WO2012104230A1

WO2012104230A1 - Device and method for ascertaining measurement values in a flowing medium

Info

Publication number: WO2012104230A1
Application number: PCT/EP2012/051393
Authority: WO
Inventors: Daniel Evers; Christoph Weiler
Original assignee: Siemens Aktiengesellschaft
Priority date: 2011-02-01
Filing date: 2012-01-30
Publication date: 2012-08-09
Also published as: DE102011003438B4; DE102011003438A1

Abstract

The invention relates to the ascertainment of measurement values in a fluid (2), in particular in a liquid medium, flowing through a channel system (1), and to the transmission of the ascertained measurement values to an evaluation device. A plurality of RFID readers (60) are arranged on the channel system. RFID probes (50) which float in the medium and are carried away by the flow current are used for recording measurement values. The probes have a sensor unit (51) for recording measurement values and an RFID component (54) for communicating with the RFID readers. As soon as an RFID probe passes a receiving region of an RFID reader, the collected measurement values and, if appropriate, time stamps which indicate the times the measurement values were recorded are transmitted to the reader. It is thus possible to assign an exact position to at least said measurement values which were recorded in the receiving region. If the flow conditions are known, it is also possible using the time stamps to calculate the positions of the measurement value recording for measurement values which were recorded outside a receiving region.

Description

description

Device and method for determining measured values in a flowing medium

The invention relates to the determination of measured values in a fluid, in particular in a liquid medium, as well as the transmission of the determined measured values to an evaluation device.

In certain industrial facilities that use liquid media which flow through a channel or Rohrleitungssys ^¬ tem such as. In bioreactors, sewage treatment plants, fermentation plants etc., different Messun ^¬ gen must be made in the medium for process monitoring at various points of the channel system , Measurements should also be made at points in the process where measurements with conventional sensors are not possible or only possible with great effort. Depending on requirements, various parameters of the medium are determined by appropriate sensors, such as, temperature, pressure, pH, oxygen content, C02 content, etc., and if necessary, the Strömungsge ^¬ speed and direction. The measured values are transmitted via a cable or radio link to a central location and finally evaluated depending on the location of the respective measurement.

Such channel systems are predominantly closed and / or difficult to access systems. It decor with dark ^¬ tet therefore to be very expensive or even impossible, if necessary, to bring the sensors from the outside to the positions of interest in the medium to be examined. One approach to solving this problem is already in the instal ^¬ on the channel system sensors at known, likely to incorporate process-relevant positions determined to capture the parameters of interest to the relevant points measurements. With a strong spatial distribution of the channel system, however, this is also with great effort connected. Also, a subsequent installation of additional sensors is very expensive. In addition, the maintenance is Guidance and repair costs due to the severe Accessible ^¬ ness of the sensors disproportionately high.

The solution to these problems is the use of sensors that float in the medium or on the surface of the medium. These sensors are introduced into the medium at a suitable location and carried along by the flowing medium. The sensors determine their measured values for example. Permanent, to be voted ^¬ times or at specified time intervals and transmit the result or the measured values by means of wireless communication for evaluation to the central body. Simultaneously with the determination of the measured values, it must be possible to localize the sensor receiving the measured value as precisely as possible so that the respective measured value can be assigned to a specific position.

The sensor localization is based on radio signals, the sensor emits a communication signal that is registered by a receiver. For example. allows commu ^¬ cation with ultra-wideband signals (ultra wide band or UWB), a relatively accurate determination of the signal transit times between the communication participants, and can be deduced from the signal transit time on the path which the signal has passed. Another localization approach evaluates the signal strength of the received signal, assuming that the propagation channel of the radio waves is known. On this basis, the Ab ^¬ states between the participants and possibly then their positions can be determined with different accuracy depending on the method.

However, the problem with locating based on a runtime evaluation is that determining the runtimes is very time-consuming. A further problem is the dependency ^¬ the maturity of the medium, which makes the application of this approach, especially for inhomogeneous media almost impossible power. In addition, in almost all liquid media with a very high attenuation of the radio signals to be expected, which further complicates an evaluation of these signals for localization purposes. The localization with the help of the field strength measurement suffers additionally to the problem of the necessity of the

Knowledge of the propagation channel under the same problems as the runtime measurement.

It is therefore an object of the present invention to specify a possibility of a spatially resolved determination and transmission of measured values in a flowing medium.

This object is achieved by the inventions specified in the independent claims. Advantageous embodiments emerge from the dependent claims.

The device according to the invention for determining at least one measured value in a medium located in a channel system has:

- At least one RFID reader, which is to be arranged on the channel system such that a receiving area of the RFID reader is directed into the medium and thereby the

Reception area covers a limited space area of the medium, and

- At least one RFID probe with a sensor component for receiving the measured value and an RFID component for

Communication with the RFID reader.

The term RFID probe is understood to mean an RFID transponder or RFID tag which is additionally equipped with a sensor element.

In this case, the RFID probe is designed to

- swimming in the medium or on a surface of the medium,

to be taken along in the presence of a flow of the medium from the flowing medium, - Record by means of the sensor component at least one reading in the medium and

- To transmit a data set to the RFID reader by means of the RFID component, when the RFID probe in the

Receiving area of the RFID reader is located, wherein the record includes at least the recorded measured value.

In this case, a channel system is understood to be a system comprising one or more interconnected channels, where a channel is a closed pipeline, an "open" channel, a basin, etc.

The RFID probe is set up to record not only one but several measured values of the medium, wherein

- the measured values are recorded continuously or at certain intervals and

- At least a portion of the recorded measured values are transmitted together in the data set to the RFID reader, when the RFID probe is in the reception range of the RFID reader.

Thus, it is possible to detect the state of the medium at several different locations of the channel system and at different times.

The RFID probe may be configured such that

- Only then a recording of a measured value by the RFID probe takes place when the RFID probe is in the reception range of the RFID reader, or

- Only that measured value is transferred to the record that was recorded in the reception area of the RFID reader.

This ensures that the data record and thus the required storage and transmission capacities can be kept very small. In addition, comparatively accurate localization is only guaranteed for those measured values recorded in a reception area. These Therefore, an option is particularly suitable if the localization of the measured values is very important and at the same time no or only poorly localizable measured values can be dispensed with.

Alternatively, it is also conceivable that in the

Evaluation of the measured values, for example, in a central

Evaluation device only those measured values are taken into account, which were recorded in the reception area.

The RFID probe can furthermore be set up in order to generate a time stamp for each recorded measured value, which indicates the time of the recording of the respective measured value, wherein the time stamp is included in the data record for transmission to the RFID reader.

The time stamps can be used, for example, to calculate the position, for example model-based, for each recorded measured value on the basis of the time stamp assigned to the measured value and taking into account a flow velocity of the medium, at which the RFID probe at the time of recording the respective measured value (FIG. M) findings: has.

Thus, a localization of those measured values is possible that were not recorded in the reception area of an RFID reader.

Alternatively or additionally, for location purposes, the RFID probe can have a motion sensor, which detects the movement of the RFID probe and determines position data of the RFID probe as a function of time. In this case, movement data comprising the position data and the associated times at which the RFID probe was located at the positions are included in the data record for transmission to the RFID reader. For example. For example, the motion sensor may be realized by one (or more) acceleration sensor (s). In the simplest case, this can be done with very little wand determines whether it is a laminar flow and whether a simple model for calculating the position is sufficient.

This measure also contributes to a localization of those measured values is possible, which were not included in the reception area of an RFID reader.

Preferably, a plurality of RFID readers

intended. These are so spatially distributed on

Channel system to arrange that the respective receiving areas of the RFID readers are directed into the medium and thereby cover the reception areas different limited space area of the medium.

The RFID probe thus flows together with the medium past several readers and can optionally to each of the

Readers transmit a record with the recorded readings.

Ideally, the individual readers to the

relevant or critical points of the channel system

arranged in order to achieve as accurate as possible localization of the measured values. As a result of the large number of readers, we are thus able to monitor the condition of the medium at a large number of positions in the duct system

Depending on the accessibility of the channel system, for example RFID readers can also be repositioned and / or retrofitted

additional readers are added.

The RFID readers can be arranged so that the reception areas of at least two of the RFID readers partially overlap.

This ensures that in the overlap area a very accurate localization is possible. Furthermore, the RFID component and / or the

Sensor component of the RFID probe relate at least a portion of the energy required for operation from a radiated by the RFID reader electromagnetic field.

In this embodiment, the power supply in the RFID probe can be designed to be minimal. Ideally, the energy supply can be completely dispensed with.

An inventive channel system, which has at least one channel in which a medium can be guided, is equipped with a device according to the invention.

In a method according to the invention for the determination

at least one first measured value in one in one

Channel system located at least one RFID reader is arranged on the channel system such that a

Receiving area of the RFID reader is directed into the medium while the reception area a limited

Room area of the medium covers. At least one RFID probe, which contains a sensor component for receiving the first measured value and an RFID component for communicating with the RFID reader, is added to the medium. The RFID probe floats in the medium or on a surface of the medium and is entrained in the presence of a flow of the medium from the flowing medium. The RFID probe picks up the first measured value in the medium and transmits one

Record to the RFID reader when in the

Receiving area of the RFID reader is located, wherein the record includes at least the first measured value.

Preferably, the RFID probe takes a variety of

Measured values of the medium, where

- the measured values are recorded continuously or at certain intervals and

at least a part of the recorded measured values is transmitted jointly in the data set to the RFID reader, if the RFID probe is located in the reception area of the RFID reader.

The latter is to be understood as not

inevitably all measured values must be included in the data set and transmitted to the reader. For example. can

be provided that in the event that multiple readers are provided and taken on the way between a first and a second of the readers more readings and stored in the record, only the other

Measured values are transmitted to the second reader, since the previously recorded measured values have already been transmitted to the first reader. A measured value which is recorded at a time when the RFID probe is located in the receiving area of the RFID reading device is assigned a position which clearly depends on the position of the RFID reading device in whose reception area the RFID probe for the RFID reader is located Time of taking the reading.

Hereby, a comparatively accurate localization of the measured value or assignment of a position to the measured value is possible because with the position and orientation of the RFID reader relative to the channel system, the geometry of the

Reception area can be assumed to be known. The position to be assigned may be, for example, the center or center of gravity of the receiving area of the relevant reading device.

Alternatively, the position to be assigned could be, for example, a probable position of the probe resulting from flow measurements, which lies on the most probable trajectory of the probe through the reception area. Other approaches for determining the position to be assigned are of course conceivable. In the simplest case, the position of the reader

assigned.

The term position does not necessarily have one

include spatial position. Depending on the application it can suffice that the position is just a consecutive number oa. In other words, only a section of the channel system which is assigned to the measured value would be assigned

relevant reader with the corresponding running

Number is monitored.

In a further development, a time stamp is generated in the RFID probe for each recorded measured value, which time stamp

Time of recording the respective measured value indicates. The time stamp is included in the data set for transmission to the RFID reader and thus transmitted to the reader.

The time stamp can be used to calculate, after the transmission of the data record for each assigned measured value and taking into ^account a flow velocity of the medium, the position at which the RFID probe was located at the time of recording the respective measured value. This can be done, for example, model-based.

Depending on the flow behavior, a very accurate localization of the measured values can be achieved. In stationary / laminar flows at constant speeds, a very accurate localization is possible, while the localization of irregular or turbulent flows is less accurate.

Alternatively or additionally, for localization purposes, the movement of the RFID probe can be detected on the basis of the above-mentioned movement sensor, and position data of the RFID probe can be determined as a function of time. Transaction data comprising the position data and the associated times at which the RFID probe was located at the positions are included in the data record for transmission to the RFID reader.

In the event that several readers are distributed on the channel system, the RFID probe takes after transmitting the Record to a first of the plurality of RFID readers at least one additional reading and transmits a record to another of the plurality of RFID readers when the RFID probe is in the receiving area of the other RFID reader. In this case, the data record includes at least the further recorded measured value and possibly also the first already transmitted to the first reading device

Measured value.

In addition, the time of a transfer of a

Record to an RFID reader can be determined by

- The time of transmission determined by the RFID probe and shared with the record or as part of the

Record is transmitted with or

- The time of receipt of the record is registered on the RFID reader and added to the record or assigned.

The latter is to be understood that the time is taken either as part of the record in this or that the time is treated as the record characteristic parameter, but not itself is part of the record, but only together with the record from the reader, for example an evaluation is transmitted.

An average flow rate of the medium can be calculated

- using timestamps to readings of two

different RFID readers in their

Reception areas were recorded, or

- Based on the times of transfers of the records to the two different RFID readers.

With the present invention, a method and a system are presented in which RFID probes communicate their value or collected measured values to RFID readers arranged there at certain points in the system using RFID technology. This makes it possible to use the RFID Locate probes at specific reading points, namely where the RFID readers are installed, and communicate with them. With additional knowledge of the flow of the medium in the channel system, cached measured values can also be assigned to a position. Conversely, conclusions about the flow in the medium can be drawn from the visibility of individual RFID probes on certain readers.

In the solution according to the invention is thus exploited that the RFID technology due to the large number of different technical implementation forms has a high flexibility with respect. The use in different media. For example, by choosing a suitable transmission frequency, it is also possible to see in problematic, ie, for example, strongly attenuating media, to be communicated. The choice of frequency and technology (passive, semi-active, active) also determines the achievable accuracy of Lokali ^¬ tion and the extent of the data that can be exchanged on a reader from. The basic principle of the localization approach presented here is to evaluate the detection of the RFID probes at one or more reading points. If an RFID probe is detected at a reading point, it can be assumed that this probe is within a reading or receiving range determined by RFID technology. A probe even detected simultaneously by multiple, possibly be ^¬ neighboring RFID readers, which is conceivable in overlapping coverage areas, one can achieve a further improvement of the localization accuracy.

Further advantages, features and details of the invention will become apparent from the game Ausführungsbei described below and with reference to the drawings.

Showing:

FIG. 1 shows a duct system with a device according to the invention, 2 shows an RFID probe.

In the figures, identical or corresponding areas, components, component groups or method steps are identified by the same reference numerals.

1 shows a plan view of a simple channel ^¬ system 1, a fluid medium passes through the 2 in the duct system 1 with an inlet 10, a pipe line 20 with shut-off sections 21, 22, 23, on the out the liquid medium 2 is, and a drain 30 through which the medium 2, the channel ^¬ system 1 leaves again. Furthermore, an opening 40 is provided, via which RFID probes 50 can be introduced into the medium 2. The RFID probes 50 float in the medium 2 or on its surface and therefore flow with the medium 2 through the channel system 1, ie the average density of the probes 50 is adapted accordingly to the properties of the medium 2.

The spherical RFID probes 50 have, as shown in FIG. 2, at least one sensor component 51 with a media connection 52 and an electronic assembly 53, an RFID component 54, and a power supply 55. Via the media connection 52, a connection is established with the medium 2 with the aim of recording the measurement value of interest. Measured values can be, for example, the temperature, the pressure, the pH, the oxygen and / or CO 2 content of the medium, etc., and optionally flow parameters. The electronics module 53 may, for example, the measured value recording steu ^¬ ren, possibly store measured values, to make a preliminary evaluation of the measured values if necessary and / or transmit the measured values to the RFID component 54. The formation of such a sensor component 51 is known per se. Finally, with the aid of the RFID component 54, a data record is transmitted to a corresponding RFID reader 60/1 to 60/5, which at least contains the measured values and any further data. The RFID component 54 may be designed according to the type of a known, commercial ^¬ usual RFID transponder, which uses data from the RFID technology to an RFID reader transmit and possibly receive data from the RFID reader. The power supply 55 may be a rechargeable battery or a battery that provides the power needed to operate the sensor component 51 and the RFID component 54. Alternatively or additionally, the power supply 55 can be configured such that the required for operation of the RFID probe energy of au ^¬ SEN is supplied, eg. In the form of a coil 57 in which a voltage is induced via an external electromagnetic field.

Optionally, the RFID probe 50 can be equipped with a motion sensor 56, which in particular records irregularities, for example collisions, in the movement of the probe 50. Starting from the starting position, for example. Corresponding to the position of the opening 40, on the basis of measured values of Be ^¬ wegungssensors and at any time the position of the probe can be determined. Furthermore, an arrangement of at least one, vorzugswei ^¬ se but a plurality of RFID readers is provided 60/1 to 60/5. The RFID readers 60/1 to 60/5 are arranged at certain, known locations along the channel system 1, wherein the readers depending on the dimensions of the pipe 20, a more or less large range or a more or less extensive reception area 71, 72nd exhibit. A communication between the RFID probe 50 and an RFID reader 60 is only possible as long as the probe 50 is in the reception area of this reading device 60.

The pipeline 20 has a comparatively small diameter in the sections 21, 23, for which reason the RFID readers 60/1, 60/4, 60/5 arranged there are only available over a short range 71/1, 71/4, 71/5 feature. The section 22, however, has a much larger diameter. In order to ensure that all the RFID probes 50 passing through this section are registered by at least one reading device and that the RFID probe 50 has been detected by the RFID probe 50. If the data set is received by the nearest RFID reader, the RFID readers 60/2, 60/3 arranged here each have a larger receiving range 72/2, 72/3. In addition, these readers 60/2, 60/3 are arranged so that their receiving areas 72/2, 72/3 overlap at least in sections.

Furthermore, a central evaluation device 80 is provided, to which the RFID readers 60/1 to 60/5 transmit their data by radio. The data thus transmitted are in the

Evaluation device 80 evaluated with respect to the parameters of interest.

The operation of the system shown in Figure 1 is as follows: Upon introduction of an RFID probe 50 through the opening 40 in the flowing medium 2, the probe 50 and the sensor component 51 starts recording of reco ^¬ th MDH while the RFID Probe 50 flows with the medium 2 through the channel system 1, the sensor component 51, for example. At regular intervals measured values M and stores them in the electronic assembly 53 from. Simultaneously with the recording of a measured value M of the time, the measured value ^¬ also recording for example. With the aid of a time stamp T ^¬ re gistriert and assigns the measurement value M Certified in the storage means. The storage of the measured values M and the time stamp T can of course also be carried out in a corresponding memory device of the RFID component 54.

As soon as the RFID probe 50 reaches the receiving area 71/1 of the RFID reader 60/1, a data set D is transmitted to the RFID reader 60/1 with the aid of the RFID component 54 of the probe 50, which at least one or more measured values M recorded up to this point in time. ^¬ additionally to the data D may be the corresponding time stamp T and / or an identification number ID, with which the the data D transmitted RFID probe 50 is uniquely identifiable. Possibly. the data record D may additionally or alternatively to the time stamp T have a time stamp Ί " point, which indicates the time of transmission of the data set D, as is generally assumed that advises Lesege ^¬ 60 and probe 50 no precise common time base besit ^¬ zen. Equivalently hereby, this time stamp or point in time Ί "can also be determined on the respective RFID reader 60 by registering the point in time Ί" at which a data record D is received by the RFID reading device 60. This time Ί "is then assigned or added to the received data record D.

In the event that the RFID probe 50 has a motion sensor 56, the data record D contains the motion data recorded with the motion sensor 56, which on the one hand contain position information and on the other hand the time points assigned to the position information. On the basis of the movement data, it is therefore easy to reconstruct for each time point at which position the RFID probe 50 was located. During and after the transmission of the data set D in the corresponding RFID reader 60/1 recording of measured values is continued as described above ^¬ and storing them. Once the RFID probe 50 reached overall in the lobby 72/2 and 72/3 of the next RFID reader 60/2 or 60/3, the corresponding new data set D of this Le ^¬ segerät is transmitted. The new data record can in this case only after transfer to the first reader-housed 60/1 include ^¬ NEN measured values or all measured values that have been recorded in the medium 3, after the introduction of the probe 50th The same happens when the probe 50 the übri ^¬ gen RFID readers 60/4, 60/5 happens.

As a rule, a multiplicity N of RFID probes 50 / i with i = 1, 2, 3, N are introduced into the medium 2. It can be provided that the different probes 50 / i determine different measured quantities of the medium 2. Alternatively or additionally, some or all of the probes 50 / i may also each have a plurality of sensor components, with which in turn Different measured variables can be determined. Each RFID probe 50 / i transmits to the RFID reader 60/1 to 60/5 a data set Di comprising one or more measured values M _± , a time stamp ΊΊ, possibly a time stamp T and / or an identification number I Di as soon as they are into the respective receiving area 71, 72 passes.

Depending on the flow behavior in the channel system 1, the assignment of a recorded measured value M to a specific location P in the channel system 1 is only more or less exact despite timestamps. For example. in the case of a pipeline in which the medium 2 and with it the probe 50 flows at a comparatively constant speed, the time stamp T, T "can easily be used to calculate the position at which the probe 50 must have been located at the respective measuring times, when the flow rate is known. such a situation is, for example, in section 23 of the duct system shown in Figure 1 before. in order to calculate the flow rate Kgs ^¬ nen in such a piping system, for example. two timestamp Tl ', T2' are used, both the Time of record transfers to the RFID readers 60/4 and 60/5 mark, which of course assumes that the Posi ^¬ tions of these two RFID readers are known.The Strö ^¬ mungsgeschwindigkeit is then calculated as a quotient of the between these RFID Readers lying path and the difference of the time stamps Tl 'and T2' With knowledge of the flow ^¬ speed könn Then, on the basis of the data set transmitted to the RFID reader 60/5, those measured values which were recorded on the way between the RFID readers 60/4 and 60/5 are assigned the positions on which the corresponding time stamps T are assigned Measurements were taken.

In general and in particular in duct systems in which there is no sufficiently constant flow velocity or can be determined, the assignment of a measured value to a specific location in the duct system is more complex. Here are the most accurate measurements to locate those which were recorded in the immediate vicinity of one of the RFID readers. Since the positions of the RFID readers are known, a position can easily be assigned to this measured value. Such a measurement is in each case transmitted DA cost rate for example. Characterized identifiable, that the corresponding time stamp T and the time stamp Ί "of sending the Da ^¬ tensatzes D match as far as possible. The higher the Dif ^¬ ference between T and Ί" becomes, the larger is also the inaccuracy of the localization, since the flow velocity is not sufficiently known. Furthermore, the Ge ^¬ accuracy of localization depends on the size of the receive preparation ^¬ ches of each RFID reader.

Another way of identification of the most accurately localized reading of a data record lies in the fact that the time stamps T are the measured values M to the time ver ^¬ equalized to that of the record at the RFID reader is received, wherein one measured value is selected whose time ^¬ stamp is the least deviates from this date.

The simplest way of reading identification is however, is zuwählen the measured value with the most recent time stamp from ^¬. In this case, no further data processing is necessary, but ultimately that measured value is selected in the data record which was last recorded or stored.

An alternative to the selection of a measured value from the data set ^¬ is that only then a measured value listed is taken when the probe of the coverage area

RFID reader arrives, instead of continuously or regularly ^¬ measure at certain intervals. The measured value recording itself, ie the time at which the measured value is recorded, can be triggered by the respective reading device or by a field emitted by the reading device. Of course, the measurement must not be limited to the inclusion of only a single reading, but it is conceivable several measurement values ^¬ record while the probe within range located. From these measured values, for example, an average value can be calculated, to which a position is then assigned which is based on the position or the identity of the corresponding RFID reading device. This position can be assigned, for example., The focus or the focal point of the reception preparation ^¬ ches 71, 72 or it can be the position of the corresponding RFID reader. It would also be conceivable that the position to be assigned lies on the most probable trajectory of the RFID probe through the reception area. In this case, it is assumed that the cross section of the pipe system, which is located in the receiving area of the reader, is not uniformly flowed through, but that the probability that the probe flows, for example. At the edge of the channel past the reader is greater than that in the middle of the channel passes the reader. This probability distribution can be determined with knowledge of the dimensions of the pipe system, for example. Modellba ^¬ Siert.

The probe 50 or its RFID component 54 and possibly also the sensor component 51 can be designed as a passive system, which obtains the energy required for operation from the RFID field of the reading device. As soon as the RFID probe 50 enters the receiving area of an RFID reader, the measured value recording begins. The transfer of the recorded measured values to the RFID reader can, for example, be carried out continuously, as long as the probe 50 is in the receiving area. Once it leaves the lobby, both the measured value ^¬ recording and data transmission to the reader ends. An increase in the accuracy of the assignment of a position in the channel system 1 at a recorded with an RFID probe 50 measured value M, that is, an increase in the accuracy of the localize ^¬ tion of the measured values, alternatively or additionally can be achieved that as small as possible, possibly overlapping , And as many reception areas 71, 72 realized ^¬ who. To achieve this goal, several optimization ^approaches are available. These can be combined of course, with any pros and cons of different approaches have to be ^¬ handy depending on the situation weighed against each other:

- Depending on the medium 2, RF fields of different frequencies propagate to different extents. Thus, the size of the reception range can be selected within certain limits via the suitable choice of the frequency range and the transmission power of the field emitted by the RFID reader 60/1 to 60/5 and / or by the RFID probe 50.

- The use of passive RFID components leads to very small reception areas, semi-active allow much larger reception areas and active components allow to ^¬ additionally the scale of the reception area on the selection of transmit power. However, these three differing ^¬ chen realizations other properties that need to be considered are (size, power, etc.). For example, passive RFID components can operate without their own power supply and thus enable a comparatively small size and a low weight. Active or semi-active components are typically equipped with a battery or other geeigne ^¬ th power, which has a negative effect on size and weight.

- If small receiving regions chosen 71, 72, can increase the number of necessary reading devices 60 according to need, especially in the event of the need for flächende ^¬-bridging localization. If only the values at particular positions of the channel system 1 are of interest, then it is sufficient to install an RFID reader 60 with a narrowly limited reception area 71, 72 only at exactly the relevant points.

This summary can basically distinguish between two Ansät ^¬ zen for localization of the measured values: 1) If the flow velocity is sufficiently constant, known or can be determined, the time stamps can be used to calculate the positions at which the measured values assigned to the time stamps were recorded. Here is a relatively wide-meshed network of RFID readers suffi ^¬ accordingly.

2) If the flow behavior is not known or too complicated, a comparatively close-meshed network of RFID readers should be set up as required, since a calculation of the positions outside the reception ^ranges is too unreliable. In extreme cases, only those measurements exact positions can be assigned recorded in Empfangsbe ^¬ rich of an RFID reader. For less complicated flow behavior and those measured values can be assigned to positions which, while outside a coverage area, however, were ^¬ taken in its immediate vicinity, so that again, for example, based on the time stamp. Model-based a sufficiently accurate determination of the position of the data logging is possible. The best result can be achieved if as many RFID readers as possible are arranged with the smallest possible reception area and as close together as possible.

An increase in the quality and reliability of the information about the state of the medium 2 in the channel system 1 that can be derived with the system comprising RFID readers 60 and RFID probes 50 can be obtained by increasing the number of measured values transmitted via the RFID readers 60 to the evaluation device 80 be achieved. For this purpose, the number of measured values can be increased by shortening the measuring cycle of each individual RFID probe 50. Alternatively or additionally, the number of measurements can also be increased by passing a larger number of RFID probes 50 through the channel system 1. Both measure ^¬ took lead to an increase in the per unit volume and / or per unit of time available readings. This can be done by suitable mathematical methods (eg Filter functions) a high-quality measured value can be determined.

Possibly. pending calculations can be performed in the evaluation unit 80 or locally in the respective data record D receiving RFID reader. Basically, it is advantageous to perform any calculations centrally in the evaluation ^¬ unit 80 so that the readers 60 only serve to read out their reception areas 71, 72 passing RFID probes 50 and provide, if necessary, with power and the read out data to the To forward evaluation unit 80 on.

Possibilities and advantages below listed arise from the fact that not as previously established for the RFID probes 50 in the manner provided herein use a mesh network with continuous communication link, but RFID technology and the associated parameterization and Ska ^¬ lierbarkeit is used to To determine measured values directly in the medium, save them if necessary and communicate them to the higher-level system at the next opportunity:

- possibility of recording of measured values in many differing ^¬ chen positions directly in the medium without permanent communication connection of the probe to a central location;

- Possibility of simultaneous determination of the flow rate of the medium, especially in piping systems with largely (at least in sections) constant line cross-section;

- accurate localization of at least those measured values that were recorded directly in the sensitivity range of an RFID reader;

- Possibility of data logging even at positions Zvi ^¬ rule the sensitivity regions of the readers;

- Possibility of selectable temporal resolution via suitable parameterization of the measuring cycle in the RFID probe; Quality of the localization of the number of RFID readers and suitable dimensioning of the reception areas impressive ^¬ flussbar;

Quality of the measurement can be influenced by the number of RFID probes inserted;

Possibility of reusing the RFID probes;

Availability of active, semi-active or passive RFID probes, i. Possibility of communication without energy expenditure when using passive probes;

Possibility of using a completely energy-free variant of the RFID probe when the probe derives the energy from an electromagnetic field radiated by the reading device; Use of rechargeable energy storage in active and semi-active RFID probes;

Possibility of localization and additional statements about the flow behavior of the medium 2 via the integration of a motion sensor in the RFID probe.

Claims

claims

1. Device for determining at least one measured value (M) in a medium (2) located in a channel system (1), comprising:

- At least one RFID reader (60), which on such

Channel system (1) is to be arranged, that a receiving area (71, 72) of the RFID reader (60) is directed into the medium (2) and thereby the receiving area (71, 72) covers a limited space region of the medium (2), and

at least one RFID probe (50) having a sensor component (51) for receiving the measured value (M) and an RFID component (54) for communicating with the RFID reader (60),

wherein the RFID probe (50) is formed to

to float in the medium (2) or on a surface of the medium (2),

- In the presence of a flow of the medium (2) of the

flowing medium (2) to be taken

- Receive by means of the sensor component (51) at least one measured value (M) in the medium (2) and

to transmit a data set (D) to the RFID reading device (60) by means of the RFID component (54) when the RFID probe (50) is located in the receiving area (71, 72) of the RFID reading device (60), wherein the data set (D) at least the

recorded measured value (M) includes.

2. Device according to claim 1, characterized in that the RFID probe (50) is adapted to receive a plurality of measured values (M) of the medium (2), wherein

- the measured values (M) continuously or in specific

time intervals are recorded and

the recorded measured values are transmitted together in the data set to the RFID reading device (60) when the RFID probe (50) is located in the receiving region (71, 72) of the RFID reader

Reader (50) is located.

3. Device according to one of the preceding claims, characterized in that the RFID probe (50) is arranged such that

- Only then a recording of a measured value by the RFID probe (50) takes place when the RFID probe (50) in

Receiving area (71, 72) of the RFID reader (60)

located, or

- Only that measured value is transmitted to the record (D), which was recorded in the receiving area (71, 72) of the RFID reader (60).

4. Device according to one of the preceding claims, characterized in that the RFID probe (50) is arranged to generate a time stamp (T) for each recorded measured value (M), which time of recording of the

indicates the respective measured value (M), the time stamp (T) being included in the data record (D) for transmission to the RFID reading device (60).

5. Device according to one of the preceding claims, characterized in that the RFID probe (50) has a BEWE ^¬ movement sensor (56) which detects the movement of the RFID probe (50) and position data of the RFID probe (50) in Determined depending on the time, wherein movement data comprising the position data and the associated times at which the RFID probe (50) was located at the positions in the record (D) for transmission to the RFID reader (60) be recorded.

6. Device according to one of the preceding claims, characterized in that a plurality of RFID readers

(60/1, 60/5) are provided, which are so spatially

distributed to the channel system (1) are to be arranged that the

respective receiving areas (71/1, 71/4, 71/5, 72/2, 72/3) of the RFID readers (60/1, 60/5) are directed into the medium (2) and thereby the receiving areas (71 / 1, 71/4, 71/5, 72/2, 72/3) cover different, limited spatial areas of the medium (2).

7. Device according to claim 6, characterized in that the receiving areas (72/2, 72/3) of at least two of the RFID readers (60/2, 60/3) partially overlap.

8. duct system (1) with at least one channel (20) in which a medium is feasible, with a device according to one of the preceding claims.

9. A method for determining at least a first measured value (M) in a in a channel system (1) located medium (2), wherein

- At least one RFID reader (60) is arranged on the channel system (1) in such a way that a reception area (71, 72) of the RFID reader (60) is directed into the medium (2) and thereby the reception area (71, 72) a limited

Covering the area of the medium (2),

- At least one RFID probe (50) having a sensor component (51) for receiving the first measured value (M) and an RFID component (54) for communication with the RFID reader

(60) is added to the medium (2), wherein the RFID probe (50) in the medium (2) or on a surface of the

Medium (2) floats and in the presence of a flow of the medium (2) is taken from the flowing medium (2), wherein the RFID probe (50)

- receives the first measured value (M) and

- Transfers a record (D) to the RFID reader (60) when the RFID probe (50) in the receiving area (71, 72) of the RFID reader (60), wherein the record (D) at least the first Measured value (M) includes.

10. The method according to claim 9, characterized in that the RFID probe (50) receives a plurality of measured values (M) of the medium (2), wherein

- the measured values (M) continuously or in specific

time intervals are recorded and

- Transfer at least a portion of the recorded measurements together in the data set (D) to the RFID reader (60) is when the RFID probe (50) in the reception area (71, 72) of the RFID reader (60) is located.

11. The method according to any one of claims 9 or 10, characterized in that

Receiving area (71, 72) of the RFID reader (60)

located, or

12. The method according to any one of claims 9 to 11, characterized in that a measured value (M) belonging to a

Is received at the time when the RFID probe (50) in the reception area (71, 72) of the RFID reader (60)

is assigned, a position that is clearly dependent on the position of the RFID reader (60), in its receiving area (71, 72), the RFID probe (50) for

Time of taking the reading.

13. The method according to any one of claims 9 to 12, characterized in that in the RFID probe (50) to each

recorded measured value (M) a time stamp (T) is generated which indicates the time of recording of the respective measured value (M), wherein the time stamp (T) in the data record (D) for transmission to the RFID reader (60) becomes.

14. The method according to claim 13, characterized in that for each measured value recorded (M) on the basis of the measured value (M) respectively associated time stamp (T) and taking into account a flow velocity of the medium (2) that position is calculated at which the RFID probe (50) at the time of recording the respective measured value (M).

15. The method according to any one of claims 9 to 14, characterized in that the RFID probe (50) has a movement sensor (56) which detects the movement of the RFID probe (50) and position data of the RFID probe (50 ) as a function of time, wherein movement data comprising the

Position data and the associated time points at which the RFID probe (50) was located at the positions in the

Record (D) for transmission to the RFID reader (60) are included.

16. The method according to any one of the preceding claims, characterized in that a plurality of RFID readers (60/1, 60/5) so spatially distributed on

Channel system (1) is arranged, that the respective

Reception areas (71/1, 71/4, 71/5, 72/2, 72/3) of the RFID

Readers (60/1, 60/5) are directed into the medium (2) and the receiving areas (71/1, 71/4, 71/5, 72/2, 72/3) have different, limited spatial areas of the medium ( 2) cover.

17. The method according to claim 16, characterized in that the RFID probe (50)

- After transferring the record (D) to a first

(60/1) of the plurality of RFID readers (60/1, 60/5) receives at least one further measured value and

- Transfers a record (D) to another (60/2) of the plurality of RFID readers (60/1, 60/5) when the RFID probe (50) in the receiving area (71, 72) of the further RFID Reading device (60/2) is located, wherein the data record (D) at least the further recorded measured value (M)

includes.

18. The method according to any one of claims 9 to 17, characterized in that a time (Τ ') of a transmission of a data set (D) to an RFID reader (60) is determined by - The time (Τ ') of the transmission of the RFID probe (50) is determined and transmitted to the RFID reader (60) or

the time (Τ ') of the reception of the data record (D) on

RFID reader (60) registered and the record

assigned or added.

19. The method according to any one of claims 9 to 18, characterized in that an average flow velocity of the medium (2) is calculated

- Using time stamps (T) to measured values (M), which were recorded by two different RFID readers (60/4, 60/5) in their reception areas (71/4, 71/5), or

on the basis of the times (Τ ') of the transmissions of the data sets (D) to the two different RFID readers (60/4,

60/5).