Aerospace Engineering Commons^™

Pareto Ranking Bisection Algorithm For Em-Driven Multi-Objective Design Of Antennas In Highly-Dimensional Parameter Spaces, Adrian Bekasiewicz, Slawomir Koziel, Leifur Leifsson, Xiaosong Du

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A deterministic technique for fast surrogate-assisted multi-objective design optimization of antennas in highly-dimensional parameters spaces has been discussed. In this two-stage approach, the initial approximation of the Pareto set representing the best compromise between conflicting objectives is obtained using a bisection algorithm which finds new Pareto-optimal designs by dividing the line segments interconnecting previously found optimal points, and executing poll-type search that involves Pareto ranking. The initial Pareto front is generated at the level of the coarsely-discretized EM model of the antenna. In the second stage of the algorithm, the high-fidelity Pareto designs are obtained through optimization of corrected local-approximation …

Assessment Of Multimode Spacecraft Micropropulsion Systems, Steven P. Berg, Joshua L. Rovey

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Multimode spacecraft micro propulsion systems that include a high-Thrust chemical mode and high-specific impulse electric mode are assessed with specific reference to CubeSat-sized satellite applications. Both cold-gas butane propellant and ionic liquid chemical monopropellant modes are investigated alongside pulsed plasma, electrospray, and ion electric thruster modes. These systems are studied by varying electric propulsion usage percent and calculating the payload mass fraction and thruster burn time for missions requiring 250, 500, and 1000 m/s delta-V. Systems involving chemical monopropellants have the highest payload mass fractions for a reference mission of 500 m/s delta-V and 6U-sized CubeSat, where 1U is a …

Resilient Control Of Active-Passive Networked Multiagent Systems In The Presence Of Persistent Disturbances, Dzung Tran, Tansel Yucelen, John Daniel Peterson

Mechanical and Aerospace Engineering Faculty Research & Creative Works

An active-passive networked multiagent system consists of agents subject to inputs (active agents) and agents without any inputs (passive agents). Specifically, this class of networked multiagent systems utilizes a novel form of dynamic consensus filters, where the states of all agents converge to the average of the exogenous inputs applied only to the active agents, and it has broad practical applications including, for example, real-time situational awareness and data gathering using sensor networks and distributed control of multirobot systems. In this paper, we focus on active-passive networked multiagent systems that are subject to constant and/or harmonic exogenous disturbances. In particular, …

Fifty-Plus-Year Postflight Analysis Of First Fluid Experiment Aboard A Spacecraft, Mark M. Weislogel, Yongkang Chen, William J. Masica, Fred J. Kohl, Robert D. Green

Mechanical and Materials Engineering Faculty Publications and Presentations

This year marks the 55th anniversary of the first fluid physics experiment performed aboard a spacecraft during the Mercury-Atlas 7 mission. Since then, NASA has conducted over 80 fluids physics experiments aboard a variety of spacecraft, many of which have enhanced the understanding of large-length-scale capillary phenomena relevant to liquid management in the weightless state. As both celebration and demonstration, the Mercury-Atlas 7 fluids experiment is revisited in light of the current understanding of large-length-scale capillary fluidics. Employing a modern numerical tool, a rich variety of experimental outcomes are discovered that were not observed during the flight experiment. Interestingly, experimental …

Experimental Investigation Of Cryogenic Convection And Boiling In Traditionally And Additively Manufactured Rocket Engine Cooling Channels, Armando Sandoval

Open Access Theses & Dissertations

The Center for Space Exploration and Technology Research at the University of Texas at El Paso, has designed, built, and optimized an experimental high heat flux test facility to investigate the heat transfer coefficient of liquid methane and other cryogenic propellants for regenerative cooled rocket engine design. The system is composed of a copper conduction based thermal concentrator that delivers heat flow into a single sub-scaled cooling channel (test article). This study focuses on optimizing this design of the high heat flux test facility to develop a more accurate method for measuring the conductive heat flow going into the cooling …

Quantifying The Characteristic Length Of A Combustor For An Ionic Liquid Monopropellant Thruster, Kimberly Marie Hogge

Open Access Theses & Dissertations

Ionic liquid monopropellants are currently being researched as a promising alternative to hydrazine in propulsion systems. This report presents a flame study that delineates the flame length of the expected decomposition products from an ionic liquid monopropellant. Through these studies, the characteristic length of a combustion chamber will be defined through calculations and empirical correlations. There is limited information on designing a propulsion system for an ionic liquid monopropellant. Therefore, defining the magnitude for an effective characteristic length serves as beneficial in designing a propulsion system for an ionic liquid monopropellant thruster.

Performance Degradation Analysis Of Aviation Hydraulic Piston Pump Based On Mixed Wear Theory, C. Zhang, S. Wang, M. Tomovic, L. Han

Engineering Technology Faculty Publications

This paper focuses on the mathematical modeling of axial piston pump through dividing the failure development of friction pair into lubrication, mixed lubrication and abrasion. Directing to the wedge-shaped oil film between cylinder block and valve plate, the support force distribution under the temperature variance was obtained. Considering the rough peak of valve plate, the contact load model is built under plastic deformation and elastic deformation and the corresponding wear volume is calculated. Computing the wear and tear along the counter-clockwise, the total amount of friction and wear can be calculated. Simulation and preliminary wear particle monitoring test indicates that …

Variable Structure Feedback Control With Application To Spacecraft With Small Thrust Propulsion Systems, Samuel J. Kitchen-Mckinley

Doctoral Dissertations and Master's Theses

Small spacecrafts requiring small propulsion systems are becoming more popular for low Earth orbit. It is important for these research satellites to have accurate guidance and control systems. Small propulsion systems will also be beneficial for multiple small spacecrafts used future exploration expeditions beyond low Earth orbit. These small spacecrafts benefit from the simplicity of low thrust cold gas propulsion systems. Additionally, large spacecrafts using low thrust, high specific impulse propellants for main propulsion systems, such as ion engines, allow longer and more flexible missions, including Earth orbiting spacecraft and interplanetary spacecraft.

In order to extend the life of future …

Shear Driven Micro-Fluidic Pump, Nihad E. Daidzic

Aviation Department Publications

United States Patent, Patent Number US 9,528,503 B2, Date of Patent December 27, 2016.

An example includes an apparatus to pump a fluid. The apparatus includes a housing extending along a length defining an elongate interior, an actuator in the housing, conforming to the elongate interior, the actuator including a plurality of lumens, each having a length extending substantially parallel to the elongate interior, each from around 10 to 200 micrometers across and an actuator configured to oscillate the actuator in the actuator houslng along the length of the elongate interior with a rate differential between movement in a first …

Spacex: Breaking The Barrier To The Space Launch Vehicle Industry, Matthew M. Liskowcyz

Theses and Dissertations

The Space Launch Vehicle (SLV) industry has been around for a long time, but few companies have managed to enter this industry. SpaceX was founded only 10 years ago, but it has managed to become a leader in the U.S. industry and a dominant player worldwide. The purpose of this thesis research is to discover what it took for SpaceX to break into this tightly controlled industry. A qualitative analysis was performed to compare SpaceX to companies that overcame the barriers of entry for their respective industries. SpaceX, like FedEx, could implement a unique technique to the industry and find …

Phased Helical Antenna Array For Cubesat Application, Kameron Lacalli

Undergraduate Honors Theses

CubeSats communication links are typically slow due to their power and size restrictions. However, a low power, high speed down link connection can allow for greater data collection and relaying, pushing the capability of 1U CubeSats beyond what is traditionally thought possible. Investigated here is the feasibility of a 11 Mb/s down link connection on a 1U CubeSat, accomplished via 2x2 helical antenna phased array operating on the 802.11 standard. Using a phased array also allows for beam steering to secure connection with the ground station when the on board ADCS may not provide precise pointing capability of the CubeSat, …

Design Of A Modified Stewart Platform Manipulator For Misalignment Correction, Adekunle Ayoko

Master of Technology Management Plan II Graduate Projects

This thesis work is about the design of a modified Stewart platform manipulator for misalignment correction. The common version of the Stewart platform uses six actuators. The traditional Stewart platform of this kind has a moving top plate and a fixed base plate. However, in this research, the modified design of the traditional Stewart platform is studied. It is designed to be an easy connect-disconnect platform that can wrap around different structures with different cross sections and symmetrically designed. It is able to adjust position easily by using four identical but independent linear actuators populated evenly in two parts fastened …

Geostationary Operational Environmental Satellite- R Series (Goes-R) 2016, Paige N. Dixon

Student Works

This is a report on the first NOAA GOES-R satellite, launched on November 19th, 2016. This report will cover some of the details of the GOES-R project, as well as discuss the collaborations that made the project possible. This document will also detail some of the new satellite’s capabilities including geostationary lightning detection, and space weather monitoring, and will focus on real-world application of such technology. Additionally, this report will list some of the current and projected GOES-R products, and the potential benefits if testing proves successful.

A Multi-Agent System For Adaptive Control Of A Flapping-Wing Micro Air Vehicle, Michal Podhradský

Dissertations and Theses

Biomimetic flapping-wing vehicles have attracted recent interest because of their numerous potential military and civilian applications. In this dissertation is described the design of a multi-agent adaptive controller for such a vehicle. This controller is responsible for estimating the vehicle pose (position and orientation) and then generating four parameters needed for split-cycle control of wing movements to correct pose errors. These parameters are produced via a subsumption architecture rule base. The control strategy is fault tolerant. Using an online learning process, an agent continuously monitors the vehicle's behavior and initiates diagnostics if the behavior has degraded. This agent can then …

Local Field Effects On Magnetic Suppression Of The Converging Richtmyer-Meshkov Instability, Vincent Wheatley, Wouter Mostert, D. M. Bond, Ravi Samtaney

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We examine how the suppression of the converging shockdriven Richtmyer-Meshkov instability by an applied magnetic field is dependent on the local magnetic field strength and orientation. In particular, we examine whether the extent of suppression can be reasonably predicted by a linear model for the planar case. This is done for cylindrically converging cases with a high perturbation wavenumber and two different initial magnetic field configurations.

Attitude Determination Control Testing System (Helmholtz Cage And Air Bearing), Nicolas Theoret

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.

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.

Interplanetary Mission Design With Applications To Guidance And Optimal Control Of Aero-Assisted Trajectories, Peter J. Edelman

Open Access Dissertations

A method for finding optimal aerogravity-assist tours of the solar system is developed using indirect methods. Two cost functionals are used in the optimization; finding the minimum required maximum lift-to-drag ratio, with and without a convective heating-rate path constraint, and the path which provides the minimum total stagnation point convective heat load. It is found that using present or near-future thermal protection system materials will suffice for certain aerogravity assist trajectories at Mars. Minimum heat load optimal trajectories are found for aerocapture maneuvers at Uranus and Neptune. With a large radius, and short rotational periods, atmospheric rotation must be taken …

Secondary Instabilities Of Hypersonic Stationary Crossflow Waves, Joshua Benjamin Edelman

Open Access Theses

A sharp, circular 7° half-angle cone was tested in the Boeing/AFOSR Mach-6 Quiet Tunnel at 6° angle of attack. Using a variety of roughness configurations, measurements were made using temperature-sensitive paint (TSP) and fast pressure sensors. High-frequency secondary instabilities of the stationary crossflow waves were detected near the aft end of the cone, from 110° to 163° from the windward ray.

At least two frequency bands of the secondary instabilities were measured. The secondary instabilities have high coherence between upstream and downstream sensor pairs. In addition, the amplitudes of the instabilities increase with the addition of roughness elements near the …

Towards Artificial Proprioception In The Mandibular Full Arch Fixed Implant Prosthesis, Md Abu Hasan

Mechanical and Aerospace Engineering Dissertations - Archive

Full arch fixed implant prosthesis has been one of the most effective treatment modalities for fully edentulous patients over the last few decades. However, due to lack of proprioception occlusal overload is experienced by the prosthesis and its components causing major biomechanical complications such as screw/abutment fracture, framework fracture, and bone loss. The currently available approaches for the overload management rely on external appliances such as an occlusal splint or bite guard and result in occlusal discomfort and high patient dissatisfaction. In this research, an approach to induce artificial proprioception in the full arch fixed implant prosthesis is proposed. However, …

A Framework For Employing Femtosatellites In Planetary Science Missions, Including A Proposed Mission Concept For Titan, Tracie Renea Conn Perez

Mechanical and Aerospace Engineering Dissertations - Archive

Over the past 15 years, there has been a growing interest in femtosatellites, a class of tiny satellites having mass less than 100 grams. Research groups from Peru, Spain, England, Canada, and the United States have proposed femtosat designs and novel mission concepts for them. In fact, Peru made history in 2013 by releasing the first – and still only – femtosat tracked from LEO. However, femtosatellite applications in interplanetary missions have yet to be explored in detail. An interesting operations concept would be for a space probe to release numerous femtosatellites into orbit around a planetary object of interest, …

Pilot Demonstration Based Reinforcement Learning With Application To Low Speed Airship Control, Onur Daskiran

Mechanical and Aerospace Engineering Dissertations - Archive

Designing control systems for airship has unique challenges as compared to conventional aircraft. Highly nonlinear dynamics, different mass/inertia relations, vast uncertainties in the model parameters and underactuation are the main reasons behind this. Airship dynamics is greatly influenced by the variations in the environmental (e.g.,room temperature) and internal (e.g., helium distribution in envelope) factors that can completely change the response characteristics of the blimp and make it infeasible for a model-based controller to perform. On the other hand, a skilled RC pilot can operate the manual flight easily under these conditions. This makes LfD (learning from demonstration) and RL (reinforcement …

A Stochastic Distributed Control Allocation Method Using Probability Collectives, Christopher Michael Elliot

Mechanical and Aerospace Engineering Dissertations - Archive

The configuration of the aerospace vehicle of tomorrow marches forward in complexity in step with technological advances in computation, materials, propulsion, and beyond. One of many attributes resulting from this evolution is the multiple effector concept, replacing the traditional aircraft design approach of a dedicated four channel mixer where pitch-roll-yaw-speed is controlled by elevator-aileron-rudder-engine, respectively. Instead, for example on the propulsion front, a distributed suite of smaller engines can substitute the larger power plant and can be used in concert for multiple axis control with both simultaneous, collective thrust for force generation and differential cyclic thrust for moment generation. The …

System Health Monitoring Using Multiple-Model Adaptive Estimation Techniques, Stanley Ryan Sifford

Mechanical and Aerospace Engineering Dissertations - Archive

Monitoring system health for fault detection and diagnosis by tracking system parameters concurrently with state estimates is approached using a new multiple-model adaptive estimation (MMAE) method. This novel method is called GRid-based Adaptive Parameter Estimation (GRAPE). GRAPE expands existing MMAE methods by using new techniques to sample the parameter space. GRAPE expands on MMAE with the hypothesis that sample models can be applied and resampled without relying on a predefined set of models. GRAPE is initially implemented in a linear framework using Kalman filter models. A more generalized GRAPE formulation is presented using extended Kalman filter (EKF) models to represent …

Numerical Modeling Of Capillary Driven Microfluidic Flow, Md Ashraful Islam

Mechanical and Aerospace Engineering Dissertations - Archive

Capillary driven two dimensional axisymmetric and three dimensional asymmetric flow in various microfluidic applications have been modeled and analyzed numerically. The transient Navier-Stokes equations are solved using a finite-difference formulation with a two-step projection method on a fixed grid. The vapor-liquid interface of the micro-droplet is tracked by volume-of-fluid (VOF) and coupled level set and volume-of-fluid (CLSVOF) methods with the surface tension force determined by the continuum surface force (CSF) model. The static contact angle at the three phase contact line has been modeled using wall adhesion scheme within the CSF framework. The developed numerical method for capturing the microfluidic …

Optimization Of Water And Energy Use In Indirect Evaporative Cooling System By Cfd, Mansi Vijay Prajapati

Mechanical and Aerospace Engineering Theses - Archive

Data center cooling is becoming important to maintain environmental condition for ITE- Information technology equipment. Conventional evaporative wet cooling media lowers the temperature of the dry bulb temperature of incoming air in which heat transfer to water film and sensibly cool the product air by increasing moisture into air. Wet cooling media technique requires large quantity of clean water, which is reducing area where water is very less. Therefore, indirect evaporative cooling is good alternative. Chiller plants/Indirect Evaporative cooling(IEC) are used as a cooling source for larger data centers as they are more efficient in heat transfer without adding moisture …

Self-Propulsion Of Liquid Drops Between Non-Parallel Structures At Leidenfrost State, Manjarik Mrinal

Mechanical and Aerospace Engineering Theses - Archive

In this work, we explored self-propulsion of a liquid drop between non-parallel structures at a temperature above its Leidenfrost point. A theoretical model was first developed to determine conditions for a drop to move away from the corner of two non-parallel plates. Subsequently, these results were validated by experiments. Finally, in Leidenfrost states, both lyophilic and lyophobic drops were shown to have the same dimensional movements away from the corner of two non-parallel plates.

Effect Of Pcb Thickness On Solder Joint Reliability Of Qfn Package Under Power And Thermal Cycling, Srinivas Rahul Rao

Mechanical and Aerospace Engineering Theses - Archive

Failure analysis and its effects are major reliability concerns in electronic packaging. More accurate fatigue life prediction can be obtained after the consideration of all affecting loads on the electronic devices. When an electronic device is turned off and then turned on multiple times, it creates a loading condition called power cycling. The die is the only heat source causing non-uniform temperature distribution. The solder joint reliability assessment of Quad Flat no-lead Package (QFN) is done through computational method i.e. Finite element analysis (FEA) under two different loads. In this paper, the power cycling and thermal cycling act as a …

Finite Element Modeling And Stress Distribution Of Unidirectional Composite Materials Under Transversal Loading, Pavan Agarwal

Mechanical and Aerospace Engineering Theses - Archive

Micromechanics of Composites analyze stresses inside any heterogeneous material. These stresses can not only be used for calculation of effective stiffness or compliance, but also for predicting strength and failure modes for these materials. This thesis is devoted to the stress analysis of unidirectional composites by finite element method. The key distinction from other finite element method modeling of the unidirectional composite was that the load on the cell was not prescribed, but was to be calculated taking into account the influence of the closest neighbors of the cell. Transversal unidirectional tension/compression and transversally symmetrical biaxial tension/compression were analyzed. In …

Non-Invasive Measurement Of The Internal Temperature Of Heat-Generating Bodies, Dean Raymond Anthony

Mechanical and Aerospace Engineering Theses - Archive

While the surface temperature of a heat-generating solid body can be measured using a variety of methods, there is a scarcity of techniques that exist for non-invasively measuring the temperature inside the solid body. Internal temperature measurement is very desirable as mere measurement of surface temperature gives no indication of the internal temperature. The highest temperature, usually located at the core of the body, dictates system performance and safety. For example, Li-ion cells provide good energy storage and conversion characteristics, but unfortunately suffer from safety problems related to overheating due to insufficient heat removal during operation. The following thesis presents …