Engineering Commons^™

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 …

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 …

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 …

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 …

Design And Development Of Magneto-Rheological Actuators With Application In Mobile Robotics, Wenjun Li

Electronic Thesis and Dissertation Repository

In recent years, Magneto-Rheological (MR) fluids devices are widely studied and used for various purposes. Among these MR fluids devices, the MR actuator has attracted increasing attention for last two decades. An MR actuator is usually made of an active component (motor) and MR clutches. Compared with the regular actuators, the MR actuator features compliance due to the existence of MR fluids, which is commonly consider as benefits at the aspect of safety. On the other hand, the MR actuator has advantages on controllable bandwidth, torque-mass and torque-inertia ratios compared with the other compliant actuators.

In this study, a new …

Modeling And Control Of Steerable Ablation Catheters, Mahta Khoshnam Tehrani

Electronic Thesis and Dissertation Repository

Catheters are long, flexible tubes that are extensively used in vascular and cardiac interventions, e.g., cardiac ablation, coronary angiography and mitral valve annuloplasty. Catheter-based cardiac ablation is a well-accepted treatment for atrial fibrillation, a common type of cardiac arrhythmia. During this procedure, a steerable ablation catheter is guided through the vasculature to the left atrium to correct the signal pathways inside the heart and restore normal heart rhythm. The outcome of the ablation procedure depends mainly on the correct positioning of the catheter tip at the target location inside the heart and also on maintaining a consistent contact between the …

Control Of Cooperative Haptics-Enabled Teleoperation Systems With Application To Minimally Invasive Surgery, Amir Takhmar

Electronic Thesis and Dissertation Repository

Robot-Assisted Minimally Invasive Surgical (RAMIS) systems frequently have a structure of cooperative teleoperator systems where multiple master-slave pairs are used to collaboratively execute a task. Although multiple studies indicate that haptic feedback improves the realism of tool-tissue interaction to the surgeon and leads to better performance for surgical procedures, current telesurgical systems typically do not provide force feedback, mainly because of the inherent stability issues. The research presented in this thesis is directed towards the development of control algorithms for force reflecting cooperative surgical teleoperator systems with improved stability and transparency characteristics. In the case of cooperative force reflecting teleoperation …