Synchronous horizontal control method and system for telescopic arm and pallet fork of forklift loader

Abstract

The embodiment of the invention provides a synchronous horizontal control method and system for a telescopic arm and a pallet fork of a forklift loader, and relates to the technical field of forklift loader control. The method comprises the steps that hydraulic oil temperature information, vehicle body vibration strength information, cargo sensitivity information and real-time posture information of the pallet fork are obtained; according to the hydraulic oil temperature information, the vehicle body vibration intensity information and the cargo sensitivity information, dynamic calculation is conducted, and the pallet fork posture deviation tolerance is obtained; comparing the real-time posture information of the pallet fork with a target horizontal posture to obtain a posture deviation; when the absolute value of the attitude deviation exceeds the tolerance of the pallet fork attitude deviation, a smoothing instruction is generated; and the posture of the pallet fork is adjusted according to the smoothing instruction until the absolute value of the posture deviation returns to the range of the tolerance of the posture deviation of the pallet fork. According to the invention, the overall efficiency of loading, unloading or accurate placement operation can be improved.

Description

Technical Field

[0001] This application relates to the field of forklift control technology, and in particular to a method and system for synchronous horizontal control of the telescopic boom and forks of a forklift. Background Technology

[0002] In modern industrial logistics and large-scale construction sites, forklifts, as critical material handling equipment, often require continuous and high-frequency operation of their telescopic booms and forks. For example, in large precast component production bases, forklifts may need to continuously transfer heavy precast concrete slabs from the curing area to the stacking area, or methodically move bundles of structural steel across a vast construction area. These tasks are characterized by high intensity and long duration, typically spanning multiple shifts, during which the telescopic boom repeatedly extends, retracts, raises, and lowers to ensure precise placement of goods. This continuous and high-intensity operating mode places constant operational pressure on various subsystems of the forklift. Under prolonged, high-intensity continuous operation, the temperature of the forklift's hydraulic system gradually increases, leading to a decrease in hydraulic oil viscosity, which in turn affects the response characteristics of the hydraulic actuators. Meanwhile, when forklifts operate on uneven terrain, the vehicle chassis is continuously subjected to low-amplitude, high-frequency mechanical vibrations. These vibrations are transmitted to the angle and attitude sensors installed on the telescopic boom and fork connector, resulting in the sensor raw data output containing a large amount of superimposed "high-frequency noise". Summary of the Invention

[0003] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a method and system for synchronous horizontal control of the telescopic boom and forks of a forklift, aiming to improve the overall efficiency of loading, unloading, or precise placement operations.

[0004] In a first aspect, embodiments of this application provide a method for synchronously horizontally controlling the telescopic boom and forks of a forklift, including:

[0005] Acquire information on hydraulic oil temperature, vehicle vibration intensity, cargo sensitivity, and real-time fork attitude.

[0006] The tolerance for fork posture deviation is obtained by dynamically calculating based on the hydraulic oil temperature information, the vehicle body vibration intensity information, and the cargo sensitivity information.

[0007] The real-time attitude information of the forks is compared with the target horizontal attitude to obtain the attitude deviation;

[0008] When the absolute value of the attitude deviation exceeds the tolerance of the fork attitude deviation, a smoothing command is generated;

[0009] The fork posture is adjusted according to the smoothing command until the absolute value of the posture deviation returns to the range of the fork posture deviation tolerance.

[0010] According to some embodiments of this application, the real-time attitude information of the forks is obtained through the following steps:

[0011] Obtain the original posture information of the forks;

[0012] Frequency analysis is performed on the original attitude information to obtain the resonance amplitude, and the resonance oscillation characteristics are identified based on the resonance amplitude and a preset threshold.

[0013] Based on the identified resonant oscillation characteristics, an inverse signal opposite to the resonant oscillation in the resonant oscillation characteristics is generated;

[0014] The reverse signal is extracted from the original attitude information to obtain the real-time attitude information of the fork.

[0015] According to some embodiments of this application, generating a smoothing command when the absolute value of the attitude deviation exceeds the fork attitude deviation tolerance includes:

[0016] When the absolute value of the attitude deviation exceeds the tolerance of the fork attitude deviation, the real-time response characteristic information of the hydraulic actuator is obtained;

[0017] Based on the real-time response characteristics of the hydraulic actuator, the generation parameters of the smoothing command are dynamically adjusted to obtain the target generation parameters, wherein the generation parameters include the rise time, fall time, and rate of change of the command.

[0018] A smoothing instruction is generated based on the target generation parameters.

[0019] According to some embodiments of this application, generating a smoothing command when the absolute value of the attitude deviation exceeds the fork attitude deviation tolerance includes:

[0020] When the absolute value of the attitude deviation exceeds the tolerance of the fork attitude deviation, the real-time viscosity information of the hydraulic oil is obtained;

[0021] Based on the hydraulic oil temperature information and the real-time viscosity information, a viscosity-temperature characteristic curve of the hydraulic oil is established in real time.

[0022] Based on the viscosity-temperature characteristic curve, a smoothing instruction is generated.

[0023] According to some embodiments of this application, the step of dynamically adjusting the generation parameters of the smoothing command based on the real-time response characteristic information of the hydraulic actuator to obtain the target generation parameters includes:

[0024] Acquire information on the weight of the goods, the position of the center of gravity, and the rate of change of the fork's posture;

[0025] Based on the weight information of the cargo, the center of gravity position information, the attitude change rate information of the forks, and the real-time response characteristic information of the hydraulic actuator, the generation parameters of the smoothing command are dynamically adjusted to obtain the target generation parameters.

[0026] According to some embodiments of this application, the real-time viscosity information of the hydraulic oil is obtained through the following steps:

[0027] Obtain the dielectric constant information of the hydraulic oil;

[0028] Obtain target oil particle size distribution information for hydraulic oil;

[0029] Based on the dielectric constant information, assess the degree of oxidation product accumulation in the hydraulic oil;

[0030] The degree of shear dilution of the hydraulic oil is evaluated based on the target oil particle size distribution information.

[0031] The real-time viscosity information of the hydraulic oil is obtained based on the degree of accumulation of the oxidation products and the degree of shear dilution.

[0032] According to some embodiments of this application, evaluating the shear dilution degree of the hydraulic oil based on the target oil particle size distribution information includes:

[0033] The wear particle characteristic information of hydraulic oil is obtained based on the target oil particle size distribution information, wherein the wear particle characteristic information includes the shape characteristics and material characteristics of the wear particles;

[0034] Based on the target oil particle size distribution information, the shear dilution particle characteristic information of the hydraulic oil is obtained, wherein the shear dilution particle characteristic information includes the size range and morphological characteristics of the shear dilution particles;

[0035] Based on the wear particle characteristic information and the shear dilution particle characteristic information, identify and distinguish wear particles and shear dilution particles in the target oil particle size distribution information;

[0036] The degree of shear dilution of the hydraulic oil is assessed based on the wear particles and the shear dilution particles.

[0037] According to some embodiments of this application, evaluating the degree of oxidation product accumulation of the hydraulic oil based on the dielectric constant information includes:

[0038] Obtain initial dielectric constant information and dielectric constant variation characteristics of oxidation products for various types of additives in hydraulic oil;

[0039] Based on the dielectric constant information, the initial dielectric constant information of each type of additive, and the dielectric constant change characteristics of the oxidation products, the contribution values ​​of the oxidation products of different types of additives to the dielectric constant information are identified and distinguished.

[0040] The accumulation degree of each type of oxidation product is quantified based on the identified contribution value, and the accumulation degree is superimposed to obtain the accumulation degree of oxidation products of the hydraulic oil.

[0041] According to some embodiments of this application, obtaining the target oil particle size distribution information of the hydraulic oil includes:

[0042] Obtain the original oil particle size distribution information of the hydraulic oil;

[0043] Obtain the pollution source characteristic information of hydraulic oil, including the morphological characteristics of dust particles in the external environment and the material characteristics of worn metal debris;

[0044] Based on the original oil particle size distribution information and the pollution source characteristic information, identify particles from non-oil sources in the original oil particle size distribution information;

[0045] The target oil particle size distribution information is obtained by removing particles from the original oil particle size distribution information that are not from oil.

[0046] Secondly, embodiments of this application provide a synchronous horizontal control system for the telescopic boom and forks of a forklift, comprising:

[0047] The acquisition module is used to acquire hydraulic oil temperature information, vehicle body vibration intensity information, cargo sensitivity information, and real-time fork attitude information.

[0048] The calculation module is used to dynamically calculate the fork posture deviation tolerance based on the hydraulic oil temperature information, the vehicle body vibration intensity information, and the cargo sensitivity information.

[0049] The comparison module is used to compare the real-time attitude information of the forks with the target horizontal attitude to obtain the attitude deviation;

[0050] The instruction generation module is used to generate a smooth instruction when the absolute value of the attitude deviation exceeds the tolerance of the fork attitude deviation.

[0051] The adjustment module is used to adjust the posture of the forks according to the smoothing command until the absolute value of the posture deviation returns to the range of the fork posture deviation tolerance.

[0052] The technical solution according to the embodiments of this application has at least the following beneficial effects: The synchronous horizontal control method for the telescopic boom and forks of a forklift truck disclosed in this application dynamically calculates the tolerance for fork posture deviation by acquiring hydraulic oil temperature information, vehicle vibration intensity information, and cargo sensitivity information, and compares the real-time posture information of the forks with the target horizontal posture. When the posture deviation exceeds the tolerance, a smoothing command is generated for adjustment. This method effectively solves the problems in the prior art where, under long-term, high-intensity operating conditions, the hydraulic oil temperature rises, leading to a decrease in viscosity; vehicle vibration introduces sensor noise; and the fixed-parameter smoothing processing program cannot adapt to complex working conditions. Specifically, this application avoids the traditional control system misjudging minor fluctuations as real deviations by dynamically adjusting the posture deviation tolerance, thereby reducing frequent and small-amplitude adjustment commands, effectively suppressing excessive action of the electromagnetic proportional valve and local instantaneous pressure fluctuations of the hydraulic oil, and eliminating the "lag" or "overcorrection" of the fork leveling action. At the same time, by generating smoothing commands for posture adjustment, the smoothness of the fork leveling action and precise synchronization with the overall movement of the telescopic boom are ensured, overcoming the problem of "minor inconsistencies in pace" in the prior art. Therefore, this application significantly improves the leveling accuracy and stability of the forks, effectively avoids shaking, tilting or vibrating of goods during handling, reduces the cognitive load and fatigue of operators, greatly improves the overall efficiency of loading, unloading or precise placement operations, and significantly reduces the risk of accidents.

[0053] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0054] The accompanying drawings are used to provide a further understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.

[0055] Figure 1 This is a flowchart illustrating a method for synchronous horizontal control of a forklift telescopic boom and forks according to an embodiment of this application.

[0056] Figure 2 This is a schematic diagram of a synchronous horizontal control system for a forklift telescopic boom and forks provided in one embodiment of this application. Detailed Implementation

[0057] To make the objectives, technical methods, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0058] It should be noted that the meaning of "multiple" (or "more than") in the description of the embodiments of this application refers to two or more, and "greater than," "less than," "exceeding," etc. are understood to exclude the number itself, while "above," "below," "within," etc. are understood to include the number itself. If "first," "second," etc. are used in the description, they are only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated or the order of the technical features indicated.

[0059] In this application embodiment, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent the existence of A alone, the simultaneous existence of A and B, or the existence of B alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of singular or plural items. For example, at least one of a, b, and c can represent: the existence of a alone, the existence of b alone, the existence of c alone, the simultaneous existence of a and b, the simultaneous existence of a and c, the simultaneous existence of b and c, or the simultaneous existence of a, b, and c, where a, b, and c can be single or multiple.

[0060] In the description of this application, unless otherwise expressly defined, terms such as "setup," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this application in conjunction with the specific content of the technical solution.

[0061] Based on the above, this application proposes a method and system for synchronous horizontal control of the telescopic boom and forks of a forklift, aiming to improve the overall efficiency of loading, unloading or precise placement operations.

[0062] The forklift telescopic boom and fork synchronous horizontal control method provided in this application embodiment can be applied to a terminal, a server, or software running on either a terminal or a server. In some embodiments, the terminal can be a smartphone, tablet, laptop, desktop computer, etc.; the server can be configured as an independent physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server providing basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, content delivery networks (CDN), and big data and artificial intelligence platforms; the software can be an application that implements the forklift telescopic boom and fork synchronous horizontal control method, but is not limited to the above forms.

[0063] This application can be applied to numerous general-purpose or special-purpose computer system environments or configurations. Examples include: personal computers, server computers, handheld or portable devices, tablet devices, multiprocessor systems, microprocessor-based systems, set-top boxes, programmable consumer electronics devices, network PCs, minicomputers, mainframe computers, and distributed computing environments including any of the above systems or devices. This application can be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform specific tasks or implement specific abstract data types. This application can also be practiced in distributed computing environments where tasks are performed by remote processing devices connected via communication networks. In distributed computing environments, program modules can reside in local and remote computer storage media, including storage devices. It should be noted that in various specific embodiments of this invention, when processing is required based on data related to the characteristics of an object (e.g., user attributes or sets of attribute information), permission or consent from the corresponding object is obtained first, and the collection, use, and processing of this data comply with relevant laws and standards. Furthermore, when the embodiments of the present invention need to obtain the attribute information of an object, they will obtain the separate permission or separate consent of the corresponding object through pop-up windows or redirection to a confirmation page. After obtaining the separate permission or separate consent of the corresponding object, they will then obtain the relevant data of the object necessary for the embodiments of the present invention to operate normally.

[0064] See Figure 1 , Figure 1 This is a flowchart illustrating a method for synchronously controlling the horizontal position of a forklift telescopic boom and forks according to an embodiment of this application. The method includes, but is not limited to, steps S110 to S150, which will be described in detail below.

[0065] Step S110: Obtain hydraulic oil temperature information, vehicle body vibration intensity information, cargo sensitivity information, and real-time fork attitude information;

[0066] Step S120: Dynamically calculate the tolerance of fork posture deviation based on hydraulic oil temperature information, vehicle vibration intensity information and cargo sensitivity information;

[0067] Step S130: Compare the real-time attitude information of the forks with the target horizontal attitude to obtain the attitude deviation;

[0068] Step S140: When the absolute value of the attitude deviation exceeds the tolerance of the fork attitude deviation, a smoothing command is generated;

[0069] Step S150: Adjust the fork posture according to the smoothing command until the absolute value of the posture deviation returns to the range of the fork posture deviation tolerance.

[0070] It should be noted that "hydraulic oil temperature information" refers to the real-time temperature data of the hydraulic oil in the hydraulic system. This information is crucial for assessing changes in hydraulic oil viscosity and the operating status of the hydraulic system. "Vehicle vibration intensity information" refers to the amplitude and frequency of vibration experienced by the forklift vehicle during operation. This information reflects the complexity of the operating environment and its potential impact on sensor data. "Cargo sensitivity information" refers to the sensitivity of the transported cargo to changes in posture. For example, fragile or unstable goods are more sensitive to posture changes and require stricter control precision. "Real-time fork posture information" refers to the actual spatial position and angle data of the forks at any given time, usually obtained through sensors. "Target horizontal posture" refers to the ideal horizontal state that the forks should maintain during operation. "Posture deviation" refers to the difference between the real-time fork posture information and the target horizontal posture. "Fork posture deviation tolerance" refers to the maximum range of deviation of the fork posture from the target horizontal posture allowed under specific operating conditions; adjustments are required if this range is exceeded. "Smoothing command" refers to the control signal used to adjust the hydraulic actuator to smoothly return the fork posture to the target horizontal posture.

[0071] In one embodiment, it is necessary to acquire hydraulic oil temperature information, vehicle body vibration intensity information, cargo sensitivity information, and real-time fork attitude information. Hydraulic oil temperature information can be obtained through temperature sensors installed on the hydraulic oil tank or hydraulic lines; for example, thermocouples or thermistor sensors can be used to monitor the hydraulic oil temperature in real time. Vehicle body vibration intensity information can be obtained through accelerometers installed on the vehicle chassis or telescopic boom; a triaxial accelerometer can be used to measure the vibration acceleration of the vehicle body in different directions and calculate its intensity. Cargo sensitivity information can be manually input by the operator or obtained by identifying the cargo type through an onboard vision system and querying a preset database. Real-time fork attitude information can be obtained through angle sensors, tilt sensors, or inertial measurement units (IMUs) installed on the forks or telescopic boom; for example, a combination of MEMS gyroscopes and accelerometers can be used to provide attitude data such as fork pitch and roll angles. Next, based on the hydraulic oil temperature information, vehicle body vibration intensity information, and cargo sensitivity information, dynamic calculations are performed to obtain the fork attitude deviation tolerance. For example, a mathematical model or lookup table based on these parameters can be preset. When the hydraulic oil temperature rises, its viscosity decreases, and the hydraulic system response may become more sensitive. In this case, the attitude deviation tolerance can be tightened appropriately to avoid over-adjustment. When the vehicle body vibration intensity is high, sensor data noise may increase. In this case, the attitude deviation tolerance can be relaxed appropriately to avoid over-responding to noise. When the cargo is highly sensitive, such as when handling fragile items, a smaller attitude deviation tolerance is required to ensure cargo stability. These parameters are input into a fuzzy logic controller or neural network model, which calculates and outputs a dynamic attitude deviation tolerance value in real time. Then, the real-time attitude information of the forks is compared with the target horizontal attitude to obtain the attitude deviation. The target horizontal attitude is a preset fixed value, such as 0 degrees (completely horizontal), or a target angle dynamically set according to operational requirements. Then, when the absolute value of the attitude deviation exceeds the fork attitude deviation tolerance, a smoothing command is generated. If the calculated attitude deviation is 2 degrees, and the attitude deviation tolerance under the current operating condition is 1 degree, then the absolute value of the attitude deviation (2 degrees) exceeds the tolerance, and a smoothing command is generated. The smoothing command can be generated based on a PID control algorithm or a more complex model predictive control algorithm. Its purpose is to produce a control signal that allows the fork posture to smoothly return to the tolerance range. Finally, the fork posture is adjusted according to the smoothing command until the absolute value of the posture deviation returns to the fork posture deviation tolerance range. The smoothing command is sent to the hydraulic actuator, such as a proportional valve controlling the hydraulic cylinder, which drives the fork to make corresponding adjustments by regulating the flow and direction of the hydraulic oil. The adjustment process is continuous until the deviation between the real-time fork posture information and the target horizontal posture returns to the dynamically calculated posture deviation tolerance range.

[0072] It should be noted that obtaining the raw attitude information of the forks refers to the real-time acquisition of the forks' attitude data in three-dimensional space through attitude sensors (such as tilt sensors, gyroscopes, or accelerometers) mounted on the forks. This data may include instantaneous vibrations or swaying caused by vehicle movement, external disturbances, etc. The raw attitude information can be understood as unfiltered or unprocessed raw measurement data, the purpose of which is to comprehensively capture the motion state of the forks. Frequency analysis is performed on the raw attitude information to obtain the resonance amplitude, and resonant swaying characteristics are identified based on the resonance amplitude and a preset threshold. Frequency analysis can employ Fast Fourier Transform (FFT) or other spectral analysis methods to convert the time-domain attitude signal into a frequency-domain signal, thereby revealing the various frequency components and their corresponding amplitudes. Resonance amplitude refers to the vibration intensity of the attitude signal at a specific frequency. The preset threshold can be set based on the structural characteristics of the forklift, the natural frequency of the hydraulic system, and practical operating experience, to distinguish between normal vibration and harmful resonant swaying. When the resonance amplitude of a certain frequency component exceeds the preset threshold, the resonant swaying characteristic can be identified, the purpose of which is to accurately locate and quantify the resonance phenomenon that causes attitude instability. Furthermore, based on the identified resonant oscillation characteristics, a reverse signal is generated that is opposite to the resonant oscillation in the characteristics. Specifically, the reverse signal refers to a signal with the same frequency and amplitude as the identified resonant oscillation, but with opposite phase. Finally, the reverse signal is extracted from the original attitude information to obtain the real-time attitude information of the fork. The extraction process can be achieved by superimposing (i.e., adding) the generated reverse signal with the original attitude information. Since the reverse signal is opposite in phase to the resonant oscillation, the resonant components will be canceled out after superposition. Thus, the obtained real-time attitude information of the fork will be a more stable and accurate attitude data that has removed resonance interference, the purpose of which is to provide high-precision input for subsequent attitude deviation calculations.

[0073] It is worth noting that this application, through frequency analysis of the raw fork attitude information, can accurately identify and quantify the resonant oscillation characteristics caused by various factors. By generating inverse signals opposite to these resonant oscillations and separating them from the raw attitude information, the interference of resonance on attitude measurement is effectively eliminated. Therefore, the obtained real-time fork attitude information can more accurately reflect the actual horizontal state of the fork, providing a more reliable input for subsequent attitude deviation calculations. This processing mechanism ensures that the control system can make decisions based on real, clean attitude data, avoiding misjudgments and unnecessary adjustments caused by measurement noise or vibration.

[0074] In one embodiment, when a forklift travels on rough terrain, the forks experience a resonant oscillation with a frequency of 5 Hz and an amplitude of 0.5 degrees. First, the raw attitude information of the forks is acquired using attitude sensors mounted on the forks. Then, frequency analysis, such as Fast Fourier Transform (FFT), is performed on this raw attitude information to identify the 5 Hz resonant frequency and its 0.5-degree resonant amplitude, which are then labeled as the resonant oscillation feature. Next, based on this resonant oscillation feature, a reverse signal with a frequency of 5 Hz and an amplitude of 0.5 degrees but with opposite phase is generated. Finally, this reverse signal is superimposed on the raw attitude information, effectively canceling out the effect of the resonant oscillation and obtaining a more stable and accurate real-time attitude information for the forks without resonant components. This real-time attitude information is then used to compare with the target horizontal attitude to ensure that the control system can make adjustments based on accurate data.

[0075] It should be noted that the real-time response characteristics of a hydraulic actuator refer to the dynamic behavior of the output (e.g., flow rate, pressure, displacement, or speed) of components such as hydraulic cylinders, hydraulic valves, and hydraulic pumps over time after receiving a control command. These characteristics may include, but are not limited to, response speed, overshoot, settling time, and lag time, reflecting the actual dynamic performance of the hydraulic system under the current operating conditions. This information can be obtained by monitoring the input-output relationship of the hydraulic actuator in real time through sensors, or by estimating it through the establishment of a dynamic model. The generation parameters of the smoothing command are key parameters used to define the waveform of the smoothing command, aiming to control the smoothness and response speed of the command. The rise time of the command refers to the time required for the smoothing command to rise from its initial value to its target value. A shorter rise time usually means a faster system response, but may be accompanied by greater shocks or vibrations; while a longer rise time helps to achieve a smoother transition, but may sacrifice response speed. The fall time of the command refers to the time required for the smoothing command to fall from its target value to its initial value. Its function is similar to the rise time, mainly affecting the smoothness of the system during deceleration or stopping. The command change rate refers to the magnitude of change of a smooth command per unit time, directly reflecting the steepness of the command. A higher command change rate may cause the hydraulic system to experience greater instantaneous shocks, while a lower command change rate helps reduce shocks and makes the system operate more smoothly. Dynamically adjusting these generated parameters based on the real-time response characteristics of the hydraulic actuator means that the system adaptively modifies the rise time, fall time, and command change rate of the command according to the actual dynamic performance of the hydraulic actuator, to ensure that the generated smooth command can optimally drive the hydraulic actuator, thereby achieving precise and efficient attitude adjustment. For example, when the hydraulic actuator responds slowly, the rise time of the command can be appropriately shortened or the command change rate can be increased to speed up the response; when the hydraulic actuator responds too quickly, the rise time of the command can be appropriately extended or the command change rate can be decreased to avoid overshoot.

[0076] In one embodiment, when the forklift operates in a low-temperature environment, the hydraulic oil viscosity is high, resulting in a relatively slow response speed of the hydraulic actuator. The solution in this application acquires this slow-response characteristic information of the hydraulic actuator in real time. Based on this information, the system dynamically adjusts the generation parameters of the smoothing command. To compensate for the hysteresis of the hydraulic actuator, the command rise time may be appropriately shortened, or the command change rate may be moderately increased to ensure that the forks can respond to commands faster while maintaining stability, avoiding untimely attitude adjustment due to slow response. Conversely, if the hydraulic actuator responds quickly in a high-temperature environment or under light load conditions, the system may adjust the command parameters, such as appropriately extending the rise time or reducing the command change rate, to prevent overshoot or vibration caused by excessively fast response, thereby achieving more precise and stable attitude control.

[0077] It should be noted that obtaining real-time viscosity information of hydraulic oil refers to monitoring and acquiring the current viscosity value of the hydraulic oil in real time through sensors or other detection methods. Hydraulic oil viscosity is a crucial parameter for measuring its flow resistance, directly affecting the power loss of the hydraulic system, the response speed of the actuator, and the positioning accuracy. Real-time viscosity information aims to provide an accurate physical parameter basis for subsequent command generation. Specifically, establishing a real-time viscosity-temperature characteristic curve of hydraulic oil based on hydraulic oil temperature information and real-time viscosity information can be understood as dynamically constructing or updating the functional relationship between hydraulic oil viscosity and temperature using the hydraulic oil temperature information and newly acquired real-time viscosity information. This curve reflects the variation of hydraulic oil viscosity at different temperatures, and its purpose is to more accurately predict and compensate for the response characteristics of the hydraulic system under different operating conditions. Generating smoothing commands based on the viscosity-temperature characteristic curve refers to dynamically adjusting and optimizing the parameters of the smoothing commands based on the real-time established viscosity-temperature characteristic curve. The rise time, fall time, or command change rate of the command can be adjusted according to the current hydraulic oil viscosity to ensure that the hydraulic actuator can respond to the command with the expected speed and accuracy, thereby achieving smooth adjustment of the fork posture.

[0078] In one embodiment, when the forklift is started in a low-temperature environment, the hydraulic oil viscosity is high. First, real-time viscosity and temperature information of the hydraulic oil are acquired using viscosity and temperature sensors installed in the hydraulic circuit. The viscosity sensor can be a vibration-type or differential pressure sensor, while the temperature sensor can be a resistance temperature detector (RTD) or a thermocouple. Next, the control system uses this real-time data, combined with a pre-stored hydraulic oil viscosity-temperature data model, to continuously correct and establish the current hydraulic oil viscosity-temperature characteristic curve. When the absolute value of the fork posture deviation exceeds the tolerance, the control system queries the current viscosity-temperature characteristic curve and, based on the high viscosity characteristics of the hydraulic oil reflected in the curve, generates a smooth command with a longer rise time and a slower rate of change. If the command rise time is 0.5 seconds under normal operating conditions, it may be adjusted to 0.8 seconds under low-temperature, high-viscosity conditions to avoid sluggish response or shock in the hydraulic actuator due to excessive hydraulic oil resistance. As the forklift operates, the hydraulic oil temperature gradually rises and its viscosity decreases. The control system updates the viscosity-temperature characteristic curve in real time and adjusts the generation parameters of the smoothing command accordingly, shortening its rise time and accelerating its rate of change to meet the rapid response requirements after the hydraulic oil viscosity decreases. In this way, the generation of the smoothing command always remains consistent with the real-time physical characteristics of the hydraulic oil, ensuring the accuracy and smoothness of the fork posture adjustment.

[0079] The main points to note are: Cargo weight information refers to the total mass of goods being transported by the forklift, which can be obtained through onboard weighing sensors or preset data. Center of gravity position information refers to the coordinates of the cargo's center of gravity relative to the forks or the vehicle body. This is crucial for assessing the impact of load on vehicle stability and dynamic response and can be estimated using sensor arrays or preset models. Fork attitude change rate information refers to the rate at which the fork's attitude (e.g., pitch angle, roll angle) changes over time, reflecting the intensity and direction of the fork's current movement. This is typically measured in real-time by an inertial measurement unit (IMU) or attitude sensors.

[0080] In one embodiment, suppose the forklift needs to transport two different types of goods: the first is light palletized goods with a low center of gravity, and the second is heavy equipment with a high center of gravity. When transporting the first type of light palletized goods, the system obtains information about the weight of the goods, the low center of gravity, and the relatively small rate of change of the fork's posture. In this case, based on this information and the real-time response characteristics of the hydraulic actuator, the target generation parameters for the dynamically adjusted smoothing command may be set to a shorter rise time, a shorter fall time, and a larger command change rate. This means that the hydraulic system can adjust the fork posture at a faster speed and with a more sensitive response, thereby achieving fast and precise horizontal control. Conversely, when transporting the second type of heavy equipment with a high center of gravity, the system obtains information about the weight of the goods, the high center of gravity, and due to greater inertia, the rate of change of the fork's posture may require more careful control. In this case, the target generation parameters for the dynamically adjusted smoothing command may be set to a longer rise time, a longer fall time, and a smaller command change rate. This avoids overshoot or oscillation caused by rapid adjustments, ensuring smoother and safer attitude adjustments under heavy load and high center of gravity conditions, and effectively preventing cargo from tipping over or being damaged.

[0081] It should be noted that the dielectric constant of hydraulic oil can be obtained by installing a dielectric constant sensor in the hydraulic system, which can monitor the dielectric constant of the hydraulic oil in real time. The dielectric constant is an important parameter reflecting changes in the polar molecular content and chemical composition of the oil, and its changes are closely related to factors such as hydraulic oil oxidation, water content, and additive consumption. The target oil particle size distribution information can be obtained through an online particle counter or periodic laboratory analysis of oil samples. Particle size distribution information reveals the type, size, and quantity of solid contaminants in the hydraulic oil, which may include wear particles, external contaminants, and polymeric fracture particles generated by oil shear dilution. Assessing the degree of oxidation product accumulation in hydraulic oil based on dielectric constant information involves analyzing the trend of dielectric constant changes and combining it with the initial dielectric constant baseline value of the hydraulic oil to quantify the formation and accumulation of oxidation products. The accumulation of oxidation products typically leads to an increase in the viscosity of the hydraulic oil. Assessing the shear dilution degree of hydraulic oil based on the target oil particle size distribution information refers to determining the extent to which the polymer additives in the hydraulic oil undergo molecular chain breakage due to mechanical shearing by identifying particles of specific sizes and shapes within the particle size distribution. Shear dilution leads to a decrease in hydraulic oil viscosity.

[0082] In one embodiment, acquiring wear particle characteristic information of hydraulic oil refers to analyzing the particle size distribution information of the target oil to extract specific attributes of particles related to mechanical wear. Wear particles typically have irregular shapes, sharp edges, rough surfaces, etc., and their material characteristics may match those of mechanical components (such as metals, alloys, etc.). These characteristics can be identified using techniques such as image analysis and spectral analysis. Further, acquiring shear dilution particle characteristic information of hydraulic oil refers to identifying particles formed by the breakage of molecular chains under high-speed shearing of hydraulic oil. Shear dilution particles are typically smaller in size and may exhibit more uniform, smoother microparticles, showing a significant difference in morphology from wear particles. By comparing wear particle characteristic information and shear dilution particle characteristic information, various types of particles in the target oil particle size distribution information can be accurately identified and distinguished. Thresholds can be set or machine learning algorithms can be used to classify particles based on multiple dimensions such as shape, size, and material. Finally, based on the identified wear particles and shear dilution particles, the degree of shear dilution of the hydraulic oil can be quantitatively assessed. The degree of shear dilution can be assessed based on the number, volume percentage, or particle distribution within a specific size range of shear-diluted particles, thus obtaining an index that reflects the degree of performance degradation of hydraulic oil.

[0083] It should be noted that the initial dielectric constant information for each type of additive refers to the inherent dielectric constant values ​​of various additives (such as antioxidants, anti-wear agents, detergents, and dispersants) in new hydraulic oil before oxidation reactions occur. These values ​​can be obtained through experimental measurements or by consulting relevant technical manuals, serving as a benchmark for subsequent assessment of the degree of oxidation product accumulation. The dielectric constant variation characteristics of oxidation products refer to the influence of these oxidation products on the overall dielectric constant of the hydraulic oil when additives in the hydraulic oil undergo oxidation reactions and generate oxidation products. Specifically, different types of oxidation products have different polarities, leading to specific directional and magnitude changes in the dielectric constant of the hydraulic oil. The formation of certain polar oxidation products can significantly increase the dielectric constant of the hydraulic oil, while others may cause a decrease or minimal change. These variation characteristics can be established by measuring the dielectric constant and conducting chemical analysis on hydraulic oil samples with different degrees of oxidation. Identifying and distinguishing the contributions of different types of additive oxidation products to dielectric constant information involves analyzing the current dielectric constant of the hydraulic oil, combining it with known initial dielectric constant information of each type of additive and the dielectric constant variation characteristics of oxidation products, and using data analysis models (such as multiple regression analysis, machine learning algorithms, etc.) to decompose the total change in dielectric constant into the individual contributions caused by different types of additive oxidation products. The aim is to accurately quantify the specific impact of each oxidation product on the change in dielectric constant, thus providing a basis for subsequent quantification of accumulation levels. Quantifying the accumulation level of each type of oxidation product involves converting the identified contributions of different types of additive oxidation products to dielectric constant information, combined with a pre-set calibration curve or model, into specific oxidation product concentrations or accumulation amounts. This can be achieved by establishing a functional relationship between dielectric constant change and specific oxidation product concentrations. Superimposing the accumulation levels involves summing the quantified accumulation levels of each type of oxidation product to obtain the overall oxidation product accumulation level of the hydraulic oil. This can be achieved simply by summing, or by weighted summation based on the weight of the impact of different oxidation products on hydraulic oil performance to more accurately reflect the actual oxidation state of the hydraulic oil.

[0084] It should be noted that obtaining the raw particle size distribution information of hydraulic oil can be achieved in various ways. For example, online particle counters or offline laboratory analysis equipment can be used to test hydraulic oil samples to obtain the size, quantity, and distribution of all particles in the oil. The raw particle size distribution information reflects the overall situation of various particles contained in the hydraulic oil, including oil degradation products, wear particles, and external contaminants. Obtaining the pollution source characteristic information of hydraulic oil refers to collecting and analyzing the characteristics of external contaminants that may enter the hydraulic oil. Pollution source characteristic information can include the morphological characteristics of external environmental dust particles and the material characteristics of worn metal debris. The morphological characteristics of external environmental dust particles can include their shape (e.g., irregular, spherical), size range, and surface roughness; the material characteristics of worn metal debris can include their chemical composition (e.g., iron, copper, aluminum), hardness, and density. This characteristic information can be obtained by analyzing ambient air samples, materials of worn equipment parts, or by consulting relevant databases. Its purpose is to provide a reference standard for subsequent identification of particles from non-oil sources. Identifying non-oil-source particles in the original oil particle size distribution information and contamination source characteristic information can be achieved through data analysis and pattern recognition techniques. The particle characteristics (such as size, shape, and material) in the original oil particle size distribution information can be compared with pre-acquired contamination source characteristic information. When the particle characteristics highly match the contamination source characteristics, the particle is identified as a non-oil-source particle. Removing non-oil-source particles from the original oil particle size distribution information to obtain the target oil particle size distribution information involves filtering or eliminating these particles from the original dataset after identification. The resulting target oil particle size distribution information more accurately reflects the hydraulic oil itself and the particles generated by its internal wear, eliminating external interference factors.

[0085] In one embodiment, when a forklift is operating in an open-pit mine, the hydraulic oil in its hydraulic system is easily contaminated by a large amount of dust in the environment. When acquiring the original oil particle size distribution information of the hydraulic oil, the particle counter may detect a large number of external dust particles. The size and shape of these particles may be similar to the particles generated by internal wear of the hydraulic oil, thus confusing the judgment of the degree of oil shear dilution. This application first acquires the morphological characteristics of dust particles in the mine environment (mainly irregular silicate particles, with a size range of 1-10 micrometers). At the same time, through the analysis of the worn parts inside the hydraulic system, the material characteristics of the worn metal debris are obtained (mainly iron-based alloy particles, with a size range of 0.5-5 micrometers and a metallic luster). When analyzing the original oil particle size distribution information, the system identifies those particles that highly match the characteristics of external dust based on these pollution source characteristics and marks them as particles not originating from the oil. Subsequently, these identified non-oil-source particles are removed from the original data, thereby obtaining a target oil particle size distribution information that only contains the hydraulic oil itself and its internal wear particles. If the raw data shows a large number of irregular particles ranging from 1 to 10 micrometers, and the morphology of these particles is consistent with the characteristics of environmental dust, these particles will be removed. In this way, the subsequent assessment of the hydraulic oil shear dilution degree will no longer be affected by external dust, making the calculation of real-time viscosity information more accurate, thus providing a more reliable basis for the precise level control of forklift forks.

[0086] See Figure 2 , Figure 2 This is a schematic diagram of a forklift telescopic boom and fork synchronous horizontal control system provided in one embodiment of this application. The forklift telescopic boom and fork synchronous horizontal control system 200 includes:

[0087] The acquisition module 210 is used to acquire hydraulic oil temperature information, vehicle body vibration intensity information, cargo sensitivity information, and real-time fork attitude information.

[0088] The calculation module 220 is used to perform dynamic calculations based on hydraulic oil temperature information, vehicle vibration intensity information and cargo sensitivity information to obtain the tolerance of fork posture deviation.

[0089] The comparison module 230 is used to compare the real-time attitude information of the forks with the target horizontal attitude to obtain the attitude deviation;

[0090] The instruction generation module 240 is used to generate a smooth instruction when the absolute value of the attitude deviation exceeds the tolerance of the fork attitude deviation.

[0091] The adjustment module 250 is used to adjust the fork posture according to the smoothing command until the absolute value of the posture deviation returns to the range of the fork posture deviation tolerance.

[0092] It should be noted that the information interaction and execution process between the above modules are based on the same concept as the method embodiments of this application. For details on their specific functions and technical effects, please refer to the method embodiments section, which will not be repeated here.

[0093] It will be understood by those skilled in the art that all or some of the steps and systems in the methods disclosed above can be implemented as software, firmware, hardware, and suitable combinations thereof. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, as is known to those skilled in the art, communication media typically include computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0094] The foregoing has provided a detailed description of the preferred embodiments of this application. However, this application is not limited to the above-described embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of this application. All such equivalent modifications or substitutions are included within the scope defined in this application.

Claims

1. A method for synchronously controlling the horizontal movement of a forklift's telescopic boom and forks, characterized in that, include: Acquire information on hydraulic oil temperature, vehicle vibration intensity, cargo sensitivity, and real-time fork attitude. The tolerance for fork posture deviation is obtained by dynamically calculating based on the hydraulic oil temperature information, the vehicle body vibration intensity information, and the cargo sensitivity information. The real-time attitude information of the forks is compared with the target horizontal attitude to obtain the attitude deviation; When the absolute value of the attitude deviation exceeds the tolerance of the fork attitude deviation, a smoothing command is generated; The fork posture is adjusted according to the smoothing command until the absolute value of the posture deviation returns to the range of the fork posture deviation tolerance.

2. The method according to claim 1, characterized in that, The real-time attitude information of the forks is obtained through the following steps: Obtain the original posture information of the forks; Frequency analysis is performed on the original attitude information to obtain the resonance amplitude, and the resonance oscillation characteristics are identified based on the resonance amplitude and a preset threshold. Based on the identified resonant oscillation characteristics, an inverse signal opposite to the resonant oscillation in the resonant oscillation characteristics is generated; The reverse signal is extracted from the original attitude information to obtain the real-time attitude information of the fork.

3. The method according to claim 1, characterized in that, When the absolute value of the attitude deviation exceeds the tolerance of the fork attitude deviation, a smoothing instruction is generated, including: When the absolute value of the attitude deviation exceeds the tolerance of the fork attitude deviation, the real-time response characteristic information of the hydraulic actuator is obtained; Based on the real-time response characteristics of the hydraulic actuator, the generation parameters of the smoothing command are dynamically adjusted to obtain the target generation parameters, wherein the generation parameters include the rise time, fall time, and rate of change of the command. A smoothing instruction is generated based on the target generation parameters.

4. The method according to claim 1, characterized in that, When the absolute value of the attitude deviation exceeds the tolerance of the fork attitude deviation, a smoothing instruction is generated, including: When the absolute value of the attitude deviation exceeds the tolerance of the fork attitude deviation, the real-time viscosity information of the hydraulic oil is obtained; Based on the hydraulic oil temperature information and the real-time viscosity information, a viscosity-temperature characteristic curve of the hydraulic oil is established in real time. Based on the viscosity-temperature characteristic curve, a smoothing instruction is generated.

5. The method according to claim 3, characterized in that, The step of dynamically adjusting the generation parameters of the smoothing command based on the real-time response characteristic information of the hydraulic actuator to obtain the target generation parameters includes: Acquire information on the weight of the goods, the position of the center of gravity, and the rate of change of the fork's posture; Based on the weight information of the cargo, the center of gravity position information, the attitude change rate information of the forks, and the real-time response characteristic information of the hydraulic actuator, the generation parameters of the smoothing command are dynamically adjusted to obtain the target generation parameters.

6. The method according to claim 4, characterized in that, The real-time viscosity information of the hydraulic oil is obtained through the following steps: Obtain the dielectric constant information of the hydraulic oil; Obtain target oil particle size distribution information for hydraulic oil; Based on the dielectric constant information, assess the degree of oxidation product accumulation in the hydraulic oil; The degree of shear dilution of the hydraulic oil is evaluated based on the target oil particle size distribution information. The real-time viscosity information of the hydraulic oil is obtained based on the degree of accumulation of the oxidation products and the degree of shear dilution.

7. The method according to claim 6, characterized in that, The step of evaluating the shear dilution degree of the hydraulic oil based on the target oil particle size distribution information includes: The wear particle characteristic information of hydraulic oil is obtained based on the target oil particle size distribution information, wherein the wear particle characteristic information includes the shape characteristics and material characteristics of the wear particles; Based on the target oil particle size distribution information, the shear dilution particle characteristic information of the hydraulic oil is obtained, wherein the shear dilution particle characteristic information includes the size range and morphological characteristics of the shear dilution particles; Based on the wear particle characteristic information and the shear dilution particle characteristic information, identify and distinguish wear particles and shear dilution particles in the target oil particle size distribution information; The degree of shear dilution of the hydraulic oil is assessed based on the wear particles and the shear dilution particles.

8. The method according to claim 6, characterized in that, The step of assessing the degree of oxidation product accumulation of the hydraulic oil based on the dielectric constant information includes: Obtain initial dielectric constant information and dielectric constant variation characteristics of oxidation products for various types of additives in hydraulic oil; Based on the dielectric constant information, the initial dielectric constant information of each type of additive, and the dielectric constant change characteristics of the oxidation products, the contribution values ​​of the oxidation products of different types of additives to the dielectric constant information are identified and distinguished. The accumulation degree of each type of oxidation product is quantified based on the identified contribution value, and the accumulation degree is superimposed to obtain the accumulation degree of oxidation products of the hydraulic oil.

9. The method according to claim 8, characterized in that, The acquisition of target oil particle size distribution information for hydraulic oil includes: Obtain the original oil particle size distribution information of the hydraulic oil; Obtain the pollution source characteristic information of hydraulic oil, including the morphological characteristics of dust particles in the external environment and the material characteristics of worn metal debris; Based on the original oil particle size distribution information and the pollution source characteristic information, identify particles from non-oil sources in the original oil particle size distribution information; The target oil particle size distribution information is obtained by removing particles from the original oil particle size distribution information that are not from oil.

10. A synchronous horizontal control system for the telescopic boom and forks of a forklift, characterized in that, include: The acquisition module is used to acquire hydraulic oil temperature information, vehicle body vibration intensity information, cargo sensitivity information, and real-time fork attitude information. The calculation module is used to dynamically calculate the fork posture deviation tolerance based on the hydraulic oil temperature information, the vehicle body vibration intensity information, and the cargo sensitivity information. The comparison module is used to compare the real-time attitude information of the forks with the target horizontal attitude to obtain the attitude deviation; The instruction generation module is used to generate a smooth instruction when the absolute value of the attitude deviation exceeds the tolerance of the fork attitude deviation. The adjustment module is used to adjust the posture of the forks according to the smoothing command until the absolute value of the posture deviation returns to the range of the fork posture deviation tolerance.

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