The drone hit the news headlines now and then, and it is indisputable that they are likely to play an integral role in the digital age. You can go for small helicopter-shaped aerial vehicles or learn how to build these exciting machines. We recommend the latter because we are still at the early stages of this revolutionary technology, and the best way to benefit from it is to understand it.
People use drones for commercial and private purposes and advanced military missions. There are currently several types of 'ready-to-fly' drones and drone kits in the market that suit all budgets and objectives. This guide is about building a drone, from the tools needed to build a drone to the materials you will use.
1. What is a Drone?
1.1 Drone Definition
A drone is basically a flying robot, which a user controls remotely via a software-based flight schedule. A drone is also known as a crewless or uncrewed aerial vehicle (UAV).
In the past decade, people used UAVs mostly for military operations, like anti-aircraft target activities, spying, and more controversially, targeted-killing in conventional war zones. Currently, people use drones in a vast array of daily activities, such as search and rescue, surveillance, traffic monitoring, weather monitoring, firefighting, photography and videography, agricultural mapping, anti-poaching campaigns, and even delivery services.
Although drones serve numerous purposes, their primary roles are flight and navigation. Like batteries or fuel, power sources, rotors, propellers, and frames are fitted into drones to enable them to fly. The frame consists of lightweight, composite materials to minimize weight and enhance maneuverability during flights.
The handler relies on a flight controller to remotely launch, navigate, and land safely. Controllers connect with drones through radio frequencies, including Wi-Fi. Navigation systems, like GPS, are fixed in the drone's nose to show the controller the drone's exact location. If available, an on-board altimeter gives altitude information and keeps the device at the specified altitude.
You can also mount different sensors into your drones. Visual sensors provide still or video data; RGB sensors gather visual red, green, and blue wavelengths, while multispectral sensors offer visible and non-visible wavelengths.
Some drones have obstacle detection and collision avoidance sensors. Initially, engineers positioned these sensors to detect objects in front of the device only. With innovation, drones can now identify objects in all directions: front, back, below, above, and side to side.
For safe landing, drones use visual positioning software with downward-facing cameras and ultrasonic sensors. The sensors detect how close the drone is to the ground.
2. Types of Drones
There are different types of drones based on 'usage,' such as photography and videography drones, aerial mapping drones, surveillance drones, etc. But, the best classification of drones is based on the aerial platform used. There are four main types of drones based on this classification: single-rotor helicopter, multi-rotor drones, selfie drones, and racing drones.
2.1 Single-Rotor Helicopter
A single-rotor helicopter contains one rotor and a tail rotor to regulate direction. Helicopters are quite common in crewless aviation, but rare in the drone industry.
A single-rotor helicopter is more efficient than a multi-rotor and can be powered using a gas motor for long-distance missions. Theoretically, the bigger the rotor blade, the slower the spins, and the more effective it becomes. The theory explains why a quadcopter is more effective than an octocopter, and long-distance quads have a large propeller radius. A single-rotor helicopter can accommodate long blades that act like a spinning wing, providing high efficiency.
If you plan to fly using a stable device or have a combination of flying with a durable or first forward device, then a single rotor helicopter is all that you need.
The drawbacks of single-rotor helicopters are their intricacy, cost, vibration, and massive blades' vulnerability. While a multi-rotor propeller can undoubtedly cause some scars to users, it is implausible to do much more than that. The long sharp edges of a helicopter can leave more severe injuries when you cross their way. Several cases have been reported, especially from the RC hobby and drone helicopters.
Regarding mechanical and operational complexity, the International Standards Organization rates single-rotor helicopters averagely. They can fly on the spot; hence, it is possible to begin easy and progress midway. However, in case of improper landing, they are unstable, and they also call for proper maintenance and care because of their mechanical difficulty.
2.2 Multi-Rotor Drones
Multi-rotors or multi-copters mostly have fixed-pitch propellers, and they obtain motion by changing the relative speed of the motors. Radio-controlled multi-rotors are preferred for aerial photography and land surveying because they can stand still on the air. They are easy to build, carry, and are the most cost-effective type of drones.
If you plan to fix a small camera for a short time, multi-rotor drones are the best option. Their drawback is short endurance and speed, making them unsuitable for large scale aerial mapping, continuous monitoring, and long-distance assessment, like pipelines and power lines.
While technology is advancing every year, multi-rotors are generally ineffective and need a lot of power to go against gravity and maintain flight. With the standard battery power, multi-rotors can only stay in the air for about 20 to 30 minutes when fitted with a lightweight camera. Heavy-load multi-rotors carry more weight but take shorter flight times.
Because of the high demand for fast and better accuracy control to give them more stability, it is impractical to utilize a gas engine to power them; hence, they only use electric motors. Until developers invent another power source, expect minor changes in flight time.
We classify multi-rotors according to the number of motors used, for instance, a three-rotor multi-copter called a tri-copter, with a configuration of Y3. The main reason for fixing several rotors is better to control the drone's position in the air. More rotors make a drone to maneuver well.
In this article, we will discuss tri-copter (three rotors), quadcopter (four rotors), hex-copters (six rotors), and octocopters (eight rotors).
Tri-Copter; 3-Rotor Multi-Rotor
The tri-copter contains three rotors, mostly in "Y" or "T" shapes, with the arms placed 1200 apart. Two propellers are fixed on the front wings and spin in different directions to counter each other out. The rear rotor can be adjusted in any direction by a servo to establish the yaw mechanism.
Tri-copter multi-rotor drones are common and relatively cheap since they only need three rotors and an extra servo. However, they are less stable among the multi-rotor family. They are also weak because of the openness of the tail servo and mechanics in crashes.
Quad-Copter; 4-Rotor Multi-Rotor
A quadcopter contains four rotors fixed on an asymmetric frame, with arms placed 900 apart. Two rotors spin in a clockwise direction, while the other spin anti-clockwise to create an opposite force. Quad-copter is the most common multi-rotor drone because of its simple mechanical structure.
Quadcopters have two primary configurations: X and +. The X configuration is more common since you can fix the propellers away from the camera's view in aerial photography and videography. On the other hand, the X configuration is quite intuitive and hovers like an aircraft.
Lastly, the H arrangement allows a camera to be fitted on the frame well forward to avoid placing propellers in the camera view.
Hexa-copter; 6-Rotor Multi-rotor
The hexacopter contains six rotors placed approximately 600 apart on asymmetric structure, with three clockwise and three anti-clockwise rotors. Hex-copters resemble the quadcopters very much, but they have more lifting power from the extra motors. They also have a better redundancy; if one rotor fails, the drone can maintain stability and achieve a safe landing. Their drawback is that they are often huge and more costly to construct.
Octo-Copter; 8-Rotor Multi-Rotors
An octocopter has eight rotors on the same level, with four sets rotating in a clockwise direction and the other four in an anti-clockwise direction. They resemble quadcopters and hexacopters. They are simply an upgraded version of the hexacopter with a better lifting power and redundancy.
But, since they have more rotors, they consume more current and require more battery packs. They are also a bit expensive. People mostly use octocopters in aerial photography and lifting heavy filming loads.
2.3 Selfie Drones
Selfie drones are mostly smaller than the other drones, and they are highly proficient in taking selfie photos and videos. While the other drones are well known for shooting high-resolution images and videos from a distance, the main stronghold of selfie drones is how lightweight, small and portable they are without conceding on power and image quality. Portability is their selling point, as most users want pocket-size drones.
When people think of drones, they imagine buzzing devices that everyone within 200 meters away sees and hears. The imagination is not applicable in selfie drones as they are quiet, stealthy, and stable little machines with similar benefits as other drones.
Selfie drones function just like other drones. You control them using a remote controller, or in some instances, a software application, and can hover for a certain period, in a specified range, taking photos and videos.
Some types are fitted with GPS and automatically return to their take-off points in case of insufficient power. They keep photos on an inserted memory card. Some enable real-time upload to the internet.
Selfie drones allow users to take photos of locations inaccessible to people. For instance, you can set your drone above a bridge and then make aerial footage of yourself walking along the bridge.
Another everyday use of a selfie drone is when you want your hands free or appear in a group photo with your friends. Usually, you are restricted by how far you can hold a selfie stick and what you want to do with your hands. Selfie drones fly in any direction you wish to; hence, you can have as many friends as you want in your group selfie, from all angles.
There are various types of selfie drones, such as DJI Spark Selfie Drone, Drone X Pro, JJRC H37, Skye Drone, etc.
2.4 Racing Drones
Those who think that the only uses of drones are taking videos and photos must rethink. First Person View (FPV) drone racing is taking roots rapidly, and it is one of the most thrilling technology sport. The good news is that it is open to everyone.
We can compare drone racing to a real-life video game. Pilots fly customized racing drones- fitted with front cameras that stream live footage to the FPV goggles- at almost 100mph around specialized courses consisting of barriers on all axis.
Drone racing has grown due to a blend of several technological advancements, like tracking features from smartphones, super visual reality software, and the trimness of the camera technology and sources of power. These advancements have significantly contributed to the popularity of drone racing.
The rapid popularity has led to the sprout of competitive drone racing leagues and formats attempting to transform this leisure time activity into the actual sport, with sponsors on board, racing rules, and broadcast partners. With the introduction of the Drone Racing League (DRL), drone racing has turned out to be a significant event and career path for many people.
There is a wide variety of racing drones in the market. They are all made up of a frame, four rotors, electronic speed controllers, a flight controller, video and controller transmitter, antennas, and an on-board camera. The other part the pilot needs is an FPV goggle.
3. Basic Tools Needed to Build a Drone
Basic tools refer to some of the must-have equipment required to build a drone. Besides, you will use most of these tools to repair your drone in case of a crash. These are the essential hand tools needed to build and repair a drone.
A multimeter is an essential tool needed to build a drone. The primary function of a multimeter is to detect voltage in electrical parts. You can also use it to check discontinuities and shorts caused by soldering and check battery voltage. An advanced multimeter contains extra measurement abilities and is more dependable and gives more precise results.
3.2 Soldering Iron
You need a soldering gun to connect electronic pieces. Besides, it is required to re-secure any part that disconnects as a result of crashing. Apart from the multimeter, a soldering iron is one of the essential tools needed to build or repair a drone. All the connection works require a soldering gun. You can also use it to create quads.
The difference between a soldering iron and a soldering station is the temperature measures. The temperature of a soldering iron is always constant, while that of a soldering station can be adjusted based on the solders' thickness.
3.3 Hand Tools
You will need hand tools to take apart, modify, and secure parts of your drone. Luckily, most of these tools are readily available in the market.
Hex drivers. You will use them to fix screws that hold a drone together.
Nut driver/wrench. You will need it to change propellers and remove nuts from the drone kit.
Pliers. You need pliers to reach spots and grip parts while using other tools. The most common type of pliers used is needle-nose pliers.
Wire cutters. You will need them to strip and cut wires.
3.4 Lighter/Heat Gun
You require heat to condense the heat shrink around wires. The most straightforward equipment in the market is a lighter- either an over-the-counter cigarette lighter or a long-handled lighter. You can also go for a more advanced heat gun for reliable heat production.
You will use tapes to cover zip ties. You also need an electrical tape to cover open ESC sections when the appropriate heat shrink is not available. Besides, you can use it to hold down wires and cables temporarily.
Double-sided tapes are useful in sticking ESC to the arms, hold receivers tightly, and mount the flashy LED as they contain excellent vibration dampening. Kapton is a special tape that withstands high temperatures and is mostly used to cover PCB during soldering.
3.6 Smoke Stoppers
When you construct a quad, you are not entirely sure that there is no short in your circuits. You need a smoke stopper when you power your device to prevent damages caused by short-circuiting. The bulb plays a fuse; when extra current flows through it, it burns to avoid any harm.
You require tweezers to hold down small electrical parts that are electrically sensitive. They are also used to access the hard to reach buttons. Tweezers are so helpful in the construction of a drone.
4.What You Need to Build a Drone
Technology has simplified the process of making drones like never before. Currently, there are drone kits on offer that you can acquire from your local shop. Whether you want to build from an assembled drone kit or scratch, these are the tools you need to navigate through the drone building process smoothly.
4.1 The Frame
Your drone requires a frame to host all the other parts. You have two options concerning a frame for your UAV. You can create it from scratch or purchase it from your nearest store. To learn more about the different frames, check out this article about the best drone frames.
Building a frame from scratch is not so challenging, but you have to learn some engineering basics and be aware of the right materials to use. For example, you can use a light metal, plastic, or wood slats. If you settle for a wooded frame, use a wood board that is 2.5 cm thick.
Your drone uses motors to rotate the propellers. A quadcopter uses four motors, while an octocopter needs eight motors to function. It is recommendable to use brushless motors as they have lighter batteries. For DIY drone fans who lack comprehensive engineering knowledge, buy your motors from a trusted dealer.
Since motors will define how your drone will function, choose the appropriate motors for your product's success. It would be best if you consider the length they cover, RPM, and power consumption.
4.3 Electronic Speed Controls (ESC)
An ESC is an electronic circuit that modifies a motor's speed and direction. It can also act as a dynamic brake. An electronic speed controller purposely converts DC battery power into three-phase AC to power brushless motors. Therefore, if you use brushless motors, you require an ESC, but you do not need them when working with brushed motors.
You should connect your electronic speed controllers directly to the power source using a wiring harness or power distribution board. They have a built-in battery eliminator circuit (BEC) that facilitates other parts' powering, such as the flight control board and radio receiver.
You need the 3.5 mm connectors to hold the motors and ESCs, and the 4.5 mm connectors for your power distribution board.
4.5 Flight Controller
The flight control board acts as the 'brain' of a drone. It comprises sensors, like gyroscopes and accelerometers, which determine the speed of rotation of the motors. Flight controls come in all sizes and shapes.
You require four propellers for a quadcopter drone; two propellers spin in a clockwise direction, and the other two in an anti-clockwise direction. The pusher propellers have a letter 'R' after the size. When choosing propellers, pick the ones that can fit well with your frame. Pay close attention to the materials- wooden propellers are not available, but you must ensure that the ones you select are an excellent fit.
4.7 A battery and a Power Distribution Board
They will act as the power source for your device. The power distribution board will connect the ESCs to the batteries to ensure adequate power flow. A battery monitoring unit is also needed to relay power from the drone to the controller.
When buying batteries for your drone, consider their capacity and type. Li-Po batteries are the best cells for drones.
4.8 A Mounting Pad
It will help minimize drone vibrations and achieve stability in the air. If you are planning to fix a camera into your drone, you will require a mounting pad.
5.How to Choose the Right Drone Parts
The process of selecting the appropriate parts for your drone requires a combination of both art and science. The main criteria you should consider is the Thrust to Weight ratio, also known as the TW formula.
We all understand that weight is the force that gravity pulls to the ground. Drones have mass, and they can only fly when they generate an upward thrust that exceeds their weight. Therefore, a TW of 2 implies that the drone exerts an upward force twice its weight.
Choose different TW ratios based on the use of your drone. For this purpose, you should set a target TW ratio before you start building your drone to assemble parts based on that ratio. For example, if you plan to make a good FPV racing drone, you should choose TW ratios above four. If you plan to build a drone that can carry heavy weights, consider TW ratios of about two.
5.1 How to Estimate the TW Ratio
To find the Thrust to Weight ratio, you should begin with establishing the weight of your drone. You will have to go through your part list and sum the weights of all the components. Let us assume that the estimated weight of the drone you plan to create is 2,000 grams. If your target TW ratio is two, this implies that you require a thrust of 4,000 grams. For an octocopter drone, each motor could have a thrust of 500 grams.
Finding the thrust of a motor is the work of the battery voltage, propeller size, and motor size. These features determine the thrust generated by a motor.
It is advisable to use motors from manufactures that offer thrust tables. These tables contain practical information indicating the grams of thrust you need under different aspects.
6. How to Build a Drone
Now that you have all the materials needed to make a drone, it is time to put them together. Follow these seven simple steps to build a quadcopter drone:
6.1 Create a Frame
You can use materials of your choice to build the frame. However, choose only materials that provide excellent structure and shape, like wood, plastic, or metal. If you select wood, use a wood board that is more than 60 cm long and about 30 cm wide. Divide it into two halves that are 60 cm in length and 30 cm in thickness. You need these two laths to make quad's frame.
To make an X configuration, you need to cross the laths. Besides, you need a wooden sheet to build and join a rectangular part in the middle of the frame. The rectangular piece should be six by 15 cm and 2 mm thick.
Different drones require different sizes; therefore, you can modify your drone size based on your needs. You require screws and glue to assemble your frame. If you go for metal or plastic materials, the measurements are the same. The only difference is in joining the laths.
6.2 Assemble your Drone's Motors
Make holes in your frame for the motors based on the distance between the screw holes. It is recommendable to drill an extra hole that will enable your device's clip and shaft to move freely.
Fix them to the frame using screws and a screwdriver.
If you are creating a drone from a kit, you will only need to fix your motors to the kit. Buy motors from an authorized dealer to warranty reliability and stability.
6.3 Mount your Electronic Speed Controllers (ESCs)
After assembling your motors, you will need to mount your ESCs to the bottom of your drone's frame. The strategy leaves enough space at the top for other parts. It is advisable to use zip ties to install the ESC tightly to the drone's frame.
Place your ESC and power distribution board on top of your frame and chop the wires to match with the circuits on your distribution board. The board has two circuits; the red ring is the circuit where you will solder all the red wires to, while the black ring is the circuit where you will solder all black wires.
Before soldering, apply some solder on all your connections. After that, in the wires. Tinning is the process of coating wires with a soldering gun to link better with the solder on the power distribution board.
Now solder your Electronic Speed Controller to the distribution board. Leave the soldering gun on your connection until the wires can melt the solder. After that, place the wire on the link and hold the soldering gun till all the solder melts.
Ensure your connections are firm by pulling in various directions. A popping or cracking sound implies that you have a "cold solder joint." You need to re-solder your connections.
6.4 Fix the Landing Gear
At this stage, you will need to fix the drone's landing gear to absorb the shock when it lands on rough surfaces. You can make a landing gear in different ways; hence, you should apply your creativity to create a unique landing gear.
Readymade landing gears, like a water strider, are simple and easy to fix. You do not need to modify your gadget, attach it into your frame, and tighten it with straps. To detach it, you remove the straps.
6.5 Attach a Flight Controller
Attach a flight controller to your drone to enable it to achieve stability during flights. Ensure you attach a piece of sponge below your controller to eliminate the vibrations generated by the drone. Ensure that the arrow-pointing part of your flight controller aligns with the direction of your frame.
Fix the flight controller to the frame with holes in line with the standoffs. After that, tighten the nuts.
There are many ways of mounting a flight controller. For example, you can install it above the frame in your preferred direction, but you must ensure that all parts are fixed appropriately before calibrating your drone. You can also utilize zip ties to attach your flight controller.
6.6 Link the LibrePilot Software to your Drone
The software will enable you to control and test UAVs. You must also link your ESCs to the flight controller and your drone to the remote control first.
6.7 Test your Drone
Now that you have fixed the various parts of your drone take it for a spin before using it officially. Test your drone in an open place, away from buildings, trees, aircraft, and crowds, to avoid injuries and damage.
There are many aspects that you should consider during testing. First, you should assess if your drone is receptive to controls and flies well without drifting. Regarding your device's safety, ensure that it can lock onto GPS appropriately, and its return-to-home feature is functional.
7.Final Thoughts on How to Build a Drone
We have defined what a drone is and discussed the four main types of drones: single-rotor helicopters, multi-rotor drones, selfie drones, and racing drones. We went further and discussed drones that fall under each of these categories. The basic tools you require are a multimeter, a soldering gun, hand tools, heat guns, tapes, smoke stoppers, and tweezers. We also mentioned that the main parts of a drone are a frame, motors, electronic speed control units (ESCs), connectors, a source of power, and a mounting pad.
We highlighted seven primary steps of making a drone. Besides the steps discussed in this article, there are other intermediary steps because of the wide variety of drones, parts, programs, and tools. However, the guide contains knowledge and tips that you can apply to any model. We hope that we have instilled the confidence needed to carry you throughout making a drone.