Method and device for measuring rotational inertia of suspension mass of tractor and related equipment

Abstract

The invention relates to the technical field of vehicle testing, in particular to a method and device for measuring rotational inertia of suspension mass of a tractor and related equipment. The method is applied to a tractor, a balanced suspension is arranged on the tractor, and the suspension mass of the tractor can perform pitching vibration around a suspension mandrel of the balanced suspension. The method comprises the following steps: determining the leaf spring rigidity of a leaf spring on a tractor through the movement of a tractor head on the tractor; the vibration frequency of the suspension mass is determined through vibration of a vehicle head; wherein the vibration frequency of the suspension mass is the vibration degree of the suspension mass when the suspension mass rotates around the axis of the balanced suspension mandrel; determining the rotational inertia of the suspension mass of the tractor according to the leaf spring rigidity and the vibration frequency; the technical problem that in the prior art, an estimation method for rotational inertia is large in error can be solved.

Description

Technical Field

[0001] The present application relates to the field of vehicle testing technology, and in particular to a method, device and related equipment for measuring the moment of inertia of the suspension mass of a tractor. Background Art

[0002] In the process of designing and evaluating the performance of tractor vehicles (trucks), it is necessary to determine the moment of inertia of the suspended mass of the cargo vehicle around the axis of the balanced suspension spindle through experimental measurement or numerical simulation methods; among them, the suspended mass is usually used to refer to the sum of the parts of the cargo vehicle including the frame, body, engine, transmission system, passengers and cargo, and the moment of inertia is a measure of the difficulty of the cargo vehicle to resist changing its rotational state.

[0003] In the existing technical solutions for measuring the moment of inertia of the suspended mass of a cargo vehicle around the axis of the balanced suspension spindle, the measurement is usually carried out by simulation, that is, by fixing the suspended mass at one end of the torsion pendulum, allowing it to rotate freely around the axis of the balanced suspension spindle, and then measuring the period of the torsion pendulum. According to the torsion pendulum period and relevant parameters of the torsion pendulum device (such as the moment of inertia of the torsion pendulum, the suspended mass, the length of the torsion pendulum, etc.), the moment of inertia of the suspended mass can be approximately estimated.

[0004] According to practical experience, the above-mentioned estimation method for the moment of inertia has the disadvantage of large errors. Summary of the invention

[0005] In view of this, the purpose of the present application is to provide a method, device and related equipment for measuring the moment of inertia of the suspension mass of a tractor, so as to solve the technical problem that the estimation method for the moment of inertia in the prior art has the disadvantage of large errors.

[0006] In a first aspect, the present application provides a method for measuring the moment of inertia of a tractor suspension mass, which is applied to a tractor, wherein the tractor is provided with a balancing suspension, and the tractor suspension mass can perform pitch vibration around a suspension spindle of the balancing suspension; the method comprises: Determining the leaf spring stiffness of the leaf spring on the tractor by moving the head of the tractor; Determining the vibration frequency of the suspended mass by the vibration of the front of the vehicle; The vibration frequency of the suspended mass is the vibration degree of the suspended mass when it rotates around the axis of the balance suspension spindle; The moment of inertia of the suspended mass of the tractor vehicle is determined based on the leaf spring stiffness and the vibration frequency.

[0007] In a second aspect, the present application provides a rotational inertia measuring device for a tractor suspension mass, which is applied to a tractor, wherein the tractor is provided with a balancing suspension, and the tractor suspension mass can perform pitch vibration around a suspension spindle of the balancing suspension; the device comprises: a stiffness measuring module, a frequency measuring module and an inertia measuring module; The stiffness determination module is used to determine the leaf spring stiffness of the leaf spring on the tractor by moving the head of the tractor; The frequency determination module is used to determine the vibration frequency of the suspended mass through the vibration of the vehicle head; wherein the vibration frequency of the suspended mass is the vibration degree of the suspended mass when it rotates around the axis of the balance suspension spindle; The inertia determination module is used to determine the rotational inertia of the suspended mass of the tractor according to the leaf spring stiffness and the vibration frequency.

[0008] In a third aspect, the present application provides an electronic device, comprising a processor and a memory, wherein the memory is used to store an application program, and the processor runs or executes a software program stored in the memory so that the electronic device implements the above-mentioned method for measuring the moment of inertia of the suspension mass of a tractor.

[0009] In a fourth aspect, the present application provides a computer-readable storage medium, wherein the computer-readable storage medium is used to store program codes executed by a processor, wherein the program codes are used to implement the above-mentioned method for measuring the moment of inertia of the suspended mass of a tractor.

[0010] In a fifth aspect, the present application provides a computer program product, which includes computer instructions. When the computer instructions are run on an electronic device, the electronic device implements the above-mentioned method for measuring the moment of inertia of the suspension mass of a tractor.

[0011] Beneficial effects: The present application provides a method for measuring the moment of inertia of the suspended mass of a tractor, the method comprising: determining the leaf spring stiffness of the leaf spring on the tractor by moving the head of the tractor; determining the vibration frequency of the suspended mass by vibrating the head of the tractor; wherein the vibration frequency of the suspended mass is the vibration degree of the suspended mass when the suspended mass rotates around the axis of the balance suspension spindle; determining the moment of inertia of the suspended mass of the tractor according to the leaf spring stiffness and the vibration frequency; In summary, unlike the estimation method adopted in the prior art, the present application first directly measures the load-bearing and deformation relationship of the leaf spring on the tractor by moving the front of the vehicle, thereby determining the stiffness of the leaf spring, avoiding errors caused by estimation, and ensuring the accuracy of the leaf spring stiffness data; in addition, the present application ensures the accuracy of the vibration frequency data by directly measuring the vibration frequency of the suspended mass when it is subjected to pitch vibration around the axis of the balancing suspension spindle on the tractor; in addition, after obtaining the leaf spring stiffness and vibration frequency, the present application can calculate the moment of inertia of the suspended mass of the tractor around the axis of the balancing suspension spindle according to the leaf spring stiffness and vibration frequency. Due to the accuracy of the first two steps of measurement, the moment of inertia finally calculated also has a high accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. The following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0013] Figure 1 A schematic flow chart of a method for measuring the moment of inertia of the suspension mass of a tractor provided in an embodiment of the present application; Figure 2 A schematic diagram of the structure of a tractor provided in an embodiment of the present application; Figure 3 A schematic diagram of a stress-strain curve of a leaf spring provided in an embodiment of the present application; Figure 4 A schematic diagram of a vibration spectrum curve of a suspended mass provided in an embodiment of the present application; Figure 5 A schematic diagram of the structure of a device for measuring the moment of inertia of the suspension mass of a tractor provided in an embodiment of the present application. DETAILED DESCRIPTION

[0014] In vehicle design and performance evaluation, in many cases, it is necessary to determine the moment of inertia of the suspended mass around the axis of the balanced suspension spindle through experimental measurement or numerical simulation. The moment of inertia, also known as the moment of inertia, is a physical quantity that describes the inertial characteristics of a rigid body when it rotates around an axis. It is used to measure the difficulty of an object in resisting changes in its rotational state. The size of the moment of inertia is closely related to the shape of the object, the mass distribution, and the position of the rotation axis.

[0015] In actual operation, existing technical solutions for measuring the rotational inertia of the suspended mass of a cargo vehicle mostly use simulation methods, that is, fixing the suspended mass at one end of the pendulum to allow it to rotate freely, and estimating the rotational inertia by measuring the pendulum period and combining the pendulum device parameters. However, this method has the disadvantage of large errors.

[0016] In order to solve the above technical problems, the present application provides a solution for measuring the moment of inertia of the suspended mass of a tractor. The technical solution first determines the stiffness of the leaf spring by moving the front of the tractor, and then accurately measures the stiffness of the leaf spring to provide basic data for the subsequent calculation of the moment of inertia of the suspended mass. In addition, the technical solution also determines the vibration frequency of the suspended mass by the vibration of the front of the vehicle. The vibration frequency can indicate the degree of vibration of the suspended mass when it rotates around the axis of the balance suspension core shaft, and directly reflects the dynamic characteristics of the suspended mass. Accurately measuring the vibration frequency is a key step in calculating the moment of inertia because it is directly related to the moment of inertia of the suspended mass. Finally, the moment of inertia is calculated in combination with the leaf spring stiffness and the vibration frequency. Since the technical solution is actually measured on the tractor without measuring the suspended mass, the technical solution completely avoids the error sources in the traditional simulation method, thereby improving the accuracy of the moment of inertia measurement.

[0017] In summary, since the technical solution accurately measures the leaf spring stiffness and the vibration frequency of the suspended mass and combines the two to calculate the moment of inertia, it can effectively solve the problem of large errors in measuring the moment of inertia of the suspended mass of a cargo vehicle in the prior art.

[0018] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution of the present application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present application.

[0019] First, the present application provides a method for measuring the moment of inertia of the suspension mass of a tractor, which is applied to a tractor, wherein a balancing suspension is provided on the tractor, and the suspension mass of the tractor can perform pitch vibration around the suspension spindle of the balancing suspension; Figure 1 As shown, Figure 1 A flow chart of a method for measuring the moment of inertia of the suspension mass of a tractor provided in an embodiment of the present application, the method comprising: S110 to S130, the details of which are as follows: S110: Determine the leaf spring stiffness of the leaf spring on the tractor by moving the front of the tractor.

[0020] Specifically, Figure 2 As shown, Figure 2This is a schematic diagram of the structure of a tractor provided in an embodiment of the present application. The leaf spring used in the embodiment of the present application for measuring the moment of inertia of the suspended mass is a leaf spring under the front of the vehicle.

[0021] In this step, the leaf spring is deformed by controlling the front of the tractor to move. The leaf spring stiffness is calculated by measuring the stress or strain of the leaf spring under a specific deformation and combining the material properties and geometric dimensions of the leaf spring. The leaf spring stiffness is an important parameter of the suspended mass and has a direct impact on the vibration characteristics of the suspended mass. Therefore, accurate measurement of the leaf spring stiffness is the basis for the subsequent calculation of the moment of inertia.

[0022] In one implementation, S110 includes: Step (1) to Step (3), the details of which are as follows: Step (1): Control the front end of the stationary tractor to lift it from its current position to a preset height.

[0023] Specifically, before performing the lifting operation, it is necessary to confirm that the tractor has completely stopped and is in a stable parking state. This can be achieved by checking whether the vehicle's brake system is reliably locked and whether there is sufficient support around the vehicle to prevent it from moving accidentally. To ensure safety, obvious warning signs should also be set up around the lifting area, and non-operating personnel should be prohibited from entering to prevent accidents. In actual operation, it is necessary to select a gantry truck or other lifting equipment that can safely and stably lift the front of the vehicle. The selection of lifting equipment should be based on the weight of the tractor, the front structure, and the requirements of the lifting height. Before using the lifting equipment, it should be fully inspected to ensure that all components (such as hooks, wire ropes, brake systems, etc.) are in good condition and meet safety standards.

[0024] The preset height should be precisely determined based on the structural characteristics of the tractor, the location of the leaf springs and the convenience of measurement. Generally, this height should be high enough to clearly observe the deformation of the leaf springs and facilitate relevant measurements or evaluations. When setting the preset height, the bearing capacity of the suspension mass and the safety of other components must be fully considered. Excessive lifting may cause damage to the suspension mass or other components, so ensure that the lifting height is within a safe range.

[0025] During the lifting process, the front of the vehicle should be lifted slowly and steadily to avoid sudden acceleration or deceleration that may cause vehicle shaking or component damage. When the front of the vehicle is lifted to a height close to the preset height, the position and height of the lifting equipment should be adjusted with special care to ensure that the front of the vehicle can stay accurately and stably at the preset position.

[0026] When the front of the vehicle is safely lifted to the preset height, the suspended mass of the tractor should be slowly rotated around the suspension spindle of the balancing suspension. During the rotation process, the deformation of the leaf spring should be closely observed. It is a normal physical phenomenon that the leaf spring will produce a certain degree of tensile or compressive deformation. However, it should be ensured that the deformation is within the elastic working range to avoid exceeding the elastic limit of the material and causing plastic deformation or damage.

[0027] In actual operation, if the leaf spring deformation is found to be abnormal or beyond the expected range, the rotation should be stopped immediately and the cause should be checked. If necessary, the hoisting height should be adjusted or other measures should be taken to ensure the accuracy and safety of the measurement.

[0028] In summary, step (1) is an important part of the measurement process of the moment of inertia of the tractor suspension mass. It is necessary to strictly control the operation process, ensure that the tractor is in a stationary and stable state, select appropriate lifting equipment, accurately determine the preset height, and closely observe the deformation of the leaf spring. Through the above measures, the accuracy and safety of the measurement can be ensured, providing reliable data support for the subsequent measurement process of the moment of inertia of the suspension mass.

[0029] Step (2): Control the front of the vehicle to move downward from a preset height at a preset speed and measure the deformation of the leaf spring in the vertical direction and the load-bearing capacity of the leaf spring during the movement.

[0030] Specifically, during the execution of step (2), it is necessary to ensure that the lifting equipment can lower the front of the vehicle in a stable and controllable manner, and at the same time, it is necessary to prepare instruments for measuring the deformation and load-bearing capacity of the leaf spring, such as an electronic scale and a height gauge; wherein the electronic scale can be set on the lower side of the middle part of the leaf spring, and a bracket can be set between the electronic scale and the leaf spring.

[0031] In actual operation, as the front of the vehicle descends, the leaf spring is subjected to increasing pressure, causing the deformation and load-bearing capacity to gradually increase. During the above process, the electronic scale and height gauge will record the deformation and load-bearing capacity of the leaf spring in real time.

[0032] It should be emphasized that the selection of the preset speed should take into account the deformation speed and measurement accuracy of the leaf spring, and a slower speed is usually selected to ensure the accuracy of the measurement data. Among them, the preset speed can be calculated by establishing a physical model of the tractor suspension mass and using the dynamic equation. This method requires an accurate understanding of the physical parameters of the system, such as mass, stiffness, damping, etc.; in addition, an empirical formula between the preset speed and other physical quantities (such as vibration frequency, stiffness, etc.) can be fitted through a large amount of experimental data. This method relies on the accuracy and extensiveness of the experimental data; in addition, historical data can be collected and analyzed to find the optimal value or range of the preset speed.

[0033] Through step (2), the bearing weight data of the leaf spring under different deformation states can be obtained, which provides reliable experimental data for the subsequent calculation of the leaf spring stiffness. In actual operation, step (2) is also helpful to evaluate the performance and stability of the leaf spring under different working conditions.

[0034] Step (3): Determine the leaf spring stiffness of the leaf spring based on the deformation and the load-bearing capacity.

[0035] Specifically, in the embodiments of the present application, the leaf spring stiffness is a physical quantity that describes the leaf spring's ability to resist deformation under force, and is usually expressed as the amount of deformation produced by the leaf spring per unit length when subjected to a unit force. The greater the stiffness, the smaller the leaf spring's deformation when subjected to force, and the stronger its ability to resist deformation.

[0036] In the embodiment of the present application, the deformation of the leaf spring under different loads is obtained by experimental measurement, and the stress-strain curve of the leaf spring can be drawn. Figure 3 As shown, Figure 3 A schematic diagram of a stress-strain curve of a leaf spring provided in an embodiment of the present application, Figure 3 The horizontal axis represents the deformation variable. Figure 3 The vertical axis represents the load-bearing capacity. The curve reflects the relationship between stress and strain of the leaf spring during the force-bearing process and is an important basis for evaluating the performance of the leaf spring.

[0037] The drawing of stress-strain curve requires accurate experimental data, including the load and the corresponding deformation. Through the precise measurement of the experimental equipment, the above data can be obtained and the curve can be drawn. After the stress-strain curve is obtained, the curve can be processed by linear regression analysis or other mathematical methods to calculate the stiffness of the leaf spring.

[0038] Linear regression analysis is a commonly used mathematical method that can approximate the stress-strain curve by fitting a straight line to obtain the stiffness value of the leaf spring. In addition to linear regression analysis, other mathematical methods such as polynomial fitting and exponential fitting can also be considered. The most appropriate method can be selected according to the specific situation of the experimental data.

[0039] Among them, the leaf spring stiffness The calculation formula is as follows: ; in, The stress-strain curve The slope of a data set; the data set can be any two data points in the stress-strain curve; Indicates the total number of data groups.

[0040] In actual operation, the experimental data needs to be analyzed and processed in detail. This includes steps such as data cleaning, denoising, and normalization to ensure the accuracy and reliability of the data. By analyzing the experimental data, the deformation of the leaf spring under different loads can be obtained, and then the stiffness value of the leaf spring can be calculated. The stiffness values ​​under different deformation states can also be compared to evaluate the stiffness and elastic properties of the leaf spring.

[0041] The leaf spring stiffness value obtained in step (3) is an important parameter for the subsequent calculation of the moment of inertia of the tractor suspension mass around the center of the balanced suspension spindle. The calculation of the moment of inertia needs to consider the rigidity and mass distribution of the suspension mass, and the leaf spring stiffness is one of the key factors.

[0042] In addition, leaf spring stiffness also provides an important basis for the design, optimization and simulation analysis of tractor suspension quality. When designing suspension quality, it is necessary to select the appropriate leaf spring stiffness based on factors such as vehicle driving conditions and load requirements to ensure the performance and reliability of suspension quality.

[0043] In optimization and simulation analysis, leaf spring stiffness is also an important input parameter. By adjusting the leaf spring stiffness value, the performance of different suspension masses can be simulated, providing strong support for vehicle design and improvement.

[0044] In summary, step (3) is the key link to evaluate the performance of leaf springs, optimize the suspension mass design, and calculate the moment of inertia. Through accurate experimental measurement and data analysis, the stiffness value of the leaf spring can be obtained, providing important parameter basis for subsequent calculations and analysis.

[0045] In summary, through the detailed operations of steps (1) to (3), the stiffness of the leaf spring on the tractor can be accurately measured, providing reliable experimental data and theoretical basis for the subsequent calculation of the moment of inertia. This method not only improves the accuracy of the measurement, but also provides strong support for the design and optimization of the tractor suspension quality.

[0046] In one implementation, before S110, the method further includes: Step (4) to Step (6), the details of which are as follows: Step (4): Predict the suspension mass to obtain the predicted mass.

[0047] Specifically, in the embodiment of the present application, during the measurement of the rotational inertia of the tractor suspension mass, in order to more accurately determine the stiffness of the leaf spring, it is necessary to predict the suspension mass before the measurement and adjust the measurement parameters, such as the preset height, according to the prediction results.

[0048] In actual operation, basic information of the tractor is collected, including but not limited to historical data of the vehicle such as the model. Based on the historical data, a correlation model between the suspension quality and factors such as the model and configuration is established. Through this model, the suspension quality of the tractor can be predicted according to the configuration of the current tractor; the historical data refers to the historical suspension quality and historical preset height of the tractor.

[0049] In addition, the suspension mass can be estimated by combining the structural characteristics of the tractor with the principles of physics. For example, the approximate value of the suspension mass can be calculated based on factors such as the total mass of the vehicle, the distribution of the front and rear axle loads, and the geometric dimensions of the suspension mass.

[0050] For example, suppose the model and suspension configuration of the tractor are known. By consulting the data provided by the manufacturer, it is known that the suspension mass of this model with similar configuration is about 5 tons. At the same time, according to the physical model estimation, the suspension mass of this model is also about 5 tons. Therefore, it can be predicted that the current tractor suspension mass is 5 tons.

[0051] Step (5): According to the predicted quality, determine the current quality level to which the predicted quality belongs from a plurality of candidate quality levels.

[0052] Specifically, in the embodiment of the present application, the tractor suspension mass is divided into a plurality of mass gears according to the possible range of the tractor suspension mass. For example, it can be set to gears such as less than 3 tons, 3-5 tons, 5-7 tons, and more than 7 tons. The predicted mass is matched with the divided mass gears to determine the current mass gear to which the predicted mass belongs. Now, taking the predicted mass of 5 tons as an example, in the divided mass gears, 5 tons belongs to the gear range of 5-7 tons, so it can be determined that the current mass gear of the suspension mass is 5-7 tons.

[0053] In actual operation, accurate determination of the division intervals can be used to more accurately control vehicle performance, optimize suspension quality design, or meet different transportation needs. Therefore, it is necessary to formulate the division criteria as accurately as possible to ensure that the interval division meets actual needs. First, it is necessary to analyze the overall range of the suspension quality of tractors corresponding to different models in daily situations, usually including the quality of the vehicle when it is unloaded, the quality when it is fully loaded, and possible overload conditions. By analyzing the quality range, the number and approximate range of the intervals can be preliminarily determined.

[0054] After the number and approximate range of intervals are preliminarily determined, specific division standards can be formulated based on the mass range. The above standards can be based on specific weight values, or on a certain ratio or relative value. For example, you can choose to divide the mass range into several intervals, or formulate division standards based on factors such as the design load of the tractor and the actual use scenario; when formulating division standards, you also need to consider the convenience and operability in actual application. The number of intervals should not be too many or too few. Too many will increase the difficulty of management, and too few may not meet actual needs; the range of intervals should cover all possible situations of the tractor suspension mass as much as possible to ensure that each mass value can find a corresponding interval.

[0055] After the division criteria are established, they need to be verified and adjusted. The rationality and accuracy of the intervals can be verified by actually measuring the suspension mass of the tractor and comparing it with the division intervals. If the interval division is found to be unreasonable or inaccurate, it needs to be adjusted and optimized in a timely manner.

[0056] Step (6): Determine the preset height of the suspended mass according to the corresponding relationship between the mass level and the preset height and the current mass level.

[0057] Specifically, based on experimental experience and theoretical analysis, a corresponding relationship between mass level and preset height is established, and the corresponding relationship can be determined according to the characteristics of the suspended mass and the measurement requirements. Based on the current mass level and the established corresponding relationship, a preset height suitable for the suspended mass is determined.

[0058] For example, assume that in the experiment, the following correspondence between mass levels and preset heights has been established: below 3 tons corresponds to preset height A, 3-5 tons corresponds to preset height B, 5-7 tons corresponds to preset height C, and above 7 tons corresponds to preset height D. Since the current mass level of the suspended mass is 5-7 tons, the preset height can be determined to be C.

[0059] Through the operations of step (4) to step (6), the measurement parameters (such as preset height) can be adjusted according to the predicted results of the tractor suspension mass, so as to more accurately measure the stiffness of the leaf spring and provide reliable data support for the subsequent calculation of the moment of inertia. This method not only improves the accuracy of the measurement, but also enhances the flexibility and applicability of the measurement.

[0060] S120: determining the vibration frequency of the suspended mass through the vibration of the front of the vehicle; The vibration frequency of the suspended mass is the degree of vibration of the suspended mass when it rotates around the axis of the balance suspension spindle.

[0061] Specifically, this step controls the front of the vehicle to generate vibration, thereby driving the suspended mass to rotate around the axis of the balance suspension spindle. Vibration signals of the suspended mass are collected in real time using measuring equipment such as vibration sensors or accelerometers. The vibration frequency of the suspended mass is extracted by performing spectrum analysis on the vibration signal. The vibration frequency reflects the degree of vibration of the suspended mass during the rotation process and is a key parameter for calculating the moment of inertia.

[0062] In one implementation, S120 includes: step (7) to step (8), the details of which are as follows: Step (7): Control the front end of the tractor vehicle in a stationary state to vibrate so that the suspended mass vibrates within a preset amplitude and measure vibration data of the suspended mass during the vibration process.

[0063] Specifically, during the execution of step (7), the tractor is placed in a stationary state to ensure the stability of the vehicle; in actual operation, a hydraulic or electric device is used to control the head of the vehicle to vibrate up and down, and the vibration amplitude is set according to a preset amplitude. During the vibration process, a vibration sensor or accelerometer is installed on the bottom side of the head of the vehicle to collect vibration data in real time.

[0064] For example, when the tractor is unloaded, the preset amplitude can be 5 cm. The control device makes the front of the vehicle vibrate up and down in the form of a sine wave with a frequency of 1 Hz. The vibration sensor records the acceleration change of the suspended mass in real time; when the tractor is fully loaded, the preset amplitude can be 11 cm.

[0065] Step (8): Determine the vibration frequency of the suspended mass in the vertical direction based on the vibration data.

[0066] Specifically, the collected vibration data is preprocessed to remove noise and outliers. The vibration data is processed using spectrum analysis methods such as fast Fourier transform (FFT) to obtain a vibration spectrum curve, such as Figure 4 As shown, Figure 4 It is a schematic diagram of a vibration spectrum curve of a suspended mass provided in an embodiment of the present application. The main vibration frequency peak is determined in the vibration spectrum curve, that is, the vibration frequency of the suspended mass in the vertical direction.

[0067] In actual operation, the collected acceleration data is processed by FFT (Fast Fourier Transform) to obtain the vibration spectrum curve. In the spectrum curve, the main vibration frequency peak appears at 2.5Hz, so the vibration frequency of the suspended mass is determined to be 2.5Hz.

[0068] Among them, the vibration frequency The calculation formula is as follows: ; ; In the formula, represents the vibration period of the tractor's suspended mass; The vibration spectrum curve The period of each data set; Indicates the total number of data groups; a data group can be the duration between two adjacent peaks and troughs in the vibration spectrum curve.

[0069] In one implementation, before S120, the method further includes: step (9) to step (11), the details of which are as follows: Step (9): Predict the suspension mass to obtain the predicted mass.

[0070] Step (10): According to the predicted quality, determine the current quality level to which the predicted quality belongs from a plurality of candidate quality levels.

[0071] Specifically, the contents of step (9) to step (10) can refer to the description of step (4) to step (5).

[0072] Step (11): Determine the preset amplitude of the suspended mass according to the corresponding relationship between the mass level and the preset amplitude and the current mass level.

[0073] Specifically, the mass level is a classification indicator that describes the mass borne by the suspension mass, which is usually divided according to the vehicle's load or the design load-bearing capacity of the suspension mass. The preset amplitude refers to the vibration amplitude expected to be achieved by the suspension mass under a specific excitation. The amplitude directly affects the vehicle's driving stability, ride comfort and durability of the suspension mass.

[0074] The correspondence between the mass gear and the preset amplitude is established to ensure that the suspension mass can maintain appropriate vibration characteristics at different mass gears, neither excessive vibration nor too stiff. When establishing the correspondence between the mass gear and the preset amplitude, the principle of "the lower the mass gear, the larger the preset amplitude; the higher the mass gear, the smaller the preset amplitude" is usually followed. This is because when the mass borne by the suspension mass is small, in order to maintain sufficient sensitivity and responsiveness, a larger amplitude needs to be set to ensure that the suspension mass can effectively absorb and buffer vibration. When the mass borne by the suspension mass is large, in order to maintain the stability and safety of the vehicle, the amplitude needs to be reduced to avoid excessive vibration and damage to the suspension mass.

[0075] In actual operation, it is first necessary to accurately obtain the mass borne by the suspended mass through sensors or other measuring equipment and determine the current mass level according to the preset mass level classification standard. After the current mass level is determined, the preset amplitude corresponding to the mass level can be found according to the previously established correspondence. For example, if the current mass level is 2-4 tons, then according to the correspondence, the preset amplitude should be 5 cm.

[0076] The preset amplitude determined will serve as a reference standard in the performance test, tuning and actual control of the suspension mass. In the performance test, the difference between the actual amplitude and the preset amplitude can be compared to evaluate whether the performance of the suspension mass meets the design requirements. In the tuning process, the preset amplitude can be adjusted according to actual needs to optimize the vibration characteristics of the suspension mass. In actual control, the preset amplitude can be used as a control target, and the amplitude can be accurately controlled by adjusting the parameters of the suspension mass (such as damping force, stiffness, etc.).

[0077] For example, different suspension masses correspond to different mass levels, and each mass level corresponds to a preset amplitude. When the vehicle is unloaded (low mass level), the preset amplitude of the suspension mass is set to a larger value (such as 5cm) to ensure that the vehicle can maintain good ride comfort and driving stability when encountering bumpy roads. When the vehicle is fully loaded (high mass level), the preset amplitude of the suspension mass is set to a smaller value (such as 2cm) to avoid excessive vibration that may cause damage to the vehicle and cargo.

[0078] In summary, step (11) provides an important reference standard for performance testing, tuning and actual control of the suspension mass by establishing a corresponding relationship between the mass gear and the preset amplitude and determining the preset amplitude suitable for the suspension mass according to the current mass gear.

[0079] S130: Determine the moment of inertia of the suspended mass of the tractor according to the leaf spring stiffness and the vibration frequency.

[0080] Specifically, this step combines the leaf spring stiffness and the vibration frequency of the suspended mass measured previously, and uses a dynamic equation or an empirical formula to calculate the moment of inertia of the suspended mass. The dynamic equation can be established based on the physical model and mechanical principles of the suspended mass, and the empirical formula can be obtained by fitting experimental data. By substituting the measured leaf spring stiffness and vibration frequency into the equation or formula, the moment of inertia of the suspended mass is solved.

[0081] In one implementation, S130 includes: step (12), details of which are as follows: Step (12): Determine the moment of inertia of the suspended mass according to the leaf spring stiffness, vibration frequency and moment of inertia calculation formula; The calculation formula for the moment of inertia is as follows:

[0082] In the formula, Indicates the suspended mass of the tractor; It indicates the distance between the longitudinal center point of the leaf spring and the center of the balance suspension spindle; Indicates the leaf spring stiffness; Indicates the vibration frequency.

[0083] Specifically, during step (12), it is necessary to ensure that the leaf spring stiffness has been accurately measured and recorded. , vibration frequency And the distance between the longitudinal center point of the leaf spring and the axis of the balance suspension spindle In actual operation, after the calculation is completed, the results need to be checked to determine whether they are reasonable and whether they conform to physical reality.

[0084] If the result is abnormal, such as the moment of inertia is too large or too small, the accuracy of the measured data and the correctness of the formula should be checked. Possible reasons include measurement errors, data recording errors, or improper use of formulas. If the result is abnormal, the accuracy of the measured data should be checked first. This can be verified by repeating the measurement, using different measuring equipment or methods.

[0085] The determined moment of inertia will be an important parameter for the dynamic analysis of the suspension mass, which can be used to evaluate the stability and responsiveness of the suspension mass and optimize the design of the suspension mass. The moment of inertia is an indispensable parameter in vehicle dynamics simulation, suspension mass tuning and vehicle performance evaluation.

[0086] In actual operation, the calculation formula of the moment of inertia provided in the embodiment of the present application is determined based on writing the rotation differential equation for the spindle, and the derivation process is as follows: The rotation differential equation is as follows: ; The above equation is transformed to obtain the following formula: ; In the above formula, , then according to the differential equation theory is the vibration frequency, and the calculation formula for the moment of inertia can be obtained.

[0087] In summary, the embodiment of the present application first measures the load-bearing and deformation relationship of the leaf spring directly on the tractor by moving the front of the vehicle, thereby determining the stiffness of the leaf spring, avoiding errors caused by estimation, and ensuring the accuracy of the leaf spring stiffness data; in addition, the embodiment of the present application ensures the accuracy of the vibration frequency data by directly measuring the vibration frequency of the suspended mass when it is pitching around the axis of the balanced suspension spindle on the tractor; in addition, after obtaining the leaf spring stiffness and vibration frequency, the embodiment of the present application can calculate the moment of inertia of the suspended mass of the tractor around the axis of the balanced suspension spindle according to the leaf spring stiffness and vibration frequency. Due to the accuracy of the first two steps of measurement, the moment of inertia finally calculated also has a high accuracy.

[0088] It should be emphasized that since the embodiment of the present application directly measures the leaf spring stiffness and the vibration frequency of the suspended mass, the errors caused by the estimation method in the prior art are avoided, and thus the measurement accuracy of the moment of inertia can be significantly improved; in addition, since the measurement method provided in the embodiment of the present application is applicable to various types of tractors and is not limited by the specific structure or configuration of the vehicle, it has strong versatility and adaptability; in addition, the measurement tools and operating steps required in the embodiment of the present application are relatively simple and easy to implement in the laboratory or on-site, which reduces the measurement cost and time cost, and therefore has broad application prospects and practical value.

[0089] In a second aspect, the present application provides a rotational inertia measuring device for the suspension mass of a tractor, which is applied to a tractor, and a balancing suspension is provided on the tractor, and the suspension mass of the tractor can perform pitch vibration around the suspension spindle of the balancing suspension; Figure 5 As shown, Figure 5 A schematic diagram of the structure of a device for measuring the moment of inertia of the suspension mass of a tractor provided in an embodiment of the present application, the device comprising: a stiffness measuring module 210, a frequency measuring module 220 and an inertia measuring module 230; A stiffness determination module 210, for determining the leaf spring stiffness of the leaf spring on the tractor by moving the head of the tractor; The frequency determination module 220 is used to determine the vibration frequency of the suspended mass through the vibration of the front of the vehicle; wherein the vibration frequency of the suspended mass is the vibration degree of the suspended mass when it rotates around the axis of the balance suspension spindle; The inertia determination module 230 is used to determine the rotational inertia of the suspended mass of the tractor according to the leaf spring stiffness and the vibration frequency.

[0090] In one embodiment, the stiffness determination module 210 is further used to control the head of the tractor in a stationary state to be lifted from a current position to a preset height; The stiffness measuring module 210 is further used to control the head of the vehicle to move downward from a preset height at a preset speed and to measure the deformation of the leaf spring in the vertical direction and the bearing capacity of the leaf spring during the movement; The stiffness determination module 210 is also used to determine the leaf spring stiffness of the leaf spring according to the deformation amount and the load-bearing weight.

[0091] In one embodiment, the stiffness determination module 210 is further used to predict the suspension mass to obtain the predicted mass; The stiffness determination module 210 is further used to determine, according to the predicted mass, a current mass level to which the predicted mass belongs from a plurality of alternative mass levels; The stiffness determination module 210 is further used to determine the preset height of the suspended mass according to the corresponding relationship between the mass level and the preset height and the current mass level.

[0092] In one embodiment, the frequency determination module 220 is further used to control the front end of the tractor in a stationary state to vibrate so that the suspended mass vibrates within a preset amplitude and to determine the vibration data of the suspended mass during the vibration process; The frequency determination module 220 is further used to determine the vibration frequency of the suspended mass in the vertical direction according to the vibration data.

[0093] In one embodiment, the frequency determination module 220 is further used to predict the suspended mass to obtain the predicted mass; The frequency determination module 220 is further used to determine, according to the predicted quality, a current quality level to which the predicted quality belongs from a plurality of candidate quality levels; The frequency determination module 220 is further used to determine the preset amplitude of the suspended mass according to the corresponding relationship between the mass level and the preset amplitude and the current mass level.

[0094] In one embodiment, the inertia determination module 230 is further used to determine the moment of inertia of the suspended mass according to the leaf spring stiffness, the vibration frequency and the moment of inertia calculation formula; wherein the moment of inertia calculation formula is as follows:

[0095] In the formula, represents the suspended mass of the tractor; Indicates the distance between the longitudinal center point of the leaf spring and the axis center of the balancing suspension spindle; represents the leaf spring stiffness; represents the vibration frequency.

[0096] Third, the present application also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, steps S110 to S130 provided in the above embodiment are implemented.

[0097] Fourth, the present application also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, steps S110 to S130 of the above embodiment are executed.

[0098] Fifth, the computer program product provided in the present application includes a computer-readable storage medium storing program code. The instructions included in the program code can be used to execute the method in the previous method embodiment. The specific implementation can refer to steps S110~S130 of the method embodiment, which will not be repeated here.

[0099] In the embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed may be through some communication interfaces, and the indirect coupling or communication connection of the devices or units may be electrical, mechanical or other forms.

[0100] In addition, the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, and may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0101] Furthermore, the functional modules in the various embodiments of the present application may be integrated together to form an independent part, or each module may exist independently, or two or more modules may be integrated to form an independent part.

[0102] It should be noted that if the function is implemented in the form of a software function module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or part of the contribution to the prior art or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, and other media that can store program codes.

[0103] In this document, relational terms such as first and second, etc. are used merely to distinguish one entity or operation from another entity or operation, but do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0104] The above description is only an embodiment of the present application and is not intended to limit the protection scope of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for measuring the moment of inertia of the suspended mass of a tractor, characterized in that: Applied to a tractor, the tractor is provided with a balancing suspension, and the tractor suspension mass can perform pitch vibration around the suspension spindle of the balancing suspension; the method comprises: Determining the leaf spring stiffness of the leaf spring on the tractor by moving the head of the tractor; Determining the vibration frequency of the suspended mass by the vibration of the front of the vehicle; The vibration frequency of the suspended mass is the vibration degree of the suspended mass when it rotates around the axis of the balance suspension spindle; The moment of inertia of the suspended mass of the tractor vehicle is determined based on the leaf spring stiffness and the vibration frequency.

2. The method according to claim 1, characterized in that The method of determining the leaf spring stiffness of the leaf spring on the tractor by moving the head of the tractor comprises: Controlling the front of the tractor in a stationary state to lift it from a current position to a preset height; Controlling the vehicle head to move downward from the preset height at a preset speed and measuring the deformation amount of the leaf spring in the vertical direction and the bearing weight of the leaf spring during the movement; The leaf spring stiffness of the leaf spring is determined according to the deformation amount and the load-bearing weight.

3. The method according to claim 2, characterized in that Before determining the leaf spring stiffness of the leaf spring on the tractor by moving the head of the tractor, the method further comprises: Predicting the suspension mass to obtain a predicted mass; According to the predicted quality, determining a current quality level to which the predicted quality belongs among a plurality of alternative quality levels; The preset height of the suspended mass is determined according to the corresponding relationship between the mass level and the preset height and the current mass level.

4. The method according to claim 1, characterized in that: Determining the vibration frequency of the suspended mass by the vibration of the vehicle head includes: Controlling the front of the tractor in a stationary state to vibrate so that the suspended mass vibrates within a preset amplitude and measuring vibration data of the suspended mass during the vibration process; Based on the vibration data, a vibration frequency of the suspended mass in a vertical direction is determined.

5. The method according to claim 4, characterized in that Before determining the vibration frequency of the suspended mass by the vibration of the vehicle head, the method further includes: Predicting the suspension mass to obtain a predicted mass; According to the predicted quality, determining a current quality level to which the predicted quality belongs among a plurality of alternative quality levels; The preset amplitude of the suspended mass is determined according to the corresponding relationship between the mass gear and the preset amplitude and the current mass gear.

6. The method according to claim 1, characterized in that Determining the moment of inertia of the tractor suspension mass according to the leaf spring stiffness and the vibration frequency includes: The moment of inertia of the suspended mass is determined according to the leaf spring stiffness, the vibration frequency and the moment of inertia calculation formula; wherein the moment of inertia calculation formula is as follows: In the formula, represents the suspended mass of the tractor; Indicates the distance between the longitudinal center point of the leaf spring and the axis center of the balancing suspension spindle; represents the leaf spring stiffness; represents the vibration frequency.

7. A device for measuring the moment of inertia of a tractor suspension mass, characterized in that: Applied to a tractor, the tractor is provided with a balancing suspension, and the tractor suspension mass can perform pitch vibration around the suspension spindle of the balancing suspension; the device comprises: a stiffness measurement module, a frequency measurement module and an inertia measurement module; The stiffness determination module is used to determine the leaf spring stiffness of the leaf spring on the tractor by moving the head of the tractor; The frequency determination module is used to determine the vibration frequency of the suspended mass through the vibration of the vehicle head; wherein the vibration frequency of the suspended mass is the vibration degree of the suspended mass when it rotates around the axis of the balance suspension spindle; The inertia determination module is used to determine the rotational inertia of the suspended mass of the tractor according to the leaf spring stiffness and the vibration frequency.

8. An electronic device, characterized in that: The electronic device comprises a processor and a memory, wherein the memory is used to store an application program, and the processor runs or executes a software program stored in the memory so that the electronic device implements the method for measuring the moment of inertia of the suspension mass of a tractor according to any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store program codes executed by a processor, wherein the program codes are used to implement the method for measuring the moment of inertia of the suspended mass of a tractor vehicle according to any one of claims 1 to 6.

10. A computer program product, characterized in that The computer program product comprises computer instructions. When the computer instructions are run on an electronic device, the electronic device implements the method for measuring the moment of inertia of the suspended mass of a tractor vehicle according to any one of claims 1 to 6.

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