Xiaomi Mi Drone 4K

The Xiaomi Drone 4K is on the market for some time now so why a such late review you may ask ? Well it’s simple, people when have new tech and review it they usually are optimistic and give out biased opinions and they don’t have a reliability factor taken into account. I will share my opinions and I will tell you some less known stuff and mostly the “cons” that no one is telling you.

Versions

It’s a highly asked question of what version of drone to choose as it’s sold in options: Chinese, USA, etc. The single difference is the bundle as the China version comes with propeller guards while the other versions come without them but it includes a WiFi dongle of which we are going to talk about later. There is also now a China version and a “China + prop guard” version, the first one has the WiFi dongle while the second one misses it.

The “localization” of the drone also makes a lot of rumors about charging it and supported voltages. The is only one type of charge which accepts 100-240V and supports both 50 and 60Hz systems, the only difference is the power cord which may not fit your outlet. You can use a simple prong converter that is found online for ~ 0.99$.

The Smart Battery

The battery is also subjected to a million of suppositions about the button color, the capacity, the voltage, how to charge it, etc. I will tell you: there is only a single type of battery, the button color is just cosmetic and the battery will get a firmware update from the Mi Drone App ! The specs are also just the following:

Cell voltage: 4.35 V/cell – chemistry Li-Hv (Lithium Polymer High Voltage)
Number of cells: 4
Voltage: max. 17.4V (battery full), nominal: 15.2V
Charging & balancing: Internal balance charger, standard charger current: 2.9A
Capacity: 5100mAh

Fast charge & Multi Charge

The Li-Hv cells as like LiPo cells are safe to be charged with no detriment on life performance up to 1C rating that means 1 times the capacity rating which for the Mi Drone battery is 5100mAh * 1x = 5100mA or 5.1A, so this battery can be charged as fast as 5.1A without damage or reducing lifespan. The power supply / charger only needs to provide a constant 17.4V and the internal circuit from the battery will balance the cells and shut down charging when 100% full. The internal battery circuit does not limit the charge current so with a charger like the one above you can charge at 4.5A thus decreasing spent time.

The motors on the Mi Drone 4K are different than the ones from the 1080p version and although they are upgraded they are not perfect. Main issues are noise and squealing from the ball bearings, in most cases they do not cause any problem, but at 12$ a motor it would not hurt to get a spare one. Notice they are CW and CCW variations so choose the one needed or get a pair. Another issue is the quick release system, it creates a small play between the prop and the motor shaft making additional vibrations, a DIY quick fix is to add a small piece of clear thin tape on the the motor shaft to reduce the play. My recommendation is also to get some extra props as they are more brittle than normal plastic ones and they will shatter easy on impacts.

Another **issue is the gimbal, as a lot of people lost it in flight and that problem was actually from the locking mechanism which was not secured properly. It won’t hurt to observe the locking and and making sure it’s properly installed. The same thing happens to the battery which if not fully insert – it can be ejected due to vibrations.

What is the WiFi dongle and what does it do ? That is simple, to use the drone you need a smart device (tablet or phone) which needs to be connected to the transmitter (not the drone) and this can be done in two ways, with a USB cable like on DJI Phantom 3/4 & Mavic series or with a small dongle which will replace the cable and take advantage of the 2.4Gh WiFi by creating a local SSID to which your phone will connect. Advantages are more hanging wire and no influence on drone range, the disadvantages are a slightly bigger image delay and less stability in phone / app utilization. A word of warning here if you fly together with other Mi Drones, all the dongles have the same default SSID and the same password and your phone can connect to another drone transmitter creating big issues ! Either change the setting or use the cable. Also the local SSID can be jammed by home WiFi and local networks so again use with caution.

What is this hump, what is ATTI, VPU and GPS modes.

The Mi Drone has an array of extra sensors and camera which form the VPU – visual positioning unit and it’s further assisted by a sonar. This sensors will help the drone keep the position even with no GPS as long as it’s close to the ground to “see it” and to “hear it” meaning the sonar will measure the height while the VPU camera will detect drifting and will apply correction. At bigger heights when the VPU can no longer detect changes the GPS is needed to get a 3D fix and keep the drone locked into position. The ATTI mode is not for beginners and disables VPU and GPS and the drone will only keep height using a BARO sensor, this will make it drift with the wind. The ATTI mode is a back-up solution if the compass sensor fails in flight which will render GPS useless or highly unstable.

1080p vs 4K

There are a lot of discussion also about the two models the 1080p and the 4K version, while a lot of users will tell that you don’t need 4K or that it’s the same with another camera, the you need to find out that this is not true and that the 4K version is actually a 2nd revision of the Mi Drone 1080p and that happens to have upgraded and improved: motors, flight controller, IMU, compass and power distribution board ! As you see the whole drone, beside the battery is changed so you would definitely want the 4K version !

Should I buy it or not, is it reliable ?

Absolutely YES, for its price and performance the Mi Drone 4K is a great drone with a great camera, the reliability is also good while the performance is on average better than a Phantom 3 Pro / SE, the camera can do 4K@30fps but will also do 2.7K@60fps and even 1080p@120fps making smooth and great slow motion videos. The real flight time is also better than the DJI Phantom 3 series and the battery drain is more constant and predictable.

Last but not least the Mi Drone 4K has another card of it’s sleeve, a handheld grip for the drone camera that it will turn it into a portable handheld 3 axis stabilized gimbal for just ~70$ further reducing the overall user cost and making it a better option for travel as not needing an extra gimbal and camera for “land” footage.

Videos and guides 

Unboxing, inspection, first startup, configuration, firmware update and full menu walkthrough

An extreme maiden flight with high winds

Availability, parts and accessories

Mi Drone 4K
5 in 1 charger
GearBest  Banggood

Propeller set
GearBest  Banggood

Replacement motors
GearBest  Banggood

Fimi handheld gimbal
GearBest  Banggood

 Mi drone backpack

GearBest
WiFi Dongle
GearBest  Banggood