Controls and Control Theory Commons^™

Modeling, Simulation And Control Of Microrobots For The Microfactory., Zhong Yang

Electronic Theses and Dissertations

Future assembly technologies will involve higher levels of automation in order to satisfy increased microscale or nanoscale precision requirements. Traditionally, assembly using a top-down robotic approach has been well-studied and applied to the microelectronics and MEMS industries, but less so in nanotechnology. With the boom of nanotechnology since the 1990s, newly designed products with new materials, coatings, and nanoparticles are gradually entering everyone’s lives, while the industry has grown into a billion-dollar volume worldwide. Traditionally, nanotechnology products are assembled using bottom-up methods, such as self-assembly, rather than top-down robotic assembly. This is due to considerations of volume handling of large …

Live Access Control Policy Error Detection Through Hardware, Bryce Mendenhall

Graduate Theses and Dissertations

Access Control (AC) is a widely used security measure designed to protect resources and infrastructure in an information system. The integrity of the AC policy is crucial to the protection of the system. Errors within an AC policy may cause many vulnerabilities such as information leaks, information loss, and malicious activities. Thus, such errors must be detected and promptly fixed. However, current AC error detection models do not allow for real-time error detection, nor do they provide the source of errors. This thesis presents a live error detection model called LogicDetect which utilizes emulated Boolean digital logic circuits to provide …

Direct Torque Control For Silicon Carbide Motor Drives, Mohammad Hazzaz Mahmud

Graduate Theses and Dissertations

Direct torque control (DTC) is an extensively used control method for motor drives due to its unique advantages, e.g., the fast dynamic response and the robustness against motor parameters variations, uncertainties, and external disturbances. Using higher switching frequency is generally required by DTC to reduce the torque ripples and decrease stator current total harmonic distortion (THD), which however can lower the drive efficiency. Through the use of the emerging silicon carbide (SiC) devices, which have lower switching losses compared to their silicon counterparts, it is feasible to achieve high efficiency and low torque ripple simultaneously for DTC drives.

To overcome …

Adaptive Control And Parameter-Dependent Anti-Windup Compensation For Inertia Varying Quadcopters., Benjamin Edwards Farber

Electronic Theses and Dissertations

A novel parameter-dependent anti-windup compensator is developed to improve the performance of a saturation constrained model reference adaptive controller. The combined control structure solves the input saturation and stability problem for inertia varying quadcopters. The control synthesis follows the conventional two-step anti-windup design paradigm where a nominal controller is designed without consideration of the input saturation, and the anti-windup compensator is designed to minimize deviations from nominal performance caused by saturated inputs. To account for varying inertia of the quadcopter during package retrieval/delivery routines, the inertia parameters of the vehicle/package are estimated with an online recursive system identification technique, and …

Analysis Of Three-Phase Rectifier Via Three Different Control Methods And Switch Power Loss Comparison, Yichao Wang

All Graduate Theses, Dissertations, and Other Capstone Projects

Traditional uncontrolled or phase-controlled rectifiers have the defects of lower power factor and nontrivial higher harmonics which causes the low efficiency of power, bad power quality, and so on. However, PWM rectifiers overcome the drawbacks mentioned above. They reduce the higher harmonics yielding better sinusoidal current on the grid side, achieve unity power factor and bidirectional power flow, and have better dynamic performance. So, it is favored more by academia and widely applied in high-performance power electronics devices. In this paper, the PWM rectifier is analyzed and a comparison of the switch loss on three-phase rectifier using three different control …

An Analytic Study Of Pursuit Strategies, Mark E. Vlassakis

Theses and Dissertations

The Two-on-One pursuit-evasion differential game is revisited where the holonomic players have equal speed, and the two pursuers are endowed with a circular capture range ℓ > 0. Then, the case where the pursuers' capture ranges are unequal, ℓ₁ > ℓ₂ ≥ 0, is analyzed. In both cases, the state space region where capture is guaranteed is delineated and the optimal feedback strategies are synthesized. Next, pure pursuit is considered whereupon the terminal separation between a pursuer and an equal-speed evader less than the pursuer's capture range ℓ > 0. The case with two pursuers employing pure pursuit is considered, and …

A Comparative Analysis Of Reinforcement Learning Applied To Task-Space Reaching With A Robotic Manipulator With And Without Gravity Compensation, Jonathan Fugal

Theses and Dissertations--Electrical and Computer Engineering

Advances in computing power in recent years have facilitated developments in autonomous robotic systems. These robotic systems can be used in prosthetic limbs, wearhouse packaging and sorting, assembly line production, as well as many other applications. Designing these autonomous systems typically requires robotic system and world models (for classical control based strategies) or time consuming and computationally expensive training (for learning based strategies). Often these requirements are difficult to fulfill. There are ways to combine classical control and learning based strategies that can mitigate both requirements. One of these ways is to use a gravity compensated torque control with reinforcement …

Vision-Based Autonomous Tracking Of A Non-Cooperative Mobile Robot By A Low-Cost Quadrotor Vehicle, Cheikhna Ahmed Tidiane Sy

Electrical and Computer Engineering ETDs

The goal of this thesis is the detection and tracking of a ground vehicle, in particular a car-like robot, by a quadrotor. The first challenge to address in any pursuit or tracking scenario is the detection and unique identification of the target. From this first challenge, comes the need to precisely localize the target in a coordinate system that is common to the tracking and tracked vehicles. In most real-life scenarios, the tracked vehicle does not directly communicate information such as its position to the tracking one. From this fact, arises a non-cooperative constraint problem. The autonomous tracking aspect of …

An Application Of Sliding Mode Control To Model-Based Reinforcement Learning, Aaron Thomas Parisi

Master's Theses

The state-of-art model-free reinforcement learning algorithms can generate admissible controls for complicated systems with no prior knowledge of the system dynamics, so long as sufficient (oftentimes millions) of samples are available from the environ- ment. On the other hand, model-based reinforcement learning approaches seek to leverage known optimal or robust control to reinforcement learning tasks by mod- elling the system dynamics and applying well established control algorithms to the system model. Sliding-mode controllers are robust to system disturbance and modelling errors, and have been widely used for high-order nonlinear system control. This thesis studies the application of sliding mode control …

Underwater Remotely Operated Vehicle Controller With Pid Stability Regulation, Christian E. Aguirre

Electrical Engineering

The earth’s oceans and rivers remain widely unexplored. Hobbyists and companies across the globe invest money and resources into remotely operated vehicles (ROV) to further expand underwater knowledge. Each ROV includes a controller that operates motors and monitors other crucial system vitals. The ROV Controller project makes the process of designing an ROV simpler and more affordable by providing a multi-purpose programmable controller.

The ROV controller features programmable digital inputs/outputs and analog inputs. The controller processes control signals from analog joysticks, digital signals from a gyroscope and utilizes a MUX to expand the analog input capabilities of the Arduino. The …

Desarrollo De Una Estrategia De Control Predictivo Aplicado A Un Péndulo Invertido, Que Permita La Estabilización De Imágenes En Robots Para Exploración Agrícola, David Mateo Rojas Vallejo

Ingeniería en Automatización

La robótica es un campo de estudio tan amplio, que se puede extender prácticamente a cualquiera de las labores humanas; una de estas actividades es la agricultura, aunque para que esto se logre, primero se deben considerar factores mas específicos de un sistema robótico como: visión artificial, estructuras robóticas, control de sistemas, entre otros. En este proyecto se desarrolla una estrategia de control para una plataforma de péndulo invertido, que emula el sistema mecánico en donde se posicionaría la cámara de un robot agrícola. El sistema consiste en un péndulo invertido rotativo, y la estrategia de control que se implementó …

Ball Oscillating Bouncer, Eric Blok, Daniel Altemese, Ryan Nowacki, Maram Qurban

Williams Honors College, Honors Research Projects

The purpose of this report is to document the need, objectives, marketing and engineering requirements, as well as validate the design of an autonomous control device capable of continuously bouncing a table tennis ball on a paddle. This includes the design of a self correcting system using lightweight materials, and as few sensors and components as possible to achieve a compact, portable design. To accomplish this, the system is designed to react to a ball falling from as short a distance as 10 centimeters above the paddle, meaning all sensor processing, control processing, and motor drives should be able to …

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 Water Pump …

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 …

Interpreting, Stephanie Jo Kent

Doctoral Dissertations

What do community interpreting for the Deaf in western societies, conference interpreting for the European Parliament, and language brokering in international management have in common? Academic research and professional training have historically emphasized the linguistic and cognitive challenges of interpreting, neglecting or ignoring the social aspects that structure communication. All forms of interpreting are inherently social; they involve relationships among at least three people and two languages. The contexts explored here, American Sign Language/English interpreting and spoken language interpreting within the European Parliament, show that simultaneous interpreting involves attitudes, norms and values about intercultural communication that overemphasize information and discount …

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 …

Optimal Control Of Energy Efficient Buildings, Cale David Nelson

Masters Theses

The building sector consumes a large part of the energy used in the United States and is responsible for nearly 40% of greenhouse gas emissions. Therefore, it is economically and environmentally important to reduce the building energy consumption to realize massive energy savings. Commercial buildings are complex, multi-physics, and highly stochastic dynamic systems. Recent work has focused on integrating modern modeling, simulation, and control techniques to solving this challenging problem. The overall focus of this thesis is directed toward designing an energy efficient building by controlling room temperature. One approach is based on a distributed parameter model represented by a …

Development Of An Optical Sensor For Real-Time Weed Detection Using Laser Based Spectroscopy, Arie Jacobus Paap

Theses: Doctorates and Masters

The management of weeds in agriculture is a time consuming and expensive activity, including in Australia where the predominant strategy is blanket spraying of herbicides. This approach wastes herbicide by applying it in areas where there are no weeds. Discrimination of different plant species can be performed based on the spectral reflectance of the leaves. This thesis describes the development of a sensor for automatic spot spraying of weeds within crop rows. The sensor records the relative intensity of reflected light in three narrow wavebands using lasers as an illumination source.

A prototype weed sensor which had been previously developed …

The Modeling, Analysis And Control Of Resilient Manufacturing Enterprises, Yao Hu

Theses and Dissertations--Electrical and Computer Engineering

The resilience of manufacturing enterprises is an important research topic, since disruptions have severe effects on the normal operation of manufacturing enterprises, especially as manufacturing supply chains become global. Although many case studies have been carried out to address resilience in organizations, a systematic method to model and analyze the resilience dynamics in manufacturing enterprises is not well developed. This study is intended to conduct research on quantitative analysis and control for resilience.

After reviewing the literature addressing resilience, a modeling framework is presented to characterize the resilience of a manufacturing enterprise responding to disruptive events, which includes inventory ow …

Independent Moisture-Sensitive Automatic Watering System, Jessica Sherbon

Electrical Engineering

With the availability of home improvement supplies, plant owners can quickly and easily set up an automatic system that waters their gardens based on a specified schedule. However, most of these systems require an electric outlet or water faucet making them unusable in locations where installed water and power lines do not exist, such as apartment balconies. This project defines a small-scale automated watering system that runs independently of installed water and power lines. The system takes water from a reservoir, such as a tank or bucket, and supplies that water to individual plants via a drip system. The design …

Polar Field Oriented Control With 3rd Harmonic Injection, Martin Todd Hess

Master's Theses

Abstract

POLAR FIELD-ORIENTED CONTROL

with

3^RD HARMONIC INJECTION

Martin Todd Hess

Field Oriented Control (FOC), also known as vector control, is a widely used and well documented method for controlling Permanent-Magnet Synchronous Motors (PMSM) and induction motors. Almost invariably the orientation of the stator and rotor (field) fluxes are described in rectangular coordinates. In this thesis we explore the practicality of using polar coordinates.

Third harmonic injection is also a well-known technique that allows full utilization of the bus (DC-link), thus allowing the motor to run to full base speed without the use of field weakening. This technique potentially …

Attitude Estimation And Control Of Vtol Uavs, Andrew D. Roberts

Electronic Thesis and Dissertation Repository

The theoretical challenge involved in the operation of VTOL UAVs is often divided into two main problems. The first problem involves the development of an estimation scheme which can accurately recover the orientation, or angular position, of the aircraft. The second problem involves the development of algorithms which can be used to reliably control the orientation and/or the position of the vehicle. These two problems are the primary focus of this thesis.

We first consider the problem of attitude estimation. To solve this problem we use vector measurements, and in many cases, a gyroscope (to measure the angular velocity of …