A method and control system for adaptive adjustment of clamping force for carton clamps

Abstract

The present application relates to the technical field of clamping control, in particular to a clamping force self-adaptive adjusting method and control system for a carton clamp, wherein, in the present application, dynamic mechanical characteristic parameters in the clamping and moving process of the carton clamp are acquired first, then the clamping process is divided into stages according to the parameters, and the compensation adjusting input is determined in combination with the clamping force error change in different stages, so that the clamping force adjustment can change synchronously with the advancement of the clamping process, and is no longer limited to the detection result at a single moment. Further, the present application introduces the adjustment for the current error state in the clamping establishment stage, and the input quantity is continuously corrected in combination with the current state in the stable clamping stage, so that the adjusting process of the clamping force can maintain higher consistency with the actual running stage of the carton clamp, and the output action control signal can be more consistent with the current clamping state.

Description

Technical Field

[0001] This invention relates to the field of clamping control technology, and in particular to an adaptive adjustment method and control system for clamping force of carton clamps. Background Technology

[0002] The field of clamping control technology involves the adjustment and management of the force applied by various clamping devices during operation. It mainly includes the acquisition of clamping force, feedback adjustment, and control of actuators. Its core purpose is to ensure that the clamped object is in a stable state during handling or processing.

[0003] Among them, the adaptive adjustment method of clamping force for carton clamps refers to a method of adjusting and controlling the clamping force applied to the carton by the clamping mechanism during the carton handling process. It usually involves sensing the clamping state and adjusting the actuator in combination with the control strategy to manage the carton clamping process.

[0004] Traditional carton clamping force adjustment methods, while capable of controlling the clamping action through sensor detection, often only adjust based on a single moment in the continuous process of the clamp gradually approaching the goods, making contact, and finally clamping. This results in insufficient differentiation between clamping stages. Since the clamp arm's movement and force changes differ at different stages, a uniform adjustment method can easily lead to inaccurate intervention timing at the initial contact with the carton, and insufficiently detailed adjustment criteria as the clamping stabilizes. Consequently, there is a lack of correlation between the clamping force changes and the actual state of the carton clamp. Furthermore, when carton specifications, materials, and loading conditions change, this adjustment method can also result in insufficient continuity of clamping action, making the transition between the initial contact stage and the subsequent stable clamping stage less smooth. Summary of the Invention

[0005] To address the technical problems existing in the prior art, embodiments of the present invention provide an adaptive adjustment method for clamping force of a carton clamp, comprising the following steps: To achieve the above objectives, the present invention adopts the following technical solution: a method for adaptive adjustment of clamping force for carton clamps, comprising the following steps: S1: Obtain the set of dynamic mechanical characteristic parameters of the forklift carton clamp during the clamping and moving process; S2: Based on the set of dynamic mechanical characteristic parameters, divide the operation stages of the carton clamp during the clamping and moving process, and generate segmented contact state identifiers; S3: When the clamp moves to the segmented contact state specified in the segmented contact state identifier, calculate the current carton clamping force error, and determine the sliding variable state of the sliding surface by combining the preset sliding form ratio adjustment coefficient. S4: Set the compensation adjustment input voltage of the carton clamp according to the segmented contact state identifier and the state symbol of the sliding variable state of the sliding surface; S5: Generate a carton clamp action control signal based on the compensated and adjusted input voltage, and output a carton clamp clamping force adaptive adjustment command.

[0006] As a further aspect of the present invention, the set of dynamic mechanical characteristic parameters includes carton clamping displacement characteristics, carton clamping speed characteristics, and carton clamping contact force characteristics; the segmented contact state identifiers include carton clamping approach contact stage identifiers, carton clamping contact establishment stage identifiers, and carton clamping stable clamping stage identifiers; the sliding surface sliding variable state is specifically a state value calculated by the current carton clamping force error and the sliding surface proportional adjustment coefficient; the compensation adjustment input voltage is specifically a voltage value calculated by the state symbols of the segmented contact state identifiers and the sliding surface sliding variable state; and the carton clamping force adaptive adjustment command includes a carton clamping action control signal.

[0007] As a further aspect of the present invention, step S1 specifically comprises: S101: Set the initial proportional overflow valve pressure of the forklift oil valve. During the continuous closing and clamping movement of the carton clamp towards the middle, acquire the current sampling time record of the carton clamp and the previous time record of the carton clamp. Collect the first analog voltage signal of the carton clamp displacement output by the displacement sensor and the second analog voltage signal of the carton clamp force output by the force sensor on the carton clamp clamping mechanism. Use an analog-to-digital converter to convert the first analog voltage signal of the carton clamp displacement into the current carton clamp clamping displacement and the second analog voltage signal of the carton clamp force into the current carton clamp contact force. S102: Calculate the time deviation between the current cardboard clamp sampling time record and the previous cardboard clamp advance time record to obtain the cardboard clamp sampling time deviation. Calculate the deviation between the current cardboard clamp holding displacement and the previous cardboard clamp advance displacement to obtain the cardboard clamp displacement change difference. Calculate the ratio of the cardboard clamp displacement change difference to the cardboard clamp sampling time deviation to obtain the current cardboard clamp holding displacement change rate. Calculate the deviation between the current cardboard clamp holding displacement change rate and the previous cardboard clamp advance displacement change rate to obtain the cardboard clamp velocity change difference. Calculate the ratio of the cardboard clamp velocity change difference to the cardboard clamp sampling time deviation to obtain the cardboard clamp holding displacement acceleration value. S103: Obtain the previous carton clamp's front force corresponding to the current carton clamp contact force, calculate the deviation between the current carton clamp contact force and the previous carton clamp's front force, obtain the carton clamp contact force change difference value, and combine it with the carton clamp contact force, the carton clamp clamping displacement change rate, and the carton clamp clamping displacement acceleration value to obtain a set of dynamic mechanical characteristic parameters.

[0008] As a further aspect of the present invention, step S2 specifically comprises: S201: Based on the set of dynamic mechanical characteristic parameters, collect the average value of the historical carton clamping acceleration when items touch each other during multiple historical carton clamp handling cycles, and configure the average value of the historical carton clamping acceleration as the acceleration threshold for determining carton clamp contact at the stage boundary and the acceleration threshold for determining carton clamp clamping, respectively, and establish a set of carton clamp stage division determination thresholds; S202: Based on the set of judgment thresholds for the carton clamp stage, compare the current carton clamp contact force, the current carton clamp displacement change rate, the carton clamp displacement acceleration value, and the carton clamp contact force change difference value with preset carton clamp contact force judgment thresholds, preset carton clamp displacement change rate judgment thresholds, carton clamp contact judgment acceleration thresholds, carton clamp clamping judgment acceleration thresholds, and preset carton clamp force change thresholds to determine the current operating stage state of the carton clamp; S203: Generate segment contact status identifiers based on the current operating stage status of the carton clamp.

[0009] As a further aspect of the present invention, step S3 specifically comprises: S301: When the segmented contact status indicator indicates that the current state has entered the carton clamp contact establishment stage, start the set pause timer, obtain the set carton clamp target clamping force, calculate the carton clamp force deviation between the set carton clamp target clamping force and the carton clamp contact force at the current moment, and obtain the carton clamp clamping force error. S302: Calculate the deviation between the current carton clamping force error and the previous carton clamping error to obtain the carton clamping error difference value. Calculate the ratio of the carton clamping error difference value to the preset carton clamping time interval to obtain the carton clamping force error change rate. S303: Set the sliding mode ratio adjustment coefficient, calculate the product of the carton clamping force error and the set sliding mode ratio adjustment coefficient to obtain the carton clamp ratio adjustment error, calculate the carton clamp control algebraic sum between the carton clamp ratio adjustment error and the carton clamping force error change rate, and establish the sliding variable state of the sliding mode surface.

[0010] As a further aspect of the present invention, step S4 specifically comprises: S401: Based on the segmented contact state identifier, the initial reference value of the carton clamp, the first safety gain value of the carton clamp against impact, and the second safety gain value of the carton clamp against disturbance are respectively matched for the carton clamp approach contact stage, the carton clamp contact establishment stage, and the carton clamp stable clamping stage, as sliding mode control gain parameters. S402: Before the segmented contact state indicator indicates that the carton clamp has entered the stable clamping stage, calculate the product between the initial proportional overflow valve pressure and the preset percentage increment to obtain the proportional overflow valve pressure supplement amount, obtain the preset oil valve pressure-voltage conversion coefficient, and calculate the product between the proportional overflow valve pressure supplement amount and the preset oil valve pressure-voltage conversion coefficient to obtain the carton clamp basic feedforward voltage amount. S403: Convert the sliding variable state of the sliding surface into corresponding positive and negative sign values, calculate the product of the positive and negative sign values, the sliding control gain parameter, and the equivalent coefficient of the preset carton clamping mechanism entity transfer relationship to obtain the carton clamp feedback adjustment voltage, calculate the sum of the voltages between the carton clamp basic feedforward voltage and the carton clamp feedback adjustment voltage, and generate the compensation adjustment input voltage.

[0011] As a further aspect of the present invention, step S5 specifically comprises: S501: When the rate of change of the carton clamping force error exceeds the preset upper limit threshold of the carton clamp error rate or is less than the preset lower limit threshold of the carton clamp error rate, calculate the product between the compensation adjustment input voltage and the preset carton clamp attenuation safety factor to obtain the updated compensation adjustment input voltage. S502: Use a digital-to-analog converter to convert the updated compensation adjustment input voltage into an analog control signal for the carton clamp motor drive, and send the analog control signal for the carton clamp motor drive to the control forklift oil valve associated drive motor; S503: After the segmented contact state indicator indicates the completion of the stable clamping stage of the carton clamp, control the forklift to lift the goods and move them to the set placement position and release the carton clamp. The simulated control signal of the carton clamp motor drive sent to the control forklift oil valve associated drive motor and the control signal of the carton clamp release action are combined to generate an adaptive adjustment command for the carton clamp clamping force.

[0012] An adaptive clamping force adjustment system for carton clamps, comprising: The feature acquisition module acquires a set of dynamic mechanical feature parameters of the cardboard box clamp of the forklift during the clamping and moving process; The state division module, based on the set of dynamic mechanical characteristic parameters, divides the operation stages of the carton clamp during the clamping and moving process, and generates segmented contact state identifiers. The state determination module calculates the current carton clamping force error when the clamp moves to the specified segment contact state in the segment contact state identifier, and determines the sliding variable state of the sliding surface by combining the preset sliding form ratio adjustment coefficient. The compensation setting module sets the compensation adjustment input voltage of the carton clamp based on the segmented contact state identifier and the state symbol of the sliding variable state of the sliding surface; The instruction generation module generates a carton clamp action control signal based on the compensation and adjustment input voltage, and outputs an adaptive adjustment instruction for the carton clamp clamping force.

[0013] Compared with the prior art, the advantages and positive effects of the present invention are as follows: In this invention, dynamic mechanical characteristic parameters of the carton clamp during its movement are first acquired. Then, the clamping process is divided into stages based on these parameters. At different stages, the clamping force error changes to determine the compensation adjustment input. This allows the clamping force adjustment to change synchronously with the progress of the clamping process, rather than being limited to the detection result at a single moment. Furthermore, this invention introduces adjustments for the current error state during the clamping establishment stage, and further corrects the input based on the current state during the stabilization clamping stage. Therefore, it not only ensures a higher consistency between the clamping force adjustment process and the actual operation of the carton clamp, but also makes the output motion control signal more closely match the current clamping state. This improves the coordination of the clamping process, enhances the targeting of adjustments, and makes the final adaptive adjustment command more in line with actual handling needs. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the steps of the present invention; Figure 2 This is a detailed schematic diagram of S1 of the present invention; Figure 3 This is a detailed schematic diagram of S2 of the present invention; Figure 4 This is a detailed schematic diagram of S3 of the present invention; Figure 5 This is a detailed schematic diagram of S4 of the present invention; Figure 6 This is a detailed schematic diagram of S5 of the present invention; Figure 7 This is a system module diagram of the present invention. Detailed Implementation

[0016] The technical solution of the present invention will now be described with reference to the accompanying drawings.

[0017] Please see Figure 1 This invention provides a method for adaptive adjustment of clamping force for carton clamps, comprising the following steps: S1: Obtain the set of dynamic mechanical characteristic parameters of the forklift carton clamp during the clamping and moving process; S2: Based on the set of dynamic mechanical characteristic parameters, the operation stages of the carton clamp during the clamping and moving process are divided, and segmented contact state identifiers are generated; S3: When the clamp moves to the segmented contact state in the specified segmented contact state indicator, calculate the current carton clamping force error, and determine the sliding variable state of the sliding surface by combining the preset sliding form ratio adjustment coefficient. S4: Set the compensation adjustment input voltage of the carton clamp according to the status symbols of the segmented contact status and the sliding variable status of the sliding surface; S5: Generates the action control signal of the carton clamp based on the compensation adjustment input voltage, and outputs the carton clamp clamping force adaptive adjustment command.

[0018] The set of dynamic mechanical characteristic parameters includes the carton clamping displacement characteristics, carton clamping speed characteristics, and carton clamping contact force characteristics. The segmented contact state indicators include the carton clamping approach contact stage indicator, the carton clamping contact establishment stage indicator, and the carton clamping stable clamping stage indicator. The sliding surface sliding variable state is specifically the state value calculated by the current carton clamping force error and the sliding surface proportional adjustment coefficient. The compensation adjustment input voltage is specifically the voltage value calculated by the state symbols of the segmented contact state indicators and the sliding surface sliding variable state. The carton clamping force adaptive adjustment command includes the carton clamping action control signal.

[0019] Please see Figure 2 Step S1 is as follows: S101: Set the initial proportional overflow valve pressure of the forklift oil valve. During the continuous closing and clamping movement of the carton clamp, acquire the current sampling time record of the carton clamp and the previous time record of the carton clamp. Collect the first analog voltage signal of the carton clamp displacement output by the displacement sensor and the second analog voltage signal of the carton clamp force output by the force sensor on the carton clamp clamping mechanism. Use an analog-to-digital converter to convert the first analog voltage signal of the carton clamp displacement into the current carton clamp clamping displacement, and convert the second analog voltage signal of the carton clamp force into the current carton clamp contact force.

[0020] The initial pressure value is written into the current task record at the reference position of the clamping arm opening. This pressure value is determined item by item based on the maximum opening and closing stroke of the clamping arm, the effective working area of ​​the hydraulic cylinder, the transmission ratio, the contact area of ​​the clamping plate, the type of carton material, the number of layers of the carton sidewalls, and the external dimensions of the carton. First, the minimum non-collapse pressure value that the carton sidewalls can withstand is taken as the upper boundary, and then the minimum action pressure value that the hydraulic cylinder starts to produce continuous displacement is taken as the lower boundary. Then, a pressure value that can push the clamping arm to close smoothly is selected between the two. The forklift oil valve is a component that controls the output pressure of hydraulic oil; the proportional relief valve pressure is the target pressure value formed by the valve core opening; the carton clamp is the two-sided clamping arm mechanism used to clamp the carton goods; the clamping mechanism is the moving part formed by the clamping arms, guide rails, hydraulic cylinders, and clamping plates. Subsequently, the sampling time record is continuously output by the real-time clock chip on the control board and arranged in the sampling order to form time data; the displacement sensor continuously outputs raw voltage data that changes with the position of the clamping arm, and the force sensor continuously outputs raw voltage data that reflects the magnitude of the force on the clamping plate. Before the two data streams enter the conversion unit, they are first organized into raw data queues corresponding to the sampling sequence number, removing null values ​​caused by disconnections, continuously repeating invariant values, and distorted values ​​exceeding the upper limit of the range. Next, instantaneous jump points are removed from the displacement voltage data, and spike points caused by contact jitter are removed from the force voltage data. Then, the cleaned voltage data is matched item by item with the voltage scale in the sensor's factory calibration table to calculate the displacement and force values ​​at the current moment. The displacement value is the distance the clamping arm moves from the open reference position to the center; the force value is the pressure applied to the clamping plate after it contacts the side wall of the carton. Finally, the current carton clamping displacement and the current carton clamping contact force are generated.

[0021] S102: Calculate the time deviation between the current cardboard clamp sampling time record and the previous cardboard clamp advance time record to obtain the cardboard clamp sampling time deviation. Calculate the deviation between the current cardboard clamp holding displacement and the previous cardboard clamp advance displacement to obtain the cardboard clamp displacement change difference. Calculate the ratio of the cardboard clamp displacement change difference to the cardboard clamp sampling time deviation to obtain the current cardboard clamp holding displacement change rate. Calculate the deviation between the current cardboard clamp holding displacement change rate and the previous cardboard clamp advance displacement change rate to obtain the cardboard clamp velocity change difference. Calculate the ratio of the cardboard clamp velocity change difference to the cardboard clamp sampling time deviation to obtain the cardboard clamp holding displacement acceleration value.

[0022] The time records of two adjacent sampling points are processed for time deviation according to the sampling order to obtain a sampling interval for a unified time scale. Then, the current displacement record is compared with the previous valid displacement record for each item, and the displacement change is obtained. This displacement change is then mapped to the sampling interval to obtain the degree of displacement change per unit time. Here, the displacement change rate is the speed at which the clamping arm moves towards the cardboard box. Next, the previous valid speed record is read, and the current speed record is compared with the previous speed record for each item, and the speed change is obtained. This speed change is then mapped to the sampling interval to obtain the acceleration value. Here, the acceleration value is the degree of change in the clamping arm's movement speed between adjacent moments. In time-related processing, if the current time record is the same as the previous time record, that point is not further processed; if the current time record is later than the previous time record, that point is retained; if the current time record is earlier than the previous time record, that point is discarded. In the displacement-related processing, if the current displacement is greater than the previous displacement, it indicates that the clamping arm continues to move closer to the center; if the current displacement is equal to the previous displacement, it indicates that the clamping arm is in a stationary state; if the current displacement is less than the previous displacement, it indicates that the clamping arm has retracted, and this state is retained. Finally, the current moment's cardboard clamping displacement change rate and cardboard clamping displacement acceleration value are generated.

[0023] S103: Obtain the contact force of the carton clamp at the current moment corresponding to the previous moment's front force of the carton clamp, calculate the deviation between the contact force of the carton clamp at the current moment and the previous moment's front force of the carton clamp, obtain the difference in the change of the carton clamp contact force, and combine it with the carton clamp contact force, the carton clamping displacement change rate and the carton clamping displacement acceleration value to obtain a set of dynamic mechanical characteristic parameters.

[0024] The previous valid force record adjacent to the current sampling number is retrieved as the preceding force value. The force deviation between the current force record and the preceding force record is processed item by item to obtain the force change between adjacent sampling points. Subsequently, the force change, current force value, current velocity value, and current acceleration value are integrated into the same record according to the same sampling time, forming a synchronous record set. Each data item in this set comes from the previously continuously acquired real-time data; no uncollected data is inserted. If any of the four data items is missing at a certain sampling time, the record for that time is not included in subsequent use. This integration process involves writing a set of correspondences for the four data items at the same sampling point in chronological order, ensuring that the motion and force states retrieved later are from the same moment. Finally, a set of dynamic mechanical characteristic parameters is generated.

[0025] Please see Figure 3 Step S2 is as follows: S201: Based on the set of dynamic mechanical characteristic parameters, collect the average value of the historical carton clamping acceleration when items touch each other during multiple historical carton clamp handling cycles, and configure the average value of the historical carton clamping acceleration as the acceleration threshold for determining carton clamp contact and the acceleration threshold for determining carton clamp clamping at the stage boundary, respectively, and establish a set of carton clamp stage division determination thresholds.

[0026] Prepare the historical average acceleration values ​​corresponding to the item contact phase in multiple historical handling cycles. A historical handling cycle is a complete operation record of a carton clamp from opening, closing towards the middle, contacting the carton, clamping the carton, moving the carton, releasing the carton, and returning to the open state. Historical data is read one by one from the task storage area in the forklift control panel. The task storage area stores the time record, displacement record, force record, and state transition record for each handling process. After reading, it is first sorted by task number and sampling order, and then deleted tasks with power outages, manual emergency stops, no-load closing tasks, and sensor disconnection tasks. The historical moment of item contact needs to be confirmed one by one from the historical records. The confirmation process is to first find the sampling segment where the force record first continuously changes from zero to non-zero, then check whether the adjacent displacement velocities before and after the sampling segment are still in the closing state, and at the same time check whether the force value afterward continuously does not return to zero. The moment that meets these three conditions is marked as the historical contact moment. Subsequently, acceleration records of consecutive sampling points before and after each historical touch moment are extracted. Missing points and points with incorrect order are deleted, and the remaining acceleration values ​​are averaged one by one to obtain the historical average acceleration for the corresponding period. After obtaining the average values ​​for multiple periods, these average values ​​are sorted in ascending order. The contact determination acceleration threshold used for stage division is determined by finding the boundary value of the low-position segment that appears most frequently in sync with the touch mark in the sorted sequence; the acceleration threshold used for clamping determination is determined by finding the boundary value of the high-position segment that appears most frequently in sync with the clamping completion mark in the sorted sequence. The low-position segment corresponds to contact determination because the clamping arm is obstructed when it first contacts the carton, and the speed change is weakened, forming a set of average values ​​that are arranged earlier in the historical record; the high-position segment corresponds to clamping determination because the action gradually converges before clamping is completed, forming a set of stable average values ​​that are arranged later in the historical record. Finally, a set of carton clamping stage division determination thresholds is generated.

[0027] S202: Based on the carton clamp stage division judgment threshold set, compare the current carton clamp contact force, the current carton clamp clamping displacement change rate, the carton clamp clamping displacement acceleration value, and the carton clamp contact force change difference value with preset carton clamp contact force judgment threshold, preset carton clamp displacement change rate judgment threshold, carton clamp contact judgment acceleration threshold, carton clamp clamping judgment acceleration threshold, and preset carton clamp force change judgment threshold, respectively, to determine the current operating stage state of the carton clamp; the current operating stage state of the carton clamp includes: if the current carton clamp contact force does not exceed the carton clamp contact force judgment threshold. When the current carton clamp displacement change rate exceeds the carton clamp displacement change rate judgment threshold, the carton clamp operation state is divided into the carton clamp approach contact stage. When the carton clamp clamp displacement acceleration value is less than the carton clamp contact judgment acceleration threshold and the carton clamp contact force change difference value exceeds the carton clamp force change judgment threshold, it is confirmed that the carton clamp is in contact with the item and the carton clamp operation state is divided into the carton clamp contact establishment stage. When the carton clamp clamp displacement acceleration value exceeds the carton clamp clamping judgment acceleration threshold, it is confirmed that the carton clamp has completed the clamping of the goods and the carton clamp operation state is divided into the carton clamp stable clamping stage.

[0028] The contact force threshold is determined by extracting all force values ​​from historical handling records at the first instance of sustained force application, sorting them from smallest to largest, and selecting the boundary value that distinguishes between the non-contact and contact states. This value is used to represent the contact state because when the clamping plate is not in contact with the cardboard box, the force record remains close to zero for a long time, only continuously moving away from the zero value zone after actual contact. The displacement change rate threshold is determined by extracting velocity values ​​from historical records of unloaded closing and historical closing before contact, finding the boundary value that distinguishes between normal approaching action and abnormal stagnation. This value is used to represent the approaching contact stage because continuous closing should be maintained before contact; a velocity below this boundary value indicates that a normal approaching state has not been maintained. The force change threshold is determined by extracting force change records near the historical contact moment, finding the boundary value at the first contact where the force changes from a slow change to a rapid increase. This value is used to represent the contact state because when the side wall of the cardboard box is first touched, the force change changes from near zero to a significant increase. Each value is then compared sequentially. If the current force value does not exceed the contact force threshold and the current velocity value exceeds the displacement change rate threshold, the current state corresponds to the carton clamp approaching contact stage. If the current force value does not exceed the contact force threshold and the current velocity value does not exceed the displacement change rate threshold, the previous state record is retained. If the current acceleration value is less than the contact acceleration threshold and the current force change exceeds the force change threshold, the carton clamp is in the contact establishment stage. If the current acceleration value exceeds the clamping acceleration threshold, the carton clamp is in the stable clamping stage. If none of the above conditions are met, the current stage maintains the state of the previous sampling point. Finally, the current operating stage state of the carton clamp is generated.

[0029] S203: Generate segment contact status identifiers based on the current operating stage status of the carton clamp.

[0030] The segment contact state identifier uses fixed state values ​​to record the sequential information of different stages during the clamping process. During generation, a state value mapping table is first established, and then the current stage state and the current sampling time are written into the state record sequence. Here, only the stage identifier is written; previously formed displacement and force values ​​are not repeated, only the order of state changes is retained. To avoid short-term fluctuations at a single sampling point causing state switching, the continuity of adjacent state values ​​is checked. If the current state value appears only once and the preceding and following state values ​​are the same, the single-point state is rewritten to the same preceding and following state values; if the current state value is continuously maintained, it is retained as a continuous state. The basis for this rewriting is that the clamping process is continuous, and isolated changes at a single sampling point usually originate from instantaneous jitter, rather than a true stage transition. Finally, segment contact state identifiers are generated.

[0031] Please see Figure 4 Step S3 is as follows: S301: When the segmented contact status indicator indicates that the current state has entered the carton clamp contact establishment stage, start the set pause timer, obtain the set carton clamp target clamping force, calculate the carton clamp force deviation between the set carton clamp target clamping force and the carton clamp contact force at the current moment, and obtain the carton clamp clamping force error.

[0032] When the status indicator shows the state has entered the contact establishment phase, a pause timer is initiated. This timer record accumulates from the moment the clamping plate and the carton begin to establish contact, and is used to define a short control interval after contact establishment. The pause time is extracted one by one from the historical contact times until the force enters a continuously increasing state. Specifically, the time points from the approach contact phase to the contact establishment phase in historical tasks are first read, then the duration corresponding to the continuous increase of force from the initial contact value to the approach target clamping force after these time points is read. These durations are categorized and sorted according to carton material and carton size, and then a duration that can cover the contact establishment process of most similar cartons is selected. This duration is used because contact establishment is not completed instantaneously, but is a process in which the side walls of the carton are gradually compressed and form continuous force. Subsequently, the target clamping force is acquired. The target value is determined based on the carton material, number of layers, width, and cargo weight in the cargo data sheet. Specifically, it involves first reading the allowable lateral pressure range of the carton material, then reading the minimum anti-slip clamping force corresponding to the cargo weight. Next, the allowable lateral pressure range of the carton sidewalls is used as the upper boundary, and the clamping force required to prevent slippage during handling is used as the lower boundary. An appropriate force value is selected between these two and written into the task record. Then, the target clamping force is adjusted for force deviation from the current force value to obtain the current clamping error. Finally, the carton clamping force error is generated.

[0033] S302: Calculate the deviation between the current carton clamping force error and the previous carton clamping error to obtain the carton clamping error difference. Calculate the ratio of the carton clamping error difference to the preset carton clamping time interval to obtain the carton clamping force error change rate.

[0034] The system reads the current error value and the previous valid error record, processes the deviation between them, and obtains the error change value. Then, it reads the preset time interval. This time interval is taken from the current control sampling period. The setting process involves first reading the displacement sampling period and force sampling period from the sampling configuration table, then selecting the time interval to be used after synchronizing both and writing it into the current task. A fixed time interval is used to ensure that adjacent error changes are established on a unified time scale. Next, the error change value is correlated with the preset time interval to obtain the error change rate. If the current error value is greater than the previous error value, the error change value is positive, indicating that the difference between the target clamping force and the current force is widening; if the current error value is equal to the previous error value, the error change value is zero, indicating that the difference remains unchanged; if the current error value is less than the previous error value, the error change value is negative, indicating that the difference is narrowing. Finally, the error change rate of the carton clamp clamping force is generated.

[0035] S303: Set the sliding mode proportional adjustment coefficient, calculate the product of the carton clamping force error and the set sliding mode proportional adjustment coefficient to obtain the carton clamp proportional adjustment error, calculate the carton clamp control algebraic sum between the carton clamp proportional adjustment error and the carton clamping force error change rate, and establish the sliding variable state of the sliding mode surface.

[0036] Set a proportional adjustment coefficient. This coefficient is used to convert the current clamping error into a control input. The setting process involves first categorizing tasks into light-load, medium-load, and heavy-load cartons according to the cargo data sheet. Then, extracting the error convergence process between the target clamping force and the actual contact force from the historical handling records of the corresponding categories, comparing the error changes and the final clamping stability state line by line, and finding a proportional range that can gradually reduce the error without causing significant swayback. Finally, the median value corresponding to the current cargo category within this proportional range is written into the current task. This setting is necessary because the same error has different effects on the clamping arm action under different loads and different carton materials; the corresponding proportion must be determined according to the convergence process of similar cargo. Subsequently, the current error is correlated with the proportional adjustment coefficient to obtain the proportional adjustment error. The proportional adjustment error is then algebraically summed with the error change rate to form a sliding variable state. This state reflects both the current error magnitude and the direction of error change. If the algebraic sum is positive, it indicates that the current force is still deviating from the target direction and is increasing; if the algebraic sum is zero, it indicates that the current force state is in a state of equilibrium transition; if the algebraic sum is negative, it indicates that the current force deviation is converging. Finally, the sliding variable state of the sliding surface is generated.

[0037] Please see Figure 5 Step S4 is as follows: S401: Based on the segmented contact state identifier, the initial reference value of the carton clamp, the first safety gain value of the carton clamp against impact, and the second safety gain value of the carton clamp against disturbance are matched for the carton clamp approach contact stage, the carton clamp contact establishment stage, and the carton clamp stable clamping stage, respectively, as sliding mode control gain parameters.

[0038] The control gain parameters are matched based on the segmented contact state indicators. The control gain parameters are the control amplitude values ​​corresponding to different stages. The initial reference value is the basic control amplitude used in the approach contact stage; the first safety gain value for shock resistance is the control amplitude used in the contact establishment stage; and the second safety gain value for disturbance resistance is the control amplitude used in the stable clamping stage. The initial reference value is set by first extracting the control input values ​​from historical approach contact stage records when the clamping arms continuously close but have not yet touched the carton, deleting records of clamping arm stagnation and retraction, sorting the remaining input values, and selecting the intermediate segment value that can maintain the continuous approach of the clamping arms, and writing it into the stage parameter table. The first safety gain value for shock resistance is set by first reading the force increase records from historical contact establishment stages, extracting the control input change corresponding to the initial continuous increase of force, then filtering out the input segment that allows the force to continuously increase without sudden force jumps, and writing this segment into the stage parameters. The setting of the second safety gain value for disturbance rejection involves first reading the force fluctuation records during the movement, turning, and lifting of the forklift in the historical stable clamping phase, then extracting the control input segment that ensures the contact force remains convergent around the target clamping force, and writing this segment as the phase parameter. Subsequently, the system matches each status indicator: if the current state is the near-contact phase, the initial baseline value is used; if the current state is the contact establishment phase, the first safety gain value for shock resistance is used; if the current state is the stable clamping phase, the second safety gain value for disturbance rejection is used; if the current state has not officially switched, the control gain parameter value from the previous sampling point is continued. Finally, the sliding mode control gain parameter value is generated.

[0039] S402: Before the segmented contact status indicator indicates that the carton clamp has entered the stable clamping stage, calculate the product between the initial proportional relief valve pressure and the preset percentage increment to obtain the proportional relief valve pressure supplement amount, obtain the preset oil valve pressure-voltage conversion coefficient, and calculate the product between the proportional relief valve pressure supplement amount and the preset oil valve pressure-voltage conversion coefficient to obtain the carton clamp basic feedforward voltage amount.

[0040] Before entering the stable clamping stage, the initial pressure record and preset percentage increment are read. This percentage value is a supplementary ratio added to the initial pressure. The setting process involves first reading the oil valve pressure change records from the contact establishment stage to the stable clamping stage in historical tasks, then classifying these records according to carton quality range and carton material range, and calculating the pressure increase ratio of each type of carton relative to the initial pressure before clamping is completed. Then, common percentage ranges that allow the force to transition from the establishment state to the stable state are selected and written into the cargo parameter table. A percentage format is used because different initial pressures correspond to different absolute increments, and percentage increments maintain a consistent supplementary relationship for the same type of carton under different initial pressures. Subsequently, the initial pressure is correlated with the preset percentage increment to obtain the pressure supplement. Next, the conversion coefficient between pressure and voltage is read. The setting process for this coefficient involves first inputting different voltage values ​​step by step while the forklift is stationary, simultaneously collecting the actual oil pressure values ​​recorded by the pressure sensor, then compiling the actual oil pressure values ​​corresponding to each voltage level into a calibration table, and finally writing the conversion coefficients corresponding to different pressure zones according to the oil pressure change relationship of adjacent voltage ranges. The reason for partitioning is that the voltage and oil pressure changes of the proportional relief valve are not entirely consistent in different pressure zones. Then, the pressure replenishment amount is mapped to the conversion coefficient of the current pressure zone to obtain the basic feedforward voltage. Finally, the basic feedforward voltage of the carton clamp is generated.

[0041] S403: Convert the sliding variable state of the sliding surface into corresponding positive and negative sign values, calculate the product of the positive and negative sign values, the sliding control gain parameter, and the equivalent coefficient of the physical transfer relationship of the carton clamping mechanism. The equivalent coefficient of the physical transfer relationship of the carton clamping mechanism is set according to the mechanical transmission ratio and mechanical conversion efficiency of the carton clamp to obtain the feedback adjustment voltage of the carton clamp. Calculate the sum of the voltages between the basic feedforward voltage of the carton clamp and the feedback adjustment voltage of the carton clamp to generate the compensation adjustment input voltage.

[0042] The sliding variable state is converted into a directional state. If the sliding variable state represents a positive offset, the directional state is positive; if the sliding variable state represents a balanced state, the directional state is zero; if the sliding variable state represents a negative offset, the directional state is negative. Then, the control gain parameter and the equivalent coefficient of the clamping mechanism's entity transfer relationship are read. The process of setting this equivalent coefficient involves first reading the hydraulic cylinder displacement, transmission rod length, clamping arm rotation radius, and clamping plate force position from the carton clamp's mechanical structure diagram; then, matching the hydraulic cylinder output displacement with the clamping plate movement displacement item by item to form the mechanical transmission ratio; next, reading the hydraulic cylinder output force, hinge point friction loss, and actual clamping plate force record, matching the output force with the clamping plate force item by item to form the mechanical conversion efficiency; finally, writing the mechanical transmission ratio and mechanical conversion efficiency into the same correspondence table, and finding the equivalent coefficient under the current clamping position. This coefficient is needed because input changes do not directly equal clamping plate force changes; there is also a mechanical transmission and force conversion relationship involved. Subsequently, the direction state, control gain parameters, and equivalent coefficients are mapped to obtain the feedback adjustment voltage. The base feedforward voltage and the feedback adjustment voltage are then summed to obtain the current compensation input value. If the direction state is positive, the feedback adjustment voltage is superimposed along the current feedforward input direction; if the direction state is zero, the feedback adjustment voltage does not participate in the superposition; if the direction state is negative, the feedback adjustment voltage is superimposed along the opposite direction of the feedforward input. Finally, the compensation adjustment input voltage is generated.

[0043] Please see Figure 6 Step S5 is as follows: S501: When the rate of change of the carton clamping force error exceeds the preset upper limit threshold of the carton clamp error rate or is less than the preset lower limit threshold of the carton clamp error rate, calculate the product between the compensation adjustment input voltage and the preset carton clamp attenuation safety factor to obtain the updated compensation adjustment input voltage.

[0044] The error change rate is read and compared with the upper and lower thresholds for error change rate. The upper threshold is set by first reading all error change rate records by task category, then filtering out records that ultimately failed to return to the vicinity of the target clamping force within a short time. The corresponding error change rates for these records are then compiled, and the boundary value that repeatedly appears when the error begins to significantly increase is found and written into the upper threshold table. This value corresponds to the upper limit because exceeding this value indicates that the current clamping error is deviating from the normal convergence zone. The lower threshold is set by first filtering out records where the force rapidly approaches the target clamping force and then swings back, then compiling the corresponding error change rates for these records, finding the boundary value that repeatedly appears when the error decreases too quickly, and writing this boundary value into the lower threshold table. This value corresponds to the lower limit because being below this value indicates that the current clamping error is decreasing too quickly, which can easily cause reverse fluctuations later. The current compensation input value and attenuation safety factor are then read. This coefficient is a convergent compression ratio based on the current input. The setting process involves first reading all records from historical tasks where the input value needs to be reduced, then mapping the input value before reduction to the stable value after reduction in each record, compiling common compression ratios, and then selecting the ratio range that allows the error rate of change to return to between the upper and lower thresholds. This ratio range is written as the attenuation safety factor. If the error rate of change exceeds the upper threshold, the current compensation input value is mapped to the attenuation safety factor; if the error rate of change is less than the lower threshold, the same mapping is performed; if the error rate of change is between the upper and lower thresholds, the current compensation input value remains unchanged. Finally, an updated compensation adjustment input voltage is generated.

[0045] S502: The digital-to-analog converter is used to convert the updated compensation adjustment input voltage into an analog control signal for the carton clamp motor drive, and the analog control signal for the carton clamp motor drive is sent to the drive motor associated with the control forklift oil valve.

[0046] The updated input value is sent to the conversion unit to obtain a continuous control voltage, which is then sent to the drive motor connected to the oil valve via the drive circuit. Here, the drive analog control signal is a continuous voltage directly sent to the drive motor control terminal; the drive motor connected to the oil valve is the actuator that drives the proportional relief valve. Before sending, it checks whether the updated input value falls within the drive motor's allowable input range; if it is below the lower allowable boundary, it is sent according to the lower boundary; if it is above the upper allowable boundary, it is sent according to the upper boundary; if it is within the allowable range, it is sent according to the current value. This allowable input range is obtained by combining the drive motor's nameplate rated input range, the oil valve response voltage range, and historical stable operation records. The reason for checking the range first is that the drive motor's oil valve action only matches the previously established pressure and voltage correspondence if it is within the allowable input range. Finally, a carton clamp motor drive analog control signal is generated and sent to the drive motor associated with the control forklift's oil valve.

[0047] S503: After the segmented contact status indicator indicates the completion of the stable clamping stage of the carton clamp, control the pallet truck to lift the goods and move them to the set placement position and release the carton clamp. The simulated control signal of the carton clamp motor drive sent to the control pallet truck oil valve associated drive motor and the control signal of the carton clamp release action are combined to generate an adaptive adjustment command for the carton clamp clamping force.

[0048] Under the control of industrial control software, after maintaining a stable clamping state for the duration set in the task parameter table, the forklift performs lifting and transfer. The process of setting this duration involves reading the time record from entering the stable clamping state to starting to lift the goods from historical tasks, categorizing and organizing the data by carton quality and material, and selecting common durations required to achieve stable clamping for similar cartons, which are then written into the task table. This duration is necessary because a stable clamping state needs to be maintained continuously to indicate that a force relationship has been established between the clamp and the carton that allows for continued handling. Upon reaching the target location, the clamping arm retracts along the opening direction until the contact force returns to an unloaded state. Subsequently, the industrial control software writes the previously sent drive control signals and release action control signals into the same task record in chronological order, and organizes them together with the current task number and stage state transition record to form a summary of adjustment instructions for this clamping task. Finally, the industrial control software generates an adaptive adjustment instruction for the carton clamping force.

[0049] Please see Figure 7 An adaptive clamping force adjustment system for carton clamps, comprising: The feature acquisition module acquires a set of dynamic mechanical feature parameters of the cardboard box clamp of the forklift during the clamping and moving process; The state segmentation module, based on a set of dynamic mechanical characteristic parameters, divides the operating stages of the carton clamp during the clamping and moving process, and generates segmented contact state identifiers. The state determination module calculates the current carton clamping force error when the clamp moves to the segmented contact state in the specified segmented contact state indicator, and determines the sliding variable state of the sliding surface by combining the preset sliding form ratio adjustment coefficient. The compensation setting module sets the compensation adjustment input voltage of the carton clamp based on the segment contact state indicator and the state symbol of the sliding variable state of the sliding surface. The instruction generation module generates motion control signals for the carton clamp based on the compensation and adjustment input voltage, and outputs an adaptive adjustment instruction for the carton clamp clamping force.

[0050] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for adaptive adjustment of clamping force for carton clamps, characterized in that, Includes the following steps: S1: Obtain the set of dynamic mechanical characteristic parameters of the forklift carton clamp during the clamping and moving process; S2: Based on the set of dynamic mechanical characteristic parameters, divide the operation stages of the carton clamp during the clamping and moving process, and generate segmented contact state identifiers; S3: When the clamp moves to the segmented contact state specified in the segmented contact state identifier, calculate the current carton clamping force error, and determine the sliding variable state of the sliding surface by combining the preset sliding form ratio adjustment coefficient. S4: Set the compensation adjustment input voltage of the carton clamp according to the segmented contact state identifier and the state symbol of the sliding variable state of the sliding surface; S5: Generate a carton clamp action control signal based on the compensated and adjusted input voltage, and output a carton clamp clamping force adaptive adjustment command.

2. The adaptive adjustment method for clamping force of a carton clamp according to claim 1, characterized in that, The set of dynamic mechanical characteristic parameters includes the carton clamping displacement characteristics, the carton clamping moving speed characteristics, and the carton clamping contact force characteristics. The segmented contact state identifiers include the carton clamping approach contact stage identifier, the carton clamping contact establishment stage identifier, and the carton clamping stable clamping stage identifier. The sliding surface sliding variable state is specifically a state value calculated by the current carton clamping force error and the sliding surface proportional adjustment coefficient. The compensation adjustment input voltage is specifically a voltage value calculated by the state symbols of the segmented contact state identifiers and the sliding surface sliding variable state. The carton clamping force adaptive adjustment command includes the carton clamping action control signal.

3. The adaptive adjustment method for clamping force of a carton clamp according to claim 1, characterized in that, Step S1 is as follows: S101: Set the initial proportional overflow valve pressure of the forklift oil valve. During the continuous closing and clamping movement of the carton clamp towards the middle, acquire the current sampling time record of the carton clamp and the previous time record of the carton clamp. Collect the first analog voltage signal of the carton clamp displacement output by the displacement sensor and the second analog voltage signal of the carton clamp force output by the force sensor on the carton clamp clamping mechanism. Use an analog-to-digital converter to convert the first analog voltage signal of the carton clamp displacement into the current carton clamp clamping displacement and the second analog voltage signal of the carton clamp force into the current carton clamp contact force. S102: Calculate the time deviation between the current cardboard clamp sampling time record and the previous cardboard clamp advance time record to obtain the cardboard clamp sampling time deviation. Calculate the deviation between the current cardboard clamp holding displacement and the previous cardboard clamp advance displacement to obtain the cardboard clamp displacement change difference. Calculate the ratio of the cardboard clamp displacement change difference to the cardboard clamp sampling time deviation to obtain the current cardboard clamp holding displacement change rate. Calculate the deviation between the current cardboard clamp holding displacement change rate and the previous cardboard clamp advance displacement change rate to obtain the cardboard clamp velocity change difference. Calculate the ratio of the cardboard clamp velocity change difference to the cardboard clamp sampling time deviation to obtain the cardboard clamp holding displacement acceleration value. S103: Obtain the previous carton clamp's front force corresponding to the current carton clamp contact force, calculate the deviation between the current carton clamp contact force and the previous carton clamp's front force, obtain the carton clamp contact force change difference value, and combine it with the carton clamp contact force, the carton clamp clamping displacement change rate, and the carton clamp clamping displacement acceleration value to obtain a set of dynamic mechanical characteristic parameters.

4. The adaptive adjustment method for clamping force of a carton clamp according to claim 1, characterized in that, Step S2 is as follows: S201: Based on the set of dynamic mechanical characteristic parameters, collect the average value of the historical carton clamping acceleration when items touch each other during multiple historical carton clamp handling cycles, and configure the average value of the historical carton clamping acceleration as the acceleration threshold for determining carton clamp contact at the stage boundary and the acceleration threshold for determining carton clamp clamping, respectively, and establish a set of carton clamp stage division determination thresholds; S202: Based on the set of thresholds for determining the carton clamp stage, the current carton clamp contact force, the current carton clamp displacement change rate, the carton clamp displacement acceleration value, and the carton clamp contact force change difference are compared with preset carton clamp contact force determination thresholds, preset carton clamp displacement change rate determination thresholds, carton clamp contact determination acceleration thresholds, carton clamp clamping determination acceleration thresholds, and preset carton clamp force change thresholds to determine the current operating stage state of the carton clamp; S203: Generate segment contact status identifiers based on the current operating stage status of the carton clamp.

5. The adaptive adjustment method for clamping force of a carton clamp according to claim 4, characterized in that, The current operating state of the carton clamp includes: if the contact force of the carton clamp does not exceed the carton clamp contact force judgment threshold at the current moment and the carton clamp clamping displacement change rate exceeds the carton clamp displacement change rate judgment threshold at the current moment, the carton clamp operating state is divided into the carton clamp approach contact stage; when the carton clamp clamping displacement acceleration value is less than the carton clamp contact judgment acceleration threshold and the carton clamp contact force change difference value exceeds the carton clamp force change judgment threshold, it is confirmed that the carton clamp is touching the item and the carton clamp operating state is divided into the carton clamp contact establishment stage; when the carton clamp clamping displacement acceleration value exceeds the carton clamp clamping judgment acceleration threshold, it is confirmed that the carton clamp has completed the clamping of the goods and the carton clamp operating state is divided into the carton clamp stable clamping stage.

6. The adaptive adjustment method for clamping force of a carton clamp according to claim 5, characterized in that, Step S3 is as follows: S301: When the segmented contact status indicator indicates that the current state has entered the carton clamp contact establishment stage, start the set pause timer, obtain the set carton clamp target clamping force, calculate the carton clamp force deviation between the set carton clamp target clamping force and the carton clamp contact force at the current moment, and obtain the carton clamp clamping force error. S302: Calculate the deviation between the current carton clamping force error and the previous carton clamping error to obtain the carton clamping error difference value. Calculate the ratio of the carton clamping error difference value to the preset carton clamping time interval to obtain the carton clamping force error change rate. S303: Set the sliding mode ratio adjustment coefficient, calculate the product of the carton clamping force error and the set sliding mode ratio adjustment coefficient to obtain the carton clamp ratio adjustment error, calculate the carton clamp control algebraic sum between the carton clamp ratio adjustment error and the carton clamping force error change rate, and establish the sliding variable state of the sliding mode surface.

7. The adaptive adjustment method for clamping force of a carton clamp according to claim 5, characterized in that, Step S4 is as follows: S401: Based on the segmented contact state identifier, the initial reference value of the carton clamp, the first safety gain value of the carton clamp against impact, and the second safety gain value of the carton clamp against disturbance are respectively matched for the carton clamp approach contact stage, the carton clamp contact establishment stage, and the carton clamp stable clamping stage, as sliding mode control gain parameters. S402: Before the segmented contact state indicator indicates that the carton clamp has entered the stable clamping stage, calculate the product between the initial proportional overflow valve pressure and the preset percentage increment to obtain the proportional overflow valve pressure supplement amount, obtain the preset oil valve pressure-voltage conversion coefficient, and calculate the product between the proportional overflow valve pressure supplement amount and the preset oil valve pressure-voltage conversion coefficient to obtain the carton clamp basic feedforward voltage amount. S403: Convert the sliding variable state of the sliding surface into corresponding positive and negative sign values, calculate the product of the positive and negative sign values, the sliding control gain parameter, and the equivalent coefficient of the preset carton clamping mechanism entity transfer relationship to obtain the carton clamp feedback adjustment voltage, calculate the sum of the voltages between the carton clamp basic feedforward voltage and the carton clamp feedback adjustment voltage, and generate the compensation adjustment input voltage.

8. The adaptive adjustment method for clamping force of a carton clamp according to claim 7, characterized in that, The equivalent coefficient of the physical transfer relationship of the carton clamp holding mechanism is set according to the mechanical transmission ratio and mechanical conversion efficiency of the carton clamp.

9. The adaptive adjustment method for clamping force of a carton clamp according to claim 1, characterized in that, Step S5 is as follows: S501: When the rate of change of the carton clamping force error exceeds the preset upper limit threshold of the carton clamp error rate or is less than the preset lower limit threshold of the carton clamp error rate, calculate the product between the compensation adjustment input voltage and the preset carton clamp attenuation safety factor to obtain the updated compensation adjustment input voltage. S502: Use a digital-to-analog converter to convert the updated compensation adjustment input voltage into an analog control signal for the carton clamp motor drive, and send the analog control signal for the carton clamp motor drive to the control forklift oil valve associated drive motor; S503: After the segmented contact state indicator indicates the completion of the stable clamping stage of the carton clamp, control the forklift to lift the goods and move them to the set placement position and release the carton clamp. The simulated control signal of the carton clamp motor drive sent to the control forklift oil valve associated drive motor and the control signal of the carton clamp release action are combined to generate an adaptive adjustment command for the carton clamp clamping force.

10. A clamping force adaptive adjustment system for carton clamps, characterized in that, The system is used to implement the adaptive adjustment method for clamping force of a carton clamp as described in any one of claims 1-9, the system comprising: The feature acquisition module acquires a set of dynamic mechanical feature parameters of the cardboard box clamp of the forklift during the clamping and moving process; The state division module, based on the set of dynamic mechanical characteristic parameters, divides the operating stages of the carton clamp during the clamping and moving process, and generates segmented contact state identifiers. The state determination module calculates the current carton clamping force error when the clamp moves to the specified segment contact state in the segment contact state identifier, and determines the sliding variable state of the sliding surface by combining the preset sliding form ratio adjustment coefficient. The compensation setting module sets the compensation adjustment input voltage of the carton clamp based on the segmented contact state identifier and the state symbol of the sliding variable state of the sliding surface; The instruction generation module generates a carton clamp action control signal based on the compensation and adjustment input voltage, and outputs an adaptive adjustment instruction for the carton clamp clamping force.

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