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Scientific article published (with gold open access option) on the journal Meccanica (Springer). The present file contains the published version (with no further modifications) of the paper. Abstract: Dielectric elastomer generators (DEGs) are soft electrostatic generators based on low-cost electroactive polymer materials. These devices have attracted the attention of the marine energy community as a promising solution to implement economically viable wave energy converters (WECs). This paper introduces a hardware-in-the-loop (HIL) simulation framework for a class of WECs that combines the concept of the oscillating water columns (OWCs) with the DEGs. The proposed HIL system replicates in a laboratory environment the realistic operating conditions of an OWC/DEG plant, while drastically reducing the experimental burden compared to wave tank or sea tests. The HIL simulator is driven by a closed-loop real-time hydrodynamic model that is based on a novel coupling criterion which allows rendering a realistic dynamic response for a diversity of scenarios, including large scale DEG plants, whose dimensions and topologies are largely different from those available in the HIL setup. A case study is also introduced, which simulates the application of DEGs on an OWC plant installed in a mild real sea laboratory test-site. Comparisons with available real sea-test data demonstrated the ability of the HIL setup to effectively replicate a realistic operating scenario. The insights gathered on the promising performance of the analysed OWC/DEG systems pave the way to pursue further sea trials in the future. ; This project has received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 893674 (DEtune)

This paper presents an hardware-in-the-loop (HIL) simulation system tool to test and validate an autonomous free running model system for ship hydrodynamic studies with a view to verification of the code, the control logic and system peripherals. The computer simulation of the plant model in real-time computer does not require the actual physical system and reduces the development cost and time for control design and testing purposes. The HIL system includes: the actual programmable embedded controller along with peripherals and a plant model virtually simulated in a real-time computer. With regard to ship controller design for ship model testing, this study describes a plant model for surge and a Nomoto first order steering dynamics, both implemented using Simulink software suit. The surge model captures a quasi-steady state relationship between surge speed and the propeller rpms, obtained from simple forward speed towing tank tests or derived analytically. The Nomoto first order steering dynamics is obtained by performing the standard turning circle test at model scale. The control logic obtained is embedded in a NI-cRIO based controller. The surge and steering dynamics models are used to design a proportional-derivative controller and an LQR controller. The controller runs a Linux based real-time operating system programmed using LabVIEW software. The HIL simulation tool allows for the emulation of standard ship hydrodynamic tests consisting of straight line, turning circle and zigzag to validate the combined system performance, prior to actual for use in the autonomous free-running tests.

The miniaturization of spacecraft has brough the possibility of conducting space missions to a vast portion of private enterprises and scientific institutions. The inaccessibility of modest developers to the resources that governmental agencies and primary contractors utilize to develop conventional satellites has not been an obstacle for them to apply different, more agile and risk-seeking approaches. However, the failure rate of Small Satellite missions has increased to a higher degree than the total number of missions, particularly if only CubeSats are considered. The research conducted in this thesis proposes an improvement to the development of space systems by focusing on the verification and validation processes. For that, the thesis revolves around two main areas. First, the thesis deals with the engineering methodology. The notions of concurrent engineering are generalized and combined with the test-driven development and behavior-driven development methodologies to perform the parallel, yet integrated, development of the various spacecraft subsystems that can be at different maturity levels. For example, these processes have been applied in-house to the development of onboard computers and telecommunication systems. The proposed methodology allows for the automation of the engineering workflow and the early detection and correction of defects in the system by frequently testing it along the process. Secondly, the research also deals with the development and utilization of a simulation environment that fits the proposed methodology. The thesis provides advancements on hardware-in-the-loop simulation techniques with a particular focus on frictionless platforms. Such a platform can perform, but is not limited to, dynamic simulations. Additionally, the thesis also provides the characterization of the platform to use it as a reference for comparison with other similar ones. All in all, the simulation environment has demonstrated to provide the versatility needed by the methodology. Such environment has served as a platform to develop different subsystems from the simulation of physical models to the testing of actual hardware prototypes. Two studies are provided as examples of such accomplishments, i.e., a study with the remote simulation of cooperative maneuvers and a different one with the development of flexible appendages for a spacecraft.

The increasing requirements to further reduce pollutant emissions, particularly with regard to the upcoming Euro 7 (EU7) legislation, cause further technical and economic challenges for the development of internal combustion engines. All the emission reduction technologies lead to an increasing complexity not only of the hardware, but also of the control functions to be deployed in engine control units (ECUs). Virtualization has become a necessity in the development process in order to be able to handle the increasing complexity. The virtual development and calibration of ECUs using hardware-in-the-loop (HiL) systems with accurate engine models is an effective method to achieve cost and quality targets. In particular, the selection of the best-practice engine model to fulfil accuracy and time targets is essential to success. In this context, this paper presents a physically- and chemically-based stochastic reactor model (SRM) with tabulated chemistry for the prediction of engine raw emissions for real-time (RT) applications. First, an efficient approach for a time-optimal parametrization of the models in steady-state conditions is developed. The co-simulation of both engine model domains is then established via a functional mock-up interface (FMI) and deployed to a simulation platform. Finally, the proposed RT platform demonstrates its prediction and extrapolation capabilities in transient driving scenarios. A comparative evaluation with engine test dynamometer and vehicle measurement data from worldwide harmonized light vehicles test cycle (WLTC) and real driving emissions (RDE) tests depicts the accuracy of the platform in terms of fuel consumption (within 4% deviation in the WLTC cycle) as well as NOx and soot emissions (both within 20%).

Bei einer Hardware-in-the-Loop (HiL)-Simulation wird die reale Steuerungstechnik mit einer experimentierfähigen Maschinensimulation verbunden. Soll das Bewegungsverhalten des Materialflusses in der Maschinensimulation zur Generierung von Steuerungssignalen berechnet werden, so müssen die harten Echtzeitanforderungen einer HiL-Simulation eingehalten werden. Dieser Beitrag betrachtet verschiedene Materialflussmodelle und gibt das Ziel eines mehrskaligen Simulationsmodells für die HiL-Simulation vor.
 
A Hardware-in-the-Loop (HiL) simulation couples real control technology with an experimental machine simulation. When computing the movement behavior of a material flow in the machine simulation to generate control signals, the hard real-time requirements of a HiL-simulation must be considered. This article checks different material flow models and defines the objective of a multi-scale material flow model for HiL-Simulation.

Unmanned Aerial Vehicle (UAV) swarm applications, algorithms, and control strategies have experienced steady growth and development over the past 15 years. Yet, to this day, most swarm development efforts have gone untested and thus unimplemented. Cost of aircraft systems, government imposed airspace restrictions, and the lack of adequate modeling and simulation tools are some of the major inhibitors to successful swarm implementation. This thesis examines how the OpenEaagles simulation framework can be extended to bridge this gap. This research aims to utilize Hardware-in-the-Loop (HIL) simulation to provide developers a functional capability to develop and test the behaviors of scalable and modular swarms of autonomous UAVs in simulation with high confidence that these behaviors will prop- agate to real/live ight tests. Demonstrations show the framework enhances and simplifies swarm development through encapsulation, possesses high modularity, pro- vides realistic aircraft modeling, and is capable of simultaneously accommodating four hardware-piloted swarming UAVs during HIL simulation or 64 swarming UAVs during pure simulation.

La situación energética actual está dominada por los combustibles fósiles, especialmente por el petróleo. Esta dependencia se está conviertiendo en arriesgada debido a las decrecientes reservas, a la incertidumbre de los recursos de petróleo y a las consecuencias económicas y políticas de una concentración de reservas en países de Oriente Medio. El sector transportes tiene una particular dependencia del petróleo como combustible y es una fuente de contaminación debido a su combustión. De cara a reducir esta dependencia se están introduciendo energías renovables como fuentes alternativas de energía. Las más comunes son la eólica y la fotovoltaica, aunque existen otros tipos, como las energías mareomotriz, de gradiente térmico, biomasa o undomotriz. El principal inconveniente de estas energías es su carácter no programable, que fomenta el uso de sistemas de almacenamiento de energía. Las energías renovables mencionadas no son aplicables a vehículos, por lo que para el sector transportes es más interesantes el uso de vectores energéticos tales como el hidrógeno. El hidrógeno puede ser un sustituto del petróleo para aplicaciones vehiculares, pero primero se han de resolver ciertos problemas, como son el elevado coste, la seguridad y el establecimiento de una infraestructura de distribución de hidrógeno. Como en el caso de los sistemas estacionarios renovables, las pilas de combustible de aplicación vehicular necesitan sistemas de almacenamiento de energía que sean capaces de suministrar picos de potencia durante la aceleración o subiendo una pendiente. Esta situación energética ha provocado un incremento del desarrollo e investigación de sistemas electroquímicos, tales como las pilas de combustible, las baterías y los supercondensadores. Sobre todo, se está realizando un esfuerzo en el diseño, modelado, control y fabricación de estos sistemas, que permita su implantación tanto en aplicaciones estacionarias como vehiculares o portátiles. Esta Tesis presenta el modelado dinámico no lineal de sistemas electroquímicos tales como las pilas de combustible, las baterías y los supercondesadores a través de ensayos en el dominio de la frecuencia, además de su validación con resultados experimentales. Se propone un sistemas por unidad para aquellos sistemas electroquímicos activos (pila de combustible y batería). Estos sistemas son una herramienta útil para el diseño y comparación, debido a la gran variedad de tensiones y capacidades que pueden encontrarse, por ejemplo, en las baterías. Además, se ha propuesto un método de ensayo de espectroscopía de la impedancia para supercondensadores durante elevadas corrientes. Los resultados obtenidos y la comparación con resultados experimentales son muy positivos. Por último, se ha realizado una simulación hardware-in-the-loop de sistemas híbridos de energía. La simulación realizada presenta un coste y complejidad menor que otros tipos de simulaciones. Esto es debido a que los elementos más caros, como es la pila de combustible, son sustituidos por una fuente de potencia programable capaz de reproducir la dinámica de tensión y corriente de la pila de combustible. Además, se propone un simulador de vehículo, capaz de reproducir, tanto la potencia demandada por el vehículo como el frenado regenerativo. La pila de combustible simulada y una batería real alimentan en paralelo al vehículo simulado, permitiendo llevar a cabo una simulación por unidad del conjunto y la prueba de diferentes estrategias de control para un determinado ciclo de conducción. ___________________________________________________ ; The current energy situation is dominated by fossil fuel, especially oil. This dependency is turning critical due to the reducing reserves, uncertain oil resources, and political and economical ramifications of a concentration of fossil fuel reserves on the Middle East countries. The transportation sector is especially dependant on oil, and the combustion of oil produces environmentally harmful emissions. Renewable energies are being introduced to reduce this fossil fuel dependency and emissions. The most extended are wind and solar photovoltaic, but other types such as tidal, thermal gradient, biomass or wave energy are also under research. The principal disadvantage of these renewable energies is its non-dispatchable nature, which forces the use of energy storage systems. The renewable energies mentioned are not viable for the transportation sector, which considers more interesting other energetic vectors such as hydrogen. Hydrogen could substitute oil, but must first overcome cost, safety and hydrogen filling stations infrastructure problems. Just as in the case of stationary systems, fuel cells need energy storage systems, in this case to supply high power peaks during acceleration. This energetic situation has caused an increase of the research and development of electrochemical systems, such as fuel cells, batteries and ultracapacitors. Intense research is being carried out in modeling, control and manufacture in order to apply them to both vehicular and stationary applications. This Thesis presents the nonlinear dynamic modeling of electrochemical systems, such as fuel cell, batteries and ultracapacitors, through frequency domain tests and its validation with experimental tests. A per-unit system has been proposed for the active electrochemical systems: fuel cell and battery. This per-unit approach has revealed as a useful tool for comparison and design, due to the great disparity of voltages and capacities, e.g. in batteries, which can be found. Moreover, an experimental setup has been proposed in order to allow the electrochemical impedance spectroscopy tests of ultracapacitors during high current loads. Tests were carried out satisfactorily and a precise model was obtained. Finally, a hardware-in-the-loop simulation for hybrid energy sources is presented. The simulation carried out has a lower cost and complexity compared to the real system. This is due to the fact that the higher cost system, the fuel cell and hydrogen installation, was substituted by a controlled dc power source able to reproduce its current and voltage evolution. Moreover, a vehicle simulator, able to reproduce the vehicle power demand and regenerative breaking is proposed. The simulated fuel cell and a real battery are connected to the simulated vehicle, allowing to carry out a per-unit simulation of di®erent control strategies for a particular driving cycle.