Ever work on a project and find yourself needing a spring? Ever go to
the hardware store looking for one, and have to compromise because the
offerings are so slim?
At the next Open House (Sept 28th) we will have materials for
making simple coil springs. If you have a project in need of a spring,
or if you’d just like to check it out, come on by. We’re certainly no experts and you wouldn’t want to mass produce them this way, but adding
a new tool to the toolbox is always fun and may come in handy one day.
If you have a project in mind, try to bring as much information as you
can so we can take a stab at making you something that will work. We
can do extension-, compression-, and torsion springs. Note that the
final heat treating process takes about 2 hours so I will probably do
that part at home and bring the completed springs in to the following
Open House.
Home-made springs (torsion, compression, and extension) and some examples of their uses: mini catapult, spring scale, and wear-compensating anti-backlash nut
There were so many wonderful things it was hard for me to pick a favorite. That is, until I hit the Ultimaker Booth. Ultimaker is another open source 3D printer offshoot of the RepRap Project. Erik de Brijn, Martijn Elserman, and the rest of their team have been hard at work perfecting v1 of the Ultimaker (and now Ultimaker+). The quality of this machine continues to amaze me (I’ve seen a previous beta version in person at Botacon). New this year, when mixed up with the newest firmware Marlin (which was recently ported to 3D FDM printers and is based on GRBL, the same firmware codebase picked to run Lasersaur), the Ultimaker is able to get insanely high resolution prints. You can get the Marlin firmware for RAMPS and RepRap from HERE on Github.
Erik gave me one of the high res Yoda prints (Thanks Erik!) which I put under the microscope last week. You can see with the scale bar… we have 162 pixels = 1 mm. The average layer height in that pic is around 12 pixels, or 0.074 mm (That is 74 microns). And that orangey low res looking thing on the left? That’s not a print… that’s my finger. Click the image to see in higher detail!
We had a solid, but uncrowded open house last night, complete with all the usual unstructured goings-on and a side order of semi-structured activities.
Two "Bacterial Cellulose Bioreactors"
Adam Korshid, UArts Industrial Design alum and local “kombuchaneer” stopped by to share some Acetobacter Xylinum cultures and give Pez’s microbial cellulose operation a re-boot. We were joined by local artist and 915 building neighbor Ann Saintpeter. We mixed up two 44″ by 18″ trays with a special “blanco cellulose” medium in the form of sugar, yeast and apple-cider vinegar. To prepare the medium we used a rigorous, proven methodology that is generally referred to in the relevant scientific literature as TLAR (“that looks about right”) and verified our efforts using the TTAR2 methodology (“that tastes about right, too”) — as if we know what constitutes A. Xylinum’s standards of delciousness. Then we turned the bacteria loose in the pond to do their thing. We’ll deliver the resulting paper to Ann to see if it has a place in her art.
Chris and Brendan pop the hood on an Epson 7700 in need of TLC
Ann also donated an Epson 7700 that needs some TLC. We spent some time working on it, and learned a thing or two. For example, we learned how to reset the counter on the maintenance tank (yay, $60 unnecessary expense avoided) and also tried to clear the black ink line by “replacing” the cartridge (boo, $50 unnecessary expense incurred when the printer apparently rejected our “spent” ink cartridge for good). We’ll re-flash those ink cartridges and show the printer who’s boss — and the printer is well worth the effort involved in rescue.
Dan and some-guy-whose-name-i-didnt-catch were off in a corner working on developing something using some framework whose-name-i-didnt-catch. Maybe Dan will edit this part.
And Monday’s MMM workshop — Great Success — we had five or six fresh faces and it seemed that a good time was had by all. We were prepared with lecture materials, if needed, but everyone in attendance seemed to be in a loosely structured kind of mood — so loose, in fact, that we didn’t bother to take a single picture. PJ has suggested a Halloween theme for the next workshop, and we’ll probably prepare some reading and code snippets in advance on things like LEDs (charlie-plexing, POV and the like) and maybe some schematics and code involving upcycling old CD drives into creepy animatronics.
Yesterday we had the Philadelphia Robotics Group (PHROG) stop by for their monthly meeting. We demoed a few robots, talked other projects, and we also talked about the possibility of having classes and workshops in the future.
This robot requires 4 rotors to compensate for the amount of torque it generates.
The coolest part of the night was when Glen Adukas demoed his flying quadrotor robot. It still needs a few tweaks here and there, but he was able to get it off the ground.
Our next meeting will be October the 13th. Feel free to join us!
After speaking to a few folks that expressed an interest in the MMMM workshop, it became apparent (a) most folks were newbs who want to learn the basics and (b) everyone wants to control motors. Excellent! We’ll do that.
Although motor control is potentially a vast and complex topic, with highly specialized branches, the basics are fairly easy to learn — and they’ll take you pretty far. So … we’ll be prepared to present the following items:
DC motors
H-bridge circuits — these let puny microcontrollers run fairly powerful motors
Stepper motors — just a little more complex to program than DC motors and they use H-bridge circuits too
Quadrature Encoders — these are a simple and accurate way to read the position of something
We’ll also try to discuss some organizational items — like the logistics of future workshops and the use of the MMMM GitHub, so that we can build up assets collectively, share them with the world and manage changes and contributions in a free-and-easy-but-organized way.
If you are coming , please bring:
Yourself — If you’re a newb, welcome — If you’re an MCU Yoda, then attend you must and wisdom to newbs impart
Some ideas
A laptop if you have one
You may want to install VMWare Player or VMWare Fusion before you arrive
An MCU development kit if you have one or …
Some money if you don’t. We’ll have some development kits that you can buy. Plan on at least $10 for the kits and some parts that you can use for small learning projects.
A bread-board if you want to build some live circuits to keep. We’ll have breadboards to loan, but if you want to take one home, it has to be one that arrived with you.
That’s about it — see you all Monday. To whet your appetite, there is some prototype code below for reading a quadrature encoded position detector (not really elegant enough for a final effort, but it’s a start). We’ll have you writing stuff like this in no-time.
Rule #1: Don’t steal stuff.
Rule #2: Always be seeding.
Rule #3: Always have 3 rules. (I guess)
The more we use the internet, the bigger the files we move around get. There was a time when I carried around a 1.44MB floppy with all my important garbage on it. Then ZipDisks! 100MB of storage. omg. Well, now when I want to share a day’s worth of webcam footage, I need to find a way to get 4GB of video to 12 different people. This is where bittorrent shines.
Here’s a tiny vid to explain how it works. Basically, everyone downloads one piece of the file at a time until they have the whole enchilada. Then in theory, they continue to share their copies with other’s that don’t have it yet.
This makes it easy to download huge files from large groups of users. It’s true that most torrent traffic is used for sharing pirated work. But we won’t be telling you where to get any movies or anything. We want you to know how to share your own stuff with bittorrent!
