Controls and Control Theory Commons^™

Motion Coordination Of Aerial Vehicles, Abdelkader Abdessameud

Electronic Thesis and Dissertation Repository

The coordinated motion control of multiple vehicles has emerged as a field of major interest in the control community. This thesis addresses two topics related to the control of a group of aerial vehicles: the output feedback attitude synchronization of rigid bodies and the formation control of Unmanned Aerial Vehicles (UAVs) capable of Vertical Take-Off and Landing (VTOL). The information flow between members of the team is assumed fixed and undirected. The first part of this thesis is devoted to the attitude synchronization of a group of spacecraft. In this context, we propose control schemes for the synchronization of a …

Fuzzy Logic Control Of An Inverted Pendulum Robot, Kyle Reid

Electrical Engineering

The inverted pendulum is a classical problem in controls. The inherit instabilities in the setup make it a natural target for a control system. Over the years it has been the benchmark for testing new and innovative control theories such as Fuzzy Logic. During the course of this project a software fuzzy logic controller was implemented using a PIC microcontroller. At the conclusion of the experiment an interesting realization was made about the nature of Fuzzy Logic and its applicability in the world of controls.

Adaptive Algorithms For Coverage Control And Space Partitioning In Mobile Robotic Networks, Jerome Le Ny, George J. Pappas

Technical Reports (ESE)

We consider deployment problems where a mobile robotic network must optimize its configuration in a distributed way in order to minimize a steady-state cost function that depends on the spatial distribution of certain probabilistic events of interest. Three classes of problems are discussed in detail: coverage control problems, spatial partitioning problems, and dynamic vehicle routing problems. Moreover, we assume that the event distribution is a priori unknown, and can only be progressively inferred from the observation of the location of the actual event occurrences. For each problem we present distributed stochastic gradient algorithms that optimize the performance objective. The stochastic …

Compensation Of Torque Ripple In High Performance Bldc Motor Drives, Ilhwan Kim, Nobuaki Nakazawa, Sungsoo Kim, Chanwon Park, Chansu Yu

Electrical Engineering & Computer Science Faculty Publications

Brushless DC motor drives (BLDC) are finding expanded use in high performance applications where torque smoothness is essential. The nature of the square-wave current excitation waveforms in BLDC motor drives permits some important system simplifications compared to sinusoidal permanent magnet AC (PMAC) machines. However, it is the simplicity of the BLDC motor drive that is responsible for causing an additional source of ripple torque commonly known as commutation torque to develop. In this paper, a compensation technique for reducing the commutation torque ripple is proposed. With the experimental results, the proposed method demonstrates the effectiveness for a control …

Sprawl Angle In Simplified Models Of Vertical Climbing: Implications For Robots And Roaches, Goran A. Lynch, Lawrence Rome, Daniel E. Koditschek

Departmental Papers (ESE)

Empirical data taken from fast climbing sprawled posture animals reveals the presence of strong lateral forces with significant pendulous swaying of the mass center trajectory in a manner captured by a recently proposed dynamical template. In this simulation study we explore the potential benefits of pendulous dynamical climbing in animals and in robots by examining the stability and power advantages of variously more and less sprawled limb morphologies when driven by conventional motors in contrast with animal-like muscles. For open loop models of gait generation inspired by the neural-deprived regimes of high stride-frequency animal climbing, our results corroborate earlier hypotheses …

Disturbance Detection, Identification, And Recovery By Gait Transition In Legged Robots, Aaron M. Johnson, Galen Clark Haynes, Daniel E. Koditschek

Departmental Papers (ESE)

We present a framework for detecting, identifying, and recovering within stride from faults and other leg contact disturbances encountered by a walking hexapedal robot. Detection is achieved by means of a software contactevent sensor with no additional sensing hardware beyond the commercial actuators’ standard shaft encoders. A simple finite state machine identifies disturbances as due either to an expected ground contact, a missing ground contact indicating leg fault, or an unexpected “wall” contact. Recovery proceeds as necessary by means of a recently developed topological gait transition coordinator. We demonstrate the efficacy of this system by presenting preliminary data arising from …

Wavelet Based Islanding Detection Of Dc-Ac Inverter Interfaced Dg Systems, Mohamed Moin Hanif, Malabika Basu, Kevin Gaughan

Conference papers

The increased penetration of distributed generation (DG) often connected to grid through dc-ac interface has made islanding detection an important and challenging issue to power engineers. Several methods based on passive and active detection scheme have been proposed in the literature. While passive schemes have a large non detection zone (NDZ), concern has been raised on active method due to its degrading power quality effect. This paper proposes a wavelet based passive islanding detection scheme with almost zero NDZ for dc-ac inverter interfaced grid connected DGs. The key idea is to utilize the spectral changes in the higher frequency components …

Stochastic Optimal Control In Nonlinear Systems, Celestin Nkundineza

Mechanical (and Materials) Engineering -- Dissertations, Theses, and Student Research

Stochastic control is an important area of research in engineering systems that undergo disturbances. Controlling individual states in such systems is critical. The present investigation is concerned with the application of the stochastic optimal control strategy developed by To (2010) and its implementation as well as providing computed results of linear and nonlinear systems under stationary and nonstationary random excitations. In the strategy the feedback matrix is designed based on the achievement of the objectives for individual states in the system through the application of the Lyapunov equation for the system. Each diagonal element in the gain or associated gain …

Conservation Based Uncertainty Propagation In Dynamic Systems, Lillian J. Ratliff

UNLV Theses, Dissertations, Professional Papers, and Capstones

Uncertainty is present in our everyday decision making process as well as our understanding of the structure of the universe. As a result an intense and mathematically rigorous study of how uncertainty propagates in the dynamic systems present in our lives is warranted and arguably necessary. In this thesis we examine existing methods for uncertainty propagation in dynamic systems and present the results of a literature survey that justifies the development of a conservation based method of uncertainty propagation. Conservation methods are physics based and physics drives our understanding of the physical world. Thus, it makes perfect sense to formulate …

Enhanced Cal Poly Super System Simulink Model, Matthew Ogden Mcfarland

Master's Theses

The Cal Poly Sustainable Power for Electrical Resources (SuPER) project is a solar power DC distribution system designed to autonomously manage and supply the energy needs of a single family off-the-grid home. The following thesis describes the improvement and re-design of a MATLAB Simulink model for the Cal Poly SuPER system. This model includes a photovoltaic (PV) array, a lead-acid gel battery with temperature effects, a wind turbine model, a re-designed DC-DC converter, a DC microgrid, and multiple loads. This thesis will also include several control algorithms such as a temperature controlled thermoelectric (T.E.) cooler, intelligent load switching, and an …

Classification And Identification Of Environment Through Dynamic Coupling, Haldun Komsuoglu

Departmental Papers (ESE)

This paper presents a methodology enabling robotic systems to classify and identify their environment according to the mechanical properties of the local contact dynamics. Described approach employs existing proprioceptive sensors and requires no additional specialized hardware. Identification process is performed in real-time with temporal resolution of measurement updates determined by the periodicity of the limit behavior. While the basic concept has a wide application spectrum, our discussion focuses on terrestrial locomotion where contact properties, such a compliance, damping, sheer friction and surface topology, are important environmental markers. Accurate identification of environmental parameters enables two types of applications. In behavioral control, …

A Comparison Of Induction Motor Starting Methods Being Powered By A Diesel-Generator Set, Adam John Wigington

Theses, Dissertations, and Student Research from Electrical & Computer Engineering

Starting induction motors on isolated or weak systems is a highly dynamic process that can cause motor and load damage as well as electrical network fluctuations. Mechanical damage is associated with the high starting current drawn by a ramping induction motor. In order to compensate the load increase, the voltage of the electrical system decreases. Different starting methods can be applied to the electrical system to reduce these and other starting method issues. The purpose of this thesis is to build accurate and usable simulation models that can aid the designer in making the choice of an appropriate motor starting …

Feedback Control Of The National Airspace System, Jerome Le Ny, Hamsa Balakrishnan

Technical Reports (ESE)

This paper proposes a general modeling framework adapted to the feedback control of traffic flows in Eulerian models of the National Airspace System (NAS). It is shown that the problems of scheduling and routing aircraft flows in the NAS can be posed as the control of a network of queues with load-dependent service rates. We can then focus on developing techniques to ensure that the aircraft queues in each airspace sector, which are an indicator of the air traffic controller workloads, are kept small. This paper uses the proposed framework to develop control laws that help prepare the NAS for …

Architectural Considerations For Single Operator Management Of Multiple Unmanned Aerial Vehicles, Gabriel T. Bugajski

Theses and Dissertations

Recently, small Unmanned Aircraft Systems (UAS) have become ubiquitous in military battlefield operations due to their intelligence collection capabilities. However, these unmanned systems consistently demonstrate limitations and shortfalls with respect to size, weight, range, line of sight and information management. The United States Air Force Unmanned Aircraft Systems Flight Plan 2009-2047 describes an action plan for improved UAS employment which calls out single operator, multi-vehicle mission configurations. This thesis analyzes the information architecture using future concepts of operations, such as biologically-inspired flocking mechanisms. The analysis and empirical results present insight into the engineering of single-operator multiple-vehicle architectures.

Solar Panel Tracker, Andrew Hsing

Electrical Engineering

This project will be a design and implementation of a polar single axis solar panel tracker. It will have a fixed vertical axis and an adjustable horizontal motor controlled axis. This setup is similar to an office swivel chair. The tracker will actively track the sun and change its position accordingly to maximize the energy output. To prevent wasting power by running the motor continuously, the tracker will correct it's position after 2 to 3 degrees of misalignment. The sensors will compare the light intensities of each side and move the panels until the tracker detects equal light on both …

Pulse Density Modulated Soft Switching Cycloconverter, Jesse Timothy Adamson

Master's Theses

Single stage cycloconverters generally incorporate hard switching at turn on and soft switching at turn off. This hard switching at turn on combined with the slow switching speeds of thyristors (the switch of choice for standard cycloconverters) limits their use to lower frequency applications.

This thesis explores the analysis and design of a pulse density modulated (PDM), soft switching cycloconverter. Unlike standard cycloconverters, the controller in this converter does not adjust thyristor firing angles. It lets only complete half cycles of the input waveform through to the output. This allows and requires a much greater frequency step down from the …

Multiple Robot Boundary Tracking With Phase And Workload Balancing, Michael Jay Boardman

Master's Theses

This thesis discusses the use of a cooperative multiple robot system as applied to distributed tracking and sampling of a boundary edge. Within this system the boundary edge is partitioned into subsegments, each allocated to a particular robot such that workload is balanced across the robots. Also, to minimize the time between sampling local areas of the boundary edge, it is desirable to minimize the difference between each robot’s progression (i.e. phase) along its allocated sub segment of the edge. The paper introduces a new distributed controller that handles both workload and phase balancing. Simulation results are used to illustrate …

Adverse Elevator Effect In Landing Flare, Nihad E. Daidzic

Aviation Department Publications

No abstract provided.

Determination Of Material Emission Signatures By Ptr-Ms And Their Correlations With Odor Assessments By Human Subjects, Kwanghoon Han

Kwanghoon Han

The objectives of this study were to determine volatile organic compound (VOC) emission signatures of nine typical building materials by using proton transfer reaction-mass spectrometry (PTR-MS) and to explore the correlation between the PTR-MS measurements and the measurements of acceptability by human subjects. VOC emissions from each material were measured in a 50-l small-scale chamber. Chamber air was sampled by PTR-MS to determine emission signatures. Sorbent tube sampling and TD-GC/MS analysis were also performed to identify the major VOCs emitted and to compare the resulting data with the PTR-MS emission signatures. The data on the acceptability of air quality assessed …

Embedded Virtual Machines For Robust Wireless Control And Actuation, Miroslav Pajic, Rahul Mangharam

Departmental Papers (ESE)

Embedded wireless networks have largely focused on open-loop sensing and monitoring. To address actuation in closed-loop wireless control systems there is a strong need to re-think the communication architectures and protocols for reliability, coordination and control. As the links, nodes and topology of wireless systems are inherently unreliable, such time-critical and safety-critical applications require programming abstractions and runtime systems where the tasks are assigned to the sensors, actuators and controllers as a single component rather than statically mapping a set of tasks to a specific physical node at design time. To this end, we introduce the Embedded Virtual Machine (EVM), …