This project went through many adaptations and in the end, it did not turn out as a blue box, but more like a weathered garden statue. The hydrostone did not turn out completely white, but grime on the urethane molds made little swirls, further enhancing the marbleized look. It is not bigger on the inside, but the wiring and battery did fit nicely within the internal cavity. A switch turns it on and off. Although this endeavour did not turn out exactly as planned, I learned many things about thinking in 3D and many more about construction and molding objects in 3D.

So what makes this model a “TARDIS” not just a model of a British police box that looks like a light-up garden statue? Honestly, nothing but my intent. I set out to make a model of the TARDIS and that is what it will be called.

The process I used to create this model:

Previous Posts:

1. I designed the TARDIS in Google Sketchup. > See Previous Post: TARDIS: 3D Modeling

2. I used the Modela to mill out the front, individual sides and roof of the model in machinable wax. > See Previous Post: TARDIS: Moldmaking

3. I used the block of machinable wax to create urethane molds of each of the pieces. > See Previous Post: TARDIS: Moldmaking

Laser-Cut The Casting Container:

• I designed and laser cut an adjustable press-fit box to place the individual urethane molds in order to cast the TARDIS in hydrostone. (I also custom-cut shims to key in the urethane mold edges.)

Putting Together the Casting Container / Aligning the Mold:

• When casting, I did my best to align the sides and roof together at the appropriate angles and hoped for the best. An additional laser-cut box with an empty pen casing was inserted into the larger mold when pouring the hydrostone in order to create a cavity for the wires to run form the LED on the top through the cast down into the base where the wiring, battery and other components are housed. The inside box then became part of the cast.

Removing the Casting Container:

• When taking apart the mold, I found that some of the fine details of the windows and the moldings became stuck in the urethane mold or broke off easily. I may not have mixed the hydrostone long enough, or there may have been an issue with the proportions I used. Further experimentation is this matter is needed to determine the source of the problem. This breaking away of the fine detail gave the statuette a weathered appearance, like a tombstone left out in the elements.

Adding the Electrical Components:

• In addition - I wanted to have a LED light on the top to simulate the police box light, so when cutting the outside casting box, I cut a congruent interior box (see number 4. pictures above.) This small inside box allows for an open area for the wiring from the LED through the top of the hole in the stone to the battery. The wiring consists of:
• 1 ultra bright white 10 mm LED
• 1 330 ohm resistor
• 1 small switch
• 1 battery connector and a 9V battery
• A few lengths of wire

I dedicate this project to David Tennant for his the excellent portrayal of the 10th Doctor, which has just come to an end. ;-)

Image © BBC

Anna Kaziunas France
[http://www.kaziunas.com]

Everything I've posted here is hereby licensed CC-NC-SA, unless otherwise specified (or, y'know, if it's a derivative work.)

The Fuxamascanner is still in progress, so I did a quick (20 minutes) scan of a drill bit in Dr. Picza just for the lulz.

halfdrill-blender.stl

screen /dev/ttyS0 Hitting c seems to clear things, o goes to origin, and s begins scanning. No useful output yet, portmon on Windows proved essentially useless, but I have a full log of a picza scanning session in Windows as well.

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Using bazaar with the fab academy repository
This tutorial doesn't have the server setup part like the previous one did, and goes a bit more into managing files.

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I am still working on my Fab Academy 3D Molding and Casting project (a 3D model and cast of the TARDIS. The implementation of my model proved complicated.

Starting with the cad.py created .rml files (for details on the 3D modeling process see my TARDIS: 3D Modeling post), I carved several molds out a block of machinable wax using the Modela milling machine.

Wax Molds

There were a few mishaps creating these molds. The z-max setting was not high enough on the side mold (you can see where the Modela bit drug through the wax and made lines that were not part of the design.). I learned that it pays to set the z-max close to the max of 1 so that it will clear the edges of the design. However, because this particular design took so long to mill out , 7 hours or so, I opted not to redo it if the damage was minor. Instead, I attempted to repair the damaged areas with wax.

After I made the wax molds, I made casts of each side and the roof using urethane rubber. The door was cast once, but the side needed to be cast 3 times to create the 3D object.

I did not allow for space at the top of the wax molds, so to ensure that the rubber would have enough room to capture the top of the design, I laser-cut some tempered masonite frames in to increase the vertical space for the rubber to fill. These frames also make it a little easier to get the rubber out of the mold. (Credit for the frame idea goes to Elliot Smith - he used this technique on his Moon Crater mold and cast).

Creating and Gluing the Frames

Mixing Urethane / Creating the Molds

At Fab Academy Providence, we used a smooth-on 2 part urethane mold mix. Just mix equal parts of each container (A and B) and mix slowly in a figure eight pattern to minimize the bubbles.

What I learned about this material:

• Mix very thoroughly. Take your time (at least 10 - 15 minutes if you can stand it). The end result will be sticky if the parts are not mixed together well - My first two molds were sticky. (suggested by Neil Gershenfeld)

• Add heat. Heat both accelerates the process and creates a less sticky end product. I used a desk lamp positioned in close proximity to the freshly poured mold. (suggested by Neil Gershenfeld)
• Be careful not to leave the heat on longer than 15 minutes or so and let the wax and rubber cool before removing the rubber mold from the wax.
• I learned the heat lesson the hard way when my mold melted from excessive heat. (see photos below)

Beware of Melting Molds

All The Molds (Good and Bad)

Next Steps:

• Create a box and system for keying in the sides of the police box so it can be cast.
• Get LED, resistor and battery to wire up the light on the top.
• Cast in hydrastone

Anna Kaziunas France
[http://www.kaziunas.com]

When reading through instructables.com, I found a great pattern for a polygon construction kit. I thought I would use it for my first laser cutter / computer controlled cutting project at Fab Academy. The instructable I reviewed is for a plastic lamp shade, but I decided to use playing cards instead and make a construction kit minus the lamp. (Also, the cards are too opaque for a lamp and I didn’t want to take a chance with heat in such a small space.) In the end, I created a sculpture construction kit.

Laser Cutting the Cards:

Putting Together The Construction Kit:

This construction kit shape can be put together to form a variety of shapes.

My Final Construction:

Anna Kaziunas France
[http://www.kaziunas.com]

Published in the MAKE Blog.

Our assignment this time around was to design a circuit board, mill it, and program it in Assembly language. Each student had to become acquainted with the following work flow:

• Designing the board
  
• Machining
  
• Stuffing components
  
• Programming
  

Makeda Stephenson in the Providence Fab Lab

In a Fab Lab, circuit boards are either milled from copper-clad PCB stock or cut on a vinyl cutter from copper tape with conductive adhesive. We try to avoid the etching process in order to limit the used chemistry we have to deal with. Whether etching or cutting, the first step is to choose one of the options for creating a tool path to send to the machine:

1. Draw the circuit as a black and white PNG image and bring it into cad.py for tracing.

2. Draw the circuit using Eagle, a free PCB drafting tool, and export Gerber files, a standard format for PCBs. Gerber files can be converted into PNGs using gerbv or the online tool from circuitpeople.com. Bring the PNGs into cad.py for tracing.

3. Draw the circuit in Eagle and use Eagle's CAM processor to generate mill and drill files that can be sent directly to the machine. This process was described by Marc Boon in a workshop at the Amsterdam Fab Lab in 2008.
   

I designed a boombox in Sketchup and I milled it out on the Modela in hard wax, using a 1/16" bit. I like how the tool path left a fine pattern on the surface. This model radio measures 3.5" across, and it began as a block recycled from scrap bits of wax, hence the air bubbles and the stray chunk of wood on the upper right edge.

My year project will be a diorama of a mechanical dance party on a base, and the ceiling above the dance floor will be a functioning record player. The moving figures and the record player will all work on the same motor. I'll be casting these boomboxes in different materials to position around the diorama.

This article was written for the MAKE Magazine blog.

Since October of 2009, a handful of small groups of students have been taking part in an educational experiment called the Fab Academy. The Fab Academy is a distance learning collaborative that's built on the infrastructure of the Fab Lab network. Labs in Spain, Iceland, Kenya, Amsterdam, India, and Rhode Island participate in Wednesday morning lectures by videoconference. The curriculum is concentrated into two week topics with a project due at the end of each and a more ambitious annual project due at the end of the year. This series of articles for the Make: Online will follow each of the two week sessions in the curriculum and highlight the work, tools, and techniques being developed in the pilot year of the Fab Academy.

All the endmills are now in this cigar box, which lives near the Modela. Grab the SVG file for the insert here.

My press-fit construction kit:

The parts have come out! Here they are separate:

Attempting to cast one out of urethane plastic with a layer of soap scum failed, as I hadn't mixed the plastic enough and weird white blobs of goo got stuck in the mold. I'm currently making another mold from the wax original after having stuck the bit that came off back on.

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I've been in L.A. for about a week now and I'm really eager to get back to the lab. I have so many ideas about how to incorporate every lesson thus far into my big project, especially making molds to cast multiples of tiny body parts for the characters I've been sculpting. I'll also be molding some 3-D rendered forms. Complicated and interactive automata dioramas!

I hand- sculpted the heads above in Cernit. I flameworked the glass eyes, and the "hair" on the right is made of trochus shells.

Jonathan's machine uses flexible couplings:

Decided to print an "old school rocket" from thingiverse for the lab:

Seen here in front of Jenine's "Providence" sign.

For my final project -- a pinball machine themed on an opera whose libretto is written by monkeys on typewriters -- I want to have a central chorus pit with five or six monkeys on typewriters. This seems like a perfect application for the molding and casting unit. My wife (Jill Colinan) is making the monkeys, so I thought I'd cast the typewriters for this assignment.

The Fluxamacutter is a design for a simple vinyl cutter that satisfies these criteria:

• Inexpensive ($50-$100 in parts)
• All parts can be cut on a 24"x12" laser cutter
• All press-fit construction: minimize hardware fasteners
• No precision parts required: all hardware cheap and widely available
• Arduino-compatible
• Plug-and-play replacement for existing HPGL-speaking cutters

The initial cutter will be able to take 15"-18" rolls, and will be designed to scale to 24" rolls.

After seeing David Carr’s political map relief I was inspired to do something similar. I thought it would be cool to model the Boston skyline. Since I also wanted to see how fine I could get the resolution, I took a jpg, and using the GIMP program, made it a black and white image with 50 colors and then put it through cad. I had it create a file with the following specs:

z min: -.75″

nz: 50 (one pass for each color)

tool size: 1/32

At 20, 20 speed the file was going to take about 12 hours. I was still going to try to cut it but Shawn pointed out to me that our 1/32″ bit didn’t have a long enough shank to cut at -.75″.

I went back, edited the file down to 10 colors and filled in the sky so as to leave just the buildings.

Then I created a .rml file in cad using a 1/16″ bit, .-.5 z min, and 11 nz.

After about 2 passes, the machine did a dramatic z drop and I had to stop it. Shawn suggested that I use more nz steps so I created a new file with 30 steps.

I piped the .rml files directly to the serial port through the command line as the computer thats hooked up to the mini mill has older software.

I piped the .rml files directly to the serial port through the command line as the computer thats hooked up to the mini mill has older software.

My 3D Modeling and Casting project is to make a model of the outside of the TARDIS. I used the scale and dimensions from G. Hartley’s plans to make an 8 inch model TARDIS.

G. Hartley’s Original Plans

I used these plans to create a 3-D model in Google Sketchup

However, as the milling machine cannot carve out negative space, the faces on the sides or the model could not be created. In order to create a machinable mold, I had to take the 3D model apart into three sections: the roof, the front door and a side (3 of the sides are the same).

In addition, I also removed some details that were in the original 3D model, like the light on top of the box and the all of the “Police Box” lettering. The light was not transferring properly into the CAD file and the lettering would be too fine for the bit on the milling machine. (I plan to create a sticker or letter by hand). I also scaled the model down from 8 inches high to 4.8” so it could fit within the block of machinable wax.

Shawn Wallace also suggested that I cast an LED into the model and use it for the light on top of the box. Brilliant.

The Roof, Side Door and Front Door

Sketchup exports .stl ASCII files and I needed them to be in binary. I opened the files in Meshlab and then exported them as .stl binary files. Next I ran the .stl files through stl2png.py to convert the depths to grayscale.

The final result (roof not shown)

The next steps are: 1. Mill out the 3 of the mold pieces 2. Cast with rubber, making 3 casts of the side view 3. Create a laser-cut box that will hold the mold together when it is being cast with hydrastone. 4. Cast with hydrastone.

Anna Kaziunas France
[http://www.kaziunas.com]

Creating a bzr repository:

First, inform bazaar as to your personage:

bzr whoami "Mr. Foo <mrfoo@as220.org>"

Then, make a directory for your repository: mkdir repository

Initialize the repository:

bzr init

Add the current directory:

bzr add *

Make the first commit:

bzr commit -m "Hello World"

Now, every time you want to add files, run

bzr add <files>

again, and

bzr commit -m "Message".

To check out your repository

start an ssh server (openssh-server in ubuntu, check the box in the preferences window in OSX), and run

bzr branch  sftp://user@ip-address/path/to/directory

Then

bzr pull

To update the repository, bzr commit again and then

bzr push

Have fun!

-\n

Elliot and Shawn were debugging the modela, Elliot bet $1 that switching zmin to a negative number wouldn't fix the contouring problem (even though it'd been his suggestion to do so) and then Shawn bet $1 that adding a white background would fix Elliot's contouring problem. Shawn won both bets. I still haven't finished building Jonathan's machine, I cut another threaded rod that was too short, and our chemical filter isn't working. Susan, however, installed a new, quiet fan, so the leafblower has been obsoleted.

-\n

The results of Shawn helping me work through the problem of having multiple button with several positions

I'm making a "Persistence of Vision" toy, which will show a programmed message in eight red light- emitting diodes. In the lab we have a roll of copper foil backed with a conductive adhesive. I used a knife to cut out a hand shape. (In this case, I found it faster to work this way than to use the vinyl cutter.) I covered a small metal container with a vinyl sticker to insulate the foil board from the conductive tin. I soldered some surface mount LEDs and resistors onto the copper.

Here is the hand after I drilled holes through the tin and soldered wires to the fingers. The wire on the bottom is ground.

This is the inside of the tin so far!

Our last module was on computer numerical machining and the assignment was to make something big on the ShopBot.

A few years ago, I made these star-shaped boxes on the laser cutter with thin (1/8″) plywood. For this assignment, I thought I’d scale up the design and make a few for my mom.

In my original design I used tension fits to pressfit it together, which was fine on a small scale. As I contemplated the modifications I’d have to make to scale it up, I realized that I’d need to actually model it in 3D and carve angled edges to accommodate the angled corners of a star shape. I did the 3D modeling assignment, but I did it in SketchUp because I didn’t have the time to become sufficiently competent in Blender.

Eliot, (one of the student in my class) hadn’t completed the 3D assignment so he made a model in Blender and carved it on the ShopBot. I figured I could do the same with my project and become proficient (sortof at least) in a more conventional 3D modeling environment while completing my CNC machining assignment.

Not so fast.

It was the middle of the first week before I reached a solid decision. (I was still working on hacking parts for our PCB Fab assignment from the previous module…aahhh.) After seeing what Eliot was doing and playing around a little bit I decided that this could only be so hard. Thats true of course, but “only so hard” turned out to be about 4 times more confusing than I had thought.

We played around with the program, completely ignoring the “extrude” tool for the first couple of days in favor of an agonizingly complex and excruciatingly inefficient combination of {select-push/pull-cut-delete-create face-face is warped-cut again-delete extra faces and edges-it looks good-no its skewed-cut-my brain is now crashing} rinse and repeat as many times as needed… method.

By the time we found our good friend “extrude” again, it was Friday. I planned to work on it over the weekend. Not surprisingly by Monday, one crazy weekend and two non-supportive computers later, there was no virtual star-shelf to be ushered into the analog world.

Shawn agreed to come up to the Boston lab to help me with the ShopBot on Tuesday. Switching to crisis mode I decided to make a sign for our lab instead.

When Shawn arrived in Boston I had an Inkscape file ready to cut.

I printed this on the shopbot but the pieces are still at Keeseh so I'ven't been able to test it yet.

skateboard.svg

I opened it in illustrator and saved it as an eps, opened it in partsworks and it cut fine.

I'll post attempts to assemble when I get the actual parts.

-\n

I designed some shelves and cut them out on a Shopbot. While working, all pieces have to be secured to the bed of the machine (or to each other) because the tool is so powerful that the router could send a loose piece flying and seriously hurt someone.

I screwed my 4' x 8' sheet of MDO (medium density overlaid plywood) to the bed of the machine, and we programmed it to cut tabs between some of the parts so they would remain attached to each other. The finished sheet resembled a plastic toy whose tabbed pieces would be broken apart and snap assembled.

Here are some of the shelves after being cut on the Shopbot, and broken apart with a jigsaw.

Thanks to the Avineris for letting me borrow a palm sander. I used it to sand the tabs off the edges of the shelves.

I primed, painted, and installed the shelves in a corner.

I have more shelf pieces cut, but I haven't yet decided where to install them. Photos of my pieces on the Shopbot at Keeseh Studios will be posted after the holiday.

FELT

First attempt in felt:

I'm working on creating an chording keyboard

http://en.wikipedia.org/wiki/Chorded_keyboard

for my final project. Hopefully I'll be able to use the skills I learn in the FAB Academy to make one that actually works.

These packages are all in the Ubuntu repositories, so it's reasonable and sane to run:

aptitude install inkscape blender qcad python-scipy python-numpy python-tk python-imaging-tk eagle curl

We mirror http://fab.cba.mit.edu/about/fab/hello/ and http://fab.cba.mit.edu/about/fab/dist/ using Curlmirror. (a perl script that spiders webpages)

Some of the boards were coming out a bit hairy due to our initial use of the wrong drill bit (we were using series 1 when we need 1b), so I made a hairy hello world .cad file: hairy.button.45.cad

All attempts to create a working board without ripping off the traces or shorting out important pins have thus far been nonexistent, however, this may change shortly as Elliot's just milled a fresh batch.

I constructed this ruffle beard from fabrics that I lasercut and hand- painted. I wear it while biking to keep my face warm.

I drew these shapes, lasercut them, and assembled them into jointed figures. The joints consist simply of short pieces of bent wire.

This is a sheet of lasercut pieces for the jointed figures. The material is matboard from a frame shop.

This is a press- fit swingset that I lasercut from 1/4" thick wood.

I drew these shapes on a computer with a mouse, which took a very long time and hurt my wrist. I am investing in a tablet so I can draw more comfortably on the computer.

Hey hey hey Fabulous Folk! Welcome to the virtual expose of my fourth Fab Academy assignment.



For assignment #4 we were asked to create a press fit construction kit. My form and function goal was a basic set of pieces that would allow freeform construction of almost any shape.

Check it out :)

A Series of un-Unfortunate Events

I tested my initial idea in matteboard and found the combination of strength and flexibility well suited for my project. I wanted to play around with thin plastics but ruled out acrylic because it's too brittle. There were a couple scrap pieces of this white bendy plastic lying around the lab so I thought I'd try it. It worked like a charm. :) Upon further investigation I learned it's called Delrin. Delrin is an industrial strength plastic thats easy to lasercut and is used for stamps.

I originally created my design for a .05" thickness material. The Delrin sheet I had is .06" thick so it fit very well. Also we had some bugs in the laser cutter settings so it perforated the entire design instead of cutting it through. This actually turned out really well in the end because when I finally got it cut, the perforations acted as little "teeth" making the joints that much stronger.

I made a bit of a tradeoff in my design between ease of assembly and structural integrity. I intentionally offset the slots from the center so as not to compromise the center of the reed pieces which seems to already be a natural stress point. I'd like to do a little bit more research to see if this tradeoff is actually necessary.

GIK city invaded by Metabrick monster.

There wasn't a script to fetch the dependencies required by cad.py under ubuntu, so here's one: fetchdeps.sh And there wasn't an SVG of GIK, so I ran it through trace bitmap: gik.svg

Row row, fight da powa.
These were tinted red with a Bic permanent marker.
kaminaglasses.svg

Art of Illusion is messy, here's how to make a window frame. window.stl

ganked mostly from this tutorial

This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 3.0 United States License.

A bunch of thin strips, 1pt or so apart, vp=5 vf=700 vs=100, make a sort of crude set of sunglasses.

This is 3D model of box I made in Art of Illusion, my semester project is a hydration bag, like the kind you find on lifeboats, that works via osmotic desalination. It's currently an extremely crude rough-draft type thing, but I think it gives a general idea of shape. The filter will have 30nm holes and be made of teflon. box.stl

SketchUp models of my robot arm...

Pinball machines need a lot of coils. I realized that my first step in creating a pinball machine would be to build a tool to wind accurate coils. The pinball machine hobbyist scene is pretty well organized, so I quickly found this chart at pinballmedic.net detailing the various coil winding schemes that I will need:

Coil chart at pinballmedic.net

I've begun a little later than everyone else, and I think I have less experience with most things electronic. Fortunately, I'm eager to learn and I can usually pick things up quickly.

My current plan for a semester project is to make a very detailed diorama, employing motors, sensors, cutting techniques, and other approaches to familiarize myself with what is possible, and to build facility with my new skills.

I have a strong background in traditional crafts (glass, textiles, metals, clay. . .) and I make dolls and puppets. I flamework glass eyes and glass teeth, sculpt the faces and bodies in polymer clay (often sculpting with sewing needles because they are so tiny!) I make the wigs, sew the clothes (I spun flax into yarn and knit the dress pictured above.) I love the idea of integrating my customary practices with new ways of working and thinking. How exciting!

Project #2: A machine that looks for inspiration from 18th century automatons (again), Mary Shelly, H.P. Lovecraft, and my fourth grade science teacher Mrs. Snabon.

So I need a proposed semester project ready to present to the world in less than 48 hrs... Do I sound stressed? The nice part is, I already have a project :) and you are going to help me with the presentation!

Today I'll be taking up just a little bit of space on the web to tell you about the results of a system of "mindstorms" which have bombarded my brain since you last heard from me.

Here it goes:

Occasionally I suffer from a severe lack of creative thinking. One of these spells perfectly coordinated its arrival with the second week of Fab Academy.

I wanted to do a cool artistic project but was having trouble coming up with concrete ideas. At the same time, I was really intrigued with the topic of the first week's assignment: artificial self-reproduction. Last week they asked us to conceptualize a self reproducing machine. My idea was based on integrating robotics with CNC machining technology.

I finally decided on a compromise. I would like to attempt a basic demonstrative model of the first assignment and add an artistic twist.

I'd like to build a robotic arm that would be programed to build a structure out of blocks. The blocks would somehow interact with the robot to aid it in building the structure. I'd like to keep the materials used in building the robot and the blocks as simple as possible. My goal is to illustrate the idea that the parts for a machine can be built and assembled in the same system.

As far as the artistic part goes, I want the blocks to give some sort of cool audio/visual feedback.

Wish me luck!

Graphics coming soon! :)

9/30/09- simple model

This post illustrates my initial thoughts about embracing the possible anomalies and ugly ducklings that may come with self-replication.

Ok, so now its not enough to be able to make almost anything- or to be able to make something that can make almost anything. Now you want something that can make its self, virtually unassisted? You humans are never satisfied... Oh wait, thats me too. Well, why should we be satisfied if we don't have to be? I'd like to share some of my thoughts on this week's assignment: design and document a self-reproducing machine.

It is true that the ability to reproduce ones self is an organic quality of living creatures, fundamental to our continued existence and not inherent in the absence of life. However, researchers have successfully demonstrated artificial self-reproduction in mechanical machines.

During my limited research on this topic, I noticed that most of our modern self-replicating machines are assembled out of completed modules and do little more than reproduce. The more practical self-replication projects have the capacity to make various objects, including parts of themselves but are not yet completely self-replicating.
Here I'd like to briefly discuss my ideas for a machine, capable of complete self-reproduction.

I would propose combining Computer Numerical Control (CNC) fabrication technologies with robotics to achieve a system which would:

• build a child machine in modules using fabrication technology
• assemble those modules into a working replica of itself and
• finally transfer a copy of its own self-replication program into the now complete child machine

This child machine would then be able to to build grand-child machines. The "genetic code" for reproduction of this machine would include CNC design files for each required module and the robotic assembly program. The entire reproduction process would be completed with minimal human intervention.

CNC fabrication technologies have allowed us to build just about anything at small and large scales and in various materials. Utilizing this technology in a self-reproducing system would eliminate the need to supply pre-completed modules and reduce (though not eliminate) human involvement.

As the modules for the new machine are completed, robotic arms would configure them into a child machine. The robot would be controlled by a time sequence and data collected from contact events occurring during the construction of the child machine.

This post describes and documents a simple machine that can replicate itself. As with any self replicating process, the major limiting factors and design decisions are:

• The method of supplying raw material
• How to seed or start the process
• How to represent the code that controls the process
• How state transitions and signals are communicated
• How to represent a mechanism abstractly that does not require magic or alien technology to realize
• The utility of the final thing

I started the design process thinking about ways a machine can piggyback on biological processes (e.g. a tree) to provide the raw material and base for replication. Kind of like automated topiary, not unlike a topiary chair.