Dear Expert,

I'm a student working on my thesis project and I have a question about the PROFINET wireless communication, and if it would be a (best?) solution to my problem.

I am currently conceptualising a automatic assembly machine with a lot of moving parts, specifically a rotating turret containing most of the actuators. To avoid wires in and out of the turret is one of the main problems I am dealing with now, and as such my question is as follows;

Is the wireless PROFINET capable of sending data trough rotating metal bars? I envision a system where most calculations are done in a static Master controller, and the data send wireless to the various slaves rotating along with the turret.
The turret itself would be rotating rather fast, say 60 RPM or more, so parts of the construction would be flashing in front of the transmitter continuously.

I hope you can shed some light on this matter, or maybe recommend another form of data transfer that would solve my problem.

Thanks in advance,

Leo

Hi,

Can you provide some more information like 

1.which master cpu you're using??

2.which io you're using for slaves ,how many number of slaves are there in  your config??

3.what is the maximum distance from master to slave (if possible explain it in a picture)??

yes the wireless system is capable of sending data through metal..

Hi Leo, 

please provide a draft of your building. Including some measurement values.

You can use WLAN for sending PROFINET frames. Therefore SIEMENS has the proprietary protocol iPCF which is capable of realising deterministic  WLAN communication, fast roaming, ...

So the only question is the illumination between your controller and the decentrale Periphery (DP) and your requirements: how fast has your IO cycle to be? 

my questions: how thick are your rotating metal bars? how is the paritioning betweend air and metal?

and as already asked: which components are you using in the middle? some ET 200-stations? or some PLCs? and again: what is your required update time?

one nice thing to read for you:

RCoax manual (RCoax is a special antenna to communicate in near field. makes the wireless communication more stable and allows lower update times)

Leo Loco

Is the wireless PROFINET capable of sending data trough rotating metal 

 pure metal reflects the signals. so you need some air between the metal.

perhaps it is also posssible to place the antennas above the metal construction and get your signal to the DP from there!? (as i said: perhaps send a draft)

Hi,

Thanks for the replies!

Unfortunately I am unable to share drawings or specific information at this time, as there are none yet. To give some more insight, I am still very much evaluating possible options, and defining problems to solve the main question of my research. The main reason for posting here and consider the use of Siemens products is because they are the preferred platform of the company I'm working at. 
My personal experience with PLC systems is (unfortunately) non existent at this moment, In college they taught me how to build a digital system with PLC functionality, but never bothered taking it into practice...

Which makes this a perfect learning opportunity! And not to make my work harder then it needs to be I hope to draw upon the local knowledge of the system here.

The main focus of my research is conceptualising a continuous motion assembly machine, using servomotors and digital control over the more common mechanical relations seen in these kinds of machines. Thus the soft- and hard-ware take the blunt of the design. Adding to this that where a mechanical design would be self controlling trough its form and function, I am dealing with a lot of control loops, actuators, inputs for feedback, and all the wires that come along with those.

This poses a number of problems of which I assume I don't oversee nearly half at this moment, but I'm determined to tackle these problems step by step.
To add to this, the design is very much up in the air at this point, requirements have been set for function, form is up to me.
On the notion of time, this system has to be fast, requirement is to produce 300 parts per minute, with an assembly procedure of 3 steps, and quality controls after each step. To this end I have assumed to take 5 assembly stations, and rotate them at 60RPM, resulting in the required 300 parts handled per minute.

As I'm still scavenging for information to make calculated design decisions, this could also very well change down the road, but its a start...
As most actuators will be positioned in the turret, I'm thinking X, Y, and Z positioning for each tooling station at the least, I hope to incorporate much of the control system inside the turret, to avoid entangling wires. However connection to the outside world will need to be maintained, if only for the interface module. (try to read a display rotating 60 rpm in front of you, the idea cracks me up).

On the notion of scale, in total I don't envision the system to be any larger then a standard continuous motion machine, or automatic assembly machine for that matter. But, that doesn't mean anything without measurements...which I don't have at this time. Yet this also gives me the freedom to take your suggestions into consideration without drawback, elevating the antenna's above the machine for example was something that hadn't occurred to me yet (for some reason).

I do envision the end result to somehow resemble the turret of a battle tank, actuators 'on top' and the support for those systems below the table, rotating along with the actuators.

And with that, thank you very much for the information, and I hope to at least have shed some light on the project and where I'm coming from.

Cheers,

Leo

New question published by AutoGen_1041985 is split to a separate thread with the subject Wireless PROFINET with Lotus.

Best regards
Min_Moderator