Aerospace Engineering Commons^™

Intelligent Sensing Based On Low Cost Unmanned Aerial Vehicles (Uav) For Bridge Condition Assessment, Theodore Teates, Austin Boyd, Chung-Hao Chen

Electrical & Computer Engineering Faculty Publications

The eventual completion of this project envisions the use of an Unmanned Aerial Vehicle (UAV) to inspect bridge infrastructure. This project may also be expanded to encompass general object detection and inspection in order to unburden this technology so that it may reach its fullest potential. The project requires research and development in three distinct areas of image processing, control structures, and integration of systems. Initial undergraduate research sets the base knowledge for the overall project, explores the areas of concentration that are desired to expand upon in the future project, and provides a base UAV model that new researchers …

Adaptive Control Of Uncertain Systems With Gain Scheduled Reference Models And Constrained Control Inputs, Mehrdad Pakmehr, Tansel Yucelen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper develops a new state feedback model reference adaptive control approach for uncertain systems with gain scheduled reference models in a multi-input multi-output (MIMO) setting with constrained control inputs. A single Lyapunov matrix is computed for multiple linearization of the nonlinear closed loop gain scheduled reference system, using convex optimization tools. This approach guarantees stability of the closed loop gain scheduled reference model. Adaptive state feedback control architecture is then developed, and its stability is proven for the case with constrained control inputs. The resulting closed-loop system is shown to have bounded solutions with bounded tracking error, with the …

Thermal-Electromagnetic Analysis Of Infrared Antennas, Edward C. Kinzel, Brian Slovick, James Ginn, Brian Lail, Glenn Boreman

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Antenna-coupled Metal-Oxide-Metal (MOM) diodes have been demonstrated for sensing and proposed for energy harvesting at THz, infrared, and even visible frequencies. The design of the antenna allows engineering of the response of the device with respect to polarization, wavelength and angle of incidence. The classic understanding of the antenna coupled MOM diode is that the electric field generated by the antenna causes electrons to tunnel through the barrier oxide. This is supported by the fact that when the oxide separates metals with different work functions, a properly polarized field can produce an asymmetric tunnel current under zero bias. Losses in …

Verifiable Frequency-Limited Adaptive Control Performance Based On Linear Matrix Inequalities, Mario Luca Fravolini, Tansel Yucelen, Daniel Wagner, Ali Albattat, Paolo Valigi

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Adaptive controllers are often criticized for the lack of clear and easy verification procedures that relate design parameters to time domain performance especially during transients. For this reason, it is a challenge to rigorously certify existing adaptive control algorithms. To that end, we propose a validation framework where stability and performance requirements are formulated in terms of Linear Matrix Inequalities. This brings the advantage that adaptive controller design and verification can be analyzed and optimized via the solution of a convex optimization whose objective is to guarantee the evolution of the error components within an a-priori specified domain. This approach …

The Effect Of Different Rollover Conditions Of The Vibrator On Human Injury, Qin Li, Hang Liu, Zhiqiang Huang, Yaping Ding, Xiaoping Du

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Vibrator, as a crucial vehicle of oil and gas exploration, is challenged by the complex terrains. The probability of rollover accident is therefore high in bumpy terrain in which the drivers' life is seriously threatened. Finite element numerical analysis was used to study the injury of the driver's head, neck and chest in the rollover accidents of domestic KZ-28 type vibrator on different conditions. The injuries of three parts were evaluated based on the human injury criteria. Driver's safety on different rollover conditions was comparatively analyzed. The results indicated that the injury degree of human head caused by vibrator rollover …

Decomposition Of Ionic Liquid Ferrofluids For Multi-Mode Spacecraft Propulsion, Steven P. Berg, Brynne Coleman, Joshua L. Rovey

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Ionic liquid ferrofluids based on mixtures of [Emim][EtSO4] and [Bmim][NO3] fuels and hydroxylammonium nitrate oxidizer were synthesized by adding iron oxide nanoparticles. The resulting propellants were then tested for decomposition capability. Spot plate testing indicated that the temperature required to initiate rapid decomposition dropped from 115 °C to 75 °C with a 30% by weight addition of iron oxide for the [Bmim][NO3] propellant. Adding more iron oxide resulted in an increase in onset temperature. The [Emim][EtSO4] propellant had a much lower decrease in onset temperature, bottoming out at 90 °C. Batch reactor tests under vacuum showed that 10% addition of …

Importance Of Sources Using The Repeated Fusion Method And The Proportional Conflict Redistribution Rules #5 And #6, Florentin Smarandache, Jean Dezert

Branch Mathematics and Statistics Faculty and Staff Publications

We present in this paper some examples of how to compute by hand the PCR5 fusion rule for three sources, so the reader will better understand its mechanism. We also take into consideration the importance of sources, which is different from the classical discounting of sources.

Role Of Surface Chemistry In Nanoscale Electrokinetic Transport, Secuk Atalay

Mechanical & Aerospace Engineering Theses & Dissertations

This dissertation work presents the efforts to study the electrofluidics phenomena, with a focus on surface charge properties in nanoscale systems with the potential applications in imaging, energy conversion, ultrafiltration, DNA analysis/sequencing, DNA and protein transport, drug delivery, biological/chemical agent detection and micro/nano chip sensors.

Since the ion or molecular or particle transport and also liquid confinement in nano-structures are strongly dominated by the surface charge properties, in regards of the fundamental understanding of electrofluidics at nanoscale, we have used surface charge chemistry properties based on 2-pK charging mechanism. Using this mechanism, we theoretically and analytically showed the surface charge …

Analysis And Implementation Of Pm Sampling Methodology Protocols To Aid In The Development Of An Arp (Aerospace Recommended Practice) For Aircraft Non-Volatile Pm Measurements, Brian Lowell Catron

Masters Theses

"Due to the growing concerns that particulate matter (PM) have on health and the environment, there is a need to include mass and number non-volatile PM measurements to current jet engine certification. This thesis looks at the necessary work required to help produce recommendations and perform background research to aid in the creation of an improved Aerospace Recommended Practice (ARP) (by the SAE E-31 Committee). This work addressed the following issues. The investigation began in the Missouri S&T Center of Excellence for Aerospace Particulate Emissions Reduction Research (COE) laboratory with an examination of the jet engine surrogate used, the miniCAST, …

Characterizing Cryogenic Propellant Flow Behavior Through A Cavitating Venturi In Comparison To Alternative Flow Control Mechanisms, Marjorie Adele Ingle

Open Access Theses & Dissertations

The work detailed is an investigation of the use of a cavitating venturi as both a flow control and metering device. This was achieved through the combination of actual experimentation and numerical modeling of the fluid behavior of both liquid water and liquid methane as it passes through the test article designed, developed, and validated here within this study. The discharge coefficient of the cavitating venturi was determined through weigh flow calibration testing to determine an average mass flow rate. Turbine flow meter flow rate readings were used as a point of comparison and the discharge coefficient was computed. The …

Identifiability Of Additive Actuator And Sensor Faults By State Augmentation, Suresh M. Joshi, Oscar R. Gonzalez, Jason M. Upchurch

Electrical & Computer Engineering Faculty Publications

A class of FDI (fault detection and identification) methods for bias-type actuator and sensor faults was explored from the point of view of fault identifiability. The methods use banks of Kalman-Bucy filters (KBFs) to detect faults, determine the fault pattern, and estimate the fault values. A complete characterization of conditions for identifiability of bias-type actuator faults, sensor faults, and simultaneous actuator and sensor faults was presented. It was shown that FDI of simultaneous actuator and sensor faults is not possible using these methods when all sensors have unknown biases. The fault identifiability conditions were demonstrated via numerical examples. The analytical …

A Wedge Impact Theory Used To Predict Bow Slamming Forces, Ashok Benjamin Basil Attumaly

LSU New Orleans Theses and Dissertations

The pressures and impact forces acting on a hull while experiencing bow wave slamming is analyzed using Vorus' Impact Theory. The theory extends the hydrodynamic analysis of planing hulls from simple wedges to irregular shapes using a Boundary Element Method. A Fortran-based code developed by the Author is used to analyze hullforms. Linear strip theory is used to extend the analysis over a three dimensional hull. Post-processing of output data gives hull pressure distributions at different time steps and is visually presentable.

Impact pressure, Impact force, Planing, Wave slamming, Bow impact, Vorus' theory, Boundary Element Method, Linear strip theory

Experimental Investigation Of Mist Film Cooling And Feasibility Study Of Mist Transport In Gas Turbines, Reda M. Ragab

LSU New Orleans Theses and Dissertations

In the modern advanced gas turbines, the turbine inlet temperature may exceed 1500°C as a requirement to increase power output and thermal efficiency. Therefore, it is imperative that the blades and vanes are cooled so they can withstand these extreme temperatures. Film cooling is a cooling technique widely used in high-performance gas turbines. However, the film cooling effectiveness has almost reached plateau, resulting in a bottleneck for continuous improvement of gas turbines' efficiency.

In this study, an innovative cooling scheme, mist film cooling is investigated through experiments. A small amount of tiny water droplets with an average diameter about 10-15 …

Buckling, Postbuckling And Imperfection Sensitivity Analysis Of Different Type Of Cylindrical Shells By Hui's Postbuckling Method, Hailan Xu

LSU New Orleans Theses and Dissertations

Hui and Chen (1986) were the first to show that the well-known Koiter’s General Theory of Elastic Stability of 1945 can be significantly improved by evaluating the postbuckling b coefficient at the actual applied load, rather than at the classical buckling load. Such improvement method was demonstrated to be (1) very simple to apply with no tedious algebra, (2) significant reduction in imperfection sensitivity and (3) although it is still asymptotically valid, there exists a significant extension of the range of validity involving larger imperfection amplitudes. Strictly speaking, Koiter’s theory of 1945 is valid only for vanishingly small imperfection amplitudes. …

Investigation Into The Mitigation Of The Effects Of Uncertain Optical Degradation On An Interplanetary Solar Sail Mission Using A Single Model Update, Jordan Smiroldo

Master's Theses

The renewed academic interest in using solar sails as a source of spacecraft propulsion has been accompanied by a recent fervor of investigations into non-ideal and off-nominal sail performance considerations. One of the most influential considerations, uncertain optical degradation, has been shown to present significant trajectory design difficulties. This paper investigates the potential of using a mid-course degradation model update to mitigate the risk of missing the target destination in a sample 300 day Earth-Venus trajectory. Using a range of potential degradation profiles, it is shown that correcting in the first half of the mission is highly likely to result …

Experimental Study On The Effect Of Air Flow On Soap Bubble Formation, John M. Davidson

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Soap bubbles are a common interfacial fluid dynamics phenomenon having applications such as buoyant hollow spherical fillers and flow visualization of large scale airflows. In contrast to the dynamics of liquid drops in gas and gas bubbles in liquid, the dynamics of soap bubbles has not been well documented, possibly because soap bubbles have gas-liquid-gas interfaces. Having the thin-liquid-film interface seems to alter the characteristics of the bubble/drop creation process. Thus, the main objective of this study is to experimentally examine how airflow develops and interacts with the soap liquid film as the film stretches and finally collapses to pinch-off. …

Experimental Investigation Of The Active Flow Control On A Two-Dimensional Wind Turbine Airfoil, Guannan Wang

Dissertations - ALL

Wind turbine blades experience unsteady aerodynamic loading under various off-design conditions. The fatigue loading reduces the operational time of the wind turbine hence leads to an increase in the Cost of Energy (CoE) of the wind power. In this study, active flow control with unsteady blowing actuators was applied to a two-dimensional wind turbine airfoil to alleviate the unsteady aerodynamic loading and improve the aerodynamic performance, particularly under large scale freestream disturbances. A low speed, open jet aeroacoustic wind tunnel was designed and constructed based on an existing anechoic chamber for this investigation. A theoretical analysis based on a Blade …

Waveguiding Of Surface Phonon Polariton, Franklin Manene, Brian A. Lail, Edward C. Kinzel

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Metal losses lead to unacceptably low propagation lengths in THz and LWIR waveguides. While SPP based waveguides provide relatively good confinement and attenuation in the near-IR and visible these are insufficiently bound to the surface in the THz and LWIR. We study using surface phonon polaritons for waveguiding at these frequencies. An eigenmode approach was applied to model a hybrid waveguide structure at λ=10.6 μm. The results show that phonon-coupled hybrid waveguide of silicon carbide BCB and gold exhibit enhanced propagation length and confinement at LWIR. © 2013 IEEE.

Analysis Of An Inflatable Gossamer Device To Efficiently De-Orbit Cubesats, Robert A. Hawkins Jr.

Master's Theses

There is an increased need for spacecraft to quickly and efficiently de-orbit themselves as the amount of debris in orbit around Earth grows. Defunct spacecraft pose a significant threat to the LEO environment due to their risk of fragmentation. If these spacecraft are de-orbited at the end of their useful life their risk to future spacecraft is greatly lessened. A proposed method of efficiently de-orbiting spacecraft is to use an inflatable thin-film envelope to increase the body's area to mass ratio and thusly shortening its orbital lifetime. The system and analysis presented in this project is sized for use on …

Single Case Research Designs: An Effective And Efficient Methodology For Applied Aviation Research, Geoffrey R. Whitehurst

Dissertations

The purpose of this three-paper dissertation is to examine the potential of single case research designs (SCDs) as an appropriate and efficient experimental design for use in applied aviation research. In the current environment of dwindling resources, funding for experiments requiring large sample sizes, a normal requirement for between-group designs, is becoming difficult to find. However, the need to improve safety within the aviation industry is an ongoing requirement, especially as advances in technology continue have an impact on how the industry operates. SCDs are experimental designs that require very few participants and therefore have the potential to save time …