Thing a Day 27: A Little Pushback

Usually I have a clear idea of what I could do with a Thing that I build. Not so much with this one.

It's still cool, though.

What I accomplished, though, is attaching a flex sensor to a motor. When you flex the sensor, the motor reacts by jamming itself toward your hand -- usually bending the sensor some more, which makes the motor shove forward even more.

Fortunately for my hand, the entire setup is pretty shaky. Cardboard arm attached to a nylon motor arm with a piece of crimped wire, gently held in a vice so I don't crush the entire thing.. Also, the motor stops pushing if you stop flexing the sensor. Maybe that means that the sensor should be called a flexing sensor.

Anyway, I like it. If you poke the sensor just right, it flips out. If you poke it gently or too roughly, it'll twitch a little. Just like -- wait, what?

Thing a Day 26: Violence and Robotics

For today's thing, I decided to get a motor to whack paper out of the way of a light sensor.

First off, I should give credit to the source. Over on the YouTubes, roboanalogtom put together a wonderful video on analog electronics, which includes a ton of rapid fire schematics and projects that can be done. I ended up sticking with the first one, which is simply making a servo motor responsive to light.

In the first part of the video, you can see me waving my hand and finger over a small light sensor on the breadboard. Each time I do that, shadow falls on the sensor, and the fancy pants cardboard arm of the servo moves.

When I move the cardboard arm over the light sensor, I get a nifty feedback loop: shadow falls over the sensor, which triggers the movement of the arm, which removes the shadow, so the arm moves back, so shadow falls over the sensor, which... If I put an intermediary between the cardboard arm and the light, I get a niftier effect: the cardboard arm will whack things out of the way when they cast a shadow over the sensor.

Violence and robotics -- what could ever go wrong?

Thing a Day 25: Homemade Lockpick Part 2

And so it continues.

As soon as I got home, I busted out the tungsten carbide bit and Dremel and started shaping the pick. I figured that if I could the loud noises out of the way earlier on in the day, I'd be less of an inconvenience to my neighbor.

Of course, I've never even seen the person in the apartment above me, so I have no idea if they're raging about my noisiness or completely ignorant of it. What I do know is that the pick is coming along nicely. I managed to get the inner curve of the pick well shaped with the carbide bit in a short amount of time, which gave me a comfortable amount of time to try polishing the sharp and rough edges. A bit of high speed sanding and some polishing with 600-grit sandpaper gave it quite the smooth finish.

One problem: Metal. Bits. Everywhere. None of the material I removed came off in a clean chunk; it sprayed off as tiny bits of sharp metal. I had to scrub my arms as soon as I was done, else the metal dust between my fingers would've driven me crazy.

Thing a Day 24: Homemade Lockpicks

We've got a rude one!

After yesterday's fun picking that horridly cheap lock, I decided that I wanted to try something I never had the chance to: make my own pick. I'm not really at the point where I need more picks, but it's an interesting challenge -- and one that create pretty sparks.

After a trip to Lowe's, the first step was to heat treat the hacksaw blade so it'd be more workable. In order to do this, I needed to heat the blade quite a bit, and then let it cool slowly to room temperature. In letting the blade cool slowly (the slower the better,) you end up with a larger crystal grain in the metal -- which means the metal is softer and more workable. All of that meant that I was crouching on my porch with a propane torch, repeatedly heating the blade until it glowed red. This had the side effect of burning the paint off, which was convenient, given that I'm not sure how it would've interacted with the Dremel.

Speaking of Dremel, I next had to cut the 12" blade into two 6" blades. Unfortunately, as soon as I spun the tungsten carbide cutting bit up to 20,000 RPM, I realized that this wasn't going to be quiet.. And my worries were confirmed.

Cutting metal in my spare bedroom probably isn't too nice to the neighbors, which is why I only progressed to gently shaping the pick end. When I next work on this project, I'm going to have to pick a very polite time of day and restrict the amount of shaping I do. Sooner or later, though, I'm going to have a new lockpick.

Thing a Day 23: Quick (Very Quick) and Dirty Lockpicking

For today's trick, I will pick a cheap lock three times in 45 seconds. No, really.

It's been almost half a year since I've held a lockpick in my hands, so it feels good to use them again. Unfortunately, I was a beginner half a year ago, so I'm nearly retarded today. Fortunately, half a year ago, I bought a horrendously cheap lock that will at least boost my confidence.

As evidenced by the fact that I picked it three times in 45 seconds.

It's worth mentioning, however, that the technique I'm using to pick this lock is called raking. Raking is somewhat like the brute forcing of lock picking. You might accomplish something, but you won't learn as much, and it definitely won't be that easy on a better lock. It is a skill that's useful, though -- and I've noticed that my raking skills improved on the cheapy lock as I practiced.

Thing a Day 22: A Wikipedia Article

Articles for Creation: Limor Fried

Given that I play with electronics a lot, I follow a few sources online for information. One of them, adafruit.com, has been a great resource for tutorials, kits, and a handy Saturday night Ask an Engineer show.

When I found out today that she received the award of being one of Fast Company's 2011 Most Influential Women in Tech, I popped over to her Wikipedia article, and found.. Nothing. There were a couple of references on other Wikipedia pages, but no real bio.

So I created one. I've done minor editing on Wikipedia before, but I've never been bold. After some research, I was able to whip together a framework with some references and a brief outline. Hopefully it's a good template that it can be expanded and turned into an article. And if not, hopefully I'll get enough feedback from Wikipedia that I'll know more next time I need to create a Wikipedia article.

Thing a Day 21: Scheming Roadblock

Today's thing.. Was an exercise in frustration.

While soldering the above (secret) Thing, I made the fatal mistake of designing as I go. For something temporary like prototyping on a solderless breadboard, that's not much of an issue. But when you've got a 700 degree soldering iron and you're making semi-permanent decisions, it can be a bit frustrating.

So, after a mistake or two and some necessary rewiring (hurray for visual inspection,) I connect the battery.. And it doesn't work. The sound it makes is weak, the sensor isn't working, I'm getting frustrated. Which means tomorrow, I get to debug it.

Maybe it's time to paint some more miniatures.

Thing a Day 20: Scheming Schematic Planning

Admittedly, this Thing isn't so much a thing as it is an accomplishment.

For this project, I'd like to actually make it permanent -- which means not only designing and testing a prototype, but figuring out how to lay it out on the PCB before I bust out the soldering iron. In other words, I have to translate the penciled schematic into that tan PCB.

I was a little worried at first, but then I to try a few things out. I should have plenty of room for that I intend to do.

Of course, I can't outright tell you what I'm making. It's a seeeecret.

Thing a Day 19: Basecoating Fun

Despite focusing on electronics for the past 18 Things, there _is_ something else I do in my workroom. It involves plastic miniatures, superglue, paint, and a completely separate workspace. For today's Thing, I took it upon myself to do something I've been slacking on: I basecoated some minis.

When painting miniatures with acrylic paint, the paint tends to bead up due to surface tension, and will be prone to chipping over time. The best way to prevent this is by basecoating the mini with a neutral color, usually via spraypaint. Spraypaint adheres to the mini far better, is much faster than a brush, and prevents the later acrylic paint from beading.

So, today, I taped together a cardboard box to protect my porch and started spraying some models that have been waiting for the chance. Maybe next I'll dust off my brushes and actually get to slinging paint. ;)

Thing a Day 18: The Switch that Won't Turn Off

It's so nice when things work.

Yesterday's failed project turned into today's success, now that I know what I'm doing. Funny..

The description of today's Thing is in the video, so I won't repeat myself. Instead, a purpose: In a future super secret Thing, I'll be able to use this as sort of a one way light sensing switch. Once lights shines on it, you'll have to break the circuit some other way to turn it off. Darkness simply won't do!

Thing a Day 17: Failed Latch-on Transistor

I thought I had it. I thought I knew what I was doing -- I thought I could create a switch that, once it received a bit of current, would keep itself on. I was wrong. I failed; it doesn't work.

But that's okay. ;) This was supposed to be a quick "Slap these parts together and you'll have a light switch that won't turn off when it's dark again. Then you can get to the next step of the project!", but there's a gap in my knowledge about transistors somewhere. I think I'm getting a runaway effect where the transistor slowly turns itself off after the light sensor goes dark. But without an oscilloscope..

Time to hit the books! If I can't find a solution, I'll have to hack togeth..er.. Actually, all I'll need to do is slap an NPN transistor into that circuit and I'll have a thyristor. Duh.

Tomorrow's Thing a Day: Homemade thyristor!

Thing a Day 16: Arduino and LED Ticker

Scrolling LEDs. That's all, really.

No, of course it isn't. I wouldn't leave you with just that. What's going on here is that I have an Arduino generating a random number (0 or 1,) and then it's feeding that number to the shift register on the breadboard. Throw in some signalling so the shift register knows when to look for that number, and the shift register then proceeds to light up an LED for a 1 and turn off an LED for a 0. Do it again and the light pattern shifts to the left to make room. Hence, shift register!

The ultimate question: Why? Well, if you notice, I've got the sequence ticking from right to left -- just like it would if I had lots of LEDs wired up to display a message.

Thing a Day 15: The F*!(ing Sequencer is Back

This time it's pretty, more functional, easier to use, better pitched, and has an NES controller!

There's a lot going on, so I had to explain it in the video -- but the gist is you select which notes you wish to make sound with the left/right and A buttons on the NES controller, adjust the actual note to play with the up/down buttons, and hit start to loop the sequence. 16 notes, about 250 milliseconds per note, C major.

As a side note, the interface is a bit sloppy. You can see me having some very minor timing issues with the A button in the video -- that's because the code is simply checking to see if the button is held down, not whether it's a new button press or anything fancy. But.. Whatever. It makes something resembling music. ;)

Thing a Day 14: NES Pixel Test

Today, I went old school. Sort of. Well, knock-off old school, given that the NES-style controller that I'm using isn't authentic.

What's going on? I'm using an Arduino (microcontroller) to drive a backlit LCD screen, and I'm using the NES controller (plus connector adapter) to move around the shorter of the 16 black boxes. Nothing terribly fancy -- but it's a step in the right direction for the super secret project that I'm building.

Of course, you might very well be able to guess what I'm working toward.. ;)

Thing a Day 13: Will the 555 Sequencer Ever End?

Will I ever stop demoing this 555 sequencer? Probably, but maybe not.

However, this would be as good a stopping point as any. This time, I added three potentiometers in place of the normal resistors -- which lets me vary the pitch of each of the three notes far more easily than before.

In case you're wondering why I keep hammering away at this project, it's because I'm getting it to be somewhat presentable for the 555 Contest -- a contest based on the 555 timer, started/organized by Jeri Ellsworth. Unlikely that I'll win any awards for my project, but at least I can get a sense of accomplishment out of it. =)

Thing a Day 12: 555 Music Sequencer Part 3

This time, that singular note was joined by two friends. Things are getting a little cramped on the board, though, so I doubt I'll add more notes -- my proof of concept is solid. =)

However.. I would like to add more control of the notes, as well as on/off switches for each one, sort of like a normal sequencer. Next time!

As a little bonus at the end of the video, I demonstrated some circuit bending. Lots of hackers have started to pull apart cheap electronic toys (like Speak and Spells) and modifying the innards, making them create sounds that the designers never intended to. At the end of this video, I'm touching some pitch-control resistors with my bare hand, which alters their value -- thereby changing the pitch that the speaker produces. Fun!

Thing a Day 11: 555 Music Sequencer Part 2

A couple of Things ago, I made a noise maker. Thing before that, I made a ring oscillator.

Today, I have combined their powers!

What you see above is the first note in a sequencer. It isn't very interesting by itself, but in the next Thing, this single note will probably be combined with its brethren -- two more notes, probably of a different pitch.

This one took a while, for two reasons.

First, I'm designing the first note so that I can simply copy (and paste?) the changes for the second and third note. In other words, the connection between the sequencer stuff on the left and the noisy stuff on the right is modular, as it were, so doing it two more times will be really easy.

Second, I'm not really sure of what I'm doing. I have some basic understanding of what's going on, but engineering is different than science -- and without a good grasp of the science, the engineering involves a lot of guesswork.

Thing a Day 10: Debian on Android

I've been meaning to do this for a while, but a friend borrowing my HTC Dream made me dig it out of storage and bring it to my attention. What you see above is Debian being installed on the first Android phone.

I've been working at it for a few hours, but it's mostly just been waiting around while I root my phone or install Cyanogenmod or package up the ported version of Debian, et cetera. Regardless, what I'll end up with is a phone that runs Linux (even moreso than Android does.)

Once I get the Apache webserver running on my phone, I'm going to be giddy for a few days.

P.S.: If you'd like to give it a shot, zed0 has some updated instructions on how to get it going for the most recent Cyanogenmod.

Thing a Day 9: 555 Sequencer Part 1

In classic me fashion, I've dropped the Atari Punk Console from Thing a Day 2 and rolled the design back to a simple noise maker.. For now. In the long run, the result will be much more epic.

Combining the above 555 noise maker with yesterday's Thing, a ring oscillator, I'll get a basic sequencer -- which is the workhorse of electronica. With a sequencer, I can set up a pattern of notes to play and loop that pattern. Of course, by notes, I mean squeals, and by pattern I mean odd number of beats that will likely be limited to three. ;) Tomorrow, I'd like to see if I can get the two connected for an actual sequenced result.

555 timers everywhere!

Thing a Day 8: 555 Ring Oscillator

The reason why I'm extremely proud of today's Thing? I came up with the idea, I sketched it out, I tested it in a half-arsed simulator, and then I implemented it and debugged it. And then, most importantly, it worked!

Well, maybe more importantly would be: what is it? It's a ring oscillator made from 555 timers. 555 timers are the same thing I used in the Thing a Day 2's Atari Punk Console. In that case, I had the 555 timers oscillating on their own -- which is important if you want to generate a sound. In this case, however, I have the 555 timers chained together in monostable mode -- which is to say, each of those black chips is telling the chip to its right when to turn off the light. With that red cord at the bottom, the chip to the further right tells the chip to the furthest left when to turn off. Hence, the ring.

I wasn't sure if it was going to work, especially when I had the light to the far right hooked up. In fact, I had uploaded a YouTube video and was about to write about tomorrow's Thing being a debugging session of what looked like a broken ring oscillator. Then, bam! Epiphany, debug, revideo, new post.

So, there you have it. The first thing that was born solely from my own mind* (that actually worked.)

* For what it's worth, the reason I can't find anything on Google about 555 ring oscillators is because it's horribly inefficient design. ;)

Thing a Day 7: Low Tech Reuse

Thought you'd see just me soldering and blinking lights, didn't you? Today, I went low-tech: making cardboard storage bins!

I saw some $0.47 bins over at Make: Online, and I realized that, first, those would be useful -- and second, I had all the materials I needed to make them. Those materials consist of scissors, some cardboard U-Haul boxes that I should've recycled two months ago, and some white glue. After drawing up a template on paper, I simply cut out the boxes and glued the back.

Since the bins are far sturdier than I expected, I'm keeping them! I might even make more, since I can make four per medium sized U-Haul box.

(Rough bin dimensions: 4"x6"x4".)

Thing a Day 6: Shave and a Haircut

Thing a Day 5's fairly tedious work has come to a glorious conclusion! Today, I uploaded my first program to the MSP430 microcontroller. The video above demonstrates my masterpiece.

So.. Clearly just a proof of concept. I learned that Arduino users have it really nice; the MSP430 on Linux is quite rough around the edges. Also, I'm going to have to dive into some tutorials to figure out how to manipulate the real world via this microcontroller.

I'm glad I got it working, though. It's good to broaden my horizons beyond the hand holding (excellently done that it is!) that the Arduino provides.

P.S.: Your computer has somewhere around 16,777,216 times as much RAM as the MSP430 (128 bytes!) in the video above.

Thing a Day 5: Texas Instruments MSP430 Launchpad

Today's thing is a bit difficult to provide media for, so I simply took a picture of what I'm working with.

I've tinkered with the Arduino for months now, including the projects for the first and fourth Thing a Day. The Arduino is an excellent microcontroller -- essentially an entire (but extremely simple) computer on a single chip -- including features such as open source, easy to use, robust, and well supported by the community. However, there are many, many other platforms out there, and one of them is the Texas Instruments MSP430.

The MSP430 is extremely cheap -- $4.50 for a dev board to the Arduino's $30 -- and low power, but it's also less powerful as a platform. In order to broaden my horizons, I grabbed three, assembled the one in the picture with some really quick soldering, and am currently waiting for the software to set up so I can start hacking on it tomorrow.

So: today's Thing is setting up everything to let me program the MSP430 chips. You'll simply have to make do with what almost looks like an advertisement for a picture. ;)

Thing a Day 4: Wireless Communication

Despite taking a few hours, this Thing is extremely simple to describe: I press a button on the right and a light on the left lights up.

Normally this project would be the first thing anyone breaking into electronics would do -- press button, turn on light. However, the light was simply an indicator to me that I was doing something else: making electronics communicate wirelessly. While there's a power plug running to the microcontroller on the right, the microcontroller on the left is completely self contained and is receiving information from the right by that blue wireless chip (known as an XBee) at the top of the screen.

This demo is a bit of a gateway drug. Now that I've worked out the kinks, I can start doing interesting things like wireless temperature sensors in my apartment. =D

Thing a Day 3: Solder Fume Extractor

Third thing, first failure!

This time, I set out to make a quick solder fume extractor. For anyone who's soldered, you'll know that the smoke that comes out is quite bad for you. The flux (rosin) that creates the smoke is exists to clean the metal surfaces of the parts you're soldering -- so despite its pleasant smell, it isn't a good thing to be breathing.

People who solder should always have a fume extractor, something I lacked. So, in classic "I can handle this!" fashion, I decided to take an old subwoofer enclosure, a 12V PC fan, and an A/C filter. After hacking it together with two screws and duct tape, I have what barely passes as a solder fume extractor. It's leaky, ugly, and the airflow is really bad.

A new one purchased from Amazon is $20, which is about what it'd cost to make this one work correctly and make it look decent. I might use it until I buy one from Amazon, but this hunk will end up disassembled or in the trash heap.

Thing a Day 2: Atari Punk Console

This jumbled hunk of poo is what's known as an Atari Punk Console (schematic acquired from Rob the Fiddler.) By twiddling those metal knobs dangling out there, you can change the sound coming out of the brass speaker -- a loud, shrill, 8-bit like sound. The cool thing about this setup, though, is that that the entire thing is analog. There are no microprocessors, and gates et cetera involved -- just old school technology.

Future plans with the Atari Punk Console include tweaking the potentiometers (metal knobs) for better sensitivity, cleaning up the layout, and soldering it to a real board so it can be for keeps.

Thing a Day 1: Boarduino

Considering this is day one of Thing a Day, I figured I'd start off with something somewhat interesting: a Boarduino. A Boarduino is based on the Arduino, but designed for easier breadboarding (hence Boarduino,) and it's cheaper due to the purchaser needing to assemble it by hand. Also, some functionality needs to be taken care of off board -- but that's fine, as it makes it smaller. All that, and I get to solder it myself!