Kalle Hyvönen of DGK Electronics has created a new Inkscape extension that might be handy for all of us robot builders:
I developed an extension for Inkscape which can create optical rotary encoder discs in any size/number of segments. It currently supports single and two-track (quadrature) encoders but I’m going to add support for gray encoded discs as well.
Link: Inkscape extension for creating optical rotary encoder discs
(via Inkscape on G+)
We have written before about the the Silicon Valley Electronics Flea Market, one of our favorite places to go treasure hunting. At this weekend’s flea, we came across a cache of beautiful old diodes, including some in rather unusual packages.
Continue reading Interesting Diodes from the Electronics Flea Market
One of the most useful tools in our shop is our laser cutter— or more formally, our low power carbon dioxide laser cutting and engraving machine. We use it for all kinds of mechanical prototyping, cutting parts out of wood and acrylic, and even some production parts, like the cases for our clock kits, the custom cloth numbers on our d12 and d20 bag kits, and the pen arm on the Eggbot kit.
And while this has been a fantastic and reliable machine for the last several years, eventually the moment that we had dreaded arrived. Our laser power began to droop, and it started getting harder and harder to cut through the materials that we regularly work with. A visit from a technician confirmed that the power had fallen significantly, and that we needed a new tube. The replacement process is actually managed as a swap: The factory sends us a new laser cartridge, and we send them back our old one.
But on the bright side, we get to take a close peek at the laser hardware. It is interesting to note that many commercial laser engravers have user serviceable parts inside. Even the laser cartridge itself can be replaced by relative novices. The smaller (closer, dirtier) of the two cartridges shown above is our old one, and the new (well, refurbished) cartridge came with installation instructions and mounting bracket adapter to compensate for the change in shape from the previous cartridge to the newer one.
We recently came across this instructable by rleyland on hacking our ISP Shield for Arduino for use with ATtiny45 and ATtiny85 microcontrollers. These are occasionally handy little AVRs, and we’ve previously written about using our ATtiny2313 target boards for the ATtiny25/45/85 family here.
This weekend we will be visiting the Los Angeles area and we’re planning a meetup at Los Angeles Hackerspace Null Space Labs. This will be informal, but we’ll be bringing along a few of our little projects to show off.
The fine folks at Null Space Labs have generously offered to host the event, which is scheduled for Saturday evening, the 23rd of June, from 8-11 PM.
Null Space Labs is located at 1015 South Main Street, Los Angeles, CA (Google Map). Please see their about page for parking details.
In case of overflow, or other last-minute changes on Saturday, please check our twitter feed for updates. We’ll hope to see you there!
These two real-world examples of CNC Art made using StippleGen 2 come from Bruce Shapiro, who created them at The Mill. Above, a stippled portrait of Einstein is laser cut into cardboard, using light stipples on a dark background. Below, a paper mask was applied to a piece of wood, v-carved with a CNC router, spray painted, and then the mask was removed. This time, a light background with dark stipples was used.
The same source image was used for both, although the image is mirrored for the wooden portrait.
It’s great to see some examples of what StippleGen can do out there in the real world. If you have any examples of your own to share, we’d love to see them in the Evil Mad Science Auxiliary pool on flickr.
Photos by Bruce Shapiro used with permission.
Venus is just now passing between the earth and the sun, and so we stepped outside to take a look. We brought out a pair of binoculars to use to project the image of the sun onto a piece of paper on the ground. We also took a solar viewing film, but it turns out that the binoculars were a great way to see it as a group. These pictures were taken just after Venus crossed over the edge, and the speck you can see at the edge is much clearer if you click through to the large size on flickr. Over there, you may also be able to make out a couple of sunspots that we were also able to see with the binoculars, but not with the viewing film. Remember, don’t look directly at the sun without proper safety equipment! (See our earlier post for more details on viewing techniques.) The transit is still underway, so you still have a chance to get outside and see it!
Update: Part II, with a slightly different method.
To get a slightly better view, we used a simple telescope mounted to a tripod.
Aside: This is the Galileoscope, a high-quality, very low cost telescope for $50 (or as little $25 in classroom packs). It’s designed to let you discover everything that Galileo could see with his telescope, including craters on the moon and the moons of Jupiter, albeit with modern optics that dramatically improve image clarity.
Now, the one thing that you really don’t want to do with a telescope is directly look at the sun through it. (It’s bad enough to stare into the sun; it’s much worse to concentrate the light into a tiny spot. That’s a good way to start fires, not view the Transit!)
What you can do is to project the light from the telescope onto a piece of paper or matte-white plastic. Adjust the focus until the edges are sharp and— poof! —suddenly, you can see the sunspots.
And the image quality isn’t half bad. This picture was taken right at the “peak” of the Transit, when Venus was as far into the disk of the sun as it went. Our image on the screen is about two inches (five cm) across, and it’s easy to make out the features.
Most stunning of all is the incredibly rare opportunity to see a planet in the sky not just as a “point of light” but to see it for what it is: another planet just like ours, slowly orbiting around the same sun.
