A few people have lost their DJI avata because of battery ejection after a crash.

No more juice, no more location of the drone... unable to find it.

Some do add buzzers to automatically beep after crash.

I have choosen another approach consisting in adding a GPS tracker to the avata.
This tracker is based on a tiny and quite cheap Ublox M8N GPS receiver. It is connected to an ESP32 microcontroller and sends the location asa Wifi beacon.

Interrestingly this wifi beacon got the homologation of French Direction of Aircraft Security (DSAC) and is the equivalent of USA "RemoteID".
This kind of beacon is not mandatory for the Avata in Europe... But it is of course allowed to add one to any drone !

A scavaged lipo from a disposable ecigarette powers the system. The wirings are very very simple:
pin 16 on ESP32 goes to GPS yellow wireTx
pin 17 on ESP32 goes to GPS green wire Rx

then black wire goes to ground
red wire goes to 3.3V

And that's it. You can add a small switch to put on/off the system.
The usb plug allows to charge the lipo pack

Everything snaps in place without any screw.

Source code is provided (see .rar file attached) and was directly derived from these links (in french)
https://www.helicomicro.com/2020/05/26/une-solution-open-source-pour-le-signalement-electronique-a-distance-a-moins-de-40-e/

The original GIthub repo is here : https://github.com/khancyr/TTGO_T_BEAM

On the receiver side, it is also easy to decode the beacon with another ESP32.
Source code is here : https://github.com/dev-fred/Decode_balise_ESP32

As a conclusion it is both a nice way to find your drone in case of a crash... and a way to identify any drone to be compliant to french regulation (for drones above 800g)

The cover is printed using PET filament made with plastic bottle : https://hackaday.io/project/185196-pullstruder-from-plastic-bottle-to-pet-filament

Prusa

i3 MK2S

No

No

.3mm

20