Tag Archives: asia trip

Uncategorized

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://www.orangenarwhals.com/?p=152)
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:

Uncategorized

China Makerspaces Visit Planning

1 Comment

I’m hoping to / planning on visiting Chinese makerspaces between end of term (12/19 for me, as I have not finals) and IAP (January 9).
[last updated: 11/24/2011]

http://hackerspaces.org/wiki/China
Shanghai

Shenzhen

  •   www.chaihuo.org, active as of november 2011
    • Saturdays, 14:00 – 16:30 (gcal sidebar)
    • ch.makerspace, g.com
  •   SZDIY (shenzhen diy lab) active as of today november
    • 聚会Every Thursday / 每周四 19:00～22:00
    • 答：Seeedstudio 是深圳创客空间（Chaihuo）的主要赞助商，Chaihuo与SZDIY目前达成协议在特定时间（每周四晚）免费提供聚会场地给SZDIY社区使用来举办固定聚会
    • szdiyadm, g.com
  • http://wikitravel.org/en/Shenzhen

Beijing

  •   http://bjmakerspace.com/ (both flamingoeda and gkfab have been subsumed by this, active as of october EDIT 11/24 active.)
    • meetings every Tuesday 20:00 to 22:00 (http://www.bjmakerspace.com/Event.html)
    • open every day (according to email correspondence 22 nov 2011)
    • http://space.flamingoeda.com/ (last update july)
    • GKFab (not alive?)
    • We have weekly meeting at Tuesday night, and workshops at weekend. The space is opened every day, and you may want send us a mail before you come so we can make sure there is some members in the space
    • bjmakerspace, g.com
  • yff — not sure if it’s actual makerspace looks corporate or spam. 

Guangzhou:

  • hackerspaces@gz (1 member?)
  • HTG (not active since 2010)
So looks like I should try to make Shanghai and Shenzhen, possibly Beijing although that’s covering a lot of ground in a week (mmm transportation costs). Guangzhou ones seem dead, which is a pity since that’s actually close to Shenzhen.

==
http://www.seeedstudio.com/blog/2011/10/16/first-open-hardware-gathering-in-china/
Ooh look! Someone I know is there! Star Simpson is apparently in China until January or so. And Maja Wichrowska (roomies shoutout!) is in Beijing for the semester. o.o Whoa. A lot of people I know are in China…
===
http://hackerspaces.org/wiki/Call-inJan 1st, 1600 EST
===
http://hackerspaces.org/wiki/Japan

  • kubotaa@tamabi.ac.jp (no response, dec 2011)
  • info@456.im (no response, dec 2011)
  • Tokyo hackerspace (contacted via form):
    • Tokyo HackerSpace has an open meeting every Tuesday night, from 7 PM. 
    • Unlike most other hackerspaces, our members have very little free time, and as such, the space is not in constant use. Our members have a key, and can come any time they like, but its hard to predict when that will be.
    • I would highly suggest that you join our google group and introduce yourself and your schedule there: http://groups.google.com/group/tokyohackerspace You’ll have a better chance at finding what everyone is up to, and when they can meet up.

http://hackerspaces.org/wiki/China
? None in Taiwan nor Korea.
===
Visas and Passport Renewal
Proxy Chinese Visa service: http://ask.metafilter.com/95095/Visa-service-recommendations e.g. http://china.visahq.com/ (also does passport, also well-designed site)
Emergency Passport-ness: http://travel.state.gov/passport/npic/schedule/schedule_852.html

Boston-specific:
I found a local Chinese company helping with visa application:
国际文化旅游公司
Cambridge
617-868-3096
最便宜的机票+最优质的服务$170 total /1 year multiple entry。 If you fill out the form. Sounds reasonable. close to what they charge here.It is close to T. ~5 walking from T station. 2 stops from harvard (outbound).Go to the web site, fill out the file and print out. take 1 2×2 picture, the passport valid for 6 month and blank page .
经纬旅游 Boston 617-426-3123
===
electronicky shanzhai 山寨
http://www.bunniestudios.com/blog/?p=284
and also awesome book:
http://craphound.com/ftw/download/ which is a fantastic romp around gaming culture, economics, and unions.
more on shanzhai
http://www.tigoe.net/blog/category/environment/295/#more-295
more on shenzhen http://www.evilmadscientist.com/article.php/shenzhen
the linked article is account-walled so here is the article http://www.strategy-business.com/article/09315?pg=all&tid=27782251

===
personal

1 Transportation FCU
 55 Broadway
Cambridge, MA 02142
Driving Directions
 Send to Phone		 ATM
Deposit-Taking
Surcharge-Free

1.16 mi

=== Options: personal tours. Or get MIT departmental backing (talk to Anne Hunter / Brandy Baker) for report publication, go in officially.

=== Oh hey look, someone wrote about MITERS in Chinese.
http://www.chaihuo.org/2011/10/19/%E5%88%9B%E5%AE%A2%E6%94%BB%E7%95%A5-%E4%BB%8Emaker-faire-%E5%88%B0mit-4/
“not the game, nor is it the job, just love” Thanks, google translate 🙂

===
update 2 dec 2011
according to David of shanghai’s xinchejian, There are current 4 in China. OnionCapsule in Hangzhou is the first student lead hackerspace in the China Academy of Fine Art by a group of new media art students. They have a public performance scheduled on Dec 24. If visiting hackerspaces is one of the goal of your trip, I’d suggest you visit them at this event. It’s crazy party and a lot of fun.