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banazadeh--afshin
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A Complexity-Based Model for Cost Estimation of Jet UAVs
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
Cost Estimation plays an essential and role in UAV (Unmanned Aerial Vehicles) Projects. By increasing the complexity of new unmanned systems, the importance of this task augments. Additionally, up to now, a comprehensive approach has not been adopted internationally. But in parallel a number of international companies and organizations has developed specific methods by themselves; confined to their corporate.
This project pursues developing a complexity-based model for cost estimation of unmanned aerial vehicles, especially Jet UAVs. However, it’s anticipated that this model may be utilized for all kind of systems, but it seems that jet UAVs use it with a better and more reliable...
This project pursues developing a complexity-based model for cost estimation of unmanned aerial vehicles, especially Jet UAVs. However, it’s anticipated that this model may be utilized for all kind of systems, but it seems that jet UAVs use it with a better and more reliable...
Modeling and Flight Controller Design of an Insect-Like Flapping Wing in Hover
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
There are many applications for micro aerial vehicles (MAV) and in nature they are flying as birds and insects. It can be said that a MAV that can mimic flying capabilities of birds and insects can be used as a solution for flying in low Reynolds number regimes. It seems that Flapping Wing MAVs have better performance than fixed and rotary wings MAV in low Reynolds number regimes. So far there haven’t been many theories and methods introduced for controlling flapping wing MAVs and many researches failed to provide a convenient way for designing an effective controller. On the other hand, models presented in literature for aerodynamics, dynamics and kinematics of flapping wing are not...
Aircraft Drag Determination in Frequency Domain Using Parametric Identification Methods
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
Determination of drag force is one of the most difficult activities in the design and development of an aircraft. Accurate estimation of drag force is very important in design studies and needs to be estimated over and over during the design trade-offs. Importance of the determination of drag force, from the performance viewpoint, is an important stage in development and evaluation of an aircraft behavior and if the thrust and drag forces are well determined, the other performance characteristics could be easily estimated. Different methods are introduced for determination of drag using flight test or system identification methods in the time domain owing some limitations, disadvantages or...
Trajectory Optimization of Micromechanical Flying Insect
,
M.Sc. Thesis
Sharif University of Technology
;
Banazadeh, Afshin
(Supervisor)
Abstract
In this work, A new hybrid approach is presented to optimize a trajectory of Micromechanical Flying Insect in an obstacle reach environment. Here, a singleobjective Evolutionary Algorithm is utilize for finding solutions corresponding to multiple conflicting goals, which include minimizing the length of the path while maximizing safety margin by avoiding hard and non-moving obstacles. On the other hand, dynamic constraints of Micromechanical Insect such as maximum and minimum attitude angles and speed should be taken into account. In order to reduce the computational cost, a novel hybrid two-layer procedure is suggested for trajectory optimization. In the first layer, the algorithm generates...
Adaptive Controller Design for Ducted Fans in Vertical Plane Phases
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
Ducted fan vertical take-off and landing (VTOL) aerial vehicles have drawn many attentions in the world because of their capability to offer high power to weight ratio for a certain vehicle diameter relative to open rotors or helicopters. However, due to inherent uncertainties in dynamics and inefficient and poor quality responses, significant control challenges are still unsolved and exciting fields for research. In the current study, a nonlinear dynamic model is proposed for the controller design purpose. This model is validated against simulation by performing several standard scenarios. An adaptive control method, named model reference (MRAC), is utilized to design a perfect controller...
Captive System Identification of Coanda-Effect Aerial Vehicle in Hover
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
Identification of dynamic behavior and extraction of mathematical model for aerial vehicle is important in design, test and evaluation processes. Due to explosion of unmanned vehicles industry in recent years, many innovative aerial concepts is introduced. Coanda-effect air vehicle is one of these novel ideas which is similar to flying saucers. In this study, an experimental scale model of this air vehicle is designed, built and tested with purpose of identifying the linear dynamic model of the vehicle, using the frequency domain identification methods. Performing the system Identification in hover requires a stable hovering capability in the vehicle. Given the inherent instabilities of...
Dynamic Model Identification of a 4th Generation Turbojet Engine’s FCU Using Parametric Frequency Response Analysis
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
In this thesis, dynamics of a turbojet’s fuel control unit is studied for the nature and the range of its inputs and outputs. Then, inputs and outputs involved in the system identification process are determined. Tools needed for the application of the input and the signal data sampling are recognized, and henceforth, with the appropriate input applied and the frequency-domain system identification process carried out, desired linear transformation functions representing dynamics of the fuel control unit are found. Using these transformation functions, the fuel control unit is simulated to be converted to an electronic control unit
Minimum-Distance Collision-Free Trajectory Generation for Formation Flying Satellites Using a Hybrid Path-Planning Algorithm
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
The formation flight of satellites corresponds to a group of small satellites, performing the mission of a presumed larger and more expensive satellite. Usually mission designers tend to put these satellites in such orbital configurations that their trajectories do not intersect. Although a stable configuration in a certain collision-free orbit is desirable for long term purposes, most of the missions including maneuvers like forming or changing a configuration and inserting new satellites need to be planned using a proper path planning algorithm. In this thesis, a path planning algorithm is suggested that acquires the optimal and impact-free trajectories for a group of satellites for...
Development of Rapid Evaluation and Optimization Software for Aircraft Conceptual Design
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
Classical methods in aircraft conceptual aircraft design have some deficiencies in such as low accuracy in aerodynamic derivatives estimation and incapability of verifying flight handling quality. Moreover, application of experimental equations and dependence on statistical data are other drawbacks of classical methods which are accounted as big challenges in development of unusual aircrafts. In this research, a comprehensive, rapid and practical software is developed in order to promote the conceptual aircraft design. This software provides a platform to perform various tasks such as aerodynamic measurement, nonlinear simulation, system identification and optimization simultaneously. In...
Development of an Optimal Path Planning Algorithm for Aerial Robots Based on GPOPS Program
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
In this thesis the problem of path planning for aerial robots,specifically the UAVs, is studied. Some software packs aiming to perform optimal path planning are already published worldwide. In this thesis, these software are investigated and UAV path planning is done by them. In UAV path planning using these software, due to the high number of equations, number of constraints in solution increases and even in a simple problem, the process of solving becomes difficult for software. Among introduced software packs, “GPOPS”, which uses pseudospectral methods, is chosen as the best. Avoiding obstacles in different problems is checked. Obstacle avoidance and waypoint tracking at the same time,...
Modelling, System Identification and Controllers Design of a Coanda Air Vehicle
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
In this study, the two rigid body modelling of a Coanda air vehicle (one rigid includes rotor and propeller and the second rigid includes the other parts of it) has been developed using Newton’s and Euler’s laws, and its motion was simulated in climb and forward flight conditions. Air vehicle propulsion force and moment have been modelled by employing the blade element momentum theory. In order to model the forces acting on the air vehicle, the drag force has been estimated by the results of analytical and computational fluid dynamics methods for the case of climb flight and by using experimental data of a cylindrical body for the forward flight. For modelling the control surfaces of this...
Ekranoplan Design Survey, Determination and Enhancement of Flying Qualities characteristics Through Stability Alalysis
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
During the last five decades, interest in High Speed Marine Vehicleshas been increasing for both commercial and military use, leading to newconfgurations and further development of already existing configurations to fill the gap between the low speed ships by high payload capacity to low construction cost, and high speed aircrafts by low payload capacity to high construction cost. Therfore Wing-In-Ground effect crafts (WIG)were introduced as the new marine vehicles family memberwhich have the potential for payload capacities closer to fast marine crafts and the cost of construction is much lower than aircraftswhile they are capablefly close to the water surface. On the whole, in this...
Control Effectiveness of a Ducted-fan UAV using Linear, Adaptive and MPC Controllers in Specified Flight Conditions
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
Nowadays, vertical take-off and landing (VTOL) UAVs are widely used in various commercial and military applications due to its high flying capabilities. RMIT VTOL is a special design of this family. This bird has a small size and low weight and along with the vertical takeoff and landing capabilities, it also has the ability to fly at high speed Cruise.
The overall objective of this project is to design and evaluate the efficiency of the proposed three control methods that are linear, predictive and adaptive on the dynamic model of this bird. Thus, the first part of the project is obtaining a dynamic model with sufficient detail for the dedicated bird. This model consists of different...
The overall objective of this project is to design and evaluate the efficiency of the proposed three control methods that are linear, predictive and adaptive on the dynamic model of this bird. Thus, the first part of the project is obtaining a dynamic model with sufficient detail for the dedicated bird. This model consists of different...
Adaptive Attitude and Position Control of a Rigid Body Insect-Like Flapping Wing
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
In this study, adaptive control of attitude and position of a rigid body insect-like flapping wing is investigated. For this purpose, a non-linear dynamic and time varying modeling and simulation is carried out initially with six degrees of freedom, and then the accuracy of the simulation is evaluated during different test cases. In order to design the controller, non-linear and time varying dynamic is transformed into non-linear and time-invariant dynamic using theory of averaging. Then, a non-linear controller is designed based on Lyapunov stability theory. Due to the inefficiency of the aforementioned controller under disturbances and unknown uncertainties in the model, an adaptive...
A Novel Design for Aerial Robots to Enhance Flight Performance
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
The purpose of this research is the conceptual design of an aerial robot that has the ability to reach different locations without changing its horizontal attitude. The main missions of the aerial robots are monitoring and delivery, in which none of them requires the robot to leave its horizontal attitude. The main task of the robot is to deliver the goods to the specified points. In order to do this, it must have an appropriate container for carrying the cargo, high safety to prevent damage to the cargo and individuals, the ability to carry out missions when one of the subsystems exits, and the appropriate flight speed for Deliver cargo to the customer as fast as possible. All of the...
Development of Neuro-Fuzzy Based Self-Adaptive Flight Control System in the Presence of Internal and External Disturbances
, Ph.D. Dissertation Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
A comprehensive adaptive flight control system in the presence of internal and external disturbances is introduced in this dissertation. In this regard, two different approaches, namely, a centralized model and a multi-model structure are developed using the capabilities of neuro-fuzzy systems in order to identify the dynamic model of an air vehicle after the fault occurrence in the simultaneous presence of model uncertainties and external disturbances. Subsequently, a Model Predictive Control (MPC) approach is designed for the identified model, which can satisfactorily deal with nonlinear and multi-variable nature of the system. In addition, system constraints can be effectively considered...
Stability Analysis of Nonlinear Periodically Time-Varying Dynamic Systems By Studying Typical Insect-Like Flapping Wing
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
Designing Nonautonomous periodic systems such as helicopters, multirotors, monocopters or the dynamics of flapping wings requires stability analysis and careful examination in order to identify and determine their dynamic behaviour. In practice, analysis and design are interdependent and the design of nonlinear control systems involves an iterative process. To know the importance of identifying and to accurately implement methods to analyse this kind of systems in the field of aerospace, the flapping wing can be a good example. The issue of stability and the control of the flapping wings have not yet had a clear solution, and the current research including controller design based on linear...
Learning Algorithms in Trajectory Tracking to be Applied to Fixed-Wing UAVs
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
The aim of this study is to develop a new algorithm to perform high performance and precise maneuvers for variety of fixed-wing UAVs. Iterative learning in conjunction with an adaptive control technique is developed here for this purpose. In this research, the guidance and control laws are initially developed by classic algorithms that exist in most of commercial autopilot systems. Then, the learning algorithm is combined with the classic autopilot system to improve trajectory tracking performance. The algorithms have been tested by simulation in the loop technique, utilizing Simulink and X-Plane software. So, the navigation data was provided by the X-Plane, solving dynamic equations, and...
LQG Controller Design for Hover Flight Based on Model Helicopter System Identification, Using X-Plane
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
The subject of this study is design of a linear quadratic Gaussian controller based on identification of dynamic behavior of unmanned model helicopter “Raptor” in its hover flight. To achieve this end, first, the helicopter linear transfer functions are identified with frequency response method by applying specific inputs to the model of Raptor in the X-Plane software and receiving system outputs via Simulink. Next, using the identified dynamic model of the helicopter, an optimum linear controller is designed for hover flight. As an optimum linear controller needs all the state variables, a Kalman filter is utilized to estimate them, using outputs of various sonsors such as GPS and gyro....
Efficiency Analysis of Principal Soft Computing Techniques for Noise Cancellation
, M.Sc. Thesis Sharif University of Technology ; Banazadeh, Afshin (Supervisor)
Abstract
In this thesis, LMS, NLMS, RLS, ADALINE and ANFIS as five adaptive noise removal methods have been studied with a software application approach. The aim of this study is to obtain the best method to remove noise in terms of signal to noise ratio (SNR) improvement as well as the speed of convergence. In this regard, firstly by applying a frequency sweep input, which is contaminated with white noise, the performance of these algorithms are investigated. Then, an audio signal is utilized as the target input, and the performance of the corresponding algorithms have been analyzed in aspect of filter order and learning coefficient. The results show that by increasing the order of filter and...