Acoustics, Dynamics, and Controls Commons^™

Stability Analysis Of Thermohaline Convection With A Time-Varying Shear Flow Using The Lyapunov Method, Kalin Kochnev

Honors Scholar Theses

This work applies the Lyapunov method to identify instabilities and compute the growth rate of a linear time-varying system. The linear system studied describes cold fresh water on top of hot salty water with a periodically time-varying background shear flow. A time-dependent weighting matrix is employed to construct a Lyapunov function candidate. The resulting linear matrix inequalities are discretized in time using the forward Euler method. As the number of temporal discretization points increases, the growth rate predicted by the Lyapunov method or Floquet theory, used for comparison, will converge to the same value obtained from numerical simulations. Furthermore, the …

Cloudbots: Autonomous Atmospheric Explorers, Akash Binoj

Honors Scholar Theses

The CloudBot is an autonomous weather balloon that operates on the principle of variable buoyancy to ascend and descend in the atmosphere. This project aims to develop a device that will collect atmospheric measurements and communicate them mid-flight. The apparatus consists of a helium-filled balloon, the robotic payload, and an air cell. The fixed-volume helium balloon at the top provides an upwards buoyancy force, while the air cell at the bottom can hold a variable amount of pressure to adjust the weight of the CloudBot. By doing so, it is able to travel in storm conditions and collect valuable atmospheric …

Design Of Versatile Feedback Control System Components For Selective Laser Sintering, Thomas Chessman

University Scholar Projects

Selective laser sintering (SLS) is an additive manufacturing technique that involves using a laser to fuse powdered material together, layer by layer, in order to create a 3-D product. Despite its numerous benefits over traditional methods of manufacturing, including higher efficiency, versatility, and the ability to process many materials, selective laser sintering suffers from its propensity to generate structural errors during operation.

Feedback control has been shown to improve fabrication quality in other laser-based additive manufacturing techniques when implemented properly. Widespread exploration of applying feedback control in SLS might lead to significant performance improvements in this form of manufacturing.

This …

Efficient Characterization Of Structural Dynamic Responses Under Uncertainties: From Order-Reduced Simulation To Data-Driven Emulation, Zeping Xia

Master's Theses

The efficiency of sampling remains as one of the major challenges for uncertainty analysis in structural dynamics. In the context of numerical experiments, this difficulty primarily lies in the fact that every single run of a numerical model, which usually is of large scale in modern engineering practice, would be expensive in terms of CPU times and memories. Nonetheless, understanding and predicting dynamic characteristics of structural systems with uncertainties is important for structural design, assessment and control. In order to develop fast and economical sampling techniques for characterizing structural dynamics, we explored two categories of methods from two opposite direction: …

Dynamic Test Scheduling In Hardware-In-The-Loop Simulation Of Commercial Vehicles, Tenil Cletus

Master's Theses

Modern day commercial vehicles are controlled by various Electronic Control Units (ECU). They are not only tested as single units, but also by networking them in Controlled Area Network bus (CAN) to form a complete electrical control system. This is achieved using Hardware In the Loop (HIL) Integration Lab. In HIL, the electrical system is connected to a real time mathematical model of the vehicle plus it’s environment so as to form a loop.

Testing functionality of the electrical system begins by defining functional tests. An example would be testing cruise control activation. Executing each test is made possible by …

Applied Control Strategies At A Cogeneration Plant, Joseph William Burns

Master's Theses

The purpose of this paper is to demonstrate the effectiveness of “classical strategies for dynamic control” on authentic cogeneration processes. These strategies are applied to several processes at the University of Connecticut’s cogeneration plant. Case studies of their applications are presented in this paper. Strategies that are applied include the following:

1) The classical SISO feedback structure

2) The First Order Plus Dead Time (FOPDT) process model

3) The Internal Model Control (IMC) correlations for PI controller tuning

4) Static feed forward with feedback trim

5) Cascade Control

Robust Region Tracking In Multi-Agent Systems Utilizing Sliding Mode Control: Theory And Applications, Mark Bacon

Master's Theses

This thesis presents a methodology to bring controlled agents within a moving region despite agent interaction dynamics, uncertain forces and parameter variation. The logic is derived from traditional Sliding Mode Control theory with an expanded boundary layer which allows position deviation from the region center to specified bounds. As an example of the utility of this control, multiple methods of herding (controlling passive agents by appropriate positioning of controlled agents) are presented.