A method and system for metrological verification of a pig farm electronic weigher

Abstract

This invention discloses a metrological verification method and system for electronic weighing instruments in pig farms, relating to the field of electronic weighing instrument verification technology. The method includes the following steps: acquiring the weighing sensor output signal of the electronic weighing instrument under test corresponding to each calibration excitation signal; matching the response characteristics in each weighing sensor output signal with preset target response characteristics to determine the target excitation signal; calculating a sensitivity calibration coefficient based on the target excitation signal and the preset standard weight; and determining the metrological verification result based on the sensitivity calibration coefficient. Compared to traditional methods that require several hours and a large number of weights for each verification, this method uses only a small number of prototypes and weights to establish a benchmark model during the calibration stage. Subsequent mass production and use can completely eliminate the need for weights, with a single unit verification taking only tens of seconds, significantly improving efficiency and reducing costs.

Description

Technical Field

[0001] This invention relates to the technical field of electronic weighing instrument calibration, and in particular to a metrological calibration method and system for electronic weighing instruments used in pig farms. Background Technology

[0002] In pig farming and trade settlement, the weighing accuracy of electronic scales in pig farms is crucial. With the large-scale deployment of intelligent pig farming, periodic metrological verification of pig weighing scales is a core step in ensuring the reliability of pig growth data. The sensitivity calibration coefficient (or weighing range calibration coefficient) of the electronic scale in a pig farm determines the correctness of its output signal as the actual load on the pig changes. The accuracy of the quantitative value directly determines the weighing accuracy of the scale. Therefore, in the production process and on-site farming of electronic scales in pig farms, calibrating the sensitivity and verifying the metrological performance of each device is a key step in ensuring its qualification. However, the current common technical solutions for metrological verification of electronic scales in pig farms heavily rely on high-grade standard weights. By loading standard weights one by one onto the pig weighing platform and recording the sensor's output value, the system calculates the sensitivity calibration coefficient by comparing the output value with the standard weight and verifies whether its indication error is within the allowable range. This traditional solution has many inherent defects, which seriously restrict verification efficiency and cost control, including: (1) High asset and maintenance costs due to reliance on a large number of standard weights: High-grade standard weights are expensive and require regular inspection and traceability. Transportation and storage conditions are stringent. For large-scale pig weighbridges commonly used in pig farms, the total weight of the required weights can reach several tons. Moreover, pig farms are mostly located in remote areas, which significantly increases the fixed asset investment and daily maintenance costs of enterprises. (2) Cumbersome and inefficient calibration process: The process of manually handling, loading and unloading weights is time-consuming and labor-intensive. It is particularly inconvenient to operate in the humid and narrow environment of pig houses. A single full-range calibration often takes several hours, becoming a bottleneck process in the maintenance of pig farm equipment and the process of transferring pigs to pens. (3) Space and manpower consumption: The storage of a large number of weights requires a dedicated site. The farm has limited space, and the operation relies on professional metrology personnel, which is not conducive to the automated management of pig farms. (4) Risk of weight inaccuracy: Standard weights may change in quality during use due to wear, corrosion, or harsh environments such as manure and disinfectants in pig houses. If not detected in time, it will cause a systematic deviation in the calibration values ​​of the entire batch of weighing instruments, affecting the accuracy of pig weighing data. (5) Difficult to support online and real-time verification: Due to the physical limitations of weight loading, traditional methods are almost impossible to quickly re-verify the pigs on the weighing site without disassembling the weighing instrument. However, pigs are frequently moved to different pens and sold, and the weighing instrument needs to be calibrated in a timely manner to ensure fair transactions. Summary of the Invention

[0003] The purpose of this section is to outline some aspects of embodiments of the present invention and to briefly describe some preferred embodiments. Simplifications or omissions may be made in this section, as well as in the abstract and title of this application, to avoid obscuring the purpose of these documents; however, such simplifications or omissions should not be construed as limiting the scope of the invention.

[0004] In view of the problems existing in the prior art, the present invention is proposed.

[0005] To address the technical problems existing in the prior art, the present invention provides a metrological verification method for electronic scales in pig farms. The present invention provides the following technical solution: applying at least one calibration excitation signal to the internal force excitation mechanism of the electronic scale to be tested, and acquiring the weighing sensor output signal of the electronic scale to be tested corresponding to each calibration excitation signal; The response characteristics in the output signal of each weighing sensor are matched with preset target response characteristics to determine the target excitation signal; the preset target response characteristics are obtained by calibrating the electronic weighing instrument under test and / or equipment of the same model as the electronic weighing instrument under test according to a preset standard weight. The sensitivity calibration coefficient is calculated based on the target excitation signal and the preset standard weight; the metrological verification result is determined based on the sensitivity calibration coefficient.

[0006] As a preferred embodiment of the metrological verification method for an electronic scale in a pig farm according to the present invention, the calibration excitation signal includes an excitation intensity parameter; the step of applying at least one calibration excitation signal to the internal force excitation mechanism of the electronic scale under test and acquiring the weighing sensor output signal of the electronic scale under test corresponding to each calibration excitation signal includes: According to different excitation intensity parameters, calibration excitation signals are applied to the internal force excitation mechanism of the electronic scale under test, and the weighing sensor output signal of the electronic scale under test corresponding to each calibration excitation signal is obtained.

[0007] As a preferred embodiment of the metrological verification method for an electronic scale in a pig farm according to the present invention, the step of calculating the sensitivity calibration coefficient based on the target excitation signal and the preset standard weight includes: The sensitivity coefficient is determined based on the excitation intensity parameter corresponding to the target excitation signal, the preset standard weight, and the preset scaling factor; the sensitivity coefficient is then used as the sensitivity calibration coefficient.

[0008] As a preferred embodiment of the metrological verification method for an electronic weighing instrument in a pig farm according to the present invention, the step of matching the response characteristics in the output signal of each weighing sensor with preset target response characteristics to determine the target excitation signal includes: The response characteristics are extracted based on the steady-state output readings of the weighing sensor before and after the calibration excitation signal is applied. Calculate the difference between the response characteristics and the preset target response characteristics to determine the response deviation; If the response deviation meets the preset approximation cutoff condition, the calibration excitation signal applied at that time is taken as the target excitation signal; if it does not meet the approximation cutoff condition, the excitation intensity parameter of the calibration excitation signal is corrected according to the response deviation, and the corrected calibration excitation signal is applied to the internal force excitation mechanism again to obtain a new weighing sensor output signal and re-match.

[0009] In a preferred embodiment of the metrological verification method for an electronic scale in a pig farm according to the present invention, the process of determining the preset target response characteristics includes: A calibration excitation signal corresponding to the preset standard weight is applied to the internal force excitation mechanism of at least one electronic weighing instrument to be calibrated, and the output signal of the weighing sensor of each electronic weighing instrument to be calibrated is collected; the electronic weighing instrument to be calibrated includes the electronic weighing instrument to be tested and / or a device of the same model as the electronic weighing instrument to be tested; The preset target response characteristics are determined based on the response characteristics in the output signals of all the weighing sensors.

[0010] In a preferred embodiment of the metrological verification method for an electronic scale in a pig farm according to the present invention, the metrological verification result includes metrological performance test results, and the determination of the metrological verification result based on the sensitivity calibration coefficient includes: Based on the sensitivity calibration coefficient, a virtual weight excitation signal is generated to perform metrological performance testing on the electronic weighing instrument under test, and the metrological performance testing results are obtained. The metrological performance test of the electronic weighing instrument under test includes: The unloaded reference data sequence of the electronic weighing instrument under test when the internal force excitation mechanism is closed, and the dynamic weighing data sequence when the internal force excitation mechanism is open and the virtual weight excitation signal is applied are obtained respectively. The metrological performance test results of the electronic weighing instrument under inspection are calculated based on the dynamic weighing data sequence, the unloaded reference data sequence, and the preset logarithmic function.

[0011] As a preferred embodiment of the metrological verification method for an electronic weighing instrument in a pig farm according to the present invention, the dynamic weighing data sequence includes a continuously acquired weighing output value sequence, a target weighing curve, and a sensor feedback curve; the step of calculating the metrological performance test result of the electronic weighing instrument under test based on the dynamic weighing data sequence, the unloaded reference data sequence, and a preset logarithmic function includes: Calculate the hysteresis time difference between the target weighing curve and the sensor feedback curve; Using the hysteresis time difference as a correction amount, the target weighing curve is translated along the time axis to obtain an aligned weighing reference curve that is time-aligned with the sensor feedback curve. Under the same time coordinate, the theoretical weighing value on the aligned weighing reference curve is compared with the actual weighing value on the sensor feedback curve point by point, the difference of each sampling point is calculated and a dynamic deviation sequence is formed, and the maximum dynamic deviation is extracted from the dynamic deviation sequence. The metrological performance test result of the electronic scale under test is calculated based on the maximum dynamic deviation, the average reading of the unloaded reference data sequence, and the preset logarithmic function.

[0012] A calibration system for a metrological verification method for an electronic weighing instrument in a pig farm, as described above, comprises: an excitation and acquisition module for applying at least one calibration excitation signal to the internal force excitation mechanism of the electronic weighing instrument under test and acquiring the output signal of the weighing sensor corresponding to each calibration excitation signal; a response matching module for matching the response characteristics in each weighing sensor output signal with preset target response characteristics to determine a target excitation signal; the preset target response characteristics are obtained by calibrating the electronic weighing instrument under test and / or equipment of the same model as the electronic weighing instrument under test according to a preset standard weight; a coefficient calculation module for calculating a sensitivity calibration coefficient based on the target excitation signal and the preset standard weight; and a result generation module for determining the metrological verification result based on the sensitivity calibration coefficient.

[0013] The present invention also discloses a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps of the above-described method for the metrological verification of an electronic scale in a pig farm.

[0014] The present invention also discloses a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the above-described metrological verification method for an electronic scale in a pig farm.

[0015] The beneficial effects of this invention are as follows: This invention provides a method for sensitivity calibration and metrological performance testing of electronic weighing instruments in pig farms that does not rely on any external standard weights. By employing non-contact internal force excitation and sensor feedback closed-loop control, it avoids calibration errors caused by weight wear, corrosion in the pig farm environment, or inconsistent operation, ensuring the long-term stability and traceability of the sensitivity calibration coefficient. Compared to traditional methods that require several hours and a large number of weights for each calibration, this method uses only a small number of pig farm weighing instrument prototypes and weights to establish a benchmark model during the calibration phase. Subsequent mass production and use on the pig farm can be completely independent of weights, with a single unit calibration taking only tens of seconds, significantly improving efficiency and reducing costs. It is particularly suitable for rapid, rotating calibration and performance testing of multiple weighing devices in a pig farm environment. Attached Figure Description

[0016] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort. Wherein: Figure 1 This is a schematic diagram of the overall process of a metrological verification method for an electronic scale in a pig farm proposed in this invention. Figure 2 The present invention proposes a preferred software testing process for implementation. Figure 3 This is a time-series diagram showing the relationship between the target weighing curve and the sensor feedback curve in a preferred embodiment of the present invention. Figure 4 for Figure 3 A comparison of curves after correction using the lag time difference as a compensation amount; Figure 5 The preferred embodiment shows an independent control timing diagram assigned by the host computer software to each verification station in a multi-station synchronous acquisition system. Detailed Implementation

[0017] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0018] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the spirit of the invention. Therefore, the invention is not limited to the specific embodiments disclosed below.

[0019] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The phrase "in one embodiment" appearing in different places in this specification does not necessarily refer to the same embodiment, nor is it a single or selective embodiment that is mutually exclusive with other embodiments.

[0020] Example 1 Reference Figure 1 As an embodiment of the present invention, a metrological verification method and system for electronic scales in pig farms are provided. This method includes the following steps: Step 1: Apply at least one calibration excitation signal to the internal force excitation mechanism of the electronic weighing instrument under test (taking a pig farm electronic weighing instrument as an example), and obtain the weighing sensor output signal of the electronic weighing instrument under test corresponding to each calibration excitation signal; The internal force excitation mechanism is an actuator built into the electronic weighing instrument, capable of generating a controllable mechanical force under electrical signal drive. It applies an equivalent force (such as the force exerted by a pig trampling) to the weighing sensor under static conditions without external weight loading, causing the weighing sensor to produce a precisely quantifiable response output. In this embodiment, the internal force excitation mechanism can employ, but is not limited to, an electromagnetic force balance actuator, a piezoelectric ceramic actuator, or a voice coil force generator, to convert electrical signals into force or torque, applying an action to the elastic body of the weighing sensor to simulate the effect of weight loading. Applying at least one calibration excitation signal to the internal force excitation mechanism of the electronic weighing instrument under test can be achieved by a controller converting a preset excitation intensity parameter into an electrical signal of corresponding amplitude, which is then transmitted to the drive end of the internal force excitation mechanism to induce it to generate a mechanical excitation equivalent to a standard weight.

[0021] The electronic weighing instrument under test is a complete weighing device integrating a load cell, an internal force excitation mechanism, and a signal processing and output module. As the object of metrological verification, it can receive external control commands, drive the internal force excitation mechanism to generate mechanical excitation, and simultaneously output the measurement signal from the load cell. The electronic weighing instrument under test can be a finished product already assembled on the production line, with its hardware structure consistent with the equipment used for initial calibration, ensuring the universality of the calibration benchmark.

[0022] In this embodiment, the load cell output signal is an electrical signal response data that reflects the magnitude of the force load applied by the load cell after the calibration excitation signal is applied. Specifically, the load cell output signal corresponding to each calibration excitation signal can be the steady-state output value reached by the load cell before and after the application of the excitation signal. For example, a reference output value can be collected when the excitation signal is zero (no load), and then a response output value can be collected after applying a specific excitation signal and waiting for the output to stabilize. It can be understood that the change in the load cell output signal carries the equivalent weight information generated by the internal force excitation mechanism, thereby providing a basis for subsequently determining the actual equivalent weight corresponding to each calibration excitation signal. To obtain the load cell output signal of the electronic scale under test corresponding to each calibration excitation signal, the load cell output reading can be triggered once or multiple times after each calibration excitation signal is applied and a preset stabilization delay is reached. For example, the output signal can be acquired by delaying a fixed time window after applying the excitation signal and waiting for the sensor response to reach a steady state before collecting a single reading; or by continuously sampling during the duration of the excitation signal to form a time series of output readings in order to extract dynamic response characteristics. This is particularly important for simulating the force fluctuations caused by changes in the center of gravity when pigs stand and walk, so as to accurately capture the changes in the weighing sensor response caused by the action of the internal force excitation mechanism.

[0023] Step Two: Match the response characteristics in the output signal of each weighing sensor with the preset target response characteristics to determine the target excitation signal. The response characteristics in the weighing sensor output signal are key parameters extracted from the output signal that characterize the change in sensor response caused by the action of the internal force excitation mechanism. In an exemplary embodiment, this response characteristic can be obtained by subtracting the reference steady-state output reading before the application of the calibration excitation signal from the steady-state output reading after the application of the excitation signal, characterizing the net response amplitude of the weighing sensor produced by the excitation intensity. This response characteristic can be directly calculated from the output value of a single acquisition, or it can be extracted after statistical processing (such as taking the average or median) of a continuously acquired output signal sequence, thereby obtaining an accurate and stable response quantification result.

[0024] The preset target response characteristic is a standardized response characteristic reference value predetermined during the calibration stage before metrological verification. This reference value corresponds to a known preset standard weight. For example, a common slaughter weight of 120 kg for pigs can be selected as the preset standard weight. Its function is to provide a clear quantitative target for matching the calibration excitation signal, so as to determine whether the equivalent weight response generated by the current excitation signal has achieved the expected standard weight effect (such as the standard pig weight). In an exemplary embodiment, the preset target response characteristic can be a representative value calculated by applying an excitation signal equivalent to the preset standard weight to multiple electronic scales of the same model under calibration conditions, collecting and extracting the response characteristics of each device, and then combining these response characteristic data.

[0025] Step 3: The preset target response characteristics are obtained by calibrating the electronic weighing instrument under test and / or equipment of the same model as the electronic weighing instrument under test based on a preset standard weight. The preset standard weight is a known and accurate mass value (such as the typical weight of an adult fattening pig) selected during the calibration phase, serving as the basis for establishing the mapping relationship between internal excitation signal parameters and physical weight. For example, in a calibration laboratory, the standard output value of the weighing sensor corresponding to the preset standard weight can be determined on standard equipment using high-grade standard weights, and then this can be used as a bridge to establish a conversion model between the excitation intensity parameter and the equivalent standard weight.

[0026] Matching the response characteristics of each weighing sensor's output signal with preset target response characteristics can be achieved by calculating indices such as the difference or relative deviation between the extracted response characteristics and the preset target response characteristics, thus quantifying the degree of similarity between the two. In an exemplary embodiment, the matching process involves comparing the actually measured response characteristics (such as the output difference) with the preset target response characteristics to determine whether the current calibration excitation signal has successfully simulated an effect equivalent to a preset standard weight. It is understood that the higher the degree of matching between the response characteristics corresponding to the calibration excitation signal and the preset target response characteristics, the closer the intensity of the calibration excitation signal is to the ideal value. This allows for the accurate establishment of an equivalent correspondence between the excitation parameters and the standard weight without the need for any standard weights, facilitating the accurate calculation of subsequent metrological calibration parameters and significantly reducing verification costs.

[0027] There are several options for the specific implementation strategy of applying at least one calibration excitation signal. In one exemplary embodiment, a set of excitation intensity parameters can be preset and applied to the electronic scale under test all at once or in batches. All corresponding output signals are collected and then matched and screened. In another preferred exemplary embodiment, a single successive approximation strategy can be adopted: first, a calibration excitation signal is applied and its response characteristics are obtained. Based on the deviation between the response characteristics and the preset target response characteristics, a new excitation signal that is closer to the target is dynamically calculated and applied. This process is iterated until the deviation between the response characteristics and the preset target response characteristics meets the preset conditions. Compared with the batch application and screening method, this closed-loop iterative method can achieve more accurate determination of the target excitation signal with fewer excitation attempts, resulting in higher verification efficiency and accuracy. Furthermore, determining the target excitation signal means selecting the excitation signal from the applied calibration excitation signal sequence that has the highest matching degree between its response characteristics and the preset target response characteristics, or whose matching error is within the preset acceptable range. This signal is used as the optimal equivalent excitation parameter, thereby extracting the excitation signal that best represents the equivalent effect of the standard weight from multiple excitation attempts, ensuring the accuracy of calibration modeling.

[0028] Step 4: Calculate the sensitivity calibration coefficient based on the target excitation signal and the preset standard weight. The sensitivity calibration coefficient is a core metrological parameter characterizing the proportional relationship between the change in the output signal of the electronic weighing instrument's load cell and the actual change in weight. In this embodiment, the sensitivity calibration coefficient is calculated based on the determined excitation intensity parameter of the target excitation signal and the preset standard weight. It is used to correct the sensitivity error of the electronic weighing instrument caused by sensor characteristic deviations or long-term drift, ensuring that the weight reading of the electronic weighing instrument accurately reflects the true weight. For example, calculating the sensitivity calibration coefficient based on the target excitation signal and the preset standard weight can be achieved by using the known equivalent weight simulated by the target excitation signal (i.e., the preset standard weight) to deduce the output response rate of the load cell under unit weight, thereby obtaining the sensitivity calibration coefficient. In an exemplary embodiment, the coefficient can be directly calculated using a preset linear or nonlinear calculation formula based on the excitation intensity parameter corresponding to the target excitation signal, the preset standard weight, and the preset force-to-electricity conversion coefficient.

[0029] Step 5: Determine the metrological verification result based on the sensitivity calibration coefficient. The metrological verification result is generated based on the sensitivity calibration coefficient and is the final output used to determine whether the metrological performance of the electronic weighing instrument under test meets the specified requirements. In one exemplary embodiment, the calculated sensitivity calibration coefficient can be directly output as the metrological verification result, achieving parametric calibration of the electronic weighing instrument under test. Furthermore, before outputting the result, abnormal sensitivity calibration coefficients can be screened and marked according to preset anomaly judgment rules (such as coefficients exceeding a reasonable range). In addition, the final metrological verification result can be visualized through a human-computer interaction interface. In another exemplary embodiment, after calculating the sensitivity calibration coefficient, this coefficient can be used for deeper metrological performance verification. That is, the sensitivity calibration coefficient is used to generate a dynamic virtual weight excitation signal, driving the internal force excitation mechanism to simulate the actual weighing process, and collecting and analyzing dynamic response data. Finally, the sensitivity calibration coefficient and dynamic performance verification indicators are combined to form a comprehensive metrological verification result report.

[0030] This embodiment provides a metrological verification method for electronic weighing instruments. The method involves applying at least one calibration excitation signal to the internal force excitation mechanism of the electronic weighing instrument under test and acquiring the output signal of the weighing sensor corresponding to each calibration excitation signal. The response characteristics in each weighing sensor output signal are matched with preset target response characteristics to determine the target excitation signal. The preset target response characteristics are obtained by calibrating the electronic weighing instrument under test and / or equipment of the same model as the electronic weighing instrument under test according to a preset standard weight. A sensitivity calibration coefficient is calculated based on the target excitation signal and the preset standard weight. The metrological verification result is determined based on the sensitivity calibration coefficient, by applying an internal force under static, weightless conditions. The excitation mechanism applies a controllable electrical signal, inducing the weighing sensor to produce a response equivalent to the standard weight. The output signal is collected and the response features are extracted and matched with the preset target response features to establish a non-loaded equivalent mapping model between the excitation electrical signal and the physical weight. This allows for precise matching of the target excitation signal and calculation of the sensitivity calibration coefficient without any standard weights or external force sources, thus completing the calibration of the electronic weighing instrument's metrological parameters. This completely avoids the dependence of traditional metrological verification on a large number of standard weights. The verification process can be completed automatically and quickly at regular production or usage stations, effectively reducing the costs of weight procurement, maintenance, and manual operation, achieving the technical effects of reducing verification costs and improving verification efficiency.

[0031] In one embodiment, the calibration excitation signal includes an excitation intensity parameter; applying at least one calibration excitation signal to the internal force excitation mechanism of the electronic scale under test, and acquiring the weighing sensor output signal of the electronic scale under test corresponding to each calibration excitation signal, includes: According to different excitation intensity parameters, calibration excitation signals are applied to the internal force excitation mechanism of the electronic scale under test, and the weighing sensor output signal of the electronic scale under test corresponding to each calibration excitation signal is obtained.

[0032] The excitation intensity parameter is a controllable physical quantity used to adjust the magnitude of the equivalent gravity generated by the internal force excitation mechanism, serving as a fundamental parameter determining the excitation amplitude in the calibration excitation signal. For example, this excitation intensity parameter can be the current value, voltage value, pulse width modulation duty cycle applied to the electromagnetic force excitation coil, or the amplitude of the driving voltage applied to the piezoelectric actuator, etc.

[0033] By applying calibration excitation signals to the internal force excitation mechanism according to different excitation intensity parameters, the controller can sequentially generate and output electrical signals of different amplitudes to the internal force excitation mechanism based on a preset excitation intensity sequence. Furthermore, when the internal force excitation mechanism adopts an electromagnetic force balance structure, the excitation intensity parameters can be mapped to the magnitude of the current flowing through the force coil, thereby generating different electromagnetic torques and equivalent to different standard weight effects. This excitation method based on electrical signal values ​​has the advantages of high precision, no mechanical wear, and good repeatability.

[0034] This embodiment provides a metrological verification method for electronic scales. By applying calibration excitation signals to the internal force excitation mechanism of the electronic scale under test according to different excitation intensity parameters and obtaining the corresponding weighing sensor output signals, it can ensure that the excitation value of each verification is accurate, controllable, and highly consistent. This avoids the verification errors caused by wear, contamination, or differences in manual operation of standard weights in traditional methods. Furthermore, when the sensor characteristics of the electronic scale itself drift, there is no need to rely on physical weights for recalibration. Adaptive metrological calibration can be achieved simply by updating the target value of the excitation intensity parameter, thereby reducing costs and improving verification efficiency.

[0035] In one embodiment, the sensitivity calibration coefficient is calculated based on the target excitation signal and the preset standard weight, including: determining the sensitivity coefficient based on the excitation intensity parameter corresponding to the target excitation signal, the preset standard weight and the preset scaling factor; and using the calculated sensitivity coefficient directly as the sensitivity calibration coefficient.

[0036] The preset conversion factor is a proportional constant used to characterize the mapping relationship between the excitation intensity parameter and the equivalent standard weight. Its function is to accurately convert the electrical excitation amount into the corresponding mechanical weight value. The sensitivity coefficient is a calculation result obtained from the excitation intensity parameter, the preset standard weight, and the preset conversion factor through a preset operation relationship. It can reflect the rate of change of the sensor output corresponding to a unit weight change and can be used as a core indicator to measure the sensitivity characteristics of the weighing sensor for subsequent metrological performance qualification.

[0037] In specific calculations, the sensitivity coefficient is determined based on the excitation intensity parameter corresponding to the target excitation signal, the preset standard weight, and the preset conversion factor. This can be achieved by multiplying the excitation intensity parameter by the preset conversion factor and then dividing by the preset standard weight to obtain the sensor response coefficient per unit standard weight. In an exemplary embodiment, the sensitivity coefficient can be calculated using the formula (excitation intensity parameter × preset conversion factor) / preset standard weight, and the result characterizes the excitation response intensity of the electronic weighing instrument under test under a unit standard weight.

[0038] This embodiment provides a metrological verification method for electronic scales. By determining the sensitivity coefficient based on the excitation intensity parameter corresponding to the target excitation signal, a preset standard weight, and a preset conversion factor, and using this sensitivity coefficient as the sensitivity calibration coefficient, the method transforms the determination process of the sensitivity calibration coefficient from the cumbersome operation of relying on the physical loading of standard weights into numerical calculation based on electrical excitation parameters, known standard weight values, and fixed conversion factors. This can eliminate calibration deviations caused by individual factors such as differences in mechanical assembly and sensor characteristics between different electronic scales. Without the need for any physical weights or external standard force sources, it significantly reduces the system complexity and consumable costs of metrological verification, achieving the technical effects of reducing verification costs and improving metrological consistency.

[0039] In one embodiment, the response characteristics in the output signal of each weighing sensor are matched with preset target response characteristics to determine the target excitation signal, including: Based on the steady-state output readings of the weighing sensor before and after the calibration excitation signal, the response characteristics are extracted. Calculate the difference between the response characteristics and the preset target response characteristics to determine the response deviation; If the response deviation meets the preset approximation cutoff condition, the calibration excitation signal applied at that time is taken as the target excitation signal; if it does not meet the approximation cutoff condition, the excitation intensity parameter of the calibration excitation signal is corrected according to the response deviation, and the corrected calibration excitation signal is applied to the internal force excitation mechanism again to obtain a new weighing sensor output signal and re-match.

[0040] The steady-state output reading refers to the effective measured value of the weighing sensor output when it reaches a stable state after the excitation is applied. It can be obtained by continuously sampling the sensor output during the excitation period, and taking the average or median value when the fluctuation range of the sampled values ​​is less than a preset steady-state threshold. The response characteristic can be obtained by subtracting the steady-state output reading after the excitation from the reference steady-state output reading before the excitation, which represents the net response amplitude of the sensor produced by the excitation intensity.

[0041] Response deviation is the quantitative difference between the actual measured response characteristics and the preset target response characteristics, serving as feedback for the adaptive adjustment of the driving excitation signal throughout the closed-loop approximation process. In an exemplary embodiment, the response deviation can be directly calculated by algebraically subtracting the value of the response characteristic from the value of the preset target response characteristic. Exemplarily, the response deviation can be expressed as a positive deviation (actual response greater than the target response) or a negative deviation (actual response less than the target response).

[0042] The preset approximation cutoff condition is a set of rules used to determine whether the response deviation has reached the acceptable metrological accuracy requirement, thereby deciding whether to terminate the iterative approximation process. For example, the approximation cutoff condition may include, but is not limited to: an absolute deviation threshold condition (the absolute value of the response deviation is less than a preset maximum allowable deviation), a relative deviation change rate threshold condition (the change in response deviation between two adjacent iterations is less than a preset upper limit of change rate), and a maximum iteration count cutoff condition. The maximum iteration count cutoff condition, by setting the maximum number of times the excitation signal can be applied, can prevent infinite iteration due to abnormal conditions.

[0043] Determining whether the response deviation meets the preset approximation cutoff condition involves comparing the currently calculated response deviation with the corresponding threshold in the approximation cutoff condition. For example, if the absolute value of the response deviation is less than the preset absolute deviation threshold, it is determined to meet the condition; or if the rate of change of the response deviation between two consecutive iterations is less than the preset relative rate of change threshold, it is determined to meet the condition; or if the number of excitation iterations executed reaches the set maximum number of iterations, it is also forcibly determined to meet the condition. This achieves automatic termination control of the verification process, ensuring verification accuracy while avoiding redundant approximation operations.

[0044] The calibration excitation signal is used as the target excitation signal. Specifically, when the response deviation meets the approximation cutoff condition, the currently applied calibration excitation signal and its corresponding excitation intensity parameter are recorded as the final matching result, which is the target excitation signal.

[0045] A calibration excitation signal, corrected based on the response deviation, is applied to the internal force excitation mechanism. Specifically, this can be achieved by taking the value and sign of the response deviation as input, calculating a correction amount using a preset adjustment algorithm, and then algebraically adding this correction amount to the excitation intensity parameter of the current excitation signal to generate a new excitation intensity parameter. For example, a proportional control algorithm can be used to directly set the corrected excitation intensity parameter equal to the current excitation intensity parameter minus the product of the proportional coefficient and the response deviation; or a more complex PID control algorithm can be used to dynamically calculate the correction amount based on historical deviation sequences, thereby achieving rapid adaptive optimization of the excitation signal. This ensures that the actual response characteristics of the weighing sensor stably approximate the preset target response characteristics, improving calibration accuracy.

[0046] This embodiment provides a metrological verification method for electronic weighing instruments. It extracts response characteristics from the steady-state output readings of the weighing sensor before and after the calibration excitation signal, calculates the difference between these response characteristics and a preset target response characteristic to obtain the response deviation, and determines whether to complete matching or perform iterative correction based on whether the response deviation meets a preset approximation cutoff condition. Utilizing the high-precision measurement capability of the weighing sensor itself and the precise controllability of its internal force excitation mechanism, an adaptive closed-loop approximation process for the equivalent weight response is constructed. This allows for the accurate determination of the target excitation signal equivalent to a preset standard weight without any standard weights or external standard force sources, and the calculation of the sensitivity calibration coefficient accordingly. This significantly improves the accuracy and automation of metrological verification while reducing reliance on physical standards, giving the verification process high adaptability and robustness, achieving high-precision and high-efficiency metrological verification even without standard weights.

[0047] In one embodiment, the process of determining the preset target response characteristics includes: A calibration excitation signal corresponding to a preset standard weight is applied to the internal force excitation mechanism of at least one electronic weighing instrument to be calibrated, and the output signal of the weighing sensor of each electronic weighing instrument to be calibrated is collected; the electronic weighing instrument to be calibrated includes the electronic weighing instrument to be tested and / or a device of the same model as the electronic weighing instrument to be tested; Based on the response characteristics in the output signals of all weighing sensors, determine the preset target response characteristics.

[0048] The electronic scale to be calibrated is a device unit used to construct a preset target response characteristic. Its hardware structure, sensor model, and force excitation mechanism type are consistent with the electronic scale to be tested. It is used to establish a unified benchmark by collecting group response data during the calibration stage, providing a standardized reference for the subsequent metrological verification of individual electronic scales. In this embodiment, the electronic scale to be calibrated can be several qualified devices randomly selected from the same batch of production lines. These devices share the same sensor specifications, force excitation mechanism model, and control firmware as the electronic scale to be tested, and independently perform the calibration process at the calibration station.

[0049] The calibration excitation signal is an electrical excitation signal applied to the internal force excitation mechanism of the electronic scale to be calibrated during the calibration phase. This signal corresponds to a preset standard weight and is used to precisely induce the force excitation mechanism to produce a mechanical response equivalent to the standard weight, thereby establishing a mapping relationship between the electrical excitation amount and the standard weight value. In an exemplary embodiment, the calibration excitation signal can be calculated by the calibration control system based on the preset standard weight value and the known force-to-electric conversion coefficient of the force excitation mechanism, generating an electrical signal with corresponding excitation intensity parameters.

[0050] Apply calibration excitation signals corresponding to preset standard weights to the internal force excitation mechanisms of at least one electronic scale to be calibrated. This can be done by first installing the electronic scale to be calibrated at the calibration station and putting it into a stable working state, and then having the calibration control system send excitation intensity signals bound to preset standard weight values ​​to each electronic scale to be calibrated sequentially or in parallel, thereby driving its internal force excitation mechanism to produce an equivalent standard weight effect.

[0051] The output signal of the load cell of each electronic scale to be calibrated is acquired. The steady-state output value can be read and recorded before and after the calibration excitation signal is applied, once the load cell output reaches a steady state. For example, a multi-channel synchronous acquisition system can be used to simultaneously capture the output signals of all load cells of the electronic scale to be calibrated, or a polling acquisition method can be used to sequentially read the output signal of each device according to its device number, and a timestamp can be associated with each set of data to correspond to the excitation application time.

[0052] Determining a preset target response characteristic based on the response characteristics of all weighing sensor output signals can be achieved by statistically analyzing the response characteristics of all weighing instruments to be calibrated under the same calibration excitation signal. This involves eliminating outliers and calculating central tendency to generate a unified response characteristic reference value that is representative of the group. In one specific embodiment, the median or arithmetic mean of the response characteristics of each weighing instrument to be calibrated can be determined as the preset target response characteristic. This statistical method effectively smooths out individual response differences between devices of the same model caused by manufacturing tolerances, generating a more universally applicable standardized target response characteristic, thereby improving the general applicability and reliability of subsequent metrological verification results.

[0053] This embodiment provides a metrological verification method for electronic weighing instruments. By applying calibration excitation signals corresponding to preset standard weights to the internal force excitation mechanism of at least one electronic weighing instrument to be calibrated, and collecting the output signals of the weighing sensors of each electronic weighing instrument to be calibrated, and determining preset target response characteristics based on the response characteristics in the output signals of all weighing sensors, a standardized response reference benchmark with representativeness of a group of equipment of the same model can be generated. The establishment process of this benchmark completely eliminates the dependence on standard weights and can be completed under static conditions using only the force excitation mechanism and weighing sensors of the equipment itself. This significantly improves calibration efficiency and benchmark reliability, achieving the technical effects of reducing metrological verification costs and improving the consistency of verification results.

[0054] In one embodiment, the metrological verification result includes the metrological performance test result. The metrological verification result is determined based on the sensitivity calibration coefficient, including: Based on the sensitivity calibration coefficient, a virtual weight excitation signal is generated to perform metrological performance testing on the electronic weighing instrument under test, and the metrological performance testing results are obtained. The virtual weight excitation signal refers to an electrical excitation signal generated based on a sensitivity calibration coefficient to simulate real weight changes. It can drive an internal force excitation mechanism to produce a mechanical response equivalent to a real weight load without any standard weight being applied, thus verifying the weighing accuracy of the electronic scale under test. In this embodiment, the virtual weight excitation signal can be generated by calculating a preset weight change waveform template with the sensitivity calibration coefficient to produce a corresponding excitation intensity parameter sequence. This sequence is output to the internal force excitation mechanism via a controller, thus equivalently simulating the application and removal of a standard weight.

[0055] The metrological performance test results are a quantitative evaluation output of the weighing accuracy of the electronic weighing instrument under test under the action of a virtual weight excitation signal. They are used to measure the response accuracy and stability of the weighing sensor and internal force excitation mechanism of the electronic weighing instrument under test in a simulated actual weighing scenario, in order to determine whether its metrological performance meets legal or factory requirements. For example, the metrological performance test results may include weighing indication error indicators, repeatability indicators, and off-center load adaptability indicators.

[0056] In practical implementation, using virtual weight excitation signals to test the metrological performance of the electronic weighing instrument under test can be achieved by inputting the generated virtual weight excitation signal sequence into the drive controller of the internal force excitation mechanism. During the process of simulating weight changes, the output reading sequence of the weighing sensor is simultaneously acquired. By comparing this output reading sequence with the theoretical weight value corresponding to the virtual weight excitation signal, parameters such as indication error and repeatability are calculated. This allows for closed-loop automated verification of the electronic weighing instrument's metrological performance in a completely static, weightless calibration environment. Therefore, by generating virtual weight excitation signals based on sensitivity calibration coefficients to test the metrological performance of the electronic weighing instrument under test and obtaining the test results, and by directly simulating weight loading using the internal force excitation mechanism in a static environment, and quantitatively evaluating metrological performance by analyzing the actual response of the weighing sensor, the reliance on a large number of standard weights in traditional metrological verification can be completely eliminated. This effectively avoids calibration errors caused by weight wear, contamination, and human error, achieving seamless integration of sensitivity calibration and metrological performance testing within the same weightless system. This significantly reduces the material and time costs of metrological verification, achieving the technical effects of reducing verification costs and improving verification efficiency.

[0057] The metrological performance testing of the electronic weighing instruments under inspection includes: The unloaded reference data sequence of the electronic weighing instrument under test with the internal force excitation mechanism closed, and the dynamic weighing data sequence with the internal force excitation mechanism open and a virtual weight excitation signal applied are obtained respectively. The metrological performance test results of the electronic weighing instrument under inspection are calculated based on the dynamic weighing data sequence, the no-load reference data sequence, and the preset logarithmic function.

[0058] The no-load reference data sequence refers to the sequence of output readings continuously collected by the weighing sensor under the condition that the internal force excitation mechanism is completely closed and no virtual weight excitation signal is applied. This sequence reflects the output fluctuations of the electronic weighing instrument itself under static environment caused by a combination of factors such as background noise, zero drift, and environmental micro-disturbances, and serves as a benchmark for measuring the original stability of the electronic weighing instrument when it is not excited. For example, the no-load reference data sequence can be obtained by continuously reading the output values ​​of the weighing sensor at a fixed sampling rate and recording them to form a time series under the condition that the electronic weighing instrument under test is stably placed in the calibration position and the internal force excitation mechanism is disabled.

[0059] Dynamic weighing data sequence refers to the sequence of output readings continuously acquired by the weighing sensor under the condition that the internal force excitation mechanism is activated and a virtual weight excitation signal is applied. This sequence reflects the actual response trajectory of the electronic weighing instrument during the simulated dynamic weight change process, and is used to characterize the measurement accuracy and tracking performance of the electronic weighing instrument in the simulated weighing working mode. It is the core observation data for evaluating metrological performance. In an exemplary embodiment, the dynamic weighing data sequence can be obtained by activating the internal force excitation mechanism and feeding in the generated virtual weight excitation signal sequence, while maintaining the same environmental conditions as when the no-load reference data sequence is acquired, to synchronously acquire the continuous output values ​​of the weighing sensor.

[0060] The preset logarithmic function can be a mathematical model used to map the relative relationship between the fluctuation characteristics of the unloaded reference data sequence and the dynamic weighing data sequence into a quantitative value of metrological performance. For example, the ratio of the root mean square value of the unloaded reference data sequence to the root mean square value of the error of the dynamic weighing data sequence relative to the theoretical weight value can be used to perform a logarithmic operation to base 10, and then multiplied by a preset performance scoring scaling factor to calculate a metrological performance score in decibels.

[0061] Furthermore, the metrological performance test results can be calculated based on the dynamic weighing data sequence, the unloaded reference data sequence, and the preset logarithmic function. This can be achieved by first subtracting the dynamic weighing data sequence from its corresponding theoretical weight value point by point to calculate the root mean square value of the error sequence; then calculating the root mean square value of the unloaded reference data sequence; and finally substituting the ratio of the two into the preset logarithmic function for calculation, and outputting the final metrological performance score as the test result.

[0062] This embodiment provides a metrological verification method for electronic weighing instruments. By acquiring the no-load reference data sequence of the electronic weighing instrument under test when the internal force excitation mechanism is closed and the dynamic weighing data sequence when the internal force excitation mechanism is turned on and a virtual weight excitation signal is applied, the method compares the background output of the device itself in a static environment with the simulated weighing response output. Through function switching and mathematical modeling, the method achieves a quantitative evaluation of metrological performance. This method completely avoids the dependence of traditional metrological verification on standard weights and external loading devices, and completes the automated verification of the metrological performance of electronic weighing instruments without any physical standard instruments. This achieves the technical effect of reducing verification costs and improving verification efficiency.

[0063] In one embodiment, the dynamic weighing data sequence includes a continuously acquired sequence of weighing output values, a target weighing curve, and a sensor feedback curve; based on the dynamic weighing data sequence, the unloaded reference data sequence, and a preset logarithmic function, the metrological performance test results of the electronic weighing instrument under inspection are calculated, including: Calculate the time lag between the target weighing curve and the sensor feedback curve; Using the hysteresis time difference as a correction factor, the target weighing curve is shifted along the time axis to obtain an aligned weighing reference curve that is time-aligned with the sensor feedback curve. Under the same time coordinate, the theoretical weighing value on the aligned weighing reference curve is compared with the actual weighing value on the sensor feedback curve point by point. The difference between each sampling point is calculated and a dynamic deviation sequence is formed. The maximum dynamic deviation is extracted from the dynamic deviation sequence. The metrological performance test results of the electronic scale under test are calculated based on the maximum dynamic deviation, the average reading of the unloaded reference data sequence, and the preset logarithmic function.

[0064] The dynamic weighing data sequence is a multi-dimensional dataset, including continuously acquired weighing sensor output value sequences, target weighing curves, and sensor feedback curves, used to comprehensively reflect the dynamic response characteristics of the electronic scale during simulated weighing. In this embodiment, the target weighing curve refers to the curve of theoretical weight changing over time, calculated from the virtual weight excitation signal based on a sensitivity calibration coefficient. The sensor feedback curve refers to the actual weight reading curve output by the weighing sensor, reflecting the response history of the force excitation mechanism. The hysteresis is the relative delay between the target weighing curve and the sensor feedback curve on the time axis, used to measure the degree of system response lag between receiving the excitation signal and the sensor outputting a stable response.

[0065] The theoretical weighing value sequence corresponding to the target weighing curve is a sequence formed by the weight values ​​of the target weighing curve at discrete sampling times. Time shifting of the theoretical weighing value sequence with lag time difference means shifting the entire theoretical weighing value sequence forward or backward along the time axis by the time difference, thereby aligning the theoretical excitation signal with the actual sensor response in time.

[0066] The maximum dynamic deviation is the maximum absolute value of the difference between the theoretical weighing value sequence after time alignment and the actual weight value of the sensor output sequence at the same instant. It is used to measure the level of residual dynamic weighing error after deducting system response lag. This maximum dynamic deviation can be obtained as follows: using the lag difference as compensation, shift the target weighing curve in the time domain to obtain a weighing reference curve that is phase-aligned with the sensor feedback curve; subtract the instantaneous weighing values ​​of the weighing reference curve and the sensor feedback curve at each same time coordinate to obtain a dynamic deviation sequence; take the maximum absolute value in this dynamic deviation sequence as the maximum dynamic deviation.

[0067] The mean reading of the no-load reference data sequence refers to the arithmetic mean of all sampled values ​​in the no-load reference data sequence collected when the internal force excitation mechanism is closed.

[0068] Furthermore, based on the maximum dynamic deviation, the average reading of the unloaded reference data sequence, and the preset logarithmic function, the metrological performance test result is calculated. Specifically, the ratio of the average reading to the maximum dynamic deviation is first calculated, and then the ratio is used as the true value to perform logarithmic calculation using the preset logarithmic function. The result of the calculation is taken as the metrological performance test result of the electronic scale to be tested.

[0069] This embodiment provides a metrological verification method for electronic weighing instruments. By calculating the hysteresis time difference between the target weighing curve and the sensor feedback curve, and performing time correction on the theoretical weighing sequence to eliminate the influence of response hysteresis, the method comprehensively calculates the metrological performance of electronic weighing instruments in dynamic simulated weighing processes based on the maximum dynamic deviation between the corrected theoretical sequence and the actual sequence, combined with the mean value of the no-load reference reading and the preset logarithmic function. This method can accurately quantify the metrological performance of electronic weighing instruments in dynamic simulated weighing processes, effectively improving the dynamic evaluation accuracy and consistency of metrological verification results.

[0070] To more clearly illustrate the technical solution of this application, a detailed embodiment is also provided. The technical terms used in this embodiment include: Sensitivity calibration coefficient: This coefficient describes the proportionality between a unit standard weight and the change in the output signal of the weighing sensor. The unit can be mV / kg or counts / kg. It is used to inform the system that every 1kg change in load corresponds to a change in the sensor output, thereby accurately converting the electrical signal into a weight value.

[0071] Force excitation mechanism sensitivity: refers to the equivalent gravitational force generated by the internal force excitation mechanism corresponding to a unit excitation intensity parameter. For example, the unit can be N / mA or g / code, indicating how much equivalent force can be generated by each current value or digital code.

[0072] Excitation intensity parameter: A quantitative parameter used to represent the action of the internal force excitation mechanism. It can be the current value corresponding to the electromagnetic force coil, the digital value of the PWM duty cycle, or the drive voltage code value of the piezoelectric actuator, etc. It can be understood that the equivalent weight ≈ excitation intensity parameter × force excitation mechanism sensitivity.

[0073] The sensor response characteristic, also known as the target value of the preset target response characteristic, refers to the steady-state change of the output signal of the weighing sensor after being excited. In this scheme, it usually refers to the output difference before and after excitation, reflecting the weight effect simulated by the internal force excitation mechanism.

[0074] In one embodiment, a method for metrological verification of electronic weighing instruments that can eliminate dependence on standard weights and achieve greater efficiency, lower cost, and greater flexibility is provided. This method includes the following steps: I. Implementation of Calibration Test Without Weights (I) Calibration Stage (Taking 10 identical weighing instruments as an example) First, the mapping relationship between the excitation parameters and the standard weight is calibrated in the laboratory. Ten prototype weighing instruments of the same model as those used in the pig farm to be tested are selected. Standard weights are used to determine the actual output response value of the sensor of each prototype at a preset standard weight (e.g., 120 kg corresponding to 50% of the full scale of the pig). Then, different excitation intensity parameters are applied to each prototype through the internal force excitation mechanism, and the sensor output is collected. The excitation intensity parameter that makes the output change equal to the output response value at the aforementioned standard weight is found. The response characteristics corresponding to this parameter are recorded, and the median of the response characteristics of the 10 prototypes is taken as the preset target response characteristic. This preset standard weight can be flexibly set based on the weight range of the main pig herds being weighed in the pig farm. At the same time, the correspondence between this excitation intensity parameter and the standard weight is obtained to establish a conversion model.

[0075] The calibration stage is an offline laboratory stage where a set of unchanging reference values ​​are determined using a small number of standard weights and a prototype. Subsequent mass production testing will not require the use of standard weights again.

[0076] The process of obtaining the Target Response may include: (1) Standard weight loading: Place the prototype on a standard test bench and record the steady-state output of the sensor when it is unloaded and loaded with a preset standard weight. Calculate the output difference as the reference response corresponding to the standard weight.

[0077] (2) Excitation scan: The controller outputs a series of calibration excitation signals with different excitation intensity parameters to the internal force excitation mechanism, and records the steady-state output difference of the sensor under each excitation parameter to form an excitation-response data pair.

[0078] (3) Find the equivalent excitation: Find the excitation intensity parameter that is closest to the standard weight reference response from the excitation-response data pair, and record the sensor response characteristics (i.e. output difference) at this time.

[0079] (4) Group statistics: Repeat the above steps for 10 prototypes to obtain 10 response feature values, and take the median as the preset target response feature. This median effectively smooths out individual differences between devices of the same model.

[0080] In response feature extraction, multiple sampled values ​​can be averaged to reduce the impact of noise. The median or average of data from multiple prototypes can be taken, thereby statistically balancing factors such as individual fluctuations in the sensitivity of the force excitation mechanism, sensor zero-point drift, and assembly tolerances, to obtain a representative "excitation-response" benchmark.

[0081] (ii) During the calibration phase, the electronic weighing instrument under test is continuously adjusted by collecting the output signal of the weighing sensor to approximate the preset target response characteristics, thereby obtaining the target excitation signal; then, the sensitivity calibration coefficient of the weighing instrument under test is derived: Sensitivity calibration coefficient = (target excitation signal intensity parameter × force-to-electricity conversion constant) / preset standard weight. (It is understood that the calculation formula can be adjusted according to the characteristics of different force excitation mechanisms).

[0082] The calibration phase involves actual production or on-site verification, requiring the acquisition of sensitivity calibration coefficients for each weighing instrument under test. Based on the Target Response obtained during the calibration phase, the target excitation signal for each weighing instrument can be identified, and the sensitivity calibration coefficients can then be calculated using a formula.

[0083] The target excitation signal can be obtained by using a "binary / successive approximation" method, and the specific steps include: (1) For each weighing instrument to be tested, the benchmark target response obtained during the calibration phase is used as the target.

[0084] (2) Adjust the excitation intensity parameters to make the sensor output response characteristics approximate the Target Response.

[0085] (3) Record the excitation intensity parameters at this time for calculating the sensitivity calibration coefficient.

[0086] Exemplarily, a calibration excitation signal with an excitation intensity parameter of C1 can be applied first according to a preset initial value, and the sensor output can be collected to obtain the actual response characteristic R1.

[0087] If R1 < Target Response, it means that the excitation intensity is too small, and the excitation intensity parameter needs to be increased in the next calibration excitation signal; if R1 > Target Response, it means that the excitation intensity is too large, and the excitation intensity parameter needs to be decreased in the next calibration excitation signal. Through several repetitions of binary or successive approximation until |R - Target Response| ≤ the preset error tolerance value (e.g., 0.01% of the full scale), that is, the convergence condition is reached. The excitation intensity parameter at this time is the calibrated target excitation signal, which makes the sensor output response characteristic the same as the preset target response characteristic, equivalent to applying the preset standard weight.

[0088] II. Implementation of the no-weight metering performance test (used to test the dynamic metering performance of the weighing instrument after applying the sensitivity calibration coefficient obtained in the above stage) (1) Hardware connection: Use an MCU as a virtual weight signal generator, communicate with another MCU running the metering control algorithm through the SPI bus. The latter converts the virtual weight signal into a target excitation signal according to the sensitivity calibration coefficient, and controls the internal force excitation mechanism (such as an electromagnetic force generator) to generate a dynamic force through a drive circuit. The output signal of the weighing sensor is amplified and converted by an analog-to-digital converter, and then collected by a high-speed data acquisition card (or 10 Gigabit tooling) and uploaded to the host PC. The names and execution contents of each component are shown in Table 1.

[0089] Table 1 Hardware structure

[0090] Among them, the excitation intensity parameter calculated by MCU-B is the actual target control amount for driving the internal force excitation mechanism. In an exemplary embodiment, the fixed conversion coefficient can be set accordingly according to the type of the force excitation mechanism. The force sensor feedback value (if any) is the actual force monitoring signal built into the force excitation mechanism or the sensor, used for closed-loop verification.

[0091] The lag time difference refers to the time delay between the virtual weight signal (target weighing curve) and the actual response curve of the sensor (sensor feedback curve), caused by mechanical response lag and signal transmission delay. The sensor feedback curve is a sequence of continuous weighing output values obtained through a high-speed data acquisition tooling, and its ideal shape should match the target weighing curve. The dynamic response error = the absolute value of the difference between the corrected theoretical weight value and the actual weighing value at the same moment, and the unit can be kg or g. The suppression ratio SR (or metering performance score) = 20×log 10(Root mean square value of no-load reference fluctuation / Root mean square value of dynamic response error) is used to quantify the ability of a weighing instrument to suppress internal excitation dynamic disturbances.

[0092] (II) Software Testing Process like Figure 2 As shown, the software testing process includes: (1) Loading the sensitivity calibration coefficient obtained from the previous calibration, setting the amplitude and frequency of the simulated weight change of MCU-A, and generating a virtual weight excitation signal. (2) Sending the virtual weight signal to MCU-B, and the MCU-B metrological algorithm converts it into a driving signal for the internal force excitation mechanism, driving it to generate dynamic force. (3) The high-speed data acquisition fixture continuously reads the output value of the weighing sensor and synchronously records the target weighing curve (theoretical value) and the sensor feedback curve (actual value), with a sampling frequency of 1000Hz, used to calculate the hysteresis. (4) The host computer analyzes the acquired data sequence: first, it calculates the cross-correlation function between the target weighing curve and the sensor feedback curve to obtain the hysteresis. Furthermore, in order to accurately evaluate the dynamic metrological performance of the electronic scale under test, it is necessary to accurately calculate its system response hysteresis. Figure 3 The diagram illustrates the temporal relationship between the target weighing curve and the sensor feedback curve during a dynamic simulated weighing process. The solid waveform represents the target weighing curve generated by the virtual weight excitation signal, reflecting the real-time change of the theoretical simulated weight; the dashed waveform represents the sensor feedback curve actually output by the weighing sensor. It is clearly visible that due to the electromechanical conversion delay of the internal force excitation mechanism, the sensor response time, and the signal transmission process, the sensor feedback curve lags behind the target weighing curve on the time axis. The time offset between the two waveforms at characteristic points such as peaks or zero crossings is defined as the hysteresis. Accurate calculation of this hysteresis is a prerequisite for subsequent time axis alignment and precise error analysis.

[0093] (5) Correct the time axis of the target weighing curve using the lag time difference to align it with the phase of the sensor feedback curve; calculate the difference between the corrected theoretical value and the actual value at each sampling point, and take the largest absolute value as the maximum dynamic deviation. When calculating key metrological performance indicators, the influence of the lag time difference must be eliminated. For example... Figure 4 As shown, to... Figure 3 The graph shows a comparison of the curves after correction using the lag time difference as a compensation factor. After time shifting, the originally lagging sensor feedback curve (actual weighing curve) and the target weighing curve (theoretical weighing curve) are phase aligned in the time domain. Under the same aligned time coordinate, Figure 4The magnified local area clearly shows the instantaneous difference between the theoretical and actual weighing values. This scheme calculates the difference at each sampling point in the entire dynamic sequence to form an error sequence, and extracts the point with the largest absolute difference from this sequence as the maximum dynamic deviation. This deviation value represents the maximum residual indication error of the electronic scale under test during dynamic weighing after deducting the inherent time delay of the system, and is the core quantitative indicator for measuring its dynamic measurement accuracy.

[0094] (6) Calculate the metrological performance score SR: SR = 20 × log 10 (Root mean square value of no-load reference data sequence / maximum dynamic deviation). Among them, the root mean square value of the no-load reference data sequence is the standard deviation of the weighing sensor output within the same sampling time when the internal force excitation mechanism is closed, which represents the background noise.

[0095] Understandably, in traditional weight-based testing, the measurement of no-load reference data and dynamic errors relies on the actual loading of weights; however, in this solution, these data are obtained entirely through static internal excitation and sensor output analysis.

[0096] Specifically, the steps for obtaining the no-load reference data sequence include: (1) keeping the internal force excitation mechanism closed and the weighing instrument under test in a stable no-load state. (2) continuously collecting the output value of the weighing sensor for 10 seconds at a sampling frequency of 1000Hz and calculating its root mean square value (RMS) as the background noise level. (3) saving the RMS value for use in the calculation of metrological performance score.

[0097] During dynamic testing, the maximum dynamic deviation is calculated as follows: (1) Extract the target weighing curve and the sensor feedback curve from the collected data, and calculate the lag time difference φ between them using a cross-correlation algorithm. (2) Shift the target weighing curve along the time axis by φ to align it with the phase of the sensor feedback curve. (3) After time-domain alignment, calculate the difference between the theoretical value and the actual value point by point, take the absolute value, and obtain the error sequence. Find the maximum value in the sequence as the maximum dynamic deviation. (4) Substitute the no-load reference RMS and the maximum dynamic deviation into the SR formula to obtain the metrological performance score. If SR is greater than the preset threshold (e.g., 20dB), the metrological performance is deemed qualified. It is understandable that if the verification result is unqualified, sensitivity calibration can be performed again or the equipment can be checked for abnormalities.

[0098] III. Design of Multi-Station Parallel Verification Scheme To address the potential interference issues that may arise when multiple electronic scales are simultaneously tested on a production line, this solution also provides an anti-crosstalk design that supports parallel testing at multiple stations. For example... Figure 5 As shown, it illustrates the independent control timing allocated by the host computer software to each calibration station in a multi-station synchronous acquisition system. Figure 5 The upper half of the diagram represents the timeline, while the lower half shows the excitation and acquisition timing of four parallel workstations (workstations 1 to 4). The system employs a time-division excitation and synchronous acquisition strategy: at any given moment, a dynamic virtual weight excitation signal is applied to the electronic scale under test at only one workstation (e.g., workstation 1), while the other workstations remain in a static, unloaded monitoring state. However, the high-speed data acquisition system synchronously and continuously samples the weighing sensor outputs from all workstations. The host computer software, based on preset timing logic, extracts and analyzes data from the excited workstations only within a specific time period, thereby physically eliminating mechanical crosstalk that might be transmitted between different workstations through the test bench, ensuring the accuracy and reliability of multi-workstation parallel metrological verification.

[0099] Furthermore, each weighing instrument can be configured with a unique ID and excitation frequency band, and frequency division multiplexing can be used to perform dynamic excitation at different frequencies simultaneously. Then, the response of each channel can be separated by digital filtering to further improve parallel efficiency.

[0100] This embodiment provides an electronic weighing instrument metrological verification method that fundamentally eliminates the need for standard weights: it provides a sensitivity calibration and metrological performance verification method that does not rely on any external standard weights; it significantly reduces verification costs: by eliminating the need for purchasing, transporting, maintaining, and tracing standard weights, it directly saves a significant amount of asset and labor costs, while also reducing storage space; it greatly improves verification efficiency: by eliminating the tedious steps of manually handling weights, a single calibration process can be completed automatically within 1 minute, and multiple workstations can operate in parallel, significantly improving production cycle time; it enhances the flexibility and deployability of verification: no special weight loading device is required, it is compatible with existing production line workstations, and facilitates on-site online verification; it improves the reliability and consistency of the solution: by adopting non-contact internal force excitation and sensor feedback closed-loop control, it avoids verification errors caused by weight wear or inconsistent operation, ensuring the long-term stability and traceability of the sensitivity calibration coefficient. Compared to traditional methods that require several hours and a large number of weights for each calibration, this method uses only a small number of prototypes and weights to establish a benchmark model during the calibration stage. In subsequent mass production and use, it can completely eliminate the need for weights, and the calibration of a single unit only takes tens of seconds, which greatly improves efficiency and significantly reduces costs.

[0101] This embodiment also discloses a metrological verification system for an electronic weighing instrument. The system includes: an excitation and acquisition module, used to apply at least one calibration excitation signal to the internal force excitation mechanism of the electronic weighing instrument under test, and acquire the weighing sensor output signal of the electronic weighing instrument under test corresponding to each calibration excitation signal; a response matching module, used to match the response characteristics in each weighing sensor output signal with preset target response characteristics to determine a target excitation signal; the preset target response characteristics are obtained by calibrating the electronic weighing instrument under test and / or equipment of the same model as the electronic weighing instrument under test according to a preset standard weight; a coefficient calculation module, used to calculate a sensitivity calibration coefficient based on the target excitation signal and the preset standard weight; and a result generation module, used to determine the metrological verification result based on the sensitivity calibration coefficient.

[0102] This embodiment also provides a computer device applicable to a metrological verification method for an electronic scale in a pig farm, comprising: a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions to implement a metrological verification method for an electronic scale in a pig farm as proposed in the above embodiment.

[0103] The computer device can be a terminal, comprising a processor, memory, communication interface, display screen, and input devices connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The communication interface is used for wired or wireless communication with external terminals; wireless communication can be achieved through Wi-Fi, carrier networks, NFC (Near Field Communication), or other technologies. The display screen can be an LCD screen or an e-ink screen. The input devices can be a touch layer covering the display screen, buttons, a trackball, or a touchpad on the computer device's casing, or an external keyboard, touchpad, or mouse.

[0104] This embodiment also provides a storage medium storing a computer program. When executed by a processor, the program implements a metrological verification method for an electronic scale in a pig farm as described in the above embodiment. The storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read Only Memory (EPROM), Programmable Red-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk.

[0105] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A metrological verification method for an electronic weighing instrument in a pig farm, characterized in that, Includes the following steps: At least one calibration excitation signal is applied to the internal force excitation mechanism of the electronic weighing instrument under test, and the weighing sensor output signal of the electronic weighing instrument under test corresponding to each calibration excitation signal is acquired; The response characteristics in the output signal of each weighing sensor are matched with preset target response characteristics to determine the target excitation signal; the preset target response characteristics are obtained by calibrating the electronic weighing instrument under test and / or equipment of the same model as the electronic weighing instrument under test according to a preset standard weight. The sensitivity calibration coefficient is calculated based on the target excitation signal and the preset standard weight; the metrological verification result is determined based on the sensitivity calibration coefficient.

2. The metrological verification method for an electronic scale in a pig farm according to claim 1, characterized in that: The calibration excitation signal includes an excitation intensity parameter; applying at least one calibration excitation signal to the internal force excitation mechanism of the electronic weighing instrument under test, and acquiring the weighing sensor output signal of the electronic weighing instrument under test corresponding to each calibration excitation signal, includes: According to different excitation intensity parameters, calibration excitation signals are applied to the internal force excitation mechanism of the electronic scale under test, and the weighing sensor output signal of the electronic scale under test corresponding to each calibration excitation signal is obtained.

3. The metrological verification method for an electronic scale in a pig farm according to claim 2, characterized in that: The step of calculating the sensitivity calibration coefficient based on the target excitation signal and the preset standard weight includes: The sensitivity coefficient is determined based on the excitation intensity parameter corresponding to the target excitation signal, the preset standard weight, and the preset scaling factor; the sensitivity coefficient is then used as the sensitivity calibration coefficient.

4. The metrological verification method for an electronic scale in a pig farm according to claim 1, characterized in that: The step of matching the response characteristics in the output signal of each of the weighing sensors with preset target response characteristics to determine the target excitation signal includes: The response characteristics are extracted based on the steady-state output readings of the weighing sensor before and after the calibration excitation signal is applied. Calculate the difference between the response characteristics and the preset target response characteristics to determine the response deviation; If the response deviation meets the preset approximation cutoff condition, the calibration excitation signal applied at that time is taken as the target excitation signal; if it does not meet the approximation cutoff condition, the excitation intensity parameter of the calibration excitation signal is corrected according to the response deviation, and the corrected calibration excitation signal is applied to the internal force excitation mechanism again to obtain a new weighing sensor output signal and re-match.

5. The metrological verification method for an electronic weighing instrument in a pig farm according to claim 1, characterized in that: The process of determining the preset target response characteristics includes: A calibration excitation signal corresponding to the preset standard weight is applied to the internal force excitation mechanism of at least one electronic weighing instrument to be calibrated, and the output signal of the weighing sensor of each electronic weighing instrument to be calibrated is collected; the electronic weighing instrument to be calibrated includes the electronic weighing instrument to be tested and / or a device of the same model as the electronic weighing instrument to be tested; The preset target response characteristics are determined based on the response characteristics in the output signals of all the weighing sensors.

6. The metrological verification method for an electronic scale in a pig farm according to claim 1, characterized in that: The metrological verification result includes the metrological performance test result, and the determination of the metrological verification result based on the sensitivity calibration coefficient includes: Based on the sensitivity calibration coefficient, a virtual weight excitation signal is generated to perform metrological performance testing on the electronic weighing instrument under test, and the metrological performance testing results are obtained. The metrological performance test of the electronic weighing instrument under test includes: The unloaded reference data sequence of the electronic weighing instrument under test when the internal force excitation mechanism is closed, and the dynamic weighing data sequence when the internal force excitation mechanism is open and the virtual weight excitation signal is applied are obtained respectively. The metrological performance test results of the electronic weighing instrument under inspection are calculated based on the dynamic weighing data sequence, the unloaded reference data sequence, and the preset logarithmic function.

7. The metrological verification method for an electronic weighing instrument in a pig farm according to claim 6, characterized in that: The dynamic weighing data sequence includes a continuously acquired weighing output value sequence, a target weighing curve, and a sensor feedback curve; the step of calculating the metrological performance test result of the electronic scale under test based on the dynamic weighing data sequence, the unloaded reference data sequence, and a preset logarithmic function includes: Calculate the hysteresis time difference between the target weighing curve and the sensor feedback curve; Using the hysteresis time difference as a correction amount, the target weighing curve is translated along the time axis to obtain an aligned weighing reference curve that is time-aligned with the sensor feedback curve. Under the same time coordinate, the theoretical weighing value on the aligned weighing reference curve is compared with the actual weighing value on the sensor feedback curve point by point, the difference of each sampling point is calculated and a dynamic deviation sequence is formed, and the maximum dynamic deviation is extracted from the dynamic deviation sequence. The metrological performance test result of the electronic scale under test is calculated based on the maximum dynamic deviation, the average reading of the unloaded reference data sequence, and the preset logarithmic function.

8. The calibration system for a metrological calibration method of an electronic scale in a pig farm according to any one of claims 1-7, characterized in that: The system includes: an excitation and acquisition module, used to apply at least one calibration excitation signal to the internal force excitation mechanism of the electronic weighing instrument under test, and to acquire the weighing sensor output signal of the electronic weighing instrument under test corresponding to each calibration excitation signal; The response matching module is used to match the response characteristics in the output signal of each of the weighing sensors with preset target response characteristics to determine the target excitation signal; the preset target response characteristics are obtained by calibrating the electronic weighing instrument under test and / or equipment of the same model as the electronic weighing instrument under test according to a preset standard weight. The coefficient calculation module is used to calculate the sensitivity calibration coefficient based on the target excitation signal and the preset standard weight; The result generation module is used to determine the metrological verification result based on the sensitivity calibration coefficient.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that: When the processor executes the computer program, it implements the steps of the metrological verification method for an electronic scale in a pig farm as described in any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by the processor, it implements the steps of the metrological verification method for an electronic scale in a pig farm as described in any one of claims 1 to 7.

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