KR100798406B1 - A System for Measuring Flow Velocity using Real Time Locating System and a Measuring Float used in the Said System - Google Patents

Abstract

The present invention relates to a flow rate measuring system using a real-time position measuring system and the rich for measurement used therein. More specifically, real-time position measurement is possible without the influence of dry season or flooding, and can be measured automatically without measuring personnel, and it is possible to measure the flow rate in real time regardless of the weather, light quantity, visible distance, water level, and flow rate. The present invention relates to a flow rate measurement system using the system, and a measurement rich used therein.

Flow rate measurement system using a real-time position measurement system capable of measuring the flow rate of the present invention and the measurement rich used therein, is attached to the rich to be injected into the river, wireless LAN communication (WiFi) or low frequency radio wave identification communication ( A plurality of tags that transmit signals periodically using RF) and are individually distinguishable by unique numbers assigned to hardware; A plurality of position receivers fixedly disposed and arranged along the river, and receiving a signal transmitted from the tag; A gateway for integrating and collecting signals of the tags received from the location receivers; Receives the signals of the collected tags from the gateway and performs calculation based on the signals of the tags transmitted from the gateway and a previously input topographic map to calculate stream physical location information of a specific location and a specific time of the river in real time. Management computer; A database server for storing river physical quantity information according to geography and time calculated by the management computer; And a web server for accessing the database server to transmit stream physical quantity information according to the geography and time stored over the Internet. It is preferable to further include. In addition, it is preferable that the rich person is further equipped with a sensor for further measuring physical quantity information of the river in addition to the tag.

River, River, Downstream, Flow, Flow Rate, Water Level, Sensor, Tag, RTLS, RF, RFID, GIS, Rich, Float, TDOA

Description

{A System for Measuring Flow Velocity using Real Time Locating System and a Measuring Float used in the Said System}

1 is a system configuration diagram of a flow rate measuring system according to the present invention.

2 is an installation and operation of the flow rate measuring system according to the present invention.

3 is an explanatory diagram of a TDOA method used in the present invention.

4 is another explanatory diagram of a TDOA method used in the present invention.

5 is a cross-sectional view of the measurement rich (rod form) according to the present invention.

6 is a cross-sectional view of the measurement rich (planar form) according to the present invention.

** Description of the symbols for the main parts of the drawings **

100: flow rate measuring system according to the present invention

101: Tag 102: Position Receiver

103: gateway 104: management computer

105: database server 106: web server

107: terminal

102a, 102b, 102c: Position receivers 1, 2, 3

200: rich for measurement (stick type)

201a: tag 201b: sensor

202: waterproof cover

210: main body 211: sealing cap

212: sand 213: internal stopper

300: rich for measurement (flat form)

301a: tag 301b: sensor

310: main body 311: float

The present invention relates to a flow rate measuring system using a real-time position measuring system and the rich for measurement used therein. More specifically, real-time position measurement is possible without the influence of dry season or flooding, and can be measured automatically without measuring personnel, and it is possible to measure the flow rate in real time regardless of the weather, light quantity, visible distance, water level, and flow rate. The present invention relates to a flow rate measurement system using the system, and to the measurement rich used therein.

It is well known that in the past, a large portion of the measurement has been relied on by the measurement personnel. Conventional flow rate measurement methods can be classified into three types, three of which are a method of using a flow meter, a method of using rich parts, and a method of using an electromagnetic wave surface flow meter. The use of a tachometer is effective in dry seasons and areas with low or low water velocities, and the use of the rich is used in floods, high speed and deep water areas, and electromagnetic surface tachometers are more accurate than the two methods. In addition to obtaining flow rate and flow rate information, there is an advantage in that the flow rate can be measured without direct contact with water. Specifically, each method will be described.In the method of using the tachometer, the appropriate measuring point is selected in consideration of various effects, and the measuring personnel input the tachometer to the selected measuring point to measure the flow rate. Alternatively, after selecting two or more observation lines and establishing a communication system between the measurement personnel, the flow rate of the rich man who passed through each observation line was measured using the observers' visual and stopwatches. In addition, the electromagnetic wave surface velocity meter is installed in the transverse direction of the river, and measures the flow rate by receiving a reflected wave by launching a radio wave of a constant frequency on the water surface.

As can be seen from the description of each of the above methods, the use of a tachometer or a rich mandate shows that there are absolutely a large number of trained measuring personnel. For example, when measuring flow rates, the risk of safety accidents to measurement personnel increases. In addition, since the measurement of the flow rate using the tachometer can only be measured at the single point at which the tachometer is located, in order to find the average flow velocity of the entire stream, it is necessary to measure at several points and calculate the average flow rate from this data. The flow rate measurement using the two methods requires a large number of manpower, considering that the observation of the rich is made by the observer's neck and the measurement of the time is made by the measurement personnel operating the stopwatch. And the possibility of getting inaccurate data cannot be ruled out. When using an electromagnetic surface flowmeter, more accurate data can be obtained.However, it is possible to measure only when the river has a flow velocity higher than a certain speed (currently 0.5m / s). It has a disadvantage. In addition, all of the above methods have a problem in that it is impossible to measure the flow velocity of a river that changes every time.

In addition, when the flow rate is measured by the above methods, only the flow rate and flow rate information of the stream can be obtained. Therefore, the concentration of water temperature, water pressure, turbidity, and certain substances (for example, oxygen and pollutants) can be determined. In order to obtain a new measurement task, a duplicate task is not only duplicated, but also the risks of the task are repeated.

Many of these inconveniences are due to the limitations of the equipment and the measurement method itself, and therefore, in order to solve such inconveniences, improvements in flow rate measuring equipment and systems are highly required.

Accordingly, the present invention has been made to solve the problems of the prior art as described above, the object of the present invention is to secure a real-time, small number of people automatically or automatically, regardless of the dry season or flooding period, depth of depth, speed of the flow rate, etc. The present invention provides a flow rate measuring system capable of measuring flow rate and other river information, and a measurement rich part used therein.

Flow rate measurement system using a real-time position measurement system that can measure the real-time flow rate of the present invention for achieving the above object, and the measurement rich used therein, is attached to the rich to be injected into the river, wireless LAN communication A plurality of tags that transmit signals periodically using Wi-Fi or low frequency radio frequency identification (RF), and which are individually distinguishable by unique numbers assigned to hardware; A plurality of position receivers fixedly disposed and arranged along the river, and receiving a signal transmitted from the tag; A gateway for integrating and collecting signals of the tags received from the location receivers; Receives the signals of the collected tags from the gateway and performs calculation based on the signals of the tags transmitted from the gateway and a previously input topographic map to calculate stream physical location information of a specific location and a specific time of the river in real time. Management computer; A database server for storing river physical quantity information according to geography and time calculated by the management computer; And a web server for accessing the database server to transmit stream physical quantity information according to the geography and time stored over the Internet. It is preferable to further include. In addition, it is preferable that the rich person is further equipped with a sensor for further measuring physical quantity information of the river in addition to the tag.

The stream physical quantity information includes a flow rate and further includes at least one of water level, water temperature, water pressure, quantity, turbidity, and concentration of a specific substance. The location receiver receives a signal transmitted by the tag through a wireless LAN communication (WiFi) in a high frequency band and serves as a low frequency RFID reader function in a low frequency band to receive a signal transmitted by the tag. The operation performed by the management computer may be performed by obtaining a location information according to time of the tag using a time difference of area (TDOA) method and calculating flow velocity information based on the obtained location information according to time of the tag. It is characterized by. In addition, it is preferable that the management computer selectively use any one of wired communication, wireless LAN (WiFi) communication or CDMA communication as a means for receiving the signals of the tags collected by the gateway. As a means for supplying power, PoE (Power of Ethernet) may be used, or an electric line, a solar cell, a battery, or a charger may be selectively used.

In addition, the measurement rich according to the present invention periodically transmits a signal using a wireless LAN communication (WiFi) or low frequency radio frequency identification (RF), and the tag is individually distinguishable by a unique number assigned to the hardware In addition, the floating float is characterized in that the rectangle, and the sensor for measuring the physical quantity information of the river is more preferably mounted in addition to the tag. In addition, it is preferable to further include a program for controlling the period for transmitting the signal and a memory for storing the contents of the signal to be transmitted, the period in which the signal is transmitted may be differently programmed according to the user's purpose do.

Hereinafter, the flow rate measuring system using the real-time position measuring system according to the present invention having the configuration as described above and the measurement rich used for this will be described in detail with reference to the accompanying drawings.

Figure 1 schematically shows the configuration of the flow rate measurement system using a real-time position measurement system according to the present invention. The tag 101 attached to the rich is put into the stream and flows along the stream, and sends a signal to the surroundings. As shown in FIG. 1 to inform its location, wireless communication (WiFi) is performed in the high frequency band (for long distance transmission). Signal) and a low frequency radio frequency identification communication (RF) signal in the low frequency band (for near field transmission). At this time, the tag 101 is not only its own position, but also the water level, water temperature, water pressure, quantity, turbidity, and a specific substance (for example, oxygen) measured at the position measured by a sensor (not shown in FIG. 1) which is further attached to the rich man. • A signal containing information on the physical quantity of the river, such as the concentration of pollutants, etc., can be transmitted together.

The position receiver 102 receives a signal transmitted from this tag. The location receiver 102 is provided with a receiver capable of receiving a wireless LAN communication (WiFi) signal, and also has a low frequency RFID reader function so that a low frequency RFID tag within a predetermined range is provided. Activate to activate the signal. (I.e., it is possible to receive a wireless LAN communication (WiFi) signal in the high frequency band, and a low frequency radio frequency identification communication (RF) signal in the low frequency band.) Signals of the tags 101 received by each position receiver 102 They are collected by being integrated into the gateway 103. At this time, information is provided between the location receiver 102 and the gateway 103 by communication means for both short-range and long-distance such as a wired LAN, a wireless LAN, and CDMA. It is desirable that there is no omission of. The signals collected by the gateway 103 are sent to the management computer 104 for analysis, and the position information of the tag 101 is calculated through a predetermined operation. The location information of the tag 101 calculated by the management computer 104 makes it possible to calculate the speed information of the tag 101, that is, the flow velocity information of the stream, and at the same time the physical quantity of the stream received from the tag 101. Information is also collected and recorded with the calculated position information. Through the above process, the physical quantity information of the flow rate and the river is calculated according to each geography and time by the management computer 104, and can be displayed on the management computer 104 in real time.

The geographic and time-specific flow velocity and stream physical quantity information calculated and recorded according to the location information of the tag 101 are displayed on the management computer 104 as well as stored in the database server 105 connected thereto. Further, the web server 106 is further provided so that the information stored in the database server 105 can be read and accessed by the terminal 107 such as another computer, laptop or mobile phone through the Internet. desirable.

Conventionally, only the low frequency radio frequency communication (RF) is used, and the recognition range is only about 5 to 10 m, and only the tag can be determined whether or not the tag is included in the range. In addition, location tracking requires separate positioning hardware such as GPS or INS, and many kinds of location tracking methods are missing depending on the terrain or river conditions (such as high wave amplitude or high velocity). Difficulties followed, but the method proposed by this method not only solves all of the above problems, but also saves the cost of configuring the system because expensive GPS or INS equipment as described above is not required. Economic benefits also have advantages.

Figure 2 shows the actual installation and operation of the flow rate measurement system using a real-time position measurement system according to the present invention. As shown, a plurality of tags 101 attached to the rich drop into the stream so that the tags 101 flow down as the stream flows, and the plurality of position receivers 102 are connected to the tags 101. It is pre-installed around the river to receive the signal transmitted from. The location receivers 102 selectively determine the interval, location, and power supply method installed according to the location receiver 102's own performance, signal transmission performance of the tag 101, and external factors according to the surrounding environment such as terrain and flow velocity. In particular, it is recommended to thoroughly waterproof the equipment so that it can be operated stably without malfunctioning due to water intrusion. If the location receiver 102 is close to the gateway 103, using the wireless LAN communication (WiFi) is the easiest way to build a system, but the distance is within the range that can use the wireless LAN communication (WiFi) (currently approximately 200m) In case of exceeding the above, it is desirable to have a performance such as CDMA communication so that there is no loss of data. In addition, in the case of fixed installation of power supply, power construction or solar cell may be used. However, considering the fact that the installation cost for power supply is high, the construction cost is increased. For this reason, it is desirable to use a charger or a battery when the construction is difficult or in a temporary measurement area. In addition, in the case where power is supplied to the location receiver 102 by wire, as in the case where it is fixedly installed, a power source employing a PoE (Power of Ethernet) technology that can simultaneously supply information and power to the location receiver 102. The supply method may be used.

The TDOA method and the Radio Signal Strength Indicator / Received Signal Strength Indication (RSSI) method are typically used as a location measuring method in modern times. The RSSI method is a simple method because it measures only the strength (quantity) of all received signals coming into the terminal. Although it can be easily implemented, errors may occur in the distance measurement due to reflection / interference effects and shadow effects on a plurality of signals, and in particular, since reliability is inferior in a nonlinear propagation environment, the present invention Introduced TDOA method with better position reliability.

3 and 4 illustrate a time difference of area (TDOA) method, which is a basic principle of the position measuring method used in the present invention as described above.

3 illustrates a process of obtaining a time difference according to the position of the tag 101. As shown in Fig. 3A, the position of the tag 101 is received by receiving the signal of the tag 101 from the three position receivers 102a, 102b and 102c (hereinafter referred to as 102 * in the integrated expression). The outgoing signal transmitted from the tag 101, the delayed tag signal, and the received signal (received signal 1, received signal 2, received signal 3) at each position receiver are measured as shown in FIG. appear. Unlike the time of area (TOA) method, the TDOA method is not intended to estimate an absolute time at which a signal is received, but is to estimate a time difference between signals received at each position receiver 102 *. For this reason, it is not necessary to accurately determine the time at which the signal was first transmitted from the tag 101, the delayed time, or the like. Therefore, the time difference T _1, T _2, T ₃ from the arbitrarily set reference time T ₀ until a specific pulse is received at each position receiver 1 102a, position receiver 2 102b, and position receiver 3 102c. The location estimation is performed based on the time difference information collected at the gateway or management computer. To calculate the time difference based on this basic principle, in practice, the following correlation method is generally used. Signals and noises transmitted from the tag 101 are the strengths of radio waves over time, and can be viewed as functions having time as an independent variable. Therefore, we can think of the following equation.

In the above formula, i and j are subscripts assigned to distinguish each location receiver, x (t) is a signal received from the location receiver, s (t) is a signal transmitted from the tag, and n (t) is noise ( Noise), Δt means the time interval delayed from the time transmitted from the tag to the time received by the position receiver. Correlation these two signals for a sufficiently long time using the following equation, and find the value of τ when the cross-correlation value ( R _xixj ) becomes the maximum. This is the desired TDOA, that is, the time difference value. .

The TDOA method as described above has been studied and published by various literatures, and is a widely used principle. There are a number of positioning algorithms using the TDOA method and a number of solutions proposed by various scholars. In this regard, only the above brief description will be given. However, in the TDOA method, there are various existing algorithms and solutions proposed by Smith & Abel, but the method proposed by Chan & Ho is based on the empirical results introduced into the real environment. Since it is known to show the optimum performance in the position determination using the base station, it is preferable to use the TDOA method according to the method proposed by Chan & Ho described above in the present invention.

4 shows an algorithm principle of finding the position of the actual tag 101 by using the time difference obtained by the above method. When the signal is transmitted from the tag 101, the signal of the tag 101 is received at each position receiver 102 *, but is not simultaneously received at the time when the tag 101 is transmitted. The signal is received with a time delay depending on the distance the receiver 102 * is away. With respect to the two position receivers 102 *, the difference in the time at which the signal of the tag 101 is received is directly proportional to the difference in the distance between the tag 101 and the respective position receivers 102 *. Thus, it can be seen that the tag 101 is theoretically somewhere on a hyperbola with the two position receivers 102 * in focus. In this manner, the trajectories of the hyperbolic curves can be obtained for the two position receivers 102 *. Similarly, the trajectories of the other hyperbolic curves can be obtained by selecting two other position receivers 102 *. In Fig. 4, a hyperbolic A focusing on the position receiver 1 102a and the position receiver 2 102b, and a hyperbola B focusing on the position receiver 2 102b and the position receiver 3 102c are shown. Since the tag 101 must exist on the trajectory indicated by the hyperbolic A and the hyperbolic B, the position satisfying all the conditions is the intersection position where the hyperbolic A and the hyperbolic B meet as shown in FIG. In the same manner, a unique solution regarding the position of the tag 101 can be obtained.

5 and 6 are schematic views showing the configuration of the measurement rich (200, 300) used in the flow rate measurement system using a real-time position measurement system proposed in the present invention, Figure 5 is a cross-sectional view of the rod-shaped rich, Figure 6 Is a perspective view of a rich man in flat form.

The configuration of the rod-shaped rich body 200 will be described with reference to FIG. 5. First, the upper and lower ends of the long pipe-shaped main body 210 are sealed by a sealing cap 211. A heavy material such as sand 212 is accommodated in the main body 210 and the inner plug 213 is used. As the sand 212 is fixed, an empty space remains on the upper portion of the main body 210 so that the center of gravity of the entire measurement rich man 200 can be concentrated on the lower end portion. As described above, the center of gravity is concentrated on the lower end portion, so that the measurement rich 200 is kept in a vertical position with respect to the surface of the water when it is introduced into the river and floats. The tag 201a and the sensor 201b are attached to an upper portion of the sealing cap 211 on the side where the empty space exists, and the physical quantity information of the river (water level, water temperature, water pressure, quantity, turbidity, and a specific substance) by the sensor 201b. Concentration, etc.), and a signal including the physical quantity information is transmitted by the tag 201a. The tag 201a is preferably protected by the waterproof cover 202 so that the tag 201a may not be malfunctioned due to an external shock or immersion.

The flat rich man 300 shown in FIG. 6 has substantially the same configuration as the rod rich man 200 described above, but the float 311 is further positioned at the upper sealing cap 211 in the rod rich man 200. The difference is provided. The float 311 is made of a material that can float on water, such as styrofoam, and is formed in a wide flat shape, and is accommodated at the bottom of the body 210 in the rod-shaped rich body 200 to concentrate the center of gravity at the bottom. Functions similar to the sand 212 (notice that the planar rich man 300 is provided with all the inner cap, sand, and sealing cap), that is, the position of the rich body 310 in water is constant Function to keep it intact. Of course, the float 311 may be any shape such as a circle or an ellipse, not necessarily a quadrangular shape as shown in FIG. 6, as long as it is a flat shape for satisfying the above-described purpose. 6 is a conceptual perspective view of the rich for measurement according to the present invention, but the tag 301a and the sensor 301b are arranged side by side, but the tag 301a is waterproof as described in the description of the rod-shaped rich 200. It is preferable to further provide a structure such as a cover, and the sensor 301b may be attached to a lower portion of the float 311 or a predetermined position on the main body 310 so as to better measure the state of the river.

The present invention is not limited to the above-described embodiments, and the scope of application is not limited to those of ordinary skill in the art to which the present invention pertains without departing from the gist of the present invention as claimed in the claims. Of course, various modifications are possible.

As described above, according to the present invention, there is an effect that the flow velocity can be measured irrespective of the timing such as the dry season / flood season, the depth of the depth, the speed of the velocity, the topography or the depth of the measurement region, and the like. In addition, it is possible to measure the flow rate information and at the same time, other river information (water level, water temperature, water pressure, quantity, turbidity, concentration of specific substances, etc.) at the same time, as well as measuring the information accurately and in real time. It is possible to do In addition, according to the present invention is not economical because a lot of manpower and additional facilities are required for the measurement, it is economical, there is an effect that can ensure the safety of the measurement personnel because the measurement is made automatically.

Claims (13)

It is equipped with a sensor for measuring river physical quantity information including a flow rate, and further including at least one or more of water level, water temperature, water pressure, quantity, turbidity, and concentration of a specific substance, and is attached to the rich man put into the river, and wireless LAN communication. A plurality of tags that transmit signals periodically using Wi-Fi or low frequency radio frequency identification (RF), and which are individually distinguishable by unique numbers assigned to hardware; A plurality of position receivers fixedly disposed and arranged along the river, and receiving a signal transmitted from the tag; A gateway for integrating and collecting signals of the tags received from the location receivers; Receives the signals of the collected tags from the gateway and performs calculation based on the signals of the tags transmitted from the gateway and a previously input topographic map to calculate stream physical location information of a specific location and a specific time of the river in real time. Management computer; A database server for storing river physical quantity information according to geography and time calculated by the management computer; A web server accessing the database server and transmitting stream physical quantity information according to the geography and time stored through the Internet; Flow rate measurement system using a real-time position measurement system, characterized in that made. delete delete delete The method of claim 1, The location receiver receives a signal transmitted by the tag through a wireless LAN communication (WiFi) in a high frequency band and serves as a low frequency RFID reader function in a low frequency band to receive a signal transmitted by the tag. Flow rate measurement system using a real-time position measurement system, characterized in that. The method of claim 5, The operation performed by the management computer may include obtaining location information according to time of the tag by using a time difference of area (TDOA) method, and calculating flow velocity information based on the obtained location information according to time of the tag. Velocity measurement system using real-time position measurement system. The method of claim 6, The management computer selectively uses any one of wired communication, wireless LAN (WiFi) communication, or CDMA communication as a means for receiving the signals of the tags collected by the gateway. Flow measurement system. The method of claim 7, wherein And a PoE (Power of Ethernet) as a means for supplying power to the position receiver. The method of claim 7, wherein And at least one of an electric line, a solar cell, a battery, and a charger as a means for supplying power to the position receiver. A sensor is used to periodically transmit a signal by using a wireless LAN communication (WiFi) or a low frequency radio wave identification communication (RF), and to measure a tag and river physical quantity information that can be individually discriminated by a unique number assigned to hardware. The rich for measurement, characterized in that the float floats in water. delete The method of claim 10, And a program for controlling the period at which the signal is transmitted and a memory for storing contents of the signal to be transmitted. The method of claim 12, The period in which the signal is transmitted may be differently programmed according to the purpose of the user.

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