A remote control system for a port container crane

Abstract

The application discloses a kind of port container crane remote control systems.The system is by network monitoring module, controller, sensor group, video encoder and remote operation end composition.System utilizes sensor group to obtain sling height, trolley and sling speed, target box top distance and other physical parameters, calculates the bandwidth allocation proportion coefficient of video area of interest, and sets mandatory numerical interval constraint, realizes the accurate mapping of visual resource and operation urgency.Aiming at the mechanical inertia of trolley mechanism, the system adopts the method of trend prediction and physical boundary limiting to smooth compensation of control instruction, limits the change rate of prediction instruction by maximum allowable acceleration, solves the motion disorder problem caused by network jitter.The application improves the system fault tolerance capability under extreme conditions, ensures the high-definition feedback of remote box operation and intrinsic safety.

Description

Technical Field

[0001] This invention relates to the field of intelligent port automation control, specifically to a video bandwidth adjustment and command smoothing compensation system based on mechanical operation status perception. Background Technology

[0002] In the process of building automated smart ports, remote control technology for container cranes has become a key means to improve operational efficiency and inherent safety. By deploying high-sensitivity cameras at the crane end and using low-latency networks, operators can achieve precise monitoring and real-time operation of on-site lifting operations from a remote control center.

[0003] First, the current compensation methods for commands are too vague and fail to adapt to the complex dynamics of cranes. When dealing with data loss caused by network jitter, existing compensation strategies typically employ a uniform command hold or discard scheme for all mechanisms, without considering the order-of-magnitude difference in mechanical inertia between the trolley traveling mechanism and the lifting mechanism of the crane. This simplistic compensation logic is highly susceptible to causing motion misalignment due to command jumps when dealing with the highly inertial trolley mechanism, leading to a serious risk of secondary swaying of the lifting device and threatening on-site operational safety.

[0004] Furthermore, existing adaptive bandwidth allocation algorithms generally lack defensive physical boundary constraints. When allocating bandwidth resources, current solutions often fail to consider the physical limits of the video encoder and the basic requirements of visual environment perception. If the calculated allocation ratio tends to extreme values ​​such as 0 or 1, it can lead to a complete blackout of the background area of ​​the video screen or the collapse of the encoder logic in the core operating area. Due to the lack of necessary fault tolerance, the system struggles to guarantee basic operational visibility and stability under extreme network or operating environments. Summary of the Invention

[0005] To achieve the above-mentioned objectives, this invention provides a remote control system for a port container crane, including a network monitoring module, a controller, a sensor group, a video encoder, and a remote operation terminal; the network monitoring module is used to monitor the real-time available total bandwidth and latency gradient of the network; the sensor group is used to acquire the real-time operating parameters of the crane; the system dynamically adjusts the bandwidth allocation ratio of the region of interest in the video according to the real-time available total bandwidth, latency gradient, and real-time operating parameters, and performs smooth compensation for control commands.

[0006] Furthermore, the real-time operation parameters specifically include: the real-time height of the lifting device collected by the absolute encoder, the current running speed of the trolley fed back by the frequency converter, the rated maximum speed of the trolley as an inherent parameter of the system, the current lifting speed of the lifting device fed back by the frequency converter, the distance between the center point of the lifting device and the top surface of the target box obtained by the laser rangefinder, the pixel area of ​​the entire frame video, and the pixel area of ​​the core operation area.

[0007] Optionally, the dynamic adjustment of the bandwidth allocation ratio of the video region of interest specifically includes: calculating the real-time bandwidth allocation ratio coefficient of the core working area of ​​the video using the real-time height of the lifting device, the current running speed of the trolley, the rated maximum speed of the trolley, the current lifting speed of the lifting device, the distance between the center point of the lifting device and the top surface of the target box, and the video pixel area ratio. The physical motion flux (dynamic energy flow composed of displacement, velocity, and height) of the crane working space is mapped and matched with the information flow at the video coding level (pixel density flow composed of bitrate weight allocation), so that the investment of visual resources is dynamically distributed in accordance with the urgency of the work stage.

[0008] Furthermore, the calculation of the real-time bandwidth allocation ratio coefficient of the core video operation area specifically includes: constructing a mathematical model containing a negative feedback adjustment term and a positive feedback enhancement term; wherein the negative feedback adjustment term is composed of the product of the current running speed of the trolley and the real-time height of the spreader, and is used to characterize the displacement characteristics during the large-scale transportation stage; the positive feedback enhancement term is composed of the sum of the rated maximum speed of the trolley and the current lifting speed of the spreader, the distance between the center point of the spreader and the top surface of the target box, and the ratio of video pixel area, and is used to characterize the proximity perception characteristics during the box operation stage.

[0009] Furthermore, the real-time bandwidth allocation ratio coefficient is subject to physical boundary constraints, specifically including: forcibly constraining the bandwidth allocation ratio coefficient within a specific numerical range by using a preset constant, ensuring that the background area always retains a minimum amount of bandwidth resources under extreme operating conditions, and preventing encoder underlying logic errors or complete loss of context reference of the screen.

[0010] Furthermore, the smooth compensation of the control commands specifically includes: splitting the control commands into trolley horizontal speed commands and lifting speed commands for different degrees of freedom of the mechanism, and executing special compensation logic for trolley horizontal speed commands with significant mechanical inertia characteristics.

[0011] Optionally, the specific compensation logic for the horizontal speed command of the trolley with mechanical inertia characteristics includes: real-time monitoring of the trolley command sequence and corresponding command cycle; when the network monitoring module detects an abnormal delay or command loss, linear trend prediction is performed based on the command values ​​of multiple preceding cycles to simulate the handle movement trend, generating a predicted command, and physical boundary limiting is performed in combination with the trolley mechanism's unique maximum allowable acceleration.

[0012] Furthermore, the physical boundary limiting based on the maximum permissible acceleration of the trolley mechanism specifically includes: comparing the absolute value of the difference between the predicted command of the current cycle and the executed command of the previous cycle; if the difference does not exceed the product of the maximum permissible acceleration and the command cycle, then the predicted command is executed; if the difference exceeds the product of the maximum permissible acceleration and the command cycle, then the direction of motion is determined according to the sign function, and a safety increment determined by the maximum permissible acceleration is superimposed on the command of the previous cycle.

[0013] Furthermore, the system's modules employ a series feedback mechanism, specifically including: a network monitoring module outputting real-time bandwidth and time delay gradient parameters; a bandwidth allocation module receiving the bandwidth parameters and calculating the allocation ratio in conjunction with the pose parameters fed back by the controller, which is then directly used as the input parameters for the video encoder; and an instruction compensation module automatically triggering when the time delay gradient is abnormal, calling the corresponding handle instruction sequence for the trolley speed to perform amplitude limiting prediction, and sending the processed execution instruction to the crane frequency converter.

[0014] Furthermore, the parameters called in the amplitude limiting prediction process specifically include: the pose parameters called by this module are consistent with the parameters such as the height of the sling, the speed of the trolley, and the target distance used in the bandwidth allocation module calculation process. Specifically, the parameters such as the height of the sling, the speed of the trolley, and the target distance are synchronously stamped through a unified sampling clock and then entered into the data pool.

[0015] The remote control system for port container cranes described in this invention achieves the following significant technical effects through the implementation of the above technical solution: This invention introduces real-time height and distance parameters of the spreader to the target, enabling the system to automatically switch to ultra-high-definition mode during the operation phase when approaching the target. This not only improves the success rate of remote control operations during critical container alignment moments but also effectively saves network bandwidth resources during non-critical phases, achieving precise matching of visual feedback with the urgency of the operation.

[0016] This invention presents a command smoothing compensation logic designed for the degrees of freedom of the trolley, fully considering the inertial characteristics of the mechanical mechanism. By combining trend prediction with physical acceleration limiting, it solves the problems of mechanical shock and secondary swaying of the lifting device caused by network instability, enabling remote control to achieve smoothness and safety comparable to local operation.

[0017] This invention clearly defines the boundary values ​​for the bandwidth allocation ratio, which not only prevents the video encoder from crashing due to excessive bitrate gradients under extreme data fluctuations, but also ensures that even during the fine-tuning of containers, operators can still perceive the surrounding environment, such as vehicles or personnel in neighboring containers, through the reserved background bandwidth, providing multi-dimensional operational safety assurance. Attached Figure Description

[0018] Figure 1This is a schematic diagram of the execution flow of the remote control system for port container cranes described in this invention; Figure 2 This is a schematic diagram of the architecture of the remote control system for port container cranes described in this invention; Figure 3 This is a schematic diagram of the electronic terminal structure described in this invention. Detailed Implementation

[0019] The present invention will now be described in detail with reference to the specific embodiments shown in the accompanying drawings. However, these embodiments do not limit the present invention, and any structural, methodological, or functional modifications made by those skilled in the art based on these embodiments are included within the scope of protection of the present invention.

[0020] If the present invention involves orientation (e.g., up, down, left, right, front, back, outside, inside, etc.) when described, then the orientations involved need to be defined.

[0021] The scope of the embodiments described herein includes the entire scope of the claims and all available equivalents thereof. Throughout this document, the terms “first,” “second,” etc., are used only to distinguish one element from another without requiring or implying any actual relationship or order between the elements. Indeed, a first element can also be referred to as a second element, and vice versa. Furthermore, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a structure, apparatus, or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a structure, apparatus, or device. Without further limitations, an element defined by the phrase “comprising one…” does not exclude the presence of other identical elements in the structure, apparatus, or device that includes said element. The various embodiments described herein are presented in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably.

[0022] The terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer" used in this document to indicate orientation or positional relationships are based on the orientation or positional relationships shown in the accompanying drawings and are used only for the convenience of describing this document and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention. In the description herein, unless otherwise specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to mechanical or electrical connections, or internal connections between two elements, or direct connections or indirect connections through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms according to the specific circumstances.

[0023] The following is in conjunction with the appendix Figure 1 To be continued Figure 3 This invention provides a detailed description of a remote control system for a port container crane, as provided in an embodiment of the invention.

[0024] I. System Implementation Example: Remote Control System Based on Dynamic Sensing and Compensation The following is in conjunction with the appendix Figure 1 and attached Figure 2 The system composition and functional logic provided in this embodiment are described in detail. The core of the remote control system for port container cranes described in this invention lies in constructing a closed-loop architecture that can perceive the physical state of the machinery in real time and use this to guide the allocation of visual resources and command compensation.

[0025] This system mainly includes: a network monitoring module, a controller, a sensor group, a video encoder, and a remote operation terminal.

[0026] The sensor array is distributed across key components of the crane to acquire real-time operating parameters. Specifically, the sensor array includes an absolute encoder mounted on the hoisting mechanism to collect the real-time height of the spreader. The feedback unit installed on the frequency converter is used to monitor the current running speed of the trolley in real time. and the current lifting speed of the spreader In addition, the system is equipped with a laser rangefinder to accurately measure the distance between the center point of the spreader and the top surface of the target container. The system also pre-stores inherent parameters of the equipment, such as the rated maximum speed of the trolley. And dimensionless pixel statistics, such as the pixel area of ​​a whole frame of video. and core operating area pixel area .

[0027] The network monitoring module is integrated into the network communication link and is responsible for real-time monitoring of the total available network bandwidth. and network latency gradient These underlying network data are prerequisites for triggering the system's fault tolerance mechanism and dynamic adjustment logic.

[0028] The controller, serving as the system's decision-making core, incorporates dynamic bandwidth allocation logic. This controller is configured to calculate, in real-time, the allocation ratio coefficient for the core video task area based on pose and visual parameters fed back from the sensor array. The specific mathematical model is as follows:

[0029] In the above formula, This is the preset lower limit of the bandwidth ratio (with a value of 0.2). The upper limit is 0.95.

[0030] This upper limit ensures that even during the most precise container alignment phase, at least 5% of bandwidth resources are reserved for the non-interest area (background area). From a video coding stability perspective, mainstream coding protocols such as H.265 require a certain bitrate difference gradient between the region of interest (ROI) and the non-ROI. If the ratio factor approaches 1, causing the background bandwidth to drop to zero, the encoder's underlying logic will generate calculation errors due to a lack of contextual reference data, potentially leading to complete image loss or encoder crashes. From an intrinsic safety perspective, even during critical container alignment, operators still need to perceive the surrounding working environment through the edges of the screen. The mandatory reserved background bandwidth ensures that personnel, vehicles, or sudden obstacles in adjacent container positions can be detected in real time, avoiding safety blind spots caused by excessive focus on localized areas.

[0031] This lower limit ensures the necessary clarity and smoothness of the overall video feed when the crane is performing large-scale cross-regional transport tasks. When the trolley is moving at high speed or the spreader is in a high position, the background movement in the video feed is extremely rapid. If the bandwidth allocated to the background by the system is insufficient at this time (i.e.,...), the video feed will be affected. (If too high), it will cause severe pixelation and screen tearing in the overall background image. Setting it to 0.2 means that the system can allocate 80% of its bandwidth resources to the background area under high-speed conditions. This aligns with the physiological characteristics of operators who rely more on global situational awareness during long-distance transport, providing visual smoothness comparable to local operations.

[0032] Introducing constants and A physical boundary fence was constructed for the control system. In actual operating environments, physical parameters (such as distance) collected by sensors... or height The bitrate may approach zero due to occlusion or extreme positions. By forcibly constraining the allocation ratio within the range of [0.2, 0.95], the system can ensure that the core region will not exhaust the encoder's full bitrate resources, and the background region always has the most basic visualization conditions, regardless of fluctuations in external operating parameters. This defensive constraint significantly improves the fault tolerance of the solution under extreme conditions and ensures the industrial-grade robustness of the control system.

[0033] In the denominator of the above formula Defined as the operational potential energy term, it is used to measure the refresh rate of the background image. During the large-scale cross-section transport phase of the crane, due to the trolley speed... The height is high and the lifting device is in a high position. , The value of increases significantly. According to the formula structure, this increase will lead to... Towards the preset lower boundary (0.2) Approach. The underlying technical logic is that under high-speed motion conditions, the relative displacement of background objects is extremely fast. If high bandwidth resources are forcibly concentrated on a local region of interest, it will cause severe tearing and pixelation in the background area due to bandwidth shortage. Through this negative feedback adjustment, the system can automatically ensure the continuity of the global field of view, which meets the physiological needs of operators for environmental situational awareness when moving over a wide area.

[0034] The right side of the denominator in the formula Defined as a proximity perception term, it measures the urgency of target acquisition. Among these, the distance parameter... It is the core driving force; as the spreader descends and approaches the top of the target container, this value decreases rapidly, prompting... Towards the upper limit boundary (0.95) Approaching. Furthermore, the formula introduces the video pixel area ratio. As a pixel compensation factor, its physical meaning is to translate the proximity of the operation in the physical space into the precision requirements at the screen pixel level. When the core operation area occupies a relatively small portion of the screen, this factor increases, allowing the system to maintain attention to the overall background even when the spreader is far from the target; while when the spreader is actually in the final stage of aligning with the container, this factor decreases. The multiplicative effect disappears quickly, thus triggering the ultra-high-definition box-to-box mode.

[0035] In summary, this formula simulates the "attention allocation" mechanism of the human visual system in complex tasks. During the remote and high-speed movement phases of the operation, the system exhibits characteristics similar to "peripheral vision," prioritizing the smoothness of the overall view to reduce visual fatigue. In the precise operation phase involving the container, the system exhibits characteristics similar to "pupil focusing," automatically suppressing irrelevant background interference and concentrating 95% of network resources on the contact surface between the spreader and the container opening, thus ensuring the accuracy and inherent safety of remote control at the physical level.

[0036] The controller further integrates a command smoothing compensation module. This module is configured to smooth control commands... Break it down into the horizontal speed command of the car and lifting speed command For trolley mechanisms with significant mechanical inertia, the system monitors the command sequence in real time. and its cycle In the event of a network anomaly, a dedicated compensation mode for the vehicle is automatically triggered. The compensation logic first executes trend prediction:

[0037] This formula predicts the command value in the current cycle at the moment of network data loss or delay by superimposing the command value from the previous moment with its captured trend. This logic ensures the linear continuity of control commands on the time axis, effectively solving the problem of abrupt command drops caused by instantaneous network packet loss. In actual operation, the operator's operation of the remote handle is usually a smooth and physically continuous movement process, with its command flow exhibiting a clear inertial trend. This system captures the difference between preceding commands, essentially extracting the operator's operating rate before the current moment. By compensating for this rate in the lost current cycle, the system can highly restore the operator's true control intention, ensuring that the frequency control signal sent to the inverter has smooth derivative characteristics, thus achieving a smooth mapping of operator actions at the electrical drive level.

[0038] This system explicitly breaks down the overall control command into commands specific to the horizontal movement of the trolley. Commands for lifting motion of the spreader Lifting speed command for the lifting device Its feedback parameters play a dual core role in this system: firstly, at the perception and recognition level, the lifting speed... Distance from target Together, these constitute the proximity sensing term in the video bandwidth allocation model. When the lifting speed decreases and the spreader approaches the target, this parameter prompts the system to recognize that it is about to enter the critical stage of aligning with the container, thereby triggering the video allocation ratio coefficient. Approaching the maximum value provides ultra-high-definition visual feedback to the operator. Secondly, at the control isolation level, this dimensional separation achieves logical decoupling between longitudinal and horizontal motion. Because the trolley mechanism has significant mechanical inertia and is highly prone to swaying, this separation ensures the system's ability to respond to trolley commands... When performing complex trend prediction and amplitude limiting compensation, it will not interfere with the normal operation of the hoisting mechanism, ensuring the coordination and stability of the whole machine's movement.

[0039] To prevent the lifting device from swinging violently due to neglecting mechanical inertia in the predicted commands, the system incorporates a maximum permissible acceleration specific to the trolley mechanism. As a physical boundary constraint, a physical safety barrier is established. The command compensation module calculates the command periodically. Real-time calculation of the final output of the trolley instructions to the actuator Its logical calculation formula is as follows: like Then execute:

[0040] like Then execute:

[0041] in, This is a sign function. This logic ensures that, under network jitter conditions, the speed change of the trolley is always limited to the safe acceleration range that the mechanical structure can withstand, effectively eliminating the risk of secondary swaying of the spreader caused by a sudden increase in compensation commands.

[0042] The video encoder receives the values ​​calculated by the controller. and combined with the total available bandwidth The real-time video stream is encoded with ROI. The encoded stream is then transmitted back over the network to a remote control terminal for display.

[0043] II. System Operation Scenario Examples The following demonstration uses a specific application scenario to illustrate the system's operational logic and its resulting technical effects.

[0044] The following section provides a detailed explanation of the dynamic adjustment and compensation logic of the system described in this embodiment of the invention, using specific operational scenarios to demonstrate the system's technological advancements and physical consistency at different operational stages.

[0045] Scenario 1: Large-scale inter-regional displacement transportation stage. During the inter-regional transportation process when the crane is empty or fully loaded with the container, the system exhibits obvious high-position and high-speed dynamic characteristics.

[0046] The input parameters are set as follows: the current running speed of the car. The speed is 3.5 m / s, and the real-time height of the lifting device is [missing information]. The distance is 30 meters from the top of the target container. It is 40 meters.

[0047] Under this operating condition, due to the working potential energy term It plays a dominant role in the denominator of the calculation model and is the system's calculated region of interest allocation ratio coefficient. It will touch and remain at the preset lower limit boundary of 0.2.

[0048] The profound physical significance of this adjustment logic lies in the fact that when machinery is moving at high speed over long distances, the operator's primary need is to grasp the orientation of the spreader relative to the global environment, rather than focusing on minor local details.

[0049] The system effectively solves the problem of severe visual tearing and edge mosaic caused by rapid relative displacement of the background by dynamically allocating 80% of the bandwidth resources to areas of non-interest (i.e., the background image). This adaptive allocation of resource weights ensures that operators can obtain a smooth and consistent global monitoring view, thereby greatly reducing visual fatigue during large-scale transportation.

[0050] Scenario 2: Fine-tuning the container and network anomaly conditions. When the crane enters the final fine-tuning stage of container alignment, the vertical height of the spreader decreases and gradually approaches the top surface of the target container. The input parameters are set as follows: the distance from the center point of the spreader to the top surface of the target container. The real-time height of the lifting device is 0.1 meters. It is 1.0 meter.

[0051] As the weight of the proximity term in the formula decreases rapidly, the allocation ratio coefficient calculated by the system... The system quickly moves towards the preset upper limit boundary of 0.95. At this point, the system automatically executes a background bandwidth suppression strategy, concentrating 95% of network resources on the core alignment area between the spreader and the container opening, providing sub-centimeter-level ultra-high-definition visual feedback to the operator, ensuring the accuracy and success rate of the container alignment operation.

[0052] If, at this critical moment, the network monitoring module identifies the network latency gradient... In the event of a sudden increase or loss of control commands, the command compensation module will immediately and seamlessly intervene. The system first performs multi-dimensional trend prediction by analyzing the preceding command sequence to simulate the continuity trend of the operator's handle actions, thus avoiding abrupt disappearance of commands.

[0053] Subsequently, the calculated predicted command is subject to the maximum permissible acceleration of the trolley mechanism. The physical fence constraints. The final output execution instructions. By limiting the command change rate to a preset safe physical threshold, the trolley mechanism can maintain a controlled physical inertial trajectory even under extreme conditions of network instability. This completely eliminates secondary swinging of the spreader caused by command interruption or sudden jump, and ensures the safety and stability of mechanical operations during critical box-fitting moments from a physical perspective.

[0054] III. Computer-readable storage media and terminal embodiments The following is in conjunction with the appendix Figure 3 The electronic terminal and storage medium provided in this embodiment will be described.

[0055] The electronic terminal provided in this embodiment has a hardware structure including a processor, a memory, and a communication bus. The memory stores program instructions that implement the above-mentioned system functions.

[0056] When the processor executes program instructions, the system interacts with the sensor array via a communication bus, parsing pose parameters in real time and calling the built-in model for calculations. Simultaneously, the processor continuously monitors the link status through the network interface; upon detecting data loss or delay, it immediately retrieves the preceding instruction sequence from memory to perform linear trend prediction and physical limiting calculations. This integrated hardware and software architecture solidifies complex spatial dynamic constraints into real-time control outputs, achieving inherent safety in remote control.

[0057] This invention can be an apparatus, method, and / or computer program product. A computer program product may include a readable storage medium having computer-readable program instructions loaded thereon for causing a processor to implement various aspects of the invention.

[0058] Storage media can be tangible devices that hold and store instructions for use by instruction execution devices. Storage media can include, for example, electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination thereof. More specific examples (a non-exhaustive list) of readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination thereof.

[0059] It should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0060] The detailed descriptions listed above are merely specific descriptions of feasible embodiments of the present invention, and are not intended to limit the scope of protection of the present invention. All equivalent embodiments or modifications made without departing from the spirit of the present invention should be included within the scope of protection of the present invention.

Claims

1. A remote control system for a port container crane, characterized in that, include: The system includes a network monitoring module, a controller, a sensor group, a video encoder, and a remote operation terminal. The network monitoring module is used to monitor the real-time available total bandwidth and latency gradient of the network. The sensor group is used to acquire the real-time operating parameters of the crane. The system dynamically adjusts the bandwidth allocation ratio of the video region of interest based on the real-time available total bandwidth, latency gradient, and real-time operating parameters, and performs smooth compensation on the control commands. The real-time operation parameters include: real-time height of the spreader, current running speed of the trolley, rated maximum speed of the trolley, current lifting speed of the spreader, distance between the center point of the spreader and the top surface of the target box, pixel area of ​​the entire video frame, and pixel area of ​​the core operation area; The dynamic adjustment of the bandwidth allocation ratio of the video region of interest is specifically achieved by: using the real-time height of the lifting device, the current running speed of the trolley, the rated maximum speed of the trolley, the current lifting speed of the lifting device, the distance between the center point of the lifting device and the top surface of the target box, and the video pixel area ratio to calculate the real-time bandwidth allocation ratio coefficient of the core working area of ​​the video. The calculation of the real-time bandwidth allocation ratio coefficient of the core video operation area is specifically as follows: a mathematical model containing a negative feedback adjustment term and a positive feedback enhancement term is constructed. The negative feedback adjustment term is composed of the product of the current running speed of the trolley and the real-time height of the spreader, which is used to characterize the displacement characteristics during the large-scale transportation stage. The positive feedback enhancement term is composed of the sum of the rated maximum speed of the trolley and the current lifting speed of the spreader, the distance between the center point of the spreader and the top surface of the target box, and the ratio of video pixel area, which is used to characterize the proximity perception characteristics during the box operation stage. The real-time bandwidth allocation ratio coefficient is subject to physical boundary constraints, specifically: the bandwidth allocation ratio coefficient is forcibly constrained within a specific numerical range by a preset constant to ensure that the background area always retains the minimum bandwidth resources. The smooth compensation of the control commands mentioned above specifically involves: splitting the control commands into trolley horizontal speed commands and spreader lifting speed commands for different degrees of freedom of the mechanism, and performing special compensation logic for the trolley horizontal speed commands with mechanical inertia characteristics; The specific compensation logic for the horizontal speed command of the trolley with mechanical inertia characteristics is as follows: real-time monitoring of the trolley command sequence and command cycle; when network latency anomaly or command loss is detected, linear trend prediction is performed based on the command values ​​of multiple previous cycles to generate a predicted command; and physical boundary limiting is performed in combination with the maximum allowable acceleration of the trolley mechanism. The physical boundary limiting method, which combines the maximum permissible acceleration of the trolley mechanism, specifically involves: comparing the absolute value of the difference between the predicted command of the current cycle and the executed command of the previous cycle; if the difference does not exceed the product of the maximum permissible acceleration and the command cycle, then the predicted command is executed; if the difference exceeds the product of the maximum permissible acceleration and the command cycle, then the direction of motion is determined according to the sign function, and a safety increment determined by the maximum permissible acceleration is superimposed on the command of the previous cycle.

2. The remote control system for a port container crane according to claim 1, characterized in that, The system's modules employ a series feedback mechanism, specifically: the network monitoring module sends the monitored bandwidth and latency parameters to the bandwidth allocation module and the instruction compensation module; the bandwidth allocation module calculates the allocation ratio based on the crane's pose parameters and inputs it into the video encoder. The instruction compensation module calls the instruction sequence based on the delay status to perform amplitude limiting prediction, and then sends the processed execution instruction to the crane frequency converter.

3. The remote control system for a port container crane according to claim 2, characterized in that, The parameters called in the amplitude limiting prediction process are consistent with the pose parameters used in the bandwidth allocation process.

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