Aerospace Engineering Commons^™

Aerodynamics Of Wind Loading On Buildings, Kayla Burch

Honors Theses

A three-dimensional model of a one-story residential home, with an emphasis on the roof style and structure, was modeled using CATIA and then built and tested in the wind tunnel at Western Michigan University. The wind tunnel allowed an airflow over different style roofs to be tested at 100 mile per hour winds, strengths typical for hurricanes and other natural phenomena. The measured results show the lift and drag, along with the pressure gradient and the skin friction over the roofs. The effect of these aerodynamic characteristics of the building due to adding solar panel prototypes were also evaluated. The …

Mission Architecture Analysis: Exploring Long-Period Comets From Multiple Staging Orbits, Gabriel Prescinotti Vivan

Masters Theses

Objects that have retained pieces of information about the early Solar System are key to our understanding of its formation and evolutionary history. However, the high delta-V required to reach these objects, such as long-period comets or interstellar objects, makes designing an intercept mission at the time of detection impractical. In this thesis, multiple heliocentric staging orbits are explored to serve as departure positions for future missions, prior to objects’ detections. By utilizing more than one staging orbit concurrently, the set of objects that are reachable is expanded, therefore increasing mission feasibility. Delta-V maps are generated and superimposed; two-impulse burn …

Mechanical And Aerospace Engineering, 2019-2020, College Of Engineering And Applied Sciences

Mechanical and Aerospace Engineering News

• Letter from the Chair
• The MAE Staff
• Dr. Zachary Asher
• Alumni Excellence Academy Inductees
• From Sunway University to Success in America
• Student Experience at the Oshkosh Airventure
• Parker-Hannifin Donates New Hydraulic Trainers
• Electric Ducted Fan Lab for the Aircraft Propulsion Course
• MAE Faculty

Methodology Of Topology Optimization, Naziha Khandoker

Honors Theses

The need for lighter products is becoming increasingly essential as it cuts material cost and significant amount of weight, which is a key factor in the automotive and aerospace industries. Topology optimization allows us to achieve that by applying the concept to different structures with the goal of optimal distribution of material within finite volume design domain. Its algorithms selectively remove and relocate elements to achieve the optimum performance. This project performs a study on the effect of each design parameter over mechanical performance using Finite Element Analysis and applies it to set of wing attachment brackets. The optimized brackets …

Estimation Of The Fatigue Life Of Additively Manufactured Metallic Components Using Modified Strain Life Parameters Based On Surface Roughness, Peter Grohs

Masters Theses

In this study, a method is developed to estimate the effects of surface roughness on the fatigue life of additively manufactured titanium Ti6Al4V, aluminum 7075–T6, and steel 4340 alloys through modified strain life parameters using finite element analysis (FEA). This method is highly beneficial to the fatigue analysis of as-built additively manufactured metal components, which possess rough surfaces that reduce fatigue life significantly but are challenging to analyze directly using finite element simulation because of complex geometries, i.e., modeling an exact surface profile is arduous.

An effective stress concentration factor, incorporating roughness data, is defined to quantify their effects on …

A Reinforcement Learning Approach To Spacecraft Trajectory Optimization, Daniel S. Kolosa

Dissertations

This dissertation explores a novel method of solving low-thrust spacecraft targeting problems using reinforcement learning. A reinforcement learning algorithm based on Deep Deterministic Policy Gradients was developed to solve low-thrust trajectory optimization problems. The algorithm consists of two neural networks, an actor network and a critic network. The actor approximates a thrust magnitude given the current spacecraft state expressed as a set of orbital elements. The critic network evaluates the action taken by the actor based on the state and action taken. Three different types of trajectory problems were solved, a generalized orbit change maneuver, a semimajor axis change maneuver, …

Thermal Adaptation Of A Vacuum Chamber, Jacob Russell

Honors Theses

The process of adapting a preexisting vacuum chamber to perform thermal vacuum testing is a rare process in the testing industry. A closed vacuum system that was designed without thermal capacitance in mind will hinder the development of additional thermal system capabilities and prove difficult from a cost standpoint. Generally, building a thermal vacuum system from scratch will cost on the order of $10,000 to $100,000 depending on the system requirements regarding control and thermal capacitance within the chamber. This project will explore the cost of such an adaptation, attempting to minimize expense, and potentially provide the “Western Aerospace Launch …

Design Of A Thrust Stand For Electric Propulsion, Hannah Watts

Honors Theses

Thrust stands are the industry standard device for measuring the low levels of thrust generated by electric propulsion devices. Western Michigan University’s Aerospace Laboratory for Plasma Experiments is home to several electric propulsion devices and is in the process of obtaining a pulsed plasma thruster in partnership with the Western Aerospace Launch Initiative. The lab currently has no way of measuring the true thrust force generated by these devices. A thrust stand has been designed specific to the micro-Newton thrust range and the constraints inherent to the facilities in which it will operate.

Model Predictive Control Synthesis For The Innovative Control Effector Tailless Fighter Aircraft, Christopher Proctor

Masters Theses

A nonlinear model predictive control law was developed for the Lockheed Martin Innovative Control Effector tailless fighter aircraft to track way points. In general, aircraft are described by nonlinear dynamics that are dependent on the regime of flight. Additionally strict requirements on state and actuator constraints are common to all aircraft. Tailless aircraft are usually overdetermined systems, meaning solutions to control problems are not unique, and the system is non-affine. The proposed nonlinear control law considers those constraints during run-time, and solves the nonlinear control problem for a range of points within different flight regimes. The control law was developed …

Control Law Synthesis For Lockheed Martin’S Innovative Control Effectors Aircraft Concept, Cameron James Segard

Masters Theses

This thesis documents a conventional and modern flight control system design process carried out on a tailless aircraft Simulink model with innovative control effectors provided by Lockheed Martin. To set scope and design requirements a performance analysis was carried out to categorize the aircraft. Evaluation of open-loop dynamics reveled modal instabilities as well as state and control coupling. Flight condition dependent pole migration mapping reveled large changes in the aircraft’s static stability. Leading to the development of a four channel proportional-integral- derivative (PID) stability and control augmentation system (SCAS) controlling pitch-rate, roll-rate, side-slip angle, and airspeed states. PID gains are …

Mechanical And Aerospace Engineering, 2018-2019, College Of Engineering And Applied Sciences

Mechanical and Aerospace Engineering News

• Letter from the Chair
• Introducing Dr. Zachary D. Asher
• Department of Mechanical and Aerospace Engineering develops an engineering flight simulator
• Gear Sliding Loss Prediction
• Ph.D. student receives the prestigious NASA Earth and Space Science Fellowship
• NSF grant allows important materials research
• Student receives scholarship from gear industry
• Development of low cost/high volume micro/nano sensors and actuators
• Liou receives $204,000 NSF grant for neurological research
• Alexander Porter inducted into the Alumni Excellence Academy

Rotating Mount For Complex Fluid Flow Research, Kirsten Murphy

Honors Theses

Fluid flow around rotating objects is mathematically complex and there is currently limited experimental data on the subject. To make Western Michigan University capable of this research, a rotating wind tunnel mount was developed. The mount design was integrated into the existing setup at the Applied Aerodynamics Laboratory (AAL) to allow seamless transitions between different research projects. Non-rotating and rotating disk prototypes were created from 3D-printed materials to test the mount’s capabilities. Experimental data gathered from utilizing this rotating mount was analyzed to understand the aerodynamic effects on rotating disks in a fluid stream. From testing the rotating disk prototype …

Rotating Mount For Complex Fluid Flow Research, Kirsten Murphy

Honors Theses

Fluid flow around rotating objects is mathematically complex and there is currently limited experimental data on the subject. To make Western Michigan University capable of this research, a rotating wind tunnel mount was developed. The mount design was integrated into the existing setup at the Applied Aerodynamics Laboratory (AAL) to allow seamless transitions between different research projects. Non-rotating and rotating disk prototypes were created from 3D-printed materials to test the mount’s capabilities. Experimental data gathered from utilizing this rotating mount was analyzed to understand the aerodynamic effects on rotating disks in a fluid stream. From testing the rotating disk prototype …

Variable Reluctance Virtual Torque Sensor For Automotive Applications, Vivek Iddum

Masters Theses

Torque sensing has been realized as one of the critical aspects in improving the dynamic vehicle performance in automotive systems. This thesis mainly presents the work on the development of a novel torque measurement method based on the estimation of nth-order flywheel angular acceleration from the variable reluctance flywheel speed sensor pulses. The number of firings in the engine determine the order of the harmonic to be used for torque estimation. The nth-order flywheel angular acceleration is computed using a micro-controller with built in timer counter and an associated signal conditioning circuit. The pulses obtained from the flywheel speed sensor …

Hybrid Processes In Material Removal Of Hard And Brittle Materials, Hossein Mohammadi

Dissertations

New technologies demand new materials with better mechanical, optical, and thermal properties. Materials that are light weight, strong with high resistance to high temperatures, and compatible with a predetermined condition. Such materials usually are challenging to manufacture and process compared to widely available materials such as metals. Ceramics and semiconductors are considered extremely hard and brittle, making them very difficult to cut and manufacture. The other major and fast-growing type of materials are composites (including Ceramic Matrix Composites, CMC) that are also considered very challenging to machine. All these materials have many applications in major industries (i.e. electronics, aerospace, optics, …

Finite Element Modeling And Experimental Characterization Of Knot Configuration Effect On The Mechanical Performance Of Surgical Suture, Arz Y. Qwam Alden

Dissertations

Tendon injuries in orthopedic surgery and sports medicine are escalating; hence there is great interest in improving tendon repair. The integrity of tendon repair depends in part on a combination of suture material, suture size and knot configuration. Recent studies have indicated the failure of surgical knots as a failure mode during surgical repair. Further, there is still no consensus on the ideal (best/safest) surgical knot techniques. Also, this failure mode is related to stress concentrations, which cannot be easily established with traditional tensile testing. Most researchers have focused on the measurement and comparison of the gross structural response of …

Decomposition And Ionization Of Ionic Liquids, Forrest Grady Kidd Iii

Dissertations

The United States Air Force is interested in developing a situationally responsive space environment. In order to achieve this, dual-mode-propulsion will be utilized. A new class of propellants is being developed for this application based on energetic ionic liquids. Two ionic liquids of current interest are Hydroxylammonium Nitrate (HAN) and Hydroxyethylhydrazinium Nitrate (HEHN) due to their beneficial performance characteristics. The decomposition and ionization chemistry of these two species is investigated in this work. Using GAUSSIAN09 software, reactions with important radicals are explored through quantum chemistry. The energetics of reactions as well as the identity of key product complexes are given. …

Design Of An Electric Propulsion Thruster Breakout Box System, Ryan Powers

Honors Theses

When performing experiments in the Aerospace Laboratory for Plasma Experiments (ALPE), creating test setups and working with electrical equipment can become dangerous and tedious. A breakout box was required that ensures the ability to troubleshoot electrical problems, decrease the time needed to reconfigure equipment for an experiment, and decrease the potential for a safety hazard. The goal was to design a box that would house most of the equipment necessary to easily obtain current and voltage data from experiments in a safe, reliable manner. Three primary electrical components used in the circuit of the box were the current sensor, the …

Electromagnetic Radiation Shield For Spacecraft, Oseas Hudy-Velasco

Honors Theses

To protect astronauts from high-energy radiation during long-duration missions, an electromagnetic radiation shield was designed and sized for the Orion spacecraft with physical dimensions at a 1:100 scale and magnetic fields and particle energies at a ∼1:10833.3 scale. The electromagnetic radiation shield was simulated in the multi-physics software Comsol using the Magnetic Fields and Particle Tracing modules. The scale model used a DC amperage of 60 A with a 9-turn solenoid wound in three layers and the full-size system used a DC amperage of 6500 A and a 5-layer solenoid of 390 turns per layer. These models generated magnetic fields …

Land, Air, Sea, Rover (Lasr) - Unmanned Vehicle, Gabriel Prescinotti Vivan

Honors Theses

This senior design project encompassed the optimization of a previously built quadcopter, as well as the design of new components for additional functions and increased range of operations. The previous vehicle was designed to operate as a helicopter, land rover, and submarine. Although the vehicle operates successfully in these three environments, it is not very successful on transitioning between them, i.e. cannot take off from underneath water. This year’s project goals included optimizing the current vehicle so that it could transition seamlessly between its functions and adding an additional function: to be able to rover at the bottom of a …

Determination Of Chemical Notch, KChem On Aluminum And Steel When Subjected Under Slow Strain Rate Test In Corrosive Environment, Joshua Teo Lee Kuok

Masters Theses

When designing for any mechanical components or system, the question would arise as to how the material would react to the loads subjected on it? Would the component survive its service load? How would it react to environmental corrosion? To answer these questions, the technique used in this thesis paper is the Slow Strain Rate Test (SSRT) method. Aluminum and steel were chosen as the material to be tested in this paper. Al 7075-T651, and Al 6061-T651 was chosen due to its wide range of application, high strength to weight ratio and ease of machinability. It is highly used in …

Mechanical And Aerospace Engineering, 2017-2018, College Of Engineering And Applied Sciences

Mechanical and Aerospace Engineering News

• Letter from the Chair
• Introducing Dr. Jinseok Kim
• Use of 3D Printing at WMU Helps Borgess Cardiologist Plug Holes in the Heart
• Department of Mechanical and Aerospace Engineering Develops Semi-Virtual Reality Powered Wheelchair Simulator
• The Western Aerospace Launch Initiative (WALI)
• 2017 NSF I-Corps Experience of MAE team
• Matthew Baird's Internship Experiences at JPL and GRC
• More Department News
• Faculty Sabbaticals

Model Predictive Power Management Of A Hybrid Electric Propulsion System For Aircraft, Tyler J. Wall

Masters Theses

This work presents the switched optimal power flow control for an aircraft with a hybrid electric propulsion system. The propulsion system is a switched system that operates in either of two modes: (i) battery discharging and electric motor propelling and (ii) battery charging and electric motor generating. The aircraft model and components that form the hybrid propulsion system are modeled as either an algebraic power source/sink or as a dynamic model with appropriate power and state interconnections. With the system model defined, a model predictive control power management strategy is set fourth which minimizes a performance index that includes altitude …

Experimental Study Of Global Luminescent Oil-Film (Glof) Skin-Friction Meter On Delta Wings, Patrick Nicholas Wewengkang

Masters Theses

This thesis describes how the Global Luminescent Oil-Film (GLOF) Skin-Friction Meter can be applied experimentally to extract skin-friction from a set of images. In this study, the effect of oil viscosity, experimental sample size, and step size were considered to see how they would affect the extracted skin-friction using the GLOF method. These results were then compared to published literature on skin-friction diagnostics of delta wings, based on observations of critical characteristics such as reattachment and separation lines. Delta wings of 50°, 55°, 60°, 65°, and 70° sweep angles were built and placed in the Small Wind Tunnel (SWT) at …

Development Of Empirical And Virtual Tools For The Study Of Bicycle Safety, Brent Kostich

Masters Theses

Bicycles have been used as a form of non-motorized transportation for several hundred years. Recently, their use in the transportation realm has been reinvigorated because of growing population densities and efforts to improve environmental sustainability. However, a large deterrent for public use of the bicycle is concern over its level of safety in the transportation environment. The goal of this thesis is to develop two complementary research tools that advance the study of bicycle safety factors.

First, an instrumented probe bicycle (IPB) is constructed from the ground up. The bicycle is outfitted with an array of sensors that are integrated …

Atmospheric Microbial Community Sampling System For Varying Altitude Collection, Kenneth David Domingue

Masters Theses

The study of airborne microbial communities in the vertical atmosphere is an area of research in which very little data has been collected and analyzed. Developing a vehicle to house biological sampling equipment that collects, and mitigates contamination is required by a team of biology researchers to perform sampling of atmospheric microbial communities. This study uses a sampler box that is attached to aerostatic vehicles: zero pressure balloons and tethered balloon/kite structures. Zero pressure balloons are used for sampling at altitudes above 150 m above sea level, and tethered balloon/kite structures are used for sampling at 30 m and 150 …

Satellite Sequencing Optimization Using A Genetic Algorithm, Andrew Verstraete

Research and Creative Activities Poster Day

The problem of mission design for a robotic servicing satellite in geosynchronous Earth orbit (GEO) was investigated. A representative set of potential client satellites was selected, and operational needs were randomly assigned based on the average number of GEO retirements, anomalies, and repositioning maneuvers that currently occur each year. An objective function was developed to represent the value of servicing mission sequences, including client fees, time penalties, and operational risk. A genetic algorithm was then used to find sequences of operations on the potential client set that maximized the objective function’s value. Scenarios were analyzed with the database of satellites …

Satellite Sequencing Optimization And Observational Orbit Determination Using Genetic Algorithms, Andrew W. Verstraete

Masters Theses

The problem of mission design for a robotic servicing satellite in geosynchronous Earth orbit (GEO) was investigated. A representative set of potential client satellites was selected, and operational needs were randomly assigned based on the average number of GEO retirements, anomalies, and repositioning maneuvers that currently occur each year. An objective function was developed to represent the value of servicing mission sequences, including client fees, time penalties, and operational risk. A genetic algorithm was then used to find sequences of operations on the potential client set that maximized the objective function’s value. Scenarios were analyzed with the database of satellites …

Mechanical And Aerospace Engineering, 2016-2017, College Of Engineering And Applied Sciences

Mechanical and Aerospace Engineering News

• Letter from the Department Chair
• Mechanical and Aerospace Engineering Wins Grant from DENSO North America Foundation
• NSF $452,399 award to bring state-of-the-art instrument to WMU
• Faculty Research
• Faculty Summer Research
• Research in Fluid Mechanics and Aerodynamics
• Auto lab upgrades make it a premier teaching and research facility
• MAE faculty

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.