TEST: XIAOMI FIMI A3

[Drone News]

INTRODUCTION

After the super popular Xiaomi FIMI 4K, here is the Xiaomi FIMI A3, probably the cheapest 1080p stabilized video plateform in the market. Dislike its big brother, we have no more a WiFi based digital hi-res FPV system but an old-fashion efficient analog system in order to save costs. But the main advantage of this machine is probably to offer a real 2-axis mechanical video stabilization overlayed with an Electronic one for the third yaw axis. The machine comes in RTF edition where the radio command integrates also a FPV monitor and a builtin DVR to record your favorite flight/FPV sessions. Everything for around 250USD…. so clearly in the same price segment of the Hubsan H501S or the MJX Bugs 3/6. Xiaomi FIMI is known to offer good quality for their quadcopters, let’s check if this entry model will still continue this traduction.

BOX CONTENT

Like any Xiaomi model, the box is optmized in size to reduce post shipping fees. The box is suprizingly small …. but every thing is here inside

+ 1 x Xiaomi Fimi A3
+ 1 x Transmitter (with a builtin 1S LiPo battery)
+ 1 x Charger
+ 1 x Power unit
+ 1 x 3S balancer plug cable
+ 1 x USB to microUSB cable
+ 2 x Spare props (1 CW, 1 CCW)
+ 1 x Instruction manual (English)

First small deception…. we have a very basic LiPo charger… like the ones included with basic toysquadcopter. It uses the 3S JST balancer plug connexions. Two LED lights are present: one when the charger is powered and another when to show charging activity. We will talk about this charger later…

Second negative point is the absence of a camera dome casing protecting the gimbal…. Of course you can design easily one but…. out of the box, it’s really missing….

OVERVIEW

The machine is built with the same quality plastic of the Xiaomi 4K, a soft and flexible one with high quality. The design is relatively flat, a 323mm machine in term of dimension. Unfortunatly…. arms can’t be folded so it will require more space for transportation. Probably one of the most negative point.

-FRONT VIEW
No obstacle avoidance sensor…. Was predictable with such low-entry model. The gimbal is a micro compact one where the integration of the camera is included in the tilt axis. Stabilize a super lightweight camera module is really challenging. In general only DJI managed this job with the Spark & the mavic.

-SIDE VIEW
No visible USB/microUSB port anywhere. The design is very wind profiled with curvy shapes.

Each arms ends with some lights. Rear ones indicates more the battery status.

As usual, when red lights start to flash fast, it means the battery becomes low.

-REAR VIEW

Battery connector with redondant pins for a 3S system

Hidden and protected by the battery, the microSD port and the microUSB to update both the flight controller and camera firmwares

No risk to loose the microSD card during a crash. Smart location.

-UPPER VIEW

A small GPS/glonass dome….

-BOTTOM VIEW
The power button is located button. As the former model, to turn on/off the machine you will have first to short press on this button, release it then long press and hold it diring 3s. Notice the absence of any VPU system to increase potentially even better the altitude stabilization… especially indoors where the GPS signal is absent. In this situation, it mean the stabilization is done only via the builtin barometer

One really positive element is the presence of a DIY port when you can plug some future third party accesories. They are controlled via PWM connexion. The rear right button is dedicaced to trigger this port…. Great

-WEIGHT

Just a little bit less than 560g ….. not so so bad for a 350mm video plateform.

Motors and props

Some 1805 motors branded by FIMI directly directly. Notice that CCW motors are painted with an orange line in order to match the corresponding prop directly

3mm shaft section but with a spring installed for the new prop lock system

The prop installation takes just a fraction of second…. It’s a brilliant solution !!!! I really like it… Very smart. Just push the prop, turn a quater of tour and you are ready to flight !!!!

Battery

Of course we have a proprietary battery, a 2000mAh 3S model…. but not smart…. I mean there is no specific auto-storage capacity. So if you plan to park this machine for a couple of weeks, you will have to discharge by yourself each cell at 50%.

By reading carrefully the sticker, we can read 12.75V…. so clearly is not a simple LiPo with a max of 4.2V per cell but a model more close to a LiHV battery up to 4.35V per cell. The problem is the actual charger can’t reach 4.35V per cell …. Si in practice you won’t charge the battery at full capacity.

One way to overcome the non-possibility to fully charge the battery is first of course to use a charger with LiHV capacity but you will need also the cable compatible with. For this, you can mod the provided one by soldering a mean lead connector.

As soon as the cable is built, it’s interesting to notice that each cell don’t have the same internal impedance. In fact the cell 3 shows a higher value, linked with a builtin resistance in the circuit.

In practice, as soon as you start the charge cycle, the cells 3 show +0.1V more versus cells 1 & 2.

Camera module

With a FOV of 80 degrees, the camera sensor is a 1/3.2″ CMOS model. The camera is fully integrated with the tilt axis to gain weight and place.

On the pitch angle can be controlled by the left rear button

micro Dampening balls installed

The video recording is splitted into 1Gb files of 2min24. In 1080p@30fps, the datarate is about 60Mbit/s…. Not so bad at all.

Here is a raw sample of the A3

If the video is not super sharp, I don’t suffer too much of blurred edges as reported from some earlier users. In any case, with default settings, the white and the blue color are oversaturated. Luckely, a bunch of settings are available via the radio. The sound is not recorded.

Transmitter

One of the most positive element of the bundle, i.e. the radio transmitter including both a 2.4G radio link to control the machine and a 5.8G builtin VRX collecting the CVBS video flux transmitted by the quad. The quality of the transmitter is really good with nice and precise metal sticks. Internally the antennas are attached to the main PCB/modules via iPX connectors. So it can be super easy to replace default antennas for some higher gain ones. Via the radio settings, it’s possible to change the 5.8G frequency. It means that this channel is transmitted in the radio protocol.

If the quality build is really good, the screen got a brillant surface and in presence of strong daylights, it’s hard to see all details. Clearly, the radio would deserve to have a sunshade installed or in the worst case a system to welcome one. It’s not the case ….

In the right part, this tiny joystick allows you to enter into the main radio/quad/camera settings or to access directly for smart flight/DVR functions.

A microUSB port is here to charge the builtin battery, to update the RC firmware. Nearby a microSD slot to record your FPV sessions.

As any GPS based machine, the compass calibration is a must to do procedure. Two clock-wise mouvements are required. They are clearly depicted by the animation in the radio.

When you boot the radio, you have centralization of all pre-flight informations.

The FPV signal is recorded in D1 NTSC format in 720×480@30fps.

Here is a raw sample recorded via the builtin DVR. It’s more dark than the direct signal which can be recorded by an external goggles/FPV screen. Probably linked with the extra OSD informations overlayed.

As for the HD recordings, the FPV recording is splitted into 3min files. The sound is recorded and as you can see, the GPS informations are stored. A pretty nice option to localize your machine if you loose it during a long range flight. A small artefact can be noticed with the DVR files. You can often observed at end of each file, a ghost video fragment of a former recording. It happens even if you format the card….. Need probably a full in depth formating.

UNBOXING, ANALYSIS AND DEMO FLIGHT

Even if my FIMI A3 comes from a second batch and with almost up to date firmwares, I decided to install all the new firmwares available at: https://www.fimi.com/. Firmwares update procedure works flawless.

With the new firmware, a new “cinematic” flight mode where all rates are limited as well as the gimbal one. I guess also, EIS is also applied over the two-mechanically stabilized axis. This new mode is ideal to shoot super smooth videos.

This first video shows the content of the bundle, the role of each radio-transmitters buttons and probably first important mod to do, the DIY charger cable from the one provided in the bundle. Important point, if you plan to flight far, you will have to extend the max flight distance setting. Notice also if you plan to fly this machine in europe, you must in theory turns the machine into CE mode instead of FCC (default setting).

When associated with a charger with a LiHV program, as you can see, the voltage of the cell 3 is about +0.1v higher than the two other cells. At then end of the balance program, each cells will converge to 4.35V.

After a local compass calibration, the machine in GPS mode is able to take off from 9 satellites. Push lower inner both stick to arm the machine. From 1m high, the altitude hold of the machine is really accurate !!!! Impressive. What I really like is the silence of the A3… Beyond 20m, you can’t event acoustically notice the quadcopter.

Clearly the the video stabilization system is doing a great job. It’s almost without any vibrations….. really this is the most impressive point of this machine. In term of video quality, with the last camera firmware, the color rendition staturates a bit white and blue color. Thanks to all the camera setting available (especially EV), you can fix that. The video is good…. not ultra sharp (a bit blurred for background scene) but really not bad at all. Small details, when you land the machine, Recordings are automatically stoppped. To enjoy a full control and FPV range, you must install antennas vertically. Out of the box the machine can achieve 1km very easily. Important point: when the FPV signal is too low, the builtin remote FPV screen becomes blue. It’s really annoying. It may be fixed with a firmware update, not for the radio but for the LCD controller…. probably with a programmer stick. So not an easy procedure. Via pushing the small dial up, you can have a quick access to all the smart flight modes. When engaged, you can discard the selected flight mode by pressing the home button. The RTH works fine and had a precision about 2m from the take off location. The orbit mode can be controlled via the pitch & roll axis of the right stick. The rolls controls the velocity of the circling, the pitch the radius. No possibility to tune the yaw with the mode. The Cinematic mode smooth everything….. So fly slowly and the video results will be really good. The gimbal control is also slowed down with this mide. The fixed wing mode limit also the pitch & roll axis. Be aware, you have a lot of inertia associated with….. It’s hard to stop the machine quicly in this mode.
The follow-me uses the second builtin GPS module integrated in the radio. In general such kind of follow-me are not super accurate but here it’s not the case…. It’s working well…. not as good as a visual tracking mode but it’s really efficient.
For the DVR recording, as mentioned before, the end of each DVR files can present some ghost segments from previous recorded files. Don’t know if it can be fixed with a new RC firmware update. A full and slow format helps a lot of to reduce these artefacts. When I like, DVR saves also important informations like the GPS coordinates of the machine. A little disapointing element is the flight duration, about 20min even when the battery is charged in LIHV mode. A bit far from the 25min advertised.

CONCLUSIONS

The Xiaomi FIMI A3 is a good machine. When sold around 250USD, there is no real other competitors because this is the sole machine with a gimbal system while other offer in the best case only a EIS stabilization. It kills for example the (2 years old) Hubsan H501S or any last MJX Bug products. The FIMI A3 is stable, accurate, reliable without toilet bowling effect. The quality build is also very good. Of course there is no 1080p@60fps or 4K resolutions, but the 1080p@30 fps recordings are already not bad. We can maybe regret the non-possibility to fold the machine for an easier transportation. When balancing all positives points with the negatives, the FIMI A3 can be easily recommanded.

PROS

+ Cheap stabilized video plateform
+ Almost perfect video stabilization
+ Good 1080p@30fps videos
+ Full RTF solution
+ Good quality build
+ Great FPV & control range
+ Easy prop installation
+ OSD informations (GPS coordinates) saved with the FPV link via the builtin DVR
+ A lot of advanced flight modes
+ 22min of flight duration ? => More about 20-21min
+ Silent machine
+ DIY port for 3th party accesories
+ Relatively cheap

CONS

– Not foldable
– No gimbal dome for transportation
– Need a DIY mod to charge fully the Li-HV battery
– Need a charger with the Li-HV program
– Cell 3 of the battery got higher internal resitance
– Videos/photos not sharp => blurred on borders
– Color rendition (too much blue and white)
– No 1080p@60fps
– Blue Screen when the FPV signal is lost/low
– Brillant FPV screen=>Need a sunshade
– Inportant OSD informations (GPS coordinates) are added by the RC not natively on the drone=>External VRX won’t be able to receive GPS informations. Only AVout export them but you will use the radio builtin VRX
– Potential “Ghost video fragments” at the end of each FPV DVR files

This quadcopter have been courtesy provided by Banggood in order to make a fair and not biased review. I would like to thank them for this attitude.
You can find it actually for 299USD at https://www.banggood.com/Xiaomi-FIMI-A3-5_8G-1KM-FPV-With-2-axis-Gimbal-1080P-Camera-25mins-Flight-Time-GPS-RC-Drone-Quadcopter-RTF-p-1368969.html

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