Hi everyone,

I am currently trying to work with an app (AI Inference Server) on an Edge Device. This app takes an input (e.g. from the IE Databus), calculates with the data, and produces an result output, which I want to write back to the IE Databus in order to plot the result in another app like Performance Insight.

I am facing two problems, for which I can't find any solution in documentation:

When the AI Inference Server app imports data from the IE Databus, I can't "browse" for variable tags, so I have to specify the exact path at which the variable is stored in the IE Databus (something like "ie/d/j/simatic/v1/opcuac1/dp/r/myPLC/default/TARGET_VARIABLE"). I know the whole path from the IE Databus Configuator "Live View" functionality, but am missing the last part which I called "TARGET_VARIABLE" in this example. So where can I find information about that?

The second problem I have:

Interestingly, I can run the AI Inference Server app by specifiying the variable path to "ie/d/j/simatic/v1/opcuac1/dp/r/myPLC/default", but I assume that in this case all variables get imported randomly, so no useful result is produced. However, something is produced and I have already managed to publish these "results" to the IE Databus. At least I assume it works because in the IE Databus configurator "Live View" the path to where I wrote to result is marked green. But then, I don't know how to proceed in order to make this result data available in another app like Performance Insight. I tried to add the respective variable in the Data Service app but it is not available. So what is the procedure in this case?

I am really looking forward to your answer, thanks in advance!

Hello LorenzFehn,

can you tell me which version of the Ai Inference Server are you using? 
Did you follow one of the tutorials described here:

AI SDK - Project Templates

Vision AI on Inference Server

This should give you a basic understanding how this works.

A detailed description of the interface to the databbus can be found in the manual:

Industrial AI AI Inference Server in Chapter 4

The "TARGET_VARIABLE" is defined by yourself when configuring the connector you are using.

DobeHe

HelloLorenzFehn,

1. You can browse tags only from S7 Connector because it's providing meta data information on the data bus. It's documented in the user manual , release notesand alsopart of the UI as info tip

2. You must assign the different tags for different variables, there is no "random" import. Please note that it's possible to enter a variable path which does notexistas you wrote. It's mentioned in the user manual & release notes as known issue / limitation.

As for writing back to data service the data needs to be structured in the common data load format and can then be added to the data-service as custom adapter and in turn displayed in performance insight

Here are some useful links:

https://docs.eu1.edge.siemens.cloud/intro/build_your_use_case/data-processing/databus/reference/index.html

OPCUA:

https://github.com/industrial-edge/opc-ua-application-getting-started

Additional Example:

https://github.com/industrial-edge/common-databus-payload-format

Hope this helps, Have a nice day