Structures and Materials Commons^™

Deployable Antenna For Cubesat, Mackenzie Thomas Lennon, Caleb Andrew Barber, David Matthew Galves

Mechanical Engineering

This project is a proof-of-concept ground model of a large deployable antenna designed for the small space requirements of CubeSats. This small deployment module is designed to fit a 2 m by 1 m reflective antenna inside a storage volume of with the dimensions 20 cm by 20 cm x 40 cm. The reflector will be deployed to a parabolic shape with the goal of modeling the reflector necessary for high frequency communication. Because this module is designed as a proof-of-concept for the deployable parabolic reflector specifically, no electrical components will be incorporated and will just focus on the deployment …

Study Of Knowledge-Based System (Kbs) And Decision Making Methodologies In Materials Selection For Lightweight Aircraft Metallic Structures, Pashupati R. Adhikari, Reza Mirshams

Journal of Applied Science & Engineering Technology

This paper presents an overview of knowledge-based system (KBS) in the context of decision making methodologies used in materials selection for the design of light weight aircraft metallic structures. Overall aircraft weight reduction means substantially less fuel consumption and better efficiency. Part of the solution to this problem is to find a way to reduce overall weight of metallic structures in the aircraft. Two distinct multiple criteria decision making (MCDM) methodologies are presented with examples featuring a set of short-listed materials suitable in the design of the structures. Pre-defined constraint values, mainly mechanical properties, are employed as relevant attributes satisfying …

Integration Of Macro-Fiber Composite Material On A Low Cost Unmanned Aerial System, May Chong Chan

Doctoral Dissertations and Master's Theses

The development, deployment, and operation of Unmanned Aerial Systems (UAS) have grown exponentially in recent years and have provided researchers with the opportunity to gain hands-on experience with aircraft in a manner that was previously limited to institutions and companies with large budgets. This allows the generation and testing of UAS advanced technologies using low cost systems. The scope of this thesis does not aim to make vast improvements to the control strategy itself, but to expand upon previous UAV work carried out at Embry-Riddle by designing, implementing, and demonstrating a simulation environment for mechanical and Macro-Fiber Composite (MFC) actuated …

Study Of Custom Tool Control In Aviation And Aerospace And Selection Of Materials And Manufacturing Process, Ethan C. Rowley

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Business and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Ethan C. Rowley on April 27, 2017.

Powered-Lift Aircraft Category: What Is It?, Nihad E. Daidzic

Aviation Department Publications

FAA Safety Seminar (GL1574995) held at Minnesota State University, Mankato at 18:00 CST on Thursday, April 6, 2017.

Investigating The Potential Of Using Off-Axis 3d Woven Composites In Composite Joints’ Applications, Mohamed Nasr Saleh, Ying Wang, Arief Yudhanto, Adam Joesbury, Prasad Potluri, Gilles Lubineau, Constantinos Soutis

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The effect of circular notch has been evaluated for three different architectures of three-dimensional (3D) carbon fiber woven composites (orthogonal, ORT; layer-to-layer, LTL; angle interlock, AI) through open-hole quasi-static tension and double-lap bearing strength tests in the off-axis (45°) direction. Damage characterization is monitored using Digital Image correlation (DIC) for open-hole testing and X-ray Computed Tomography (CT) for double-lap bearing strength test. The off-axis notched 3D woven composites exhibit minor reduction (less than 10 %) of the notched strength compared to the un-notched strength. DIC strain contour clearly show stress/strain localization regions around the hole periphery and stress/strain redistribution away …

Stressed Oxidation Of Hafnium Diboride In Air At 1500°C, Thomas A. Bowen

Theses and Dissertations

Hypersonic vehicles with narrow airfoils produce thin boundary layers and shock temperatures in excess of 2000°C, exceeding the operating limits of traditional aerospace materials. The use of ultra-high temperature ceramics (UHTCs) allows for operating temperatures far exceeding those of metallic alloys. One such UHTC is hafnium diboride (HfB₂). Transition metal diborides generally experience significant oxidation degradation at elevated temperatures. The use of additives, such as silicon carbide (SiC) has been shown to reduce the oxidation of transition metal diborides. This research focused on the compressive creep of HfB₂ with varying amounts of SiC in air at 1500°C. …

Fatigue Behavior Of An Advanced Melt-Infiltrated Sic/Sic Composite At 1200°C In Air And In Steam, Nicholas J. Boucher

Theses and Dissertations

The tension-tension fatigue behavior of an advanced melt-infiltrated (MI) silicon carbide/silicon carbide (SiC/SiC) ceramic matrix composite (CMC) was investigated at 1200 degrees Celsius in air and in steam. The MI composite consisted of ten 0/90 plies of Hi-Nicalon-S SiC fibers woven in a five harness satin weave (5HSW), a CVI BN interphase to provide a weak fiber-matrix interphase, and a CVI SiC matrix layer followed by infiltration with SiC particulate slurry and molten silicon. Nine tensile specimens of the material were used in a pilot investigation of mechanical performance at elevated temperature. One specimen was used in a monotonic tensile …

The Effect Of Biocomposite Material In A Composite Structure Under Compression Loading, Benjamin Andrew Sweeney

Master's Theses

While composite structures exhibit exceptional strength and weight saving possibilities for engineering applications, sometimes their overall cost and/or material performance can limit their usage when compared to conventional structural materials. Meanwhile ‘biocomposites’, composite structures consisting of natural fibers (i.e. bamboo fibers), display higher cost efficiency and unique structural benefits such as ‘sustainability’. This analysis will determine if the integration of these two different types of composites are beneficial to the overall structure. Specifically, the structure will consist of a one internal bamboo veneer biocomposite ply; and two external carbon fiber weave composite plies surrounding the bamboo biocomposite. To acquire results …

A Multiscale Model For Damage Progression And Detection In Piezo/Pyroelectric Composite Laminates, Yehia Bahei-El-Din, Amany Micheal

Centre for Advanced Materials

Assessment of damage initiation and progression in composite structures reinforced with electrically active filaments is modelled in a multiscale analysis. The analysis developed is a two-tier, interactive analysis, which involves two length scales; macroscopic, and microscopic. The proposed multiscale analysis provides seamless integration of the mechanics at the two length scales, including piezoelectric and pyroelectric coupling effects and damage under overall thermomechanical loads and an electric field applied to electroactive fibers. The macromechanical analysis is performed for multidirectional, fibrous laminates using the lamination theory, including bending, and the micromechanical analysis is performed using a two-phase model and a periodic array …

Detecting Laminate Damage Using Embedded Electrically Active Plies – An Analytical Approach, Amany Micheal, Yehia Bahei-El-Din

Centre for Advanced Materials

Assessment of damage initiation and progression in composite laminates with embedded electrically active plies is modeled. Utilizing electrically active layers embedded in composite laminates as damage sensors is proposed by several researchers and is mainly assessed experimentally. Sensing damage using embedded electrically active plies is generally preferred over the use of surface mounted PZT wafers since the range of the latter is limited to a very narrow area underneath the surface, while multiple damage mechanisms can generally be found in several plies of the laminate. The solution presented invokes two levels of analysis. Firstly, on the laminate level, applied membrane …

Weather Balloon Payload Box, Shellbie Liberty

All Undergraduate Projects

A payload box holding a self-rotating camera was constructed to go on a weather balloon that will document the upcoming solar eclipse on August 21, 2017. A group of physics students, and the paper’s author, are working under Dr. Darci Snowden on the CWU Near Space Observation Team for research dedicated to the eclipse in Oregon. Various projects, including the payload box, are being designed to go up on a high altitude weather balloon. The payload box was designed and constructed to withstand the impact force of falling from 120,000 ft. This was done so the box could be reusable …

Measuring Space Radiation Shielding Effectiveness, Amir Bahadori, Edward Semones, Michael Ewert, James Broyan, Steven Walker

Mathematics & Statistics Faculty Publications

Passive radiation shielding is one strategy to mitigate the problem of space radiation exposure. While space vehicles are constructed largely of aluminum, polyethylene has been demonstrated to have superior shielding characteristics for both galactic cosmic rays and solar particle events due to the high hydrogen content. A method to calculate the shielding effectiveness of a material relative to reference material from Bragg peak measurements performed using energetic heavy charged particles is described. Using accelerated alpha particles at the National Aeronautics and Space Administration Space Radiation Laboratory at Brookhaven National Laboratory, the method is applied to sample tiles from the Heat …

Analytical Strip Method For Thin Cylindrical Shells, John T. Perkins

Theses and Dissertations--Civil Engineering

The Analytical Strip Method (ASM) for the analysis of thin cylindrical shells is presented in this dissertation. The system of three governing differential equations for the cylindrical shell are reduced to a single eighth order partial differential equation (PDE) in terms of a potential function. The PDE is solved as a single series form of the potential function, from which the displacement and force quantities are determined. The solution is applicable to isotropic, generally orthotropic, and laminated shells. Cylinders may have simply supported edges, clamped edges, free edges, or edges supported by isotropic beams. The cylindrical shell can be stiffened …

Cubesat Adcs Validation And Testing Apparatus, Jacob Stevens

Honors Theses

The WALI team at Western Michigan University requested a test environment to validate their CubeSat’s de-tumbling control system and hardware. The test environment required a Helmholtz cage and spherical air bearing. The Helmholtz cage provides an adjustable magnetic field to simulate low earth orbit; the spherical air bearing simulates the friction free environment the CubeSat will experience in space. In conjunction, the two components create an adjustable system that simulates a satellite in low earth orbit.

Nanostructured Morphologies In Glassy Polymer Networks, Brian Greenhoe

Dissertations

The body of this work describes a novel approach for the dispersion of multi-walled carbon nanotubes in a high T_g epoxy prepolymer matrix using a twin screw high-shear continuous reactor. The method demonstrated improves on previous dispersion methods in several ways. It offers increased efficiency through excellent heat transfer, while being solvent-less, scale-able, and tailorable to drive dispersion states to judiciously chosen dispersion states. Furthermore, it was shown that dispersion state and agglomerate morphology can be directed, in several ways, through processing conditions and also by controlling the matrix viscosity profile through cure. Broadband dielectric spectroscopy, optical hot-stage microscopy, …

Performance Characterization Of Ceramic Matrix Composites Through Uniaxial Monotonic Tensile Testing, Jóhannes Pétursson

Doctoral Dissertations and Master's Theses

Ceramic matrix composite (CMC) samples were tested in order to characterize their mechanical performance and provide metrics for material process refinement and component design. Monotonic, uniaxial tensile testing of an uncoated carbon fiber reinforced silicon carbide ceramic at room temperature was performed following ASTM standard C1275 to measure ultimate tensile strength and elastic modulus. Equipment verification was carried out through alignment measurement with a gaged tensile specimen using ASTM E1012 to ensure the monotonic nature of the testing equipment. Tensile strength data was treated with Weibull statistical models to produce A and B-basis strength properties for design values.

An alternative …

Windshield Defrost And Deice Using Carbon Nanotube Composite, Santhosh Kumar Loganathan

Doctoral Dissertations and Master's Theses

Carbon nanotubes (CNT) are well known for their high thermal and electrical conductivities and can offer a great advantage by converting the applied electrical energy into instant heat with minimum energy loss. The goal of this research is to develop a very thin CNT layer sandwiched between two layers of glass substrate in order to generate instant heat through electrodes. The thin CNT layer is fabricated using the CNTRENETM solution, which is a mixture of single-walled nanotubes (SWNTs) (~75%), double-walled nanotubes (DWNTs), and multi-walled nanotubes (MWNTs) with an average CNT length of ~0.4 - 0.6 μm. The thin layer is …

Development Of Cal Poly's Shock Table, Christopher D. Risner

Master's Theses

Shock is one of the environmental tests that a spacecraft must pass before being cleared for launch. Shock testing poses a challenging data acquisition issue and careful selection of equipment is crucial to creating a successful shock test facility. Cal Poly’s CubeSat programs can currently perform all environmental testing other than shock themselves, so a quality shock table would be useful. Previous groups of students had developed a shock table, and this paper details the improvement and characterization of that shock table’s behavior. Several adjustable parameters were tested and documented to discover trends in the shock table’s response to an …

Effects Of The Cooling Rate On The Shear Behavior Of Continuous Glass Fiber/Impact Polypropylene Composites (Gf-Ipp), H. Wafai, G. Lubineau, A. Yudhanto, M. Mulle, W. Schijve, N. Verghese

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Fiber-reinforced composites with improved dissipation of energy during impact loading have recently been developed based on a polypropylene copolymer commonly called impact polypropylene (IPP). Composites made of IPP reinforced with glass fibers (GF) are particularly attractive to the automotive industry due to their low cost and good impact resistance. In such composites, the cooling rate varies depending on processing techniques and manufacturing choices. Here, we study the effects of the cooling rate of GF-IPP composites on shear behavior, which is critical in impact applications, using [±45]s monotonic and cyclic (load/unload) tensile specimens. The specimens were manufactured under a wide range …

Finite Element Simulation Of Pzt-Aided Interrogation Of Composite Laminates Exhibiting Damage, Amany Micheal, Yehia Bahei-El-Din

Centre for Advanced Materials

Piezoelectricity has proved effective in capturing changes in structures caused by various damage mechanisms. In one approach, piezoelectric wafer active sensors (PWAS) are mounted on the surface of the host structure and utilized as both actuators and sensors to interrogate the structure and monitor its health. This is achieved by subjecting the PWAS to a transient electric pulse and reading the resulting voltage. Changes in the stiffness of the substrate due to structural damage affect the response of the PWAS, which could be correlated to integrity of the structure. Applying this technique to fibrous composite laminates encounters particular challenges due …

Characterising The Loading Direction Sensitivity Of 3d Woven Composites: Effect Of Z-Binder Architecture, Mohamed Nasr Saleh, Arief Yudhanto, Prasad Potluri, Gilles Lubineau, Constantinos Soutis

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Three different architectures of 3D carbon fiber woven composites (orthogonal, ORT; layer-to-layer, LTL; angle interlock, AI) were tested in quasi-static uniaxial tension. Mechanical tests (tensile in on-axis of warp and weft directions as well as 45° off-axis) were carried out with the aim to study the loading direction sensitivity of these 3D woven composites. The z-binder architecture (the through-thickness reinforcement) has an effect on void content, directional fiber volume fraction, mechanical properties (on-axis and off-axis), failure mechanisms, energy absorption and fiber rotation angle in off-axis tested specimens. Out of all the examined architectures, 3D orthogonal woven composites (ORT) demonstrated a …

Simulation Investigation Of Temperature Distribution In Large Aluminium Panel During Autoclave Age Forming Process, Yongqian Xu

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Multi-Dome Forming Of A Ti–Al–Mn Alloy, Sergey Aksenov, Aleksey Kolesnikov, Ivan Zakhariev

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Large Linear Magnetoresistance In Heavily-Doped Nb:Srtio3 Epitaxial Thin Films, Hyunwoo Jin, Keundong Lee, Seung-Hyub Baek, Jin-Sang Kim, Byung-Ki Cheong, Bae Ho Park, Sungwon Yoon, B. J. Suh, Changyoung Kim, Sung S. Ambrose Seo, Suyoun Lee

Physics and Astronomy Faculty Publications

Interaction between electrons has long been a focused topic in condensed-matter physics since it has led to the discoveries of astonishing phenomena, for example, high-T_c superconductivity and colossal magnetoresistance (CMR) in strongly-correlated materials. In the study of strongly-correlated perovskite oxides, Nb-doped SrTiO₃ (Nb:SrTiO₃) has been a workhorse not only as a conducting substrate, but also as a host possessing high carrier mobility. In this work, we report the observations of large linear magnetoresistance (LMR) and the metal-to-insulator transition (MIT) induced by magnetic field in heavily-doped Nb:STO (SrNb_0.2Ti_0.8O₃) epitaxial thin …

Mechanical Properties And Fatigue Behavior Of Unitized Composite Airframe Structures At Elevated Temperature, Mohamed Noomen

Theses and Dissertations

The tension-tension fatigue behavior of a newly developed unitized composite material system was investigated. The unitized composite consisted of a polymer matrix composite (PMC) co-cured with a ceramic matrix composite (CMC). The PMC portion consisted of an NRPE high-temperature polyimide matrix reinforced with carbon fibers woven in an eight harness satin weave (8HSW). The CMC layer is a single-ply non-crimp 3D orthogonal weave composite consisting of ceramic matrix reinforced with glass fibers. In order to assess the performance and suitability of this composite for use in aerospace components designed to contain high-temperature environments, mechanical tests were performed under temperature conditions …

From Xst To F-117a, Alan Brown

ERAU Prescott Aviation History Program

Learn the remarkable story of stealth technology from the man often referred to as “Mr. Stealth.” From 1975-1989 Alan Brown was a member of Lockheed “Skunk Works”, becoming program manager & chief engineer for the F-117A Stealth Fighter from initial concept until the first production aircraft was built, 1978 to 1982. Hear the inside story of the many challenges faced by the stealth program and how they were solved.

Experimentation Of Mode I And Mode Ii Fracture Of Uni-Directional Composites And Finite Element Analysis Of Mode I Fracture Using Cohesive Contact, Joseph Daniel Garrett

Master's Theses

As the use of fiber-reinforced composites has increased over the decades, so has the need to understand the complexity of their failure mechanisms as engineers seek to improve the damage tolerance of composite laminated structures. One of the most prevalent and limiting mode of failure within composite laminates is delamination, since it not only reduces a structures stiffness and strength, but can be very difficult to detect without the use of special non-destructive equipment. Industry testing organizations have utilized several fracture tests in order to characterize the fracture toughness of composite materials under different loading conditions. For this research, ASTM …

Evaluation Of Strain Distortion Correction Protocol Using Scanning Electron Microscopy And Digital Image Correlation, Alexandra Mallory, Alberto Mello, Michael Sangid

The Summer Undergraduate Research Fellowship (SURF) Symposium

Scanning electron microscopy in combination with digital image correlation (SEM-DIC) is a useful technique for measuring strain in materials at the micro-scale. In particular, it can be used to identify micro-scale strain localizations that are the precursor to material failure. While SEM produces high resolution images of the microstructure, the images also contain a large amount of distortion that, during DIC, will result in distorted strain values that require correction. In this project, a nickel-based alloy underwent cyclic mechanical fatigue at three different high temperatures to a targeted maximum strain. Scanning electron microscopy imaging was done on a 200x150μm area …

Metamodels Of Residual Stress Buildup For Machining Process Modeling, Stuart B. Mccrorie, Michael Sangid

The Summer Undergraduate Research Fellowship (SURF) Symposium

In the process of machining materials, stresses, called residual stresses, accumulate in the workpiece being machined that remain after the process is completed. These residual stresses can affect the properties of the material or cause part distortion, and it is important that they be calculated to prevent complications from arising due to the residual stresses. However, these calculations can be incredibly computationally intensive, and thus other methods are needed to predict the residual stresses in materials for quick decision-making during machining. By using metamodels - a method of representing data where few data points exist - we can achieve an …