Engineering Commons^™

A Fault Tolerant, Data Fusion System For Navigation Applications To A Ducted Fan Vtol Uav, Jian Lu

Dissertations, Master's Theses and Master's Reports

A Fault Tolerant, Data Fusion (FTDF) algorithm for a Ducted Fan Unmanned Aerial Vehicle (DFUAV) Navigation System is presented. The algorithm have two parts: Gradient Descent (GD) for the Attitude and Heading Reference System (AHRS) and an Interacting Multiple Model (IMM) for position estimation. The GD methodology was designed to fuse the gyroscope, accelerometer, and geomagnetic sensors. The IMM algorithm is able to identify and compensate for multiple sensors data failures. There are three parts in the presentation.

Firstly, system identification and the Allan Variance method is used to build dynamic models and noise models for multiple Sensors and Actuators. …

Nanosphere Lithography And Its Application In Rapid And Economic Fabrication Of Plasmonic Hydrogenated Amorphous Silicon Photovoltaic Devices, Chenlong Zhang

Dissertations, Master's Theses and Master's Reports

Solar photovoltaic (PV) devices harvest energy from solar radiation and convert it to electricity. PV technologies, as an alternative to traditional fossil fuels, use clean and renewable energy while minimizing pollution. For decades researchers have been developing thin film solar cells as an important alternatives to the relatively expensive bulk crystal solar cell technology. Among those, hydrogenated amorphous silicon (a-Si:H) solar cells prevails for good efficiency, non-toxic and materially abundant nature. However, a-Si:H thickness must be minimized to prevent light induced degradation, so optical enhancement is necessary. Light manipulation has to be applied and carefully engineered to trap light within …

Predictive Control Of Power Grid-Connected Energy Systems Based On Energy And Exergy Metrics, Meysam Razmara

Dissertations, Master's Theses and Master's Reports

Building and transportation sectors account for 41% and 27% of total energy consumption in the US, respectively. Designing smart controllers for Heating, Ventilation and Air-Conditioning (HVAC) systems and Internal Combustion Engines (ICEs) can play a key role in reducing energy consumption. Exergy or availability is based on the First and Second Laws of Thermodynamics and is a more precise metric to evaluate energy systems including HVAC and ICE systems. This dissertation centers on development of exergy models and design of model-based controllers based on exergy and energy metrics for grid-connected energy systems including HVAC and ICEs.

In this PhD dissertation, …

Design And Simulation Of A Residential Pv-Battery System, Sevket Burak Ovali

Dissertations, Master's Theses and Master's Reports

This thesis provides the design and simulation of a stand-alone photovoltaic (PV) system to ensure the load demands for a single residential in Houghton (MI) and Tucson (AZ). The fundamental activities of this study aim to model for particular stand-alone photovoltaic of components. Entire stand-alone design stages for used load data sets are carried out. Daily irradiance and load data are taken into consideration throughout the design stages. The Simulink program is developed to obtain simulation results to observe PV system and battery behaviors regarding various months which have most various irradiances throughout 30 days. Sizing of PV systems is …

Channel Modeling For Fifth Generation Cellular Networks And Wireless Sensor Networks, Amir Torabi

Dissertations, Master's Theses and Master's Reports

In view of exponential growth in data traffic demand, the wireless communications industry has aimed to increase the capacity of existing networks by 1000 times over the next 20 years. A combination of extreme cell densification, more bandwidth, and higher spectral efficiency is needed to support the data traffic requirements for fifth generation (5G) cellular communications. In this research, the potential improvements achieved by using three major 5G enabling technologies (i.e., small cells, millimeter-wave spectrum, and massive MIMO) in rural and urban environments are investigated. This work develops SPM and KA-based ray models to investigate the impact of geometrical parameters …

High Resolution Time-Of-Arrival Ranging Of Wireless Sensor Nodes In Non-Homogenous Environments, Mohsen Jamalabdollahi

Dissertations, Master's Theses and Master's Reports

Wireless Sensor Networks (WSN) have emerging applications in homogeneous environments such as free space. In addition, WSNs are finding new applications in non-homogeneous (NH) media. All referred applications entail location information of measured data or observed event. Localization in WSNs is considered as the leading remedy, which refers to the procedure of obtaining the sensor nodes relative location utilizing range measurements. Localization via Time-of-Arrival (ToA) estimation has received considerable attention because of high precision and low complexity implementation, however, the traditional techniques are not feasible in NH media due to frequency dispersion of transmitted ranging waveform.

In this work, a …

A Novel Low Latency, High Resolution And Low Cost Time Synchronization, Ali Aghdaei

Dissertations, Master's Theses and Master's Reports

This report presents a new low latency, high resolution and low cost timing synchro- nization technique for digital receivers. Traditional timing synchronization employs Matched filter to perform cross-correlation operation and estimate Time-of-Arrival (TOA) of the signal. Decreasing the latency of the traditional method through over- sampling leads to a higher complexity and it is not viable. Furthermore, to obtain a high-resolution TOA, an extensive bandwidth is required, which results in high system complexity. The proposed method uses single bit quantization to employ XNOR blocks instead of multiplier and accumulator (MAC) blocks in the traditional method. This substantially decreases complexity incorporating …

Small Size Coupling Feed And Inductive Shorting Antenna For Wide Bandwidth, Increased Gain And Efficiency With Low Specific Absorption Rate (Sar) Operation, Md Mahfuzur Rahman

Dissertations, Master's Theses and Master's Reports

Day by day technology is changing our lives rapidly. With these radical changes, demands in communication industry are also increasing drastically. To cope up with these demands, 2G, 3G, 4G, LTE (Long Term Evolution) communication systems have been introduced. Modern cellular phone should be capable to operate in wide range of frequency spectrum for their global access to provide end user customers these communication services. Hence mobile antennas should be designed in such a way that they should generate wideband operation. But commercially available standalone mobile antennas aren’t capable to operate in all those communication systems, several antennas are used …

Analysis On The Performance Limitations Of An Interferometric Geolocation Device, Michael Witt

Dissertations, Master's Theses and Master's Reports

GPS is a critical tool often used in terrestrial location and navigation. However, GPS relies on a system of satellites in medium earth orbit and is prone to dropouts at higher latitudes, and may be susceptible to spoofing or other attacks. Thus, it is prudent to examine possible alternatives. Recently, star tracking has been of interest in global positioning. There are many implementations of a star tracker using an imaging-based optical system to capture star locations in order to estimate position using celestial navigation techniques. These imaging systems are performance limited by blurring imposed by atmospheric turbulence, platform jitter, and …

Modeling, Simulation And Control Of Hybrid Electric Vehicle Drive While Minimizing Energy Input Requirements Using Optimized Gear Ratios, Sanjai Massey

Dissertations, Master's Theses and Master's Reports

This project was conducted to analyze (model and simulate) and optimize an electric motor based drive system to propel a typical passenger vehicle in an urban driving environment. Although there are many HEV and EV type systems on the market today, this paper chose the Toyota Prius HEV system as a baseline using a brushless AC motor.

Although a vehicle can be driven many ways, a more standardized Urban Dynamometer Driving Schedule, UDDS, was chosen to simulate real driving conditions. This schedule is determined by the US Environmental Protection Agency, EPA, and is intended to represent the city driving conditions …

Scalable Integrated Circuit Simulation Algorithms For Energy-Efficient Teraflop Heterogeneous Parallel Computing Platforms, Lengfei Han

Dissertations, Master's Theses and Master's Reports

Integrated circuit technology has gone through several decades of aggressive scaling.It is increasingly challenging to analyze growing design complexity. Post-layout SPICE simulation can be computationally prohibitive due to the huge amount of parasitic elements, which can easily boost the computation and memory cost. As the decrease in device size, the circuits become more vulnerable to process variations. Designers need to statistically simulate the probability that a circuit does not meet the performance metric, which requires millions times of simulations to capture rare failure events.

Recent, multiprocessors with heterogeneous architecture have emerged as mainstream computing platforms. The heterogeneous computing platform can …

Autonomous Dc Microgrid With Self-Configurable Feasibility, Amir Farshad

Dissertations, Master's Theses and Master's Reports

Microgrids are power systems that work not only from the main power grid, but also in island mode operation. As each of the power sources and loads have voltage and current limitations, the autonomous microgrid should be able to control voltage and current levels while loads and sources are connected to the grid. Therefore, the microgrid bus voltage remains constant and power transfers safely.

To configure an autonomous microgrid, the load and source type identification comes to mind. An autonomous microgrid needs to know the type of the electrical components which are going to be connected to the grid. In …

Hardware Design And Integration And Software Programming For Optical Elastography, Nima Taherkhani

Dissertations, Master's Theses and Master's Reports

The elastic and viscoelastic properties of skin are a reflection of its health. Measurement of these elastic properties can be used as the indicator of various pathologies. The measurement concept in our works is to mechanically stimulate the skin with a low frequency pneumatic force using non-invasive means of deflecting the skin and use laser speckle to study the elasticity of the skin.

The goal of this work was to develop a setup for in vivo optical elastography of skin. This setup includes an electro-mechanical device which is able to deliver a sinusoidal pneumatic stimulus equivalent to 10 grams of …