Patent Application
20220247596
The invention relates to a sensor hub, a sensor system, a method for transmitting sensor signals, and a computer-readable storage medium.
Control cabinets are often equipped with a variety of sensors to monitor the environment of sensitive and expensive equipment in the control cabinet. For example, temperature sensors or humidity sensors can be provided for monitoring. In addition, production plants are also equipped with a variety of sensors to ensure the function of the production equipment.
Sensors are usually connected via an analog or digital interface to a user module, e.g. a PLC, which regularly reads out the sensors. According to the current state of the art, digital sensors are 1-bit sensors that do not transmit measured values, but only states (e.g. on or off) in the form of bits. Analog sensors provide measured values, but no information about themselves. This means that analog sensors are not addressable and cannot be identified if several sensors transmit their data via a single connection, e.g. a bus.
This arrangement has the disadvantage that complex cabling must be laid from the control cabinet or from the production plant to the user module (higher-level control unit).
To solve these disadvantages, it is known to connect several binary sensors to the user module via a sensor hub. An IO-Link data interface, for example, can be provided between the sensor hub and the user module. In the case of an IO-Link data interface, a so-called IO-Link master which ensures communication between the sensor hub and the user module must be connected between the sensor hub and the user module. Towards the sensor hub, this is an IO-Link point-to-point connection. Towards the user module, this is usually a fieldbus connection.
With a direct connection of analog sensors to the user module, it is disadvantageous that a conversion of the analog data into user data, such as temperature, must be carried out. Furthermore, in the state of the art for binary sensors, it cannot be detected which sensor is connected to which port of a sensor hub. In the case of analog sensors, it must be specified on the user side in a register via a corresponding coding which sensor may be connected to which port, since the analog sensors themselves cannot provide any information about model and type.
It is therefore the object of the present invention to eliminate the disadvantages present in the prior art. In particular, it is an object of the invention to simplify communication with a plurality of sensors, in particular digital sensors, in particular via an IO-Link connection. Furthermore, it is in particular an object of the invention to simplify the wiring of a control cabinet.
The object may be achieved by a sensor hub, a sensor system, a method for transmitting sensor data, and/or a computer-readable storage medium as set forth in various ones of the accompanying claims.
The object is solved in particular by a sensor hub, comprising:
A core feature of the invention is that at least two sensors are addressable via a sensor hub. Thus, the sensors are also individually identifiable by a device connected to the sensor hub. This is achieved by forwarding the addresses as part of the sensor data. The cabling is simplified because the sensor data is transmitted to the user device via a single transmission medium.
For example, it may be provided that the sensors send the sensor signals to the sensor hub via an I2C bus. The computer device can be designed to convert the sensor signals into an IO-Link compatible data format and to aggregate them in this data format, wherein the only transmission medium can be formed by an IO-Link compatible transmission medium.
It is therefore made possible to code the sensors via addresses. This enables a unique identification and query of the defined sensors. A previous setting on the user side is therefore not necessary. In addition, there is the advantage that, despite the point-to-point connection between the sensor hub and the user side, it is easy to determine which sensors are connected and which sensor supplies which values when at least two sensors are connected.
It is further conceivable that the computer device may be configured to process voltage values, in particular digital voltage values which may be indicated by the sensor signals, to generate the sensor data and to determine temperature values, particle density values, humidity values, gas concentration values, vibration intensity values and/or other physical values using the sensor signals.
It is thus further possible that the desired temperature values, etc., are transmitted directly, so that a calculation of these values in a user device is not necessary.
In one embodiment, the sensor signals may indicate sensor readings.
In the context of this application, the term sensor readings may mean digitally encoded values indicated by the sensor signals. Sensor readings may indicate a series of measured values measured on a continuous scale.
Therefore, the sensor signals of different predefined sensors can be received and processed by the sensor hub.
In one embodiment, the sensor signals may indicate a temperature, a humidity, a particulate matter indication, a vibration indication, a gas indication, and/or other physical or chemical measurements.
In one embodiment, the at least one sensor communication device may be configured to be connected to at least one fieldbus system for communication with the at least two sensors.
The at least two sensors can therefore be connected to the sensor hub via a fieldbus system. For example, the known I2C bus can be used. In this case, the field bus system can be of four-wire design, for example. It is also conceivable that several sensors can be connected via a sensor communication device. In this case, a field bus system can be used which can be designed to address several participants, i.e. sensors, via a single transmission medium. Thus, a very flexible solution is provided with which different sensors can be connected to the sensor hub.
In one embodiment, the transmitting device may be configured to periodically transmit the sensor data.
In one embodiment, the sensor data within a transmission period may comprise a data packet, wherein the data packet may specify a transmission channel, a sensor status, a sensor type, and/or at least one sensor reading.
It is therefore possible to transmit data from a single sensor over the single transmission medium, wherein the data packet allows the type of sensor to be identified. Thus, a connected user device can easily determine which type of sensor provided the data.
In one embodiment, the sensor data may comprise a data packet within a transmission period, wherein the data packet indicates at least two sensor types, a sensor status, and/or at least one sensor reading for one of the at least two sensor types.
It is therefore also possible for a single data packet to have data fields for each type of sensor, so that the corresponding data is stored there. It is then not necessary for a connected user device to determine which type of sensor sent the data, since the data field used already implies this.
In one embodiment, the computer device may be configured to transmit a sensor address to a sensor using the at least one sensor communication device.
In order to determine whether a sensor is connected to a port of the sensor hub, the sensor hub may be configured to transmit a sensor address via the at least one sensor communication device.
In one embodiment, the computer device may be adapted to process a response message received from a sensor via the at least one sensor communication device in response to a/the transmitted sensor address, and to determine the type of sensor using the response message.
The sensor may therefore be configured to transmit a response message to the sensor hub in response to receiving a sensor address. For example, the sensor may be configured to transmit a response message to the sensor hub if the received address corresponds to a sensor address stored on the sensor. If the address transmitted by the sensor hub does not correspond to the sensor address stored on the sensor, the sensor may be configured to not send a response message to the sensor hub.
The sensor hub can thus determine whether, and if so, what type of sensor is connected to the sensor hub via the at least one sensor communication device by receiving or not receiving a response message. This communication may also verify the operation of the sensor. The response message can then be interpreted by the sensor hub as a life signal.
In one embodiment, the computer device may be adapted to determine that no sensor is connected to the at least one sensor communication device if no response message is received in response to a/the transmitted sensor address.
Accordingly, determining whether no sensor is connected to the at least one sensor communication device is implemented by the computer device. Thus, overall, a very efficient embodiment is disclosed for determining what type of sensor is connected to the at least one sensor communication device and whether any sensor is connected at all.
The object is also solved in particular by a sensor system comprising:
Similar or identical advantages are obtained as have already been described in connection with the sensor hub.
In one embodiment, the at least one sensor may be a temperature sensor, a humidity sensor, a gas sensor, and/or a particle sensor, etc.
Similar or identical advantages are obtained as have already been described in connection with the sensor hub.
The object is also solved in particular by a method for transmitting sensor data, comprising the following steps:
In one embodiment, the method may comprise:
Similar or identical advantages are obtained as have already been described in connection with the sensor hub.
The object is further solved in particular by a computer-readable storage medium containing instructions for causing at least one processor to implement a method as described above when the instructions are executed by the at least one processor.
Similar or identical advantages are obtained as have already been described in connection with the sensor hub.
Further embodiments will be apparent from the subclaims.
The foregoing summary, as well as the following detailed description of the preferred invention, will be better understood when read in conjunction with the appended drawings:
Four sensors 11, 12, 13, 14 are arranged in the production plant 10, i.e. a gas sensor 11, a fine dust sensor 12, a first temperature sensor 13 and a second temperature sensor 14. In addition, further components not shown are arranged in or at the production plant 10, such as a control programmable unit (PLC). Of course, in a further exemplary embodiment it is conceivable that only sensors of one type are used, for example only humidity sensors.
The sensors 11, 12, 13, 14 are each connected to the sensor hub 20 via fieldbus connections 2, for example an I2C bus connection. One way of communication, which is also used by the I2C bus, is characterized in that a four-wire connection is used, wherein one wire is used for the transmission of a clock signal and the second wire is used as a data line (¾ for the operating voltage of the sensor). Both wires are connected to a supply voltage via pull-up resistors. The fieldbus 2 is designed as a master-slave fieldbus. This means that a communication in the shown exemplary embodiment is initiated by the master. In the exemplary embodiment, the sensor hub 20 is designed as a master and the sensors 11, 12, 13, 14 are each designed as a slave.
The sensors 11, 12, 13, 14 connected via the fieldbus 2 can be addressed via addresses by the sensor hub 20. This means that the master transmits an address to the sensors 11, 12, 13, 14 via the field bus 2 and the sensor 11, 12, 13, 14 to which the address is to be assigned responds with sensor signals indicating the measured values.
The sensors 11, 12, 13, 14 are designed to transmit their measured values as sensor signals to the sensor hub 20. The sensor hub 20 is described in detail in connection with
A point-to-point connection is preferably used between the sensor hub 20 and the user device 5, for example an IO-Link connection 3.
A point-to-point connection is characterized in that no other devices are connected between two connected devices. Thus, with a point-to-point connection, only one other device can be connected to a port of a device.
With the invention described, it is now made possible to receive the sensor signals of a plurality of sensors 11, 12, 13, 14 via a connection on the user device 5. Furthermore, it is now possible to determine from which sensor which sensor data originates. Thus, in the exemplary embodiment of
In the context of this application, the connections 21, 22, 23, 24 are also referred to as sensor communication devices.
The sensors 11, 12, 13, 14 transmit respective sensor signals 27, 27′, 27″, 27′″ to the computer device 25 via the connections 21, 22, 23, 24. The computer device 25 is configured to receive and process the sensor signals 27, 27′, 27″, 27′″. For example, the computer device 25 is adapted to calculate a temperature from voltage values 27 transmitted by a temperature sensor 13. In this respect, the computer device 25 may be appropriately preconfigured so that it is possible to assign a corresponding temperature to a digital data packet.
However, it is also conceivable that the computer device 25 performs more advanced calculations, such as determining an average value over a certain time interval, for example 24 hours.
Finally, in some exemplary embodiments, the computer device is adapted to form a virtual sensor. This means that the computer device 25 is adapted to process the values from at least one sensor 11, 12, 13, 14 and to transmit them as sensor data to the user device 5. For example, it is possible to create a virtual sensor which always indicates the temperature average of the last 24 hours.
The computer device 25 may further comprise a memory device in which, for example, the sensor data is temporarily stored. The addresses of the sensors 11, 12, 13, 14 may also be stored there.
The processed sensor signals 27, 27′, 27″, 27′″ are additionally aggregated by the computer device 5 as sensor data 28. This means that the sensor signals 27, 27′, 27″, 27′″ can be transmitted further together. For this purpose, the sensor data 28 are sent to a transceiver 26 which transmits the sensor data 28 to the user device 5.
The transceiver 26 may also be referred to as the transmitting device.
In the initialization step 301, the sensor hub 20 is switched on and thus supplied with power. Furthermore, it is checked whether all sensors 11, 12, 13, 14 known to the sensor hub 20 have already been initialized. For this purpose, the sensor hub 20 has a memory device in which a plurality of sensor addresses are stored. Each address is assigned a sensor type and an indication as to whether the associated sensor 11, 12, 13, 14 is already initialized.
In the test step 302, the computer device 25 of the sensor hub 20 checks whether at least one address has not yet been initialized. If this is the case, the method continues with the transmission step 305. If all sensors 11, 12, 13, 14 have already been initialized, the method ends with the end step 308.
In the transmission step 305, a sensor address 304 which is not yet initialized is read out from the memory device 303. The address 304 is transmitted in the transmission step 305 via a sensor communication device 21, 22, 23, 24.
If a response to the transmitted address 304 is received in the receiving step 306, an assignment from the address 304 to the sensor communication device 21, 22, 23, 24 used is stored in the storing step 307. Thus, from this point on, it is known which sensor 11, 12, 13, 14 can be reached via which sensor communication device 21, 22, 23, 24.
If no response is received to the sending of address 304 at step 306, the method proceeds to step 301.
The sensor data 7 may also include the data for all channels, i.e. sensor communication devices or connections 21, 22, 23, 24. Thus, with reference to FIG. 1, the sensor data 7 comprises the data of
The described exemplary embodiment has the advantage that little process data must be transmitted, since the data necessary for a sensor can always be precisely transmitted in a compact manner at all times. A disadvantage is that the status S1 must be evaluated in order to determine what data is being transmitted.
This disadvantage is addressed by the exemplary embodiment of
The definition of the sensor types T1-T4 in the sensor data 8 is thereby fixed, so that it can be recognized from the use of the data fields D1-D4 which type of data is involved. For example, if T1 is specified as a temperature sensor, it can be recognized from the use of the data field D1 with a value that the data in the data field D1 is temperature data of a connected temperature sensor 13. Thus, no status needs to be read out and interpreted.
It will be appreciated by those skilled in the art that changes could be made to the embodiments described above without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but it is intended to cover modifications within the spirit and scope of the present invention as defined by the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2019 112 230.9 | May 2019 | DE | national |
This application is a Section 371 of International Application No. PCT/EP2020/062687, filed May 7, 2020, which was published in the German language on Nov. 19, 2020 under International Publication No. WO 2020/229292 A1, which claims priority under 35 U.S.C. § 119(b) to German Patent Application No. 10 2019 112 230.9, filed May 10, 2019, the disclosures of which are incorporated herein by reference.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2020/062687 | 5/7/2020 | WO | 00 |
