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Full-Text Articles in Engineering
Formation Control Of Multiple Quadrotors, Miguel Alejandro Garcia
Formation Control Of Multiple Quadrotors, Miguel Alejandro Garcia
Theses and Dissertations
This thesis studies formation control of multiple quadrotors under different conditions. Two controller design approaches are proposed. In the first approach, it is assumed that the dynamics of each quadrotor is unknown and there is disturbance. With the aid of distributed estimation and the universal approximation property of neural networks, distributed tracking controllers are proposed. Simulation shows the effectiveness of the proposed controllers. In the second approach, it is assumed that the inertia parameters are unknown. With the aid of distributed estimation, online data estimation, and optimal control theory, distributed sub-optimal tracking controllers are proposed. Simulation results show the effectiveness …
Quantized State Simulation Of Electrical Power Systems, Joseph Micah Hood
Quantized State Simulation Of Electrical Power Systems, Joseph Micah Hood
Theses and Dissertations
An alternative is proposed to the current state-of-the-art simulation methods for the transient simulation of electrical power systems. The proposed method combines the Latency Insertion Method (LIM), the Quantized Discrete Event Specification (QDEVS), and the Quantized State System (QSS) method of integration. Using LIM, the power system state equations are decoupled in a way that allows the formulation of the system into a QDEVS-compliant model, which can then be directly solved with various QSS integration techniques. This combination of methods is called the Quantized DEVS-LIM method, or simply, QDL. A key feature of QDL is the asynchronous updates of all …
Closed Form Implicitly Integrated Models For Computationally Efficient Simulation Of Power Electronics, Andrew Wunderlich
Closed Form Implicitly Integrated Models For Computationally Efficient Simulation Of Power Electronics, Andrew Wunderlich
Theses and Dissertations
This work describes novel closed-form, implicitly integrated (CF-implicit) models of switched-mode power converters which feature implicit integration but require no iterative numerical solving algorithm for evaluation because they are explicitly solved prior to model execution. The derived models capture the large-signal dynamic behavior of the power converters, so their use and accuracy are not limited to any one set of operating conditions. These models can be implemented in any computational environment, including directly on an existing embedded controller as a digital twin. Since no iterative solver is required, the models are highly computationally efficient and have a very predictable worst-case …
The Matrix Revisited: A Critical Assessment Of Virtual Reality Technologies For Modeling, Simulation, And Training, George Demetrius Lecakes
The Matrix Revisited: A Critical Assessment Of Virtual Reality Technologies For Modeling, Simulation, And Training, George Demetrius Lecakes
Theses and Dissertations
A convergence of affordable hardware, current events, and decades of research have advanced virtual reality (VR) from the research lab into the commercial marketplace. Since its inception in the 1960s, and over the next three decades, the technology was portrayed as a rarely used, high-end novelty for special applications. Despite the high cost, applications have expanded into defense, education, manufacturing, and medicine. The promise of VR for entertainment arose in the early 1990's and by 2016 several consumer VR platforms were released. With VR now accessible in the home and the isolationist lifestyle adopted due to the COVID-19 global pandemic, …
The Wargaming Commodity Course Of Action Automated Analysis Method, William T. Deberry
The Wargaming Commodity Course Of Action Automated Analysis Method, William T. Deberry
Theses and Dissertations
This research presents the Wargaming Commodity Course of Action Automated Analysis Method (WCCAAM), a novel approach to assist wargame commanders in developing and analyzing courses of action (COAs) through semi-automation of the Military Decision Making Process (MDMP). MDMP is a seven-step iterative method that commanders and mission partners follow to build an operational course of action to achieve strategic objectives. MDMP requires time, resources, and coordination – all competing items the commander weighs to make the optimal decision. WCCAAM receives the MDMP's Mission Analysis phase as input, converts the wargame into a directed graph, processes a multi-commodity flow algorithm on …
Low Bandwidth Communication For Networked Power Hardware-In-The-Loop Simulation, Sean Borgsteede
Low Bandwidth Communication For Networked Power Hardware-In-The-Loop Simulation, Sean Borgsteede
Theses and Dissertations
Power-Hardware-In-the-Loop (PHIL) simulations allow the design and validation of power hardware components in virtual power system schemas with near real-time operation. This technique is increasingly used in the development cycle of many products to reduce design costs and increase design fidelity. The Hardware under Test (HuT) interfaces with a simulation of the user’s choosing through a hardware interface (HI). The digitally simulated system (DSS) runs on the real-time simulator before sending a reference value to the hardware interface to enforce. In this virtual to real interface, closed-loop stability and the simulation accuracy are the two paramount criteria in regards to …
Simulation Of Gan Based Mis Varactor, Bojidha Babu
Simulation Of Gan Based Mis Varactor, Bojidha Babu
Theses and Dissertations
This work deals with novel microwave switches based on III-Nitride varactors. RF switches, power limiters and other control devices are important components of various RF systems, such as wireless modules of laptops, tablets, cell phones etc., satellites communication systems, radars, multi-band wireless and aerospace communications, phased array antennas and so worth. Traditional RF switches are fabricated using pin diodes or MEMS, Si MOSFETs or GaAs HEMTs. These devices have a number of fundamental limitations. Si or GaAs based devices suffer from a low breakdown voltage and cannot handle high RF power. Pin-diodes require large forward currents and do not allow …
Applications Of Impedance Identification To Electric Ship System Control And Power Hardware-In-The-Loop Simulation, Jonathan Siegers
Applications Of Impedance Identification To Electric Ship System Control And Power Hardware-In-The-Loop Simulation, Jonathan Siegers
Theses and Dissertations
Recent advances in semiconductor technology, controls, and switching converter topologies have resulted in the increasing application of power electronics in power distribution systems. Power electronic enabled distribution systems have inspired a renewed interest in DC distribution architectures as an appealing alternative to traditional AC methods due to the significant performance and efficiency gains they offer. However, the notional power electronic based DC distribution system is a complex and extensively interconnected system consisting of multiple power converters. As a result, a number of system-level challenges related to stability arise due to interaction among multiple power converters. In addition, the power distribution …
Verifying Molecular Dynamics Using Dielectric Spectroscopy, Joshua Dee Smith
Verifying Molecular Dynamics Using Dielectric Spectroscopy, Joshua Dee Smith
Theses and Dissertations
The electrical properties of proteins in solution are important for their structure and function. Computational biophysics studies of proteins need accurate parameters to ensure that numerical simulations match physical reality. Past work in this eld has compared the electrical properties of proteins obtained from dielectric spectroscopy to numerical simulations of proteins in water with adjustment of pKa values to try to capture the inevitable changes in electrical conformation that will occur in a complex structure such as a folded protein. However, fundamental veri cation of the charge parameters of the amino acid building blocks in common molecular dynamics software packages …
A Flexible Infrastructure For Multi-Agent Systems, Gerrit Addison N Sorensen
A Flexible Infrastructure For Multi-Agent Systems, Gerrit Addison N Sorensen
Theses and Dissertations
Multi-Agent coordination and control has been studied for a long time, but has recently gained more interest because of technology improvements allowing smaller, more versatile robots and other types of agents. To facilitate multi-agent experiments between heterogeneous agents, including robots and UAVs, we have created a test-bed with both simulation and hardware capabilities. This thesis discusses the creation of this unique, versatile test-bed for multi-agent experiments, also a unique graph creation algorithm, and some experimental results obtained using the test-bed.
The Effect Of Registration Errors On Tracking In A Networked Radar System, Bradley J. Mortenson
The Effect Of Registration Errors On Tracking In A Networked Radar System, Bradley J. Mortenson
Theses and Dissertations
To successfully combine information from distributed radar sensors, it is essential that each sensor be correctly referenced in a global coordinate system. If there are biases in the reported position of these sensors, the reported target position will also be biased and the ensuing global estimate of the target position will be degraded. Furthermore, any biases in range or azimuth measurements of these sensors will likewise be reflected in the degradation of global estimate of target position. Registration is the process of ensuring that these errors do not result in the creation of an additional redundant target when only a …
Global Positioning System (Gps) Receiver Design For Multipaths Mitigation, El-Sayed Abdel-Salam Gadallah
Global Positioning System (Gps) Receiver Design For Multipaths Mitigation, El-Sayed Abdel-Salam Gadallah
Theses and Dissertations
Multipath effects are a source of error degrading the accuracy of DGPS signal processing. The statistical models of multipath are determined by user location and, in addition are time varying. There is no unified statistical model for the multipath signal. Therefore the solution of the multipath problem using statistical models is difficult. This research introduces a new estimator that can detect the presence of multipath, can determine the unknown number of multipath components and can estimate multipath parameters in the GPS receiver (time delay and attenuation coefficients). Furthermore the multipath signal parameters are estimated at any instant of observation. The …
Effects Of Clutter Height Distribution On Adaptive Clutter Erasure Performance, Kelce Steven Wilson
Effects Of Clutter Height Distribution On Adaptive Clutter Erasure Performance, Kelce Steven Wilson
Theses and Dissertations
A new real beam interferometric processing technique, called Adaptive Clutter Erasure (ACE), is investigated for applicability to ground clutter suppression in airborne radar systems. By analysis and simulation, the viability of the ACE concept as a next generation clutter suppression technique is demonstrated to achieve performance enhancements commensurate with currently implemented techniques. Research results indicate the ACE concept provides a reliably consistent 10dB Signal-to-Clutter Ratio (SCR) advantage over the APG-63, an operational radar system used for baseline comparison. ACE system concept development and performance predictions are conducted in conformity with the physical and operational design parameters of the APG-63, namely …
Visualization And Animation Of A Missile/Target Encounter, Jeffrey T. Bush
Visualization And Animation Of A Missile/Target Encounter, Jeffrey T. Bush
Theses and Dissertations
Existing missile/target encounter modeling and simulation systems focus on improving probability of kill models. Little research has been done to visualize these encounters. These systems can be made more useful to the engineers by incorporating current computer graphics technology for visualizing and animating the encounter. Our research has been to develop a graphical simulation package for visualizing both endgame and full fly-out encounters. Endgame visualization includes showing the interaction of a missile, its fuze cone proximity sensors, and its target during the final fraction of a second of the missile/target encounter. Additionally, this system displays dynamic effects such as the …
A Single Chip Low Power Implementation Of An Asynchronous Fft Algorithm For Space Applications, Bruce W. Hunt
A Single Chip Low Power Implementation Of An Asynchronous Fft Algorithm For Space Applications, Bruce W. Hunt
Theses and Dissertations
A fully asynchronous fixed point FFT processor is introduced for low power space applications. The architecture is based on an algorithm developed by Suter and Stevens specifically for a low power implementation. The novelty of this architecture lies in its high localization of components and pipelining with no need to share a global memory. High throughput is attained using large numbers of small, local components working in parallel. A derivation of the algorithm from the discrete Fourier transform is presented followed by a discussion of circuit design parameters specifically, those relevant to space applications. The generic architecture is explained with …