DIY quadcopter repair

In detail: do-it-yourself quadrocopter repair from a real master for the site my.housecope.com.

In this article, we will look at how to repair a quadcopter with our own hands after a fall.

If you are having problems not with the frame, but with the attempts to take off, then see the article What to do if the quadcopter does not take off.

So, today quadrocopters have two types of frames - a closed case and an open frame with beams on which the motors are mounted.

Let's start with the open frame, but drone racing drones are more likely to get into accidents.

Our test subjects will be Eachine Racer 250, last summer I accidentally switched the flight mode and did not notice it, it seemed to me that the quad was going crazy and flying by itself 🙂

These were my first flights without GPS and I flew only in Agle and did not expect to go to Acro at all, I had never flown in it before, so I panicked 🙂

The consequences of the fall of the quadrocopter - a broken beam of the frame, even the propeller was not damaged.

The breakage points of the frame were lightly sanded and degreased with acetone.

A 30 minute epoxy was used as the glue. It is very convenient to store it in syringes - it is easy to dose and its dimensions are not large.

Epoxy is applied to the fracture sites - on both sides of the beam.

Then it is connected and fixed with a glue gun (if you don't know what it is, see the video below). Hot glue simply holds the beam until the epoxy cures. A very handy thing for temporarily fixing any details.

Then I added epoxy to the inside of the broken beam and waited for the epoxy to lose fluidity and left the broken drone overnight.

Overnight, the epoxy gained strength and it was possible to go flying.

Video (click to play).

Here is a video of the flight with the reconstructed beam.

Just in case, I ordered a spare beam, and before its arrival I flew on a restored one. I did not have any problems with flights.It turned out funny with him, he let a friend of his friend fly on a flight, the quad is stable, all modes are processed only through GPS, so I didn't worry, my children from 5 years old fly independently on it.After a while, I was distracted by a conversation, I stopped following the quadric, and an acquaintance of my acquaintance raised it by 30 meters despite the flashing lights and a clear desire of the quadrocopter to land (it lowers the engine speed on its own), in general, the quadrocopter fell down on a cutoff.An acquaintance of an acquaintance brought the fallen quadric, put down the remote control and faded away in quiet sadness. I haven't seen him again 🙂I filmed the restoration of the V303 quadrocopter body on video.

tweezers
cotton swabs
glue based on cyanoacrylate, do not take cheap, otherwise it will fall off
acetone
motor

Motors can be of different housings and they can have different grooves with a bearing, a shaft and a retaining ring. I have two types of engines:

As you can see, they also differ in the backlash between the bottom and the top. The motor on the left side has broken down, i.e. with an internal groove.

First of all, we need remove the retaining ring... On the right it is much easier to do it, but on the left it was difficult to do, as a result, even a piece of the eyelet at the ring from the left motor, which is with a groove, broke off:

Once you have removed the ring, do not lose it. Next you need halve (move apart) the two halves of the motor... You need to pull to the sides with your hands, it will be like this:

And here is our problem, the magnets that came off and touched the bottom of the motor:

If you look closely, it becomes clear that they are not on a straight line - who is lower, who is higher.

No need to remove all magnets, since they are located alternately - plus / minus / plus / minus, and to understand where the magnet has a plus and where a minus is, you will spend a lot of time:

Therefore, we do this:

Take tweezers and try to tear off any magnet, if it comes off, carefully remove it and we lay on the side with which it was glued - on the table:

Next we take cotton swab, moisten in acetone and clean groove in which there was a magnet from dirt. Wipe dry and clean side. There will be a lot of dirt, you can see it in the photo above. We also take a magnet, not forgetting which side it lies on the table and wipe the landing side with acetone.

We take a toothpick, drip glue onto it and gently, with a thin layer, grease the area in the dome, i.e. the groove from which the magnet was removed. Only do not pour a liter of glue there, the motor will spin very quickly, and this glue will create extra weight at this point, the motor will vibrate and wear out faster.

We take a magnet and quickly put it in placepressing firmly.

This is how we do it with each magnet that has fallen off.

After gluing the motor, we lubricate the rotor and bearings with oil (not sunflower oil, but machine oil, but better with weapon oil). After that, we put the retaining ring in place. This is another exercise in installing the ring in such a groove, not only can you not get there normally, it also spins on the rotor

That's it, try to twist it, if you did everything right, nothing will hurt anywhere and you can put it on the drone.

This is how you were able to repair the brushless motor with your own hands, there is nothing difficult in gluing the flying off magnets to the quadcopter motors.

Repairing DJI drone models is one of the most common questions when buying drones from this brand. Where to buy spare parts, how much they cost and how to make repairs yourself - all these questions remain open. But in this issue I will try to give detailed information and try to answer these questions.

Many companies represented on the Russian Internet that are engaged in drone repair offer their services, but there are users who are wondering how to repair a DJI drone yourself. It would seem that this can save money, because there is nothing difficult in repairing a quadrocopter. And they will be partly right, but not quite. After all, repairing a quadrocopter requires attention to detail, and it is better when this repair is carried out by a specialist who has repaired more than the first drone. By the way, his hand is full and errors in repairs are minimized.

As we all know, DJI makes quality drones with good performance. It would seem that such a quality of repair can be 100% avoided. But no. This is a thing, and like any other thing, care is needed. Actually, the quadrocopter also needs care. The main breakdowns that they may have are:

software crashes and breakdowns;
drone crashes and crashes;
consequences of long exploitation;
the consequences of wear;
the sticks on the control panel are not located in the center, but deviate;
an error is given when receiving the SSID;
breakage of the camera and other components after falling;
GPS navigation does not work;
the fall of the drone into the water;
the battery does not hold a charge and quickly runs out;
the motherboard is damaged, or its individual components;
cracked or damaged propeller;

If you have a breakdown from the list above, my advice to you is to make repairs at a service center or from private craftsmen. You shouldn't do this on your own if you don't understand it.

There are probably people in your city who will repair a DJI drone for a small fee and they probably have the necessary parts and spare parts.

I will give a small table in which I will write down the average prices for repairing a DJI drone. As long as this article exists, the information is relevant. If you notice any inconsistencies, write your comment.

I warn you: there are a lot of letters, photos too. But I hope that my experience will be useful and / or interesting to someone.

This story began about a year ago, when, after watching / reading all the information about quadcopters, I decided to get myself something similar.

At first, a toad pressed on something expensive, and the fear of inexperience to kill a flying car on the asphalt took its toll. It was decided to take a Chinese girl - and I will learn how to operate, and if I drop it, it’s not so scary. I stopped my choice on this one.

This photo, if anything, not mine)))

This is Syma X5C. From experience in management, I can say that this aggregator can be considered ideal for beginners and inexperienced.

Indestructibility - fell from 15 meters to the trampled ground - and nothing)))

Price - I took it for 3500r a year ago (with 5 batteries included)

You can practice at home - the copter is relatively small

For this money there is a camera))) There is one - and thanks for that)

Lightweight - blows away with a bang. Also, in a small room, it can be demolished by its own streams, reflected from the floor and walls.

The quality of videos and photos is poor

Nuance: if you turn off the remote control before stopping video recording, then what is it? That's right - it won't be saved)

Motors are not very durable - brushes burn

I bought additional screw protectors for it (I broke one on a tree, dropped the other on a fiddler (don't ask)) for 200r (8pcs) and an additional set of motors 300r (4pcs).

All of the above was purchased from a well-known Chinese store)

But this is all lyrics. In general, over the summer I ran into this kid and I wanted more.

To attach a suitable camera, so that the wind does not blow away, and so that he himself comes back to me.I suffered for a long time, choosing between different RTF (ready-to-fly) copters, but somehow it didn't work out.

And somewhere in October I decided - I want to build on my own! Well, I'm not an engineer or something.

For about a month, having climbed the thematic sites, I figured out what to take, how much it would result in me and whether it was worth it. The shopping list was compiled and I proceeded directly to the search for the best prices and directly to the purchase.

So what do we need in order to build a quadcopter?

1. The frame is, in fact, the basis of our machine, on which all the rest of the good that is lifted into the air is hung. My choice was Alien Reptile. It cost 1200 rubles from our Chinese friends. Carbon plates, plastic beams. This is how it looks when assembled:

That's what you need) and even a Velcro tape for the battery was sent)

2. Motors and ESCs (regulators) - I chose for a long time, toiled like a toad. I chose a budget kit, 920kv motors, 30A regulators. About 3800r for everything.

A small note: as it turned out, the motors have connectors for connection (“male”), but none on the regulators. I had to urgently order the connectors (because in Moscow time they cost some sort of scrap money). More about connectors in step 5.

3. The controller is the copter's brain that controls everything the copter does. My choice was APM. Lured by a set of flight modes, support for GPS and telemetry. Also, it will be possible to attach a gimbal for the camera to it without any problems in the future (and not only, in principle, any periphery is possible). I immediately ordered a set (I paid around 6800r, if my memory serves me right), which included:

b) Vibration support for the controller (so that our electronic brains do not have a shock from vibration)

c) GPS-module (also known as a compass)

d) Telemetry modules (so that, say, on a laptop or tablet, you can see the parameters of copter systems in real time)

e) Power module (in essence, it is a branch of the power cable to power the copter itself)

f) A bunch of different wires)

4. All this beauty must be fed from something. You need a lot of energy, therefore I chose such batteries for myself (I took new ones from my hands through the forum of the profile community) 4500 rubles per pair.

By the way, I re-soldered the connectors on the batteries (replaced with XT60) for compatibility with the power module and the rest of the electrics.

5. Since I started talking about an electrician, I also bought power wires in a silicone sheath (12AWG, the thickest, unfortunately there are no pictures of them) for 140r (2 pieces of 1 meter each), a heat-shrinkable tube and “bullet” connectors for connecting regulators with motors for 360r.

6. We need to somehow correctly organize the distribution of power from the battery to the regulators. To do this, use either a power distribution board or wired connections. I preferred the board. 160 RUR

7. By now, I think a lot of people have asked the question: “no, well, of course, that's good, but how does this guy hope to launch a drone without propellers?” And here they are) 400r / 8pcs, took with a margin.

8. By the way, the propellers that come with Ali are usually unbalanced, so additional vibration and dangling of the copter may occur. I bought myself a balancer. It's a long time to wait from China, so I bought it in Moscow. 925 RUR

9. Well, and the last point in order, but not in meaning: radio equipment. This is the part that makes the unmanned aerial vehicle)

Having rushed through the offers, I realized that the new app would cost exorbitant money.

Therefore, I bought myself a used, but in excellent condition, Turnigy 9XR equipment with a FrSky DJT transmitter (because the stock of this device is poor in some modifications, and in some it is absent). 4000 RUR The price is more than decent.

10. And, finally, what will connect the device with the copter and will act, as they say, on its behalf: the receiver. Took, again, used from hands, compatible with the transmitter. FrSky D8Xr-II. 1200 RUR

I also bought 5 pairs of XT60 connectors for 425r, to connect the power distribution board to the regulators. But if you don't need a detachable connection in this place, you can get by with one XT60 “male”.In one of the next posts I will tell you exactly where.

In general, this is all that is needed from the components. The cost came out a little less than 23,000 rubles, if you leave the balancer outside the brackets (because you can take it from someone to drive it or ask for beer / ice cream / chocolate to balance your props), but, I confess, I was very lucky with the price of the equipment and batteries.

The post uses pictures impudently taken from open spaces and pictures taken on YotaPhone 2, borrowed from his wife.

Today I'll get down to soldering the power distribution board and, if time is enough, soldering the connectors to the ESCs. If anyone is interested, I will tell you more about this in the next post, which I will try to release as soon as possible.

The reasons why hobby drone breeders think about how to assemble a quadrocopter with their own hands are different. For example, some people are not satisfied with the prices, some want to install their own camera, which is not installed on any gimbal, others want a configuration only for racing. But you never know what else!

What is a quadlet

The general principle of the drone

Assembly instructions for a simple drone

The second way to assemble a quadcopter with your own hands

Next, we will tell you about the important components that should be on board your drone. So that you know where, in fact, you need to start building your air "house" and what important details will be useful to you.

For those who are not yet in the subject - this is a structure, a platform, a structure, an aircraft, to whom it is more convenient, which (if we are talking about a platform) is controlled by a transmitter. Has 4 motors with the same number of screws. In the assembly of such aircraft, there is certainly a flying multi-engine platform.

When the drone takes off, it takes a horizontal position. Like a helicopter, it is capable of hovering above the ground at different heights. Flies in different directions. Previously, copters only knew how to fly towards their nose. It was only in recent years that Headless-type models began to do this, when a drone during flight could fly sharply in any of the four directions, without turning its nose in this very direction.

The aircraft is capable of lifting and lowering, while always remaining level with respect to the ground. If special equipment is installed on it, then in some cases it can fly even in autopilot mode. Most air amateurs use such opportunities, first of all, in order to focus at this moment on aerial photography, and not to show the world their aerobatic skills.

As we said earlier, the system is multi-rotor. These very rotors create powerful diagonal rotation in opposite directions. These rotors have a so-called manager that collects information from three or six gyroscopes (the number of the latter depends on the configuration of the copter) and transfers it to the rotors.

Gyroscopes (what a complicated name), gyroscopes were created in order to automatically determine the position of the apparatus during flight and then fix it in all three planes. In doing so, the accelerometer makes sure that the copter takes the ideal horizontal position. And in order to fix the quadcopter at a certain height, the flight system is equipped with a pressure sensor.

How does the copter move when all four propellers are spinning the same way? And due to a simple change in the rotation speed of one or another pair of motors. The result is a tilt of the copter, or as it is also called "roll" in the direction of the most weakly rotating screws and the copter flies horizontally.

In most cases there are strictly four rotors, but occasionally you can find copters with six or even eight propellers. Therefore, they are called multicopters, and the word "Quadrocopter" will no longer be relevant to the last two representatives of multi-rotor drones.

So, you already have a general idea of the details and modules of the future quadrocopter, now it's time to share with you how to assemble a drone with your own hands.

The first thing that comes to mind when building your own quad is, of course, its frame. There is nothing complicated with this element. For its base, ordinary 15 square centimeters plywood will do. The beams are adjusted using screws along the diagonal markings of your frame. The beam should be 30 cm long starting from the center of the aircraft. Beams - 25cm. We will postpone the holes for the engines themselves to the very end of the hull creation, having previously made the markup for the engines.

First of all, we install the control board. In doing so, place it as close to the center of your platform as possible. Therefore, from the very beginning, make the necessary, and most importantly, accurate measurements in this case, the device will not skid from side to side during the flight. Use self-tapping screws long enough to screw the beams to the board. The aluminum strap is suitable for boarding skis and for holding the battery.

Place the receiver close to the board. You can use some powerful superglue to mount the receiver. A simplified version of the connection with two three-core loops is possible in the case when the receiving channels are the same as the channels of the control board for their purpose. Keep this in mind.

As usual, before inserting it, you need to accurately mark the beams and make holes for the engine itself. Do your best to make the distance from the edges to the axis of rotation equivalent. At least as far as possible. When the engine is installed, a gross tail will stick out from its bottom. Therefore, you need to make a special hole for it.

When drilling the mounting holes, drill the full width of the square and through. Then you can immediately see whether the shaft will catch on the edges of this square.

Using adapters, make a parallel connection of 4 power wires. In the place where the battery will be connected to all four wires, you will need to use detachable connections. In other places, a soldering will be necessary, then tighten all the parts in heat shrink so that during strong vibration (when the copter will fly) something does not jump out and disconnect.

Now let's take care of the control board and connect the driver wires. Basically, after this operation, you can do a small check and fix the problems that will come to light during testing.

It doesn't matter which way you assemble your first prefab aircraft, there is one thing you need to remember. Do not spare money for the parts from which you will assemble the drone. Only in this case, with a greater degree of probability, you will get a better assembly and minor inaccuracies and errors will be forgiven you, well, or almost forgiven.

When assembling our quadcopter in the second way, we will consider the option using the Arduino Mega, Mega-Pirate firmware.

What do you need to build? 5 motors including 1 spare motor. Also get two sets of blades, one working, the other also for stock. We remind you that there should be two regular screws and two reverse rotation. Speed regulators. There must be at least four of them (if you are assembling a quadrocopter). And again, at least the same number of spare.It is better to take a smaller battery for such a drone so that it does not weigh down the drone. We advise you to use several small and light ones. Yes, the drone will fly less during one life cycle of such a mini battery. But at the same time, your flight will be more stable. Moreover, the process of replacing the battery will not take much time.The frame for your quadcopter should be light and strong at the same time. Remember the frame we described in the first case of self-assembly. So, such a frame is quite suitable for this option.From the electronic filling will be required: an "All-in-one" board, an accelerometer, batteries, a microcontroller, a gyroscope, as well as many bolts, screws, wires and various types of ties. Also, don't forget the soldering iron and drill.When you are sure that you have everything you need in stock, then you can safely start assembling. The assembly process can be repeated using the first method described above. Most importantly, the distance from each end of the beam to the center of the frame is the same. Make sure that the propellers are not touching each other and, importantly, the center of the frame.Because this is where the electronic brains of your drone will be located, plus a video camera, which, by the way, can be installed at will.If you mount your sensors in rubber or, say, silicone mass, then the vibration force during the operation of the propellers will be extinguished. As a chassis, you can make and fix foam at the very ends of the beams. For a softer fit, you can rubberize them or attach foam rubber.Well, if you do not want to assemble the board yourself, then we recommend that you buy a ready-made board on which 4 sensors are already installed, a gyroscope that will measure angular acceleration, an accelerometer that measures acceleration, a barometer that is responsible for choosing the desired altitude and holding the quadcopter. on it, as well as a magnetometer, which is responsible for where the drone will fly.Today it is quite easy to find the required firmware, download and install. After uploading it to the Arduino, download the setup program. After starting the program, you will be taken to the "Options" menu, there enter the COM-port of Arduino and in the Action menu - AC2 Setup. In order to set up the quadlet correctly, try to strictly follow the instructions (prompts) during the installation and operation of the program.So, for example, in one dialog box, you will be prompted to move the levers on the transmitter to the highest and lowest values, and in another, you will be asked to control the position of the copter. It must be level for accurate sensor calibration.When the calibration is complete, you will need to open the A5 from GND and in the menu, in the AC2 Sensor item, find the Raw Sensor tab to check if the sensors are working correctly. In this case, you need to focus on the arrow During the rotation of our board, the arrow should reach the desired value. If this does not happen or, on the contrary, it goes off scale, then you have problems with sensors or coefficients in the code.The transmitter is checked as follows, if the levels move as expected, then when you press the throttle lever for a couple of seconds to the right and down, you will have a red diode blinking. If you move the stick up, then the indicators should be identical, that is, the LED should turn red again.It's time to take off. Before doing this, set up the multicopter at a distance of about 10-12 meters from you. Tilt the throttle lever down and to the right. The copter will have to take off. If, instead, it is stationary, the propellers are working, and it is shaking, then it will be necessary to adjust the PID configuration in the corresponding menu.

The classic configuration of a quadcopter (drone) frame, which is used in most cases of DIY assembly. Variant shown with installed motors and controller

Other dimensions of the quadcopter (drone) frame, different from the stated ones, are not excluded, but one should not forget about observing the proportions. The joining of the frame parts is usually done with nails and glue.

Instead of wood, it is allowed to use metal or plastic of the same dimensions. However, the ways of connecting the strips will be different.

Below is a list of ready-made carbon drone frames available on the market:

LHI 220-RX FPV
Readytosky FPV
iFlight XL5
RipaFire F450 4-Axis
Usmile x style
Readytosky S500

For the manufacture of a classic quadrocopter (drone), you must have 4 engines. Accordingly, if the octocopter project is conceived, eight engines will already be required.

Brushless motors are recommended. This type of electric motors puts less stress on the battery, which is an important criterion for the operation of drones.

One of the options for the manufacture of propellers for motors of a quadrocopter (drone). Rigid plastic was chosen as the material, taking into account the small dimensions of the structure

In Russian, the ESC (Electronic Speed Controllers) module of a quadcopter is called an electronic speed controller. It is just as important a part of an unmanned aerial vehicle as an electric motor.

The ESC modules are responsible for the correct transmission of power to the drone's motors. The number of quadcopter modules corresponds to the number of electric motors.

Here are some of the recommended motors for quadcopters (drones):

Emax RS2205 2600KV Brushless Motors
DLFPV DL2205 2300KV Brushless Motors
Gemfan GT2205 2650KV Brushless Motors
HOBBYMATE Quadcopter Motors Combo

And in addition to the list of recommended speed controllers:

35A ESC BlHeli32 32bit DSHOT1200
Thriverline Sunrise ESC 20A BLHeli-S

Propellers can be purchased in metal 9-inch. These products are freely available on the market at an affordable price.

Metal structures are strong, do not lend themselves to bending at high loads during flight. However, for higher propeller performance, carbon propellers are the best option. For example, these:

BTG Quick Release Carbon Fiber Reinforced Propellers
Performance 1245 Black Propellers MR Series
YooTek 4 Pairs Foldable Quick Release Propellers
Myshine 9450 Self-tightening Propeller Props
Jrelecs 2 Pairs Carbon Fiber Propellers

A set of electronics for drones (quadcopters) traditionally consists of a flight controller and a wireless control system. The power module can also be attributed to this, since most of the power modules are endowed with an electronic battery monitoring system.

The state of charge of the battery is an important aspect of the flight. It is difficult to imagine what will become of the device if the battery is discharged, for example, during a flight over a reservoir.

The flight controller maintains the stability of the quadcopter flight by processing data regarding the direction and strength of the wind, as well as many other parameters.

Flight controller on the STM32F103C8T6 chip: 1, 2 - buzzer (+; -); 3 - stream; 4 - RCCI; 5 - case; 6 - 5 volts; 7 - battery; 8, 9 - UART TX, RX; 10 - bar indicator; 11, 12, 13, 14 - motors; 15 - PPM

The controller, as a rule, is equipped with the so-called "firmware" - a memory microcircuit, where the basic information for a chip similar to the AVR microcontroller is recorded.

The flight controller can be bought ready-made, but it is also possible to assemble the circuit with your own hands. True, for the second option, you need to have the skills of an electronics engineer and the corresponding knowledge of programming. Therefore, it is still easier to use ready-made solutions. For example, one of the following:

ArduPilot - high-quality controller (expensive) designed for unmanned aerial vehicles. The firmware is distinguished by the presence of fully automated flight modes. The system provides high technical characteristics.

OpenPilot CC3D - a system based on the Digital Motion Processor, endowed with a whole family of flight control sensors. Includes 3-axis accelerometer and gyroscope. The project is quite easy to configure and install. There is a user manual.

NAZE32 - is also a fairly flexible and powerful system, but it seems somewhat complicated in terms of customization. Equipped with an advanced firmware program.

KK2 - one of the popular solutions that beginners often choose, since the controller is relatively inexpensive and is equipped with an LCD display. The basis of the circuit is the AVR microcontroller, one of the latest modifications. The circuit provides for the connection of MPU6050 sensors. However, the setting is only manual.

The wireless remote control system consists of a radio transmitter and receiver. The remote control system not only controls the flight, but also controls the position of the video camera installed on the drone.

The control panel of the drone (quadcopter) in the classic variation of the radio signal transmitter with the ability to monitor via the LCD display

Here, as a rule, only ready-made solutions are used. For example, any of the remote control systems in the list below:

Futaba 10JH 10-Channel Heli T-FHSS Computer Radio System
Turnigy 9xr PRO Radio Control System
Spektrum DX8 Radio Transmitter
YKS FlySky FS-i6 2.4GHz 6 Channels Radio Control System

Electric motors are installed on the created frame. You may need to calculate the locations of the motors and drill holes in the frame for mounting if no other options are available.

Approximately according to this mechanical scheme, it is recommended to fix the electric motors on the frame of the quadrocopter (drone). True, much in the mount depends on the material of the frame.

Then the speed controllers are mounted. Traditionally, these modules are installed on the underside of the frame. The speed controllers are connected directly to the motors via ribbon cables.

Next, a landing module is added to the frame - a part of the structure intended for organizing a "soft" landing of the drone. The design of this structural element should be designed to mitigate impacts when landing on firm ground. Designs are possible in different ways.

The next step is to mount the flight controller. The location of this module is not critical. The main thing is to ensure the protection of the electronics and uninterrupted operation.

It is recommended to place a piece of spongy material under the electronic board to dampen vibrations transmitted by the operating electric motors of the quadcopter.

The aircraft flight controller is connected according to the attached diagram to the module (receiver) of the remote control and to the electronic board for adjusting the speed of the motors. All connections are made by means of reliable connectors, and the most important points "sit" on a tin solder.

Basically, the main assembly ends here. But you shouldn't rush to cover the drone with the body. It is necessary to test all systems - sensors and other components of the quadcopter, using special software OpenPilot GCS (CC3D and GCS). True, the release of the program is quite old and may not be supported by new developments.

Video (click to play).

After the test, the assembled device - the unmanned quadcopter is ready for flight.In the future, the drone is easy to upgrade - to equip it with a video camera and other devices that expand its functionality.

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