here's a flickr set for this bot
flickr.com/photos/sixmilliondollardan/sets/72157616240288122/

the zip file is a bunch of solidworks files. SW2006 i think. but i can't remember exactly. i will try to find my parts spreadsheet and toss that up as well.

Spring 2008.
I designed and built a simple torso for a Go playing(manipulation driven, not strategy) robot for Prof Rod Brooks at MIT CSAIL. Postdoc Eduardo Torres-Jara works on the motor drivers, control, and hand design. Josh Kargas did some of the electronics mounting and routing.

Robot has 6 Series Elastic Actuator degrees of freedom. But waist is locked out and shoulder joints have the spring shorted out.

DOFS:
waist yaw
shoulder x 2
elbow x 2
wrist vertical axis x 1
wrist rotation axis x 1
neck pitch x 1
head tilt x 1
head pan x 1

yes analog sensors. potentiometers are awesome.

My Second design of a small geometric sculpture that explores the battle between cake and pie

This is a thermal barrier retainer block I designed for my plastruder to replace the stock retainer washer, steel washer & m3 screw stack. I also use this block to mount the plastruder to my z-stage so that's why the block is kind of long. One surface of the block is flush with the back of the plastruder housing and has two M4 threaded holes.

This is a project I've been needing for a long time. When I use my CNC router table I would just layout my cutting tools. Most of the time they would roll around or fall on the floor. With the tool holder I place all of my tools, collets, and I can place the tools I need in the order I will need them in. This is the first step. The second step is to make an arm and attach it to the computer stand down tube.

Using 3 pieces of acrylic, 1 6inch by 6 inch board and 25 to 30 220ohm resistors i made this heater plate. you can make it too! -

i soldered one end of the resistors to the copper board, applied a thin layer of tape to the area across that was not soldered, and then soldered the other end to a wire . the red wire was positive, the copper plate was negative, i then soldered the copper board with a black wire, and then taped several times over the copper side with the resistors several times to allow heat to stay in. using the resistor values is ok, a method that uses 330ohms is used to keep telescopes from fogging at night. the idea is to provide enough energy in heat that can be dissipated safely. the soldered end of the resistor transfers heat to the copper board. the copper acts as a heat spreader, and the pcb acts as a good stick layer for thermal plastic. I also have a video here:
youtube.com/watch?v=pDEkp3ym1TE

Our idler wheel kept cracking so we made one out of aluminum. Works great!

The waxuum is sort of a reverse-extruder. The idea is that a heated hollow needle is used to remove material from a block of wax in a controlled manner, analogous to conventional machining using an endmill. A vacuum pump* pulls the molten wax through the needle, after which it is deposited in a reservoir where it can be recycled. The wax part can then be used directly, or more likely it can be used as a pattern for a mold. Below is a basic overview of how the process might work in a well-developed system. See video of a simple test at youtube.com/watch?v=rnKD9oIzcnM .

1. A heated basin is filled with wax, which is then allowed to cool. This big block of wax forms the working material for our little setup.

2. A waxuum mounted where the extruder usually goes on your 3D printer carves a master pattern (including containment walls) out of the wax block.

3. Elastomer resin is poured directly into negative pattern in the wax block.

4. When the elastomer cures, it is peeled off the wax master and used as a mold to crank out large numbers of parts.

5. The wax master is remelted within its heated basin. The removed wax in the reservoir is added back. The basin is cooled, and the wax is ready to use again for a new master pattern.

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ADVANTAGES

1. The wax is melted instead of cut, so high forces are not required at the tool-tip. The low force requirement means that the XYZ positioner can be much more flexible (and cheaper and easier-to-make) than is normally required for conventional machining. Unlike conventional machining, there is no need for chip removal.

2. In many cases the surface finish on parts is better than that on filament-extruded parts, due to the smoothing effect of the hot needle moving over the wax. There are also fewer warping, delamination, and anisotropy problems.

3. You get a mold instead of a part: casting from a pattern can produce parts at a much faster rate than printing. You also have a greater choice of materials (plastics, metals, ceramics, and wax can all be cast in silicone molds).

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DISADVANTAGES

1. You get a mold instead of a part: there are several additional steps and materials, including the manual work of pouring resins. Sometimes you really want to just print your parts and go.

2. Limited geometry: unless you make multi-part molds with cores and such, you are limited to relatively simple geometry. Hollow and concave parts are difficult.

3. The waxuum is relatively unproven compared to the many filament extruder designs currently in use.

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RESULTS

The test showed it was feasible to use a tool of this design to make wax patterns. The most important thing to consider seems to be optimizing heat transfer from the needle to the wax, while minimizing heat loss due to movement of cool air through the needle. The thin-walled brass tubing is just barely acceptable for this purpose. The next version will use a material with higher thermal conductivity, such as thick-walled copper tubing. The heater should probably be located outside of the case. Possibly two heaters should be used - one for the needle and one to keep the wax molten inside the case.

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*Update March 6 2010: See this cool article on converting an aquarium pump to a vacuum pump garage-shoppe.com/wordpress/?p=109

I'm trying to modify some aluminium profile (Bosch Rexroth, but 80/20 is similar) for use as a heatsink for 4x Pololu stepper motor driver boards. It may or may not work as planned!

I got sick of trying to use my drill press as a lathe in my attempts to build my extruder, so I threw this together in SolidWorks. I used 1/4" and 3/8" acrylic for most of it. There are three pieces of 3/4" HDPE for slides. It has 12 X 1/4-20 hex nuts, 36" of 1/4-20 threaded rod, two plastic knobs, and the drive assembly from a cordless drill. I left off the tailstock, live center, and cutting tool plate, but those can be easily fabricated. Use it at your own risk. I uploaded some pictures of the finished lathe and my first completely successful part. The lathe isn't the perfect solution, but it get's the job done.

This is a blocky bike stem. We machine them out of 7075 aluminum. Check out cwandt.com/blockhead-stem/

This sliding shade straps to your vehicle's sun visor. The shade extends to block the sun from your eyes when the visor is not long enough.

This is a small hook designed to be used to hold coils of line (boat speak for rope). We have some similar devices on our sailboat, but they don't work too well, so I designed these.

Mendel Acrylic Build Platform with holes for MakerBot Heated Build Platform

I'm embarrased to say I forgot to measure it before I installed it. Tired of breaking my acrylic idlers, I had my father help me rig this up in his machine shop. Yes, it's been done before, but it's SUCH a better solution. I'll upload the measurements at a later point, like the next time I have to rebuild the head. Which is hopefully never.

Parametric sprocket for various roller-chain or catepillar-track drive applications.

Update: generated STL file for bicycle front sprocket with these parameters (measurements in inches):
sprocket(34,0.312,0.5,0.12,0.001);

This is the new "Smooth rod holders" I created to hold my bigger 10mm smooth rods for the Y axis.

The mounts is made in aluminium and are pretty quick and easy to make.

A simple 6mm thick Heated Build Platform. This was designed to make my ToM more reliable. As I have been dialing in the Z height more accurately recently I have encountered issues due to slight warping of the HBP's PCB and have had a few occasions where this has resulted in failed prints, removal of Kapton tape from the HBP surface and damage to the HBP itself. As I increasingly leave the printer to do its thing unsupervised and place it in the hands of others I wanted a more reliable surface to ease my mind. Designed in 5 minutes in AutoCAD using the ToM's laser cut acrylic build surface CAD files from here thingiverse.com/thing:4973 and featuring countersunk holes on both sides for 6x M3 machine screws and filleted edges all around. I hope to use this as the base of a new ABP I am working on in future too.

This is a fork
You can Eat with it
You can stab things with it
You can launch it with a device made to launch such objects


This thing has changed the world, can you?

This is a fork
You can Eat with it
You can stab things with it
You can launch it with a device made to launch such objects


This thing has changed the world, can you?

A camera mount to fit web cams on the MakerBot so that timelaspes can be made of the parts that are printed. This mount sits in place of the front pannel of the HBP.