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Northrop Grumman Collaboration Project, Nikkia Psomas-Sheridan, Santiago Robles, Ben Elkayam, Benjamin Ulfhake

Mechanical Engineering

The Northrop Grumman Collaboration Project (NGCP) is a collaborative club project sponsored by Northrop Grumman for the students of Cal Poly San Luis Obispo (CPSLO) and Cal Poly Pomona (CPP) to create a fleet of vehicles to aid in the simulated rescue of stranded hiker. The CPSLO club is responsible for delivering an autonomous flight vehicle that can suppress a fire and retrieve a payload. Mechanical Design Team of the CPSLO team was responsible for the design of the frame, electronics housing, and payload and fire suppression systems.

Northrop Grumman Collaboration Project, Nikkia Rae Psomas-Sheridan, Santiago Robles, Ben Elkayam, Benjamin Ulfhake

Mechanical Engineering

The Northrop Grumman Collaboration Project (NGCP) is a collaborative club project sponsored by Northrop Grumman for the students of Cal Poly San Luis Obispo (CPSLO) and Cal Poly Pomona (CPP) to create a fleet of vehicles to aid in the simulated rescue of stranded hiker. The CPSLO club is responsible for delivering an autonomous flight vehicle that can suppress a fire and retrieve a payload. Mechanical Design Team of the CPSLO team was responsible for the design of the frame, electronics housing, and payload and fire suppression systems.

Investigation Of The Effects Of Cladding Layers On Longitudinal And Transverse Mechanical Properties In Composite Laminates, Rachel Potratz, Tiffany Foo, Joseph Kamlet

Materials Engineering

The addition of cladding layers to composite laminates is used in industry to improve bond adhesion and the ease of manufacturing. However, there is no public data on the effects of cladding layers on the mechanical properties of composite components. To directly observe how cladding layers affect mechanical properties, four laminates with zero, one, two, and three cladding layers of twill fabric were added symmetrically to a biased core. The mechanical testing performed was tensile, short beam strength, and compression testing in the longitudinal and transverse directions. The measured strengths were related to the longitudinal properties of the core, and …

Non-Destructive Material Analysis Of Metals And Composites Via Thermography, Jonathan R. Doubt, James L. Chapman

Materials Engineering

The Naval Surface Warfare Center, Port Hueneme Division, is interested in the development of non-destructive damage assessment of shipboard materials via drones at distance. Long Pulsed Thermography (LPT), a method of non-destructive evaluation, was investigated as a possible method for detecting damage in metals (5005h24 Al alloy and 1008 carbon steel) and composites (aramid fiber honeycomb sandwich structure) at distances from 0.5 m to 3.0 m. LPT was conducted using two 1000 W can lights to heat the samples, and a FLIR E8-XT thermal camera. The images were then analyzed using ImageJ software to determine if damage could be detected …

Tensile Testing Environmental Chamber – Structural, Michael Ingel, Erik Soldenwagner, Austin Marshall, Lauren Schirle

Mechanical Engineering

Environmental chambers for tensile testing machines are used to study how a multitude of materials behave in extreme temperatures. These chambers provide the necessary information to innovate cutting edge technology for materials in fields such as aerospace. These chambers are often heavy and expensive requiring a significant amount of time and money just in the installation process alone. This report will serve to outline and define the design and fabrication of an environmental chamber, conducted by a team of four senior mechanical engineering students at California Polytechnic State University, San Luis Obispo. The goals of the project include a low-weight …

Enduro Campers, Ryan J. Shomsky, Alexander W. Horst, Kevin S. Pickering, Jackson L. Aplanalp, Luke Arana, Will Firestone

Mechanical Engineering

The Enduro Campers senior project team (Formerly known as Lobo Campers senior project team) was recruited by Mr. Leif Stein to assist in the design, manufacturing, and testing of the materials and components of his company’s expedition box camper. The two main focuses of the project, divided into two sub-teams, were on the testing and manufacturing process of the materials used in the camper, and on the design and analysis of the camper’s access door, step box, and other subsystems.

The focus of the materials analysis and manufacturing team was based around the design parameter to use composite sandwich panels …

Study Of Permeability Testing Methods For Composite Laminates, Thomas S. Busse, Giannina Marie M. Yu

Materials Engineering

Permeability measurements are strong indicators of the effectiveness of evacuation channels within a composite prepreg. The effectiveness of these evacuation channels directly relates to the void content within a processed composite laminate. The goal of Toray Advanced Composites was to compare two permeability tests and determine which one was more reliable, accurate, and economical. The first permeability test method was the Cirrus method, designed by Cirrus Aircraft, a customer of Toray Advanced Composites. The second test was ASTM D8132, the standard method for permeability testing. Additionally, Toray sought to investigate the effect out-time had on the permeability of three different …

Composite Liftwalker For Shurouq, Daniel Martinez, Robert Boyd, Vikram Thridandam, Madeline Faase

Mechanical Engineering

The following document describes the scope of our project and the methods we have deployed in designing and manufacturing a personalized composite LiftWalker for a young woman in Egypt named Shurouq. Our objective is to design a lightweight and durable LiftWalker to improve upon the current product of our project sponsor, Charlie Gutierrez. To accommodate Shurouq’s physical disabilities as well as the limits of transporting the device to her by plane, our team will need to alter the current product’s dimensions, materials, and structure. Through researching similar products and interviewing potential customers, we have compiled engineering specifications to guide the …

Cal Poly Prove Lab Endurance Car Composite Body Paneling Design, Emma Wheelock, Sarah Rutland, Noah Fisher, Brian Menard

Mechanical Engineering

The Cal Poly Prototype Vehicles Laboratory (PROVE Lab) needs a body paneling design for their Endurance Car aeroshell which optimizes strength, weight and accessibility while minimizing complexity. Additionally, a low-complexity, accurate manufacturing process for the PROVE Lab Endurance Car aeroshell needs to be developed. PROVE Lab designed the shape of the aeroshell. The aeroshell will serve to reduce the aerodynamic drag on the car at high speed, and is not a structural component of the car. Due to the high-strength and lightweight nature of composites, PROVE Lab requests the senior project team investigate using composites for automotive body paneling applications. …

Numerical Methods For Predicting The Dynamic Crushing Response And Energy Absorption Of Composite Aluminum Honeycomb Sandwich Structures, Cody R. Volk

Master's Theses

Edgewise crushing responses of composite aluminum honeycomb sandwich structures were predicted using finite element analysis (FEA) software LS-DYNA by modeling the honeycomb as a material with anisotropic properties. The goal of the project was to develop a process for modeling the sandwich structure to rapidly iterate possible solutions for a safer workstation train table. Current workstation tables are too rigid and may cause injury or death in a head-on collision. Experimental compression tests were used to calibrate the aluminum honeycomb core with material type 26 (MAT 26, honeycomb). A published composite tensile test was used to validate the use of …

Adaptive Paddle Board, Alexander Holthaus, Alexander Holthaus, Garrett Holmes, Garett Jones

Mechanical Engineering

This Final Design Review (FDR) document outlines the Adaptive Paddle Board senior project, done by four Mechanical Engineering Students at California Polytechnic State University and provides detail on the project and what the team has accomplished. The goal was to create a universally adaptive paddle board that can be used by the Central California Adaptive Sports Center for a wide range of persons with disabilities. This document highlights current research from patents and existing products, details regarding customer specifications, results from concept generation, the manufacturing and testing that went into the final design, and the process taken to get there. …

C6 Wheels, Samuel L. Pizot, Luke Martin, Josh Warner, Jonah Levis

Mechanical Engineering

This document details the C6 Wheels project being undertaken for senior design. The objective is to design and manufacture carbon fiber reinforced polymer wheels for the Cal Poly Formula Society of Automotive Engineers (FSAE) team. The wheel shells will be used on FSAE’s competition vehicles. FSAE requested the wheels to improve the handling characteristics of their vehicles by reducing the unsprung and rotational mass. They have attempted carbon fiber wheels previously but have not yet run any on their vehicles. FSAE specifically proposed the design of carbon fiber shells with an aluminum center as opposed to full carbon fiber wheels …

Investigation Of Design, Manufacture, Analysis, And Test Of A Composite Connecting Rod Under Compression, Thomas Juhl Rohrbach

Master's Theses

Composite materials hold great potential for the replacement of traditional materials in machines utilized on a daily basis. One such example is within an engine block assembly where massive components inherently reduce the efficiency of the system they constitute. By replacing metal elements such as connecting rods, cylinder caps, or a crank shaft with composite alternatives, a significant increase in performance may be achieved with respect to mechanical strength, thermal stability, and durability, while also reducing mass. Exploration of this technology applied to a connecting rod geometry was investigated through a combination of process development, manufacturing, numerical analysis and testing. …

Prove Endurance Car Front Suspension, Lauren A. Williams, Logan Simon, Justine G. Kwan

Mechanical Engineering

This document details the collaborative Mechanical Engineering Senior Project with Cal Poly PROVE Lab on PROVE Lab’s Project 2; an electric vehicle designed to travel 1000 miles on a single charge. Logan Simon, Justine Kwan, and Lauren Williams are given the challenge of designing an innovative proof of concept front suspension suspension for this vehicle.

After detailed research of new suspension systems, it was determined that the innovative nature could be in the form of unique manufacturing methods, materials use, or mechanical design. At this point in time, this vehicle is a purely conceptual design with no concrete requirements. Therefore …

A Comparison Study Of Composite Laminated Plates With Holes Under Tension, Joun S. Kim

Master's Theses

A Comparison Study of Composite Laminated Plates with Holes under Tension

A study was conducted to quantify the accuracy of numerical approximations to deem sufficiency in validating structural composite design, thus minimizing, or even eliminating the need for experimental test. Error values for stress and strain were compared between Finite Element Analysis (FEA) and analytical (Classical Laminated Plate Theory), and FEA and experimental tensile test for two composite plate designs under tension: a cross-ply composite plate design of [(0/90)4]s, and a quasi-isotropic layup design of [02/+45/-45/902]s, each with a single, centered hole of 1/8” diameter, and 1/4" diameter (four sets …

Drawing And Twisting Of Graphene Fibers, Gregory T. Lane, Robert J. Sekerak, Isaias Diaz

Mechanical Engineering

The aim of this project was to develop a more automated process for drawing and twisting of graphene fibers than was currently in place. This was implemented by having two chemical baths with variable speed rollers at either end, and intermediate roller to spool fiber between stages, and a twisting cylinder with integral spool to twist the fiber as it is collected. The goal was to have this first iteration deliver a working prototype, however due to manufacturing delays and timing constraints, that will be missed. A second follow-on project would be able to continue the work presented here and …

The Effect Of Biocomposite Material In A Composite Structure Under Compression Loading, Benjamin Andrew Sweeney

Master's Theses

While composite structures exhibit exceptional strength and weight saving possibilities for engineering applications, sometimes their overall cost and/or material performance can limit their usage when compared to conventional structural materials. Meanwhile ‘biocomposites’, composite structures consisting of natural fibers (i.e. bamboo fibers), display higher cost efficiency and unique structural benefits such as ‘sustainability’. This analysis will determine if the integration of these two different types of composites are beneficial to the overall structure. Specifically, the structure will consist of a one internal bamboo veneer biocomposite ply; and two external carbon fiber weave composite plies surrounding the bamboo biocomposite. To acquire results …

Fiber Length Attrition In Additive Manufacturing, Michael Chapiro

Materials Engineering

Chopped carbon fibers are used as reinforcements in thermoplastics, but the viscous shear forces that arise in melt-processing reduces the fiber length well below its critical length resulting in only moderate strength and stiffness gains compared to the neat resin. This research project aimed to experimentally determine the effect of the melt–flow portion of a single-screw- extrusion process on carbon fiber length attrition in isolation from the immediately preceding screw–plastication step that is responsible for most of the heat needed for melting. Carbon fibers with an initial length of 2 mm were stirred into 5,000 centipoise and 10,000 centipoise silicone …

Finite Element Modeling Of Delamination Damage In Carbon Fiber Laminates Subject To Low-Velocity Impact And Comparison With Experimental Impact Tests Using Nondestructive Vibrothermography Evaluation, George Rodriguez Iv

Master's Theses

Carbon fiber reinforced composites are utilized in many design applications where high strength, low weight, and/or high stiffness are required. While composite materials can provide high strength and stiffness-to-weight ratios, they are also more complicated to analyze due to their inhomogeneous nature. One important failure mode of composite structures is delamination. This failure mode is common when composite laminates are subject to impact loading.

Various finite element methods for analyzing delamination exist. In this research, a modeling strategy based on contact tiebreak definitions in LS-DYNA^®was used. A finite element model of a low-velocity impact event was created to …

Effect Of Low Velocity Impact On The Vibrational Behavior Of A Composite Wing, Richard M. De Luna

Master's Theses

Impact strength is one of the most important structural properties for a designer to consider, but it is often the most difficult to quantify or measure. A major concern for composite structures in the field is the effect of foreign objects striking composites because the damage is often undetectable by visual inspection. The objective for this study was to determine the effectiveness of using dynamic testing to identify the existence of damage in a small scale composite wing design. Four different impact locations were tested with three specimens per location for a total of 12 wings manufactured. The different impact …

An Investigation Into The Properties And Fabrication Methods Of Thermoplastic Composites, Ann E. Livingston-Peters

Master's Theses

As applications for thermoplastic composites increase, the understanding of their properties become more important. Fabrication methods for thermoplastic composites continually improve to match designs specifications. These advanced thermoplastics have begun to show an improvement in mechanical properties over those found in thermoset composites commonly used in industry. Polyaryletherketones (PEK) have high service temperatures, good mechanical properties, and improved processing capabilities compared to thermoplastics used in the past making them important to the aerospace industry. The wide range of types of PEK make them suitable for a variety of applications, but selection of specific chemistries, processing parameters, and composite stack-ups determine …

Low-Cost Strider For Guatemala, Nicole Catherine Cooper, Gonzalo Hernandez, Jared W. Tower

Mechanical Engineering

The purpose of this project was to create a strider, a type of standing rehabilitation device, for children in developing countries who have trouble walking and supporting their full body weight. The project was initially brought to us by Cal Poly professor Brian Self, who had visited a clinic in San Marcos and determined that there were children there who had difficulties with walking and were a need for a rehabilitation device. The team discussed the problem with Dr. Self, Matt Robinson (a local San Luis Obispo prosthetist), and Cal Poly physics professor Pete Schwartz, all of whom had visited …

Development Of A Finite Element Model For Predicting The Impact Energy Absorbing Performance Of A Composite Structure, Matthew Lowell Roberts

Master's Theses

Because of their high strength-to-weight ratio, Fiber Reinforced Composite (FRC) materials are well suited for use in high performance racing applications where weight must be kept to a minimum. Formula SAE (FSAE) race cars are designed and built by college students, roughly following the model of a scaled down Formula One car. Strict regulations are placed on specific components of the car in the interest of equalizing competition and ensuring the safety of the drivers. Students are required to construct a survival cell (the chassis), which can resist large amounts of energy in the event of a crash, with an …

Simplifying The Testing And Calculation Of Fracture Toughness Of Thermoplastic And Thermoset Matrix Composite Materials, James Shedden

Materials Engineering

Fracture toughness, or the ability of a material to resist fast fracture by crack propagation is an important property in the use of composite materials for structural designs. Other mechanical tests such as tensile, flexure, and compression are more established and practical than testing fracture toughness. Fracture toughness testing is less commonly used because it requires specific specimens and non-conventional test methods. In composite materials specifically, delamination of the plies of materials is tested for G_IC and G_IIC values to find the critical strain energy release rate of the two types of fracture modes. The common two tests …

Drape Forming Machine, Adam Johnson, Will Schlosser, Brian Miller

Mechanical Engineering

The goal of this project was to build a prototype machine that formed multiple sheets of debulked pre-preg OOA carbon fiber into a 2-foot long trapezoidal shape. The machine was required to do this process semi-automatically.

Design Allowables Re-Evaluation Of Ten Composite Materials; Mechanical Testing And Porosity Examination Of M55j Fabric Coupons, Andrew Quayle

Materials Engineering

The design allowables for ten carbon fiber/cyanate ester composites used by Space Systems/Loral for satellite structures were recalculated. This recalculation is done in order to incorporate a growing pool of test data. B-Bases for tensile, compressive, and short beam shear strength (SBS) were generated. Means were calculated for combined modulus (an average of tensile and compressive moduli). Compressive strength B-Bases were higher than current B-Bases for nine of the ten materials, ranging from 27% to 44%. Tensile strength increases ranged from 1% to 18%. SBS changes were mixed, ranging from -39% to +22%. K13D2U tape was the only material which …

Wolfpack Gear Inc. Composite Frame Firefighter Backpack, Gabriel Mountjoy, Blair Ridings, Carl Drummond Buchenroth

Mechanical Engineering

No abstract provided.

The Effect Of A Low-Velocity Impact On The Flexural Strength And Dynamic Response Of Composite Sandwiches With Damage Arrestment Devices, Kodi A. Rider

Master's Theses

Impact strength is one of the most important structural properties for a designer to consider, but is often the most difficult to quantify or measure. A constant concern in the field of composites is the effect of foreign object impact damage because it is often undetectable by visual inspection. An impact can create interlaminar damage that often results in severe reductions in strength and instability of the structure. The main objective of this study is to determine the effectiveness of a damage arrestment device (DAD) on the mechanical behavior of composite sandwiches, following a low-velocity impact. A 7.56-lb_f crosshead …

Finite Element Modeling Of Ballistic Impact On A Glass Fiber Composite Armor, Dan M. Davis

Master's Theses

Finite Element Modeling of Ballistic Impact on a Glass Fiber Composite Armor

Dan Davis

Experiments measuring the ballistic performance of a commercially available fiberglass armor plate were used to guide the development of constitutive laws for a finite element model of the impact. The test samples are commercially available armor panels, made from E-glass fiber reinforced polyester rated to NIJ level III. Quasi-static tensile tests were used to establish material properties of the test panels. These properties were then used to create models in the explicit finite element code LSDYNA.

Ballistic impact testing of the panels was conducted using a …

Modal Analysis Of Composite Structures With Damping Material, Kellie Michelle Tremaine

Master's Theses

The purpose of this study is to develop an analytical solution for modal analysis of actively damped orthotropic composite plates in bending and to verify it with experimental analysis.

The analytical modal analysis solution for composite plate dynamics is derived using Euler theory. This analysis applies to structures with orthotropic lamina of uniform material properties at any lamination angle. The bending-extensional coupling can be neglected for plates that are symmetric or approximately symmetric, which allows an exact solution for natural frequency and mode shape to be obtained. An exact solution can be found for natural vibration and in general.

The …