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This paper proposes a model-based fault diagnosis and prognosis approach applied to brushless DC motors (BLDC). The objective is an early detection of mechanical and electrical faults in BLDC motors operating under a variety of operating conditions. The proposed model-based method is based on the evaluation of a set of residuals that are computed taking into account analytical redundancy relations. Fault diagnosis consist of two steps: First, checking if at least one of the residuals is inconsistent with the normal operation of the system. And, second, evaluating the set of the residuals that are inconsistent to determine which fault is present in the system. Fault prognosis consists of the same two steps but instead of considering current inconsistencies evaluates drift deviations from nominal operation to predict futures residual inconsistencies and therefore predict future fault detections and diagnosis. A description of various kinds of mechanical and electrical faults that can occur in a BLDC motor is presented. The performance of the proposed method is illustrated through simulation experiments.

An active fault tolerant control (FTC) strategy for open-loop unstable linear parameter varying (LPV) systems subject to actuator saturations and faults is proposed in this paper. At first, the nominal controller is designed using a direct approach that takes into account the actuator limits. Later, virtual actuators are added to the control scheme, such that the faulty plant is reconfigured, and the fault is hidden from the controller point of view. Conditions for designing the virtual actuator gains are designed, aiming at guaranteeing that if at the fault isolation time the closed-loop system state is inside a region defined by a value of the Lyapunov function, the state trajectory will converge to zero despite the appearance of faults within a predefined set. The theoretical results are demonstrated using a numerical example. An active fault tolerant control (FTC) strategy for open-loop unstable linear parameter varying (LPV) systems subject to actuator saturations and faults is proposed in this paper. At first, the nominal controller is designed using a direct approach that takes into account the actuator limits. Later, virtual actuators are added to the control scheme, such that the faulty plant is reconfigured, and the fault is hidden from the controller point of view. Conditions for designing the virtual actuator gains are designed, aiming at guaranteeing that if at the fault isolation time the closed-loop system state is inside a region defined by a value of the Lyapunov function, the state trajectory will converge to zero despite the appearance of faults within a predefined set. The theoretical results are demonstrated using a numerical example. An active fault tolerant control (FTC) strategy for open-loop unstable linear parameter varying (LPV) systems subject to actuator saturations and faults is proposed in this paper. At first, the nominal controller is designed using a direct approach that takes into account the actuator limits. Later, virtual actuators are added to the control scheme, such that the faulty plant is reconfigured, and the fault is hidden from the controller point of view. Conditions for designing the virtual actuator gains are designed, aiming at guaranteeing that if at the fault isolation time the closed-loop system state is inside a region defined by a value of the Lyapunov function, the state trajectory will converge to zero despite the appearance of faults within a predefined set. The theoretical results are demonstrated using a numerical example.

This work presents an optimization strategy that maximizes the leak locatability performance of water distribution networks (WDN). The goal is to characterize and determine a sensor configuration that guarantees a maximum degree of locatability while the sensor configuration cost satisfies a budgetary constraint. The method is based on pressure sensitivity matrix analysis and an exhaustive search strategy. In order to reduce the size and the complexity of the problem the present work proposes to combine this methodology with clustering techniques. The strategy developed in this work is successfully applied to determine the optimal set of pressure sensors that should be installed in a district metered area (DMA) in the Barcelona WDN.

This paper explains the methodology developed to design the yaw control system (heading control system) of the α-SAC UAV. The problem of modeling and controlling the tail motion of this UAV along a desired trajectory is considered. First, the response data of the system are collected during special flight test and a linear time invariant model is extracted by identification techniques. Then, the control system is designed and implemented using a PID feedback/feedforward control method. The technique is tested in simulation and validated in the autonomous flight of the small scale helicopter.

In this paper, a Fault Tolerant Control (FTC) strategy using a virtual sensor for Linear Parameter Varying (LPV) systems is proposed. The main idea of this FTC method is to reconfigure the control loop such that the nominal controller could still be used without need of retuning it. The plant with the faulty sensor is modified adding the virtual sensor block that masks the sensor fault. The suggested strategy is an active FTC strategy that reconfigures the virtual sensor on-line taking into account faults and operating point changes. In order to implement the virtual sensor approach, a fault estimation is required. Here, this fault estimation is provided by formulating it as a parameter estimation problem. Then, a block/batch least square approach is used to estimate additive and multiplicative faults. The LPV virtual sensor is designed using polytopic LPV techniques and Linear Matrix Inequalities (LMIs). To assess the performance of the proposed approach a two degree of freedom helicopter simulator is used.

This material is presented to ensure timely dissemination of scholarly and technical work. Copyright and all rights therein are retained by authors or by other copyright holders. All persons copying this information are expected to adhere to the terms and constraints invoked by each author's copyright. In most cases, these works may not be reposted without the explicit permission of the copyright holder The main objective of this paper is to present the MATLAB block-set that can be used for faulttolerant control of linear-parameter varying systems. In particular, the introductory part of the paper presents a theoretical background regarding the fault identification and control strategy. Subsequently, it is shown how to implement these theoretical results in Matlab/Simulink. The final part of the paper presents the experimental study regarding the twin-rotor system, which confirms the effectiveness of the developed tool.

In this paper the problem of robust fault detection using an interval observer for dynamic systems characterized by LPV (Linear Parameter Varying) models is presented. The observer face the robustness problem using two complementary strategies. Parametric modeling uncertainties are considered unknown but bounded by intervals. Their effect is addressed using an interval state observation method based on zonotope representation of the set of possible states. The observer gain is designed via pole placement using LMI (Linear Matrix Inequalities) formulation. The method is applied to a LPV representation of a Twin Rotor MIMO System.

La investigació sobre l’avenç i la innovació tecnològica és un dels principals objectes d’estudi en la indústria aeroespacial. El reús de vehicles espacials és un d’ells i es tracta d’un important aspecte per disminuir els grans costos i recursos que una missió espacial implica, minimitzant també l’impacte ambiental. Aquest treball desenvolupa l’estudi i la implementació del control per la recuperació segura dels sistemes de llançament d’un coet. Per tal d’assolir aquest anàlisis, s’avaluen els actuals coets reutilitzables, seleccionant el Falcon 9 del SpaceX com a model principal en el qual el projecte es centra. Un cop caracteritzat aquest sistema en particular, es determina la modelització d’equacions del problema amb l’objectiu de crear un programa en l’entorn de Matlab i efectuar simulacions. La necessitat d’un sistema de control és inferida mitjançant els resultats de les primeres simulacions a causa de l’absència dels paràmetres d’aterratge segur, d’entre els quals el més important és una velocitat final pròxima a 0. Conseqüentment, es proposen i comparen diferents controladors lineals a fi d’aconseguir el comportament desitjat del sistema. No obstant, les no-linealitats del problema sumades a les limitacions d’aquests controladors incrementa la complexitat, a causa de la considerable quantitat d’entrades de control. Per aquests motius, el sistema es simplifica englobant les forces i els moments en les corresponents resultants amb les quals la totalitat de les superfícies de control han de contribuir. Seguint aquesta metodologia, el sistema desenvolupat consisteix en controlar la velocitat mitjançant les forces i l’angle de capcineig amb els moments. D’aquest últim, s’extreu com a conclusió que el Control Predictiu basat en Model disposa d’una tendència a ajustar-se millor a la consigna que el PID. En definitiva, les limitacions d’aquests controladors tenen un impacte en la resposta final i, per aquesta raó, es requereixen de propostes més complexes per tal d’adquirir una aproximació encara més propera al problema real, com per exemple controladors no lineals o un segon nivell d’aquests per determinar les accions que cada dispositiu de control haurien d’efectuar a partir de les resultants de les forces i els moments, les quals són les entrades del sistema que ja ha estat controlat. The research of advanced and innovative technologies is one of the main concerns within the aerospace industry. Spacecraft reusability is one of them, being an important aspect to diminish the huge costs and resources that a space mission implicate, minimising also the environmental impact. This thesis develops the study and the implementation of the control for the safe recovery of the launch system of a rocket. In order to accomplish this analysis, the current successful reusable rockets are evaluated and the Falcon 9 from the SpaceX is selected as the main model in which the project is focused on. Once characterised this particular system, the problem equation modelling is determined to create a framework within a Matlab environment and perform simulations. The need of a control system is inferred through the first simulations results due to the lack of the safe landing parameters, being the most important a final velocity close to 0. Consequently, different linear controllers are proposed and compared to achieve the desired behaviour from the system. Nevertheless, the non-linearity of the problem added to these controllers limitations increase the complexity, due to the considerable quantity of control inputs. For these reasons, the system is simplified by computing the resultant forces and moments that the overall control surfaces must contribute. Following this methodology, the developed system consists in controlling the velocity with the forces and the pitch angle with the moments. From this last, the extracted conclusion is the Model Predictive Control tendency to dispose of a better adjustment to the setpoint rather than the PID. In definitive, the limitations of these controllers have an impact to the final response and, for this reason, more complex proposals would be required to acquire an even closer approach to the real problem, such as nonlinear controllers or a second level of these type of controllers to determine the performance of each control device from the resultants of the forces and the moments, which are the inputs of the already controlled system.

The project is based on the design of the control system of a chemical process through the engineering diagram. First, the process under consideration has been chosen. It consists in the mixture of two fluids, initially stored at different heights, which are mixed in a reactor. The reaction of this mixture where different condensation gases appear, are later reused to continue the mixture and obtain the final product. Next, the instrumentation required for the control system has been determined and then implemented in the process. In order to have a clearer view about that implementation, an engineering diagram has been sketched. Once the necessary process and instrumentation have been defined, the control system has been designed using a controller with different modules connected to it, which will allow to interconnect the elements of the process and the control software. Then, the programming has been realised using the software corresponding to the controller so as all the instrumentation works together and the process achieves the requirements imposed at the beginning of the project

Este proyecto trata del estudio y diseño de un sistema de control para un robot móvil, anticipando obstáculos tipo rampa, utilizando los sensores disponibles. El objetivo de control consiste en hacer que el sistema sea capaz de superar estos obstáculos de forma óptima, cosa que no sería posible en condiciones de control simples, evitando posibles saturaciones innecesarias en la señal de la acción de control