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Chamanirad, Mohsen. "Design and implementation of controller for robotic manipulators using Artificial Neural Networks." Thesis, Mälardalen University, School of Innovation, Design and Engineering, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-6297.
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In this thesis a novel method for controlling a manipulator with arbitrary number of Degrees of freedom is proposed, the proposed method has the main advantages of two common controllers, the simplicity of PID controller and the robustness and accuracy of adaptive controller. The controller architecture is based on an Artificial Neural Network (ANN) and a PID controller.
The controller has the ability of solving inverse dynamics and inverse kinematics of robot with two separate Artificial Neural Networks. Since the ANN is learning the system parameters by itself the structure of controller can easily be changed to
improve the performance of robot.
The proposed controller can be implemented on a FPGA board to control the robot in real-time or the response of the ANN can be calculated offline and be reconstructed by controller using a lookup table. Error between the desired trajectory path and the path of the robot converges to zero rapidly and as the robot performs its tasks the controller learns the robot parameters and generates better control signal. The performance of controller is tested in simulation and on a real manipulator with satisfactory results.
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Thomas, Philip S. "A Reinforcement Learning Controller for Functional Electrical Stimulation of a Human Arm." Case Western Reserve University School of Graduate Studies / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=case1246922202.
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Chang, Jen. "Hydrodynamic modeling and feasibility study of harnessing tidal power at the Bay of Fundy." View ebook online, 2008. http://digitallibrary.usc.edu/assetserver/controller/item/etd-Chang-20080312.pdf.
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MacGregor, Scott D. "A fault tolerant transportation controller." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/43482.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1997.Includes bibliographical references (leaf 66).
by Scott D. MacGregor.
M.Eng.
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Pakalapati, Lalita Varma V. (Lalita Varma Venkata) 1976. "Controlled release microchip." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/7976.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2003.Includes bibliographical references (leaf 34).
Microchips for constant release are not a new concept, but a controlled release chip, which does pulsatile release at variable time intervals, is clearly more efficient and useful. The process was completely understood about the theory of operation, the manufacturing procedure and the robustness of the controlled release microchip. The complete application analysis has been done along with the intellectual property study. The study involved finding out the industry opinion of the device and the usefulness of the device and all the people who might have intellectual property rights in the field. As a result numerous applications of the device have been found out along with the important parameters the device should be concentrating on have been suggested.
by Lalita Varma V. Pakalapati.
M.Eng.
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Samadi, Khah Pouya. "Performance Modeling of OpenStack Controller." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-195649.
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OpenStack is currently the most popular open source platform for Infrastructure as a Service (IaaS) clouds. OpenStack lets users deploy virtual machines and other instances, which handle different tasks for managing a cloud environment on the fly. A lot of cloud platform offerings, including the Ericsson Cloud System, are based on OpenStack. Despite the popularity of OpenStack, there is currently a limited understanding of how much resource is consumed/needed by components of OpenStack under different operating conditions such as number of compute nodes, number of running VMs, the number of users and the rate of requests to the various services. The master thesis attempts to model the resource demand of the various components of OpenStack in function of different operating condition, identify correlations and evaluate how accurate the predictions are. For this purpose, a physical OpenStack is setup with one strong controller node and eight compute nodes. All the experiments and measurements were on virtual OpenStack components on top of the main physical one. In conclusion, a simple model is generated for idle behavior of OpenStack, starting and stopping a Virtual Machine (VM) API calls which predicts the total CPU utilization based on the number of Compute Nodes and VMs.
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Raissi, Dehkordi Vahid. "Managing uncertainty in robust controller implementation." Thesis, McGill University, 2011. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=103536.
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For a linear time-invariant (LTI) plant, a robust controller is often designed in order to maintain robust stability and performance of the system. In robust controller implementation, two problems might arise. First, it is interesting to know whether it is possible to simplify the controller and to what degree before its implementation while still maintaining system robust performance. The second concern arises in real-time applications where the controller may have to be retuned or redesigned several times after the initial implementation stage. In both problems, it is important to know how much a modified controller can deviate from the originally designed one in the frequency domain. The robust controller deviation is modeled as the controller uncertainty just like any other uncertainty with its own unique weighting function. A necessary and sufficient condition for robust performance as well as a sufficient condition is derived in the form of bounds on the magnitude of maximum deviation of the robust controller over a grid of frequency samples for a single-input single-output (SISO) structure. The multi-input multi-output (MIMO) case is also addressed by providing an upper bound on the maximum singular value of the system's frequency response derived at individual frequency samples, leading to a sufficient condition for robust performance. The above bounds are used in conjunction with the balanced truncation technique in order to determine how much the order of a robust controller can be reduced without losing robust performance. The order reduction limit is expressed as the maximum number of states that can be removed in a state-space realization of the robust controller for both SISO and MIMO system structures, without actually having to reduce the order. Finally, a practical approach is proposed in order to derive a robust internal model (IMC) controller for an SISO system structure. The ideal robust IMC controller is already provided as a function of the frequency response of all system components at every frequency sample. It is then approximated with a stable and preferably low order system while maintaining robust performance in three steps - the inverse fast Fourier transform (IFFT), the finite impulse response (FIR) approximation, and the FIR-to-IIR (infinite impulse response) conversion.Un contrôleur robuste est souvent conçu afin de maintenir la stabilité et la performance robuste d'un système linéaire invariant dans le temps. Durant l'implantation d'un tel contrôleur, deux problèmes se présentent. Premièrement, il est intéressant de savoir s'il est possible de simplifier le contrôleur robuste et si oui, jusqu'à quel point avant de l'implanter, tout en garantissant la performance robuste. Le deuxième problème se pose dans les applications à temps réel où le contrôleur devrait être refait ou ajusté plusieurs fois après la mise en service initiale. Il est important de savoir, concernant les deux problèmes ci-dessus, jusqu'à quel point le contrôleur modifié peut s'éloigner de l'original dans le domaine des fréquences. Une condition suffisante et nécessaire pour la performance robuste ainsi qu'une condition suffisante sont dérivées sous forme de limites sur le module de la déviation maximum du contrôleur robuste sur une grille de fréquences pour un système à sortie unique et à entrée unique (SISO). Le cas d'entrées et sorties multiples (MIMO) est aussi traité en fournissant une limite sur la valeur singulière maximum de la réponse en fréquence du système calculée à chaque point de fréquence, formant une condition suffisante pour la performance robuste. Les limites ci-dessus sont utilisées avec la technique de réduction équilibrée (balanced truncation) afin de déterminer à quel point il est possible de réduire l'ordre du contrôleur sans perdre la performance robuste. Le nombre maximum d'états du contrôleur admissibles pour l'élimination est donné, sans vraiment devoir le modifier. Finalement, une méthode pratique est proposée pour réaliser un contrôleur robuste basé sur la commande par modèle interne (IMC) pour un système SISO. La réponse en fréquence du contrôleur robuste idéal est déjà fournie comme une fonction de la réponse en fréquence de toutes les composantes de système. Puis, le contrôleur idéal est approximé par un système stable et préférablement d'ordre peu élevé en gardant la performance robuste aux trois étapes : transformation inverse de Fourier rapide (IFFT), approximation par un système de réponse impulsionnelle finie (FIR) et conversion de FIR à réponse impulsionnelle infinie (IIR).
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Bhuta, Dimple. "Brain Controlled Switch." VCU Scholars Compass, 2012. http://scholarscompass.vcu.edu/etd/2795.
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This study aims at designing and implementing a single channel stand-alone Brain-Controlled Switch (BCS) device, which records the electroencephalography (EEG) signals from the scalp using electrodes, amplifies it, eliminates interferences (associated with the EEG signals) and processes the EEG signals to extract and decode temporal signal features to determine user’s intention of regulating an external switch. The design of our “brain-controlled switch” device is implemented using a bio-potential amplifier and a microcontroller. The bio-potential amplifier amplifies the EEG signals to a level sufficient for processing, eliminates interferences and ensures patient safety. The microcontroller (dsPIC30F4013) digitizes the amplified and conditioned analog EEG signals from the bio-potential amplifier, extracts the desired signal features for decoding and prediction of user’s intention and accordingly operates the external switch. When the user concentrates on an external visual stimulus or performs externally triggered movement (hand movement or motor imagery movement), a reproducible pattern appears in user’s EEG frequency bands. The analysis of these patterns is used to decode and predict user’s intention to operate an external switch. To realize our “brain-controlled switch”, we explored two EEG sources: steady-state visually evoked potentials (SSVEP) and beta rebounds, which are patterns generated in the EEG frequency bands associated with focusing on an external visual stimulus or performing externally triggered movements. In case of SSVEP based brain controlled switch, a repetitive visual stimulus (LED flickering at a specified frequency) was used. When the user concentrates on the flickering LED, a dominant fundamental frequency (equivalent to the flickering frequency) appears in the spectral representation of the EEG signals recorded at occipital lobes. Our microcontroller implemented a digital band pass filter to extract the frequency band containing this fundamental frequency and continuously took an average of the amplitude power every predetermined time interval. Whenever the amplitude average power exceeded the preset power threshold the external switch was turned ON. A healthy subject participated in this study, and it took approximately 3.14 ± 1.81 seconds of active concentration for the subject to turn ON the switch in real time with a false positive rate of 1.17%. In case of beta rebound based brain controlled switch, the subject was instructed to perform a brisk hand movement following an external synchronization signal. Our design focused on the post-movement beta rebound which occurs after the cessation of the movement to operate the external switch. Our microcontroller in this case implemented a digital band pass filter to extract the beta band and continuously took an average of its amplitude power every predetermined time interval. Whenever the amplitude average power exceeded the preset power threshold the external switch was turned ON. It took approximately 12.23 ± 7.39 seconds of active urging time by the subject to turn ON the switch in real time with a false positive rate of 9.33%. Thus we have designed a novel stand-alone BCS device which operates an external switch by decoding and predicting user’s intentions.
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Buyukkeles, Umit. "Improved Torque And Speed Control Performance In A Vector-controlled Pwm-vsi Fed Surface-mounted Pmsm Drive With Conventional P-i Controllers." Master's thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12614294/index.pdf.
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In this thesis, high performance torque and speed control for a surface-mounted permanent magnet synchronous machine (PMSM) is designed, simulated and implemented. A three-phase two-level pulse width modulation voltage-source inverter (PWM-VSI) with power MOSFETs is used to feed the PMSM.
The study has three objectives. The first is to compensate the voltage disturbance caused by nonideal characteristics of the voltage-source inverter (VSI). The second is to decouple the coupled variables in the synchronous reference frame model of the PMSM. The last is to design a load torque estimator in order to increase the disturbance rejection capability of the speed control. The angular acceleration required for load torque estimation is extracted through a Kalman filter from noisy velocity measurements.
Proposed methods for improved torque and speed control performance are verified through simulations and experimental tests. The drive system is modeled in Matlab/Simulink, and control algorithms are developed based on this model. The experimental drive system comprises a three-phase VSI and a 385 W surface-mounted PMSM. Control algorithms developed in the study have been implemented in a digital signal processor (DSP) board and tested comprehensively. With the use of the proposed methods, a considerable improvement of torque and speed control performance has been achieved.
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Francisco, Denilson de Oliveira. "Manutenção de modelos para controladores preditivos industriais." reponame:Biblioteca Digital de Teses e Dissertações da UFRGS, 2017. http://hdl.handle.net/10183/171396.
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O escopo desta dissertação é o desenvolvimento de uma metodologia para identificar os modelos de canais da matriz dinâmica que estejam degradando o desempenho de controladores preditivos, ou MPC (Model Predictive Control), baseado nas técnicas de auditoria e diagnóstico deste tipo de controlador propostas por BOTELHO et al. (2015) e BOTELHO; TRIERWEILER; FARENZENA (2016) e CLARO (2016). A metodologia desenvolvida contempla dois métodos distintos. O primeiro, chamado método direto compensado, tem como base o método direto de identificação em malha fechada (LJUNG, 1987)e compensa cada saída medida do processo de modo a se reter apenas a contribuição do canal que se deseja identificar. O segundo, chamado método do erro nominal, utiliza a definição de saída nominal do processo, proposta por BOTELHO et al. (2015), como métrica para se quantificar o quão próximo o modelo está do comportamento da planta através da minimização do erro nominal. Os métodos foram aplicados ao sistema de quatro tanques cilíndricos (JOHANSSON, 2000) para dois cenários distintos, sendo o primeiro um sistema 2x2 em fase não mínima contendo um MPC trabalhando com setpoint e o segundo um sistema 4x4 em fase mínima com o MPC atuando por faixas. Para o sistema 2x2, se avaliou a influência da localização do canal discrepante (dentro ou fora da diagonal principal da matriz dinâmica de transferência) na eficácia dos métodos. Para o sistema 4x4, o estudo foi voltado para a eficácia dos métodos frentes a controladores que atuam dentro de limites para as variáveis. Os modelos identificados foram comparados pela capacidade de identificar um modelo que capturasse o zero de transmissão da planta e o RGA dinâmico, par ao sistema 2x2, e pelas respostas degrau e diagrama de Bode para o sistema 4x4. O método direto compensado resultou em baixo erro relativo no valor do zero para a discrepância na diagonal principal da matriz dinâmica e alto valor quando a discrepância se encontrava fora da diagonal principal. O método do erro nominal, por sua vez, foi capaz de identificar um modelo cujo zero de transmissão possuía baixo erro relativo frente ao zero da planta em ambos os cenários. No cenário do controlador atuando por faixas, os métodos propostos obtiveram melhores estimativas dos modelos quando comparados com o método concorrente, uma vez que apresentou alto percentual de aderência das saídas simuladas com as saídas medidas. Em todos os cenários estudados, o método do erro nominal se mostrou capaz de identificar um modelo mais robusto, pois este apresentou RGA dinâmico compatível com a planta em todo o range de frequências analisado.The objective of this dissertation is to develop a method to identify the model for the channel of the dynamic matrix that are affecting the performance of model predictive controllers (MPC), based on the assessment and diagnosis techniques for this type of controller proposed by BOTELHO et al. (2015) e BOTELHO; TRIERWEILER; FARENZENA (2016) and CLARO (2016). The proposed methodology includes two different methods. The first, called the compensated direct method, is based on the closed-loop direct identification method (LJUNG, 1987) and compensates each process measured output in order to retain only the contribution of the channel being identified. The second, called nominal error method, uses the definition of the process nominal output, proposed by BOTELHO et al. (2015), as a metric to quantify how close the model is to the actual plant behavior by minimizing the nominal error. The proposed methods were applied to the quadruple-tank system (JOHANSSON, 2000) for two distinct scenarios, the first being a nonminimum-phase 2x2 system containing a MPC working with setpoint and the second a minimum-phase 4x4 system with the MPC working by ranges. For the 2x2 system, the influence of the model mismatch location (inside or outside the main diagonal of the dynamic transfer matrix) on the effectiveness of the methods was evaluated. For the 4x4 system, the study was focused on the effectiveness of the methods with controllers that operate within limits for the variables. The identified models were compared by the capability of identifying a model with accurate plant transmission zero and dynamic RGA, for the 2x2 system, and by the step responses and Bode diagram for the 4x4 system. The compensated direct method resulted in low relative error in the value of the transmission zero for the model mismatch located in the main diagonal of the dynamic matrix and high relative error when the mismatch was outside the main diagonal. On the other hand, the nominal error method was able to identify a model whose transmission zero had low relative error against the plant zero in both scenarios. In the scenario of a controller working by range, the proposed methods obtained better estimates of the models when compared to the concurrent method, since it presented a high percentage of adherence of the simulated outputs with the measured outputs. In all the studied scenarios, the nominal error method was able to identify a more robust model, since it presented dynamic RGA compatible with the plant in the entire range of analyzed frequencies.
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Maloney, John Mapes. "Electrothermal controlled-exposure technology." Thesis, Massachusetts Institute of Technology, 2006. http://hdl.handle.net/1721.1/37355.
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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2006.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (p. 73-79).
A technology is presented for exposing the contents of microfabricated cavities in a substrate. These contents are hermetically sealed until exposure is triggered by an electronic signal. The exposure mechanism uses electrothermal heating to rupture a metal membrane at one end of the cavity. The device's capability for storing a variety of contents and exposing them on demand makes it well suited for periodic exposure of new sensors as old ones degrade. Two commercialization possibilities are investigated: biowarfare agent detection and in vivo glucose sensing. Both applications employ sensing mechanisms that can be miniaturized and packaged in an array. These sensors are susceptible to fouling or degradation over time from environmental factors. The controlled-exposure technology addresses this problem by periodically exposing fresh sensors. The two applications are thought to be especially favorable markets because of the need for reliable, continuous sensing. The engineering aspects of the technology are investigated by identifying key material properties for each component of the device.
(cont.) The key properties for the substrate material are suggested to be its vapor permeability and suitability for cavity formation. The most important properties of the membrane are its electrical requirements (the current and voltage required to expose or "activate" the device), its strength and hermeticity, and its stability in the intended working environment. Design and materials selection approaches for optimizing these properties are presented.
by John Mapes Maloney.
M.Eng.
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Sachs, David Matthew. "A forearm controller and tactile display." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/33891.
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Thesis (S.M.)--Massachusetts Institute of Technology, School of Architecture and Planning, Program in Media Arts and Sciences, 2005.Includes bibliographical references (leaves 187-192).
This thesis discusses the design and implementation of ARMadillo, a simple virtual environment interface in the form of a small wireless device that is worn on the forearm. Designed to be portable, intuitive, and low cost, the device tracks the orientation of the arm with accelerometers, magnetic field sensors, and gyroscopes, fusing the data with a quaternion based Unscented Kalman Filter. The orientation estimate is mapped to a virtual space that is perceived through a tactile display containing an array of vibrating motors. The controller is driven with an 8051 microcontroller, and includes a BlueTooth module and an extension slot for CompactFlash cards. The device was designed to be simple and modular, and can support a variety of interesting applications, some of which were implemented and will be discussed. These fall into two main classes. The first is a set of artistic applications, represented by a suite of virtual musical instruments that can be played with arm movements and felt through the tactile display, The second class involves utilitarian applications, including a custom Braille-like system called Arm Braille, and tactile guidance. A wearable Braille display intended to be used for reading navigational signs and text messages was tested on two sight-impaired subjects who were able to recognize Braille characters reliably after 25 minutes of training, and read words by the end of an hour.
by David Matthew Sachs.
S.M.
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Grefe, William Kevin. "Integrating Collision Avoidance, Lane Keeping, and Cruise Control With an Optimal Controller and Fuzzy Controller." Thesis, Virginia Tech, 2005. http://hdl.handle.net/10919/32142.
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This thesis presents collision avoidance integrated with lane keeping and adaptive cruise control for a car. Collision avoidance is the ability to avoid obstacles that are in the vehicleâ s path, without causing damage to the obstacle or car. There are three types of collision avoidance controllers, passive, active, and semi-active. This thesis is designed using active collision avoidance controllers.
There are two controllers developed for collision avoidance in this paper. They are an optimal controller and a fuzzy controller. The optimal vehicle trajectory, which maximizes the distance to an obstacle and changes lanes, is derived. The optimal collision avoidance controller is a closed loop controller; with the decisions based on the current state. The fuzzy controller makes decisions based on the system rules. A simulation environment was created to compare these two controllers as viable solutions for collision avoidance.
The environment uses MATLAB/Simulink for simulation of the vehicle as well as the optimal and fuzzy controllers. The simulation incorporates system blocks of the kinematics of a car, navigation, states, control law, and velocity controller. Once the controllers are fully developed and tested in the simulation environment, they are implemented and tested on the platform vehicle. This verifies the real world performance of the controllers.
The platform vehicle is a modified radio controlled car. This car is completely autonomous. The car has onboard sensors that allow it to follow a white piece of tape as well as detect obstacles.
Master of Science
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Ardinugroho, Servatius Bismanditio. "Implementation and Tuning of PID, Fractional PID and LA Controllers for pH Control." Thesis, Université d'Ottawa / University of Ottawa, 2019. http://hdl.handle.net/10393/38747.
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Maintaining the pH of a fluid or a solution at a specific value is a concern in many industrial processes, wastewater management, and food and pharmaceutical production. Given the importance of controlling pH in many processes, the objective of this thesis is to study and compare the effectiveness of some controller algorithms to control the pH of a process. In this study, the performance of three controller algorithms, namely PID, fractional PID and LA controllers, is evaluated for the control of a simple neutralization process using conventional controller performance metrics. Performance metrics used are the response time, the Integral of the Time weighted Absolute Error (ITAE), the Integral of the Squared Error (ISE), and the Integral of the Squares of the changes (ΔU) in the manipulated variable (ISDU). The three controllers were therefore tuned to minimize one or a combination of the controller performance metrics. Results show that PID, fractional PID and LA controllers implemented and tested in this research are all worthy controllers for maintaining pH of the neutralization process. Simulation results show that the three controllers can be used with confidence to cope with the high nonlinearity of a pH neutralization process provided that the process is properly designed. The relative small gain in performance obtained with the fractional PID controller, compared to a linear PID controller, suggests that it is not worth resorting to a fractional PID controller given its complexity and higher computation effort. Results show that PID and LA controllers are easy to implement with short response time and low ITAE and ISDU performance metrics.
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GarcÃa, Z. Yohn E. "Fuzzy logic in process control: A new fuzzy logic controller and an improved fuzzy-internal model controller." Scholar Commons, 2006. http://scholarcommons.usf.edu/etd/2529.
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Two fuzzy controllers are presented. A fuzzy controller with intermediate variable designed for cascade control purposes is presented as the FCIV controller. An intermediate variable and a new set of fuzzy logic rules are added to a conventional Fuzzy Logic Controller (FLC) to build the Fuzzy Controller with Intermediate Variable (FCIV). The new controller was tested in the control of a nonlinear chemical process, and its performance was compared to several other controllers. The FCIV shows the best control performance regarding stability and robustness. The new controller also has an acceptable performance when noise is added to the sensor signal. An optimization program has been used to determine the optimum tuning parameters for all controllers to control a chemical process. This program allows obtaining the tuning parameters for a minimum IAE (Integral absolute of the error). The second controller presented uses fuzzy logic to improve the performance of the convention
al internal model controller (IMC). This controller is called FAIMCr (Fuzzy Adaptive Internal Model Controller). Twofuzzy modules plus a filter tuning equation are added to the conventional IMC to achieve the objective. The first fuzzy module, the IMCFAM, determines the process parameters changes. The second fuzzy module, the IMCFF, provides stability to the control system, and a tuning equation is developed for the filter time constant based on the process parameters. The results show the FAIMCr providing a robust response and overcoming stability problems. Adding noise to the sensor signal does not affect the performance of the FAIMC.The contributions presented in this work include:The development of a fuzzy controller with intermediate variable for cascade control purposes. An adaptive model controller which uses fuzzy logic to predict the process parameters changes for the IMC controller. An IMC filter tuning equation to update the filter time constant based in the process paramete
rs values. A variable fuzzy filter for the internal model controller (IMC) useful to provide stability to the control system.
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Saraswat, Anant K. (Anant Kumar) 1981. "An interrupt controller for the RAW processor." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/87889.
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Liu, Ming Gang. "BlueFlash : a reconfigurable flash controller for BlueDBM." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/92962.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2014.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 55-58).
NAND flash has risen to become a popular storage medium in recent years due to its significant bandwidth, access latency and power advantages over traditional hard disks. However, in modern Big Data systems, simply replacing disks with flash does not yield proportional performance gains. This is because of bottlenecks in various levels of the system stack: I/O interface, network, file system and processor. Introduced in 2012, BlueDBM is a novel Big Data flash storage platform that includes a dedicated low latency sideband storage network between flash controllers, reconfigurable fabric for implementing in-store hardware accelerators and a flash-aware file system. While results are promising, the original BlueDBM platform used old flash boards that were merely 16GB in capacity running at 80MB/s. This work presents BlueFlash, a revamped and improved storage device for the BlueDBM platform. We present the design of a new 0.5TB flash board, a new ONFI-compliant FPGA-based flash controller with ECC and we explore the characteristics of the flash board. We demonstrate that BlueFlash scales well with multiple buses and multiple chips per bus, reaching 1.2GB/s (75% of theoretical max) read and 1.0GB/s (91% theoretical max) write bandwidth while consuming only 6W of power.
by Ming Gang Liu.
S.M.
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Barbour, John D. (John David). "The execution of a video editing controller." Thesis, Massachusetts Institute of Technology, 1986. http://hdl.handle.net/1721.1/14900.
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Thesis (B.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1986.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING.
by John D. Barbour.
B.S.
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Masters, Brett P. (Brett Peter). "Evolutionary design of controlled structures." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/50302.
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Lee, Vanessa Sharon. "Aboriginal Community Controlled Health Services: Controlled or Controlling their own Destinies?" Thesis, Griffith University, 2016. http://hdl.handle.net/10072/367501.
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The Indigenous people in Australia are the Aboriginal and Torres Strait Islanders. Since colonisation in 1788 this population has diminished significantly. Following years of advocacy addressing inequitable government policies towards Aboriginal and Torres Strait Islanders, the first Aboriginal Medical Service was established in Redfern, New South Wales, in 1971. From this one Aboriginal Medical Service there grew many more across Australia; in some jurisdictions they are referred to as Aboriginal Community Controlled Health Services (ACCHS). This study was designed to examine the bureaucratic and organisational structures, functions and operations of these ACCHS, and how these services meet both the organisation’s requirements and the community’s expectations when delivering a culturally-appropriate health service to Aboriginal and Torres Strait Islander people.
This research applies a case study method within a qualitative paradigm for the depth needed to explore the research aims. Following discussions with the Queensland Aboriginal and Islander Health Council, the sites for this research were identified in central and southern Queensland. The three sites were vastly separated by distance but at the same time subjected to similar historical abuse. The participants drawn from these sites were Aboriginal and Torres Strait Islanders and the research attempted to capture their perceptions. Each case was subjected to a conceptual and thematic analysis to draw out the key themes and concepts and thence to develop a theoretical model of how the ACCHS balance their organisational requirements and community expectations.Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Medical Science
Griffith Health
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Klinker, Michael R. "Tethered UAV Flight using a spherical position controller." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/105620.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Aeronautics and Astronautics, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 143-144).
In recent years, the aerospace community has seen a rise in the popularity of multirotor unmanned aircraft. This increase in popularity is in part due to the ability of a multirotor aircraft to hover, its simple dynamics, and its mechanical simplicity. Operating these unmanned aircraft indoors or outdoors is a well understood challenge, however these aircraft have predominantly been operated in an unconstrained area. This thesis investigates how to control a multirotor aircraft in a constrained environment, such as on the end of a tether. A position controller is presented for a multirotor UAV operating on the end of a fixed length, tensioned tether in spherical coordinates, which utilizes the vehicles relative position and tether dynamics to calculate control inputs and ensure flight stability. The proposed position controller was put through a series of verification and validation tests using both a simulated tether-aircraft system, as well as a quadrotor flown in the RAVEN indoor flight space in the MIT Aerospace Controls Laboratory. During simulated flight testing the spherical position controller showed a 35.7% decrease in tether tension, and during indoor flight testing the spherical position controller exhibited an 8.4% decrease in power consumption over the traditional Cartesian position controller while operating on the end of a fixed length tether.
by Michael R. Klinker.
S.M.
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Yadav, Vikas. "Distributed controller synthesis and decision making." [Ames, Iowa : Iowa State University], 2007.
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Newman, Mark. "Expertise and the air traffic controller." Thesis, Cardiff University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.400448.
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Tamm, Steven L. (Steven Lawrence). "Magnbots : actively controlled magnetic robots." Thesis, Massachusetts Institute of Technology, 1997. http://hdl.handle.net/1721.1/43507.
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Lee, Kevin Shao-Kwan. "Microscale controlled continuous cell culture." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/64579.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2011.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 489-500).
Measurements of metabolic and cellular activity through substrate and product interactions are highly dependent on environmental conditions and cellular metabolic state. For such experiments to be feasible, continuous cultures are utilized to ensure consistent conditions. However, since medium must be replenished every cell doubling time, costs can be prohibitive in large reactors. An integrated microscale bioreactor with built-in fluid metering and environmental control will enable programmed experiments capable of generating reproducible data routinely. This work develops an instrument capable of supporting automated microscale continuous culture experiments. The instrument consists of a plastic-PDMS device capable of continuous flow reactions without volume drift. A novel bonding process is invented to fabricate devices with chemically stable interfaces against water, acids, and bases. We introduce a direct CNC machining and chemical bonding fabrication process for production of fluidic devices with a 1 mL working volume, high oxygen transfer rate (kLa ~ 0.025 s-1), fast mixing (2 s), accurate flow control (± 18 nL), and closed loop control over temperature, cell density, oxygen, and pH. Providing control over environmental parameters allows the system to perform different types of cell culture on a single device, such as batch, fed-batch, chemostat, and turbidostat continuous culture. Validation experiments demonstrate that cells can be grown to high optical densities (OD = 50) and production of commercially relevant chemicals such as DNA vaccines are comparable to large scale bench fermentations. Continuous cultures are also demonstrated without contamination for 3 weeks in a single device and both steady state and dynamically controlled conditions are possible, allowing observations of cell metabolic dynamics.
by Kevin Shao-Kwan Lee.
Ph.D.
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Topper, Anthony. "A computing architecture for a multiple robot controller /." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60484.
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This thesis describes the architecture of the Kali multi-arm robot control system, including discussions on design trade-offs and performance, as well as a detailed implementation using off-the-shelf hardware and software. Kali's main objectives are flexibility, integration, and hardware and software modularity so as to facilitate programming, experimentation and portability. It is used primarily to prototype concepts in multi-arm coordination, teleoperation, force control, and sensor fusion etc. To implement Kali requires only a minimal real-time kernel, a sufficiently powerful computer and a robot interface. It is based on the principle that, today, computational hardware, real-time operating systems and robot interfaces no longer impede robot controller design. Rather it is control software and system integration which are now the main problems. To that end, this work also discusses in depth the fundamental problems in the design and engineering of robot controllers from an implementational point of view using Kali as a primary design example.
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Risan, Jared. "Method for Compliance Controlled Adhesive Switching and Magnetically Controlled Switchable Adhesives." Thesis, North Dakota State University, 2013. https://hdl.handle.net/10365/26990.
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Adhesives are used in a variety of ways and are so common that they are easily overlooked. Adhesive hooks, tapes, glues, and switchable climbing mechanisms used by insects and lizards are clear examples of how adhesives are beneficial to society and nature. The development of novel switchable adhesives is a research area that is largely incomplete. In fact, very few switchable adhesives exist on the market today; hence their development would tremendously impact the adhesive industry. This thesis studies a mechanism for stiffness controlled switchable adhesion by utilizing a magnetically switchable device. The influence of nanopowder reinforcement on the compliance of polymeric-metallic composite switchable adhesives is investigated. Highly compliant composites are switched by magnetic and mechanical clamping leading to changes in compliance and adhesion. Material characterization is done with lap-shear testing while effects of reinforcement and clamping methods are studied. Ultimately, magnetic switching is consistent with a simple mechanical model.
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Tchapmi, Petse Lyne. "Wide-bandwidth digital controller for multi-phase converters." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/100672.
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Thesis: M. Eng., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2014.Cataloged from PDF version of thesis.
Includes bibliographical references (page 63).
DC-DC converters with high bandwidth are essential for today's high efficiency and high-speed micro-processing applications. In order to satisfy the requirements of those systems, we propose the implementation of a practical wide bandwidth digital controller for multiphase buck converters. Traditional implementations of multiphase converters have a performance comparable to single-phase implementations, with a bandwidth limited to a fraction of the per-phase switching frequency Fsw. The goal of this project is to take advantage of multiphase to achieve a higher bandwidth for any given switching frequency. Specifically, we target a bandwidth that scales with N x Fsw, rather than Fsw, with N being the number of phases in the system. This work focuses on the evaluation of a previously proposed digital modulator that is able to react to duty cycle changes at a speed equal to N x Fsw. Using this modulator, we design a few digital controllers and compare their performance to that of traditional digital controllers.
by Lyne Petse Tchapmi.
M. Eng.
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Brooks, Lane Gearle 1975. "Amplitude and frequency demodulation controller for MEMS accelerometer." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/8938.
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Thesis (M.Eng. and S.B.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.Includes bibliographical references (p. 121-122).
Draper Laboratory is developing a high precision MEMS accelerometer. This thesis describes and analyzes the electronics which produce the acceleration estimate and control the actuators within the sensor. The Vector Readout method of amplitude and frequency demodulation is described and shown to be a high precision, environmentally stable method of demodulation. The Vector Readout method of demodulation uses a Hilbert Transform filter and the CORDIC algorithm to simultaneously estimate both the amplitude and phase of a signal. A feedback controller is designed to hold the oscillation of a mass resonator at a constant amplitude.
by Lane Gearle Brooks.
M.Eng.and S.B.
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Holmberg, Anthony, and Nils Lundqvist. "WoodWinder : MIDI Controlled Recorder." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264499.
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WoodWinder is a machine whose job is to interpret the signal from a Musical Instrument Digital Interface (MIDI) keyboard and make a recorder play accordingly. This was performed by simulating the two human traits needed in order to play the recorder: providing air flow for the mouthpiece and fingers to cover its holes. The air flow was provided by a custom made centrifugal fan and directed through a separation chamber which determined how much air was allowed to travel through the mouthpiece and how much was driven out through an exhaust. The purpose of the separation chamber was to simulate the amplitude of the played tone. The movement of the fingers was enabled by seven servo motors, mounted collaterally to the recorder. All movement was governed by two Arduino Microcontroller Units (MCU), a servo driver and a motor driver. The machine can play any note on demand without hardly any noticeable lag. The two lowest tones D and C were somewhat limited as they produced a distorted sound at high enough velocities. The largest error in accuracy for expected frequencies was around 6Hz.WoodWinder är en maskin vars jobb är att tolka signalen från ett MIDI keyboard och få en blockflöjt att spela efter. Detta utförs genom att simulera de två mänskliga egenskaperna som krävs just för att spela en blockflöjt: förmedla luftflöde till munstycket och fingrar till att täcka hålen. Luftflödet förmedlades via en specialtillverkad centrifugalfläkt och fördes genom en separationskammare som bestämde hur mycket luft som tilläts flöda in i munstycket kontra ut ur en ventil. Detta för att bäst simulera amplituden på tonen som spelades. Fingrarnas rörelse möjliggjordes av sju servomotorer, monterade längs blockflöjten och all rörelse styrdes av två Arduino-mikrokontroller, en servooch en motordrivare. Maskinen kan spela alla tänkta toner utan någon märkbar fördröjning. De två lägsta tonerna D och C blev något begränsade då de, vid högt luftflöde, producerade ett något förvrängt ljud. Det största uppmätta felet i förhållande till förväntade värden var 6Hz.
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Mwinyiwiwa, Bakari M. M. "Some methodologies for facts controllers." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ37008.pdf.
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Henry, Jason Matthew. "Theory and implementation of the naturally transitioning rate-to-force controller including force reflection using kinematically dissimilar master/slave devices." Ohio : Ohio University, 1999. http://www.ohiolink.edu/etd/view.cgi?ohiou1175879099.
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Junior, Dionizio Paschoareli. "Modelling and implementation of a unified voltage controller : an alternative FACTS controller to improve power transfer." Thesis, University of Aberdeen, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.301204.
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In the last years, the planning of optimised electric power systems, in addition to a more efficient operation of already installed systems, has resulted in an appealing development of controllers which make transmission systems more flexible. The acronym FACTS (Flexible AC Transmission Systems) has become a synonym of electronic-based controllers that perform a quick and safe control of system parameters. A large number of FACTS controllers have been proposed, most of them already in operation. The construction of a comprehensive controller, which would provide simultaneous control of several system parameters at a reduced cost and size, has been the challenge addressed to power engineering designers. This thesis presents the Unified Voltage Controller (UVC), which is an alternative to the control of power flow. The UVC is based on the control of local and remote voltage vectors of the transmission line ends. The concept of the parameters involved in power transfer is discussed. Equations of space vector control for the UVC are defined, and the pulse-width modulation to control the UVC converters is presented. A simplified three-phase system is simulated to show the efficacy of the UVC when operating as a conditioner of power systems. Several simulations have been developed to show the efficiency of the UVC. The control of the local and the remote voltage magnitude, besides the control of transmission angle have been illustrated through computational simulation.
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Zhao, Yang. "Applications of Sliding Mode Controller and Linear Active Disturbance Rejection Controller to a PMSM Speed System." Cleveland State University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=csu1374239996.
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La, Rocca Peter. "A multivariable controller for an electromagnetic bearing/shaft system." Thesis, Massachusetts Institute of Technology, 1988. http://hdl.handle.net/1721.1/35341.
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Livadas, Carolos. "Optimal H₂/Popov controller design using linear matrix inequalities." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/49613.
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Violette, James D. (James Douglas). "Implementation of a hierarchical controller in a factory simulation." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/47327.
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Craig, Ian Keith. "Sensitivity of H[infinity] controller designs to structured uncertainty." Thesis, Massachusetts Institute of Technology, 1989. http://hdl.handle.net/1721.1/39034.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 1989.On t.p., "[infinity]" appears as the mathematical sign for infinity.
Includes bibliographical references (leaves 195-197).
by Ian Keith Craig.
M.S.
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Celikbas, Ayse 1974. "Economics of damage controlled seismic design." Thesis, Massachusetts Institute of Technology, 1999. http://hdl.handle.net/1721.1/80487.
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Nilsson, Rebecca, and de Val Almida Winquist. "Hand Gesture Controlled Wheelchair." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-264512.
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Haptical technology is a field that is under constant development and that exists in many of today’s products, for example in VR-games and in the controls for vehicles. This kind of technology could in the same way simplify for disabled people by their being able to control a wheelchair using hand gestures. The purpose of this project is to research if a wheelchair can be controlled with hand gestures, and in that case, in which way that would be the most optimal. To answer the research questions in the project, a small scale prototype wheelchair was developed. This prototype is based on a microcontroller, Arduino, that is controlled by a sensor, IMU, that reads the angle of the user’s hand. Together, the components control two motors and steer the wheelchair. The result shows how hand gestures can steer the wheelchair forward, backward, left and right under constant speed, as well as making it stop. The prototype is able to follow the movements of the user’s hand, but reacts more slowly than would be desirable in a real situation. In spite of the fact that there are many different aspects to haptical steering of a wheelchair, this project shows that there is a large potential in implementing this kind of technology in an actual wheelchair.Haptiskt styrning är en teknologi som utvecklas snabbt och inkorporeras i många av dagens produkter, till exempel i allt från VR-spel till styrning av fordon. På samma sätt skulle denna teknologi kunna underlätta för rörelsehindrade genom att erbjuda styrning av rullstol med hjälp av handrörelser. Syftet med detta projekt var därför att undersöka om en rullstol kan styras med handrörelser och i så fall vilket sätt som är optimalt. För att besvara rapportens frågeställning har framtagningen av en prototyp av en rullstol i liten skala gjorts. Denna är baserad på en mikrodator, Arduino, som styrs av en sensor, IMU, som mäter vinkeln på användarens hand. Med hjälp av dessa kan motorerna styras och rullstolen manövreras. Resultatet av rapporten har lett till ett förslag på hur handrörelser kan styra rullstolen framåt, bakåt, till vänster och till höger under konstant fart samt få den att stanna. Protypen följer gesterna som användarens hand visar, men reagerar långsammare än vad som vore önskvärt i verkligheten. Trots att många utvecklingsmöjligheter kvarstår för haptisk styrning av en rullstol, visar detta arbete att det finns stor potential i att implementera denna teknik med handrörelsestyrning i en verklig rullstol.
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Metered, Hassan Ahmed Ahmed mohamed. "Modelling and control of magnetorheological dampers for vehicle suspension systems." Thesis, University of Manchester, 2010. https://www.research.manchester.ac.uk/portal/en/theses/modelling-and-control-of-magnetorheological-dampers-for-vehicle-suspension-systems(27de95f4-e8c2-4ce9-80d4-ba4f34848c2e).html.
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Magnetorheological (MR) dampers are adaptive devices whose properties can be adjusted through the application of a controlled voltage signal. A semi-active suspension system incorporating MR dampers combines the advantages of both active and passive suspensions. For this reason, there has been a continuous effort to develop control algorithms for MR-damped vehicle suspension systems to meet the requirements of the automotive industry. The overall aims of this thesis are twofold: (i) The investigation of non-parametric techniques for the identification of the nonlinear dynamics of an MR damper. (ii) The implementation of these techniques in the investigation of MR damper control of a vehicle suspension system that makes minimal use of sensors, thereby reducing the implementation cost and increasing system reliability. The novel contributions of this thesis can be listed as follows: 1- Nonparametric identification modelling of an MR damper using Chebyshev polynomials to identify the damping force from both simulated and experimental data. 2- The neural network identification of both the direct and inverse dynamics of an MR damper through an experimental procedure. 3- The experimental evaluation of a neural network MR damper controller relative to previously proposed controllers. 4- The application of the neural-based damper controller trained through experimental data to a semi-active vehicle suspension system. 5- The development and evaluation of an improved control strategy for a semi-active car seat suspension system using an MR damper. Simulated and experimental validation data tests show that Chebyshev polynomials can be used to identify the damper force as an approximate function of the displacement, velocity and input voltage. Feed-forward and recurrent neural networks are used to model both the direct and inverse dynamics of MR dampers. It is shown that these neural networks are superior to Chebyshev polynomials and can reliably represent both the direct and inverse dynamic behaviours of MR dampers. The neural network models are shown to be reasonably robust against significant temperature variation. Experimental tests show that an MR damper controller based a recurrent neural network (RNN) model of its inverse dynamics is superior to conventional controllers in achieving a desired damping force, apart from being more cost-effective. This is confirmed by introducing such a controller into a semi-active suspension, in conjunction with an overall system controller based on the sliding mode control algorithm. Control performance criteria are evaluated in the time and frequency domains in order to quantify the suspension effectiveness under bump and random road excitations. A study using the modified Bouc-Wen model for the MR damper, and another study using an actual damper fitted in a hardware-in-the-loop- simulation (HILS), both show that the inverse RNN damper controller potentially gives significantly superior ride comfort and vehicle stability. It is also shown that a similar control strategy is highly effective when used for a semi-active car seat suspension system incorporating an MR damper.
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Martin, Richard N. A. "Structural and mutational analysis of the controller protein C.Esp1396I and its role in gene regulation." Thesis, University of Portsmouth, 2014. https://researchportal.port.ac.uk/portal/en/theses/structural-and-mutational-analysis-of-the-controller-protein-cesp1396i-and-its-role-in-gene-regulation(6d9d7c05-bcd3-4a92-b277-a0f96444ea48).html.
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Bacterial restriction-modification (RM) systems act as a form of primitive immune system that aims to prevent foreign DNA from establishing itself within a bacterium. RM systems often function with two complementary activities; DNA methylation to label “self” DNA and DNA cleavage of unlabelled, “non-self” DNA. These two enzymatic activities require strict temporal control to prevent over-methylation or auto-restriction; the endonuclease induced degradation of genomic DNA. In some RM systems a third, controller (C) protein is employed to act as a transcription factor to control the expression of the two enzymes. Previous study, using the Esp1396I RM system as a model, has revealed how the C-protein binds to its DNA operator sequences. Unlike most C-proteins, C.Esp1396I has three binding sites; OM controls the expression of the methyltransferase and OL & OR control the expression of the C-protein and endonuclease genes as a double binding site. The binding affinities for the three sites vary by more than two orders of magnitude despite the small difference in DNA sequence. Crystallographic analysis of C.Esp1396I both as a free protein and bound to its various DNA operator sites has revealed the roles of several highly conserved residues, many of which interact with the DNA. In this study, several of these DNA binding residues were mutated in an attempt to elucidate their individual roles in the context of protein-DNA complex formation. Mutations made to those residues that interact with the phosphate backbone had a lesser effect on the binding affinity compared to those made to residues that bind to the DNA bases. Crystallographic analysis of the mutant C.Esp1396I proteins showed that the mutations had not affected the overall structure of the protein. However, what was revealed were further details of C.Esp1396I in its free state, especially the high degree of flexibility in a loop region that is key to DNA binding. During the course of this study, wild type C.Esp1396I was co-crystallised with two different DNA duplexes containing part or all of the OR site. Since there were no biologically relevant interactions in the co-crystal structures with the OR operator sequence, this gave the opportunity to observe the structure of the DNA in the un-bound state. The structure of the complex with a longer DNA fragment showed that the major groove at the OR site is opened up and prepared for C-protein binding when OL is occupied, reducing the binding penalty for this intrinsically weak operator site.
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Majhi, Somanath. "Relay feedback process identification and controller design." Thesis, University of Sussex, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297557.
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The aim of this thesis is to investigate relay feedback process identification and some controller design methods. Using an exact analysis method, namely the state space method, a set of conditions for the prediction of oscillations in relay control systems has been developed. Since the exact solution for the limit cycle is found it becomes possible to assess the stability of these oscillations using an eigenvalue criterion. A correction factor has been introduced to overcome the limitations of the Balasubramanian's eigenvalue criterion. Relay feedback identification in process control can lead to erroneous results if the system parameters are estimated from the approximate describing function approach. Exact analytical expressions are derived and on the basis of these expressions an identification procedure is suggested which is capable of estimating the parameters of a class of process transfer functions. Analytical expressions are presented for quantifying the approximate estimation errors in the presence of measurement noise and load disturbance. The performance limitations of the conventional PID controller have been clearly shown in the context of controlling resonant, unstable or integrating processes. It has been shown that a PI-PD controller with the PD in the inner loop not only avoids the derivative kick but also a better performance is achieved than with a P or D controller in the inner loop. Further, the same controller provides good disturbance rejection and its performance is often near to that of an optimum controller for disturbance rejection and is significantly better than the results of other design methods based on setpoint response. Simple tuning methods based on standard forms for a PI-PD controller controlling time delay processes have been presented which are particularly effective for integrating and unstable plants. Automatic tuning formulae for PI, PID and PI-PD controllers have been proposed for controlling stable and unstable processes. The problem of controlling integrating and unstable processes incorporating time delay has been tackled by proposing a new Smith predictor. It is shown that the predictor is capable of successfully controlling stable, integrating and unstable processes. Controller parameters leading to robust performance for various levels of uncertainty in the model parameters particularly in the unstable time constant and time delay have been presented. Also, simple and effective automatic tuning formulae are derived for the new Smith predictor structure when the plant model is not available assuming first order model with time delay for stable, unstable and integrating processes. The plant model blocks in the control structure, as well as all the controllers, are designed from a single symmetrical relay test.
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Arelhi, Roselina. "Aspects of advanced controller design and implementation." Thesis, University of Strathclyde, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366807.
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Jain, Jitendra Kumar. "Stability Analysis and Robust Controller Design of Indirect Vector Controlled Induction Motor." Thesis, 2017. http://ethesis.nitrkl.ac.in/9376/1/2017_PhD_JKJain_512EE1010.pdf.
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The thesis considers stability analysis and controller design through different performance measures for indirect vector controlled induction motor (IVCIM).These problems are known to be complex due to nonlinearity, large order and multi-loop scenario. Some new approaches and results on IVCIM are proposed in this work.
IVCIM dynamics is well known for having different bifurcation behavior, viz., saddle-node, Hopf, Bogdanov–Takens and Zero–Hopf bifurcations due to rotor resistance variation. These bifurcations affect the control performance and may lead to stalling or permanent damage of motor. A numerical analysis of these bifurcations for proportional integral (PI) controlled IVCIM is made in this thesis using full-order induction motor model (stator dynamics is included). This analysis aids to determine the allowable bifurcation parameter variation range as well as suitable choice of speed-loop gains to avoid these. Some new observations on the bifurcation behavior are made. Simulation and experimental results are presented validating the bifurcation behaviors.
For improving dynamic performance in the presence of load torque and rotor resistance variation, a new method for designing PI gains is proposed for IVCIM. The inner-loop current PI controllers are tuned simultaneously along with the speed controller. This method is implemented using a static output feedback scheme in which iterative linear matrix inequality (ILMI) based𝐻∞control technique is employed. Such a design makes stator currents and speed response to be robust against rotor resistance and load variations. A comparison between proposed design and a conventional one is shown using simulation and experimental results that validate the superiority of the proposed approach.
Owing to multi-loop and nonlinear system behavior, IVCIM dynamics is known to have coupling in between the two inner-loop stator current components (flux and torque). Such coupling affects the dynamic torque output of the motor. Decoupling of the stator currents are important for smoother torque response of IVCIM. Conventionally, additional feedforward decoupler is used to take care of the coupling that requires exact knowledge of the motor parameters and additional circuitry or signal processing. A method is proposed to design the regulating PI gains while minimizing coupling without any requirement of additional decoupler. The variation of the coupling terms for change in load torque is considered as the performance measure. The same ILMI based𝐻∞control design approach is used to obtain the controller gains. A comparison between the conventional feedforward decoupling and proposed decoupling scheme is presented through simulation and experimental results that establish the effectiveness of the proposed method riding over its simplicity.
Finally, since the PI controller can yield limited performance, a dynamic controller is designed for the IVCIM drive system. In the design process, iron-loss dynamics are incorporated into induction motor model to fetch benefit through better performance. A sequential design method is used for the controller design in which, first, the inner-loop controllers are designed. The designed inner-loop controllers is then used for designing the outer speed-loop controller. The proposed design employs ILMI based𝐻∞control design for dynamic output feedback controller that makes stator currents and speed response to be robust against disturbances. A comparison among proposed dynamic controller design, PI controller and compensator design is shown using simulation and experimental results demonstrate enhanced performance of the proposed controller and suitability for industrial purpose.
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Chang, Nai-Yun, and 張乃云. "Design and Implementation of DSP-based Speech Recognition Controller for Voice-controlled Electric Wheelchair." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/05520667294217545675.
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碩士國立成功大學
電機工程學系
88
Many people with multiple impairments need to use a powered wheelchair, voice output communication aid, environmental control, and access information technology. This thesis offers a concept of assistive technology device integration, based on a voice processor chip and a digital signal processor chip to fully integrated a speech recognition controller. The voice-controlled electric wheelchair combines a speech recognition controller with a general electric wheelchair. Using mode selector can make joystick commands and voice commands work together in the same system. Experimental results demonstrate that voice-controlled electric wheelchair can correctly execute voice commands in normal operation.
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Jheng, An-Tai, and 鄭安泰. "Implementation of Twin Sliding Mode Controllers for Sensorless Vector Controlled Induction Motor Drive with ANN Estimator." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/k8c7a6.
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碩士國立臺北科技大學
電機工程系所
93
Based on the sliding-mode control theory, this thesis studies the Twin Sliding Mode Controller (TSMC) design for the sensorless vector-controlled induction motor system. By taking the advantages of TSMC, the dynamic speed response is improved, the sensitivity of the system to disturbances is decreased, and the robustness is increased. Moreover, based on Projection Algorithm, the neural network rotor and speed estimator is proposed, which is combined with the Adaptive Pseudo-Reduced-Order Flux Observer, for the vector-controlled system to adjust the parameter according to the variations of IM. Furthermore, the speed estimator is designed using the Lyapunov approach and the projection algorithm to increase the robustness of the system and attain the control objectives of sensorless vector-controlled induction motor drive. To achieve the aim of power saving, this thesis proposes a high power efficiency control, which can reduce the flux current in steady state due to the d-q axis current ratio, to provide stable operation with high efficiency. In the testing condition that the speed range from 36 to 2000 rpm, the rotor and stator resistances are increased by 30% for the flux estimator to examine the robustness of TSMC. The experimental results show that the use of TSMC not only improves dynamic response but also has a good robustness property.
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Chen, Yi-shiuan, and 陳繹亘. "The Fabrication of an Electronic-Controlled Six-Degree-of-Freedom Flapping-Wing Platform: Motor’s Controller and Simulation." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/25894554106374753261.
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碩士國立成功大學
航空太空工程學系碩博士班
96
The electrically controlled six-degree-of-freedom ornithopter is a platform developed to imitate flapping motions of a bird's wing. A bird's wing is like a human's arm with each wing having two joints and each joint having three degrees of freedom. Therefore, a bird’s wing has six degrees of motion, which requires a total of six motors to complete the imitation. To faithfully follow the path of a flapping wing, the six motors have to be controlled synchronously. This thesis aims to design a motor control system, which drives the ornithopter platform to track the velocity command generated from the flapping motion of a bird’s wing. The control system is composed of a FPGA chip responsible for motor’s forward and backward motion control, digital tachometers to feedback the motor’s speed, D/A converters, and a wireless transmission system. The motor characteristics are identified first in the thesis and then used in the Matlab/Simulink environment to simulate the motion of the ornithopter mechanism driven by the proposed control system. Hardware testing is also conducted to validate the performance of the control system and to compare with the simulation results.
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Ribeiro, Simão Pedro Rocha. "Smart Hydraulics Controller." Dissertação, 2014. https://repositorio-aberto.up.pt/handle/10216/101443.
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Hwang, Yeou Yuan, and 黃友元. "A Study of Self-Organized Fuzzy Controller to Improve PID-Controller and Robust-Controller." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/61566220784745251989.
Full textAbstract:
碩士國立成功大學
造船及船舶機械工程學系
87
The performance of fuzzy logic controller can be improved though the following methods: the structure of controller , the tuning of parameters and the regulating of control rules。 The last one is the most effective among them。Rules self-regulating fuzzy controller is one of those being able to modify fuzzy automatically。Now we prefer a algorithm to realize the technique of self-organized fuzzy controller to adjust change of error gain。It can control close loop system freely arrive steady state time。The self-organized fuzzy controller is assist controller to improve the performance of a master PID-controller and Η∞ controller and result of computer simulation show that the complex controller(Fuzzy-Η∞ controller or Fuzzy-PID controller) is better than the original PID controller and PID controller no matter in the reduction of rise time , overshoot , or settling time 。