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Nonlinear six degree-ofreedom simulator for a small unmanned aerial vehicleEdwards, Christopher Doyle 01 May 2010 (has links)
Aircraft modeling and simulation have become increasingly important in the areas of pilot training, safety and aircraft design, especially for unmanned aerial vehicles (UAVs). A userriendly, easily expandable, nonlinear six degree-ofreedom aircraft simulator for the Xipiter X-2C Xawk UAV was created to address these issues. The simulator will allow pilots to have an opportunity to train and gain experience in flying the aircraft even before it leaves the ground. In addition, it will allow for design modifications or new aircraft designs to be evaluated before time and money are spent on their implementation. This work can also serve as the basis for the development of control systems for the aircraft, such as a control augmentation system or autopilot.
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A Simulation Environment for a Personal Portable Power SystemMorrison, Shane Leland 30 April 2011 (has links)
With the increased requirements for personal portable power systems to be more capable and better matched to the load and the mission, manufacturers have become interested in improved methods for predicting the performance of these systems. Personal portable power systems must meet challenging energy and portability requirements that require better predictive knowledge of these systems in integrated systems with realistic mission scenarios. This thesis presents the development of a modeling and simulation environment to further expand and predict the needs and requirements of personal portable power systems. The proposed personal portable power system is a diverse system consisting of energy and power sources, controllers, a DC-DC converter, batteries, and loads. An outcome of this initial simulation environment development is a tool that can be used in future work to plan scenarios and tasks.
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Left Ventricular Strains during Late Filling in a Preclinical ModelPeles, Saar 01 January 2020 (has links)
Understanding the mechanisms governing left ventricular function and dysfunction is critical to analyze cardiovascular disorders and gaining insights into possible therapies. Left ventricular function can be evaluated using Magnetic Resonance Imaging (MRI). Cardiac displacements and corresponding strains are then computed from the imaging data. In measuring and assessing the left ventricle’s motion, images are taken either in the short axis (top-down) or long axis (side) views. In this project, we will use DENSE MRI data, which measures the displacements of individual tissue voxels during the cardiac cycle.
After extracting the myocardial tissue by segmenting the MR images, strains are computed by differentiating the displacement field in the radial direction (across the thickness of the heart wall), longitudinal direction (along the left ventricle long axis), and in the circumferential direction. Current approaches focus mainly on evaluating cardiac motion and strains during ventricular systole, when the ventricles contract and blood is pumped out of the heart ~\cite{srichai2009cardiovascular}. Our aim is to characterize strains during atrial systole, which corresponds to the late filling of the ventricles before the next contraction occurs. Understanding the deformation of the left ventricle during late filling is particularly important to evaluate the passive response of the myocardium, which is related to several cardiac diseases, such as heart failure with preserved ejection fraction and diabetic cardiomyopathy. During this study we will use preclinical data already acquired in healthy swine subjects. Our goal is to evaluate inter subject variability at peak atrial systole and how different segmentations (intra and inter observer variability) affect the computed strains.
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Eye of the Fish : Integration av kamera, video feed och lagring i ett komplex forskningsprojektJohansson, Linnea, Andersson, Robin January 2023 (has links)
Det har länge funnits arbete med att minimera miljöförstöringen av vattenkvaliteten.För att minimera skadorna som vattnet utsätts för bör det utföras fler tester och undersökningar på olika platser så att man kan åtgärda dessa så fort som möjligt. I dagsläget utförs dessa tester någon gång om året eller mindre, då det är tidskrävande att göra dessa tester. Ett studentprojekt på Halmstads Högskola, CatFish Projekt, arbetar med att automatisera undersökning av vattenkvaliteten med hjälp av automatiserade robotar. Fokuset inom detta projekt kommer att ligga på att programmera ett program som samlar in data från en kamera som sitter på en av CatFish:s tre robotar, Fish. Programmet är skrivit i Bash-script och använder sig utav multimediaramverket GStreamer. Programmet ska därefter överföra den uppsamlade data och lagra informationen på en hårddisk som är kopplad till roboten Cat. Informationen som samlats in kommer att göras om till en fullständig video som sedan kan analyseras vi ett senare tillfälle. För att transportera över informationen användes UDP ihop med RTP. Projektet fördjupar sig i videokvalitet och använder sig utav olika mätningsalgoritmer som MSE, SNR och PSNR för att få fram den bästa videokvaliteten.
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Analysis of Transfer Trajectories Utilizing Sequential Saturn-Titan AerocapturesPayne, Isaac Lee 03 July 2023 (has links)
This thesis aims to investigate the potential of a transfer orbit using successive aerocaptures at Saturn and Titan to establish a science orbit around Titan. Titan is an Earth-like moon with a dense atmosphere and organic compounds present. It has many similarities with Earth that are useful to study such as superrotation. Superrotation is when the atmosphere rotates faster than the body it surrounds. In order to study Titan, we need to establish an orbit around it. The Saturn system is distant from Earth, 8.5 Astronomical Units (AU) which makes it difficult to reach from a time and velocity point of view. We propose to use an aerocapture at Saturn to intercept Titan with lower relative velocity in order to perform an aerocapture at Titan. The analysis was performed in primarily MATLAB to simulate the orbits. The results of this showed that we can aerocapture a spacecraft at Saturn and arrive at Titan within roughly 4 to 8 km/s relative velocity regardless of the incoming hyperbolic excess velocity at the Saturn system. This can be improve upon by using intermediate transfer orbits, such as bi-elliptics, to arrive with even lower relative velocities to Titan of as low as 1 km/s. The drag acceleration experienced during the Saturn aerocapture had peak values of between 0.2 and 1.4 g's and acceleration over 50% of the peak is experienced between 6.8 and 8 minutes. This capture method has the potential to make Titan more easily accessible and allow for scientific study of a clear target for improving our understanding of Earth-like processes on other bodies in our solar system. / Master of Science / This thesis aims to investigate the potential of a transfer orbit using successive aerocaptures at Saturn and Titan to establish a science orbit around Titan. Aerocapturing is utilizing the atmosphere of a body to slow down a spacecraft. Titan is an Earth-like moon with a dense atmosphere and organic compounds present. It has many similarities with Earth that are useful to study such as superrotation. Superrotation is when the atmosphere of a body rotates faster than the body it surrounds. In order to study Titan, we need to establish an orbit around it. The Saturn system is distant from Earth, 8.5 Astronomical Units (AU) which makes it difficult to reach from a time and velocity point of view. It takes a large amount of time to get there so we attempt to get there faster by increasing velocity. This means we arrive at the Saturn system with a large amount of velocity that we need to counter-act in order to orbit. We propose to use an aerocapture at Saturn to intercept Titan with lower velocity in order to perform another aerocapture at Titan to slow into an orbit. The analysis was performed in primarily MATLAB to simulate the orbits. The results of this showed that we can aerocapture a spacecraft at Saturn and arrive at Titan within roughly 4 to 8 km/s regardless of the incoming velocity to the Saturn system. This can be improve upon by using intermediate transfer orbits, after capturing at Saturn, to arrive with even lower velocities at Titan of as low as 1 km/s. The drag acceleration experienced during the Saturn aerocapture had peak values of between 0.2 and 1.4 g's and acceleration over 50% of the peak is experienced between 6.8 and 8 minutes. This is relatively gentle for an aerocapture and means the spacecraft likely will not require significant structural support. This capture method has the potential to make Titan more easily accessible and allow for scientific study of a clear target for improving our understanding of Earth-like processes on other bodies in our solar system.
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Development Of A Motor Speed Control System Using Matlab And Simulink, Implemented With A Digital Signal ProcessorKlee, Andrew 01 January 2005 (has links)
This thesis describes an improved methodology for embedded software development. MATLAB and Simulink allow engineers to simplify algorithm development and avoid duplication of effort in deploying these algorithms to the end hardware. Special new hardware targeting capabilities of MATLAB and Simulink are described in detail. A motor control system design served to demonstrate the efficacy of this new method. Initial data was collected to help model the motor in Simulink. This allowed for the design of the open and closed loop control systems. The designed system was very effective, with good response and no steady state error. The entire design process and deployment to a digital signal processor took significantly less time and effort than other typical methods. The results of the control system design as well as the details of these development improvements are described.
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Aerospike Rocket Motor Structural WebbingBrock, Andrew 01 February 2015 (has links) (PDF)
A labscale hybrid rocket motor test stand has been developed for research at Cal Poly. The primary focus of research using this rig has been the development of regenerative cooling techniques using nitrous oxide as coolant and oxidizer, as well as validation of technologies relating to the annular aerospike nozzle. In order to prevent undesirable deflection of the cantilevered spike, a structural stiffening web, referred to as “The Spider,” is proposed. The Spider resembles a three-spoked wheel, with the aerospike held by the inner hub and the chamber walls abutting the outer radius.
The Spider, placed upstream of the nozzle, is subject to thermal loads due to radiation and convection from the gases, and conduction from the outer annulus, as well as mechanical loads from thermal expansion and gas flow. Simulation tools are developed in three phases to produce an accurate model of the spatio-temporal distribution of these loads.
A prototype of the Spider instrumented with thermocouple probes is designed, manufactured, and subjected to a series of hotfire tests. Results from three experimental runs are gathered and compared to simulated results. Good agreement is shown for the most part between the two datasets, with a single noticeable discrepancy for one measured temperature location. The high fidelity in the mean rate of temperature change for all stations indicates that the convective heat load is accurately modeled.
The simulation results, confirmed by experiment, indicate that in order for the Spider to survive in the steady-state during an actual burn, an active cooling strategy is necessary. Two actively cooled concept designs are presented and discussed, and future avenues of research are suggested.
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CUBESAT Mission Planning ToolboxCastello, Brian 01 June 2012 (has links) (PDF)
We are in an era of massive spending cuts in educational institutions, aerospace companies and governmental entities. Educational institutions are pursuing more training for less money, aerospace companies are reducing the cost of gaining ight heritage and the government is cutting budgets and their response times. Organizations are accomplishing this improved efficiency by moving away from large-scale satellite projects and developing pico and nanosatellites following the CubeSat specifications. One of the major challenges of developing satellites to the standard CubeSat mission requirements is meeting the exceedingly tight power, data and communication constraints.
A MATLAB toolbox was created to assist the CubeSat community with understanding these restrictions, optimizing their systems, increasing mission success and decreasing the time building to these initial requirements. The Toolbox incorporated the lessons learned from the past nine years of CubeSats' successes and Analytical Graphics, Inc. (AGI)'s Satellite Tool Kit (STK). The CubeSat Mission Planning Toolbox (CMPT) provides graphical representations of the important requirements a systems engineer needs to plan their mission. This includes requirements for data storage, ground station facilities, orbital parameters, and power. CMPT also allows for a comparison of broadcast (BC) downlinking to Ground Station Initiated (GSI) downlinking for payload data using federated ground station networks. Ultimately, this tool saves time and money for the CubeSat systems engineer
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Steam consumption minimization using genetic algorithm optimization method: an industrial case studyAlabdulkarem, A., Rahmanian, Nejat 13 May 2020 (has links)
yes / Condensate stabilization is a process where hydrocarbon condensate recovered from natural gas reservoirs is processed to meet the required storage, transportation, and export specifications. The process involves stabilizing of hydrocarbon liquid by separation of light hydrocarbon such as methane from the heavier hydrocarbon constituents such as propane. An industrial scale back-up condensate stabilization unit was simulated using Aspen HYSYS software and validated with the plant data. The separation process consumes significant amount of energy in form of steam. The objectives of the paper are to find the minimum steam consumption of the process and conduct sensitivity and exergy analyses on the process. The minimum steam consumption was found using genetic algorithm optimization method for both winter and summer conditions. The optimization was carried out using MATLAB software coupled with Aspen HYSYS software. The optimization involves six design variables and four constraints, such that realistic results are achieved. The results of the optimization show that savings in steam consumption is 34% as compared to the baseline process while maintaining the desired specifications. The effect of natural gas feed temperature has been investigated. The results show that steam consumption is reduced by 46% when the natural gas feed temperature changes from 17.7 to 32.7°C. Exergy analysis shows that exergy destruction of the optimized process is 37% less than the baseline process.
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Solar-powered direct contact membrane distillation system: performance and water cost evaluationSoomro, M.I., Kumar, S., Ullah, A., Shar, Muhammad A., Alhazaa, A. 12 December 2022 (has links)
Yes / Fresh water is crucial for life, supporting human civilizations and ecosystems, and its
production is one of the global issues. To cope with this issue, we evaluated the performance and cost
of a solar-powered direct contact membrane distillation (DCMD) unit for fresh water production in
Karachi, Pakistan. The solar water heating system (SWHS) was evaluated with the help of a system
advisor model (SAM) tool. The evaluation of the DCMD unit was performed by solving the DCMD
mathematical model through a numerical iterative method in MATLAB software®. For the SWHS,
the simulation results showed that the highest average temperature of 55.05 ◦C and lowest average
temperature of 44.26 ◦C were achieved in May and December, respectively. The capacity factor and
solar fraction of the SWHS were found to be 27.9% and 87%, respectively. An exponential increase
from 11.4 kg/m2
·h to 23.23 kg/m2
·h in permeate flux was observed when increasing the hot water
temperatures from 44 ◦C to 56 ◦C. In the proposed system, a maximum of 279.82 L/day fresh water
was produced in May and a minimum of 146.83 L/day in January. On average, the solar-powered
DCMD system produced 217.66 L/day with a levelized water cost of 23.01 USD/m3 / This research was funded by the Researcher’s Supporting Project Number (RSP-2021/269), King Saud University, Riyadh, Saudi Arabia.
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