Tuesday, January 26, 2016

LogoTurtle Fractal Designs

I was inspired by Erik Nauman's Generative Art and the LogoTurtle post and decided to program some fractal art for the LogoTurtle to draw.

First, I reached out to Erik for a little assistance adapting my TurtleArt Dragon Curve procedure to LogoTurtle. He and Brian helped me by building a little random number generator that helps determine whether the LogoTurtle turns right or left 90 degrees.

to dragon.curve
repeat 100 [
fd 50
ifelse (random 0 10) < 5
[rt 90]
[lt 90]
This procedure calls for repeating many times or even looping infinitely. The only limitation is the amount of ink in the pen and the size of your canvas!

The next procedure was adapted from Michael Friendly's Advanced Logo. I have been wanting to understand and create a tree pattern like this for some time: this exercise put me on that path.

to tree2 :len :depth :ang
if :depth = 0 [stop]
lt :ang fd :len
tree2 :len (:depth - 1) :ang
bk :len rt 2 * :ang
fd :len
tree2 :len (:depth - 1) :ang
bk :len lt :ang
 First, I ran it small with the following procedure:
rt 60 
rt 60 
back 100 
repeat 3 [tree2 20 5 12 lt 60] 

The design is surprisingly organic and beautiful. The trunk is not quite right, though.

The next time I ran it I sized it up considerably:
to startup
wait 1000
rt 60
repeat 3 [
tree2 100 5 12 lt 60]
rt 120
bk 100

It was also beautiful.

LogoTurtle, like elsewhere, proves to be a fun and beautiful place to examine fractals and mathematics.

Sunday, January 17, 2016

Mint Tin Drawdio

For the discerning Drawdio player on the go, I offer the Mint Tin Drawdio. Built on an Adafruit Mint Tin protoboard, this Drawdio is just as loud as my previous cigar box housed version but packs portability, loudness, and urban styling into a sleek package.

This was my first project using a protoboard, and I have to say I loved it. My soldering skills are improving with each project. Some of the connections probably warranted a finer-tipped soldering iron than I was using, but everything worked out. I have learned the skill of heating the elements I wish to solder and being skimpy with the amount of solder I use: a little goes a long way.

I remixed a design from Thingiverse to create a 3D printed bumper to insulate the components on the protoboard from the tin.

With all the parts in place, I drilled holes for 8mm M3 hex head bolts to hold the bumper and protoboard in the tin. I also drilled holes for the power wires and the contact wires. I used a pair of snips to cut a slit in the front of the tin and bent it back to allow the speaker wires a route out of the tin.

@zackboston gave me the awesome Altoid tin, decorated by students at the South End Technology Center.

This Drawdio can easily be slipped into a pocket or even incorporated into my sport coat!

I wanted to protect the speaker from being damaged while it was out in the world. I used one of the Turtle Block designs from my Sunflower project to make a grille, then built a housing as well. The grille and lid press-fit together perfectly.

Finally, I designed a bracket that holds the battery and the speaker. The bracket attaches to the rear of the mint tin by means of three press-fit rare earth magnets. Both the battery and speaker can be removed from the bracket for jamming out.

Friday, January 15, 2016


Brian Silverman, Erik Nauman, and I worked to bring Brian's LogoTurtle to an Adafruit Metro Mini-based robot. Warm up the 3D printer and soldering iron and build your own for about US $60 in parts.

Monday, January 11, 2016

Homebrew Drawdio

Jay Silver helped me build a Drawdio to his original specifications! We used his original schematic from his web site, which is for a PCB, not a breadboard. It took some figuring out but Jay treated the project as an opportunity to teach me so much about circuitry, how a breadboard works, and how components in circuitry work. In the end we hooked up the battery and tried it out.

Success! Since the circuit uses a 9v battery instead of a single AAA and has a large 8 ohm speaker in place of the Drawdio's .5 ohm, it is loud!

This Drawdio circuit is so loud I put it in a box!

I cut a hole in the bottom of the cigar box with a jig saw (not my best cut, but at least it is on the bottom). I used a Turtle Blocks design I previously programmed as a speaker grill and holder and 3D printed it. 

Likewise, I 3D printed a battery holder

The two wires to which you connect the world to the Drawdio were secured to the top of the box with a pair of 8mm M3 bolts, washers, and nuts.

I soldered a wire to the metal tip of a fantastic mechanical pencil that Jay gave me. The wire winds around the pencil and has a loop at the top for an alligator clip.

My friend came over and jammed out with the Drawdio, a wet plastic placemat, and my son!

I finished off the project with a 3D printed pencil holder. I holds then pencil inside the box when not in use.

Theremin Sport Coat

Jay Silver worked on a great project called ok2touch that used conductive thread and circuitry to explore "empathetic contact" and creating sounds through touching skin to skin. I remixed this project using two of Jay's other projects, Drawdio and Colorforms' Brush with Genius, to create a Theremin Sport Coat.

I started with an Adafruit assembled Drawdio fun pack and a laser cut Drawdio holder. I used a really heavy weight conductive thread and put some truly Frankensteinian stitches in the arm of a sport coat. I sewed some "pads" as well to make piano-type keys on one sleeve. One of the pads connected to the other end of the Drawdio so a complete circuit could be formed if somebody touched and connected the two pads.

I placed the Drawdio and holder on the lapel and sewed a circuit in the lining. 

Once it was working I took it out into the world with my son to play around with conductivity.

The design left little to be desired. I also talked with Jay about the Drawdio and Brush with Genius, and it turns out the Brush With Genius used the 555 timer, like Jay's original Drawdio built from a PicoCricket, instead of the Adafruit 551. I purchased a second Brush With Genius to take it apart and repackage the circuitry.

I used TurtleArt to program all the designs to be 3D printed. The designs were extruded and sized in Tinkercad then downloaded for 3D printing on my Thing-O-Matic.

I started with the speaker grill and speaker holder.

The stem was mounted to a laser cut wooden Drawdio holder with screws and M3 bolts.

A "vase" held the circuitry.

Longer leads to connect the circuit to the sport coat soft circuitry were soldered to the board. Additionally, connectors for the power supply, a holder with 2AAA batteries, were soldered to the board.

Attached to the lapel and powered on, the boutonniere is ready to squawk! There are pads on the end of each sleeve that I can hold on to if I need to bust out a solo, or I can old one opposite of the sleeve somebody else touches while we hold hands!

Although this is an simple wearable project, it brings smiles to everyone who interacts with it!