Controls and Control Theory Commons^™

Identification Of Hydrodynamic Forces Developed By Flapping Fins In A Watercraft Propulsion Flow Field, Erdem Aktosun

University of New Orleans Theses and Dissertations

In this work, the data analysis of oscillating flapping fins is conducted for mathematical model. Data points of heave and surge force obtained by the CFD (Computational Fluid Dynamics) for different geometrical kinds of flapping fins. The fin undergoes a combination of vertical and angular oscillatory motion, while travelling at constant forward speed. The surge thrust and heave lift are generated by the combined motion of the flapping fins, especially due to the carrier vehicle’s heave and pitch motion will be investigated to acquire system identification with CFD data available while the fin pitching motion is selected as a function …

Design Of A New Electromagnetic Valve With A Hybrid Pm/Em Actuator In Si Engines, Ly Vinh Dat, Yaojung Shiao

Journal of Marine Science and Technology

Numerous devices have been developed for controlling valve timings in SI engines. Among them, the electromagnetic valve train (EMV) actuator can fully control valve timings to improve fuel consumption and emission. In addition, an EMV with a permanent-magnet and electromagnetic-coil (PM/EM) hybrid actuator has several advantages of control, energy consumption, and time response compared over conventional EMVs. This paper proposes a novel EMV with a PM/EM hybrid actuator that differs considerably from existing EMVs. Finite element analysis was used for analyzing the EMV design. The optimization was based on criteria that ensured the EMV to satisfy holding forces in closed …

Effective Orifice Area Of A Newly Developed Polyurethane Aortic Valve: Manufacturing And Evaluation, Wu-Chiao Shih, Ha-Hai Vu, Cheung-Hwa Hsu, Kai-Wen Yang, Yaw-Hong Kang

Journal of Marine Science and Technology

An optimal design for a polyurethane (PU) aortic valve was developed in a previous study. The current study investigated an approach for manufacturing PU aortic valves, evaluating the effective orifice areas (EOAs) of the prototypes. Two manufacturing approaches, assembly and single-piece forming methods, were developed. In the assembly method, support frames and valve leaflets were manufactured separately and then glued together by using an adhesive substance. By contrast, in the single-piece forming method, two main components of the valve were fabricated simultaneously by using a molding technique. This study established an experimental loop that mimics natural circulation from the left …

Modeling And Control Of A Novel Ball Screw Mechanism, Wen-Hsiang Hsieh, Kai-Bi Chang

Journal of Marine Science and Technology

This study proposes a systematic approach for the design and control of a novel ball screw transmission system. We investigated the structure of the system, performed kinematic analysis, and conducted dimensional synthesis by optimization. The mathematical model of the system was determined by system identification and a refined PID controller was designed. Computer simulation was conducted to verify the feasibility of the proposed design. A prototype machine and an experimental setup were built and tested. The experimental results show that the output with the controller agrees well with the required output. Therefore, the proposed design can produce the expected output …

Contour Data Acquisition System For Electric Vehicle Distance Estimation System, Kuew Wai Chew, Chee Ken Leong

Journal of Marine Science and Technology

The conventional distance estimation system only uses a constant speed and a constant level of road elevation to estimate the driving range of a vehicle. This technique leads to low prediction accuracy. In this project, a new estimation technique namely the Contour Positioning System (CPS) for an electric vehicle is proposed. The CPS provides a more reliable estimation of the electric vehicle battery energy usage by taking into consideration additional factors such as road elevation and regenerative braking energy. In order to perform the CPS calculation, first and foremost, the elevation profile of the selected destination must be determined. In …

Applying Fuzzy Logic Controller To Intelligent Solar Panel Cleaning System, Cong-Hui Huang

Journal of Marine Science and Technology

This paper presents an intelligent solar panel cleaning system that utilizes a fuzzy logic controller. The output voltage of the solar panel is applied to calculate whether to activate the cleaning mechanism. The direction and position of the system is set using a light sensor that is parallel to the direction of the sunlight. The data from the light sensors, combined with fuzzy logic control software developed using LabVIEW, determine the control commands (stop, forward, and reverse) for the stepper motors controlling the cleaning process. The cleaning process, which is repeated until the power output from the solar panels is …

Discoid And Asymmetrical Gyroless Micro-Satellite Off-Modulation Attitude Control With Kalman Filter, Ho-Nien Shou

Journal of Marine Science and Technology

The gyroless attitude control method and kalman algorithm procedures presented in this paper are applicable to asymmetrical microsatellites of any shape with large mass variation and without angular rate sensors. The attitude sensors include a three-axis magnetometer, a horizon sensor, and a coarse sun sensor (CSS), which together serve as an analytic platform and help in ensuring the stability of attitude controls. The attitude control problem of microsatellites has become a focal point because microsatellite fabrication processes are short, costless, and can be flexibly used for various purposes. The center of mass of the microsatellite can be offset because of …

Periodic Damage Evaluation Of Aging Offshore Jackets Based On Continuous Dynamic Tests, Fu-Shun Liu, Hong-Chao Lu, Wei-Ying Wang, Dong-Ping Yang

Journal of Marine Science and Technology

This study proposes a new method for evaluating the damage of aging offshore platforms, based on dynamic tests. The proposed method involves a new damage indicator for reducing the effects of occurred damages accumulated before the first measurement. One theoretical improvement is that the requirement of using the stiffness matrix of the finite element model to replace that of the measured model can be ignored in calculating the modal strain energy of the measured model. The other development is that the proposed approach can be used for providing reasonable evaluations of damages that occurred between two adjacent dynamic tests. This …

Fault Diagnosis And Performance Assessment For A Rotary Actuator Based On Neural Network Observer, Jian Ma, Xin Li, Chen Lu, Zi-Li Wang

Journal of Marine Science and Technology

Substantial damage may occur when a rotary actuator fails during operation. Therefore, effective fault diagnosis of a rotary actuator is crucial to ensuring the safety of the device. However, only a few studies on fault detection, fault isolation, and performance assessment have focused on rotary actuators. In this study, fault detection and fault isolation processes were implemented by designing two observers based on a neural network, and a method that assesses the performance of the rotary actuator is proposed. First, two observers are established according to the structure of the rotary actuator. Data in their normal state are used to …

Preface, Wen-Hsiang Hsieh

Journal of Marine Science and Technology

No abstract provided.

Research On Sealing Performance Of Hydrostatic Pressure Mechanical Seal, Wei-Bing Zhu, He-Shun Wang, Sheng-Ren Zhou

Journal of Marine Science and Technology

The hydrostatic pressure mechanical seal has many advantages, and it can be used in rotating machines with lower speed. Based on the externally pressurized stable gas lubrication theory, the control equation of end face flow field for hydrostatic pressure mechanical seal with orifice compensation was established. The functional extremum algorithm and the finite element method were used to solve this equation. The effects of gas film thickness, air supply pressure, throttle orifice number and diameter, on face opening force and gas film stiffness were discussed in detail. The results show that the opening force decreases with the widening of face …

Performance Evaluation Of Three Types Of Passive Micromixer With Convergent-Divergent Sinusoidal Walls, Arshad Afzal, Kwang-Yong Kim

Journal of Marine Science and Technology

A passive split-and-recombination micromixer with convergent-divergent channel walls of sinusoidal variation has been investigated using numerical simulations. With water and ethanol as working fluids, the analysis was performed using Navier-Stokes equations with convection-diffusion model in a Reynolds number range, 10  Re  70. Performances of three configurations with different split-and-recombination arrangements were evaluated in terms of mixing index and pressure drop. A parametric study was also conducted with two geometrical parameters, i.e., the ratios of throat-width to diameter of circular wall and diameter of circular wall to amplitude. The results showed a significant dependence of the mixing performance on …

Synthetic Physical Models For Animating Unsteady Fish Motions, Shyh-Kuang Ueng, Hong-Kai Chen

Journal of Marine Science and Technology

This paper presents physical models for simulating unsteady fish motions, including bursting, gliding, braking, turning, ascending and descending. A new wave model, the controllable body wave model, is developed to undulate the fish body to produce bursting and gliding motions. A key frame approach is adopted to realize braking, turning, descending and ascending. In the key frame method, individual motions are decomposed into sequences of key steps. The gestures of the fish in these key steps are recorded and regarded as key frames. In the run time, these recorded key frames are sequentially reproduced to generate swimming patterns. In addition …

Development Of An Intelligent Energy Saving Heat Pump For Water Heater With Fuzzy Logic Controller, Cong-Hui Huang

Journal of Marine Science and Technology

There is a growing awareness of the importance of using clean and environmentally friendly sources of energy. This paper presents the development of an intelligent energy saving heat pump for a water heater with a fuzzy logic controller that analyzes the heating efficiency of the heat pump heater. The fuzzy logic controller is employed for developing a heating algorithm to raise the efficiency of the heat pump heater and suppress unnecessary heating at high temperatures. Experimental results show that our heat pump heater produces an energy saving of 60% of total energy input, compared to the 23% for a gas …

A Study On Optimization Of Ship Hull Form Based On Neuro-Response Surface Method (Nrsm), Soon-Sub Lee, Jae-Chul Lee, Sung-Chul Shin, Soo-Young Kim, Hyun-Sik Yoon

Journal of Marine Science and Technology

Building large and eco-friendly ships has become a clear trend in the ship building industry. Research to minimize ship resistance has actively been investigated for energy savings and environmental protection. However, optimization of the full geometry, while taking into account the hydrodynamic performance is difficult because extensive time is needed to calculate the performance factors, such as the resistance and propulsion. Hence we suggest an optimal design framework based on the neuro-response surface method (NRSM) for optimal shape design in consideration of hydrodynamic performance. The optimization algorithm of the constructed framework consists of the back-propagation neural network (BPN) and the …

Design Of A Haptic Interface For Medical Applications Using Magneto-Rheological Fluid Based Actuators, Nima Najmaei

Electronic Thesis and Dissertation Repository

This thesis reports on the design, construction, and evaluation of a prototype two degrees-of-freedom (DOF) haptic interface, which takes advantage of Magneto-Rheological Fluid (MRF) based clutches for actuation. Haptic information provides important cues in teleoperated systems and enables the user to feel the interaction with a remote or virtual environment during teleoperation. The two main objectives in designing a haptic interface are stability and transparency. Indeed, deficiencies in these factors in haptics-enabled telerobotic systems has the introduction of haptics in medical environments where safety and reliability are prime considerations. An actuator with poor dynamics, high inertia, large size, and heavy …

Design Of System Level Control For A Residential Power Router, Fahad Hossain

Graduate Theses and Dissertations

This thesis presents the overall power flow and load management system for a 2 kW residential power router. The objective is to satisfy the residential load demand with cost savings by managing the energy sources including PV, battery, generator, and grid. The power flow management system algorithm is developed both for grid-connected mode and island mode. This algorithm involves the battery state of charge estimation, available PV power, load demand and electricity grid pricing. The residential load management algorithm is also developed using PV power prediction and load power prediction acquired for a day.¬ A Labview GUI is also developed …

Development Of A Digital Controller For Motor Control Experiments In The Ee472 Lab, Jeffrey David D'Amelio

Master's Theses

A digital motor controller for student lab use is designed, built, and tested. The controller uses an encoder for position measurement, and an H-bridge to drive the electromechanical plant.

A user interface is created to enhance usability of the device. The user interface is able to display key parameters of the control algorithm as well as the state of the system. It is also used to modify the gains and sample rate of the control algorithm.

The design of the system is refined, and 10 units are built for the EE472 Digital Controls Lab. The lab manuals for the first …

A Dc Distribution System For Power System Integration Of Plug-In Electric Vehicles; Modeling, Stability And Operation, Mansour Tabari

Electronic Thesis and Dissertation Repository

This thesis is mainly focused on (i) modeling of dc distribution systems for power system integration of plug-in electric vehicles (PEVs), (ii) proposing a method to enhance the stability of the dc distribution systems, and (iii) proposing an energy management strategy to control the power flow in the dc distribution system. The dc distribution system is expected to be more efficient and economical than a system of ac-dc battery chargers directly interfaced with an ac grid.

In the first part, a systematic method for developing a model for a dc distribution system, based on the configuration of the system is …

A 12-Sector Space Vector Switching Scheme For Performance Improvement Of Matrix Converter Based Dtc Of Im Drive, Saad Mekhilef, Sina Sebtahmadi

Saad Mekhilef

No abstract provided.

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 …

Comprehensive Statcom Control For Distribution And Transmission System Applications, Shubham Gupta

Electronic Thesis and Dissertation Repository

This thesis presents the development of a comprehensive STATCOM controller for load compensation, voltage regulation and voltage balancing in electric power distribution and transmission networks. The behavior of this controller is first validated with published results. Subsequently, the performance of this STATCOM controller is examined in a realistic Hydro One distribution feeder for accomplishing the compensation of both mildly and grossly unbalanced loads, and balancing of network voltages using PSCAD/EMTDC software. The STATCOM voltage control function is utilized for increasing the connectivity of wind plants in the same distribution feeder. The thesis further presents a frequency scanning technique for simple …

Added Mass Computation For Control Of An Open-Frame Remotely-Operated Vehicle: Application Using Wamit And Matlab, You-Hong Eng, Cheng-Siong Chin, Michael Wai-Shing Lau

Journal of Marine Science and Technology

In this paper, numerical modeling and testing of a complexshaped remotely-operated vehicle (ROV) are shown. The paper emphasizes on systematic modeling of hydrodynamic added mass using computational fluid dynamic software WAMITTM on the open frame ROV that is not commonly applied in practice. From initial design and prototype testing, a small-scale test using a free-decaying experiment is used to verify the theoretical models obtained from WAMITTM. Simulation results have shown to coincide with the experimental tests. The proposed method is able to determine the hydrodynamic added mass coefficients of the open frame ROV.

Design And Implementation Of A Byzantine Fault Tolerance Framework For Non-Deterministic Applications, H. Zhang, Wenbing Zhao, Louise E. Moser, P. Michael Melliar-Smith

Wenbing Zhao

State-machine-based replication is an effective way to increase the availability and dependability of mission-critical applications. However, all practical applications contain some degree of non-determinism. Consequently, ensuring strong replica consistency in the presence of application non-determinism has been one of the biggest challenges in building dependable distributed systems. In this Study, the authors propose a classification of common types of application non-determinism with respect to the requirement of achieving Byzantine fault tolerance (BFT), and present the design and implementation of a BFT framework that controls these types of non-determinism in a systematic manner.

A Prototype Microwave Cavity Control Circuit For Use In Next Generation Free Electron Laser, Josh Thompson, Peter Neal Barrina, Jiayi Jiang, Joe Frisch, Steve Smith, Daniel Van Winkle

STAR Program Research Presentations

One of the current programs at SLAC National Accelerator Laboratory is the Linac Coherent Light Source, or LCLS. Using the existing hardware of the last third of their linear accelerator (or “linac”), SLAC has created one of the most energetic X-ray free electron lasers (or “FEL”). Since 2009, LCLS has used this FEL to perform a wide range of experiments across all sciences, most notably ultrafast filming at the molecular scale. As requests for beam-time with this laser increases, SLAC is purposing a linac upgrade to better match this demand. This upgrade, named LCLS-II, will replace existing copper radio frequency …

A Cfd Assisted Control System Design For Supercritical Water Cooled Reactor, Rohit V. Maitri

Electronic Thesis and Dissertation Repository

In this study, the methodology to construct a control system based on computational fluid dynamics (CFD) simulations is developed for supercritical water cooled reactor (SCWR). The CFD model using Reynolds Stress Model (RSM) and k-w SST model is validated with the experimental cases of steady state and vertically up flowing supercritical water in circular tubes for normal heat transfer and deteriorated heat transfer (DHT) cases. This model is extended to simulate the transient thermal-hydraulic behaviour of supercritical fluid flow and heat transfer, and the results are also compared with the 1-D numerical model, THRUST. The DHT phenomenon is investigated using …

Combined Traction And Energy Recovery Motor For Electric Vehicles, James Long, Xin Wang, Claude Kansaku, Brian Moravec

TREC Final Reports

Electric vehicle manufacturers are looking for ways to optimize energy use for vehicle range extension and reduction of battery capacity. Electric motors have lower efficiencies at very low speed and high torque. This is typically at vehicle launch from standstill, at very low speeds, and during energy regeneration at lower speeds and approaching standstill. The KersTech solution is a breakthrough technology allowing supplement of the electric drive with a hydraulic drive, active in lower speeds ranges, dropping out as the electric motor takes over in its higher efficiency range of operation. The report consists of four parts. Part I presents …

Feedback Control For Multi-Modal Optimization Using Genetic Algorithms, Jun Shi, Ole J. Mengshoel, Dipan K. Pal

Ole J Mengshoel

Application Of Adaptive Variable Speed Back-Stepping Sliding Mode Controller For Pmlsm Position Control, Mei-Yung Chen, Jian-Shiun Lu

Journal of Marine Science and Technology

In this research, an adaptive variable speed back-stepping sliding mode controller (AVSBSMC) is proposed to control the permanent magnet linear synchronous motor (PMLSM) on high-precision positioning servo system platform. This controller combines the dynamic features of variable speed control (VSC) and the positioning characteristics of adaptive back-stepping sliding mode control (ABSMC). Firstly, the detailed dynamic machine model of PMLSM is established. Secondly, the proportional-integral-derivative (PID) and ABSMC controllers are proposed to compensate the uncertainties in position control. Then, the one provides the better servo performances is the position controller in the motor system. Thirdly, the variable speed controller (VSC) and …