As U.S. manufacturing and production moves toward what is generally considered the fourth Industrial Revolution, popularized as “Industry 4.0,” many of the necessary technological components are already in place. However, there is some additional ground that must be covered. A consensus is forming around the notion that the primary component preventing the revolution from reaching full speed is wider acceptance of communication standards. So how can we consistently, and with less effort, exchange data between the various components of a highly connected industrial machine or process?
Many automation professionals have grown too used to the idea that communicating between devices and vendors is difficult, due to deliberately built-in roadblocks. Unfortunately, some have just accepted that each installation requires a significant integration effort to establish communication within the system and with external networks and databases. Too often, establishing the levels of connectivity expected by today’s global enterprises requires great amounts of talent, time, and expense. Without better adherence to standards, system integration for highly connected solutions will continue to be a complex challenge.
As a colleague of mine put it recently, we are dealing with “thousands of one-man bands.” As such, standards are necessary to accomplish two things:
- a common look and feel
- a consistent communications interface
There is light at the end of the tunnel, however—industrial control systems are quickly leaving their history of isolation and segmentation with regard to information and control. Increases in connectedness are becoming a requisite, rather than a luxury, and this connectedness is more fluid, offering faster, simpler implementation. The industry could use more of a Steve Jobs-ian, “it just works” mentality (Steve Jobs famously quipped, “it just works” during several iPhone launches).
For the U.S. manufacturing industry to prosper in the future, we must create systems that can adapt quickly and easily. It has to “just work.” This will raise efficiency, reduce time to market, and be more flexible for vendors and end users. True progress must improve the competitive outlook of the machine user, as well as the machine builder. Open communication standards, not a vendor-specific protocol or method, can make this progress happen for all parties, with the added benefit of simplifying system designs.
The good news is that many of the required standards already exist and have existed for some time. When fully embraced, these can be of great benefit to the automation community. Specifically, we can look at the packaging industry, a well-known hotbed of technological innovation. Packaging equipment must deal with high speeds, multi-axis motion control, advanced vision systems, and the frequent involvement of several different vendors in one installation. Too often, there is little communication between the machine modules, as manufacturers tend to treat each segment individually. The unique aspects of each piece must be kept in mind, often requiring specialists.
What if we agreed on mechanisms to share information, with names that are both useful and consistent? What if we agreed on a standard way of handling individual machine states? The answer to these questions is a standard that has been available and implemented by leading companies for years. This technology, Packaging Machine Language (PackML), is a powerful communications language developed over the past 15 years, primarily through the efforts of the ISA88 committee and the Organization for Machine Automation and Control. Recently, Packaging Machinery Manufacturers Institute has taken over the development and maintenance of the language. PackML is known officially as ISA-TR88.00.02-2008 (v3.0 released in 2008); an updated 2014 version of the technical report is currently being voted upon by the ISA88 committee. Combined with the ISA-88 Part 5 standard currently in development by ISA88, PackML provides a consistent architecture and approach to machine programming geared toward, but not limited to, the packaging industry. PackML is growing in prominence within the packaging industry. The third revision has found wide use; Proctor & Gamble is a high-profile example. Proctor & Gamble went so far as to publish and promote a PackML implementation guide in 2009.
PackML provides two key components for our use: a state machine and a set of tags called PackTags, used as a communications interface. A well-planned communications interface is important for feature-filled, multitasking devices, such as the one in smartphones. The information exchange between the GPS unit, the dialer, the Wi-Fi connection, and the various sensors on the phone is channeled through a set of interfaces that are well designed, well named, and easy to implement and use. The success and pervasiveness of modern smartphone technology cannot be denied, providing ample evidence that a similar communications interface for industrial machinery should be seriously considered.
So how does a PackML state machine relate to this, and how can it be of use to the manufacturers and users of packaging machinery? The primary use of a state machine is not so much for normal operation; it is a powerful mechanism for production problems and dealing with exceptions. In addition, a state machine with a common look and feel benefits both the developer and the end user. An operator can look at any part of the machine and have an instantly familiar human-machine interface screen that displays relevant information in a simple, universally accepted format. The machine builder benefits, because the structure does not have to be designed from scratch.
With the right technical specifications and with manufacturer support, PackML is the leading candidate for a standard to interface packaging systems, with the hope of getting packaging machines to that smartphone level of user friendliness. Today’s PackML users already have a common look and feel, as well as agreed upon methods to exchange data in the control system that are vendor-agnostic. Like the initiatives of PLCopen, the forces behind PackML seek a commonality in appearance and in functionality between different vendors. This way, the operator can walk up to any machine, look at the display screen, and see a familiar interface. This helps the operator avoid the learning curve associated with new machinery.