Monday, October 6, 2014

My first Uncia print!

Finally stopped thinking about Uncia upgrades long enough to actually print something on the bot! Printed in MakerJuice SubG.

The color change of the resin is pretty interesting... but past that it's not the best model in the world. Granted, it's way better than nothing, but some calibration obviously needs to be done. What's pretty cool is that the only variables are resin exposure time, layer height, and the dwell period on each layer (to let the resin settle). Hopefully I can dial this in nice and quick!

Kudos to Uncia for making such a solid machine... and bigger kudos to Sedgewick for the original design!

The model I was trying to print was the 3D Hubs Marvin - Key Chain. Attribution!

Thursday, October 2, 2014

Uncia Electronics -- In Depth

I haven't seen this in a lot of other places, so it's going here!

The Uncia's electronics are (like the rest of the machine) and clone of Sedgewick's electronics. They comprise of a Teensy 2.0 and a single Pololu A4988 stepper driver. Also included is the smallest, most adorable 12V 1A power supply.

The two boards are mounted on a very simple circuit board.

Yes, that's all there is to it. Click the images to see a close up

It's a bit difficult to see all the connections. I've recreated the board in Fritzing.
This is a simple version -- It just shows what Teensy pins go where. Note that the LED shown is the signal LED that is on the Teensy itself.
Now for the real deal:

This is (I believe, unless I screwed up) the full breadboard for the Uncia.
Please note that Pin 10 is tied to a +5v. I'm not sure why this is the case (Since Pin 10 isn't even used in the firmware), and it doesn't make sense from a circuit design standpoint. I'm assuming it's a mistake. If you're ever pressed for pins enough to need number 10, it's easy enough to slash the thin trace that connects the pads.

Anyways, it's clear that the Teensy isn't being used to its full potential. This is actually pretty nice, as it allows for upgrades to the printer without having to swap the electronics!

With these upgrades in mind, I scribbled out the layout of the breakout pads that litter the board.

The layout of the three pads that line the board.
I don't like how the 5V pin is in between the GND and Signal pins -- it means that you can't just use a simple 2 pin BLS connector. C'est la vie, I suppose.

When programming new firmware in the Arduino IDE for Teensy (Teensyduino), just keep the following image in mind:
The numbers closer to the board are the pins called by Arduino code.
Note that pins 7 and 8 are both reserved for Rx and Tx -- if you attach inputs to these that force a HIGH or a LOW, you won't be able to upload new firmware.

All of this information will be used in the improvement of the Uncia firmware (Or should I say the Sedgewick firmware...). Check it out!

Wednesday, October 1, 2014

I finally understand GitHub!

So a few weeks ago my new Uncia DLP 3D Printer came in the mail. This is really some cutting edge technology, and I'm excited to be able to play around with it!

The hardware of the bot is pretty simple and solid -- a steel frame, a linear rail, and a stepper motor.

The electronics are a bit eccentric, however -- a stepper driver controlled by a Teensy 2.0!

The firmware's totally wonky -- it uses "pseudo gcode", and essentially expects the computer running the Teensy to do all calculations.

The software is nearly there -- I'm using Steve Hernandez's Creation Workshop, and, with the inclusion of a custom Uncia driver to support the weird firmware, it works pretty well.

There were some things that I wanted to change in the software, though... The first and foremost being the ability to turn off the damn motor! The electronics aren't tuned perfectly for the motor, so it hums pretty loudly, even while idle. There was a button on the CWS to turn off the motors, but it didn't do a thing.

So I turned to GitHub, and logged into my old account. How coincidental that I made my account on October 1st, 2012, and pushed my first commit Octobor 1st, 2014! Git's become a lot more usable since 2012 (At least on Windows).

You can see my repository here, but it probably won't be that interesting unless you also have an Uncia.

Hopefully that repo will see some serious action as I start to tune in my bot!

Tuesday, September 9, 2014

Circuit Board Get!

Today I received a nice, purple package in the mail!

My custom EarBeat 1.0 circuit boards! Still a little rough around the edges, but those are just the leftover breakout tabs from the routing process, and will sand down nicely.

It's hard to get a good sense of scale when the board is just a file on the screen. Having the boards in hand have made me realize just how small 8/16 SOIC really is! I've got one extra board to practice, though, and I'm confident that it will prove easier than it seems to solder the chips on.

Speaking of chips, this also came in the mail:

Lots of little electronics! The main pieces of this circuit are SOIC and 1206 SMD, so I really do mean little! For example: Here's my 16 pin decade counter.

Tomorrow I'm swinging by the store to grab my batteries for this, and then I'm off to the soldering station. Fingers crossed that this works!

(As an aside, my estimate in the previous post of $3 per ear was a little low. All components for the board comes out to $4.70, which is still less than the cost of a Arduino Nano! Not to shabby!)

Sunday, August 31, 2014

Circuit Board Design

So Halloween is one of my favorite holidays -- I love building costumes, and October 31st is great motivation to make and wear something cool.

Last year I attempted to make Guy's helmet, from Daft Punk:

Pretty sweet setup!

Long story short... It didn't work out so great. The funky visor shape necessitated a vacuum former, and my attempt to build one was less than satisfactory. In the end, I had to scrap the project, and just went as Finn, from Adventure Time.

This year will be different. I'm identifying my limits and working around them. I've purchased a raw pull of a helmet that came with a nice vac-formed visor, and have the side LEDs all set up (purchased from AlexPlusLEDs). Alex's LED set didn't include the "heartbeat" ear, however. Since it's a rather small and relatively simple circuit, I thought I'd try my hand at designing and building it!

The goal is to make the ear look like the following:

This would be an easy blink for an Arduino, but that's just too easy! Not to mention that even the smallest Arduino Nano's are around 5$ each.

I instead plan to use a 555 timer and a 4017 Decade Counter, which can be had for $0.55 and $0.45, respectively. Add in the random resistors, caps, and LEDs, and my total project cost is around 3$ for each ear. Not too shabby!

My board is designed in Fritzing, a great open source program that's incredibly easy to use. You start off by building your circuit on a digital breadboard:

Then you go over to the PCB tab, and arrange your board!

Once that's finished, I exported the Gerber files and sent it off to OSHPark to have the boards printed!

The result will be a very nice little board! Here's hoping that it actually works!

Saturday, May 17, 2014

Modifying a Logitech C310 webcam: Part II

In this post, I'm going to go over exactly how to prepare the C310 for use with the Oculus Rift.

This will be mostly picture driven, so if anything's unclear, leave a comment, and I'll try to fix it.

Start with a webcam, a small flathead screwdriver, and a small phillips head screwdriver.

Using the flathead, pry off the front faceplate

That's the microphone... try not to poke it too hard!

There are 3 screws on the front... remove them all

After the screws are removed, continue prying

Gently lift the front plate to reveal the circuitboard

There's the lens that we're interested in!
Removing the screws that hold the circuit board down...

...Make sure you get both!

Gently lift the board out. Be mindful of the wires and their connections.
The back of the board.

Pulling out this plug gives us a bit more slack to work with.

The lens and lens mount

The lens simply unscrews from the mount

That shiny bit is our sensor... don't let it get dusty!

This bit of glue on the lens keeps the camera in focus.

The C310's lens is not a standard size...
Since our new lens doesn't fit, we've got to replace the lens mount! Unscrew the two screws on the back.

The mount is glued down with a tacky glue. It's nervewracking pulling it off, but it's fine. Again, try not to let dust get on the sensor!

The fully exposed sensor.
Yeah, that's not happening.

So I designed and 3D printed my own mount

You can see the difference!

A perfect fit!
And reattached! I hope you saved the screws...

 Do this for both cams, and you're good to go!