Intelligent judgment and hierarchical control method and system for over-amplitude alarm of overhead working truck

Abstract

The invention discloses an intelligent judgment and hierarchical control method and system for over-amplitude alarm of an overhead working truck, and relates to the technical field of overhead working safety control. The method comprises the following steps: firstly, dynamically maintaining a load reference value for representing a load state before an alarm; when an over-amplitude alarm occurs, whether the alarm is caused by the increase of the load is intelligently judged by comparing the increment of the current real-time load and the increment of the load reference value; if not, the boom is allowed to reset safely; if the load is increased, performing hierarchical control according to whether the real-time load exceeds a first safety load threshold value and a second safety load threshold value, and in the middle load interval, further judging whether the boom is allowed to act safely according to whether the operation amplitude exceeds the limit and whether the over-amplitude value meets the safety condition based on the load proportion. According to the invention, accurate distinguishing of alarm reasons and quantitative safety fault-tolerant control after overload are realized, and the operation continuity and safety are obviously improved on the premise of ensuring the stability of equipment.

Description

Technical Field

[0001] This invention belongs to the field of high-altitude operation safety control technology, and in particular relates to an intelligent judgment and hierarchical control method and system for over-range alarm of high-altitude operation vehicles. Background Technology

[0002] The safety of aerial work platforms relies on their overreach control system, which limits the maximum working radius under different loads through preset "operating curves." Traditional control strategies employ a multi-level stepped model, pre-setting several discrete load ranges (e.g., 0~120kg, 120~260kg), each corresponding to a fixed maximum working boundary curve. During operation, the system monitors in real time; once the boom radius touches the curve boundary corresponding to the current load, it triggers a limit alarm and prohibits movement in more dangerous directions.

[0003] However, this traditional strategy faces two prominent and interrelated technical challenges in actual complex dynamic operations:

[0004] (1) Risk of immediate overturning caused by "sudden increase in actual load". A common working condition is: after the equipment extends to the far end in a light load state, it loads a heavy object in the air, causing the total load to jump to a higher range instantly. At this time, its working position has seriously exceeded the safe range allowed by the new load, triggering a "serious overload alarm". For this kind of real overload, if the boom is simply allowed to retract or change its amplitude in order to clear the alarm, any movement in the already critically stable state may directly cause dynamic instability of the whole machine or structural overload, resulting in an overturning accident. To avoid this risk, a conservative existing solution is: once it is determined that the actual load exceeds the maximum allowable value of the current working boundary curve, all actions are locked, and it can only be cleared by reducing the weight on site or by the operator pressing the "over-authority button". Although this solution avoids the risk of erroneous action, it brings new problems: it is impossible to distinguish the cause of overload, and the "over-authority" operation depends on the subjective judgment of the human, which itself constitutes a serious safety hazard.

[0005] (2) False alarms and work interruptions caused by "complex curve switching". For equipment with complex boom structures (such as hybrid booms), the working curve is not simple. Within the same load range, the maximum allowable amplitude will vary drastically with different luffing angles and slewing areas, forming a complex network of multiple curves with "amplitude abrupt change" switching points. When the equipment normally passes through these switching points, even if the load does not change, it will trigger an over-amplitude alarm instantly due to the "jump" in the allowable amplitude. This is a non-load-related "false over-amplitude". If the above-mentioned "overload lockout" strategy is also adopted for this, it will cause the equipment to be frequently and unreasonably interrupted in a completely safe state, which will greatly damage the construction efficiency. Although theoretically all switching points can be avoided by pre-programming, this method is complex, easy to overlook, and has low practicality for multi-condition equipment.

[0006] To enhance the intelligence and flexibility of aerial work, existing technologies have been improved. For example, patent document CN117303274A establishes a continuous functional relationship between load and working range, achieving a smooth and gradual transition of the working curve, thus optimizing the smoothness and range utilization of normal operations. Patent document CN118047336A detects the shape of the extension and retraction platform and dynamically selects a more suitable working curve to explore potential working space. However, these improvements in existing technologies all focus on optimizing the boundary control logic under the "normal working mode," aiming to make the equipment "work better and smoother."

[0007] However, existing technologies do not offer an effective solution for accurately diagnosing the root cause of a "severe overload alarm" (is it a genuine overload or a tactical switch?) and implementing a safe yet flexible tiered and differentiated control strategy accordingly after the alarm is suddenly triggered. Current technologies either take potentially risky "allow retraction" actions after the alarm or adopt a "one-size-fits-all" complete lock-up strategy relying on dangerous "unauthorized" operations. Neither can intelligently handle such sudden situations while ensuring absolute safety, leaving equipment either exposed to risks or subjected to unnecessary operational interruptions. Therefore, there is an urgent need for an innovative method that can intelligently identify the cause of the overload and implement refined safety control based on engineering safety standards. Summary of the Invention

[0008] To address the aforementioned deficiencies in existing technologies, the present invention aims to provide an intelligent discrimination and hierarchical control method and system for overload alarms of aerial work platforms. This system aims to solve the technical problems of existing technologies, which, when dealing with severe overload alarms, cannot intelligently distinguish the cause of the alarm (whether it is a real overload or a curve switching), and can only adopt a "one-size-fits-all" complete lock-up or rely on dangerous "unauthorized" operations, thereby causing the equipment to either be exposed to the risk of overturning or suffer unnecessary work interruptions.

[0009] This invention solves the above-mentioned technical problems through the following technical solution: an intelligent discrimination and hierarchical control method for over-range alarm of aerial work vehicles, comprising:

[0010] Maintain a dynamically updated load reference value; wherein the load reference value is used to characterize the load status of the aerial work platform before the over-amplitude alarm occurs;

[0011] When an overload alarm occurs, the real-time load value of the current work column is obtained. Based on whether the increment of the real-time load value relative to the load reference value exceeds a preset load change threshold, it is determined whether the overload alarm is caused by an increase in load.

[0012] If the over-amplitude alarm is caused by factors other than increased load, the boom is allowed to move in a safe direction to deactivate the alarm.

[0013] If the overload alarm is caused by an increase in load, the following hierarchical control steps are executed:

[0014] If the real-time load value does not exceed the first safe load threshold, the boom is allowed to move in a safe direction;

[0015] If the real-time load value exceeds the first safe load threshold but does not exceed the second safe load threshold, then first determine whether the current working range exceeds the preset safe working range corresponding to the real-time load value; if it does not exceed, then the boom is allowed to move in a safe direction and is prohibited from moving in a direction that increases the working range; if it exceeds, then further determine whether the exceeded range value meets the condition determined based on the ratio between the real-time load value and the second safe load threshold; if it meets the condition, then the boom is allowed to move in a safe direction; if it does not meet the condition, then the boom movement is prohibited.

[0016] If the real-time load value exceeds the second safe load threshold, boom movement is prohibited.

[0017] This invention dynamically maintains load reference values ​​and intelligently determines the cause of overload alarms accordingly. It can accurately distinguish between "false overloads" caused by non-loading factors such as work curve switching and true overloads caused by actual load increases. For determined non-loading overloads, the system allows the boom to safely reset, enabling the equipment to automatically and quickly escape from unsafe limiting states caused by its own posture changes. This effectively avoids unnecessary work interruptions caused by misjudgments in existing technologies, significantly improving work efficiency and equipment utilization under complex working conditions.

[0018] For real-world overload conditions, this invention abandons the crude control methods of existing technologies that may allow dangerous actions, replacing them with a strict, tiered safety control logic. This control logic implements differentiated management of equipment actions based on a comparison between real-time load and preset first and second safe load thresholds. Particularly in higher-risk ranges, it introduces a joint judgment of the operating range and load ratio, ensuring that any permitted actions remain within the safety margins of dynamic stability and structural strength. This completely eliminates the risk of dynamic instability or structural damage caused by improper operation under overload and excessive amplitude critical states at the control logic level, achieving inherent safety.

[0019] This invention completely replaces "unauthorized" operations that rely on operator subjective judgment with an objective engineering algorithm model. By quantifying the dynamic / static stability design standards of aerial work platforms into specific safe load thresholds and amplitude tolerance algorithms based on load ratios, the system can automatically make safety decisions based on real-time sensor data. This not only completely eliminates safety hazards caused by human error or misjudgment, but also makes equipment self-rescue (safe retraction) possible within strict safety boundaries, thereby achieving automated and precise safety management without human intervention.

[0020] The core principle of this invention, "Diagnosis Based on Load Changes," is a universal diagnostic strategy independent of specific operational curve morphology. It does not rely on pre-programming and exhaustive management of a massive number of specific curve switching points, but rather uses the monitoring of changes in the fundamental parameter of load to uniformly identify the source of risk. This unified control architecture greatly simplifies the design and implementation of complex aerial work platform control systems for multiple loads, multiple turning zones, and multiple boom postures, reducing software complexity and maintenance costs, while simultaneously improving the system's reliability and adaptability under different machine types and operating conditions.

[0021] Furthermore, the load reference value is dynamically updated through the following steps:

[0022] When the aerial work vehicle is in normal operation without triggering the over-amplitude alarm, in response to the valid output signal of the boom action, it continuously collects the real-time load value of the work column at a predetermined sampling period and stores the N most recently collected real-time load values ​​in a sliding window.

[0023] In response to the shutdown of the boom action output signal, the average value is calculated based on the N real-time load values ​​within the sliding window, and the average value is updated as the load reference value.

[0024] By dynamically sampling using a sliding window during normal, alarm-free operating cycles and only calculating and updating the load reference value when the operation stabilizes, this ensures that the load reference value represents the typical load of the equipment during safe and stable operation, effectively eliminating data contamination caused by sudden loading, instantaneous sensor fluctuations, or momentary state disturbances during alarms. This creates the prerequisite for accurately comparing real-time loads with historical benchmarks, fundamentally guaranteeing the reliability and accuracy of the core diagnostic logic of "distinguishing whether over-amplitude is caused by loading," and is the cornerstone for the safe and effective operation of the entire intelligent hierarchical control scheme.

[0025] Furthermore, the time required from the start of data collection to filling the sliding window is greater than the shortest time required for the aerial work platform vehicle to start moving from the boom and trigger the over-amplitude alarm.

[0026] By precisely co-designing the sampling timing and alarm triggering timing, the data purity and logical reliability of the load reference value update mechanism are ensured. By setting the constraint that "the complete acquisition time is greater than the shortest alarm trigger time," the system completes a round of stable-state-based sampling for updating the load reference value before any transient or dangerous conditions that could lead to an over-amplitude alarm (such as rapid boom start-up or sudden suspension of the work platform) fully manifest and are identified. This effectively prevents unstable and atypical load data collected during alarm triggering or in critical states from being included in the calculation of historical benchmarks. This isolates normal operating states from alarm-risk states in the time dimension, ensuring that the load reference value always represents a safe and reliable historical operating load, laying a solid data foundation for subsequent accurate causal determination.

[0027] Furthermore, from the time the over-amplitude alarm is triggered until the over-amplitude alarm is deactivated, the load reference value remains unchanged;

[0028] The load reference value is stored when the aerial work platform vehicle loses power and is only cleared to zero when the aerial work platform vehicle enters the retracted state.

[0029] By implementing a data management strategy of "freezing during alarms, retaining during power failures, and resetting upon completion," the uniqueness, stability, and consistency of the load reference value's role in the entire control logic are ensured. Freezing the reference value during an alarm serves as a constant benchmark for determining the alarm's cause, preventing misjudgments or benchmark drift due to data updates. The power-off retention function ensures the continuity of historical operational status information after an unexpected power outage, preventing control logic failure due to power interruption. The completion-of-cycle reset rule resets the system at the complete end of the operational cycle, providing a clean initial state for the next operation. These three elements work together to make the load reference value a reliable, persistent, and logically clear state variable, providing a stable and trustworthy data anchor for intelligent discrimination and hierarchical control, thereby ensuring the reliability and robustness of the entire safety control system's decisions.

[0030] Furthermore, the first safe load threshold is k1 times the rated load of the first operating curve followed by the aerial work vehicle when the over-amplitude alarm is triggered, where k1 is a first safety factor determined based on dynamic stability requirements;

[0031] The second safe load threshold is k2 times the rated load of the first operating curve, where k2 is the second safety factor determined based on static stability requirements, and k2 > k1.

[0032] By precisely anchoring the key decision thresholds (first and second safety load thresholds) in the hierarchical control system to the inherent engineering design standards (dynamic and static stability) of the aerial work platform and its current operating state (rated load of the first operating curve), a quantitative and personalized combination of safety control logic and engineering safety margin is achieved. Using the rated load as a benchmark and multiplying it by coefficients (k1, k2) determined based on stability theory, the safety load thresholds are no longer fixed or empirical values, but rather scientific parameters that dynamically adjust according to the equipment's current operating capacity. This not only ensures that the hierarchical control strategy strictly adheres to the overall machine's dynamic stability (k1), static stability, and structural strength (k2) safety boundaries under any operating condition, providing objective and accurate engineering criteria for whether the equipment can operate safely after overload, but also, by setting a dual-layer threshold of k2 > k1, constructs a smooth and progressive safety decision gradient from "allowed safe operation" to "conditionally allowed" to "absolutely prohibited," maximizing the exploitation and utilization of the equipment's inherent safety potential while ensuring absolute safety, achieving a refined balance between safety and operational flexibility.

[0033] Furthermore, the preset safe operating range corresponding to the real-time load value is specifically as follows:

[0034] If the real-time load value does not exceed the first safe load threshold, then the preset safe operating range is the maximum safe operating range of the first operating curve followed by the aerial work vehicle before the alarm is triggered;

[0035] If the real-time load value exceeds the first safe load threshold, then the pre-stored safe operation curve database is queried according to the real-time load value to determine the higher-level safe operation curve corresponding to the real-time load value, and the maximum safe operation range of the higher-level safe operation curve is taken as the preset safe operation range.

[0036] By establishing a dynamic safety boundary judgment rule that adapts to the overload level, the judgment benchmark for "whether it exceeds the limit" is precisely defined, thereby achieving refined perception of the equipment's risk status. Specifically, based on whether the real-time load exceeds the first safe load threshold based on dynamic stability, the corresponding safe operating range is intelligently selected as the comparison benchmark: in the case of light overload, the original operating curve is still used as the safety boundary, acknowledging its operating capability under dynamic stability; in the case of heavy overload, it automatically switches to a more stringent next-level operating curve boundary to match the higher stability requirements required after the load increases. This case-specific, switchable boundary definition mechanism enables the system to more accurately distinguish between the safe state of "under higher load but not exceeding the new boundary" and the dangerous state of "exceeding the corresponding boundary," providing a correct and reasonable logical premise for subsequent graded handling (especially the "load-range" dual judgment), avoiding misjudgments caused by using a single, rigid safety boundary (such as misjudging the safe position under heavy load as exceeding the limit), thus significantly improving the accuracy of safety assessment and the rationality of control decisions under complex overload conditions.

[0037] Furthermore, it is further determined whether the exceeded amplitude value meets the condition determined based on the ratio between the real-time load value and the second safe load threshold, specifically:

[0038] Determine whether the exceeded amplitude value is less than or equal to a permissible safe overamplitude value, which is determined by the following formula:

[0039] ;

[0040] in, Indicates the permissible safe over-amplitude value; W represents the real-time load value; Indicates the second safe load threshold; This indicates a predetermined baseline overshoot value.

[0041] By introducing a dynamic safety tolerance algorithm based on load ratio, the safety assessment of aerial work platforms exceeding their rated range is upgraded from the rigid "fixed threshold, one-size-fits-all" mode of existing technology to an intelligent mode of "continuously changing with the load, refined and quantitative evaluation." The core of this approach is that the system dynamically calculates the current load based on the aforementioned formula. The maximum safe over-amplitude value allowed below This quantifies and assigns strictly matched safety margins to different overload levels. This innovation is based on engineering mechanics: before reaching the absolute overturning limit, the remaining stability margin of the equipment is proportional to the current load. Therefore, when an overload alarm occurs, the system can accurately determine whether the current exceedance has exhausted the "safety margin budget" corresponding to the load. This allows the equipment to perform a safe reset under moderate and minor overload conditions, provided that dynamic stability and structural safety are absolutely guaranteed, thus opening a reliable safety self-rescue channel. This solution completely overcomes two major shortcomings of existing technologies: 1) It avoids excessively conservative locking due to the inability to quantify risks, significantly improving operational efficiency and equipment utilization; 2) It completely replaces unauthorized operations relying on operator subjective judgment with objective engineering calculations, fundamentally eliminating major safety risks caused by human error.

[0042] Furthermore, the process for determining the benchmark over-amplitude includes:

[0043] Use the second safe load threshold as the load input condition;

[0044] Based on the dynamic stability analysis and structural strength analysis of the aerial work vehicle under the worst working posture, the following calculation is made: under the load input condition, the maximum over-range distance that can still maintain the dynamic stability of the whole vehicle and keep the stress of the key structure within the safe range after the working amplitude of the work column exceeds the maximum safe working amplitude of its corresponding next-level working curve is calculated, and this maximum over-range distance is stored as the benchmark over-amplitude value.

[0045] By selecting the combination of the most unfavorable conditions—the "second safe load threshold" (i.e., the static stability limit load) and the "worst stable operating posture"—as input, detailed dynamic stability and structural strength simulation calculations are performed. The determined benchmark over-amplitude value is essentially an absolute limit point of the equipment on the theoretical safety boundary. Using this fully safety-verified limit value as the benchmark parameter in the dynamic calculation formula ensures that all subsequent allowable safe over-amplitude values ​​calculated based on real-time load ratios inherit this most conservative safety gene. This allows the entire intelligent tolerance control strategy to pursue flexibility while firmly anchoring its safety baseline within the safety domain of the overall machine design. This fundamentally guarantees that the system's "permissible action" decisions under any circumstances will not exceed the pre-verified engineering safety envelope, achieving an organic combination of flexibility expansion and intrinsic safety protection.

[0046] Furthermore, the movement in the safe direction includes one or more of the following: boom retraction, boom descent, and boom rotation toward the vehicle's center of gravity.

[0047] The system clarifies the specific and operable safety reset paths that the equipment should execute after determining that a permissible action has been taken. Examples include "retracting" to reduce the overturning moment, "descending" to lower the center of gravity, and "rotating towards the support center of gravity" to utilize a more stable support area. This specific definition avoids ambiguity in control commands, ensuring that the actuators can accurately and consistently execute the most effective escape actions. This unambiguously translates the safety intent of the algorithmic decision into mechanical actions that genuinely improve equipment stability, enhancing the practicality and reliability of the entire intelligent control system.

[0048] Based on the same concept, the present invention also provides an intelligent control system for aerial work platforms, including a processor, a memory, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, it implements the intelligent discrimination and hierarchical control method for over-range alarm of aerial work platforms as described above.

[0049] Compared with existing technologies, the advantages of this invention are: while ensuring absolute safety, it significantly improves the intelligence level and operational efficiency of aerial work platforms. Specifically, this is reflected in:

[0050] By dynamically maintaining and comparing load reference values ​​with real-time loads, the system can accurately distinguish whether over-amplitude alarms are caused by actual loading or by non-loading factors such as boom posture changes. For the latter, the system allows the equipment to automatically and safely reset, effectively avoiding unnecessary work interruptions caused by false alarms in existing technologies and ensuring construction continuity.

[0051] For genuine overload, this invention abandons the dangerous practices of "one-size-fits-all" locking or relying on human "overreach," and creatively introduces a safety tolerance algorithm based on load ratio. This algorithm dynamically calculates the still permissible safe operating range (i.e., the "safety budget") according to the severity of the overload, enabling the equipment to "self-rescue" within strict safety boundaries under moderate and minor overload conditions. This eliminates the risk of overturning while minimizing equipment locking and waiting for rescue, greatly improving operational flexibility and equipment utilization.

[0052] The core parameters of the entire control logic (such as the safe load threshold and the reference over-amplitude value) are all derived from the inherent engineering safety standards of the equipment, such as dynamic / static stability, and are determined through pre-calculation under the worst operating conditions. This ensures that every "allow / prohibit" action decision of the system is based on objective engineering calculations and quantitative analysis, completely replacing the "overstepping" judgments that rely on the operator's subjective experience. This eliminates the safety hazards caused by human error at the source and achieves automated and inherently safe safety management. Attached Figure Description

[0053] To more clearly illustrate the technical solution of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only one embodiment of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0054] Figure 1 This is a schematic diagram of the operating curves of the equipment under different load ranges in an embodiment of the present invention;

[0055] Figure 2 This is a schematic diagram of the working curve of the auxiliary boom of the hybrid boom aerial work vehicle in this embodiment of the invention when the main boom luffing angle is less than or equal to the critical angle under a specific load range and slewing area.

[0056] Figure 3 This is the corresponding embodiment of the present invention. Figure 2 A schematic diagram of the auxiliary boom's operating curve when the main boom's luffing angle is greater than the critical angle, under the same equipment and load range;

[0057] Figure 4 This is a flowchart of the intelligent discrimination and hierarchical control method for over-range alarm of aerial work vehicle in an embodiment of the present invention;

[0058] Figure 5 This is a schematic diagram of the working curves of each load range in the projection direction in an embodiment of the present invention. Detailed Implementation

[0059] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0060] The technical solution of the present invention will be described in detail below with reference to specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments.

[0061] Example 1

[0062] In the present invention, the so-called "operation curve" refers to a safety boundary curve preset based on the relationship between the load and the operation amplitude (or radius) of an aerial work platform to ensure the overall stability and structural safety of the machine. As the load increases, the safety boundary switches to a more stringent curve. Specifically, the "first operation curve" refers to the safety operation boundary curve that the aerial work platform currently follows when the over-amplitude alarm is triggered; the "next-level operation curve" refers to the safety operation boundary curve corresponding to a load range higher (or more stringent) than the current load. For example, when the load increases from the 120 kg range to the 260 kg range, the corresponding operation curve switches from the "first operation curve" to the "next-level operation curve".

[0063] The core of the present invention is to provide an intelligent discrimination and hierarchical control method for the over-amplitude alarm of an aerial work platform to solve the technical problems in the prior art, such as the inability to distinguish the alarm reasons (true overload and curve switching) and the single disposal strategy ("one-size-fits-all" locking or relying on dangerous "over-authorization"). The method of the present invention realizes the unified improvement of safety and operation flexibility through two major steps: intelligent diagnosis of alarm reasons and hierarchical safety control.

[0064] Figure 1 It is a graph showing the operation of the equipment (i.e., the aerial work platform) according to an embodiment of the present invention in different load ranges. Figure 1 It shows a stepped negative correlation between the load (W) of the work bar of the aerial work platform and the maximum allowable operation amplitude or radius (R). Figure 1 The safety operation boundary curves corresponding to different load ranges (such as W≤W1, W1<W≤W2, W2<W≤W3) are marked, and key concept areas such as the allowable range of dynamic stability (R2<R≤R1) and the allowable range of static stability and structural safety (R2<R≤R2+L1, where L1 is the reference over-amplitude value) are示例性 marked to illustrate the hierarchical control logic of the present invention. As Figure 1 shown, the smaller the load W, the larger the allowable operation amplitude (radius R), forming multiple stepped safety operation boundary curves such as W1, W2, and W3.

[0065] One of the technical problems to be solved by the present invention, namely the false over-amplitude caused by the operation curve switching, is particularly prominent in aerial work platforms, especially in the hybrid boom type. As Figure 2 shown in Figure 3 :

[0066] Figure 2 It shows that when the luffing angle of the main boom is less than or equal to a certain critical angle, the auxiliary boom can be fully extended for operation, and its safety boundary forms a circular arc with a relatively large radius. Figure 2 shows that in this posture, the auxiliary boom can be fully extended as a free boom, and its safety operation boundary is approximately a circular arc with the full extension length of the auxiliary boom as the radius, indicating that the allowable operation range is relatively large in this state.

[0067] Figure 3 This shows that when the boom luffing angle is greater than the critical angle, the working range of the jib is limited for the sake of overall stability and structural safety, and its safety boundary shrinks significantly with different angles. Figure 3 The data shows that due to changes in the main boom's posture, the working range of the auxiliary boom is limited. Its maximum permissible working radius (limited length) varies with the auxiliary boom's angle, forming a... Figure 2 A distinctly different, range-shrinking safety boundary curve.

[0068] Therefore, it can be concluded that during the continuous luffing and lifting of the main boom and the crossing of the critical angle, the permissible safe operating range of the equipment will increase from... Figure 2 The curve shown switches to Figure 3 The curve shown illustrates this. If the auxiliary boom is in a near-horizontal position at this time, this switch will cause a drastic jump in the allowable amplitude. When the equipment crosses this switching point during normal operation, even if the load on the work platform remains unchanged, its real-time working position may be immediately judged as over-amplitude due to the sudden inward contraction of the new boundary, thus triggering a serious amplitude limit alarm. This is a typical "non-load-related" false alarm caused by the switching of the system's own safety rules.

[0069] The control method provided by this invention is designed to accurately identify and properly handle such alarms, ensuring they do not disrupt normal operations. This method is a continuously operating, dynamically decision-making closed-loop system, whose core process can be summarized into two stages: data preparation under normal conditions and intelligent response after an alarm is triggered.

[0070] Phase 1: Routine data preparation (offline / online maintenance).

[0071] Throughout the entire equipment operation, regardless of whether an alarm occurs, the system continuously executes step S1: establishing and maintaining a dynamic load reference value. This is a background-running baseline data update mechanism independent of alarm events. Its purpose is to always maintain a reliable reference value that represents the equipment's recent operating load under safe conditions. This reference value is the basis for all subsequent intelligent judgments and must be prepared and updated before any over-range alarm occurs.

[0072] Phase Two: Alarm Triggering and Intelligent Response.

[0073] When the equipment triggers a severe overload alarm due to the operating range touching or exceeding the safety boundary, the system immediately switches from normal maintenance mode to emergency response mode, sequentially executing step S3: overload alarm triggering and intelligent cause determination, and step S4: graded safety control for actual overload. The entire control process is as follows: Figure 4 As shown.

[0074] Step S1: Establish and maintain a dynamically updated load reference value.

[0075] Step S1 aims to obtain a reliable historical benchmark for determining whether a sudden change has occurred in the load. The specific implementation process is as follows:

[0076] Data Sampling: When the aerial work platform is in normal working condition (no over-amplitude alarm triggered) and the boom begins to move (i.e., the boom movement output signal is valid), the aerial work platform's control system initiates data acquisition. The real-time load value of the work platform's load cell is continuously read at a predetermined sampling period T (e.g., set to 50 times the control system's scan period).

[0077] Sliding window storage: The control system maintains a sliding window of length N (e.g., N=5). Each time a new real-time load value is acquired, it is stored in the sliding window, overwriting the oldest real-time load value in the window, thus always keeping the sliding window containing the most recent N real-time load values.

[0078] Load reference value calculation and update: When the boom movement stops (i.e., the boom movement output signal is turned off), the system triggers a load reference value update. If the sliding window is full of N real-time load values ​​at this time (i.e., one complete sampling cycle has been completed), the arithmetic mean of the N real-time load values ​​in the current sliding window is calculated, and this average is updated and stored as the load reference value. If the sliding window is not full (i.e., the boom movement time is too short to complete N acquisitions), the load reference value is not updated this time, and the load reference value remains unchanged from the last valid update. This value is non-volatilely stored when the system loses power.

[0079] Freeze during alarm period: From the triggering of the over-amplitude alarm until the over-amplitude alarm is completely deactivated, the load reference value remains unchanged, ensuring that the judgment benchmark is a stable and reliable pre-alarm state during the alarm handling process.

[0080] Zeroing upon vehicle closure: When the aerial work platform vehicle completes its work and enters the closure state, the system will reset the load reference value to zero, establishing a clean initial state for the next operation.

[0081] Timing Guarantee: The selection of sampling periods T and N must ensure that the total time (N*T) for completing one round of N samplings is greater than the shortest processing time from detecting boom movement to potentially triggering an over-amplitude alarm. This avoids incorporating unstable transient data from alarms into the calculation of load reference values.

[0082] Step S2: Over-range monitoring and alarm triggering.

[0083] Step S2 runs in parallel with step S1 during equipment operation and is the prerequisite logic for initiating subsequent intelligent cause determination.

[0084] The system acquires the current working load (i.e., the real-time load value of the working platform) and the current posture parameters of the equipment (including boom luffing angle, telescopic length, slewing area, etc.) in real time. Based on the load range to which the current working load belongs and the current posture parameters, it queries the pre-stored safe operating curve database to determine the maximum safe operating amplitude allowed by the equipment under the current state. The safe operating curve database is pre-established and stored based on the analysis of vehicle stability and structural strength, and defines corresponding safety limits for different loads and postures.

[0085] The system acquires the actual working radius of the work platform or boom end in real time through sensor measurements and kinematic model calculations. It continuously compares the actual working radius with the maximum permissible safe working radius. When the actual working radius reaches or exceeds the maximum permissible safe working radius, it is considered an over-range operation. Once the over-range condition is met, the control system immediately generates a "serious over-range alarm" event signal. This signal marks the beginning of a new control cycle requiring emergency response.

[0086] Step S3: Trigger the overload alarm and determine the cause of the overload alarm based on whether the increment of the real-time load value relative to the load reference value exceeds the preset load change threshold.

[0087] When an over-amplitude alarm event is triggered, the system immediately interrupts the normal control process and switches to the core response logic of this invention: determining the cause of the over-amplitude alarm.

[0088] The system immediately reads the load reference value, representing the historical safe load state, maintained in step S1 before the alarm; simultaneously, it acquires the real-time load value of the work column at the moment the alarm is triggered (this value is usually the same as or a subsequent value of the current work column load in the alarm trigger judgment logic at the same moment). The difference between the real-time load value of the work column at the moment the alarm is triggered and the load reference value is calculated, thus obtaining the load increment; the load increment is then compared with a preset load change threshold (e.g., twice the error of the weighing sensor).

[0089] If the load increment is greater than the preset load change threshold, it is determined that the over-amplitude alarm is caused by the load increase, and the graded control in step S4 is executed.

[0090] If the load increment is less than or equal to the preset load change threshold, the system determines that the over-amplitude alarm is caused by factors other than load increase (such as the boom passing through a critical angle, or the switching of the work curve caused by slewing into different areas). In this case, the system allows the boom to perform movements in a safe direction (such as retraction, descent, or slewing towards the support stability zone) to automatically deactivate the alarm and resume normal operation.

[0091] Step S4: Graded safety control strategy for actual overload.

[0092] For overload alarms determined to be genuine overloads, the system implements refined, tiered control based on the severity of the overload. First, two key safe load thresholds are determined:

[0093] First safe load threshold W 1,th This is set to k1 times the rated load of the current safe operating boundary curve (referred to as the first operating curve) that the equipment follows when an alarm is triggered. k1 is the first safety factor determined based on the equipment's dynamic stability requirements, and is usually taken as k1=1.25.

[0094] Second safety load threshold W 2,th : Set to k2 times the rated load of the first operating curve. k2 is the second safety factor determined based on the static stability and structural strength requirements of the equipment, and k2 > k1, usually k2 = 1.5.

[0095] The hierarchical control logic is as follows:

[0096] Level 1 (Minor Overload) Control: If the real-time load value in the work area is ≤ the first safe load threshold W 1,th If this is the case, the boom is allowed to move in a safe direction. Since the load has not exceeded the dynamic stability requirements, the equipment is safe within its original operating range.

[0097] Level 2 (Medium Overload) Control: If the first safe load threshold W 1,th <Real-time load value in the work column ≤ Second safe load threshold W 2,th The second-level control is then divided into two sub-judgments:

[0098] Sub-judgment A (Amplitude Not Exceeded): Determines whether the current operating amplitude exceeds the preset safe operating amplitude corresponding to the real-time load value in the work column. Here, the preset safe operating amplitude is determined as the maximum safe operating amplitude of the operating curve corresponding to the next level of load range to which the real-time load value belongs (e.g., ...). Figure 1 (R2 in the middle).

[0099] If the load is within limits, it means that although the load is high, the boom position is still within stricter safety boundaries. In this case, the boom is allowed to move in a safe direction, but it is prohibited from moving in a direction that increases the working radius.

[0100] If the threshold is exceeded, then proceed to the core quantitative security assessment (sub-judgment B, i.e., proportion judgment).

[0101] Sub-judgment B (Amplitude Exceeded): If the current operating amplitude exceeds the preset safe operating amplitude corresponding to the real-time load value of the work column, a quantitative safety assessment is performed. The excess amplitude value ΔR (i.e., the difference between the current operating amplitude and the preset safe operating amplitude) is calculated, and it is determined whether the excess amplitude value ΔR meets the following safety condition based on proportional relationships:

[0102] (1)

[0103] Where W represents the real-time load value; Indicates the second safe load threshold; This represents a predetermined baseline overshoot value. This baseline overshoot value is determined through engineering simulation and calculation. Specifically, it includes:

[0104] Establish analysis models: Based on the three-dimensional design model of the aerial work platform vehicle, establish a multi-body dynamics model including the boom, turntable, vehicle body and outriggers, as well as a finite element stress analysis model of key load-bearing structures (such as boom pins and luffing cylinder supports).

[0105] Set working conditions and loads: In the multibody dynamics model, adjust the boom to the preset posture with the minimum stability margin (such as maximum amplitude, medium height), and apply a load equal to the second safe load threshold to the work area.

[0106] Perform iterative calculations: While keeping the load constant, gradually and virtually increase the working range of the work column in the simulation, so that it exceeds the boundary of the next level of work curve (i.e., the more stringent safety work boundary curve corresponding to the increase in load).

[0107] Determining the Limit Value: Real-time monitoring of the vehicle's rollover stability coefficient and the maximum equivalent stress of key structures in the simulation results. Iteration stops when the stability coefficient drops to 1.0 (i.e., the critical rollover state) or the stress in the key structure reaches the preset safety factor (e.g., 2.0) of the material's yield limit. At this point, the distance the virtual overshoot in the workbench is the calculated baseline overshoot value.

[0108] Result storage: The calculated baseline overshoot value is associated with the corresponding second safety load threshold and vehicle model information and pre-stored in the non-volatile memory of the control system.

[0109] In another implementation, determining the baseline overshoot value is a standard engineering analysis component of the aerial work platform product design phase. Those skilled in the art can obtain this value through calculation or simulation, based on the calculation methods for overturning stability and structural strength verification criteria in the national standard GB / T3811-2008 "Crane Design Specification," combined with specific vehicle model parameters. The specific value varies depending on the vehicle model design and is pre-set as a fixed parameter in the control system before the product leaves the factory.

[0110] If formula (1) is satisfied, the current working range is determined to be within the safety tolerance, and the boom is allowed to move in a safe direction; if formula (1) is not satisfied, the risk is determined to be too high, and boom movement is prohibited.

[0111] Level 3 (Severe Overload) Control: If the real-time load value exceeds the second safe load threshold W2,th, boom movement is prohibited. The only way to lift the restriction is to reduce the load on the work platform until the real-time load value drops to a safe range.

[0112] Figure 5 Specific numerical examples (such as load curves for 120kg, 260kg, and 400kg) further illustrate the complexity of how the safe operating range varies with the position of the slewing area under different load ranges. Figure 5 The text clearly demonstrates that when the equipment rotates from a large operating area to a small operating area, an overload alarm may be triggered immediately at the curve switching point. It also shows the working conditions where a load jump to a higher range due to loading (such as jumping from a 120kg curve to a 260kg or 400kg curve) triggers a real overload alarm.

[0113] Suppose the equipment was originally operating at the maximum amplitude position of the 120kg load operating curve (i.e., the rated load is 120kg), at which time the load reference value was maintained at a level close to 120kg.

[0114] Scenario 1 (Curve Switching): The equipment rotates into a more restrictive area, triggering an overload alarm. After step S3, if the load increment is less than or equal to the preset load change threshold, the system determines that the overload alarm is not caused by an increase in load and allows the boom to safely adjust its posture to clear the alarm.

[0115] Scenario 2 (Loaded to 150kg): When a heavy object is loaded in the air, the real-time load value reaches 150kg, triggering an overload alarm. If the load increment exceeds the preset load change threshold, it is determined to be a genuine overload, i.e., an overload alarm caused by an increase in load. The first safe load threshold is 1.25 * 120kg = 150kg, and the second safe load threshold is 1.5 * 120kg = 180kg. Since 150kg ≤ 150kg, the first-level control condition is met, allowing the boom to retract.

[0116] Scenario 3 (Loaded to 170kg and exceeding the allowable range): After loading, the real-time load value reaches 170kg, and the operating range exceeds the boundary R2 of the 260kg curve (i.e., ΔR>0). This situation triggers Level 2 control. The system calculates the permissible safe over-range value L. per =(170 / 180)* ( (This is the maximum excess distance calculated for 180kg). If the actual ΔR≤L per If it is, safe retraction is allowed; otherwise, the action is prohibited.

[0117] Scenario 4 (Loaded to 190kg): If the real-time load value is 190kg > 180kg, the system will directly enter the third level of control, prohibiting all actions and requiring weight reduction.

[0118] To fully demonstrate the universality of the method of this invention, the control logic when the equipment originally followed a higher load curve is further explained. Suppose that the equipment was originally operating at the maximum amplitude position of the 260kg load operating curve (i.e., the rated load is 260kg), at which time the load reference value is maintained at a level close to 260kg.

[0119] The first safe load threshold is 1.25 * 260 kg = 325 kg, and the second safe load threshold is 1.5 * 260 kg = 390 kg. The corresponding next-level operating curve is the 400 kg load operating curve.

[0120] The baseline overshoot value is the maximum safe distance allowed beyond the 400kg operating curve boundary, calculated using the second safe load threshold of 390kg.

[0121] Under this configuration, the control method responds to various loading scenarios as follows:

[0122] Scenario 5 (Loaded to 320kg): A heavy load is loaded in mid-air, and the real-time load value reaches 320kg, triggering an overload alarm. Upon assessment, the load increment exceeds the preset load change threshold, constituting a genuine overload. Since 320kg ≤ 325kg, the first-level control condition is met, and the system allows the boom to retract safely.

[0123] Scenario 6 (Loaded to 370kg with slight overload): After loading, the real-time total load reaches 370kg, and the operating range exceeds the boundary R3 of the 400kg curve (i.e., ΔR>0). This scenario triggers Level 2 control. The system calculates the permissible safe overload value L. per =(370 / 390)* If the actual ΔR≤L per If the boom retracts safely, then the boom is permitted to retract safely; otherwise, the action is prohibited.

[0124] Scenario 7 (Loaded to 400kg): Real-time load value 400kg > 390kg, directly enters the third level of control, the system prohibits all boom movements, and the restriction can only be lifted after the weight is reduced.

[0125] The examples using two consecutive load ranges of 120kg and 260kg demonstrate that the intelligent discrimination and hierarchical control method of this invention can be adaptively applied regardless of the initial operating curve position of the equipment: by multiplying the rated load of the current operating curve by a safety factor (k1, k2) to obtain the first and second safe load thresholds for the current scenario, and based on the benchmark over-amplitude value calculated for the second safe load threshold... Dynamic tolerance judgment is performed. This demonstrates that the method of the present invention has broad applicability and consistent logic, and can cover over-amplitude safety control across the entire load spectrum of aerial work platforms.

[0126] Through the above specific embodiments, the present invention achieves:

[0127] Accurately distinguish the root cause of alarms to avoid work interruptions caused by misjudgment; conduct quantitative risk assessment based on engineering standards to provide safe self-rescue possibilities for medium overload conditions while ensuring dynamic stability and structural safety, significantly improving operational flexibility; completely replace subjective "unauthorized" operations with objective algorithms to improve the level of inherent safety.

[0128] Example 2

[0129] This invention also provides an intelligent control system for aerial work platforms. The control system includes a memory, a processor, and a computer program or instructions stored in the memory. The processor executes the computer program or instructions to implement the intelligent discrimination and hierarchical control method for over-range alarm of aerial work platforms in this invention.

[0130] Although not shown, the control system includes a processor that performs various appropriate operations and processes based on programs and / or data stored in read-only memory (ROM) or loaded from a storage portion into random access memory (RAM). The processor can be a multi-core processor or may contain multiple processors. In some embodiments, the processor may include a general-purpose main processor and one or more specialized coprocessors, such as a central processing unit, graphics processing unit (GPU), neural network processor (NPU), digital signal processor (DSP), etc. Various programs and data required for device operation are also stored in RAM. The processor, ROM, and RAM are interconnected via a bus. Input / output (I / O) interfaces are also connected to the bus.

[0131] The processor and memory described above are used together to execute programs / instructions stored in the memory. When the program / instructions are executed by the computer, they can implement the methods, steps, or functions described in the above embodiments.

[0132] Although not shown, embodiments of the present invention also provide a computer-readable storage medium storing a computer program or instructions that, when executed by a processor, implement the intelligent discrimination and hierarchical control method for over-range alarm of aerial work vehicles in embodiments of the present invention.

[0133] Readable storage media include both permanent and non-permanent, removable and non-removable media that can store information by any method or technology. Information can be computer-readable instructions, data structures, program modules, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0134] The above description only discloses specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or modifications that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for intelligent discrimination and hierarchical control of over-range alarm for aerial work platforms, characterized in that, The control method includes: Maintain a dynamically updated load reference value; wherein the load reference value is used to characterize the load status of the aerial work platform before the over-amplitude alarm occurs; When an overload alarm occurs, the real-time load value of the current work column is obtained. Based on whether the increment of the real-time load value relative to the load reference value exceeds a preset load change threshold, it is determined whether the overload alarm is caused by an increase in load. If the over-amplitude alarm is caused by factors other than increased load, the boom is allowed to move in a safe direction to deactivate the alarm. If the overload alarm is caused by an increase in load, the following hierarchical control steps are executed: If the real-time load value does not exceed the first safe load threshold, the boom is allowed to move in a safe direction; If the real-time load value exceeds the first safe load threshold but does not exceed the second safe load threshold, then first determine whether the current working range exceeds the preset safe working range corresponding to the real-time load value; if it does not exceed, then the boom is allowed to move in a safe direction and is prohibited from moving in a direction that increases the working range; if it exceeds, then further determine whether the exceeded range value meets the condition determined based on the ratio between the real-time load value and the second safe load threshold; if it meets the condition, then the boom is allowed to move in a safe direction; if it does not meet the condition, then the boom movement is prohibited. If the real-time load value exceeds the second safe load threshold, boom movement is prohibited.

2. The intelligent discrimination and hierarchical control method for over-range alarm of aerial work vehicles according to claim 1, characterized in that, The load reference value is dynamically updated through the following steps: When the aerial work vehicle is in normal operation without triggering the over-amplitude alarm, in response to the valid output signal of the boom action, it continuously collects the real-time load value of the work column at a predetermined sampling period and stores the N most recently collected real-time load values ​​in a sliding window. In response to the shutdown of the boom action output signal, the average value is calculated based on the N real-time load values ​​within the sliding window, and the average value is updated as the load reference value.

3. The intelligent discrimination and hierarchical control method for over-range alarm of aerial work vehicles according to claim 2, characterized in that, The time required from the start of data collection to filling the sliding window is greater than the shortest time required for the aerial work platform vehicle to start moving from the boom and trigger the over-amplitude alarm.

4. The intelligent discrimination and hierarchical control method for over-range alarm of aerial work vehicles according to claim 2, characterized in that, The load reference value remains unchanged from the time the over-amplitude alarm is triggered until the over-amplitude alarm is cleared. The load reference value is stored when the aerial work platform vehicle loses power and is only cleared to zero when the aerial work platform vehicle enters the retracted state.

5. The intelligent discrimination and hierarchical control method for over-range alarm of aerial work vehicles according to claim 1, characterized in that, The first safe load threshold is k1 times the rated load of the first operating curve followed by the aerial work vehicle when the over-amplitude alarm is triggered, where k1 is the first safety factor determined based on dynamic stability requirements; The second safe load threshold is k2 times the rated load of the first operating curve, where k2 is the second safety factor determined based on static stability requirements, and k2 > k1.

6. The intelligent discrimination and hierarchical control method for over-range alarm of aerial work vehicles according to claim 1, characterized in that, The preset safe operating range corresponding to the real-time load value is specifically as follows: If the real-time load value does not exceed the first safe load threshold, then the preset safe operating range is the maximum safe operating range of the first operating curve followed by the aerial work vehicle before the alarm is triggered; If the real-time load value exceeds the first safe load threshold, then the pre-stored safe operation curve database is queried according to the real-time load value to determine the higher-level safe operation curve corresponding to the real-time load value, and the maximum safe operation range of the higher-level safe operation curve is taken as the preset safe operation range.

7. The intelligent discrimination and hierarchical control method for over-range alarm of aerial work vehicles according to claim 1, characterized in that, Further determine whether the exceeded amplitude value meets the condition determined based on the ratio between the real-time load value and the second safe load threshold, specifically: Determine whether the exceeded amplitude value is less than or equal to a permissible safe overamplitude value, which is determined by the following formula: ； in, Indicates the permissible safe over-amplitude value; W represents the real-time load value; Indicates the second safe load threshold; This indicates a predetermined baseline overshoot value.

8. The intelligent discrimination and hierarchical control method for over-range alarm of aerial work vehicles according to claim 7, characterized in that, The process for determining the benchmark over-amplitude value includes: Use the second safe load threshold as the load input condition; Based on the dynamic stability analysis and structural strength analysis of the aerial work vehicle under the worst working posture, the following calculation is made: under the load input condition, the maximum over-range distance that can still maintain the dynamic stability of the whole vehicle and keep the stress of the key structure within the safe range after the working amplitude of the work column exceeds the maximum safe working amplitude of its corresponding next-level working curve is calculated, and this maximum over-range distance is stored as the benchmark over-amplitude value.

9. The intelligent discrimination and hierarchical control method for over-range alarm of aerial work platform vehicles according to any one of claims 1 to 8, characterized in that, The movement in the safe direction includes one or more of the following: boom retraction, boom descent, and boom rotation toward the vehicle's center of gravity.

10. An intelligent control system for an aerial work platform, comprising a processor, a memory, and a computer program stored in the memory and executable on the processor, characterized in that, When the processor executes the computer program, it implements the intelligent discrimination and hierarchical control method for the over-amplitude alarm of the aerial work vehicle as described in any one of claims 1 to 9.

Images