What Control Engineers Should Know About Industry 4.0

Control engineering is a well-established discipline with a long and prominent history. It is diverse in its applications but has a strong unifying core to it: the notion of dynamic systems and control theory. Many engineers will have encountered it as part of their education, as control engineering courses are taught to electrical, mechanical, chemical, aerospace, and industrial engineers. Quite often, though, this is the only time that engineers consciously encounter the subject of control systems.

While control engineering is rooted in mathematical theory and tools, Industry 4.0 relies on a variety of technologies. Industry 4.0 is a new and still-evolving paradigm in which digitalization is expected to revolutionize industry and core technologies are still emerging. The term was coined in 2011 by a German government taskforce and has been adopted by the World Economic Forum (WEF)ii. Its concepts are known to engineers, corporate managers and policy makers, but it can be difficult to grasp and define. 

In this article, we address the intersection of control engineering and Industry 4.0 by examining the underlying methods and technologies as well as one vertical industry—steelmaking—so readers can discover how control engineering is helping to drive the development of this new production era of Industry 4.0. 

History and definitions 

Industry 4.0, the fourth industrial revolution, is now roughly 10 years old and there is increasing agreement and clearer definitions of what it comprises. The first three industrial revolutions had concrete drivers: mechanization, electrification and the advent of computers. Industry 4.0 has no single technology association; several technological advances and design principles drive it. Its underlying principle is digitalization.

Originally, there were nine pillars or technologies on which the vision of Industry 4.0 relied. These technologies have been adaptediii somewhat but the originals introduced in 2011 include: simulation; cyber-physical systems (a computer system in which a mechanism is controlled or monitored by computer-based algorithmiv); robotics; and artificial intelligence (AI), big data and data analytics. 

So why is control not listed as one of the important technologies of Industry 4.0? One answer is that control engineering itself could have been singled out as a technological driver because control is one aspect of most—if not all—pillars. Another reason is that control engineering and Industry 4.0 terms overlap but address different functions in different applications.

As shown in Figure 1, control engineering relies on several—mostly mathematical—tools and techniques such as system analysis, state estimation and modeling and simulation to perform different types of control including optimal, adaptive, linear, non-linear and intelligent. Similarly, Industry 4.0 uses its core technologies and techniques to enable new technologies that can be applied to manufacturing and industrial processes as well as consumer products, financial services and more.

With simulation used by both control engineering and Industry 4.0, and one could easily jump to the conclusion that this is the most obvious intersection of the two areas. But the truth is more complex. The different mathematical models that underlie a simulation need to be distinguished. Are they dynamic models relating to the driving of a vehicle? Are they modelling the body of a car? The first concerns control engineering, the second does not. 

The narrow aspect of individual control strategies separates them from the broad application of new Industry 4.0-related technologies like Internet of Things, augmented reality, 5G/cloud computing and the rest. In fact, unlike control engineering, Industry 4.0 has gained so much traction that it has entered the consciousness of the general public. As the new technologies’ spawn are applied to more than just industrial production, the term has grown beyond its original definition.  

For example, a cell phone app that allows you to book an apartment in your city or autonomous robots delivering food or packages is not an example of the latest industrial revolution. But their developers are using the Industry 4.0 technologies to enable them. Simulation, robotics and AI/data analytics are being not just to produce smart phone or delivery robots, but they are being used within manufactured products.  

On that point, Industry 4.0 is similar to control engineering. In the automobile industry, for example, Industry 4.0 technologies and concepts affect the actual manufacture and assembly of cars. But “control engineering” in the automotive industry often concerns the development of algorithms for speed control, shock absorption and so on within the car—which is not necessarily related to the production of the vehicles. 

It is impossible to list all the applications of control in every Industry 4.0 technology. The reason is not only the fuzzy nature of Industry 4.0 definitions, but also the complex structure of modern production technology and the different applications of control specific to different vertical industries. So here we will examine one metals industry example for which control engineering is crucial: steelmaking.