CONTROL DEVICES

Author: AZORIN POVEDA JOSE M..
Year: 2003.
University: MIGUEL HERNÁNDEZ DE ELCHE.
Place of defense: ESCUELA POLITÉCNICA SUPERIOR.
Place of preparation: ESCUELA POLITÉCNICA SUPERIOR DE ELCHE.

Summary: This Doctoral Thesis aims to present a new method of design and control systems teleoperados with delays in the transmission based on the convergence of states. The method allows the slave master to continue, despite the existence of delays, besides being able to establish the dynamics of the slave, as well as the dynamics of the error between the master and slave. First described in detail the method of design and Remote control for a system with delays in transmission in which the master and slave are represented by second-order differential equations, explaining modeling system state variables in Remote it is based on the method. Next, we studied in a comprehensive manner the dynamic behavior of the system Remote, indicating how it is affected by the design parameters considered. It also examines the robustness of the method of control to slight variations in the design parameters. Here are the criteria that are used to analyze the stability of asymptotic Remote system with delays. By these criteria are studying the influence of the design parameters on the stability asymptotic, indicating under what conditions the system becomes unstable, or if it is unstable, as you can stabilize. In addition, the method of generalized design and control systems teleoperados with delays in the transmission to the case in which the master and slave system Remote be modeled by linear differential equations of order n. Finally, the experimental results are shown obtained by applying the method of design and control a system Remote real one degree of freedom.

Author: GARETA ALBO RAQUEL.
Year: 2004.
University: ZARAGOZA.
Place of defense: Centro Politécnico Superior.
Place of preparation: CENTRO POLITÉCNICO SUPERIOR.

Summary: The use of biomass as a fuel alternative to traditional energy sources is faced with various problems that are preventing its spread. One of the most important is the poor functioning of boilers due to the formation of deposits on the surfaces of trade. Moreover control systems have evolved dramatically in the last decade, so that they have control very powerful tools that can be used to complex problems. In this thesis has developed a monitoring system based on intelligent models for ltratar minimize the effects of deposits on heat transfer. The monitoring system consists of four modules in a manner that is capable of: 1. Assessing the current state of fouling of different surfaces exchange boiler. 2. Predicting what will be the evolution of these deposits in the event that is activated or not the cleaning cycle. 3. Modelizar the response of the boiler before the evolution of such deposits. 4. Deciding whether or not to activate the blowers. The first three modules are built using neural networks and the latter by an expert system basad in Fuzzy logic. The main contribution of the thesis are the establishment of a rigorous methodology of working with neural networks that pemite obtain excellent results, the implementation of the monitoring system to a boiler real and predicting the evolution of fouling through a series of temporary values of a variable which it has proven to be sensitive only to the effect of deposits on heat transfer.

Author: VELASCO GARCIA MANUEL.
Year: 2005.
University: POLITÉCNICA DE CATALUÑA.
Place of defense: Aula 28.8 de l'ETSEIB.
Place of preparation: EDIFICI U DESPATX 518 Campus SUD.

Summary: In this PhD thesis solutions are given for some of the problems that appear when real-time systems must attend simultaneously to multiple control tasks. Emphasis is given to those problems which affect the quality of control. A multitasking real-time system distributes one or more resources among several control loops. The shared resource can be either a processor or a network. Variations in the execution periods and in the latencies inherent to the control algorithms appear regardless of the sharing method used. When the shared resource is a processor, the problem lies in the impossibility of running two algorithms at the same time. This means a time-ordered running, and hence variations in the basic parameters of the controller. When a network is shared, no two messages can be transmitted at the same time so, once more, a time-ordering of the messages is imposed and, again, variations in the controller parameters arise. The first part of the thesis is an analysis of the effects of those variations upon the control. There are two objectives: First. To analyze the effect of using multitasking real-time systems upon the controllability and observability of the controlled systems. Second. To obtain stability analysis techniques for the real-time control systems. The results of the above are: First. Controllability and observability are maintained when the controller is implemented in a real-time platform. Second. Stability analysis for real-time control systems can be done by probabilistic techniques and by intervalar techniques. The second part of the thesis studies the efficiency of real-time implemented control loops. This is done by analyzing the best way to distribute the available resources among the control loops taking account of the state of the control. The guiding idea is "to give more resources to the control loop in more need of them". The two objectives are: Third. Management of overload conditions in control tasks. Fourth. Optimal distribution among the control loops of the part of resources not already used. To those ends algorithms are given to distribute resources so as to obtain the best efficiency. The results are: Third. An algorithm that minimizes the number of controllers for a control loop but allows it to react to overloads. Fourth. An algorithm to optimally distribute resources among control loops. Finally a case study is presented about the communications system of a distributed control system. The optimal distribution techniques (fourth result) are used to show how they can be implemented on a CAN network (Controller Area Network).

Author: GARCÍA MORALES ISABEL.
Year: 2005.
University: MÁLAGA.
Place of defense: ESCUELA TÉCNICA SUPERIOR DE INGENIEROS INDUSTRIALES.
Place of preparation: ESCUELA TÉCNICA SUPERIOR DE INGENIEROS INDUSTRIALES.

Summary: This thesis deals with the problem of Cartesian control of movements for a robot carrying the camera in laparoscopic surgery. Specifically, it proposes an algorithm to generate trajectories spherical online compensates for errors orientation of the camera produced by the uncertainty in the position of flcro (where the lens is inserted into the abdomen of the patient). It has also taken into account the fact that the trajectories calculated not saturen actuators Manipulator through a study based on the concept of manipulabilidad. The control strategy has been developed implanted in the robotic assistant for surgery laparoscopica MRA (designed and built during the conduct of this work), and he has done a clinical trial on two sets of sixteen patients.