Applied Mechanics Commons^™

Elevate Hardcase, Caleb J. Bailey, Colby M. Cordoba, Marissa Mccleod, Shaan Sandhu

Mechanical Engineering

The Elevate Hardcase project developed a portable mechanical elevation system that allows users to access rugged hard cases at a comfortable working height without needing a separate table or placing the case on uneven ground. The design focuses on improving ergonomics, portability, stability, and quick setup for users in field environments such as photography, hunting, and maintenance. Through customer research, concept development, prototyping, analysis, and testing, the final system was designed to support a loaded hard case, provide height adjustability, remain stable on uneven terrain, and be deployed by a single user in under five minutes. The final prototype demonstrates …

Foldable Transfer Platform, Toby Sagi, Ashton Heiati, Triton Johnson, Zachary Denis

Mechanical Engineering

The report details the design and results of a Hoyer lift to transfer patients between wheelchairs and our sponsor's, Beacon VTC Santa Maria, vans. The lift disassembles into 3 main pieces, allowing the lift to be stored in the back of the van. The lift uses a hydraulic actuator to rotate the boom. We handed over our project to Beacon VTC Santa Maria for use in their facility!

Electronic Bike Chopper, Caleb S. Bermack, Joey Lederer, Ethan Dea, Evan Herrera, Fred Agregado

Mechanical Engineering

Our sponsor, David Royce, built an initial e-bike chopper prototype and desired an improved, next generation version. Our team designed and manufactured an electric bicycle to achieve the rugged visual style of a classic chopper motorcycle while improving stability and usability. The team built a functional E-Chopper prototype using a 4130 steel frame, custom dropouts, a long front fork, wide rear tire, ape-hanger handlebars, and prebuilt electric components such as the battery, hub motor, controller, throttle, and display. The design focused on reducing excess weight, improving frame rigidity, and meeting California e-bike regulations.

Me3328 Buckling Lab, Willem Bitterolf, Samantha Flores, Jacy Gonsalves, Brooke Thompson

Mechanical Engineering

The objective of this senior design project is to design and develop an instructional buckling apparatus (hereafter referred to as a “buckling tester”) to enhance student comprehension of column buckling behavior through direct experimental investigation. The apparatus is specifically intended to bridge the gap between theoretical predictions and observed physical response of structural column members subjected to axial compressive loading. In particular, the system will allow students to examine how column behavior transitions between Euler’s elastic buckling theory, which governs long, slender columns, and the Johnson parabolic formula, which more accurately describes intermediate and shorter columns influenced by material yielding. …

Me3328 Combined Loading Beam Bending Lab, Alejandro Islas, Viswesh Vancheeswaran, Owen Spencer, Henry Andrews

Mechanical Engineering

Serving as a new laboratory experiment for ME 3328 (Design for Strength & Stiffness), strain gauges were adhered, wired, and calibrated on a cantilever beam lab apparatus capable of undergoing pure bending, pure torsion, and combined bending.

Cal Poly Fluid Powered Vehicle Challenge 2025/2026, Ethan Malachi Nejame Zeiset, Christian Anthony Cuamani, Daniel Chacon-Bizarro, Marcus Minera, Bradley Hansell

Mechanical Engineering

In this Final Design Report, the Cal Poly Fluid Power Vehicle Challenge Contending Team competed in Sun Hydraulics’ 2026 Fluid Powered Vehicle Challenge. The objective of the competition is to expose college students to the fluid power sector, the “hidden giant” of the engineering industry. Specifically, student teams are tasked with the development of a human-powered, fluid-driven vehicle for use in various competitive settings. The team prioritized the optimization of an existing prototype for simplicity, ease of maintenance, and reliability during the competition. The existing prototype exhibited issues related to the main frame’s deflection under load, a lack of gear …

Multi-Ton Bin Transport Device, Cole Kramer, Ruth Stirrup, Fabian Ruiz, Daniel Ramirez

Mechanical Engineering

This project sought to solve a problem at the Water Resource Recovery Facility in San Luis Obispo with the transportation of multi-ton bins on-site. Their current solutions prove ineffective, as they damage their equipment and the concrete pad, as well as pose major safety risks to the operators moving these bins. The Facility requires the bin transport design to be low-cost, effective, and without risk of damage to the bins or surroundings, while maintaining the integrity of the bins. This project presents a conceptual design that is similar to a scissor lift, integrated into a trailer which will connect to …

Characteristic Stress And Strain Optimization Of Cardiovascular Catheters With Laser-Cut Hypotubes Using Finite Element Analysis, Kyle E. Hirth

Master's Theses

Cardiovascular catheter systems rely on laser-cut hypotubes to balance flexibility and structural integrity required for minimally invasive surgical procedures.  Optimizing these mechanical characteristics remains a significant challenge.  This study aims to investigate the influence of key laser-cut geometric parameters on the mechanical performance of hypotubes through finite element analysis.

Commercially representative laser-cut hypotubes were modeled and a finite element model was developed.   Geometric design parameters were varied across a design space consisting of pitch values ranging from 0.006 in. to 0.018 in. and cuts per revolution (CPR) ranging from 2.5 – 4.5.  For each pitch and CPR combination, loading stiffness …

Design And Development Of A 12-Degree-Of-Freedom Quadruped Robot, Kai De La Cruz

Master's Theses

This thesis presents the design, analysis, and experimental validation of a 12-degree-of-freedom (DOF) quadruped robot developed as a research platform for legged locomotion and control. The system builds upon the Cal Poly Legged Robotics Group’s prior 8-DOF quadruped, addressing key limitations in manipulability, load distribution, and mechanical robustness by introducing a 3-DOF leg architecture.

The mechanical design emphasizes lightweight construction, structural integrity, and modularity to support future research extensions. Static and dynamic loading models were developed to inform component sizing and material selection. A carbon-fiber chassis and redesigned leg assemblies were fabricated and validated through finite element analysis and physical …

Lidss Raft Battery Pack Integration, Jack Maxwell, Vincent Stevens, Matthew Hoodmaker, Colin Flanders

Mechanical Engineering

Lawrence Livermore National Laboratory is a critical member of the United States Department of Defense. Their Independent Diagnostics Scoring System (LIDSS) uses rafts that operate in the ocean to collect missile test data. Several times a year, the United States will test their Inter-Continental Ballistic Missiles by launching them into the ocean near the Marshall Islands. This is where the LIDSS rafts collect their test data. Our project was centered around re-designing the battery pack used by the rafts. The current battery pack design experiences water ingress problems and is difficult to access. Our re-designed battery pack is waterproof to …

Trailer Transport System For Multi-Ton Bins, Joanna Lizbeth Bendy, Kevin Matthew Creel, Annelise Vaara Cuneo, Hugo Alonso Valdez

Mechanical Engineering

This project aimed to improve the process of transporting 10,000-pound industrial waste bins. The current method for relocating these bins poses safety risks and requires significant manual effort. This project presents a conceptual solution that enables a single operator to efficiently and safely move roll-off bins using a custom-designed trailer system. The design incorporates three main subsystems: a trailer frame, an integrated winch system, and an off-the-market puller device to guide and secure the bin during transport. Two scaled proof-of-concept prototypes were fabricated to evaluate key aspects of the system's functionality. Testing and analysis suggested that the system is viable …

Large Backflow Check Valve Life Cycle Test Stand, Colin Bentley, Christopher Carloni, Ethan Gray, Luke Romanini

Mechanical Engineering

Backflow preventers are plumbing devices containing internal check valves used to prevent cross-contamination between downstream contaminants and potable water supply. Zurn Wilkins needs a life cycle test stand to mechanically force open check valves submerged in contaminated water and verify check performance. The stand needs to be modular to work with a range of check types and sizes.

Zurn Wilkins is the primary stakeholder for this project. Secondary stakeholders include commercial and residential building owners, contractors, and water utility companies, who rely on their products for safe and efficient water management. The team for this project consists of four Cal …

Effect Of Manufacturing And Machining Process On Recycled Composite Connecting Rods Under Tension And Compression, Walter W. Oppelt

Master's Theses

Carbon fiber reinforced polymer (CFRP) is an engineering material renowned for its high-strength and low-density material properties. Such properties make CFRPs especially useful for applications across many industries, including aerospace, automotive, marine, sporting goods, oil and gas, and more. However, with such favorable material properties comes the cost of high energy usage required to produce raw carbon fiber. Recycled carbon fiber (rCF) has emerged as a promising alternative, offering a significant reduction in energy usage. This research explores the viability of applying recycled CFRPs to internal combustion engines to both reduce energy costs during manufacturing and while in use. Mechanical …

Model-Based Design Of Compressed Lithium-Metal Pouch Cell Battery Modules For Evtol Applications, Scott J. Stirling

Master's Theses

Batteries with higher specific energy and power are essential for extending the range and performance of electric vertical takeoff and landing aircraft (eVTOLs). Anode-free lithium-metal pouch cells offer strong potential at the cell-level but require high compressive pressures to enhance cycle life and discharge performance. These pressures necessitate heavier structural components, reducing packaging efficiency at the module level.

To evaluate this tradeoff, a full-factorial enumeration model was developed to explore viable module designs within a constrained packaging volume. The model scales subsystem masses, enforces design rules and material limits, and accounts for large (~20%) cell thickness changes during cycling.

Results …

Adjustable Dynamometer Motor Mount, Garrett Carson Ng, Elijah Siegel Reuven, Ethan Fong, Daniel Larimer

Mechanical Engineering

The Cal Poly Electrical Engineering Department and sponsor Dr. Dolan needs a manufacturable motor fixture that securely aligns motors of various sizes with dynamometers. Previous lab motor fixtures could not accommodate motors of different sizes, making precise alignment between motors and dynamometers time-consuming and unreliable. Our team developed a modular, manufacturable fixture capable of aligning various motor sizes quickly, accurately, and securely, enhancing lab consistency and usability.

Cruising On The Beach (Cob), Juan Diego Molina Ii, Ashley Kianna Burga

Biomedical Engineering

This report details the design and development process of Cruising on the Beach (COB), a modular motorized wheelchair intended to improve beach accessibility for high school students with mobility impairments. The project aimed to create an affordable, portable, and sand-capable device using balloon wheels, an adjustable control panel, and a customizable base. Extensive background research, market analysis, design modeling, and test plans were completed. However, final fabrication was not achieved due to financial constraints and limited access to industrial machining tools needed for custom metal components. Despite these setbacks, the project delivered a robust conceptual design and a fully …

Helical Products Parts Display Stand, Binh Nguyen, Emily Yuan Mendyke, Zoe Porter

Mechanical Engineering

Helical Products needs a new product display stand that will demonstrate their custom springs, couplings, and u-joints. Their current display stand, a marble run contraption, is large, loud, and difficult to transport, so they would like the new stand to remedy these issues. The goal of this senior project is to create a display stand that captures the attention of their customers with dynamic product demonstrations while addressing the issues outlined above.

The new display stand is also a marble run contraption, but instead of being almost 4 feet tall and 3 feet long, it is 23” tall, 26.25” long, …

Development Of Planetary Drive System For Formula Sae Electric Race Car, Brian Wong, Bradley Maruoka, Joshua Charles Fine, Madison Kai

Mechanical Engineering

Hub motors are compact electric motors mounted directly on each outboard wheel hub. Utilized in Formula SAE and Formula Student vehicles, this configuration offers several advantages over traditional drivetrains, including packaging optimization within the chassis, vehicle traction, and improved efficiency. Although hub motors are not yet common in 4WD vehicles, they are being explored for use in EVs and may become more common in the future. Every year, Cal Poly Racing FSAE designs and builds a formula-style race car. To improve drivetrain performance, the team is investigating the achievability of a hub motor 4WD drivetrain, requiring extensive research, development, and …

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 …

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 …

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 …

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 …

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, …

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 …

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 …

Design And Implementation Of A Vision-Based Deep-Learning Protocol For Kinematic Feature Extraction With Application To Stroke Rehabilitation, Juan Diego Luna Inga

Master's Theses

Stroke is a leading cause of long-term disability, affecting thousands of individuals annually and significantly impairing their mobility, independence, and quality of life. Traditional methods for assessing motor impairments are often costly and invasive, creating substantial barriers to effective rehabilitation. This thesis explores the use of DeepLabCut (DLC), a deep-learning-based pose estimation tool, to extract clinically meaningful kinematic features from video data of stroke survivors with upper-extremity (UE) impairments.

To conduct this investigation, a specialized protocol was developed to tailor DLC for analyzing movements characteristic of UE impairments in stroke survivors. This protocol was validated through comparative analysis using peak …

Liftwalker, Kai A. De La Cruz, Lexie Caterine, Adam Monroe, Jame Whealan

Mechanical Engineering

The LiftWalker’s purpose is to lift users with degenerative diseases from a seated to standing position and support them as they practice the motion of walking as a form of physical therapy. The current LiftWalker is upward of $5,000 so we redesigned the LiftWalker to be more accessible around the world. This meant using affordable and accessible materials and manufacturing processes. To achieve this, we made our design mostly out of bike parts and off-the-shelf components. When it came to the lift system, we found that to maintain a safe and comfortable design it was best to purchase a trailer …

Pitot Tube Test Bench, Jesus Perez, Zachary Owen, Adrian Lopez

Mechanical Engineering

This Final Design Review documents the senior design project carried out by a team of Mechanical Engineering students attending California Polytechnic State University, San Luis Obispo for Roger Benham, and his company Leak Control Services Inc. The requirement was to design, build, and validate the performance of a test fixture that quantifies the performance characteristics of flow rate and pressure drop of different pitot tube designs to be used in a chemical dispensing application for Mr. Benham. This document includes relevant background research on the need for the fixture as well as relevant technical research. This document also contains objectives …

Deep Ocean Vehicle Applications And Modifications, Nichole "Nikki" T. Arm

Master's Theses

This project had two primary goals: (1) to explore opportunities to further a deep-ocean vehicle’s reach using alternative pressure spheres, and (2) to implement an existing deep-ocean vehicle (lander) in active scientific research.

I gained a greater understanding of the limitations and design choices made for existing pressure spheres using Finite Element Analysis (FEA). My simplified FEA model predicted sphere failure for the existing 30% Fiber Glass 70% Nylon injection molded spheres at an external pressure of 3,954psi or 2,690m ocean-depth (only a 7.38% error compared to the tested minimum failure depth), so I determined it a valid model. I …

Additive Manufacturing And Characterization Of Auxetic Structures, Jayesh P. Moore, Stephanie R. Ruzicka

College of Engineering Summer Undergraduate Research Program

An auxetic structure is an arrangement of unit cells that under a uniaxial load experiences expansion in both the longitudinal and transverse directions, resulting in a negative Poisson’s ratio (NPR). Research in auxetics has led to new insights into how non-linear mechanical reactions can be applied to various engineering fields. This project utilized stereolithography (SLA) 3D printing to manufacture auxetic test specimens to analyze of geometry-driven NPRs. With the distinctive mechanical properties of auxetic structures and vast applications, the future of product development of these geometries seems promising.