Xiaomi is known as the price butcher in the mobile phone and home appliances, relying on the integration of supply chain to reduce costs, but for the UAV domain, it is still valid? Through the dismantling of the way, let’s take a look at the first version of the Xiaomi MI drone (1080P version) and the similar price DJI phantom 3 standard, which is better or worse.
MI Drone Body Disassembly
The screwdriver which Xiaomi provided can only remove some of the screws, to dismantle the complete aircraft needs to be equipped with three screwdrivers: 1.5mm six inside angle screwdriver, 2mm angle screwdriver and cross screwdriver.
In order to disassemble more convenient, the positioning of the optical flow at the bottom of the fuselage auxiliary positioning module removed.
The positioning system of the optical flow of the drone is made by Beijing Feimi company. The modular design is more convenient to install and disassemble.
Optical flow positioning assist module
After removing the optical flow positioning auxiliary module, with the 1.5mm six angle screwdriver to remove the four screws and the outer side of the LED lamp screw, 2mm screwdriver to remove the remaining screws.
The circuit board visible after LED lamp shade removed. Two front LED lights is white, for the left back light is red, green light colors on the right, the corresponding color board.
You will find that the upper cover can not be opened after the demolition of the screw in the front, because in addition to the obvious screws, there are two fixed screws in the fixed position of the landing gear.
To remove these two screws, it is necessary to remove the outer shell.
You can get the whole lid down here. Demolition of the upper cover is relatively simple, then look at the internal structure.
MI Drone Internal Structure Analysis
This above design is the realization of the landing gear in the use and folding, it is an important component to maintain the position.
The voltage regulation module is installed in the four arm, in order to give this module, in the machine under the arm position is designed with cooling hole, if it rains, the rain may drain down along the cooling hole, this is very dangerous.
Voltage regulator chip is F850, the chip was launched in 2013, not advanced, but relatively high maturity.
Motor using 2212 motor, KV value of 800. This combination of electric harmonic module and motor, strong DIY ability man can try to upgrade their own. I’m just talking about the risk of refitting.
The data interface that is used to communicate with the battery is also used for encrypting ports (such as the smart battery, so it is forbidden to use the third party battery).
Two power supply contacts are designed to avoid bad contact.
GPS, the main original flight control module is in the head position, the GPS module is located at the top.
The GPS and gyro modules are securely protected, and the frame is very solid, with a soft sponge that can reduce the interference caused by vibration.
On the back of the GPS chip, the chip is covered by an electromagnetic shield. Gyroscope gyroscope module is under the GPS chip.
This is a receiver protected by a metal shield.
The control module is located under GPS chip, still be well protected.
Open the shielding cover, you can see the flight control main control chip type is ARM STM32 F407 VGT6, the series of chips by ST Microelectronics (ST), based on the advanced 32 bit microcontroller ARM kernel, its core is ARM Cortex? -M4F. The key to decide the performance level of the drone is not all processing capability of flight control chip, but the algorithm (multiple data fusion). Don’t forget, MI Drone is also more visual sensing system than the DJI Phantom 3 standard.
MI drone has internal thread buckle, in order to secure with adhesive sealant.
Remote Controller dismantling
The screws of remote shell are hidden, four screws were located in the lower part and the top of remote control handle.
The joystick of the remote controller is not on the same side with the main board, and the front and back cover of the remote controller can be separated after remove the control line.
Little difference with ordinary rocker of aeromodelling remote control, but also an increase of miniature bearings, detail is in place.
The remote control main board, receiver, graphics transmission module, battery and other functional modules are fixed on the rear shell.
The main board and vision transmission module of the remote control are installed on both sides of the mobile phone support cabin and are connected by a long pin. The specific model of the remote control chip is ARM STM32 F103 RBT6.
The maximum transmission distance of 1080P version is 1000 meters (to be tested).
Mobile phone support cabin
MI Drone Opened family portrait
DJI Phantom 3 Standard
DJI uses an integrated main board design, basically all the sensors and chips are placed in the middle of the main board. The benefits of doing so is to minimize the amount of space occupied by the fuselage, but the maintenance costs are relatively high, if a broken part of the board to replace the whole.
The protection of the gyro is particularly good, can be described as the degree of exaggeration – plastic box is a sponge, sponge inside a metal box, open the metal box is the gyroscope.
Voltage regulator chip of DJI Phantom 3 is F330.
Can be seen from the dismantling of the comparison chart, due to ID (Industrial Design) difference, the overall layout of the DJI Phantom 3 s and MI Drone is also different.
MI Drone central fuselage almost all left to the battery, so the circuit can only be placed in the nose, it is difficult to achieve the project, but it can reduce the thickness of the fuselage, easy portability, and low maintenance cost.
The body of DJI Phantom 3 s has more space, so that all the circuit (including power transfer) are integrated together, and the battery and pilt are placed at the bottom of the fuselage . Benefits are more conducive to wiring, clean and good maintenance. Disadvantage is the high cost of maintenance, the increase in the thickness of the body is not easy to carry.
From the internal and the overall design, DJI is obviously more sophisticated. But Xiaomi is not a cottage, although the separation of the circuit, but the design of each module is also very elegant, the material is also very substantial. You can imagine Xiaomi team really do painstaking products retreat practice over the last 1 years.