Multirotor Drone : Working, Components, Types, Differences & Its Applications

At present, drones have become very popular in many fields like mapping, racing, logistics, surveys, and many more. It is an unmanned aerial vehicle or unmanned aircraft system, which is a flying robot that can fly autonomously or controlled remotely. Thus, these drones are embedded with software-controlled flight that works in combination with a global positioning system and sensors. There are different types of drones available in the market with different sizes and used for different purposes like multi-rotor, single-rotor, fixed wiring, and fixed-wing hybrid VTOL. However, multi-rotor drones play a key role due to their widespread usage. This article elaborates on a multirotor drone, their working, and their applications.

What is a rotor Drone?

A multi-rotor drone is an unmanned aerial vehicle or a multi-copter that utilizes various rotors with fixed-pitch revolving blades to produce lift and propulsion by allowing vertical takeoff, hovering, and landing capabilities. So, the rotor angle can be fixed and not changeable, similar to a helicopter. By modifying the relative speed among different rotors, the propulsion torque force can be modified to control the aircraft’s trajectory.

The multi-rotor is fairly simple and constant, and the multi-rotor aircraft’s appearance  is much smaller as compared to the aircraft. Thus, it is appropriate for leisure use and industry work. Thus, the multi-rotor drone operation is simple and can take off vertically, exclusive of a runway. So, its reliability mainly depends on the brushless motors, thus, it has higher reliability.

Simultaneously, multi-rotor UAVs have been extensively used in many agricultural and industrial fields with simple operation & strong stability. So, these drones are characterized by the above two rotors, including standard configurations like tricopter (three), quadcopter (four), hexacopter (six), or octocopter (eight) rotors.

Multirotor Drone Working

Multi-rotor drones work by using multiple rotors, normally 4, 6, or 8, to produce lift & control flight by changing the individual rotors’ speed by allowing maneuvers like ascending, hovering, turning, and descending.

Every rotor rotates to push air down, making an upward reaction force that lifts the drone. By adjusting the rotor’s speed evenly, the drone can ascend otherwise. Whenever the rotor’s combined thrust balances the weight of the drone, it can float.

By making the rear rotors turn quicker as compared to the front rotors, the drone pitches ahead, and vice versa. Thus, making one side’s rotors turn faster as compared to the other, the drone rolls in that direction. By making diagonally opposite rotors turn quicker than the others, this drone turns in that direction.

So the rotating rotors generate torque, which is counteracted within multi-rotor drones by having some rotors turn clockwise and others turn counterclockwise, which cancels out the whole torque. Drones utilize sensors, computerized positioning systems, and gyroscopes to maintain constancy and find their way in the air by allowing for accurate maneuvers.

Multirotor Drone Types

Multi-rotor drones are available in different types and used in different applications with performance variations in agility, flight time, payload capacity & stability.

Trirotor

The trimotor drone is made with three rotors to generate buoyancy, used for movement and control. So the arm distance is generally 120 degrees and is normally in a Y-shape at the same time in a T shape for sometimes. The benefits of this type of drone are low cost, flexibility, and its light size because it requires only three rotors, which is a fairly low-cost configuration. Simultaneously, it can also have low lifting power due to the motor numbers.

Quadrotor

It is the most popular and common type of multi-copter available in the X and H forms. So, four motors are placed on a symmetrical frame, and every arm is generally 90 degrees apart within the X4 configuration. Two motors turn in a clockwise direction, whereas the remaining two rotate in a counterclockwise clockwise to produce opposite forces to stay balanced. Thus, it achieves an ideal performance for stability, flight time, and price.

Hexacopter

The hexacopter is placed on a symmetrical frame, and every arm is generally 60 degrees. The hexadecopter includes more motors than the quadrotor to enhance stability and power. This drone can also improve high redundancy intervening time so that even if a drone’s motor fails throughout the flight, it can work correctly in the air & land securely. But, motors will have more power consumption, thus, the flight time will be reduced. So it can also be similar to a quad-copter where three motors turn clockwise and the other three turn CCW to produce reverse forces to keep balance.

Octocopter

The octocopter drone normally includes eight rotors with strong stability & power. It takes a greater payload with stronger wind resistance. This drone looks similar to an upgraded quadrotor & hexadecopter. These are frequently used for professional or film purposes and can be placed with heavier lenses and cameras. Its energy consumption is quick, and the size of the drone frame is large due to the increase in the number of motors.

Coaxial Multi-rotor Drone

This is a special type of multi-rotor drone known as a coaxial X8 drone, which uses eight motors arranged on four arms. It can be upgraded with more power & less space. It includes a set of rotors located on concentric axes with a similar rotation axis but rotating in reverse directions. Our product MX860 adopts the coaxial X8 drone frame that reflects the small in size & large payload features.

Multirotor Drone Components

A multi-rotor drone is made with different components, which include motors, frames, propellers, electronic speed controllers, flight controllers, battery & a remote control system, which are discussed below.

Frame

The frame in the drone works like a backbone, which provides mounting points mainly for all other components. It is particularly made with high-strength and lightweight materials like aluminum alloy or carbon fiber. Its design influences the overall weight, stability, and size of the drone.

Motors

The motors of this drone help in rotating the propellers by providing power and generating lift and thrust. These drones normally utilize BLDC (brushless DC) motors for reliability and efficiency. The type and number of motors mainly depend on the configuration of the drone, like hexacopter or quadcopter.

Propellers

Propellers are connected to the motors of the drone to produce lift and thrust by letting the drone fly. So the shape and size of propellers mainly influence the drone’s speed, lift & maneuverability. Propeller materials are carbon fiber, plastic, or other composites, mainly depending on the intended utilization of the drone.

Flight Controller

The flight controller works like the brain of the multi-rotor drone, which processes information from sensors to control the motor. So, it is responsible for stabilizing the multi-rotor drone within flight to maintain altitude to execute commands from the remote control. These controllers normally include different types of sensors like accelerometers, GPS modules, gyroscopes, etc.

Electronic Speed Controllers

Electronic speed controllers change the direction and speed of the motors by ensuring accurate control of the movements of the drone. Every motor normally includes its own electronic speed control, or else a multi-channel ESC can control several motors at the same time.

Battery

The battery of the drone supplies power to all the components like the motors, sensors, flight controller, etc. So, battery capacity decides the flight time of a drone, and various types of batteries provide varying act characteristics.

Remote Control System

The remote control system allows the operator to send instructions to the drone by controlling its flight path, speed, and altitude. The remote control typically includes a transmitter and a receiver, which communicate wirelessly with the drone.

Some Other Components

Some other components of a multi-rotor drone include landing gear, a Gimbal, a camera or sensors, propellers, a GPS antenna, etc.

• Landing gear provides stable support for drone takeoff & landing.
• A gimbal is a mechanical stabilization system that contains a camera or different sensors that allows them to stay level despite drone movement.
• Cameras or sensors are used to capture videos, data, or images.
• The GPS antenna of this drone is used for precise positioning & navigation.

Fixed Wing Vs Multirotor Drone

The difference between fixed-wing vs multirotor drones are discussed below.

Multirotor Drone Failure

Multirotor drone failure can be caused by different sources like propeller harm, motor failure & control system problems.

• Propeller failure can frequently occured because of rough landings or collisions; thus, it can cause blade harm, stability effect & control.
• Motor failure can be noticed with some methods like piezoelectric sensors, helping to recognize and lessen the effect of such breakdowns.
• Control system failure can lead to unbalanced flight, highlighting the requirement for strong fault-tolerant systems.

Other Factors

The other factors of multirotor drones mainly include the following.

• Environmental conditions like rain, weather conditions, and high wind can also main reason for drone failures.
• Operator errors like inappropriate handling and direction-finding can also lead to disaster.

Drone Failures Addressed

• Real-time fault detection systems execution, such as those utilizing IMU data & machine learning algorithms, is fundamental for premature warning.
• Control systems development can reimburse for motor breakdowns or other different faults, which allows for secure landing otherwise emergency maneuvers.
• Utilizing redundant components like flight controllers or multiple motors can improve safety and reliability.
• Regular maintenance and inspection of drone components are necessary to avoid failures.

Advantages & Disadvantages

The advantages of multi-rotor drones include the following.

• Multi-rotor drones stand out in tight spaces with precise movement and control, even in breezy conditions.
• Its design and assisted flight technology shorten operation.
• These can vertically take off & land by eliminating the requirement of specialized launching equipment and runways.
• These drones can hover in place, fly in several directions, and perform complex aerial maneuvers.
• These drones are more affordable as compared to fixed-wing drones.
• Many multirotor drones are portable and compact.
• These can have specialized sensors and equipment.
• They are applicable in different fields.
• The several rotors of this drone provide redundancy by allowing the drone to keep flying even if a minimum of one motor fails.

The disadvantages of multi-rotor drones include the following.

• Multi-rotor drones have limited speed and endurance, which makes them inappropriate for long-endurance monitoring, large-scale aerial mapping, long-distance inspections, etc.
• They are very inefficient and need a lot of energy to fight gravity and maintain them within the air.
• These are limited to approximately 20 to 30 minutes with the current battery technology while carrying a lightweight camera payload.
• Multirotor drones have lower speeds & range and limited flight time as compared to other types of drones.
• These are sensitive to wind, which impacts their suitability for long-distance or large-scale missions.

Multirotor Drone Applications

The applications of multi-rotor drones include the following.

• Multi-rotor drones capture high-quality images & videos from an exclusive aerial perspective.
• They monitor and track movement and areas to provide real-time visual data for safety purposes.
• These are equipped with different sensors that capture detailed geospatial information for models, creating maps & conducting topographic surveys within various fields.
• They can access hard-to-reach areas by enabling inspections of power lines, bridges, and infrastructures to reduce costs and risks.
• They can be utilized for tasks like pesticide & fertilizer spraying, land surveying within agricultural fields, and crop monitoring,
• These drones are valuable for assessing disaster areas or locating missing persons.
• Researchers use it for a variety of scientific purposes like geological surveys, biological research, and atmospheric studies.

Thus, this is an overview of multi-rotor drones, their working, and their applications. So the examples of multi-rotor drones are: tri-copters use three rotors; quad-copters use four rotors, hexa-copters use six rotors, and octo-copters use eight rotors. Among them, quadcopter drones are a very popular type of drone. Thus, here is a question for you: What is a drone?