Tag Archive | Philadelphia

NASA Space Apps Challenge

The Skirt Begins

The Skirt Begins

It has been a while since I posted.  There have been updates to Arduino, changes in the CapSense library and finally, some major issues with my old laptop.  I basically reached a standstill.  In the meantime, I heard about the NASA Space Apps Challenge and wanted to give it a try.  This two day event allows makers to come up with apps, programs or other tech objects to help NASA.  There was a specific challenge called “We Love Data” that got me excited, because it explored new ways to visualize data.  I found the information about the International Space Station pretty interesting — it’s basically orbiting earth a few times a day, and most people are unaware of it.  How could I visualize that?  Almost instantly I got the idea of a skirt that would show the orbit of the space station around the earth —  an Orbit Skirt!  I knew I could use Lilypad Arduino and LED’s to show the path.  Then the programming could allow the LED’s to blink in such a way that they would show how far along the space station was in its orbit.  Doing all of this in two days was going to be rough, so I posted on NASA’s website for a team member.  I got lucky, because a wonderful woman named J. Brooks Zurn with an engineering background answered the call.  While I spent time creating the skirt, she would work on the programming.

I started  by taking one of NASA’s photos of the earth and making it into an iron on graphic.  Then I used the handy Lilypad stickers to layout the locations of all the electronics so I could create chalk lines for the stitching.  Stitching 17 LED’s into a skirt without crossing conductive thread paths was challenging, and keeping the Arduino and battery pack hidden in the skirt’s pocket lining was even trickier.  By the time things were finished, I could barely get the programming cable into the skirt to meet the Arduino.  There’s certainly something to be said for accessibility.  In any case, the sewing was completed just as Brooks was emailing her latest version of the code.

Space App Judges

Surrounded by the Judges

We finished with 15 min. to spare — just in time to present.  My whole goal was to complete the hackathon, so I had no strategy in place for the presentation.  Meanwhile, other groups were swiftly putting together graphics and power point presentations.  Finally I was forced to wing it.  I told the story of the underdog (me) with barely a hackathon under my belt, and how I had managed to take on all of these new skills and a team member to complete this skirt.  It must have worked, because Brooks and I got third place and we both received huge boxes of K’Nex toys.  Here’s a video of the finished skirt — can’t wait to come up with the men’s tie version.


Testing CapSense

Although Arduino has many fun programs in its library, I was in search of something a little more touchy-feely.  To be more specific, something that is touch sensitive.  I found out that someone had written a CapSense program for Arduino here.  This program gives the user the ability to create an object that when touched, will trigger an event.  Think of those lamps that when you touch the base, they act as a switch adjusting the brightness of the lamp or turning it on/off.  Sounds useful, right?  So, I set about uploading the program and doing a test.

The Lilypad Arduino has what is called pins around the outside circle.  That is a very electronic term, but basically they are the little holes you see on the edges that allow you to attach parts.  I’m just going to call them petals because the whole thing looks like a flower anyway.  Leah has a great diagram here to show what these petals are called.  Notice that some of them are marked “D” and some of them are marked “A” — this means Digital vs. Analog.  More on that when it is appropriate.

The way this capacitive sensing works is that it measures the electrical capacitance of skin as it touches or nears a pin.  In fact, it is similar to what a lie detector test is doing when you are hooked up — except the detector is looking more at changes from emotional stimuli rather than touch vs. no touch.  For my project, all I need is the second.  It takes two pins for each touch sensitive area, so I first had to connect a 1 M resistor between two of the petals that are used in the program.  I didn’t want to solder or use conductive thread since this was just an experiment, so I utilized a breadboard (not to be mistaken for my cutting board).  A breadboard allows you to connect various parts of a circuit and just use alligator clips to connect to your project for testing.  Once I had the resistor in place, then I needed something to act as the conductive metal to “touch” in order to trigger change in the program.  Some people make simple piano keys using some copper tape, but I decided to use conductive yarn.

So, here you have the setup, the alligator clips lead to the breadboard with the resistor and then there is the conductive yarn ready to be touched.  Remember the power is actually coming from the USB connector attached to my PC.  There’s one other thing that I want to point out here, I’m also using a circular yellow piece of craft foam as a coaster underneath the Lilypad.  This coaster allows you to clip things on without the whole thing sliding around — quite handy.  So, now it’s time to do the test.  First I have to turn on the Arduino monitor to allow me to see live data flowing, which  in this case will be numeric values for the petals in operation.  This particular CapSense sample program uses three possible touch sensitive areas, but I’ve only hooked up one for the test.  So, that means there will be three columns of values with only one column actually activated.  Let’s see what happens when I touch the yarn…

As you can see in the first column, there is a string of relatively low numbers which then shoot up at line 3907.  That is where I touched the yarn — success!  Notice they drop down again a few lines later once I’ve released the yarn.  This is exactly what I was hoping for.  So, in my case, I want the project to sense when I’ve touched yarn, in order to trigger a sound.  However, I won’t be able to get to that until I’ve done another round of testing with CapSense with more inputs.  I would really like to figure out how to have six to eight touchable areas instead of just three.  That will probably take some minor code hacking, but I’m not worried as it’s already been a great day.  Now I have to plan a visit to Radio Shack in order to get more 1M resistors.  I used to work at Radio Shack a very long time ago, and it’s still funny that I remember codes for some of the part items.  So geeky.  Sayonara!

Hello world!

There are more females than you know working with technology and their uses may surprise you.  Tech is part of our art, clothing and even food.  Let my adventures in circuits and interactive design be an inspiration for you to follow your own passion.  Like you, I discovered most of the things I’m exploring from the web.  What started with meeting a few guys at a hacker space has now ended up with me exploring soft circuits, teaching a felt LED flower class, attending an AdaCamp DC, and now doing art of my own.  Where will you end up?  That’s all part of the mystery.  Be a geisha and dance your own work.