Electrical and Computer Engineering Commons^™

Hardware-In-The-Loop Reaction Wheel Testbed With Camera Vision, Abigail Romero, Harvey Perkins, Stephen Kwok-Choon

College of Engineering Summer Undergraduate Research Program

Reaction wheels are widely used in aerospace systems as a method of attitude control. This research was focused on the design, development, and testing of a hardware-in-the-loop reaction wheel testbed that can be used for research and teaching applications related to satellite navigation and control. This project successfully utilized commercial off-the-shelf components to develop a reaction wheel capable of controlling the orientation of a freely rotating platform, as well as tracking objects using computer vision.

Dripline: A Distributed Experiment Control System, Eric Gonzalez, Ben Laroque, Noah Oblath

STAR Program Research Presentations

Project 8 is a nuclear physics experiment which seeks to measure the mass of neutrinos. The experiment requires the use of various pieces of hardware which need to be controlled, and from this need, a software system named Dripline is being developed. Because most researchers have some knowledge in Python and it is easier to understand the syntax of Python as opposed to C++, a Python application programming interface (API) is being created to allow any researcher working with Dripline ease of use. As development progresses, features may be added or removed as needed which requires constant testing, debugging, and …

Relationship Between Time-Constants And 3db Cutoff Of High-Order Damped Lti Systems, Vladimir I. Prodanov, Katherina Prodanov

Electrical Engineering

This paper deals with linear time-invariant (LTI) systems and examines the link between the 3dB cutoff and time-constants. It shows that the cutoff frequency of a low-pass damped network can be estimated from the reciprocal of a p-norm calculated from the system's time-constants. Furthermore, to achieve good accuracy the p factor must have a fractional value, for example, p=1.7. Two formulas are derived, and their performance evaluated using Monte Carlo simulations which reveal a sub-3% error for most cases.

Experimental Study And Modeling Of The GM-I Dependence Of Long-Channel Mosfets, Michael Cheng, Vladimir I. Prodanov

Electrical Engineering

This paper describes an experimental study and modeling of the current-transconductance dependence of the ALD1106 and ALD1107 arrays. The study tests the hypothesis that the I-g _m dependence of these 7.8 μm MOSFETs conforms to the Advanced Compact Model (ACM). Results from performed measurements, however, do not support this expectation. Despite the relatively large length, both ALD1106 and ALD1107 show sufficiently pronounced `short-channel' effects to render the ACM inadequate. As a byproduct of this effort, we confirmed the modified ACM equation. With an m factor of approximately 0.6, it captures the I-g _m dependence quite well. The paper also introduces …

Alumni Grassroots Leadership Enables Sponsored Course Development, Vladimir I. Prodanov, John Greene

Electrical Engineering

This paper presents a lab-centric course development where alumni, employed by an IAB member company, play a pivotal role. Recently the lead author of this paper qualified for a sabbatical leave and the college enthusiastically approved the proposal (a 400-level elective in networked sensors). He considered two class structures: lecture-only and lecture-lab. While lecture-lab is the desired mode of instruction, the development of such a course would take at least 2 quarters. Since extended sabbaticals are only partly funded by the university the creation of a lecture-lab course hinged on the availability of a sponsor. Simultaneously an alumnus, now with …

Method For Selecting Coupling And By-Pass Capacitors In Multi-Stage Linear Circuits, Vladimir I. Prodanov, Dale Dolan

Electrical Engineering

A method for selecting a set of coupling and by-pass capacitors is presented. The approach uses short-circuit time-constant analysis and for a given −3 dB cut-off frequency minimises the total capacitance used. This study offers a derivation of design formulas and shows their use via examples.

Uhf Rfid Antenna Impedance Matching Techniques, Kamron Sockolov, Dean Arakaki

Electrical Engineering

The modified T-match network uses planar inductive strips for conjugate matching Radio Frequency Identification (RFID) Integrated Circuits (RFICs). Narrow and broadband matching techniques and electromagnetic simulations are applied in [1] for specific designs. This paper extends these efforts through antenna element parameterization and design trade-off analysis. Narrow and broadband designs are fabricated; antenna input impedance and tag range tests confirm predictions.

Lecture Videos To Supplement Electromagnetic Classes At Cal Poly San Luis Obispo, Dean Y. Arakaki

Electrical Engineering

Electromagnetics and Transmission Lines is a fundamental, yet difficult subject in the Electrical Engineering (EE) field. To help improve information retention, a series of lecture videos was created to supplement traditional lectures, to facilitate in-class discussions, and to improve students’ proficiency and interest in electromagnetics.

Engineering electromagnetics classes at California Polytechnic State University, San Luis Obispo cover fundamentals to understand and analyze cell phone communications, radar systems (air traffic control, law enforcement), and biomedical imaging (MRI). However, this subject also requires considerable mathematics preparation in vector calculus, differential equations, linear algebra, and background in both physics and EE.

Lecture videos …

Instructables.Com As A Tool To Improve Student Outcomes And Promote Community Engagement (Work-In-Progress), Andrew Danowitz

Electrical Engineering

Project-based Learning (PBL) has become a popular pedagogical tool in Engineering. Projects force students to put theory learned in lecture into practice, exposes students to some of the nonidealities of real systems (imperfect instruments, uncooperative systems, etc.) that are difficult to convey in lecture or homework, and ideally motivates students by showing how course material is related real-world engineering problems. This work discusses my preliminary and ongoing research into using Instructables.com—a user-content generated website of “Do It Yourself” tutorials—as a tool to help amplify the benefits students derive from PBL. Specifically, I require students to document their projects in an …

A Paramedic Method Drill Master To Improve Student Writing, David Braun

Electrical Engineering

Engineering instructors have students write reports in order to help learn difficult concepts, data analysis, challenging problem solving, communication skills, and critical thinking. Sadly, many students seem to prefer obfuscating the subject matter and key ideas by using painfully unclear writing. An instructor dismayed by poor prose in submitted assignments has numerous familiar options available. Consider just a few:

1. Ignore the poor writing

2. Mark every error directly

3. Mark every error with a marginal comment

4. Give general feedback about the poor writing over the entire assignment

5. Expect students to rewrite and resubmit work

6. Change careers …

A Prototype Microwave Cavity Control Circuit For Use In Next Generation Free Electron Laser, Josh Thompson, Peter Neal Barrina, Jiayi Jiang, Joe Frisch, Steve Smith, Daniel Van Winkle

STAR Program Research Presentations

One of the current programs at SLAC National Accelerator Laboratory is the Linac Coherent Light Source, or LCLS. Using the existing hardware of the last third of their linear accelerator (or “linac”), SLAC has created one of the most energetic X-ray free electron lasers (or “FEL”). Since 2009, LCLS has used this FEL to perform a wide range of experiments across all sciences, most notably ultrafast filming at the molecular scale. As requests for beam-time with this laser increases, SLAC is purposing a linac upgrade to better match this demand. This upgrade, named LCLS-II, will replace existing copper radio frequency …

Foss Big Data Storage Solution, Nurdeen Salami

STAR Program Research Presentations

NASA projects require a reliable approach to store large volumes of data. Accordingly, it is crucial to adopt a lightweight, reliable, and scalable database. Current NASA databases bear costly license fees with undesirable speed and flexibility. The purpose of utilizing the AERO Institute as an IT test bed, or “Sandbox,” is to design, build, test, and implement software solutions prior to transfer to NASA projects. Cassandra coupled with the Astyanax API is a viable solution for storing big data. Store a minimum of 2GB of C-FOSS data in multiple file formats (.csv, .log, .xml, and .jpg). Use benchmark tests to …

Space Race: Capturing An Orbiting Sample And A Nation’S Imagination, Stephanie La Liberte, Andrew Chavarin, Shubham Gogna, C. Daniel Thomas, Vy Phung, Gabriel Udomkesmalee

STAR Program Research Presentations

A proposed architecture for future planetary sample return missions would consist of capturing on-orbit a sample container (collected from the surface of a planetary body and launched into space) and transferring the sample container into an earth return/reentry capsule. A challenge to this proposed architecture is integrating space applicable sensor technologies with sufficient capturing devices. While useful technologies on Earth, Earth-related rendezvous/capture technologies, such as magnetic field sensors, sound-based sensors, and Earth orbit-based radios like GPS, are not applicable to space. Inspired by the in-orbit sample capture challenge, NASA JPL has designed the Space Rendezvous And Capture Experiment (Space RACE). …

Organic-Based Microwave Frequency Absorbers Using Corn Stover, Ben Smythe, Sean Casserly, Dean Arakaki

Electrical Engineering

Commercial antenna test chambers (anechoic) currently use polyurethane foam absorbers on chamber interiors to eliminate undesired radio-frequency (RF) reflections. While effectively absorbing microwave signals, polyurethane material particulates over time adding contaminants to clean rooms and reducing absorber lifetime. These absorbers also release toxic gas when operating under high temperatures and pose a health risk to direct-contact personnel. This paper presents reflectivity analysis and performance of alternative organic-based (corn stover) microwave frequency absorbers for use in anechoic chambers. These absorbers are composed of renewable materials and eliminate the toxic gas release problem for polyurethane materials under high power test conditions. Preliminary …

Multi-Technique Broadband Microstrip Patch Antenna Design, Daniel Colles, Dean Arakaki

Electrical Engineering

Microstrip patch antennas offer low profile and small footprint advantages, but limited operating bandwidth. Substantial research focuses on broadband techniques. This paper presents the design, simulation, fabrication, and characterization of a 30% bandwidth microstrip patch antenna that incorporates multiple broadband techniques while minimizing footprint area. Methods include patch shape, dielectric thickness, and coupling slot optimization, with capacitively-coupled L-probe feeds. The final design incorporates an electrically thick dielectric and circular-E patch geometry. Microstrip L-probe feed and coupling slot dimensions were optimized via HFSS simulations. The final design was fabricated, and then tested in an anechoic chamber. The new design has measured …

A Class-C Amplifier Linearized By A Constant Conduction Angle Biasing Circuit, Gursewak Singh Rai, Vladimir I. Prodanov, Stephen Garber

Electrical Engineering

This work presents a dynamic biasing topology capable of linearizing a Class-C power amplifier (PA). The topology utilizes a control loop that senses the operating conditions of the power device by means of a scaled replica. The loop operates on the principle of keeping the conduction angle constant and thereby ensuring linearity. The work details some of the design considerations that should prove useful to a designer wanting to implement the topology in an RF integrated circuit. Measurement results from a fully-functional low-frequency prototype bring merit to the topology.

Tools And Methods To Optimize The Analysis Of Telescopic Performance Metrics On Sofia, Steven R. Wilson, Holger Jakob, Stefan Teufel, Zaheer Ali, Jeffrey Van Cleve, Brian Eney, Greg Perryman

STAR Program Research Presentations

SOFIA is an infrared observatory mounted on a modified 747 engineered to do infrared astronomy at 45000 feet. The telescope equipment contains a number of sensors and stabilizers that allow the telescope to capture images while mounted in a moving plane. We have developed methods to analyze the performance of the telescope assembly that will help improve the stabilization and image capturing performance of the observatory. Here we present reusable methods to analyze telescope performance data that will enable improvements in the quality of the scientific data that is produced by the SOFIA. This poster focuses on the multi-flight performance …

Feedback Stabilization At Spear3, Daniel Kelley, Jeff Corbett

STAR Program Research Presentations

The SPEAR3 synchrotron lightsource at SLAC relies on a sophisticated radio frequency (RF) timing system to maintain current – electrons – in the storage ring. One problem SPEAR3 operators have dealt with is the thermal expansion of one of the cables supporting this RF timing system. As the cable expands and contracts with the diurnal rise and fall of the sun, the phase of the RF in the cable shifts. This shifting phase affects the timing accuracy of electron injections into the storage ring.

A common feedback control algorithm PID (Proportional Integral Derivative) has countless applications in engineering. PID feedback …

Identifying At-Risk Students: How Use Of Optional Study Materials And Collection Of Graded Work Correlate With Academic Performance, Vladimir I. Prodanov

Electrical Engineering

We report on a study designed to identify students at risk by monitoring certain academic behaviors. Two different approaches were implemented. The first one involves monitoring student access of optional homework problems. While this approach was successful in the early identification of students at-risk, optional homework (as opposed to mandatory one) degrades attainment of learning objectives. The second approach relies upon “counting” of uncollected work. Since no grades were posted, the only way for the students to keep track of their performance was to collect their work. Failure to collect graded work, we argue, is indicative of weak motivation, poor …

Methanol Fuel Safety - A Practical Guide, Art Maccarley

Electrical Engineering

This guide was written initially for the students at Cal Poly engaged in the conversion of IC engines to methanol fuel, especially my students working on methanol projects in my course “Automotive Technologies for a Sustainable Future”. It may be of interest to anyone considering the conversion or operation of an engine on methanol, or to those that handle methanol for other purposes. One of many Materials Safety Data Sheets (MSDS) for methanol that can be found online is: http://www.midi-inc.com/pdf/MSDS_Methanol.pdf.

Empirical Model For The Transconductance-Current Dependence Of Short-Channel Mosfets, Vladimir I. Prodanov

Electrical Engineering

This work is concerned with the g_m-I dependence of sub-micrometer MOSFETs. The transconductance-current expression given by the Advanced Compact Model (ACM) is reviewed and simple modification is proposed. The modification yields an expression which (with proper parametrization) captures the g_m-I dependence of short-channel MOSFETs. The proposed expression is “universal” in the sense that it is capable of modeling the g_m-I dependence of long-channel MOSFETs, short-channel MOSFETs, and resistively-degenerated BJTs.

Technology Portal For Energy Efficient Buildings, Larry D. Hermanson, Daniel Studer, Annie Mroz

STAR Program Research Presentations

Project: Technology Portal for Energy Efficient Buildings

Date: August 2, 2012

Author: Larry Hermanson

Mentor: Daniel Studer

Cohort: Annie Mroz

Lab site: National Renewable Energy Laboratory (NREL)

Buildings account for 71% of the electricity demand and 39% of the primary energy consumption in the United States. The Commercial Buildings Group at NREL provides builders, designers and building owners accurate information to significantly improve the energy efficiency of new and existing buildings. The Technology Portal for Energy Efficient Buildings will increase the accessibility of standardized and credible energy performance data for all building systems, thereby allowing building owners to better evaluate …

Commissioning Of The Asta Laser Lab With Uv Pulse Length Characterization, Daniel Kelley, Jeff Corbett

STAR Program Research Presentations

The Linac Coherent Light Source (LCLS) at SLAC depends on a photocathode electron gun to provide the linear accelerator with the raw material – electrons – used for making X-ray laser pulses. The photocathode used in the LCLS Injector is a clean copper plate in high vacuum. When the cathode is struck with high energy UV light, electrons are liberated from its surface and then accelerated down the linac with radio-frequency electric fields. These fast-moving bunches of electrons are directed through an undulator magnet to radiate X-ray light.

Although scientists have been using photocathode techniques at SLAC for 25 years, …

Structural Damage Detection Using Artificial Neural Networks And Wavelet Transform, Arthur Shi, Xiao-Hua Yu

Electrical Engineering

With the ever-increasing demand for the safety and functionality of civil infrastructures, structure health monitoring (SHM) has now become more and more important.

Recent developments in computational intelligence and digital signal processing offer great potentials to develop a more efficient, reliable, and robust structure damage identification system. In this paper, the application of artificial neural networks and wavelet analysis is investigated to develop an intelligent and adaptive structural damage detection system. The proposed approach is tested on an IASC (International Association for Structural Control)-ASCE (American Society of Civil Engineers) SHM benchmark problem. Satisfactory computer simulation results are obtained.

Traffic Signal Optimization Using Ant Colony Algorithm, David Renfrew, Xiao-Hua Yu

Electrical Engineering

Traffic signal control is an effective way to improve the efficiency of traffic networks and reduce users’ delays. Ant Colony Optimization (ACO) is a meta-heuristic algorithm based on the behavior of ant colonies searching for food. ACO has successfully been employed to solve many complicated combinatorial optimization problems and its stochastic and decentralized nature fits well with traffic networks. This research investigates the application of the ant colony algorithm to minimize user delay at traffic intersections. Various ACO algorithms are discussed and a rolling horizon approach is also employed to achieve real-time adaptive control. Computer simulation results show that this …

In-Class Lecture Recording: What Lecture Capture Has To Offer To The Instructor, Vladimir I. Prodanov

Electrical Engineering

The purpose of this study is to determine the impact of lecture recording upon the instructional faculty. The following aspects are explored: 1) impact on class enrollment; 2) impact on class attendance; 3) usefulness of obtained statistical results for course improvement. The study is based upon data collected in a junior-level Electrical Engineering class with enrollment of 76 students. The data was collected using anonymous surveys and Blackboard’s statistical tracking utility. The results from the survey show that providing lecture recordings does not have significant impact upon students’ decision to attend lectures, but it has pronounced impact upon their enrollment …

Student Perception Of Lecture Video Use As A Means To Increase Time For In Class Problem Solving Applications, Dale Dolan, Vladimir I. Prodanov, Taufik

Electrical Engineering

The purpose of this study is to examine student perceptions of lecture video use as a means to increase available time for in class problem solving in a teaching and learning context. A portion of face to face lectures was replaced with prerecorded lecture video whose viewing was assigned for homework. The freed lecture period was used for additional in class problem solving development, without sacrificing the theory and background that is fundamental. In order to assess the effectiveness of the change in format, student perception was assessed through an anonymous online survey. The survey was given at the completion …

Design And Assembly Of An Antenna Demonstration System, Alexander J. Hempy, Michael P. Civerolo, Dean Y. Arakaki

Electrical Engineering

This paper describes the design, assembly, and operation of a self-contained wireless demonstration system that required only dc power supplies. The system demonstrated polarization effects, radiation patterns, gain, directivity, and signal interference from environmental barriers from dipole, corner reflector (simulated antenna array), Quagi, and embedded patch antennas. The system included an RF oscillator, high-frequency amplifiers,RF bandpass filters, a signal-strength indicator, and multiple adjustable antenna-mounting platforms.

Wavelength Dependence Of Transverse Mode Coupling With/Without E-Block Of Gan Laser Cavity, K. Lal, G. Chavoor, Xiaomin Jin

Electrical Engineering

Transverse mode wavelength dependence in the gallium nitride (GaN) laser cavity is a new topic. Modal analysis simulations are run to optimize the blue GaN-based laser diode with a wavelength of 400, 430, and 460 nm. It is shown that the optical confinement factor (OCF) has a strong dependence on wavelength of emission and electron-block (e-block) thickness. The OCF can be changed from 4.9% at a 460-nm wavelength to 7.6% at 400 nm, which is a 55% difference. The effect of adding an e-block layer of different widths is also investigated with results showing that an e-block layer can change …

Electric Vehicle Safety, Art Maccarley

Electrical Engineering

No abstract provided.