Automatic box placing control method, device and equipment applied to reach stacker and reach stacker

Abstract

The embodiment of the invention provides an automatic box placing control method, device and equipment applied to a reach stacker and the reach stacker. The method comprises the steps that firstly, when a lifting appliance and a container grabbed by the lifting appliance move to the position above a target position, the current position and the target position of the container are obtained according to a sensor; then, according to the current position and the target position, a first pose deviation of the container is determined; then, when any deviation value in the first pose deviations is larger than a first preset pose deviation threshold value, the lifting appliance is controlled to adjust the container based on a first control strategy; and finally, when any deviation value in the first pose deviations is smaller than or equal to a first preset pose deviation threshold value and larger than a second preset pose deviation threshold value, the lifting appliance is controlled to adjust the container based on a second control strategy. By means of the method, the hysteresis problem of a sensing and control system is effectively solved, and high-precision and high-stability control in the container placing process of the reach stacker is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to a container unloading control method, in particular to an automatic container unloading control method, device and equipment applied to a reach stacker and the reach stacker. BACKGROUND

[0002] The reach stacker is a large engineering mechanical equipment, mainly used for loading and unloading operations between railway open wagons and containers. In railway transportation, containers are usually transported by open wagons, and after arriving at the freight yard, the reach stacker needs to accurately take the container out of the open wagon and place it at the designated position (such as the ground or stacking). With the increasing demand for logistics automation, the automatic container unloading function of the reach stacker has become a key link to improve work efficiency and reduce manual intervention. This scenario puts high requirements on the control accuracy, stability and anti-interference ability of the equipment, especially when the spreader and the container move as a large mass, the system needs to overcome inertia, delay and other complex dynamic characteristics to ensure the high precision and safety of the container unloading process.

[0003] In the prior art, the commonly used automatic container unloading control method is to collect the pose information of the container and the target position in real time through sensors such as laser radar and vision camera, then calculate the moving trajectory of the spreader, and drive the hydraulic actuator (such as oil cylinder, valve) to adjust the position of the spreader to gradually align with the target position; and in the moving process of the spreader, the perception system continuously feeds back real-time data, and the control system dynamically corrects the control command according to the deviation until the container unloading operation is completed.

[0004] However, the existing scheme has the problems of calculation delay and inability to solve the container unloading error caused by inertia effect. SUMMARY

[0005] The embodiments of the present application provide an automatic container unloading control method, device and equipment applied to a reach stacker, to solve the problems of calculation delay and inability to solve the container unloading error caused by inertia effect in the prior art.

[0006] In a first aspect, the embodiments of the present application provide an automatic container unloading control method applied to a reach stacker, the reach stacker comprising a sensor and a spreader, comprising:

[0007] When the spreader and the container grasped thereby move above the target position, acquiring a current position of the container according to the sensor;

[0008] According to the current position and the target position, determining a first pose deviation of the container, wherein the pose deviation is the deviation of the current position of the container and the horizontal projection pose of the target position;

[0009] when any of the first pose deviation values is greater than a first preset pose deviation threshold, controlling the spreader to adjust the container based on a first control strategy;

[0010] when any of the first pose deviation values is less than or equal to the first preset pose deviation threshold and greater than a second preset pose deviation threshold, controlling the spreader to adjust the container based on a second control strategy, the second preset pose deviation threshold being less than the first preset pose deviation threshold.

[0011] In a possible implementation, the pose deviation includes a lateral dimension deviation, a longitudinal dimension deviation, and a rotation dimension deviation.

[0012] The controlling the spreader to adjust the container based on the first control strategy includes:

[0013] adjusting the lateral dimension deviation, the longitudinal dimension deviation, and the rotation dimension deviation in sequence by using a coarse control law;

[0014] obtaining a second pose deviation between a current position and a target position of the container after the adjustment;

[0015] if any of the second pose deviation values is greater than a preset pose deviation threshold, controlling the spreader to adjust the container by using the coarse control law again;

[0016] if all of the second pose deviation values are less than the preset pose deviation threshold, determining the second pose deviation as a new first pose deviation, and controlling the spreader to adjust the container based on the second control strategy.

[0017] In a possible implementation, the coarse control law includes:

[0018]

[0019] wherein, is a coarse control output, is a coarse proportionality coefficient, E is a current pose deviation to be adjusted, is a feedforward quantity based on deviation size and system characteristics, used to accelerate response.

[0020] In a possible implementation, the controlling the spreader to adjust the container based on the second control strategy includes:

[0021] taking a dimension with the largest deviation value in the first pose deviation as a target dimension;

[0022] continuously adjusting the target dimension within a preset time length action window by using a fine control law;

[0023] After the first preset time window ends, the output control quantity stops and the system enters a preset duration waiting window.

[0024] After the preset waiting window ends, the third pose deviation between the current position and the target position of the container after adjustment is obtained;

[0025] If the deviation value of any dimension of the third pose deviation is less than or equal to the second preset pose deviation threshold, then the spreader is controlled to perform a container placement operation.

[0026] If the deviation value of any dimension of the third pose deviation is greater than the second preset pose deviation threshold, then the third pose deviation is taken as the new first pose deviation, and the spreader is controlled to adjust the container based on the second control strategy.

[0027] In one possible implementation, the fine-tuning control law includes:

[0028]

[0029] in, To fine-tune the control output, To fine-tune the scaling factor, This refers to the deviation in the target dimension.

[0030] In one possible implementation, the method further includes:

[0031] When any of the first pose deviation values ​​is less than the second preset pose deviation threshold, the spreader is controlled to perform a container placement operation.

[0032] Secondly, embodiments of this application provide an automatic box-laying control device for a front-end crane, comprising:

[0033] The acquisition module is used to acquire the current position of the container based on the sensors when the spreader and the container it has grabbed move above the target position;

[0034] The determination module is used to determine the first pose deviation of the container based on the current position and the target position, wherein the pose deviation is the deviation of the projection pose of the current position and the target position of the container in the horizontal direction.

[0035] The first control module is used to control the spreader to adjust the container based on a first control strategy when any deviation value in the first pose deviation is greater than a first preset pose deviation threshold.

[0036] The second control module is configured to control the spreader to adjust the container based on a second control strategy when any of the first pose deviations is less than or equal to a first preset pose deviation threshold and greater than a second preset pose deviation threshold, and the second preset pose deviation threshold is less than the first preset pose deviation threshold.

[0037] In a possible implementation, the pose deviations include a lateral dimension deviation, a longitudinal dimension deviation, and a rotational dimension deviation.

[0038] The first control module is specifically configured to:

[0039] The lateral dimension deviation, the longitudinal dimension deviation, and the rotational dimension deviation are sequentially adjusted by using a coarse adjustment control law.

[0040] A second pose deviation between the current position and the target position of the container after the adjustment is obtained.

[0041] If any of the second pose deviations is greater than a preset pose deviation threshold, the spreader is controlled to use the coarse adjustment control law again to adjust the container.

[0042] If any of the second pose deviations is less than the preset pose deviation threshold, the second pose deviation is determined as a new first pose deviation, and the spreader is controlled to adjust the container based on the second control strategy.

[0043] In a possible implementation, the coarse adjustment control law includes:

[0044]

[0045] wherein, is a coarse adjustment control output, is a coarse adjustment proportionality coefficient, E is a current pose deviation to be adjusted, is a feedforward quantity based on a deviation size and system characteristics, and is used to accelerate response.

[0046] In a possible implementation, the second control module is specifically configured to:

[0047] A dimension with the largest deviation value in the first pose deviations is taken as a target dimension.

[0048] A fine adjustment control law is used to continuously adjust the target dimension within a preset time length action window.

[0049] After the first preset time window ends, the output of the control quantity is stopped and a preset time length waiting window is entered.

[0050] After the end of the preset time length waiting window, a third pose deviation between the current position and the target position of the container is obtained;

[0051] If the deviation value of any dimension in the third pose deviation is less than or equal to a second preset pose deviation threshold, the spread operation of the spreader on the container is controlled.

[0052] If the deviation value of any dimension in the third pose deviation is greater than the second preset pose deviation threshold, the third pose deviation is taken as a new first pose deviation, and the adjustment of the spreader on the container is controlled based on a second control strategy.

[0053] In a possible implementation, the fine adjustment control law comprises:

[0054]

[0055] wherein, is a fine adjustment control output, is a fine adjustment proportionality coefficient, is a target dimension deviation.

[0056] In a possible implementation, the second control module is further configured to:

[0057] When the deviation value of any dimension in the first pose deviation is less than the second preset pose deviation threshold, the spread operation of the spreader on the container is controlled.

[0058] In a third aspect, an embodiment of the present application provides an electronic device, comprising a memory and a processor.

[0059] The memory stores computer execution instructions.

[0060] The processor executes the computer execution instructions stored in the memory, so that the processor executes the first aspect and / or various possible implementations of the first aspect.

[0061] In a fourth aspect, an embodiment of the present application provides a computer readable storage medium, which stores computer execution instructions, and the computer execution instructions are executed by a processor to implement the first aspect and / or various possible implementations of the first aspect.

[0062] In a fifth aspect, an embodiment of the present application provides a reach stacker, comprising a sensor, a spreader, a memory and a processor.

[0063] The memory stores computer execution instructions.

[0064] The processor executes computer execution instructions stored in the memory, causing the processor to perform the first aspect and / or various possible implementations of the first aspect as described above.

[0065] The automatic container placement control method, device, equipment, and reach stacker provided in this application embodiment, after the spreader and container move above the target position, firstly, sensors installed on the reach stacker acquire the container's current position in real time and compare it with a pre-set target position to obtain the first positional deviation of the container in the lateral, longitudinal, and rotational directions. This positional deviation reflects the overall deviation state of the container in the horizontal direction and is the direct basis for subsequent control adjustments. Based on this, when the deviation value in any dimension exceeds a first preset positional deviation threshold, it indicates that there is still a significant positional and orientation difference between the container and the target position. At this time, a first control strategy is adopted to control the spreader. This strategy is a fast-response coarse adjustment method that quickly reduces the deviation with a large output without focusing on high precision, thereby efficiently pushing the container into the finely adjustable error range. Subsequently, when all dimensions of the first positional deviation no longer exceed the first threshold but are still greater than the second preset positional deviation threshold, it indicates that the container has entered the fine alignment area, and at this time, the second control strategy is switched. The second control strategy makes the adjustment process smoother by performing fine and stable small-amplitude corrections on the deviation, avoiding oscillations and overshoot. Through the above-mentioned progressive control process, large deviations can be quickly reduced first, and then fine-tuning can be completed in a high-precision manner, so as to achieve stable, reliable and high-precision placement of containers at the target position, thereby improving the efficiency and accuracy of the automated container placement process. Attached Figure Description

[0066] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0067] Figure 1 A flowchart illustrating the automatic container placement control method for a front-end crane provided in this application embodiment. Figure 1 ;

[0068] Figure 2 A flowchart illustrating the automatic container placement control method for a front-end crane provided in this application embodiment. Figure 2 ;

[0069] Figure 3 A schematic diagram of the horizontal projection of the relative pose of a container provided in an embodiment of this application;

[0070] Figure 4 This is a structural schematic diagram of an automatic box-laying control device for a front-mounted crane, provided in an embodiment of this application.

[0071] Figure 5A structural schematic diagram of an electronic device provided by an embodiment of the present application.

[0072] The specific embodiments of the present application have been shown through the above-described drawings, and will be described in more detail hereinafter. These drawings and the written description are not intended to restrict the scope of the present application by any means, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0073] Exemplary embodiments will be described in detail with reference to the drawings, of which examples are shown. In the following description, the same numbers are used to denote the same elements throughout the several drawings. The embodiments described in the following exemplary embodiments are not meant to represent all implementations consistent with the present application. Rather, they are merely examples of apparatus and methods consistent with some aspects of the present application as detailed in the appended claims.

[0074] A front loader is a large engineering machinery device, mainly used for loading and unloading operations between railway open wagons and containers. In railway transportation, containers are usually transported by open wagons, and after arriving at the freight yard, the front loader needs to accurately take the container out of the open wagon and place it at the designated position (such as the ground or stacking). With the increasing demand for logistics automation, the automatic container placing function of the front loader becomes a key link to improve operation efficiency and reduce manual intervention. This scenario puts forward very high requirements for the control accuracy, stability and anti-interference ability of the device, especially when the spreader and the container move as a large mass, the system needs to overcome inertia, delay and other complex dynamic characteristics to ensure the high precision and safety of the container placing process.

[0075] In the prior art, the commonly used automatic container placing control method is to collect the pose information of the container and the target position in real time through sensors such as laser radars and vision cameras, then calculate the moving trajectory of the spreader, and drive the hydraulic actuator (such as oil cylinder, valve) to adjust the position of the spreader to gradually align with the target position; and in the process of moving the spreader, the perception system continuously feeds back real-time data, and the control system dynamically corrects the control command according to the deviation until the container placing operation is completed.

[0076] However, in the existing scheme, due to the large mass of the joint of the spreader and the container, the inertia generated when the movement starts and stops is much larger than that in the empty state, resulting in overshoot and oscillation in the pose adjustment process.

[0077] Based on this, this application proposes an automatic container placement control method for reach stackers. Due to the massive mass of the spreader and container assembly, significant inertial effects occur during startup, braking, and small-amplitude position adjustments, making it difficult for the control system to achieve accurate response in a short time, often resulting in overshoot, repeated swinging, and oscillation. The inventors recognized that large-mass systems must employ a phased, precision-based, and control intensity-based approach in position adjustment to balance speed and stability. Therefore, a two-stage control principle is proposed, dividing the control process into coarse and fine adjustments. In specific implementation, firstly, after the spreader and the container it has grabbed reach above the target position, the current position of the container is obtained through sensors and compared with the target position to obtain the first positional deviation in the lateral, longitudinal, and rotational directions. When any deviation exceeds a first preset threshold, a first control strategy is used to perform coarse adjustment, rapidly reducing the large deviation with a large and fast control response, bringing the container into a range that can be precisely adjusted. Subsequently, when the deviation is no longer below the first threshold but still greater than a second preset threshold, the second control strategy is switched to precisely correct the remaining deviation through small, stable, and gradual fine adjustments, avoiding oscillations or overshoot caused by inertia. By employing this segmented control principle of first rapidly converging large deviations and then smoothly handling small deviations, this invention effectively overcomes the adverse effects of inertia under heavy load conditions, achieving the technical effects of rapid response, stable control, and significantly improved alignment accuracy during the pose adjustment process.

[0078] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with 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. The embodiments of this application will now be described with reference to the accompanying drawings.

[0079] Figure 1 A flowchart illustrating the automatic container placement control method for a front-end crane provided in this application embodiment. Figure 1 ;like Figure 1 As shown, the method includes:

[0080] S101. When the spreader and the container it grabs move above the target position, the current position of the container is obtained according to the sensor.

[0081] It should be understood that when the spreader and the container it grabs move to an area above the target location (e.g., within 0.5m of the target location), the control system activates the positioning and sensing module, which uses sensors such as laser rangefinders, vision cameras or millimeter-wave radar to collect the coordinate information of the container in the horizontal plane in real time, including the real-time position of the container center in the horizontal (X direction) and vertical (Y direction), as well as the rotation angle (θ) of the container relative to the ground coordinate system.

[0082] It can be understood that, by being able to obtain accurate position and attitude information in real time, high-precision input is provided for subsequent pose deviation calculation and control decision, thereby improving the overall accuracy and stability of the container.

[0083] S102, determining a first pose deviation of the container according to the current position and the target position.

[0084] The pose deviation is a deviation of the current position and the target position of the container in the horizontal direction projection pose, and the pose deviation includes a lateral dimension deviation, a longitudinal dimension deviation and a rotational dimension deviation.

[0085] It should be understood that in the present embodiment, after obtaining the current pose, the control system calculates the first pose deviation of the container in the horizontal direction projection plane according to the difference between the current position and the target position. The pose deviation includes a lateral dimension deviation ( ), a longitudinal dimension deviation ( ) and a rotational dimension deviation around the vertical axis direction ( ). The deviation calculation can use:

[0086]

[0087]

[0088]

[0089] The target position is ( ), and the current pose is ( ).

[0090] In an example, when the target position of the container is the center point of a specific slot in the yard, the system calculates the planar position of the current container according to the data recognized by the camera, thereby obtaining the deviation amount. The deviation represents the misalignment amount of the container relative to the target position, and is the basis for control strategy selection.

[0091] It can be understood that, by quantitatively expressing the pose deviation, the abstract spatial attitude can be converted into a controllable amount, so that the subsequent control process can be differentially processed according to different dimension deviations, thereby improving the adjustment efficiency.

[0092] S103, when any deviation value in the first pose deviation is greater than a first preset pose deviation threshold, controlling the spreader to adjust the container based on a first control strategy.

[0093] It should be understood that when any dimension (lateral, longitudinal, rotational) deviation value in the first pose deviation is greater than the first preset pose deviation threshold (for example, greater than 20 cm in lateral / longitudinal direction, greater than 5° in rotation), it is judged that the current alignment error is large, and the first control strategy is triggered at this time.

[0094] The first control strategy is generally a large-amplitude fast adjustment control, for example, through the spreader drive mechanism to make a correction with a high speed and a large control gain, so that the container quickly approaches the target position. In an implementable manner, the system adopts a coarse alignment gain matrix with a large proportional amplification coefficient, so that the spreader can quickly eliminate large deviations and achieve efficient correction. For example, if the lateral deviation of the container reaches 35 cm due to the inertia of the trolley, the coarse alignment mode is immediately entered, so that the spreader lateral trolley moves at a high speed to the target direction to quickly reduce the deviation to the range that can enter fine adjustment.

[0095] It can be understood that the overall alignment efficiency can be greatly improved through the coarse alignment strategy, and time waste caused by using small-amplitude and low-speed fine adjustment mode when the deviation is large can be avoided, so as to effectively shorten the adjustment time before the container is placed and improve the operation efficiency.

[0096] S104, when any deviation value in the first pose deviation is less than or equal to the first preset pose deviation threshold and greater than the second preset pose deviation threshold, the container is adjusted by the spreader based on the second control strategy.

[0097] The second preset pose deviation threshold is less than the first preset pose deviation threshold.

[0098] In an implementable manner, when any deviation value in the first pose deviation is less than the second preset pose deviation threshold, the container is placed by the spreader.

[0099] It should be understood that in another case, when any dimensional deviation value of the first pose deviation is less than or equal to the first preset pose deviation threshold but still greater than the second preset pose deviation threshold (for example, less than 20 cm but greater than 2 cm), the system judges that the deviation has entered the fine adjustment interval, and at this time, the second control strategy is used to continue to perform fine adjustment on the container. The second control strategy adopts a smaller control gain, a smoother speed curve and a higher frequency feedback control, so that the container can avoid overshoot and oscillation when approaching the target position, and high-precision positioning is achieved. For example, when the lateral deviation of the container is reduced to 9 cm and the rotation deviation is 1 degree after coarse alignment, the system automatically switches to the fine alignment mode to perform fine adjustment in a small step and multiple feedback manner, so as to ensure that the container can accurately align with the lock hole position.

[0100] It should be noted that when each dimensional deviation value in the first pose deviation is less than the second preset pose deviation threshold (for example, the deviation is less than 2 cm, and the angle deviation is less than 0.5 degrees), the control system considers that the container has completed alignment, and the spreader performs the container placing operation. The spreader is lowered and accurately places the container in the target box position or the slot.

[0101] It can be understood that by setting the threshold interval of two levels, the oscillation or overshoot caused by large gain can be avoided under the premise of ensuring the alignment speed, thereby improving the alignment accuracy. This mode realizes the balance between adjustment speed and stability, so that the error of the final box placement position is maintained in the range of millimeter to centimeter, which is of great significance to the safe operation of the automated yard.

[0102] The automatic box placing control method applied to the reach stacker provided by the embodiments of the present application first acquires the current position of the container in real time by using the sensor installed on the reach stacker after the spreader moves to the target position, and compares it with the target position set in advance, so as to obtain the first pose deviation of the container in the transverse direction, the longitudinal direction and the rotation direction. The pose deviation reflects the overall deviation state of the container in the horizontal direction, and is a direct basis for subsequent control adjustment. On this basis, when the deviation value in any dimension exceeds the first preset pose deviation threshold, it indicates that there is still a large position and attitude difference between the container and the target position. At this time, the first control strategy is used to control the spreader. This strategy is a fast-response coarse adjustment mode, which quickly reduces the deviation with a large output without paying attention to high precision, so as to efficiently push the container into the error range that can be finely adjusted. Then, when the dimensions of the first pose deviation are no longer greater than the first threshold but still greater than the second preset pose deviation threshold, it indicates that the container has entered the fine adjustment area. At this time, the second control strategy is switched. The second control strategy makes the adjustment process more smooth by making a careful and stable small correction to the deviation, avoiding oscillation and overshoot. Through the above layer-by-layer progressive control process, the large deviation can be quickly reduced first, and then fine adjustment can be completed in a high-precision manner, so as to realize stable, reliable and high-precision placement of the container on the target position, and improve the efficiency and precision of the automatic box placing process.

[0103] In an implementable manner, the specific manner of controlling the spreader to adjust the container based on the first control strategy includes:

[0104] First, the coarse adjustment control law is used to adjust the transverse dimension deviation, the longitudinal dimension deviation and the rotation dimension deviation in sequence. Then, the second pose deviation of the current position of the adjusted container and the target position is acquired. If any deviation value of the second pose deviation is greater than the preset pose deviation threshold, the spreader is controlled to use the coarse adjustment control law again to adjust the container. If any deviation value of the second pose deviation is less than the preset pose deviation threshold, the second pose deviation is determined as the new first pose deviation, and the spreader is controlled to adjust the container based on the second control strategy.

[0105] It should be noted that the specific control manner of the coarse adjustment control law is:

[0106]

[0107] In the above control process, the first pose deviation is the deviation of the container in the horizontal direction, and the second pose deviation is the deviation of the container in the vertical direction. is a coarse tuning control output, is a coarse tuning proportional coefficient, E is a current pose deviation to be adjusted, is a feedforward quantity based on the deviation size and system characteristics, used to accelerate the response.

[0108] It should be understood that when any of the first pose deviation values is greater than the first preset pose deviation threshold, the system initiates the coarse tuning control strategy to quickly correct the deviation of the container. Specifically, the spreader controller first performs independent closed-loop adjustment on the transverse dimension deviation, the longitudinal dimension deviation, and the rotation dimension deviation in turn according to the predetermined coarse tuning sequence; when adjusting each dimension, the system generates a corresponding control output based on the coarse tuning control law, thereby driving the spreader to move in a direction that reduces the deviation. By performing coarse tuning adjustment in a dimension-by-dimension and sequence-by-sequence manner, control interference caused by multi-dimensional coupled adjustment can be effectively avoided, and the stability and adjustment efficiency of the coarse tuning stage can be improved.

[0109] When adjusting using the coarse tuning control law, the system has basic correction ability through proportional adjustment, and uses the feedforward quantity to provide additional driving force for the spreader in advance, so that the system can quickly approach the target area when the deviation is large. Therefore, the control law has the advantages of fast response and high convergence speed in the large deviation scenario.

[0110] After completing a coarse tuning process, the controller obtains the updated current position of the container and calculates the second pose deviation between the current position and the target position. If any of the second pose deviation values is still greater than the preset pose deviation threshold, it indicates that the current coarse tuning has not eliminated the significant deviation, and the system will automatically trigger a new round of coarse tuning and perform coarse tuning correction in the transverse, longitudinal, and rotation dimension sequence again. The repeated coarse tuning design ensures that when the initial deviation of the container is large or affected by external disturbances (such as wind load), the system can still gradually approach the fine tuning area, thereby ensuring that the subsequent fine tuning stage has good initial conditions and improving the overall positioning efficiency and reliability.

[0111] Further, in the present embodiment, when each of the second pose deviation values is less than the preset pose deviation threshold, the system determines the second pose deviation as the new first pose deviation and automatically switches from the coarse tuning stage to the fine tuning stage based on the second control strategy. Through this connection method, the coarse tuning stage is only responsible for large-scale and fast error convergence, and the fine tuning stage is responsible for small-scale and high-precision final positioning, thereby forming a two-stage control structure from coarse tuning to fine tuning. This structure not only improves the overall positioning efficiency, but also avoids the problems of slow response and oscillation caused by using fine tuning control in a large deviation condition, further ensuring the safety and accuracy of the container depositing operation.

[0112] Figure 2Flowchart of the automatic box placing control method applied to the reach stacker provided by the embodiment of the present application Figure 2 As shown in Figure 1 the embodiment, on the basis of the embodiment, the process of adjusting the container by using the second control strategy is described in detail, and the method comprises the following steps: Figure 3

[0113] S201. Take the dimension with the maximum deviation value in the first pose deviation as the target dimension.

[0114] It should be understood that in the present embodiment, when the system enters the second control strategy, the controller first compares the lateral dimension deviation, the longitudinal dimension deviation and the rotation dimension deviation in the current first pose deviation to determine the dimension with the maximum deviation value as the target dimension for this adjustment. By selecting the maximum deviation dimension for priority adjustment, the system can concentrate the fine adjustment resources to the direction with the most prominent error, thereby effectively improving the overall correction efficiency and avoiding the problems of coupling effect and increased control complexity caused by multi-dimensional simultaneous control.

[0115] S202. Adopt the fine adjustment control law to continuously adjust the target dimension within a preset time length action window.

[0116] It should be noted that the specific control mode of the fine adjustment control law is as follows:

[0117]

[0118] Among them, is the fine adjustment control output, is the fine adjustment proportional coefficient, is the deviation of the target dimension.

[0119] It should be understood that after the target dimension is determined, the target dimension is continuously adjusted based on the fine adjustment control law. In the present embodiment, the fine adjustment control law can adopt the form of small proportional gain combined with damping compensation, which is used to realize smooth, small amplitude and high precision correction output. And the fine adjustment control law continuously outputs the fine adjustment control quantity to the actuator within the preset action time window, so that the spreader slowly approaches the target dimension in a slow adjustment manner. This method can effectively avoid the vibration, overshoot and swing phenomenon caused by large adjustment, and ensure that the container still has good stability when approaching the final target position.

[0120] S203. After the first preset time window ends, stop outputting the control quantity and enter a preset time length waiting window.

[0121] ​It should be understood that the setting of the waiting window is based on the fact that the spreader-container system often has certain inertial movement and slight swing after completing the fine adjustment action. In order to avoid the accumulation of measurement deviation caused by the measurement of the position and posture before the system is completely stable, the application sets a preset time length of the waiting window after the fine adjustment control output is terminated, so that the container completes the vibration damping and attitude stabilization through its own damping characteristics within the window. That is, the waiting window can ensure that the next collected position and posture data is in a relatively stable state, thereby improving the accuracy of subsequent deviation judgment, avoiding misjudgment of the control command due to dynamic fluctuations, and further improving the stability and control accuracy of the entire fine adjustment process.

[0122] S204, after the end of the preset time length of the waiting window, a third position and posture deviation between the current position and the target position of the adjusted container is obtained.

[0123] It should be understood that the third position and posture deviation is obtained after completing the fine adjustment action and experiencing the stable time of the waiting window, and reflects the attitude deviation of the container in the stable state after the inertia damping and swing are basically eliminated. Since the waiting window can effectively reduce the influence of dynamic disturbance, the third position and posture deviation is closer to the true steady-state error of the system than the instantaneous deviation at the end of the action window, so that the controller can make subsequent control strategy selection and container release determination based on stable and reliable deviation information.

[0124] It can be understood that, in order to ensure the measurement accuracy of the third position and posture deviation, the transverse position, longitudinal position and rotation angle of the container can be obtained by using a laser ranging sensor, a visual positioning system or a multi-sensor fusion method, and the measurement data can be denoised by combining a filtering algorithm (such as Kalman filtering) when necessary. Therefore, the third position and posture deviation not only reflects the latest stable state of the container attitude, but also provides a high-credibility input parameter for the next control cycle, so that the system can decide whether to enter the container release stage or continue to execute the fine adjustment control according to the deviation size.

[0125] S205, if the deviation value of any dimension in the third position and posture deviation is less than or equal to a second preset position and posture deviation threshold, the spreader releases the container.

[0126] It should be understood that the second preset position and posture deviation threshold is used to limit the final alignment accuracy required by the container before release, and its value is usually determined according to the structural characteristics of the yard crane or the rail-mounted crane, the tolerance range of the container position limiting structure, and the operation safety specification. When the transverse deviation, longitudinal deviation and rotation deviation in the third position and posture deviation do not exceed the threshold, it means that the container has been accurately aligned with the target container position and will not collide with or be blocked by the container slot, corner piece or surrounding structure during the release process. Therefore, the system can directly enter the release operation, thereby ensuring the safety and accuracy of the operation process.

[0127] It can be understood that, in actual application, to further improve the stability of the container placing, the controller can optionally perform a secondary confirmation action after determining that the container placing condition is met, for example, collecting multiple groups of pose data in a short time again, and ensuring that the third pose deviation is a stable error rather than a transient change through mean filtering or credibility evaluation. In addition, the container placing operation can include processes such as slowly lowering the spreader, accurately positioning, and releasing the container lock head. Through the above design, it can be ensured that the safe and smooth container placing action is completed under the premise of meeting the high-precision alignment requirement, thereby improving the reliability of the overall automated operation.

[0128] S206, if the deviation value of any dimension in the third pose deviation is greater than the second preset pose deviation threshold, the third pose deviation is taken as a new first pose deviation, and the spreader is controlled to adjust the container based on the second control strategy.

[0129] When the lateral deviation, longitudinal deviation, or rotational deviation in the third pose deviation in any dimension still exceeds the second preset pose deviation threshold, it indicates that the container has not yet reached the fine adjustment accuracy required for container placing, and direct container placing may cause interference between the container and the container position limiting structure. Therefore, the third pose deviation is redefined as a new first pose deviation, so that the system can continue to perform fine adjustment control based on the latest and stable converged deviation information in the waiting window, thereby ensuring the accuracy and stability of subsequent position adjustment.

[0130] It can be understood that, in the new round of fine adjustment process, the controller will still perform the closed-loop control process of target dimension selection, action window adjustment, waiting window stabilization, and deviation update based on the second control strategy. With this cyclic iteration structure, the pose deviation will gradually converge in the continuous action window and waiting window, so that the system can still maintain high-precision adjustment capability in the presence of external disturbances such as wind, slight swinging, or mechanical clearance. In this way, the spreader can approach the target position multiple times without oscillation, thereby significantly improving the overall automated calibration efficiency and the reliability of the final container placing positioning.

[0131] Figure 3 A schematic diagram of the horizontal projection of the relative pose of the container provided by the embodiments of the present application is shown in FIG. 1. As shown in FIG. 1, the dashed rectangle represents the target pose of the container (the reference pose aligned with the X and Y axes of the ground coordinate system), and the solid rotating rectangle represents the current pose of the container after being grabbed by the spreader. The origin A of the coordinate system is the reference point of the target position (i.e., the center point of the target position), and B Figure 4 (i.e., the center point of the current position of the container) is the current position and orientation of the container in the horizontal plane. The first pose deviation is the three-component deviation in the horizontal plane projection: ​​​(through A, B positions and When the spreader and the container it is holding move above the target position, the controller reads the position from the sensor as B, and compares the three components with two thresholds respectively: if any deviation component is greater than a first preset pose deviation threshold (indicating a larger position / orientation error), a first control strategy (coarse adjustment strategy - larger amplitude, fast pose correction to eliminate obvious deviation) is triggered; if any component is less than or equal to the first threshold but greater than a second preset threshold (indicating that the error has been greatly reduced but still needs to be fine-tuned), a second control strategy (fine adjustment strategy - small amplitude, low speed, closed loop fine adjustment) is triggered; when all three components are less than or equal to the second threshold, it is considered that the pose accuracy requirement has been met, and no further adjustment is needed, and the spreader can be directly controlled to perform the container dropping operation.

[0132] Figure 4 A structural schematic diagram of an automatic container dropping control device applied to a reach stacker is provided for the embodiments of the present application; as shown in the figure, the device comprises: Figure 5

[0133] The acquisition module 401 is configured to acquire the current position of the container according to the sensor when the spreader and the container it is holding move above the target position.

[0134] The determination module 402 is configured to determine a first pose deviation of the container according to the current position and the target position, wherein the pose deviation is the deviation of the current position of the container from the horizontal direction projection pose of the target position.

[0135] The first control module 403 is configured to control the spreader to adjust the container based on a first control strategy when any deviation value in the first pose deviation is greater than a first preset pose deviation threshold.

[0136] The second control module 404 is configured to control the spreader to adjust the container based on a second control strategy when any deviation value in the first pose deviation is less than or equal to the first preset pose deviation threshold and greater than a second preset pose deviation threshold, and the second preset pose deviation threshold is less than the first preset pose deviation threshold.

[0137] In a possible implementation, the pose deviation includes a lateral dimension deviation, a longitudinal dimension deviation, and a rotational dimension deviation.

[0138] The first control module 403 is specifically configured to:

[0139] adopt a coarse control law to sequentially adjust the lateral dimension deviation, the longitudinal dimension deviation, and the rotational dimension deviation;

[0140] acquire a second pose deviation of the current position of the adjusted container and the target position;

[0141] ​If any of the second pose deviation values is greater than the preset pose deviation threshold, the spreader is controlled to readopt the coarse control law to adjust the container.

[0142] If all of the second pose deviation values are less than the preset pose deviation threshold, the second pose deviation is determined as a new first pose deviation, and the spreader is controlled to adjust the container based on the second control strategy.

[0143] In a possible implementation, the coarse control law comprises:

[0144]

[0145] wherein, is a coarse control output, is a coarse proportional coefficient, and E is a current pose deviation to be adjusted, is a feedforward quantity based on the deviation size and system characteristics, and is used to accelerate the response.

[0146] In a possible implementation, the second control module 404 is specifically configured to:

[0147] take the dimension with the largest deviation value in the first pose deviation as a target dimension;

[0148] adopt a fine control law to continuously adjust the target dimension within a preset time length action window;

[0149] after the first preset time window ends, stop outputting the control quantity and enter a preset time length waiting window;

[0150] after the preset time length waiting window ends, obtain a third pose deviation between the current position and the target position of the adjusted container;

[0151] if the deviation value of any dimension in the third pose deviation is less than or equal to a second preset pose deviation threshold, the spreader is controlled to perform a container placing operation on the container;

[0152] if the deviation value of any dimension in the third pose deviation is greater than the second preset pose deviation threshold, the third pose deviation is taken as a new first pose deviation, and the spreader is controlled to adjust the container based on the second control strategy.

[0153] In a possible implementation, the fine control law comprises:

[0154]

[0155] wherein, is a fine control output, is a fine proportional coefficient, is a deviation of the target dimension.

[0156] In a possible implementation, the second control module 404 is further configured to:

[0157] When any of the first pose deviation values is less than the second preset pose deviation threshold, the spreader is controlled to perform a container placing operation on the container.

[0158] The automatic container placing control device applied to the reach stacker provided in the embodiments of the present application can execute the method provided in the method embodiments, and has similar implementation principles and technical effects. Details are not described herein again.

[0159] Figure 5 A structural schematic diagram of an electronic device provided in the embodiments of the present application is shown in FIG. 5. As shown in the figure, the electronic device 50 provided in the embodiments of the present application includes at least one processor 501 and a memory 502. Optionally, the device 50 further includes a communication component 503. The processor 501, the memory 502 and the communication component 503 are connected through a bus 505. ​

[0160] In the implementation process, the at least one processor 501 executes the computer execution instructions stored in the memory 502, so that the at least one processor 501 executes the method described above.

[0161] The specific implementation process of the processor 501 can refer to the method embodiments described above, and has similar implementation principles and technical effects. Details are not described herein again.

[0162] In the embodiments described above, it should be understood that the processor can be a central processing unit (CPU), and can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC) and the like. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor and the like. The steps of the method disclosed in the embodiments of the present application can be directly embodied as execution completed by a hardware processor, or executed by a combination of hardware and software modules in the processor.

[0163] The memory can include a random access memory (RAM), and can also include a non-volatile memory (NVM), for example, at least one disk memory.

[0164] ​The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, the bus in the drawings of the present application does not limit to only one bus or one type of bus.

[0165] The embodiment of the present application provides a front-end crane, including a sensor, a spreader and the electronic device.

[0166] The present application also provides a computer readable storage medium, and the computer readable storage medium stores computer execution instructions, and when a processor executes the computer execution instructions, the method described above is realized.

[0167] The readable storage medium described above can be realized by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk. The readable storage medium can be any available medium that can be accessed by a general-purpose or special-purpose computer.

[0168] An exemplary readable storage medium is coupled to the processor, so that the processor can read information from the readable storage medium, and can write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can be located in an application specific integrated circuit (ASIC). Of course, the processor and the readable storage medium can also exist in the device as discrete components.

[0169] The division of units is only a logical function division, and when actually implemented, there can be another division mode, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some interfaces, devices or units, and can be electrical, mechanical or other forms.

[0170] The units described as separate components may or may not be physically separate, and the components displayed as units may or may not be physical units, i.e., may be located in one place, or may be distributed to multiple network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment scheme.

[0171] In addition, each functional unit in various embodiments of the application can be integrated into one processing unit, or each unit can exist physically, or two or more units can be integrated into one unit.

[0172] If the function is realized in the form of a software function unit and sold or used as an independent product, it can be stored in a computer readable storage medium. Based on this understanding, the technical solutions of the application essentially or the part that contributes to the prior art or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the various embodiment methods of the application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a magnetic disk or an optical disk, and various media that can store program codes.

[0173] Those skilled in the art can understand that all or part of the steps of the above-mentioned method embodiments can be completed by program instruction related hardware. The aforementioned program can be stored in a computer readable storage medium. The program executes to perform the steps of the above-mentioned method embodiments; and the aforementioned storage medium includes: ROM, RAM, magnetic disk or optical disk, and various media that can store program codes.

[0174] Finally, it should be noted that those skilled in the art, after considering the specification and practicing the application disclosed herein, will easily think of other embodiments of the application. The application is intended to cover any variations, uses, or adaptations of the application that follow the general principles of the application and include common knowledge or conventional technical means in the art that are not disclosed by the application, and is not limited to the precise structure described above and shown in the drawings, and various modifications and changes can be made without departing from the scope thereof. The scope of the application is only limited by the appended claims.

Claims

1. An automatic box placing control method applied to a reach stacker, the reach stacker including a sensor and a spreader, characterized by, include: When the spreader and the container it has grabbed move above the target location, the current position of the container is obtained according to the sensor. Based on the current position and the target position, the first pose deviation of the container is determined, wherein the pose deviation is the deviation of the projection pose of the current position and the target position of the container in the horizontal direction. When any of the first pose deviations is greater than the first preset pose deviation threshold, the spreader is controlled to adjust the container based on the first control strategy; When any deviation value in the first pose deviation is less than or equal to the first preset pose deviation threshold and greater than the second preset pose deviation threshold, the spreader is controlled to adjust the container based on the second control strategy, wherein the second preset pose deviation threshold is less than the first preset pose deviation threshold.

2. The method of claim 1, wherein, The pose deviation includes lateral dimension deviation, longitudinal dimension deviation, and rotational dimension deviation; The step of controlling the spreader to adjust the container based on the first control strategy includes: A coarse-adjustment control law is used to adjust the horizontal dimension deviation, the vertical dimension deviation, and the rotational dimension deviation in sequence. Obtain the second pose deviation between the current position and the target position of the adjusted container; If any deviation value of the second pose deviation is greater than the preset pose deviation threshold, the spreader is controlled to re-adjust the coarse adjustment control law to adjust the container. If any deviation value of the second pose deviation is less than the preset pose deviation threshold, the second pose deviation is determined as the new first pose deviation, and the spreader is controlled to adjust the container based on the second control strategy.

3. The method of claim 2, wherein, The coarse adjustment control law includes: wherein, is a coarse control output quantity, is a coarse control proportional coefficient, E is a current pose deviation to be adjusted, is a feedforward quantity based on the deviation size and system characteristics, used to accelerate the response.

4. The method according to claim 1 or 2, characterized in that, The second control strategy controls the spreader to adjust the container, including: The dimension with the largest deviation value in the first pose deviation is taken as the target dimension; A fine-tuning control law is used to continuously adjust the target dimension within a preset duration action window; After the first preset time window ends, the output control quantity stops and the system enters a preset duration waiting window. After the preset waiting window ends, the third pose deviation between the current position and the target position of the container after adjustment is obtained; If the deviation value of any dimension of the third pose deviation is less than or equal to the second preset pose deviation threshold, then the spreader is controlled to perform a container placement operation. If the deviation value of any dimension of the third pose deviation is greater than the second preset pose deviation threshold, then the third pose deviation is taken as the new first pose deviation, and the spreader is controlled to adjust the container based on the second control strategy.

5. The method of claim 4, wherein, The fine-tuning control law includes: wherein, is a fine tuning control output quantity, is a fine tuning proportionality coefficient, is a deviation of the target dimension.

6. The method of claim 1, wherein, The method further includes: When any of the first positional deviations is less than the second preset positional deviation threshold, the spreader is controlled to perform a container placement operation.

7. An automatic box placing control device for a reach stacker, characterized by comprising: include: The acquisition module is used to acquire the current position of the container based on the sensors when the spreader and the container it has grabbed move above the target position; determining a first pose deviation of the container according to the current position and the target position, wherein the pose deviation is a deviation of the current position of the container from a horizontal direction projection pose of the target position; a first control module configured to control the spreader to adjust the container based on a first control strategy when any of the first pose deviations is greater than a first preset pose deviation threshold value; a second control module configured to control the spreader to adjust the container based on a second control strategy when any of the first pose deviations is less than or equal to the first preset pose deviation threshold value and greater than a second preset pose deviation threshold value, the second preset pose deviation threshold value being less than the first preset pose deviation threshold value.

8. An electronic device, comprising: comprising: a memory, a processor; the memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory, so that the processor executes the method of any one of claims 1-6.

9. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, and the computer-executable instructions are executed by the processor to implement the method of any one of claims 1-6.

10. A reach stacker, characterized in that The front-end crane comprises a sensor, a spreader, a memory and a processor; the memory stores computer-executable instructions; the processor executes the computer-executable instructions stored in the memory, so that the processor executes the method of any one of claims 1-6.

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