Individual propeller control

[luisgb]

Can the propellers in any of the products be controlled individually? If I want to command either the desired thrust or the desired speed of each propeller individually, can I do it?

[Alex Kushleyev]

@luisgb , all of ModalAI ESCs can be controlled via UART using two modes

• power : command 0-100% power, which controls the average duty cycle for that motor
• RPM : (requires calibration for the motor + propeller type): controls rpm directly

Commands to the ESC are sent via UART and normally that UART port is connected to VOXL2 UART, which is mapped directly to the DSP. The DSP is where most of PX4 runs.

If you are looking for the easiest integration / testing, you can connect the ESC directly the VOXL2 CPU (using non-DSP UARTs) and use either python or c++ code to interface to the ESC (or similarly from a Linux Desktop / laptop).

It is also possible to communicate with the ESC while the ESC is connected to the DSP UART. This is how the voxl-esc tools work on VOXL2 (while PX4 is not running). This works by bridging the connection between the DSP and CPU and accessing the DSP UART from the CPU. However, this path has extra delay and is not recommended for any real-time feedback control applications.

If you provide more information about your use case, I can suggest the best path.

Alex