The 2025-04-07 release of the CMCopter-4.5 branch of the open-source ArduCopter-4.5.7 autopilot became our latest official stable firmware for outdoor drones.
The precompiled binary of the latest firmware is available at the Skybrush website for a wide range of officially supported autopilots.
The new release contains the following feature updates that also enhance the reliability and safety of drone shows.
Bubble geofence support #
A global take-home message of recent drone show accidents is that it is very important to have a very reliable automated geofencing system that acts as early as possible in case of emergencies to avoid lateral damage. Current solutions all around the world define a global geofence, which possibly reacts to drone misbehaviour too late.
Our brand new solution for this requirement became the new “bubble geofence” feature, which builds upon our earlier show drift warning system: the bubble geofence follows the desired drone show trajectory and triggers a general geofence breach event when the actual position of a drone deviates from the desired trajectory too much during a show. This results in adaptive geofencing that acts as soon as it is physically possible and does not let the drones wander away and/or speed up too much when they cannot follow their trajectories for any reason.
The new bubble geofence can be enabled with the new SHOW_BFENCE_EN parameter and can be configured with 4 additional parameters to have proper spatial deviation thresholds, timeout and geofence breach action.
The bubble geofence is an experimental feature, we appreciate any feedback!
RSSI feedback based on received RTK corrections #
We have implemented a new solution for having an informative RSSI feedback on both the primary WiFi and secondary radio channels: we count the received RTCM messages on the drone side and send the counters back in status packets to Skybrush Server. The server can now be configured to display these counters as RSSI information.
WARNING: You need to download the latest Skybrush Server - 2.25.1 at the time of writing - and configure its MAVLink extension to use this feature!
No undesired yawing during takeoff any more #
We have corrected a bug related to undesired yawing during takeoff. Takeoffs are now completely smooth. All you need to do is concentrate on your show and enjoy.
SpeedybeeF4v4 is officially supported #
We have finally added official support for SpeedybeeF4v4. Thanks for all community feedback on the usage of this flight controller!
New LED type support: servo with limits #
The SHOW_LED0_TYPE parameter got a new possible value: “Servo with limits” (13). This is an enhanced version of the standard “Servo” (6) mode, with possibility to give explicit thresholds for minimum and maximum PWM values in the output.
Feature credits: @mwd-sean. Thank you!
Fine tune LED brightness on the ground #
The SHOW_PRE_LIGHTS parameter now interprets values greater than 3 as pure percentage. This way you can fine-tune LED brightness on the ground. New behaviour is of course backward compatible, old values still exist (0 = 0%, 1 = 25%, 2 = 50%, 3= 100%).
Feature credits: @mwd-sean. Thank you!
Threshold minimum brightness of LEDs #
The new SHOW_LED0_MINBRI parameter lets you setup a minimum brightness below which your LEDs will turn pure black. This helps you avoid possible low-brightness flickering of your LED module.
Feature credits: @mwd-sean. Thank you!
Providing feedback #
The ArduCopter-based Skybrush firmware is fully open-source. If you like it, use it, and wish to continue using it, please consider a one-time or recurring donation, or buy professional license for Skybrush Live. We will use your support to develop Skybrush further and to be able to keep it as open as possible.
Please also give us feedback on our Discord server or directly in the GitHub issue trackers of our related open-source repositories: ArduCopter, Skybrush Server or Skybrush Live.
Thank you!