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Orel 20

Low-cost BLDC motor controller for light unmanned aircraft and watercraft.

Orel 20 is an advanced controller of sensorless BLDC motors designed for use in cost sensitive applications. Its primary application domains include propulsion systems of electric unmanned aircraft and watercraft.

Orel 20 runs Sapog – an open source multiplatform BLDC controller firmware developed by Zubax Robotics.


  • Propeller drives for unmanned aerial vehicles.
  • Pump and propeller drives for unmanned watercraft.


  • Excellent dynamic characteristics.
  • Regenerative braking and active freewheeling.
  • Continuous power output up to 350 W.
  • Extremely lightweight, only 10 g.
  • Optional RPM control loop (RPM governor).
  • Embedded self diagnostic routines and health status reporting.
  • Highly configurable.
  • Low noise and low current ripple due to low ESR embedded filtering capacitors and high frequency PWM.
  • Supported interfaces:
    • CAN (UAVCAN), with optional dual redundancy.
    • UART.
    • RCPWM (analog PWM interface widely used in robotics).
  • High quality assurance:
    • Every manufactured unit undergoes a rigorous testing procedure. The testing log for each produced unit is available on the web.
    • Protection against unlicensed (counterfeit) production by means of a digital signature installed on every manufactured unit.
  • Open source firmware – Sapog (3-clause BSD license).

Related announcements and discussions

RawCommand values range

Hi! I see RawCommand for Orel 20 Sapog fw looks the same as Voltage control mode for Telega fw. And as described in reference for Sapog it supposed to be in range 0% - 100%. Actually I see it varies 0 - 8000 in my setup with Pixhawk (probably full range 0 - 10000 though). Did not found whether this …

UAVCAN ESC respond to RawCommand duration

Hi! Im doing tests on the rig with (several) Orel 20 UAVCAN ESC and motors. And see the response for RawCommand has limited duration in time. After a short spin the motor stops. So I have to send the command periodically. I think this is how it is designed. Could you please explain how can I contro…

Feeding Orel 20 ESC with 21V power supply

Hi! I see in docs 19V max power supply is stated. But want to know is it even possible to feed it with 21V (using 5S LiPo)? Because I faced with situation when 4S at maximum RPM on my octocopter makes battery voltage drop by 2 Volts itself and 0.7 Volts gets lost on wires and 1.5 Volts lost in motor…

Can Orel 20 work with Sky surfer motor

Hi, Can Orel 20 be used to drive motor 2627KV1950? Regards…

Orel 20 Max Output

Hello, Today I noticed that the maximum output I am getting from the Orel 20 is significantly lower than the maximum output I get from a traditional PWM ESC with the same battery/motor/prop setup. I am reading only 3 amps with full throttle on the Orel and over 12 amps with full throttle using a PWM…

UAV Electric Propulsion System Survey

In collaboration with the Dronecode Project (a Linux Foundation project) we are conducting a survey on the subject of UAV propulsion systems used in industrial, professional, and law enforcement applications. The results will help us better understand the challenges of electric propulsion in UAV and…

Orel 20 Transport Errors

Hello again, Now that I have been able to get the Orel 20 ESCs to stay operational, I set the uavcan_node_id for both of my ESCs along with the esc_index. However, when I connect them to my Pixhawk and monitor the Transport Stats, I get the following results: The errors count continues to increas…

Orel 20 Loops From Operatational Mode to Initialization

Hello, I recently acquired some Orel 20 ESCs and the Babel developer kit. I am having difficulty assigning Node IDs to the ESCs using the UAVCAN GUI tool. I have the Babel connected to the computer via USB and an Orel 20 ESC connected via CAN to the Babel. Ubuntu 16.04 Sapog version: 2.2.0f67ce73 …

Sapog / make firmware

Hello. I’m trying to make firmware but I got a error message: collect2: error: ld terminated with signal 11 [Segmentation fault], core dumped zubax_chibios///chibios/os/common/ports/ARMCMx/compilers/GCC/ ‘build/io.px4.sapog.elf’ command not found I think it’s caused by an GNU version. …

Gimbal motor control

Hello, is your ESCs (Orel 20 and Myxa) gimbal motor control ready?…