Method for protecting the soft leg of a side crane

Abstract

The application discloses a soft leg protection method of a side crane, and belongs to the technical field of crane outriggers, and comprises the following steps: abnormal detection of electrical equipment startup, entry level exception bottoming; startup initialization and history state recovery; scene judgment, adaptation to different operation stages; soft leg state detection of multi-dimensional sensor fusion; signal anti-shake and false trigger protection, avoiding soft leg misjudgment caused by industrial site vibration and electromagnetic interference. The application solves the technical problems of single soft leg judgment logic, poor adaptability, single sensor detection, low reliability, poor fault tolerance, protection failure caused by soft leg misjudgment in the early stage of startup and history state loss, and imperfect abnormal processing without full-process bottoming. The application can accurately identify the soft leg in the early stage (i.e. when the supporting force starts to abnormally decrease but the structure has not obviously tilted) and immediately take protection measures, thereby providing essential technical support for the safe operation of the side crane.

Description

Technical Field

[0001] This invention belongs to the field of crane outrigger technology and relates to a method for protecting the soft legs of a side-mounted crane. Background Technology

[0002] Currently, side-mounted cranes are core handling equipment in ports, shipyards, large equipment manufacturing workshops, and heavy equipment installation sites. Their key feature is that one or both outriggers run along fixed tracks. During the operation of lifting containers (or container-like containers) from the ground onto vehicles, the direction of force changes, shifting the force on the entire vehicle to the opposite side of the outrigger support. This causes a decrease or even loss of support force on the outrigger side, leading to the "soft leg" phenomenon. A soft leg exacerbates lateral swaying and shaking of the upper vehicle, significantly reduces lifting accuracy, and subjects critical structural components such as the boom to additional lateral forces, accelerating their wear, fatigue cracking, and even damage. Simultaneously, it weakens the overall lateral stability of the vehicle, increasing the risk of cargo falling and boom scraping, and in severe cases, can cause the entire vehicle to overturn.

[0003] Currently, there are few solutions for soft leg protection for side-mounted cranes in the industry. Common methods include detection using a single tilt sensor or protection based on a single leg pressure (or load) sensor. Single-type sensors are susceptible to interference from industrial vibrations and environmental factors, which can lead to distorted detection data, false or missed detections of soft legs, and problems such as delayed response and poor anti-interference capabilities.

[0004] Among existing related patent technologies, Chinese patent (patent number: CN202210897654.3) collects support pressure data in real time through a pressure sensor at the bottom of the outrigger cylinder, compares it with a preset threshold to determine a "soft leg," triggers an alarm, and prohibits operation. It also incorporates filtering to reduce on-site interference. Chinese patent (patent number: CN202011432567.8) combines outrigger extension data from a displacement sensor and outrigger tilt data from a tilt sensor to calculate the actual support state of the outrigger. If the data exceeds a safety threshold, a soft leg is determined, and an early warning is issued. It can control the outrigger cylinder to compensate for pressure and includes a manual reset function. Chinese patent (patent number: CN202122845638.9) uses a mechanical limit switch in conjunction with a pressure sensor to detect the outrigger's extended position and support pressure. If the outrigger is not fully extended or the pressure is insufficient, a soft leg is determined, the hoisting and luffing circuits are cut off to prohibit dangerous operation, and an alarm is triggered simultaneously.

[0005] However, the existing solutions have three major limitations: 1. Insufficient adaptability of judgment logic to different operating conditions: Both CN202210897654.3 and CN202011432567.8 adopt a "single fixed threshold comparison" judgment logic, without setting differentiated rules based on different stages of crane standby adjustment and operation. In standby mode, a single threshold limits the flexibility of outrigger adjustment and cannot adapt to special operating conditions such as uneven ground; in operating mode, a single parameter comparison is difficult to accurately identify the slight displacement of the outriggers that are precursors to outrigger slippage, which easily leads to missed judgments and cannot dynamically adapt to the state after outrigger adjustment, resulting in a high false judgment rate.

[0006] 2. Insufficient reliability and fault tolerance: None of the solutions achieve deep fusion of multi-dimensional sensors, nor do they include adaptation logic for sensor failures. Single or limited types of sensors are susceptible to data distortion due to field vibrations, electromagnetic interference, temperature, humidity, dust, etc. There are no effective fallback detection methods for sensor failures, and there is a lack of a redundant supplementary mechanism for manual confirmation. This makes it impossible to cope with scenarios such as sensor jamming and special operating conditions, resulting in insufficient reliability and fault tolerance.

[0007] 3. Lack of end-to-end anomaly control: The existing solution's anomaly handling is limited to alarms and work prohibition after data exceeds limits, failing to integrate anomaly handling throughout the entire soft leg protection process and lacking entry-level and process-level anomaly fallback logic. Specifically, this manifests as: failure to detect sensor interface initialization anomalies; even when sensors are not connected or malfunctioning, the program may still use invalid data for judgment, leading to missed soft leg detections; failure to promptly terminate invalid logic execution when anomalies occur, resulting in delayed response that exacerbates accident risks; and the lack of anomaly data saving and fault location prompts, hindering operators from quickly troubleshooting problems and prolonging downtime. Summary of the Invention

[0008] Purpose of the invention: The purpose of this invention is to provide a method for protecting the soft legs of a side crane that is cost-controllable, responsive, accurate in judgment, and highly adaptive, and can accurately identify and immediately take protective measures in the early stage of "soft leg" occurrence (i.e. when the support force begins to decline abnormally but the structure has not yet tilted significantly), thereby providing essential technical protection for the safe operation of the side crane.

[0009] The technical solution of the present invention is: a method for protecting the soft legs of a side-mounted crane, comprising the following steps: Step (1) Detect abnormalities during the startup of electrical equipment and perform fallback measures for entry-level abnormalities; Step (2) Power-on initialization and restoration of historical state; Step (3) Analyze different scenarios and adapt to different work stages; Step (4) Detection of soft leg state by multi-dimensional sensor fusion; Step (5) Signal anti-shake and false trigger protection to avoid false judgment caused by industrial site vibration and electromagnetic interference.

[0010] Furthermore, the specific operation process of step (1) is as follows: after the controller device is powered on, it sends a start command according to the node number assigned to each sensor, establishes communication with each sensor, and determines whether each sensor interface has completed initialization.

[0011] Furthermore, if any interface is not initialized, the subsequent logic execution will be terminated, it will be judged as a "soft leg" and the operation will be prohibited to prevent invalid data from entering the soft leg judgment stage and eliminate the false leg caused by anomalies from the root. At the same time, an audible and visual alarm will be triggered to clearly indicate the sensor interface abnormality, so that operators can quickly locate the problem and simplify the abnormality handling operation.

[0012] Furthermore, the start command is sent using the CAN bus based on the node number assigned to each sensor.

[0013] Furthermore, the specific operation process of step (2) is as follows: First, a power-on delay stabilization mechanism is established. A delay function block is used to set a 2-second power-on delay. After the analog sensor completes initialization and the data stabilizes, the soft leg judgment logic is entered to avoid false judgment of soft leg. Next is the historical state recovery mechanism. By using the saved outrigger support position identifier, the outrigger status at the last shutdown is read. After the power-on initialization is completed, if the status is that the outrigger is in position, the real-time outrigger value is automatically assigned to the reference value to restore the historical reference value and avoid false judgment of soft leg. At the same time, the historical state data and reference value recovery record are dynamically saved, eliminating the need for operators to reconfirm the outrigger status and manually reset the reference value, simplifying the power-on operation and improving the convenience of operation. Finally, by using an initial identifier, we ensure that the power-on initialization logic is executed only once, avoiding the confusion of baseline values ​​and the disorder of the soft leg judgment logic caused by repeated initialization.

[0014] Furthermore, the specific operation process of step (3) is as follows: after confirming that all sensors are properly connected and initialized in steps (1) and (2), the program determines whether the crane is in standby or working state based on the boom status; if the booms of the front and rear cranes are both in the initial position, the crane is determined to be in standby state, at which time the outriggers are movable, and the outriggers are operated to effectively support the ground.

[0015] Furthermore, during this process, the real-time values ​​of the outriggers are assigned to the reference values ​​to ensure that the reference values ​​are synchronized with the outrigger adjustment status. When the outriggers are back in place, the reference values ​​are automatically refreshed to avoid misjudgment of soft legs. At the same time, the data of each reference value update is dynamically saved to the system storage module. If either the boom of the front or rear crane is not in its initial position, the crane is determined to be in operation. The real-time extension length and luffing angle values ​​of the outriggers obtained by the sensors are compared with the saved reference values. Only when all deviations are less than or equal to the corresponding allowable deviation values ​​is it determined that the outriggers are not soft. If any parameter deviation exceeds the standard, it is determined to be a soft leg, and a prohibition signal is output, while triggering the personnel protection interlock.

[0016] Furthermore, the boom status specifically refers to: obtaining the tilt angle value through sensors to determine whether the boom has been lowered into position; The standby state is adapted to the initial operation scenario; The described work status is adapted to scenarios where there is a temporary power outage during the work process; The initial position is one that simultaneously satisfies the following conditions: the lower boom of the front crane is in the luffing position, the upper boom of the front crane is in the luffing position, the lower boom of the rear crane is in the luffing position, and the upper boom of the rear crane is in the luffing position. The allowable deviation values ​​are: outrigger extension length ±50mm and outrigger luffing angle ±2°.

[0017] Furthermore, the specific operation process of step (4) is divided into three aspects: First, the analog sensor provides real-time detection. Through the sensor interface, it synchronously reads the real-time values ​​of the included angle and length of the front and rear outriggers, as well as the sensor status and fault signs, covering all key parameters of the outriggers. This enables accurate quantitative detection of the outrigger support status and provides core data for determining the outriggers' weakness. Second, physical limit sensor hardware protection, through the compaction detection proximity switch, detects whether the outrigger is fully extended and supported in place, forming a hardware backup for soft leg protection, avoiding false leg detection; Third, manual confirmation signal redundancy supplementation is provided by setting a manual selection signal as a supplement to sensor detection. This is adapted to the situation when loading and unloading containers for accompanying vehicles, where the rear crane outriggers are supported on the ground behind the accompanying vehicle and the front crane outriggers are supported on the vehicle frame. At the same time, it can also deal with special working conditions such as physical limit switch jamming and uneven ground. Operators can manually confirm that the outriggers are in place to avoid misjudgment due to weak legs.

[0018] Furthermore, step (5) specifically involves: to ensure the accuracy of weak leg determination, based on the multi-dimensional weak leg detection in step (4), signal anti-shake and false trigger protection functions are implemented; First, signal anti-shake processing is performed by using step detection to capture the rising and falling edges of boom position signals, manual selection signals, and sensor position signals, so as to avoid instantaneous signal fluctuations caused by field vibrations and electromagnetic interference, and prevent the soft leg judgment logic from switching repeatedly. Next, false trigger protection is implemented. The signal is manually selected to capture the rising edge through the step detection function to ensure that manual confirmation only takes effect on the first press, avoiding repeated sensor triggering and false judgment caused by the operator continuously pressing the button. At the same time, manually selecting the activation method satisfies the dual prerequisites of normal sensor operation and compliant outrigger parameters, thus preventing misjudgments of weak legs caused by manual operation errors.

[0019] The technical problem solved by this invention is as follows: I. Solving the technical problem of "single soft leg judgment logic and poor adaptability": The present invention provides a scenario-based soft leg judgment method, which divides the standby state and the working state according to whether the boom is in the initial position, and adopts differentiated judgment logic (dual judgment in the standby state and deviation comparison in the working state) to realize dynamic updating of the benchmark value, adapt to the needs of different working stages, and improve the accuracy and adaptability of soft leg judgment. II. Solving the technical problems of "single sensor detection, low reliability, and poor fault tolerance": This invention adopts multi-dimensional sensor fusion detection technology, which integrates analog sensors, physical limit sensors, and manual confirmation signals to form triple redundancy detection; it monitors the sensor status in real time, automatically disables related functions when a sensor fails, forces the use of reliable detection methods, improves the reliability and fault tolerance of detection, and copes with interference and sensor failure scenarios in complex industrial sites. III. Solving the technical problem of "false judgment of soft leg in the early stage of power-on and protection failure caused by loss of historical status": This invention establishes a complete power-on initialization logic to achieve stable sensor data and restoration of historical status, prevent false judgment of soft leg in the early stage of power-on from the source, and realize the dynamic storage of initialization data and historical status data, simplifying the power-on operation and taking into account personnel protection and ease of operation. IV. Solving the technical problems of "imperfect anomaly handling and lack of full-process fallback": This invention establishes an anomaly-priority full-process fallback logic. At the entry point, sensor interface anomalies are detected first. During the process, various anomaly scenarios are adapted in real time. In anomaly state, a soft leg signal is forcibly output to terminate invalid logic execution, trigger safety interlocks and alarms, and provide clear fault prompts, thereby improving the timeliness and reliability of anomaly handling and preventing the accident from escalating.

[0020] Beneficial Effects: Compared with existing technologies, this invention has the following significant advantages: 1. Significantly improves the accuracy and scenario adaptability of soft leg detection. By employing scenario-differentiated detection logic combined with dynamic updating of benchmark values, it effectively solves the problems of false and missed detections of soft legs in existing technologies, achieving early warning of soft legs and greatly improving the adaptability of soft leg protection under complex working conditions; 2. Significantly improves the reliability and fault tolerance of soft leg detection. Through multi-sensor fusion to form triple redundant detection, it adapts to sensor failure scenarios in real time, avoiding protection failure caused by interference or failure of a single sensor, and significantly reducing the risk of missed soft leg detection; 3. Significantly improves the speed of anomaly response and the comprehensiveness of protection. Following the anomaly priority principle, it constructs a full-process fallback logic, quickly responding to various anomalies and triggering safety interlocks, eliminating safety hazards under abnormal conditions, and ensuring no blind spots in soft leg protection; 4. Significantly improves the level of operational automation. It automates the entire process from initial startup and soft leg detection to anomaly handling, significantly reducing manual operation steps, effectively reducing the workload of operators, and improving work efficiency; 5. It significantly reduces the incidence of soft leg-related safety accidents, effectively avoids accidents such as equipment overturning and personal injury, greatly reduces economic losses such as equipment maintenance, personnel rescue, and downtime, and lowers the safety costs of enterprises. Attached Figure Description

[0021] Figure 1 This is a flowchart of the present invention; Figure 2 This is a schematic diagram of the side crane in this invention (in the figure: 1. Tractor, 2. Hydraulic tank assembly, 3. Hydraulic system, 4. Front lifting device, 5. Electrical control system, 6. Semi-trailer, 7. Rear lifting device, 8. Sliding cylinder; this figure is only used to show the structure of the side crane). Figure 3 This is a schematic diagram of the front lifting device of the side crane in this invention (the rear lifting device is symmetrical to the front lifting device and includes: 1. lifting device, 2. upper boom structure, 3. upper boom cylinder, 4. lower boom structure, 5. outrigger telescopic cylinder, 6. outrigger structure, 7. outrigger luffing cylinder, 8. lower boom cylinder, 9. valve frame, 10. base, 11. outrigger; the soft leg protection method proposed in this invention corresponds to the outrigger shown in this diagram). Figure 4 This is a schematic diagram showing the positions of the compaction detection switch, long angle sensor, and horizontal tilt sensor of the present invention (including: 1. Length angle sensor: used to detect the outrigger extension length and luffing angle in real time; 2. Single-axis tilt sensor: used to detect the upper arm luffing angle and lower arm luffing angle in real time; 3. Pressure sensor: used to detect the pressure values ​​of the upper arm luffing cylinder and lower arm luffing cylinder in real time; 4. Compaction detection proximity switch: used to detect the outrigger compaction status in real time; 5. Dual-axis tilt sensor: used to detect the horizontal angle of the base in real time). Detailed Implementation

[0022] The specific technical solution of the present invention will be further described in detail below with reference to specific examples.

[0023] As shown in the figure, this invention provides a method for protecting the soft legs of a lifting device mounted on a side-mounted crane. The program used in this method is written in ST (Structured Text) language on the CODESYS platform, and will not be described in detail hereafter. Figures 2-3 As shown, when loading containers (or similar containers), the vehicle must be parked next to the container (or similar container), with the container (or similar container) located on the side where the outriggers extend. The distance between the edge of the vehicle and the edge of the container (or similar container) should be 0.2m to 0.5m, and the vehicle and the container (or similar container) should be kept as parallel as possible. In the length direction of the vehicle, the container should be completely inside the booms of the front and rear lifting devices, and preferably in the middle of the front and rear lifting devices, to facilitate the outriggers to extend and provide support, and to avoid collisions.

[0024] After the vehicle is parked, the parking brake should be applied immediately, the clutch should be engaged, and the gear shift lever should be placed in neutral. Start the car, turn on the power take-off switch, and then slowly release the clutch pedal. At this point, the power take-off is in working condition. After checking that there is no obvious physical damage to the electrical components, power on the electrical equipment and operate it stably before operating the crane.

[0025] After ensuring the vehicle is properly positioned, confirm that the positions of the front and rear cranes are compatible with the container (or container-like object) to be lifted; first, use the remote control to fully extend the outriggers, then operate the outriggers to swing and adjust their amplitude until the outrigger plates are effectively supported on the ground. Once both the front and rear lifting outriggers are effectively supported (at this point, according to...), Figure 4 The compaction detection proximity switch determines whether the outriggers are not compacted (the indicator light on the detection switch will illuminate). At this time, the program will refresh and save the extension length and luffing angle of the outriggers of the front and rear cranes in real time (via...). Figure 4 (The length and angle are acquired by the sensor in the middle), and the remote control can operate the boom.

[0026] When space is limited, the telescopic outriggers cannot be fully extended, and the outrigger span cannot reach its maximum. After the outriggers touch the ground, the outrigger positioning detection switch may not trigger, requiring manual judgment and confirmation of the outrigger support status. At this time, the lateral tilt angle of the vehicle body caused by the outriggers supporting the ground should not exceed 1° (by...). Figure 4 (The system uses a dual-axis tilt sensor to obtain the horizontal angle of the base); after manually determining that the outriggers are in place, press the outrigger confirmation button to confirm; then the remote control can be used to operate the boom.

[0027] like Figure 1 As shown, in this embodiment, the provided method for protecting the soft leg specifically includes the following steps: Step (1): Detect abnormalities during the startup of electrical equipment and perform fallback measures for entry-level anomalies. In step (1), after the controller device is powered on, it sends a start command (using CAN bus) according to the node number assigned to each sensor, establishes communication with each sensor, and determines whether the interface of each sensor has completed initialization. If any interface is not initialized (sensor not connected, malfunction), the subsequent logic execution will be terminated immediately, and the operation will be prohibited to prevent invalid data from entering the soft leg judgment stage and eliminate the false leg missed due to abnormality from the root cause; at the same time, an audible and visual alarm will be triggered to clearly indicate "sensor interface abnormality", so that operators can quickly locate the problem and simplify the abnormality handling operation. Step (2), Power-on initialization and restoration of historical state: First, a power-on delay stabilization mechanism is established. A delay function block is used to set a 2-second power-on delay. After the analog sensor completes initialization and the data stabilizes, the soft leg judgment logic is entered to avoid false judgments caused by sensor data fluctuations in the early stage of power-on. Next is the historical state recovery mechanism. By saving the outrigger support position identifier, the outrigger status at the last shutdown is read. After the power-on initialization is completed, if the status is outrigger in position, the real-time outrigger value is automatically assigned to the reference value to restore the historical reference value and avoid false judgment of soft leg due to empty reference value after power-on. At the same time, historical status data and baseline value recovery records are dynamically saved, eliminating the need for operators to reconfirm the outrigger status or manually reset the baseline value. This greatly simplifies the power-on process, improves operational convenience, avoids the risk of outrigger failure due to operator error, and ensures personnel safety. Finally, by using an initial identifier, we ensure that the power-on initialization logic is executed only once, avoiding the confusion of baseline values ​​and the disorder of the soft leg judgment logic caused by repeated initialization; Step (3): Scenario-based judgment to adapt to different work stages: After confirming that all sensors are properly connected and initialized in steps (1) and (2), the program will determine whether the current crane is in "standby state (adapted to initial operation and other scenarios)" or "operation state (adapted to temporary power outage and other scenarios)" based on the boom status (the tilt angle value is obtained through the sensor to determine whether the boom has been lowered into position). If the booms of the front and rear cranes are both in the initial position (i.e., the lower boom of the front crane, the upper boom of the front crane, the lower boom of the rear crane, and the upper boom of the rear crane are all in the same position at the same time), the crane is determined to be in standby state. At this time, the outriggers are movable and can be operated to effectively support the ground. During this process, the real-time values ​​of the outriggers are assigned to the reference values ​​to ensure that the reference values ​​are synchronized with the outrigger adjustment status. When the outriggers are back in place, the reference values ​​are automatically refreshed to avoid misjudgment of soft legs caused by outrigger readjustment. At the same time, each reference value update data is dynamically saved to the system storage module. If either the boom of the front or rear crane is not in the initial position, the crane is determined to be in operation. At this time, the real-time extension length and luffing angle values ​​of the outriggers obtained by the sensors are compared with the saved reference values. Only when all deviations are ≤ the corresponding allowable deviation values ​​(outrigger extension length ±50mm, outrigger luffing angle ±2°) is it determined that there is no soft leg. If any parameter deviation exceeds the standard, it is determined to be a soft leg, and a prohibition signal is output. At the same time, the personnel protection interlock is triggered (stop boom movement and issue audible and visual alarms) to ensure the personal safety of the operators. Step (4), Detection of soft leg state by multi-dimensional sensor fusion: This step is carried out throughout the entire crane operation process, monitoring the status of the outriggers throughout the process to ensure that the outriggers are properly supported and to ensure operational safety. Its outrigger status monitoring is mainly divided into three aspects: First, real-time detection by analog sensors. Through the sensor interface, the angle and length of the front and rear outriggers are read synchronously, along with the sensor status and fault signs, covering all key parameters of the outriggers. This enables accurate quantitative detection of the outrigger support status and provides core data for outrigger determination. Second, physical limit sensor hardware protection, through the compaction detection proximity switch, directly detects whether the outrigger is fully extended and supported in place, forming a hardware backup for soft leg protection, avoiding false detection of soft leg due to analog sensor failure. Third, manual confirmation signal redundancy supplementation is provided by setting a manual selection signal as a supplement to sensor detection. This is adapted to the working conditions when loading and unloading of accompanying vehicle containers (or container-like containers), where the rear crane outriggers are supported on the ground behind the accompanying vehicle and the front crane outriggers are supported on the vehicle frame. At the same time, in special working conditions such as physical limit switch jamming or uneven ground, the operator can manually confirm that the outriggers are supported in place to avoid false judgments of soft legs due to sensor detection deviation. Step (5) Signal stabilization and false trigger protection to avoid false judgments caused by industrial vibrations and electromagnetic interference: In order to ensure the accuracy of weak leg detection, based on the multi-dimensional weak leg detection in step (4), step (5) mainly performs signal anti-shake and false trigger protection functions; First, signal anti-shake processing is performed using step detection to capture the rising and falling edges of boom position signals, manual selection signals, and sensor position signals. This avoids instantaneous signal fluctuations caused by field vibrations and electromagnetic interference, and prevents repeated switching of the soft leg judgment logic (such as scene misjudgment caused by boom position signal jitter, and sensor false triggering caused by manual selection signal jitter). Then, false trigger protection is implemented. The signal is manually selected to capture the rising edge through the step detection function to ensure that manual confirmation only takes effect on the "first press". This avoids repeated sensor triggering and false judgment caused by the operator continuously pressing the button. Meanwhile, manual selection requires both "normal sensor" and "outrigger parameters meeting standards" to be effective, further eliminating misjudgments of soft legs caused by manual operation errors, avoiding equipment tipping and personnel injuries caused by misoperation, and strengthening personnel protection.

[0028] Key technical points of this invention: (1) Scenario-based soft leg judgment technology based on boom position: It is one of the core logics of soft leg protection. Depending on whether the boom is in the initial position, a differentiated soft leg judgment logic is adopted. Through scenario division, the "flexibility of outrigger adjustment" and "operational safety" are taken into account. Manual intervention is allowed in the standby state to avoid misjudgment in special working conditions and reduce the difficulty of operation. In the working state, strict deviation comparison is adopted to accurately identify the small displacement of the outrigger (soft leg precursor) and realize early warning and protection of soft leg. (2) Multi-dimensional sensor fusion soft leg status detection technology: It integrates proximity switches and analog sensors, and is equipped with manual confirmation signals to form triple redundancy detection; through multi-dimensional fusion of "analog quantitative detection + physical hard limit + manual redundancy", it makes up for the limitations of a single sensor, realizes accurate detection of soft leg status, and at the same time copes with sensor failure scenarios, improving the reliability and fault tolerance of soft leg protection. (3) Soft leg safety interlock and fallback technology with anomaly priority: It integrates anomaly handling throughout the entire soft leg protection process, realizes the closed loop of "anomaly detection-safety interlock-program fallback", follows the "anomaly priority" principle of industrial control, and triggers safety interlock for any anomaly scenario that may lead to false judgment or missed judgment of soft leg, ensuring that there are no blind spots in soft leg protection and maximizing the safety of equipment and personnel; (4) Soft leg prevention technology for power-on initialization and historical state recovery: Through the perfect power-on initialization logic, it realizes sensor data stability and historical state recovery, prevents soft leg misjudgment in the early stage of power-on from the source, ensures the accuracy of soft leg judgment logic after power-on, and improves the continuity and reliability of soft leg protection. (5) Precision technology for weak leg judgment with signal anti-shake and false trigger protection: It achieves signal anti-shake through step detection and false trigger protection through logic limitation, ensuring the accuracy of the weak leg judgment signal and avoiding false judgment or missed judgment due to signal problems.

[0029] The points to be protected by this invention: (1) Scenario-specific soft leg judgment method: Based on whether the crane boom is in its initial position, the system divides the system into standby and working states, and adopts differentiated soft leg judgment logic. In the standby state, a dual judgment mode combining physical and virtual sensors is used to avoid misjudgment caused by a single sensor failure and improve the comprehensiveness of soft leg judgment. In the working state, a deviation comparison mode between the real-time value and the reference value of the outrigger parameters is adopted, and the reference value can be dynamically updated according to the outrigger status to achieve early warning of soft legs and avoid overturning accidents caused by the deterioration of soft legs. This method has strong adaptability, and the dynamic update mechanism of the reference value can be adapted to complex industrial scenarios such as outrigger adjustment, ground settlement, and load changes, avoiding false judgment of soft legs caused by outrigger readjustment, ensuring the reliability of soft leg protection under different working conditions, and eliminating the need for manual resetting of the reference value, thereby improving work efficiency. (2) Multi-sensor fusion method for soft leg status detection: The analog sensor, proximity switch and manual confirmation signal are fused to achieve triple redundancy detection of soft leg status; the analog sensor is used to read real-time quantitative data of the outrigger angle and length and the sensor status; the proximity switch is used to provide hardware feedback that the outrigger is in place; the manual confirmation signal is used to deal with special working conditions, and the manual confirmation function is automatically disabled when the sensor fails to ensure detection reliability; the sensor status is monitored in real time, and the manual confirmation function is automatically disabled when the sensor fails to force the use of a reliable detection method to avoid false judgment of soft leg based on invalid data; (3) Interlocking and fallback method prioritizing anomalies: Anomaly handling is integrated throughout the entire soft leg protection process. The program entry point prioritizes detecting sensor interface anomalies, and during the process, it adapts in real time to abnormal scenarios such as sensor failures and parameter deviations. In abnormal states, a soft leg signal is forcibly output to prohibit crane operation, and invalid logic execution is terminated, forming a closed loop of "anomaly detection - safety interlocking - program fallback". This method is suitable for complex anomaly scenarios in industrial sites (sensor failures, interface anomalies, parameter deviations), requires no manual intervention, and the program automatically completes anomaly handling and safety fallback, reducing the workload of operators and avoiding safety hazards caused by human error. (4) Power-on initialization and historical state recovery: When the power is on, the sensor data is stabilized through the delay function block, and the soft leg judgment logic is entered after the preset delay. At the same time, the historical state of the support leg when the power is off is read. If the historical state is that the support leg is in place, the support leg reference value is automatically restored to avoid false judgment of soft leg in the early stage of power-on. The initialization logic is executed only once to prevent the reference value from being confused. (5) Signal anti-jitter and false trigger protection: The step detection function block is used to capture the rising and falling edges of the relevant signals for soft leg determination to achieve signal anti-jitter; at the same time, the manual selection signal is logically restricted to ensure that manual confirmation is only effective under preset conditions, avoiding false judgment of soft leg caused by signal jitter and manual misoperation, improving the reliability of soft leg protection, adapting to the complex interference environment of industrial site, and ensuring long-term stable operation.

Claims

1. A method for protecting the soft legs of a side-mounted crane, characterized in that, Includes the following steps: Step (1) Detect abnormalities during the startup of electrical equipment and perform fallback measures for entry-level abnormalities; Step (2) Power-on initialization and restoration of historical state; Step (3) Analyze different scenarios and adapt to different work stages; Step (4) Detection of soft leg state by multi-dimensional sensor fusion; Step (5) Signal anti-shake and false trigger protection to avoid false judgment caused by industrial site vibration and electromagnetic interference.

2. The method for protecting the soft legs of a side-mounted crane according to claim 1, characterized in that, The specific operation process of step (1) is as follows: after the controller device is powered on, it sends a start command according to the node number assigned to each sensor, establishes communication with each sensor, and determines whether each sensor interface has completed initialization.

3. The method for protecting the soft legs of a side-mounted crane according to claim 2, characterized in that, If any interface is not initialized, the subsequent logic execution will be terminated, it will be judged as a "soft leg" and the operation will be prohibited to prevent invalid data from entering the soft leg judgment stage and eliminate the false leg missed due to anomalies from the root. At the same time, an audible and visual alarm will be triggered to clearly indicate the sensor interface abnormality, so that operators can quickly locate the problem and simplify the abnormality handling operation.

4. The method for protecting the soft legs of a side-mounted crane according to claim 2, characterized in that, The start command is sent using the CAN bus based on the node number assigned to each sensor.

5. The method for protecting the soft legs of a side-mounted crane according to claim 1, characterized in that, The specific operation process of step (2) is as follows: First, a power-on delay stabilization mechanism is established. A delay function block is used to set a 2-second power-on delay. After the analog sensor completes initialization and the data stabilizes, the soft leg judgment logic is entered to avoid false judgment of soft leg. Next is the historical state recovery mechanism. By using the saved outrigger support position identifier, the outrigger status at the last shutdown is read. After the power-on initialization is completed, if the status is that the outrigger is in position, the real-time outrigger value is automatically assigned to the reference value to restore the historical reference value and avoid false judgment of soft leg. At the same time, the historical state data and reference value recovery record are dynamically saved, eliminating the need for operators to reconfirm the outrigger status and manually reset the reference value, simplifying the power-on operation and improving the convenience of operation. Finally, by using an initial identifier, we ensure that the power-on initialization logic is executed only once, avoiding the confusion of baseline values ​​and the disorder of the soft leg judgment logic caused by repeated initialization.

6. The method for protecting the soft legs of a side-mounted crane according to claim 1, characterized in that, The specific operation process of step (3) is as follows: After confirming that all sensors are connected normally and initialized in steps (1) and (2), the program determines whether the crane is in standby or working state based on the boom status; if the booms of the front and rear cranes are both in the initial position, the crane is determined to be in standby state, at which time the outriggers can move and the outriggers are operated to effectively support the ground.

7. The method for protecting the soft legs of a side-mounted crane according to claim 6, characterized in that, During this process, the real-time values ​​of the outriggers are assigned to the reference values ​​to ensure that the reference values ​​are synchronized with the outrigger adjustment status. When the outriggers are back in place, the reference values ​​are automatically refreshed to avoid misjudgment of soft legs. At the same time, the data of each reference value update is dynamically saved to the system storage module. If either the boom of the front or rear crane is not in the initial position, the crane is determined to be in operation. The real-time extension length and luffing angle values ​​of the outriggers obtained by the sensors are compared with the saved reference values. Only when all deviations are less than or equal to the corresponding allowable deviation values ​​is it determined that the outriggers are not soft. If any parameter deviation exceeds the standard, it is determined to be a soft leg, and a prohibition signal is output, while triggering the personnel protection interlock.

8. The method for protecting the soft legs of a side-mounted crane according to claim 7, characterized in that, The boom status is specifically determined by obtaining the tilt angle value through sensors to determine whether the boom has been lowered into place. The standby state is adapted to the initial operation scenario; The described work status is adapted to scenarios where there is a temporary power outage during the work process; The initial position is one that simultaneously satisfies the following conditions: the lower boom of the front crane is in the luffing position, the upper boom of the front crane is in the luffing position, the lower boom of the rear crane is in the luffing position, and the upper boom of the rear crane is in the luffing position. The allowable deviation values ​​are: outrigger extension length ±50mm and outrigger luffing angle ±2°.

9. The method for protecting the soft legs of a side-mounted crane according to claim 1, characterized in that, The specific operation process of step (4) is divided into three aspects: First, the analog sensor provides real-time detection. Through the sensor interface, it synchronously reads the real-time values ​​of the included angle and length of the front and rear outriggers, as well as the sensor status and fault signs, covering all key parameters of the outriggers. This enables accurate quantitative detection of the outrigger support status and provides core data for determining the outriggers' weakness. Second, physical limit sensor hardware protection, through the compaction detection proximity switch, detects whether the outrigger is fully extended and supported in place, forming a hardware backup for soft leg protection, avoiding false leg detection; Third, manual confirmation signal redundancy supplementation is provided by setting a manual selection signal as a supplement to sensor detection. This is adapted to the situation when loading and unloading containers for accompanying vehicles, where the rear crane outriggers are supported on the ground behind the accompanying vehicle and the front crane outriggers are supported on the vehicle frame. At the same time, it can also deal with special working conditions such as physical limit switch jamming and uneven ground. Operators can manually confirm that the outriggers are in place to avoid misjudgment due to weak legs.

10. The method for protecting the soft legs of a side-mounted crane according to claim 1, characterized in that, The specific step (5) is: to ensure the accuracy of weak leg determination, on the basis of the multi-dimensional weak leg detection in step (4), the functions of signal anti-shake and false trigger protection are implemented; First, signal anti-shake processing is performed by using step detection to capture the rising and falling edges of boom position signals, manual selection signals, and sensor position signals, so as to avoid instantaneous signal fluctuations caused by field vibrations and electromagnetic interference, and prevent the soft leg judgment logic from switching repeatedly. Next, false trigger protection is implemented. The signal is manually selected to capture the rising edge through the step detection function to ensure that manual confirmation only takes effect on the first press, avoiding repeated sensor triggering and false judgment caused by the operator continuously pressing the button. At the same time, manually selecting the activation method satisfies the dual prerequisites of normal sensor operation and compliant outrigger parameters, thus preventing misjudgments of weak legs caused by manual operation errors.

Images