Implementation de ECAT dans LabVIEW pour un controle de carte EPOS

[stephaneLET]

Bonjour à tous,

Je suis en train de tenter d'établir une communication entre LabVIEW et une carte EPOS4 via EtherCAT. J'ai rencontré que des problemes.

Petit résumé des trucs déjà tenter:

J'ai installé les pilotes NI-Industrial Communications for EtherCAT, en veillant à la compatibilité avec ma version de LabVIEW et mon système d'exploitation (Windows 64 bits).(https://www.ni.com/fr/support/downloads/tools-network/download.ethercat-library-for-labview.html?srs...)

J'ai également installé les outils de configuration spécifiques à EPOS4, fournis par le fabricant.(https://forums.ni.com/ni/attachments/ni/170/1106848/3/EPOS-LabVIEW-Instrument-Driver-En.zip)

J'ai suivi attentivement les instructions de configuration du réseau EtherCAT, en m'assurant que les paramètres réseau étaient corrects.

J'ai importé les fichiers ESI correspondants aux cartes EPOS4 dans LabVIEW.

J'ai pris soin de vérifier la compatibilité des versions de LabVIEW, des pilotes et des cartes EPOS4.Mais jamais rien , impossible d’acceder a la biblio eCAT dans labview

Malgré ces étapes, quand j'essaye de rechercher les fonctions concernant Ethercat dans labview, aucun résultat.  La documentation et les exemples fournis ne sont pas super precis et sont souvent de 2011 ou 2016. Je me demande si quelqu'un a déjà rencontré des problèmes similaires avec l'intégration de cartes EPOS4 en EtherCAT dans LabVIEW. Toute aide, conseil ou exemple de projet serait extrêmement apprécié.

Merci d'avance pour votre aide.

[rolfk · Accepted solution]

Well I never tried to control EPOS drives through EtherCAT.

Also EtherCAT is less than ideal to use under LabVIEW. Beckhoff traditionally wasn't very fond of LabVIEW and did little to support it in the past and NI lost interest in EtherCAT somewhere between 2016 and 2019.

It doesn't help that you seem to be mixing and matching various drivers in your attempts. LabVIEW Industrial Communication Toolkit for EtherCAT is a National Instruments driver Toolkit that in itself is self contained. It can do a lot but its documentation is lacking and NI people had even back in the day when they were still actively supporting it, usually trouble to provide much helpful support if things were going beyond the standard device functionality. Configuration of the EtherCAT system through network enumeration could be tricky and configuration through the classical ESI files was limited as the NI tools did not always understand all possible configuration file elements.

The other software you mention is a completely different and independent EtherCAT master library from Ackermann Engineering. It provides at least under Windows a similar functionality than the NI Toolkit, but both products have absolutely nothing to do with each other, besides providing EtherCAT master functionality. And the latest version of that is indeed from 2015. Mister Ackermann has in the meantime moved from Germany to the sunny Spain and while he still seems to do some business, I'm not sure how active he is in supporting this library.

And both libraries are not free to use but require an actual paid license.

[stephaneLET]

Thanks for the clarification, Rolf.

You're right—after spending quite some time trying to make it work natively in LabVIEW, it’s clear that the EtherCAT support is not only limited but also fragmented between incompatible toolkits.

At this point, considering the constraints and lack of up-to-date documentation, I believe the most straightforward and maintainable solution is to develop a separate DLL specifically for handling EtherCAT communication, using a dedicated EtherCAT master library outside of LabVIEW.

This DLL can then be interfaced with LabVIEW using the "Call Library Function Node", which gives us the flexibility to manage the communication properly, while still keeping LabVIEW for high-level logic and UI.

If others have followed this path or have any experience to share with this approach, I’d be happy to hear about it.

Thanks again for your detailed input.

Stéphane L

[rolfk · Accepted solution]

I haven't really done much besides a bit twiddling with the idea. EtherCAT is complicated. First, you can't sell a solution that contains EtherCAT without obtaining a license from the EtherCAT consortium, aka Beckhoff, although this license is in principle free for master implementations.

As to existing code libraries it's also not straightforward. There are commercial parties selling their own libraries, either in source code or binary form. They aren't exactly cheap though. Then there is the source code that you get supposedly access to as a paying member of the EtherCAT consortium. That's a yearly membership fee which isn't exorbitant for a business but still a considerable reoccurring fee. Last but not least you have SOEM, an open source library but it is under GPL license. If you use that in your product you legally make your entire application GPL licensed too, with the obligation to open source everything. Not really something I and many others would be prepared to do.