Using ODrive S1 Connected via CAN with CoreXY

Ryosuke Saito

I am considering using brushless motors instead of stepper motors to power my CoreXY machine. I am planning to use the ODrive S1 driver.

Until now, I thought that the only way to connect with ODrive was by using STEP/DIR, but I was excited to discover in the following issue that dc42 mentioned "communicating with ODrives via the secondary CAN bus on the MB6HC and MB6XD has been implemented."
https://github.com/Duet3D/RepRapFirmware/issues/219
However, the documentation seems to imply that it is intended for "Hangprinter kinematics."
Can an ODrive connected via CAN be used with kinematics other than Hangprinter, such as CoreXY?

With STEP/DIR, when increasing the resolution per revolution, there are cases where the speed is insufficient even if the ODrive's STEP pulse frequency limit (50kHz) is reached.
(For example, when using a 20T pulley with a GT2 belt, achieving a minimum movement amount of less than 10µm takes about 3 seconds to move 1mm).

tobbelobb created this issue in Duet3D/RepRapFirmware

closed Talk to ODrives via UART #219

jay_s_uk

@Ryosuke-Saito I believe the CAN implementation is purely for configuring them and step/direction etc still need to be connected

o_lampe

@Ryosuke-Saito In my experience with other brushless step/dir interfaces it is the other way round:
A stepper with 200/400 polepairs versus a BLDC motor with eg. 10 or 15 PP needs way more pulses per revolution.
The good thing about FOC is, you can fake a much higher resolution than there is. The microstepping works here, too.
So I configured my gimbal motor drivers the same way as the steppers and they work flawlessly as extruder drive.