The drone market in the commercial space has found great appreciation today. In spite of the great variations in uses, capabilities, and functionalities the drone market has to offer, it often becomes difficult to find one amidst all of that, or one that is just right for you. Look no further as it is very easy to make your own drone if you have the right components and the sense of completion and satisfaction to see it fly for the first time can never be matched by a drone one can buy online. So without further ado, let us start with the components of a drone builder and learn how to make a drone at home.
- Drone Frame
- Brushless DC Motors
- Electronic Speed Controllers
- Flight Controller
- Power Source
- RC Receiver
The number of arms your drone frame has determined quite a few of its aerodynamic properties. Multirotors include tricopters – 3 arms, quadcopter – 4 arms and so on. The quadcopter is by far the most popular.
The size of the drone for quadcopters is usually the distance between two diagonal arms measured in mm.
Brushless DC Motors:
In fairness, any properly sized motor can be used to turn the propellers of a drone. A brushless DC motor is nevertheless preferred over a simple DC motor as the latter is relatively less reliable and wears down faster. The specifications of such a motor usually have a KV rating. So if the motor is 1000KV, then the motor will spin at 1000RPM if 1 Volt is applied, 2000RPM with 2 Volts and so on. The torque a motor produces is also an important factor to consider. Generally, you get more torque the wider the motor is.
Electronic Speed Controllers (ESC):
When using a brushless DC motor is actually very similar to a small induction motor, which works on 3-phase AC. This is where the ESC comes into play. Connecting the ESC to a simple DC voltage automatically generates a 3-phase AC on its output, which can then drive the motor. It does have an upper limit for the maximum voltage it can handle and should hence be taken into careful consideration.
The specs of a propeller are generally represented with a 4-digit number, such as 8045. This simply means the diameter of the prop is 8.0 inches and the pitch is 4.5 inches. The higher the pitch, the more air the propeller moves with each rotation. A general rule of thumb is to pair high pitch props with low RPM motors as such motors provide more torque but spin slower which is offset by the prop that moves more air with each rotation and vice versa.
The flight controller is basically the control station for coordinating every other component of the drone to achieve the desired response. Its functions include things like coordinating individual motor speeds, converting the RC input from the user into flight behavior, etc. Flight controllers should come equipped with gyroscopes and accelerator which allows it to maintain drone balance and stability without any manual input. Open-source flight control firmware such as ArduPilot or PX4 can be installed in supported flight controllers to achieve desired control functions.
Choosing a properly deep power source is crucial as the maximum flight time, range, speed, etc might depend on the same. Capacity rating is given in mAh (milli-amp-hour). So if a power source is rated at 5000mAh, it simply means it can supply 5Amps of current for 1 hour. C-rating suggests how much current the power supply can continuously output. It can be found by multiplying the C-rating with the Ah number. Normally lithium polymer batteries (LiPO) batteries are used for flight purposes due to their high capacity-weight ratio.
The RC controller is a device that maintains radio connection between the drone and the pilot and receives commands from the same. It is connected to the flight controllers. Each type of movement takes up a single channel in an RC controller. So a minimum of 4 channels is used for establishing basic flight, dedicated to roll, pitch, yaw, and throttle respectively.
Steps to assemble the drone:
- Attach a motor to each arm of the drone frame.
- Mount an ESU for each motor and connect its outputs to the same.
- Attach propellers to the motor shaft.
- Mount flight controller somewhere centralized on the drone and connect ESU inputs to the flight controller.
- Mount the RC receiver to any convenient space on the drone and connect it to the flight controller.