Mechanical Engineering Commons^™

Vibration Analysis Of Healthy Skin: Toward A Noninvasive Skin Diagnosis Methodology, Rakshita Panchal, Luke Horton, Peyman Poozesh, Javad Baqersad, Mohammadreza Nasiriavanaki

Mechanical Engineering Publications

Several noninvasive imaging techniques have been developed to monitor the health of skin and enhance the diagnosis of skin diseases. Among them, skin elastography is a popular technique used to measure the elasticity of the skin. A change in the elasticity of the skin can influence its natural frequencies and mode shapes. We propose a technique to use the resonant frequencies and mode shapes of the skin to monitor its health. Our study demonstrates how the resonant frequencies and mode shapes of skin can be obtained using numerical and experimental analysis. In our study, natural frequencies and mode shapes are …

Recent Advances In Piezoelectric Wafer Active Sensors For Structural Health Monitoring Applications, Hanfei Mei, Mohammad Faisal Haider, Roshan Prakash Joseph, Asaad Migot, Victor Giurgiutiu

Faculty Publications

In this paper, some recent piezoelectric wafer active sensors (PWAS) progress achieved in our laboratory for active materials and smart structures (LAMSS) at the University of South Carolina: http: //www.me.sc.edu/research/lamss/ group is presented. First, the characterization of the PWAS materials shows that no significant change in the microstructure after exposure to high temperature and nuclear radiation, and the PWAS transducer can be used in harsh environments for structural health monitoring (SHM) applications. Next, PWAS active sensing of various damage types in aluminum and composite structures are explored. PWAS transducers can successfully detect the simulated crack and corrosion damage in aluminum …

Design Of Vibration Class Laboratory Assignments: Focusing On Broader Application, Ethan Wayne Cating

Graduate Theses - Mechanical Engineering

Courses in vibration taught at Rose-Hulman Institute of Technology are designed to blend classroom discussion of the science of vibration with practical, hands-on applications. The laboratory portion of the undergraduate course in vibration focuses on two areas: (1) system identification for single- and multi-degree-of-freedom systems in the frequency domain through sine-sweep shake testing; and (2) identifying natural frequencies and mode shapes for continuous systems via experimental modal analysis using frequency response data collected through a roving hammer test. Modal analysis is performed using an in-house MATLAB-based program known as Easy Modal Analysis Program (EMAP). The goals of this thesis are …

Application Of Artificial Neural Networks To Assess Student Happiness, Gokhan Egilmez, Nadiye O. Erdil, Omid Mohammadi Arani, Mana Vahid

Mechanical and Industrial Engineering Faculty Publications

The purpose of this study is to develop an analytical assessment approach to identify the main factors that affect graduate students' happiness level. The two methods, multiple linear regression (MLR) and artificial neural networks (ANN), were employed for analytical modelling. A sample of 118 students at a small non-profit private university constituted the survey pool. Various factors including education, school facilities, health, social activities, and family were taken into consideration as a result of literature review in happiness assessment. A total of 32 inputs and one output variables were identified during survey design phase. The following survey conduction, data collection, …

The Effect Of Cryogenic Thermal Cycling On Aging, Rejuvenation, And Mechanical Properties Of Metallic Glasses, Nikolai V. Priezjev

Mechanical and Materials Engineering Faculty Publications

The structural relaxation, potential energy states, and mechanical properties of a model glass subjected to thermal cycling are investigated using molecular dynamics simulations. We study a non-additive binary mixture which is annealed with different cooling rates from the liquid phase to a low temperature well below the glass transition. The thermal treatment is applied by repeatedly heating and cooling the system at constant pressure, thus temporarily inducing internal stresses upon thermal expansion. We find that poorly annealed glasses are relocated to progressively lower levels of potential energy over consecutive cycles, whereas well annealed glasses can be rejuvenated at sufficiently large …

Ignition And Extinction Behavior Of Fuels In A Microcombustor, Pawan Sharma

LSU Doctoral Dissertations

Conventional fuel testing device-CFR engine requires large quantities of fuels, which makes it unsuitable for research of small samples of fuels. This current study seeks to address this limitation by using an externally heated microcombustor as an alternative fuel testing device. Mainly three combustion behaviors have been observed inside a microcombustor: strong flames at higher flow rates, Flames with Repetitive Extinction and Ignition (FREI) at intermediate flow rates, and weak flames at marginal flow rates. In previous studies, weak combustion behavior has been proven suitable to study fuel properties from small samples of fuels. Microcombustor experiments typically rely on flame …

Propagating, Evanescent, And Complex Wavenumber Guided Waves In High-Performance Composites, Victor Giurgiutiu, Mohammad Faisal Haider

Faculty Publications

The study of propagating, evanescent and complex wavenumbers of guided waves (GWs) in high-performance composites using a stable and robust semi-analytical finite element (SAFE) method is presented. To facilitate understanding of the wavenumber trajectories, an incremental material change study is performed moving gradually from isotropic aluminum alloy to carbon fiber reinforced polymer (CFRP) composites. The SAFE results for an isotropic aluminum alloy plate are compared with the exact analytical solutions, which shows that N = 20 SAFE elements across the thickness provides

Achieving Superelasticity In Additively Manufactured Niti In Compression Without Post-Process Heat Treatment, Narges Shayesteh Moghaddam, Soheil Saedi, Amirhesam Amerinatanzi, Alejandro Hinojos, Ali Ramazani, Julia Kundin, Michael J. Mills, Haluk E. Karaca, Mohammad Elahinia

Mechanical Engineering Faculty Publications

Shape memory alloys (SMAs), such as Nitinol (i.e., NiTi), are of great importance in biomedical and engineering applications due to their unique superelasticity and shape memory properties. In recent years, additive manufacturing (AM) processes have been used to produce complex NiTi components, which provide the ability to tailor microstructure and thus the critical properties of the alloys, such as the superelastic behavior and transformation temperatures (TTs), by selection of processing parameters. In biomedical applications, superelasticity in implants play a critical role since it gives the implants bone-like behavior. In this study, a methodology of improving superelasticity in Ni-rich NiTi components …

Fabrication And Characterization Of Centrifugally Spun Poly(Acrylic Acid) Nanofibers, David De La Garza, Francisco De Santiago, Luis Materon, Mircea Chipara, Mataz Alcoutlabi

Mechanical Engineering Faculty Publications

The production of poly(acrylic acid) (PAA) nanofibers by the centrifugal spinning of PAA solutions in water is reported. The effect of the spinneret rotational speed and concentration of PAA solutions on the diameter of nanofibers and on their quality (assessed by the absence of beads) is discussed. The main physical properties of PAA such as glass-transition temperature (Tg) are studied in detail and compared to the feature of the as-received homopolymer. It is shown that the glass-transition temperature of the bulk PAA and PAA nanofibers (as measured by differential scanning calorimetry) depends on the heating rate according …

A Sine-Summation Algorithm For The Prediction Of Ship Deck Motion, Christian R. Bolander, Douglas F. Hunsaker

Mechanical and Aerospace Engineering Student Publications and Presentations

Landing a fixed-wing aircraft on a moving aircraft carrier is a risky and inefficient process. Having an accurate prediction of ship deck motion decreases the risk posed to both the pilot and the aircraft and increases the efficiency of landing maneuvers. The present work proposes the use of a sine-summation algorithm to predict future ship motion. The algorithm decomposes recorded ship acceleration data into its characteristic harmonic parameters using a fast Fourier transform. The harmonic parameters are then used in a summation of sine waves to create a fit for the acceleration data, which is projected into future time intervals …

Structural Transformations During Periodic Deformation Of Low-Porosity Amorphous Materials, Nikolai V. Priezjev, Maxim A. Makeev

Mechanical and Materials Engineering Faculty Publications

Atomistic simulations are employed to study structural evolution of pore ensembles in binary glasses under periodic shear deformation with varied amplitude. The consideration is given to porous systems in the limit of low porosity. The initial ensembles of pores are comprised of multiple pores with small sizes, which are approximately normally distributed. As periodic loading proceeds, the ensembles evolve into configurations with a few large-scale pores and significantly reduced number of small pores. These structural changes are reflected in the skewed shapes of the pore-size distribution functions and the appearance of a distinct peak at large length scales after hundreds …

Optimizing 3d Printed Prosthetic Hand And Simulator, Stephen Estelle

LMU Theses and Dissertations

The purpose of this study is to examine the position and use of an upper extremity prosthetic simulator on non-amputees. To see how a 3D printed prosthetic simulator can be optimized to serve the user correctly and accurately. In addition, this study examines the improvement of the Hosmer 5X Prosthetic Hook with the addition of newly designed trusses on to the prosthetic, as well as utilizing a new manufacturing method known as 3D printing. These topics are important because there is no standardized prosthetic simulator for schools and research facilities to use. Off the shelf prosthetic simulator cost upwards of …

Comprehensive Parameters Identification And Dynamic Model Validation Of Interior-Mount Line-Start Permanent Magnet Synchronous Motors, Luqman S. Maraaba, Zakariya M. Al-Hamouz, Absulaziz S. Milhem, Ssennoga Twaha

School of Technology Publications

The application of line-start permanent magnet synchronous motors (LSPMSMs) is rapidly spreading due to their advantages of high efficiency, high operational power factor, being self-starting, rendering them as highly needed in many applications in recent years. Although there have been standard methods for the identification of parameters of synchronous and induction machines, most of them do not apply to LSPMSMs. This paper presents a study and analysis of different parameter identification methods for interior mount LSPMSM. Experimental tests have been performed in the laboratory on a 1-hp interior mount LSPMSM. The measurements have been validated by investigating the performance of …

A Procedure For The Calculation Of The Perceived Loudness Of Sonic Booms, Christian R. Bolander, Douglas F. Hunsaker, Hao Shen, Forrest L. Carpenter

Mechanical and Aerospace Engineering Student Publications and Presentations

Implementing a method to calculate the human ear’s perceived loudness of a sonic boom requires consulting scattered literature with varying amounts of detail. This work describes a comprehensive implementation of Stevens’ Mark VII in Python, called PyLdB. References to literary works are included in enough detail so that the reader could use this work as a guide to implement the Mark VII algorithm. The details behind the mathematics of the Mark VII algorithm are included and PyLdB is used to calculate the perceived loudness of an example pressure signature. PyLdB is benchmarked against a widely used and validated code by …

Mechanical Engineering News, Georgia Southern University

Mechanical Engineering: News & Publications (2013-2023)

• ME Undergraduate Awarded Scholarship from Alliance of Hazardous Materials Professionals

Mechanical Engineering Technology Newsletter 2019, Department Of Manufacturing And Mechanical Engineering Technology, Michigan Technological University

Department of Manufacturing and Mechanical Engineering Technology Newsletters

Table of Contents

• Where Racing Will Take Him
• Irwin Wins Center for Teaching and Learning Instructional Award
• Five MET Students Inducted into Epsilon Pi Tau Honor Society
• 2018 and 2019 Scholarship Awards
• 2018 Bob Mark Business Model Competition
• Senior Design Projects
• What's New?

Computationally Efficient, Multi-Domain Hybrid Modeling Of Surface Integrity In Machining And Related Thermomechanical Finishing Processes, Julius M. Schoop, David Adeniji, Ian S. Brown

Mechanical Engineering Faculty Publications

In order to enable more widespread implementation of sophisticated process modeling, a novel, rapidly deployable multi-physics hybrid model of surface integrity in finishing operations is proposed. Rather than modeling detailed chip formation mechanics, as is common in numerical models, the proposed models integrates existing analytical and semi-empirical models of the plastic, elastic, thermal and thermodynamic domains. Using this approach, highly complex surface integrity phenomena such as residual stresses, grain size, phase composition, microhardness profile, etc. can be accurately predicted in a manner of seconds. It is envisioned that this highly efficient modeling scheme will drive new innovations in surface engineering.

Experimental And Numerical Behavior Of Plain Hybrid Fiber Metal Laminate Composites, Aiea A. Elhabak, Mostafa Shazly, Tarek A. Osman, Aly A. Khattab

Centre for Advanced Materials

This study presents an investigation to the mechanical properties of FML components under static axial and bending loads. Two types of Fiber Metal Laminates (FMLs), namely, FML 1 and 2 were considered in the present research. FML1 contains 4 layers of laminated glass/epoxy laminate while FML 2 contains two aramid fiber laminates that replaced the glass/epoxy laminates and adjacent to the inner metal layer. Experimental stiffness and strength are discussed and compared with the theoretical values. Under bending loads, two different end conditions are considered, free and fixed and the results both ends were compared. Finite Element Analysis (FEA) was …

Mechanical Behavior Of Aluminum Hybrid Laminates, Aiea A. Elhabak, Mostafa Shazly, Tarek A. Osman, Aly A. Khattab

Centre for Advanced Materials

This work has been dedicated to investigating the stiffness and strength of FML components under static axial and bending loads. There are two types of fiber metal laminates (FML) called Al3G4 and Al3G2K2 labeled according to the plate design. Al3G4 is Glare 3/2 -0.4 contains 4 layers of laminated glass/epoxy laminate. Al3G2K2, is a hybrid fiber laminate, has two aramid fiber laminates adjacent to the inner metal layer. Experimental stiffness and strength are discussed and compared with the theoretical data. The relationship between tensile and bending forces is discussed. Referred to the end bending condition, results of free end support …

Rc Baja: Drivetrain, Nick Paulay

All Undergraduate Projects

The American Society of Mechanical Engineers (ASME) annually hosts an RC Baja challenge, testing a RC car in three events: slalom, acceleration and Baja. Although ASME will not be holding an event this year, CWU will be holding an event with three RC Baja car teams from CWU as well as other teams from local colleges. The RC car that is tested in these events is designed and manufactured typically in teams of two. The RC car that each team submits must be able to complete these events to score points. One part of great importance for the RC car …

Feed Control: Composite Recycle, Rosy Perez

All Undergraduate Projects

The Boeing Company gave Central Washington University an opportunity for students to research and come up with an idea to reduce costs and landfill waste caused by the trimmings from the 777x composite wing pieces. The engineering and manufacturing for this project is about transporting composite material through to the delamination and chipper process. The delamination process uses a ram to press two claw shaped devices together that bends and deforms the material in opposite directions. The chipper process uses counter rotating saw blades spaced 1/8” apart to produce small shredded material. It is important for this newly designed feed …

Carbon Fiber Recycler : Fiber Reclaimer, Alexander Edwards

All Undergraduate Projects

Boeing uses composite components for the 777x aircraft. The production of composite parts results in flashing (excess material) that must be trimmed and "thrown away" as scrap. Boeing is investigating means of recycling these scraps. The method proposed for this project is to delaminate and shred the composite material. The delamination process uses a ram to press two claw shaped devices together that bends and deforms the material in opposite directions. The chipper process uses counter rotating saw blades spaced 1/8” apart to produce small shredded material. This shredding material is pyrolyzed (heated) to decay the resin leaving the carbon …

Medallion Manufacturing, Luis Perez

All Undergraduate Projects

A more efficient manufacturing process is needed to create the approximately 30 MET medallions, given to the graduating class. The process must be repeatable, consistent, and efficient. The objective is to create a method that can remain the same year to year, save time, and be repeated by anybody. Two approaches were developed: a casting method, and a machining method involving a computer numerically controlled (CNC) mill. The casting method began with a match plate was developed by attaching 3D printed models and runners to plywood. The design was evaluated before the pour using SolidCast software. Special attention was directed …

Automatic Hydraulic Vehicle Jack – “Auto-Jack” Frame, Nick Stadelman

All Undergraduate Projects

The Automotive Industry faces extreme safety concerns during the vehicle lifting process, how can these safety concerns be mediated for the personals in the automotive industry during this process? A revolutionary vehicle jack (“The Auto-Jack”) was developed to remove all unnecessary safety concerns that are presented to the user during the vehicle lifting process. Removing the user from having to position a standard vehicle jack and/or jack stands underneath the vehicle once the vehicle is lifted will eliminate all safety concerns surrounding user inflicted failure. A hydraulic circuit is used to operate the Auto-Jack, this allows the user to operate …

Composite Recycler: Frame, Alfonso Olivera

All Undergraduate Projects

How can composites be recycled? The Composite Recycler is an ongoing project that started in September 2017. The purpose of this project was to create a machine that will delaminate the composites, cut them, and heat them up to separate the resin from the composites so they can be recycled. A group was put together for the 2018-2019 academic year to further the project as a whole improve the operation of the device. The existing base was used as well as the cutter and the power sources. The upgrades included; a housing to support the transport rollers and changing from …

R/C Mini Baja: Drivetrain, Kyle Aitken

All Undergraduate Projects

A device is needed that can power the back wheels of R/C car and allow it to drive smoothly. This drivetrain also has to transmit power to the axles in an acceptable height range to comply with the frame and suspension. The project was supported by a team member who designed the frame and suspension. The design of this project consists of two sub-assemblies that make up the drive train assembly. The transmission assembly uses gears to convert the rotational speed from the motor to the drive shaft. The gearbox assembly also uses gears and converts the rotational speed from …

Electrathon Vehicle: Electrical Power, Samuel Johnson

All Undergraduate Projects

The Electrathon Vehicle: Electrical Power proposal is an in depth dive into theorizing, constructing and testing the design of an electrical circuit. A breakdown of this report gives an extensive and thorough analysis of the problem. How do you efficiently deliver 1kw/hr of power to an electric motor? The methods used to face this challenge and the results seen after are laid out in this report.

The challenge of competing in the Electrathon Race is delivering power to an electric motor for an entire hour without exceeding 1kW/hr of power. The goal is to travel as much distance in the …

Laboratory Water Distiller Project, Duncan Njunge

All Undergraduate Projects

Abstract

The goal of the water distiller project is to provide purified water to all hospitals and laboratories for daily use. As per WHO standards, purified water is a great necessity in these facilities for DNA sequencing, protein research, among others. Available water is not always clean because it is transported through pipes and can get into contact with organisms thereby causing the spread of waterborne diseases. Water distillation processes remove 99.9% of contaminants and water chemicals like fluorine and calcium to produce pure water. For every use, the distiller mechanism uses an electric current as the source of energy …

Custom Designed Wall Mounted Shop Crane, Bradley Lewis

All Undergraduate Projects

The objective of this project was to design and fabricate a custom wall mounted jib crane to specific, non-standard dimensions. The crane was designed to be industry rated for 2000 pounds, rotate at least 180 degrees, and be designed to have a maximum boom length tailored to the specific installation site. Two potential installation sites and purposes were selected for construction: inside the bay doors of a fabrication shop, intended to transfer large pieces of material to and from a plasma table, and inside a car maintenance garage, intended to lift and remove engines and transmissions from cars.

Design of …

Design, Control, And Optimization Of Robots With Advanced Energy Regenerative Drive Systems, Poya Khalaf

ETD Archive

We investigate the control and optimization of robots with ultracapacitor based regenerative drive systems. A subset of the robot joints are conventional, in the sense that external power is used for actuation. Other joints are energetically self-contained passive systems that use ultracapacitors for energy storage. An electrical interconnection known as the star configuration is considered for the regenerative drives that allows for direct electric energy redistribution among joints, and enables higher energy utilization efficiencies. A semi-active virtual control strategy is used to achieve control objectives. We find closed-form expressions for the optimal robot and actuator parameters (link lengths, gear ratios, …