Engineering Commons^™

Effects Of Composition And Solid Solution Strengthening On The Compression Strength Of Iron-Based Hardfacing Alloys, Tyler Wiggins, Samuel Garrison-Terry

Materials Engineering

Three iron-based hardfacing alloys were fabricated to have a tungsten strengthened matrix with varying compositions of 10-15, 20, and 30 wt% tungsten/chrome boride content. The fourth sample was fabricated to have a molybdenum solid solution strengthened matrix with 10-15 wt% W/Cr Boride content. This project focuses on the compressive strength of iron-based hardfacing alloys. Preliminary compression tests with Scoperta iron-based hardfacing alloys showed a need for sample dimension reduction due to compressive loads that could not be met by a 50 kN maximum capacity mechanical testing system. The preliminary tests showed compressive strengths exceeding 2340 MPa. Samples of the current …

Electrochemical Testing Of Aluminum-Lithium Alloys 2050, 2195, And The Current Aerospace Industry Standard 7075 To Measure The Galvanic Corrosion Behavior With Ti-6al-4v, Trent Duncan, Kevin Knight

Materials Engineering

This project aimed to characterize the electrochemical behavior of four different aluminum alloys, and determine how much galvanic corrosion would occur when each alloy was coupled to Ti-6Al-4V. The particular alloys tested were 2050-T3, 2050-T852, 2195-T852, and 7075-T7352. These alloys were tested to determine the effects of aging, and adding lithium, to the corrosion behavior of aluminum alloys. Potentiodynamic polarization curves were generated using the Parstat 2273 potentiostat in accordance with ASTM standard G5, and corrosion analysis software was used to produce Tafel fit lines, which determined the open circuit potential (E_corr) of each sample. Nine tests were …

Measuring And Increasing The Suspension Time Of Lanthanide Oxysulfide Particles With Modifiers Via Fluorescence For Use In Anti-Counterfeiting Applications, Joe Dei Rossi, Tyler Dinslage, Tyler Schelling

Materials Engineering

No abstract provided.

Mechanical Testing Of Multi-Construction Composite Tubes For Use In Fly Fishing Rods, Macormik Hopen

Materials Engineering

A testing protocol was established for measuring the flexure properties of thin-walled tubes constructed of a composite mixture of glass and carbon fibers and epoxy resin for use in Fly Fishing rods. Standard three point bend tests were conducted in accordance with ASTM standard D7329-13 with a span length of six inches. All samples were of the sample length and diameter, allowing direct comparison of the maximum loads reached before failure, which are directly indicative of the Modulus of Rupture (MOR). Two constructions were tested both containing the same unidirectional fiber but with different support structure. These tubes were tested …

Molecular Dynamics Investigation Of The Arabinan-Cellulose Interface For Cellulose Nanocomposite Applications, Luke Thornley

Materials Engineering

Atom level computer simulations of the arabinan and cellulose interface were performed to better understand the mechanisms that give arabinan-cellulose composites (ArCCs) their strength with the goal to improve man-made ArCCs. The molecular dynamics (MD) software LAMMPS was used in conjunction with the ReaxFF/c force field to model the bond between cellulose and arabinan. A cellulose nanocrystal with dimensions 51 x 32 x 8 Å was minimized with various weight percent of water, 0%, 3%, 5%, 8%, 10%, and 12%. After the system was equilibrated for at least 100,000 femtoseconds, an arabinan molecule composed of 8 arabinose rings was added …

Characterization Of Laser Deposited Ti-6al-4v To Nb Gradient Alloys, Clincy Cheung

Materials Engineering

An alloy was fabricated with Ti-6Al-4V and Nb powder using laser deposition (LD) to form a compositional gradient. The gradient was deposited, starting with Ti-6Al-4V powder, onto a forged Ti-6Al-4V substrate in an Argon environment. Niobium (Nb) composition increased by 4-at.% with each layer deposited until the composition reached 100-at.% Nb. This process yielded steep thermal gradients and affected the microstructure and mechanical properties across the compositional gradient. To observe the microstructural changes in the alloy, an etched gradient was viewed with optical microscopy at 1000x, where the grain structure was observed to be an acicular α phase at 100-at.% …

Comparisons Of Measurement Results As Constraints On Accuracies Of Measuring Instruments: When Can We Determine The Accuracies From These Constraints?, Christian Servin, Vladik Kreinovich

Departmental Technical Reports (CS)

For a measuring instrument, a usual way to find the probability distribution of its measurement errors is to compare its results with the results of measuring the same quantity with a much more accurate instrument. But what if we are interested in estimating the measurement accuracy of a state-of-the-art measuring instrument, for which no more accurate instrument is possible? In this paper, we show that while in general, such estimation is not possible; however, can uniquely determine the corresponding probability distributions if we have several state-of-the-art measuring instruments, and for one of them, the corresponding probability distribution is symmetric.

Non-Wetting Surface-Driven High-Aspect-Ratio Crystalline Grain Growth For Efficient Hybrid Perovskite Solar Cells, Cheng Bi, Qi Wang, Yongbo Yuan, Zhengguo Xiao, Jinsong Huang

Department of Mechanical and Materials Engineering: Faculty Publications

Large-aspect-ratio grains are needed in polycrystalline thin-film solar cells for reduced charge recombination at grain boundaries; however, the grain size in organolead trihalide perovskite (OTP) films is generally limited by the film thickness. Here we report the growth of OTP grains with high average aspect ratio of 2.3–7.9 on a wide range of non-wetting hole transport layers (HTLs), which increase nucleus spacing by suppressing heterogeneous nucleation and facilitate grain boundary migration in grain growth by imposing less drag force. The reduced grain boundary area and improved crystallinity dramatically reduce the charge recombination in OTP thin films to the level in …

Custom Keys: Numeric Keypad Server-Client Android App, Cameron Hom

Computer Science and Software Engineering

Custom Keys is an app that consists of a server and an app which communicate through the network. This project explored a way to improve numeric keystroke input for users who do not have numeric keypads on their laptops or computers. I discuss many features and designs I used in Custom Keys to create the app and server. I also discuss some of the drawbacks to the design. Custom Keys was successfully created but more testing and research is needed to determine if it improves individual numeric keystroke's per minute.

Homogeneous Spiking Neuromorphic System For Real-World Pattern Recognition, Xinyu Wu, Vishal Saxena, Kehan Zhu

Electrical and Computer Engineering Faculty Publications and Presentations

A neuromorphic chip that combines CMOS analog spiking neurons and memristive synapses offers a promising solution to brain-inspired computing, as it can provide massive neural network parallelism and density. Previous hybrid analog CMOS-memristor approaches required extensive CMOS circuitry for training, and thus eliminated most of the density advantages gained by the adoption of memristor synapses. Further, they used different waveforms for pre and post-synaptic spikes that added undesirable circuit overhead. Here we describe a hardware architecture that can feature a large number of memristor synapses to learn real-world patterns. We present a versatile CMOS neuron that combines integrate-and-fire behavior, drives …

Customer Tracking Through An Affordable Consumer Device Array, Daniel Nishi

Computer Science and Software Engineering

Commercial person tracking systems that use wifi packet analysis is currently very costly. In order to reduce the barrier of entry and allow small businesses to reap the benefits of indoor trilateration systems and monitor consumer traffic patterns, I am building out a system that will run on low-cost hardware and be deployable without a monthly service fee. By using consumer hardware, we are able to collect and analyze wifi management packets from smartphone sources and use it to extract actionable business information.

Cp Maps – An Interactive Cal Poly Map Ios Application, Brian Fung, Carl Lind Iii

Computer Science and Software Engineering

According to Forbes magazine, Cal Poly ranks No. 9 among Califor- nia’s public universities and is the top-ranked California State University for this past year[7]. More than 55,000 undergraduates seek admission for Fall 2015[11]. These visiting students and their families and as well as 20,000 cur- rent students, faculty and staff need an convenient way of navigating around campus[8]. Our iOS app—CP Maps—was built from the ground up to address the difficulty of navigating around campus.

Enterprise Smart Outlet - Ios Application, Riley Mcgovern

Computer Science and Software Engineering

The Enterprise Smart Outlet is a system made up of a smart outlet, a Node.js server, and a companion iOS application. It builds on the already existing market of smart power outlets and aims to bring that type of functionality fully scaled up to the enterprise level. The smart outlet connects to the Node.js server and sends its power readings. The iOS application connects to the Node.js server to receive all power readings from all the connected smart outlets and can also toggle the power on and off for each outlet.

Greenplace: A User Driven Marketplace For Perishable Goods, Nicolas Higuera

Computer Science and Software Engineering

As the world population grows, food vendors need to be increasingly efficient in the distribution of their products. Products with short shelf-lives need to be distributed as quickly as possible in order to maximize potency. Existing technologies allowing the sale of goods from peer to peer lack key features to optimize usage for perishable goods. GreenPlace provides some of the essential features necessary to distributing perishable goods and managing those orders in an effective manner.

The Struggle Of The Rubiniumite Wars, Timothy Mendez, Evan Peterson, Darren Huang, Kyle Lozier

Computer Science and Software Engineering

The Struggle of the Rubiniumite Warsis a browser-based, one- to two-player, simultaneous turn-based strategy game set amongst the stars. It uses WebGL and Three.js for 3D graphics in the browser, Node.js for game engine and artificial intelligence design on the backend, and Socket.io for networking using websockets. The development group’s inspiration, motivation, and reflections are discussed. Additionally, details on the development of the game engine, database integration with Parse, user registration with Nodemailer, graphics with Three.js and HTML/CSS, and audio with HTML5.

Semi-Automated Test Generation With Spest, Adam Mozek

Computer Science and Software Engineering

Automated black box test generation is a useful tool for developers that allows them to

quickly generate a large number of tests with a wide range of values tested. The current most

popular tool for black box test generation in Java, JML, is lacking in a number of features.

SPEST aims to improve upon existing tools, and provide a black box test generation tool that

can create human readable tests from simple pre and post conditions added as comments to

the Java source code.

X264 Video Encoding Frontend, Alvin Lam

Computer Science and Software Engineering

x264 is a free video codec for encoding video streams into the H.264/MPEG-4 AVC format. It has become the new standard for video encoding, providing higher quality with a higher compression than that of XviD. x264 provides a command line interface as well as an API and is used in popular applications such as HandBrake and FFmpeg. Advanced Audio Coding (AAC) is a very popular audio coding standard for lossy digital audio compression. AAC provides a higher sound quality than MP3 at similar bitrates. This senior project describes the design and implementation of a x264 video encoding frontend that uses …

Universal Uav Payload Interface, Nolan Reker, David Troy Jr, Drew Troxell

Computer Engineering

Unmanned Aerial Vehicle (UAV) technology is becoming increasingly accessible for civilian use. Both open-source and commercial-purpose UAVs can be obtained affordably or even built. However, the platforms available are very segmented in their customization to a specific application (i.e. land surveying, payload delivery). This project aims to create a Universal Payload Interface (UPI) mounted to the underside of multi-rotors or other UAVs to enable the attachment of customizable sensor payloads. These payloads allow a single UAV to be rapidly reconfigured to perform a multitude of tasks.

The Universal Payload Interface facilitates communication between the payload, onboard flight controller, and operator …

Pre-R: Making Healthcare Healthier, Timothy Acorda, Ryan Foletta, Winifred Lee, Thomas Nguyen, Isabella Sarmiento, Brian Truong, Marek Zhang

Computer Engineering

No abstract provided.

Computer Simulations Of Propulsion Of Self-Propelled Flexible Nanobody, Ye Luo

Masters Theses

Swimming bodies such as flagellum and fishes are found everywhere in liquid environment. The research of simulation of swimmers is one of the most important branches among the field of biophysics. This study focus on the direct computer simulation of self-propelled flexible nanobody in fluid field. Two new objectives is studied based on the previous research of Tai-hsien Wu and Dewei ai (2014)[1]. ln Wu's article, the front end of micro swimming body is fixed and the migration of swimmers is neglected. For a further study, one of new targets is to release the head in 3-D simulation fluid area. …

Enterprise Smart Outlet, David Faltmier, Matthew Mcgill, Luke Stencel

Electrical Engineering

The purpose of our senior project, Enterprise Smart Outlet, is to create an electrical outlet which will allow enterprise users to monitor and change their power consumption habits on a large scale. The initial goal of this project is to allow consumers to see their power consumption per outlet in real time, and then using that information conform their future habits to help them conserve electrical energy, and more importantly, money. Three requirements for our project to meet our initial goal are, the outlet will work in a standard electrical outlet and be completely compatible with current electrical standards, the …

Shark Alert: Early Warning System, Cory Peterson, Marc Rauschnot, Taylor Mcclain

Electrical Engineering

The Shark Alert Early Warning System is a device geared toward avid beach goers such as surfers, divers, and swimmers. The system is composed of an ultrasonic transmitter mounted on a shark’s dorsal fin and a receiver worn by the user around the ankle. The receiver alerts the user to the presence of a shark upon ultrasonic signal detection.

The receiver warns the user through both visual and tactile (vibration) alerts to ensure user notification. This circuit was built and tested in the EE labs and Recreation Center pools to determine transmission range. The receiver detects the transmitted signal up …

U-Larm Bike Lock Accessory, Craig Cary

Electrical Engineering

Over the past few years, anti-pollution organizations and activists have encouraged society to use eco-friendly transportation like ride-sharing and biking. According to the San Luis Obispo Police Department, however, bike owners report approximately 269 bike thefts per year. This statistic illustrates the need for a more effective way to protect bicycle property.

The development of an alarm system for the U-Lock bike lock encourages bike owners to ride their bicycles by providing them with additional measures to protect their bicycle property. This U-Lock accessory, when cut, sounds an alarm to alert nearby persons of the theft-in-progress. In order to turn …

Department Of Energy Solar Decathlon 2015, Dante C. Carrillo, Dion A. Celebrado, Jenna I. Denhaan, Christian F. Ferrer, Simon D. Hauser, Audrey L. Rempher, Joseph H. Rohrer, Casey S. Smith

Electrical Engineering

The goal of the Department of Energy (DOE) Solar Decathlon 2015 project is to design, build, and operate a zero-net energy solar-photovoltaic (solar-PV) powered residence. It is an international competition taking place in the fall of 2015 in Irvine, California. The design needs to be attractive, energy-efficient, innovative, and affordable. The Cal Poly team includes students from a variety of majors, including Architecture, Mechanical Engineering, Electrical Engineering, and many more. The different disciplines need to work together to create a functional and cohesive design. For our senior project, we have designed the electrical systems in the home, including the power, …

Test Automation Program For 20-126, Stacia Kwong

Electrical Engineering

No abstract provided.

Smart Shot: Electronic Target With Smartphone Application, Tyler Stuart Pickett, Taylor Jacob Hutchinson

Electrical Engineering

The objective of this project is to develop an electronic system for recreational shooters that functions as a target with real-time feedback. The system provides a user-friendly alternative to paper targets and expensive competition scoring systems. One of the largest challenges presented by this project is balancing cost, durability, and sensitivity. The scope of this project includes the design and implementation of a target assembly, an electronic system, and a smartphone application.

The system is comprised of three main modules: the target, the control module, and the smartphone app. The electronic target communicates wirelessly with the smartphone via Bluetooth. Once …

Rocket Cam: Low Frequency Analog Transmission Of Digital Video, Thomas J. Higdon

Electrical Engineering

The camera module provides data for improving models of dynamic events on Orbital ATK Corp. rockets and aids in troubleshooting, if necessary. Video images provide a valuable addition to the strain, vibration, shock, and acoustic data used for modeling dynamic events, such as stage separations. The cameras can record a duration of video data suitable for capturing a dynamic event and of high enough quality to aid in its modeling. The module readily integrates into the rocket’s current analog data collection systems. The project has further relevance to any other application that necessitates video data transmission over similar limited-bandwidth, analog …

Design Of A High Powered Led Driver, Omar Renteria

Electrical Engineering

Research has shown that LED lighting products have greater energy efficiency, longer lifespans, and lower heat outputs than compared with traditional lighting technologies. An estimated growth of 45 percent per year through 2019 for the LED lighting market should provide a wider variety of LED related products to consumers. The goal of this project; to create a driving circuit that powers a set of high powered LEDs. The implementation of LEDs significantly reduces the power consumption in comparison with other types of light such as incandescent bulbs or CFLs, therefore saving the consumer money.

Current Protection For The Energy Harvesting From Exercise Machines (Ehfem) Project, Colton Crivelli

Electrical Engineering

The Energy Harvesting from Exercise Machines (EHFEM) project intends to create an exercise machine that recycles the energy expended by an athlete operating the machine by sending it to the electric grid. The work done by the user goes through a DC-DC converter and an inverter in order to prepare it for delivery to the grid. A protection circuit ensures that the inverter does not try to pull too much current from the DC-DC converter. The project implements a current protection system that ensures the system doesn’t experience an overcurrent condition.

The Dc House Project: Electrical System Design & Construction, John Bradley

Electrical Engineering

This project entails the design and assembly of the photovoltaic system, switchboard panel enclosure, and battery enclosure for the DC House’s main electrical system. The intended purpose of this project is to provide the electrical framework necessary for future students to easily modify and add to this rendition of the DC House. The principle design implements a variety of renewable energy sources, however this senior project only uses solar power in order to maintain a manageable scope. Each of these renewable energy sources are stepped down to a voltage of 24V and input to a Multi Input Single Output DC …