ESC Telemetry feedback

PX4 Autopilot Drivers & Sensors 🔧
1

Hi everyone ,
I am currently building an octo coaxial setup with the T-Motor ALPHA ESCs( w/ telemetry feedback) and I was wondering if someone already implemented or is implementing “ESC telemetry feedback” functionality.
Otherwise, I could implement and test it on my side.

Greetings,
Pedro

2

Hi
There is DShot telemetry support, but I see the ALPHA is using a different format, so that will need to be implemented.
Let me know if you need pointers on how to do it.

3

Hello Pedro,
had you problems using Alpha ESC and PX4?
We have some problems controlling the motor (T-Motor U5 KV400) and Alpha ESC (T-Motor Alpha 40 LV).
Motors don’t responde correctly to motor_test

4

Hi @davidemiccone,
no, we did not face any issues. Make sure that you have the right firmware in the ESC.
What I also noticed is that the motor test feature only gives a couple seconds pulse to the ESC. I haven’t checked the code, but to me it looks like that this is just to check if the motors are working and spinning in the right direction.

5

Hi Pedro

Are you getting any telemetry data from the ESCs? Do you have any information about the data protocol used?

6

Hi, unfortunately I didn’t have time yet to look into that. For the protocol you have to contact T-Motor.
They use a Serial Wire serial protocol at 19200BPS with 160Bytes message(all 8 ESC can “inject” in the bus the data).

7

Hi Pedro,
Is the t-motor ESC are now compatible with PX4 ?
How do you inject multiple serial telemetry on the PX4 ?
Is the px4 able to drive 8 ESC in dshot protocol ?
Thanks

8

Hi @Moi_Moi ,
if you are referring to the Dshot telemetry: YES that works. Although I have to say not 100%
If you are referring t refer to the Alpha series telemetry then: No
Yes you can have 8 DSHOT outputs if your FC supports. Mostly when doesnt have an MCU-IO.

https://docs.px4.io/master/en/peripherals/dshot.html#dshot-escs

Those for example support up to 8 Dshot outputs.
https://docs.px4.io/master/en/flight_controller/cuav_v5_plus.html
https://docs.px4.io/master/en/flight_controller/cuav_x7.html
https://docs.px4.io/master/en/flight_controller/pixhawk5x.html

9

Hi Pedro,

I’m building a project using T motor Alpha ESC with PX4. Could I ask you a question?
How could px4 get feedback signal from alpha ESC? what protocol did you use?
I have tried many methods but not succeed in that yet.

Thank you.