asia trip: in the beginning there was lots of traveling

OH DEAR LORD WHY AM I SO BEHIND ON BLOGGING
anyway

so we took lucky star bus out, ...
went to seatlle, had dinner with cathy's family (well, her mom and younger brother) and jason, her friend from high school -- no pics because i hadn't turned asian mode deflect all embarrassment on yet, but expect some from cathy

... so we stayed a night in seattle, which was very foggy and very green and cold but not terribly so

the next day we got up and had delicious scallion pancakes courtesy of cathy's mom and then we set out for the airport to try again

well, there were 100+ seats yet still until ten minutes before the flight should be taking off, they'd let no standby on due to the problems getting an accurate weight estimate (were they turning it into a cargo plane? or just fail on some software package?)... some people had been there 3 or 4 days, which alarmed my friends >__> anyway they cleared all 40 or so standby in the end, including us, and delayed the flight just to get us all on. yay.

13 hours later we arrived in japan. ignore the datestamps, they're all screwed up.

then we used the toilets in Japan. i was amused because i'd been reading about the japanese toilet revolution courtesy of the big necessity, a book i picked up @ mit loading dock sale this term and really like (still working my way through). we also awarded kudos to the sink design.

look how many functions they have!

vending machine / start of epic asia trip

well speed update
made cardboard proto of vending machine, final project of mas.863

then CAD'd and emergency lasercut one, but still didn't have time to do electronics :/ (buttons are just stuck on there, and i didn't leave space to route servo wires, and i'm using janky self-made continuous rotation servos / zip tie couplers to springs

but first time really CADing the full thing before creating it! compare hexa-not-quite-dancingpod, which was cut by hand and then CAD'd

anyway, open house happened, then I emergency packed and we took T Red line > south station > lucky star bus to NYC (11:30 pm) ... arrive around 4 am and take J nyc metro to JFK airport.

derp! didn't get on flight seattle > narita, (yay standby) due to some weight balancing fail. (flight left with 34 empty seats)

that's okay, we got to meet cathy's family! (cathywu.posterous.com)

well got on next day

ack! have to get on flight narita > taiwan now.

[edit: for more updates on vending machine, see: http://orangenarwhals.blogspot.com/search/label/vendingmachine]

emergency motor controller fail

just an update to say no, i did not successfully make a motor controller in 48 hours :)
(see previous post for schematic: http://orangenarwhals.blogspot.com/2011/12/eagle-persistent-hotkeys-emergency-h.html)
what was it? a 6.131 final project / motor controller for hexarideablepod (derived off of an instructables):

which works, but uses an arduino and two victor speed controllers -- total overkill. also, terrible UI: it uses a hard to reach switch for fwd/bwd and foot pedals, which little kids have issues reaching even with the awesome!adjustable-car-seat.

block diagrams! ewww.

https://github.com/nouyang/hexapodtroller for the eagle sch/brd. You can see terrible routing here:

power board (4 FETs to make a full H-bridge)

sig board -- attiny44 and four FET drivers (21844s). also, chain voltage regulators from 24v battery to 15v for drivers to 5v for attiny logic.

speed routing and my inexperience led to use of 24 zero ohm resistors and I still used a jumper :)

hai zero ohm resistor friends

If you look closely, you can see some of the trace fails (compare IRL to board layout) which were probably due to too high error allowances when the fab module was creating the roland modela machine code. See: pins 8 and 9 on the top right side of the topmost IC, the attiny44. They're connected on the board but not on the schematic. I used eagle's erc/drc and it didn't point out a warning so I'm going to assume it was mill code generation settings, not limits of mill capability.

I discovered how useful eagle layers are, even in the interface is terribly clunky.

I create zero-ohm resistors a dumb way that actually turns out to be helpful when populating a lot of them. Since they each have an air wire, I can set air wires to a nice contrasting color and see where they all are:

Another note, I milled out the moles CNC-ly too using GIMP to get the traces I needed, but :/ milled them out too small and had difficulty getting the 3.5mm spacing power connectors to go through the board -- had to carefully use a vise.

This is what the final half-populated boards looked like: