TinyG limit switch reaction time

From the original Synthetos forum (2011–2025)

Started by Karl Lew on in TinyG Support. 2 replies, last activity Apr 18, 2013.

#

My TinyG is happily wired in to FirePick and is humming along quite nicely:

http://www.youtube.com/watch?v=eWZ145UbPq8

I have a question about limit switch reaction time. As you can see in the homing video, the drive belt whips and slackens when the head contacts the limit switch at the homing velocity, which is 1/30 of the maximum velocity. If I increase the homing velocity, the head derails off the MakerSlide because it's basically crashing into the limit switch.

I have NO limit switches. If I switch to NC limit switches, will I see improved reaction time from TinyG since it may not need to debounce as long?

#

Alden, thank you for your most excellent advice. It was indeed the jerk homing parameter:
http://youtu.be/QYS0nsMFFH0
The jerk homing is now set at 64x jerk maximum, which makes TinyG "react faster" to prevent head crash into homing stop. Doing this also permitted faster search velocity.

Staff #

Just to be clear Alden, on the OpenPNP forum posted this response.  Thanks for the follow up Karl.  You rock.

It's expected that the search velocity needs to be tuned for the setup, and should be significantly slower than the max velocity. Have you tried using a higher jerk for homing? The homing jerk is independently settable for this purpose. The jerk can actually be set high enough that you lose steps on the decel. This is OK as you are in a homing operation. You would never want to run it this high in actual operation. Please let me know if this gives you more headroom.

Alden

This topic is from the original forum (April 2013). Your reply starts a new discussion linked to it.

Reply

Different problem? Ask a new question

Back to TinyG Support or latest activity.