The frame of the FPV drone is like a suit of armor, which is all the sensitive electronic components of the four axis aircraft. It is essential that a framework is as durable and robust as possible, while still adapting to the needs of pilots without impeding flight experience and inevitable maintenance that will follow.
Each frame has a specified dimension level, based on the longest distance from the motor to the motor, measured in millimeters, usually through a diagonal frame. A pair of motors smaller than 150 mm is classified as micro. Frames larger than 150 mm are considered Mini. When measuring an unconventional multi wing helicopter frame, such as six or three helicopters, the size will always be given by the maximum motor to motor distance.
What's in the frame of FPV drone?
Most of the micro and micro frames are cut from carbon fiber board. Carbon fiber is a kind of composite material, which is made of multi-layer interwoven carbon fiber rigidly bonded in epoxy resin matrix. The popularity of carbon fiber as a frame material is due to its low weight and high strength. It is important to note that carbon fiber is a conductive material. The average 5 "frame has arms milled from 4 mm carbon fiber and other plates 1.5-2 mm thick. In addition to carbon fiber, the second most popular frame material is high density polyethylene (HDPE). HDPE is not as strong as carbon fiber, so HDPE designs are usually heavier. HDPE frames are more flexible and tolerant than carbon fibers, allowing for improved overall durability. There are many frames that use a combination of carbon fiber and other materials, such as aluminum or 3D printing TPU (a flexible polymer) in their construction. Using these materials is a great way to increase the strength of the frame, better protect the components or simply add talent to the design.
Naming system of FPV drone framework
Four axis aircraft are the most popular design for several reasons, namely, the simplicity of the machinery, the number of motors and ESC required for flight, and their compact size. There are other forms of helicopter, although unconventional, but in some applications is perfect, even just because of their unique structure. The name of a multi wing helicopter is prefixed with a number (such as Bi, tri, quad), followed by "copter".
Frame style of FPV drone
There are many different styles of frames, all related to the posture of the arms and the size and shape of the electric carriage. Next, we will explain each frame type and a graphic example.
The real X-shape is what it sounds like, an X-shape, with a motor mounted at each end of each arm. The vertical distance between the centers of each motor is equal, thus giving the four axis vehicle the same horizontal stability on all axes.
A wide x has its arms spread out to one side. The wide x geometry is more common in freestyle frames because more central space usually requires the installation of an action camera and battery at the top of the frame.
Stretch x is a rotated wide X. Stretch x is generally favored by racers seeking more stability on the pitch axis, which improves control when four axis vehicles are racing at high speed.
The dead cat model is usually the favorite of large four axis aircraft design. The aim is to remove the propeller from the line of sight of the onboard HD camera by increasing the vertical distance between the two front engines. With the growing interest in kittens, the popularity of "dead cat" design has declined. However, there are also mini and micro four axis vehicles that continue to use the dead cat design, usually as a means of accommodating a uniquely shaped center compartment. (the dead cat is named after the pioneering design of Dutch artist Bart Jansen. Jason preserved his cat with animal specimens and turned it into an organic four axis vehicle. We hope we're joking. )
The H-type is another ancient style of four axis aircraft design. In the h-quadrilateral, the arms are placed in front of the long "bus" carriage. Recently, the h-four axis has lost its favor due to its bulky size and clumsy configuration.
HX is an updated variant of H, instead of putting the arms at the tip and tail of the carriage, a true x, wide x or stretch X configuration is applied, the most common being wide or true X.
A Z quadrilateral uses two similar base plates mounted on top of each other to produce a step geometry between the front and rear motors. Installing motors on different aircraft can improve the propeller cleaning process of four axis aircraft, because less turbulent air is directed to the rear motor during forward flight.