Problem with jerk acceleration and PnP plugin

[jkuusama]

I'm testing grblHAL on my machine, on SKR 3 EZ board with TMC5160 drivers. I'm using third order acceleration and PnP plugin. I send G0 motion command, followed by M400. On some speed/acceleration and jerk combination, the machine spends several seconds on the last fraction of a mm of the movement. On some combination, the problem is not so apparent, but my feeling is that it is still there.

Here is a link to log where my software sends ? status request every 0.1 second after ther M400 command: log file (The "<==" is from my software to distinquish sent and received strings.) You can see that it spent a full second on the last 0.06mm. On this test, I had speed 10000mm/min, acceleration 3000mm/s^2 and jerk 30000mm/s^3.

[terjeio]

This is a known issue, I do not know if this is still worked on. Ping @Dietz0r

[Dietz0r]

We're still looking into it. But it seems to be very elusive and sadly time is very limited at the moment for hobby projects for me too. So no ETA on a fix. Sorry.