proximity range of the separation early warning threshold without exceeding the separation early warning threshold, and / or the load ratio is within a second proximity range of the load capacity early warning threshold without exceeding the load capacity early warning threshold, the safety risk level is output as medium risk;

[0029] When the predicted value of the roof separation amount is lower than the separation early warning threshold and the load ratio is lower than the load capacity early warning threshold, the safety risk level is output as low risk.

[0030] Optionally, in some embodiments of the present application, the support control module includes an oil cylinder automatic control unit and an oil cylinder manual control unit arranged in parallel;

[0031] In the automatic working mode, the PLC main controller sends an instruction to start the oil cylinder automatic control unit to the oil cylinder automatic control unit, so that the oil cylinder automatic control unit generates a driving signal according to a preset program sequence based on the posture adjustment amount;

[0032] In the manual working mode, the PLC main controller sends an instruction to start the oil cylinder manual control unit to the oil cylinder manual control unit, so that the oil cylinder manual control unit receives response information and maps the response information as a driving signal.

[0033] Optionally, in some embodiments of the present application, the support control module further comprises a visual camera marking unit;

[0034] The visual camera marking unit comprises an industrial camera and an ArUcoMarker binary square marker, which are installed on the shed moving mechanism and the shed installation mechanical arm, respectively;

[0035] The ArUcoMarker binary square marker is fixed below the center of the top beam of the temporary support support, and carries digital code information of the support;

[0036] The oil cylinder automatic control unit is signal connected with the visual camera marking unit;

[0037] In the automatic working mode, the oil cylinder automatic control unit calls the visual camera marking unit to obtain the center point pose of the temporary support support by identifying the ArUcoMarker binary square marker, generates the centering adjustment data for accurate positioning, and fuses the centering adjustment data with the attitude adjustment amount to generate a driving signal.

[0038] Optionally, in some embodiments of the present application, the support structure comprises a driving element and a limit protection element;

[0039] The driving element comprises a motor and an oil cylinder, and the support equipment comprises a shed moving mechanism and a shed installation mechanical arm;

[0040] The motor is used to drive the shed moving mechanism to move the temporary support support to a designated working position in the well; the oil cylinder is provided with 6 groups of 12 cylinders, which are symmetrically distributed on both sides of the shed installation mechanical arm, and is used to drive the shed installation mechanical arm to perform precise positioning and installation of the temporary support support;

[0041] The limit protection element comprises a first limit switch and a second limit switch, the first limit switch is installed at the starting point and the ending point of the motor-driven shed moving mechanism, and the second limit switch is installed at the ending point of the telescopic stroke of each oil cylinder.

[0042] Optionally, in some embodiments of the present application, the first limit switch is used to detect the limit motion position of the shed moving mechanism: when the shed moving mechanism drives the temporary support support to the designated working position in the well, the first limit switch is triggered, and the motor stops running;

[0043] The second limit switch is used to detect the ending point of the telescopic stroke of the oil cylinder: when the oil cylinder drives the shed installation mechanical arm to move to the designed installation position of the temporary support support, the second limit switch is triggered, and the oil cylinder stops moving.

[0044] Optionally, in some embodiments of the present application, the external remote control device is signal connected with the oil cylinder manual control unit, and the external remote control device is provided with physical buttons corresponding to the forward and backward actions of each oil cylinder and an independent emergency stop button.

[0045] (Three) beneficial effects

[0046] The beneficial effects of the present application are: the PLC-based coal mine temporary support control system of the present application can realize real-time monitoring of underground support work, precise regulation and control of support posture, dynamic prevention and control of safety risks, and flexibility of automatic work and manual remote control operation, effectively reduce the intensity of manual intervention and the safety hazards of work, improve the work efficiency and precision of temporary support bracket movement, positioning and installation, and achieve the technical effects of intelligentization, safety and high efficiency of temporary support work in coal mines, adapt to complex and changeable underground working environment, and ensure the reliability and safety of support work. BRIEF DESCRIPTION OF DRAWINGS

[0047] Figure 1 is a structural diagram of a PLC-based coal mine temporary support control system according to an embodiment of the present application;

[0048] Figure 2 is a detailed structural diagram of a PLC-based coal mine frame temporary support control system according to an embodiment of the present application. DETAILED DESCRIPTION

[0049] In order to better explain the present application and facilitate understanding, the present application is described in detail in the specific implementation mode combined with the accompanying drawings.

[0050] In the process of tunneling in coal mine, temporary support is the key link to ensure the safety of operation. Its role is to support the exposed roof and surrounding rock in time before the erection of permanent support, so as to prevent roof fall, rib spalling and other safety accidents. At present, in many coal mines, the installation, pushing and positioning of temporary support are still highly dependent on manual operation or low degree of mechanization control. The operator needs to control the hydraulic cylinder and other actuators in close proximity in the complex and dangerous tunnel environment to complete the erection of the shed frame. This way not only is inefficient, making it difficult for the support speed to match the demand for rapid tunneling, but more importantly, the entire support process is full of uncertainty. The practice of manual judgment of roof condition and manual control of support posture is extremely easy to cause problems such as inadequate support, poor contact between support and roof, etc. due to individual experience differences, reaction delays or operation errors, which may cause serious safety hazards.

[0051] Although some attempts have been made in the prior art to improve the level of support mechanization, such as using simple program control or remote control, these systems often have single functions and lack comprehensive perception and intelligent decision-making ability in complex underground environments. They usually cannot monitor the running posture of the support equipment in real time and accurately, nor can they make predictive safety analysis of the stability of the roof strata. Their control mode is mostly fixed automatic or manual, and cannot dynamically switch and arbitrate according to the risk level of the actual working conditions. When encountering unexpected situations or complex geological conditions, the system has poor self-adaptability and still needs personnel intervention, failing to fundamentally solve the contradiction between automation and safety. In addition, the key steps in the support process, such as the precise centering installation of the support, still lack effective visual auxiliary positioning means, affecting the final quality and reliability of the support.

[0052] Therefore, there is an urgent need in the art for a temporary support control system that integrates intelligent perception, real-time analysis, dynamic decision-making and precise control. It should be able to overcome the excessive dependence on manual experience in the prior art, solve the problem of difficult to balance automation and safety, and thus achieve overall improvement in efficiency, accuracy and intrinsic safety of support operation.

[0053] Therefore, the PLC-based coal mine temporary support control system provided in the embodiments of the present application comprehensively collects working condition data through an environment perception module; a PLC main controller is used as a decision center to not only analyze the posture of the support equipment in real time and generate adjustment instructions, but also perform forward-looking assessment on potential risks through a built-in predictive safety model, such as a roof separation prediction model and a hydraulic support bearing limit model, and determine the optimal working mode according to the arbitration result; finally, the support control module determines whether to call the oil cylinder automatic control unit to realize accurate positioning in combination with visual recognition technology or to switch to the oil cylinder manual control unit to respond to remote operation, so as to drive the support structure to complete the support work with high precision and high safety. The present application significantly improves the intelligent level, safety and reliability, and work efficiency of the temporary support process, and represents a new direction of the development of the field.

[0054] In order to better understand the above technical solutions, the exemplary embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided so that the present application can be more clearly, thoroughly understood, and the scope of the present application can be completely conveyed to those skilled in the art.

[0055] Embodiment 1

[0056] Figure 1 The structure diagram of the PLC-based coal mine temporary support control system according to an embodiment of the present application. As Figure 1 The PLC-based coal mine temporary support control system comprises:

[0057] The environment perception module is located in the coal mine and acquires working condition data of the environment during the operation of the support equipment in real time, including:

[0058] The visual sensor, the ultrasonic sensor, the pressure sensor, the angle sensor, the encoder, and the laser radar;

[0059] The environment perception module collects working condition data including the real-time position, the real-time pitch angle, and the traveling direction of the support equipment, the anchor rod position and the center point position of the temporary support support, the obstacle information, the rock layer displacement data at the top of the support equipment, and the pressure data of the temporary support support.

[0060] Specifically, the environment perception module can be specifically refined into the following aspects: first, the pose and motion state of the support equipment itself, the real-time pitch angle, the travel distance and direction of the support equipment are obtained in real time through the angle sensor and the encoder, and the basic motion trajectory is tracked. In order to further improve the spatial positioning accuracy, the laser radar scans the roadway profile and matches with the preset map, so as to accurately calculate the real-time position of the equipment and effectively detect the obstacle information on the travel path. Secondly, for the core target of the support operation, the visual sensor is responsible for identifying the visual features of the support, so as to locate the anchor rod position and the center point, and provide visual guidance for the subsequent installation of the mechanical arm of the shed frame. Finally, for the key parameters related to the operation, specific sensors are used for monitoring: the pressure sensor monitors the pressure data of the temporary support support in real time to evaluate the stress state of the support structure; and by analyzing the time sequence scanning data of the laser radar or cooperating with the special displacement sensor, the displacement data of the top rock layer of the support equipment can be indirectly obtained, so as to analyze the stability of the roof.

[0061] The environment perception module realizes the comprehensiveness of the perception dimension and the efficiency of the data coupling by setting the above-mentioned various sensors. The system not only perceives the self-state of the support equipment, but also synchronously perceives the state of the temporary support support and the state of the surrounding environment, and places the three information in the same space-time reference, thereby providing a global view for the PLC main controller. In addition, the position information of the support equipment comes from both the odometer calculation of the encoder and the absolute positioning of the laser radar, which can be corrected with each other, thereby improving the positioning reliability and laying an indispensable data cornerstone for the subsequent intelligent attitude adjustment, prospective safety risk prediction and optimal work arbitration of the PLC main controller.

[0062] The PLC main controller is used for analyzing the working condition data, obtaining the attitude adjustment amount and the safety risk level of the current support equipment operation, and determining the working mode of the support control module of the support equipment according to the safety risk level.

[0063] The PLC main controller comprises:

[0064] The attitude adjustment analysis unit is used for comparing and analyzing the real-time pitch angle and the travel direction of the support equipment with the historical motion trajectory, obtaining the slope of the attitude change and the lateral offset, and generating the attitude adjustment amount according to the slope of the attitude change and the lateral offset.

[0065] The attitude adjustment analysis unit is specifically used for:

[0066] In a set time window, the real-time pitch angle data collected by the angle sensor and the encoder is linearly fitted, and the slope of the straight line obtained by fitting is taken as the pitch angle change rate representing the dynamic change trend of the equipment pitch attitude.

[0067] By fusing the encoder with real-time position data of the laser radar, the vertical distance between the current position of the support equipment and the preset ideal trajectory fitted by the historical motion trajectory is obtained as the lateral offset;

[0068] The pitch angle change rate and the lateral offset are compared with the dynamic threshold established based on historical data, and the posture adjustment amount is generated according to the comparison result.

[0069] In the pitch angle change rate calculation link, the limitation of traditional fixed time window is broken through, and an adaptive time window dynamic adjustment strategy is adopted, which intelligently adjusts the time window length of data fitting according to the real-time running speed of the support equipment (converted by encoder data acquisition) and the pitch angle fluctuation amplitude:

[0070] When the equipment running speed ≥ 0.5 m / s or the pitch angle fluctuation amplitude ≥ 0.3° / s, the time window is shortened to 0.5 s to improve the response speed to posture mutation; when the equipment running speed < 0.5 m / s and the pitch angle fluctuation amplitude < 0.3° / s, the time window is expanded to 1.5 s to improve the stability of the fitting result. Based on the optimized time window, the least square method is used to linearly fit the preprocessed real-time pitch angle data, not only to obtain the slope of the fitted straight line as the pitch angle change rate, but also to verify the reliability of the data trend by calculating the fitting goodness R 2 (R 2 ≥ 0.9), if R 2 < 0.9, data reacquisition and secondary fitting are automatically triggered to ensure the accuracy of the posture dynamic change trend representation.

[0071] In terms of lateral offset calculation, a multi-source positioning data weighted fusion mechanism is adopted, and the federal Kalman filter algorithm is used to fuse the encoder's mileage positioning data and the laser radar's environment perception positioning data, and the fusion weight is dynamically allocated according to the real-time confidence of the two sensors:

[0072] For example, when the laser radar occlusion rate < 20%, give it 60% weight, and the encoder gives 40% weight; when the laser radar occlusion rate ≥ 20%, automatically increase the encoder weight to 70%, and the laser radar weight to 30%, thereby effectively avoiding the influence of single sensor positioning deviation.

[0073] After the pitch angle change rate and the lateral offset are obtained, the pitch angle change rate and the lateral offset are compared with dynamic thresholds obtained based on historical data, when the pitch angle change rate or the lateral offset exceeds 70% of the dynamic threshold, it is marked as a "caution" state and the trend is continuously monitored, when the pitch angle change rate or the lateral offset further exceeds 85% of the dynamic threshold, it is upgraded to an "adjustment required" state, and once the pitch angle change rate or the lateral offset shows an accelerating deviation trend, an "emergency" state is triggered immediately.

[0074] According to the state evaluation result, an adaptive gain coefficient is obtained, and the final attitude adjustment amount is the product of the basic adjustment amount and the adaptive gain coefficient.

[0075] The adaptive gain coefficient is determined by the current motion phase and the state evaluation result. In the non-emergency state, a smaller gain is used in the start / brake phase to ensure smoothness, and a larger gain is used in the uniform speed phase to ensure response speed; when the system is in the "caution" state, the gain should be further reduced based on the current motion phase gain to suppress unnecessary disturbance; and when the "emergency" state is triggered, the system will enable a specially designed emergency attitude adjustment gain, which is usually higher than the uniform speed phase gain to ensure rapid suppression of risks.

[0076] For example, if the lateral offset of the support equipment reaches 72% of the dynamic threshold within 0.5s, it is marked as "caution". Since it is in the caution state, the system uses 0.8 times the uniform speed gain based on the larger gain in the uniform speed phase, and at this time, the final attitude adjustment amount is 0.8 times the basic adjustment amount.

[0077] Optionally, the PLC main controller of the present application adopts structured programming, and the program is modularized. The entire program can be divided into eight modules: PLC power-on initialization, Modbus communication, input signal conversion, automatic control of oil cylinder, manual control of oil cylinder, motor control, emergency stop control and timeout control. Among them, the PLC power-on initialization, Modbus communication, input signal conversion, emergency stop control and timeout control are integrated in the Main function block of the program block, and the remaining modules have their own independent function blocks. The advantage of structured programming is that the subprogram blocks can be conveniently called in the main program block, and the program structure is clear. For example, the timeout module in the PLC refers to that the PLC main controller sets a timeout timer for each oil cylinder action, if the first limit switch or the second limit switch is not triggered within the set time, the PLC main controller determines that it is a timeout fault, at this time, the current installation process is stopped.

[0078] The adaptive time window dynamic adjustment strategy adopted in the pitch angle change rate calculation link of the embodiment of the application can flexibly adapt the window length according to the real-time running speed of the support equipment and the pitch angle fluctuation amplitude, which not only solves the problems of response lag when the equipment posture suddenly changes and insufficient fitting stability when running smoothly of the traditional fixed time window, but also effectively eliminates abnormal data interference through the least square fitting combined with the fitting goodness R² verification mechanism, ensuring that the posture dynamic trend represented by the pitch angle change rate is real and reliable. The multi-source positioning data weighted fusion mechanism based on federated Kalman filtering adopted in the lateral offset calculation can dynamically assign the fusion weights of the encoder and the laser radar according to the real-time confidence such as the laser radar shielding rate, completely avoiding the defects that the positioning of a single sensor is easily disturbed by the environment and has a large deviation, and significantly improving the anti-interference ability and precision of the positioning data. The above technical designs work together, not only greatly improving the calculation accuracy, timeliness and reliability of the pitch angle change rate and the lateral offset, but also adapting to the complex and changeable working environment and equipment running state in the coal mine, providing high-quality data support for the PLC main controller to generate accurate and reasonable posture adjustment amount subsequently.

[0079] The prediction safety analysis unit is configured to analyze the roof strata displacement data and the temporary support support pressure data based on the roof separation prediction model and the hydraulic support bearing limit model, and obtain a safety risk level.

[0080] The prediction safety analysis unit is specifically configured to:

[0081] The roof strata displacement data is input into the roof separation prediction model to obtain a predicted value of the roof separation amount, and the temporary support support pressure data is input into the hydraulic support bearing limit model to obtain a ratio of the current load of the support to the rated load.

[0082] When the predicted value of the roof separation amount exceeds the separation early warning threshold or the load ratio exceeds the bearing capacity early warning threshold, the safety risk level is output as high risk.

[0083] When the predicted value of the roof separation amount is within a first proximity range set by the separation early warning threshold and / or the load ratio is within a second proximity range set by the bearing capacity early warning threshold, the safety risk level is output as medium risk.

[0084] When the predicted value of the roof separation amount is lower than the separation early warning threshold and the load ratio is lower than the bearing capacity early warning threshold, the safety risk level is output as low risk.

[0085] The roof separation prediction model is a commonly used existing model for evaluating the stability of the roof in a coal mine, and the core function is to predict the development trend of the roof separation of the rock stratum in a future period of time based on the real-time collected displacement data of the rock stratum at the top of the support equipment. The input is the displacement data of the rock stratum at the top of the support equipment obtained by the environment perception module, and the output is the predicted value of the roof separation amount. The hydraulic support bearing limit model is a classical existing model for evaluating the load capacity of the support equipment, and is used to determine the matching degree between the actual bearing state of the temporary support bracket and the safety boundary. The input is the real-time pressure data of the temporary support bracket, and the ratio of the current load to the rated load is calculated by establishing a structure mechanics model of the hydraulic support, combined with preset conditions such as material strength parameters and rated load of the support design.

[0086] The mode arbitration unit is configured to arbitrate the working mode according to the safety risk level; when the safety risk level is high risk, the working mode is manually arbitrated; when the safety risk level is medium risk, the current working mode is maintained; and when the safety risk level is low risk, the working mode is automatically arbitrated.

[0087] The above-mentioned PLC main controller is the core of the temporary support control system of the coal mine, which realizes the pitch angle fitting of the adaptive time window, the federated Kalman filter fusion positioning, and the dynamic threshold three-level state evaluation through the posture adjustment analysis unit, and outputs the three-level risk level of the roof separation prediction and the hydraulic support bearing limit model of the prediction safety analysis unit, and switches the working mode (high risk manual, medium risk maintain current, low risk automatic) through the mode arbitration unit, thereby effectively improving the support posture precision, risk control ability and underground operation efficiency.

[0088] The support control module is configured to generate a driving signal for driving the support equipment based on the posture adjustment amount and / or response information of the oil cylinder control unit belonging to the working mode according to the working mode and the posture adjustment amount output by the PLC main controller, and the response information is information generated by responding to the operation instruction input by the external remote control device;

[0089] The support control module includes an oil cylinder automatic control unit and an oil cylinder manual control unit arranged in parallel;

[0090] In the automatic working mode, the PLC main controller sends a command to start the oil cylinder automatic control unit to the oil cylinder automatic control unit, so that the oil cylinder automatic control unit generates a driving signal based on the posture adjustment amount according to a preset program sequence;

[0091] In the manual working mode, the PLC main controller sends a command to start the oil cylinder manual control unit to the oil cylinder manual control unit, so that the oil cylinder manual control unit receives the response information and maps the response information into a driving signal.

[0092] In the specific implementation process, the support control module serves as the "executive brain" of the entire system, responsible for converting the abstract decisions of the PLC main controller into precise and executable driving signals to directly control the hydraulic cylinder action of the support equipment. The core design of this module adopts a dual-redundancy control architecture, i.e., the parallel arrangement of the cylinder automatic control unit and the cylinder manual control unit, ensuring reliable switching and absolute safety between efficient automation and emergency manual intervention.

[0093] In the automatic mode, when the PLC main controller issues an "automatic" command based on good working condition data, it sends a mode switching command to the support control module, activates the cylinder automatic control unit, and locks the cylinder manual control unit. The activated cylinder automatic control unit then takes over the system control. The cylinder automatic control unit works according to a preset program sequence, which includes: the cylinder automatic control unit analyzes the posture adjustment amount and converts it into the target extension amount of the specific cylinder, and sequentially sends pulse signals to the corresponding cylinder group to drive the gantry installation mechanical arm to accurately adjust the pitch angle and correct the lateral position; during the adjustment process, the cylinder automatic control unit reads the feedback data of the angle sensor and position encoder in real time and compares it with the target value until the error enters the allowable tolerance range, completing one step of adjustment.

[0094] In the manual mode, when the PLC main controller determines that the safety risk level is high, it triggers mode switching, activates the cylinder manual control unit, and puts the cylinder automatic control unit into standby state. At this time, the control of the system is handed over to the operator. The operator issues operation commands through physical buttons on the external remote control device. The core function of the cylinder manual control unit is "mapping": it receives and analyzes the command signals from the remote control device in real time, i.e., response information, and maps them one-to-one into driving signals for specific cylinders. For example, pressing the "No. 1 arm up" button on the remote control generates a driving signal to control the corresponding cylinder to extend and lift the mechanical arm. This design allows the operator to directly and flexibly respond to complex or unexpected working conditions based on field experience.

[0095] Further, the instructions issued by the mode arbitration unit have the highest priority, ensuring that only one of the two control circuits is activated at any time, fundamentally avoiding equipment malfunctions caused by command conflicts. In addition, regardless of the mode, the independent emergency stop signal has the highest global interrupt priority, which will immediately cut off the power supply to all cylinders to ensure personnel and equipment safety.

[0096] Further, the support control module further comprises a visual camera marking unit.

[0097] The visual camera marking unit comprises an industrial camera and an ArUcoMarker binary square marker, which are installed on the gantry installation mechanical arm in an upward direction;

[0098] The ArUcoMarker binary square marker is fixed below the center of the top beam of the temporary support support, and carries digital code information of the support;

[0099] The oil cylinder automatic control unit is in signal connection with the visual camera marking unit;

[0100] In the automatic working mode, the oil cylinder automatic control unit calls the visual camera marking unit to obtain the center point pose of the temporary support support by recognizing the ArUcoMarker binary square marker, and generates the centering adjustment data for accurate positioning; the centering adjustment data and the attitude adjustment amount are fused to generate a driving signal.

[0101] Specifically, after the automatic working mode is activated, the oil cylinder automatic control unit periodically calls the visual camera marking unit while moving the support according to the preset program. The working process is a typical machine vision positioning process: first, the industrial camera collects the image of the bottom of the top beam containing the marker; then, the four corner points and the unique ID code of the ArUcoMarker are detected and recognized in real time by using the built-in image processing algorithm; finally, based on the camera's intrinsic parameters (obtained by pre-calibration) and the actual physical size of the marker, the three-dimensional space coordinates and the rotation angle of the marker center point relative to the camera are accurately calculated by the perspective n-point positioning algorithm, that is, the center point pose of the temporary support support is obtained. Then, the oil cylinder automatic control unit obtains the centering adjustment data by calculating the deviation between the actual center point pose and the ideal center point pose of the support.

[0102] Subsequently, the oil cylinder automatic control unit performs weighted fusion on the attitude adjustment amount calculated based on the stability of the equipment and the centering adjustment data based on vision to generate the final driving signal. This set of signals can simultaneously command multiple oil cylinders to act in coordination, so that the gantry installation mechanical arm can accurately move the support to the specified position while maintaining its own stability, thereby completing the high-precision automatic installation work.

[0103] The support control module significantly improves the accuracy, adaptability and intrinsic safety level of support operation by constructing an intelligent execution system with automatic and manual dual-channel redundant control. In the automatic mode, the support control module can autonomously drive the mechanical arm to complete the accurate and efficient installation of the support based on the decision instruction of the PLC main controller and visual auxiliary positioning. In the manual mode, the direct control right of the operator in complex working conditions is ensured through intuitive instruction mapping. Most importantly, the module has strict mode interlocking and emergency stop priority mechanism, which fundamentally eliminates the risk of instruction conflict and system out-of-control, and realizes the unity of intelligent efficient operation and high reliability and safety protection.

[0104] The support structure is used to drive the support equipment to complete the pushing, positioning and installation operation of the temporary support support based on the driving signal.

[0105] The support structure includes a driving element and a limit protection element;

[0106] The driving element includes a motor and a hydraulic cylinder, and the support equipment includes a shed moving mechanism and a shed installation mechanical arm;

[0107] The motor is used to drive the shed moving mechanism to move the temporary support support as a whole to the designated operation position in the well; the hydraulic cylinder is provided with 6 groups of 12 cylinders, which are symmetrically distributed on both sides of the shed installation mechanical arm, and is used to drive the shed installation mechanical arm to perform accurate positioning and installation of the temporary support support;

[0108] Specifically, the motor as the core power source usually adopts an explosion-proof three-phase asynchronous motor to directly drive the shed moving mechanism, which is responsible for moving the temporary support support as a whole horizontally from the storage position to the designated operation position in the well; the hydraulic cylinder receives the driving signal from the support control module through an electro-hydraulic proportional valve or a servo valve, each group of cylinders performs precise coordination, and finally drives the shed installation mechanical arm to complete the millimeter-level accurate positioning of the support in the three-dimensional space and the stable installation with the roof and the side slope.

[0109] The limit protection element includes a first limit switch and a second limit switch, the first limit switch is installed at the starting point and the ending point of the shed moving mechanism driven by the motor, and the second limit switch is installed at the ending point of the extension stroke of each hydraulic cylinder.

[0110] The first limit switch is used to detect the extreme motion position of the shed moving mechanism: when the shed moving mechanism drives the temporary support support to reach the designated operation position in the well, the first limit switch is triggered and the motor stops running.

[0111] The second limit switch is used to detect the ending point of the extension stroke of the hydraulic cylinder: when the hydraulic cylinder drives the shed installation mechanical arm to move to the designed installation position of the temporary support support, the second limit switch is triggered and the hydraulic cylinder stops moving.

[0112] Specifically, the first limit switch is a stroke limit switch installed at the starting point and the ending point of the shed frame pushing mechanism, which is a mechanical lever limit switch or a non-contact proximity switch. When the shed frame pushing mechanism moves to the starting point or the ending point, it will touch the lever or enter the sensing area, causing the contact state in the switch to change (from normally open to normally closed or vice versa), thereby sending a high-level signal to the PLC main controller. After receiving this signal, the PLC main controller will immediately cut off the power supply of the motor, making it stop running.

[0113] The second limit switch refers to a limit switch installed on or near each oil cylinder body, used to detect the limit position of the piston rod. For an oil cylinder, one is usually set at the maximum extension position and one at the maximum retraction position. The second limit switch uses an internal magnetostrictive displacement sensor or an external proximity switch. When the piston rod of the oil cylinder moves to the limit position, the corresponding limit switch will be triggered. This signal will be immediately fed back to the hydraulic control system, closing the reversing valve of the corresponding oil cylinder and cutting off the oil circuit, making the oil cylinder stop moving. This directly prevents "pressure build-up", internal damage or impact on the mechanical structure caused by excessive extension and retraction of the oil cylinder, and is the key to achieving precise positioning and hardware safety.

[0114] In summary, the driving element and the limit protection element together constitute a rigid-flexible execution system: the driving element is responsible for providing power and action, while the limit switch serves as an independent hardware safety barrier, providing the ultimate and most reliable safety guarantee for the automatic control process, ensuring that the entire support operation is carried out within the preset physical boundaries without any risk.

[0115] In some embodiments of the present application, the external remote control device is signal-connected with the oil cylinder manual control unit, and the external remote control device is provided with: physical buttons corresponding one-to-one to the forward and backward movements of each oil cylinder and an independent emergency stop button.

[0116] Further, the PLC-based coal mine temporary support control system of the present application further comprises a power supply module, a wireless communication module, an information display module, and a danger warning module.

[0117] Among them, referring to Figure 2 The output end of the power supply module is connected to the input end of the environment perception module, the output end of the environment perception module is connected to the input end of the wireless communication module, the output end of the wireless communication module is connected to the PLC main controller, the output end of the PLC main controller is connected to the input end of the support control module, the output end of the support control module is connected to the input end of the support structure, the output end of the support control module is connected to the input end of the information display module, and the input end of the information display module is connected to the input end of the danger warning module.

[0118] In the specific implementation process, the wireless communication module adopts RS485 bus communication mode, has superior anti-noise performance, and fast transmission rate. The inter-system communication of the system adopts RS-485 interface serial data communication mode, is designed as two-way communication mode, one way is responsible for information receiving, and the other way is responsible for information sending, which are independent of each other, avoiding information conflict, the optical coupling isolation chip is TLP521, and the MAX485 chip is used for level conversion.

[0119] In the embodiment of the application, the information display module programs the display interface of the system on the embedded version MCGS configuration development software. The display screen only supervises and displays the real-time state of each part of the system, and does not change the state and control. For example, the state of the PLC main controller is divided into three states of power-on, emergency stop and timeout. When the system is in the power-on state and normally runs, the real-time in-out oil states of the six oil cylinders on one side are displayed to represent that the corresponding oil cylinder is advancing, retreating or stopping, and the oil cylinder liquid level position is also displayed. When the motor drives the whole shed frame to move forward, it will be displayed in the form of motor advancing on the display screen.

[0120] The danger early warning module reads the readings of the multi-point displacement meter, analyzes the data of the hydraulic support, analyzes the data of the roof separation, and can also manually input the data monitored by the artificial monitoring. The corresponding early warning threshold is established, the related theoretical model is nested, the numerical calculation software is called for joint analysis, and when the dangerous factors break through the set threshold, the alarm program is started. The alarm reason can be found out, and corresponding measures can be taken. For example, when the roof separation, support overload, anchor rod failure, personnel entering the non-safety area and the like, when any factor breaks through the threshold, the sound and light alarm is started and the specific risk position is marked on the information display module.

[0121] The coal mine temporary support control system based on PLC provided by the application realizes comprehensive and accurate acquisition of working condition data through the cooperation of multiple sensors of the environment perception module and data mutual calibration, and provides reliable global data support for decision-making. The PLC main controller accurately generates attitude adjustment amount and three-level safety risk grade through adaptive time window fitting, federal Kalman filter fusion positioning and double model risk assessment, and realizes intelligent operation mode switching in combination with mode arbitration. The support control module adopts double-redundancy control architecture and visual auxiliary positioning, and is matched with the limit protection element of the support structure, so as to ensure accurate execution and hardware safety of operation. The anti-interference communication, state display and danger early warning module are supplemented, a closed loop of “perception-decision-execution-protection” is formed, the support attitude precision, risk control ability and underground operation efficiency are effectively improved, the operation essential safety is strengthened through mode interlocking and emergency stop priority mechanism, and the complex and changeable operation environment in the coal mine is adapted.

[0122] In the description of the application, it should be understood that the terms "first", "second" are used only for descriptive purposes, and cannot be construed as indicating or implying relative importance or implying the number of the technical features indicated. Therefore, the features defined as "first", "second" can be explicitly or implicitly included one or more of the features. In the description of the application, the meaning of "a plurality of" is two or more, unless otherwise explicitly specified and limited.

[0123] In this application, unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting", "fixing" and the like should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrated; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0124] In this application, unless otherwise explicitly specified and limited, the first feature is "on" or "under" the second feature, which can be direct contact between the first and second features, or indirect contact between the first and second features through intermediate medium. Moreover, the first feature is "on", "above" and "above" the second feature, which can be directly above or obliquely above the first feature, or only indicates that the first feature is higher than the second feature in horizontal height. The first feature is "under", "below" and "below" the second feature, which can be directly below or obliquely below the first feature, or only indicates that the first feature is lower than the second feature in horizontal height.

[0125] In the description of the application, the description of the terms "one embodiment", "some embodiments", "embodiment", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the application. In this specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples, without contradiction.

[0126] Although the embodiments of the application have been shown and described above, it should be understood that the above embodiments are exemplary and cannot be construed as limiting the application, and those skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the application.

Claims

1. A PLC-based temporary support control system for coal mines, characterized in that, include: The environmental sensing module is located underground in the coal mine and acquires real-time environmental condition data when the support equipment is in operation. The PLC main controller is used to analyze the working condition data to obtain the attitude adjustment amount and safety risk level of the current support equipment operation, and to determine the working mode of the support control module of the support equipment based on the safety risk level. The support control module is used to generate a drive signal for the support equipment based on the working mode and attitude adjustment amount output by the PLC main controller, so that the hydraulic cylinder control unit to which the working mode belongs generates the drive signal based on the attitude adjustment amount and / or response information. The response information is information generated in response to the operation command input by the external remote control device. The support structure is used to drive the support equipment to complete the pushing, positioning and installation of the temporary support bracket based on the drive signal.

2. The PLC-based temporary support control system for coal mines according to claim 1, characterized in that, The environment sensing module includes: Vision sensors, ultrasonic sensors, pressure sensors, angle sensors, encoders, and LiDAR; The environmental perception module collects working condition data including the real-time position, real-time pitch angle, and direction of travel of the support equipment; the anchor bolt position and center point of the temporary support frame; obstacle information; displacement data of the top rock layer of the support equipment; and pressure data of the temporary support frame.

3. The PLC-based temporary support control system for coal mines according to claim 2, characterized in that, The PLC main controller includes: The attitude adjustment analysis unit is used to compare and analyze the real-time pitch angle and travel direction of the support equipment with the historical movement trajectory, obtain the slope of attitude change and the lateral offset, and generate attitude adjustment amount based on the slope of attitude change and the lateral offset. The predictive safety analysis unit is used to analyze the displacement data of the top rock layer and the pressure data of the temporary support frame based on the top plate delamination prediction model and the hydraulic support bearing limit model to obtain the safety risk level. The mode arbitration unit is used to arbitrate the working mode according to the security risk level; when the security risk level is high, the arbitration is manual working mode; when the security risk level is medium, the arbitration is to maintain the current working mode; when the security risk level is low, the arbitration is automatic working mode.

4. The PLC-based temporary support control system for coal mines according to claim 3, characterized in that, The attitude adjustment analysis unit is specifically used for: Within a set time window, the real-time pitch angle data collected by the angle sensor and encoder are linearly fitted, and the slope of the fitted straight line is used as the pitch angle change rate to characterize the dynamic change trend of the equipment's pitch attitude. By fusing real-time position data from encoders and lidar, the vertical distance from the current position of the support equipment to the preset ideal trajectory fitted from historical motion trajectories is obtained, which is used as the lateral offset. The pitch angle change rate and lateral offset are compared with dynamic thresholds established based on historical data, and the attitude adjustment amount is generated based on the comparison results.

5. The PLC-based temporary support control system for coal mines according to claim 3, characterized in that, The predictive security analysis unit is specifically used for: The displacement data of the roof strata is input into the roof delamination prediction model to obtain the predicted value of the roof delamination amount; the pressure data of the temporary support is input into the hydraulic support bearing limit model to obtain the ratio of the current load of the support to the rated load. When the predicted value of the top slab delamination exceeds the delamination warning threshold, or the load ratio exceeds the bearing capacity warning threshold, the safety risk level is output as high risk. When the predicted value of the top plate delamination amount does not exceed the delamination warning threshold but is within the first adjacent range set by the delamination warning threshold, and / or the load ratio does not exceed the bearing capacity warning threshold but is within the second adjacent range set by the bearing capacity warning threshold, the output safety risk level is medium risk. When the predicted value of the top plate delamination is lower than the delamination warning threshold and the load ratio is lower than the bearing capacity warning threshold, the output safety risk level is low risk.

6. The PLC-based temporary support control system for coal mines according to claim 1, characterized in that, The support control module includes a hydraulic cylinder automatic control unit and a hydraulic cylinder manual control unit arranged in parallel. In automatic operation mode, the PLC main controller sends a command to start the hydraulic cylinder automatic control unit to the hydraulic cylinder automatic control unit, so that the hydraulic cylinder automatic control unit generates a drive signal according to a preset program sequence based on the attitude adjustment amount; In manual operation mode, the PLC main controller sends a command to start the manual control unit of the hydraulic cylinder to the manual control unit of the hydraulic cylinder, so that the manual control unit of the hydraulic cylinder receives the response information and maps the response information into a drive signal.

7. The PLC-based temporary support control system for coal mines according to claim 6, characterized in that, The support control module also includes: a visual camera marking unit; The visual camera marking unit includes an industrial camera mounted on a scaffold-mounted robotic arm and an ArUcoMarker binary square marker. The ArUcoMarker binary square marker is fixed below the center of the top beam of the temporary support frame, and the ArUcoMarker binary square marker carries the digital code information of the support frame. The automatic control unit of the hydraulic cylinder is signal-connected to the visual camera marking unit; In the automatic working mode, the hydraulic cylinder automatic control unit calls the vision camera marking unit to obtain the center point pose of the temporary support bracket by recognizing ArUcoMarker binary square markers, and generates centering adjustment data for precise positioning; the centering adjustment data is fused with the attitude adjustment amount to generate a drive signal.

8. The PLC-based temporary support control system for coal mines according to claim 1, characterized in that, The support structure includes a driving element and a limiting and protective element; The driving element includes a motor and a hydraulic cylinder, and the support equipment includes a canopy pushing mechanism and a canopy installation robotic arm. The motor is used to drive the canopy pushing mechanism to move the temporary support support as a whole to the designated working position downhole; there are a total of 6 groups of 12 hydraulic cylinders, symmetrically distributed on both sides of the canopy installation robotic arm, used to drive the canopy installation robotic arm to perform precise positioning and installation of the temporary support support; The limit protection element includes a first limit switch and a second limit switch. The first limit switch is installed at the start and end points of the motor-driven scaffolding pushing mechanism, and the second limit switch is installed at the end point of the extension and retraction stroke of each cylinder.

9. The PLC-based temporary support control system for coal mines according to claim 6, characterized in that, The first limit switch is used to detect the extreme movement position of the canopy pushing mechanism: when the canopy pushing mechanism drives the temporary support to the designated working position downhole, the first limit switch is triggered and the motor stops running; The second limit switch is used to detect the end point of the extension and retraction stroke of the hydraulic cylinder: when the hydraulic cylinder drives the scaffolding installation robot arm to move to the designed installation position of the temporary support bracket, the second limit switch is triggered and the hydraulic cylinder stops moving.

10. The PLC-based temporary support control system for coal mines according to claim 6, characterized in that, The external remote control device is connected to the manual control unit of the hydraulic cylinder. The external remote control device is equipped with physical buttons corresponding to the forward and backward movements of each hydraulic cylinder, as well as an independent emergency stop button.

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