Friday, September 30, 2011

NyanCAD: Correct motivation for learning CAD

I'm embarrassed to say how many hours I've wasted CADing nyancat paperweight for 2.008 now.
Off to go spend even more time producing CNC mill G-code using Mastercam for a machining appointment at 8am o__o

10/1/11 Edit:
Aha, so I realized (thanks to Steve, shop instructor extraordinaire) that there are many things wrong with my CAD. Sadly, I chose 5 mils spacing for the grid I used to trace nyancat. Turns out our smallest drill bit is 1/16'' ( over 6 mils). Eheh. Also, I was planning on going 0.3'' deep, which would take forever to mill out using 1/16'', as it can only go ~0.02'' down per z-axis pass.
yea, milling fail.
that, dear friends, is the look of a lot of milling time.
I was halfway through the infuriating MASTERCAM too. Lesson learned: avoid branching as much as possible. See that right-most sprinkle that touches the cat's head? Caused me no end of trouble!

Next step? Infinite Mastercam'ing. Instead of being a nice cavity with extruded nyancat, it'll probably end up being closer to pedestal with a nyancat on top done in thin layers. I'll also use a larger diameter tool to pocket out each shape and then contour with the 1/16''. So, first up, redo solidworks using 0.7'' grid spacing (resize reference picture accordingly -- btw, found under insert > sketch tools > sketch picture).

I'll stick the files up on github sometime soon.

=====
Todo this weekend:
Saturday: Get ISP and PoV working, 6.131 lab writeup, MITERS misc. (project grants / safety / update website), PoV with partner 10am, Theater scene practice 2pm. Apply to summer jobs.
Sunday: 6.131 lab (1pm to midnight), 2.008 group meeting 7pm, watch a play (3 pm), go visit Sprout? (2pm)
Monday morning: lasercut cookies, document cookies and ISP.
Oh yea, speaking of ISP programmers, this week's assignment was to mill ISPs using these desktop Roland Modela 3d mills:
So someone made an even tinier one that doesn't need a USB connector (fits right into the slot): http://bardagjy.com/?p=628
Then someone riffed off of that and made one that has a break-off part for bootloading the chip:
http://fab.cba.mit.edu/classes/MAS.863/people/valentin.heun/2.htm
Posted by nrobot at Friday, September 30, 2011 0 comments
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Machine Shop Safety: Yale and the Missing White Woman Syndrome

MITERS is a student shop on MIT's campus. Funding-wise, we run independently of any MIT department, which is great since our projects don't exactly fall into research all of the time. We also don't have to pay rent or utilities due to being located on MIT property. However, this also means that for better or for worse we are subject to the scrutiny of MIT's space administrators and Environmental Health and Safety staff.

MITERS runs a delicate balancing act that, for me, strikes home two contrasting trends: increasing paranoia (and safety) over the years (perhaps best dramatized by 9/11 and Homeland Security), and increased interest in the amorphous idea of the "maker movement." I am torn. Sometimes I am skeptical; Traffic mentions that the number of deaths from parachutes leveled off and has remained constant despite increased safety measures; what happened was that better safety measures made people comfortable with taking greater risks. Sometimes I am cautious; Traffic also mentions that we are all overconfident drivers, believing the past predicts the future as we confidently take to the roads (one study showed that ambulance drivers, because of the urgency of their mission and contrary to what many would think, actually drove "better" -- turning sooner and driving more smoothly -- than the average driver).

Recently, the Yale death (I apologize to those still in mourning for this crass mention) has lead to scrutiny of the sort that makes all of us at MITERS a bit uncomfortable. Our machine tools are old and no one would mind a newer mill or lathe or better safeguards. However, we all seem to feel instinctively that too much scrutiny on any level is toxic to the creative haven of MITERS (and dear lord, apparently a ton of grad students will be moving into our building which will be fit for the Prime Minister of Singapore to look upon within a year or two -- that'll be interesting, but no point in worrying just yet). In reaction, my fellow MITERS officer Julian Merrick remarked that this situation seems reminiscent of Missing White Woman Syndrome, where there is a disproportionate reaction to unfortunate cases involving people of one class (white and female) as opposed to another (male, other ethnicity). Indeed, a google search turns up a thread on Practical Machinist remarking the same.

One surprising constant throughout the ongoing whole process, however, has been people's appreciation of the output of MITERS. Uniformly, people have been supportive of MITERS, even if we may have different ideas of the kind of support needed. Ultimately, I am hopeful that we will emerge through this with better safety and our core culture intact.
Posted by nrobot at Friday, September 30, 2011 0 comments
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Wednesday, September 21, 2011

Ideas: PoV Yoyo, Press-fit food || Classes, Spring 2011

Mmmmm.... classes.
Started out with:
2.008 (Make a yoyo)
6.131 (Power electronics)
6.042 (Math for CS majors)
6.003 (Signals and Systems)
6.004 (Computation Structures)
Some HASS class

Now:
2.008 (Make a LED persistence of vision yoyo)
6.131 (Power electronics)
MAS.863 (How to make almost anything)
21M.611 (Foundations of Theater)
Possibly either 6.003 or 6.004, still.

In other words, I was ecstatic when I heard I got into MAS.863 and that flipped me in favor of not double-majoring in 2 and 6 (unless I decide to take an extra semester or something).

==mas.863==
Our first assignment:
Trying to think of interesting new ideas, I thought of pressfitting food (sparked by my interest in etching poptarts for nyancat poptart). The hunt for a suitable material is on...
Gingerbread recipe: http://homecooking.about.com/od/cookierecipes/r/blcookie111.htm
Other house-building person: http://web.mit.edu/newsoffice/2008/arch-sass-0703.html, http://cba.mit.edu/events/10.08.FAB6/Sass.pdf
Other materials guy: http://web.mit.edu/bin/cgicso?options=general&query=bredt came up with powder solution for 3d printing

(Other people's projects, which overlapped with some of my other ideas:

General Prettiness:


===2.008===

In the meantime, I've also been ignoring the present day and contemplating the near future of 2.008. I think we're supposed to be making paperweight designs or something, but my partner is a but hard to contact, so I've fallen back on daydreaming about LED persistence-of-vision yoyo's. Doesn't seem to have been done already, surprisitngly. And now for linkspam research:

PoV
Other products
DIY
Yoyo
2.008 Yoyos
In order of awesomeness / completeness of online documentation:

Youtube videos:
==misc.===
RFID tags idea: oohh, someone in a previous 863 class had a similar idea for not forgetting things. Or rather, exact 
passive, duct tape + magnet wire: http://scanlime.org/2011/05/duct-tape-rfid-tag-1/
Posted by nrobot at Wednesday, September 21, 2011 1 comments
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Thursday, September 15, 2011

Summer: Rideable hexapod, check

teaser pic
Ah, where've I been all summer?

Having lots of fun, actually, but I've been hiding in my codefail cave and then I went and lost my camera.

Poof, hundreds of meticulous documentation pictures. Serves me right for not documenting as I go along / backing up my pictures.

Above is a pic of hexapod before I added the foot controls. Which are now being demoted in favor of joystick controls. But I did finish it in time for dorm rush / hall rush and gave lots of froshlings rides! And discovered some serious issues :)

Hexarideablepod is based off of a very detailed instructables called Hexabot. I'm slightly embarrassed by this fact, for whatever reason, and even though hexarideablepod only deserves my love (it already has my blood, sweat, and tears...)

Yea, that's a racecar seat that my fellow MITERSians helped me recycle from an old unfinished vehicle :)
Posted by nrobot at Thursday, September 15, 2011 0 comments
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