Electro-Mechanical Systems Commons^™

Magnetic Bearing For Bently Nevada Rk4 Rotor Kits, Sean Fowler, Garrett Olson

Mechanical Engineering

Active Magnetic Bearings (AMB) are contact free bearings that support loads by magnetic levitation. This is accomplished by generating magnetic forces with electric current through a series of electromagnets surrounding a suspended rotor mass. Along with a set of electromagnets, an AMB assembly also consists of power amplifiers for each electromagnet, a controller, and proximity sensors. The proximity sensors provide rotor position feedback to the control system, which modulates power to the amplifiers [4]. Magnetic bearings are used in several industrial applications today, including but not limited to compressors, turbines, pumps, motors, and generators. Advantages of their utility include very …

Analytical Solution For Speed To Achieve A Desired Operating Point For A Given Fan Or Pump, Michael F. Kocher, Jeyamkondan Subbiah

Department of Agricultural and Biological Systems Engineering: Faculty Publications

The Affinity Laws for fans (and pumps) provide a way of determining new fan or pump speed given fan or pump performance curve data and a desired operating point (combination of flow rate and pressure) that does not fall on the curve. However, the affinity law calculations require using a point on the curve (hereafter referred to as the “basic point”) to determine the new speed. Most references regarding the Affinity Laws do not give a clear description of the method for determining the “basic point”, and improper selection of this point can affect the results considerably. This article describes …

High Temperature Hepa Filter Test Unit Upgrades, Alexander Krippner, Ian Corcorran, Michael Burlando

Mechanical Engineering

No abstract provided.

A Concept Validation Of A Magnetometry-Based Technology For Detecting Concealed Weapons In Vehicle Door Panels, Nar Vang

Master's Theses

Acts of insurgency have become an increasing threat resulting in extensive measures being taken by the law enforcement authorities to mitigate their devastating effects on human life and infrastructure. This thesis introduces a magnetometry-based information, and signal processing methodology for detecting concealed ferrous objects in vehicle body panels. From extensive literature research, it was observed that while magnetic sensors have been used in a variety of related applications, but they have not been extensively applied to the on-road detection of firearms and explosives concealed in vehicles. This study utilized an extensive experimental protocol for preliminary concept validation. The main idea …

Tadpole Tandem Electrically Assisted Tricycle, Austin Frederickson, Anthony Jacques, Kris Lawrence, Preston Mcelroy

Mechanical Engineering

The purpose of this senior project was to investigate the possibility of making bikes (as a regular mode of transportation) look much more appealing to the general public. To that end, an electric motor assist system was added to make it easier for the operators of the vehicle. A fairing was added to protect the rider from wind and rain, and an electrical subsystem consisting of a microcontroller and many other components was also added. The electrical subsystem was meant to store the information of different riders, calculate calories burned using a heart beat sensor, and increase visibility using strategically-placed …

Vibration Table For Environmental Chamber, Michael Czabaranek, Dylan De Caussin

Mechanical Engineering

No abstract provided.

Evaluation Of Design Tools For The Micro-Ram Air Turbine, Victor Fidel Villa

Master's Theses

The development and evaluation of the design of a Micro-Ram Air Turbine (µRAT), a device being developed to provide power for an autonomous boundary layer measurement system, has been undertaken. The design tools consist of a rotor model and a generator model. The primary focus was on developing and evaluating the generator model for the prediction of generator brake power and output electrical power with and without rectification as a function of shaft speed and electrical load, with only basic manufacturer specifications given as inputs. A series of motored generator evaluation test were conducted at speeds ranging from 9,000 to …

Team Nathan Suspension, Frankie J. Wiggins, Alex D. Seitz, Justin P. Bautista

Mechanical Engineering

Nathan Cooper is an 8-year old boy with Spinal Muscular Atrophy (SMA). SMA has affected Nathan’s muscle development and requires him to use the Standing Dani™ mobility device. The Standing Dani is a motorized standing wheelchair, or Wheelstand. Nathan controls and uses it to get around. Though the Standing Dani performs well for most functions, it has some distinct issues. The primary issue that this project addresses is its lack of suspension and the discomfort that Nathan feels as a result. After talking with our client, we developed several specifications generally related to geometry, safety, vehicle dynamics, and reliability. Many …

Mobile Solar Pv Trainer, Matthew Myers, Matthew Clause, Lawrence Smith

Mechanical Engineering

The aim of the Mobile Solar PV Trainer Project was to design, construct and test a versatile and robust laboratory training rig for the Cal Poly Electrical Engineering department. This project was inspired by the desire of one or more California Polytechnic State University electrical engineering professors to add laboratory components to two established upper division electrical engineering courses in photovoltaic panels and solar power. This report contains a detailed description of the trainer’s desired specifications, our ideation process, a thorough description of the selected trainer design including part drawings, assembly documentation and a bill of materials as well as …

Friction Test Machine, Kyle Raymon Schless, Lynda Beatriz Tesillo, Mustapha Nadri

Mechanical Engineering

No abstract provided.

Bellevue-Santa Fe Charter School Solar Panel Project, Dulce Arroyo Martinez, Henrik Lee, Moises Quiroz, Timothy Iafrate

Mechanical Engineering

This project covers the design, manufacture, and installation of solar panel frames on a charter school in Avila Beach, CA. Through preliminary research regarding important factors (such as solar movement, ideal panel angle, and site-specific factors), a frame that meets the standards set forth in the California Building Codes was designed. After approval by presiding authorities, parts specified in the design were ordered, inspected upon arrival, and manufactured to the design as necessary. Much of the challenge was related to the installation aspect of the project—coordination with the proper authorities and correct submission of applications was integral to the success …

Fabrication Of Magnetic Two-Dimensional And Three-Dimensional Microstructures For Microfluidics And Microrobotics Applications, Hui Li

Theses and Dissertations--Mechanical and Aerospace Engineering

Micro-electro-mechanical systems (MEMS) technology has had an increasing impact on industry and our society. A wide range of MEMS devices are used in every aspects of our life, from microaccelerators and microgyroscopes to microscale drug-delivery systems. The increasing complexity of microsystems demands diverse microfabrication methods and actuation strategies to realize. Currently, it is challenging for existing microfabrication methods—particularly 3D microfabrication methods—to integrate multiple materials into the same component. This is a particular challenge for some applications, such as microrobotics and microfluidics, where integration of magnetically-responsive materials would be beneficial, because it enables contact-free actuation. In addition, most existing microfabrication methods …

Long Life Electrochemical Diodes For Continuous Electrowetting, Mehdi Khodayari, Ben Hahne, Nathan B. Crane

Faculty Publications

The rate of electrochemical reactions in some systems varies with the polarity of the overpotential on the working electrode, introducing diode-like behavior at the electrode/electrolyte interface. However, with repeated bipolar cycling, the electrochemical current damages the electrodes. We have connected electrochemical diodes in series with opposing polarities to reduce the diode current while charging a capacitive circuit. We have previously used this capacitive circuit arrangement to actuate aqueous droplets continuously using the electrowetting (EW) effect. In this study, the performance of electrochemical diodes under repeated voltage cycles is investigated. Aluminum and titanium electrodes in contact with three electrolyte solutions (0.1 …

Barbeque Grill Temperature Distribution Design Improvement, Peter Gobell, Connor Mcgill, Thomas Willson

Mechanical Engineering

Team License to Grill set out to asses Bull Outdoor Products, Inc.’s barbeques and quantify the apparent uneven temperature distribution or “hot spots” and “cold spots” across the grill. This testing was accomplished with the design and fabrication of a test fixture allowing for accurate and repeatable temperature collection across the barbeque. With results that matched the sponsor’s claims of hot and cold spots, an engineering model was made using heat transfer and thermodynamic equations. Once the model somewhat resembled the experimental data, it was used to suggest different modifications that would allow for better temperature distribution. It was discovered …

High Temperature Filter Test Unit Upgrades, Blair Frandeen, Will Schill, Erick Shewmaker, Joshua Turgeon

Mechanical Engineering

The purpose of this project was to improve the existing High Temperature Filter Test Unit (HTTU) by optimizing performance and adding new features. These features include viewing ports and a camera system for observation of tests, a leak detection system, and a flame impingement system. Additional considerations included improving the current operation of the HTTU by reducing test time and energy loss. The HTTU is designed to test High Efficiency Particulate Air (HEPA) filters at temperatures up to 1300 ˚F, creating conditions which simulate a fire in a chemical processing facility. The HTTU was originally built as a Cal Poly …

Bicycle Wheel Test Machine, Dylan Harper, Kevin Hom, Ross Williams

Mechanical Engineering

In recent years, the cycling industry has witnessed huge advancements in bicycle components and materials. The age old goals of speed and low weight are still present today, but the pursuit of these goals may be reducing the structural stability of various components integral to wheel performance, including the wheel hub bearings. These bearings are invaluable to bicycles but little is known about how the forces and loads applied to a bicycle affect the performance of these bearings. Broken axles and hubs are indicators of significant stresses within the hub, but little is known about how the resulting deformation affects …

Autonomous Collision Avoidance, Thomas Stevens, Elliot Carlson, Ian Painter

Mechanical Engineering

A steering controlled, autonomous collision avoidance system has been developed by California Polytechnic State University. This system represents a step in the direction of fully autonomous driving, while allowing the driver to maintain control of the vehicle during normal driving conditions. In the case of an imminent collision, the system removes control of the vehicle from the user and autonomously steers around the obstacles. The final system is able to avoid two static obstacles with a 95% pass rate and one moving obstacle with a 50% pass rate. With full scale, fleet wide, implementation of this system it is expected …

Cal Poly Brocade Challenge 2013, Chandler Morehardt, Alexa Coburn, Juan Silva, Kerry Sun, Greg Wang, Raul Chagoya, Jd Torres

Architectural Engineering

No abstract provided.

Rebounder Fatigue Test Machine, Caroline Reeves, Will Robertson, Ethan Flory

Mechanical Engineering

JumpSport, a company that designs and sells trampolines and trampoline accessories, has sponsored this senior project team to design, build, and test a trampoline fatigue test machine. The machine must simulate a person jumping on the trampoline to test the life of JumpSport’s fitness trampolines and kids’ trampolines. Partway through the design process, the objectives were altered and this senior project team was tasked with merging with another Cal Poly senior project group to create an all-inclusive test machine to accommodate both full-trampoline testing and individual bungee cord testing.

The final design is centered on a slider crank linkage driven …

Floating Electrode Electrowetting On Hydrophobic Dielectric With An Sio2 Layer, Mehdi Khodayari, Benjamin Hahne, Nathan B. Crane, Alex A. Volinsky

Faculty Publications

Floating electrode electrowetting is caused by dc voltage applied to a liquid droplet on the Cytop surface, without electrical connection to the substrate. The effect is caused by the charge separation in the floating electrode. A highly-resistive thermally-grown SiO2 layer underneath the Cytop enables the droplet to hold charges without leakage, which is the key contribution. Electrowetting with an SiO2 layer shows a memory effect, where the wetting angle stays the same after the auxiliary electrode is removed from the droplet in both conventional and floating electrode electrowetting. Floating electrode electrowetting provides an alternative configuration for developing advanced electrowetting-based devices.

High Performance Low Temperature Solid Oxide Fuel Cells With Novel Electrode Architecture, Yu Chen, Qian Liu, Zhibin Yang, Fanglin Chen, Minfang Han

Faculty Publications

In this study, we have fabricated high performance low temperature solid oxide fuel cells (LT-SOFCs) with both acicular anodes and cathodes with thin Gd-doped ceria (GDC) electrolyte film. The acicular Ni-Gd_0.1Ce_0.9O_2−δ (Ni-GDC) anode was prepared using freeze drying tape casting, while the hierarchically porous cathode with nano-size Sm_0.5Sr_0.5CoO₃ (SSC) particles covering an acicular GDC skeleton was prepared by a combination of freeze drying tape casting and self-rising approaches. The acicular electrodes with 5–200 μm pores/channels enhance mass transport, while SSC particles of about 50 nm in the cathode promote …

Formula Sae Turbocharger Engine Development, Eric Griess, Kevin Mccutcheon, Matthew Roberts, William Chan

Mechanical Engineering

This project, Formula SAE Turbocharger System Development, was sponsored by the Cal Poly, San Luis Obispo Formula SAE team. The team proposed this project in order to have a powerful yet lightweight engine so they can be extremely competitive at their competition. The baseline output of the single cylinder 450cc engine (2006 Yamaha WR450F) was 46 horsepower and 27 ft-lb of torque. The goal of this project was to increase the output of that engine to 60 horsepower and 35 ft-lb through the use of a turbocharger.

Robotic Fingerspelling Hand For Deaf-Blind Communication, Brian Fang, Colby Dixon, Trevor Wong

Mechanical Engineering

Robotic fingerspelling hand for the deaf-blind. The hand forms the shapes of the American Manual Alphabet with 11 servos. The project was sponsored by The Smith-Kettlewell Eye Reaserch Institute.

Formula Hybrid Drivetrain Design, Zachary (Zak) Mcfarland, Alex Pruitt, William Domhart

Mechanical Engineering

The Formula Hybrid senior project group was tasked with designing and building a drivetrain system for the Cal Poly Society of Automotive Engineers (SAE) Formula Hybrid (FHSAE) team. FHSAE gave customer requirements for performance and geometry for the drivetrain and the FHSAE rulebook has guidelines regarding safety requirements. The team chose to compete in the electric category of the 2012 FHSAE competition. After getting feedback from previous car performance and researching different powertrain options, the senior project team arrived at three conceptual ideas. Using a quality function deployment method, the senior project team chose the concept where two motors independently …

Fluidic Assembly At The Microscale: Progress And Prospects, Nathan B. Crane, Onursal Onen, Jose Carballo, Qi Ni, Rasim Guldiken

Faculty Publications

Assembly permits the integration of different materials and manufacturing processes to increase system functionality. It is an essential step in the fabrication of useful systems across size scales from buildings to molecules. However, at the microscale, traditional “grasp and release” assembly methods and chemically inspired self-assembly processes are less effective due to many scaling effects. Many methods have been developed for improving microscale assembly. Often these methods include fluidic forces or the use a fluidic medium in order to enhance their performance. This paper reviews basic assembly theory and modeling methods. Three basic assembly strategies (tool-directed, process-directed, and part-directed) are …

A Material System For Reliable Low Voltage Anodic Electrowetting, Mehdi Khodayari, Jose Carballo, Nathan B. Crane

Faculty Publications

Electrowetting on dielectric is demonstrated with a thin spin-coated fluoropolymer over an aluminum electrode. Previous efforts to use thin spin-coated dielectric layers for electrowetting have shown limited success due to defects in the layers. However, when used with a citric acid electrolyte and anodic voltages, repeatable droplet actuation is achieved for 5000 cycles with an actuation of just 10 V. This offers the potential for low voltage electrowetting systems that can be manufactured with a simple low-cost process.

A Digital Hydraulic Valve, Actuated Using A Piezoelectric Linear Motor, Brian C. Bevill

Purdue Polytechnic Directed Projects

Proportional control in hydraulics is widely utilized. The most widely used current types of proportional valves utilize solenoid technology. While this technology has been around for decades and has been proven an effective means of control, there is always a demand for improved performance of advancing technologies. Integrating piezoelectric devices as a means to control hydraulic systems helps advance control for hydraulic systems.

Piezoelectric stack devices have been used to control hydraulic systems with success. Advantages of these stacks include being relatively small with a high power to weight ratio, using less energy than solenoid operations, and being fast acting. …

Mobility Aid: A Dual Purpose Walker And Scooter, Zack Blois, Robia Choi, Kristin Dills

Mechanical Engineering

The Mobility Aid project was proposed by Theresa Mortilla and Idee Shapiro. The goal of the project was to design and build a device that can quickly and easily transform between a mobility walker and an electric scooter to allow for more freedom of mobility. The inspiration for this project arose from the fact that Theresa suffers from multiple sclerosis in her legs and can only walk for about thirty minutes at a time until she gets too fatigued and must sit down and rest. This device would provide her with the ability to continue moving while giving her legs …

Implementation Of A Conrad Probe On A Boundary Layer Measurement System, Charles Rocky Ulk

Master's Theses

This thesis presents the design, calibration, and performance evaluation of a type of two-hole pressure probe anemometer known as a Conrad probe, as well as its subsequent implementation on an autonomous, compact boundary layer measurement device and its first application for subsonic in-flight measurements of a swept wing boundary layer. Calibration of the Conrad probe was accomplished using two calibration functions and a non-nulling method for resolving in-plane flow velocity direction and magnitude over a range of ±30 degrees. This approach to calibration and application offered the advantages of rapid data acquisition with lower energy consumption than alternative methods for …

Evaluation Of Quasi-Static Indentation Damage In Aluminum Honeycomb Core - Graphite/Epoxy Sandwich Structures, David Eisenberg

Renée Crown University Honors Thesis Projects - All

Sandwich composites utilize a low density core and relatively stiff face sheets. These structures are ideal for applications that require high compressive strength, high bending stiffness, and very low weight such as aerospace vehicles. However, one problem with sandwich composites is their susceptibility to low velocity impact damage. Low velocity impacts result in both external damage, in the form of dents, and internal damage, in the form of core crushing, face sheet delaminations (two adjacent plies separating from one another), fiber fractures and matrix cracks. In general, it is assumed that visibly evident damage will be repaired. Barely visible impact …