Engineering Commons^™

Capacitive Pcb Security For Active Tamper And Alteration Detection, Casey Petersen

Electrical and Computer Engineering ETDs

The purpose of the research presented is to establish the viability of using capacitive based sensors for the purpose of hardware security at the Printed Circuit Board (PCB) level. Capacitive sensors are traditionally used to sense changes to the areas surrounding the sensing pads in applications such as sensing proximity, position, humidity, fluid levels and much more.

The specific sensor used for this research is an inductor-capacitor (LC) based Capacitance-to-Digital Converter. This configuration is virtually immune to EM noise because it is a tank circuit and therefore filters out the noise which, in the past, caused reliability issues with these …

Practical Vortex Beam Generation, Nedime Pelin Mohamed Hassan Salem

Dissertations

Vector vortex beams are monochromatic electromagnetic wave fields carrying spin angular momentum (SAM) and orbital angular momentum (OAM). Spin angular momentum is associated with the polarization of the field, whereas OAM yields an azimuthal field dependence of the form exp( jqφ), where φ is the azimuthal angle, and q is an integer designating the helicity order, which is also known as the topological charge of the vortex beam. Vortex beams owe their names to the characteristic on-axis phase singularity and amplitude null.

In this study, a new method to generate vector vortex beams in the microwave regime is devised …

Properties Of Matter, Mike Jackson, Holly Haney

High School Lesson Plans

Students will investigate the relationship(s) between thermal and electrical properties of matter. First, students will use a multimeter and temperature probe to investigate the relationship between electrical resistance and temperature of an electrical resistor composed of metals. They will then graph collected data to analyze the relationship and draw a conclusion as to their relationship. They will then perform the same investigation on a thermal resistor made of a semiconducting substance and analyze that collected data. Finally, using ClaimEvidence-Reasoning (CER) structure, students will use their experimental evidence to state the similarities and differences between the electro-thermal properties of metals and …

Wireless Sensors For Health Monitoring Of Marine Structures And Machinery, Francisco David Rojas Calvente

PhDs

Remote structural and machinery health monitoring (SMHM) of marine structures such as ships, oil and gas rigs, freight container terminals, and marine energy platforms can ensure their reliability. However, the wired sensors currently used in these applications are difficult and expensive to install and maintain. Wireless Sensor Networks (WSN) can potentially replace them but there are significant capability gaps that currently prevent their long-term deployment in the harsh marine environment and the structurally-complex, compartmentalised, all-metal scenarios with high volume occupancy of piping, ducting and operational machinery represented by marine structures. These gaps are in sensing, processing and communication hardware and …

Flip-Chip (Fc) And Fine-Pitch-Ball-Grid-Array (Fpbga) Underfills For Application In Aerospace Electronics—Brief Review, Ephraim Suhir, Reza Ghaffarian

Mechanical and Materials Engineering Faculty Publications and Presentations

In this review, some major aspects of the current underfill technologies for flip-chip (FC) and fine-pitch-ball-grid-array (FPBGA), including chip-size packaging (CSP), are addressed, with an emphasis on applications, such as aerospace electronics, for which high reliability level is imperative. The following aspects of the FC and FPGGA technologies are considered: attributes of the FC and FPBGA structures and technologies; underfill-induced stresses; the roles of the glass transition temperature (T_g) of the underfill materials; some major attributes of the lead-free solder systems with underfill; reliability-related issues; thermal fatigue of the underfilled solder joints; warpage-related issues; attributes of accelerated life …

Search Methods For Mobile Manipulator Performance Measurement, Samuel Nana Yaw Amoako-Frimpong

Master's Theses (2009 -)

Mobile manipulators are a potential solution to the increasing need for additional flexibility and mobility in industrial robotics applications. However, they tend to lack the accuracy and precision achieved by fixed manipulators, especially in scenarios where both the manipulator and the autonomous vehicle move simultaneously. This thesis analyzes the problem of dynamically evaluating the positioning error of mobile manipulators. In particular, it investigates the use of Bayesian methods to predict the position of the end-effector in the presence of uncertainty propagated from the mobile platform. Simulations and real-world experiments are carried out to test the proposed method against a deterministic …

Investigation Of The Skin Effect In Alternating Currents, Matthew Liang

The International Student Science Fair 2018

My research is on the investigation of the skin effect in alternating currents. The skin effect is when an alternating current tends to flow on the surface of the conductor, such that the current density is highest near the surface, and decreases with greater depths in the conductor. This is due to the alternating current inducing changing magnetic fields, which in turn induces currents that oppose the original flow of current, resisting the current flowing through the centre the most. This reduces the effective cross-sectional area of the conductor and increases the resistance, causing increased power losses. This effect becomes …

Energy Conversion System For Travelers (Ecost), Thipok Bovornratanaraks

The International Student Science Fair 2018

We have innovated “The Energy Conversion System for Travelers” or the ECoST. With the fact that most travelers have wheeled cabin-bags, whilst walking, the wheels will rotate so why don’t we harvest electricity from this kinetic energy? We thus install our innovation, the ECoST, to the bag to generate electricity from the spinning wheels. The electricity is then kept in the storage unit and ready to charge your empty battery devices in an emergency case via a USB port. To make life easy, our ECoST was designed to replicate the power bank charging method; therefore, we can charge …

Solar-Powered Bushfire Detection Mechanism, Aryaman Sud

The International Student Science Fair 2018

This project designed a prototype preventative measure for heat-induced disasters like bushfires and general home fires. The motivation for this project was the loss of life and property due to wildfire in rural Australia. The micro-controller will send an alert message and sound an alarm when the temperature value exceeds or equals the set temperature of . It is programmed using the programming language embedded ‘C’. Comprising of a solar panel, siren, temperature sensor and a Bluetooth module, this eco-friendly device can provide digitalised warnings to homes and farms where protection matters most.

Simplistic programming using the KEIL IDE software …

Solar-Powered Bushfire Detection Mechanism, Aryaman Sud

The International Student Science Fair 2018

This project designed a prototype preventative measure for heat-induced disasters like bushfires and general home fires. The motivation for this project was the loss of life and property due to wildfire in rural Australia. The micro-controller will send an alert message and sound an alarm when the temperature value exceeds or equals the set temperature of . It is programmed using the programming language embedded ‘C’. Comprising of a solar panel, siren, temperature sensor and a Bluetooth module, this eco-friendly device can provide digitalised warnings to homes and farms where protection matters most.

Simplistic programming using the KEIL IDE software …

Low Voltage Ride Through Enhancement For Wind Turbines Equipped With Dfig Under Symmetrical Grid Faults, Francis Mwasilu

Tanzania Journal of Engineering and Technology (TJET)

In modern power systems with significant penetration of wind-turbines (WTs), improvement of low voltage ride through (LVRT) capability of WTs equipped with doubly-fed induction generators (DFIGs) is an important issue. Thus, this paper proposes a low voltage ride through (LVRT) strategy, which comprise of a capacitor connected in series with an inductor both connected in parallel to a resistor. The configuration is then connected to a small series resistor via a pair of antiparallel-Thyristors. The circuit and its switching control scheme of the proposed LVRT circuit are designed to: minimize the transition times, maintain the RSC connection to the rotor-windings, …

Investigation Of The Skin Effect In Alternating Currents, Matthew Liang

The International Student Science Fair 2018

My research is on the investigation of the skin effect in alternating currents. My project is broken down into 4 sub-aims. The first aim would be, to be able to mathematically model the distribution of current in the radius of the wire, which consists of the applications of the Maxwell equation and solving zeroth order differential Bessel equations of the first kind. The next aim would be to computationally plot out the desired current readings as the depth of the wire increases from the surface, using the Matlab software. The third aim that I have would be conducting an experiment, …

Energy Conversion System For Travelers (Ecost), Thipok Bovornratanaraks

The International Student Science Fair 2018

We have innovated “The Energy Conversion System for Travelers” or the ECoST. With the fact that most travelers have wheeled cabin-bags, whilst walking, the wheels will rotate so why don’t we harvest electricity from this kinetic energy? We thus install our innovation, the ECoST, to the bag to generate electricity from the spinning wheels. The electricity is then kept in the storage unit and ready to charge your empty battery devices in an emergency case via a USB port. To make life easy, our ECoST was designed to replicate the power bank charging method; therefore, we can charge …

Brushless Direct Current Motor Control For Inspired Flight, Aidan James Mccoy

Computer Science and Software Engineering

Brushless direct current motors have become a very common part of many modern electronics. Although they are more expensive and less robust than conventional brushed direct current motors, they provide large advantages in control, power output, longevity as well as efficiency. To make these motors run, they need more than just power. Each motor needs a separate motor controller that is responsible for taking in a signal for what speed/torque to run the motor at, and then managing the current flow to the motor to keep it spinning while fitting within these boundaries. Brushless direct current motors have a set …

Fpga-Based Dsp System, Aaron Nguyen

Computer Engineering

The purpose of this project is to create a modular FPGA-based filtering system for audio in VHDL. The final implementation has a working input, output, and filtering system but the filtering system still must be fine-tuned.

Analog Sorting Using Pulse Width Modulation, Riley C. Olson

Computer Engineering

As time goes on, computers become more and more powerful. However, as processing time becomes less of a limiting factor for computing tasks, power consumption takes its place for many tasks. This paper proposes and tests a new method for sorting analog signals. This new sorting method converts analog signals into Pulse Width Modulated(PWM) signals of varying duty cycle , which are then sorted by a simple network of combinational logic, and then converted to a normal binary representation. In order to implement this new method, multiple circuits had to be designed and and tested to ensure their functionality and …

"Dual Peaks" Analog Distortion Guitar Effects Pedal, Dave Raul Breuer

Computer Engineering

The Dual Peaks distortion pedal is an analog effects pedal for electric guitar that distorts and boosts the guitar signal in order to achieve tonal characteristics often heard in music genres such as blues, rock, hard rock, and metal. Dual Peaks aims to remedy the current distortion pedal design, and provide a new spin not often provided in the majority of pedals. Dual Peaks contains two separate distortion channels which provide the player with a vast array of distortion and overdrive tones at the press of a switch. Also, Dual Peaks has a "noise gate" and 3-band equalizer circuits built …

Collision Avoidance Smartphone, Matt Columbres, Aaron Parisi, Joey Schnecker, Luis Wong

Electrical Engineering

There are many instances in day-to-day life where people cannot or would rather not pay full attention to their surroundings. Walking while preoccupied with a smartphone or walking while blind are excellent examples where technology could be used to make the task of avoiding 2collisions reactive, instead of proactive. A device which monitors a user’s surroundings and notifies the user when a potential collision is detected (and, additionally, notifying them as to where the obstacle is with respect to them) could be used to make walking distracted less of a hazard for the user and those around the user and …

Versatile Usb Powered Turntable, Kyle P. Mccarry

Electrical Engineering

People enjoy vinyl music’s warm sound, user participation, and nostalgic feel, but the large physical size and seemingly immobile system requirements prevent vinyl turntables branching into digital music dominated realms. USB ports power many important everyday devices. A USB powered turntable increases record player adaptability, versatility, and portability thus expanding usable turntable scenarios. The manual turntable plays seven to twelve-inch vinyl at 33 1/3 or 45 rpm. It includes a stylus, magnetic phono cartridge, tonearm, 45-rpm adapter, motor, audio output, and several setting switches and knob for easy use.

Digital Guitar Effects Pedal, Ian Charles Lang

Electrical Engineering

The Digital Guitar Effects Pedal assists guitarists in creating music by implementing several useful functions. The pedal takes an analog input signal from an electric guitar, performs digital operations on it, and outputs a modified analog signal to an external guitar amplifier. Pedal functions include: an easy-to-use instrument tuner, a looper which records and plays back music segments, a tap tempo mode allowing easy synchronization with other instruments, and various guitar effects (distortion, echo, and vibrato, among other examples). The pedal user interface displays the current selected function, and allows easy switching between effects.

Roborodentia Robot: Treadbot, Stephen C. Schmidt

Computer Science and Software Engineering

This document is a summary of my contest entry to the 2018 Cal Poly Roborodentia competition. It is meant to be a process overview and design outline of the mechanical, electrical, and software components of my robot.

The Design, Building, And Testing Of A Constant On Discreet Jammer For The Ieee 802.15.4/Zigbee Wireless Communication Protocol, Alexandre J. Marette

Master's Theses

As wireless protocols become easier to implement, more products come with wireless connectivity. This latest push for wireless connectivity has left a gap in the development of the security and the reliability of some protocols. These wireless protocols can be used in the growing field of IoT where wireless sensors are used to share information throughout a network. IoT is being implemented in homes, agriculture, manufactory, and in the medical field. Disrupting a wireless device from proper communication could potentially result in production loss, security issues, and bodily harm. The 802.15.4/ZigBee protocol is used in low power, low data rate, …

A Multiphase Modified Boost Converter With Reduced Input Current Ripple: Combined Capacitors, Omri Nissan

Master's Theses

The delivery of high power and smaller footprints through a non-isolated topology demands for the use of multiphase topology in DC-DC converters. Multiphase reduces the ripple observed on both the input and output waveforms; however, it may not be enough to connect to sensitive power sources such as renewable energy sources. A single-phase modified boost converter demonstrates the ability to acquire very minimal input current ripple by addition of passive components. The expansion to multiphase topology is the next logical step for higher power application while furthering the low input current ripple benefit. In this thesis, the multiphase modified boost …

Arm Mke1xf Mcu Replatform, Nathan Hong, Derek Lung, Japsimran Singh, Bevin Tang

Computer Engineering

After Cal Poly Racing’s electrical team began to hit the technical limits of the ADC and other I/O features of the current 8-bit Atmel AT90 microcontroller unit, it became clear that an upgrade was due. This replatforming project takes the functionalities of the old, 8-bit architecture, and aims to provide a 32-bit version using the ARM MKE1xF MCU. With the idea of having a working PCB as a stretch goal, the scope of the library development was limited to enable base functionality. Thus, the only libraries developed were for the Timer, ADC, SPI, UART, and CAN. Additionally, this document discusses …

Smart Espresso Machine, Hasham Ali, Justin L'Heureux, Hayden Yeung, Pei Hang Zhang

Electrical Engineering

With the recent “Internet of Things” trend, more and more home devices are connected to the Internet. Smart light bulbs, smart thermostats, smart door locks; just to name a few. These smart appliances enable users to view their status and control their settings remotely with just a few clicks on the smartphone. Moreover, the arrival of intelligent personal voice assistants such as Amazon Alexa revolutionized how users interact with these smart appliances. Nowadays, users are able to control these devices by just speaking.

If controlling smart devices is so easy, why not have your morning cup of joe be that …

Iridium Adc, Bill Blakely

Electrical Engineering

Today's modern digital audio systems are pushing performance boundaries. Most high quality audio digital to analog converters are capable of 24 bit, 96 kHz conversion. Professional audio interfaces frequently use 24 or 32 bit 192 kHz sample rates. These systems are able to achieve dynamic ranges greater than 100 dB, and distortion on the magnitude of single parts per million. This project proposes a high resolution analog digital converter (ADC) to measure and characterize these types of devices.

The proposed system will be capable of 24 bit conversion and an extended frequency range compared to the typical 20 Hz to …

Electric Upgrades - Supercapacitor Electric Bicycle, John Chen, Wilson Fletcher, Spencer Esparza

Electrical Engineering

Supercapacitors provide high current capabilities compared to conventional lithium-ion batteries, allowing for fast charging and discharging of electrical energy. This project seeks to test the benefits of supercapacitors in an electric bicycle unit in order to gain higher regenerative energy. The main components of the bicycle are its regenerative motor, supercapacitor array, and motor controller. Developing the project will provide data on the feasibility of using alternative battery storage and charging.

Induction Coil Power Generator, Steven Chi Li

Electrical Engineering

Over the years, society has evolved technologically to the point where we become dependent on technology. Today, nearly everybody have smartphone devices. This leads to the popularity of portable chargers since portable devices do not have a constant source of power. Even most portable chargers share the same problem as portable devices, which they both share a finite amount of battery power before needing to recharge at a power outlet. Ultimately, they are just temporary solutions to the problem of the lack of power. However, society assumes the abundance of electric power sources where they view them as an infinite …

High-Bandwidth Iop Sensing Backscatter Transceiver, Mark Manuel

Electrical Engineering

This document describes the design and build of a mobile phone attachment that communicates with an ASIC embedded smart contact lens. The portable device enables patients and clinicians to conveniently and instantaneously measure intraocular pressure (IOP). The device replaces bulky and expensive benchtop RF synthesizer and signal analyzer machines required for communication to the smart contact lens into a portable and convenient device. The transceiver transmits VHF ISM band radio and can capture reflected backscatter On-Off-Keying modulated message signals at bandwidths from DC to 130MHz.

Mgsnn2: A New Eco-Friendly Wide Band Gap Semiconductor, Krystal R. York

Masters Theses

Materials having a wide band gap (above 2 eV) can provide new alternatives for existing light-emitting diodes (LEDs) and other opto-electronic devices. Currently, many such devices are comprised of low-earth-abundant elements, such as gallium and indium, which are harmful to the environment to extract and difficult to recycle. Alternatively, MgSnN2 is an unexplored material comprised of earth abundant elements which benefit from a mature recycling infrastructure. This material has a predicted band gap of 3.43 eV, indicating that it could be a viable substitute for GaN (band gap of 3.4 eV), which is commonly used in LEDs and other device …