Open Access. Powered by Scholars. Published by Universities.®

Controls and Control Theory Commons

Open Access. Powered by Scholars. Published by Universities.®

656 Full-Text Articles 718 Authors 409484 Downloads 39 Institutions

All Articles in Controls and Control Theory

Faceted Search

656 full-text articles. Page 1 of 23.

Robust Feedback Control Based On Low Order Models With Uncertainty Estimation For A Class Of Biomedical Problems, Hector Puebla, Miguel A. Gutierrez-Limon, Eliseo Hernandez-Martinez, Alejandra Velasco-Perez 2016 Universidad Autonoma Metropolitana

Robust Feedback Control Based On Low Order Models With Uncertainty Estimation For A Class Of Biomedical Problems, Hector Puebla, Miguel A. Gutierrez-Limon, Eliseo Hernandez-Martinez, Alejandra Velasco-Perez

Annual Symposium on Biomathematics and Ecology: Education and Research

No abstract provided.


Synchronization Of Coupled Neurons Via Robust Feedback, Hector Puebla, Ricardo Aguilar-Lopez, Priti Kumar Roy 2016 Universidad Autonoma Metropolitana

Synchronization Of Coupled Neurons Via Robust Feedback, Hector Puebla, Ricardo Aguilar-Lopez, Priti Kumar Roy

Annual Symposium on Biomathematics and Ecology: Education and Research

No abstract provided.


Control System Research And Development To Support Virtual Prototyping Of Pump And Motors, Rajith Weerasinghe, Monika Ivantysynova, Paul Kalbfleisch 2016 Purdue University

Control System Research And Development To Support Virtual Prototyping Of Pump And Motors, Rajith Weerasinghe, Monika Ivantysynova, Paul Kalbfleisch

The Summer Undergraduate Research Fellowship (SURF) Symposium

Virtual prototyping of positive pumps and motors is incredibly useful, increasing speed of development and lowering cost. The calculations of fluids discharge pressure, displaced by a swashplate-type-axial piston pump/motor is dependent on the load impedance driven by the unit. The load impedance is estimated by a variable orifice found downstream of the unit. Similarly, the suction line impedance is also estimated with an orifice. The current project aims to evaluate the various loading architectures in their ability to quickly and accurately create the desired impedance. The robustness of the loading architectures was tested on a wide range of pump ...


Optimization-Free Optical Focal Field Engineering Through Reversing The Radiation Pattern From A Uniform Line Source, Yanzhong Yu, Qiwen Zhan 2016 University of Dayton

Optimization-Free Optical Focal Field Engineering Through Reversing The Radiation Pattern From A Uniform Line Source, Yanzhong Yu, Qiwen Zhan

Qiwen Zhan

A simple and flexible method is presented for the generation of optical focal field with prescribed characteristics. By reversing the field pattern radiated from a uniform line source, for which the electric current is constant along its extent, situated at the focus of a 4Pi focusing system formed by two confocal high-NA objective lenses, the required illumination distribution at the pupil plane for creating optical focal field with desired properties can be obtained. Numerical example shows that an arbitrary length optical needle with extremely high longitudinal polarization purity and consistent transverse size of ~0.36λ over the entire depth of ...


Tailoring Optical Complex Fields With Nano-Metallic Surfaces, Guanghao Rui, Qiwen Zhan 2016 University of Dayton

Tailoring Optical Complex Fields With Nano-Metallic Surfaces, Guanghao Rui, Qiwen Zhan

Qiwen Zhan

Recently there is an increasing interest in complex optical fields with spatially inhomogeneous state of polarizations and optical singularities. Novel effects and phenomena have been predicted and observed for light beams with these unconventional states. Nanostructured metallic thin film offers unique opportunities to generate, manipulate and detect these novel fields. Strong interactions between nano-metallic surfaces and complex optical fields enable the development of highly compact and versatile functional devices and systems. In this review, we first briefly summarize the recent developments in complex optical fields. Various nano-metallic surface designs that can produce and manipulate complex optical fields with tailored characteristics ...


Creation Of Identical Multiple Focal Spots With Prescribed Axial Distribution, Yanzhong Yu, Qiwen Zhan 2016 University of Dayton

Creation Of Identical Multiple Focal Spots With Prescribed Axial Distribution, Yanzhong Yu, Qiwen Zhan

Qiwen Zhan

We present a scheme for the construction of coaxially equidistant multiple focal spots with identical intensity profiles for each individual focus and a predetermined number and spacing. To achieve this, the radiation field from an antenna is reversed and then gathered by high numerical aperture objective lenses. Radiation patterns from three types of line sources, i.e., the electric current, magnetic current and electromagnetic current distributions, with cosine-squared taper are respectively employed to generate predominately longitudinally polarized bright spots, azimuthally polarized doughnuts, and focal spots with a perfect spherically symmetric intensity distribution. The required illuminations at the pupil plane of ...


Delay-Independent Stability Analysis Of Linear Time-Delay Systems Based On Frequency, Xianwei Li, Huijun Gao, Keqin Gu 2016 Harbin Institute of Technology

Delay-Independent Stability Analysis Of Linear Time-Delay Systems Based On Frequency, Xianwei Li, Huijun Gao, Keqin Gu

SIUE Faculty Research, Scholarship, and Creative Activity

This paper studies strong delay-independent stability of linear time-invariant systems. It is known that delay-independent stability of time-delay systems is equivalent to some frequency-dependent linear matrix inequalities. To reduce or eliminate conservatism of stability criteria, the frequency domain is discretized into several sub-intervals, and piecewise constant Lyapunov matrices are employed to analyze the frequency-dependent stability condition. Applying the generalized Kalman–Yakubovich–Popov lemma, new necessary and sufficient criteria are then obtained for strong delay-independent stability of systems with a single delay. The effectiveness of the proposed method is illustrated by a numerical example.


Stochastic And Optimal Distributed Control For Energy Optimization And Spatially Invariant Systems, Jin Dong 2016 University of Tennessee, Knoxville

Stochastic And Optimal Distributed Control For Energy Optimization And Spatially Invariant Systems, Jin Dong

Doctoral Dissertations

Improving energy efficiency and grid responsiveness of buildings requires sensing, computing and communication to enable stochastic decision-making and distributed operations. Optimal control synthesis plays a significant role in dealing with the complexity and uncertainty associated with the energy systems.

The dissertation studies general area of complex networked systems that consist of interconnected components and usually operate in uncertain environments. Specifically, the contents of this dissertation include tools using stochastic and optimal distributed control to overcome these challenges and improve the sustainability of electric energy systems.

The first tool is developed as a unifying stochastic control approach for improving energy efficiency ...


Cal Poly Supermileage Electronic Fuel Injection, Alexander Pink 2016 California Polytechnic State University, San Luis Obispo

Cal Poly Supermileage Electronic Fuel Injection, Alexander Pink

Electrical Engineering

Cal Poly Supermileage is a student-run engineering club that builds prototype gasoline vehicles optimized maximum fuel-efficiency. To power their vehicles, the Supermileage team makes use of single-cylinder, 4-stroke, electronically fuel-injected (EFI) gasoline engines. This report details the development, iterative design & test cycles, and integration of an EFI system for the Supermileage club. This project develops an EFI system that interfaces to the most common types of sensors found in the low-power Supermileage-range of engines, including throttle-position sensors, manifold absolute pressure sensors, gear-tooth hall-effect sensors, variable-reluctance position sensors, engine coolant temperature sensors, intake air temperature sensors, and exhaust oxygen sensors. This ...


A Stroke Therapy Brace Design, Evan Kirkbride 2016 California Polytechnic State University, San Luis Obispo

A Stroke Therapy Brace Design, Evan Kirkbride

Electrical Engineering

Victims of stroke often have difficulty with rehabilitation. With limited movement on their affected arm, patients often do not want to move much for physical therapy. In this project, we design a robotic brace that helps stroke patients move their arm more effectively in a reaching or pulling motion. By giving patients more movement in their affected arm than they would have otherwise, patients gain more from rehabilitation. The brace also adapts to the patient’s needs, providing more inclination or resistance as needed for their physical therapy. This kind of therapy engages patients rather than relying on their likely ...


Automatic Water Pump Controller, Alam D. Salguero, Kyle Russell Marquez Weeks 2016 California Polytechnic State University, San Luis Obispo

Automatic Water Pump Controller, Alam D. Salguero, Kyle Russell Marquez Weeks

Electrical Engineering

In countries including Indonesia, Mexico, Guatemala, and El Salvador, a city water authority supplies the clean water and pumps it into large ground-level storage tanks. A resident’s water pump then pumps the water to a water tank on top of his/her house. When the water level in the ground-level storage tank becomes too low, the pump siphons air and shuts down, requiring a resident to manually prime the water pump to get it running again. Residents struggle to monitor the water level of the tanks effectively and keep the pump running properly. To remedy the issue, the Automatic ...


How Can Occupancy Modeling And Occupancy Sensors Reduce Energy Usage In Academic Buildings: An Application Approach To University Of San Francisco, Paloma R. Duong 2016 University of San Francisco

How Can Occupancy Modeling And Occupancy Sensors Reduce Energy Usage In Academic Buildings: An Application Approach To University Of San Francisco, Paloma R. Duong

Master's Projects

Buildings are amongst the highest energy consumers relative to industry and transportation. They account for 40% of the world’s energy consumption, due to the need for lighting, equipment, heating, cooling and ventilation. Academic buildings are multi-purpose buildings that create a challenge on energy reduction. Most are old and have fixed occupancy schedules, resulting in high energy consumption because these buildings experience significant occupancy variation throughout the day. Five academic buildings were analyzed; their building information, energy consumption data and methods to project energy savings have been analyzed. The case studies presented different strategies on predicting energy savings, but these ...


Simulation And Performance Evaluation Of Algorithms For Unmanned Aircraft Conflict Detection And Resolution, Jeffrey H. Ledet 2016 University of New Orleans

Simulation And Performance Evaluation Of Algorithms For Unmanned Aircraft Conflict Detection And Resolution, Jeffrey H. Ledet

University of New Orleans Theses and Dissertations

The problem of aircraft conflict detection and resolution (CDR) in uncertainty is addressed in this thesis. The main goal in CDR is to provide safety for the aircraft while minimizing their fuel consumption and flight delays. In reality, a high degree of uncertainty can exist in certain aircraft-aircraft encounters especially in cases where aircraft do not have the capabilities to communicate with each other. Through the use of a probabilistic approach and a multiple model (MM) trajectory information processing framework, this uncertainty can be effectively handled. For conflict detection, a randomized Monte Carlo (MC) algorithm is used to accurately detect ...


Development Of A Digital Offset Laser Lock, Ian W. Hage 2016 College of William and Mary

Development Of A Digital Offset Laser Lock, Ian W. Hage

College of William & Mary Undergraduate Honors Theses

An offset laser lock is an optoelectronic system capable of stabilizing a laser's optical frequency to a variable offset from another stable laser's frequency. The lock system described in this report relies on a digital frequency comparison of the beat note of two lasers to determine and fix the frequency difference, or offset, between them. This thesis describes the construction of a configurable proportional-integral (PI) control circuit to regulate a laser's frequency based on the error signal generated by a digital comparison of the beat note frequency, as well as the integration of formerly unconnected circuit elements ...


Led Street Light Research Project Part Ii: New Findings, Stephen Quick, Donald K. Carter, Kayvon Fatahalian, Cynthia Limauro, C+C Lighting 2016 Carnegie Mellon University

Led Street Light Research Project Part Ii: New Findings, Stephen Quick, Donald K. Carter, Kayvon Fatahalian, Cynthia Limauro, C+C Lighting

School of Architecture

Many cities are converting their existing street lighting to Light Emitting Diode (LED) source luminaires due to anticipated energy savings of 40 to 80 percent, as compared to high intensity discharge (HID) source luminaires, and maintenance savings estimated to be 50 to 75 percent due to the longer life of LED luminaires. Addressable electronic lighting controls and sensors are now available that can transform a basic streetlight into an intelligent, smart city device with public safety and other benefits. The number of variables that civic officials must consider for any street lighting conversion project has increased as a result of ...


Dynamic Extruder Control For Polymer Printing In Big Area Additive Manufacturing, Alex Christopher Roschli 2016 University of Tennessee - Knoxville

Dynamic Extruder Control For Polymer Printing In Big Area Additive Manufacturing, Alex Christopher Roschli

Masters Theses

Big Area Additive Manufacturing (BAAM) is 3D Printing on a large scale and can be used to create structures on the scale of cars and houses. Scaling up 3D printing to BAAM size meant fundamentally altering the traditional fused deposition modeling process by switching from a filament to a pellet material feed. This meant switching from a stepper motor extruder to a servo driven screw extruder. While increasing the throughput of the system, this new extruder increases the overall complexity. Effective control of the system is paramount to the success of BAAM enabling it to effectively scale in speed in ...


A Radial Basis Function Method For Solving Optimal Control Problems., Hossein Mirinejad 2016 University of Louisville

A Radial Basis Function Method For Solving Optimal Control Problems., Hossein Mirinejad

Electronic Theses and Dissertations

This work presents two direct methods based on the radial basis function (RBF) interpolation and arbitrary discretization for solving continuous-time optimal control problems: RBF Collocation Method and RBF-Galerkin Method. Both methods take advantage of choosing any global RBF as the interpolant function and any arbitrary points (meshless or on a mesh) as the discretization points. The first approach is called the RBF collocation method, in which states and controls are parameterized using a global RBF, and constraints are satisfied at arbitrary discrete nodes (collocation points) to convert the continuous-time optimal control problem to a nonlinear programming (NLP) problem. The resulted ...


Sensorless Rotor Position Estimation For Brushless Dc Motors, Iram G. Raza 2016 The University of Western Ontario

Sensorless Rotor Position Estimation For Brushless Dc Motors, Iram G. Raza

Electronic Thesis and Dissertation Repository

Brushless DC motor speed is controlled by synchronizing the stator coil current with rotor position in order to acquire an accurate alignment of stator rotating field with rotor permanent-magnet field for efficient transfer of energy. In order to accomplish this goal, a motor shaft is instantly tracked by using rotating rotor position sensors such as Hall effect sensors, optical encoders or resolvers etc. Adding sensors to detect rotor position affects the overall reliability and mechanical robustness of the system. Therefore, a whole new trend of replacing position sensors with sensorless rotor position estimation techniques have a promising demand.

Among the ...


Fully Decentralized Multi-Agent System For Optimal Microgrid Control, Ricardo de Azevedo 2016 Florida International University

Fully Decentralized Multi-Agent System For Optimal Microgrid Control, Ricardo De Azevedo

FIU Electronic Theses and Dissertations

In preparation for the influx of renewable energy sources that will be added to the electrical system, flexible and adaptable control schemes are necessary to accommodate the changing infrastructure. Microgrids have been gaining much attention as the main solution to the challenges of distributed and intermittent generation, but due to their low inertia, they need fast-acting control systems in order to maintain stability. Multi-Agent Systems have been proposed as dynamic control and communication frameworks. Decentralized arrangements of agents can provide resiliency and the much-desired “plug and play” behavior. This thesis describes a control system that implements droop control and the ...


Sparse Adaptive Local Machine Learning Algorithms For Sensing And Analytics, Jack Cannon 2016 Portland State University

Sparse Adaptive Local Machine Learning Algorithms For Sensing And Analytics, Jack Cannon

Undergraduate Research & Mentoring Program

The goal of digital image processing is to capture, transmit, and display images as efficiently as possible. Such tasks are computationally intensive because an image is digitally represented by large amounts of data. It is possible to render an image by reconstructing it with a subset of the most relevant data. One such procedure used to accomplish this task is commonly referred to as sparse coding. For our purpose, we use images of handwritten digits that are presented to an artificial neural network. The network implements Rozell's locally competitive algorithm (LCA) to generate a sparse code. This sparse code ...


Digital Commons powered by bepress