Ultimaker 2 firmware bug, causes machine crash

[alexchally 0]

I have found a reproducible bug in the UM^2 firmware. After you abort a print, while the build platform is still lowering, quickly go Back to Main Menu -> Maintenance -> Advanced -> Move Material. The buildplate will begin to rise, and will not stop even after crashing into the nozzle.

I am running the latest firmware released with Cura 13.12

Here is a youtube video I uploaded of me reproducing the bug.

 

Anyone else able to reproduce this?

 

[illuminarti 18]

Yes, I've heard about it from some one else on here in the last few days - but I don't remember who. But so long as that wasn't you on another thread, then yes, at least one other person has seen this :-)

The work around is trivial, of course - don't do that :-) - but I imagine it will soon get fixed in another release as there are some other probably-related bugs that need fixing too.

 

[mnis 11]

Wow, I myself had already canceled some print jobs. So far, the described by you I have not yet happened. I also use Cura 13:12 just like you. The software bug might destroy the machine. I've played very often in the Device menu during the build platform went down after an aborted job.

Madness, the Z-axis has very much power ...

In my UM2 a fan mounting plate was not correctly formed and already led to the collision with printed objects.

The machine requires mandatory collision sensors, this I have already mentioned in an email to Sander. So far, but still no answer came.

I may seem petty, but the power switch is behind the machine has no front reset button. And as soon as I have no money for a new machine together.

Thank you for your warning video.

[mikey 0]

http://umforum.ultimaker.com/index.php?/topic/3854-u2-bed-driven-into-the-head/

Same problem

 

[illuminarti 18]

Yes, that was it! I've send a message to the support team about it as well. I think it's related to the 'lots of retraction during aborts' bug as well, so I think it will probably all get fixed in the next few days.

 

[mnis 11]

By the way, there is also no way to abort the build-plate adjustment. In an unintentional selection the entire adjustment procedure must be executed.

[illuminarti 18]

Yes, that's an annoying bug too. I'll go ahead and file a bug report on that - I've been meaning to do that for a while.

 

[illuminarti 18]

I filed two bug reports:

https://github.com/Ultimaker/Ultimaker2Marlin/issues/13

for the head crash issue, and:

https://github.com/Ultimaker/Ultimaker2Marlin/issues/14

for the bed-leveling wizard not having a way to abort.

 

[mnis 11]

Great, I'm already looking forward to the update.

The following should not be a joke, but I'm looking seriously for a future solution for better machine operation safety.

An upgrade for extremely timid natures.

A narrow pressure-sensitive construction (such as sensor film) to the fan cage around that can trigger a reset of the machine. As a result, the print head is slightly larger and this can be set in Cura. A cleverly attached additional limit switch could even be enough for the Z-axis.

Well, maybe I'm the only one who harbors such thoughts ...

[gr5 2,167]

The machine instead should be designed so that no matter what combination of crash you do, nothing is damaged.

 

[illuminarti 18]

On the UM1, there are physical limit switches on both ends of all axes, and the bed homes to z=0. This potentially prevents issues of ramming the bed into the head, if the firmware is always configured to obey the z=0 switch, and not only during homing.

On the UM2, having the homing limit switch at z-max makes it a little easier to level the bed and adjust the bed/nozzle distance dynamically, but at the risk of bed/head crashes if something goes wrong. I'm inclined to think a hybrid approach - that puts an easily adjustable z-limit switch over by the z-screw as the first of the three leveling points, might be a more failsafe way to go. (Something similar to how I redesigned thehttp://www.thingiverse.com/thing:168670to get it to work reliably).

 

[alexchally 0]

Yes, I've heard about it from some one else on here in the last few days - but I don't remember who. But so long as that wasn't you on another thread, then yes, at least one other person has seen this :smile:

The work around is trivial, of course - don't do that :smile: - but I imagine it will soon get fixed in another release as there are some other probably-related bugs that need fixing too.

 

Glad to see that I am not the only one! I totally agree that it is an easy bug to work around, I just wanted to make sure that it was noticed so that it could get fixed in the next round of updates, as no one likes that click click click sound of steppers skipping.

 

[Daid 306]

I'm on it, the "move material while still homing" is trival and fixed it.

Going to add the "abort bed adjustment" now.

 

[illuminarti 18]

Yay! Welcome back, Daid!! I hope you had a great holiday season, and some well deserved time off!!

Now give us new firmware, dammit!!! :-D

 

I'm on it, the "move material while still homing" is trival and fixed it.

Going to add the "abort bed adjustment" now.

 

[Daid 306]

Not wanting to make the same mistake twice, I've uploaded the firmware for people to test at the google group:

https://groups.google.com/forum/#!topic/ultimaker/tDKAHxe8rI0

Should fix the problems, according to my tests. But let me know if there are still issues!

 

[woofy 12]

Hi Daid,

Wow! that was fast :cool:

Just tried the new version. The retraction bug seems fixed, but only did one abort.

I like it that you now show the bed temperature on cool down, however it is displayed partly over the temperature bar. There should be plenty of space on the same line beside the nozzle temperature .

 

[mnis 11]

The little fan with the heatsink on the print head is active in all operating states of the machine. But it has probably already reported someone.

This has also been fixed in the new version?

[illuminarti 18]

It's supposed to be on all the time, I think. Probably overkill, but I don't think it really does any harm.

[mnis 11]

It is an annoying noise. My UM2 is the middle of the desk less than an arm's length away from my ears. Unfortunately, I have currently no better place for the printer. But it sucks anyway just in the quiet moments. I give the machine more food, then the noise is a minor matter ...

[illuminarti 18]

Ah. The fan on mine is totally silent. I have to look at it to see if it's on - but then I killed my first fan, and so replaced it with a slightly different model from same company; maybe that makes the difference.

 

[mnis 11]

Well then I'll prefer to wait and see until the fan starts to run roughly or so. It's time to start a new print job. Have a nice time and thank you for your support.