Mechanical Engineering Commons^™

Fungi In Flux | Designing Regenerative Materials And Products With Mycelium, Arvind Bhallamudi

Masters Theses

As the world grapples with the escalating crisis of climate threats and environmental degradation, this research delves into the synergistic potential of design and biology, developing safe and sustainable materials for applications in prototyping, furniture and interior design. Harnessing the power of a unique organism - fungi, the study proposes an accessible, efficient, and resilient material resource system. It utilizes local waste streams and mycelium (the vegetative part of fungi) to grow functional structures. An experimental and small-scale protocol is modeled by testing bio-fabrication and bio-printing methods. The composites' performance qualities and characteristics are evaluated through mechanical testing and a …

Flat Plate Solar Collector For A Tiny Home, Clarice Leslie Nicholas

Honors Projects

Pallet Shelter is a company that builds tiny houses for the homeless. We partnered with them to build a solar water heater for their homes so that their tenants can have hot running water. The collector panel sits on the roof of the shelter and absorbs the energy of the sun and uses it to heat water flowing through an array of copper pipes. The hot water is then stored in an insulated tank inside the shelter.

A High-Speed Portable Ground Heat Exchanger Model For Use In Various Energy Simulation Software, Ryan Davies, Matt Mitchell, Edwin Lee

Macalester Journal of Physics and Astronomy

A portable component model (PCM) of a ground source heat pump system was developed and used as a test case in the creating of a PCM development framework. By developing this framework, new building energy simulation models will be able to be easily integrated into existing simulation software such as EnergyPlus and the Modelica Buildings Library. Our model uses a time responsive g-function and numerical methods to simulate ground source heat pumps for single time steps as well as long time scales. We validated our model against GHESim and GLHEPro and found that our model agrees with these two standards …

Fully Coupled Fluid Structure Interaction Simulation Of Bioprosthetic Heart Valves: A Numerical And Experimental Analysis, Masod Sadipour

Electronic Theses and Dissertations

Aortic stenosis impacts approximately 7% of the global population. In the past decade, the role of computational modeling has been becoming considerably important in the design of BHVs. To obtain reliable solutions in computational modeling, it is essential to consider accurate properties of bioprosthetic heart valves (BHVs), such as density and mechanical properties. Previous computational studies assumed (bovine pericardium) BP used in BHVs density was comparable to water or blood. Yet, BP is subjected to multiple treatments like fixation and anti-calcification. In Chapter 2, I measured BP density and its effect on BHV leaflet stress and strain. In the second …

The Modernization Of Large Power Transformer Tanks, Babajide O. Williams

Electronic Theses and Dissertations

Due to the current demands placed on the power grid in terms of climate change, increasing urbanization, and terrorist attacks, the U.S. government in response to these demands, mandated that all the grid components be modernized in order to increase their reliability. As a critical component of the grid, Large Power Transformers (LPTs) play a key role in ensuring sustainable power generation and distribution. A literature search performed in this work and the analysis of data retrieved from the search showed that the tanks of these LPTs are critical to their durability, longevity, and reliability. Therefore, the reliability of LPTs …

Recor-Diy, Maxwell W. Ferrer

Industrial and Manufacturing Engineering

RecorDIY is an affordable alternative to ordering Vinyl Records from a manufacturer in the form of an at-home record-cutting lathe. This report will cover the record cutting process from audio to physical, at home record lathes that are currently available, and the possible improvements that I plan to implement in order to make these devices a more viable alternative for small artists. Current models can only create low fidelity records, specifically they struggle with lots of “noise”, extra sounds such as static that make it harder to hear the actual audio. Another issue is record size, as current models can …

Morphology And Hemodynamics Of Cerebral Arteries And Aneurysms In A Rare Pair Of Monozygotic Twins, Hang Yi, Zifeng Yang, Luke C. Bramlage, Bryan R. Ludwig

Mechanical and Materials Engineering Faculty Publications

In this preliminary study, the underlying pathophysiology mechanisms of cerebral aneurysms (CAs) in monozygotic twins (MTs) were investigated via a rare pair of MTs (twin A and twin B) involving four reconstructed arterial models using preclinical information. First, dimensions and configurated outlines of three-perspective geometries were compared. Adopting an in-vitro validated numerical CA model, hemodynamic characteristics were investigated in the MTs, respectively. Despite expected genetic similarities, morphological comparisons show that configurations of cerebral arteries exhibit significant differences between the twins. The ICA size of twin A is larger than that in twin B (2.23~25.86%), varying with specific locations, attributing to …

Drop Test Release Mechanism, Sophie M. Getty, Matthew A. Tichenor, Nash W. Levy, Connor D. Dilloughery

Mechanical Engineering

Many boxes for shipping undergo drop tests by the manufacturer to ensure their durability. Certain constraints are necessary to successfully carry out these tests such as not damaging the box prior to the drop and maintaining consistency throughout every drop.

Our team has designed a Drop Test Release Mechanism that addresses these constraints. It provides repetitive drops for different objects that vary in shape and size such as small electronics or parts. This device utilizes a soft-clamping mechanism that can release an object with minimal force applied onto it prior to drop. A frame made of 80/20 was designed to …

Animatronic Monarch Butterfly: Mechanical System, Janine Rae Moreno, Enrico Cruz, Alexia Murphy, Lakshmanan Muthukaruppan

Mechanical Engineering

This report describes the design, manufacturing, and design verification of an interactive animatronic monarch butterfly created by a team of mechanical and computer engineering students for the Girl Scouts of California's Central Coast. The purpose of the project is to engage Girl Scouts in learning about monarch butterflies and provide hands-on experience in robotics and STEM. The report covers design changes, manufacturing processes, and assembly of various components, including the butterfly body, wings, legs, and electronic housing. The software and electronics used in the project are also briefly discussed, as the computer engineering team was responsible for the software and …

Cooled Liquid Rocket Thrust Chamber, Benjamin Gibson, Kealan Frederick Harris, Ryan Frank Schackel, Bjorn Thorsen

Mechanical Engineering

Cooling may affect the thrust output of a small-scale rocket. Little research is published about small-scale rocket performance. We hypothesize the thrust produced varies as the amount of cooling varies. To facilitate assessing this hypothesis, we have designed and built a liquid rocket engine rated for at approximately 25 lb_f of thrust. Our objective was to build in parallel with Cal Poly Space Systems, who built a rocket engine with similar specifications except without cooling. Our challenge is to integrate film cooling, so that the effects of cooling may be compared to Cal Poly Space System’s engine which has …

Thermoacoustic Refrigerator, Rees Phillip Verleur, Colleen Farrell Mccandless, Anders Matthew Bjork, Yashraj Ashwinkumar Solanki

Mechanical Engineering

In the Thermoacoustic Refrigerator Cal Poly Mechanical Engineering senior project, we designed, built, and tested a thermoacoustic refrigeration system which achieved an average temperature difference of 11.0°C. Our system consists of a resonator tube with an instrumented stack, mounted onto a base with a speaker and amplifier. An external power supply and function generator provide the power and signal to the system, and a thermocouple reader displays the temperature of the top and bottom of the stack. The system consistently achieved a significant temperature difference between the two ends of the stack in various ambient conditions, and it was quick …

Statistical Uncertainty Of The Ignition Time, Burning Rate, And Extinction Characteristics Of Engineered Timber Products, Jacob David

Master's Theses

The characterization of flammability parameters such as time to ignition, mass loss rate (MLR), and extinction criteria is critical for understanding ignition and burning behavior of timber products. These parameters, often determined with bench scale experiments, have previously been presented in literature. However, standard test methods generally use relatively low trial quantities (e.g., n=3) which can potentially cause large variation in reported values. This study investigates the influence of trial quantity on observed statistical variation in key flammability metrics for timber products (e.g., ignition time, peak MLR, MLR at extinction). Using a conical heater, 100 repeat trials were conducted …

Development Of A Low-Cost Acoustic Gauge For Simultaneous Tide And Wave Measurement, Alexander Kalman Dunn

Master's Theses

High-quality tide and wave data are essential in a variety of fields including coastal engineering, climate science, disaster response, and recreational activities. Accurate data are publicly accessible from government organizations such as the National Oceanic and Atmospheric Administration (NOAA), however the high costs associated with deploying and maintaining their high accuracy gauges results in a deficit of localized data. Commercial gauges available starting at $2,000 are still expensive for local agencies and individual users to deploy and maintain. These commercial options can also be limited in their scope, accuracy, or ease of use. In this thesis, a low-cost acoustic gauge …

Gas Metal Arc Welding With Undermatched Filler Wire For Hot-Press-Formed Steel Of 2.0 Gpa Strength: Influence Of Filler Wire Strength And Bead Geometry, Dong-Yoon Kim, Cheolhee Kim, Tae Hyen Lee, Minjung Kang, Junhong Park

Mechanical and Materials Engineering Faculty Publications and Presentations

Commercial welding filler wires have less strength than hot-press-forming (HPF) steels. As the 2.0 GPa-HPF steel sheets have been released, their lap welding characteristics were investigated using gas metal arc welding in this study. The base metal was 1.1 mm-thick 2.0 GPa-HPF steel sheets, and three filler metal wires considered in this study (W540, W920, and W980) had tensile strengths of 540, 920, and 980 MPa, respectively. Gas metal arc welding was performed under a controlled short-circuit mode, and the wire feed speed (WFS) was selected as a process parameter. Tensile-shear test and microscopy were performed to evaluate the joint …

Biomechanical Knee Joint For Exoskeleton, Gabriel Ireton Ahern, Calloway Miller, Christianna Altamura, Eric Mailes

Mechanical Engineering

Our senior design project consisted of designing and manufacturing a biomechanically accurate, actuated knee joint to be integrated into an exoskeleton being developed by the Lower Limb Exoskeleton Assist Project (LLEAP), a part of the EMPOWER student association at Cal Poly, San Luis Obispo. As the human knee flexes and extends throughout gait motion, the center of rotation changes. Currently marketed exoskeletons have one point of rotation, which over constrains the knee and causes misalignment between the user and the suit [1]. Our goal was to mimic natural knee joint motion by changing the center or rotation, thus reducing misalignment …

Turbine Integrated Pitching System, Elizabeth Costley, Josephine Maiorano, Jeff Larson, Cameron Jackson

Mechanical Engineering

The Cal Poly Wind Power Club (CPWP) tasked this senior project to design, manufacture, test, and deliver a mechanism to pitch the blades for their small-scale horizontal axis wind turbine. CPWP competes in the Collegiate Wind Competition (CWC) against schools across the country, and as such it was critical to comply with the provided competition rules in addition to the design requirement from CPWP. The purpose of the pitching mechanism is to improve the performance and efficiency of the wind turbine by allowing the blades to adjust angles with different wind speeds. Specifically, this project aimed to minimize hub size, …

Prove Primary Battery Structure, John D. Burkhart, Andy Mccormick, Ryan Yu, Soren Barclay

Mechanical Engineering

In conjunction with Prototype Vehicle (PROVE) Laboratory, our group designed, manufactured, and tested a prototype structure to house the battery boxes for PROVE’s endurance vehicle. Our structure was designed to support the batteries during normal use, and in the event of a front crash. Our design is comprised of a secondary composite box to house the battery boxes, a bottom plate to affix the secondary box to the chassis floor, a horizontal plate fastened to the chassis, and a brace structure welded to the chassis. From the outset, we chose to use a secondary box, the primary battery boxes must …

Rapid Composter, Shannon Shinozaki, Avin Atencio, Jonathan Fraser, Lukas Kolbl, Russell Occhipinti

Mechanical Engineering

This project was created with the intent of automatically composting equine bio waste to be reused as plant fertilizer. The system consists of four subsystems: power generation and storage, automatic controls, aeration, and structure. Each subsystem may be manufactured independently, then put together. This system will not have access to power outlets, so it was designed to be solar-powered.

Parametric Bicycle Yoke, Colin Reay, Walter Minehart, Robby Harrigan, Jordan Olson

Mechanical Engineering

This report outlines the entire design, fabrication, and validation process of a parametric yoke design that addresses the packaging problem of the bottom-bracket chainstay junction in modern bicycle frames. The goal was to create an elegant, space-efficient solution that is accessible to the Cal Poly Bike Builders Club. The report includes documentation of the three-part fixture system, manufacturing process, and testing results for the yoke.

Our yoke design outperforms traditional round-tube weldments in torsional and vertical stiffness. Additionally, all manufacturing fixtures and machining operations function as intended, resulting in a finished yoke that meets all required tolerances in under an …

Treadmill Platform For Quadrupedal Robots, Baxter J. Bartlett, Jack F. Butler, Phillip A. Shafik, Tarun S. Ganamur

Mechanical Engineering

Cal Poly Legged Robots, led by Professor Refvem and Professor Xing, has been leading Cal Poly’s attempts to simulate, produce, and test their legged robots. The initial testing of the locomotion of these robots can be dangerous to the robot since any bugs in the code could cause the robot to fall over and harm itself. Our responsibility as a team was to deliver a portable platform for testing the locomotion capabilities containing a fall prevention mechanism. In short, we have designed a platform for this purpose that consists of a treadmill surrounded by a wheeled chassis with a system …

Perforated Groove Cam Lock, Matthew J. Redmond, Samuel A. Potter, Dylan Weiglein, Andrew Reese

Mechanical Engineering

NASA Artemis III astronauts need a way to attach and detach various tools to an extension handle to be used during lunar EVA sample collection. Because lunar dust is so harsh and abundant, mechanisms must be designed to function regardless of the number of contact particulates. Past designs used on the Apollo missions proved to be problematic for their operators, opening the door for innovative improvement. A new mechanism has been proposed that directly addresses the performance issues of the original handle extension mentioned in NASA’s Apollo mission reports. The new mechanism boasts an open design that promotes dust tolerance …

Backflow Relief Valve Test Stand, Olivia Mcnulty, Wiill Halvorsen, Ryan Dubois, David Leaman

Mechanical Engineering

This Final Design Review (FDR) document details the final design, manufacturing, testing, and results of the Zurn Wilkins Backflow Relief Valve Test Stand Project under the sponsorship of Brian Yale and Rueben Westmoreland. This project involves simulating real-world conditions of static pressure and water hammer cycling. The stand will give Zurn Wilkins’ engineers a method by which to test their relief valves prior to a rigorous, yearlong University of Southern California (USC) testing procedure. Our design involves using city water, a pump, a Zurn backflow preventer, and a control system to apply specific pressures to each end of the relief …

Saver: Surface Autonomous Vehicle For Emergency Rescue, Lucas Je Sandsor, Michelangelo Coltelli, Brian Wong, Sebastion Rivero, Kobe Hayashi

Mechanical Engineering

The design, fabrication, and testing of an unmanned surface vehicle for the NASA Micro-G NExT SAVER challenge. This device features a radio direction finding phase array to autonomously navigate to an emergency distress beacon to deliver emergency supplies.

Power Thyristor Controller For Speed Control Of Dc Motor, Alejandra Zapata, Morgan Erich Boehme, Abdullah Mohammed Awidah, Payton Robert Chalstrom

Electrical Engineering

In this work, a Power Thyristor Controller for Speed Control of DC Motor has been developed with the purpose of replacing an existing simulation experiment, aiming to effectively implement the principle of learning by doing. The primary objective of the experiment setup is to illustrate the fundamental principles and operational mechanisms underlying the firing angle and controlled bridge rectifier. The new experiment is taking advantage of the existing FCRO4100 Single Phase Firing Board that was donated to the University by ENERPRO. The pre-programmed microcontroller is connected to the thyristor bridge rectifier that’s powered by 24VAC. Additionally, a DC motor will …

A Hybrid Admm For Six-Degree-Of-Freedom Entry Trajectory Optimization Based On Dual Quaternions, Chaoying Pei, Changhuang Wan, Ran Dai, Jeremy R. Rea

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This article investigates the six-degree-of-freedom (6-DoF) entry trajectory optimization problem in a Human-Mars entry, powered descent, and landing mission. During the entry phase, aerodynamic forces are employed to decelerate the vehicle. Instead of being treated as a point mass, both translational and rotational motions of the entry vehicle are considered. Specifically, the 6-DoF rigid body motion of the entry vehicle is modeled using the unit dual quaternion representations to avoid highly nonlinear terms in the flight dynamics expression originally based on the flight-path coordinates. Then, the entry trajectory optimization problem is to minimize the terminal speed subject to dynamical, operational, …

Improving Autonomous Vehicles Operational Performance Using Resilience Engineering, Johan Fanas Rojas

Dissertations

Autonomous vehicles are expected to revolutionize the transportation industry by providing a safer and more efficient means of transportation. However, as autonomous vehicles are deployed on public roads, they are exposed to significant risks, both in terms of safety and system performance. Recent studies have highlighted a range of errors and accidents associated with autonomous vehicles, underscoring the need for a systematic approach to improve their operational resilience. Resilience engineering, a discipline focused on designing and analyzing complex systems to better cope with unexpected events and disruptions, offers a promising framework for addressing these challenges. Despite the potential benefits of …

Enabling Energy Efficiency In Connected And Automated Vehicles Through Predictive Control Techniques, Farhang Motallebiaraghi

Dissertations

The transportation sector is a significant contributor to global energy consumption and emissions, necessitating the development of sustainable transportation systems. In this regard, connected and automated vehicles (CAVs) have emerged as a potential solution to transform the transportation industry. By harnessing advanced mapping and location technologies, Vehicle-to-Vehicle (V2V) and Vehicle-to-Infrastructure (V2I) communication, CAVs offer the promise of improving efficiency, reducing traffic congestion, and enhancing safety and comfort. However, the adoption of CAVs also brings about various challenges, including energy efficiency concerns that need to be addressed to fully realize their potential benefits. This dissertation investigates energy-efficient control techniques for transportation …

Decomposition Of The Wall-Heat Flux Of Compressible Boundary Layers, Dongdong Xu, Pierre Ricco, Lian Duan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We use the method developed by Elnahhas and Johnson ["On the enhancement of boundary layer skin friction by turbulence: An angular momentum approach," J. Fluid Mech. 940, A36 (2022)] and Xu et al. ["Decomposition of the skin-friction coefficient of compressible boundary layers," Phys. Fluids 35, 035107 (2023)] for the decomposition of the skin-friction coefficient to integrate the mean temperature equation for high-Reynolds-number compressible boundary layers and arrive at an identity for the decomposition of the wall-heat flux. The physical interpretation of the identity and the limitations of this approach are discussed. We perform an integration on the mean temperature equation …

Utilizing Machine Learning Models To Estimate Energy Savings From An Industrial Energy System, Eva Mclaughlin, Jun-Ki Choi

Mechanical and Aerospace Engineering Faculty Publications

Energy audits are an important part of reducing energy usage, costs, and carbon emissions, but there have been discrepancies in the quality of audits depending upon the auditor, which can negatively affect the impacts and credibility of the energy assessment. In this paper, historical energy auditing data from a U.S. Department of Energy sponsored research program was gathered and analyzed with a machine-learning algorithm to predict demand savings from a compressed air system assessment recommendation in industrial manufacturing facilities. Different energy auditors calculate savings for repairing leaks in compressed air systems in various ways, so the energy demand savings have …

Tie Installer For Great Heights To Extend Research, William Moffat, Truman Giesen, Ryan Ghosh, Victor Rodriguez

Mechanical Engineering

This senior project consisted of developing and creating a hand held device that automatically installed zip-ties. Our project began as an entry to the NASA Micro-G NExT competition but was redirected towards the new goal of creating a consumer product.

Although installing zip-ties seems to be quite a simple process, throughout the entirety of our development we quickly determined that our device would have to embrace a higher level complexity to complete the objective of installing a zip-tie. The ultimate drive force of this project was meant to create a solution for the massive cost gap of already existing Zip-tie …