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Developing Abrasion Test Standards For Evaluating Lunar Construction Materials, Ryan L. Kobrick, David M. Klaus, Kenneth W. Street 2019 University of Colorado Boulder

Developing Abrasion Test Standards For Evaluating Lunar Construction Materials, Ryan L. Kobrick, David M. Klaus, Kenneth W. Street

Ryan L. Kobrick

Operational issues encountered by Apollo astronauts relating to lunar dust were catalogued, including material abrasion that resulted in scratches and wear on spacesuit components, ultimately impacting visibility, joint mobility and pressure retention. Standard methods are being developed to measure abrasive wear on candidate construction materials to be used for spacesuits, spacecraft, and robotics. Calibration tests were conducted using a standard diamond stylus scratch tip on the common spacecraft structure aluminum, Al 6061-T6. Custom tips were fabricated from terrestrial counterparts of lunar minerals for scratching Al 6061-T6 and comparing to standard diamond scratches. Considerations are offered for how to apply standards …


System Architecture Design And Development For A Reusable Lunar Lander, Chad Batten, Camille E. Bergin, Aaron Crigger, Darryl Harris, Gillian Suzanne McGlothin 2019 University of Tennessee, Knoxville

System Architecture Design And Development For A Reusable Lunar Lander, Chad Batten, Camille E. Bergin, Aaron Crigger, Darryl Harris, Gillian Suzanne Mcglothin

Chancellor’s Honors Program Projects

No abstract provided.


Development Of A Multi-Probe Kelvin Scanner Device For Industrially-Relevant Characterization Of Surface-Activated Carbon Fiber Reinforced Thermoplastic Composites, Kirby Simon 2019 Washington University in St. Louis

Development Of A Multi-Probe Kelvin Scanner Device For Industrially-Relevant Characterization Of Surface-Activated Carbon Fiber Reinforced Thermoplastic Composites, Kirby Simon

McKelvey School of Engineering Theses & Dissertations

Carbon fiber reinforced thermoplastic (CFRTP) composites are becoming increasingly attractive materials in manufacturing due to their lightweight nature, mechanical strength, and corrosion resistance. Surface activation of these materials is usually required during processing to increase the bond strength of assemblies (aerospace and automotive industries) or improve adhesion with implants (biomedical industry). Industrially-relevant, nondestructive quality control methods for assessing the activation state of these materials do not currently exist, however. Applying principles discovered through the use of scanning probe microscopy, a multiple-probe Kelvin scanning (MPKS) device has been developed that can assess the uniformity of the activation state of plasma-treated CFRTP …


A Constructal Approach To The Design Of Inflected Airplane Wings, Shanae Powell 2019 Florida International University

A Constructal Approach To The Design Of Inflected Airplane Wings, Shanae Powell

FIU Electronic Theses and Dissertations

Aeroelastic instabilities such as flutter can be accurately captured by state-of-the-art aeroelastic analysis methods and tools. However, these tools and methods fall short in exposing the reasons behind the occurrence of such instabilities. In this research, the constructal law is used to discover the main cause of the variation in the flutter speed and stress distribution for inflected aircraft wings when compared to its uninflected counterpart. This law considers the design as a physics phenomenon and uses an evolutionary flow principle to explain and predict the occurrence of energy flow configurations (i.e. the flow of stresses throughout the structure).

For …


Piezoelectric Sensor Crack Detection On Airframe Systems, Kevin J. Lin 2019 Air Force Institute of Technology

Piezoelectric Sensor Crack Detection On Airframe Systems, Kevin J. Lin

Theses and Dissertations

In 2008, the Department of Defense published a guidebook for a methodology named Condition-Based Maintenance Plus (CBM+) which capabilities include improving productivity, shortening maintenance cycles, lowering costs, and increasing availability and reliability. This push replaces existing inspection criteria, often conducted as non-destructive testing (NDT), with structural health monitoring (SHM) systems. The SHM system addressed utilizes guided Lamb waves generated by piezoelectric wafer active sensors (PWAS) to detect the existence, size, and location of damage from through-thickness cracks around a rivet hole. The SHM field lacks an experiment testing how small changes in receiver sensor distances affect damage detection. In addition, …


Initial Stage Of Fluid-Structure Interaction Of A Celestial Icosahedron Shaped Vacuum Lighter Than Air Vehicle, Dustin P. Graves 2019 Air Force Institute of Technology

Initial Stage Of Fluid-Structure Interaction Of A Celestial Icosahedron Shaped Vacuum Lighter Than Air Vehicle, Dustin P. Graves

Theses and Dissertations

The analysis of a celestial icosahedron geometry is considered as a potential design for a Vacuum Lighter than Air Vehicle (VLTAV). The goal of the analysis is ultimately to understand the initial fluid-structure interaction of the VLTAV and the surrounding airflow. Up to this point, previous research analyzed the celestial icosahedron VLTAV in relation to withstanding a symmetric sea-level pressure applied to the membrane of the structure. This scenario simulates an internal vacuum being applied in the worst-case atmospheric environmental condition. The next step in analysis is to determine the aerodynamic effects of the geometry. The experimental setup for obtaining …


W&B Problems For Far/Cs 25 Airplanes Tutorial, Nihad E. Daidzic 2019 Minnesota State University, Mankato

W&B Problems For Far/Cs 25 Airplanes Tutorial, Nihad E. Daidzic

Aviation Department Publications

Weight and Balance (W&B) computations are essential step in ensuring that the aircraft (in this case FAR/CS 25 Transport-category airplanes) is properly loaded with its Center of Mass (CM) of Center of Weight/Gravity (CG) in the proper range.


Educating The Space Scientists At Embry-Riddle Through Design, Build And Fly Rocketry Experience, Pedro Llanos, Robert E. Haley, Sathya Gangadharan 2019 Embry-Riddle Aeronautical University - Daytona Beach

Educating The Space Scientists At Embry-Riddle Through Design, Build And Fly Rocketry Experience, Pedro Llanos, Robert E. Haley, Sathya Gangadharan

Pedro J. Llanos (www.AstronauticsLlanos.com)

Practical experience for students in rockets and payloads is very valuable in the space industry, and it is something that would give them an advantage over other applicants. Students in Embry-Riddle Aeronautical University’s Payload and Integration class were given the opportunity to build a level 1 rocket and gain experience developing, testing, and integrating payloads into a rocket. The students were given the tasks to come up with an idea for a payload, design the payload to fit within the rocket for flight, and assemble and launch the rocket with the payload in the payload bay. The tasks required for …


Composite Recycler: Delamination, Nathan Sauer 2019 Central Washington University

Composite Recycler: Delamination, Nathan Sauer

All Undergraduate Projects

A great deal of composite waste is generated in the construction of wings for the Boeing 777. These carbon fiber “wing trimmings” are currently being disposed of in a landfill. These carbon fiber boards are made of several layers laminated together, making them very rigid and hard to recycle. This report proposes a method to delaminate the layers of these composite wing trimmings using a hydraulic press and a V-shaped steel die so that they may be more easily shredded and thus recycled. A top, “male” die with two points is pressed into a bottom, “female” die with three points …


Dual Graphene Patch Antenna For Ka Band Satellite Applications, Mohammed Amin Rabah, Mohammed Bekhti 2019 Satellite development center -Algerian Space Agency

Dual Graphene Patch Antenna For Ka Band Satellite Applications, Mohammed Amin Rabah, Mohammed Bekhti

International Journal of Aviation, Aeronautics, and Aerospace

Currently; grapheme offers a new opportunity to use in space technology and this is due to its amazing properties like conductivity, strength, flexibility and transparency which allows us to exploit new generation of ultra-fast nanoscale components; Since future wireless communication techniques are geared towards the use of the high frequency spectrum and many recent research prove this trend. This letter presents a proposal for design of a dual graphene-based antenna to use in new communication techniques in Ka band, where the proposed antenna can work for uplink and dowlink frequencies at same time since it has return loss less then …


Enhanced Surface Integrity With Thermally Stable Residual Stress Fields And Nanostructures In Cryogenic Processing Of Titanium Alloy Ti-6al-4v, James R. Caudill 2019 University of Kentucky

Enhanced Surface Integrity With Thermally Stable Residual Stress Fields And Nanostructures In Cryogenic Processing Of Titanium Alloy Ti-6al-4v, James R. Caudill

Theses and Dissertations--Mechanical Engineering

Burnishing is a chipless finishing process used to improve surface integrity by severe plastic deformation (SPD) of surface asperities. As surface integrity in large measure defines the functional performance and fatigue life of aerospace alloys, burnishing is thus a means of increasing the fatigue life of critical components, such as turbine and compressor blades in gas turbine engines. Therefore, the primary objective of this dissertation is to characterize the burnishing-induced surface integrity of Ti-6Al-4V alloy in terms of the implemented processing parameters. As the impact of cooling mechanisms on surface integrity from SPD processing is largely unexplored, a particular emphasis …


Bayesian Model Averaging Based Storage Lifetime Assessment Method For Rubber Sealing Rings, Di Liu, Shaoping Wang, Chao Zhang, Mileta M. Tomovic 2019 Old Dominion University

Bayesian Model Averaging Based Storage Lifetime Assessment Method For Rubber Sealing Rings, Di Liu, Shaoping Wang, Chao Zhang, Mileta M. Tomovic

Engineering Technology Faculty Publications

Rubber sealing ring is one of the most widely used seals. It is always stored for a period of time before put into use, especially in aeronautic and aerospace applications. It is necessary to evaluate the storage lifetime of rubber sealing rings. However, due to the long storage lifetime of rubber sealing rings, two issues need to be handled, including model uncertainty and lack of storage lifetime data. A Bayesian model averaging based storage lifetime assessment method for rubber sealing rings is proposed in this article. The Gamma distribution model and Weibull distribution model are selected as the candidate models …


Landing-Gear Impact Response: A Non-Linear Finite Element Approach, Tuan H. Tran 2019 University of North Florida

Landing-Gear Impact Response: A Non-Linear Finite Element Approach, Tuan H. Tran

UNF Graduate Theses and Dissertations

The primary objective of this research is to formulate a methodology of assessing the maximum impact loading condition that will incur onto an aircraft’s landing gear system via Finite Element Analysis (FEA) and appropriately determining its corresponding structural and impact responses to minimize potential design failures during hard landing (abnormal impact) and shock absorption testing. Both static and dynamic loading condition were closely analyzed, compared, and derived through the Federal Aviation Administration’s (FAA) airworthiness regulations and empirical testing data.

In this research, a nonlinear transient dynamic analysis is developed and established via NASTRAN advanced nonlinear finite element model (FEM) to …


Improving The Delivered Specific Impulse Of Composite Rocket Propellant Through Alteration Of Chemical Composition: Methodology And Parameters For Characterization Of Propellant And Validation Of Simulation Software Common To The Amateur Rocketry Community, Isaac O'Brien, Austin Ryan 2019 The University of Akron

Improving The Delivered Specific Impulse Of Composite Rocket Propellant Through Alteration Of Chemical Composition: Methodology And Parameters For Characterization Of Propellant And Validation Of Simulation Software Common To The Amateur Rocketry Community, Isaac O'Brien, Austin Ryan

Williams Honors College, Honors Research Projects

In this study, two solid composite rocket propellants were designed utilizing ProPEP, a rocket propellant formulation software common in the amateur and hobby rocketry communities. The two propellants were designed to optimize specific impulse relative to a literature propellant designed by 1020 Research Labs. The literature propellant was also tested in order to validate the design of experiment as well as the mixing and testing procedures. All three propellants, which includes the literature propellant RCS-P, and the two novel propellants AKR-P1 and AKR-P2 were characterized with static tests. The results of the static tests provide data on propellant performance and …


Prototype Landing Gear Conceptual And Embodiment Design, Derek Carr 2019 The University of Akron

Prototype Landing Gear Conceptual And Embodiment Design, Derek Carr

Williams Honors College, Honors Research Projects

Collin’s Aerospace Mechanical systems engineering was tasked with designing a set of landing gear for an undisclosed project. The landing gear is required to comply with customer specifications, coordinate systems, and overall landing gear performance. The purpose of this project is to document the conceptual and embodiment design process for an articulated main landing gear system. Unfortunately, due to high expenses and high lead times required for 300M stainless steel components, no full size prototype can be produced within the timeframe of this report. Instead, this document should be viewed as a process mapping guide for initial landing gear design …


Interlaminar Damage Detection In Composite Materials, Hariharan Rangarajan 2019 The University of Akron

Interlaminar Damage Detection In Composite Materials, Hariharan Rangarajan

Williams Honors College, Honors Research Projects

Using ceramic matrix composites (CMCs) for high-temperature applications in jet engines increases durability and reduces weight and cooling requirements resulting in improved efficiency and fuel savings. Understanding, detecting, and monitoring different types of damage is essential to achieve optimal performance of CMC components. The Direct Current Potential Drop (DCPD) method is a non-destructive technique of estimating damage in composite materials.

DCPD technique works by measuring nodal potential differences when current is flown through the material. Direct current spreading in different woven and laminate composites is modeled to follow a ladder resistor network in which the nodal voltages decrease exponentially as …


3d Textile Preforms And Composites For Aircraft Strcutures: A Review, Abbasali Saboktakin 2019 University of sistan and baluchestan, Zahedan, Iran

3d Textile Preforms And Composites For Aircraft Strcutures: A Review, Abbasali Saboktakin

International Journal of Aviation, Aeronautics, and Aerospace

Over the last decades, the development of 3D textile composites has been driven the structures developed to overcome disadvantages of 2D laminates such as the needs of reducing fabrication cost, increasing through-thickness mechanical properties, and improving impact damage tolerance. 3D woven, stitched, knitted and braided preforms have been used as composites reinforcement for these types of composites. In this paper, advantages and disadvantages of each of them have been comprehensively discussed. The fabric architects and their specification in particular stitched preforms and their deformation mode for aerospace applications have been reviewed. Exact insight into various types of damage in textile …


Fe Modeling Methodology For Load Analysis And Preliminary Sizing Of Aircraft Wing Structure, Jun Hwan Jang, Sang Ho Ahn 2019 Defense Acquisition Program Administration

Fe Modeling Methodology For Load Analysis And Preliminary Sizing Of Aircraft Wing Structure, Jun Hwan Jang, Sang Ho Ahn

International Journal of Aviation, Aeronautics, and Aerospace

It is a critical part at the basic design phase of aircraft structural design to build a finite element model and it will have a direct impact on time and cost for airframe structure development. In addition, the objective of finite element model will be varied depending on each design review phase and the modelling methodology varied accordingly. In order to build an effective and economic finite element model, it is required to develop adequate level of modelling methodology based on each design phase and its objectives. Therefore, in this paper, the finite element modeling methodology was presented for internal …


Investigation Of The Evolution Of Hydrophobicity And Wettability Of Paper In Multi-Color Printing Process, C Aydemir, A Karademir, S Imamoglu, Bilge N. Altay, Paul D. Fleming, D Tutak 2018 Marmara University

Investigation Of The Evolution Of Hydrophobicity And Wettability Of Paper In Multi-Color Printing Process, C Aydemir, A Karademir, S Imamoglu, Bilge N. Altay, Paul D. Fleming, D Tutak

Bilge Nazli Altay

One of the keys to improving print quality is to experimentally characterize the paper surface, structure and printability to obtain quality control mechanisms. In multi-color prints, determining the differences in the acceptance of the next color ink by the surface of the paper or the ink film that was previously printed is important for print quality. The criteria, such as ink setting, adhesion, color, gloss and density, in the printing process, depend on the wettability and absorbency of the paper. The surface structure of the paper is the most important factor in determining the hydrophobic properties. In this study, wetting …


Effect Of Aerogel On The Thermal Performance Of Corrugated Composite Sandwich Structures, Jacob Dillon Chess 2018 California Polytechnic State University, San Luis Obispo

Effect Of Aerogel On The Thermal Performance Of Corrugated Composite Sandwich Structures, Jacob Dillon Chess

Master's Theses

Current insulation solutions across multiple industries, especially the commercial sector, can be bulky and ineffective when considering their volume. Aerogels are excellent insulators, exhibiting low thermal conductivities and low densities with a porosity of around 95%. Such characteristics make aerogels effective in decreasing conductive heat transfer within a solid. These requirements are crucial for aerospace and spaceflight applications, where sensitive components exist among extreme temperature environments. When implemented into insulation applications, aerogel can perform better than existing technology while using less material, which limits the amount of volume allocated for insulation. The application of these materials into composites can result …


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