Mechanical Engineering Commons^™

Hitch Cart “Landing Gear”, Rebekah White, Jose Raygoza, Randy Hernandez, Brandon Leon

Mechanical Engineering

This report aims to allow our sponsor, to review our design process of the Hitch Cart Landing Gear Prototype. In the design overview section of this report, we discuss the primary design modifications we made to the wheel mechanism of the existing hitch cart prototype, including the addition of the ACME screws and the folding brackets. This allows our sponsor to see the intended improvements made to the past prototype and understand the primary goal of our project. Then, in the implementation section, we cover the entire manufacturing process to allow our sponsor to understand what manufacturing steps must be …

Pseudo Gps For Romi, Emmanuel Baez, Owen Guinane, Gabriel Coria, Conor Schott

Mechanical Engineering

The Pseudo-GPS system for Romi robots addresses the need for precise real-time location tracking in Cal Poly's Mechatronics lab. This project, developed by Emmanuel Baez, Gabriel Coria, Owen Guinane, and Conor Schott, under the guidance of instructor Charlie Refvem, provides a proof-of-concept system to enhance the Romi robots' geolocation capabilities for advanced robotic algorithms.

The proposed system uses a Raspberry Pi 4 equipped with a Pi camera module and ArUco markers to track the position and orientation of Romi robots within a lab environment. Custom 3D-printed stands secure markers on the robots, and a designated origin marker defines the coordinate …

Expandable And Retractable Wheel Design, Ethan Fortenberry, Emily Cottrell, Keegan Martin, Benjamin Mcconnell

Mechanical Engineering

Our sponsor, Jeremy Goren, wants to see his patented expandable wheel design come to life. He requires a functional final product actuated by linear actuators and with a continuous, circular outer shell. The overall design can be broken up into 2 parts: the inner hub and outer shell. The wheel's shell will consist of a 12-piece outer shell that guides the 6 inner shell pieces. The outer shell pieces will be connected via a UBracket. The hub will consist of 3 identical parts that will hold 2 linear actuators each. The pieces will be bolted together to create 1 singular …

The Waterbug: Adaptive Paddle Board Frame, Remy James Elio Lacchia, Katie Kellum, Madeline Evenson, Shelbi Sullaway

Mechanical Engineering

People with disabilities, particularly wheelchair users, face limitations in participating in outdoor activities like paddleboarding. Central Cal Adaptive, a nonprofit organization, aims to bridge this gap by offering adapted paddleboarding experiences. However, their current paddleboard presents challenges such as portability, range of motion, stability, and safety. Our team, comprising Madeline Evenson, Remy Lacchia, Katie Kellum, and Shelbi Sullaway, has collaborated with Central Cal Adaptive to refine the existing paddleboard design. The team’s goal is to enhance the paddleboard's functionality to better cater to wheelchair users' needs, ensuring lightweight, portable, and safe features for an improved outdoor experience.

Our paddleboard concept …

Piston Crown Design, Kurt L. Lippmann, Liam T. Janssen, Alex Rangel, Larry J. Davis

Mechanical Engineering

This project investigates the effects of dimpling a piston crown, and its impact on engine combustion dynamics. Through computational methods, the effects of piston crown dimpling on flow characteristics were evaluated. Theoretical results were verified with experimental methods. Experimental methods included characterization of exhaust gas content, engine horsepower and torque, and exhaust opacity.

Swim Fly Drone, Alia Wolken, Sha'anan Levy, Andrew Jwaideh, Eduardo Santos

Mechanical Engineering

This project addresses the need for a versatile drone that is capable of operation in both air and water environments, with potential applications in infrastructure inspection, defense, search and rescue, and ocean exploration. This project focuses on the design and development of a waterproof aerial drone capable of floating on the water surface and submerging underneath to controlled depths with the integration of a custom detachable buoyancy chamber. The buoyancy chamber design utilizes syringes to compress and decompress air inside of the chamber, changing the volume of the chamber, with an actuation system controlled by a closed-loop control system that …

Finite Element Analysis And Verification Of Transverse Mechanical Properties Of Generally Cylindrical Orthotropic Constitutive Modeling Of 3-Phase Nanocomposite Unit Cell, Christopher J. Hawkins

Master's Theses

Fiber-reinforced composites are increasingly popular due to their specific strength and stiffness, making them ideal for high-performance applications. However, these materials primarily exhibit superior properties in-plane, while their out-of-plane characteristics remain comparatively weaker. Previous research has shown that the most effective method to enhance out-of-plane properties involves the incorporation of carbon nanotubes. Experimental tests have demonstrated significant improvements in properties such as tension, flexural, short beam shear, and fracture toughness. Alongside these experimental studies, analytical equations have been developed to predict the behavior of these composites under various loading conditions, including tension, bending, shear, and fracture. Existing models primarily address …

Zero-G Exercise Equipment, Charisse Biglete, Jake Brajevich, James Monroe, Ethan Siahpush

Mechanical Engineering

In a micro-gravitational environment, the body undergoes less loading than that found on Earth. This leads to muscular atrophy, Osteoporosis, decreases in protein synthesis, and various other undesirable outcomes. To prevent this, astronauts undergo a strict exercise regime to maintain their health. The current exercise equipment available for spacecraft is large, heavy, complicated to use, costly, and unsafe. There is a definite need for the re-engineering of the exercise equipment to be used by astronauts while in microgravity environments to rectify these issues.

Practical Model Of A Labview Controlled Active Magnetic Bearing On A Bently Rotor Kit Validated With Matlab And Msc Adams, Luis Herrera-Delgado

Master's Theses

This thesis aimed to model a rotor supported by an active magnetic bearing (AMB). The magnetic force equation due to a single electromagnet was first derived which served as the basis of AMB modeling. The finalized model utilized Matlab, Simulink, and MSC Adams to simulate a rotor supported by an AMB. Matlab and Simulink were used to model the AMB control system and actuator output. MSC Adams was used to capture the dynamics of a flexible rotor. This model was verified by comparing the model’s simulated vibration to real vibration data measured from a modified Bently Nevada rotor kit equipped …

Hypoxic Incubator: Improving Robustness/Reliability And Demonstrating Physiological Efficacy, Damon Dennis Tan

Master's Theses

The Microphysiological Systems Laboratory aims to develop colorectal cancer tumor models under a hypoxic environment to assess model response to pharmaceutical compounds in vitro. To perform relevant studies, researchers have attempted to use different hypoxic inducing strategies such as a nitrogen pod and hypoxic incubator to recreate in vivo physiological responses to hypoxia. However, studies would be interrupted due to incubator functionality failure. To ensure successful and physiologically relevant studies, I improved and verified the robustness and reliability of a hypoxic incubator previously designed and manufactured in the lab. Through the testing and iterating design processes, I engineered and implemented …

3d Printed Microfluidic Fabrication Methodology, Characterization, Mechanical Design, And Applications In Electrostatic Artificial Muscles And Benthic Microbial Fuel Cells, Terak B. Hornik

Master's Theses

The fabrication of microfluidic devices often requires specialized methods. The development of these methods requires careful characterization and understanding of the processes involved. Using primarily PolyJet 3D printing technology, microfluidics offers a wide scope of applications such as microfluidic benthic microbial fuel cells (MBMFCs) and electrostatic artificial muscles. MBMFCs benefit from the confinement of the microbes resulting in close proximity between the electrode and the organisms. Using a modular design called the Sponge, assembly and upscaling is possible. Electrostatic artificial muscles benefit from a microfluidic approach due to the non-linearity of electrostatic attraction creating disproportionate benefits when miniaturized. When designed …

Cryogenic Fuel Applications To Sustainable Commercial Aircraft, Jack R. Kisling, Lillian Panning

College of Engineering Summer Undergraduate Research Program

Finding a source of clean and renewable energy is one of the greatest challenges humanity will face in the 21st century. With populations expanding, developing countries increasing their use of resources, and the rapid and alarming effects of climate change, a shift to a sustainable future is an existential prospect.

The goal of our project is to take the first steps toward getting safety procedures and lab space established, so mechanical engineering senior projects can quickly begin to experiment with cryogenic fuels. They will explore the application of cryogenic fuels to commercial aviation.

Biomechanical Effects Of Worn-Out Shoe Outsoles And Insoles On The Human Foot, Yuka M. Iwashita, James A. Engebretson, Shreeshan Jena

College of Engineering Summer Undergraduate Research Program

The combination of outsole, midsole and insole layers of new shoes provide proper cushioning to the foot during the daily activities of life. Subsequently, the wear-based degeneration or damage to one or more of these sole layers can reduce the cushioning effect to the plantar surface of the foot. This reduction of cushioning effect can impact the distribution of stress concentration regions along the foot plantar surfaces and lead to foot pathologies. The present proposed research intends to study these effects of shoe-wear on the plantar surface of the human foot, using FEA (ABAQUS) and experimental methods. Commonly, the worn-out …

Computer Vision In A Robotic Arm, Jack Maxwell

College of Engineering Summer Undergraduate Research Program

We used a machine learning-based object detection algorithm to give a robotic arm the ability to "see" with its camera.

Surrogate Models For Stress-Strain Mapping Of Microscale Physics, Samuel Roach, Dr. Eric Ocegueda

College of Engineering Summer Undergraduate Research Program

•Learn the difference between different neural networks within machine learning (ML) •Develop a working understanding of the ML tool Pytorch and machine learning operator: Recurrent Neural Operator •Use MATLAB to create and process time dependent stress/strain matrices to display the hyper-parameters for different RNOs •Apply RNO to train the strain-stress mapping of tri-laminate and granular cases

Seismic Resilience Of Timber Homes, Melia R. Costa

College of Engineering Summer Undergraduate Research Program

The vast majority of residential buildings in California are wood-frame structures. A home is typically a very large investment for families, and damage to the home can be detrimental to a family’s economic success. Thus, reducing the economic impacts of an earthquake on residential timber housing is crucial. A full scale, two-story section of a residential timber house is in construction in the Parson’s Geotechnical and Earthquake Engineering Laboratory on the Cal Poly campus in San Luis Obispo, California. Once built it will be put through earthquake simulation tests on a shake table with various magnitudes of seismic activity. Next, …

Design Of Ballistics Armor Using Additive Manufacturing Of Kevlar Composites, Jedidiah D. Jimenez, Roha Y. Ali, Jack C. Bride

College of Engineering Summer Undergraduate Research Program

This project evaluates the effectiveness of various geometries created using advanced additive manufacturing (AM) of Kevlar fiber, chopped carbon fiber-reinforced filament for ballistic protection applications. This study expands on sandwich panel designs with woven Kevlar face sheets and investigates an optimal fiber reinforced filament core structure design. A unit cell workflow was developed in nTop to take advantage of its custom cell modeling and FEA capabilities. Unit cell types were simulated and tested from the hexagonal honeycomb, gyroid TPMS, and re-entrant auxetic cell families. Core structure thickness and cell size were additive manufacturing parameters that were varied to assess the …

Validation Of Mobile Devices In Arbitrary Locations Against Force Plate Standard For Balance Assessment, German J. Ellsworth

Master's Theses

With balance assessment being essential to the prediction of fall risk and detection and assessment of motor disorders, increasing clinical accessibility to objective balance metrics is essential. Work has been done validating center of mass (COM) acceleration metrics against well regarded force plate center of pressure (COP) position standards for mobile device data acquisition systems, but most research is restricted to devices being close to the COM or strapped in a harness configuration. Through the use of rigid body kinematics and the inverted pendulum model, this study develops novel methodology for calculating COM acceleration using mobile devices in arbitrary positions, …

Design And Implementation Of An Inverted Short Baseline Acoustic Positioning System, Jakob Frabosilio

Master's Theses

This document details the design, implementation, testing, and analysis of an inverted short baseline acoustic positioning system. The system presented here is an above-water, air-based prototype for an underwater acoustic positioning system; it is designed to determine the position of remotely-operated underwater vehicles (ROVs) and autonomous underwater vehicles (AUVs) in the global frame using a method that does not drift over time.

A ground-truth positioning system is constructed using a stacked hexapod platform actuator, which mimics the motion of an AUV and provides the true position of an ultrasonic microphone array. An ultrasonic transmitter sends a pulse of sound towards …

Slo Children’S Museum Music Education Exhibit, Charles Coffen, Madeline Carleton-Sniff, Yael Castillo, Anthony Ramos

Mechanical Engineering

The Children’s Museum in San Luis Obispo is a non-profit facility providing education to young children through interactive exhibits. The proposed project would address a basic introduction to musical theory through mechanical engineering principles. The target audience for this musical art installation would be young children, aged 5-10, who would be regularly interacting with this exhibit, as well as their parents, and the employees of the museum. The installation will educate children in basic musical understanding through interaction while still being engaging enough to hold their attention. This document describes the final concept design and various methods of verification in …

Modeling, Simulation, And Experimental Testing Of A Single-Legged Hopper, John Anthony Bennett

Master's Theses

Legged robots are well-suited for navigating unstructured terrain due to their ability to perform agile dynamic motions. Building on the efforts of Cal Poly's Legged Robotics Group, this project focuses on achieving stable forward hopping with a single legged robot.

A comprehensive model of leg hopping is formulated, with leg dynamics during flight and stance phases derived using Euler-Lagrange equations. During the stance phase, a spring-mass system models the leg-ground interaction. The touchdown and lift-off conditions are formulated mathematically, and state mappings between phases are determined via momentum conservation. A two-phase hybrid controller is designed, incorporating trajectory planning during flight …

Formula Integrated Monocoque Development, Hayden Wagner, Aaron Fang, Elijah Schulz, Carson Smith

Mechanical Engineering

Every year the Cal Poly Racing FSAE club set out to create two separate race cars to compete in the upcoming formula combustion and formula electric competitions. Both the combustion and electric formula cars operated on the same vehicle platform with the powertrain systems being the main difference between the two cars. Cal Poly Racing FSAE is the only school in California to run a full carbon fiber monocoque chassis, with each chassis design operating on a roughly four year design cycle. A new FSAE senior project team has set out to improve upon the previous chassis design as the …

A Screening Life Cycle Analysis Of One-Way And Reusable Crate Designs – Estimating Environmental Impacts Via Lca Software, Nicolas R. Corona

Master's Theses

A comparison analysis conducted via COMPASS life cycle analysis software has indicated that a one-way crate design, rather than a reusable crate design, is in fact the more environmentally friendly packaging system. These results can be interpreted differently, however, as the manufacturer of said crate designs must confirm what impact indicators they would like to reference as environmental goalposts. The conducted analysis provides insight into what the environmental impacts of each packaging system look like as packaging at all three system levels has been identified as a means of reducing environmental impacts globally. As such, the manufacturer of said crate …

Spring Rate Measurement Of A Pneumatic Mountain Bike Tire, Joseph D. Balderama, Alexandre Kachlakev, Duncan Wyke, Luki Rosen

Mechanical Engineering

The Final Design Review (FDR) presents a comprehensive overview of the spring rate measurement project for a pneumatic mountain bike tire. This report details the project's design, its implementation, and how it met all specified requirements. It also includes a discussion of the project's findings and recommendations for future work, assuming continuation of the project. The primary goal is to develop a device that allows professional race teams or experienced mountain bike riders to parameterize tires based on their spring rate in addition to internal pressure.

Since the Critical Design Review (CDR), the design has undergone significant changes due to …

Rapid Composter, Cate Seay, Clarisbet De Jesus, Lesley Milena Estrada, Reese Dennett

Mechanical Engineering

This Final Design Review documents the efforts of a team of mechanical engineering students from California Polytechnic State University, San Luis Obispo as they work towards completing their assigned senior design project. This team was tasked with designing and developing an onsite rapid composter for the Girl Scouts of California’s Central Coast. The selected design concept that will be explained focuses on creating a composter that is child-safe, portable, weatherproof, solar-powered, and requires minimal manual user input. This report will not only provide a detailed description of the chosen design but will also supply an extensive design justification. This mainly …

Cal Poly Bsae Brake Caliper, Carter Henry Foye, Benjamin Leistiko, Nathan Berger, Colin Williams

Mechanical Engineering

In the past, the Cal Poly Racing Baja SAE team has used off-the-shelf brake calipers for their vehicle. Off the-shelf calipers have been either oversized, resulting in a heavy and hard to package system, or undersized, resulting in an unreliable system that does not provide adequate braking power. The goal of this project was to provide a caliper that meets the requirements of Cal Poly’s Baja SAE team. Our final design consisted of a two piece CNC machined caliper that uses the complex piston seal geometry from an existing mountain bike brake caliper. Using an existing caliper as a reference …

Quarter Car Suspension Model, Jack Miller, Alexander Eckhardt, Jonathan Lam, Max Gardenswartz

Mechanical Engineering

Dr. Porumamilla, Professor of Mechanical Engineering at Cal Poly, needs a way to demonstrate the concept of base excitation to the mechanical engineering students in the Mechanical Vibrations (ME 318) Lab. A mass-spring-damper model represented by a quarter-car suspension has been selected to represent this concept. A team of four students was assigned to design such a model as a senior design project. This document will explain the testing procedures, how were the results, and if they achieved our requirements. Furthermore, the document will explain how we assemble our product and manufacturing steps. Additionally, Critical Design Report (CDR) design changes …

F56: Rocket Thrust Vector Control, Ethan Douglas Anderson, Yiming Trent Jia, Sahil Sampat

Mechanical Engineering

This Final Design Review (FDR) report compiles relevant information regarding the Rocket Thrust Vector Control senior project as sponsored by Ethan Anderson from Cal Poly Space Systems (CPSS). Documented in this report is our progress from the months following our Critical Design Review (CDR) completion. This consists of a brief overview of the design our thrust vector control (TVC) system and its subassemblies with design changes noted, a thorough walkthrough of our procurement, manufacturing, and assembly process for creating our verification prototype (including software), a breakdown of how we verified each of our specifications through inspection and testing and the …

Cal Poly Battle Bot (F41), Jyotaaver S. Nirula, Andrew D. Peterson, Johnathan W. Waldmire, Nathaniel Ab Davis

Mechanical Engineering

This senior project endeavored to design, construct, and optimize a 120lb robot combatant tailored for the competitive arena of combat robotics. The project is a collaborative effort between mechanical, computer, and electrical engineering students at Cal Poly, combining diverse expertise to achieve a unified goal. Our competition, RoboGames, was in April of this year in Northern California.

The mechanical engineering team assumed primary responsibility for the physical components of the battle bot, focusing on three pivotal components: a robust drivetrain, armor, and a highperformance vertical spinner. These elements constitute the foundation of the battle bot's offensive and defensive capabilities, crucial …

Non-Linear Modeling Of Hysteresis In Piezoelectric Actuated Cantilever Beam Using The Bouc-Wen Model, Andrew Donald Maas

Master's Theses

Piezoelectric actuators frequently exhibit a time-dependent behavioral phenomenon known as hysteresis, resulting in a lag in the deformation of the actuator compared to linear models. The presence of hysteresis complicates control systems involving piezoelectric actuators. However, traditional modeling methods for piezoelectric actuated smart structures often treat the piezoelectric patches as linear actuators without considering hysteresis, leading to suboptimal controller performance.

This thesis aims to establish a comprehensive model by integrating the Euler-Bernoulli beam bending model with the hysteresis dynamics induced by two opposing piezoelectric patches attached to a beam. A model expansion method is employed to transform the partial differential …