Adding a display/Untethered use

A forum dedicated to the stock LulzBot Mini 3D Printer
John Mc
Posts: 347
Joined: Wed Dec 23, 2015 5:16 pm
Location: Vermont

Re: Adding a display/Untethered use

Post by John Mc » Fri Oct 06, 2017 9:16 am

If you are using the Raspberry Pi and don't always have a WiFi network available, there is a great solution to this. Kenneth Jiang wrote a great set of directions for setting up the Pi and OctoPrint for just your situation. On boot, the Pi will look for known WiFi networks to log on to. If no known WiFi networks are found, the Pi will automatically set itself up as a WiFi Hotspot. You can then access OctoPrint from any computer by just logging on to the Pi's hotspot. No need to add a touch screen and no need to run the GUI on the PI (which consumes a lot of resources, slowing down the Pi).

Here are the instructions for the Automatic Pi WiFi HotSpot. The first part of the article is just help in setting up OctoPrint for normal WiFi networking - you can skip that part if you've already got it working on an existing WiFi network. Scroll down about 1/3 of the page to find the section titled "Turns your Pi into a Wi-Fi hotspot, automatically" and follow the directions there.

I've used this when transporting a 3D printer among different classrooms. It works flawlessly. When we're at a school where I've already put in the WiFi log-on info, it connects automatically. If I'm in a place where there is no WiFi (or the school where the IT guy refused to give us the WiFi password), the Pi just sets up it's own Hotspot, with no intervention from me.

NOTE: the autohotspot is NOT dependent on OctoPi to work. It should work on any Raspian-Jessie installation.

EDIT - the WiFi hotspot instructions have been confirmed to work on OctoPi 0.13 and 0.14 (which were based on Raspian-Jessie-lite). It does not work on Raspian-stretch based systems. Stretch has changed some of the networking files and directories. OctoPi 0.15, the version currently in development, is based on Stretch, so the WiFi hotspot feature will not work on it. The author is aware of the problem. Hopefully, he'll do an update when OctoPi 0.15 is released.
Last edited by John Mc on Tue Jan 16, 2018 9:37 am, edited 5 times in total.

kcchen_00
Posts: 1562
Joined: Thu Feb 19, 2015 12:42 am

Re: Adding a display/Untethered use

Post by kcchen_00 » Tue Oct 10, 2017 12:43 am

John Mc wrote:
Fri Oct 06, 2017 9:16 am

Here are the instructions for the Automatic Pi WiFi HotSpot.
Nice find! While I don't travel with my Taz, I can see how this could come in handy for transportable setups.

Thanks for sharing!

John Mc
Posts: 347
Joined: Wed Dec 23, 2015 5:16 pm
Location: Vermont

Re: Adding a display/Untethered use

Post by John Mc » Tue Oct 10, 2017 8:42 am

kcchen_00 wrote:
Tue Oct 10, 2017 12:43 am
Nice find! While I don't travel with my Taz, I can see how this could come in handy for transportable setups.

Thanks for sharing!
I helped Kenneth debug and improve it (mostly by being good at breaking things... I don't claim to be good at programming).

I requested Kenneth's help because the IT guy at the elementary school system where I was volunteering would not give the WiFi password to anyone except for use on the school's own computers. He didn't want "unauthorized" devices on his network. The Pi hotspot got us by until one of the kids managed to get the network password. I've also used it when doing a 3D Printing demonstration at another school.
Last edited by John Mc on Tue Jan 16, 2018 9:35 am, edited 1 time in total.

jhackt
Posts: 8
Joined: Wed Sep 20, 2017 12:29 pm

Re: Adding a display/Untethered use

Post by jhackt » Tue Oct 17, 2017 7:32 am

Thanks John Mc! This is really interesting, I'll get into that immediately :)

jhackt
Posts: 8
Joined: Wed Sep 20, 2017 12:29 pm

Re: Adding a display/Untethered use

Post by jhackt » Tue Jan 16, 2018 4:50 am

Brent.I wrote:
Fri Sep 22, 2017 11:32 am
We have done some experimenting with this, and an add-on is something that is currently in development. You can find more information on it here: https://code.alephobjects.com/source/gyrfalcon/


Hi Brent, in your recent youtube-video from CES i spotted some "smart controller" like displays on the lulzbot-minis on the showfloor - are those the ones you were talking about?

I'm still very much interested in adding a controller - we are still on tethered use for our education-machines due to various reasons :(

Brent.I
Aleph Objects | LulzBot
Posts: 356
Joined: Mon Jan 20, 2014 8:21 am

Re: Adding a display/Untethered use

Post by Brent.I » Tue Jan 16, 2018 7:59 am

jhackt wrote:
Tue Oct 17, 2017 7:32 am
are those the ones you were talking about?
Yup, those are the ones! We announced them in late Q4 of 2017, and hope to have them available soon. Sign up for our newsletter, and you will get an update when new products become available: https://www.lulzbot.com/content/newsletter-signup

John Mc
Posts: 347
Joined: Wed Dec 23, 2015 5:16 pm
Location: Vermont

Re: Adding a display/Untethered use

Post by John Mc » Tue Jan 16, 2018 9:01 am

jhackt -

Did you ever try using the Pi running Octoprint as a Hotspot?

At one point, I had the Pi/OctoPrint set up to access it right on a screen we attached to the Pi (an old VGA monitor scavenged from one of the school's defunct desktops with an HDMI to VGA adapter). I ended up going back to running the Pi as a Hotspot and having them access it via OctoPrint's browser interface. It meant not as many kids bumping around the printer and the Pi, so less chance of something getting disconnected. We also hooked up a cheap USB camera to the Pi (Logitech C270) so the kids could check on their print via a web browser.

Newer versions of Cura (and I believe some other slicers) will let you send gcode directly to OctoPrint for printing, so you can bypass the OctoPI browser interface completely, if you want. I've done that at home. I haven't decided whether to do it at school. The interface for the newer versions of Cura can be complex. We may decide to stick with doing our slicing on Cura included with OctoPrint. With the addition of the "Full-featured slicer" plugin, it will handle 95% of the things the kids print without having to slice on their ancient laptops.

NOTE: I edited the post where I described the Hotspot feature earlier in this thread to include a warning that the Hotspot feature does not currently work on systems based on Raspian-Stretch (like OctoPi 0.15 now in development)

John Mc
Posts: 347
Joined: Wed Dec 23, 2015 5:16 pm
Location: Vermont

Re: Adding a display/Untethered use

Post by John Mc » Tue Jan 16, 2018 9:44 am

Brent.I wrote:
Tue Jan 16, 2018 7:59 am
jhackt wrote:
Tue Oct 17, 2017 7:32 am
are those the ones you were talking about?
Yup, those are the ones! We announced them in late Q4 of 2017, and hope to have them available soon. Sign up for our newsletter, and you will get an update when new products become available: https://www.lulzbot.com/content/newsletter-signup
Brent - I missed the announcement. I received the Nov. 21, 2017 newsletter, and one on Jan 9, 2018, but never saw anything about the new Mini controller. I'll nose around and look for that announcement. I'm excited about that and the new modular print bed. (I actually bought a complete spare print bed to use in the school where I volunteer - those 5th & 6th graders were pretty tough n the PEI surface when removing prints, until I made some adjustments to make removal easier. I'll probably sell my spare and go for the modular. Being able to do a PEI replacement without having to disconnect the bed completley will be helpful.)

jhackt
Posts: 8
Joined: Wed Sep 20, 2017 12:29 pm

Re: Adding a display/Untethered use

Post by jhackt » Mon Jan 29, 2018 8:17 am

John Mc wrote:
Tue Jan 16, 2018 9:01 am
jhackt -

Did you ever try using the Pi running Octoprint as a Hotspot?

Not yet - I've just been too busy to look any further into the whole pi-situation and kept schlepping two extra laptops for the two Minis. Now, I'll just wait for the magical gyrfalcon to show up. But I'll still investigate further into running a printer-farm on octoprint or repetier because I'm currently planing a setup for rapid small part runs based on 4-8 ender 2 or tronxy X1 - style cheapo-printers. But thats a story for another forum...

Post Reply