Quadcopter Drones Aims To Be the Best Future Aircraft Designs
WHAT IS A QUADCOPTER?
A new technology that has become a dominant design in the construction of toy-sized drones, a quadcopter is a multirotor helicopter which gave it the name “quadrotor helicopter”.
It is a drone helicopter using sets of electric motors positioned at rectangular, hexagonal, or octagonal positions to lift and propel the drone. The electric motors serve as the main engine source for the drone and are being powered by rechargeable LiPO4 or Nickel Batteries.
The quadrotor helicopter or quadcopter has a unique design when compared to the conventional helicopter which has only one moving blade at the top and a small blade at the tail side in some designs.
The quadcopters had been classified under the aircraft category as the “rotorcraft” due to their lift action which is made possible through the sets of rotors positioned upward at either side of the drone.
FEATURES OF QUADCOPTERS
Quadcopters at their basic design use four arms equipped with exact sets of rotors which is where the name “Quad” meaning “Four” came from. However, advancement has revealed similar designs with six and eight rotors which were classified as quadcopters.
In the basic design, the quadcopter is a flying vehicle or drone with four arms extensions having a uniform electric motor fixed at each arm with a propeller of the same size attached to each of the motors.
In the controlling section, quadcopters usually have a four-channel controller that sends commands to the drone to affect its throttle, yaw, pitch, and roll.
The controller enables the operator to control any drift in the position of the drone while taking a flight. The wireless connection frequency of 2.4 GHz had been the most common frequency used in drones.
The drone’s propellers are of two sets, one set rotates in the clockwise direction while the other set rotates in the anti-clockwise direction.
The main body of the drone can be located at the center which usually has a camera attached to it and the same unit bears the battery used in powering the electric motors.
The quadcopter uses rotors that are able to vary the pitch of their blades dynamically as they move around the rotor hub.
In the designing of quadcopters, the motor capacity and RPM are paramount for the success of the design, other factors include; the motor spacing calculations.
The total weight of the quadcopter in regard to the rotors’ propelling thrust needed for the lifting and control, the accuracy of the motors power rating and uniform RPMs of each motor, etc. when these factors are in their proper places the quadcopter can fly and function successfully after production.
HOW THEY OPERATE (WORKING PRINCIPLE)
The quadcopter makes its successful flight through the actions of the rotors, two sets of rotors are in it, and one set is rotors at their diagonal positional and the same with the other set.
Two of the rotors in a set turn clockwise, while the other two in the other set turn anti-clockwise.
Being an aerodynamically unstable vehicle, the speed of each set of rotors creates the change in direction of the drone either left or right, backward or forward, while the lift action works when the whole rotors are in uniform speed to propel the body upward.
While in operation, the controller sends information to the motors through the wireless electronic speed control system and the information that can be sent to the motors are the thrust, revolution per minute(RPM), direction of flight signal, etc. combining IMU, Gyro and GPS data for the signal and the drone control.
A defect in any of the motors will alter the flight directions and smooth hovering in certain directions or show obvious difficulty while sending a signal for the flight control.
During the flight, each rotor will produce both a thrust and torque about its center of rotation and create a drag force that will be opposite to the drone’s direction of flight.
So if all the rotors are spinning at the same angular speed having the rotor 1 & 4 spinning in a clockwise direction and the rotors 2 & 3 spinning in the anti-clockwise direction, the total aerodynamic torque will be balanced which will make the angular acceleration of the drone about the yaw axis to be Zero, making the vehicle to be in a stable state.
The principle explained above makes the drone operate without a tail rotor as can be found in conventional helicopters since the tail rotor’s function is to balance the aerodynamic torque in the helicopters.
SAFETY FEATURES OF QUADCOPTER DRONE
The design and working technics of quadcopters are quite different from those of airplanes and helicopters. The presence of multirotor at a various positions outside the main body of the drone provides a level of security to the device.
While the airplane will require the wings for lifting, control, and landing, the quadcopter requires only the rotors for the mentioned actions.
Though helicopter and quadcopter are of the same category of rotor thrust aircraft, the helicopter offers a higher risk than the quadcopter because of the absence of an inbuilt parachute, and lack of rotor support in the case of technical failure.
Evidence has shown that any serious technical malfunctioning in one of the motors may not cause the drone to clash rather, there will a drastic reduction of power for lifting and hovering flights while the drone may become unable to fly in certain directions.
While in a severe condition the drone may smoothly reveal the defect by not responding properly to the wireless control.
The space created at the drone body is enough to be used in improving safety such as installing a parachute in the case of big-sized passenger drones like the EHANG 184 model.
The persistent problems of vertical flight were addressed through the quadcopters’ design thereby providing more stable and windstorm resistant flight which may not be found in conventional helicopters and airplanes. The directional change, vertical flight, and terrain maneuver can be seen in quadcopters.
DIFFERENCE BETWEEN HELICOPTERS AND AIRPLANES
The major difference between the two is that the helicopter is a rotor-propelled aircraft while the airplane uses a combination of rotors and wings for propelling. The helicopter uses more power for its flight than the airplane and moves slower than an airplane but it has the advantage of complete flight control and the ability to land and take off on any solid ground surface.
The helicopter is designed to rely wholly on the engine rotors for all of its actions during the flight which includes taking off from the ground, thereby making the helicopter engine have a larger engine than an airplane of the same size.
It has greater control against windstorms than an airplane and lifts a heavier load than an airplane of similar size.
However, the airplane can have greater speed during the flight but its movement is usually in a forward direction while the helicopter can hover in a place while in the air and move into remote places in a controlled manner.
Based on the above differences, helicopters are good for surveillance and military actions while airplanes are good mainly for air transportation, at the advanced level the two giant air vehicles are used for the two purposes mentioned above respectively.
HOW FUTURE AIRCRAFT MAY LOOK
The new look of the helicopter model called the quadcopter which had been used to make different sizes of drones and used to build the successfully produced passenger driverless flying vehicle called EHANG 184 made by a Chinese firm, has brought a new idea towards the design of the future aircraft.
Quadcopter’s design perfection which has led to the present-day stability in quadcopter drones will definitely silence the initial design for helicopters that use only one or two blades.
The following designs; The Bell Boeing Quad Tiltrotor, the AeroQuad and Arducopter, Parrot Ar Drone, and Nixie drone, etc. found in the drone model may soon become the model of new commercial passenger aircraft as the EHANG 184 had already shown.
It is believed that soon helicopter manufacturing firms may start adopting the quadcopter design for the same purpose helicopters were meant for in other to stay up to the upcoming marketing competition which may cause the initial aircraft designs to have low demand.
