KR20040102660A - RFID-Employed Fisheries Product Freshness Monitoring and Cold Chain System Management - Google Patents

Abstract

PURPOSE: A system for monitoring freshness of marine products and managing a cold chain using an RFID(Radio Frequency ID) equipped with a time-temperature sensor is provided to keep the freshness in a remainder available period and efficiently distribute/transfer the marine products through time-temperature monitor/trace while the marine products passes whole supply chain. CONSTITUTION: An RFID tag(10) comprises a time-temperature measurement module(20), a transceiver(30), an antenna(40), a converter(50), a memory(60), and a temperature measurement module(70). The transceiver controls communication between an RFID reader and the tag. The converter converts a received analog signal into a digital signal or vice versa. The time measurement module calculates elapsed time. Used with the temperature measurement module, the time measurement module presents a proper reference for a possibility that the freshness of the marine products is changed by informing the elapsed time from a time point that the RFID tag is exposed to a specified temperature range.

Description

RFID-Employed Fisheries Product Freshness Monitoring and Cold Chain System Management}

Developed to compensate for the shortcomings and shortcomings of wired readers and barcodes, Radio Frequency Identification is a system that identifies tags attached to goods through radio signals from readers and transmits data to the host. Therefore, RFID is useful in the work environment where the work cannot be done only with the existing barcode.

RFID basically consists of a reader, a frequency, a tag, and the like. In addition to the wireless connection between the reader and the tag, the salient features of the RFID system include: (1) free data changes and addition of tags, (2) reading a large number of tags at a time, and (3) cold, humid, dust, and heat. The reading rate is high even in poor reading environment.

Depending on whether the output battery is attached to the tag, it is divided into active system and passive system. The passive system does not have its own output battery attached to the tag and receives output power from the reader. Therefore, it supports short-range reading within 2 ~ 3m and is relatively inexpensive. Active systems, on the other hand, have their own output battery attached to the tag, which is higher than passive systems and supports 3-10m long readings. In addition to the types mentioned above, there are also long range and positioning RFID systems with a wider reading range than these.

In Korea, 10 vendors are currently supplying RFID systems, but they are mainly used in bus cards, entrance security and attendance cards that are not directly related to commerce. Although it is not universal because it is weaker than conventional barcodes in terms of price and cost competitiveness, RFID systems are expected to be widely used in the distribution / logistics sector in the future. In particular, it is expected to guarantee fast and accurate readings from the time of goods shipment and acquisition, inventory management, recycling, and tracking of pallets.

RFID SYSTEM has the following advantages.

① No contact resistance: The physical contact of the reader is inevitable in the communication of contact type data carriers.

There is a problem such as deterioration of data quality. In the non-contact type, the stress does not occur because the data carrier and the reader are not in contact.

It has nothing to do with failure.

② Strong against external environment: In non-contact type, there is no interruption of communication even if nonmetallic body exists between data carrier and reader. Therefore, it can be used in the environment where moisture, oil, dust or dirt are present.

It is also possible to conceal or waterproof the reader. The connection is also

It is not exposed and is not affected by static electricity.

③ Short operation time: In the contact type data carrier system, contact must be made in order to communicate. Therefore, a certain sequence of operations is required. In the case of the non-contact type, even if a nonmetallic body exists between the data carrier and the reader, the communication time can be reduced because there is no interruption in communication.

④ Possibility of simultaneous access: data in contact or close data carrier system

The communication between the carrier and the reader is always one to one,

In mode mode, communication is possible at a long distance.

Multiple data carriers can be accessed at the same time.

The fishery industry is an important food industry that currently supplies about 45% of the animal protein consumed by Koreans, accounting for 2.4% of the world's production and ranks 10th in the world. With changes in the pattern of national vegetation and growing interest in health, aquatic products are now being used not only as a protein source but also as a dietary supplement. However, seafood is limited in terms of time and place to be produced, and it is easy to change the quantity of production as well as change. Therefore, appropriate storage means and rapid distribution processes are required for smooth supply and efficient use. According to a US FDA report, about 20% of foods in circulation in the supply chain are lost due to corruption or alteration. For this reason, for foods that are susceptible to corruption and deterioration, such as seafood, the efficient and rapid handling process improved by introducing into the supply chain is improved, preventing timely inevitable losses due to timely handling and monitoring. It is time to rationalize management.

Therefore, not only the acquisition of country of origin information but also the identification of products, information exchange system and automatic identification technology in the entire supply chain to meet the needs of consumers as the business and vitalization of business are increasing. It is necessary to introduce management systems already being promoted in other food industries, such as management systems and electronic document exchange systems.

We developed a system equipped with a time-temperature measurement function in a typical type of passive RFID, and maintain the freshness within the remaining effective shelf life through monitoring and tracking the exposure temperature-time during the distribution process of the entire supply chain. And it is an object of the present invention to provide a foundation that can be efficiently carried out distribution and transport of seafood.

Conventional RFID does not have the ability to measure elapsed time, especially elapsed time until it reaches a certain exposure temperature. Such functionality is highly desirable for applications in which deterioration / corruption can occur in a relatively short time, such as food products such as aquatic products, fruits and vegetables, vegetables, and vaccines. As the recent "Fish Traceability" project and "Fish Labeling Regulations", which are being implemented in OECD countries such as the EU and Japan, consumers have come to ask for detailed information on fishery products. Countries are also requiring the same laws to be applied to countries exporting fishery products to the EU for the benefit and health of consumers in the region. As a member of the OECD and the world's 10th largest fishery country, Korea has been able to obtain accurate and timely information at every distribution point in the supply chain chain in terms of national fisheries development, modernization of fishery distribution, equity among OECD countries, and increased exports of seafood. It was time to feel the need urgently. Considering the limitations and drawbacks of barcodes, this information can be seen to be advancing / purchased through a new RFID reader. Therefore, in the present invention, through the development of the HW / SW system equipped with an auxiliary device capable of measuring the elapsed time / exposure temperature in the existing RFID, the scientific information that can determine how long the seafood was exposed to the leading non-suitable temperature range It is important to contribute to the advancement / activation of the fisheries distribution sector by increasing the credibility of leading fisheries in the market and providing information on the relative age (age in the distribution network) in the cold chain distribution market. Is a challenge.

1 is a block diagram of an RFID tag equipped with a time measurement module.

Figure 2 RFID tag in communication with the RFID explorer.

3 is a block diagram of a time measurement module mounted on an RFID tag.

4 is a block diagram of an RFID tag equipped with a time-temperature measurement module.

5 is a block diagram of a temperature measuring module mounted on an RFID tag.

The RFID tag referred to in the present invention is composed of (1) transmitting / receiving device, (2) memory (3) antenna, (4) converter, (5) time measuring module and (6) temperature measuring module.

The time measurement module 5 performs a function of notifying the time elapsed since the last charging state when the RFID tag is read by the searcher. The temperature measuring module 6 informs the elapsed time from the start point of being placed in such an environment when the RFID tag is exposed to a predetermined specific situation (leading maintenance unsuitable temperature). This high value-added functionality greatly contributes to the role of extending the scope of application of the general RFID.

The simplest form of diagram maintenance monitoring is to make a decision on the diagram according to the length and length of the elapsed time by measuring the elapsed time from the initial state in which the diagram is good, which is addressed in (System Configuration 1). Techniques for monitoring elapsed time-exposure temperature consolidation freshness are discussed in detail in (System Configuration 2).

(System configuration)

Configuration 1: Elapsed time on the distribution network-see Figure 3

Configuration 1 is a type in which only the time measurement module is incorporated into the passive RFID, and a method of measuring the elapsed time therefrom based on the amount of charge of the capacitor at some point in the past. At this time, the time measurement module is configured in the form of a resistor incorporating a capacitor. The precharged capacitor generates a discharge over time, and the elapsed time until the RFID tag is read by the searcher can be inverted based on the discharge amount and the dissipation rate. The role of the resistor is to control the degree of discharge. If a resistor with a high resistance is adopted, the discharge is slowed, and if a low resistor is used, the discharge is faster. Therefore, the question of which resistance value to select depends on the characteristics of the area to be applied.

The elapsed time is calculated from the resistance value and the remaining capacity of the capacitor. The time measurement unit (time scale) is also determined by the characteristics of the application to be solved. The elapsed time can also be recorded by installing a register in the time measurement module. The unit of time measurement can be preset before use in seconds, hours, weeks, years, etc., depending on the application. The data recorded in the register is sent to the reader at the time the RFID tag is read, so that the information on the elapsed time from the immediately preceding charging point can be obtained.

Configuration 2: elapsed time-temperature monitoring over distribution networks

Configuration 2 is equipped with (1) time measuring device and (2) micro-sensor for exposure temperature measurement in passive RFID to test how long a fish product on cold chain network or shipping is exposed to temperature that is not suitable for freshness maintenance. This is how you can do it. The microsensor for exposure temperature measurement measures and records the elapsed time from the point of time when the measured temperature is out of the critical temperature for maintaining the freshness, and when the exposure temperature is within the proper range, the timer Stops working.

In the present invention, the measurement variable is limited to the exposure temperature, but the microsensor adopted is (1) measuring the electrical conductivity according to the chemical reaction, and (2) measuring the change in the electrical conductivity according to the rise / fall of the pressure. It can be designed to be.

More details on RFID tags that can provide information about elapsed time-exposure temperature will be described based on the drawings.

FIG. 1 is a block diagram of an RFID tag. The tag 10 includes a time measurement module 20, a transmitter / receiver 30, an antenna 40, a converter 50, and a memory 60. Some of these can be bundled together to form a single chip.

The transmitter / receiver 30 controls communication between the RFID searcher and the tag that occurs through the antenna 40. The memory 60 performs various functions such as data recovery, operating protocol, data storage, and the like, and is configured as ROM, RAM, or non-volatile memory. At this time, the ROM stores information about the security of the computer and the OS of the RFID and cooperates with the processor to mainly manage internal control and control such as data flow and power switching. RAM memory is concerned with the temporary storage of data during the discovery or response of RFID tags. Non-Volatile Memory is responsible for storing data about the RFID tag itself and for maintaining this data while the tag is in a sleep state. Play a role. In addition, the memory 60 may be configured to include a data buffer for temporarily storing the data at the time of modulation of the data occurring in the process of entering data from the RFID tag.

The converter 50 performs tasks related to the shape change of the signal, such as converting a received analog signal into a digital signal or converting a signal to be transmitted from a digital form into an analog form.

The time measuring device 20 calculates the elapsed time and is configured by attaching one or several resistors to the capacitor. At this time, the resistance plays a role of controlling the amount of discharge from the point of time when the capacitor is charged. The lower the resistance value is, the higher the discharge degree is. Therefore, the resistance can be selectively selected by the user according to the complexity and use of the RFID configuration. If the theoretical value and the amount of charge remaining in the capacitor are known, the elapsed time can be calculated automatically. The elapsed time can also be determined by attaching a register to the time measuring device 20 or the transmitter / receiver 30 and reading the scale of the register. At this time, whether one division corresponds to seconds, minutes, hours ... can be set before use. This data is sent to the searcher along with relevant data at the time the RFID tag is retrieved by the reader.

The arrows in Figure 1 are intended to show the interaction. That is, the antenna 40 sends a digital signal sent from the searcher to the converter 50 to perform a shape conversion of the data if necessary, otherwise the signal is sent directly to the transmitter / receiver 30. The memory 60 exchanges data with the converter 50 and the transmitter / receiver 30 and performs the above-mentioned tasks. At this time, the time measurement module 20 plays a role of sending the elapsed time to the searcher at the time when the RFID is searched through interaction with the transmitter / receiver 30.

2 shows the communication between the RFID tag 10 and the searcher 100. The searcher 100 includes a decoder 120, a transceiver 130, and an antenna 140. Antenna circuit 140 is an inductor 144 ( ), Capacitor 142 ( ) And resistance 146 ( In this case, the resistor 146 may be configured as a variable resistor. On the other hand, the RFID tag 10 has an inductor 14 ( ), Capacitor 12 ( You can also configure). Explorer 100 is connected to inductor 14 ( ) Generates an induced current to charge the capacitor 12 to power the RFID tag 10. Once activated, the RFID tag 10 sends data existing in the non-volatile memory to the searcher 100.

Figure 3 shows in more detail the time measurement module 20 in communication with the memory 60, which is a capacitor 21. , Resistance 22 ( ), An AD converter 24, a control circuit 26, and an N-bit register 28. When the reaction is started by the searcher 100, the control circuit 26 charges the capacitor 21. The voltage across the capacitor , And residual voltage In this case, these relations can be expressed as follows.

Where t is time and R is resistance 22 ( ) And C is the capacitor ( ) Means capacity. Conversely Knowing the value, the elapsed time t from the initial charging time can be calculated inversely. In other words,

Residual voltage Is converted to a digital value by the A / D converter 24 and stored in the N-bit register. This voltage value is then passed to the searcher 100 along with the others stored in the memory 60.

4 shows a temperature measuring device added to FIG. When used with the temperature measuring device 70, the time measuring module 20 has a slightly different function than mentioned above, which is as follows. In other words, it is not just tracking the elapsed time from the previous state of charge, but in this case, it indicates the elapsed time from the point of time when the RFID tag is exposed to a specific temperature range. It can serve as a good guideline for the possibility of a failure in the lead. These functions are particularly useful for aquatic products, as well as for applications in the fast-corrupting food and pharmaceutical sectors and other products that require expiration dates that can be directly affected by freshness as the environment changes. In the present invention, the temperature is limited to the above, but in view of the above-mentioned point, the observed variable may be humidity, pressure, and the like, and accordingly, an appropriate microsensor may be attached to perform its function.

The temperature measuring module mentioned in the present invention can be implemented in several forms. The first implementation method is (Configuration 1) mentioned above, and the second configuration method is more complicated than (Configuration 1).

(A) As an embodiment in which the time measuring module 20 serves as a kind of environmental measuring module (a broad meaning including temperature, humidity, and pressure), the rise / fall of the temperature and the rise / fall of the conductivity of the resistance are directly proportional to each other. I was focused on. In other words, it is possible to know that the elapsed time of exposure can be tracked by measuring a specific time zone having a high conductivity. At this time, it is necessary to pay attention to the time measurement module 20 performed the role of the temperature measurement module at the same time.

(B) As a second implementation method, a microsensor is introduced to detect a change from a predetermined environmental condition (for example, freshness threshold temperature). In other words, by attaching a microsensor to the time measurement module, the microsensor starts to operate from the moment when the temperature exceeds the threshold temperature, and the time measurement module connected to it keeps track of the elapsed time. .

Implementation B-1) It is a way to track the elapsed time from the register by operating the register when the microsensor starts to operate. When the RFID tag is read by the searcher, the total elapsed time can be calculated from the scale displayed by the register.

(Implementation B-2) The elapsed time can be extracted by disconnecting the circuit at the moment of reaching the critical temperature which is inappropriate for maintaining the lead.

(C) FIG. 5 shows a third implementation method in detail, which is intended to be developed in the present invention, in which the temperature measuring module 80 is merged with the time measuring module 90. The time measuring module 90 includes an A / D converter 94, a control circuit 96, and an N-bit register 98. The temperature measuring module 80 is connected to form a circuit through the contacts 84 and 86, and each contact is coupled with the resistors 92 and 93. In addition, the time measurement module 90 includes a capacitor 91 ( ) Is connected.

If the exposure temperature is lower than the set threshold temperature Q, the switch 82 is attached to the contact point 84 to connect the resistor 92 and the capacitor 91. Conversely, when the exposure temperature is higher than the threshold temperature, the switch 82 is connected to the contact 86 to connect the resistor 93 and the capacitor 91. That is, the switch 82 determines the degree of discharge of the capacitor 91 according to the ambient temperature.

Therefore, the initial voltage of the capacitor , Residual voltage In this case, the residual voltage after the time t has elapsed can be expressed as follows.

T : time

: Resistance value of resistance 92 )

: Resistance of resistor 93 ( )

C : Capacitor 91 ( Capacity

if >> , Elapsed time from when switch 82 makes contact with contact 86

It can be calculated as Therefore, it is possible to calculate the elapsed time from the time when the RFID tag 10 has exceeded the freshness holding threshold temperature.

The present invention not only monitors freshness and traces in the supply chain for foods such as fruits and vegetables, vegetables and vegetables, etc., but also tracks on the supply chain, as well as a number of products / pharmaceuticals (photo film, medicine, paint, Appropriately applicable to the battery, it is easy to make judgments about its freshness and / or its effectiveness. This will not only contribute to general public health improvement by enabling automatic monitoring of food lead maintenance, but also contribute to inventory management, warehouse management, and quick and accurate delivery / payment to the distribution / logistics industry such as courier service. It is also believed to have the effect of preventing unnecessary waste of manpower, time and resources.

In the present invention, attention is focused only on aquatic products and the temperatures to which they can be exposed during distribution. However, microsensors suitable for other environmental factors that may inadequately act on freshness, such as humidity, pressure, and harmful gases, may be used. You can take advantage of a package that combines a passive RFID with a very valid extension of its application.

Claims (15)

RFID Tags Memory for data storage -Transmitter / receiver associated with memory (memory <-> navigator) -Consists of a device capable of measuring the time elapsed from the initial condition. -Send information about elapsed time to explorer The time-measuring device attached to the RFID tag consists of a capacitor charged with a suitable capacity, and the elapsed time is calculated from the discharge amount of the capacitor. In addition to the charger, the RFID tag includes a resistor connected thereto, and the discharge amount of the charger is determined by the resistance value. The RFID tag measures elapsed time based on a preset time / second (seconds, minutes, hours ...) and includes a register for storing it. The RFID tag includes a temperature measuring device capable of detecting a change in temperature. The temperature measuring device attached to the RFID tag works like a time measuring device to determine the elapsed time from the initial set temperature (threshold temperature considered to be inadequate for maintaining the lead) to the time when the temperature value at the time of measurement is reached. The RFID tag includes a variable resistor whose resistance changes with temperature. The operation stage of the RFID tag is Measure elapsed time from initial situation It consists of the elapsed time transmission (reporting) step with the RFID explorer. Claim 8 subdivided again Sensing step of exposure to preset environment (inadequate threshold temperature) Measurement of the time range of exposure to a predetermined environment is made. The elapsed time measurement referred to in claim 8 includes the step of operating a timer when the freshness inadequate critical temperature value is exceeded. The measuring step mentioned in claim 10 includes the step of stopping the operation of the timer when the exposure temperature falls to a freshness maintaining range. Elapsed time measurement mentioned in claim 8 Charge of battery (initial state) Discharge of capacitor (at constant level) It consists of measuring the state of charge at the time of measurement, and elapsed time means the time elapsed until reaching the state of charge at the time of measurement. Judgment on the freshness, RFID tag that can measure elapsed time from initial state RFID tag search process to determine elapsed time It is a judgment step for the diagram according to the length and the length of the elapsed time. The lead determination referred to in claim 13 is made through a comparison step with an elapsed time (validity period) that is known to occur as corruption / degeneration. The remarks referred to in claim 14 include the steps in which the RFID tag is able to detect exposure to freshness inadequate temperature and is prepared / modified to measure elapsed time (ie, mounting a time-temperature module). .