Acoustics, Dynamics, and Controls Commons^™

Noise Reduction Techniques In Commercial Aircraft Cabins, Hashem Hashem

Student Works

Main sources of noise heard inside an aircraft cabin:

• Engines
• Airframe & control surfaces
• Window vibrations
• Passenger announcements & activities.

Design And Validation Of An Aerodynamic System For A Formula Sae® Vehicle Using Vehicle Dynamic Simulation And Experimentation, Evan S. Cole

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis presents the design, simulation, and experimental validation for the aerodynamic system for a Formula SAE® vehicle. The Society of Automotive Engineers ® (SAE) hosts a collegiate competition annually called Formula SAE® where students design, fabricate, and test a small “formula style” vehicle. The vehicle performs in relatively slow maneuvers, around different courses and tests to evaluate the vehicle’s overall performance. Over the years, collegiate teams have put significant research into the design and manufacturing of the aerodynamics of these vehicles. In order to justify this undertaking for future teams at West Virginia University’s Formula SAE® program, a comprehensive …

Optimal Path Planning For Aerial Robots Using Genetic Algorithm, Anna Puigvert I Juan

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis presents a path optimization solution for a robot in two different constrained 3-dimensional (3D) environments. The robot is required to travel from its current position to a goal position following minimum cost paths (optimal paths). The first environment has 3D obstacles that interfere with the robot’s path. The path cost for this environment accounts for the minimum distance traveled by the robot from the start to the goal position while avoiding obstacles. The second environment is the atmosphere of Venus, specifically a flyable region of this atmosphere with characteristics similar to Earth’s. This environment has strong westward winds …

Koopman Operator Theory And The Applied Perspective Of Modern Data-Driven Systems, Alex Krolicki

All Theses

Recent theoretical developments in dynamical systems and machine learning have allowed researchers to re-evaluate how dynamical systems are modeled and controlled. In this thesis, Koopman operator theory is used to model dynamical systems and obtain optimal control solutions for nonlinear systems using sampled system data. The Koopman operator is obtained using data generated from a real physical system or from an analytical model which describes the physical system under nominal conditions. One of the critical advantages of the Koopman operator is that the response of the nonlinear system can be obtained from an equivalent infinite dimensional linear system. This is …

Ultrasound Mediated Tissue Growth In Bioinspired Scaffolds, Marco Fielder

Graduate Theses and Dissertations

Porous scaffolds mechanically stimulated with ultrasound are used for the treatment of bone conditions such as osteoporosis or traumatic bone injury. However, one current issue in these treatment techniques is designing a scaffold structure with a high structural integrity that also does not impede tissue growth. A larger ultrasound wave transmission would also allow more of a scaffold to receive mechanical stimulation from ultrasound. Controlling mesenchymal stem cell seeding of tissue scaffolds also has potential for developing optimal seeding patterns to maximize or control tissue growth in the scaffold based on an individual’s physiology. There is also a need for …

Multiple Objective Function Optimization And Trade Space Analysis, Yifan Xu

All Theses

Optimization can assist in obtaining the best possible solution to a design problem by varying related variables under given constraints. It can be applied in many practical applications, including engineering, during the design process. The design time can be further reduced by the application of automated optimization methods. Since the required resource and desired benefit can be translated to a function of variables, optimization can be viewed as the process of finding the variable values to reach the function maxima or minima. A Multiple Objective Optimization (MOO) problem is when there is more than one desired function that needs to …

Locking Solar Tracking Bushing, Benjamin James Reed, Andrew Donald Maas, Angel Navarro-Iniguez, John Vincent Bruner

Mechanical Engineering

The contents of this final design review (FDR) outline the progress made by a team of four mechanical engineering students at California Polytechnic State University, San Luis Obispo to solve the problem of torsional galloping in solar tracker panels since the preliminary design review. The project proposed by the sponsor, Christian Friedrich, on behalf of ARaymond is a design for a friction based braking system integrated into a redesigned bushing.

The CDR contains details about the system design, the design justification, the manufacturing plan, and design verification plan. In the system design section, the four manufacturing subsystems (bushing mount, actuation, …

Novel Hitch Cargo Cart, Cesilio Sanchez Ramirez, Lance Haidet, Richard Lontoc, Tyler Selinka

Mechanical Engineering

This document presents the engineering design process used to develop, manufacture, and test a new and improved iteration of a hitch cart prototype. This process was performed by a team of four mechanical engineering seniors as part of California Polytechnic State University, San Luis Obispo’s senior design pathway. The goal of this project was to develop a sturdy and reliable iteration of our sponsor’s hitch cart prototype, that integrated the functionality of a vehicle hitch cargo platform and that of a height adjustable cargo cart into a single streamlined and easy to use product. This design could be used by …

Modeling, Control And Estimation Of Reconfigurable Cable Driven Parallel Robots, Adhiti Raman Thothathri

All Dissertations

The motivation for this thesis was to develop a cable-driven parallel robot (CDPR) as part of a two-part robotic device for concrete 3D printing. This research addresses specific research questions in this domain, chiefly, to present advantages offered by the addition of kinematic redundancies to CDPRs. Due to the natural actuation redundancy present in a fully constrained CDPR, the addition of internal mobility offers complex challenges in modeling and control that are not often encountered in literature.

This work presents a systematic analysis of modeling such kinematic redundancies through the application of reciprocal screw theory (RST) and Lie algebra while …

Novelty Ice Cream Assembly Prototype, Mason Sylvester, Logan Williamson, Alvaro Martinez, Adin Gilman-Cohen

Mechanical Engineering

Cool Beans USA is a novelty ice cream startup company founded by Keith Zachow. In the winter of 2022, our team began working with Mr. Zachow to develop a machine to automate parts of the production process for his product. This product consists of two hemispherical ice-cream cone shell halves filled with soft serve ice cream and pressed together. The assembled pods are around the size and shape of a small walnut and are intended to be sold in stores as a frozen finger food. At the time of project inception, this product was in its early stages and was …

Baby Soothing Device, Grace Kalene Mekrut, Matteo Gozzini, Miles Angel Ibarra, Christian Joel Roberts

Mechanical Engineering

This document is the official final design review for the Baby Soothing Device. This product is intended to help families sleep throughout the night by allowing a baby to be soothed back to sleep without constant and direct parental interaction. It is maintained by Mechanical Engineering students at California Polytechnic State University, San Luis Obispo for Dustin Yoder, the project sponsor. The purpose of this document is to present the design process from ideation to finished design in great enough detail that its manufacturing procedure may be replicated if desired. This document further explains all the research, testing, and benchmarks …

Analysis Of Propeller Designs Focusing On Lowering Sound Pressure Level Through Reduced Tip Loading, Luca A. Zeitvogel

Theses and Dissertations

This research focused on potential design optimizations for small propellers. Designs sought to reduce noise generated without sacrificing efficiency by “unloading” the propeller tip by reducing angle of attack near the tip. To see if nearfield performance improvements translated to a reduction in farfield sound pressure level, farfield experimental acoustic testing was performed on propellers that had been measured experimentally in the nearfield. The farfield results provided limited insight due to an equipment malfunction during testing. However, a large data set was obtained, which provides opportunities for future analyses. A computational simulation sought to recreate some of the nearfield experiments …

Multiple Heat Exchanger Cooling System For Automotive Applications – Design, Mathematical Modeling, And Experimental Observations, Zaker Syed

All Dissertations

The design of the automotive cooling systems has slowly evolved from engine-driven mechanical to computer-controlled electro-mechanical components. With the addition of computer-controlled variable speed actuators, cooling system architectures have been updated to maximize performance and efficiency. By switching from one large radiator to multiple smaller radiators with individual flow control valves, the heat rejection requirements may be precisely adjusted. The combination of computer regulated thermal management system should reduce power consumption while satisfying temperature control objectives. This research focuses on developing and analyzing a multi-radiator system architecture for implementation in ground transportation applications. The premise is to use a single …

Infusing Kirigami Principles Into Design Of Mechanical Properties, Hesameddin Khosravi

All Dissertations

The emergence of mechanical metamaterials — which derive their properties primarily from the underlying architecture rather than the constituent material — has unleashed a new era of material design and functionalities. To fully materialize the promising potentials of metamaterials, it is crucial to develop versatile, scalable, and easy-to-fabricate methods that can both generate and tailor the underlying periodic architecture. To this end, we propose the use of kirigami — a popular recreational art of cutting and manipulating paper — as a platform to create periodicity and super-stretchability. Kirigami has become a design and fabrication framework for constructing metamaterials, robotic tools, …

Performance Comparison Of Several Control Algorithms For Tracking Control Of Pantograph Mechanism, Laylaa Mahmoud Eng, Mohamed Shamseldin Dr, Mohamed Sallam Dr, Abdelghany Mohamed Prof

Future Engineering Journal

A sort of parallel manipulator known as a pantograph robot mechanism was created primarily for industrial requests that required high precision and satisfied speed. While tracking a chosen trajectory profile requires a powerful controller. Because it has four active robot links and one robot passive link in place of just two links like the open chain does, it can carry more loads than the open chain robot mechanism while maintaining accuracy and stability. The calculated model for a closed chain pantograph robot mechanism presented in this paper takes into account the boundary conditions. For the purpose of simulating the dynamics …

Theoretical And Experimental Analyses Of Acoustofluidic Phenomena For Biosensing Applications, Pradipta Kr. Das

USF Tampa Graduate Theses and Dissertations

Acoustofluidics is a well-proven tweezer serving various applications such as particle manipulation, cell trapping and separations, fluid mixing, and bio-sensing. In this thesis, we explored several aspects of acoustofluidics such as acoustic streaming, acoustothermal heating and acoustophoretic manipulations of micron sized objects, in the context of biosensing applications.

In Chapter 2, inner acoustic streaming for second-order fluids has been studied analytically by employing asymptotic expansions for thin Stokes layer and low acoustic Mach number. In addition, a multiple-time-scale approach has been adopted to separate the primary oscillatory flow and the steady acoustic streaming. The study considers two sample cases: (i) …

Multi-Robot Symbolic Task And Motion Planning Leveraging Human Trust Models: Theory And Applications, Huanfei Zheng

All Dissertations

Multi-robot systems (MRS) can accomplish more complex tasks with two or more robots and have produced a broad set of applications. The presence of a human operator in an MRS can guarantee the safety of the task performing, but the human operators can be subject to heavier stress and cognitive workload in collaboration with the MRS than the single robot. It is significant for the MRS to have the provable correct task and motion planning solution for a complex task. That can reduce the human workload during supervising the task and improve the reliability of human-MRS collaboration. This dissertation relies …

Aerodynamics And Vibrations Of A Helicopter Rotor Blade, Mohammad Khairul Habib Pulok

LSU New Orleans Theses and Dissertations

The nature of the aerodynamic environment surrounding a helicopter causes a significant amount of vibration to its whole body. Among different sources of vibrations, the aerodynamic loading on the main rotor blade is the major contributor. Therefore, analyzing a rotor blade's vibration characteristics and aerodynamic behavior becomes essential. The vortex characteristics and the wake surrounding a helicopter rotor blade play an important role because they affect the aerodynamic behavior of the rotor blade. An advanced mathematical and computational model of rotor wake and blade vortex gives a better understanding of the helicopter rotor dynamics. This study develops computational models of …

Bbt Acoustic Alternative Top Bracing Cadd Data Set-Norev-2022jun28, Bill Hemphill

STEM Guitar Project’s BBT Acoustic Kit

This electronic document file set consists of an overview presentation (PDF-formatted) file and companion video (MP4) and CADD files (DWG & DXF) for laser cutting the ETSU-developed alternate top bracing designs and marking templates for the STEM Guitar Project’s BBT (OM-sized) standard acoustic guitar kit. The three (3) alternative BBT top bracing designs in this release are
(a) a one-piece base for the standard kit's (Martin-style) bracing,
(b) 277 Ladder-style bracing, and
(c) an X-braced fan-style bracing similar to traditional European or so-called 'classical' acoustic guitars.

The CADD data set for each of the three (3) top bracing designs includes …

Control And Planning For Mobile Manipulators Used In Large Scale Manufacturing Processes, Joshua T. Nguyen

LSU Master's Theses

Sanding operations in industry is one of the few manufacturing tasks that has yet to achieve automation. Sanding tasks require skilled operators that have developed a sense of when a work piece is sufficiently sanded. In order to achieve automation in sanding with robotic systems, this developed sense, or intelligence, that human operators have needs to be understood and implemented in order to achieve, at the minimum, the same quality of work. The system will also need to have the equivalent reach of a human operator and not be constrained to a single, small workspace. This thesis developed solutions for …