Footprint probing on UM3

[maht 1]

Is there a way to activate footprint probing on the UM3? i.e. active levelling probing within the area of the print instead of the entire build surface area.

I seem to remember hearing the functionality was there but just not enabled.

 

I ask because I found this interesting snippet of code in '/usr/share/griffin/griffin/machines/um3.json'

 

        "bed_level_probing": {
//            "use_footprint_probing": false, // Whether or not to just probe the footprint of the object
            "use_footprint_probing": true, // Whether or not to just probe the footprint of the object

 

As above, I changed the value to true but there didn't seem to be much effect. It didn't break the machine at least, so that's nice.

 

There was also an option for a filament runout sensor, which was a feature scrapped at the last minute for this particular machine if I recall?

 

I'm aware development for the UM3 isn't really a thing anymore but this would be a cool feature to have if the community can hack it!

 

Cheers

[gr5 2,167]

The S5 does about 25 probe points and it takes a while.  So the "footprint" probing can save quite a bit of time.

 

With the UM3 I think maybe there's only 9 probe points?  So you don't really need this feature.  The UM3 only calibrates out z offset, and x and y tilt.  The S5 creates a height map so there can be high and low spots on the glass and they are compensated for when it prints the bottom few mm.

 

Anyway I don't think "footpoint probing" makes sense for the UM3 leveling.

[maht 1]

Whether it's needed isn't the question I asked. It probably isn't needed, but I'm still curious.

What I asked is if it's possible to enable it in software - when I worked at Ultimaker I remember hearing something about the functionality being there and just being left disabled.

[Smithy 1,144]

Yes it is possible, check this posting here with the instructions:

 

[maht 1]

Ok so not exactly footprint probing but I did get multi-point bed levelling working based on the info from the thread above. Will quote here too as the other thread is mostly in German:

 

Quote

• If you feel adventurous and want to enable multi-point active leveling on the UM3 that might work a tiny bit better. It takes a lot longer though. And you know you have to enable dev mode and be somewhat handy with Linux.

If so, copy this 9066.json to the /var/lib/griffin/machines/9066.json on your printer. you can also changes other values by setting them in that file, you can just delete the file when done. you can have a look at /usr/share/griffin/griffin/machines/um3.json to see what properties there are in that "bed_level_probing" section. spacing controls the size of the grid for instance.

NOTE: this is experimental and provided as is without any warranty, etc. though you are unlikely to brick the printer by doing this you can just remove the file if you want the feature gone.

 

 

Here's how I did it (in 10 easy steps!):

 

Prerequisites: machine is connected to a network and in dev mode.

 

1. SSH into into UM3 (user: root, pw: 'ultimaker')
2. Run 'apt-get update && apt-get install -y nano' to get a simple text editor

3. Run 'nano /usr/share/griffin/griffin/machines/um3.json'

4. Change 'use_footprint_probing": false' to 'use_footprint_probing": true'

5. CTRL + X and then Y to save changes

6. Run 'mkdir -p /var/lib/griffin/machines/'

7. Run 'nano /var/lib/griffin/machines/9066.json'

8. Copy the below into it:

{
  "inherit": "/usr/share/griffin/griffin/machines/9066.json",
  "properties": {
    "machine_type_name": "Ultimaker 3",
    "bed_level_probing": {
            "probe_selection_method": "mode"
    }
  }
}

9. CTRL + X and then Y to save changes

10. Run 'reboot' and wait for the system to reboot

 

Active levelling should now be multi-point!

 

Provided without warranty, YMMV, always make a backup, etc.

 

If anyone has any ideas if footprint levelling is possible on the UM3 and how to activate it (and if it is allowed to share such info) I would be interested to hear more.

 

ok doei

Edited September 15, 2021 by mahtt

[gr5 2,167]

Keep in mind that it's easy to brick your machine when you do stuff like this.  If there are syntax errors in any json file like this one above the machine will crash before it starts up the ssh daemon.  So if you are going to do this be very cautious.  Maybe buy the olimex serial F cable (to be able to get to the root console without needing ssh) or at least make sure you have a 4MB uSD card (which can be used to unbrick).

 

Another good trick - instead of rebooting - try just restarting griffin

systemctl restart griffin.printer

systemctl status griffin.printer

 

Second command makes sure griffin started okay and if not you still have time to fix the problem.  If you restart the printer (power cycle) you may not be able to fix any typos.

[maht 1]

From Robin:

Quote

you are unlikely to brick the printer by doing this you can just remove the file if you want the feature gone.

 

UART is a good option in a pinch but it seems unlikely this will brick it. No guarantees to anyone trying this though. If all else fails, there's a recovery image here.

 

Quote

systemctl restart griffin.printer

Yeah probably easier to restart the service via systemd

Edited September 16, 2021 by mahtt

[Smithy 1,144]

A good practice in my opinion is to permanently enable the SSH daemon at startup, then the chances are very low to brick the printer when you have misplaced something in the file. 

 

For older firmware versions < v6.0 do:

systemctl enable dropbear

 

For the newer ones > v6.0:

systemctl enable ssh

 

Keep in mind that you need to disable SSH also manually if you want to turn it off. Disabling the developer mode doesn't turn it off anymore.

[CarloK 203]

On 9/15/2021 at 1:18 AM, maht said:

Is there a way to activate footprint probing on the UM3? i.e. active levelling probing within the area of the print instead of the entire build surface area.

I seem to remember hearing the functionality was there but just not enabled.

 

I ask because I found this interesting snippet of code in '/usr/share/griffin/griffin/machines/um3.json'

 

        "bed_level_probing": {
//            "use_footprint_probing": false, // Whether or not to just probe the footprint of the object
            "use_footprint_probing": true, // Whether or not to just probe the footprint of the object

 

As above, I changed the value to true but there didn't seem to be much effect. It didn't break the machine at least, so that's nice.

Footprint probing only works in combination with Active Leveling, i.e. the 'mode' setting as enabled earlier in this thread.
So, the configuration file will then look like this:
 

{
  "inherit": "/usr/share/griffin/griffin/machines/9066.json",
  "properties": {
    "machine_type_name": "Ultimaker 3",
    "bed_level_probing": {
            "use_footprint_probing": true, // Whether or not to just probe the footprint of the object
            "probe_selection_method": "mode"
    }
  }
}

Note that when you enable Active Leveling (i.e. the 'mode' setting), then in the printer's menu you can't change the probing frequency anymore (daily/weekly/etc will have no effect anymore).