DIAGNOSTIC THE OPERATION OF AN EDGE DEVICE

Description

[0001] The invention relates to a method for diagnosing the operation of an edge device, wherein the edge device is in communication connection with a plurality of network participants via one or more communication networks, wherein the edge device is in communication connection with a database via a further communication network, wherein at least one first application runs on the edge device, and wherein the edge device queries data from those network participants which are defined via a first filter accessible to the first application.

[0002] Field devices are already known from the state of the art and are used in industrial plants. They are widely employed in process automation as well as in manufacturing automation. In principle, field devices are defined as all devices that are used close to the process and that provide or process process-relevant information. Thus, field devices are used to acquire and / or influence process variables. Measuring instruments or sensors are used to acquire process variables. These are used, for example, for measuring pressure and temperature, conductivity, flow rate, pH, level, etc., and acquire the corresponding process variables such as pressure, temperature, conductivity, pH value, level, and flow rate. Actuators are used to influence process variables.These include, for example, pumps or valves that can influence the flow of a liquid in a pipe or the fill level in a container. In addition to the aforementioned measuring devices and actuators, field devices also include remote I / Os, radio adapters, and generally any devices located at the field level.

[0003] A large number of such field devices are produced and distributed by the Endress+Hauser Group.

[0004] In modern industrial plants, field devices are typically connected to higher-level units via communication networks such as fieldbuses (Profibus®, Foundation® Fieldbus, HART®, etc.). These higher-level units are usually control systems or automation units, such as a PLC (Programmable Logic Controller). The higher-level units are used, among other things, for process control, process visualization, process monitoring, and commissioning of the field devices. The measured values ​​acquired by the field devices, especially sensors, are transmitted via the respective bus system to one (or possibly several) higher-level unit(s). Data transmission from the higher-level unit to the field devices via the bus system is also necessary, particularly for configuring and parameterizing field devices and controlling actuators.

[0005] An edge device is a device that enables data from field devices to be transported to the cloud (a cloud-enabled database accessible via the internet) as part of digital services. An edge device can be configured to run multiple services. One or more apps (usually in the form of web applications) are provided to a user of a digital service. A digital service might, for example, require cyclical access to one or more parameters from one or more field devices.

[0006] Each access to a field device requires a certain execution time, which largely depends on the transmission rate of the network protocol used, the methods employed within that protocol (e.g., master-slave communication), the execution times of the access within the field device, and the runtimes within the edge device itself. For cyclic access, cycle times are defined that are based on the dynamics of a parameter value of the field device and thus ultimately depend on the dynamics of the physical process being monitored by the field devices.

[0007] If a large number of digital services are executed, each triggering cyclical accesses, or if a large number of field devices are defined for querying, the simultaneous execution can lead to exceeding the predefined cycle time. Since this will result in a violation of the sampling theorem, the correct functioning and evaluation of the app will no longer be guaranteed. Whether the cycle time limit will be exceeded cannot be determined in advance, as execution times can exhibit random variations related to the specific configuration of an edge device.

[0008] Patent publication US 2019 / 320451 A1 discloses a method for planning the communication of field devices in a wireless network of an industrial process system.

[0009] The invention is based on the objective of presenting a method which enables verification of the correct querying of field devices using an edge device.

[0010] The task is solved by a method for diagnosing the operation of an edge device, wherein the edge device is in communication connection with a large number of network participants via one or more communication networks, wherein the edge device is in communication connection with a database via another communication network, wherein at least one first application runs on the edge device, and wherein the edge device queries data from those network participants which are defined via a first filter accessible to the first application, comprising: Determining an initial cycle time of the first application, wherein the initial cycle time denotes the respective time interval between two queries of a network participant defined in the first application; wherein the initial cycle time is determined by summing the respective query times of each individual network participant defined in the first application, wherein each query time consists of an active query time component and a passive query time component, wherein the active query time component is directly required for querying, and wherein the passive query time component defines a pause between the end of the active querying of one network participant and the beginning of the active querying of the next network participant; comparing the determined cycle time with at least one initial request time concerning the network participants defined in the first application;Outputting information on whether the determined first cycle time exceeds at least one first request time or not, wherein, in the case that the first request is not met, the information includes at least one measure to reduce the first cycle time; where the passive query time of one or more of the network participants is reduced by starting the query of the next network participant earlier each time.

[0011] The method according to the invention is intended to verify whether sufficient time is available for the network participants to be queried, thus ensuring that the application's request time can be met. In this way, it can be ensured that the first application delivers reliable results, because, for example, a violation of the sampling theorem can be ruled out.

[0012] The first filter can be freely added to the Edge Device or the first application.

[0013] For example, the filter is contained in a file that can be loaded into the edge device and made accessible to the first application.

[0014] The application is, for example, a digital service defined at the outset.

[0015] According to an advantageous embodiment of the method according to the invention, at least one second application runs on the edge device, wherein the edge device additionally queries data from those network participants which are defined via a second filter accessible to the second application, wherein a second cycle time of the second application is additionally determined, wherein the second cycle time denotes the respective time interval between two queries of a network participant defined in the second application, wherein a total cycle time is calculated based on the first cycle time and the second cycle time, wherein the total cycle time is compared with at least one second request time concerning one or more of the network participants defined in the first application and / or second application, and wherein information is output as to whether the total cycle time exceeds the second request time or not.

[0016] Numerous additional applications can be configured to run on the edge device and access a separate filter that defines field devices for querying. Each of these additional applications defines a separate cycle time, which is added to the total cycle time.

[0017] According to a first variant of the inventive method, the second cycle time is determined by summing up a respective query time from each of the network participants defined in the second application, wherein each query time consists of an active query time component and a passive query time component.

[0018] The active query time refers to the portion of time required to obtain information from the relevant network participant and thus includes the time spent sending and transmitting the request, the time spent processing and creating the data by the network participant, and the time spent sending and transmitting the response.

[0019] The passive query time fraction refers to the portion of time that lies between receiving the response and the start of the query from the next network participant.

[0020] According to an advantageous embodiment of the first variant of the method according to the invention, the respective query time is determined by querying data from the respective participant via the edge device. When the request is sent to the corresponding network participant, a timer is started, which is only stopped when the request is sent to the next network participant. . Advantageously, a timestamp is set when the response arrives at the edge device in order to determine the active and passive query components.

[0021] According to an advantageous embodiment of the first variant of the method according to the invention, the respective query time is determined in advance, stored, and communicated to the edge device. The query times can be stored on an external database or on the edge device itself. This accelerates the process flow. It is possible to execute the process steps of the previous embodiment to determine and then store the respective cycle time, in particular including the active and passive query components. It is also possible to repeat and store the process steps of the previous embodiment regularly to ensure that the correct time values ​​are always available.

[0022] The database is preferably a cloud-enabled database, which is integrated on a server and can be accessed via the internet.

[0023] According to a second embodiment of the method according to the invention, the first cycle time and / or the second cycle time is determined by querying a network participant for the first time, querying all other network participants defined in the first application or in the second application, and measuring the time elapsed until the network participant is queried again as the first cycle time and / or second cycle time. According to an advantageous further development of the method according to the invention, if the determined first cycle time and / or the total cycle time is less than the at least one requirement, the respective information includes details of the available time until the at least one first requirement or second requirement is exceeded, and the respective information is obtained by additionally querying the data from the first filter or second requirement.The second filter is used to determine the defined network participant.

[0024] This situation is called the "best-case scenario", in which there is still potential for adding further network participants.

[0025] The information is advantageously made available to the database, or transmitted to the database.

[0026] According to an advantageous embodiment of the method according to the invention, the respective information contains a number of possible additional network participants of at least one device type, wherein an average query time is assigned to each device type, which is determined in particular by querying one of the network participants of this device type, the number being calculated based on the available time and the average query time. The user is thus informed of the number of network participants that are possible before a violation of the cycle time occurs.

[0027] According to an advantageous embodiment of the method according to the invention, if the second requirement is not met, the information includes at least one measure for reducing the overall cycle time. For example, the passive polling time component of one or more of the network participants can be reduced. It can be provided for this purpose to specify a maximum passive polling time component, so that the individual polling time component of at least one to all network participants is reduced to this maximum. The edge device can calculate this maximum passive polling time component based on the information about the individual network participants and their polling characteristics.

[0028] According to an advantageous embodiment of the method according to the invention, at least one of the network participants is a field device used in automation technology. During the query process, data is retrieved from the field devices, in particular physical measured values ​​of a process engineering operation, diagnostic data from the field devices, and / or status values ​​of the field devices.

[0029] According to an advantageous embodiment of the method according to the invention, at least one of the network participants is a control component or gateway. During querying, data from the control components or gateways is retrieved, in particular diagnostic data and / or status values, and / or, if field devices are connected to gateways, data from these field devices, in particular physical measured values ​​of a process engineering operation, diagnostic data, and / or status values.

[0030] Furthermore, the problem is solved by an edge device which is designed for use in the method according to the invention.

[0031] The invention is explained in more detail with reference to the following figure. It shows

[0032] Fig. 1: an embodiment of the method according to the invention.

[0033] In Fig. 1 The image shows an Edge Device ED. The Edge Device ED comprises operating electronics, stacks for executing multiple applications AP1, AP2, APn, and a communication module KB.

[0034] The edge device ED is connected to both a first communication network KN1 and a second communication network KN2. The first communication network is, for example, a fieldbus used in automation technology, to which several network participants are connected. These network participants are field devices FG1, FG2, FG3, and FG4, designed to acquire and influence physical parameters of a process. Examples of such field devices FG1, FG2, FG3, and FG4 are listed in the introductory section of this description. The network participants can also be control components or gateways GW1 and GW2. The first communication network KN1 can be divided into several segments SG1 and SG2, which may or may not use the same or different protocols.Gateways GW1 and GW2 serve, for example, as protocol conversion units between the different segments SG1 and SG2. All common fieldbus protocols, such as HART, Profibus PA / DP, Foundation Fieldbus, and Ethernet protocols, can be used. It is also possible for some network participants to be remote I / Os that query the field devices, for example, via HART or AS / RS communication.

[0035] The edge device ED cyclically queries data from network participants, which is then made available to the application applications AP1, AP2, and APn for processing. The processed data is transmitted via a second communication network KN2, which is the internet, to a cloud-based database DB, for example, for asset management or device healthcare purposes.

[0036] Applications AP1, AP2, and APn are each provided with corresponding filters that define the network participants to be queried. Based on these filters, applications AP1, AP2, and APn inform the communication block KB of the network participants to be queried. The communication block KB then queries the corresponding network participants cyclically. A specific query time is allocated for each network participant. This query time consists of an active query time component, which is directly required for the query, and a passive query time component, which defines the pause between the end of the active query of one network participant and the beginning of the active query of the next.With a large number of network participants to be queried, the sampling theorem may be violated, leading to errors in highly dynamic measurement curves, for example, if peaks occur in the measured values ​​between two queries.

[0037] To verify that the requirements are still being met, a cycle time is determined. The cycle time is defined as the time that elapses until one of the network participants is queried again, or more precisely, until the same variable, the same type of value, etc., is queried again. This can be determined either by having the edge device query the respective participant's data, or by having the respective query time determined in advance and read from a database by the edge device.

[0038] This cycle time is compared to the request time of the first application. The request time is a so-called "configured" cycle time and is dimensioned such that all defined network participants can be accessed and the sampling theorem is not violated, so that a measurement curve can be transmitted without errors.

[0039] If the cycle time is shorter than the request time, the user is notified as a "good case." Subsequently, additional network participants can be added. The edge device calculates, or displays, to the user how many more network participants can be added until the request time is just within the limit. For this purpose, a so-called available time is determined. This available time is calculated from the difference between the request time and the determined cycle time. Knowing the time of a network participant, the time of all remaining available network participants of that type can be calculated.

[0040] If the request time is exceeded, the user is notified as a "bad case". The user is also informed of a measure to reduce the cycle time. For example, the passive query time of individual network participants can be reduced by starting the next query earlier.

[0041] It may be possible for each application to define multiple network participants to be queried using appropriate filters. A total cycle time is calculated, which must not exceed the respective request times of each application. To reduce the total cycle time, it may be possible to shift the queries of each application into a sequence, for example, by dividing them into sufficiently large periods of passive query time, thereby significantly reducing the overall cycle time.

[0042] The method according to the invention is carried out in particular after the initial configuration of an edge device ED in order to quickly provide feedback as to whether the edge device ED can query the desired network participants. Advantageously, the method is also carried out after exchanging or adding network participants. Reference symbol list

[0043] AP1, AP2, APn Applications DB Database EDEdge Device FG1, FG2, FG3, FG4 Field devices, Network participants GW1, GW2 Gateways, Network participants KB Communication module KN1, KN2 Communication networks

Claims

1. A method for diagnosing the operation of an edge device (ED), wherein the edge device (ED) is in communication connection with a plurality of network participants (FG1, FG2, FG3, FG4, GW1, GW2) via one or more communication networks (KN1), wherein the edge device (ED) is in communication connection with a database (DB) via a further communication network (KN2), wherein at least a first application (AP1) is running on the edge device (ED), and wherein the edge device (ED) queries data of those network participants (FG1, FG2, ..., GW2) that are defined via a first filter accessible to the first application (AP1), the method comprising: • Determining a first cycle time of the first application (AP1), the first cycle time specifying the respective time period between two queries of a network participant defined in the first application (AP1); wherein the first cycle time is determined by summing up a respective query time of each individual network participant (FG1, FG2, ..., GW2) defined in the first application (AP1), each query time consisting of an active query time portion and a passive query time portion, the active query time portion being required directly for querying, and the passive query time portion defining a pause between the end of the active querying of one network participant (FG1, FG2, ..., GW2) and the start of the active querying of the next network participant (FG1, FG2, ..., GW2); • Comparing the determined cycle time with at least a first requirement time relating to the network participants (FG1, FG2, ..., GW2) defined in the first application (AP1); • Outputting information as to whether the determined first cycle time exceeds the at least one first requirement time or not, wherein, in the event that the first requirement is not met, the information includes at least one measure for reducing the first cycle time, wherein the passive query time portion of one or more of the network participants is reduced by starting the query of the next network participant earlier in each case.

2. The method according to claim 1, wherein at least a second application (AP2) is running on the edge device (ED), wherein the edge device (ED) additionally queries data of those network participants (FG1, FG2, ..., GW2) that are defined via a second filter accessible to the second application (AP2), wherein additionally a second cycle time of the second application (AP2) is determined, the second cycle time specifying the respective time period between two queries of a network participant defined in the second application (AP2), wherein a total cycle time is calculated based on the first cycle time and the second cycle time, wherein the total cycle time is compared to at least a second requirement time relating to one or more of the network participants (FG1, FG2, ..., GW2) defined in the first application (AP1) and / or the second application (AP2), and wherein information is output indicating whether the total cycle time exceeds the second requirement time or not.

3. The method according to claim 2, wherein the second cycle time is determined by summing up a respective query time of each individual network participant (FG1, FG2, ..., GW2) defined in the second application (AP2).

4. The method according to claim 3, wherein the respective query time is determined by querying data of the respective participant by the edge device (ED).

5. The method according to claim 3, wherein the respective query time is determined in advance, stored, and made accessible to the edge device (ED).

6. The method according to claim 1 or 2, wherein the first cycle time and / or the second cycle time is determined such that a network participant (FG1, FG2, ..., GW2) is queried for the first time, all further network participants (FG1, FG2, ..., GW2) defined in the first application (AP1) or in the second application (AP2) are queried, and that time is measured as the first cycle time and / or the second cycle time which elapses until the network participant (FG1, FG2, ..., GW2) is queried again.

7. The method according to at least one of the preceding claims, wherein in the event that the determined first cycle time and / or the total cycle time falls below the at least one requirement, the respective information contains details of the available time until the at least one first requirement, or respectively second requirement, is exceeded, and wherein the respective information is determined by additionally querying the network participants (FG1, FG2, ..., GW2) defined by the first filter or respectively by the second filter via the edge device (ED).

8. The method according to claim 7, wherein the respective information comprises a number of possible additional network participants (FG1, FG2, ..., GW2) of at least one device type, wherein an average query time is assigned to a device type, which is in particular determined by querying one of the network participants (FG1, FG2, ..., GW2) of this device type, wherein the number is calculated based on the available time and the average query time.

9. The method according to at least one of the preceding claims, wherein at least one part of the network participants (FG1, FG2, ..., GW2) comprises field devices of automation technology.

10. The method according to at least one of the preceding claims, wherein at least one part of the network participants (FG1, FG2, ..., GW2) comprises control components or gateways.

11. An edge device (ED) configured for use in a method according to at least one of claims 1 to 10.