Digital Commons Network^™

Isopropyl Alcohol Pump For Printed Circuit Boards Using An Arduino, Lawrence Zhu

Computer Engineering

No abstract provided.

Accumulator Volume Sensor Final Project Report, Chris Naughton, Kinwei Yu, Michael George

Mechanical Engineering

Accumulator Volume Sensing Team has developed two sensor designs aimed at detecting the position of the piston within a 4024 accumulator. The two designs include the use of a Renishaw LMA10 magnetic encoder and a SpectraSymbol HotPot linear potentiometer. The magnetic encoder solution drastically increases the accuracy of sensing the piston position compared to the current solutions of both a string-pot and linear variable differential transformer while costing slightly less. The linear potentiometer seeks to provide a solution that drastically decreases the cost compared to the present sensing methods. Both designs call for a modification to one half of the …

Final Design Report: Grasp Data Acquisition Project Axon Vr, Michael Erberich, Jack Schultz, Tyler Yeaman

Mechanical Engineering

No abstract provided.

Electric Smart Load Meter, Johnny Tran

Electrical Engineering

This project details the design of an electric meter that reads the signals of any device plugged into an outlet and displays cost readings that may potentially reduce power consumption. The sensor monitors whether a plugged in device continuously consumes power after completely charging up. For a charging device, the current remains constant until the device reaches 100% charge. Once the device becomes fully charged, the current discontinues for proper power usage. A unique aspect of the meter is that it displays cost per hour, day, and year. Displaying the cost per unit of time creates awareness for customers, potentially …

Active Contact Lens - Low Power Backscattering Sensor-To-Antenna Integration Circuitry, Caleb B. Porter

Electrical Engineering

The Active Contact Lens measures the cornea-scleral radius of the wearer’s eye, which correlates to intraocular pressure (IOP), Glaucoma’s primary indicator. IOP varies throughout the day, and is drastically different from person to person, so constantly measuring it over a period of a few days can provide individualized tracking of the disease’s development and will help doctors develop personalized treatment schedules to treat the disease more precisely.

The Active Contact Lens sensor measures strain, based on the cornea-scleral radius, and reports the results wirelessly, to allow monitoring of an individual’s IOP over time. The lens is powered similarly to a …

Design, Analysis, And Simulation Of A Jitter Reduction Circuit (Jrc) System At 1ghz, Run Bin Yu

Master's Theses

The clock signal is considered as the “heartbeat” of a digital system yet jitter which is a variation on the arrival time of the clock edge, could undermine the overall performance or even cause failures on the system. Deterministic jitter could be reduced during the designing process however random jitter during operation is somehow less-controllable and unavoidable. Being able to remove jitter on the clock would therefore play a vital role in system performance improvement.

This thesis implements a 1GHz fully feedforward jitter reduction circuit (JRC) which can be used as an on-chip IP core at clock tree terminals to …

Scaled Synthetic Aperture Rader Development, Jason Garvey Schray

Master's Theses

Several previous Cal Poly thesis projects involve synthetic aperture radar (SAR), automatic target recognition (ATR), and tracking. SAR data was either accessed from a publicly available database or generated using complex computer modeling software. The motivation for this dual thesis project is to design and construct a scaled SAR system to support Cal Poly radar projects. Ideally this is a low-cost, high resolution SAR architecture that produces raw range Doppler data for any desired target area. To that end, a scaled SAR system was successfully designed, built, and tested. The current SAR system, however, does not perform azimuthal compression and …

Musictrakr, Benjamin Lin

Computer Engineering

MusicTrackr is an IoT device that musicians attach to their instruments. The device has a start and stop button that allows users to record their playing sessions. Each recorded session is sent wirelessly to a cloud database. An accompanying website displays all of the recorded sessions, organized by date. After picking a specific date, the user can view graphs showing total practice time and average session length as well play back any recordings during that date. In addition, the user may add comments to any specific date or recording. Lastly, the user may tag a specific date with a color …

El Capitán: Cal Poly Rose Float Digital Drive System, Gregory Raffi Baghdikian

Computer Engineering

In today’s world of smartphones, self-driving cars, and internet-connected coffee makers, it seems as if computers are contained in everything around us. These “embedded systems” have become critical components of our lives, improving everything about the things they control, from cost, to speed, to simplicity. One area that embedded systems has hardly gained a foothold is in the world of floatbuilding. Most of the floats in the Tournament of Roses Parade, including the one built jointly by Cal Poly San Luis Obispo and Cal Poly Pomona, are technologically very simple, using mostly analog components and rudimentary discrete digital logic to …

Testing Feasibility Of Inductive Power Coupling For Modern Applications, Andrew Burman

BioResource and Agricultural Engineering

This project takes two bifilar tesla coils and uses them to find a % efficiency of power transfer as distances between the coils decrease. The reason this experiment is being conducted is to find possible implications for wireless charging of vehicles using similar style coils. This project conducted experiments on 60 Hz, 400 Hz, and 1 kHz frequencies for a small input signal. The general conclusion is that as the frequency increases more power can be transferred and higher efficiency of power transfer is seen. This project also concluded that it could be possible to get higher efficiency at a …

Manufacturing And Characterization Of Poly (Lactic Acid)/Carbon Black Conductive Composites For Fdm Feedstock: An Exploratory Study, Dylan Fitz-Gerald, Justin Boothe

Materials Engineering

This exploratory study developed methods of manufacturing and characterizing the electrical properties of small batches of conductive composite feedstock for the Fused Deposition Modeling (FDM) manufacturing process, commonly known as 3D printing. We utilized a solution casting process of Poly(lactic acid) (PLA) (Grade 4043D, NatureWorks, LLC.) and Carbon Black (CB) (Vulcan® XC72, Cabot Corp.) in chloroform. The resulting composite precursor was cryogenically treated with liquid nitrogen and milled in a coffee grinder in order to achieve particles that could be fed into the extruder. Composite precursors were dried in a vacuum oven at an elevated temperature of 38°C. Filaments were …

A Stroke Therapy Brace Design, Evan Kirkbride

Electrical Engineering

Victims of stroke often have difficulty with rehabilitation. With limited movement on their affected arm, patients often do not want to move much for physical therapy. In this project, we design a robotic brace that helps stroke patients move their arm more effectively in a reaching or pulling motion. By giving patients more movement in their affected arm than they would have otherwise, patients gain more from rehabilitation. The brace also adapts to the patient’s needs, providing more inclination or resistance as needed for their physical therapy. This kind of therapy engages patients rather than relying on their likely dwindled …

Design And Implementation Of A Three Dimensional Printer Using A Cylindrical Printing Process, Brandon Hoy

Electrical Engineering

Many 3D printers utilize a Cartesian (XYZ) printing process. Implementing a polar coordinate printer providing a faster printing method and introduces new printing algorithms, increasing printing efficiency. This cylindrical 3D printer applies a circular-moving baseplate and a heating printer head (extruder) moving radially and vertically. A processor accepts pre-processed polar data points and transpose the appropriate programmed printing commands to the motors units. The extruder also has a control loop, keeping the temperature inside the desired range. This prototype prints using polylactic acid (PLA) filament. Additionally, a display screen updates every second the: printing time, extruder temperature, and status notifications.

Camera Stabilizer, Nathaniel Bryan, Sean Chappell, Danielle Williams

Electrical Engineering

The goal of this project is to create an affordable camera stabilizer (the “stabilizer”) for consumers to use with cell phones or GoPro cameras. The stabilizer compensates for two axes, pitch and roll, as well as vertical movement. The system (currently only compatible with one cell phone model) is handheld and uses a combination of brushless DC motors, an Inertial Measurement Unit (IMU), and a microcontroller to compensate for the operator’s movements, stabilizing the phone for nonshaky, high quality video recording. The stabilizer provides a lowcost alternative to professional stabilization solutions employed in the production of featurelength films; the system …

Cal Poly Supermileage Electronic Fuel Injection, Alexander Pink

Electrical Engineering

Cal Poly Supermileage is a student-run engineering club that builds prototype gasoline vehicles optimized maximum fuel-efficiency. To power their vehicles, the Supermileage team makes use of single-cylinder, 4-stroke, electronically fuel-injected (EFI) gasoline engines. This report details the development, iterative design & test cycles, and integration of an EFI system for the Supermileage club. This project develops an EFI system that interfaces to the most common types of sensors found in the low-power Supermileage-range of engines, including throttle-position sensors, manifold absolute pressure sensors, gear-tooth hall-effect sensors, variable-reluctance position sensors, engine coolant temperature sensors, intake air temperature sensors, and exhaust oxygen sensors. …

Car Safe, David Van Workum

Electrical Engineering

The Car Safe project helps protect parents and caretakers from the dangers associated with leaving children in hot vehicles. The device supports parents through notifying them of the child’s wellbeing and status while within an automobile. Specifically, the device monitors the child’s ergonomic experience and the spatial proximity between the caretaker and child. Car Safe utilizes this information and determines if the child finds himself in a dangerous environment. Due to its compact design, the device functions independently of a specific car seat design, allowing customers to integrate Car Safe in the car seat environment of their choosing.

Rapid Battery Exchange (Rbx), Daniel Rostom

Electrical Engineering

Electric vehicles have begun to hit the main stream market, with sales raising form under 20,000 in 2001 to over 110,000 per year since 2014 [1]. With new models hitting the market every year, and more people becoming conscious about their fossil fuel usage, this trend will only continue until there are more electric vehicles than combustion vehicles on the road. A major drawback of electric vehicles is their limited range, and relatively long recharge times. Even with advancements in battery charging speed, such as the Tesla super charger, able to provide up to 90 miles of range in just …

Exertion Control, Travis Taylor

Electrical Engineering

Current wearable fitness devices give the user after-the-fact fitness data, but little real-time feedback. Exertion Control, a new wearable device, continuously measures the user’s heart rate, creates a heart rate target, and helps the user reach it. This project completes the senior design and master’s thesis requirements and contains two milestones. The senior design product continuously measures the wearer’s heart rate and logs it with a user-friendly interface. This data models the heart’s exertion response and recovery response. The master’s thesis device refines the closed control loop with the user to give them a workout optimized to fit their needs.

Active Charge Balancing For Cardiac Stimulation, Maci Miri

Electrical Engineering

Worldwide, there are about 3 million people who have pacemakers, with 10,000 new implantations of ICD’s each month. [heart.org] Due to the gravity and importance of the function that ICD’s provide, these devices must be extremely reliable and highly effective. However, because of the high tolerances of IC manufacturing, stimulation circuits for pacemakers may be slightly unmatched and over time, may have a net DC charge applied to the tissues in the heart. Extra charge pumped into body tissues is dangerous for the patient’s health; the pH of the tissue can be raised and corrosion of the stimulating electrodes may …

Robotic Overbed Table, Jonathan Lantz

Electrical Engineering

Traditionally overbed tables have simple and cheap designs, yet contain many disadvantages compared to the design proposed in this report. Disabled or bedridden persons, often require the use of a bedside table either in hospital environments or at home. Unfortunately, many modern overbed tables require the user to get out of bed and move in order to adjust and position the table. Incorporating a singlebutton control panel that allows the user to make adjustments and access other features independently, creates more accessible product. Integrated subsystems must control all motors and interfaces with an easy access control panel in order to …

Complex Filters As As A Cascade Of Of Buffered Gingell Structures: Design From From Band-Stop Constraints, Samuel Robert Johnston

Master's Theses

This thesis presents an active Complex Filter implementation that that creates a transfer function with with a single real pole and a complex zero. The two-input/two-output network developed in in this thesis responds differently based upon upon the relative phase difference of of the two inputs. If a negative ninety-degree phase difference occurs between the two inputs, the filter will exhibits a bandstop response. While a positive ninety-degree phase difference exhibits a bandpass response. This topology is relatesd to to Gingell’s RC-CR polyphase topology but because of of the use of of op-amps, can be cascadedd without without suffering loading …

Design Of Inexpensive And Easy To Use Diy Internet Of Things Platform, Samuel R. Jaffe

Master's Theses

This thesis focuses on the design and implementation of a new, inexpensive, and less complex system for a Do-It-Yourself (DIY) Internet of Things (IoT) platform. The hardware aspects focus on a new chip called the ESP8266 which contains both microcontroller and WiFi connectivity capabilities in an extremely affordable package. The system uses the Arduino IDE to program the ESP8266, which is known to be an extremely user-friendly environment. All other software is both free and easy to use. Past methods of creating IoT projects involved either expensive hardware, often ranging from $50-$100 per node, or complicated programming requiring a full …

Low-Frequency Series Loaded Resonant Inverter Characterization, Alfredo Medina

Master's Theses

Modern power systems require multiple conversions between DC and AC to deliver power from renewable energy sources. Recent growth in DC loads result in increased system costs and reduced efficiency, due to redundant conversions. Advances in DC microgrid systems demonstrate superior performance by reducing conversion stages. The literature reveals practical DC microgrid systems composed of wind and solar power to replace existing fossil fuel technologies for residential consumers. Although higher efficiencies are achieved, some household appliances require AC power; thus, the need for highly efficient DC to AC converters is imperative in establishing DC microgrid systems. Resonant inverter topologies exhibit …

Hall Effect Modeling In Fem Simulators And Comparison To Experimental Results In Silicon And Printed Sensors, Leonardo A. Frem

Master's Theses

Finite element method simulation models for thin-film semiconductor-based Hall sensors were developed using secondary data in order to understand their behavior under strong magnetic fields. Given a device geometry and charge carrier density and mobility, the models accurately calculated sensor resistance, Hall voltage under a normally-incident constant magnetic field, and expected offset from a population of Hall devices. The model was successfully matched against data from integrated chip Hall sensors from St. Jude Medical. Additionally, the feasibility of creating Hall effect devices with common carbon ink was explored experimentally. The material properties obtained from testing these ink-based devices through the …

Design Of An Integrated Acceleration Acquisition Subsystem To Satisfy High-Speed And Low-Area Requirements For Cubesats, Ryan J. Rumsey

Master's Theses

Cal Poly San Luis Obispo’s PolySat team is designing the Multipurpose Orbital Spring Ejection System (MOSES) in order to record acceleration data during the launch of CubeSats as well as to provide GPS coordinates to locate the position of CubeSats once they are injected into orbit. This work focuses on the design and development of the acceleration data acquisition (DAQ) subsystem of MOSES. This subsystem is designed around the need for a high-speed sampling system of at least 200 kHz across four channels of data, plus low-area limitations in the MOSES form factor which is roughly half the size of …

Usb-Powered Turntable "Turn T", Gerardo Sevilla, James Lougaris

Electrical Engineering

No abstract provided.

Ism S-Band Cubesat Radio Designed For The Polysat System Board, Craig Lee Francis

Master's Theses

Cal Poly’s PolySat CubeSat satellites have begun to conduct more complex and scientifically significant experiments. The large data products generated by these missions demonstrate the necessity for higher data rate communication than currently provided by the PolySat UHF radio. This thesis leverages the proliferation of consumer wireless monolithic transceivers to develop a 250kbps to 2000kbps, 2W CubeSat radio operating within the 2.45GHz Industrial, Scientific, and Medical (ISM) radio band.

Estimating a link budget for a realistic CubeSat leads to the conclusion that this system will require a large deployable CubeSat antenna, large earth station satellite dish, and a fine-pointing attitude …

Out-Of-Loop Compensation Method For Op-Amps Driving Heavy Capacitive Loads, Shubham Gandhi

Master's Theses

It is well known that real op-amps do not share most of the desirable characteristics of an ideal one, particularly those of gain and output impedance. When presented with a capacitive load, such as a MOSFET or ADC, feedback in an op-amp circuit can quickly become unstable. This thesis studies and characterizes an op-amp’s output impedance and how its interaction with this type of load creates a parasitic pole which leads to instability. Applying ideas from feedback control theory, a model for studying the problem is developed from which a generalized method for compensating the undesirable circumstance is formulated.

Even …

Oceanographic Instrument Simulator, Amy Chen

Master's Theses

The Monterey Bay Aquarium Research Institute (MBARI) established the Free Ocean Carbon Enrichment (FOCE) experiment to study the long-term effects of decreased ocean pH levels by developing in-situ platforms [1]. Deep FOCE (dpFOCE) was the first platform, which was deployed in 950 meters of water in Monterey Bay. After the conclusion of dpFOCE, MBARI developed an open source shallow water FOCE (swFOCE) platform located at around 250 meter of water to facilitate worldwide shallow water experiments on FOCE [1][2]. A shallow water platform can be more ubiquitous than a deep-water platform as shallow water instruments are less expensive (as it …

Wide-Band Gap Devices For Dc Breaker Applications, Olukayode O. Sodipe

Master's Theses

With the increasing interest in wide-band gap devices, their potential benefits in power applications have been studied and explored with numerous studies conducted for both SiC and GaN devices. This thesis investigates the use of wide-band gap devices as the switching element in a semiconductor DC breaker. It involves the design of an efficient semiconductor DC breaker, its simulation in SPICE, construction of a hardware prototype and the comparative study of SiC and Si versions of the aforementioned breaker. The results obtained from the experiments conducted in the process of concluding this thesis show that the SiC version of the …