International Refereed Journal of Engineering and Science (IRJES) is a leading international journal for publication of new ideas, the state of the art research results and fundamental advances in all aspects of Engineering and Science. IRJES is a open access, peer reviewed international journal with a primary objective to provide the academic community and industry for the submission of half of original research and applications
Dynamic aerodynamic structural coupling numerical simulation on the flexible ...ijmech
Most biological flyers undergo orderly deformation in flight, and the deformations of wings lead to complex fluid-structure interactions. In this paper, an aerodynamic-structural coupling method of flapping wing is developed based on ANSYS to simulate the flapping of flexible wing.
Firstly, a three-dimensional model of the cicada’s wing is established. Then, numerical simulation method of unsteady flow field and structure calculation method of nonlinear large deformation are studied basing on Fluent module and Transient Structural module in ANSYS,
the examples are used to prove the validity of the method. Finally, Fluent module and Transient Structural module are connected through the System Coupling module to make a two-way fluidstructure Coupling computational framework. Comparing with the rigid wing of a cicada, the
coupling results of the flexible wing shows that the flexible deformation can increase the aerodynamic performances of flapping flight.
EAGES Proceedings - K. V. Rozhdestvenskii 2Stephan Aubin
In 2001 Euroavia Toulouse organized a symposium on ground effect. We invited most of the Russian and German actors, and some experts from Holland, UK or France for a week of science around the subject of ekranoplans / flying boats. This was dedicated to students. A book was issued... and now that all copies have been sold for a while I am sharing this on LinkedIn for everyone.
Enjoy.
Stéphan AUBIN
This document summarizes the Hess-Smith panel method for analyzing aerodynamic forces on airfoils. It begins with background on aerodynamics and the different types of air flow. It then describes the 2D Hess-Smith panel method, which involves discretizing an airfoil shape into panels and calculating source strengths to model the air flow. The document provides the theoretical equations for calculating velocity potential and solving for source strengths. It concludes by explaining the Python code used to implement the 2D source panel method on a NACA 0010 airfoil.
Airfoil properties, shapes & structural dynamical features are described. Nomenclature or the classification types are presented along with the application.
Common methods for analysis of the structural dynamics on a wing or blade are presented along with the possible applications.
- The document describes a 3D software wreckage reconstruction system (3D-SWRPS) used to assist in investigating the 2002 crash of China Airlines Flight CI611.
- The 3D-SWRPS utilizes 3D modeling of wreckage recovered from the site, laser scanning, and a reference Boeing 747-200 model to reconstruct wreckage pieces in 3D.
- Over 160 wreckage pieces were scanned and reconstructed in 3D to determine fracture patterns and the aircraft breakup sequence.
EAGES Proceedings - K. V. Rozhdestvenskii 1Stephan Aubin
In 2001 Euroavia Toulouse organized a symposium on ground effect. We invited most of the Russian and German actors, and some experts from Holland, UK or France for a week of science around the subject of ekranoplans / flying boats. This was dedicated to students. A book was issued... and now that all copies have been sold for a while I am sharing this on LinkedIn for everyone.
Enjoy.
Stéphan AUBIN
Naca 2415 finding lift coefficient using cfd, theoretical and javafoileSAT Journals
Abstract In this paper we have studied the experimental characteristic graph of NACA 2415.The experimental graphs were taken from the book, “Theory of wing section” by IRA H. ABBOTT. We used these graphs for the validation of our results. Then we use CFD to simulate the experimental flow conditions and check the results and compare them with the experimental results. We meshed the airfoil in ICEM CFD so that the meshing is very precise. We then calculate the NACA 2415 airfoil’s lift at different angle of attack theoretically and using CFD analysis and compare them with the experimental values. We find the errors between experimental and CFD values as well as experimental and theoretical values. We used another simulation software called Javafoil and used it for comparison. Keywords: Experimental, CFD, Theoretical, Javafoil
This document presents a mathematical model for determining the minimum overtaking sight distance (OSDm) required for an ascending vehicle to safely pass another slower vehicle on a single lane highway with an incline. It defines sight distance, stopping sight distance, perception-reaction time and derives equations to calculate the reaction distance (d1), overtaking distance (d2), vehicle travel distance during overtaking (d3), and total minimum OSDm based on vehicle characteristics, road geometry, and coefficients of friction. The safe overtaking zone is defined as 3 times the minimum OSDm. The model accounts for effects of slope angle and aims to satisfy laws of mechanics for overtaking maneuvers on inclined two-way single lane highways.
Dynamic aerodynamic structural coupling numerical simulation on the flexible ...ijmech
Most biological flyers undergo orderly deformation in flight, and the deformations of wings lead to complex fluid-structure interactions. In this paper, an aerodynamic-structural coupling method of flapping wing is developed based on ANSYS to simulate the flapping of flexible wing.
Firstly, a three-dimensional model of the cicada’s wing is established. Then, numerical simulation method of unsteady flow field and structure calculation method of nonlinear large deformation are studied basing on Fluent module and Transient Structural module in ANSYS,
the examples are used to prove the validity of the method. Finally, Fluent module and Transient Structural module are connected through the System Coupling module to make a two-way fluidstructure Coupling computational framework. Comparing with the rigid wing of a cicada, the
coupling results of the flexible wing shows that the flexible deformation can increase the aerodynamic performances of flapping flight.
EAGES Proceedings - K. V. Rozhdestvenskii 2Stephan Aubin
In 2001 Euroavia Toulouse organized a symposium on ground effect. We invited most of the Russian and German actors, and some experts from Holland, UK or France for a week of science around the subject of ekranoplans / flying boats. This was dedicated to students. A book was issued... and now that all copies have been sold for a while I am sharing this on LinkedIn for everyone.
Enjoy.
Stéphan AUBIN
This document summarizes the Hess-Smith panel method for analyzing aerodynamic forces on airfoils. It begins with background on aerodynamics and the different types of air flow. It then describes the 2D Hess-Smith panel method, which involves discretizing an airfoil shape into panels and calculating source strengths to model the air flow. The document provides the theoretical equations for calculating velocity potential and solving for source strengths. It concludes by explaining the Python code used to implement the 2D source panel method on a NACA 0010 airfoil.
Airfoil properties, shapes & structural dynamical features are described. Nomenclature or the classification types are presented along with the application.
Common methods for analysis of the structural dynamics on a wing or blade are presented along with the possible applications.
- The document describes a 3D software wreckage reconstruction system (3D-SWRPS) used to assist in investigating the 2002 crash of China Airlines Flight CI611.
- The 3D-SWRPS utilizes 3D modeling of wreckage recovered from the site, laser scanning, and a reference Boeing 747-200 model to reconstruct wreckage pieces in 3D.
- Over 160 wreckage pieces were scanned and reconstructed in 3D to determine fracture patterns and the aircraft breakup sequence.
EAGES Proceedings - K. V. Rozhdestvenskii 1Stephan Aubin
In 2001 Euroavia Toulouse organized a symposium on ground effect. We invited most of the Russian and German actors, and some experts from Holland, UK or France for a week of science around the subject of ekranoplans / flying boats. This was dedicated to students. A book was issued... and now that all copies have been sold for a while I am sharing this on LinkedIn for everyone.
Enjoy.
Stéphan AUBIN
Naca 2415 finding lift coefficient using cfd, theoretical and javafoileSAT Journals
Abstract In this paper we have studied the experimental characteristic graph of NACA 2415.The experimental graphs were taken from the book, “Theory of wing section” by IRA H. ABBOTT. We used these graphs for the validation of our results. Then we use CFD to simulate the experimental flow conditions and check the results and compare them with the experimental results. We meshed the airfoil in ICEM CFD so that the meshing is very precise. We then calculate the NACA 2415 airfoil’s lift at different angle of attack theoretically and using CFD analysis and compare them with the experimental values. We find the errors between experimental and CFD values as well as experimental and theoretical values. We used another simulation software called Javafoil and used it for comparison. Keywords: Experimental, CFD, Theoretical, Javafoil
This document presents a mathematical model for determining the minimum overtaking sight distance (OSDm) required for an ascending vehicle to safely pass another slower vehicle on a single lane highway with an incline. It defines sight distance, stopping sight distance, perception-reaction time and derives equations to calculate the reaction distance (d1), overtaking distance (d2), vehicle travel distance during overtaking (d3), and total minimum OSDm based on vehicle characteristics, road geometry, and coefficients of friction. The safe overtaking zone is defined as 3 times the minimum OSDm. The model accounts for effects of slope angle and aims to satisfy laws of mechanics for overtaking maneuvers on inclined two-way single lane highways.
Optimisation of the design of uav wing j.alexander, Prakash, BSM Augustinesathyabama
The document discusses the optimization of the design of UAV wings. It analyzes two types of rectangular wings using aerodynamic and structural design methods. Aerodynamic analysis using vortex lattice modeling found lift coefficients for the wings. Structural analysis using CATIA found that using composite materials instead of isotropic materials reduced mass by 34%. The optimum design of each wing maximized strength while minimizing mass and displacement.
Optimisation of the design of uav wing j.alexandersathyabama
The document discusses the optimization of the design of unmanned aerial vehicle (UAV) wings. It analyzes two types of rectangular wings using vortex lattice CFD software to determine aerodynamic loads and CATIA V5 software for structural analysis. When composite materials are used instead of isotropic materials, a 34% mass reduction is achieved. The optimum design is determined for each wing based on minimum mass, stress, and displacement.
This document summarizes the design of an optimal feedback control system for the final landing phase of an aircraft. It describes modeling the aircraft dynamics using a linearized transfer function relating elevator deflection and pitch rate. The design uses the parametric expansion method of optimization theory to synthesize time-varying feedback controls by minimizing an error index formulated from performance requirements. Several candidate control systems are compared by simulating aircraft landing trajectories.
This article considers different approaches for autopilot controller gain values adjustment. The correct autopilot
performance is tested using modeling methods. A variant of land-based autopilot is considered. Examined are
scenarios of UAV airplanes in level flight. The latter are applicable to tasks such as remote sensing, controlled
area surveillance, etc.
Automata Theory Models and Algorithms for Controlling an Aircraft Group in Av...IRJET Journal
This document discusses models and algorithms for controlling aircraft during landing when their positions are unknown due to external factors like weather. It proposes using finite state automata and generalized synchronization methods to model the aircraft system and develop dispatcher instructions to guide the aircraft safely. The problem is formalized and modeled as a finite state machine. Algorithms are described to find synchronizing sequences of commands to move the aircraft system to a safe configuration regardless of their initial positions. Linear finite state machine models are considered, which allows solving the problem using linear algebra methods to obtain short synchronizing sequences. This approach aims to help dispatchers efficiently guide aircraft groups during adverse conditions.
Analysis Of Owl-Like Airfoil Aerodynamics At Low Reynolds Number FlowKelly Lipiec
The document analyzes the aerodynamic characteristics of an owl-like airfoil at a low Reynolds number of 23,000 using computational fluid dynamics simulations. It finds that the owl-like airfoil achieves higher lift coefficients and lift-to-drag ratios than the Ishii airfoil, which was designed for high performance at low Reynolds numbers. The owl-like airfoil's round leading edge, flat upper surface, and deeply concaved lower surface contribute to lift enhancement through mechanisms like a suction peak and laminar separation bubble near the leading edge. However, the owl-like airfoil does not achieve its minimum drag coefficient at zero lift, unlike the Ishii airfoil. The document aims to provide insights that can
This document discusses methods for estimating aerodynamic properties of aircraft parts and surfaces needed to determine stability and control characteristics. These include estimating lift curve slope, zero-lift angle of attack, pitch moment, and downwash parameter for wings, horizontal tails, and vertical tails through relationships involving airfoil properties, geometry, and flow characteristics. Semi-empirical equations are presented to calculate these properties for straight tapered wings and tails using parameters like aspect ratio, taper ratio, sweep, and position.
A Statistical Computer Experiments Approach To Airline Fleet AssignmentGina Rizzo
- The document describes a statistical computer experiments approach to solving the airline fleet assignment problem using a two-stage stochastic programming framework.
- In the first stage, crew-compatible aircraft are assigned to flights. In the second stage, individual aircraft are assigned within families based on demand scenarios.
- A Latin hypercube design is used to generate initial crew-compatible allocations for the first stage. For each allocation and demand scenario, a deterministic fleet assignment model is solved. The expected revenue is estimated as the average over scenarios.
Researchers used strain gauges in a wind tunnel experiment to determine the drag coefficient of a 1:20 scale model Mercedes SEL 300 passenger car. Strain gauges measured bending moments on a cantilever beam as wind speeds up to 33 m/s were applied to the model. Drag coefficients between 0.37 and 0.19 were obtained, decreasing by about 50% as wind speed increased from 21.17 to 33 m/s. Analysis of measurement errors showed they decreased from around 8% to 3% over the same wind speed range. Flow visualization confirmed the formation of trailing vortices behind the model consistent with previous research. The strain gauge method was deemed practical and accurate for estimating automobile drag coefficients.
Strategic design of aircraft wings have evolved over time for maximum fuel efficiency. One of such ideas involves winglet which has been known
to reduce turbulence at the tip of the wings. This study intends to investigate the
differences in drag and lift forces generated at aeroplane wings with and without winglet at cruising speed using FEM. Simulations were performed in the
SST turbulence model of CFD and the results are compared to that of the experimental and theoretical models. The simulation showed that the lift increased
by 26.0% and the drag decreased by 74.6% for the winglet at cruising speed.
This document discusses an aeroelastic analysis of a stiffened composite wing structure conducted by researchers at Aeronautical Development Establishment. The researchers used the velocity-damping method to estimate the flutter speed and frequencies of an unmanned aerial vehicle's composite wing. Finite element modeling was conducted to determine the wing's natural frequencies. Input parameters were used in a MATLAB code developed based on the velocity-damping method equations to calculate the flutter speed. Results showed improved flutter speeds for the composite wing structure compared to an existing metallic wing design.
Abstract This paper presents the design and implementation of a quadcopter capable of payload delivery. A quadcopter is a unique unmanned aerial vehicle which has the capability of vertical take-off and landing. In this design, the quadcopter was controlled wirelessly from a ground control station using radio frequency. It was modeled mathematically considering its attitude and altitude, and a simulation carried out in MATLAB by designing a proportional Integral Derivative (PID) controller was applied to a mathematical model. The PID controller parameters were then applied to the real system. Finally, the output of the simulation and the prototype were compared both in the presence and absence of disturbances. The results showed that the quadcopter was stable and able to compensate for the external disturbances.
Abstract This paper presents the design and implementation of a quadcopter capable of payload delivery. A quadcopter is a unique unmanned aerial vehicle which has the capability of vertical take-off and landing. In this design, the quadcopter was controlled wirelessly from a ground control station using radio frequency. It was modeled mathematically considering its attitude and altitude, and a simulation carried out in MATLAB by designing a proportional Integral Derivative (PID) controller was applied to a mathematical model. The PID controller parameters were then applied to the real system. Finally, the output of the simulation and the prototype were compared both in the presence and absence of disturbances. The results showed that the quadcopter was stable and able to compensate for the external disturbances.
The International Journal of Engineering and Science (IJES)theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
This document discusses the fundamentals of aircraft aerodynamics. It introduces aerodynamics as the science of air motion and forces on aircraft. Aerodynamics is divided into sections based on speed and altitude ranges, including incompressible flows, subsonic, transonic, supersonic, and hypersonic aerodynamics. The main components of an aircraft are also introduced, including the wing, fuselage, tail unit, landing gear, and power plant. Coordinate systems used in aerodynamic analysis are defined.
10 fighter aircraft avionics - part iiiSolo Hermelin
This document provides a summary of fighter aircraft avionics across different generations of fighter jets. It discusses the avionics systems of third, fourth, 4.5 and fifth generation fighters. Specific avionics components covered include cockpit displays, communication systems, data entry/control, flight control, navigation, sensors and weapons systems. The document also discusses topics related to aircraft performance, flight instruments, propulsion and aerodynamics as they relate to fighter jet avionics.
Multi-objective and Multi-constrained UAV Path Plan Optimum Selection Based o...Angelo State University
This document discusses optimizing flight path planning for unmanned aerial vehicles (UAVs) using grey relational analysis. It establishes an optimal decision-making system and mathematical model for UAV flight paths that considers multiple objectives like minimizing costs and avoiding threats. Grey relational analysis is used to deal with relationships between various cost indicators and constraints to solve the optimization model. The model is applied to a problem involving 17 radar threats, 5 missile threats, 10 artillery threats, and 2 climate threats to obtain an optimal flight path.
М.Г.Гоман, А.В.Храмцовский (1998) - Использование методов непрерывного продол...Project KRIT
М.Г.Гоман, А.В.Храмцовский "Использование методов непрерывного продолжения решений и бифуркационного анализа для синтеза систем управления", Phil.Trans.R.Soc.Lond. A (1998) 356, 2277-2295
M.G.Goman and A.V.Khramtsovsky "Application of continuation and bifurcation methods to the design of control systems", Phil.Trans.R.Soc.Lond. A (1998) 356, 2277-2295
In this paper the continuation and bifurcation methods are applied to aircraft nonlinear control design problems. The search for the recovery control from spin regimes is based on the minimization of an energy-like scalar function constrained by the aircraft's equilibria conditions. The design of a global stability augmentation system for severe wing-rock motion is performed by using bifurcation diagrams for equilibrium and periodical modes. The nonlinear control law, which totally suppresses wing-rock motion, is derived, taking into account both local stability characteristics of aircraft equilibrium states and domains of attraction, along with the requirement that all other attractors be eliminated.
Brian Lane, assistant professor of physics at Jacksonville University: "Simulation of the Physics of Flight," published in the academic journal "The Physics Teacher"
This document describes an automatic safety door lock system for cars that uses infrared sensors and a hydraulic piston to prevent injuries caused by closing car doors. The system uses IR sensors placed along the door and outer panel connected to a microcontroller. When an object is detected between the closing door and outer panel, the sensors transmit a signal to the microcontroller which activates a relay driver to extend the hydraulic piston to stop the door from closing. The system aims to prevent the over 120,000 injuries that occur annually from unexpected car door closings.
Extrusion can be defined as the process of subjecting a material to compression so that it is forced to
flow through an opening of a die and takes the shape of the hole. Multi-hole extrusion is the process of
extruding the products through a die having more than one hole. Multi-hole extrusion increases the production
rate and reduces the cost of production. In this study the ram force has calculated experimentally for single hole
and multi-hole extrusion. The comparison of ram forces between the single hole and multi-hole extrusion
provides the inverse relation between the numbers of holes in a die and ram force. The experimental lengths of
the extruded products through the various holes of multi-hole die are different. It indicates that the flow pattern
is dependent on the material behavior. The micro-hardness test has done for the extruded products of lead
through multi-hole die. It is observed that the hardness of the extruded lead products from the central hole is
found to be more than that of the products extruded from other holes. The study suggests that multi-hole
extrusion can be used for obtaining the extruded products of lead with varying hardness. The micro-structure
study has done for the lead material before and after extrusion. It is observed that the size of grains of lead
material after extrusion is smaller than the original lead.
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Optimisation of the design of uav wing j.alexander, Prakash, BSM Augustinesathyabama
The document discusses the optimization of the design of UAV wings. It analyzes two types of rectangular wings using aerodynamic and structural design methods. Aerodynamic analysis using vortex lattice modeling found lift coefficients for the wings. Structural analysis using CATIA found that using composite materials instead of isotropic materials reduced mass by 34%. The optimum design of each wing maximized strength while minimizing mass and displacement.
Optimisation of the design of uav wing j.alexandersathyabama
The document discusses the optimization of the design of unmanned aerial vehicle (UAV) wings. It analyzes two types of rectangular wings using vortex lattice CFD software to determine aerodynamic loads and CATIA V5 software for structural analysis. When composite materials are used instead of isotropic materials, a 34% mass reduction is achieved. The optimum design is determined for each wing based on minimum mass, stress, and displacement.
This document summarizes the design of an optimal feedback control system for the final landing phase of an aircraft. It describes modeling the aircraft dynamics using a linearized transfer function relating elevator deflection and pitch rate. The design uses the parametric expansion method of optimization theory to synthesize time-varying feedback controls by minimizing an error index formulated from performance requirements. Several candidate control systems are compared by simulating aircraft landing trajectories.
This article considers different approaches for autopilot controller gain values adjustment. The correct autopilot
performance is tested using modeling methods. A variant of land-based autopilot is considered. Examined are
scenarios of UAV airplanes in level flight. The latter are applicable to tasks such as remote sensing, controlled
area surveillance, etc.
Automata Theory Models and Algorithms for Controlling an Aircraft Group in Av...IRJET Journal
This document discusses models and algorithms for controlling aircraft during landing when their positions are unknown due to external factors like weather. It proposes using finite state automata and generalized synchronization methods to model the aircraft system and develop dispatcher instructions to guide the aircraft safely. The problem is formalized and modeled as a finite state machine. Algorithms are described to find synchronizing sequences of commands to move the aircraft system to a safe configuration regardless of their initial positions. Linear finite state machine models are considered, which allows solving the problem using linear algebra methods to obtain short synchronizing sequences. This approach aims to help dispatchers efficiently guide aircraft groups during adverse conditions.
Analysis Of Owl-Like Airfoil Aerodynamics At Low Reynolds Number FlowKelly Lipiec
The document analyzes the aerodynamic characteristics of an owl-like airfoil at a low Reynolds number of 23,000 using computational fluid dynamics simulations. It finds that the owl-like airfoil achieves higher lift coefficients and lift-to-drag ratios than the Ishii airfoil, which was designed for high performance at low Reynolds numbers. The owl-like airfoil's round leading edge, flat upper surface, and deeply concaved lower surface contribute to lift enhancement through mechanisms like a suction peak and laminar separation bubble near the leading edge. However, the owl-like airfoil does not achieve its minimum drag coefficient at zero lift, unlike the Ishii airfoil. The document aims to provide insights that can
This document discusses methods for estimating aerodynamic properties of aircraft parts and surfaces needed to determine stability and control characteristics. These include estimating lift curve slope, zero-lift angle of attack, pitch moment, and downwash parameter for wings, horizontal tails, and vertical tails through relationships involving airfoil properties, geometry, and flow characteristics. Semi-empirical equations are presented to calculate these properties for straight tapered wings and tails using parameters like aspect ratio, taper ratio, sweep, and position.
A Statistical Computer Experiments Approach To Airline Fleet AssignmentGina Rizzo
- The document describes a statistical computer experiments approach to solving the airline fleet assignment problem using a two-stage stochastic programming framework.
- In the first stage, crew-compatible aircraft are assigned to flights. In the second stage, individual aircraft are assigned within families based on demand scenarios.
- A Latin hypercube design is used to generate initial crew-compatible allocations for the first stage. For each allocation and demand scenario, a deterministic fleet assignment model is solved. The expected revenue is estimated as the average over scenarios.
Researchers used strain gauges in a wind tunnel experiment to determine the drag coefficient of a 1:20 scale model Mercedes SEL 300 passenger car. Strain gauges measured bending moments on a cantilever beam as wind speeds up to 33 m/s were applied to the model. Drag coefficients between 0.37 and 0.19 were obtained, decreasing by about 50% as wind speed increased from 21.17 to 33 m/s. Analysis of measurement errors showed they decreased from around 8% to 3% over the same wind speed range. Flow visualization confirmed the formation of trailing vortices behind the model consistent with previous research. The strain gauge method was deemed practical and accurate for estimating automobile drag coefficients.
Strategic design of aircraft wings have evolved over time for maximum fuel efficiency. One of such ideas involves winglet which has been known
to reduce turbulence at the tip of the wings. This study intends to investigate the
differences in drag and lift forces generated at aeroplane wings with and without winglet at cruising speed using FEM. Simulations were performed in the
SST turbulence model of CFD and the results are compared to that of the experimental and theoretical models. The simulation showed that the lift increased
by 26.0% and the drag decreased by 74.6% for the winglet at cruising speed.
This document discusses an aeroelastic analysis of a stiffened composite wing structure conducted by researchers at Aeronautical Development Establishment. The researchers used the velocity-damping method to estimate the flutter speed and frequencies of an unmanned aerial vehicle's composite wing. Finite element modeling was conducted to determine the wing's natural frequencies. Input parameters were used in a MATLAB code developed based on the velocity-damping method equations to calculate the flutter speed. Results showed improved flutter speeds for the composite wing structure compared to an existing metallic wing design.
Abstract This paper presents the design and implementation of a quadcopter capable of payload delivery. A quadcopter is a unique unmanned aerial vehicle which has the capability of vertical take-off and landing. In this design, the quadcopter was controlled wirelessly from a ground control station using radio frequency. It was modeled mathematically considering its attitude and altitude, and a simulation carried out in MATLAB by designing a proportional Integral Derivative (PID) controller was applied to a mathematical model. The PID controller parameters were then applied to the real system. Finally, the output of the simulation and the prototype were compared both in the presence and absence of disturbances. The results showed that the quadcopter was stable and able to compensate for the external disturbances.
Abstract This paper presents the design and implementation of a quadcopter capable of payload delivery. A quadcopter is a unique unmanned aerial vehicle which has the capability of vertical take-off and landing. In this design, the quadcopter was controlled wirelessly from a ground control station using radio frequency. It was modeled mathematically considering its attitude and altitude, and a simulation carried out in MATLAB by designing a proportional Integral Derivative (PID) controller was applied to a mathematical model. The PID controller parameters were then applied to the real system. Finally, the output of the simulation and the prototype were compared both in the presence and absence of disturbances. The results showed that the quadcopter was stable and able to compensate for the external disturbances.
The International Journal of Engineering and Science (IJES)theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
This document discusses the fundamentals of aircraft aerodynamics. It introduces aerodynamics as the science of air motion and forces on aircraft. Aerodynamics is divided into sections based on speed and altitude ranges, including incompressible flows, subsonic, transonic, supersonic, and hypersonic aerodynamics. The main components of an aircraft are also introduced, including the wing, fuselage, tail unit, landing gear, and power plant. Coordinate systems used in aerodynamic analysis are defined.
10 fighter aircraft avionics - part iiiSolo Hermelin
This document provides a summary of fighter aircraft avionics across different generations of fighter jets. It discusses the avionics systems of third, fourth, 4.5 and fifth generation fighters. Specific avionics components covered include cockpit displays, communication systems, data entry/control, flight control, navigation, sensors and weapons systems. The document also discusses topics related to aircraft performance, flight instruments, propulsion and aerodynamics as they relate to fighter jet avionics.
Multi-objective and Multi-constrained UAV Path Plan Optimum Selection Based o...Angelo State University
This document discusses optimizing flight path planning for unmanned aerial vehicles (UAVs) using grey relational analysis. It establishes an optimal decision-making system and mathematical model for UAV flight paths that considers multiple objectives like minimizing costs and avoiding threats. Grey relational analysis is used to deal with relationships between various cost indicators and constraints to solve the optimization model. The model is applied to a problem involving 17 radar threats, 5 missile threats, 10 artillery threats, and 2 climate threats to obtain an optimal flight path.
М.Г.Гоман, А.В.Храмцовский (1998) - Использование методов непрерывного продол...Project KRIT
М.Г.Гоман, А.В.Храмцовский "Использование методов непрерывного продолжения решений и бифуркационного анализа для синтеза систем управления", Phil.Trans.R.Soc.Lond. A (1998) 356, 2277-2295
M.G.Goman and A.V.Khramtsovsky "Application of continuation and bifurcation methods to the design of control systems", Phil.Trans.R.Soc.Lond. A (1998) 356, 2277-2295
In this paper the continuation and bifurcation methods are applied to aircraft nonlinear control design problems. The search for the recovery control from spin regimes is based on the minimization of an energy-like scalar function constrained by the aircraft's equilibria conditions. The design of a global stability augmentation system for severe wing-rock motion is performed by using bifurcation diagrams for equilibrium and periodical modes. The nonlinear control law, which totally suppresses wing-rock motion, is derived, taking into account both local stability characteristics of aircraft equilibrium states and domains of attraction, along with the requirement that all other attractors be eliminated.
Brian Lane, assistant professor of physics at Jacksonville University: "Simulation of the Physics of Flight," published in the academic journal "The Physics Teacher"
This document describes an automatic safety door lock system for cars that uses infrared sensors and a hydraulic piston to prevent injuries caused by closing car doors. The system uses IR sensors placed along the door and outer panel connected to a microcontroller. When an object is detected between the closing door and outer panel, the sensors transmit a signal to the microcontroller which activates a relay driver to extend the hydraulic piston to stop the door from closing. The system aims to prevent the over 120,000 injuries that occur annually from unexpected car door closings.
Extrusion can be defined as the process of subjecting a material to compression so that it is forced to
flow through an opening of a die and takes the shape of the hole. Multi-hole extrusion is the process of
extruding the products through a die having more than one hole. Multi-hole extrusion increases the production
rate and reduces the cost of production. In this study the ram force has calculated experimentally for single hole
and multi-hole extrusion. The comparison of ram forces between the single hole and multi-hole extrusion
provides the inverse relation between the numbers of holes in a die and ram force. The experimental lengths of
the extruded products through the various holes of multi-hole die are different. It indicates that the flow pattern
is dependent on the material behavior. The micro-hardness test has done for the extruded products of lead
through multi-hole die. It is observed that the hardness of the extruded lead products from the central hole is
found to be more than that of the products extruded from other holes. The study suggests that multi-hole
extrusion can be used for obtaining the extruded products of lead with varying hardness. The micro-structure
study has done for the lead material before and after extrusion. It is observed that the size of grains of lead
material after extrusion is smaller than the original lead.
Analysis of Agile and Multi-Agent Based Process Scheduling Modelirjes
As an answer of long growing frustration of waterfall Software development life cycle concepts,
agile software development concept was evolved in 90’s. The most popular agile methodologies is the Extreme
Programming (XP). Most software companies nowadays aim to produce efficient, flexible and valuable
Software in short time period with minimal costs, and within unstable, changing environments. This complex
problem can be modeled as a multi-agent based system, where agents negotiate resources. Agents can be used to
represent projects and resources. Crucial for the multi-agent based system in project scheduling model, is the
availability of an effective algorithm for prioritizing and scheduling of task. To evaluate the models, simulations
were carried out with real life and several generated data sets. The developed model (Multi-agent based System)
provides an optimized and flexible agile process scheduling and reduces overheads in the software process as it
responds quickly to changing requirements without excessive work in project scheduling.
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International Refereed Journal of Engineering and Science (IRJES)
1. International Refereed Journal of Engineering and Science (IRJES)
ISSN (Online) 2319-183X, (Print) 2319-1821
Volume 2, Issue 5(May 2013), PP.0.1-08
www.irjes.com
www.irjes.com 1 | Page
Study on Free Flight Collision Risk in Free Flight Based on
Conflict
Zhang Zhao-ning1
, Zuo Jiang-li2
, Lu Fei1
(1. College of Air Traffic Management, Civil Aviation University of China, Tianjin 300300, China)
(2. Flight Test Center, Commercial Aircraft Corporation of China Ltd, Shanghai 200232,China)
Abstract: Free flight is one of the effective methods to solve airspace congestion, so in order to ensure flight in
free flight environment, the study of the collision risk is very important. Establish the collision risk model and
give the adjustment quantity of course or velocity based on the conflict detection and liberation. The feasibility
of collision risk model is verified through an example and the relationship between the risk of collision and the
different separation is analyzed. So the pilot can choose the appropriate flight plan according to the adjustment
quantity and the actual situation of the aircraft.
Key words:free flight; collision risk; course adjustment ;velocity adjustment
I. Introduction
The concept of free flight was proposed in 1965 [1-2]
by William. The implementation of the free flight can
not only save the flight time and fuel consumption, but also gain greater flight flow because of the full use of the
airspace. At the same time, the possibility of collision increases with the increased flight flow. To ensure flight
safety in free flight environment, the research on flight collision risk in free flight is particularly important.
Some fruit of free flight collision risk overseas has achieved. Some people like Rick Cassell, used the
method of accident tree by quantitative relationship between aircraft collision risk and safe separation, and they
gave the model of flight collision risk. Some scholars abroad also gave the model of airspace division sector
using and aircraft meeting. The model can well finish the use of airspace sector, airspace evaluation and analysis
of aircraft collision risk [3].
K.M. Feigh etc studied free flight deeply, and gave the conception of autonomous
Mediterranean Free Flight (AMFF, as - Mediterranean Free Flight), and they studied the flying state in high
density conditions especially, established and optimized the model of safety assessment based on AFMM [4]
.
At home, the research of collision risk in free flight, mainly concentrated in the technology of airspace
conflict detection and extrication. Zhang Zhao-ning, Cai Ming, Wang Li-li and Zhou Peng established the model
of collision risk assessment in free flight and evaluated security of flight separation[5-9]
. In 2012, Zhang
Zhao-ning, Sun Chang established the model of collision risk based on the liberation of conflict and analyzed
the relations between the conflict releasing Angle and collision risk [10].
Based on the research of conflict detection and release, the model of collision risk based on the different
solutions of conflict extrication, course adjustment and speed adjustment was established, using the principle of
relative motion. At the same time, the adjustment was given on the different solutions. So the pilot can choose
flight plan according to the actual situation.
II. The establishment of coordinate system
The airspace of aircraft flying is three-dimensional space. So the separation is restricted to the transverse,
longitudinal and lateral spacing. Using the coordinate of Descartes, the definition is as follows: the origin is one
2. Study on Free Flight Collision Risk in Free Flight Based on Conflict
www.irjes.com 2 | Page
point of the earth, the Z axis is vertical upward, the X axis is parallel to the horizontal and the Y axis is
determined according to the right-hand rule. In the spatial domain, N aircrafts are in flight-
, 1 2, , , ,i j nA A A A A ,
. Two aircrafts of them
,i jA A
are conflict detected and separation evaluated. At
same time, the state of all aircrafts can be obtained. If existing positions of two aircrafts overlap in space
position, there is the possibility of collision. Then the aircrafts need to be put out the conflict resolution to
ensure flight safety.
To describe the problem for the convenience, two aircrafts are projected in XOY and XOZ plane
respectively. The horizontal projective plane of aircrafts’ protection zone is defined as that the center is the
aircraft and the diameter of the area is S, as shown in figure 1. The vertical projective plane is the zone whose
diameter is H, as shown in figure 2.
According to the principle of relative motion, the speed of aircraft jA
relative to iA
can be expressed in hV
for
the horizontal plane and vV
for the vertical plane. If the protection zone of two aircrafts overlap, there is a
collision. The pilot can adjust the course and speed to avoid collision. It can be safe only when the protection
zone of aircraft jA
is in the front or rear of iA
.
Ai
Aj
Vi
V
j
Vh
Vh
X
Y
S1
Figure 1 motion vector diagram of aircraft in XOY plane
Ai
Aj
X
Z
S2
Vi’
Uj’
Uj’
Vi’
Vv
Figure 2 motion vector diagram of aircraft in XOZ plane
According to the principle of relative motion, the motion state is transformed to relative motion state: aircraft
3. Study on Free Flight Collision Risk in Free Flight Based on Conflict
www.irjes.com 3 | Page
iA do standard Brownian motion in original point and aircraft jA is flying with relative speed hV and vV .
1 and 2 are positioning errors in a horizontal plane and vertical plane respectively, which obey normal
distribution
2
1 1(0, ( ))N t and
2
2 2(0 ( ))N t, .
III. The establishment of collision risk model
2.1 The establishment of collision risk model basing on course adjustment
The pilot can change course to avoid collision. Assuming in the flight process, only one aircraft in two
aircrafts changes heading and the other one continues the original track flight. According to the common flight
rules, if flight collision happens in the flight process, we only change the speed in horizontal plane instead of
changing climbing and descending height of aircraft.
Figure 3 shows the course adjustment method to avoid conflict. The D is the initial distance between aircrafts in
a horizontal plane and the h is the vertical distance in vertical plane.
D
V1h after Heading
adjustment
θ1
θ2
θAi
Aj
V1水
β
Figure 3 diagram of course adjustment method to avoid flight conflict
From figure 3, it is known that in the process of course adjustment, it need to keep the aircraft iA course
unchanged and only aircraft jA course is adjusted. Define that the left-handed rotation is negative and the other
is positive. So the adjustment of heading is = - .
The distance in a horizontal plane between two aircrafts is as follows
1 1 2 1( ) cos ( ) / cos( )hX t D V t 1h
The distance in a vertical plane between two aircrafts is as follows:
2 ( ) + vX t h V t 1v
obeys the standard normal distribution,
2
(0, ( ))N t . The formula can be derived to:
4. Study on Free Flight Collision Risk in Free Flight Based on Conflict
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1 1 2 1
2
1 2 1 2 1 1 1 2 1
2 2
1 1 2 1 1 2 1
( ) cos ( ) / cos( )
cos / cos( )- / cos( )- (0 ) / cos( )
(( cos - ) / cos( ) / cos ( ))
hX t D V t
D V t N
N D V t
1h
1h
1h
,
,
2 2
2 2 2 2 2( ) + (0 )= ( )vX t h V t h V t N N h V t 1v 1v 1v, ,
Where 1 2 1( cos - ) / cos( )hu D V t 1h ,
2 2 2
1 2 1/ cos ( )h , vu h V t 1v ,
2 2
2v .
The probability density function of distance for Aircraft in a horizontal and vertical plane can be derived as
follows:
2
2
1
-
2 ( )1
( )
2 ( )
h
h
x u
t
X
h
f x e
t
( )
2
2
2
-
2 ( )1
( )
2 ( )
v
v
u
t
X
v
f y e
t
(y )
The probability of collision risk based on course adjustment in free flight is:
1 1 1( )= ( ) ( )h vP t P t P t
( )P t1h and ( )P t1v are the probability of collision risk based on course adjustment in a horizontal and vertical
plane. According to formula (5) and (6), ( )P t1h and ( )P t1v can be derived as:
2
21 1
1 1
( )
2
1
1
= ( )
2
h
h
x
S S
h uS S
h
P f x dx e dx
水
2
22 2
2 2
( )
2
1
1
= ( )
2
v
v
v
y
S S
v uS S
v
P f y dy e dy
1S and 2S are the minimum safety separations in the horizontal and vertical plane under free flight.
Every collision should be counted as two accidents. Considering in 107 flying hours, the probability CR of
collision risk based on course adjustment can be expressed as:
1
10
2 ( )
t
CR NP P t dt
NP is the number of aircrafts in each flight hour.
2.2 Establishment of collision risk model based on course adjustment
As shown in figure 4, when the protection zones of aircrafts overlap, the velocity of the aircrafts will be
adjusted. For the convenience of building model, it is assumed that only the velocity of aircraft jA is to be
adjusted.
5. Study on Free Flight Collision Risk in Free Flight Based on Conflict
www.irjes.com 5 | Page
D
V2h after velocity
adjustment
Φ1
Ai
Aj
V2水
β
Vj
Vi
Φ2
Φ
λ
V2h after velocity
adjustment
Figure 4 diagram of velocity adjustment method to avoid flight conflict
From figure 4, in the horizontal plane the relationship can be known:
sin(180 ) sin( )
ji
VV
'
sin(180 ) sin( )
ji
VV
The formula of velocity adjustment is as follows:
'
sin( ) sin( )
sin(180 ) sin(180 )
i i
j j j
V V
V V V
According to the collision avoidance mechanism, the distance formulas of velocity adjustment in the horizontal
and vertical plane respectively is:
'
1 1 2 1
2
1 2 1 2 1 1 1 2 1
2 2
1 1 2 1 1 2 1
( ) cos ( ) / cos( )
cos / cos( )- / cos( )- (0 ) / cos( )
(( cos - ) / cos( ) / cos ( ))
hX t D V t
D V t N
N D V t
2h
2h
1h
,
,
' 2 2
2 2 2 2 2 2( ) + ( ) (0 )= ( )vX t h V t X t h V t N N h V t 2v 2v 2v, ,
Where
'
1 2 1( cos - ) / cos( )hu D V t 2h ,
2 2 2
1 2 1/ cos ( )h ,
'
vu h V t 2v ,
2 2
2 垂 .
2 ( )P t is the collision probability based on velocity adjustment. ( )P t2h and ( )P t2v are the collision
probability in horizontal and vertical plane respectively. So the collision probability can be expressed as:
2 ( )= ( ) ( )P t P t P t2h 2v
6. Study on Free Flight Collision Risk in Free Flight Based on Conflict
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The overlapping probability in horizontal and vertical plane are following respectively:
' 2
21 1
'
1 1
( )
21
= ( )
2
h
h
h
x
S S
uS S
h
P f x dx e dx
2h
' 2
22 2
'
2 2
( )
21
= ( )
2
v
v
v
y
S S
uS S
v
P f y dy e dy
2v
At the same time, the collision probability based on velocity adjustment is:
2
20
2 ( )
t
CR NP P t dt
IV. Analysis example
3.1 Determination of parameters
At present, the free flight has not yet been put into effect, so the relevant parameters can't be accurately put
forward. Therefore, the example of this model draws on the experiences of the data of non-free flight. The
relevant parameter is shown in table 1.
Assume that in free flight, aircraft is flying along a straight line in a period of time. The cruising speed of
aircraft iA and jA is the same, on the cruising speed of Boeing 747-400. Horizontal speed is 485 knots and
vertical speed is 0.05 knots. While the speed angle in the horizontal plane is sixty degrees, horizontal distance D
is twenty nautical mile , and vertical distance is 0.15 nautical mile.
For the course adjustment, the amount of heading is 18°and the collision risk is 2.35 x 10-9
.For the
velocity adjustment, it is appropriate to change 160 knots in velocity and the collision risk is 2.57 x 10-9
. From
results above, in this situation, course adjustment is in the range that the performance of the aircraft allows with
the same probability collision. If the speed adjustment changes a lot, this model is not appropriate. Usually, the
method of avoidance mechanism is to change course, the calculation results is also according with the actual
situation.
3.2 The influence of different separations to collision risk
Figure 5 shows the influence of different initial separations to flight collision risk based on the course
adjustment. With the increase of the initial interval, collision risk reduces, which is consistent to the present air
traffic situation.
7. Study on Free Flight Collision Risk in Free Flight Based on Conflict
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Figure 5 diagram of relationship between initial separation and collision risk
V. Conclusion
The different collision risk models are established innovatively on the bases of different schemes to relief
8. Study on Free Flight Collision Risk in Free Flight Based on Conflict
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from conflict, adjust course and velocity, according to the collision avoidance mechanism. The model considers
influence of the positioning error to collision risk. And the numerical results show that the model is feasible. At
the same time, the results also show that the course adjustment method for collision avoidance is the most
reasonable, which fits to the actual situation. At last, the relationship between the separation and collision risk is
analyzed and the different collision risk is provided on the different separation. So, the pilot can choose
appropriate way to ensure flight safety according to the actual situation of aircraft, which makes the flight more
flexible.
VI. Acknowledgements
The authors were supported by the National Natural Science Foundation of China (No.71171190) and Civil
Aviation Science and Technology Foundation (No. MHRD201018).
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