IoT-based adaptive oxygen supply and vibration monitoring system for fruit and vegetable preservation pads

Abstract

The present invention discloses an adaptive oxygen supply and vibration monitoring system for fruit and vegetable fresh-keeping gaskets based on the Internet of Things, which relates to the technical field of fruit and vegetable fresh-keeping gasket monitoring. The system is used to solve the problem of being unable to detect the respiration characteristics and counteraction characteristics of fruits and vegetables in multi-source environmental parameters and having weak perception of abnormal state trends. The system collects oxygen, carbon dioxide, temperature and humidity data in fruit and vegetable packaging, analyzes the respiration characteristics of fruits and vegetables based on oxygen concentration and temperature, analyzes the respiration counteraction characteristics of fruits and vegetables in combination with carbon dioxide concentration and humidity, sets a vibration detection signal or an alarm signal after comparing the two, monitors the overall center of gravity displacement of fruits and vegetables after detecting the vibration detection signal, obtains average acceleration through an accelerometer, calculates the fruit and vegetable vibration index, and then detects the water vapor content generated by the respiration of fruits and vegetables to judge whether the fresh-keeping gasket is abnormal. Whether to set an alarm signal is determined based on the judgment result, and performs alarm processing, thereby significantly improving the detection quality of fruit and vegetable fresh-keeping gaskets.

Description

Technical Field

[0001] This invention relates to the field of fruit and vegetable preservation pad monitoring technology, and more specifically, to an Internet of Things-based adaptive oxygen supply and vibration monitoring system for fruit and vegetable preservation pads. Background Technology

[0002] Fruits and vegetables retain a certain degree of respiratory and metabolic activity during post-harvest storage and transportation. They are easily degraded in quality and spoiled due to factors such as changes in temperature and humidity, unsuitable gas environment, and mechanical vibration and impact. This seriously affects the commercial value of fruits and vegetables and the economic benefits of the supply chain. Traditional fruit and vegetable preservation packaging relies on passive modified atmosphere film or static preservation materials, which cannot actively identify and dynamically intervene in the changes in the state of fruits and vegetables during storage and transportation.

[0003] Especially in long-distance transportation or multi-stage turnover scenarios, fruits and vegetables are easily affected by multiple stresses such as repeated vibration, oxygen imbalance and humidity accumulation. This paper proposes a fruit and vegetable preservation pad for use in current operating scenarios to monitor the state changes of fruits and vegetables during storage and transportation.

[0004] The existing technology has the following shortcomings:

[0005] Currently, a simple monitoring method for collecting gas concentration, temperature and humidity data inside fruit and vegetable packaging using a fruit and vegetable preservation pad cannot detect the respiration and resistance characteristics of fruits and vegetables in multi-source environmental parameters, and has a weak perception of abnormal state trends, resulting in increased transportation loss rate. Therefore, an adaptive oxygen supply and vibration monitoring system for fruit and vegetable preservation pads based on the Internet of Things is proposed.

[0006] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0007] To overcome the aforementioned deficiencies of the prior art, embodiments of the present invention provide an Internet of Things-based adaptive oxygen supply and vibration monitoring system for fruit and vegetable preservation pads. This system addresses the problems mentioned in the background art by employing a fusion strategy of multi-source environmental sensing technology, embedded data processing methods, and dynamic anomaly identification mechanisms.

[0008] To achieve the above objectives, the present invention provides the following technical solution: an adaptive oxygen supply and vibration monitoring system for fruit and vegetable preservation pads based on the Internet of Things, including a data acquisition module, a pad analysis module, a vibration monitoring module, and an alarm execution module;

[0009] The data acquisition module is used to collect oxygen concentration, carbon dioxide concentration, temperature data and humidity data inside the fruit and vegetable packaging and transmit them to the gasket analysis module. After receiving the moisture detection signal, it detects the water vapor content produced by the respiration of the fruit and vegetables and sends the detection results to the alarm execution module.

[0010] After receiving oxygen concentration and temperature data inside the fruit and vegetable packaging, the gasket analysis module analyzes the respiration characteristics of the fruit and vegetables in the packaging environment. It also analyzes the respiration resistance characteristics of the fruit and vegetables in the packaging environment by combining carbon dioxide concentration and humidity data. Based on the respiration characteristics of the fruit and vegetables, it selects to set a vibration detection signal to be transmitted to the vibration monitoring module or set an alarm signal to be transmitted to the alarm execution module.

[0011] After receiving the vibration detection signal, the vibration monitoring module uses a displacement sensor to monitor the overall center of gravity displacement of the fruits and vegetables inside the packaging. It sets a moisture detection signal and sends it to the data acquisition module. The accelerometer obtains the average acceleration of the fruits and vegetables inside the packaging. Combined with the overall center of gravity displacement of the fruits and vegetables, the vibration index of the fruits and vegetables is calculated and transmitted to the alarm execution module.

[0012] The alarm execution module receives the detection results of the water vapor content generated by the respiration of fruits and vegetables and the vibration index of fruits and vegetables to determine whether the fruit and vegetable preservation pad is in an abnormal state. Based on the judgment result, it selects whether to set an alarm signal. If an alarm signal is detected, alarm processing is executed.

[0013] In a preferred embodiment, after receiving the oxygen concentration and carbon dioxide concentration inside the fruit and vegetable packaging, the gasket analysis module takes the logarithm of the oxygen concentration as the oxygen concentration coefficient inside the fruit and vegetable packaging and takes the logarithm of the carbon dioxide concentration as the carbon dioxide concentration coefficient inside the fruit and vegetable packaging.

[0014] In a preferred embodiment, after receiving the temperature and humidity data inside the fruit and vegetable packaging, the gasket analysis module calls the maximum temperature and maximum humidity values ​​inside the fruit and vegetable packaging from the temperature and humidity database, and uses the ratio of the temperature data inside the fruit and vegetable packaging to the maximum temperature value as the temperature influence parameter, and the ratio of the humidity data inside the fruit and vegetable packaging to the maximum humidity value as the humidity influence parameter.

[0015] In a preferred embodiment, the gasket analysis module uses the product of the oxygen concentration coefficient and the temperature influence parameter inside the fruit and vegetable packaging as the fruit and vegetable respiration characteristics of the packaging environment; and uses the ratio of the carbon dioxide concentration coefficient and the humidity influence parameter inside the fruit and vegetable packaging as the fruit and vegetable respiration resistance characteristics of the packaging environment.

[0016] In a preferred embodiment, the gasket analysis module subtracts the fruit and vegetable respiration resistance characteristics of the packaging environment from the fruit and vegetable respiration characteristics, uses the difference result as the preservation balance order of the fruit and vegetable preservation gasket, and compares the preservation balance order of the fruit and vegetable preservation gasket with a preset preservation abnormality threshold.

[0017] If the preservation balance order of the fruit and vegetable preservation pad inside the fruit and vegetable packaging exceeds the preservation abnormality threshold, the preservation function of the fruit and vegetable preservation pad is judged to be normal, and a vibration detection signal is set; otherwise, the preservation function of the fruit and vegetable preservation pad is judged to be abnormal, and an alarm signal is set.

[0018] In a preferred embodiment, after receiving the vibration detection signal, the vibration monitoring module uses a displacement sensor to monitor the overall center of gravity displacement of the fruits and vegetables inside the fruit and vegetable packaging, and uses an accelerometer to obtain the average acceleration of the fruits and vegetables inside the fruit and vegetable packaging.

[0019] The overall center of gravity coordinates of fruits and vegetables in the initial monitoring state are collected by displacement sensors. When a vibration detection signal is received, the overall center of gravity coordinates of fruits and vegetables in the current state are obtained in real time. Based on the coordinate difference between the current state and the initial monitoring state, the overall center of gravity displacement of fruits and vegetables is calculated using the Euclidean distance formula.

[0020] Once the overall center of gravity displacement of the fruits and vegetables is obtained, a moisture detection signal is sent to the data acquisition module.

[0021] In a preferred embodiment, after receiving the moisture detection signal, the data acquisition module detects the water vapor content generated by the respiration of fruits and vegetables through a humidity sensor and sends the detection result to the alarm execution module.

[0022] By collecting the initial humidity value inside the fruit and vegetable packaging, after the system receives the moisture detection signal, the current humidity value is obtained through the humidity sensor. The difference between the current humidity value and the initial humidity value is calculated, and combined with the packaging volume and the saturated water vapor density at the current temperature, the water vapor content produced by the respiration of the fruit and vegetables is obtained.

[0023] The water vapor content produced by the respiration of fruits and vegetables is used as the detection result and sent to the alarm execution module.

[0024] In a preferred embodiment, the vibration monitoring module uses an accelerometer to collect instantaneous acceleration values ​​of fruits and vegetables in three-axis directions using three-axis dynamic data, and obtains the average acceleration of fruits and vegetables inside the packaging by averaging calculation.

[0025] The overall center of gravity displacement of fruits and vegetables and the average acceleration of fruits and vegetables inside the packaging are standardized and then substituted into the logistic regression formula to calculate the vibration index of fruits and vegetables.

[0026] The calculated vibration index of the fruits and vegetables is transmitted to the alarm execution module.

[0027] In a preferred embodiment, the alarm execution module receives the detection results of water vapor content generated by fruit and vegetable respiration and the vibration index of the fruit and vegetable, and performs standardization processing on the detection results of water vapor content generated by fruit and vegetable respiration and the vibration index of the fruit and vegetable.

[0028] By substituting the water vapor content from the respiration of standardized fruits and vegetables, along with the vibration index of the fruits and vegetables, into the hyperbolic tangent function, the abnormal state coefficient of the fruit and vegetable preservation pad is obtained. The specific formula is as follows:

[0029] ;

[0030] In the formula, The abnormal state coefficient of fruit and vegetable preservation pads. The results show the water vapor content produced by the respiration of fruits and vegetables after standardized treatment. The vibration index of standardized fruits and vegetables, , The results show the water vapor content from the respiration of standardized fruits and vegetables, as well as the influence weights corresponding to the vibration index of the fruits and vegetables.

[0031] In a preferred embodiment, the alarm execution module compares the abnormal state coefficient of the fruit and vegetable preservation pad with a preset abnormal threshold. If the abnormal state coefficient of the fruit and vegetable preservation pad is greater than or equal to the preset abnormal threshold, then an alarm signal is set.

[0032] If the abnormal state coefficient of the fruit and vegetable preservation pad is less than the preset abnormal threshold, then choose not to set an alarm signal.

[0033] The alarm execution module monitors alarm signals in real time, and executes alarm processing when an alarm signal is detected.

[0034] After the alarm signal set by the gasket analysis module is transmitted to the alarm execution module, the same alarm processing operation is performed.

[0035] The technical effects and advantages of this invention are as follows:

[0036] This invention collects data on oxygen concentration, carbon dioxide concentration, temperature, and humidity within fruit and vegetable packaging. It analyzes the respiration characteristics of the fruit and vegetables in the packaging environment based on the oxygen and temperature data, and analyzes the respiration resistance characteristics based on the carbon dioxide and humidity data. By comparing the respiration characteristics and resistance characteristics of the fruit and vegetable environment, it selects to set vibration detection signals or alarm signals. Upon detecting a vibration signal, it monitors the overall center of gravity displacement of the fruit and vegetables within the packaging, obtains the average acceleration of the fruit and vegetables using an accelerometer, and calculates the vibration index of the fruit and vegetables based on the overall center of gravity displacement. It also detects the water vapor content generated by the respiration of the fruit and vegetables and determines whether the fruit and vegetable preservation pad is in an abnormal state. Based on the determination result, it selects whether to set an alarm signal; if an alarm signal is detected, it executes alarm processing, thereby significantly improving the detection quality of the fruit and vegetable preservation pad. Attached Figure Description

[0037] Figure 1This is a flowchart illustrating the implementation of the Internet of Things-based adaptive oxygen supply and vibration monitoring system for fruit and vegetable preservation pads according to the present invention.

[0038] Figure 2 This is a module framework diagram of the adaptive oxygen supply and vibration monitoring system for fruit and vegetable preservation pads based on the Internet of Things of this invention. Detailed Implementation

[0039] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0040] This invention collects data on oxygen concentration, carbon dioxide concentration, temperature, and humidity within fruit and vegetable packaging. It analyzes the respiration characteristics of the fruit and vegetables in the packaging environment based on the oxygen and temperature data, and analyzes the respiration resistance characteristics based on the carbon dioxide and humidity data. By comparing the respiration characteristics and resistance characteristics of the fruit and vegetable environment, it selects to set vibration detection signals or alarm signals. Upon detecting a vibration signal, it monitors the overall center of gravity displacement of the fruit and vegetables within the packaging, obtains the average acceleration of the fruit and vegetables using an accelerometer, and calculates the vibration index of the fruit and vegetables based on the overall center of gravity displacement. It also detects the water vapor content generated by the respiration of the fruit and vegetables and determines whether the fruit and vegetable preservation pad is in an abnormal state. Based on the determination result, it selects whether to set an alarm signal. If an alarm signal is detected, alarm processing is executed, thereby significantly improving the detection quality of the fruit and vegetable preservation pad, realizing real-time perception and early warning response to abnormal states of fruits and vegetables during storage and transportation, ensuring the stability of fruit and vegetable quality and extending the shelf life.

[0041] Example 1: An IoT-based adaptive oxygen supply and vibration monitoring system for fruit and vegetable preservation pads. Please refer to [link / reference]. Figures 1 to 2 It includes a data acquisition module, a gasket analysis module, a vibration monitoring module, and an alarm execution module, and the modules are connected by electrical signals.

[0042] The functions of each module are as follows:

[0043] The data acquisition module is used to collect oxygen concentration, carbon dioxide concentration, temperature data and humidity data inside the fruit and vegetable packaging and transmit them to the gasket analysis module. After receiving the moisture detection signal, it detects the water vapor content produced by the respiration of the fruit and vegetables and sends the detection results to the alarm execution module.

[0044] After receiving oxygen concentration and temperature data inside the fruit and vegetable packaging, the gasket analysis module analyzes the respiration characteristics of the fruit and vegetables in the packaging environment. It also analyzes the respiration resistance characteristics of the fruit and vegetables in the packaging environment by combining carbon dioxide concentration and humidity data. Based on the respiration characteristics of the fruit and vegetables, it selects to set a vibration detection signal to be transmitted to the vibration monitoring module or set an alarm signal to be transmitted to the alarm execution module.

[0045] After receiving the vibration detection signal, the vibration monitoring module uses a displacement sensor to monitor the overall center of gravity displacement of the fruits and vegetables inside the packaging. It sets a moisture detection signal and sends it to the data acquisition module. The accelerometer obtains the average acceleration of the fruits and vegetables inside the packaging. Combined with the overall center of gravity displacement of the fruits and vegetables, the vibration index of the fruits and vegetables is calculated and transmitted to the alarm execution module.

[0046] The alarm execution module receives the detection results of the water vapor content generated by the respiration of fruits and vegetables and the vibration index of fruits and vegetables to determine whether the fruit and vegetable preservation pad is in an abnormal state. Based on the judgment result, it selects whether to set an alarm signal. If an alarm signal is detected, alarm processing is executed.

[0047] It should be noted that a displacement sensor is a device that measures the displacement or deformation of an object, used to measure the overall center of gravity displacement of fruits and vegetables inside the packaging. An accelerometer is a sensor that measures the acceleration of an object, used to detect the acceleration when the overall center of gravity of fruits and vegetables inside the packaging shifts.

[0048] The data acquisition module uses an oxygen analyzer to detect the oxygen concentration inside the fruit and vegetable packaging in real time, and a carbon dioxide sensor to detect the carbon dioxide concentration inside the packaging in real time. After transmitting the oxygen and carbon dioxide concentration detection results to the gasket analysis module, the module uses temperature and humidity sensors to monitor the temperature and humidity data inside the fruit and vegetable packaging in real time, and transmits the real-time temperature and humidity data inside the packaging to the gasket analysis module simultaneously.

[0049] It should be noted that an oxygen analyzer is a device that measures the oxygen concentration in a gas, and is used to measure the oxygen concentration inside fruit and vegetable packaging. A carbon dioxide sensor is a device that measures the carbon dioxide concentration in the air, and in this example, it is used to measure the carbon dioxide concentration inside fruit and vegetable packaging.

[0050] After receiving the oxygen and carbon dioxide concentrations inside the fruit and vegetable packaging, the gasket analysis module first performs dimensionless processing using logarithmic standardization, and takes the logarithm of the oxygen concentration as the oxygen concentration coefficient inside the fruit and vegetable packaging, and takes the logarithm of the carbon dioxide concentration as the carbon dioxide concentration coefficient inside the fruit and vegetable packaging.

[0051] The higher the oxygen concentration or temperature inside the fruit and vegetable packaging, the higher the respiration efficiency of the fruits and vegetables, and the worse the preservation effect inside the packaging. Conversely, the higher the carbon dioxide concentration or lower the humidity inside the fruit and vegetable packaging, the lower the respiration efficiency of the fruits and vegetables, and the better the preservation effect inside the packaging. Fruit and vegetable preservation pads inside the packaging can reduce the respiration of fruits and vegetables to achieve a preservation effect. The preservation function of the fruit and vegetable preservation pads can be judged by the oxygen concentration, carbon dioxide concentration, temperature, and humidity inside the fruit and vegetable packaging.

[0052] After receiving the real-time monitoring results of temperature and humidity data inside the fruit and vegetable packaging, the gasket analysis module calls the maximum temperature and maximum humidity values ​​inside the fruit and vegetable packaging from the temperature and humidity database. The ratio of the temperature data inside the fruit and vegetable packaging to the maximum temperature value is used as the temperature influence parameter, and the ratio of the humidity data inside the fruit and vegetable packaging to the maximum humidity value is used as the humidity influence parameter.

[0053] It should be noted that the temperature and humidity database is a database for storing, managing, and analyzing the temperature and humidity at various points in time inside the fruit and vegetable packaging. In this example, it is used to retrieve the maximum temperature and maximum humidity values ​​inside the fruit and vegetable packaging.

[0054] The gasket analysis module uses the product of the oxygen concentration coefficient and the temperature influence parameter inside the fruit and vegetable packaging as the fruit and vegetable respiration characteristics of the packaging environment; and uses the ratio of the carbon dioxide concentration coefficient and the humidity influence parameter inside the fruit and vegetable packaging as the fruit and vegetable respiration resistance characteristics of the packaging environment.

[0055] The higher the oxygen concentration coefficient or the greater the temperature influence parameter of the packaging environment, the greater the respiration characteristics of fruits and vegetables in the packaging environment, the higher the respiration efficiency of fruits and vegetables, the worse the preservation effect inside the fruit and vegetable packaging, and the worse the preservation effect of fruit and vegetable preservation pads. Conversely, the higher the carbon dioxide concentration coefficient or the smaller the humidity influence parameter of the packaging environment, the greater the respiration resistance characteristics of fruits and vegetables in the packaging environment, the lower the respiration efficiency of fruits and vegetables, the better the preservation effect inside the fruit and vegetable packaging, and the better the preservation effect of fruit and vegetable preservation pads.

[0056] The gasket analysis module subtracts the fruit and vegetable respiration resistance characteristics from the packaging environment's respiration characteristics, and uses the difference result as the preservation balance order of the fruit and vegetable preservation gasket. The preservation balance order of the fruit and vegetable preservation gasket is then compared with a preset preservation anomaly threshold. Based on the comparison result, a vibration detection signal or an alarm signal is selected. The specific judgment logic is as follows:

[0057] If the preservation balance order of the fruit and vegetable preservation pad inside the fruit and vegetable packaging exceeds the preservation abnormality threshold, the preservation function of the fruit and vegetable preservation pad is judged to be normal, and a vibration detection signal is set; otherwise, the preservation function of the fruit and vegetable preservation pad is judged to be abnormal, and an alarm signal is set.

[0058] If the gasket analysis module is set to a vibration detection signal, it will be transmitted to the vibration monitoring module; if the gasket analysis module is set to an alarm signal, it will be transmitted to the alarm execution module.

[0059] In the vibration monitoring module, after receiving the vibration detection signal, the displacement sensor is used to monitor the overall center of gravity displacement of the fruits and vegetables inside the packaging.

[0060] Specifically, the overall center of gravity displacement of fruits and vegetables inside the packaging is the change in the coordinates of the center of gravity in three-dimensional space caused by vibration or physical disturbance during transportation. The acquisition logic is to collect the overall center of gravity coordinates of the fruits and vegetables in the initial monitoring state through displacement sensors. When a vibration detection signal is received, the overall center of gravity coordinates of the fruits and vegetables in the current state are obtained in real time. Based on the coordinate difference between the current state and the initial monitoring state, the overall center of gravity displacement of the fruits and vegetables is calculated using the Euclidean distance formula.

[0061] The displacement sensor is deployed below the fruit and vegetable preservation pad to acquire the mass distribution and dynamic positional changes of the fruit and vegetable assembly in three-dimensional space within the packaging. The initial monitoring state is based on the spatial mass distribution of the fruits and vegetables in a stable, static state during transportation. The displacement sensor acquires the overall center of gravity coordinates under this initial monitoring state. The current state is determined after the system receives a vibration detection signal; the same displacement sensor then acquires the overall center of gravity coordinates under the current state. The difference between the coordinates of the current state and the initial monitoring state is calculated using the Euclidean distance formula as follows:

[0062] ;

[0063] In the formula, This refers to the overall displacement of the center of gravity of the fruits and vegetables. , , The coordinates of the global center of gravity in the current state. , , The coordinates of the overall center of gravity under the initial monitoring state.

[0064] It should be noted that the greater the overall center of gravity displacement of fruits and vegetables, the stronger the physical disturbance and the wider the displacement range during packaging, transportation or handling. This indicates higher instability of the fruits and vegetables within the packaging, greater risk of mutual collision, compression or damage, and thus a higher vibration index.

[0065] Once the overall center of gravity displacement of the fruits and vegetables is obtained, a moisture detection signal is sent to the data acquisition module.

[0066] After receiving the moisture detection signal, the data acquisition module detects the water vapor content produced by the respiration of fruits and vegetables through a humidity sensor and sends the detection result to the alarm execution module.

[0067] The water vapor content produced by fruit and vegetable respiration is the increase in relative humidity caused by the conversion of internal moisture into water vapor and its release into the packaging environment due to the respiration metabolism of fruits and vegetables. The higher the water vapor content produced by fruit and vegetable respiration, the higher the abnormal state coefficient of the fruit and vegetable preservation pad, and the more necessary it is to set an alarm signal. The acquisition logic is to collect the initial humidity value inside the fruit and vegetable packaging. After the system receives the moisture detection signal, it obtains the current humidity value through the humidity sensor. After calculating the difference between the current humidity value and the initial humidity value, and combining it with the packaging volume and the saturated water vapor density at the current temperature, the water vapor content produced by fruit and vegetable respiration is obtained.

[0068] Among them, the humidity sensor is a miniature capacitive or resistive humidity detection device used to monitor changes in water vapor concentration in the fruit and vegetable packaging environment. The sensor can convert changes in capacitance, resistance or frequency caused by water molecules adsorbed on the surface of the sensing film in the environment into corresponding humidity electrical signal output.

[0069] It should be noted that the calculation formula, which combines the difference between the current humidity value and the initial humidity value with the formula for calculating the packaging volume and the saturated water vapor density at the current temperature, is as follows:

[0070] ;

[0071] In the formula, The water vapor content produced by the respiration of fruits and vegetables. The result is the difference between the current humidity value and the initial humidity value. The effective volume of gas inside the packaging, i.e., the packaging volume. Let be the saturated water vapor density at temperature T.

[0072] The water vapor content produced by the respiration of fruits and vegetables is used as the detection result and sent to the alarm execution module.

[0073] The average acceleration of fruits and vegetables inside the packaging is the average rate of change of velocity of the fruits and vegetables caused by external disturbances or transportation vibrations under a preset number of samplings. The greater the average acceleration of the fruits and vegetables inside the packaging, the higher the intensity of vibration impact on the fruits and vegetables, the more violent the overall disturbance, and the greater the vibration index of the fruits and vegetables. The instantaneous acceleration values ​​of fruits and vegetables in the three-axis directions are collected by an accelerometer with three-axis dynamic data, and the average acceleration of the fruits and vegetables inside the packaging is obtained by averaging.

[0074] It should be noted that the preset number of sampling times was obtained by our researchers through multiple sets of fruit and vegetable packaging and transportation simulation experiments. After comparing and analyzing the movement trajectory and acceleration response trends of fruits and vegetables under different vibration frequencies and intensities, the results were combined with the system response time and sensor refresh rate.

[0075] In triaxial dynamic data acquisition, the three axes refer to the three spatial dimensions detected by the accelerometer. The average calculation formula is expressed as follows:

[0076] ;

[0077] In the formula, The average acceleration of the fruits and vegetables inside the packaging. , , Let be the acceleration values ​​in the X, Y, and Z axes at the i-th sampling time. This represents the total number of times the acceleration data was sampled. is the index, representing the i-th sample.

[0078] The overall center of gravity displacement of fruits and vegetables and the average acceleration of fruits and vegetables inside the packaging are standardized to keep them under the same dimension.

[0079] It should be noted that the standardization methods include, but are not limited to, standard linear transformation based on interval scaling, statistical Z-Score standardization, or normalization based on nonlinear mapping functions. The application methods of standardization will not be elaborated here.

[0080] The vibration index of fruits and vegetables is calculated by substituting the overall center of gravity displacement of the standardized fruits and vegetables and the average acceleration of the fruits and vegetables inside the packaging into the logistic regression formula. The specific formula is expressed as follows:

[0081] ;

[0082] In the formula, L is the result of logistic regression calculation, i.e., the vibration index of fruits and vegetables, e is the natural base, and y is the linear combination term of the logistic regression model. Specifically, y is set as follows:

[0083] ;

[0084] In the formula, For bias terms, This refers to the overall center of gravity displacement of the standardized fruits and vegetables. The average acceleration of fruits and vegetables inside the standardized fruit and vegetable packaging. as well as These are the regression coefficients for the overall center of gravity displacement of the standardized fruits and vegetables and the average acceleration of the fruits and vegetables inside the packaging.

[0085] It should be noted that the higher the vibration index of fruits and vegetables, the higher the intensity of mechanical vibration they experience during packaging, transportation, or storage, and the greater the abnormal state coefficient of the fruit and vegetable preservation pad.

[0086] The calculated vibration index of the fruits and vegetables is transmitted to the alarm execution module.

[0087] In the alarm execution module, the detection results of water vapor content generated by the respiration of fruits and vegetables and the vibration index of fruits and vegetables are received, and the detection results of water vapor content generated by the respiration of fruits and vegetables and the vibration index of fruits and vegetables are standardized.

[0088] By substituting the water vapor content from the respiration of standardized fruits and vegetables, along with the vibration index of the fruits and vegetables, into the hyperbolic tangent function, the abnormal state coefficient of the fruit and vegetable preservation pad is obtained. The specific formula is as follows:

[0089] ;

[0090] In the formula, The abnormal state coefficient of fruit and vegetable preservation pads. The results show the water vapor content produced by the respiration of fruits and vegetables after standardized treatment. The vibration index of standardized fruits and vegetables, , The results show the water vapor content from the respiration of standardized fruits and vegetables, as well as the influence weights corresponding to the vibration index of the fruits and vegetables. The function itself has nonlinear compression properties, which can enhance the discrimination sensitivity at the critical point. (Outer layer) accomplish Standardized processing.

[0091] The abnormal state coefficient of the fruit and vegetable preservation pad is compared with the preset abnormal threshold. If the abnormal state coefficient of the fruit and vegetable preservation pad is greater than or equal to the preset abnormal threshold, an alarm signal is set.

[0092] If the abnormal state coefficient of the fruit and vegetable preservation pad is less than the preset abnormal threshold, then choose not to set an alarm signal.

[0093] It should be noted that the preset abnormal threshold was set by the researchers based on the analysis results of historical fruit and vegetable transportation data and the combined fitting results of multiple sets of sensor response test data, which will not be elaborated here.

[0094] Furthermore, the alarm execution module monitors alarm signals in real time, and executes alarm processing when an alarm signal is detected.

[0095] Furthermore, after the alarm signal set by the gasket analysis module is transmitted to the alarm execution module, the same alarm processing operation is performed.

[0096] Specifically, alarm handling includes sending wireless anomaly notifications to the host computer terminal, triggering local indicator lights / buzzers to indicate packaging abnormalities, and intervening in the control of local fruit and vegetable preservation pads, etc., which will not be elaborated here.

[0097] Finally, it should be noted that in this paper, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0098] Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "including a…" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0099] In this document, the singular forms “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0100] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can be referred to each other.

[0101] The above description of the disclosed embodiments will enable those skilled in the art to make or use various modifications to these embodiments. It will be apparent to those skilled in the art that the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application.

[0102] Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An IoT-based adaptive oxygen supply and vibration monitoring system for fruit and vegetable preservation pads, characterized in that: It includes a data acquisition module, a gasket analysis module, a vibration monitoring module, and an alarm execution module; The data acquisition module is used to collect oxygen concentration, carbon dioxide concentration, temperature data and humidity data inside the fruit and vegetable packaging and transmit them to the gasket analysis module. After receiving the moisture detection signal, it detects the water vapor content produced by the respiration of the fruit and vegetables and sends the detection results to the alarm execution module. After receiving oxygen concentration and temperature data inside the fruit and vegetable packaging, the gasket analysis module analyzes the respiration characteristics of the fruit and vegetables in the packaging environment. It also analyzes the respiration resistance characteristics of the fruit and vegetables in the packaging environment by combining carbon dioxide concentration and humidity data. Based on the respiration characteristics of the fruit and vegetables, it selects to set a vibration detection signal to be transmitted to the vibration monitoring module or set an alarm signal to be transmitted to the alarm execution module. After receiving the vibration detection signal, the vibration monitoring module uses a displacement sensor to monitor the overall center of gravity displacement of the fruits and vegetables inside the packaging. It sets a moisture detection signal and sends it to the data acquisition module. The accelerometer obtains the average acceleration of the fruits and vegetables inside the packaging. Combined with the overall center of gravity displacement of the fruits and vegetables, the vibration index of the fruits and vegetables is calculated and transmitted to the alarm execution module. The vibration monitoring module uses an accelerometer to collect instantaneous acceleration values ​​of fruits and vegetables in three-axis directions using three-axis dynamic data, and obtains the average acceleration of fruits and vegetables inside the packaging by averaging calculation. The overall center of gravity displacement of fruits and vegetables and the average acceleration of fruits and vegetables inside the packaging are standardized and then substituted into the logistic regression formula to calculate the vibration index of fruits and vegetables. The calculated vibration index of the fruits and vegetables is transmitted to the alarm execution module. The alarm execution module receives the detection results of the water vapor content generated by the respiration of fruits and vegetables and the vibration index of fruits and vegetables to determine whether the fruit and vegetable preservation pad is in an abnormal state. Based on the judgment result, it selects whether to set an alarm signal. If an alarm signal is detected, alarm processing is executed. The alarm execution module receives the detection results of water vapor content generated by the respiration of fruits and vegetables and the vibration index of fruits and vegetables, and performs standardized processing on the detection results of water vapor content generated by the respiration of fruits and vegetables and the vibration index of fruits and vegetables. By substituting the water vapor content from the respiration of standardized fruits and vegetables, along with the vibration index of the fruits and vegetables, into the hyperbolic tangent function, the abnormal state coefficient of the fruit and vegetable preservation pad is obtained. The specific formula is as follows: ； In the formula, The abnormal state coefficient of fruit and vegetable preservation pads. The results show the water vapor content produced by the respiration of fruits and vegetables after standardized treatment. The vibration index of standardized fruits and vegetables, , The results show the water vapor content from the respiration of standardized fruits and vegetables, as well as the influence weights corresponding to the vibration index of the fruits and vegetables.

2. The adaptive oxygen supply and vibration monitoring system for fruit and vegetable preservation pads based on the Internet of Things as described in claim 1, characterized in that: After receiving the oxygen and carbon dioxide concentrations inside the fruit and vegetable packaging, the gasket analysis module takes the logarithm of the oxygen concentration as the oxygen concentration coefficient and the logarithm of the carbon dioxide concentration as the carbon dioxide concentration coefficient.

3. The adaptive oxygen supply and vibration monitoring system for fruit and vegetable preservation pads based on the Internet of Things as described in claim 1, characterized in that: After receiving the temperature and humidity data inside the fruit and vegetable packaging, the gasket analysis module calls the maximum temperature and maximum humidity values ​​inside the fruit and vegetable packaging from the temperature and humidity database. The ratio of the temperature data inside the fruit and vegetable packaging to the maximum temperature value is used as the temperature influence parameter, and the ratio of the humidity data inside the fruit and vegetable packaging to the maximum humidity value is used as the humidity influence parameter.

4. The adaptive oxygen supply and vibration monitoring system for fruit and vegetable preservation pads based on the Internet of Things as described in claim 3, characterized in that: The gasket analysis module uses the product of the oxygen concentration coefficient and the temperature influence parameter inside the fruit and vegetable packaging as the fruit and vegetable respiration characteristics of the packaging environment; and uses the ratio of the carbon dioxide concentration coefficient and the humidity influence parameter inside the fruit and vegetable packaging as the fruit and vegetable respiration resistance characteristics of the packaging environment.

5. The adaptive oxygen supply and vibration monitoring system for fruit and vegetable preservation pads based on the Internet of Things as described in claim 4, characterized in that: The gasket analysis module subtracts the fruit and vegetable respiration resistance characteristics of the packaging environment from the fruit and vegetable respiration characteristics, and uses the difference result as the preservation balance order of the fruit and vegetable preservation gasket. The preservation balance order of the fruit and vegetable preservation gasket is then compared with the preset preservation anomaly threshold. If the preservation balance order of the fruit and vegetable preservation pad inside the fruit and vegetable packaging exceeds the preservation abnormality threshold, the preservation function of the fruit and vegetable preservation pad is judged to be normal, and a vibration detection signal is set; otherwise, the preservation function of the fruit and vegetable preservation pad is judged to be abnormal, and an alarm signal is set.

6. The adaptive oxygen supply and vibration monitoring system for fruit and vegetable preservation pads based on the Internet of Things as described in claim 5, characterized in that: After receiving the vibration detection signal, the vibration monitoring module uses a displacement sensor to monitor the overall center of gravity displacement of the fruits and vegetables inside the packaging, and uses an accelerometer to obtain the average acceleration of the fruits and vegetables inside the packaging. The overall center of gravity coordinates of fruits and vegetables in the initial monitoring state are collected by displacement sensors. When a vibration detection signal is received, the overall center of gravity coordinates of fruits and vegetables in the current state are obtained in real time. Based on the coordinate difference between the current state and the initial monitoring state, the overall center of gravity displacement of fruits and vegetables is calculated using the Euclidean distance formula. Once the overall center of gravity displacement of the fruits and vegetables is obtained, a moisture detection signal is sent to the data acquisition module.

7. The adaptive oxygen supply and vibration monitoring system for fruit and vegetable preservation pads based on the Internet of Things as described in claim 1, characterized in that: After receiving the moisture detection signal, the data acquisition module detects the water vapor content produced by the respiration of fruits and vegetables through a humidity sensor and sends the detection result to the alarm execution module. By collecting the initial humidity value inside the fruit and vegetable packaging, after the system receives the moisture detection signal, the current humidity value is obtained through the humidity sensor. The difference between the current humidity value and the initial humidity value is calculated, and combined with the packaging volume and the saturated water vapor density at the current temperature, the water vapor content produced by the respiration of the fruit and vegetables is obtained. The water vapor content produced by the respiration of fruits and vegetables is used as the detection result and sent to the alarm execution module.

8. The adaptive oxygen supply and vibration monitoring system for fruit and vegetable preservation pads based on the Internet of Things as described in claim 1, characterized in that: The alarm execution module compares the abnormal state coefficient of the fruit and vegetable preservation pad with the preset abnormal threshold. If the abnormal state coefficient of the fruit and vegetable preservation pad is greater than or equal to the preset abnormal threshold, then an alarm signal is set. If the abnormal state coefficient of the fruit and vegetable preservation pad is less than the preset abnormal threshold, then choose not to set an alarm signal. The alarm execution module monitors alarm signals in real time, and executes alarm processing when an alarm signal is detected. After the alarm signal set by the gasket analysis module is transmitted to the alarm execution module, the same alarm processing operation is performed.

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