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![• The key control inputs for a fixed-wing air vehicle are as follows:
• (a) Throttle: it controls the engine speed and, therefore, the movement of the propeller [19].
Throttle handles not only the forward speed of the aircraft but also, more importantly, the rate of
rising and fall, since various airspeeds generate various extents of lift [20]. You can lift the aircraft a
little without affecting the speed just by increasing throttle. On the other hand, reducing the throttle
will make the airplane descend before the speed decreases
• (b) Blade pitch: the hinged part of the horizontal tail controls the pitch of the aircraft as shown
in Figure 3. They are at the back of the aircraft and are some of the most significant control inputs.
Blade pitch controls the pitch attitude of the aircraft, i.e., whether the aircraft’s nose moves up or
down [21]. The nose of the aircraft points up when the blade pitch is up and it points down when
the blade pitch is down.
• (c) Thrust vectors: thrust vectors manage the turning of the aircraft [22]. They function as
opposed to each other which means that when one of them goes upwards, the other one goes
downwards. Thrust vectors function by varying the lift over the wing. As a thrust vector goes up, it
disturbs the flow of air over that wing and so the lift is decreased a little. The thrust vector on the
other wing goes down and the lift increases a bit. Consequently, the aircraft tilts and, therefore,
turns to the side that's undergoing decreased lift.irplane descend before the speed decreases.](https://image.slidesharecdn.com/droneswithfixedwingsanddesignconsiderations-250619061404-143efec9/75/Drones-with-fixed-wings-and-design-considerations-pptx-7-2048.jpg)
Drones with fixed wings and design considerations.pptx
- 1.
- 2. INTRODUCTION : Intoday’s world, the UAV’s, or Remotely Piloted Vehicles plays a very important role in completing Various tasks like goods distribution, commercial monitoring surveillance for military applications, object tracking, quality aerial imaging etc., that are not possible by the manned flight. The UAVs are controlled remotely which only requires a trained operator. Moreover, these minimizes the danger to the person controlling it and also provides flexibility for quick inspection in the critical regions. The most important advantage for which these flying aircrafts are used are the safety of the pilot who does not accompany the vehicle and the low cost of the production. The wings are the main lifting component in the fixed wing design. A critical aerodynamics study is done to study the various airfoil shapes which can give appropriate lift and thrust as per the design and mission requirements. The design changes in the airfoil design can result in better L/D. Hence, the UAV can generate more lift with a minimal drag. The fixed wing design require less power and thrust loading when compared with the multi copter. The fixed-wing UAVs are very advanced machines which are exclusively significant in terms of aerodynamics performance, maneuvering, structure load carrying capabilities and performing stealth, military and commercial operations. Various flight tests and experimental analysis have shown that the UAV’s offer remarkable performance with higher range and endurance when compared to the manned systems.
- 3. FIXED WINGUAV PARTS :
- 4. There arefour main forces operating on an aircraft. They are : 1. Lift L, which is perpendicular to the flight path direction. 2. Drag D, which is parallel to the flight path direction. 3. Weight W, which acts vertically toward the center of the earth (and hence is inclined at angle θ with respect to the lift direction). 4. Thrust T, which in general is inclined at the angle αT with respect to the flight path direction. During steady flight these forces are in equilibrium, which means thrust counteracts drag and lift counteracts gravity. T/W=D/L (Level Flight Condition)
- 5. Design Cycle forFixed Wing UAV
- 6. Dynamics of theFixed wing UAV An aircraft is able to spin around three axes from the center of gravity of the plane. The position control of the gyrocopter is typically transformed into the angular control, namely, roll, pitch, and yaw (φ, θ, ψ) presents the aircraft with the reference coordinate systems. To describe the movements of the gyroplane, two reference systems are required: the earth frame and the body frame. The movement of the aircraft is calculated by geographical maps; that is why this study uses an Earth frame. The starting point of this system attaches to the surface of the Earth, and the axes (Xe, Ye, and Ze) are pointed to corresponding coordinates. The body frame system (Xb, Yb, and Zb) is the fixed body system that is positioned in the gravity center of the gyrocopter where gamma1 and gamma2 represent the tilt angles of the servo motors. Figure shows the model of the proposed aircraft with two propellers and a rotor.
- 7. • The keycontrol inputs for a fixed-wing air vehicle are as follows: • (a) Throttle: it controls the engine speed and, therefore, the movement of the propeller [19]. Throttle handles not only the forward speed of the aircraft but also, more importantly, the rate of rising and fall, since various airspeeds generate various extents of lift [20]. You can lift the aircraft a little without affecting the speed just by increasing throttle. On the other hand, reducing the throttle will make the airplane descend before the speed decreases • (b) Blade pitch: the hinged part of the horizontal tail controls the pitch of the aircraft as shown in Figure 3. They are at the back of the aircraft and are some of the most significant control inputs. Blade pitch controls the pitch attitude of the aircraft, i.e., whether the aircraft’s nose moves up or down [21]. The nose of the aircraft points up when the blade pitch is up and it points down when the blade pitch is down. • (c) Thrust vectors: thrust vectors manage the turning of the aircraft [22]. They function as opposed to each other which means that when one of them goes upwards, the other one goes downwards. Thrust vectors function by varying the lift over the wing. As a thrust vector goes up, it disturbs the flow of air over that wing and so the lift is decreased a little. The thrust vector on the other wing goes down and the lift increases a bit. Consequently, the aircraft tilts and, therefore, turns to the side that's undergoing decreased lift.irplane descend before the speed decreases.
- 8. Inflow Velocity ofthe Rotor: • The inflow velocity V is divided into two main components as shown in Figure and given as follows: • Vbreaks down into----- V cos alphaR,V sin alphaR
- 9. • Taking ablade at a radius r as an example, the tangential inflow velocity ut and perpendicular inflow velocity up of the blade can be obtained by combining the rotor speed Ω and the blade angle as shown in Figure 4(b) and given as follows: • where represents the speed of rotating blades and is the induced speed of the blade. • 3.2. Blade Force Analysis • The aerodynamic force acting on the profile is arbitrarily intercepted at a certain radius of the blade as shown in Figure. • u(t)=V cos alphaR sin chyR • u(p)= V sin alphaR+ v +v beta
- 10. • SPEED CONTROL: •The main factors affecting the speed of the rotor aircraft are the resistance of the rotor blade and the forward thrust of the engine. The closed-loop control of the speed is implemented by manipulating the relative pitch angle of the rotor blade and the engine thrust. The best control effect cannot be achieved by operating alone. Therefore, considering the influence of blade resistance, it is essential to coordinate and change the pitch angle of the rotor when controlling the speed. • ALTITUDE CONTROL: • Due to the rotation characteristics of the unmanned rotor aircraft, the pull force of the rotor blade is related to the angle of attack and the inflow velocity, so increasing the angle of attack or the speed of the rotor aircraft can increase the lift of the rotor aircraft and increase the altitude.
- 11. • Figure 17presents the overall framework of the system. As is apparent in the figure, the two main parts of the system are a ground part and an airborne part. The ground part mainly consists of the ground control station, antenna, and display computer. The airborne part has a radio, antenna, sensors, and a central processing unit that controls the whole process.
- 12. Simulation Test • Thesimulation test of the proposed aircraft is essential to prove the relevant control strategy and flight control system designs are able to control the maneuvering of the aircraft. On the basis of the whole aircraft flight control system, a simulation computer is added to form a semiphysical simulation platform. Figure 20 presents the simulation platform.
- 13. • Conceptual Design:It is the first stage of the aircraft design. Here, the rough sketches and the design geometries are sketch on a paper. Different layout is worked on so that the best design can be chosen for further calculation. The designers work to obtain a suitable aircraft configuration that meets the market demand and also fulfil the mission requirement. Here, consideration is laid on the aerodynamics, stability, structural configuration, performance, weight, and the control systems. However, the initial design begins with the selection of wings, fuselage design, and the aircraft’s engine size. • Preliminary Design: The second stage of the design process is the preliminary design. This design process involves the calculation parts which proves that the selected design meets the requirements. The calculations are performed on aerodynamics, flight mechanics, flight dynamics, structural analysis. Further, the use of the software’s like CATIA for CAD design, ANSYS for structural analysis, MATLAB for weight estimation is also used to verify the analytical calculations. The calculations and the iterations are performed so that the concept can be transformed to reality and at a reasonable cost.
- 14. • Detail Design: •The detail design is the final design stage where the concept is designed using a CAD software. Since the calculations in the preliminary design stage is fixed, so the next stage is to fix the final design. The drafting is done based on the 3rd angle projection and the 1st angle projection. This is a highly complex and critical stage of the process. After the CAD design and the drafting, the component is prepared for the fabrication of the parts. The fabrication can be done in two ways: • Directly using the drafting sheets for fabrication and assembly of parts • Using the prototype model in order to study the critical design areas and then proceed with fabrication accordingly.The critical components that are designed are airfoil, wing, fuselage, empennage, propulsion system, landing gear, control surfaces, etc. • Flight Testing: • In this stage, the fabricated component is tested whether it is meeting the mission requirements or not. The flight testing is a lengthy and expensive process because it must be ensured that the fabricated structure satisfies all the tests and produces good results
- 15. SIGNIFICANCE: More excellent stability: Fixed wing UAVs are similar to conventional aircraft in design. They are often more stable with their underside winds than their counterparts. Power loss recovery : Fixed wing UAVs can recover from power failure when other types of drones would shut down completely. While other drones would fall, fixed- wings can continue to glide and land without power. Longer flight time : Their aerodynamic design allows fixed wings to glide with wind currents. While multirotor drones or quadcopters have a 30 minute average flight time, fixed - wing models can fly as long as 90 minutes. Higher altitude : Using lift like an airplane gives fixed wing drones long range. As a result, they can reach height as high as 110 metres or more, depending on the model. Minimal noise : Another advantage fixed wing models have is the lack of noise compared to multirotor models. They are quieter and less conspicuous, making them better for large scale surveillance.
- 16. Recent Advancesin Unmanned Aerial Vehicle : In recent decades, aerial robots especially small UAVs and drones have witnessed tremendous improvements in terms of their structure, working methodology, flyng featres and navigation control. UAVs are highly utilized in a wide range of services such as photograohy, path planning, search and rescue, inspection of power lines and civil constructions etc. Unmanned Aerial Vehicle or pilotless aircaraft operates with advanced components including a physical model, Ground control station (GCS), modern sensors and a platform for ease of communication between them. In the past, UAVs are used for civilian and military operations such as rescue and search, climate monitoring, surveillance, weather forecasting and mapping. Since the evolution of modern technology and innovations in internet, UAVs has completely changed. Nowadays, UAVs are also used in emergency evacuations during natural disasters like storms, floods and bush fires, etc.
- 17. Electrical Components: 1. Brushless Motor : The brushless motor is the power plant of the fixed wing UAV. The brushless motor used is of the G-Power series and runs at 1500 KV. 2. Lipo Battery : The Lithium Polymer battery is the power hub for the propulsion system and other electrical components. 3. Electronic Speed Controller : It regulates the speed of the electric motor and can be controlled by the transmitter by the user. It also converts the battery voltage down to 5V, which is required by the transmitter to work. This property is known as the Battery Elimination Circuit (BEC).
- 18. 4. Transmitter : Thetransmitter is the remote control of the fixed wing UAV. The transmitter sends the signal to the receiver which controls the servomechanisms to move the control surfaces and turn on and off the camera. 5. Receiver : It is an electronic device which uses the radio waves and extract the useful information such as the movement of the control surfaces, propulsion system and the camera function. It receives the signals from the transmitters and send signals to the servo motors for control surfaces and the ESC for the motor control. 6. Servo Motors : The servo motors are used as the rotary actuator in the fixed wing UAV to move the control surfaces i.e, controlling the movement of ailerons,elevator and rudder.
- 19. APPLICATIONS : Remote-controlled (RC) racing : This sport allows participants to control racing drones while wearing a head-mounted display to see in the first person. Military operations : Long-range and high altitude surveillance and area mapping make fixed-wing models a mainstay in military operations. Overseas freight/cargo delivery : Whether lightweight packages between tankers or nearby countries, fixed-wings can easily carry and drop off payloads. Crop spraying : A fixed wing drone can easily be used in agriculture to optimize crop spraying over several hectares. Medical supplies delivery : Similar to overseas cargo delivery, fixed wing drones can drop medical supplies in hard-to-reach areas. Wildfire tracking and mapping : Like other drones, fixed-wing models can be equipped with real-time imaging, allowing firefighters to respond quickly.
- 20. Timeline Slide Feb 10 Feb22 Mar 4 Mar 17 Apr 2 Feb 10 Feb 22 Mar 4 Mar 17 Apr 2 Completing the basic structure and working of fixed wing UAV Detailed collection of information about design Complete information about battery management system Completion of matlab program for control management of fixed wing drone Completion of total project