From the very beginning when Henry Ford invented the first entirely human powered automotive assembly line for his Model T, the ongoing quest for better processes and ways to automate factories has been the goal. While Henry could never imagine the automation systems we take for granted today, he and his contemporaries like Karl Benz of Mercedes Benz were continually looking to streamline and improve the process of building automobiles. As electronics and the use of computers in control systems became the norm, factory floors and control rooms have become robotic and sophisticated marvels as they continue to evolve towards the future.
Today, we are able to automate and increase productivity far beyond the capabilities of the early pioneers utilizing modern developments of the computer and microprocessor age that includes programmable logic controllers (PLC), distributed control systems (DCS), human machine interfaces (HMI) and a huge variety of actuators, sensors, displays, lasers and other sophisticated technology that has transpired since those early factory days.
Before the assembly line, only the wealthy could afford an automobile. Henry Ford was responsible for dramatically lowering the manufacturing price of automobiles and his early efforts helped to lay the foundation of our industrial automation systems of today. These processes and technology have evolved to the point that not only the automobile has become a common product for the masses, but almost all products sectors have become within reach of the average citizen.
The First Computer Based Industrial Control System
The first industrial computer control system used in a factory was assembled in 1959 at Texaco’s Port Arthur, Texas refinery. This initial foray into the first industrial computer-based control system utilized a Ramo-Wooldridge Company model RW-300 computer. This computer was specifically designed as a control system computer. The RW-300 sported a state-of-the-art magnetic drum memory system. After the successful deployment at Texaco, they sold this system to various companies with their focus on promoting the system in the electric power station and nuclear power plant control arena. The Ramo-Wooldridge Company created additional advanced process control computers but got out of the commercial marketing of computers about the same time as they changed their name to TRW Inc. in 1965.
Minicomputer Based Systems
Industrial automation systems of today have their roots in the late 1960s and early 1970s as minicomputer based controls became more prevalent. As central control rooms with their huge and complex analog relays, wire looms and control panels gave way to centralized computer mainframe control rooms, industrial automation began to see the benefit of computerization.
As the Minicomputers came on the scene in the mid-60s and early 70s, the large mainframes of the late 50s and 60s started to slowly disappear from factories in favor of more distributed control systems. These distributed systems were being developed in the late 1960s but not perfected until the early 1970s.
The IBM 1800 was an early minicomputer that had input/output hardware to gather process signals in a plant.
Distributed Control Systems (DCS)
Distributed control systems for the most part took off due to the increased availability of microcomputers and the abundance of microprocessors in the world of process control. Larger minicomputer based systems had already been used for process automation prior to the microprocessor phenomenon mostly in what was considered direct digital control (DDC) and set point control.
The pioneering technology of distributed control systems (DCS) was the brainchild of engineers at Honeywell and a Japanese company called Yokogawa, which actually successfully installed a working DCS system prior to Honeywell. Honeywell’s first commercially viable product was the Honeywell TDC 2000 introduced in 1975, with Yokogawa’s being the CENTUM in the same year. These systems were designed to integrated production control for petroleum refineries, petrochemical, chemical, pharmaceutical, food and beverages, paper and pulp, steel and non-ferrous metals, cement, power, gas, water and wastewater industries.
These systems were more distributed forms of control but not entirely a true distributed control system as we know today. The TDC 2000 still had large clusters of computer hardware in giant cabinets containing huge amounts of input/output equipment.
This advance in technology quickly brought substantial profits to the Honeywell with almost $100 million in revenue obtained in the first year alone. Besides Yologawa and Honeywell, other companies such as Taylor, Bailey and Foxboro jumped on the DCS bandwagon contributing to a new era in factory automation. Back in the 1970s distributed control systems were widely responsible for the fastest growing segment of business in the automation industry.
The PLC Revolution
Almost concurrent with the development of DCS systems came the programmable logic controller (PLC). Designed to replace less reliable and cumbersome relay logic, the PLC was designed initially to meet the continuously changing needs of the automobile industry. This industry demanded regular model changes and factory configurations that required an easier method of reconfiguration. The PLC met this need and helped to change and innovate both large and small industrial applications.
Prior to the advent of the PLC and DCS, yesteryears relay control systems encompassed huge walls of relays, terminal blocks and miles of wiring. They were troublesome, inflexible, lacked easy re-programmability, and were power hogs. The new technology of PLCs opened up a world of innovation and easy reconfiguration capabilities for factory automation. Relay control systems were difficult to troubleshoot and maintain exhibiting continuous problems due to dirty contracts and loose wires providing a nightmare scenario for control engineers and technicians. Complex system documentation was typically not updated properly and difficult to decipher. A saying was born amongst those responsible for maintaining and troubleshooting these systems as a result, “five hours to find it and five minutes to fix it.”
General Motors Specification
By 1968 one of the giants of the automotive industry had it with these troublesome relay control systems when a group of engineers at General Motors Corp, headed by Bill Stone delivered a paper detailing criteria for a standard machine controller at a Westinghouse conference. The specification for this new technology detailed the desires of GM to include the following: full logic capabilities, extending static circuits to 90% of the plant machines, a modular design to enable future expansion and ease of replacement, inline programming capability using ladder logic and the need to work continuously in a heavy industrial environment impervious to vibration, dirt, moisture and electromagnetism. These specifications were submitted to Allen-Bradley, Digital Equipment Corp, Century Detroit and Bedford Associates to come up with a solution.
The First PLCs
After entries from DEC, Allen Bradley and Bedford Associates were presented to GM, Bedford Associates, won out with its Modicon 084 programmable controller (PC) in 1969. Dick Morley and his team of engineers at Bedford ended up creating a new subsidiary at Bedford Associates called Modicon as a result of their success with the 084 in 1973 which addressed a lot of additional needs of the marketplace. With this success the parent company some tax issues called the dissolution of Bedford Associates and they simply became Modicon.
Allen-Bradley and other Companies Make their Move
Later in 1971, engineers at Allen-Bradley developed what they called the programmable logic controller (PLC). It included many improvements that they missed in their first model presented to GM in 1969 called the programmable matrix controller (PMC). The new Allen-Bradley PLC was named the Bulletin 1774 PLC and became highly successful in the automation market. The name PLC became the preferred industry as the acronym PC was more associated with the personal computer at the time.
The early 1970s witnessed the birth of the PLC model of factory automation and other companies joined-in with entries of their own. Some of the more well-known companies included General Electric, Industrial Solid State Controls and Square D.
Modicon and Allen-Bradley had their early leads in the industry and a new era of industrial PC and PLC automation was at hand.
Computers not trusted for Industrial Processes
Back in the early years, the acceptance of computerized controllers were difficult at best because of the perception at the time that computers were inherently failure prone to heat, vibration, dirty factory environments and software glitches. Operating systems were known to lock-up from time to time and be unreliable. Many factories were hesitant to put their processes in the hands of such new and untested technology. They also felt that a small box filled with microprocessors and software could not possibly replace a room full of cabinets filled with relays and miles of wire.
PLC Manufacturers Fight Back
A major effort was launched by the manufacturers to disassociate and realign the perspective that PLCs were run by computers. After all, while they were microcomputer based, they were in fact proprietary, specialized microcomputers that were designed from the start to be reliable, dedicated to their task and much less vulnerable to the ills of other computer systems of those days.
PLC Automation Company Changes
Bedford/Modicon was eventually purchased by Gould Electronics in 1977 and then to Schneider Electric in 1997. Allen-Bradley was purchased by Rockwell Automation in 1985 yet their products and software still wear the Allen-Bradley name.
Third Party Software Companies
In addition to the above concerns, factory engineers didn’t like the fact that these early PLCs needed to be programmed via a dedicated and proprietary hardware terminals that were very cumbersome and difficult to navigate and program PLCs.
Scott Zifferer the co-founder of a company called ICON Software and Neil Taylor, owner of Taylor Industrial Software worked on software that allowed for a general computer interface helping drive acceptance of the PLC model of industrial automation. Previously, huge drafting tables were required for layout and programming of ladder logic and no troubleshooting and documentation abilities existed for using the original terminals.
Scott was focused on Allen-Bradley PLCs while Neil specialized in Modicon. They both successfully developed general computer interfaces for programming and documentation that dramatically improved workflow and eventual acceptance of the PLC as replacements for walls of relay panels and/or centralized computer systems.
This new software changed everything; Industrial automation was on a path of dramatic growth. ICON eventually was purchased by Rockwell Automation in 1993 and Taylor Industrial Software was sold eventually to GE Fanuc. Today ever evolving and easily programmed and documented PLC systems are part of industrial automation.
The 80s and 90s
Industrial automation continued with a vibrant period of growth and innovation through the 80s and 90s with smaller and smaller PLCs being developed due to the evolution of semiconductor integration. True distributed, redundant and much smaller and easily scaled and systems with much greater reliability became the norm.
Distributed systems require highly reliable and fast digital communication methods as the distributed components must accurately talk to each other. The 80s witnessed the need for these distributed systems to become more open and interoperable in their communication.
Thanks to the Department of Defense, in the 80s, UNIX took over as the predominant standard with its TCP-IP network communication technology. Concurrently and during that period, manufacturers began to develop Ethernet based systems with their own proprietary protocol layers.
The 1980s saw the beginning of PLCs becoming integrated into the distributed control system (DCS) infrastructure.
Internet technology had a profound effect on industrial supervision and control with most human machine interface (HMI) devices becoming fully TCP/IP compatible.
As far as input/output devices, digital FieldBus technology took over for the sensor 4–20 milliamp analog communications medium.
The 90s observed a huge transition in the move from the UNIX operating systems to the Windows environment. Microsoft ruled with the desktop and server layer Object Linking and Embedding (OLE) standard. This lent itself perfectly to distributed process control systems. The standard “OLE for Process Control” or (OPC) was the result and became the industry standard connectivity method.
Commercial off the shelf (COTS) components and the large scale adoption of IT standards drove the 1990s evolutionary process. Through the 90s previously PLC focused COTS suppliers such as Rockwell Automation and Siemens were able to offer lower priced DCS systems. In the meantime, the traditional suppliers of DCS systems were feverishly working on integrating the concepts and functionality of both DCS and PLC standards that they called “Process Automation System” (PAS). This utilized the latest Communication and IEC Standards of the day.
The next evolutionary step of PAS technology is called Collaborative Process Automation Systems (CPAS). This new technology will continue to allow for process control but will also turn also serve as the primary source of manufacturing data and information for what is called collaborative manufacturing management (CMM) applications. This integrated approach takes place all in one dynamic environment.
Back to Centralized Systems and New Connectivity Dangers
Ironic as it may seem, the move away from distributed systems towards centralization systems at the plant level is now the norm. Along with this, wireless communication protocols and embedded servers directly implanted in DCS controllers are a reality in today’s factories. This introduces full wireless web access to the factory floor. The human machine interface (HMI) possibilities become much more flexible and remote with these innovations. Process control monitoring and even supervisory control are possible and readily available from many plant equipment manufacturers with remote computer and even smartphone accessibility now possible. This opens up the world to our factories and begs for additional layers of security to address potentially serious safety and process sabotage concerns as a result of unauthorized access.
Innovative Stagnation Period
The negative growth as a result of the ushering-in of the Great Recession of 2008 has brought about much stagnation over the last several years in the world of industrial automation. A vibrant and dynamic trade show known as ISA drew tens of thousands of attendees in days gone past. Unfortunately, this once transitional event that yearly featured evolving and exciting automation technology became more of a technical symposium for a period of time a few years back. ISA was drawing only a small vestige of its former glory days of the 80s and 90s.
Moving forward today
Luckily, today in 2015, with a renewed thrust of economic vitality, we are seeing innovative technological ideas once again, but with some measure of hesitation and watchfulness. Driving this trepid leap forward is an economy that is still not quite sure of its footing. Renewed capital investment in the latest innovations in factory automation are limited with restricted momentum in manufacturing growth.