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Modellering, identifiering och reglering av skannern i ett laserbatymetrisystem / Modeling, identification and control of the scanner in a system for laser bathymetryJaneke, Hanna January 2005 (has links)
<p>The purpose with this masters thesis was to model the scanner in a system for laser bathymetry. The model was then used to develop a controller for the scanner so a good search pattern was achieved. </p><p>Two different types of models have been tested, a physical model and a Black Box model of Box Jenkins type. The physical model has been derived from Lagranges equations. Identification experiments have been used to compute the Black Box model and to find the unknown parameters in the physical model. </p><p>Three different controllers have been tested, a PID controller, a model predictive controller and a controller with feedforward. The controller with feedforward gave the best result. By softening the reference signal and using feedforward a good search pattern was achieved.</p>
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Modellering, identifiering och reglering av skannern i ett laserbatymetrisystem / Modeling, identification and control of the scanner in a system for laser bathymetryJaneke, Hanna January 2005 (has links)
The purpose with this masters thesis was to model the scanner in a system for laser bathymetry. The model was then used to develop a controller for the scanner so a good search pattern was achieved. Two different types of models have been tested, a physical model and a Black Box model of Box Jenkins type. The physical model has been derived from Lagranges equations. Identification experiments have been used to compute the Black Box model and to find the unknown parameters in the physical model. Three different controllers have been tested, a PID controller, a model predictive controller and a controller with feedforward. The controller with feedforward gave the best result. By softening the reference signal and using feedforward a good search pattern was achieved.
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Reconfigurable equalization for 10-Gb/sec serial data links in a 0.18-μm CMOS technologyBien, Franklin Young-Jae 13 November 2006 (has links)
The objective of the proposed research is to realize a 10-Gb/sec serial data link over band-limited channels, such as backplanes, multi-mode fiber, and copper-based cables that were originally designed for data rates less than 1Gb/sec. This is achieved using electrical equalization implemented in an integrated circuit (IC). To successfully compensate for various band-limited channels at the targeted data rate with a single equalizer IC, a reconfigurable equalizer topology is proposed.
In order to realize the proposed goal, various channels are characterized of their forward transmission frequency response. Based on the measured channel data, system simulations are performed to identify the required specifications for IC implementation. This provides information such as optimal number of taps, fractionally-spaced tap delay, and tap coefficients for the proposed IC. With the obtained system requirements, IC building blocks are designed and fabricated in a 0.18- and #956;m CMOS technology.
The fully-integrated reconfigurable CMOS equalizer provides a single-chip solution for compensating various band-limited channels. This enables 10-Gb/sec serial data transmission achieving signal integrity beyond their designed specifications.
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The Bias Circuit Design of High Gain High Frequency OTALuo, Chi-Chuan 07 August 2008 (has links)
In this thesis, we use the no-capacitor feed-forward (NCFF) compensation scheme which employs a feed-forward path to obtain high gain, high frequency. We use CMFB circuit to adjust the common-mode output voltages and the bias circuit. The CMFB circuit makes the output accurately to the reference voltage.
The circuit was designed and fabricated TSMC 0.35 £gm CMOS process. The dc gain is around 90dB and the cut-off frequency is 1GHz. The supply voltage is ¡Ó1.25V. The output voltage is smaller than 10mV.
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Teaching Social Skills to Children with Asperger’s and High Functioning Autism: An Evaluation of Video Self-Modeling and Behavior Skills TrainingMcFee, Krystal M. 01 July 2010 (has links)
The purpose of this study was to evaluate the effects of video self-modeling and
behavior skills training to teach social skills to children with Asperger’s and high
functioning autism. The targeted social skills were social initiations and social responses.
The video self-modeling alone condition was implemented first using a video
feedforward approach. A behavior skills training (BST) procedure was implemented
following the video self-modeling alone condition for each participant. BST consisted of
instructions, modeling, rehearsal, and feedback. The frequency of each target behavior
was scored from videotapes using 10-second frequency within interval recording. After
the video self-modeling was introduced, a mean increase was demonstrated in the target
behaviors for 3 of the 4 participants. However, following the video self-modeling plus
behavior skills training procedures, the social skills increased further for each participant.
Follow up measures showed that the social interactions for each participant remained
higher than baseline, however slightly lower than levels during BST+VSM.
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Video content analysis for automated detection and tracking of humans in CCTV surveillance applicationsTawiah, Thomas Andzi-Quainoo January 2010 (has links)
The problems of achieving high detection rate with low false alarm rate for human detection and tracking in video sequence, performance scalability, and improving response time are addressed in this thesis. The underlying causes are the effect of scene complexity, human-to-human interactions, scale changes, and scene background-human interactions. A two-stage processing solution, namely, human detection, and human tracking with two novel pattern classifiers is presented. Scale independent human detection is achieved by processing in the wavelet domain using square wavelet features. These features used to characterise human silhouettes at different scales are similar to rectangular features used in [Viola 2001]. At the detection stage two detectors are combined to improve detection rate. The first detector is based on shape-outline of humans extracted from the scene using a reduced complexity outline extraction algorithm. A Shape mismatch measure is used to differentiate between the human and the background class. The second detector uses rectangular features as primitives for silhouette description in the wavelet domain. The marginal distribution of features collocated at a particular position on a candidate human (a patch of the image) is used to describe statistically the silhouette. Two similarity measures are computed between a candidate human and the model histograms of human and non human classes. The similarity measure is used to discriminate between the human and the non human class. At the tracking stage, a tracker based on joint probabilistic data association filter (JPDAF) for data association, and motion correspondence is presented. Track clustering is used to reduce hypothesis enumeration complexity. Towards improving response time with increase in frame dimension, scene complexity, and number of channels; a scalable algorithmic architecture and operating accuracy prediction technique is presented. A scheduling strategy for improving the response time and throughput by parallel processing is also presented.
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Design, Simulation and Implementation of High Precision Control Algorithms for a Galvanometer Laser ScannerTorres Bonet, Tomas 26 August 2014 (has links)
This thesis focuses on the theory, design, simulation and implementation of
several digital controllers for periodic signals on a laser scanning galvanometer. A model for the galvanometer was obtained and veri ed using closed
loop identi cation techniques. Using this model, controllers were designed
and simulated using MATLAB and then implemented on a custom FPGA
control processor with a focus on tracking performance. The types of controllers used were: an Iterative Learning Controller, an RST pole placement
controller, an Adaptive Feed-forward cancellation controller, a combined Iterative Learning and Adaptive Feed-forward cancellation controller and a
simple PID controller.
The simulated results were better than the experimental results because of
system noise and modelling uncertainties but the relative performance between each of the controllers was similar for both the simulation and experimental setup. The experimental results achieved were very good with one
controller reaching errors under 50 rad. / Graduate / 0537 / t_Torres_bonet@hotmail.com
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The inhibitory microcircuit in mouse presubiculum : from interneuron properties to input-output connectivity / Le microcircuit inhibiteur dans le presubiculum : propriétés des interneurons et leur connectivitéNassar, Mérie 16 September 2016 (has links)
L’orientation spatiale et la fonction de navigation sont des processus contrôlés par des circuits et éléments neuronaux bien précis. Le présubiculum, aire cortical de transition de la région parahippocampique, est situé entre l’hippocampe et le cortex entorhinal. Le présubiculum est impliqué dans la navigation spatiale à la fois chez l’animal et l’Homme. Plus de la moitié des neurones du présubiculum sont des cellules de direction de la tête qui déchargent en fonction de la direction prise par la tête de l’animal. Le présubiculum est un carrefour majeur pour le transfert d’information de direction de la tête et de l’information visuelle aux régions de la formation hippocampique et parahippocampique et sous-corticale. Malgré son importance fonctionnelle, le traitement de l’information au sein du circuit présubiculaire à 6 couches reste encore peu connu. Au cours de ma thèse, j’ai étudié les éléments inhibiteurs qui composent le microcircuit présubiculaire à partir de tranches aigües de cerveau de souris en utilisant la technique du patch-clamp. J’ai caractérisé les propriétés anatomique et électriques des interneurones ainsi que leur connectivité locale et à distances avec d’autres régions corticales.Dans un premier temps, j’ai étudié la diversité des interneurones exprimant la parvalbumine et la somatostatine à partir de lignées de souris transgéniques exprimant une protéine fluorescente dans les interneurones. J’ai montré l’existence des cellules en panier à décharge rapide exprimant la parvalbumine et des cellules de Martinotti à bas seuil d’activation exprimant la somatostatine. J’ai également décrit un troisième groupe atypique avec des propriétés électriques intermédiaires et des morphologies hétérogènes. L’existence de ce groupe transitionnel pourrait s’expliquer par la présence d’interneurones exprimant à la fois la parvalbumine et la somatostatine. Ainsi, le microcircuit inhibiteur du présubiculum semble partager toute la complexité des autres aires corticales. Dans un second temps, je me suis intéressée à l’intégration des entrées thalamiques par les neurones excitateurs et inhibiteurs dans les couches superficielles du présubiculum à l’aide de la technique du double patch-clamp. J’ai montré que les axones thalamiques innervent sélectivement les couches superficielles et plus particulièrement, contactent directement les cellules de projection vers le cortex entorhinal ainsi que les interneurons exprimant la parvalbumine dans la couche 3 du présubiculum. En revanche, les interneurons exprimant la somatostatine sont indirectement recrutés par les cellules pyramidales du microcircuit. Ces interneurones joueraient un double rôle à la fois dans l’inhibition latérale et le maintien d’une décharge soutenue des cellules principales. Du fait de la forte probabilité de connexion entre les cellules principales et les interneurones exprimant la parvalbumine, ces derniers seraient impliqués dans l’inhibition de type feed-forward. Mon travail de thèse a permis d’apporter des connaissances fondamentales concernant l’inhibition au sein du présubiculum. Il a permis de dévoiler une diversité d’interneurones GABAergiques et de montrer l’existence de circuits neuronaux canoniques de type « feedforward » et « feedback » qui seraient recrutés à différents moments de la signalisation de la direction de la tête. / Spatial orientation and navigation are controlled by specific neuronal circuits and elements. The presubiculum, a transitional cortical area of the parahippocampal formation, is located between the hippocampus and the entorhinal cortex, and it participates in spatial navigation in animals and humans. More than half of presubicular neurons are head direction cells that fire as a function of the directional heading. The presubiculum is thought to be a crucial node for transferring directional heading information to the entorhinal-hippocampal network, and feeding back visual landmark information to upstream regions of the head directional circuit. Despite its functional importance, information processing within the 6-layered presubicular microcircuit remains not completely understood. During my PhD, I studied inhibitory neurons of the presubicular microcircuit in the slice preparation using patch-clamp recordings. I characterized their anatomo-physiological properties as well as their functional connectivity with local principal neurons. In the first part, I examined the diversity of two major populations of GABAergic neurons, the parvalbumin (PV) and somatostatin (SOM) expressing interneurons in mouse presubiculum. Using transgenic mouse strains Pvalb-Cre, Sst-Cre and X98, where interneurons were fluorescently labeled, I showed the existence of typical PV fast-spiking basket-like interneurons mainly in the Pvalb-Cre line and SOM low-threshold spiking Martinotti cell-like interneurons in the X98 and Sst-Cre line. Unsupervised cluster analysis based on electrophysiological parameters further revealed a transitional group containing interneurons from either Pvalb-Cre or Sst-cre lines with quasi-fast-spiking properties and heterogeneous morphologies. A small subpopulation of ~6% of interneurons co-expressed PV and SOM in mouse presubiculum. The presubiculum appears to share the whole complexity of other cortical areas in term of inhibition. In the second part, I investigated the integration of thalamic inputs by principal neurons as well as PV and SST interneurons in the presubiculum using double patch-clamp recordings. I found that thalamic axons selectively innervated superficial layers and made direct synaptic contacts with pyramidal neurons that project to medial entorhinal cortex and also with PV interneurons in superficial layer 3. In contrast, SST interneurons were indirectly recruited by presubicular pyramidal cells in a facilitating and frequency dependent manner. They may mediate lateral inhibition onto nearby principal cells, and at the same time, preserve sustained firing of principal neurons. In paired recording experiments, I found that PV cells inhibit neighboring pyramidal neurons with a high connection probability. PV interneurons are rapidly recruited by thalamic excitation and mediate feed-forward inhibition in presubicular pyramidal neurons. My PhD work brought fundamental knowledge about the presubicular inhibitory microcircuit. It has unraveled different populations of GABAergic interneurons and revealed canonical feedforward and feedback inhibitory motifs that are likely to be recruited at different times during head direction signaling.
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Design and Simulation of Boost DC - DC Pulse Width Modulator (PWM) Feed-Forward Control ConverterFranklin, Calenia L. 05 August 2020 (has links)
No description available.
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Trajectory-Tracking Control of the Ball-and-Plate SystemRiccoboni, Dominic E 01 March 2023 (has links) (PDF)
The Mechatronics group in the Mechanical Engineering department of Cal Poly is interested in creating a demonstration of a ball-and-plate trajectory tracking controller on hardware. The display piece will serve to inspire engineering students to pursue Mechatronics and control theory as an area of study. The ball-and-plate system is open-loop unstable, underactuated, and has complicated, nonlinear equations of motion. These features present substantial challenges for control - especially if the objective is trajectory tracking. Because the system is underactuated, common nonlinear trajectory tracking control techniques are ineffective. This thesis lays out a theoretical foundation for controlling the hardware.
Several important concepts related to ball-and-plate trajectory tracking control are presented. Models of the system, with various assumptions, are given and used in deriving control law candidates. To limit project scope, reasonable control criteria are introduced and used to evaluate designs from the thesis. Several control architectures are explored, these being Full-State Feedback with Integral Action, Single-Input-Single-Output Sliding Mode, and Full-State Feedback with Feed Forward. The mathematical reasoning behind each is detailed, simulation results are shown to validate their practicality and demonstrate features of the architectures, and trajectory similarity measure studies are produced to evaluate controller performance for a wide range of setpoint functions.
The Full-State Feedback with Feed Forward controller is recommended based on its theoretical advantages and compliance with the control criteria over the competing designs. The control architecture has a proof of asymptotic tracking in the linear model, has excellent performance in simulations that use a nonlinear plant model, and produces the most pleasing visual experience when viewed in animation.
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