Essa dissertação tem por objetivo o desenvolvimento de uma plataforma para testes de controladores de voo. Tal plataforma consiste em um hardware executando algoritmos de controle e atuando numa aeronave simulada em software de simulação de voo. O software de simulação escolhido, baseado na experiência prática de pilotos profissionais, foi o Microsoft Flight Simulator (MSFS), para o qual desenvolveu-se o modelo gráfico e dinâmico do quadricóptero AscTec Pelican. A comunicação entre o MSFS e o hardware é feita pela interface USB através do software FVMS v2.0 desenvolvido em ambiente DELPHI® 7.0 exclusivamente para este trabalho. O FVMS é capaz de ler o estado das variáveis de voo no MSFS, enviá-las para o hardware externo executar o controle, receber os sinais de controle de volta e utilizá-los no MSFS. O projeto e execução do hardware externo com controlador dsPIC também foi realizado neste mesmo trabalho. A título de avaliação de desempenho, também foi implementado um controlador robusto do tipo H∞ linear, desenvolvido pela equipe ART (Aerial Robots Team) da Escola de Engenharia de São Carlos. O mesmo controlador também foi aplicado na arquitetura software in the loop, na qual o controle é executado dentro do próprio FVMS, para comparação de desempenho entre os dois sistemas. Ao término do trabalho, as características de desempenho do sistema como um todo ficam bem evidenciadas através dos testes de estabilidade com e sem distúrbios executados em ambas arquiteturas de controle. / This dissertation aims to develop a platform for flight controllers tests. It platform consists of an electronic hardware where the control\'s algorithms will be executed and a virtual aircraft is simulated in flight simulation software. The chosen simulation software, based on practical experience of professional pilots, was Microsoft Flight Simulator (MSFS). The graphic and dynamic model of quadrotor AscTec Pelican was developed to perform inside the software. The communication between the MSFS and the hardware is made by USB interface through FVMS v2.0 software developed in DELPHI® 7.0 environment, exclusively for this work. The FVMS can read the status of the flight variables in MSFS, send them to the external hardware, receive control signals back and write them in MSFS. The design and implementation of external hardware with dsPIC controller was also developed ons ame work. For performance evaluation of the system, it was also implemented a robust linear H∞ controller, developed by ART team (Aerial Robots Team) of the School of Engineering of São Carlos. The same controller was also applied using software in the loop architecture, in which the control is performed inside FVMS, to compare performance between the two architectures. In the end of the work, the performance characteristics of the systems were well evidenced by the stability tests carried out with and without disturbances in both control architectures.

No description available.

In this thesis, we present the Weil representation over loop symplectic groups. Then we study the question of whether or not the Schrodinger representation and the Weil representation are continuous. Finally, we define a cocycle of the rank 2 symplectic group, adapt Kubota's theorem to this case and verify that it splits over a subgroup.

No description available.

Abstract Not Provided. / Thesis / Master of Science (MSc)

La comunicación celular es un proceso fundamental para la supervivencia de los organismos. Gracias a las distintas vías de comunicación, las células reciben e interpretan mensajes del exterior, los cuales inducen respuestas necesarias para el correcto funcionamiento de dichas células y del organismo que estas constituyen. Los canales iónicos activados por ligandos (LGIC) son proteínas integrales de membrana encargadas de transducir la señal proveniente del exterior hacia el interior celular. Sus vías de transducción son muy variadas, pero en general llevan a dos respuestas fundamentales según el receptor implicado, respuesta de excitación o respuesta de inhibición. Dentro del grupo LGIC existen tres familias de receptores, cada una conformada por varios miembros relacionados evolutivamente. Dichas familias se clasifican como: canales catiónicos activados por glutamato, canales activados por ATP y los receptores pertenecientes a la familia Cys-loop. En el presente trabajo de tesis doctoral estudiamos los mecanismos de activación de dos miembros de la familia de receptores Cys-loop, el receptor de acetilcolina de músculo adulto (AChR) y el receptor de serotonina homopentamérico tipo 3A (5-HT3AR). El AChR es considerado el modelo, tanto estructural como funcional, para todos los miembros de esta familia. Para un mejor entendimiento de los mecanismos que llevan al correcto funcionamiento de dichos receptores, es necesario: a) conocer su estructura molecular y los mecanismos que gobiernan su activación, y b) definir un modelo cinético que logre representar los estados en los cuales se encuentra el receptor y los pasos afectados por mutaciones o moduladores. En base a estudios de mutagénesis dirigida, determinamos el aporte de los residuos 15 de M1 de las subunidades ,  y  para el correcto funcionamiento del AChR. Además, definimos la relación entre el volumen del residuo en dicha posición y el efecto provocado sobre la eficiencia de gatillado del canal. Observamos que para la subunidad  el aumento del volumen del residuo en 15 lleva a una disminución en la constante de gatillado del canal. En cambio, para las otras subunidades, ocurre el efecto opuesto. Demostramos que los residuos 15 de M1 y 11 de M2 de la subunidad  interaccionan directamente. Dicha interacción explicaría la realción observada entre el volumen del residuo en 15 de M1 y la eficiencia del canal, donde la interacción 11-15 se vuelve más significativa al aumentar el volumen del residuo en 15, llevando a una reducción en la eficiencia del gatillado del canal. Debido a la baja conductancia del canal del 5-HT3AR, solo han sido propuestos hasta el momento modelos cinéticos basados en el análisis de corrientes macroscópicas. Utilizando el receptor de serotonina de alta conductancia (5-HT3AR-AC) obtuvimos corrientes macroscópicas y registros de canal único. En base a dichos registros, definimos un modelo cinético que describe con alto grado de exactitud los datos experimentales. Este es el primer modelo que, además de representar lo observado a nivel de corrientes macroscópicas, describe también la activación del receptor a nivel de canal único. Por otro lado, realizamos mutaciones sobre el 5-HT3AR-AC en los residuos 10 y 14 del segmento M4. Dichos residuos fueron demostrados como importantes en el gatillado del AChR y presentan un patrón de conservación particular entre las subunidades de estos dos receptores. Confirmamos que ambos residuos son importantes para el correcto funcionamiento del 5-HT3AR, donde las mutaciones en 10 afectaron la activación del receptor a nivel de canal único y las mutaciones en 14 solo mostraron efectos a nivel de las corrientes macroscópicas. Utilizando los datos obtenidos a partir del receptor mutado en 10 de M4, realizamos el análisis cinético en base al esquema propuesto. Determinamos que las velocidades afectadas fueron fundamentalmente de apertura y cierre del canal, similar a lo demostrado para el residuo equivalente del AChR. Nuestros resultados brindan importante información sobre la intervención de los segmentos transmembranales en el correcto funcionamiento de receptores de la familia Cys-loop. Asimismo, muestran cómo la función de determinados aminoácidos se ha conservado durante la evolución. Además, definimos el primer modelo cinético para el 5-HT3AR, el cual representa correctamente la activación de este receptor, tanto a nivel de corrientes macroscópicas como de canal único. La utilización de este modelo será de gran apoyo al entendimiento de los efectos generados por mutaciones o la acción de moduladores de la funcionalidad de dicho receptor. / Cellular communication is a fundamental process for survival of the organisms. Thanks to different signaling pathways, cells can receive messages from the environment which induce responses that allow appropriate functioning of these cells and the organism that they constitute. Ligand-gated ion channels (LGIC) are integral membrane proteins involve in transduction of signals from the external side of the cell. These signaling pathways are diverse, but in general, they can generate one of both responses: excitatory or inhibitory response. The LGIC group is composed by three different families of receptors: the glutamate-activated cationic channels, the ATP-gated channels, and the Cys-loop receptors. In the present thesis we studied the mechanism of activation of two members of the Cys-loop receptor family, the nicotinic acetylcholine receptor (AChR) and the homopentameric serotonin type 3A receptor (5-HT3AR). The AChR has been the structural and functional model of all members of this family. For a better understanding of the mechanisms that lead to the correct functioning of these receptors is necessary to: a) know its molecular structure and the mechanisms which govern its activation, and b) define a kinetic model that describes its activation and elucidate how mutations or modulators can affect the transitions between different conformational states. By combining site-directed mutagenesis with electrophysiological studies we determine the contribution of residues at position 15 of M1 in ,  and  subunits to the correct functioning of the AChR. We also define the relationship between the volume of the residue at this position and efficacy for channel gating. We show that the increase in the volume of residue at 15 of M1 of the  subunit impairs channel gating, whereas the opposite effect is observed for the same position in  and  subunits. Furthermore, we demonstrate that there is a direct interaction between residues at 15 of M1 and 11 of M2 of the  subunit. This explains the relationship between the volume of the residue at 15 of M1 and the efficiency of channel: the increase in the volume of the residue at 15 of M1 may restrict the movement of M2 through its interaction with the residue at 11 of M2, thus leading to a reduction in channel gating efficiency. Due to the low conductance of the 5-HT3AR, different kinetics models proposed until now have been based on macroscopic currents. Using the high conductance form of this receptor (5-HT3AR-HC) we recorded macroscopic currents and single-channel events. On the basis of these recordings we defined a kinetic model that closely describes the experimental data. In addition, we introduced mutations at positions 10 and 14 of the M4 transmembrane segment of the 5-HT3AR-HC. Residues at these positions have been shown to be important for the correct functioning of the AChR, and they show a particular conservation pattern among 5-HT3R and AChR subunits. We demonstrate that these residues are important for the appropriate functioning of the 5-HT3AR. Mutations at 10 of M4 affect the single-channel properties, and mutations at 14 of M4 affect the decay rate of macroscopic currents and the potency for activation. With the single-channel data obtained for 5-HT3AR-HC mutated at 10 of M4, we performed kinetic analysis on the basis of the scheme proposed in this thesis. The analysis reveals that mutations at 10 affect mainly opening and closing rates from the slowest open state. This result is similar to that previously reported for AChR, indicating that the function of this position is conserved among members of the same family. Our results provide important information about the involvement of transmembrane segments in the correct functioning of receptors from the Cys-loop superfamily. These results reveal how the function of some amino acids has been conserved along evolution. In conclusion, we defined the first kinetic model for the 5-HT3AR, which perfectly represents the activation of this receptor at both macroscopic and single-channel level. Moreover, our kinetic model provides a foundation for studying the contribution of residues to receptor function and for understanding molecular mechanisms of drug modulation.

Phase Locked Loop (PLL) is an integral component of clock generation circuits. A third order Charge Pump PLL (CPPLL) is most widely employed PLL architecture due to its zero steady state phase error. A monolithic implementation of such a CPPLL presents numerous challenges to PLL designers, the number of such challenges vary depending on the process technology employed and the end application. One such challenge that is worth mentioning is the on-chip integration of the second order passive loop filter. The area occupied by the second order passive loop filter is mainly determined by the zero determining capacitance (CZ). A low loop bandwidth CPPLL has a higher CZ value, and hence consumes a larger die area than a large loop bandwidth CPPLL. Literature survey shows that the problem of higher CZ value in low loop bandwidth CPPLL is addressed by using some form of emulation techniques. A relatively simpler emulation technique is the use of dual charge pump based loop filter. Existing dual charge pump based loop filter consume extra elements (such as summer that need opamps to realize the summer function) for achieving low CZ value. These extra elements consume extra area and additional power. We present two types of Summer-Less Dual Charge Pump (SDCP) based loop filter designs that do not need extra elements and still achieves low CZ value and this is achieved by using a second charge pump in an appropriate way. A test chip was implemented in 0.13µm UMC MMRFCMOS process to verify the presented circuits. The presented SDCP based loop filter circuits are particularly useful in designs employing multiple CPPLL’s and design employing low loop bandwidth CPPLL’s. Another challenge worth-mentioning is the frequency ranges over which the PLL can be locked. The Voltage Controlled Oscillator (VCO) of PLL mainly determines the frequency locking range of a PLL. A typical VCO has a frequency locking range of usually 1:2 to 1:3. The VCO frequency tuning range reduces with reduction in supply voltage. This poses a serious problem in low supply voltage applications that demand a wide frequency locking range, sometimes greater than 1:3. We have addressed this problem of wide PLL lock range, by using an Analog Frequency Detector. A wide frequency lock range is achieved, either by dynamically modifying the VCO or the feedback divider of PLL. Both the approaches are equally feasible. The frequency detector is used for dynamically modifying the VCO or the feedback divider of PLL. Two test chips were implemented to verify the presented Analog Frequency Detector scheme. A testchip implemented in 0.25µm CSM analog process achieves wide frequency lock range by dynamically modifying the feedback divider of PLL. Another testchip implemented in 0.13µm UMC MMRFCMOS process achieves wide frequency lock range by dynamically modifying the center frequency of the VCO. Presented analog frequency detection scheme is particularly useful in applications that demand wide PLL lock range from a single die.

Passenger safety and comfort are important aspects in the process of vehicle development. The world is heading towards developing the safest possible vehicle on the road. Using vehicle motion control functions is one of the ways to enhance vehicle stability. These motion control functions need to be developed in an energy optimised way. By complementing some of the development process with virtual models, both the development time and cost could be minimised. Hence, a sustainable way of control function development could be achieved. In order to verify, validate and calibrate vehicle motion control functions, an accurate model of the virtual vehicle is required. Hence, a research question on how good the virtual model needs to be for the purpose has been addressed. This report suggests a framework in order to determine the capabilities of a virtual vehicle.In this report, a comparison study has been carried out by exciting the real car and virtual model of a Volvo XC90 with a focus of covering the six degrees of freedom (Yaw, pitch, roll, longitudinal, lateral and vertical). A semi automated framework that possesses the capability of automating the testing in a virtual platform has been established. From the test results, the virtual vehicle capabilities were determined. Further, in the second part of the report, an example use case has been considered by taking two calibration sets of Electronic stability control (ESC) system in order to verify the previously established framework.The analysis includes various levels of plant and controller complexity such as Model-in-loop, Software-in-loop and Hardware-in-loop and on two different road surfaces, low friction and high friction. From the observations, the virtual models considered correlates well for the purpose of verification and validation. However, for the purpose of calibration, the models need to be fine-tuned in the virtual platform. Furthermore, the correlation on low friction road surface could be improved by simulating the tests using an advanced tyre model. Overall, this study helps in choosing the correct complexity of various subsystems in a vehicle for the purpose of verification, validation and calibration of vehicle motion control functions. / Passagerarsäkerhet och komfort är viktiga aspekter i utvecklingen av ett fordon. Världen är på väg mot att utveckla säkraste möjliga fordon på vägen. Användning av fordonetse rörelsekontrollfunktioner är ett av sätten att förbättra fordonets stabilitet. Dessa rörelsekontrollfunktioner måste utvecklas på ett energioptimerat sätt. Genom att komplettera en del av utvecklingsprocessen med virtuella modeller kan både utvecklingstid och kostnad minimeras. Därför kan ett hållbart sätt att utveckla funktionerna för kontrollfunktioner uppnås. För att verifiera, validera och kalibrera fordonets rörelsekontrollfunktioner krävs en detaljerad modell av ett virtuellt fordon. Därför har en forskningsfråga om hur bra den virtuella modellen måste vara för ändamålet behandlats. Denna rapport föreslår ett ramverk för att bestämma funktionerna hos virtuella fordon.I denna rapport har en jämförelsestudie genomförts genom att excitera den verkliga bilen och den virtuella modellen av en Volvo XC90 med fokus på att täcka de sex frihetsgraderna (gir, nick, roll, längs, lateral, vertikal). Ett semi-automatiserat ramverk som har förmågan att automatisera testningen i en virtuell plattform har skapats. Från testresultaten bestämdes de virtuella fordonsfunktionerna. Vidare har i den andra delen av rapporten ett exempel på användningsfall beaktats genom att man tar två kalibreringsuppsättningar av ESC-system (Electronic Stability Control) för att verifiera det tidigare etablerade ramverket.Analysen innefattar olika nivåer av modell- och styrenhetskomplexitet såsom Model-in-loop, Software-in-loop och Hardware-in-loop och på två olika vägytor, låg friktion och hög friktion. Enligt observationerna är de virtuella modellerna väl korrelerade för verifiering och validering. För kalibreringen måste dock modellerna finjusteras på den virtuella plattformen. Dessutom kunde korrelationen på lågfriktionsvägytan förbättras genom att simulera testerna med hjälp av en avancerad däckmodell. Sammantaget hjälper den här studien att välja rätt komplexitet hos olika delsystem i ett fordon för verifiering, validering och kalibrering av fordonets rörelsekontrollfunktioner.

Racing drivers always want to traverse path at vehicle’s maximum performance limits while keeping the vehicle at its ideal trajectory. The main objective of this report is to elaborate strategy for the path following problem in which driver has to follow the predefined 2D roads. New steering controller design for closed loop racing driver model in Dymola vehicle dynamics library is developed. The methodology proposed by Sharp et al. [2] is followed with the optimal velocity profile that tries to mimic the actions of the real drivers in real time scenarios. Vehicle handling limits i.e. longitudinal and lateral limits are defined before simulation. While travelling in the neighbourhood of optimal velocity on the straight road as well as during the curves, the performance of the steering controller is tested by conducting the test on J turn, Clothoid, Extended chicane and the closing curve path and also tested during the different environment effects e.g. when there is a side wind affecting the vehicle. Performance of existing and new steering controllers discussed and compared in result chapter. It is ensured that the drawbacks in the existing steering controller are eliminated by using the proposed methodology in new implemented steering controller. Key Words: Driver Model, Steering Controller, Path following, Velocity profile

International Telemetering Conference Proceedings / October 26-29, 1992 / Town and Country Hotel and Convention Center, San Diego, California / Some Telemetry systems today receive a binary phase shift keying modulation format. Typically, to demodulate BPSK requires using a carrier synchronizer followed by a bit synchronizer. Demodulation of BPSK can be accomplished using digital signal processing techniques to implement both synchronizers. This paper describes a digital system that demodulates a 16 KHZ, 2KBPS BPSK signal. In order to evaluate these techniques, the theory of operation was evaluated. Additionally, a computer simulation of the demodulator was developed. The computer simulation was implemented using Pascal. The techniques were optimized to give maximum performance while requiring minimum hardware and power in an actual implementation.