Getting Started With Drones
Among the most progressive applications of brushless motors is the drone. Let’s take a quick insight into what drones are and their types
What are Drones?
Drones, also known as unmanned aerial vehicles, are flying robots that can be controlled remotely or can fly autonomously using embedded systems
Drones are used for a variety of purposes including surveillance, traffic monitoring, weather monitoring, videography, agriculture, defense, etc. Drones have different features depending on the purpose they are being used
Drones consist of numerous components including electronic speed controllers, flight controllers, GPS modules, batteries, receivers, cameras, sensors, etc
There is no standard classification of drones. They can be categorized based on their size, range, endurance, or purpose. Let’s discuss the three main types of drone
Fixed Wing Drones
A fixed-wing drone comprises a rigid wing and resembles an airplane in looks as well as operation. These drones cannot be stationary in a position with vertical lift rotors. Instead, they glide on a fixed path till their energy permits
Fixed-wing drones are considered way more efficient than any other type of drone. They are quite popular in the military, where a manned flight turns out to be perilous or challenging. Fixed-wing drones can also be used for aerial mapping, agriculture, surveillance, etc
Advantages
- Fixed-wing drones have an impressive average flight time that can go up to 16 hours or more if it has a gas engine
- Fixed-wing drones can fly at higher altitudes
- Fixed-wing drones are more forgiving in the air than other drones
- Fixed-wing drones can carry heavier weights
Disadvantages
- Fixed-wing drones are expensive
- Fixed-wing drones require some training to be able to fly them with perfection
- Mostly, a launcher is required to get Fixed wing drones in the air
- Fixed-wing drones are more difficult to land compared to the other types
- Fixed-wing drones can only move forward and are incapable of hovering in the air
Single Rotor Drones
Single-rotor drones are robust and resemble a helicopter in structure. They consist of one big rotor on the top and a smaller rotor on the tail to help with direction and stability. Single-rotor drones are typically used for research, aerial LIDAR laser scans, and surveying
Advantages
- Single-rotor drones can hover vertically in the air
- Single-rotor drones are robust and durable
- Single-rotor drones have an impressive long-lasting flight time. The flight time increases if the drone is gas engine-powered
- Single-rotor drones have a heavy payload capability
Disadvantages
- Single-rotor drones are more difficult to fly than multi-rotor drones
- Single-rotor drones are expensive
- They have higher complexity
- They can be risky to use owing to the heavy spinning blade
Multi-rotor Drones
The most popular choice for a drone, especially for aerial photography and videography, is the multi-rotor drone. It is also popularly used for surveillance, leisure, agriculture, and construction. The multi-rotor drones have multiple rotors on their body
They can be further classified based on the number of rotors like tricopters, quadcopters, hexacopters, and octocopters having three, four, six, and eight rotors, respectively. So far, quadcopters are the most popularly used multi-rotor drones
Advantages
- Multi-rotor drones are the easiest to manufacture
- Multi-rotor drones are not very expensive
- Multi-rotor drones are easy to control and maneuver
- These drones can take off and land vertically
- These drones have high stability
Disadvantages
- Multi-rotor drones have a shorter flying time
- These drones have smaller payload capabilities
- Most of this drone energy drains in defying gravity and stabilizing in the air
Other Types of Drones
- Agriculture Drones
- Surveillance Drones
- Mapping Drones
- Defense Drones
- Delivery Drones
Performance Evaluation
Flight
Drones can be designed and programmed to perform combative maneuvers. They can also be engineered to land or perch on inclined surfaces to then climb toward better communication areas
Certain drones can be programmed to control flight with different flight modelizations like the VTOL designs. These unmanned aerial vehicles can also perform perching on flat vertical surfaces
Endurance
Many large unmanned aerial vehicles (UAVs) use the Wankel Rotary Engines, owing to their smaller size, lighter weight, lower vibrations, and higher power-to-weight ratio. This engine is used as it is not susceptible to shock cooling during the plunge. Also, it does not need an enriched fuel mixture for cooling at higher power. These parameters help decrease fuel usage and enhance the range or payload
A proper cooling system in the drone is crucial for enduring it
for a longer period. Overheating and consecutive engine failure are among the common causes of the failure of UAVs
Hydrogen fuel cells are capable of extending the endurance of smaller drones for up to several hours. So far, micro unmanned air vehicle endurance has been best achieved with the flapping wing drones. Following these shall be the planes. The least endurance is achieved by multi-rotors due to the lower Reynolds number
The solar electric drones have accomplished impressive flight times of several weeks. Electric drones powered by laser power beaming or microwave power transmission are other possible endurance solutions
A very popular application of high-endurance drones is to keep an eye on battlefields for long intervals. They record events that can be later observed to track battlefield activities. Some examples include ARGUS-IS, Gorgon Stare, and Integrated Sensor IS Structure
Reliability
The improvements in the reliability of the UAVs aim at all aspects of the drone systems using fault tolerance and resilience engineering techniques.
The reliability of a drone includes the strength of flight controllers, dynamic evaluation of flight envelope, software accountability, etc
A crucial reliability metric is represented by the mean time between failures which is expressed in hours of operation. The higher the value of the mean time between failures, the more the reliability of the drone
This should give you a good idea about what drones are. Further, we will discuss the
drone propagation system
