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Also: Awesome project, looks great! We have a hyperball machine, ourselves. ;)
I don’t know how much available power supply capacity you have in your machine– I suspect that it’s high enough that another lightbulb worth of power (enough to run several more kits) would not be a problem. The limits that I suggested were based on just using as much power as a single light bulb. The conversion circuit itself should be able to run 10+ Flickery Flame kits.
Implemented, just for you. :)I’ve just pushed an update to the EggBot software that will allow it to skip pen-up movements of zero (well, less than one motor step of) distance. This is something that we previously implemented on the AxiDraw software, and it was easy to bring it over.You’ll need to manually update your EggBot software to 2.7.5. You can get it by downloading the ZIP file at https://github.com/evil-mad/EggBot , and copying the contents of its “inkscape_driver” directory into your Inkscape extensions directory.(On a Mac, this is: /Applications/Inkscape.app/Contents/Resources/share/inkscape/extensionsOn Windows, this is: [your program files directory]Inkscapeshareextensions )Depending on which version of the extensions you have, you might need to also install the latest version of the “plotink” helper routines, too. You can download these in the ZIP file at: https://github.com/evil-mad/plotink and copy them into your extensions directory, replacing the old ones.(Now, back in Inkscape, one can also potentially combine the different objects into a single path, and then join the relevant points, however, this is hit and miss.)These attribution type questions — especially the names — are a little tricky. With the Jenna Sue example, “free for commercial or personal use” does not necessarily include derivatives, whereas the OFL fonts do explicitly allow derivatives. However, they also allow the license to require a name change (etc.). That kind of information *should* be packaged with the font somewhere– perhaps in the font file itself… and it would be good to figure that out before publishing any derivatives. (I haven’t looked inside the font files themselves.) If there is not any obvious location where that can be found, we’re likely in the clear to publish these.
I particularly do like the Sacramento. Bilbo, too. A fantastic source of these SIL OFL fonts (not sure if this is where you’re getting them) is Google Fonts, when you filter by “Handwriting”. Clicking through that list, I thought that the following (in addition to the ones that you already created) might be good candidates: Mrs Saint Delafield, League Script, Bad Script, Tangerine, Alex Brush, Parisienne, Delius, Qwigley, and Felipa
Probably the best way to move forward would be to add these directly to the Hershey text extension… a possible path forward _from there_ would be that we could get this updated into a future version of Inkscape itself. :) (And for that reason, we probably don’t want to label any of them as EggBot specific.)
One other consideration, which you’re probably thinking about: When possible, it is best to try and match the locations where cursive-type letters begin and end. I have an experimental optimization that I’ve been trying out, which skips the pen raise-and-lower if the pen travel distance is zero (really, below a fixed, small threshold). This makes much neater characters when the pen doesn’t have to lift between them.
It’s a tricky call what the best way to move forward on that software is– a Hershey-style font editor is a really neat idea, but I’m not sure that it’s best in Inkscape, or elsewhere– perhaps as a processing sketch that can run within a browser? There are font editing capabilities built into Inkscape now; it might be worth looking at how that process works.
Yes, that should work well. You might consider also looking at our clear-lens yellow flickering LEDs, which are particularly good for this purpose, since they project more of a beam than the diffused LEDs in the flickery flame kits.
Computer fans are not particularly tolerant of unexpected voltage inputs– a 5 V DC computer fan wants steady 5 V DC. Using a regulator is an OK idea, but it might be better to give it 6 V DC (4 C or D cells), with a load resistor and/or diode to drop the voltage down to 5.These look really great! If we start with fonts that are covered under the SIL Open Font License — Architect’s Daughter, Sacramento, and Allura are — then it should be acceptable to create and publish derivative fonts of those, so long as we comply with the license terms. One asterisk is that the font designer can require that the name of derivatives is changed… and it may be kinder to do so whether or not it is required.
After some digging…. Looks like the img tag works OK, if the URL is the actual image.
http://i.imgur.com/7wmraYb.png, nothttp://i.imgur.com/7wmraYb
Yes, it’s a good idea.
I’ve often thought about trying to create more fonts in the Hershey format… and there are precedents for creating font derivatives on your own computer (for your personal use). Having an editor that would let you create new Hershey Fonts would be pretty awesome indeed. :)4.5 V DC is enough to run _one_ LED if it is blue, white, or “pure” green. It’s enough to run two red or yellow LEDs in series.
Ah! Here you go: http://www.evilmadscientist.com/2012/resistors-for-leds/
The flickering LEDs cannot be used in series, nor directly driven by AC. Think of the processor in each LED as being a bit like a computer– when you remove power (whether that’s by switching it with AC or by putting it in series with an LED that blinks off its power), it reboots, and never gets to run its flickering program.
However, there are some good ways to get the basic result that you are after. For example, one flickering can be used in series with one or more non-flickering LEDs, and will cause all of the LEDs in that series-driven set to flicker together. With several flickering LEDs, each in series with several more LEDs, you can make a wide and striking effect.
You can read more about this see an example application, here: http://www.evilmadscientist.com/2012/flicker-leds/As far as the AC goes, I would recommend that you build a basic AC to DC converter, such as the “Full-wave Rectifier with Smoothing Capacitor” described here: http://www.electronics-tutorials.ws/diode/diode_6.html
This circuit can be made as simply as four diodes plus a capacitor, or with an off-the-shelf bridge rectifier (e.g., Jameco Part number 178001, $0.29) and a capacitor (say Jameco part number 93761). 6.3 V AC will give you roughly 4.5 V DC with this circuit– enough voltage to power two LEDs in series, or one in series with a resistor.
You could also run flickery flame kits directly from that 4.5 V DC. If your machine’s output circuit was rated for 0.25 A, then you would have enough power to run three Flickery Flame kits off of that one output. (Figure ~80 mA each typical draw.)
One note is that our white Flickery Flame kits are designed to run from 4.5 V DC, but the red/yellow Flickery Flame kits are designed to run from 3 V. So, three off-the-shelf white kits should work fine, but if you were using the red/yellow kits, you would want to substitute in a different resistor value, perhaps 150 ohms or so.
Awesome– glad to hear it. And, neat enclosure! Does the button switch settings?
The cutoff value is the setting for the sensitivity adjustment– there is not any additional default level of filtering beyond setting a threshold on the rate of change of the infrared signal that is detected. Some other things that you can play with in the code, perhaps, include the amount of time spent sampling (num_acd_readings, as you noted), and the constants in the filteredReading function — which set the number of samples acquired and averaged to determine the slope. Playing with those values might require you to adjust the cutoff values as well.
Depending on the exact nature of the stray triggers that you are seeing, averaging for a longer period of time before determining the slope might help, or it might not.
Another physical modification that you might consider would be to add a sleeve around the IR sensors and/or emitters, that helps to narrow their field of view. You could use a piece of black heat-shrink tubing, even not-shrunk– just like a short, black section of a drinking draw.
Tempered glass can be tricky, because some types admit less IR light than regular glass. The “active” sensing part of the sensing tends to be diminished, since the IR light that is emitted has to make two round trips through the glass.
What we would usually recommend — if at all possible — is to add some supplemental light sources outside of the glass, to allow it to be stimulated by passive sensing as well. Typically, that would be something like a halogen lamp or near-infrared illuminator (the kind used by security cameras; usually LED-based and invisible), pointing at the table top.For a programming approach, yes adjust the cutoff values.
