Quadrotor Helicopter

Question: Describe about the Quadrotor Helicopter? Answer: Introduction A quadcopter or a quadrotor helicopter is a helicopter with multiple rotors, which uses four rotors or motors to perform the upliftment operation. The four rotors attached to it are used to propel the quadcopter. Quadcopter has two fixed pitched propellers, which are identical: two anticlockwise and two clockwise. They are used to control torque and lift by varying the RPM of the rotors. In this project, a quadcopter has been designed, and its hardware has been implemented. The report describes the designing and development part in details. The materials used has also been discussed in the report. The quadcopter so developed, is a working model and take a successful flight. Quadcopter finds a variety of applications in various fields. Some of them are: Research Uses: Where it is used to study the aerodynamics and physics behind it. Military Use: It is used in the military for surveillance and reconnaissance. They are commonly referred to as drones here. They can perform great tasks as they are unmanned. Commercial Use: Their commercial use is on a boom in todays world. They are used for HD photography, for video coverage of events, delivery system to remote locations etc. Many more uses are planned in recent future. Implementation Main Design and Working The rotors of the quadcopter are used to produce thrust. Torque is also produced by them, which is about the centre of rotation. The drag force produced is opposite to the direction of light of the quadcopter. Fig. Torque on each motor on the quadcopter If all rotors are spinning at the same angular velocity, with motors 1 and 3 rotating clockwise and rotors 2 and 4 counter clockwise, the net aerodynamic torque, and hence the angular acceleration about the yaw axis, is exactly zero, which implies that the yaw stabilizing rotor of conventional helicopters is not needed. Yaw is induced by mismatching the balance in aerodynamic torques (i.e., by offsetting the cumulative thrust commands between the counter-rotating blade pairs). Materials Used The main materials needed for building a quadcopter are: propellers, frame, and motors/rotors. In our project, we have used a hybrid combination of plastic and wooden frame. The frame have been crafted out from a sheet of light weight wood, and have been designed according to the need. The propellers are made of plastic, and are of fixed pitch. They are durable and good for the project. Very high RPM brushless DC motors have been used in the project as rotors. The battery is also a very important component needed in the project. The battery used in our project is a Li-Po battery, which is rechargeable. The image of all the components and their assembly has been attached in the Appendix of this project. Result The quadcopter has been designed and implemented on the hardware successfully. The quadcopter takes the flight like it should, and can be manually controlled. It has a microcontroller embedded in it, and it can be programmed to work on its own. The battery once charged can be used to fly the quadcopter for about 15 minutes. Better battery can be used to make it fly for longer durations. The flight dynamics and flying can be controlled by controlling the rotors, as described above. Evaluation A very light weight material has to be used for the quadcopter frame. We have used a combination of plastic and wood. But instead, if we used the whole body made of light weight plastic, it would have been lighter. The se of carbon fibre material is also recommended. It is a very light material, and hence, perfect for the small quadcopter project. It is also very sturdy and can be used to carry weights with the quadcopter as payload. These weight can be camera or GPS devices, or such instruments, if we wish to extend the project further and make it more useable. The use of better battery is also recommended. Through, the battery should be always Lithium ion polymer battery, as it can provide a steady current for a longer duration of time. If the battery has more mAh rating, it could provide current for longer duration, and hence, the quadcopter could take longer duration flights. Also, if we wish to extend the project by integrating other peripherals like camera or GPS device to the quadcopter, a better battery would be needed to power such a device too. The quadcopter can be made wireless by using and integrating a wireless device with it, like Wi-Fi device or a Bluetooth device. Most popular device used with quadcopter are ZeegBee, which are should distance wireless devices. They can be easily integrated and programmed with our project. The project doesnt require any special maintenance. Though, the battery, if not taken proper care of, can become useless after some time. So, it should be properly turned off and disconnect after every use. The charging and discharging cycle should also be kept in mind. Conclusion The quadcopter has become a very important field of research and development. It has been expected to take over many important activities like delivery system, and extensive use in defence. In this project, we have successfully developed and implemented the hardware of a quadcopter. The functionalities of the developed project is: it can take a flight, change direction, change altitude, rotate.