Mechanical Engineering Commons^™

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 …

Unmanned Aerial Vehicle-Based Computer Vision For Structural Vibration Measurement And Condition Assessment: A Concise Survey, Kai Zhou, Zequn Wang, Yi Qing Ni, Yang Zhang, Jiong Tang

Michigan Tech Publications

With the rapid advance in camera sensor technology, the acquisition of high-resolution images or videos has become extremely convenient and cost-effective. Computer vision that extracts semantic knowledge directly from digital images or videos, offers a promising solution for non-contact and full-field structural vibration measurement and condition assessment. Unmanned aerial vehicles (UAVs), also known as flying robots or drones, are being actively developed to suit a wide range of applications. Taking advantage of its excellent mobility and flexibility, camera-equipped UAV systems can facilitate the use of computer vision, thus enhancing the capacity of the structural condition assessment. The current article aims …

Implementation Of Topology Optimization Into The Mechanical Design Process, Nolan Clapp

Master's Theses

Topology Optimization is a lightweighting method based on finite element analysis that produces a part with optimum material distribution in the design space. Results from topology optimization often have organic shapes and curves that are difficult if not impossible to machine with traditional subtractive manufacturing methods. This paper analyzes the implementation of the Solidworks® Topology Optimization add-in into the mechanical design process and discusses required postprocessing to ensure manufacturability of the optimized part though a case study on two example parts. Results of traditional optimization, topology optimization and “selective” optimization (optimization using the results from topology optimization to selectively remove …

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 …

Gradient-Based Trade-Off Design For Engineering Applications, Lena A. Royster, Gene Hou

Mechanical & Aerospace Engineering Faculty Publications

The goal of the trade-off design method presented in this study is to achieve newly targeted performance requirements by modifying the current values of the design variables. The trade-off design problem is formulated in the framework of Sequential Quadratic Programming. The method is computationally efficient as it is gradient-based, which, however, requires the performance functions to be differentiable. A new equation to calculate the scale factor to control the size of the design variables is introduced in this study, which can ensure the new design achieves the targeted performance objective. Three formal approaches are developed in this study for trade-off …

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 …

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 …

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, …

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 …

Wave Energy Converter For Marine Vessels And Isolated Communities, Leo Kirshenbaum, Owen Pyle, Gage Howard, Charlie Camilli, Jonathan Ma, Emigdio Islas, Joseph Bonafede

Mechanical Engineering

California Polytechnic State University’s 2023 Marine Energy Collegiate Competition team, Surf Supply, has developed a floating dock that transduces wave energy into electricity. The following report aligns with MECC requirements, and our design changes since CDR are present in the User Manual in Appendix F. Our primary market research of the Blue Economy identified electric marine vessel charging and isolated communities as early adopters that could benefit most from the first generation of our wave energy converter (WEC). Surf Supply’s design concept provides a reliable, affordable, and renewable energy source that reduces dependency on conventional fossil fuels, allowing blue economy …

Headlamp/Bike Light Damping System, Ethan Reece Clark, Alec Stonehouse, Omeed Ostry, Mitchel Anderson

Mechanical Engineering

The task for this project is to design a headlamp and/or bike light that absorbs the impact shocks from the user’s actions. The user that the system is being designed for may be riding a bike or running on a trail in the evening or early in the morning where the light needs to be stabilized and their path must be illuminated. This report presents the final design chosen after months of prototyping and design iteration. It encompasses the system design, design verification through testing, implementation, future recommendations, and lessons learned throughout the process. The chosen design utilizes a fully …

Weed Robot, Kaela Stern, Lewis Kanagy, Claire Franz, Carlos Rodriguez Orozco, Jackie Chen, Sachi Hiji, Ayush Kakkanat, William Ta

Mechanical Engineering

Team Weed Scouts has completed our work on a weed-cutting robot for the Girl Scouts of California’s Central Coast. The final robot build provides a solid foundation that can be built and improved upon by future teams. We have completed the robot base and structure, including the chassis, drivetrain, and robot shell. We also completed manufacturing a weed storage bin and canvas cover for the robot. Additionally, we have built a weed scooper, the mechanism that cuts weeds and transports them into a storage compartment. The electronics and programming for remote control of the robot are also implemented. After some …

Flexible Water Cooling, Joshua Terlaje, Andrew Lin, Nicholas Morales, Tanner Parrott

Mechanical Engineering

The goal of this project is to develop and deploy a water-cooling system to reduce the danger of heat exhaustion among communities of farmworkers. Currently, it is difficult to keep chilled water available throughout the workday when using portable water coolers. The idea uses a refrigeration system to chill the water supply by using the power take-off (PTO) on farm equipment and a corresponding generator to get around this restriction.

The project places a strong premium on keeping the chilled water supply at a maximum temperature of 59°F to ensure compliance with the California Department of Industrial Relations' requirements. Each …

In-Situ Mechanical Tester, Andrrew Murach, Gustavo Marquez, Kosimo Tonn, Jake Vormbaum

Mechanical Engineering

Over the course of the 2022-23 Cal Poly SLO school year, a small tensile tester device was developed specifically for Dr. Long Wang to test thin film materials under a microscope and generate accurate force versus displacement graphs. A tensile tester was manufactured using purchased and machined components, electronics were consolidated in a separate box and connected, and a program and user interface were written to control the motion, provide custom inputs, and organize useful data for the researcher. Tests were conducted to compare the performance of the device to universal tensile testers available in the Composites lab. The device …

Metamaterial-Based Soft Actuators, Savannah June Cheney, Nathan Kessenich, Marco Leen, Merek Mcgill

Mechanical Engineering

For this project the team was tasked with designing a soft actuator that incorporated aspects of mechanical metamaterials. The team’s goal was to demonstrate the feasibility of structural metamaterials in the field of soft robotics and demonstrate a novel response with a final assembly. Also included in the team's discussion are the manufacturing steps, protype tests & results, and suggested future next steps. Following the previous report (critical design review) the team chose to follow the path of designing a continuum robot with metamaterials incorporated into the design. A continuum robot consists of a soft cylindrical body with rigid evenly …

Therapeutic Mechanical Horse Project, Broghan Martin, Carson Roff, Zach Barnisham, Lydia Barnes

Mechanical Engineering

This project team created a simple mechanical model of a horse that disabled children could ride on to feel more comfortable partaking in equine therapy. This project was sponsored by Jack’s Helping Hand as part of their equine therapy program. The team went through the entire design process of researching, ideating, prototyping, and testing to create the final product. Finite element analysis of the structural members of the horse was performed. The forces used in that model were later validated through testing of the strength of those same members after manufacturing. In the end, a self-actuating single degree of freedom …

Bespoke Bicycle Enclosure, Thomas Link, Kyle Mcafee, Marc Monier, Hunter Walden

Mechanical Engineering

Brian Higgins is an American veteran with retinitis pigmentosa who relies on cycling for transportation. The motivation for this project is to design and manufacture a refined prototype bicycle attachment to support him while biking in the rain and cold. The attachment will serve to enclose him for optimal protection from inclement weather, while maintaining sufficient mobility for daily cycling. Mr. Higgins’ bicycle is equipped with an attached sensor system which assists his visual impairment by using an ultrasonic sensor. Therefore, the attachment cannot adversely affect the function of the sensor system. The project timeline is set at approximately 7 …

Disc Golf Throwing Robot, Nevada S. Schultz, Sydney M. Lewis, Erick Edmundo Daza, Rachel Alysse Greenberg, Peter M. Kean

Mechanical Engineering

Disc golf companies need better methods to test disc flight. The scope of this project is to create a disc throwing robot that can throw a disc golf driver 450-500 feet, with control over the speed, spin, and release angle. Research shows that multiple disc-throwing products exist; however, none meet the full requirements of this project. The Cal Poly senior project design team created a proof-of-concept machine. This prototype started as a two-wheel mechanism. Eventually, a third wheel was added, allowing for complete control over disc spin. The three-wheel prototype reached 62 mph when perfectly calibrated. The prototype is accurate, …

Baja Sae Semi-Active Suspension, Cameron Paul Jones, Ethan Jacobi Mikel, Joshua Macguire Wright, Aditya Garg

Mechanical Engineering

This document outlines the design and justification for the final design of the Baja SAE Semi-Active Suspension Senior Project. The goal of the project was to build a base valve that can adjust suspension damping rates on the fly. This document details the ideation, design, manufacturing, design verification results, and detailed drawing package for the project. Additionally, this document includes information regarding the pressure drop calculator, O-ring calculations, and CAD. The manufacturing processes used to create the valve and the testing and evaluation of the valve are included as well. Finally, the methods that were used to manage this project …

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 …

Spheroidization Heat Treatment Conditions With Data Analysis In Medium Carbon Cr-Mo Steel For Ultra High Strength Cold Heading, Yong Deok Jo, Sung Yi, Byoung Lok Jang

Mechanical and Materials Engineering Faculty Publications and Presentations

The degree to which parameters affect the spheroidization heat treatment of steel was calculated by setting the spheroidization heat treatment conditions of Cr-Mo steel and using data analysis such as S/N ratio and ANOVA. After analyzing the transformation temperatures of the steel, A_c1 and A_c3, using a DSC, the conditions were set accordingly. The surface hardness was measured for the conditions and used as an evaluation index. The correlation was analyzed by comparing the spheroidized volume fraction and the surface hardness, and the Pearson correlation coefficient was -0.88, proving that a correlation existed between the two values. …

Measurement Of Polycyclic Aromatic Hydrocarbons (Pahs) On Indoor Materials: Method Development, Aurélie Laguerre, Elliott T. Gall

Mechanical and Materials Engineering Faculty Publications and Presentations

Wildfire smoke penetrates indoors, and polycyclic aromatic hydrocarbons (PAHs) in smoke may accumulate on indoor materials. We developed two approaches for measuring PAHs on common indoor materials: (1) solvent-soaked wiping of solid materials (glass and drywall) and (2) direct extraction of porous/fleecy materials (mechanical air filter media and cotton sheets). Samples are extracted by sonication in dichloromethane and analyzed with gas chromatography–mass spectrometry. Extraction recoveries range from 50–83% for surrogate standards and for PAHs recovered from direct application to isopropanol-soaked wipes, in line with prior studies. We evaluate our methods with a total recovery metric, defined as the sampling and …

Mechanics Desktop Lab Equipment, Dante Azpilcueta, Quentin F. Mormann, Arfan Ansar

Mechanical Engineering

This paper overviews the design, implementation and testing of a senior project designed to fix the issue of there being no lab equipment or space for content pertaining to mechanic of materials topics. This is of concern as Cal Poly is reorganizing content as it switches to the semester system and is in need of labs for this material. The solution found was to create a portable miniature universal test machine that could be carted into non-lab classrooms. The goal was to create a device that was low-cost, modifiable, durable, easy to manufacture and repair as these were the qualities …

Valve Efficiency Testing Device, Jake Robert Rydberg, Andrew Keith Willardson, Jake Ben Jezier, Emily Marie Wannenmacher

Mechanical Engineering

This document serves as the official Final Design Review (FDR) for the mechanical engineering team on the Valve Efficiency Testing Device project for the Phillips 66 Rodeo Refinery. The team attends California Polytechnic State University, San Luis Obispo. The project involved designing and building a valve efficiency testing device. The goal was to create a finished test device that can be used in the Phillips 66 Rodeo Refinery machine shop to test reciprocating compressor valves before they are installed. The purpose of this document is to describe the manufacturing and design verification activities that have been completed since Critical Design …

The Center For Centering Dome, Olek Piechaczek, Ryan M. Scharf

Architectural Engineering

The Center for Centering seeks to create a large-scale healing center, conducive to individual centering of the mind and body. This mobile installation provides a relaxing, enclosed space while still maintaining a connection to the outdoors. The clients liked the idea of having a pop-up installation that could be easily set up as a touring display. With a deadline for installation looming in June 2022, a team of students had five months to design and manufacture the structure.

In winter 2022, the students developed custom geometry to minimize the number of individual parts and built a ¼ scale model of …