Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 5 of 5
Full-Text Articles in Aerospace Engineering
Systematic Methods For The Design Of A Class Of Fuzzy Logic Controllers, Saad Y. Yasin
Systematic Methods For The Design Of A Class Of Fuzzy Logic Controllers, Saad Y. Yasin
Dissertations
Fuzzy logic control, a relatively new branch of control, can be used effectively whenever conventional control techniques become inapplicable or impractical. Various attempts have been made to create a generalized fuzzy control system and to formulate an analytically based fuzzy control law. In this study, two methods, the left and right parameterization method and the normalized spline-base membership function method, were utilized for formulating analytical fuzzy control laws in important practical control applications. The first model was used to design an idle speed controller, while the second was used to control an inverted control problem. The results of both showed …
Flight Control Failure Detection And Control Redistribution Using Multiple Model Adaptive Estimation With Filter Spawning, Michael L. Torres Jr.
Flight Control Failure Detection And Control Redistribution Using Multiple Model Adaptive Estimation With Filter Spawning, Michael L. Torres Jr.
Theses and Dissertations
In the current research, the MMAE with Filter Spawning and Control Redistribution (MMAE/FS/CR) are used together to identify failures and apply appropriate corrections. This effort explores the performance of the MMAE/FS/CR in different regions of the flight envelope using model and gain scheduling. The MMAE/FS/CR is able to detect complete and partial actuator/surface failures, as well as complete sensor failures. Once the actuator/surface failure is identified and the effectiveness is determined in the case of partial failures, proper control is applied in order to accomplish the desired pilot command. Improvements in the algorithm are required in order to enhance the …
Broadcast Vs Precise Gps Ephemerides: A Historical Perspective, David L. M. Warren
Broadcast Vs Precise Gps Ephemerides: A Historical Perspective, David L. M. Warren
Theses and Dissertations
In most recent years, both high-resolution imagery systems and images were only available to military and national security organizations. Distinctive changes within the commercial image industry allowed space-borne pioneers to provide high-resolution images. Space-borne Image Company's Ikonos satellite provides a 1-meter resolution for the past 3 years. Current development of .5-meter resolution will be offered in the near future. Access of these images is available in ground stations located worldwide in different regions. Studies have shown that these high quality images are eye-catching and may serve a purpose through its design; on contrary high cost and accessibility does not met …
Ins Aiding By Tracking An Unknown Ground Object, Mursy Polat
Ins Aiding By Tracking An Unknown Ground Object, Mursy Polat
Theses and Dissertations
The reduction of the navigation error in an inertial navigation system by optically tracking a ground object is investigated. Multiple observations of the ground object are used. The location of the ground object is assumed unknown. A careful analysis of the measurement situation at hand reveals that by optically tracking an unknown ground object using passive, bearings-only measurements, the aircraft's angle of attack and sideslip angle can be measured. Thus, two new independent measurement equations featuring the aircraft's angular navigation variables are obtained. Hence, by optically tracking over time an unknown ground object, inertial navigation system aiding is in fact …
An Examination Of Latency And Degradation Issues In Unmanned Combat Aerial Vehicle Environments, Shane A. Dougherty
An Examination Of Latency And Degradation Issues In Unmanned Combat Aerial Vehicle Environments, Shane A. Dougherty
Theses and Dissertations
Since the multidimensional knapsack problems are NP-hard problems, the exact solutions of knapsack problems often need excessive computing time and storage space. Thus, heuristic approaches are more practical for multidimensional knapsack problems as problems get large. This thesis presents the results of an empirical study of the performance of heuristic solution procedures based on the coefficients correlation structures and constraint slackness settings. In this thesis, the three representative greedy heuristics, Toyoda, Senju and Toyoda, and Loulou and Michaelides methods, are studied. The purpose of this thesis is to explore which heuristic of the three representative greedy heuristics perform best under …