Clarification on RRF M201+M203+M566 behavior for Deltas

[Kiolia]

This is actually two questions, I think. I run a fairly zippy delta and I'm a bit unsure about the best way to set M201 / M203 / M566, because either these make no concessions for delta kinematics or the documentation is incomplete. (For context, I'd like to be able to set lower vertical move limits in the firmware vs the horizontal motion limits.) Hopefully this isn't a crazy can of worms.

First question: for deltas, do these 3 commands set the max accel / speed / jerk per physical axis (i.e., per stepper on a typical 3-stepper linear delta) or per cardinal direction?

Second question: for deltas, do these 3 commands set these limits based on the commanded effector motions (constant throughout the build volume), or the stepper/carriage motions required to achieve said motions (continuously variable throughout the build volume)?

Thanks in advance!

Also, I don't think I want to get into a discussion on how these should work for deltas, and maybe this is already a discussion I've missed, but I do think it'd be great to be able to configure limits that would prevent hitting step loss conditions at the outer print volume boundaries (where some steppers may have to outrun the head speed) without artificially limiting performance in the middle (where steppers may underrun head speed significantly).

[o_lampe]

@Kiolia I've built several Deltas in the past and never had a second thought about the implementation of these limits. I just entered individual values for X/Y and Z.
The Delta is able to move very fast in Z-direction, which is good for z-lift during travel moves and retraction. I don't understand, why you want to slow down the strongest axis?

[Kiolia]

@o_lampe Z is also a delta's effectively heaviest direction (which goes doubly for mine because it's got a flying extruder gantry that barely moves in XY), and I don't want to Z-hop (or jog) at 200k+ mm/s^2 during speed testing, at least if I can help it.

I just want to understand if the limits are imposed by direction or by motor axis and by motor or effector motion. If they are per-motor and by-motor, I think that would be best case, but this isn't detailed in the documentation and I'd like to know so I can set the limits appropriately.

[dc42]

@Kiolia for all support kinematics, the limits are applied to the tool head motion, not to individual towers or motors.

[Kiolia]

@dc42 Okay, thanks! I do think the docs could be clearer about that, although in fairness it's a nonissue for most motion systems. Appreciate the help!