Engineering Commons^™

Editor's Note, Damon Coletta

Space and Defense

No abstract provided.

Table Of Contents, Space And Defense

Space and Defense

No abstract provided.

Front Matter Volume 8 No. 1, Space And Defense

Space and Defense

No abstract provided.

Comparative Evaluation Of Investigation Methods For Estimating The Load-Dependent State Of Charge And End Of Discharge Of A Multirotor Uav Battery, Hanna Dibbern, Morten Roßberg, Claudia Werner

Journal of Aviation Technology and Engineering

As the scope of multirotor unmanned aerial vehicle (UAV) applications increases, more attention is being paid to UAV energy requirements, which vary depending on the mission profile. To obtain accurate information about the UAV battery during flight, the idea of a digital twin including a battery state estimation model is promising. For battery state estimation, a Kalman filter combination is the preferred approach in the literature. Comparing different Kalman filters, the unscented Kalman filter has a more accurate estimation for nonlinear systems compared to the extended Kalman filter. In the application of UAV flight with load-dependent flight missions, the comparison …

Six-Degree-Of-Freedom Optimal Feedback Control Of Pinpoint Landing Using Deep Neural Networks, Omkar S. Mulekar, Hancheol Cho, Riccardo Bevilacqua

Student Works

Machine learning regression techniques have shown success at feedback control to perform near-optimal pinpoint landings for low fidelity formulations (e.g. 3 degree-of-freedom). Trajectories from these low-fidelity landing formulations have been used in imitation learning techniques to train deep neural network policies to replicate these optimal landings in closed loop. This study details the development of a near-optimal, neural network feedback controller for a 6 degree-of-freedom pinpoint landing system. To model disturbances, the problem is cast as either a multi-phase optimal control problem or a triple single-phase optimal control problem to generate examples of optimal control through the presence of disturbances. …

Notes For Contributors, Space And Defense

Space and Defense

No abstract provided.

Publisher’S Corner Space Policy’S Salt Moment, Roger G. Harrison

Space and Defense

The market for a leap forward in space arms control is open. Now, who’s buying? The United States is facing a fundamental decision about space policy which arises from a question: does our national interest in an ordered space environment trump our absolute insistence on a policy of freedom of action? Or is the looming threat of over-crowded orbits, frequency interference and debris – of contested, congested and competitive space – so pressing that we must accept some greater transparency for our national security space operations, even greater information sharing with China, Russia, and commercial space operators, and perhaps some …

Book Review Crowded Orbits: Conflict And Cooperation In Space By James Clay Moltz (Columbia University Press, 2014), Deron Jackson

Space and Defense

A popular space primer serves both the policy and academic communities. Human beings have perceived outer space as infinite for centuries, and since the observations of Edwin Hubble in the 1920s, scientists have studied phenomena that suggest the universe itself is expanding. However, as the title of Clay Moltz’s most recent book points out, the region of space most important to the economic and physical security of residents on Earth is increasingly viewed as far from infinite.

Meeting Growth Challenges Of Mexico Aerospace: The Queretaro Cluster, Monica Casalet

Space and Defense

Growing the Aerospace sector in Mexico requires multilevel agreement between original equipment manufacturers (OEMs), including foreign companies, and national and sub-national governments to stimulate programs and instruments for sector growth. In addition, space for local learning must be cultivated within a process of production organized hierarchically and highly regulated on the international level. The case of the Queretaro cluster is important due to the density of networks created, extensive public-private collaboration, and the emergence of specialized institutions to train and shape highly skilled (professionals and technicians) in the aerospace industry. Ultimately, there remains an important vacuum to fill in the …

Brazil Space: Military Dependency And The Case Of The Geostationary Satellite Of Defense And Strategic Communications, Gills Vilar Lopes

Space and Defense

In Brazil, there has been no transition model of space capabilities promoted by the military sphere (especially the Brazilian Air Force) for nurturing the civil one (Brazilian Space Agency). Drawing upon official documents and legislation as primary sources, the case study of the Geostationary Satellite of Defense and Strategic Communications (SGDC) is analyzed in light of the space strategic sector. Main factors that impede the PEB are related to military-technological dependence and poor resource management, with draconian budget cuts and projects canceled before having achieved realistic milestones.

Attack On The Brain: Neurowars And Neurowarfare, Armin Krishnan

Space and Defense

Is neurotechnology leading nation-states toward a new domain of war? Neuroscience is on the verge of deciphering the human brain. As a result, brains will become a part of the battlefield against which attacks will be directed. As neuroscientist James Giordano argued: “the brain is the next battlespace.” It is foreseeable that this will have tremendous implications for warfare and could amount to a true military revolution in the sense of military historian Williamson Murray: it would completely change the characteristics of conflict, as well as transform state and society.

Editor's Note Volume 9 No. 1, Damon Coletta

Space and Defense

No abstract provided.

Table Of Contents Volume 9 No. 1, Space And Defense

Space and Defense

No abstract provided.

Front Matter Volume 9 No. 1, Space And Defense

Space and Defense

No abstract provided.

Development, Implementation, And Evaluation Of Swirl-Combustion Strategies For Optimal Performance Of Ammonia As A Fuel For Gas Turbine Engines, Varun Nanjunda Rao Viswamithra

LSU Doctoral Dissertations

In an effort to reduce harmful effects of greenhouse gas emissions, ammonia is being pursued as a fuel for power generation as it is a carbon-free energy source. However, the use of ammonia-air mixtures in premixed swirl combustors poses challenges due to low flame speed and reactivity resulting in combustor stability issues in addition to high Nitrous Oxide (NOx) emissions due to the presence of fuel-bound Nitrogen. The first part of this study attempts to overcome lean blowout limits of methane-ammonia-air mixtures using a novel, multi-point () injection strategy, whereby micron-sized holes on the swirler vanes generate a co-flowing stream …

Development Of A Vortex-Cooled Bipropellant Thruster And Evaluation Of Performance Characteristics With Respect To Injection Parameters, Mousa Adnan Aqailan

Theses

This study presents an experimental assessment of the cooling performance and efficiency of a 10N-vortex-cooled Propane/Gox bi-propellant thruster that was fabricated using metal and thermoplastic material. The proposal of injecting an oxidizer in a vortex pattern was suggested as a potential cooling method for semi-thermoplastic constructed thrust engines. This method has been demonstrated as a promising candidate for integrated cooling and can be manufactured using 3D printing technology. In contrast to typical complicated cooling systems and their attributed common downsides; the vortex injection can be 3D printed as a single solid piece thruster, thereby reducing design complexity, weight, and manufacturing …

Electromagnetic Mems Safety And Arming Devices, Fatima Rashed Alnuaimi

Theses

This thesis aims to investigate the design of safety and arming devices within artillery fuzes, which rely on the spin velocity and setback acceleration of the weapon. These systems consist of two critical components: the spin lock and the inertia lock. The spin velocity and setback acceleration of the weapon induce deformations in these components, serving as key criteria for determining whether the weapon is in an armed or safe state.

The primary objective of this thesis is to comprehensively analyze and assess the design of both the spin lock and inertia lock. The research will delve into multiple factors …

Design And Fem Modelling Of Mems Capacitive Accelerometer And Gyroscope For Quadcopter/Uav Applications, Shaikha Rashid Alnaqbi

Theses

This study presents the design, simulation, and analysis of Micro Electromechanical Systems (MEMS) sensors, constituting the principal components of MEMS-based Inertial Measurement Units (IMUs). The main objective of the study is to design, simulate and analyze 3-axis capacitive accelerometer and 3-axis gyroscope. The MEMS-based capacitive accelerometers and gyroscope are analyzed using Ansys Workbench. Modal, Static Structural and harmonic analysis are used to obtain resonant frequencies, deformation/stress and profile of amplitude over a wide range of frequencies. Mechanical sensitivity analysis of the designed accelerometer and gyroscope is performed using the Finite Element Method (FEM). Analytical Equations are developed to calculate mechanical …

Implementation Of Experimental Static Recrystallization Of High Strength Steel Into Computational Simulation Of Multi-Pass Slab Hot Rolling, S. K. Dasari, S. Ganguly, A. Abutunis, K. Chandrashekhara, M. F. Buchely, S. N. Lekakh, R. J. O'Malley, T. Natarajan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Microstructural changes and softening due to static recrystallization have a critical influence on thermo-mechanical behavior of high strength steels during industrial multi-pass hot rolling. Numerical simulation using finite element analysis (FEA) can be used to accurately predict the softening behavior during the hot rolling process. Therefore, the implementation of an experimentally defined static recrystallization model into FEA is necessary to get realistic simulation prediction. in this study, the extent of softening during static recrystallization in Si and Mn alloyed high strength steel was measured using double hit tests. a Gleeble™ thermo-mechanical simulator was used to perform the double hit tests …

Design Of Impact-Free Gaits For Planar Bipeds And Their Stabilization Using Impulsive Control, Aakash Khandelwal, Nilay Kant, Ranjan Mukherjee

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The problem of designing and stabilizing impact-free gaits is considered for point-foot planar bipeds. A set of geometric constraints, which eliminate impact forces at the time of leg interchange, are used to design the gaits. A family of gaits, where the stride length and walking speed can be chosen independently for each gait, is guaranteed to exist. A continuous controller is used to enforce the constraints associated with a desired gait and intermittent impulsive inputs are applied to stabilize the gait. A five-link biped example is used to illustrate the procedure for designing impact-free gaits. The effectiveness of the continuous …

Flying To Net Zero With Sustainable Atos; Changing Cultures​, Eva Maleviti

Publications

What is Sustainability?

• World Commission on Environment and Development’s (WCED) 1987 Brundtland Report ‘’Our Common Future’’.
• Help world nations towards sustainable development.

17 Sustainable Development Goals

• The start of all industries are the 17 SDGs
• Aviation can address the 15 SDGs
• Net zero target suggest reduction of aviation emissions up to 21.2 Gt CO2

Searching For Unknown Material Properties For Am Simulations, Aaron Flood, Rachel Boillat, Sriram Praneeth Isanaka, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Additive manufacturing (AM) simulations are effective for materials that are well characterized and published; however, for newer or proprietary materials, they cannot provide accurate results due to the lack of knowledge of the material properties. This work demonstrates the process of the application of mathematical search algorithms to develop an optimized material dataset which results in accurate simulations for the laser directed energy deposition (DED) process. This was performed by first using a well-characterized material, Ti-64, to show the error in the predicted melt pool was accurate, and the error was found to be less than two resolution steps. Then, …

Towards A Virtual Test Framework To Predict Residual Compressive Strength After Lightning Strikes, Scott L.J. Millen, Xiaodong Xu, Juhyeong Lee, Suparno Mukhopadhyay, Michael R. Wisnom, Adrian Murphy

Mechanical and Aerospace Engineering Faculty Publications

A novel integrated modelling framework is proposed as a set of coupled virtual tests to predict the residual compressive strength of carbon/epoxy composites after a lightning strike. Sequentially-coupled thermal-electric and thermo-mechanical models were combined with Compression After Lightning Strike (CAL) analyses, considering both thermal and mechanical lightning strike damage. The predicted lightning damage was validated using experimental images and X-ray Computed Tomography. Delamination and ply degradation information were mapped to a compression model, with a maximum stress criterion, using python scripts. Experimental data, in which artificial lightning strike and compression testing were performed, was used to assess the predictive capabilities …

On Quantifying Uncertainty In Lightning Strike Damage Of Composite Laminates: A Hybrid Stochastic Framework Of Coupled Transient Thermal-Electrical Simulations, R. S. Chahar, J. Lee, T. Mukhopadhyay

Mechanical and Aerospace Engineering Faculty Publications

Lightning strike damage can severely affect the thermo-mechanical performance of composite laminates. It is essential to quantify the effect of lightning strikes considering the inevitable influence of material and geometric uncertainties for ensuring the operational safety of aircraft. This paper presents an efficient support vector machine (SVM)-based surrogate approach coupled with computationally intensive transient thermal-electrical finite element simulations to quantify the uncertainty in lightning strike damage. The uncertainty in epoxy matrix thermal damage and electrical responses of unprotected carbon/epoxy composite laminates is probabilistically quantified considering the stochasticity in temperature-dependent multi-physical material properties and ply orientations. Further, the SVM models are …

Aerodynamic & Aeroacoustic Performance Of Wind Turbine Blades Featuring Enhanced Flow-Control, Md Zishan Akhter

Dissertations

Wind energy, being one of the cleanest and most sustainable sources, has undergone remarkable growth in recent years due to advancements in aerodynamics and increased power output. The research community is actively pursuing the development of cutting-edge solutions to further optimize wind turbine technology, ensuring its maximum efficiency and revolutionizing the landscape of wind power.
/="/">This research aims to design and develop flow-control devices for wind turbine blades, employing both active and passive control mechanisms, namely morphing trailing-edge and slot-profile, respectively. The objective is to enhance wind turbine performance across a wide range of wind speeds. The morphing trailing-edge …

Exploring Underwater Noise Issues : A Study Of Decentralized Approach, Takanori Uzumaki

World Maritime University Dissertations

No abstract provided.

Notes For Contributors, Space And Defense

Space and Defense

No abstract provided.

Cadet Voice: A Curious Trinity: War, Media, And Public Opinion, Laura Olson

Space and Defense

The following USAFA cadet Capstone project from spring 2017 won the Best Undergraduate Class Paper Award from the national Political Science honor society, Pi Sigma Alpha. The article appears, below, as submitted, with allowances for Space & Defense formatting.

August, 2012- President Obama drew a “Red Line” on chemical weapons use in Syria. Just over a year later, a UN report confirmed Syrian chemical use. Two words, spoken by the most powerful man in the world, generated massive media coverage. Around the world, news outlets and people everywhere looked for Washington’s reaction. Words are powerful because of the narrative they …

Arms Control And Deterrence In The Age Of Cross-Domain Coercion, Damon Coletta

Space and Defense

For deterrence, now, first seek arms control. The old relationship linking deterrence, defense, and arms control served U.S. policy makers for decades during the Cold War. It was manifest through the Spirit of Geneva (1955) and the Reykjavik Summit (1986). Much later, during the rise of cross-domain coercion and following Russia’s annexation of Crimea, the same idea reemerged in NATO’s Warsaw Communique (2016).

Building Beyond Samba And Soccer: Why Brazil Ventured A Nuclear Program, Saint-Clair Lima Da Silva

Space and Defense

Contrary to conventional wisdom on Brazil as a case of nuclear proliferation, archival evidence indicates that, rather than geopolitical rivalry with Argentina, enduring desire for national autonomy—honor more than sword or shield—drove Brazil during the 1980s to master its own uranium enrichment cycle.