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Computers and the network are widely used and studied as a means to provide control education. However, they also offer a wide variety of problems to teach control. This paper concentrates on the second aspect, presenting some didactic activities that are interesting for both control and computer science/engineering students. After motivating the proposed pedagogy from a cultural point of view, also as a means to foster the necessary convergence of the two mentioned communities, some examples of activities are presented and discussed. The purpose is twofold. On one hand, the reader can see how many concepts – ranging from control structures through cyber-physical systems to process/control co-design and more – can be exemplified and experimented with, both in simulation and on real systems that virtually any student already possesses. On the other hand, and maybe most important, the usefulness of those concepts for the design – not just the control – of computing systems, can be appreciated, and constitutes a very promising research and engineering field. To this end, a brief sketch of future perspectives concludes the paper.

Forced draft evaporative cooling towers are often used for condenser cooling in small steam power plants. Conventional control strategies keep the cooling pump operating at full speed all the time, and control the cooling water temperature by modulating the tower fan speed. In this work, an energy-efficient control strategy is proposed, that minimizes the combined consumption of the tower fans and circulation pump, while also avoiding the sustained operation of the fans within some forbidden velocity range, to avoid resonance effects. The proposed strategy can be easily implemented within standard industrial control system, and is demonstrated to operate satisfactorily by a simulation study.

Desiccant wheels can improve the efficiency of air handling units, as their inherent heat recovery capabilities reduce the external energy needs. On the other hand, however, desiccant wheels introduce state variable interactions that are not present in traditional units. Hence, to actually yield the possible advantages, air handling units with desiccant wheels require accurate control, which in turn calls for dynamic wheel models that can be parametrised from design data, so as to allow for virtual prototyping, and couple reliability with numerical efficiency, to deliver the numerous system-level simulations required with an acceptable computational effort. This paper proposes a dynamic model for desiccant wheels fulfilling the above requirements. To support the proposal, examples ere reported on the use of the proposed model for the design and control of innovative unit layouts.

Many Wireless Sensor Network (WSN) services rely on time synchronisation, and since WSN nodes frequently operate in varying ambient conditions, adequate compensation for thermally-induced clock drift is needed. Also, WSN software – including both applications and operating systems – has to run on heterogeneous hardware, which requires synchronisation solutions that can be deployed with no or minimal tuning in the field. In a previous paper we proposed a joint clock synchronisation and skew/drift compensation scheme entirely realised as a decentralised discrete-time LTI control system, achieving high precision and low-power operation, and compensating thermal drift without temperature measurements. Here, conversely, we concentrate on generality with respect to hardware, and tuning-free deployment. We show that such requirements practically rule out feedforward thermal compensation (which further backs up our previous proposal), devise a methodology to tackle the problem, and present an application demonstrated by experimental tests.

In some recent papers it was shown that preemptive process schedulers in multitasking operating systems can be viewed, and above all designed, as discrete-time feedback controls with very simple (I- or PI-type) regulators, yielding significant advantages over classical scheduling policies as for time complexity and parameter interpretability. In this work, the same problem is tackled with a predictive control approach. Doing so allows to release some simplification hypotheses of the mentioned papers and to improve the achieved solutions’ flexibility, widening the application possibilities at an affordable additional cost.

Simulation is important to evaluate the energy-related performance, of a building, and for reliable results, reproducing the behaviour of the contained air volumes is particularly relevant. This is especially true if the control system is considered as part of the simulation study, for example to determine the best sensor positioning. For such a purpose, fully mixed models (i.e., for instance, a single temperature per room) easily prove inadequate, while Computational Fluid Dynamics (CFD) ones are too complex, and difficult to formulate in a modular manner, to the detriment of their usefulness if the simulator has to be used throughout the project, and not only to assess its final result. This manuscript presents an intermediate solution based on the object-oriented modelling paradigm, and implemented in the Modelica language, also reporting some examples to prove its validity.

Regulators are conceived as dynamic systems, but almost invariantly implemented as computer code. In the opinion of the authors the relationships between those two worlds are frequently overlooked in control education, although an insufficient knowledge of the involved concepts can hinder the correct operation of the realised systems. This manuscript presents a didactic activity that aims at closing the mentioned gap. The scope is for now limited modulating control, although extensions can be envisaged.

This paper presents a methodology for constructing synthesis rules suitable for PID autotuners and applicable to structurally complex process models, so as to better exploit the possibilities nowadays offered by identification techniques. The general idea is exposed and an application example, referring to a structure quite common in process control, is discussed.

In computer engineering curricula, control is typically taught only to students willing to specialise in embedded systems, real-time, and the like. Nowadays, this is becoming a problem. Control-based techniques are gaining importance as a means to manage, optimise and also design computing systems. In such a scenario, a lack of control culture is critical. However, a computer engineering curriculum may not have the time and space to introduce a suitably tailored but “complete” course on the principles of systems and control. This paper proposes a solution, based on a PID-centred activity, where the occasion is taken to introduce and stress selected general ideas.