More than 70% of all respondents to a recent survey said that motion and logic should be integrated into the same control platform on modern packaging equipment. Further, another 52% believed that the motion controller will replace the PLC for packaging equipment controlled by a single controller that handles motion and logic. Funded by Rexroth Indramat (Hoffman Estates, IL), the survey was conducted for the Motion for Packaging Working Group of the Open Modular Architecture Controls (OMAC) users group. Conducted via the Packworld.com Web site March through June 2000, the invitation-only survey consisted of mostly packaging end users, though it included some machinery builders. While it’s not a statistical representation of the industry as a whole, the survey does give a back-of-the-napkin sketch of the way many packaging end users view motion control and networking issues related to packaging machinery. The survey found that Ethernet, a common networking protocol, seems to dominate packaging machine networking. Two-thirds of respondents are planning on Ethernet for the interface from machine controllers to supervisory/enterprise systems. And almost as many (60%) plan on using Ethernet for machine-to-machine (also known as peer-to-peer) networking. Nearly a third are using it already. When asked which protocol would be implemented over Ethernet, the winner was hyper-text transfer protocol (HTTP), the same protocol used on the World Wide Web, with more than a 40% response. (For industrial networking, a secondary protocol is typically required on top of Ethernet.) Next came DeviceNet (35%), ControlNet (26%), with the remainder splintered among a number of other protocols. Surprisingly, 44% of respondents are planning on using Ethernet for an I/O network, sometimes referred to as a fieldbus or device-level network, within a packaging machine.
No motion standard Amongst survey respondents, there really is no dominant protocol for motion control. Most respondents (50%) are still using analog drives and controllers. The rest are fairly evenly fragmented among varying open and proprietary bus protocols. However, this will change: Nearly half of respondents (48%) said they have plans to switch from analog to digital motion control networks. More than 40% either use or are considering using Ethernet as a motion network, followed by SERCOS (an open motion control network protocol) at 29%. And a quarter of respondents plan to test FireWire, which is a high-speed open protocol. A significant number (30%) plan to use whatever their machinery builder or controls supplier recommends. Based on two other questions in the survey, a majority of respondents agreed that two reasons for using open architecture controls include the ability to deliver better information to enterprise resource planning (ERP) systems from the packaging line, and to reduce dependence on any given controls vendor. A detailed presentation on these survey results, delivered by Grant Jacoby’s John Kowal at the recent Pack Expo OMAC meeting, is available on the OMAC Web site at www.arcweb.com/omac. More information on the OMAC packaging working group is available at packworld.com/go/omac.
