October 8, 2013 saw the official launch of the joint research project plCASSO. The underlying aim is to tap into efficiency gains through the flexible provision of control technology for cyber-physical systems in industrial production. The existing monolithic control technology is to be broken up, modularized and expanded with cloud computing mechanisms such as central data processing and service-oriented software architectures.

The project partners took the official conclusion of the project on December 31, 2016 as an opportunity to report on the results achieved to date by plCASSO as part of the 'Stuttgart Innovation Days'. Around 150 participants came to the congress event organized by the Institute for Control Engineering of Machine Tools and Manufacturing Units (ISW) at the University of Stuttgart together with the Fraunhofer IPK in the state capital of Baden-Württemberg at the end of January.

In addition to the presentations, congress participants were able to see various live demos of plCASSO sub-projects on the ISW premises.

© ISW

One question that was repeatedly discussed in the various presentations was: Can cloud technologies really meet the requirements placed on industrial control systems? The unanimous answer was: Yes - but! Manufacturers such as Bosch Rexroth, Beckhoff and Kuka are working together with machine builders such as Homag to bring PLC, CNC and robot control functions into the cloud; however, if - as required in many industrial applications - the aspects of real-time or determinism play a role, there are clear limits due to the Internet-based communication networks: For example, the companies Robomotion and Sotec have determined round-trip times well into the double-digit millisecond range as part of a joint project involving the complete relocation of an existing Codesys control kernel to the public cloud. Against this backdrop, Heinrich Munz, Lead Architect Industry 4.0 at Kuka, expresses what most congress participants agree on: "In my opinion, a PLC - at least for the foreseeable future - does not belong in the cloud, but in the edge - in other words, in a machine-oriented component that 'buffers' the real-time and makes use of cloud services upwards!"

Keyword services: Even if the actual control core will probably remain at the 'place of action' for a long time to come, control-related (value-added) services can already be processed or offered via the cloud. The woodworking machine manufacturer Homag, for example, is already working on outsourcing complex computing services such as collision control or the actual NC program generation from the computer on the machine to the cloud. Heinrich Munz takes his thoughts even further in this direction: "Our customers don't primarily want to buy a robot, but the movement - so why not sell them just this in the future - keyword 'robot as a service'."

One thing is clear if these ideas are to become reality: automation technology manufacturers, and machine builders in particular, will have to focus heavily on software in the future. Or as Heinrich Munz drastically puts it: "The machine builders of the future will be software houses with a 'mechanics shop' attached - those who do not recognize this will not be successful!" And there is another aspect that is important to the Kuka visionary in all the discussions about the cloud: "If we are not careful, we will have to deal with 15 Internet protocols in the future - nobody wants that! What we need in automation is OPC UA and AMQP at the 'top' and Ethernet TSN at the 'bottom' - and nothing else!" It is up to the machine builders themselves to demand this one protocol variant from the providers.