Motors used were:

Electronics:Stepper Motors used:NEMA 23′s

I have been playing around with creating enclosures for prototyping electronics as of late. Today I took a few hours while my son was napping to create a case for my Arduino Mega that I got recently. The typical wear and tear of breadboarding / protoyping with these cool uC’s can be pretty harsh, also knowing the common state of my workbench (screws, tools etc all in disarray) I find these cases completely necessary.

With the recent number of orders for the Bus Pirate V3 enclosure it seems obvious that I post up these other designs as products also. However, these still have quite a bit more testing and tweaking to go through before they are ready for the synthetos web store.

More pics here:

DISCLAIMER:  I know I go a bit crazy with the screws.  However my son says it looks like a robot with them so oh well!  If you build your own you will not need this many

This past weekend I decided that I would attempt a carbon filtering fume extractor stack (at least what I called it).  Basically the fumes from the smoke of many different materials is pretty bad.  The idea was to make it so the carbon would filter the smoke and output clean air (ok well a best hopes less smelly air).  Heres some photos of the build.  I will be putting the whole thing on thingiverse soon.  I do not like how the filters are working out.  They were the carbon filters you can cut to size from home depot.  I have a different idea how to make your own carbon filters from masonite, screen door material and the laser cutter.  I will post an update here soon.  Check back to this page to get updates on this project.  I have a lot more pictures on my flickr stream.

This little stepper motor with a PC fan blade is hooked up to 2 LEDs. When the fume extractor is turned on the air flows from the top of the "SYNstractor to the bottom" thus spinning the fan (stepper motor) generating a few volts to turn on the robot eyes!. Super cool IMO. Not sure if it will work but I think once the filters get too dirty then the LEDS will start to dim. But if not.. its super cool that this robot comes to life. Attrib: I got the robot logo from this website. blog.analogmedium.com/2008/05/am-scrape-may-part-i.html

Hide the all of the layers.  Then display only the Dimension and Tcream.  (Note: in the screen shot its the document.. it needs to be Dimension).  Also change the fill style for the cream layer.  It is a “hatch” looking pattern by default.  We want a solid color pattern.  I left the color Grey.  When we print the PDF it will turn it black anyways so it does not matter. Click ok.

Now you need to click Print and then click the PDF button.  This is going to get us a vector format of the stencil.  However, for some weird reason the PDF writer in EAGLE creates some sort of non-standard PDF (not sure exactly).  This does not allow us to just import this into Corel Draw (corel is what the vector cutting drivers work  for the epilog laser cutter).

So scroll down to see the next step.

Now you will need to download Ghostscript and Gview for your platform.  Here is the windows links.
http://mirror.cs.wisc.edu/pub/mirrors/ghost/GPL/gs864/gs864w32.exe – Ghostview
http://mirror.cs.wisc.edu/pub/mirrors/ghost/ghostgum/gsv49w32.exe – Gview (Windows GUI for Ghost Script)

Ok once those are installed go ahead and open Gview and then open the PDF we created above.

Now click File >> Convert.  Select the EPS Write and type in 1200 dpi.  Then click OK and save it. You now have the file you will be loading into the epilog laser cutter.

Open up Corel draw… Ungroup everything (if needed) and check the outside lines for duplicates.. Meaning select a outer line and delete it… If you see another line.. Delete that one until the lines are no more.. Then just undo the last delete.  Why do we do that?  For some reason Ghostscript from time to time adds multiple lines on the outside.. Not sure why.  But if we do not delete them we will have the laser cutter going over everything (at least the outter edges) 2x or 3x.  Ok so you have removed all duplicated lines and now you are ready to select all and make the line width a “hairline” width.  This is something that corel calls it.  This is the #1 reason that you can only use Corel draw to do cuts (vector stuff) with the epilog.  So anyhow.. Now you should print it out.  Setup your desired epilog settings (based on your material) and have at it.

Your done!   (DFX is here: Goodget 2.1 stencil dxf)

So I had some free time while waiting for Alden to proof my xproto breakout board I designed for the tinyG system that we are working on.  So I took some time to try to mimic the results that Joe Grand of Grand Idea Studios did on his professional PCB mill.  I think the results were pretty good.  In fact they were even better than you see on the final version.  I say this because currently I have a very coarse wire brush on my grinder and did not take the time to switch it to a much finer wire gauge.  I was lazy.  As you can see some of the building is coming off.

Also in the middle there was some “over burn” where I left it in contact too long.

This has kind of inspired me to do some neat graphic / electronics.  Not sure what I am going to do but this would have been much cooler if the cyborg’s eye lit up and would blink faster / slower based off of the temp in the room etc…

The oomlaut open source robot arm base assembled easily and looks slick and professional.

Thanks to Riley, I am the proud owner of a pile of lasercut parts for the uber-cool oomlaut open source robot arm. The details can be had from both the original blog post and a thingiverse.com post that has the necessary design files (nicely laid out for the lasercutter, although Riley was able to get the layout down to a single 12x24in sheet, which was great. He said he will upload it as a derivative on thingiverse ASAP, so others can benefit, too.) My daughter and I both thought watching it cut was the coolest thing ever. She has taken all the scrap and has it proudly displayed in her room, too. It helps that the color we chose was bright red- gives it a gem-like (and somewhat sinister!) appearance. Can’t beat that!

I have most of the electronics already- I will be using a barebones Arduino as the controller, and a Pololu servo interface board to maximize the precision. I did have to order some good metal-gear servos, which I got for a steal at dealextreme.com The total cost of the project will be about 70$US, and if I had to buy everything fresh, closer to 100$US. Pretty good for a flexible robot arm and experimental hacking platform. My intent is to incorporate it into some work that colleagues and I have been doing around automated lab testing. I intend to borrow an existing reverse kinetics framework and use that for path planning. I am also going to rework the gripper, as I think it is the weakest part of the design.

Next up will be an illustrated build diary, here on the Synthetos blog, and a compete set of instructions, ordering guide, etc., over at Instructables. The goal is to get the arm built and tested, and to validate the design, as well as get others interested in building their own. Who knows- if it works out well, I may even take a crack at a derivative design that can be built using only RepRap-ed parts!

I picked the ~250w amplifier for musical instruments (short circuit protection, etc) which is not the best performing of the bunch but is a good compromise between complexity and performance.

This is probably copyrighted, but it just to get the idea (fair use)

Armed with some copper clad and spray paint, I went over to the Synthetos Laboratory for some rapid prototyping of this 0.05% THD amplifier. Step one is to paint the copper clad with spray paint primer. Step two is to import the layout (scanned at 1200 dpi-native res for the lazor etcher), cleaned it up a bit in Photoshop then presented it as a print out to the Laser Etcher.

Laser Etcher about 50% through the Copper Clad

As you can see, the laser etcher prints on the copper clad by removing the spray paint primer, which exposes the copper. Next up, is the traditional Ferric Chloride solution which removes the copper from the clad material.

Removed Copper

After etching, the exposed copper dissolves in to the Ferric Chloride solution (oxidation/reduction?) and what is left is the covered copper (with spray paint primer) and the see through clad material. At this step, I tried to use Paint thinner to remove the spray paint.

Notice the Sponge Brush

The sponge brush that I got from the paint section at Home Depot is a great tool. Along with a plastic/rubber paint tray, I was able to use only a small amount of Ferric Chloride to remove the copper. Basically I poured a small amount in to the plastic tray, and brushed the copper clad continuously until the copper came off in about 15 mins. No heating was required, and compared to the amount of Ferric Chloride saved (vs using complete submersion), this was well the effort.

Unfortunately, the paint thinner didn’t quite work, or maybe I didn’t rub it hard enough. I then used some nail polish remover (Fisher Scientific acetone passed away) and some #0000 steel wool to remove the paint. Below is whats left.

Close Up of the Finished Board

A nice feature of the laser etcher is that it works on so many different materials for just as many uses. Below is the ‘top’ side print of the components.

Components Side Print on the Single Sided Copper Clad Board

The beauty of this is that all of this was done, in one evening!

And now, I’m off for some classical music!! Ciao.

I have blogged about laser etching PCB’s in the past (you can read about it here).  The inherit problem with laser etching PCB’s is that is it very hard to get aligned if its a double sided board.  So I modified Zach’s design to be a single sided board.  Its tight in some spots but if you use the solder mask I created and have a somewhat steady hand its doable.  Here are some pictures of the process and a video of it working!

The AS5306 can be found here:
http://www.austriamicrosystems.com/eng/Products/Magnetic-Encoders/Linear-Encoders/AS5306

Thingiverse entry and files here:
http://www.thingiverse.com/thing:1409

I am using a method that I invented I termed:  Self threading square tube insert method. Whats so cool about this is it combines fairly easy cuts of aluminum that pretty much anyone can do with a band saw, hand saw or rusty pocket knife… Well not the last one and I don’t suggest you try it.  But is very cool.  Basically its all in the spacing of the 4 holes that were laser cut that the aluminum sits below.  Its a very tight squeeze which allows the screws to “self thread” inside the square tube’s inside.  Hence the name.  Not super witty but it describes it nicely.   Comments, questions or concerns always welcome.  Next thing to make is the collet holder.

Here is the final results:
http://www.thingiverse.com/thing:1393

Thingiverse Links as always here:
http://www.thingiverse.com/thing:1393

However, My metal cutting table has clamping T’s that little bits of metal would fall down into and become very much of a pain to clean.  So I decided to fab a part in google sketchup for the T slots to help extract the junk.  So a few quick measurements with my digital caliper and I was good to go.

Thingiverse Part Here: http://www.thingiverse.com/thing:1372

Here is the final product: