Drones: specifications, types

General drone specialization.

This parameter is specified in cases where the device has a clearly defined specialization and is noticeably different in equipment/functionality from conventional quadcopters for entertainment purposes. In our time, the following types of drones are distinguished: mini-drones, racing vehicles(including in the form of racing mini-drones), selfie drones, kits for battles, as well as industrial/commercial solutions. Here are the features of each of these options:

— FPV drones. Quadcopters with a “First Person View” transmit the image visible to the camera in real time. Those. During such a broadcast, the operator will see on the screen the same thing that directly falls into the field of view of the lens. This can be useful for photo and video shooting from the air, more precise control of a drone, and performing a number of specific tasks for reconnaissance or military purposes. Smartphones, tablets or other similar gadgets are used to view images from the camera; there are also remote controls with built-in screens (see “Display for FPV broadcast”) and specialized masks like virtual reality glasses (see “Helmet for FPV broadcast”).

— Mini-drone. Miniature devices with dimensions of no more than 150 mm (length a...nd width) and a weight of no more than 100 g. This allows them to be easily transported from place to place, as well as to fly even in confined spaces - right up to city apartments. At the same time, many mini-drones are intended exclusively for entertainment, but there are also models with quite advanced characteristics. But the communication range of such equipment, as a rule, is quite limited (although, again, exceptions are possible); the same applies to carrying capacity.

- Racing. Devices originally created for drone racing. Such races require not only fast completion of the tracks, but also the ability to accurately fit into a given trajectory; Therefore, racing quadcopters differ not only in speed, but also in control accuracy. In addition, among such machines there may be modifications for complex aerobatics (freestyle, 3D) - in their characteristics the emphasis is even more shifted to accuracy and responsiveness. It should be borne in mind that most racing models are not only expensive, but also quite difficult to operate and are designed for experienced pilots; so it hardly makes sense to buy such a device for initial training or entertainment use.

— Racing mini-drone. A variation of the racing machines described above, characterized by reduced dimensions and having corresponding features. On the one hand, these features include ease of transportation and the ability to be used in confined spaces, on the other hand, a relatively low load capacity and communication range.

— Selfie drone. Copters designed primarily for taking selfies. Among the main features of this technology are its small dimensions and the absence of a classic remote control: control is carried out either via a smartphone or using gestures through a special compact controller. This format of work eliminates the need to carry a bulky remote control and allows the operator to look natural in the frame - posing for a photo, rather than being distracted by controlling the drone. And some advanced models provide additional functions that make shooting even more convenient: face detection with autofocus and auto-centering, Follow Me mode (see “Flight Modes”), etc.

— Industrial/commercial. High-quality copters designed for professional use: photographing and video shooting from high altitudes in high resolution, “inspecting” industrial facilities and land plots, spraying fields, etc. In addition to their large dimensions, they are characterized by a long range and flight altitude (and even and others are usually calculated in kilometers), high carrying capacity and extensive functionality. Thus, many models allow the installation of heavy advanced cameras (some are even initially designed for certain models of professional cameras), others have built-in “optics” with advanced capabilities (for example, with a high magnification factor or support for shooting in the IR range). The design usually includes a large abundance of sensors. And some models may have more specific functions - for example, detecting other aircraft nearby. Of course, such functionality is not cheap.

— Combat (sets for battles). Drones designed to organize air battles. As a rule, they are sold in sets of two cars - so that the fight can be organized immediately, without purchasing anything additional; and most models allow you to organize group battles (at least “all against all”) - for this it is enough to buy several identical sets. The role of the “gun” in such a copter is usually played by an IR emitter, and hits are recorded using appropriate sensors. For control, a smartphone or other gadget is usually used, and the control application can provide very interesting and unusual functions - for example, statistics for each player with experience points received for battles, as well as special “skills” (temporary invulnerability, unusual maneuver, etc.) . p.), purchased for these points and activated by clicking on the corresponding icon in the application.

The diagonal distance in inches between opposing drone motors. Aircraft with frame sizes less than 7 inches are conventionally classified as Micro, while those with frames 7–8 inches and 9–10 inches are included in the Mini category.

The size of the frame directly affects the maximum diameter of the propellers, in inches, that can be installed on the drone. If the copter is built on a 7-inch frame, then the permissible diameter of the propellers for it will also be 7”.

The distance that a quadcopter can travel in the air on one full battery charge. Simply put, this is the drone's range in kilometers. Note that smaller, lighter drones tend to have a more limited flight range compared to larger, more powerful models. In the latter, it can reach 30 km or more. Also, the maximum flight distance is often influenced by weather factors and the load carried by the copter.

Maximum flight time of a quadcopter on one full battery charge. This indicator is quite approximate, since it is most often indicated for ideal conditions - in real use, the flight time may be less than stated. However, by this indicator it is quite possible to evaluate the general capabilities of the copter and compare it with other models - a longer declared flight time in practice usually means higher autonomy.

Note that for modern copters, a flight time of 20 minutes or more is considered a good indicator, and in the most “long-lasting” models it can exceed 40 minutes.

The highest speed that a quadcopter can achieve in horizontal flight. It is worth considering that in most cases this parameter is indicated for optimal operating conditions: a fully charged battery, low air temperature, minimum weight, etc. However, it is quite possible to rely on it both when choosing and when comparing different models of copters with each other.

Note that quadcopters were originally designed as stable and maneuverable aerial platforms, and not as high-speed vehicles. Therefore, you should specifically look for a fast quadcopter only in cases where the ability to quickly move from place to place is critical (for example, when the device is supposed to be used for video recording of fast-moving objects over large areas).

The speed at which the quadcopter rises up in the air or descends to the ground. Recreational, photo and video models tend to have more moderate climb/descent speeds, while professional or racing drones can rise and fall much faster. This indicator can be used to evaluate how quickly the copter can rise to a height for filming or, if necessary, avoid obstacles, and a high descent rate will be useful if the drone needs to be returned to the ground quickly and safely.

The ability of a quadcopter to maintain and maintain stable flight parameters in windy weather. In this column, it is customary to indicate the wind force in meters per second, which ensures trouble-free takeoff and landing of the drone within the permissible wind speed. Directly in flight, copters can overcome the resistance of even faster winds. But takeoffs and landings with wind strength above the designated level are fraught with unpredictable movements of the drone, loss of control and an increased risk of emergency situations.

The weight that the quadcopter is capable of carrying while performing its functions. By payload we usually mean the equipment that the aircraft carries directly without compromising flight stabilization: thermal imagers, cameras, rangefinders, release systems, etc. The higher the payload, the more diversification of missions a drone can accomplish per flight.

The type of camera installation that the quadcopter is equipped with.

- Built-in. A camera that is permanently installed on the vehicle and cannot be removed without disassembling the fuselage. This is the simplest option for tech who want to use a quadcopter for photo and video shooting or for flying with a first-person view (see “Real-time broadcast”); In addition, this camera design is considered more durable and reliable than a removable one. On the other hand, it does not make it possible to remove the camera to make the car lighter or replace it with another one that is more suitable in terms of characteristics.

- Removable. As the name suggests, such cameras are installed on detachable mounts. Thanks to this, the customer can remove or install the camera, depending on what is more important to him at the moment - the light weight of the car or the presence of an electronic “eye” on board. Note that in some models you can install not only a standard device, but also a third-party device.

- Absent. Drones that are not equipped with cameras at all fall into two main categories. The first does not involve the use of any cameras at all; As a rule, it includes inexpensive devices primarily for entertainment purposes, for which the “peephole” is just an expensive and unnecessary excess, which also increases the weight of the entire structure. The second type is models with...the ability to install a camera. It includes quite advanced copters - up to powerful professional machines capable of carrying a digital SLR. This option will be useful for tech who would like to independently select a camera to suit their needs. However, we note that the second type may have an auxiliary “eye” for live FPV broadcasts (see below); however, if such a “peephole” does not allow for taking photos/videos, it is not considered a full-fledged camera, and its presence is indicated only in additional notes. — Thermal imaging. A camera operating on the principle of a thermal imager - it detects infrared radiation from heated objects and forms a characteristic thermal image visible to the drone operator. Each color in this image corresponds to a specific temperature. A thermal imager equipped in a drone opens up possibilities not available to traditional optical cameras. So, with its help you can distinguish a person or animal against a camouflage background or in dense vegetation in an area. Thermal imaging cameras also “see” perfectly in complete darkness.

Quadcopters with a thermal imaging camera are by no means a cheap pleasure. They are used by rescuers, military, law enforcement, repairmen, hunters and fishermen. In particular, drones with a thermal imaging camera help find living people when clearing rubble, and are widely used to search for possible fires, gas leaks from pipelines, etc. In some situations, the performance of a thermal imager may be low - for example, it is not able to clearly identify an object if its temperature coincides with the background temperature (which makes it difficult to use in hot weather). In addition, the resolution and detail of the picture, even in advanced models, is quite modest. Thermal cameras in drones can be built-in or detachable.

The physical size of the photosensitive element of a camera. Measured diagonally, often indicated in fractions of an inch — for example, 1/3.2" or 1/2.3" (respectively, the second matrix will be larger than the first). Note that in such designations it is not the “ordinary” inch (2.54 cm) that is used, but the so-called "Vidiconovsky", which is less than a third and is about 17 mm. This is partly a tribute to the tradition that comes from television tubes — "vidicons" (the forerunners of modern matrices), partly — a marketing ploy that gives buyers the impression that the matrices are larger than they really are.

Anyway, for the same resolution (number of megapixels), a larger matrix means a larger size for each individual pixel; accordingly, on large matrices, more light enters each pixel, which means that such matrices have higher photosensitivity and lower noise levels, especially when shooting in low light conditions. On the other hand, increasing the diagonal of the sensor inevitably leads to an increase in its cost.

Aperture - a characteristic that determines how much the camera lens attenuates the light flux passing through it. It depends on two main characteristics - the diameter of the active aperture of the lens and the focal length - and in the classical form is written as the ratio of the first to the second, while the diameter of the effective aperture is taken as a unit: for example, 1 / 2.8. Often, when recording the characteristics of a lens, the unit is generally omitted, such a record looks, for example, like this: f / 1.8. At the same time, the larger the number in the denominator, the smaller the aperture value: f / 4.0 lenses will produce a darker image than models with f / 1.4 aperture.

Resolution of the matrix in the standard camera of the quadrocopter.

Theoretically, the higher the resolution, the sharper, more detailed image the camera can produce. However, in practice, the quality of the "picture" is highly dependent on a number of other technical features - the size of the matrix, image processing algorithms, optical properties, etc. Moreover, when increasing the resolution without increasing the size of the matrix, the image quality may drop, because. significantly increases the likelihood of noise and extraneous artifacts. And for shooting video, a large number of megapixels is not required at all: for example, to shoot Full HD (1920x1080) video, which is considered a very solid format for quadrocopters, a sensor of only 2.07 megapixels is enough.

Note that high resolution is often a sign of an advanced camera with high image quality. However, this quality is not determined by the number of megapixels, but by the characteristics of the camera and the special technologies used in it. Therefore, when choosing a quadcopter with a camera, you should look not so much at the resolution as at the class and price category of the model as a whole.

The maximum resolution of photos that the standard quadcopter camera can take. This parameter is directly related to the resolution of the matrix (see above): usually, the maximum resolution of a photo corresponds to the full resolution of the matrix. For example, for pictures of 4000x3000 pixels, a sensor of 4000 * 3000=12 megapixels is provided.

Theoretically, a higher resolution of photography allows you to achieve highly detailed photographs, with good visibility of fine details. However, as in the case of the overall resolution of the matrix, high resolution does not guarantee the same overall quality, and you should focus not only on this parameter, but also on the price category of the quadcopter and its camera.

Also note that the high resolution of the camera affects the volume of the materials being shot, for their storage and transmission, more voluminous drives and “thick” communication channels are required.

The maximum resolution and frame rate supported by the aircraft camera when shooting in HD (720p).

HD 720p is the first high-definition video standard. Notably inferior to Full HD and 4K formats in terms of performance, it nevertheless provides pretty good detail without significant demands on the camera and processing power. Therefore, HD support is found even in relatively inexpensive copters. And in high-end models, it can be provided as an addition to more advanced standards.

In drones, HD cameras typically use the classic 1280x720 resolution; other, more specific options are practically non-existent. As for the frame rate, the higher it is, the smoother the video turns out, the less movement is blurred in the frame. In general, values up to 24 fps can be called minimal, from 24 to 30 fps — medium, from 30 to 60 fps — high, and speeds over 60 fps are used mainly for slow motion HD.

The maximum resolution and frame rate supported by the aircraft camera when shooting in Full HD (1080p).

The traditional resolution of such a video is 1920x1080; this is what is most often used in drones, although occasionally there are more specific options — for example, 1280x1080. In general, this is far from the most advanced, but more than a decent high-definition video standard, such an image gives sufficient detail for most cases and looks good even on a large TV screen — 32 "and more. At the same time, achieve a high frame rate in Full HD It is relatively simple and takes up less space than higher resolution content, so Full HD shooting can be done even on aircraft that support more advanced video formats like 4K.

As for the actual frame rate, the higher it is, the smoother the video turns out, the less motion is blurred in the frame. On the other hand, the shooting speed directly affects the requirements for the power of the hardware and the volume of the finished files. In general, values up to 24 fps can be called minimal, from 24 to 30 fps — medium, from 30 to 60 fps — high, and speeds over 60 fps are used mainly for slow motion Full HD.

The maximum resolution and frame rate supported by the aircraft camera (built-in or bundled) when shooting in Quad HD.

This standard is intermediate between Full HD (see above) and UltraHD 4K (see below); in cameras of modern drones, the Quad HD frame size can be from 2560 to 2720 pixels horizontally and from 1440 to 1530 pixels vertically. In some situations, such a video turns out to be the best option: it gives better detail than Full HD, while it does not require such powerful “hardware” and capacious drives as 4K.

As for the actual frame rate, the higher it is, the smoother the video turns out, the less motion is blurred in the frame. On the other hand, the shooting speed directly affects the requirements for the power of the hardware and the volume of the finished files. In general, values up to 24 fps can be called minimal, from 24 to 30 fps — medium, from 30 to 60 fps — high. Speeds of more than 60 fps are mainly used for shooting slow-motion video, however, for a number of reasons, such a possibility is rarely provided for in the QuadHD standard: relatively simple devices would require too powerful and expensive hardware for this, and in advanced copters, where the cost of electronics not particularly important, manufacturers prefer to use slow motion at higher resolutions.

Maximum resolution and frame rate supported by the aircraft camera (built-in or bundled) when shooting in Ultra HD (4K)

UHD is a much more advanced video standard than Quad HD and even more so Full HD. Such a frame is approximately 2 times larger than a FullHD frame on each side and, accordingly, 4 times larger in terms of the total number of pixels. In this case, specific resolutions may be different; in copters, 3840x2160 and 4096x2160 are the most popular. Thus, shooting in this standard gives excellent detail; on the other hand, it puts forward rather high demands on the hardware of the camera and the amount of memory. Therefore, 4K support is an unmistakable sign of a high-end built-in camera. At the same time, we note that in modern drones you can also find more solid resolutions — see “Shooting above 4K”.

As for the actual frame rate, the higher it is, the smoother the video turns out, the less motion is blurred in the frame. On the other hand, the shooting speed directly affects the requirements for the power of the hardware and the volume of the finished files. In general, values up to 24 fps can be called minimal, from 24 to 30 fps — average, from 30 to 60 fps — above average, and a speed of 60 fps already allows us to talk about high-speed shooting UltraHD. However for full-fledged high-speed shooting, which allows you to create slow-motion videos, an even higher frame rate...is desirable, which is not yet found in copter cameras; however, modern technologies are developing rapidly, and the situation may change in the near future.

The maximum resolution and frame rate supported by the aircraft camera (built-in or bundled) when shooting at a higher standard than 4K.

Some time ago, the most solid of these standards was UltraHD 5K with resolutions from 5280x2972 to 5472x3078. However, quadcopters with support for even higher resolutions later appeared: for example, as of mid-2021, there were models capable of shooting in 8K (7680x4320). Anyway, these video standards provide a very high degree of detail, but are expensive; in addition, to fully view materials captured in such formats, screens (TVs, monitors, etc.) of the appropriate resolution are required. As for the frame rate, in this case it usually does not exceed 24 fps — this is the minimum figure required for more or less comfortable viewing; a higher shooting speed would require too expensive and “gluttonous” (in terms of power consumption) electronics.

Separately, it is worth mentioning the professional use of drones from this category. In general, high resolutions can be very useful for aerial surveillance, broadcasting of various events, professional filming of documentaries and feature videos, etc. However, in fact, for such tasks it is more convenient and reasonable to use a heavy industrial (see "Type") copter with a gimbal , on which you can install a professional "SLR" or video camera. Such equipment often provides a higher quality of shooting than the compact built-in (or complete)...“peephole” of the copter, and the user’s capabilities are wider — for example, you can use different lenses on the camera, choosing optics for the specifics of a particular situation, and then and even install different cameras on the drone. So nowadays, support for 5K or 8K can only be found in individual devices of small sizes. It makes sense to purchase such models in cases where manoeuvrability and speed are no less important to you than high-resolution video — for example, for filming air races on the same quadrocopters.

The viewing angle provided by the standard quadcopter camera; for optics with adjustable zoom, usually, the maximum value is taken into account.

The viewing angle is the angle between the lines connecting the centre of the lens to the two opposite extreme points of the visible image. Usually measured along the diagonal of the frame, but there may be exceptions. As for the specific values of this parameter, in modern copters they can range from 55 – 60 ° to 180 ° and even more. At the same time, a wider angle (ceteris paribus) allows you to simultaneously fit more space into the frame; and a narrower one covers a smaller space, however, the objects that are in the frame look larger, it is easier to see individual small details on them. So when choosing by this parameter, you should consider what is more important for you: wide coverage or an additional zoom effect.

In Time-Lapse mode, shooting is carried out at a very low frame rate (one frame every few seconds, or even minutes), due to which the effect of fast movement is achieved in the finished video (for example, a day from sunrise to sunset can fit in several minutes). This can be very convenient for fixing long-term events in which it is necessary to capture not so much the details as the general trend. For example, with the help of Time Lapse, you can shoot how the square before the concert was filled with people, or how the lighting of the landscape changed at sunrise / sunset, “stinging” these processes from a couple of hours to several minutes.

Note that the specific features of the implementation of Time Lapse in copters can be different, this point should be clarified separately.

Stabilization system built directly into the complete drone camera.

Any stabilization system is designed to compensate for vibrations and shaking, thus providing a stable image, without shaking and abrupt shifts in the camera. This feature slightly increases the cost of the device, but the quality of the video is noticeably improved. On the other hand, stabilization makes it difficult to perform complex manoeuvres, since when using it, feedback deteriorates: the change in the camera image does not quite correspond to changes in the position of the drone in space. Thus, in devices that have an acrobatic mode (see "Flight Modes"), such a system can be turned off.

Note that specifically in the camera, stabilization is most often carried out according to the electronic principle: a reserve space is allocated along the edges of the matrix, and during vibrations or shaking, the camera “pulls up” a fragment of the picture from this reserve, keeping the image in the frame motionless. This format of work somewhat reduces the useful area of the matrix, but it is inexpensive, does not affect the weight of the camera and does not complicate its design. Another option for compensating frame shifts is a mechanical gimbal stabilizer that uses a different principle of operation (see below); and some quadcopters provide both of these functions at once — this ensures maximum efficiency.

Camera gimbal equipped with mechanical stabilization system.

The mechanical gimbal stabilizer can be used in quadcopters with any type of camera (see above). The principle of operation of such a device is as follows: a system of sensors and gyroscopes monitors vibrations, vibrations and other extraneous movements of the camera and, if necessary, slightly shifts or rotates it on the suspension so that the image in the frame remains smooth, without jerks and sharp shifts. A similar function is performed by the stabilization built into the camera itself (see above), however, a stabilized gimbal has a number of advantages over it. Firstly, it allows you to use the entire area of the matrix, which further contributes to image quality. Secondly, the “picture” turns out to be quite stable even if the installed camera does not have a stabilizer. And in some modern drones, both stabilization methods are provided at once — both a suspension and a built-in camera; This slightly increases the cost, but the efficiency is maximized.

The ability to remotely control the quadcopter camera. The set of features provided by such control depends both on the type of camera (see above) and on the specific model. So, when using a third-party camera on a gimbal, control functions are most often limited to turning and tilting the lens; but for regular cameras, start and stop shooting, fixing a photo on command, changing the viewing angle, etc. can be provided.

Possibility of online video broadcasting from the quadcopter to an external device — smartphone, laptop, control panel with display, virtual reality glasses, etc.

This feature provides several benefits at once. Firstly, it greatly simplifies the control of the device, even if it is within sight; and if the copter is not visible from the ground (which happens often, especially when using heavy professional equipment), then it is very difficult to do without "eyes on board". Secondly, live broadcasting makes it possible to use a drone for real-time observations, as well as full-fledged aerial photo and video shooting; recording of footage can be carried out both on an external device that receives the broadcast, and on the aircraft’s own carrier (usually a memory card — see below).

The specific features of the live broadcast for each model should be clarified separately; however, nowadays, thanks to the development of technology, such an opportunity is available even in low-cost devices.

The presence of a slot for memory cards in the design of the quadcopter.

Usually, this function is provided in models equipped with cameras (see “Camera type”), and the cards themselves are used primarily for recording captured photos and videos. However, in some models, other data can be stored on such media — GPS tracks, flight routes, flight programs, etc. Anyway, cards are convenient, first of all, by the ability to quickly transfer data between the device and other devices that have a card reader (in particular, laptops).

It is worth noting that different devices can be designed for different standards of memory cards, and the media themselves are usually not supplied in the kit. Therefore, before choosing a card, you should clarify according to official data which type will be optimal for your model.

— Return home function. With this function, the quadcopter can automatically return to the starting point. The specific details of this feature may vary. So, some models return "home" at the user's command, others are able to do it on their own — for example, when the signal from the remote control is lost or when the battery charge is critically low; in many devices, both options are provided at once. Also note that this function is found even in models that do not have a GPS module (see "Sensors") — the copter can navigate in space in another way (by inertial sensors, by a signal from the remote control, etc.).

— Follow me mode. A mode that allows the quadcopter to constantly follow the user at a short distance — like a "personal drone". The way to implement this mode and the equipment required for it can be different: some models track the direction to the transmitter and the signal strength from it, others constantly receive data from the GPS module of a smartphone or other gadget and follow these coordinates, etc. Anyway, such a mode can be useful not only for entertainment, but also for quite practical purposes — for example, for using a quadcopter as an “air chamber”, constantly located next to the operator and at the same time not occupying hands.

— Dronie (distance). Initially, the term “dronie” refers to a selfie (photo or video) taken from a...drone. This mode is mainly intended for such tasks. And its essence lies in the fact that the copter smoothly moves away from a certain object along a given trajectory, keeping this object in the centre of the frame. The classic version of flying in Dronie mode is moving away first horizontally, then horizontally and up; however, in some models, the copter’s trajectory can be further configured. Frame management can also be carried out in different ways — from simple pointing at a certain point and ending with the selection of an object on the screen with further "smart" tracking of this object. Anyway, for all its simplicity, such a shooting technique allows you to create quite interesting videos: for example, in this way you can first capture a group of people in close-up in one video, then the beauty of the landscape around them.

— Rocket (distance up). A flight mode in which the copter smoothly rises to a predetermined altitude along a strictly vertical trajectory. Similar to the Dronie described above, it is mainly used when shooting video: first, a certain scene is shot in close-up, and as it rises, the camera covers an increasingly wider area around this scene. Usually, in Rocket mode, you can pre-set the height at which the device will stop.

— "Orbit mode" (flying in a circle). A mode that allows you to launch the copter in a circular orbit around the specified point. It is also used mainly for shooting video: in such cases, the camera remains constantly pointed at a given object, but the angle and background, due to the movement of the drone, are constantly changing. In the "orbit" settings, usually, you can set its radius, height and direction of movement, as well as the angle of the camera.

— Helix (circle in a spiral). Another mode used as an artistic technique for filming videos. In this mode, the copter, keeping a given object in the centre of the frame, moves around it in a spiral, gradually moving away and increasing its height. This allows you to get the maximum variety of angles and angles of coverage.

Note that Dronie, Rocket, Helix, and Orbit modes originally appeared as part of the proprietary QuickShot toolkit in DJI's Mavic series drones. However, later similar functions were introduced by other manufacturers, so now these names are used as common nouns.

— Flight plan(Waypoints). The ability to set a specific flight route for the quadcopter, by control points. This feature is very similar to the GPS waypoint flyby (see above), but it works differently, without the use of GPS navigation. One of the most popular options is building a route in the smartphone application through which the copter is controlled; when the programme is launched, the smartphone issues a sequence of commands corresponding to the route to the device. In general, the Waypoints mode is not as accurate as a GPS waypoint flyby and offers fewer options. Therefore, this function is mainly for entertainment purposes; if the copter has a camera, it can be useful for taking a selfie or a simple video.

— Flight by GPS points. A mode that allows you to launch a quadcopter along a specific route — by setting individual route points to the car in advance (according to GPS coordinates) and the order in which they are passed. In addition, additional settings may be provided — for example, speed and altitude on individual sections of the route. This function is similar to the Waypoints mode (see below) in many ways, but it is found mainly in mid-range and high-end devices. At the same time, the use of GPS provides higher accuracy, which allows the drone to be used for professional purposes. For example, if you set a route for shooting from the air in this way, the operator will be able to fully concentrate on working with the camera, without being distracted by controlling the copter.

— Acrobatic mode. A special mode for performing aerobatics. Note that the specific meaning of this mode may be different, depending on the level and purpose of the copter. So, in the simplest entertainment models, automatic programs are usually provided that allow you to perform certain aerobatic manoeuvres literally “at the touch of a button”. And in advanced devices in flight mode, the stabilization system is turned off, and the drone is very sensitive to operator commands; this requires high precision in control, but gives maximum control over the flight.

Additional sensors provided in the design of the quadcopter.

— Heights. A sensor that determines the flight altitude of the machine. Such sensors can use the barometric or ultrasonic principle of operation. In the first case, the height is measured by the difference in atmospheric pressure between the current point and the starting point (that is, the sensor determines the height relative to the initial level); in the second, the sensor acts similarly to sonar, sending a signal to the ground and measuring the time it takes to return. Barometric sensors are not very accurate, but they work well at high altitudes — tens and hundreds of metres; ultrasonic — on the contrary, they allow you to accurately manoeuvre at low level flight, but lose effectiveness as you climb. However, in some advanced models, both options may be provided at once. Data from the height sensor can either be used by the quadcopter “independently” (for example, when hovering or automatically returning), or transmitted to the operator to the remote control or smartphone.

— Optical. A sensor that allows the quadcopter to "see" the environment in certain directions. One of the simplest variants of such a sensor is a downward-facing camera that allows the device to “copy” the surface under which it flies. Due to this, the machine, for example, can navigate indoors, where the signal from GPS satellites does not reach. In...addition to such a chamber, "eyes" can also be provided from different sides of the machine. Note that optical sensors have certain limitations in their use — for example, they lose their effectiveness on dark, shiny or uniform (without noticeable details) surfaces, as well as at high speeds.

— GPS module. A sensor that receives signals from navigation satellites (GPS, in some models also GLONASS) and determines the current geographical coordinates of the machine. Specific ways of using position data can be different: returning home, flying by waypoints (see below), recording a flight route, etc.

— Gyroscope. A sensor that determines the direction, angle and speed of the machine's rotation along a specific axis. Modern technologies make it possible to create full-fledged three-axis gyroscopes of very compact dimensions, and it is with such modules that quadcopters are usually equipped. On the basis of gyroscopes, automatic stabilization systems usually work, returning the car to a horizontal position after a gust of wind, collision with an obstacle, etc. At the same time, such equipment affects the cost of the device, and in some cases (for example, during piloting), automatic stabilization is more of a hindrance than a useful feature. Therefore, some low-cost, as well as advanced aerobatic quadcopters, are not equipped with gyroscopes.

The location of the obstacle sensors that the quadcopter is equipped with.

Such sensors allow the drone to recognize foreign objects in the immediate vicinity in advance and avoid collisions with them; however, many models even provide the possibility of automatic avoidance of obstacles. Such equipment will definitely be useful when flying in a confined space, but it can also come in handy in open areas — they reduce the risk of bumping into wires, flying into tree branches, etc.

In terms of location, the most advanced option is full coverage, in which sensors are installed on all sides: front, rear, sides, top and bottom. However, more modest options are not uncommon. At the same time, we note that the front sensor can be provided even in models equipped with a camera and having the ability to live broadcast (see above): such a sensor usually covers the dead zone of the camera, providing, again, additional insurance against collisions.

The control method provided in the copter.

Modern drones are usually controlled by a remote control, a smartphone, or both. Here is a detailed description of each of these options:

— Remote control only. Management carried out exclusively from the complete remote control. The most common option, found in all varieties of drones — from the simplest entertainment models to high-end professional devices; and heavy commercial / industrial models (see "Type") are completely controlled exclusively in this way. Such popularity is explained by two points. Firstly, the functionality of the remote control can be almost anything — from a small device with a couple of levers and buttons to a multifunctional control unit with a screen for live broadcasts and displaying various specialized information. Thus, the equipment of the remote control can be optimally matched to the features of a particular copter. Secondly, you can install a powerful transmitter with a large range in the remote control (whereas the range of smartphones is very limited, and it also depends on the specific gadget model). Well, besides, the control panel is initially supplied with the drone (except that the batteries in some models need to be purchased separately).

— Smartphone only. Management carried out exclusively from a smartphone (or other similar gadget — for example, a tab...let) through a special application; communication is usually carried out via Wi-Fi. This option is good because almost any functionality can be provided in the control application; and the copter itself turns out to be convenient in transportation — in the sense that you do not need to carry a separate remote control with it. However, the range in such a control is very small — even under perfect conditions, it usually does not exceed 100 m, and in some models it does not even reach 50 m; and the actual communication range also strongly depends on the characteristics of the control gadget. In addition, the controls on the touch screen are not tactile, making blind control almost impossible. As a result, this option is very rare — in certain models of mini-drones and selfie-drones (see "In the direction"), for which the absence of a remote control and ease of carrying are important, and the described disadvantages are not critical.

— Remote control and smartphone. The ability to control the drone both from the remote control and from a smartphone. The features of both options are described in detail above; and their combination is found mainly in relatively simple devices, for which the shortcomings of control via a smartphone are not critical (although there are exceptions). At the same time, the main option for such copters is often control from an external gadget, and the remote control may not be included at all; This point does not hurt to clarify before buying. However, anyway, this control format gives the user the opportunity to choose the best option for a specific situation. For example, for recreational flights during a "sally" in nature, you can get by with a smartphone, and for aerobatic training, a remote control is better. So most modern quadcopters that can be controlled from a smartphone / tablet fall into this category.

The ability to control the copter with gestures.

The implementation of this function can be different. The simplest and most inexpensive option is smartphone control, when commands are given by turning and tilting the gadget. There are models where the accelerometer and gyroscope are built directly into the remote control, and you can control it with hand gestures with the remote control. Another, more expensive and original way is to recognize the position of the user's hands using the built-in camera. Such devices usually have a set of commands tied to rather specific movements. For example, by folding your fingers into a “frame”, you can turn on the burst photography mode, with a wave of your hand you can call to yourself, and the device will perceive the outstretched palm as a landing pad.

In general , gesture control provides at least additional entertainment, and in some cases can be useful from a practical point of view.

The range of the drone is the maximum distance from the control device at which a stable connection is maintained and the device remains controlled. For models that allow operation both from the remote control and from a smartphone (see "Control"), this item indicates the maximum value — usually achieved when using the remote control.

When choosing according to this indicator, note that the range is indicated for perfect conditions — within line of sight, without obstacles in the signal path and interference on the air. In reality, the control range may be somewhat lower; and when using a smartphone, it will also depend on the characteristics of a particular gadget. As for specific figures, they can vary from several tens of metres in low-cost models to 5 km or more in high-end equipment. At the same time, it should be said that the greater the range of communication, the higher its reliability in general, the better the control works with an abundance of interference and obstacles. Therefore, a powerful transmitter can be useful not only for long distances, but also for difficult conditions.

The frequency used to communicate between the aircraft and its control device (usually a remote control).

Some time ago, devices with analog control at a frequency of 27.145 MHz and 40 MHz could be found on sale. However, today these standards have practically fallen out of use and modern copter drones mainly use digital communications at a frequency of 2.4 GHz or 5.8 GHz(and some models support both of these ranges at once). This type of control has a number of advantages over analogue control. Firstly, it is less sensitive to interference: on an analog channel, a drone can mistake possible interference for a command and make an unexpected maneuver, while distortion of digital data is perceived precisely as distortion and does not affect the operation of the device. Secondly, the digital format provides high bandwidth, allowing you to even broadcast high-definition video directly from a drone. Thirdly, with this control, each “remote control-copter” pair is automatically allocated its own communication channel, and the system first checks whether it is being used by another pair of devices. Thanks to this, several devices can operate in close proximity without interfering with each other.

As for the features of specific frequency ranges, they are as follows:

- 2.4 GHz. The most popular standard in modern drones. This is due, on the one hand, to low cost (with all the advan...tages of digital control), and on the other hand, to expanded compatibility. The fact is that 2.4 GHz is the most common range of Wi-Fi modules in smartphones, tablets, etc.; so compatibility with this range allows you to easily supplement the drone with the ability to control it from an external gadget (however, this capability is not mandatory). One of the disadvantages of 2.4 GHz is also associated with the abundance of devices that use this frequency: in addition to Wi-Fi, these are Bluetooth modules, some other electronic devices, as well as most remote controls for radio-controlled equipment (not just copters). So this range is somewhat inferior to the 5.8-GHz range in terms of noise immunity; on the other hand, even with a busy broadcast, this moment is extremely rarely noticeable.

- 5.8 GHz. Further, after the 2.4 GHz described above, the development of digital standards. Allows for a longer communication range and is also more reliable, since there are significantly fewer extraneous signal sources at the 5.8 GHz frequency. In addition, the increase in frequency made it possible to increase bandwidth and effectively broadcast HD video from copters in the most advanced standards. However, some of the newest Wi-Fi standards also include support for this range, so drones in this category can also allow control from a smartphone (however, in such cases it is worth paying special attention to compatibility). The disadvantages of this option include the relatively high cost; however, thanks to the development and cheaper technology, support for 5.8 GHz can now be found even in relatively inexpensive copters.

- 2.4 GHz and 5.8 GHz. Support for both ranges described above - as a rule, with the ability to use any of them, at the user's choice. This provides additional convenience, reliability and versatility. For example, a model with two control methods (see “Control”) can use the 2.4 GHz band when working with a smartphone (which ensures a minimum of compatibility problems), and work with a remote control at 5.8 GHz (for maximum range and reliability). And drones controlled only from a remote control may even have a function such as automatically scanning ranges and selecting the least loaded one. At the same time, dual-band models are slightly more expensive than single-band ones, but the difference in price (especially with devices only at 5.8 GHz) is not particularly significant. So most modern copters capable of operating at a frequency of 5.8 GHz fall into this category.

When using specialized communication protocols, control signals between the copter and the remote control can be transmitted at special frequencies: 720 MHz, 915 (868) MHz.

The frequency of the radio channel used to transmit the video stream from the camera on board the drone to the receiving device: smartphone or tablet, control panel or pilot’s video glasses. The most common frequencies are 2.4 GHz and 5.8 GHz; video data transmission at a frequency of 1.2 GHz is less common. This parameter directly affects the quality and stability of the video signal, depending on environmental conditions, as well as accompanying interference from other devices. Thus, for receiving video from FPV drones, the most preferable frequency is 5.8 GHz, which is due to a wide selection of channels and high data transfer rates.

The presence of a mount for a smartphone or tablet on the quadcopter control panel.

This feature allows you to fix the electronic gadget in such a way that in the process of controlling the machine, its screen is constantly in front of the operator's eyes. This function is relevant primarily for live broadcasts from the device (see "Live broadcast (FPV)"). At the same time, the mount for the gadget can be found both in quadrocopters that initially have FPV mode, and in models that are not equipped with cameras (in which the possibility of live broadcasting depends on the characteristics of the installed camera). However, note that the size of the mount and its compatibility with various electronic devices may be different, so before buying it's ok to clarify what exactly can be installed on the remote control.

The presence of an information display on the quadcopter control panel.

Note that this feature should not be confused with the FPV broadcast screen (see below). The information display is usually a simple segment display capable of displaying numbers, individual letters, and, on some models, a limited set of special icons. However, even such equipment significantly expands the capabilities of the remote control and allows the operator to receive a lot of additional information: battery charge, signal level, range, flight altitude, etc. At the same time, the auxiliary screen is inexpensive and can be used even in low-cost models. And in advanced drones, it may well complement the broadcast display: separating data into different screens contributes to ease of control.

A special display that can display the image from the drone's camera in the live broadcast (FPV) mode.

The display for FPV broadcasting is usually placed on the remote control: this allows you to view the image from the camera without being distracted from the control. At the same time, the specific design of such a screen may be different: in some models it is built directly into the remote control, in others it is placed on a special mount and can be removed (or even work separately from the remote control). However, anyway, this feature means that viewing live broadcasts from the copter is available in the original configuration, for this you do not need to look for additional devices such as smartphones or tablets.

An alternative to the display in some drones is an FPV broadcast helmet. It has its advantages (see below), but the traditional screen is cheaper, moreover, it is easier and more versatile to use: so, it can be viewed without problems even with glasses, and the image can be seen by several people.

The presence of a helmet for broadcasting FPV in the package of the copter.

Such a helmet is usually a kind of mask with a built-in screen to which the image from the drone's camera is transmitted. At the same time, the mask covers the screen from all sides, which is directly in front of the operator's eyes; this provides two benefits at once. Firstly, it achieves the maximum "presence on board" effect, which not only provides additional entertainment, but also contributes to precise control. In this sense, this accessory is similar to virtual reality glasses (adjusted for the fact that the picture does not respond to head turns — it changes only when the drone's camera moves). Secondly, the screen is protected from external light, and the image on it is clearly visible regardless of the surrounding conditions — be it a sunny day, twilight or complete darkness. On the other hand, when using a helmet, the operator does not see what is happening directly next to him (more precisely, he can see these only through the camera of the copter); and for those who wear glasses, such an accessory may be inconvenient or even completely unsuitable for use. At the same time, such equipment is more expensive for everyone than the more traditional option — the FPV broadcast display (see above), installed on the remote control. So there aren't many helmet-equipped quadcopters, mostly racing models (see "Type"), for which precision control is key.

The number and type of batteries used in the quadcopter control panel.

— AA. Replaceable batteries, colloquially known as "AA batteries". They are available not only in the form of disposable batteries, but also in the form of rechargeable batteries, are produced under various brands that differ in price and quality (which provides freedom of choice), and finding such elements on the market is usually not a problem. The power and capacity of AA elements are relatively small, but in most cases they are quite enough for normal operation of the transmitter for quite a long time. Usually, modern consoles require several of these batteries; in the most high consumption this number can reach 8.

— AAA. Also known as "pinky". In fact, a smaller version of popular AA elements (see above); has the same key features, but differs in more compact dimensions and, as a result, somewhat reduced power. This option is typical for low-cost class models, with a small range of the remote control.

— 3s. This marking does not describe the size of the battery, but its operating voltage and technology. It denotes a lithium-ion or lithium-polymer battery (see "Battery type"), assembled from three cells with a standard voltage of 3.7 V each, and thereby delivering an operating voltage of 11.1 V. The advantages of such a power supply are high power and capacity, which allows you to use the remote control for a long time without recharging. At the same time, batteries of thi...s type can vary significantly in size and weight, and not every model marked 3s will be compatible with the remote control. In addition, finding a spare battery is more difficult than a set of cells of a standard size.

— Proprietary battery. Powered by an original battery that is not related to any of the options described above. Such batteries can be much more powerful than replacement cells, making them well suited even for remotes with high power consumption. Their main advantage is the difficulty with quick replacement: the design of the remote control is at best poorly suited for this, and at worst the battery is generally non-removable. Also, finding the right replacement battery can be a major hassle.

The type of motors used in the quadcopter.

Modern copter drones are traditionally equipped with electric motors (usually one for each propeller), and by type, such motors are divided into relatively simple collector and more advanced brushless ones. Here is a detailed description of each variety:

— Collector. In motors of this type, a collector is used to switch the current between the windings — a mechanical device in the form of a ring mounted on the motor shaft and divided into separate sections. The current to this ring is supplied by a pair of fixed contacts — the so-called brushes. Such a design is very simple and inexpensive, moreover, it is repaired without much difficulty. On the other hand, collector motors have a relatively low efficiency, and brush contacts wear out and fail quite quickly due to constant friction (especially with frequent operation at high speeds). Therefore, the main scope of their application are relatively simple and inexpensive quadcopters — in more advanced technology, the brushless motors described below are often used.

— Brushless. In such motors, current switching between windings is carried out using electronic circuits, without the use of moving parts. This complicates and somewhat increases the cost of the design, but it gives a number of advantages over collector units. First of all, brushless motors are more efficient and experience less wear when running at full po...wer. In addition, it is easier to adjust the actual power in them, the range of such adjustment is wider, the accuracy is higher, and the reaction to changing the settings is almost instantaneous. With all this, modern technologies make it possible to create relatively inexpensive and affordable brushless motors, the cost of which is often only a small part of the price of the entire copter. So this option is quite popular in modern drones, it can be found even among relatively inexpensive models.

The name of the engine installed in the quadcopter. Usually, knowing this name, you can easily find information about the features of the engine — both official manufacturer data and reviews from users — and determine how much you are satisfied with its characteristics. This can be very important when choosing a high-end professional model.

The number of rotors that the apparatus is equipped with.

According to this indicator, modern copters are divided into two main categories: quadrocoptershaving 4 screws, and multicopterswhere there are more than 4 screws (most often 6 or 8). There are separate models with 3 screws, but this design is not very practical, so there are very few similar devices on the market.

The most popular nowadays are models for 4 screws (quadcopters): 4 screws allow you to achieve quite a decent level of thrust and good manoeuvrability, while this arrangement is relatively simple and inexpensive. There are noticeably fewer multicopters produced — they are mostly heavy powerful devices that require both significant thrust and increased reliability (the failure of one of the propellers in such a drone is less likely to lead to a crash than in the case of a quadcopter).

The diameter of each individual quadcopter/multicopter propeller (it is usually the same for all propellers). In general, this indicator is of secondary importance: it is selected by the manufacturer in such a way as to provide features corresponding to the class of the machine. We only note that the noise level may depend on the size of the propellers: all other things being equal (the number of propellers, the number of blades, the weight of the apparatus, etc.), a propeller of a smaller diameter must rotate faster to provide the necessary thrust, and at high speeds the engines also run louder.

The ability to fold the device, making it more compact. This feature can be very useful for ease of storage and transportation — especially considering that quadcopters and multicopters (even relatively light ones) are rather bulky when unfolded due to protruding propeller shafts. Actually, it is the rods that are most often made folding : they are mounted on swivel mounts and in the “transport” position are pressed against the body. In addition to this, it may be possible to remove the screws, providing an even greater compactness.

It should be noted that additional movable connections somewhat reduce the reliability of the entire apparatus. Therefore, in heavy professional equipment, a folding design is extremely rare — ease of storage / transportation for such copters is not as important as strength and “endurance”. However, there are exceptions.

The presence of a folding chassis in the design of the quadcopter.

The classic chassis is usually folded, in the form of supports or skids; wheels for movement (see below) in this case are not considered chassis (and they usually are not foldable). Anyway, the ability to "tighten the paws" during the flight improves the aerodynamics of the device, reduces its size and gives a neat appearance. On the other hand, additional mechanisms for folding the chassis significantly affect the price and weight of the machine. Therefore, this function is found mainly among heavy professional quadcopters and multicopters. At the same time, in some models, folding can be carried out by raising and lowering the rods, at the ends of which screws are attached.

The presence in the design of the quadcopter of wheels or other devices that allow it to ride on the ground, and in some models even on walls and ceilings (due to the lifting force from the propellers).

In fact, models with wheels combine the capabilities of a quadcopter and a classic radio-controlled car. At the same time, the role of the wheels is most often purely entertaining, in fact there are extremely rare situations when they can come in handy (unless you need to “squeeze” the device into a low opening into which it would be difficult to fly — but, again, such cases are very specific ). Nevertheless, such equipment significantly expands the capabilities of the device.

Separately, we note that models with this feature may have a different design. The classic version is quite popular — 4 separate wheels. At the same time, they can have both a small and a rather large diameter; the latter has a positive effect on patency, allowing you to effectively move on uneven surfaces and overcome obstacles. In addition, there are more original types of layout — for example, a pair of large wheels, between which a quadcopter is “suspended” on an axis, or a “squirrel in a wheel” type design when the device is inside a wheel or even a lattice ball. Also, the features of the use of wheels may vary depending on the model: some quadcopters are able to switch between ride and flight modes on the go, while others need to remove and...put on the wheels manually.

The capacity of the battery supplied with the quadcopter.

Theoretically, a larger battery can provide a longer charge time. However, keep in mind that this time also depends on the power consumption of the copter — and it is determined by the power of the engines, dimensions and weight, as well as a number of other features. In addition, the actual battery capacity is determined not only by ampere-hours, but also by its nominal voltage. Therefore, only quadcopters with the same battery voltage and similar operating characteristics can be compared by amp-hours; and it is best to evaluate battery life by directly claimed flight time (see below).

The operating voltage of the battery supplied with the quadcopter. This information is not particularly important for everyday use, but may be useful in some specific cases — for example, if you need to pick up a charger or a spare battery. In addition, voltage data is needed for a correct comparison in terms of capacity (see above): recall that only batteries with the same voltage can be compared by ampere-hours, with a different number of volts, you need to use a special formula.

Battery model for which the quadcopter is designed. Most often, such a battery is supplied with the device, and data on the battery model is not needed for everyday use. At the same time, such information can be useful, for example, if the battery or "charging" to it is out of order and needs to be replaced, or if you are looking for a backup battery.

The number of batteries for the drone itself, supplied in the kit.

Most modern drones use a single battery; accordingly, the presence of several batteries in the kit usually means the ability to quickly change them. This allows you to extend the operating time without recharging the batteries: when the energy reserve is exhausted, it is enough to replace the dead battery with a fresh one. At the same time, there are quadcopters that require several batteries at once; this feature is directly indicated in the specifications (see below), and such models are usually equipped with the minimum set of batteries necessary for operation. However, there are exceptions — for example, a model for two batteries can be supplied immediately with 8 or even 10 power supplies. These nuances should be clarified separately.

Drones that require several batteries at once for normal operation — usually 2, and sometimes more (the specific number should be specified separately).

Most modern quadcopters have only one battery. Therefore, this feature is provided mainly among advanced professional devices with great battery life and range, for which one battery is no longer enough. At the same time, we note that such models may well be equipped with spare sets of batteries; see "Batteries Included" for details.

The ability to charge the quadcopter battery from a standard USB port. This charging method is convenient primarily due to the prevalence of USB: such ports are available in the vast majority of modern computers and laptops, corresponding adapters for 230 V sockets and car cigarette lighters are available, and portable power banks use USB as standard connectors. Thus, models with USB charging have very extensive connectivity options and are not limited to the "native" charger. And although the power of such charging is relatively low, however, for most copters, even this is quite enough.

the built-in cannons in modern quadcopters serve mainly an entertaining function; but the specific principle of their work and application features may be different. Thus, in battle kits (see "In the direction"), the role of "weapon" is performed by IR emitters, flashes from which are recorded by sensors on board the "enemy". In more traditional models, a spring-loaded catapult simulating the launch of rockets, a pneumatic system using plastic balls (airsoft or similar), a water "squirt" and even such an exotic system as a soap bubble generator can be used as a gun. However, anyway, the gun at least provides additional entertainment, and in some cases it can be useful for more serious tasks: aimed shooting can be a good training in the skills of precise control of the copter.

The term "protected housing" in drone copters usually refers to protection for propellers; sometimes it also covers the fuselage, but the key point is precisely the covered blades.

The specific design of such protection may be different. The traditional option is characteristic rings or arcs that cover each screw of the copter on the sides; however, there are also more exotic options — for example, a lattice "shell" that covers the entire apparatus. Anyway, in the event of a collision, the protective devices prevent the rotating blades from contacting the obstacle, protecting both the propellers themselves and the objects surrounding the copter from damage; of course, such protection is not absolute, but at least it reduces the likelihood of serious accidents. And solid rings around the screws can also increase their traction. On the other hand, the additional "kit" increases air resistance, especially when driving at high speed; therefore, in many drones (especially advanced ones), protection is made removable — primarily for flights in open areas, where there are no obstacles and the risk of collisions is minimal.

The presence of body illumination in the design of the quadcopter. Such a backlight can play the role of navigation lights, making the device clearly visible in the evening and at night and indicating which way the nose of the car is turned (the front lights are often made green, the rear lights are red). The latter can be especially useful for orientation when shooting from the air. In addition, the backlight gives the quadcopter a stylish and original appearance.

Quadcopters with non-standard design. Such machines can be made in the form of spaceships, birds and insects, monsters, flying saucers, etc. — an unusual design is limited only by the developer's imagination. The functionality of most of these devices is quite simple, and the purpose is mainly entertainment.

The material from which the body of the quadcopter is made.

In most modern models, plastic is used as the main (and most often the only) material. Plastic is easy to process, easily takes complex shapes and can be painted in any colour; in addition, its weight is quite small. It is believed that this material is not very durable; however, this is true only for relatively inexpensive quadcopters. The fact is that today there are many varieties of plastic, and high-end varieties can be extremely durable. Therefore, the strength and reliability of such cases are usually directly related to the class and price category of the quadcopter.

Other material options may include expanded polypropylene, which is lightweight with good strength; carbon fiber, which is a premium material due to its combination of lightness and high reliability; as well as metal parts used to reinforce important places subjected to high loads.

General dimensions of the device. A fairly obvious parameter; we only note that for models with a folding structure (see above), in this paragraph, the dimensions in the working (unfolded) position are given, and the dimensions in the folded form are specified separately.