WO2008072705A1

WO2008072705A1 - Acceleration sensor, and avian influenza monitoring system

Info

Publication number: WO2008072705A1
Application number: PCT/JP2007/074051
Authority: WO
Inventors: Takeshi Kobayashi; Toshihiro Itoh; Tsuyoshi Ikehara; Masaaki Ichiki; Ryutaro Maeda
Original assignee: National Institute Of Advanced Industrial Science And Technology
Priority date: 2006-12-15
Filing date: 2007-12-13
Publication date: 2008-06-19
Also published as: JP2008151562A; JP5071769B2

Abstract

Intended is to provide an acceleration sensor or the like capable of reducing the power requirements while reducing the size and weight. The acceleration sensor (210A) is constituted by connecting a plurality of piezoelectric material units (212) having a deformable member (211) deformed according to an acceleration applied, in series, and by connecting a signal processing circuit (213) with the piezoelectric material unit (212) at a predetermined position. To the signal processing circuit (213), there is applied a voltage according to the number of the piezoelectric material units (212), from the ground side acting as a reference potential to the piezoelectric material unit (212) connected with that signal processing circuit (213). If that voltage exceeds a preset voltage, a signal to turn ON the signal processing circuit (213) is outputted. On the basis of this signal, the acceleration can be digitally measured.

Description

Specification

Acceleration sensor, bird flu monitoring system

Technical field

[0001] The present invention relates to an acceleration sensor and an avian influenza monitoring system.

Background art

[0002] Conventionally, acceleration sensors measure the displacement of the mass part of the sensor by measuring the acceleration based on changes in capacitance, changes in electrical resistance due to the piezoresistance effect, strain gauges, changes in charge due to the piezoelectric effect, and the like. (For example, refer to patent documents;! To 3).

In recent years, such power! ] The speed sensor is miniaturized using micro electro mechanical systems (MEMS) technology.

[0003] Patent Document 1: Japanese Patent Laid-Open No. 2005-140720

Patent Document 2: JP 2006_250910A

Patent Document 3: Japanese Unexamined Patent Publication No. 2006-234795

Disclosure of the invention

Problems to be solved by the invention

[0004] Among the acceleration sensors as described above, those that detect capacitance and resistance change require driving power in order to measure acceleration. In other words, voltage is constantly applied, and changes in capacitance and resistance are detected based on normal capacitance and resistance. For this reason, depending on the application of the acceleration sensor, securing the power supply becomes a problem when it is attached to an acceleration measurement target. Especially in applications where such an acceleration sensor is worn on an animal, it is difficult to supply power from the outside or charge the battery, and the entire acceleration sensor including the power supply is downsized and lightweight. It is not possible to provide a large battery or the like.

The present invention has been made based on such a technical problem, and an object thereof is to provide an acceleration sensor and the like capable of reducing power consumption while allowing reduction in size and weight. And

Means for solving the problem [0005] For this purpose, the acceleration sensor of the present invention includes a deformable member that deforms according to acceleration, a piezoelectric material portion that is formed on the surface of the deformable member, and generates a charge according to deformation of the deformable member, A signal processing circuit for applying a voltage obtained according to the amount of electric charge generated in the piezoelectric material portion and generating a signal when the applied voltage exceeds a predetermined set voltage. A plurality of piezoelectric material portions are electrically connected in series to each other. Further, a plurality of signal processing circuits are provided, and are connected to at least two different piezoelectric material portions among the plurality of piezoelectric material portions connected in series. In each of the plurality of signal processing circuits, a voltage generated according to the number of piezoelectric material portions connected in series between the piezoelectric material portion to which the signal processing circuit is connected and the reference potential is applied. Caro is coming. Here, the piezoelectric material portion may include a piezoelectric thin film and a piezoelectric thick film, as well as a material that joins or bonds a composite material such as piezoelectric butter ceramics, single crystal, polymer, and composite.

In such an acceleration sensor, when an acceleration is applied, the deformable member is deformed, and accordingly, the piezoelectric material portion generates a charge corresponding to the amount of deformation. Since a plurality of the piezoelectric material parts are electrically connected in series, the number of piezoelectric material parts connected in series with the reference potential is determined by the arrangement (order) from the ground side. Depending on the voltage, the voltage varies depending on the 1S piezoelectric material part. When the voltage applied from the piezoelectric material part to the signal processing circuit exceeds the set voltage, the signal processing circuit emits a signal. By recognizing the signal processing circuit that issued this signal, the degree of the applied acceleration is obtained. be able to. In other words, acceleration can be measured digitally based on signals emitted from a plurality of signal processing circuits.

[0006] In such an acceleration sensor, signals from a plurality of signal processing circuits can be output via an electrical connection, or can be output via communication such as wireless communication. It can be stored in a memory circuit or the like.

[0007] By the way, the acceleration sensor as described above may be used for any purpose, but can be used for monitoring the bird influencer.

Recently, interest in “food safety” has been rapidly increasing due to the outbreak of BSE and the avian influenza epidemic in Japan. These problems are “safe for humans” ”, The symptomatic measures against individual infectious diseases, etc. from the viewpoint of the individual cannot be fundamentally solved. What is the power of food and the relationship between humans and nature (animals and plants)? There is a need to re-examine the problem from a global point of view!

[0008] As conventional methods for investigating the ecology of animals, there are known attempts to detect the estrus from the location of migratory birds using a GPS terminal and the walking frequency of cattle. In addition, off-line biopsy techniques have been mainly developed for conventional animal health management sensing. However, these methods cannot perform inspection quickly, are expensive, and cannot be widely used in general.

[0009] Therefore, the present inventors paid attention to changes in physical quantities of birds, such as acceleration, inclination, temperature, "blood flow, blood pressure" and pulse. A sensor that measures these physical quantities is attached to a bird to be managed, and the bird's health status is determined by determining the behavioral status of the bird based on the measurement result data transmitted from the sensor.

In such technology, physical sensors and communication devices can be housed in ultra-small chips by MEMS technology. By attaching such a chip to a large number of birds, collecting data sequentially, and analyzing the data using a computer, it is possible to manage a large number of birds at once.

[0010] In the course of further research, the present inventors have found that it is preferable to monitor changes in bird acceleration to determine bird health.

That is, the present invention is a bird flu monitoring system that is attached to a bird to be managed, measures at least acceleration, and wirelessly transmits the measurement result as data, and data transmitted from the sensor. And a determination device that determines whether or not an abnormality has occurred in the health condition of the bird!

[0011] The acceleration sensor of the present invention is suitable for use as described above.

That is, the sensor includes a deformable member that deforms in response to acceleration, a piezoelectric material portion that is formed on the surface of the deformable member and generates an electric charge according to the deformation of the deformable member, and an amount of charge generated in the piezoelectric material portion And a signal processing circuit that emits a signal when the applied voltage exceeds a predetermined set voltage, and the piezoelectric material portions are electrically connected to each other in series. A plurality of signal processing circuits are provided, Piezoelectric materials connected to at least two different piezoelectric material portions among the plurality of piezoelectric material portions connected in series, and connected in series with the reference potential in each of the plurality of signal processing circuits. The voltage generated according to the number of parts is applied.

At this time, the sensor is preferably configured to wirelessly transmit a signal only when the acceleration is equal to or higher than a predetermined set value.

In addition, the sensor preferably includes a remote power storage unit that stores the wirelessly supplied power.

In addition, in order to improve the detection accuracy of occurrence of avian influenza, the sensor may detect other parameters such as the body temperature of the bird in addition to the acceleration. The invention's effect

According to the acceleration sensor of the present invention, it is possible to measure acceleration digitally by detecting voltages output from a plurality of piezoelectric material portions connected in series with a plurality of signal processing circuits. . At this time, due to the applied acceleration, the piezoelectric material portion made of the piezoelectric material can directly generate an electric charge, so that the power consumption during standby can be reduced to almost zero. Moreover, since the amount of power generation when acceleration is applied can be increased by providing the piezoelectric material portions in series, this acceleration sensor can be highly sensitive. Furthermore, such an acceleration sensor can be made small by MEMS technology, and by reducing power consumption, it is possible to eliminate the battery and reduce the weight.

In addition, in the avian influenza monitoring system equipped with such an acceleration sensor, it is possible to reduce the weight of the sensor and to reduce the power consumption to extend the life of the sensor.

Brief Description of Drawings

FIG. 1 is a conceptual diagram of a bird flu monitoring system in the present embodiment.

FIG. 2 is a diagram showing a configuration of a sensor.

FIG. 3 is a diagram showing a specific configuration of the sensor.

FIG. 4 is a diagram showing a specific example of voltage change in the sensor.

Explanation of symbols [0014] 100 ··· Bird Infnore Yunza monitoring system, 120 ··· Sensor, 130 ··· Middle relay, 150 ··· Transmission / reception device, 160 ··· Control device (judgment computer), 210 ··· Physical quantity sensor, 210Α ... Acceleration sensor, 210T ... Temperature sensor, 211 ... Deformation member, 211a ... Cantilever, 211b ... Weight, 212 ... Piezoelectric material part (piezoelectric part), 213 ... Signal processing circuit, 220 ··· Sensor control unit, 230 ··· Capacitor, 240 ··· Communication control unit, 250 ·· 'Antenna

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail based on an embodiment shown in the accompanying drawings.

FIG. 1 is a diagram conceptually illustrating an avian influenza monitoring system 100 according to the present invention. As shown in FIG. 1, the avian influenza monitoring system 100 is attached to a bird (living body) managed in a management area 110. Sensors 120, one or more relay stations 130 installed to cover the management area 110, relay station controller 140 for centralized control of all the relay stations 130 installed in the management area 110, transmission / reception device 150 and control device (judgment computer) 160.

[0016] The management area 110 is provided for raising birds, such as a birdhouse.

In the management area 110, the sensor 120 and the relay station 130 communicate wirelessly. Therefore, the management area 110 is an area where the relay station 130 can acquire the signal from the sensor 120 directly or indirectly. Therefore, when the management area 110 is widened, the power to increase the wireless communication output of the sensor 120 and the number of relay stations 130 may be increased. It is preferable that one relay station 130 can cover an area having a radius of several tens of meters. There are standards such as IEEE802.llx wireless LAN, PHS (registered trademark), Bluetooth (registered trademark), ZigBee (registered trademark), and UWB as communication methods between the sensor 120 and the relay station 130. However, considering the balance between power consumption and communication distance, ZigBee (registered trademark) is now the preferred method. Of course, other methods may be used.

[0017] The sensor 120 is a high-density integration of a sensor group that detects the posture and behavior of a bird, vital signs, and the like, and a detection processing circuit, a communication circuit, a power supply, and a power management device, so as to monitor the health state of the bird. It is a system in package.

Measurement data in the sensor 120 is transmitted wirelessly. Transmitted measurement data The data is received by the relay station 130 and further transferred to the relay station controller 140.

[0018] The relay station 130 and the relay station controller 140 can be connected by wireless or wired Ethernet (registered trademark). The relay station controller 140 controls not only the relay station 130 installed in the management area 110 but also the relay stations in the other management areas 112 and 114, and collects and transmits the data of the sensors 120 received by these relay stations. Transfer to device 150. Furthermore, in addition to collecting data from the relay station 130, the relay station controller 140 is assigned an identification mark such as an IP address to all the relay stations 130 installed in the management area 110, and is provided with a control device. It is possible to add a function that mediates transmission of commands given from 160 to each sensor 120. In another embodiment, when a mesh network is formed by a plurality of relay stations 130, the relay station controller 140 can also be configured to control hand over between the relay stations 130.

The transmission / reception device 150 transmits the measurement data of the sensor 120 to the control device 160 through the Ethernet (registered trademark), the Internet, a telephone line, a wireless telephone network.

[0019] The control device 160 is a computer device in terms of hardware, and can be manufactured by installing software having necessary functions in a general-purpose computer. Therefore, many functions of the control device 160 are realized by cooperation of hardware such as CPU, memory, network adapter, and modem, which is provided in a general computer, and software.

Based on the measurement data transmitted from the sensor 120, the control device 160 monitors the presence / absence of the bird infuser. If it is determined that the measurement data 1S transmitted from the sensor 120 indicates the occurrence of avian influenza, the determination result, that is, information indicating that avian influenza has occurred, is output as an alarm output or printed matter. It can also be output by printing out or sending an e-mail to a pre-input destination. The control device 160 is installed in the vicinity of the management area 110! /, Or even! /, But it is installed in a remote place!

Next, the configuration of the sensor 120 will be described with reference to FIG.

FIG. 2 is a diagram showing the configuration of the sensor 120.

As shown in FIG. 2, for example, the sensor 120 has a predetermined physical property on a thin film substrate. A physical quantity sensor 210 for measuring the quantity, a sensor control unit 220 configured to control each part so as to perform a predetermined operation as the sensor 120, a capacitor 230 for storing electric power necessary for the operation of the sensor 120, This is an ultra-small network sensor chip in which a communication control unit 240 for performing communication control for transmitting / receiving radio waves to / from the relay station 130 and an antenna 250 are mounted on a thin-band (film-like) substrate.

Such a sensor 120 uses the most advanced ultra-high-density mounting technology and MEMS processing technology, and is also made extremely compact by narrowing down the sensor function. In one example, an ultra-small sensor chip is manufactured by a system-in-package with a three-dimensional multilayer chip (5 mm or less) in the middle lcm square area on a 3 cm square antenna FPC.

The physical quantity sensor 210 is a physical quantity sensing chip that measures at least acceleration. In the present embodiment, in addition to the acceleration sensor 210A, a temperature sensor 210T that detects the temperature (body temperature) of the object is provided as the physical quantity sensor 210.

[0022] In the sensor 120 of the present embodiment, the sensor information including acceleration information and temperature information detected by the acceleration sensor 210A and the temperature sensor 210T is not transmitted to the relay station 130 one after another. The ability to reduce power consumption by reducing the amount can be achieved. For example, in the temperature sensor 210T, sensor information is transmitted when the detected temperature deviates from the preset range and it can be determined that an abnormality has occurred in the state of the bird. Yes.

[0023] Specifically, the sensor control unit 220 includes an IC and a memory, and is a physical quantity sensor.

An event-driven circuit that performs predetermined processing when a signal is received from 210 is provided. Here, as the predetermined processing, there is a method of accumulating the contents of the signal received from the physical quantity sensor 210 in the memory.

Further, in the present embodiment, the sensor 120 generates electric power by the induced electromotive force by receiving the radio wave transmitted from the relay station 130 by the antenna 250, and stores this electric power in the capacitor 230. . For this reason, the sensor control unit 220 converts an RF-DC conversion circuit that converts radio waves received by the antenna 250 into a direct current, a charging circuit that stores electric power in the capacitor 230 by the direct current converted by the RF-DC conversion circuit, It has. In this way, sensor 120 is an active sensor that has a power supply and communicates with its own power. Therefore, it does not require scanning by a reader like RF—ID and it is never easy to control its behavior! /, Suitable for bird management! /.

[0024] The communication control unit 240 responsible for communication control functions as an ultra-compact wireless communication device for transmitting measurement data from the physical quantity sensor 210, and includes a control chip having a communication control circuit and And an impedance matching circuit for matching the impedance of radio waves to be transmitted and received. Here, the control chip is configured to have a unique identifier. When transmitting sensor information from the physical quantity sensor 210, the control chip is configured to transmit the identifier together.

FIG. 3 is a diagram showing a configuration of an acceleration sensor 210 A for detecting acceleration in the physical quantity sensor 210.

As shown in FIG. 3, the acceleration sensor 210A includes a deformation member 211 that deforms according to the acceleration applied to the acceleration sensor 210A, and a piezoelectric material portion 212 that generates an electric charge according to the deformation of the deformation member 211. A signal processing circuit 213 to which a voltage obtained according to the amount of electric charge generated in the piezoelectric material portion 212 is applied.

Here, as the deformable member 211, for example, a cantilever type composed of a cantilever 21 la and a weight 21 lb can be used. When acceleration is applied to the cantilever-type deformable member 211, the cantilever 21 la to which the mass of the weight 21 lb is added is squeezed and deformed with a deformation amount corresponding to the applied acceleration. Such a deformable member 211 is not limited to a cantilever type but may be another type such as a diaphragm type. Other types include, for example, a structure in which a weight is supported by a plurality of cantilevers (see Journal of Micromechanics and Microengineering, vol. 10, (2000) 322-328).

The piezoelectric material part 212 is made of a piezoelectric thin film formed on the surface of the deformable member 211. As a material for forming such a piezoelectric thin film, in addition to PZT (lead zirconate titanate) material, well-known piezoelectric materials such as Ba TiO, ZnO, A1N, quartz crystal, PVDF (polyvinylidene fluoride) are used.

Three

Is possible. When the deformable member 211 is deformed according to the applied acceleration, the piezoelectric material portion 212 generates an electric charge according to the deformation amount. That is, as the applied acceleration increases, the piezoelectric material portion 212 generates a larger charge. The voltage obtained in the piezoelectric material portion 212 is determined by the generated charge and the load capacity in the piezoelectric material portion 212. Here, if the cantilever 21 la is formed of, for example, a Si-based material, the piezoelectric material portion 212 may be formed by forming a thin film made of a predetermined piezoelectric material on the surface, and the cantilever 21 la itself. Can be made of a piezoelectric material, and the cantilever 21 la itself can be used as the piezoelectric material portion 212.

[0028] Such a deformable member 211 including the piezoelectric material portion 212 includes a plurality of the piezoelectric material portions 212 electrically connected in series in the acceleration sensor 210A, and one end side thereof is electrically grounded. Has been.

The signal processing circuit 213 is a MoS (Metal Oxide Semiconductor) transistor having a circuit configuration as shown in FIG. This signal processing circuit 213 can be provided in an IC constituting the sensor control unit 220.

As shown in FIG. 3, a plurality of such signal processing circuits 213 are connected to different deformation members 211 with respect to the deformation members 211 connected in series. Here, the signal processing circuit 213 may be less than the number of the deformable members 211 connected in series, or may be connected to all the deformable members 211. In the present embodiment, for example, 40 deformable members 211 are connected in series, and signal processing circuit 213 is connected to 4 deformable members 211 at positions previously extracted and selected. .

A voltage from the piezoelectric material part 212 of the deformable member 211 to which the signal processing circuit 213 is connected is applied to the gate of the signal processing circuit 213. Here, since the piezoelectric material portion 212 of the deformable member 211 is connected in series, the signal processing circuit 213 connected to the nth deformable member 211 from the ground side has a potential difference from the reference potential as the ground side. To the sum of voltage V (n XV) generated in n piezoelectric material sections 212 is applied.

Here, in each signal processing circuit 213, the voltage at which the transistor is turned ON is preset. That is, when the applied voltage exceeds the set voltage, the signal processing circuit 213 is turned on.

In the sensor control unit 220 to which the signal processing circuit 213 is connected, when the signal from the signal processing circuit 213 is switched from OFF to ON, or from ON to OFF, it is switched from OFF to ON, or from ON to OFF, and The time information is stored in the memory, and the stored information is transmitted to the control device 160 via the relay station 130 at a predetermined timing. It is supposed to send.

[0031] When acceleration acts on the acceleration sensor 210A, the individual deformable members 211 are similarly deformed, and therefore the same voltage is applied from each piezoelectric material portion 212. At this time, it is applied to the signal processing circuit 213 connected to the grounding side because the number of piezoelectric material portions 212 connected to the grounding side is small. The voltage is small. On the other hand, since the signal processing circuit 213 connected to the deformable member 211 far from the ground side has a large number of piezoelectric material parts 212 connected from the ground side, the applied voltage is growing.

[0032] With such a configuration, the applied voltage varies depending on the applied acceleration, so that the sensor control unit 220 recognizes which signal processing circuit 213 has been turned on to digitally determine the acceleration. Can be determined.

[0033] For example, according to the study by the present inventors, it is known that the acceleration caused by the bird's movement is 0.5 g during sleep, 0.2 g of cocoon, 0.5 g during meal, and lg during tremor.

If the sensitivity of the piezoelectric material portion 212 provided on the deformable member 211 is, for example, 1. lmV / g, when the sensor 120 is attached to a bird, the piezoelectric material portions 212 of the individual deformable members 211 may be As shown in Table 1, the output voltage is 0.055 mV, 0.22 mV, 0.55 mV, and 1. lmV.

[0034] [Table 1]

In the acceleration sensor 21 OA, the deformable member 211 including the piezoelectric material portion 212 is provided. For example, when 40 are connected in series and the signal processing circuit 213 is provided in the deformable member 211 of the n = 3rd, 10th, 15th, 40th from the ground side, depending on the behavior of the bird The applied voltage is as shown in Table 1.

Table 1 shows the signal processing circuits 213 that are turned on in response to bird operations when the voltage that is turned on in each signal processing circuit 213 is set to 2 mV. In other words, only the signal processing circuit 213 attached to the n = 40th deformable member 211 is ON during sleep.

(n = 40) The signal processing circuits 213 and 213 attached to the n = 15, 40th deformable member 211 are sometimes used, and n = 10, 15, 40th deformable material 211

(n = 15) (n = 40)

The signal processing circuits 213, 213, and 213 force S0N attached to So

(n = 10) (n = 15) (n = 40)

When the body shakes, all signal processing circuits 213, 213, 213, and 213 attached to the n = 3, 10, 15, 40th deformable member 211 are used.

(η = 3) (η = 10) (η = 15) (η = 40)

In this manner, in the sensor control unit 220 of the acceleration sensor 210A, it is possible to digitally obtain the acceleration level according to the number of signal processing circuits 213 that are turned on. For example, as shown in Table 1, when the signal processing circuit 213 force SON, level 1,

(n = 40)

Level 2 when signal processing circuits 213 and 213 are turned on, signal processing circuit 2

(n = 15) (n = 40)

13, 213, 213 When the force becomes ^ N, the level is 3 and the signal processing circuit 213

(n = 10) (n = 15) (n = 40) (n

, 213, 213, 213 Force ^ 〇N

= 3) (n = 10) (n = 15) (n = 40)

Thus, the acceleration level can be digitally determined.

[0037] FIG. 4 shows individual signal processing circuits 213 when the behavior of a bird is, for example, 15 minutes for a shark, 10 minutes for a meal, 30 minutes for sleep, and 5 minutes for a tremor. It shows the temporal displacement of the applied voltage. In this way, the signal processing circuits 213, 213, 21 when the tremor is started, which is an operation that can be determined that an abnormality has occurred in the state of the bird.

(n = 3) (n = 10)

3 and 213 are turned ON, and the acceleration level is

(n = 15) (n = 40)

4 can be determined.

The sensor 120 transmits sensor information when the temperature detected by the temperature sensor 210T deviates from the preset range and is a value that can be determined that an abnormality has occurred in the state of the bird. ing. That is, when the acceleration level is level 4 in the sensor control unit 220, the detected acceleration level is level 4 in the sensor 120. A signal indicating that is transmitted.

When the control device 160 receives a sensor 120 force, or a signal indicating that the acceleration level is level 4, it determines that an abnormality has occurred in the physical condition of the bird in the management area 110. .

In this case, all of the signal processing circuits 213, 213, 213, 213 are monitored.

(n = 3) (n = 10) (n = 15) (n = 40)

However, the sensor control unit 220 may monitor the signal processing circuit 213 that is turned on only when there is a tremor.

(n = 3)

In such an acceleration sensor 210A, due to the applied acceleration, the piezoelectric material portion 212 made of a piezoelectric material directly generates an electric charge, so the power consumption during standby is almost zero.

In addition, since the piezoelectric material portion 212 provided in the deformable member 211 is provided in series, the amount of power generated when acceleration is applied can be increased. Therefore, the acceleration sensor 210A must be highly sensitive. I'll do it.

In addition, by attaching such a sensor 120 to a bird and monitoring it wirelessly, it becomes possible to monitor the behavior of a large number of birds at low cost and online without interfering with the behavior of the birds. This makes it easy to understand the health status of birds and to quickly detect emergencies such as the occurrence of infectious diseases. Furthermore, such an acceleration sensor 210A can be formed in a small size by MEMS technology, and by reducing power consumption, it is possible to eliminate the battery and reduce the weight.

Here, of course, the sensitivity in the piezoelectric material section 212, the number of the deformable members 211, the set voltage to be turned on in the signal processing circuit 213, etc. are merely examples, and can be appropriately changed. By changing the number of deformation members 211 provided with the piezoelectric material part 212 provided in series, the connection position of the signal processing circuit 213, the set voltage in the signal processing circuit 213, etc. Can be measured. At this time, the individual deformable member 211, the piezoelectric material portion 212, and the signal processing circuit 213 themselves can be used in common, so that a device with high versatility and applicability can be used by simply changing the design according to the application. It can be said that it is a configuration.

[0039] While the preferred embodiments of the present invention have been described above with examples, the present invention has been described. It goes without saying that various embodiments can be taken in addition to the embodiments described herein without departing from the scope! /.

For example, the sensor 120 can be used for purposes other than monitoring avian influenza outbreaks. For example, it may be designed exclusively for the output of the “sensor type” communication device, etc., depending on its use, such as for bird farming “for livestock” and for wild animals. The sensor 120 can also be used to measure acceleration in other applications than in animals. In that case, if the subject to which the sensor 120 is attached is not difficult to control its operation, the sensor 120 can be configured to include a battery instead of supplying power by radio waves. Of course, this battery can be charged at an appropriate timing.

In addition to the above, the configurations described in the above embodiments can be selected or changed to other configurations as appropriate without departing from the gist of the present invention.

Claims

The scope of the claims

[1] a deformable member that deforms in response to acceleration;

A piezoelectric material part that is formed on the surface of the deformable member and generates an electric charge according to the deformation of the deformable member;

A voltage obtained according to the amount of charge generated in the piezoelectric material portion is applied, and a signal processing circuit that emits a signal when the applied voltage exceeds a predetermined set voltage, and

The piezoelectric material portions are electrically connected in series with each other, and a plurality of the signal processing circuits are provided. Among the plurality of piezoelectric material portions connected in series, at least two of the piezoelectric material portions are different from each other. Each of the plurality of signal processing circuits is connected to the piezoelectric material section and connected in series between the piezoelectric material section to which the signal processing circuit is connected and a reference potential. An acceleration sensor, wherein a voltage generated according to the number of the piezoelectric material portions is applied.

2. The acceleration sensor according to claim 1, wherein acceleration is digitally measured based on the signals emitted from the plurality of signal processing circuits.

[3] A bird flu monitoring system,

A sensor that is mounted on a bird to be managed, measures at least acceleration, and wirelessly transmits the result of the measurement as data;

A bird influencer comprising: a determination device that determines whether or not an abnormality has occurred in the health condition of the bird based on the data transmitted from the sensor; Monitoring system.

[4]

A deformable member that deforms in response to acceleration;

A voltage obtained according to the amount of charge generated in the piezoelectric material portion is applied, and a signal processing circuit that emits a signal when the applied voltage exceeds a predetermined set voltage, and The piezoelectric material portions are electrically connected in series with each other, and a plurality of the signal processing circuits are provided. Among the plurality of piezoelectric material portions connected in series, at least two of the piezoelectric material portions are different from each other. A voltage generated according to the number of the piezoelectric material portions connected in series with a reference potential is applied to each of the plurality of signal processing circuits connected to the piezoelectric material portion. The avian influenza monitoring system according to claim 3.

[5] The bird flu monitoring according to claim 3 or 4, wherein the sensor is configured to wirelessly transmit a signal only when the acceleration is greater than or less than a predetermined set value. system.

6. The avian influenza monitoring system according to any one of claims 3 to 5, wherein the sensor includes a remote power storage unit that stores wirelessly supplied power.