The assembly of the drone frame requires a lot of patience and you are once again advised to follow the instruction manual when doing it for the first time. For reference, in this book, we will assemble a drone frame from HobbyKing (S500). Inside the box, you will get the items displayed in the following picture:

These items are listed here:

• Four frame arms (two blue and two black, if you buy the blue color)
• Four leg plates
• Two rods for the base mount
• One top plate
• One bottom plate for mounting the power lines
• And a lot of screws

Firstly, see the following figure and connect the parts as shown here:

Use a proper screwdriver to tighten the screws. Do not keep any screws untightened or tilted.

Let's connect the motors now.

The RC transmitter allows the drone pilot to control the drone wirelessly. It would be silly to fly a drone with a wire in the sky, so connecting the Radio Controlled (RC) transmitter is a must for a drone.

The RC transmitter sends signals and the receiver receives the signal. The RC transmitter is also known as the TX and the RC receiver is known as the RX. Before discussing about the RC receiver, let's know the transmitter first.

Basically, the transmitter is the remote controller of the drone. Before choosing a perfect transmitter, you need to consider a few things, such as the number of channels, the modes, and the frequency technology, and so on.

I would suggest you buy a good transmitter because this is the least thing that is destroyed while flying drones.

The number of channels gives you the ability to control how many individual...

We are almost finished assembling our quadcopter. Now the last part is to connect the battery. As we are using, S500 frame, it comes with a board, where you can connect the battery by soldering the connectors to the board and later just plug the battery while flying the drone. You can use zipties to lock the battery under the body of the copter, as shown in the following figure:

To summarize the connections, let's recap. The BLDC motors will be connected to the four-in-one ESC (or four individual ESCs). The ESCs will be connected to the ArduPilot's output pins (only signal cables, 5V, and ground cables). The power cables of the ESC (or ESCs) will be directly connected to the battery (in our case, we have connected on the body plate first and later used connector pins to be connected to the battery.). The radio and the RC receiver will be connected...

Binding is really important. Without proper binding, you cannot configure the drone's actions properly. You can bind your transmitter with at least the following things. Note that the binding process differs from the RC Receiver's model to model. The steps of the most common method is as follows:

• A binding cable
• An ESC
• A servo motor (or you can use a BLDC motor too, but it is too risky; I don't recommend it while binding the transmitter to the receiver)
• A battery

Firstly, connect the binding cable to the RC receiver on the BAT pin, as follows. In some models, the BAT pins might be known as B/VCC:

Now, take an ESC and connect the signal, 5V, and ground pin to the CH1 pins.

Connect the battery to the ESC. The ESC...

Just imagine your drone produces infuriating noises. Do you know why? It is because of the BLDC motors and the propellers, right? But theoretically, drones should not make that much loud a noise. Can you imagine why? Because of the proper uses of the aerodynamics inside a drone. The physics for flying a drone is really necessary to be known by all the drone pilots because, if you cannot master the air, your drone will not fly properly. Refer to the following figure to get a rough idea on how air is effected by the propellers of the drone.

The figure is taken from the NASA website. They simulated the aerodynamics via computers:

So, basically a drone (specially quadcopters) has two pairs of propellers (two in a clockwise direction and another two in a anticlockwise direction). The speed of each motor is individually controlled to...

You hardly can prevent your drone from crashing and breaking some of the propellers, or even the body. The damage will depend on the crash and the height it falls from. It will also depend on the surface your drone lands on or crashes.

The best place to fly a drone is open fields where there are no trees or any electrical wires hanging. Do not uplift the drone with high throttle at first, increase the throttle gradually. We will know about safe throttling later. For now, you can use the Stabilize mode first. Just remember, throttle is nothing but speeding up the velocity of the propellers of the drone. If you are a beginner, my suggestion is to learn how you can levitate your drone above the ground. Once you master hovering the drone, increase the throttle a little bit. Practice more with that high. Increase the height gradually. Then, start doing...

There are a few things you must check before flying a drone. Here is a checklist for flying a drone safely:

• Check all the connections
• Check transmitter and receiver bindings
• Check the battery charge and voltage
• Check whether all the propellers are attached tightly
• Check all the motor mountings
• Check all the screws
• Check the balance of the drone to see if any side is heavier than the other
• Always unplug the battery after flying; only attach the battery few a seconds before flying
• Check any obstacles outside
• Keep children away from the flying area
• Keep a distance from the drone while you first throttle it
• Turn on autopilot and return to the home/launch feature if they are available
• Do not fly a drone with unbalanced propellers or broken propellers
• Always wear safety glasses
• Maintain security protocols

There are some rules by the government of the country where you fly things in the sky, specially the drone. Always check the security protocols. A few common rules are as follows:

• You cannot fly a drone within 5 miles of an airport
• You must keep the drone within your eyesight
• You are not allowed to go higher than 400 feet (around 0.12 km)
• You cannot fly a drone in busy traffic areas
• You must register your drone if you use it for business purposes or professionally; you must have a license
• Always know the local rules before flying a drone

In this chapter, we have learned how we can assemble a basic drone or quadcopter. We have also learned about the aerodynamics of flying drones, some rules of not crashing drones, and the security protocols of flying drones.

In Chapter 3, Preparing Your Drone for Flying, we will learn how we can configure and tweak our quadcopter with proper modules and software to make it ready to fly, and then fly our first drone. I hope that will be really exciting for you. Let's start building and flying the quadcopter in Chapter 3, Preparing Your Drone for Flying.