Mechanical Engineering Commons^™

A Differential Planetary Gear Model With Backlash And Teeth Damage, Xi Wu, Jim Meagher, Andrew Sommer

Mechanical Engineering

Planetary gear trains can be more compact and efficient as power transmissions than fixed axis gear trains but are also more complicated and less understood in terms of vibration health monitoring. A practical differential planetary gear train, which combines two inputs and one output, is studied using multi-body dynamics software. Backlash between the sun gear and planet gears are precisely specified to avoid teeth interference and undercut. In order to calculate accurate impact forces, an impact model is chosen. Tooth geometry errors are created on the sun gear. Constraints and contact forces to the model are applied as close as …

An Advanced Numerical Model Of Gear Tooth Loading From Backlash And Profile Errors, Andrew Sommer, Jim Meagher, Xi Wu

Mechanical Engineering

This study demonstrates the early transient dynamic loading on teeth within a fixed-axis gear transmission arising from backlash and geometric manufacturing errors by utilizing a non-linear multi-body dynamics software model. Selection of the non-linear contact parameters such as the stiffness, force exponent, damping, and friction coefficients are presented for a practical transmission. Backlash between gear teeth which is essential to provide better lubrication on tooth surfaces and to eliminate interference is included as a defect and a necessary part of transmission design. Torsional vibration is shown to cause teeth separation and double-sided impacts in unloaded and lightly loaded gearing drives. …

Low-Cost Prosthetic Leg For The Vida Nueva Prosthesis Clinic, Sarah M. Baker, Justin G. Lekos, Jen Van Donk, Kevin Yamauchi

Mechanical Engineering

The Piernas de Vida team partnered with the Vida Nueva Clinic of Prostheses and Orthoses in Choluteca, Honduras to design, plan, and implement a prosthetic foot that could be manufactured entirely by the technicians at the clinic in order to reduce their costs and ultimately allow them to serve more patients each year. Currently, the clinic uses a prefabricated prosthetic lower limb provided by the International Committee of the Red Cross (ICRC) which can be adapted to both transDfemoral and transDtibial patients. The team has successfully developed a foot, currently called the Layer Foot, which can be used by the …

An Advanced Controller For A Semi-Active Wheelchair Suspension, David J. Smith

Master's Theses

An Advanced Controller for a Semi-Active Wheelchair Suspension was designed, built and tested.  The suspension consisted of a Goodyear 1S3-011 air spring, IQ Valves high speed proportional solenoid valve, and a custom made accumulator.  Several controller designs specific to semi-active suspensions were designed and tested.  The controllers investigated were skyhook, acceleration driven damping, and a combined control law employing both a dual and single sensor version.  The implementation of skyhook control suffered performance degradation from the idealization due to particular elements of hardware, however acceleration driven damping showed a marked and statistically significant improvement over skyhook control, in hardware, by …

Cal Poly Rose Float Electric Vehicle, Jennifer Slone, Jason Sherrett, Dionysios Pettas, Timothy Baldwin

Mechanical Engineering

(1) Background:

The Cal Poly Rose Float is currently powered by a pair of V-8 internal combustion engines. This is the second project in a three phase effort to replace the existing drive engine with an electric motor powered by a DC bus. The main goal of this phase of the project is to get the motor selected in phase one spinning.

(2) Results:

Originally, the project involved programming a microcontroller to achieve motor control. The decision was made, early on, to approach this task in a different manner due to the team’s minimal background in programming and mechatronics. The …

Asme Human Powered Vehicle, Benjamin Knaus, Philip Basmadjian, Nick Supat

Mechanical Engineering

Speed Solutions has been contracted to design and build a Human Powered Vehicle (HPV) frame and drivetrain for the Cal Poly HPV club to use in their 2011 race season. This project is being funded by the Cal Poly HPV club and their sponsors. The goal is to design, test and build a bicycle frame that the HPV club can attach to a fairing of their design. Primary design considerations will include speed, weight, cost, rider ergonomics, reliability and ease of repair. This vehicle will be used to compete in ASME’s Human Powered Vehicle Challenge (HPVC) series of races.

Adapted Recumbent Bike, Kurtis Mundell, Dane Tiemeier, Laura Yakuma, Darius Yu

Mechanical Engineering

The adapted recumbent project was to redesign a disabled veteran’s recumbent bicycle.  The main areas of concern were the crank pedal, chain tension, braking and steering system, and ergonomics. Since the customer is an avid biker, this bike will be used often, so the design is based on the ease of repair and replacement.  The crank system was redesigned to a lightweight, adjustable part with chain clearance and high strength. The chain tension was improved by replacing the existing single idler wheel/chain tube system with a dual idler wheel system. The dual idler has a titanium sprocket in one of …

An Investigation Of Initially Delaminated Composite Sandwich With Delamination Arrest Mechanism Under Buckling Loading, Tony D. Tran

Master's Theses

This thesis involves the development of a fiberglass-foam composite sandwich structure with the introduction of delamination arrestment keys; therefore, a study of an initially delaminated composite sandwich structure was the experimental analysis on multiple configurations in how the arrestment keys are placed.

The first part of this thesis research was to the experimental design and manufacturing of the composite sandwich plates. These plates were later cut down to the specific test dimensions and manufacturing processes for the composite sandwich plates and test specimens were created. The composite sandwich plates were manufactured using a vacuum resin infusion process. The dimensions of …

Robot Crawling Device And Tee Table, Todd P. Trauman, Kyle M. Colvin, David Charles Fantz

Mechanical Engineering

As golf becomes a more frequently enjoyed activity, equipment manufacturers such as Hot Stix Golf require updated testing mechanisms to actively compete in their respective markets. One such testing device is a golfing robot nicknamed the “Iron Byron”. Two issues were asked to be addressed for the senior project. First, the robot was practically immobile unless taken apart and moved with a forklift. The request from Hot Stix was to mobilize the robot so that it could easily be transported with minimal use of external help. Secondly, the initial tee-table was both poorly-designed and missing altogether. The new tee-table needed …

Water Well Drilling Rig Final Project Report, Alexander (Alex) Wargnier, Thad Jablonski, Coel Schumacher

Mechanical Engineering

In this report, the improvements of a previously produced cable tool drilling rig are described. The purpose of the rig is to drill water wells for use in Africa in order to provide safe drinking water to many in need. An affordable, effective, and controllable rig is the design goal for this project. With the San Luis Obispo Rotary Club sponsoring the project the design team of WHole Engineering have made necessary design choices to manufacture the product. Actions performed include background research of existing drilling technologies, analysis of top concepts for the controlling mechanism, and selection for the final …

The Quadricycle Hand And Foot Cycle, Marissa Chin, Parker Drennan, Spencer Nelson, Kevin Reidy

Mechanical Engineering

This report documents the design process from concept generation to manufacturing for a hand and foot powered cycle named the Quadricycle.  The Quadricycle project is a joint effort at California Polytechnic State University in San Luis Obispo between the Mechanical Engineering and Kinesiology Departments.  The project objectives are to design a portable cycle that can be powered by hands and feet simultaneously in order to provide recreation and rehabilitation for a person with a disability.  This project is funded under a grant by the National Science Foundation (NSF).

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 …

Foam Wars Ii, Sumant Advani, Sivadas Menon, Casey Pieplow

Mechanical Engineering

The team producing Foam Wars II consists of three Mechanical Engineering students and five Kinesiology students (three the first two quarters and two the last quarter) at California Polytechnic State University, San Luis Obispo. The project is the second iteration of Foam Wars as a senior project at Cal Poly, sponsored by Dr. Kevin Taylor under the National Science Foundation grant. Persons with disabilities often feel limited when it comes to recreational activities and Foam Wars would provide them with an outlet to interact and engage themselves in a group setting. The game consists of various wheelchair attachments that would …

Universal Play Frame Vi, Justin Bazant, Cullen Crackel, Anthony Franceschi

Mechanical Engineering

This design report details the design process utilized by Adaptive Exercise Designs (AED) in creating the sixth design of the Universal Play Frame (UPF). The UPF is an adaptive frame which supports a variety of devices that allows athletes in wheelchairs with limited range of motion to participate in physical activity. The past five frame designs do not meet the needs of the Friday Club due to complications with function and time constraints. To ensure all of Fridays Club's needs were met, the problem was better defined by converting the customer requirements into engineering specifications. The design process our team …

Piedras Blancas Clock Works, Andrew James, Andrew Jupin, Matt Weber

Mechanical Engineering

In 1875, the Piedras Blancas Lighthouse was built to warn ships sailing the California coast of the hazards of the rocky shore. In 1949 a fierce storm damaged the top portion of the lighthouse and the eight ton cast iron and brass assembly had to be replaced by a much lighter piece that still served the purpose of warning oncoming vessels. The former top portion came to rest in downtown Cambria and is still there today, enclosed in a glass room to be observed by visitors and townspeople. Today, the Piedras Blancas Light station is cared for by the Bureau …

Artificial Skin Tactile Sensor For Prosthetic And Robotic Applications, Ross James Miller

Master's Theses

To solve the problem of limited tactile sensing in humanoid robotics as well as provide for future planned mechanical prostheses, an innovative tactile sensor system was created and embedded into two realistic-looking artificial skin gloves. These artificial skin tactile sensors used small piezoelectric ceramic disks to measure applied force at multiple points on each glove. The gloves were created using silicone rubber to simulate both the texture and look of human skin, while maintaining both flexibility and durability. The sensor outputs were buffered by high-impedance voltage-following operational amplifiers, and then read sequentially using a multiplexing scheme by a microcontroller. Sensor …

Modeling And Numerical Investigation Of Hot Gas Defrost On A Finned Tube Evaporator Using Computational Fluid Dynamics, Oai The Ha

Master's Theses

Defrosting in the refrigeration industry is used to remove the frost layer accumulated on the evaporators after a period of running time. It is one way to improve the energy efficiency of refrigeration systems. There are many studies about the defrosting process but none of them use computational fluid dynamics (CFD) simulation. The purpose of this thesis is (1) to develop a defrost model using the commercial CFD solver FLUENT to simulate numerically the melting of frost coupled with the heat and mass transfer taking place during defrosting, and (2) to investigate the thermal response of the evaporator and the …

A Study Of Golf Club Head Kinematics Near Impact, Stephen James Murphy, David Wadsworth Lavelle, Kevin Philip Melancon

Mechanical Engineering

No abstract provided.

Work In Progress - Role Of Faculty In Promoting Lifelong Learning: Initial Findings, John Chen, Susan M. Lord, Katharyn Nottis, Michael Prince, Candice Stefanou, Jonathon Stolk

Mechanical Engineering

Calls for educational reform emphasize the need for student-centered learning approaches that foster lifelong learning. To be a lifelong learner includes characteristics consistent with those of self-directed learners, such as being curious, motivated, reflective, analytical, persistent, flexible, and independent. Instructor support of students’ self-directed learning (SDL) development relies on understanding and balancing these factors in the classroom. Engineering educators play a critical role in influencing outcomes related to SDL through their design of courses that support students’ transitions from controlled to autonomous learning behaviors. This study will examine a variety of engineering courses and pedagogical approaches. Each will be characterized …

Motorcycle Data Acquisition System, Jonathan Luke Harmse

Biomedical Engineering

No abstract provided.

State Space Model Of A Light Weight Flexible Telescope, Chi-Yeh Hsu

Master's Theses

The accuracy of optical telescope in the past was dominated by the construction of the telescope body and the precision of optical surface. This thesis fits into a larger project with a goal of controlling a flexible telescope in order to help a cheaper telescope achieve higher accuracy. In order to understand the internal motion of telescope, the goal of this thesis is to build a state space model of a two-degree-of-freedom telescope using a known star location as feedback. The model presented in this thesis may be used for the telescope simulation and the control design in the future. …

Sae Baja: Final Drive Gearbox, Michael Mccausland, Michael Watkins, Ian Masterson, Andrew Sommer

Mechanical Engineering

This paper presents the results of a manual transmission project for SAE Baja. A full engineering process is documented, including problem definition, scheduling, conceptualization, decision theory, synthesis, analysis, manufacturing, and testing. A comparison is made between existing and potential mechanical power train solutions. The final design is analyzed in dynamic simulations, AGMA stress, predicted FFT spectrums, and shifting rod buckling. A number of complicated parts are manufactured through investment casting and direct CNC machining. Issues in the final assembly have prevented the project from being fully realized, recommendations are made for future SAE Baja teams.

Differential Regulation Of Immature Articular Cartilage Compressive Moduli And Poisson’S Ratios By In Vitro Stimulation With Igf-1 And Tgf-Β1, Gregory M. Williams, Kristin J. Dills, Christian R. Flores, Michael E. Stender, Kevin M. Stewart, Lauren M. Nelson, Albert C. Chen, Koichi Masuda, Scott J. Hazelwood, Stephen M. Klisch, Robert L. Sah

Mechanical Engineering

Mechanisms of articular cartilage growth and maturation have been elucidated by studying composition-function dynamics during in vivo development and in vitro culture with stimuli such as insulin-like growth factor-1 (IGF-1) and transforming growth factor-beta 1 (TGF-β1). This study tested the hypothesis that IGF-1 and TGF-β1 regulate immature cartilage compressive moduli and Poisson’s ratios in a manner consistent with known effects on tensile properties. Bovine calf articular cartilage from superficial-articular (S) and middle-growth (M) regions were analyzed fresh or following culture in medium with IGF-1 or TGF-β1. Mechanical properties in confined (CC) and unconfined (UCC) compression, cartilage matrix composition, and explant …

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 …

Testing The Test: Validity And Reliability Of Senior Exit Exam, Lizabeth Schlemer, Daniel Waldorf

Industrial and Manufacturing Engineering

A senior exit exam is considered an excellent direct measure of student learning for ABET assessment, but the usefulness of the information gathered is related to the validity and reliability of the test itself. The Industrial and Manufacturing Engineering Department at California Polytechnic State University, San Luis Obispo has used a content exam for several years. This paper will discuss test development, administration, and the role it plays in the assessment process. In addition, the test is evaluated using the standard psychometric techniques of reliability and validity. The results of the evaluation are used to refine the test. The importance …

Development And Assessment Of A Pcb Layout And Manufacturong Laboratory Module In Introductory Electric Circuits For Ee And Non-Ee Majors, Albert Liddicoat, Jianbiao Pan, James G. Harris, Gary Perks, Linda Shepherd

Industrial and Manufacturing Engineering

In standard introductory electric circuits laboratories for electrical engineering (EE) majors and non-EE majors, prototype boards are typically used to construct and test electric circuits. Students typically do not learn how to design and manufacture Printed Circuit Boards (PCB) that are commonly used in more sophisticated design projects and other engineering applications. This paper will present the development and assessment of a PCB layout and manufacturing laboratory module that has been used in introductory electric circuits laboratories for EE and non-EE majors. The feasibility of integrating the new PCB layout and manufacturing module into the electric circuit course will be …

Assessing Curriculum Improvement Through Senior Projects, Jianbiao Pan, Albert Liddicoat, James G. Harris, Linda Shepherd

Industrial and Manufacturing Engineering

Senior project and/or capstone design courses are intended to provide a culminating design experience for students and to demonstrate their understanding of engineering knowledge and their ability to apply that knowledge to practical problems. It is expected that the quality and attributes of students’ senior design projects can be used as a good measure of determining how well the curriculum prepares students to engage in engineering design as well as a measure of faculty teaching and student learning. This paper reports the results of a study designed to assess whether the new computer engineering curriculum implemented at Cal Poly over …

Ground Support Equipment For Northrop Grumman Massive Heat Transfer Experiment, Michael A. Manuel, Christopher J. Sparber, Greg A. Trent

Aerospace Engineering

California Polytechnic State University students designed, built, and certified ground support equipment for the Northrop Grumman Massive Heat Transfer Experiment. The Cal Poly design team built the 10000, 20000, and 30000 assemblies to meet Northrop Grumman requirements. The requirements included interface limitations, design load factors, delivery, and testing specifications. The design process consists of requirements generation, conceptual design, preliminary design, design reviews, manufacturing, and certification. The hardware was successfully completed and is used at the Johnson Space and Kennedy Space Center.

Irrigation Leak Detection: Using Flow Rate Sensors To Detect Breaks In An Irrigation System, Adam Openshaw, Kalvin Vu

Computer Engineering

This report details the exploration and invention of a mechanism that can detect breaks in an irrigation system. With the ultimate goal of conserving water, we have designed an inexpensive, self sustaining flow rate monitor that can be used to identify anomalies in an irrigation system and wirelessly communicate the status of the system to a base station. Our implementation can also determine the direction of the anomaly based on the nature of the anomaly itself. This means that multiple monitors can be used to pinpoint the location of a break within the system in addition to merely detecting its …

The Applications And Limitations Of Printable Batteries, Matthew Delmanowski

Graphic Communication

This study focuses on the potential applications for printed batteries and how they could affect the printing industry. It also analyzes the main problems associated with manufacturing this technology and what needs to be done to overcome these issues. To find the answers to these questions, two methods of research were used. The first was through the elite and specialized interviewing of Dr. Scott Williams of Rochester Institute of Technology and Professor Nancy Cullins from Cal Poly. The second form of research was a common, yet useful, method called secondary research. This entailed looking at recent written research papers about …