Motion Control Protocols

What faces communication protocols in motion control?

Certainly Sercos and Profibus are interesting because the next generation is going to be the Ethernet solutions. The Ethernet solutions on Sercos are going to continue to adopt the same protocol that they utilized on earlier versions of the network solution. Sercos originally was the fiber-optic specialized networking solution for motion. Now with Ethernet it will allow it to use more commercially available hardware. But they are retaining the existing protocol layer so a lot of the application layer will be relatively the same. The same thing is true on Profibus. By 2000, they implemented a motion control capability in the standard Profibus communication link that uses RS-485. Now, with the next generation, it is going to be PROFInet IRT for Isochronous Real Time.

What is the timing of these?

They have already been announced but there won't be availability until probably 2005 or 2006. You will see some beta products at the SPS show in November.

What about FireWire?

If you're going to be a power and motor player today, you have to be willing to support almost any interface out in the market-whether it's Sercos, FireWire, Ethernet, or some of the newer Ethernet solutions such as SynqNet. It's almost going to be a requirement. You are going to support a variety of interfaces. Otherwise, you are going to find yourself boxed out.

Does FireWire itself provide anything special that is allowing it to take off?

There is no indication now that FireWire is taking off. There was a lot of talk about it around 1999, and pretty much it never materialized. There are a number of competitors that have it today. What I think is that Ethernet introductions started and really killed the notion of going to FireWire. People do not want multiple technologies anymore. Ethernet is obviously going to connect to high-level controls, the other part of the automation system, and even I/O. There doesn't seem to be a lot of momentum behind FireWire anymore. It's a niche application. We do see some applications where they are trying to integrate motion and I/O together.

You mentioned SynqNet. What is SynqNet?

That's another commercially available solution that uses Ethernet components with its own protocol. What it's going to shoot for is very high-performance applications. It is one of the more higher performance solutions around for motion control and they put I/O on the bus. What we are starting to see is the convergence of some I/O on the motion control bus because the bus is increasingly getting higher performance; people want to have machines with a single bus structure so they also want to bring the I/O and motion together on a single bus-within certain constraints.