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The microcontroller on the Larson Scanner is rated for an absolute maximum of 5.5 V. Any more than this can permanently damage it, and potentially create a hazardous situation. Chips have been known to overheat or even explode if exposed to too much voltage. And, the resistors in the circuit are configured to give a safe level of current at 3 V.
Resistors alone cannot reduce the voltage from the battery in such a way that there is a guaranteed safe voltage level. (This is because as the current drawn goes to zero, so does the voltage across the resistor– effectively, the full 9 V goes across the microcontroller at turn-on time.)The *safe* way to run the Larson Scanner would be to give it its own 3 V power supply– from a separate pair of AA or AAA batteries, or a CR2032 coin cell if need be. This can be very compact, if that is the issue.Another method would be to use a set of diodes to drop the voltage. A small signal diode (such as a 1N914) drops about 0.7 V. You could use 8 of them in series to drop the 9 V to about 3.4 V. Or, you could use three red LEDs, each of which drops about 1.8 V, to drop 5.4 V, giving you about 3.6 V. This would also have the side effect of giving a few more red LEDs for the costume.I’m not sure exactly what is wrong with the file (or perhaps with Inkscape, or perhaps with our software and how we handle documents that have had a unit transformation), but here is how to fix it: Start with the Inkscape template for letter size (File > Templates > Letter) and then import your SVG into that file, using File > Import.
For the future, I would recommend that you update your SVG generating script to use that template (or even your new SVG created by the method above), and fill in the center part with the actual data that you want to use.
Also, the behavior that you are seeing is essentially what one might expect from a large scaling error– it’s trying to travel far outside the mechanical limits of the machine, and the “software limit switches” are limiting its range of movement, and hence leaving it in a corner. With your permission, I’ll keep your file around as a test case, and hopefully we can handle scaling errors more gracefully in the future.
Hi Beau,
Lots of people have had luck plotting SVGs– however yours seems to be a special case. I am looking into it, and also following up with the e-mail that you sent to us separately. I will answer you in both places.While it doesn’t say so directly, this error actually indicates that there has been a communication error with the machine. Most often, we have seen this kind of thing when someone is using either (1) an extra long USB cable (2) an extra thin USB cable, or (3) a USB extension cord, but there are some other things that might cause this. If you are using a cable like one of those, you might try using the one that came in the box. If you are using the cable that came in the box, you might try a different cable (if one is handy), just to rule out that it isn’t our cable that is defective.
If the machine is behaving itself otherwise, we do have a newer version of the software that you might try, which catches and can “ride over” some of these nonfatal bumps. (The software is available on github, but if you e-mail us through our contact form, we can e-mail the full bundle to you, and that’s likely easier.)[Follow-up comment by Shel from the other thread, reposted by me — I mangled this thread while splitting it from the other.]
When I want to pause, I’m usually in a real hurry to make it happen. That’s why I even put a fluorescent dot on the switch …just to gain me a fraction of a second in finding it. Finding and precisely pushing the switch on the EBB board is simply an exercise in frustration for these old eyes.In other words, I hope B0 can continue its present duties. 8^)
Here’s a picture of my switch setup, it’s really handy. I used some InstaMorph plastic for the saddle mount (friction fit, so its position is moveable if need be), and E6000 to glue the switch to the saddle.
I guess that’s a good note to add here– that B0 can be used as a pause button. (We are currently planning the next EBB version, and that is helpful feedback.)
You can potentially use the pen-up/pen-down events in the EggBot control scripts to turn a laser on and off through the EBB.
What I’d suggest is changing the definition of the pen-up and the pen-down commands, to turn the laser off and on, respectively.
The EBB command set documentation is here: http://evil-mad.github.io/EggBot/ebb.html
One of the “fine print” things there is that there a number of “UBW” commands supported, which are documented here:
http://www.schmalzhaus.com/UBW/Doc/FirmwareDDocumentation_v145.htmlYou’ll want to use the “PO” command from that set, for example “PO,B,0,0” to take pin B0 low, or “PO,B,0,1” to take pin B0 high (I have not tested these commands while writing this — just reading from the docs). Pins B0 and B2 would be particularly good choices, since they are not otherwise used on the EggBot/WaterColorBot/AxiDraw software.
We do not presently have a LOGO interpreter. It was a topic under discussion some time ago, but we realized that modern Scratch-like block-based programming languages (which kids are learning today instead of LOGO) are great for making LOGO-like turtle graphics.
Two possible approaches if you would like to try that out:1. Use BeetleBlocks, and save your output turtle graphics as SVG. Some examples of using that with the WaterColorBot (one of our other pen plotters) can be found here:2. Use Scratch or (preferably) Snap, and print directly.AxiDraw can be used with RoboPaint in its “remote print” mode to accept turtle graphics commands through the API. We have examples in Scratch and Snap, available here: https://github.com/evil-mad/WaterColorBlocksThese are typically phrased as “WaterColorBot” examples, but will work perfectly well on the AxiDraw too, so long as you have configured RoboPaint to AxiDraw mode.Hi Shel,
Yes, that will work (for a short time, as you note). We used one, for example, on our Kraftwerk-inspired tie project: http://www.evilmadscientist.com/2011/a-new-kraftwerk-inspired-led-tie-kit/That video shows a few different things. The word “AxiDraw” is spelled out with a regular font, which consists of an outline that the machine follows, if you do watch the video closely. As it says in the manual, “All standard fonts are outline fonts […]. This means that when you do convert it to a path, it produces a hollow outline that your pen can follow.” This is normal and correct behavior.
The other text is written in single-stroke text (not regular fonts), specially designed for use with plotters. Again, as it says in the manual, you can use the Hershey Text utility to create single stroke text, and additional single-stroke fonts (of various types) are described in the URL given there, http://imajeenyus.com/computer/20150110_single_line_fonts/index.shtmlCurrently, the print driver is built into Inkscape. Depending on your workflow, you may want to create and edit your notes in Inkscape, or create and edit them in MS Word. In the latter case, you can export your text and think of Inkscape as the “Page setup” screen for your printing (positioning it on the page, filling text if using block letters, etc). The advantage of doing your design work in Inkscape is that it’s a little faster, and can let you (for example) create templates for doing multiple similar notes.
I would also note that no driver installation is needed for the EBB under Windows 10– Windows will automatically detect and install the proper driver, even if you don’t run ours.
The link seems to work. And yes, those screws that you’ve drawn the arrows to are the same ones that I was referring to. However, there shouldn’t be any plastic parts there– that should be metal on metal on metal.
Can you please not sure what you mean about these looking different from the user guide? I don’t see any difference there from what’s pictured in the guide.We have generally not had a problem with those screws loosening. However, if they have come loose then be sure to (1) fully remove the pen clip before trying to tighten them, and (2) use the short side of the 3/32 hex L-wrench to tighten them. If they persist in loosening, you might try a drop of threadlocker if you have access to it, or adding a small dot of glue to the side of the screw head (once attached) to prevent it from turning. You might also try tightening the two screws one at a time (tightening only one of them — leaving the other loose) to see if perhaps one of the screws isn’t really tightening at all.
