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Modeling And Control Of Fuel Cell-Battery Hybrid Energy Sources, Nima Lotfi

Doctoral Dissertations

"Environmental, political, and availability concerns regarding fossil fuels in recent decades have garnered substantial research and development in the area of alternative energy systems. Among various alternative energy systems, fuel cells and batteries have attracted significant attention both in academia and industry considering their superior performances and numerous advantages. In this dissertation, the modeling and control of these two electrochemical sources as the main constituents of fuel cell-battery hybrid energy sources are studied with ultimate goals of improving their performance, reducing their development and operational costs and consequently, easing their widespread commercialization. More specifically, Paper I provides a comprehensive background …

Design, Manufacturing And Control Of An Advanced High-Precision Robotic System For Microsurgery, Arezoo Ebrahimi

Electronic Theses and Dissertations

Microsurgeries like ophthalmic surgery confront many challenges like limited workspace and hand motion, steady hand movements, manipulating delicate thin tissues, and holding the instrument in place for a long time. New developments in robotically-assisted surgery can highly benefits this field and facilitate those complicated surgeries. Robotic eye surgery can save time, reduce surgical complications and inspire more delicate surgical procedures that cannot be done currently by surgeon’s hands. In this thesis work, the requirements for ophthalmic surgeries were studied and based on that a robotic system with 6 DOF is proposed and designed. This robotic

system is capable of handling …

Dcpp/Polygait Inventory Control System, Logan Pace, Robert Garlinghouse

Industrial and Manufacturing Engineering

This report discusses a proposed system to improve upon inventory management issues experienced in the M&TE Tool room for the PG&E Diablo Canyon Power plant. Effective inventory tracking and management is an important characteristic of any organization handling physical assets, and without the proper system in place, companies may lose expensive items and waste time by not having equipment available when needed. The tool room is experiencing inventory shrinkage of M&TE equipment nearing $100,000 per year largely because of an inefficient checkout system that fails to keep employees accountable for the tools they check out. Even more costly than the …

Investigation Of Distributed Model Predictive Control For Economic Load Shifting In Building Hvac Systems, Peter Kinsella

Theses and Dissertations

One of the major challenges that building owners and operators face is maintaining a low cost of operation. In certain markets within the U.S., electrical cost varies throughout the day; it is higher during times of peak demand. This leaves the customer the incentive to cut back electrical use during peak demand periods. Since 40% of the peak electrical demand is due to the operation of the building HVAC system alone, the opportunity exists for shifting the building cooling load to off-peak hours. This can be done by pre-cooling the space, thereby using the building mass as a sort of …

Ubot-7: The Design Of A Compliant Dexterous Mobile Manipulator, Jonathan Cummings

Masters Theses

This thesis presents the design of uBot-7, the latest version of a dexterous mobile manipulator. This platform has been iteratively developed to realize a high performance-to-cost dexterous whole body manipulator with respect to mobile manipulation. The semi-anthropomorphic design of the uBot is a demonstrated and functional research platform for developing advanced autonomous perception, manipulation, and mobility tasks. The goal of this work is to improve the uBot’s ability to sense and interact with its environment in order to increase the platforms capability to operate dexterously, through the incorporation of joint torque feedback, and safely, through the implementation of passive and …

Control Of A Spacecraft Using Mixed Momentum Exchange Devices, Blake J. Currie

Master's Theses

Hardware configurations, a control law, and a steering law are developed for a mixed hardware spacecraft that uses both control moment gyros and reaction wheels. Replacing one or more gyros in a spacecraft with a reaction wheel has potential for cost savings while still achieving much greater performance than using reaction wheels alone. Several simulated tests are run to compare the performance to a traditional all reaction wheel or all control moment gyro spacecraft, including analysis of failure modes and singular configurations. The mixed system performed similarly to all gyro systems, responding within 6% of the gyro system’s time for …

Feedback Speed Control Of A Small Two-Stroke Internal Combustion Engine That Propels An Unmanned Aerial Vehicle, Paul D. Fjare

UNLV Theses, Dissertations, Professional Papers, and Capstones

Unmanned aerial vehicles (UAV) require intelligent control of their power source. Small UAV are typically powered by electric motors or small two-stroke internal combustion (IC) engines. Small IC engines allow for longer flight times but are more difficult to control and cause significant ground noise. A hybrid operation that uses the engine at high altitudes and the electric motors at low altitudes is desired. This would allow for extended flight with acceptable ground noise levels. Since the engine can not be restarted in the air it must be able to remain at idle for an extended time without stalling. A …

Laboratory Apparatus For Gas Turbine Combustion Development, Dustin Lee Cruise

Open Access Theses

The next generation of combustor technology will be required to meet the demands of a world more focused on greenhouse gases and global warming. Due to this new focus on emission control, combustors must produce less NO x , while operating in a higher pressure environment that is more prone to combustion instabilities.

This work focuses on the development of a lab and combustor that will be used for the next generation combustor development. The lab development includes layout and organization, facilities, measurement and instrumentation, automation of the testing process, and an imaging tool for diagnostics.

A Lean Direction Injection …

Kinesthetic Haptics Sensing And Discovery With Bilateral Teleoperation Systems, Tian Qiu

Doctoral Dissertations

In the mechanical engineering field of robotics, bilateral teleoperation is a classic but still increasing research topic. In bilateral teleoperation, a human operator moves the master manipulator, and a slave manipulator is controlled to follow the motion of the master in a remote, potentially hostile environment. This dissertation focuses on kinesthetic perception analysis in teleoperation systems. Design of the controllers of the systems is studied as the influential factor of this issue. The controllers that can provide different force tracking capability are compared using the same experimental protocol. A 6 DOF teleoperation system is configured as the system testbed. An …

Modeling, Analysis, And Control Of A Mobile Robot For In Vivo Fluoroscopy Of Human Joints During Natural Movements, Matthew A. Young

Doctoral Dissertations

In this dissertation, the modeling, analysis and control of a multi-degree of freedom (mdof) robotic fluoroscope was investigated. A prototype robotic fluoroscope exists, and consists of a 3 dof mobile platform with two 2 dof Cartesian manipulators mounted symmetrically on opposite sides of the platform. One Cartesian manipulator positions the x-ray generator and the other Cartesian manipulator positions the x-ray imaging device. The robotic fluoroscope is used to x-ray skeletal joints of interest of human subjects performing natural movement activities. In order to collect the data, the Cartesian manipulators must keep the x-ray generation and imaging devices accurately aligned while …

Thermal And Cooling Systems Modeling Of Powertrain For A Plug -In Parallel-Through-The-Road Hybrid Electric Vehicle, Mengjia Cao

Wayne State University Theses

Thermal modeling and control play an ever increasing role with hybrid electric vehicle (HEV) design and development for improving overall vehicle energy efficiency, and to account for additional thermal loading from electric powertrain components such as electric motor, motor controller and battery pack.

This thesis presents a complete development process for an efficient modeling approach with integrated control strategy for the thermal management of plug-in HEV in a parallel-through-the road (PTTR) architecture, adopted by Wayne State University Hybrid Warriors for their Department of Energy's EcoCAR2 Plugging in to the Future Competition.

The frameworks of this project include simulating the thermal …

Wind Turbine Controls For Farm And Offshore Operation, Zhongzhou Yang

Theses and Dissertations

Development of advanced control techniques is a critical measure for reducing the cost of energy for wind power generation, in terms of both enhancing energy capture and reducing fatigue load. There are two remarkable trends for wind energy. First, more and more large wind farms are developed in order to reduce the unit-power cost in installation, operation, maintenance and transmission. Second, offshore wind energy has received significant attention when the scarcity of land resource has appeared to be a major bottleneck for next level of wind penetration, especially for Europe and Asia. This dissertation study investigates on several wind turbine …

Techniques For Optimum Design Of Actively Controlled Structures Including Topological Considerations, Arjumand Ali

Theses and Dissertations

The design and performance of complex engineering systems often depends on several conflicting objectives which, in many cases, cannot be represented as a single measure of performance. This thesis presents a multi-objective formulation for a comprehensive treatment of the structural and topological considerations in the design of actively controlled structures.

The dissertation addresses three main problems. The first problem deals with optimum placement of actuators in actively controlled structures. The purpose of control is to reduce the vibrations when the structure is subjected to a disturbance. In order to mitigate the structural vibrations as quickly as possible, it is necessary …

Architectural Engineering Earthquake Shake Table, Garrett Gudgel, John Whitmer, Brandan Williams

Mechanical Engineering

The Architectural Engineering Department at California Polytechnic State University, San Luis Obispo, owns and operates a single-axis earthquake shake table that previously was only capable of basic wave motion. After implementing a computer based interface to the existing system, Mechanical Engineering student seniors were able to create control algorithms that can take existing or user created acceleration data from earthquakes as well as any user defined position data to be accurately run on the earthquake shake table.

Closed Loop Control Of A Cylindrical Tube Type Ionic Polymer Metal Composite (Ipmc), Benjamin Mead

UNLV Theses, Dissertations, Professional Papers, and Capstones

The goal of this research is to provide a framework for the integration of tube type, cylindrical Ionic Polymer Metal-Composite (IPMC) into conventional devices. IPMCs are one of the most widely used types of electro-active polymer actuator, due to their low electric driving potential and large deformation range. For this research a tube type IPMC was investigated. This IPMC has a circular cross section with four separate electrodes on its surface and a hole through the middle. The four electrodes allow for biaxial bending and accurate control of the tip location. One of the main advantages of using this type …

Adaptive Nonlinear Control For Autonomous Ground Vehicles, William Spencer Black

Open Access Theses

We present the background and motivation for ground vehicle autonomy, and focus on uses for space-exploration. Using a simple design example of an autonomous ground vehicle we derive the equations of motion. After providing the mathematical background for nonlinear systems and control we present two common methods for exactly linearizing nonlinear systems, feedback linearization and backstepping. We use these in combination with three adaptive control methods: model reference adaptive control, adaptive sliding mode control, and extremum-seeking model reference adaptive control. We show the performances of each combination through several simulation results. We then consider disturbances in the system, and design …

An Experimental Investigation On The Control Of Tip Vortices From Wind Turbine Blade, Zhe Ning

Browse all Theses and Dissertations

Wind turbine dynamics, wake effects and environmental impacts have been identified the most significant research topics needed for wind resource characterization and wind power generation. Among these issues, tip vortices generated from the blade tip have been recognized as a substantial resource for the turbulent wake flow as well as the aerodynamic noise emission from a wind turbine. An experimental study is conducted to characterize the evolution of the tip vortices downstream of a well-designed horizontal axis wind turbine (HAWT) model. In addition to measuring dynamic wind loads (both aerodynamic forces and moments) and power output from the wind turbine …

Mechanistic Analysis And Reduced Order Modeling Of Forced Film Cooling Flows, Guillaume Francois Bidan

LSU Doctoral Dissertations

Abstract Unforced and forced film cooling jets are investigated in view to develop a reduced order model of the velocity and temperature fields. First, a vertical jet in cross-flow, a configuration well documented at high blowing ratios, is investigated at low blowing ratios using experimental visualizations and large eddy simulations. The unforced study reveals that dominant structures at low blowing ratio can be significantly different from the ones formed at high blowing ratio and describes their evolution and transition as the blowing ratio is changed. The forced jet investigations extend the results of past numerical studies in terms of starting …

Investigation And Implementation Of A Robust Temperature Control Algorithm For Friction Stir Welding, Kenneth A. Ross

Theses and Dissertations

In friction stir welding, the temperature of the process zone affects the properties of the resulting weld and has a dramatic effect on tool life in PCBN (polycrystalline cubic boron nitride) tools. Therefore an active control system that changes process parameters to control weld temperature is desirable. Mayfield and Sorensen proposed a two-stage control model that contains an inner loop that controls the spindle speed to keep power constant and an outer loop for setting the desired power based on weld temperature. This work contains the analysis and implementation of a temperature control method based on their work. This research …

Control Of A Robotic Prototype Multi-Axis Synergistic System, Julio A. Torres

Open Access Theses & Dissertations

Balance is an ability that every person has and uses in normal daily life, to walk, run, stand, dance, etc. However, there are people who suffer a kind of balance impairment. The Computerized Dynamic Posturography (CDP) is technique in balance rehabilitation, where the patient is asked to stand on a moving platform that is equipped with sensors that measure how well you maintain your balance. In this thesis, a new CDP mechatronic system, the Multi-Axis Synergistic System (MASS), for balance assessment is being developed.

As a first stage and as the objective of this research work the transferable control algorithm …

Development Of The Control And Ignition Systems On A High Pressure Gas Turbine Combustor, Carlos Alejandro Valdez

Open Access Theses & Dissertations

The ignition and control systems of a laboratory scale high-pressure gas turbine combustor were developed in the present work. This work provides a detailed description of the design, development and testing of the remote control system developed for a High Pressure Gas Turbine Combustor (HPTC).

The combustor has the capability to operate at pressures up to 1.5 MPa and temperatures up to 2400 K. It is also designed for a maximum air and fuel flow rates of 81.93 g/s and 35.77 g/s respectively. The fuel used will be CH4 for the early experiments but it is designed to operate using …

Instrumentation, Control And Torch Ignition Systems Development For Lox/Methane Propulsion Research, Jesus Betancourt-Roque

Open Access Theses & Dissertations

A liquid propulsion research facility has been developed at the Center for Space Exploration Technology Research at The University of Texas at El Paso. This facility has capabilities for producing up to 25 liters of Liquid Methane, feeding LOX/Methane propellants to 100 N class thrusters and conducting automated steady state and pulsing combustion experiments. This work describes the design, development and testing process of the Data Acquisition and Remote Control System developed to integrate an Altitude Simulation System, a Cryogenic Delivery System, and multiple rocket combustors and thrusters. A Torch Ignition System development is detailed as well as the evaluation …

Applied Control Strategies At A Cogeneration Plant, Joseph William Burns

Master's Theses

The purpose of this paper is to demonstrate the effectiveness of “classical strategies for dynamic control” on authentic cogeneration processes. These strategies are applied to several processes at the University of Connecticut’s cogeneration plant. Case studies of their applications are presented in this paper. Strategies that are applied include the following:

1) The classical SISO feedback structure

2) The First Order Plus Dead Time (FOPDT) process model

3) The Internal Model Control (IMC) correlations for PI controller tuning

4) Static feed forward with feedback trim

5) Cascade Control

Control And Coordination In A Networked Robotic Platform, Krishna Chaitanya Kalavacharla

Masters Theses

Control and Coordination of the robots has been widely researched area among the swarm robotics. Usually these swarms are involved in accomplishing tasks assigned to them either one after another or concurrently. Most of the times, the tasks assigned may not need the entire population of the swarm but a subset of them. In this project, emphasis has been given to determination of such subsets of robots termed as ”flock” whose size actually depends on the complexity of the task. Once the flock is determined from the swarm, leader and follower robots are determined which accomplish the task in a …

Energy-Economical Heuristically Based Control Of Compass Gait Walking On Stochastically Varying Terrain, Christian Hubicki

Master’s Theses

Investigation uses simulation to explore the inherent tradeoffs ofcontrolling high-speed and highly robust walking robots while minimizing energy consumption. Using a novel controller which optimizes robustness, energy economy, and speed of a simulated robot on rough terrain, the user can adjust their priorities between these three outcome measures and systematically generate a performance curveassessing the tradeoffs associated with these metrics.

Robust Observers And Controllers For Marine Surface Vessels Undergoing Maneuvering And Course-Keeping Tasks, Nassim Khaled

Wayne State University Dissertations

The dynamic behavior of marine surface vessels is highly nonlinear. Moreover, it is significantly influenced by environmental disturbances induced by winds, random sea waves and currents. To yield a desired response of the ship, the guidance and control system of the ship should be robust to both modeling imprecision and significant environmental disturbances.

The focus of the current work is threefold. First, a six degree-of-freedom nonlinear model for a marine surface vessel is developed. It accounts for the coriolis and centripetal acceleration terms, added mass and wave damping terms, wave excitation forces, so-called "memory" effect terms, nonlinear restoring forces, wind …

A Comparative Study On Fault Detection And Self-Reconfiguration, Ning Ge

ETD Archive

Extended State Observer (ESO) and the Alpha-Beta-Gamma Tracker are introduced and compared. In comparison, the ESO is found to be more noise resistant. The extended state used for the estimation of the general system dynamics in real time makes it suitable for fault detection. Four control schemes are proposed for self-reconfiguration upon fault detection. These schemes are Active Disturbance Rejection Control, Tracker-based Feedback Control, Fuzzy Logic Control and Tracker-based PID Control. To compare their control performance, these schemes are applied to three different applications namely Active Engine Vibration Isolation System, Three-Tank Dynamic System and MEMS Gyroscope System. The advantages and …

Development Of A Particle Flow Test For Rotational Molding, Russell B. Whatcott

Theses and Dissertations

One of the current testing method (the Dry Flow test) to qualify resin for use in production in the rotomolding process has been shown to have many flaws in both equipment and procedure. Research was done here to investigate a possible alternative that could eliminate some of these testing deficiencies. By reducing equipment and operator errors, the testing of materials becomes more valuable of an exercise. The Angular Flow test developed in this research can increase repeatability. By coming to understand the rotational molding process better, an evaluation that can give more valid information was devised.

Active Minimization Of Acoustic Energy Density To Attenuate Radiated Noise From A Diesel Generator, Andrew J. Boone

Theses and Dissertations

The focus of this thesis was to use active noise control (ANC) to globally minimize the tonal and broadband noise radiating from a diesel generator enclosure. The major goal of this research was to show that minimizing the noise within the enclosure can lead to an overall sound pressure level (SPL) reduction of radiated noise. The target levels for overall SPL reduction were at least 2 dBA. The control algorithms used in this research were based on a filtered-x LMS adaptive algorithm, which minimizes energy density (ED). Both feedforward and feedback control approaches were investigated. The noise spectrum produced by …

Settling-Time Improvements In Positioning Machines Subject To Nonlinear Friction Using Adaptive Impulse Control, Tim Hakala

Theses and Dissertations

A new method of adaptive impulse control is developed to precisely and quickly control the position of machine components subject to friction. Friction dominates the forces affecting fine positioning dynamics. Friction can depend on payload, velocity, step size, path, initial position, temperature, and other variables. Control problems such as steady-state error and limit cycles often arise when applying conventional control techniques to the position control problem. Studies in the last few decades have shown that impulsive control can produce repeatable displacements as small as ten nanometers without limit cycles or steady-state error in machines subject to dry sliding friction. These …