Engineering Commons^™

Dynamic Modeling Of Human Gait And Motor, Chad Everett Joshua Macdonald

Open Access Theses & Dissertations

The simulation of gait, impairments and the outcomes of rehabilitation strategies is an important area of research. The ability to study the efficacy of treatment options before applying them to patients has the potential to improve the efficiency of the rehabilitation process. Any such simulations must incorporate some model of the motor learning process to properly anticipate the responses of patients.This dissertation presents initial work on the modeling of gait and the study of motor adaptation with a view towards simulating the motor adaptation process during gait.

Specifically, an inverse dynamic model of gait incorporating sagittal plane limb and torso …

Novel Control Technique For Cadmium Sulfide, Rafael Ordonez

Open Access Theses & Dissertations

Cadmium sulfide Chemical-Bath-Deposition parameters are modified to allow, for the first time, real time monitoring of cadmium ion molarity using a commercially available cadmium ion Ion-Selective-Electreode at 60°C. This modification involves alterations to typical deposition parameters that eliminate the formation of cadmium hydroxide and keep cadmium ion molarity above 10-7M. The new or atypical parameters developed are pH values below 8.9 and lower moralities for all chemicals. In order to have complexation of cadmium ion driven mainly by ammonia, parameters that minimized complexation by other chemicals are found. Cadmium acetate concentration below 2mM and ammonium acetate concentration below 10mM minimize …

Resistive Switching Of Tin Dioxide (Sno2) For Memristor Applications, Sergio Fabian Almeida

Open Access Theses & Dissertations

In the last decades new electrical devices have been investigated in order to overcome problems caused by integrated circuit shrinking. Within these devices there is one that has attracted much attention due to its high scalability and simple structure. This device was proposed theoretically by Leon Chua in 1971 who gave it the name of "Memristor". In the recent years thin films structures composed of a metal/oxide/metal (MOM) stack have been linked to this new device, also known as "Resistive switching". There are several applications for the memristor; one of the most important is for resistive random access memory (ReRAM) …

Slow Complexity Wavelet Packet Compression Of Bayer Images For Communication Over Wireless Sensor Networks, Ivan Calzada

Open Access Theses & Dissertations

The purpose of this thesis was to develop a low complexity image compression algorithm for Wireless Sensor Networks (WSN). The main constraints in a WSN node are limited processing power, memory allocation, and battery life. The goal of this thesis was to develop an image compression algorithm that would thrive under this constraint environment. The main focus was to minimize the complexity of the algorithm by taking advantage of the spatial correlation found in Bayer images. The algorithm employs line based 1-D Discrete Wavelet Packets Transform of Bayer images. In addition the image compression method includes the application of a …

Simulation And Optimization Of Ultra Thin Photovoltaics, Jose Luis Cruz-Campa

Open Access Theses & Dissertations

Sandia National Laboratories (SNL) conducts pioneering research and development in Micro-Electro-Mechanical Systems (MEMS) and solar cell research. This dissertation project combines these two areas to create ultra-thin small-form-factor crystalline silicon (c-Si) solar cells. These miniature solar cells create a new class of photovoltaics with potentially novel applications and benefits such as dramatic reductions in cost, weight and material usage.

At the beginning of the project, unusually low efficiencies were obtained in the research group. The intention of this research was thus to investigate the main causes of the low efficiencies through simulation, design, fabrication, and characterization.

Commercial simulation tools were …

Computer-Aided Detection Of Sleep Apnea And Sleep Stage Classification Using Hrv And Eeg Signals, Edson F. Estrada

Open Access Theses & Dissertations

Sleep is a circadian rhythm essential for human life. Many events occur in the body during this state. In the past, significant efforts have been made to provide clinicians with reliable and less intrusive tools to automatically classify the sleep stages and detect apnea events. A few systems are available in the market to accomplish this task. However, sleep specialists may not have full confidence and trust in such systems due to issues related to their accuracy, sensitivity and specificity. The main objective of this work is to explore possible relationships among sleep stages and apneic events and improve on …

Design And Simulation Of A Position Sensitive Device With Gaussian Response, Debra Erin Medina

Open Access Theses & Dissertations

Not Required

Compressive Sensing With Prior Information Applied To Magnetic Resonance Imaging, Cristiano Jacques Miosso

Open Access Theses & Dissertations

This dissertation introduces the theory of compressive sensing with prior information about a signal's sparse representation. We show, mathematically and in numerical simulations, that prior information improves signal reconstruction, in terms of number of required measurements, computation time and signal-to-noise ratios. Following, we present a set of methods for enhanced magnetic resonance imaging and tomography that can be combined with prior information, for enhanced image quality.

In developing the theory of compressive sensing with prior information, we provide a mathematical proof of the required condition (in terms of number of linear measurements) for reconstruction using the ideal approach of l0-minimization, …

Generation Of High Resolution Radar Signals Using Three Dimensional Chaotic Flows, Chandra Sekhar Pappu

Open Access Theses & Dissertations

The purpose of this project is to investigate the system parameter and certain signal processing techniques to achieve wide bandwidth and frequency agility in order to build a high resolution radar. The technique relies on the output of an n-dimensional (n>2) non-linear system that exhibits chaotic behavior.

Firstly, the compressed Lorenz attractor is considered which has a set of three state variables x, y and z and three control parameters &rho, &beta, and &sigma. By varying &rho and &beta as function of time highly chaotic parameter space region is simulated such that chaotic signal behaves optimally.

For comparison purpose …

Investigation Of Selective Nanohetero-Epitaxy Growth On Si(100) Substrates For Hgcdte Infrared Detector Applications, Aryzbe Diaz

Open Access Theses & Dissertations

The selective CdTe Nanohetero-Epitaxy growth on Si(100) substrates has been achieved without the use of a mask in an attempt to reduce the dislocation density at the CdTe/Si interface to 10⁵/cm³ using the Close-Space Sublimation (CSS) technique, which is a low-cost effective technique for the deposition of polycrystalline CdTe films. Furthermore, CdTe is a compound semiconductor with a direct bandgap of 1.5 eV, which makes it an ideal material for the applications of infrared detectors and solar cells. It has been demonstrated that the selective growth of CdTe on patterned Si(100) substrates results in CdTe grains with …

Sensor Interpolation And Super Resolution Image Reconstruction Using The Optimal Recovery Framework, Veenarai Moram

Open Access Theses & Dissertations

Wireless sensor networks have the potential to benefit society in a myriad of ways, but due to constraints of sensor placement, obtaining the desired signals is not an easy problem. Retrieving the information accurately from sensors placed randomly is a challenging problem of sensor communication and signal interpolation. In this research the optimal recovery (OR) method, a deterministic framework that can use a priori bandwidth or spectral shape information, is used to interpolate from the given samples produced by sensors. In the reconstruction formulation, a worst case error signal occurs. To minimize this error, the OR method uses a norm …

12 Bit Charge Redistribution Digital To Analog Converter For The Residence Time Fluxgate Magnetometer, Miguel Angel Alamillo

Open Access Theses & Dissertations

The continuous advances in CMOS VLSI technology have culminated in high speed, low voltage CMOS digital circuits with gate delays below 50 ps at 1.5 V supply. At the same time, high voltage analog signal processing has fallen behind to the high flexibility and high reliability of DSP. However, the main drawback of DSP is the need for high accuracy low distortion data converters and as a consequence of the persistent efforts of reducing size, cost and power of solid-state components the field of CMOS Mixed-Signal circuit design has become of the utmost importance.

The obvious functionality of data converters …

Novel Control Technique For Cadmium Sulfide Chemical Bath Deposition Using Real Time Monitoring Of Cadmium Ion Molarity, Rafael Ordonez

Open Access Theses & Dissertations

Cadmium sulfide Chemical-Bath-Deposition parameters are modified to allow, for the first time, real time monitoring of cadmium ion molarity using a commercially available cadmium ion Ion-Selective-Electreode at 60°C. This modification involves alterations to typical deposition parameters that eliminate the formation of cadmium hydroxide and keep cadmium ion molarity above 10-7M. The new or atypical parameters developed are pH values below 8.9 and lower moralities for all chemicals. In order to have complexation of cadmium ion driven mainly by ammonia, parameters that minimized complexation by other chemicals are found. Cadmium acetate concentration below 2mM and ammonium acetate concentration below 10mM minimize …

Using Bayesian Inference In Design Applications, Chung Yong Chan

Electronic Theses and Dissertations

This dissertation presents a new approach for solving engineering design problems such as the design of antenna arrays and finite impulse response (FIR) filters. In this approach, a design problem is cast as an inverse problem. The tools and methods previously developed for Bayesian inference are adapted and utilized to solve design problems. Given a desired design output, Bayesian parameter estimation and model comparison are employed to produce designs that meet the prescribed design specifications and requirements. In the Bayesian inference framework, the solution to a design problem is the posterior distribution, which is proportional to the product of the …

Protection Of Upqc Against The Load Side Short Circuits, Iurie Axente, Malabika Basu, Michael Conlon, Kevin Gaughan

Articles

This study presents a protection scheme for protecting the series inverter of a unified power quality conditioner (UPQC). The proposed scheme protects the series inverter from overcurrents and overvoltages, which appear during short-circuit faults on the load side of the UPQC. The main protection element is a crowbar connected across the secondary of the series transformer and consists of a pair of antiparallel connected thyristors, which is governed by a simple Zener diode-based control circuit. In the case of an overvoltage, the crowbar short circuits the secondary of the transformer, thus removing the overvoltage and diverting the fault current from …

The Design And Manufacture Of A Light Emitting Diode Package For General Lighting, Michael S. Krist

Master's Theses

Lighting technologies have evolved over the years to become higher quality, more efficient sources of light. LEDs are poised to become the market standard for general lighting because they are the most power efficient form of lighting and do not contain hazardous materials. Unfortunately, LEDs pose unique problems because advanced thermal management is required to remove the high heat fluxes generated by such relatively small devices. These problems have already been overcome with complex packaging and exotic materials, but high costs are preventing this technology from displacing current lighting technologies.

The purpose of this study is to develop a low-cost …

Passive All-Fiber Wavelength Measurement Systems: Performance Determination Factors, Ginu Rajan, Yuliya Semenova, Agus Hatta, Gerald Farrell

Books/Book Chapters

No abstract provided.

Wireless Sensor Network Radio Power Management And Simulation Models, Michael I. Brownfield, Theresa Nelson, Scott Midkiff, Nathaniel J. Davis Iv

Faculty Publications

Wireless sensor networks (WSNs) create a new frontier in collecting and processing data from remote locations. The IEEE 802.15.4 wireless personal area network-low rate (WPAN-LR) WSNs rely on hardware simplicity to make sensor field deployments both affordable and long-lasting without maintenance support. WSN designers strive to extend network lifetimes while meeting application-specific throughput and latency requirements. Effective power management places sensor nodes (or motes) into one of the available energy-saving modes based upon the sleep period duration and the current state of the radio. The newest generation of WPAN-LR-based sensor platform radios operates at a 250 kbps data rate and …

Psuedo-Randomly Controlled Analog Synthesizer, Jared Huntington

Electrical Engineering

The goal of this project was to design and build a portable box recreating classic sounds heard in science fiction films. These include sounds ranging from droning hums to bloops and bleeps. Currently no other device is made specifically for generating these sounds. The user controls and manipulates the sounds produced using a combination of switches and knobs to shape the sound generation. The sounds are generated using analog electronics. The project was successful in meeting the desired goal by designing and building a Randomizer, MIDI controller, VCO, LFO, VCA, Ring Modulator, and Fuzz Section. The resulting device is useful …

Switching Circuit For A Permanent Magnet Dc Motor, Alex Boatman

Electrical Engineering

The project is a circuit that will basically supply current from the battery to the different stator coils at opportune moments. With a hall-effect sensor on the shaft as a feedback to a microcontroller, I was able to toggle switches based on the position of the shaft at the moments where we would be using as little power as possible. The operation of the control circuit works similar to a stepper motor; it takes a signal from the microcontroller that is sent to some FET drivers, which in turn sends signals to the FETs to open or close as the …

Automated Basketball Return System, Victor Mendoza, Chris Chamberlain

Electrical Engineering

The project is meant to assist a basketball player in their practicing. The project hangs directly on the basketball rim and automatically rotates to find the player on the court. Once the player is detected, the automated basketball return system (ABRS) stays focused in the direction of the player so that any baskets successfully made will be funneled back to the player. When the player moves from center, IR motion detectors find which direction you moved to and rotates accordingly, until the player is focused in front of the funnel again. If at any time the player is absent from …

Dc-Dc Converter For Harvesting Energy From An Exercise Bike, Henry Ureh, Chris Henry

Electrical Engineering

Create an efficient buck-boost converter that adapts to input voltage range from ~3.8V to 70V, and outputs 13.7V DC, the voltage required by a charge controller to charge a battery. The energy stored in the battery will be supplied back to the grid.

The cost of energy saved by the converter should eventually cover the initial price of the converter. The converter should help reduce the net power consumption of the exercise machines used in the Cal Poly gym

High Contrast Grayscale Object Tracking Embedded System Design, Scott Donald Neally

Electrical Engineering

The purpose of this project is to prove that a real-time object-tracking camera can be implemented using the Digilent NEXYS board with Xilinx Platform Studio. With great ambition I set to implement the camera with RGB color tracking of bright green objects. This would make segmentation between the object of interest and its background much easier, allowing less stringent requirements on the background color beyond the object. Because of time restraints, the actual implementation remains as 8-bit grayscale, where the object of interest is intended to be white and highly contrasted from its black background. A simple algorithm is used …

Musicman Communications System, Dan Strengier

Electrical Engineering

The MusicMan portable music mixer is a solution for users who enjoy listening to music and would also like to communicate to friends on a walkie-talkie system. The MusicMan provides the user the ability to simultaneously listen to an MP3 player and operate a communications device, such as a walkie-talkie.

Punching Bag Trainer, Gian Delacruz

Electrical Engineering

Martial artists, such as boxers, kick boxers, and karate practitioners, use punching bags in training all the time to work on technique, speed and power but there hasn’t really been a good way to train reaction and combination speed (a combination is a string of strikes) without the aid of a training partner. Reaction and combination speed are important in competition because a faster competitor can attack successfully before his or her opponent has the time to react. This device aims to help martial artists increase reaction and combination speed through the use of randomly flashing targets attached to a …

Protected Ir Input System, Kevin Ersoy

Electrical Engineering

The result of this project is a product that may be used to apply a digital input to a system without physically touching a device. The combination of a modulated IR signal and reflective technology produces this remote actuation. The signal emitter should produce the modulated IR light, and the receiver should continuously wait for this signal to be received. If the IR signal should encounter an obstruction causing reflection at the appropriate distance, it will be reflected directly into the receiving device. This project may be extended to include multiple duplicate systems in proximity by transmitting a modulated digital …

Wireless Pedometer, Jeffrey Lease

Electrical Engineering

No abstract provided.

Automatic People Counting And Matching, John Sallay

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis explores software algorithm for implementing a people counting and matching system to be used on a bus. A special camera is used, known as a texel camera, that generates depth and color information for a scene. This added information greatly facilitates both the tasks of matching and counting.

Although people counting is a relatively mature field, there are several situations in which current technologies are not able to count correctly. Several of these difficult situations are tested with 82% counting accuracy.

The idea of matching people on a bus is also developed. The goal is not to identify …

Methodology To Derive Resource Aware Context Adaptable Architectures For Field Programmable Gate Arrays, Harikrishna Samala

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The design of a common architecture that can support multiple data-flow patterns (or contexts) embedded in complex control flow structures, in applications like multimedia processing, is particularly challenging when the target platform is a Field Programmable Gate Array (FPGA) with a heterogeneous mixture of device primitives. This thesis presents scheduling and mapping algorithms that use a novel area cost metric to generate resource aware context adaptable architectures. Results of a rigorous analysis of the methodology on multiple test cases are presented. Results are compared against published techniques and show an area savings and execution time savings of 46% each.

Swept-Frequency Sampled Grating Distributed Bragg Reflector Lasers Optimized For Optical Coherence Tomography Applications, Brandon J. George

Master's Theses

Swept Frequency Source Optical Coherence Tomography (OCT) requires high repetition rate and wide spectral width wavelength tunable sources at a low cost. The sampled grating distributed Bragg reflector (SG-DBR) laser provides wide wavelength tuning range while exhibiting a wavelength switching speed that is among the fastest currently available. The SG-DBR laser is used to generate linear frequency ramps with high repetition rates. Since the SG-DBR laser is currently used for the telecommunications industry in high volume, the price of the system is much lower than current OCT sources. Therefore the SG-DBR laser provides a practical solution for Swept Source OCT. …