JP5522015B2 - Multipoint measurement data acquisition apparatus, multipoint measurement system, and multipoint measurement data acquisition method - Google Patents

Description

  The present disclosure relates to a multipoint measurement data acquisition device, a multipoint measurement system, and a multipoint measurement data acquisition method for acquiring measurement results at a plurality of points.

  In order to properly manage fields such as so-called fields, a multi-point measurement system that installs sensors that measure water content and fertilizer concentration at many points in the field and obtains measurement data at many points is proposed. Has been.

  In such a multipoint measurement system, it is desirable to obtain the measurement data at each position after grasping the position of each installed sensor.

  As a technique for grasping the installation position of each sensor included in the multipoint measurement system, a method of registering the position information of each sensor at the time of installation has been proposed (see Patent Document 1). Various techniques have been proposed as techniques for collecting measurement data obtained by sensors. One of them is a method of receiving a wireless signal transmitted from each sensor by a measurement data acquisition device (see Patent Documents 1 and 2). Further, a method of collecting via a serial cable connecting each sensor and a measurement data acquisition device has been proposed (see Patent Document 3). A technique has also been proposed in which measurement data from a plurality of sensors is collected in a collective manner using a single cable (see Patent Document 3).

Japanese Patent Laying-Open No. 2005-085059 JP 2007-333705 A Japanese Patent Publication No.7-120480

  When a large number of sensor units are installed on a wide field, the work of registering the installation location of each sensor unit is complicated even if a position specifying service such as GPS (Global Positioning System) is used. In order to transmit a radio signal including measurement data from each sensor unit, it is necessary to expose at least the antenna portion of each sensor unit to the ground. However, when there is a portion exposed on the ground in this way, there may be a problem in the work on the field.

  The apparatus and method of the present disclosure are intended to provide a multipoint measurement data acquisition device, a multipoint measurement system, and a multipoint measurement data acquisition method that can collect the positions of a plurality of sensor units embedded in a farm field after installation. To do.

  The above-described object can be achieved by a multipoint measurement data acquisition device, a multipoint measurement system, and a multipoint measurement method disclosed below.

  The multi-point measurement data acquisition device according to one aspect includes a position where each of the sensor units is fixed and the transmission from a response returned through each of the plurality of sensor units fixed to one transmission path. An information extraction unit that extracts information including a distance from one end of the path and information on a bending direction of the transmission path at a fixed position of each sensor unit; and the plurality of information based on the information extracted by the information extraction unit An arrangement estimation unit for estimating the arrangement of the sensor units.

  In addition, the multipoint measurement system according to another aspect includes a plurality of sensor units fixed to one transmission path, and a response returned from each of the plurality of sensor units via the transmission path. An information extraction unit for extracting information including a distance between a fixed position and one end of the transmission path and information on a bending direction of the transmission path at a fixed position of each sensor unit; and the information extraction unit And an arrangement estimating unit that estimates the arrangement of the plurality of sensor units based on the information.

  Further, the multipoint measurement method according to another aspect collects responses returned through the transmission path by each of a plurality of sensor units fixed to one transmission path, and each sensor unit is obtained from the collected responses. Information including the distance between the fixed position and one end of the transmission path and information regarding the bending direction of the transmission path at the fixed position of each sensor unit, and based on the extracted information, The position where measurement data is acquired by each sensor unit is estimated.

  According to the device and method of the present disclosure, the positions of a plurality of sensor units embedded in a farm can be collected after installation.

It is a figure which shows one Embodiment of a multipoint measuring system. It is a figure explaining an example of arrangement | positioning estimation processing. It is a figure which shows another embodiment of a multipoint measuring system. It is a flowchart showing a positional information collection operation | movement. It is a flowchart showing a position information notification operation. It is a flowchart showing coordinate calculation operation. It is a figure explaining a coordinate calculation process. It is a figure which shows another embodiment of a sensor unit. It is a figure which shows another embodiment of a multipoint measuring system. It is a figure which shows another embodiment of a multipoint measuring system. It is a figure which shows another embodiment of a sensor unit. It is a figure explaining another embodiment of a sensor unit. It is a flowchart showing another embodiment of position information collection operation | movement. It is a figure which shows another embodiment of a multipoint measuring system.

Hereinafter, embodiments of the multipoint measurement data acquisition device, multipoint measurement system, and multipoint measurement data acquisition method of the present disclosure will be described in detail based on the drawings.
(One embodiment of multipoint measurement system)
FIG. 1 shows an embodiment of a multipoint measurement system.

  In the example illustrated in FIG. 1, the multipoint measurement system includes a plurality of sensor units 101, a transmission path 102, and a multipoint measurement data acquisition device 110. A plurality of sensor units 101 shown in FIG. 1 are fixed in close proximity to one transmission path 102. In FIG. 1, illustration of a holder for fixing each sensor unit 101 to the transmission path 102 is omitted.

  In the example shown in FIG. 1, a high-frequency power supply line including, for example, a single-wire or parallel two-wire power supply line, a coaxial power supply line, a leaky coaxial cable, and the like is used as the transmission path 102. Each sensor unit 101 receives a signal from the multipoint measurement data acquisition device 110 by receiving a high-frequency signal leaking from the transmission path 102. Each sensor unit 101 sends a signal to the multipoint measurement data acquisition device 110 by leaking a high-frequency signal to the transmission path 102.

  That is, communication between each sensor unit 101 and the multipoint measurement data acquisition device 110 shown in FIG. 1 is performed using the transmission path 102 and high-frequency leakage between the transmission path 102 and each sensor unit 101. Is called. In such a configuration, each sensor unit 101 and the transmission path 102 may be fixed so as to be close enough to allow signal transmission by high-frequency leakage.

  In addition, the multipoint measurement data acquisition apparatus 110 illustrated in FIG. 1 includes an information extraction unit 111, an arrangement estimation unit 112, and a measurement data collection unit 117. In the embodiment shown in FIG. 1, the information extraction unit 111 includes a transmission / reception unit 113, a request transmission unit 114, a response detection unit 115, and a transmission path length calculation unit 116. The arrangement estimation unit 112 includes an arrangement information table 118, a rearrangement unit 119, and a vector addition unit 120.

  The request sending unit 114 included in the information extracting unit 111 performs a process of sending a request signal for requesting notification of position information to each sensor unit 101. This request signal is transmitted to the transmission line 102 by the transmission / reception unit 113 using high-frequency leakage. Then, the request signal described above is transmitted to each sensor unit 101 through this transmission path 102. In addition, the time t1 at which the above-described request signal is transmitted is notified to the transmission path length calculation unit 116 by the request transmission unit 114.

  Similarly, the response signal from each sensor unit 101 is transmitted to the transmission / reception unit 113 due to high-frequency leakage from the transmission path 102. The response detection unit 115 detects information indicating the time t2 when the response signal from each sensor unit 101 arrives at the transmission / reception unit 113 and the bending direction of the transmission path 102 included in the response signal. In addition, the response detection unit 115 notifies the transmission path length calculation unit 116 of the response signal arrival time t2. On the other hand, information indicating the bending direction is notified from the response detection unit 115 to the arrangement estimation unit 112.

  The transmission path length calculation unit 116 transmits the transmission path between the sensor unit 101 that returned the response signal and the multipoint measurement data acquisition apparatus 110 based on the request signal transmission time t1 and the response signal arrival time t2. The length L is calculated. For example, the transmission path length L can be expressed as in Expression (1) using the delay time Δt until the response in the sensor unit 101 and the propagation speed v of the high-frequency signal in the transmission path 102. In Equation (1), the propagation speed v of the high-frequency signal is replaced with the product of the speed of light c and a constant α.

L = (t2−t1−Δt) × (α × c) / 2 (1)
The arrangement information table 118 of the arrangement estimation unit 112 holds position information including the transmission path length to each sensor unit 101 calculated by the transmission path length calculation unit 116 and the bending direction notified from the response detection unit 115. . For example, the arrangement information table 118 can hold the above-described position information corresponding to an ID (Identifier) that identifies each sensor unit 101. The ID of each sensor unit 101 can be set in advance so as to be unique in the multipoint measurement system, for example. The rearrangement unit 119 rearranges the position information stored in the arrangement information table 118 based on the transmission path length. For example, the rearrangement unit 119 can rearrange the pairs of the IDs of the sensor units 101 and the position information in the order of shorter transmission path lengths. The vector adding unit 120 obtains a vector corresponding to the displacement between each sensor unit 101 and the adjacent sensor unit 101 in the order of the transmission path length based on the rearranged position information. Further, the vector addition unit 120 calculates the coordinates indicating the two-dimensional or three-dimensional arrangement of each sensor unit 101 by sequentially adding the obtained vectors. The calculated coordinates are stored in the arrangement information table 118 corresponding to the ID of the sensor unit 101. Therefore, the measurement data acquisition unit 117 can obtain the arrangement information indicating the position of each sensor unit 101 by referring to the arrangement information table 118. Details of the process for estimating the arrangement of each sensor unit 101 will be described later.

  The measurement data acquisition unit 117 receives measurement data from each sensor unit 101 via the transmission / reception unit 113 described above. These measurement data are associated with the position of each sensor unit 101 indicated by the above-described arrangement information in the measurement data acquisition unit 117.

  As described above, information for specifying the position of each sensor unit 101 from the response from each sensor unit 101 after the plurality of sensor units 101 is installed on the field by the information extraction unit 111 as shown in FIG. Can be collected. Based on the collected information, the position estimation unit 112 can determine the position of each sensor unit 101.

  Thereby, it is possible to save labor for installing a large number of sensor units in a vast field. This is because the operation of registering the position of each sensor unit 101 can be omitted when each sensor unit 101 is installed.

  Further, in a configuration that performs communication using high-frequency leakage, it is not necessary to physically connect each sensor unit 101 and the transmission path 102. This feature is very useful when the plurality of sensor units 101 and the transmission path 102 are embedded in an environment with much moisture such as a farm field. This is because it is not necessary to provide a joint such as a waterproof connector between each sensor unit 101 and the transmission path 102. Thereby, the cost reduction of each sensor unit 101 and the improvement of reliability can be aimed at.

  Next, processing for estimating the position of each sensor unit 101 by the placement estimation unit 112 based on the information collected as described above will be described.

  FIG. 2 is a diagram illustrating an example of the arrangement estimation process. In the example shown in FIG. 2, each sensor unit 101 is denoted by reference numerals S <b> 1 to S <b> 10. Further, the bending direction of the transmission path 102 at the position of each sensor unit 101 is indicated by a value obtained by measuring the angle formed by the transmission path 102 entering the sensor unit 101 and the outgoing transmission path 102 counterclockwise. It is.

  FIG. 2A shows an arrangement example of the multipoint measurement system having the sensor units S1 to S10 and the multipoint measurement data acquisition device 110. FIG. 2B shows the angles indicating the bending direction included in the response and the response times τ1 to τ10 from when the request is sent until the response arrives, corresponding to each of the sensor units S1 to S10. The response time corresponds to the difference (t2−t1) between the request signal transmission time t1 detected for each sensor unit and the response signal arrival time t2.

  Therefore, based on the response times τ1 to τ10 corresponding to the sensor units S1 to S10, the transmission path lengths L1 to L10 between the multipoint measurement data acquisition device 110 and the sensor units S1 to S10 can be obtained. For example, the transmission path length between the sensor units S1 and S2 can be obtained by subtracting the transmission path length L1 from the transmission path length L2. Further, the direction in which the sensor unit S2 is viewed from the sensor unit S1 can be determined from the bending direction indicated by the response from the sensor unit S1. From these pieces of information, the vector adding unit 120 described above can obtain a vector for specifying the position of the sensor unit S2 with reference to the position of the sensor unit S1. Then, the vector adding unit 120 adds the obtained vector to the coordinates indicating the position of the sensor unit S1, thereby obtaining the coordinates indicating the position of the sensor unit S2. By repeating the same processing for the sensor units S3 to S10, the positions of these sensor units S3 to S10 can be specified sequentially.

  In the example shown in FIG. 2, the sensor units S1 to S10 are arranged on the same plane. Further, the transmission path 102 is arranged at a position of the sensor unit 101 so as to be bent in units of 90 degrees. In this case, the process of estimating the position of each sensor unit 101 can be realized by a process of adding or subtracting the transmission path length between adjacent sensor units 101 in the coordinate axis direction.

The above-described processing by the information extraction unit 111 and the processing by the arrangement estimation unit 112 can be realized by, for example, the multipoint measurement data acquisition device 110 having a microcontroller. Similarly, each sensor unit 101 may be provided with a microcontroller to control processing for sending a response including the bending direction.
(Another embodiment of the multipoint measurement system)
FIG. 3 shows another embodiment of the multipoint measurement system. 3 that are equivalent to the components shown in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

  The multipoint measurement data acquisition device 110 illustrated in FIG. 3 includes a microcontroller 201, a memory 202, and a transmission / reception unit 210. The transmission / reception unit 210 illustrated in FIG. 3 corresponds to the transmission / reception unit 113 illustrated in FIG. 1.

  The sensor unit 101 includes a temperature sensor 221, a moisture sensor 222, a temperature measurement unit 223, a soil moisture measurement unit 224, a microcontroller 225, a memory 226, and a transmission / reception unit 210. In FIG. 3, one embodiment is shown for one sensor unit 101, and illustration of the other sensor unit 101 is omitted. The sensor unit 101 (not shown) can be configured in the same manner as the sensor unit 101 shown in FIG.

  The transmission / reception units 210 of the multi-point measurement data acquisition device 110 and the sensor unit 101 are both disposed close to the transmission path 102. In the transmission / reception unit 210, the high-frequency signal generated by the modulation by the modulator 211 is amplified by the amplifier 212 and then transmitted by the transmission antenna 213. This high frequency signal is transmitted to the transmission line 102 by high frequency leakage. A high frequency signal transmitted through the transmission path 102 is transmitted to the receiving antenna 214 of the transmission / reception unit 210 due to high frequency leakage. The received signal that has reached the receiving antenna 214 is amplified by the amplifier 215 and then demodulated by the demodulator 216.

  In the multipoint measurement data acquisition apparatus 110, the modulator 211 and the demodulator 216 of the transmission / reception unit 210 are connected to the microcontroller 201. In the sensor unit 101, the modulator 211 and the demodulator 216 of the transmission / reception unit 210 are connected to the microcontroller 225.

  In the sensor unit 101, the output of the temperature sensor 221 is sent to the microcontroller 225 via the temperature measurement unit 223. Similarly, the output of the moisture sensor 222 is also sent to the microcontroller 225 via the soil moisture measuring unit 224. In addition to the temperature sensor 221 and the moisture sensor 222 described above, a sensor for acquiring various data representing the state of the soil can be arranged in the sensor unit 101. Further, the number of sensors arranged in the sensor unit 101 may be one, or three or more.

  Further, the memory 226 included in the sensor unit 101 has an ID holding unit 227. As the ID held in the ID holding unit 227, for example, identification information unique to the sensor unit 101 such as a serial number can be used. The memory 226 also includes an angle information holding unit 228 that holds angle information indicating the bending direction of the transmission path 102 at the position of the sensor unit 101. A method for setting angle information in the angle information holding unit 228 will be described later.

  The microcontroller 225 generates a response signal using the ID and angle information held in the memory 226 in response to the request signal received via the demodulator 216 included in the sensor unit 101. This response signal is input to the modulator 211 included in the sensor unit 101.

  Next, an operation of collecting position information by processing of the microcontroller 201 of the multipoint measurement data acquisition apparatus 110 and the microcontroller 225 of the sensor unit 101 will be described.

  FIG. 4 is a flowchart showing the position information collection operation. FIG. 5 is a flowchart showing the position information notification operation. 4 and 5 show an example in which the sensor unit 101 specified in the request returns a response signal including angle information in response to a request from the multipoint measurement data acquisition device 110. FIG.

  First, the microcontroller 201 included in the multipoint measurement data acquisition apparatus 110 transmits a request signal including one of IDs that designate a plurality of sensor units 101 as destinations via the transmission / reception unit 210 (step 301). For example, the microcontroller 201 can select the IDs included in the request signal sequentially from the list of IDs of the sensor units 101 prepared in the memory 202. Note that such a list of IDs can be prepared for the sensor unit 101 that may be registered in the multipoint measurement system, for example, before starting the position information collection operation.

  Next, the microcontroller 201 starts measuring the response time from the sensor unit 101 corresponding to the ID (step 302). When the response from the designated sensor unit 101 is detected (affirmative determination in step 303), the microcontroller 201 proceeds to step 304.

  In step 304, the microcontroller 201 calculates the transmission path length from the response time to the sensor unit 101 corresponding to the specified ID using the above-described equation (1). Note that the accuracy of the transmission length calculated from the response time using the equation (1) is limited by the measurement accuracy of the response time. Therefore, it is desirable that the transmission / reception unit 210 included in the multipoint measurement data acquisition device 110 and each sensor unit 101 has a function of transmitting / receiving an impulse train that can measure response time with high accuracy.

  Next, the microcontroller 201 holds the position information including the angle information included in the detected response and the transmission path length calculated in step 304 in the memory 202 corresponding to the ID described above (step 305). . Thereafter, the processing proceeds to step 306.

  On the other hand, when the response signal is not detected (No determination in step 303), the microcontroller 201 determines that the sensor unit 101 designated as the destination does not exist in the multipoint measurement system. For example, the microcontroller 201 can determine that the response signal is not detected when the response signal does not arrive even after a predetermined time has elapsed since the request signal was transmitted in step 301. The predetermined time described above can be determined in advance based on the total length of the transmission path 102 used in the multipoint measurement system. If the determination in step 303 is negative, the process skips steps 304 and 305 and proceeds to step 306.

  In step 306, the microcontroller 201 determines whether or not the transmission of the request signal addressed to all the sensor units 101 in the above-described ID list has been completed. If there is a sensor unit that has not yet been designated as the destination (No in Step 306), the microcontroller 201 returns to Step 301 and continues the processing. At this time, the microcontroller 201 updates the destination ID, for example, according to the above-described list of IDs (step 307).

  Steps 301 to 307 described above are repeatedly executed, and when processing for all IDs included in the list of IDs is completed (affirmative determination in step 306), the processing proceeds to step 308.

  In step 308, the microcontroller 201 rearranges the position information held in the memory 202 in the order of the transmission path length. As in the example of the multipoint measurement data acquisition device 110 illustrated in FIG. 3, the configuration in which the microcontroller 201 executes step 308 described above is an example of the rearrangement unit 119 illustrated in FIG. 1.

  Next, the microcontroller 201 calculates coordinates indicating the position of each sensor unit based on the transmission path length and the angle information as described with reference to FIG. 2 (step 309). A specific example of the method for calculating the coordinates will be described later.

  Then, the microcontroller 201 stores the coordinates calculated for each sensor unit 101 in the memory 202 corresponding to each ID, thereby generating arrangement information indicating the arrangement of the plurality of sensor units 101. (Step 310).

  On the other hand, the microcontroller 225 included in the sensor unit 101 sets angle information in the angle information holding unit 228 of the memory 226 when the sensor unit 101 is installed (step 311 in FIG. 5).

  Thereafter, step 312 is repeated to wait for the arrival of the request signal. When a request signal that propagates through the transmission path 102 arrives (affirmative determination at step 312), a request signal including an ID is passed from the demodulator 216 of the transmission / reception unit 210 to the microcontroller 225.

  In response to this, the microcontroller 225 extracts the ID indicating the destination from the request signal (step 313). If the extracted ID does not match the ID of the own device held in the ID holding unit 227 of the memory 226 (No determination in step 314), the microcontroller 225 determines that the request signal is not addressed to the own device. To do. In this case, the process returns to step 312 to continue the process of waiting for a new request signal.

  On the other hand, when the extracted ID matches the ID of the own device held in the ID holding unit 227 of the memory 226 (Yes in step 314), the microcontroller 225 determines that the request signal is addressed to the own device. to decide. In this case, the microcontroller 225 generates a response signal including the angle information held in the memory 226. Then, the generated response signal is transmitted via the transmission / reception unit 210 (step 315).

  As described above, the arrangement information of each sensor unit 101 is installed after each sensor unit 101 is installed by exchanging the request signal and the response signal between the multipoint measurement data acquisition device 110 and each sensor unit 101. Can be collected.

  The coordinates of each sensor unit 101 included in the arrangement information can be calculated as described below.

  FIG. 6 is a flowchart showing the coordinate calculation operation. FIG. 7 shows a diagram for explaining the coordinate calculation process. In FIGS. 6 and 7, the j-th sensor unit is denoted by S (j) in order of increasing transmission path length. The position information corresponding to the j-th sensor unit is indicated by an angle A (j) and a transmission path length L (j).

  In step 321 shown in FIG. 6, the microcontroller 201 sets an initial value to the coordinate P (x, y). At this time, the initial value 1 is set to the variable j. Further, the coordinates P (x, y) described above are stored in the memory 202 as the position of the sensor unit S (1) closest to the multipoint measurement data acquisition device 110.

  Next, the microcontroller 201 calculates the difference D (j) between the transmission path lengths L (j) and L (j + 1) held in the memory 202 corresponding to the jth and j + 1th sensor units (step 322). . This difference D (j) indicates the distance between the jth sensor unit and the j + 1th sensor unit.

Next, based on the difference D (j) and the angle A (j) held in the memory 202 corresponding to the jth sensor unit, the microcontroller 201 determines that the j + 1th sensor from the jth sensor unit. A vector V (x _j , y _j ) toward the unit is obtained (step 323).

For example, in the example shown in FIG. 7, the coordinate axis with the position of the sensor unit S (1) as the origin matches the direction of the transmission path 102 entering the sensor unit S (1) and the direction of the X axis. Has been placed. Thus, if the position of the sensor unit S (1) closest to the multipoint measurement data acquisition device 110 is used as a reference, the sensor unit S is based on the angle A (1) corresponding to the sensor unit S (1). (1) from toward the sensor unit S (2) vector V (x _1, y ₁₎ and the angle theta (1) the x-axis can be obtained. The angle θ (1) and the length of the vector V (x ₁ , y ₁ ) are the transmission path lengths L (1) and L (2) corresponding to the sensor units S (1) and S (2). By using the difference D (1), the vector (x ₁ , y ₁ ) can be calculated. Similarly, a vector V (x _j , y _j ) from the jth sensor unit S (j) to the j + 1th sensor unit can be obtained.

The vector V (x _j , y _j ) obtained in this way is added to the coordinates P (x, y) described above by the microcontroller 201 (step 324). For example, by adding the vector V (x ₁ , y ₁ ) from the sensor unit S (1) to the sensor unit S (2) to the coordinates P (x, y) whose initial values are set in step 321, Coordinates indicating the position of the sensor unit S (2) can be obtained. Similarly, when the coordinate P (x, y) indicates the position of the j-th sensor unit, the vector V (x _j , y _j ) is added to the coordinate P (x, y) to obtain the j + 1-th position. The coordinates indicating the position of the sensor unit can be calculated.

  The configuration in which the microcontroller 201 performs the processing from step 322 to step 324 in this way is an example of the vector addition unit 120 illustrated in FIG.

  The coordinates P (x, y) obtained as the addition result in step 324 is stored in the memory 202 as the position of the sensor unit S (j + 1) by the microcontroller 201 (step 325).

  Thereafter, the microcontroller 201 determines whether or not the processing for all the sensor units 101 has been completed (step 326). For example, the microcontroller 201 can make the determination in step 326 by comparing the number N of sensor units that have detected the response signal with the variable j.

  In the case of negative determination in step 326, the microcontroller 201 updates the variable j, returns to step 322, and then performs processing based on the position of the sensor unit 101 close to the multipoint measurement data acquisition device 110.

  By repeating the processes in steps 322 to 327 described above, the position of each sensor unit 101 can be specified in the order closer to the multipoint measurement data acquisition device 110. When the position specification for all the sensor units 101 is completed, the microcontroller 201 ends the position information collection process as an affirmative determination in step 326.

  In this way, according to the multipoint measurement system disclosed herein, the position information of each sensor unit 101 can be collected after the plurality of sensor units 101 are installed. Therefore, according to the multipoint measurement system disclosed in the present disclosure, it is not necessary to perform complicated operations such as individually registering position information when installing each sensor unit 101. Such a feature is very useful when a large number of sensor units 101 are installed together in a large-scale field.

  Further, the three-dimensional arrangement of each sensor unit 101 can be estimated by the above-described arrangement estimation process. In this case, for example, the multipoint measurement data acquisition device 110 may receive notification of information indicating a change in height from the sensor unit 101 installed at a position different from the installation position of the adjacent sensor unit 101. . Then, by reflecting the change in the height of the coordinates of each sensor unit 101 whose transmission path length is longer than the sensor unit to which the change in height is notified by the arrangement estimation unit 112, 3 of each sensor unit 101 is reflected. Coordinates indicating the arrangement in the dimension can be calculated.

As a method of setting angle information in the memory 226 of each sensor unit 101, the method described below can be considered.
(Another embodiment of sensor unit)
FIG. 8 shows another embodiment of the sensor unit. 8 that are the same as those shown in FIG. 1 and FIG. 3 are given the same reference numerals, and descriptions thereof are omitted.

  FIG. 8A is a plan view of another embodiment of the sensor unit 101. FIG. 8B is a right side view of another embodiment of the sensor unit 101. FIG. 8C is a front view of another embodiment of the sensor unit 101.

  In the example shown in FIG. 8, the control circuit unit 230 included in the sensor unit 101 is enclosed in a waterproof case. A groove 231 having a width enough to accommodate a coaxial cable used as the transmission path 102 is formed on the upper surface of the case. In the example shown in FIG. 8, the groove 231 is formed so as to be orthogonal to the central portion of the case. The control circuit unit 230 enclosed in the case includes the temperature measurement unit 223, the soil moisture measurement unit 224, the microcontroller 225, the memory 226, and a part of the transmission / reception unit 210 shown in FIG. Yes.

  Further, a claw-shaped transmission path holding portion 232 is provided at a position near the outer periphery of the case of the groove 231 described above. The transmission path holding unit 232 holds the transmission path 102 in a pushed state when the transmission path 102 is pushed into the groove 231. Further, as in the example shown in FIG. 8, the transmission path 102 can be stably held in the groove 231 by being restrained by a screw-type cover 233.

  As described above, the mechanism for holding the transmission path 102 on the upper surface of the sensor unit 101 can maintain the state where the transmission path 102 is bent, for example, in units of 90 degrees at the position of the sensor unit 101. In the example shown in FIG. 8A, the angle formed between the transmission path 102 entering the sensor unit 101 and the outgoing transmission path 102 is 180 degrees. On the other hand, FIG. 8D shows an example in which the transmission path 102 entering the sensor unit 101 and the outgoing transmission path 102 form 270 degrees.

  Further, as shown in FIG. 8A, a mark indicating the direction in which the transmission path 102 is inserted into the sensor unit 101 is attached corresponding to the transmission path holding portion 232 provided in one of the grooves 231 of the sensor unit 101. You can also keep it. In the example of FIG. 8A, facing triangles are attached as the above-described marks. The transmitting / receiving antenna 234 of the sensor unit 101 can be disposed at a position corresponding to the groove 231 indicated by the mark. The transmission / reception antenna 234 includes the transmission antenna 213 and the reception antenna 214 shown in FIG. If the transmission path 102 is inserted according to this mark when the sensor unit 101 is installed, the transmission / reception antenna 234 and the transmission path 102 included in the sensor unit 101 are automatically arranged close to each other.

  Further, the angle information indicating the bending direction of the transmission path 102 at the position of the sensor unit 101 is set in the memory 226 (see FIG. 3) in the sensor unit 101 by mechanically pushing the transmission path 102 into the groove 231 described above. You can also

  For example, the direction information generation unit 236 illustrated in FIG. 8B includes a switch 235 and a microcontroller (MC) 225 provided at each branch of the cross-shaped groove 231. For example, as shown in FIGS. 8A and 8D, these switches 235 can be provided so as to be operated as the transmission path 102 is inserted corresponding to the transmission path holding unit 232. Information indicating whether or not these switches 235 are operated is collected by the microcontroller 225. Based on the collected information and the positional relationship of each branch in the groove 231 described above, the microcontroller 225 can generate angle information indicating the bending direction of the transmission path 102 inserted in the sensor unit 101. The angle information generated in this way is held in the angle information holding unit 228 of the memory 226.

  The shape of the groove 231 formed in the case of the sensor unit 101 is not limited to the cross shape shown in FIG. For example, a groove that branches in the N direction (N is a natural number) from the center of the case can be formed. Furthermore, for example, the branching of the grooves can be asymmetrically arranged so that the grooves branch into a large number on the side far from the multipoint measurement data acquisition device 110.

  Instead of forming the groove 231 by recessing the case, for example, a guide that holds the transmission path 102 on the upper surface of the case and can be freely bent in a planar shape parallel to the upper surface can be provided. Then, it is possible to cause the microcontroller 225 included in the control circuit unit 231 to acquire angle information indicating the bending direction of the transmission path 102 using a mechanism for bending the guide.

  The coordinate calculation processing described with reference to FIGS. 6 and 7 can be applied even when the angle information notified from each sensor unit 101 indicates an arbitrary angle other than the unit of right angle. Therefore, the multipoint measurement system disclosed herein collects position information of individual sensor units 101 based on response signals notified from a plurality of sensor units 101 that are irregularly installed in an irregularly shaped farm field. can do.

  FIG. 9 shows another embodiment of the multipoint measurement system. 9 that are the same as those shown in FIG. 1 are given the same reference numerals, and descriptions thereof are omitted. Further, in FIG. 9, each sensor unit 101 is indicated by white circles or black circles with reference numerals S <b> 1 to S <b> 11 in which numbers in the order close to the multipoint measurement data acquisition device 110 and reference numerals S are combined.

  Among the sensor units S1 to S11 shown in FIG. 9, the sensor units S2, S5, S8, S9, and S11 whose angle information is 180 degrees are indicated by black circles. On the other hand, the angle information of the sensor units S1, S3, S4, S6, S7, and S10 indicated by white circles in FIG. 9 is indicated by a symbol combining the symbol A and a corresponding number.

  Here, when the angle information of the j-th sensor unit Sj is 180 degrees, the direction of the transmission path 102 does not change before and after the sensor unit Sj. That is, the microcontroller 201 of the multipoint measurement data acquisition apparatus 110 can calculate the position of the sensor unit Sj + 1 based on the distance to the sensor unit Sj + 1 and the direction of the transmission path 102 leading to the sensor unit Sj.

  Therefore, the sensor units S2, S5, S8, S9, and S11 indicated by black circles in FIG. 9 can return a response signal in which the angle information is omitted in response to the request signal from the multipoint measurement data acquisition device 110.

  In addition, the sensor units 101 can be linearly arranged along the plurality of transmission paths 102. In this case, the two-dimensional arrangement of each sensor unit 101 can be specified based on the transmission path length between these sensor units 101 and the multipoint measurement data acquisition device 110.

  FIG. 10 shows another embodiment of the multipoint measurement system. 10 that are equivalent to the components shown in FIG. 1 are denoted by the same reference numerals and description thereof is omitted.

  The multipoint measurement data acquisition apparatus 110 illustrated in FIG. 10 is connected to m transmission lines 102 via a switch 103. The switch 103 connects the terminal T0 connected to the multipoint measurement data acquisition device 110 to any one of the terminals T1 to Tm corresponding to the m transmission paths 102, respectively. Switching of the connection terminal in the switch 103 can be performed according to an instruction from the multipoint measurement data acquisition device 110.

  In the m transmission lines 102, n sensor units 101 are fixed, respectively. In FIG. 10, the k-th sensor unit fixed to the transmission line 102 corresponding to the terminal Tj is indicated by a reference symbol Sjk.

  The multipoint measurement data acquisition device 110 shown in FIG. 10 is a response signal returned by the sensor units Sj1 to Sjn fixed to the j-th transmission line 102 in a state where the terminals T0 and Tj are connected by the switch 103. Can be collected. And based on the response time corresponding to these response signals, the transmission path length to these sensor units Sj1-Sjn is calculated.

  In the example of FIG. 10, the transmission paths 102 are installed in parallel to each other. The direction of each transmission path 102 toward the point where the m transmission paths 102 are converged by the switch 103 is orthogonal to the direction of the transmission path 102 in the section where the sensor unit 101 is fixed. In the case of such an arrangement, for example, the arrangement of individual sensor units can be specified based on the installation interval of each transmission path 102 and the transmission path length obtained for each sensor unit.

  Thus, when the transmission path 102 is installed linearly, each sensor unit 101 fixed along the transmission path 102 may return a response signal including only ID information. In other words, in each sensor unit 101, functions related to setting and sending of angle information can be omitted.

  In addition, when installing the transmission path 102 to which the sensor unit 101 is fixed, for example, a method of burying the transmission path 102 along a straw provided in a farm field can be employed. In such a case, after embedding the transmission path 102 and the sensor unit 101, the distance between the transmission paths 102 can be obtained by measuring the distance between the ridges.

  Therefore, even in a multipoint measurement system having a configuration in which a plurality of transmission lines 102 are converged and used as shown in FIG. 10, complicated operations such as position registration are not required when installing each sensor unit 101. is there.

By the way, instead of calculating the transmission path length between the multipoint measurement data acquisition device 110 and each sensor unit 101 based on the response time from each sensor unit 101, information indicating the transmission path length from each sensor unit 101. It is also possible to return a response signal including
(Another embodiment of sensor unit)
FIG. 11 shows another embodiment of the sensor unit. 11 that are the same as those shown in FIG. 3 are given the same reference numerals, and descriptions thereof are omitted.

  For example, a length mark 104 indicating the length from one end of the transmission path 102 is attached to the transmission path 102 illustrated in FIG. 11 at a predetermined interval. Further, a bending angle mark 104 indicating a bending direction of the transmission path is attached to a portion where the sensor unit 101 of the transmission path 102 of FIG. 11 is fixed.

  The sensor unit 101 shown in FIG. 11 has an optical sensor 241. The optical sensor 241 includes a length mark reading unit 242 and a bending angle mark reading unit 243. Then, the reading result by the length mark reading unit 242 is held in the transmission path length holding unit 244 that is also received by the memory 226. Further, the angle information indicated by the reading result by the bending angle mark reading unit 243 is held in the angle information holding unit 228.

  FIG. 12 is a diagram illustrating another embodiment of the sensor unit. Note that among the constituent elements shown in FIG. 12, the same constituent elements as those shown in FIG. 3 and FIG. 11 are denoted by the same reference numerals, and description thereof is omitted.

  FIG. 12A shows an arrangement example of the optical sensor 241 and the transmission path 102 included in the sensor unit 101. 12B and 12C show examples of arrangement of the length mark 104 and the bending angle mark 105. FIG.

  In the example shown in FIG. 12A, the optical sensor 241 is arranged corresponding to the groove 231 provided in the left-right direction in the paper surface in the case in which the control circuit unit 230 of the sensor unit 101 is housed. For example, by providing a window formed of a transparent member or the like in a part of the groove 231 described above, the length mark 104 and the bending angle mark 105 can be read by the optical sensor 241 in the case.

  In the example of the length mark 104 shown in FIG. 12B, a numerical value representing the length from one end of the transmission path 102 is, for example, at intervals of 0.1 m, and the coaxial cable used as the transmission path 102 is covered. It is printed on a film. In the example shown in FIG. 12B, a numerical value indicating the length is printed a plurality of times in the circumferential direction of the coaxial cable. When such a length mark 104 is applied, the length mark reading unit 242 shown in FIG. 11 can read some numbers printed on the film of the transmission path 102 through the window described above. it can. Then, the length mark reading unit 242 generates transmission path length data indicating the transmission path length corresponding to the reading result. The transmission path length data is held in the transmission path length holding unit 244.

  In the example of the length mark 104 shown in FIG. 12C, a barcode indicating the length from one end of the transmission path 102 is printed on a coating film of a coaxial cable used as the transmission path 102. Each bar included in the barcode can be printed so as to make a round in the circumferential direction of the coaxial cable. When such a length mark 104 is applied, the length mark reading unit 242 illustrated in FIG. 11 can read the barcode printed on the film of the transmission path 102 through the window described above. Then, the length mark reading unit 242 generates transmission path length data representing the transmission path length corresponding to the read barcode. The transmission path length data is held in the transmission path length holding unit 244.

  In the multipoint measurement system using the transmission line 102 having such a length mark 104, each sensor unit 101 is fixed in an arrangement in which the length mark 104 can be read by the optical sensor 241. Therefore, in such a multipoint measurement system, the accuracy of the transmission path length corresponding to each sensor unit 101 by the multipoint measurement data acquisition device 110 is the printing position when the length mark 104 is printed on the film of the coaxial cable. The accuracy is equivalent to the accuracy of.

  In the example of the bending angle mark 105 shown in FIGS. 12B and 12C, a color tape representing the bending angle of the transmission path 102 is wound around a coating film of a coaxial cable used as the transmission path 102. It is. The color of the tape corresponding to the bending angle can be determined in advance, for example, every 90 degrees. Further, when the transmission path 102 is not bent at the position of the sensor unit 101, the addition of the bending angle mark 105 can be omitted.

  When such a bend angle mark 105 is used, the bend angle mark reading unit 243 included in the sensor unit 101 identifies the color of the tape attached as the bend angle mark 105. Then, angle information corresponding to the identified color is generated by the bending angle mark reading unit 243. As in the example of the sensor unit 101 shown in FIG. 11, the configuration in which the bending mark 105 is read by the bending mark reading unit 243 is another example of the direction information generation unit. The angle information generated by the bending angle mark reading unit 243 is held in the angle information holding unit 228. When the bend angle mark 105 is omitted, the bend angle mark reading unit 243 generates angle information indicating that the bend angle is 180 degrees based on the read result corresponding to the color of the coating of the coaxial cable. can do. The angle information generated in this way is held in the angle information holding unit 228.

  When the microcontroller 225 included in the sensor unit 101 shown in FIG. 11 receives a request signal including the ID of its own device from the multipoint measurement data acquisition apparatus 110, the microcontroller 225 generates a response signal including transmission path length data together with angle information. Generate. At this time, the microcontroller 225 determines whether or not the angle information indicates that the bending angle is 180 degrees, and if the determination is affirmative, the angle information can be omitted.

  Moreover, according to the response signal from the sensor unit 101 as shown in FIG. 11, the microcontroller 201 of the multipoint measurement data acquisition apparatus 110 can collect the arrangement information as described below.

  FIG. 13 is a flowchart showing another embodiment of the position information collecting operation. Note that among the constituent elements shown in FIG. 13, those equivalent to the constituent elements shown in FIG. 4 are denoted by the same reference numerals, and description thereof is omitted.

  In the flowchart shown in FIG. 13, step 331 is executed at the time of affirmative determination in step 303 instead of steps 302 and 304 shown in FIG. In step 331, the microcontroller 201 detects transmission path length data indicating the transmission path length L from the response signal.

  Next, the microcontroller 201 determines whether or not angle information is included in the response signal (step 332). When the angle information cannot be detected from the response signal (No determination at step 332), the microcontroller 201 generates angle information indicating that the bending angle A corresponding to the sensor unit 101 indicated by the ID is 180 degrees. (Step 333).

  After the end of step 333 and in the case of an affirmative determination in step 332 described above, the process proceeds to step 305. In step 305, the transmission path length and angle information obtained as described above are held in the memory 202 by the microcontroller 201.

  It should be noted that the length mark 104 as illustrated in FIGS. 12B and 12C and a mechanism for obtaining angle information using a switch provided in the groove 231 illustrated in FIG. 8 are applied in combination. You can also

  On the other hand, the arrangement position of the plurality of sensor units 101 on the transmission path can be limited to a position indicated by a multiple of a predetermined length D from one end of the transmission path 102.

  FIG. 14 shows another embodiment of the multipoint measurement system. Of the components shown in FIG. 14, components equivalent to those shown in FIG. 1 are denoted by the same reference numerals and description thereof is omitted. Further, in FIG. 14, each sensor unit 101 is indicated by white circles with reference numerals S <b> 1 to S <b> 9 that are combinations of the order numbers close to the multipoint measurement data acquisition device 110 and the reference numerals S.

  For example, an installation position mark can be attached to the transmission path 102 for each predetermined length D from one end connected to the multipoint measurement data acquisition device 110. In addition, this predetermined length D can be determined based on the space | interval of the cocoon provided in the agricultural field, etc. When the sensor unit 101 is installed, for example, the sensor unit 101 can be fixed to the transmission path 102 so that any one of the installation position marks coincides with the center of the case of the sensor unit 101.

  In this way, the transmission path length to each sensor unit 101 can be limited to a multiple of the predetermined length D described above. When such a limitation holds, the transmission path length corresponding to each sensor unit 101 can be specified with high accuracy even when the measurement accuracy of response time is limited. That is, based on the measurement result of the response time, it is possible to acquire position information with the same accuracy as when the optical sensor 241 for reading the length mark 104 is provided.

Regarding the above description, the following items are further disclosed.
(Appendix 1)
The transmission path length from the position where each of the sensor units is fixed to one end of the transmission path and the respective sensors from the responses returned through the transmission path by each of the plurality of sensor units fixed to one transmission path An information extraction unit for extracting information including information on the bending direction of the transmission path at a fixed position of the unit;
A multipoint measurement data acquisition apparatus comprising: an arrangement estimation unit that estimates the arrangement of the plurality of sensor units based on the information extracted by the information extraction unit.
(Appendix 2)
In the multipoint measurement data acquisition device according to attachment 1,
The information extraction unit includes:
A signal detection unit that detects a leakage signal when transmitting a signal of a predetermined frequency via the transmission path embedded in the ground together with each sensor unit;
The signal having the predetermined frequency is attenuated by propagation of a distance shorter than the shortest distance between the plurality of sensor units and the multipoint measurement data acquisition device when the signal leaks into the ground where the transmission path is embedded. A multipoint measurement data acquisition apparatus characterized by comprising:
(Appendix 3)
In the multipoint measurement data acquisition device according to Supplementary Note 1 or Supplementary Note 2,
The information extraction unit includes:
A request sending unit for sending a request signal for requesting the response to each sensor unit via the transmission line;
A transmission path length calculation unit that calculates the transmission path length to the destination sensor unit based on the time from when the request signal is sent to when the response is returned from the sensor unit that is the destination of the request signal A multipoint measurement data acquisition apparatus characterized by comprising:
(Appendix 4)
In the multipoint measurement data acquisition device according to any one of Supplementary Notes 1 to 3,
The information extraction unit exits the direction of the transmission path to the sensor unit and the sensor unit when information on the bending direction of the transmission path is omitted in the response returned from one of the plurality of sensor units. A multipoint measurement data acquisition apparatus characterized in that information indicating that the direction of the transmission line is the same is extracted.
(Appendix 5)
In the multipoint measurement data acquisition device according to any one of Supplementary Notes 1 to 4,
The arrangement estimation unit
A rearrangement unit that rearranges information regarding the bending direction of the transmission path at the position where each sensor unit is arranged and identification information of each sensor unit in ascending order of transmission path length from each sensor unit to one end of the transmission path. When,
The difference between the transmission path length D _{j + 1} corresponding to the transmission path length D _j and j + 1-th sensor unit corresponding to the j-th sensor unit according to the order determined by the sorting unit length Satoshi, from the j-th sensor unit A vector addition unit that calculates the position of the j + 1th sensor unit by adding a vector having a direction indicated by the information regarding the bending direction included in the response to the position of the jth sensor unit. A multipoint measurement data acquisition device that is characterized.
(Appendix 6)
In the multipoint measurement data acquisition device according to any one of Supplementary Notes 1 to 5,
The information regarding the bending direction of the transmission path included in the response returned from each sensor unit is information indicating the height of the installation position of each sensor unit with reference to the height of another sensor unit set adjacently. A multipoint measurement data acquisition device characterized by comprising:
(Appendix 7)
A plurality of sensor units fixed to one transmission line;
From the response returned by each of the plurality of sensor units via the transmission path, the position where each sensor unit is fixed, the transmission path length to one end of the transmission path, and the transmission path at the fixed position of each sensor unit An information extraction unit for extracting information including information on the bending direction of
A multipoint measurement system, comprising: an arrangement estimation unit that estimates the arrangement of the plurality of sensor units based on information extracted by the information extraction unit.
(Appendix 8)
In the multipoint measurement system described in appendix 7,
The plurality of sensor units are:
A transmission path holding unit that holds the transmission path so as to fix the direction in which the transmission path reaches the sensor unit and the direction from the sensor unit;
A direction information generating unit that generates information indicating a bending direction of the transmission path at the position of the sensor unit based on information indicating a direction in which the transmission path is held by the transmission path holding unit. Multipoint measurement system.
(Appendix 9)
In the multipoint measurement system described in appendix 7,
The plurality of sensor units are fixed at positions where the length from one end of the transmission path is an integral multiple of a predetermined length.
(Appendix 10)
Collecting responses returned through the transmission line by each of a plurality of sensor units fixed to one transmission line;
From the collected responses, information including a transmission path length from a position where each sensor unit is fixed to one end of the transmission path and information regarding a bending direction of the transmission path at the fixed position of each sensor unit is extracted. ,
A multipoint measurement data acquisition method characterized by estimating a position at which measurement data is acquired by each of the plurality of sensor units based on the extracted information.

DESCRIPTION OF SYMBOLS 101 ... Sensor unit; 102 ... Transmission path; 103, 235 ... Switch; 104 ... Length mark; 105 ... Bending-angle mark; 110 ... Multipoint measurement data acquisition apparatus; 111 ... Information extraction part; , 210 ... transmission / reception unit; 114 ... request transmission unit; 115 ... response detection unit; 116 ... transmission path length calculation unit; 117 ... measurement data collection unit; 118 ... arrangement information holding unit; 119 ... rearrangement unit; 201, 225 ... Microcontroller; 202, 226 ... Memory; 211 ... Modulator; 212, 215 ... Amplifier; 213 ... Transmitting antenna; 214 ... Receiving antenna; 216 ... Demodulator; 221 ... Temperature sensor; 223 ... Temperature measurement unit; 224 ... Soil moisture measurement unit; 227 ... ID holding unit; 228 ... Angle information holding unit; 230 ... Control 231 ... groove; 232 ... transmission path holding unit; 233 ... cover; 234 ... transmission / reception antenna; 236 ... direction information generation unit; 241 ... optical sensor; 242 ... length mark reading unit; Part; 244 ... Transmission path length holding part

Claims (6)

From the response returned through the transmission path by each of a plurality of sensor units fixed to one transmission path, the position where each sensor unit is fixed, the transmission path length to one end of the transmission path, and each sensor An information extraction unit for extracting information including information on the bending direction of the transmission path at a fixed position of the unit;
A multipoint measurement data acquisition apparatus comprising: an arrangement estimation unit that estimates the arrangement of the plurality of sensor units based on information extracted by the information extraction unit. In the multipoint measurement data acquisition device according to claim 1,
The information extraction unit includes:
A request sending unit for sending a request signal for requesting the response to each sensor unit via the transmission line;
A transmission path length calculation unit that calculates a transmission path length to the destination sensor unit based on a time from when the request signal is transmitted until the response is returned from the sensor unit that is the destination of the request signal; A multi-point measurement data acquisition device characterized by comprising: In the multipoint measurement data acquisition device according to claim 1 or 2,
The arrangement estimation unit
A rearrangement unit that rearranges information regarding the bending direction of the transmission path at the position where each sensor unit is arranged and identification information of each sensor unit in ascending order of transmission path length from each sensor unit to one end of the transmission path. When,
The difference between the transmission path length D _{j + 1} corresponding to the transmission path length D _j and j + 1-th sensor unit corresponding to the j-th sensor unit according to the order determined by the sorting unit length Satoshi, from the j-th sensor unit A vector adding unit that calculates the position of the j + 1th sensor unit by adding a vector having a direction indicated by the information regarding the bending direction included in the response to the position of the jth sensor unit. Multipoint measurement data acquisition device characterized by A plurality of sensor units fixed to one transmission line;
From the response returned by each of the plurality of sensor units via the transmission path, the position where each sensor unit is fixed, the transmission path length to one end of the transmission path, and the transmission path at the fixed position of each sensor unit An information extraction unit for extracting information including information on the bending direction of
A multipoint measurement system, comprising: an arrangement estimation unit that estimates the arrangement of the plurality of sensor units based on information extracted by the information extraction unit. The multipoint measurement system according to claim 4,
The plurality of sensor units are:
A transmission path holding unit that holds the transmission path so as to fix the direction in which the transmission path reaches the sensor unit and the direction from the sensor unit;
A direction information generating unit configured to generate information indicating a bending direction of the transmission path at the position of the sensor unit based on information indicating a direction in which the transmission path is held by the transmission path holding unit. Multipoint measurement system. Collecting responses returned through the transmission line by each of a plurality of sensor units fixed to one transmission line;
From the collected responses, information including a position where each sensor unit is fixed, a transmission path length to one end of the transmission path, and information regarding a bending direction of the transmission path at the fixed position of each sensor unit is extracted. ,
A multipoint measurement data acquisition method characterized by estimating a position at which measurement data is acquired by each of the plurality of sensor units based on the extracted information.

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