Tuesday 11 August 2020

Modern capabilities of quadcopters

These devices are very maneuverable and, depending on the tasks for which they are designed, have different sizes (most often small). They can work both outdoors and in hard-to-reach places: tunnels, pipes. Devices easily rise to great heights, function in places with abnormally low or high temperatures. They are excellent assistants for military purposes, as well as for engineers, rescuers, photographers, and travelers.


MikroKopter and the first quadcopter


MikroKopter is a well-known company from Germany that has become famous in the field of creating radio-controlled drones. 2006 is the date when this company invented a quadcopter in the version we know.


The first device had the following characteristics:


Atmega644 chipset and 4KB memory;

processor frequency 20 MHz;

the accuracy of the barometer is about 1 meter.


The device was equipped with 3 gyroscopes, a barometer and an accelerometer. A little later, a GPS module was added to it. The first multicopter from the German company became the basis of all such devices for pros and amateurs (for example, the DJI Mavic Air Onyx Black).

Legislative regulation of multicopter flights (on the example of strict Russian legislation)

 In the Russian Federation, a permitting procedure has been established for flights of all unmanned aerial vehicles without exception. Article 33 of the Air Code of the Russian Federation determines which UAVs are subject to registration, and which ones are subject to registration, but at present there are no legal consequences for the lack of registration / registration of unmanned aerial vehicles by citizens. For flights without a permit for the use of airspace (IVP), liability is provided under Art. 11.4 Administrative Code - for individuals a fine of up to 5,000 rubles, up to 50,000 rubles. for officials and up to 500,000 rubles. for legal entities. To obtain a permit for air travel within a populated area, an application for an air travel must be submitted in advance to the local self-government body, in which the flight plan must be indicated. At the same time, there are restrictions - in terms of time and territory (prohibited zones and flight restrictions). For example, flights near airports, military and other guarded facilities, correctional facilities are certainly prohibited, and during the 2018 FIFA World Cup, the Federal Air Transport Agency imposed restrictions on air travel over the cities of the championship from June 1 to July 17, 2018.

 

Photo or video filming using unmanned aerial vehicles is separately regulated. Shooting from the air belongs to aerial work, even when it comes to obtaining artistic photographs. In accordance with current legislation, such filming requires:

 

Permission to shoot the General Staff of the RF Armed Forces;

Permission for filming of the operational management of the headquarters of the military district, in the area of ​​responsibility of which the filmed object is located;

Permission from the territorial security agencies of the FSB;

After the filming is completed, the filmed material is transferred to the regional UFSB for declassification and subsequent use in the public domain.

 

Toy multicopters can be freely used at home.

Recently, miniature quadrocopters have appeared that fit in the palm of your hand (Walkera Ladybird, WLtoys V929, Blue Arrow nano Loop, etc.). They are practically safe (the mass of the apparatus is less than 100 g), at the same time, they allow you to get basic flight skills on a multi-rotor apparatus, since the principle of their control is no different. Quadrocopters of this size can be launched at home without risking harm to people or objects.

Flight safety of quadcopters

 

Unlike an airplane that can glide with the engine off, or a helicopter that can land using autorotation, a multicopter is completely uncontrollable when the motors or power are turned off. The quadcopter can maintain stabilization if one of the engines fails. In addition, a hexacopter or octocopter can make a soft landing with one inoperative motor, but not in all cases (for example, if at least one blade breaks, the vibration due to imbalance increases so much that the controller stops working and the device goes into an uncontrollable fall). But there are already experimental quadrocopters that can stabilize flight and land if one of the engines is lost.

 

Considering that a multicopter has a considerable mass, a rigid body and rapidly rotating propellers, its collision with people or vehicles can lead to negative consequences. Therefore, flying over people or over highways is not recommended. It is advisable to plan the flight path so that, if necessary (for example, when the battery is discharged), there is a place below for a safe landing.

 

The human factor is also important. A modern flight controller is almost as good as a desktop computer in terms of configuration complexity and the number of flight modes. Inattentive reading of the documentation, failure to perform the necessary actions (for example, calibrating the compass during setup) can lead to uncontrolled flight and loss of the device. Departure of the device beyond the range of the remote control in the absence of the GPS return mode is also one of the reasons for the loss of devices.

 

For safety reasons, some models of remotely controlled multicopters are equipped with redundant navigation and positioning systems, intelligent robotization elements that contribute to the aircraft's self-determination of obstacles on the flight route and their overflight, propeller covers or the entire aircraft, and self-return to the launch site if the control signal is lost.

Multicopter as it is

 Multicopter is an aircraft built according to a helicopter scheme, with three or more rotors.

 

A Brief History of Quadrocopters and Multicopters

 

Multi-rotor helicopters were developed in the early years of helicopter construction. One of the first quadrocopters that actually got off the ground and could stay in the air was created by Georgy Botezat and tested in 1922. The disadvantage of these devices was a complex transmission, which transmitted the rotation of one motor to several screws. The invention of the tail rotor and swashplate put an end to these efforts. New developments began in the 1950s, but things did not progress beyond prototypes.

 

Multicopters received a new birth in the XXI century, already as unmanned aerial vehicles. Due to their simplicity of construction, quadcopters are often used in amateur simulation. Multicopters are convenient for inexpensive aerial photography and filming - a bulky camera is removed from the range of propellers.

 

Operating principle

 

According to the principle of control, multicopters are:

 

* Autonomous

* Remote controlled (unmanned)

 

Multicopters have 3 or more constant pitch propellers (there is no swashplate, unlike single and twin propellers). Each propeller is driven by its own motor. Half of the propellers rotate clockwise, half counterclockwise, so the multicopter does not need a tail rotor. Multicopters are maneuvered by changing the rotational speed of the propellers. For example:

 

accelerate all screws - lifting;

speed up the screws on one side and slow down on the other - movement to the side;

accelerate the clockwise rotating screws and slow the counter-rotating in the plane.

 

The microprocessor system translates radio control commands into engine commands. To ensure stable hovering, multicopters are obligatory equipped with three gyroscopes that fix the aircraft's roll. As an auxiliary tool, sometimes, an accelerometer is also used, the data from which allows the processor to establish an absolutely horizontal position, and a pressure sensor, which allows the device to be fixed at the desired height. Also, sonar is used for automatic landing and keeping a low altitude, as well as for flying around obstacles. The use of a GPS receiver will make it possible to record the flight route in advance from a computer, as well as return the aircraft to the take-off point, in case of loss of the control radio signal, or take the flight parameters promptly or later.

 

There are also three- and five-rotor helicopters (tri- and pentacopters). One of the motors there is located on a movable platform strung on an axis, the angle of rotation of which is changed by a servo drive - this is how the apparatus rotates around its axis. Separately, it is worth noting the experimental devices: bicopters, quadcopters with variable pitch propellers, quadcopters with impeller motors, but they did not receive any distribution.

 

According to the options for placing the screws in relation to the axis of motion and depending on their direction of rotation, several types of multicopters are distinguished:

 

Modern use of multicopters

 

The modern application of multicopters is very diverse: from toys, delivery of goods, amateur means for photography and video filming to passenger and cargo vehicles and combat robots.

 

Amateur and professional multicopters use brushed and brushless electric motors and lithium polymer batteries as a power source. The screws can be installed directly on the motor shaft or through a gearbox.

 

This imposes certain restrictions on their flight characteristics: the typical mass of a multicopter is from 1 to 4 kg, with a flight time of 10 to 30 minutes (30-50 minutes for unique single copies). The lifted payload by models of medium-sized multicopters and carrying capacity is from 500 g to 2-3 kg, which allows lifting a small photo or video camera into the air (usually an action camera in cheaper models, or SLR cameras in professional ones). There are also quite large models of multicopters, with the number of rotors on the order of 6-8 (hexa and octocopters), capable of lifting a load weighing up to 20-30 kg into the air. To increase the carrying capacity, the coaxial arrangement of the bearing rotors is used, which in the case of a hexacopter, for example, gives 12 motors and 12 propellers, arranged in pairs on 6 bearing beams. The flight speed of a multicopter can be from zero (stationary hovering at a point) to 100-110 km / h. The battery power reserve allows individual multicopter models to fly up to 7-12 km, in practice, the range (the maximum distance they are able to fly away and then return to the take-off point) is usually limited by line of sight (100-200 m with manual control) or range of radio control equipment and video link. At the same time, the best examples of such equipment, using radio signal power amplifiers and a system of directional antennas, are capable of providing stable radio control and video links at distances of up to 100 km. Thus, it is the flight time that imposes the greatest limitation on the range of multicopters.

 

These limitations lead to the fact that multicopters are usually used as "short-range" devices: for amateur flights close to oneself, for photo-video filming of close objects, and so on. For comparison, unmanned aircraft with a battery of the same capacity can fly 10-15 km at a flight altitude of 1-2 km.

Friday 24 June 2016

Superior Quadcopters of 2016: copters just under $$$hundred$$$.

We talk about tiny and micro-sized copters (generally thee have the size of open hand, including the size of propellers).

1. Hubsan X4 H107L - this is an updated version of the most popular micro- beginners should purchase the option prop guard.

Banggood links - on our site both worldwide shipping and US shipping are available).

2. Dromida Verso - built in propeller guards. It has good reputation.

It’s mini-sized - about 10 square inches. And lightweight.

3. Syma X5. It’s inexpensive and very reliable. It also has good parts and knowledge availability (and it has lots of owners!). The model of a copter with an X5C designation also includes a light camera.

So, Syma X5 has recently introduced the X 11 - which is sized right in-between a micro-sized and mini-sized. We did some short review on it and really enjoyed using it. It’a like WOOOW!

So we feel comfortable suggesting it for both first and second size quadcopters.

4. WL Toys v959 (new one). This is a classic quad intensively updated with much better stabilization system. It comes with a lightweight camera. It can take video (or stills). New to quad pilots can easily remove this camera (until they will become comfortable with flying this model).

5. Dromida Ominus is another advanced quad-toy. It has very good reviews! The model is very similar to the WL Toys v636 but perhaps even better in its overall quality.

6. Syma X8C Venture copter.

This is a larger "toy" unit. It has become rather popular due to its larger payload capability and reliability. It also comes with a camera (poor quality camera). But it’s still very good for initial learning. The camera can be simply removed (and then replaced with some camera of much higher quality; for example with the RunCam or Mobius). This allows taking good aerial photos for about $150 of overall cost.

So, The larger size means this is an outdoor-only machine.

Notification. Above mentioned quads use simple cheap "brushed" MOTORS WHICH WILL NEED A REPLACEMENT (AFTER A 2-3 HOURS OF FLIGHT). Keep in mind that a couple hours of flight means 15-30 (or even more) overall flights as each flight is approximately 8-10 minutes.

So, find some quadcopter for pleasure.


Tuesday 21 June 2016

Quadcopters: some basics



Many drones aren’t for beginners. Rather they’re upgrades after you have learned the fundamentals of flying and know exactly what features you need. Simple cheap quadcopters are best drones for beginners.

We don’t suggest that tiny size quadcopters are for learning or beginners!

We currently don’t recommend some brands - Walkera, 3-D Robotics, OnagoFly. Also, we’ve had poor luck with some Parrot models in the past. However, we’re going to take a look at more models. It’s interesting to see if robustness and reliability has changed. Subsequently, be wary of all crowdfunded models.

Be sure to buy at least one extra battery and some spares you may want to have on hand (for example, motor).

<-- You can easily buy quadrocopter online here -->