Matching Items (10)
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- All Subjects: MATLAB
- Creators: Mechanical and Aerospace Engineering Program
Description
Two of the most fundamental barriers to the exploration of the solar system are the cost of transporting material to space and the time it takes to get to destinations beyond Earth’s sphere of influence. Space elevators can solve this problem by enabling extremely fast and propellant free transit to nearly any destination in the solar system. A space elevator is a structure that consists of an anchor on the Earth’s surface, a tether connected from the surface to a point well above geostationary orbit, and an apex counterweight anchor. Since the entire structure rotates at the same rate as the Earth regardless of altitude, gravity is the dominant force on structures below GEO while centripetal force is dominant above, allowing climber vehicles to accelerate from GEO along the tether and launch off from the apex with large velocities. The outcome of this project is the development of a MATLAB script that can design and analyze a space elevator tether and climber vehicle. The elevator itself is designed to require the minimum amount of material necessary to support a given climber mass based on provided material properties, while the climber is simulated separately. The climber and tether models are then combined to determine how the force applied by the climber vehicle changes the stress distribution inside the tether.
ContributorsNelson, Alexander (Author) / Peet, Matthew (Thesis director) / Mignolet, Marc (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2022-05
Description
Psychedelics have received attention in research due to their therapeutic potential,
prompting a need for a deeper understanding of their effects. Perception, a cognitive process
involving sensory stimuli and interpretation, is known to be altered by psychedelics. This project aims to investigate body image perception under psychedelics' influence, utilizing virtual reality (VR) and motion capture technology. To validate findings and mitigate memory biases in the experiments by Helms-Tillery et al. (1991) VR can be employed to control stimuli and measure body location perception. Motion capture data serves as a reliable reference system, aiding in the translation of VR data. MATLAB scripts are developed to process motion capture data, defining body position accurately. Troubleshooting and debugging are crucial in ensuring data accuracy. The project culminates in a generalized code applicable to diverse experimental setups, facilitating spatial perception research and laying groundwork for psychedelic studies.
ContributorsBozzo, Isabella (Author) / Helms Tillery, Stephen (Thesis director) / Buneo, Christopher (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2024-05
Energy efficient optimal formation control of a multiple quadrotor UAV system with uncertain payload
Description
This thesis presents the design and simulation of an energy efficient controller for a system of three drones transporting a payload in a net. The object ensnared in the net is represented as a mass connected by massless stiff springs to each drone. Both a pole-placement approach and an optimal control approach are used to design a trajectory controller for the system. Results are simulated for a single drone and the three drone system both without and with payload.
ContributorsHayden, Alexander (Author) / Grewal, Anoop (Thesis director) / Berman, Spring (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Historical, Philosophical & Religious Studies, Sch (Contributor)
Created2022-05
Description
The objective goal of this research is to maximize the speed of the end effector of a three link R-R-R mechanical system with constrained torque input control. The project utilizes MATLAB optimization tools to determine the optimal throwing motion of a simulated mechanical system, while mirroring the physical parameters and constraints of a human arm wherever possible. The analysis of this final result determines if the kinetic chain effect is present in the theoretically optimized solution. This is done by comparing it with an intuitively optimized system based on throwing motion derived from the forehand throw in Ultimate frisbee.
ContributorsHartmann, Julien (Author) / Grewal, Anoop (Thesis director) / Redkar, Sangram (Committee member) / Barrett, The Honors College (Contributor) / School of International Letters and Cultures (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2022-05
Description
This thesis explores the melting optimization of phase change materials (PCMs) in a concentric pipe setup with a focus on improving heat transfer efficiency for latent heat thermal energy storage (LHTES) systems. The primary objective is to investigate the effects of varying the number of fins, as well as introducing bifurcations along the fin length, to optimize the time it takes to fully melt the PCM matrix. The work begins by verifying the accuracy of the Ansys Fluent simulations using the Stefan analytical solution, a well-established method for 1D melting processes. MATLAB was used to plot the Stefan solution, determining the time required to melt a 1mm block of ice with a boundary temperature slightly above freezing. This was subsequently compared to results obtained from Ansys Fluent, both of which showed consistency in melting times and temperature distributions, validating the simulation approach.
Next, thermal resistance modeling is utilized to establish both upper and lower bounds for melting times, considering the slowest and fastest possible rates. The analysis introduces the use of shape factors, a geometric parameter critical to determining the thermal resistance between the inner and outer pipes in the concentric setup. The derived thermal resistance and subsequent equations provide a conservative estimate of the slowest time to melt, which is ~38,078 seconds. Similarly, the fastest melting time is calculated by equating shape factors to convective heat transfer coefficients, yielding a much shorter time of ~1,339 seconds. These bounds provide a critical "gut check" for the results observed in the simulation phase. The first stage of optimization explores the effect of increasing the total number of fins in the concentric pipe setup. Initially, a base model with four fins was tested, and then simulations were conducted for setups with up to 13 fins. The total fin area was kept constant while adjusting the fin length accordingly. Results revealed that the optimal number of fins, in terms of minimizing the total melt time, falls between 5 and 6, with the fastest time achieved at 6 fins. This finding highlights that as the number of fins increases beyond this point, the effectiveness of heat transfer diminishes due to fin crowding. The second stage introduces bifurcations along the fins, which further improve heat transfer by extending more surface area into the PCM matrix. The bifurcations were analyzed at various points along the fin length, ranging from 20% to 80% of the total length. A detailed simulation study revealed that the optimal configuration consists of 5 fins with bifurcations beginning at 20% of the fin length, significantly reducing melt times compared to non-bifurcated setups. Overall, this research demonstrates that by optimizing both the number of fins and the introduction of bifurcations, substantial improvements can be made to the efficiency of PCM melting in LHTES systems. The findings offer important insights for the design of heat exchangers and thermal storage systems, emphasizing the importance of balancing geometric factors to maximize heat transfer.
ContributorsCerullo, Aiden (Author) / Wilbur, Joshua (Thesis director) / Wang, Robert (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor)
Created2024-12
Description
This paper describes the development of a software tool used to automate the preliminary design of aircraft wing structure. By taking wing planform and aircraft weight as inputs, the tool is able to predict loads that will be experienced by the wing. An iterative process is then used to select optimal material thicknesses for each section of the design to minimize total structural weight. The load analysis checks for tensile failure as well as Euler buckling when considering if a given wing structure is valid. After running a variety of test cases with the tool it was found that wing structure of small-scale aircraft is predominantly buckling driven. This is problematic because commonly used weight estimation equations are based on large scale aircraft with strength driven wing designs. Thus, if these equations are applied to smaller aircraft, resulting weight estimates are often much lower than reality. The use of a physics-based approach to preliminary sizing could greatly improve the accuracy of weight predictions and accelerate the design process.
ContributorsKolesov, Nikolay (Author) / Takahashi, Timothy (Thesis director) / Patel, Jay (Committee member) / Kosaraju, Srinivas (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-12
Description
This honors thesis explores and models the flow of air around a cylindrical arrow that is rotating as it moves through the air. This model represents the airflow around an archery arrow after it is released from the bow and rotates while it flies through the air. This situation is important in archery because an understanding of the airflow allows archers to predict the flight of the arrow. As a result, archers can improve their accuracy and ability to hit targets. However, not many computational fluid dynamic simulations modeling the airflow around a rotating archery arrow exist. This thesis attempts to further the understanding of the airflow around a rotating archery arrow by creating a mathematical model to numerically simulate the airflow around the arrow in the presence of this rotation. This thesis uses a linearized approximation of the Navier Stokes equations to model the airflow around the arrow and explains the reasoning for using this simplification of the fully nonlinear Navier Stokes equations. This thesis continues to describe the discretization of these linearized equations using the finite difference method and the boundary conditions used for these equations. A MATLAB code solves the resulting system of equations in order to obtain a numerical simulation of this airflow around the rotating arrow. The results of the simulation for each velocity component and the pressure distribution are displayed. This thesis then discusses the results of the simulation, and the MATLAB code is analyzed to verify the convergence of the solution. Appendix A includes the full MATLAB code used for the flow simulation. Finally, this thesis explains potential future research topics, ideas, and improvements to the code that can help further the understanding and create more realistic simulations of the airflow around a flying archery arrow.
ContributorsCholinski, Christopher John (Author) / Tang, Wenbo (Thesis director) / Herrmann, Marcus (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / School of Mathematical and Statistical Sciences (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
The purpose of this project was to create an algorithm to improve firearm aiming. In order to do so, a simulation of exterior ballistics – the bullet’s behavior between the firearm muzzle and the target – was created in MATLAB. The simulation of bullet trajectory included consideration of three forces: gravity, air drag, and Coriolis ‘force’. An overall equation of motion for the bullet in flight, comprising the effects of the aforementioned forces, was constructed using formulae and theory given in R. L. McCoy’s Modern Exterior Ballistics. For the project, a reference frame was defined based on firearm muzzle and target positions, and an aim vector described by two angles was defined to describe the direction of the firearm’s barrel. The simulations of bullet trajectory take into account eleven parameters: the two aim angles, initial bullet speed (commonly referred to as muzzle velocity), 3-D Cartesian components of wind velocity, air density, bullet diameter, bullet mass, latitude of the firing area, and azimuth of fire (a quantified compass direction of fire).
The user inputs target position, muzzle position, and estimated environmental parameters to the system. Then, an aim vector would be calculated to hit the target under estimated conditions. Because the eleven trajectory parameters likely cannot all be precisely known, this solution will have some error. In real life, the system would use feedback from real shots of a firearm to correct for this error. For this project, a real-world proxy simulation was created that had built-in random error and variations in the parameters. The correction algorithm uses the error data from all previous shots to calculate adjustments to the original aim vector, so that each successive shot becomes more accurate. The system was tested with specifications of a common rifle platform, with estimated parameters and variations for a location in Tempe, AZ (since data for an urban area is readily available compared to a point in the wilderness). Results from this testing revealed that the system can “hit” a 2-meter-radius circular target in under 30 shots. When the errors and variations in parameters were halved for the real-world stand-in simulation, the system could “hit” a circular target with 0.55 meter radius in less than 25 shots. After analysis, it was found that the corrected aim angles converged on values, suggesting that the correction algorithm functions as intended (taking into account all past shots). Generally, it was found that any reduction of the means and standard deviations of parameter error improved the ability of the system to hit smaller targets, or hit the same target with less shots.
The user inputs target position, muzzle position, and estimated environmental parameters to the system. Then, an aim vector would be calculated to hit the target under estimated conditions. Because the eleven trajectory parameters likely cannot all be precisely known, this solution will have some error. In real life, the system would use feedback from real shots of a firearm to correct for this error. For this project, a real-world proxy simulation was created that had built-in random error and variations in the parameters. The correction algorithm uses the error data from all previous shots to calculate adjustments to the original aim vector, so that each successive shot becomes more accurate. The system was tested with specifications of a common rifle platform, with estimated parameters and variations for a location in Tempe, AZ (since data for an urban area is readily available compared to a point in the wilderness). Results from this testing revealed that the system can “hit” a 2-meter-radius circular target in under 30 shots. When the errors and variations in parameters were halved for the real-world stand-in simulation, the system could “hit” a circular target with 0.55 meter radius in less than 25 shots. After analysis, it was found that the corrected aim angles converged on values, suggesting that the correction algorithm functions as intended (taking into account all past shots). Generally, it was found that any reduction of the means and standard deviations of parameter error improved the ability of the system to hit smaller targets, or hit the same target with less shots.
ContributorsReyes, Joshua De Leon (Author) / Grewal, Anoop Singh (Thesis director) / Murthy, Raghavendra N. (Committee member) / Mechanical and Aerospace Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2019-05
Description
Monatomic gases are ideal working mediums for Brayton cycle systems due to their favorable thermodynamic properties. Closed Brayton cycle systems make use of these monatomic gases to increase system performance and thermal efficiency. Open Brayton cycles, on the other hand, operate with primarily diatomic and polyatomic gases from air and combustion products, which have less favorable properties. The focus of this study is to determine if monatomic gases can be utilized in an open Brayton cycle system, in a way that increases the overall performance, but is still cost effective.
Two variations on open cycle Brayton systems were analyzed, consisting of an “airborne” thrust producing propulsion system, and a “ground-based” power generation system. Both of these systems have some mole fraction of He, Ne, or Ar injected into the flow path at the inlet, and some fraction of monatomic gas recuperated and at the nozzle exit to be re-circulated through the system. This creates a working medium of an air-monatomic gas mixture before the combustor, and a combustion products-monatomic gas mixture after combustor. The system’s specific compressor work, specific turbine work, specific net power output, and thermal efficiency were analyzed for each case. The most dominant metric for performance is the thermal efficiency (η_sys), which showed a significant increase as the mole fraction of monatomic gas increased for all three gas types. With a mole fraction of 0.15, there was a 2-2.5% increase in the airborne system, and a 1.75% increase of the ground-based system. This confirms that “spiking” any open Brayton system with monatomic gas will lead to an increase in performance. Additionally, both systems showed an increase in compressor and turbine work for a set temperature difference with He and Ne, which can additionally lead to longer component lifecycles with less frequent maintenance checks.
The cost analysis essentially compares the operating cost of a standard system with the operating cost of the monatomic gas “spiked” system, while keeping the internal mass flow rate and total power output the same. This savings is denoted as a percent of the standard system with %NCS. This metric lumps the cost ratio of the monatomic gas and fuel (MGC/FC) with the fraction of recuperated monatomic gas (RF) into an effective cost ratio that represents the cost per second of monatomic gas injected into the system. Without recuperation, the results showed there is no mole fraction of any monatomic gas type that yields a positive %NCS for a reasonable range of current MGC/FC values. Integrating recuperation machinery in an airborne system is hugely impractical, effectively meaning that the use of monatomic gas in this case is not feasible. For a ground-based system on the other hand, recuperation is much more practical. The ground-based system showed that a RF value of at least 50% for He, 89% for Ne, and 94% for Ar is needed for positive savings. This shows that monatomic gas could theoretically be used cost effectively in a ground-based, power-generating open Brayton system. With an injected monatomic gas mole fraction of 0.15, and full 100% recuperation, there is a net cost savings of about 3.75% in this ground-based system.
Two variations on open cycle Brayton systems were analyzed, consisting of an “airborne” thrust producing propulsion system, and a “ground-based” power generation system. Both of these systems have some mole fraction of He, Ne, or Ar injected into the flow path at the inlet, and some fraction of monatomic gas recuperated and at the nozzle exit to be re-circulated through the system. This creates a working medium of an air-monatomic gas mixture before the combustor, and a combustion products-monatomic gas mixture after combustor. The system’s specific compressor work, specific turbine work, specific net power output, and thermal efficiency were analyzed for each case. The most dominant metric for performance is the thermal efficiency (η_sys), which showed a significant increase as the mole fraction of monatomic gas increased for all three gas types. With a mole fraction of 0.15, there was a 2-2.5% increase in the airborne system, and a 1.75% increase of the ground-based system. This confirms that “spiking” any open Brayton system with monatomic gas will lead to an increase in performance. Additionally, both systems showed an increase in compressor and turbine work for a set temperature difference with He and Ne, which can additionally lead to longer component lifecycles with less frequent maintenance checks.
The cost analysis essentially compares the operating cost of a standard system with the operating cost of the monatomic gas “spiked” system, while keeping the internal mass flow rate and total power output the same. This savings is denoted as a percent of the standard system with %NCS. This metric lumps the cost ratio of the monatomic gas and fuel (MGC/FC) with the fraction of recuperated monatomic gas (RF) into an effective cost ratio that represents the cost per second of monatomic gas injected into the system. Without recuperation, the results showed there is no mole fraction of any monatomic gas type that yields a positive %NCS for a reasonable range of current MGC/FC values. Integrating recuperation machinery in an airborne system is hugely impractical, effectively meaning that the use of monatomic gas in this case is not feasible. For a ground-based system on the other hand, recuperation is much more practical. The ground-based system showed that a RF value of at least 50% for He, 89% for Ne, and 94% for Ar is needed for positive savings. This shows that monatomic gas could theoretically be used cost effectively in a ground-based, power-generating open Brayton system. With an injected monatomic gas mole fraction of 0.15, and full 100% recuperation, there is a net cost savings of about 3.75% in this ground-based system.
ContributorsBernaud, Ryan Clark (Author) / Dahm, Werner (Thesis director) / Wells, Valana (Committee member) / Mechanical and Aerospace Engineering Program (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
Description
The objective of this project was to analyze the flight of a red-tailed hawk in order to figure out how it remains stable in flight, and to determine if it had any advantages over conventional aircraft that could be implemented into future aircraft design. The analysis was performed by solving a six degree of freedom model (6DOF) in MATLAB with the use of Simulink. The twelve equations of motion that describe the 6DOF had to be built in Simulink, and parameters describing the bird’s performance and geometry had to be found and implemented as well. In preparation for the project, a lot of research was conducted to see what others had come across and how they thought birds remain stable. Research was also conducted in order to better describe the red-tailed hawk in the model. The research was focused on the aerodynamics of birds, and ranged from finding lift curve slopes to finding the physical mechanisms behind how birds control themselves and remain stable. In the absence of a live red-tailed hawk specimen that could be studied, pictures and videos were used to obtain flight performance and geometric characteristics. Preliminary results from the model modeling the hawk’s open loop response showed that even with a configuration that was statically longitudinally stable, the bird’s velocity was unbounded and showed oscillations with large changes in magnitude. Since the velocity was unbounded, the position was also unbounded and both were reaching values that were unrealistic. The bird’s pitch rate was also constantly increasing. These results indicated that the hawk must be closing the loop and a controller for pitch rate and pitch angle had to be modeled. The gains of the controller were chosen to target the Butterworth poles. Integration of the controller into the existing model was successful and results showed that the rates and angles were controlled. Based on those results, it was confirmed that the bird was actively controlling itself to maintain orientation during descent. With a viable model constructed, it opens up the possibility of studying more aspects of the bird’s flight, such as lateral stability. For future study, there is opportunity to refine the aerodynamics model, explore lateral stability, and model the hawk’s guidance system as it hunts for prey.
ContributorsBialek-Kling, Ashton (Author) / Garrett, Frederick (Thesis director) / Hines, Taylor (Committee member) / Barrett, The Honors College (Contributor) / Mechanical and Aerospace Engineering Program (Contributor) / Dean, W.P. Carey School of Business (Contributor)
Created2025-05