What are drones? Drones, also known as unmanned aerial vehicles (UAVs), are technology that has no human pilot on board. Instead, they are controlled by a person on the ground or autonomously via a computer program.
They are not used just for war and military purposes, but also for everything from wildlife and atmospheric research to disaster relief and sports photography. Some companies provide the service of renting a personal drone to soar above the horizon and snap a photo or video. In this article, we put in one place everything you want to know about drone technology.
Is there a difference between a drone, UAV, and a quadcopter?
- “Drone” as a term is wrong, but regardless, it is commonly used. In other words, this is the term for unmanned aircraft, type undefined, but a blind flying robot of some sort.
- UAV or unmanned aircraft are essentially the same as manned aircraft, but without the body inside. The only real difference is that the operator directs them to their destination. Unmanned aircraft requires an electronic data link, so, unmanned aircraft might be fixed-wing airplanes, helicopters, lighter-than-air blimps, or some very creative hybrids.
- A “quadcopter” is a universal term for a rotary-wing aircraft with four main rotor systems and no tail rotor. The term doesn’t specify if the machine is unmanned, but common usage of the term these days has given it that implied qualifier.
Regardless of the above, it isn't a mistake to call almost any kind of remotely or self-directed vehicle a “drone”. All unmanned aircraft can be considered “drones” and in fact, it’s nearly impossible to come up with a current example of a quadcopter that isn't an unmanned aircraft or part of an “unmanned aircraft system.”
There are forums packed with people who want to build a drone but don’t know where to start. It can be frustrating to sort through the thousands of forum and blog posts to figure out what to do. We've made a list of the specific parts you will need for a complete drone build. Here is what you will need:
- Motor x4
- Electronic Speed Control (ESC) x4\
- Propeller x4 (2 clockwise and 2 counter-clockwise)
- Battery & Charger
You should also need to have some miscellaneous things like zip ties, double-sided tape, or velcro, a small amount of heavy gauge wire, battery strap, and some female to female servo leads or jumper wires. Let’s go over each part in detail.
Every drone or other multirotor aircraft must have a frame to house all the other components. Things you should consider here are weight, size, and materials.
The purpose of the motoris more than obvious: to spin the propellers. The market is full of tons of motors on the market suitable for UAVs, and usually, you don’t want to get the absolute cheapest motors available, but you also don’t want to break the bank when some reasonably priced motors will work.
Motors are rated in kilovolts, and the higher the kV rating, the faster the motor spins at a constant voltage. Most websites selling drone motors will indicate how many amps the ESC you pair it with should be and the size of propeller you should use. As a result of our research, we discovered that a 1000kV motor is a good size to start.
Electronic Speed Controls:
The electronic speed controlelectronic speed control (ESC), has the role to tell the motor how fast to spin at any given time. You must have four ESCs for a quadcopter, one connected to each motor. The ESCs are then connected directly to the battery through either a wiring harness or power distribution board.
Most ESCs come with a built-in battery eliminator circuit (BEC), which allows you to power things like your flight control board and radio receiver without connecting them directly to the battery. As the drone motors must all spin at precise speeds to achieve accurate flight, the ESC is important.
Arduino is a single-board microcontroller, intended to make building interactive objects or environments more accessible. The hardware consists of an open-source hardware board designed around an 8-bit Atmel AVR microcontroller, or a 32-bit Atmel ARM. Current models feature a USB interface, six analog input pins, as well as 14 digital I/O pins that accommodate various extension boards.
An Arduino board consists of an Atmel 8-bit AVR microcontroller with complementary components that facilitate programming and incorporation into other circuits. Official Arduinos have used the megaAVR series of chips, specifically the ATmega8, ATmega168, ATmega328, ATmega1280, and ATmega2560.
Arduino compatibles have used a handful of other processors. Most boards include a 5-volt linear regulator and a 16 MHz crystal oscillator (or ceramic resonator in some variants), although some designs like the LilyPad run at 8 MHz and dispense with the onboard voltage regulator due to specific form-factor restrictions.
An Arduino's microcontroller is also pre-programmed with a boot loader that simplifies uploading of programs to the on-chip flash memory, compared with other devices that typically need an external programmer. Using an Arduino is more straightforward by using an ordinary computer as the programmer.
A drone has four propellers, two “normal” propellers that spin counter-clockwise, and two “pusher” propellers that spin clockwise. The pusher propellers are labeled with an ‘R’ after the size.
UAVs use LiPo batteries which come in a variety of sizes and configurations. LiPo batteries also have a C rating and a power rating in mAh (which stands for milliamps per hour). The C rating indicates the rate at which power is drawn from the battery, and the power rating describes how much power the battery can supply.
Larger batteries weigh more so there is always a tradeoff between flight duration and total weight. A general rule of thumb is that doubling the battery power will get you 50% more flight time, assuming your drone can lift the additional weight.
LiPo battery charging is a complex process due to multiple cells within the battery that have to be charged and discharged at the same rate. Thus you need a balance charger. You can find many chargers on the market that will do the job, but be careful of cheap or off-brand chargers; many of them have faulty components and can cause explosions or fires.
You should never leave LiPo batteries charging unattended. Most people charge batteries outside on a cement area or in a fireproof LiPo bag (although the effectiveness of these is up for debate).
Those parts are the major components that you need to build a drone. It can be hundreds of possible configurations, which can make the process of choosing parts confusing for someone new to the hobby. We hope this list provided some clarity.
Types of drones:
There is a large variety of quadcopters used for military and civilian purposes around the world. These unmanned aerial vehicles vary in size from large solar-powered fixed-wing aircraft to minute helicopter-like devices fashioned on hummingbirds.
The US Congress made the decision that after 2015, drones should be given access to domestic airspace. Drones fall into one of six functional categories (although multi-role airframe platforms are becoming more prevalent):
- Target and decoy – providing ground and aerial gunnery a target that simulates an enemy aircraft or missile.
- Reconnaissance – providing battlefield intelligence.
- Combat – providing attack capability for high-risk missions
- Logistics – delivering cargo.
- Research and development – improve UAV technologies.
- Civil and commercial UAVs – agriculture, aerial photography, data collection.
What should you consider before buying a drone?
1. Not all drones are easy to fly:
If you want to purchase a drone, you should first know that anything that flies is going to be hard to control. A typical quadcopter is physically impossible to fly, but what keeps it stable is the computer inside (typically called the flight controller).
Every drone flies slightly different depending on how the flight controller is setup. Some flight controllers are setup for more agile flying, while others might be geared more towards stability.
2. Not all drones are ready to fly:
When you go to buy a drone, you’ll see a few common acronyms that pop up: RTF, BNF, and ARF.
- RTF means Ready-To-Fly. RTF drone usually doesn’t require any assembly or setup, but you may have to do some simple things like charge up the battery, install the propellers or bind the controller to the quadcopter (get them talking to each other).
- BNF means Bind-And-Fly. BNF drones mostly come completely assembled, but without a controller. With BNF quadcopters, you’ll have to use the controller that you already have (if it’s compatible) or find a controller sold separately. One thing you should know is that, just because a transmitter and receiver are on the same frequency that doesn’t mean that they’ll work together. In the analog days, if you had a transmitter and receiver both running on the same frequency they were almost guaranteed to work together. Now with digital communication that’s all changed. Even If your transmitter and receiver are on the same channel, they must use the same manufacturer protocols to talk to each other. So check to make sure that your controller will work with your drone before buying it.
- ARF means Almost-ready-to-fly. ARFs are similar to quadcopter kits. These drones usually don’t come with a transmitter or receiver and might require partial assembly. An ARF drone kit might also leave out components like motors, ESCs, or even the flight controller and battery. The definition of an ARF drone kit is very broad, so whenever you see ARF in the title, you should read the description thoroughly.
3. You need to make investment upfront:
You can skip this section if you just need something to fly around the house for $50. For the case you’re looking at spending hundreds (maybe even thousands) of dollars then you need to invest your time and money wisely following these steps:
- Invest in a good controller.
- Buy a good charger.
- Invest in research.
4. There are a ton of places to buy from:
Don’t worry if you don’t know where to purchase a drone. The market is full of online stores for drones that will ship to just about any major country. Many of the largest online drone retailers are located in either the USA or China, but if you look hard enough, you might be able to find a smaller store located near you.
We prepared for the list of the best websites for buying drones:
DJI: The #1 in popularity and name.
www.getfpv.com: high-quality FPV frames, components and more.
HobbyKing: The Walmart of radio control.
ReadyMadeRC.com: FPV components usually with better prices.
Quadrocopter.com: High-end aerial photography drones.
Amazon.com: A little bit of everything
HeliPal.com: Based in Hong Kong with products from DJI, Walkera, Tarot, etc.
BuzzFlyer.co.uk: A lot like HeliPal but in the UK.
xHeli.com: Mostly inexpensive toys with a little bit of higher end stuff.
5. You need to be part of a drone community:
We recommend everyone who owns a drone (or wants to buy one) to become a part of a community of some kind. Drone forums are a great thing, but you must know exactly what you're trying to ask, as well as where to ask and how to ask it. If you don’t know, your questions will go unanswered. This a list of the top drone forums:
My First Drone Beginners Group: Anything drone-related.
RCGroups.com: Anything radio control related.
DIYDrones.com: Geared more towards robotics.
FPVLab.com: Anything FPV related.
MultirotorForums.com: Anything multirotor related.
DJIGuys.com: Anything DJI related.
forum.FliteTest.com: Mostly foam airplanes with some drone stuff too.
That would be all. We hope this article gave you a better sense of direction when it comes to drone technology.