Link Dump / Robotics Inspiration

I recently attended most of a (telecast) lecture by Andrew Ng. The lecture was primarily about various algorithms used to control STAIR. STAIR uses ROS with various software stacks and low-level programs that are piped, linux style. There were some pretty spectacular things here to look into further, and I've barely started going through the information in these links. I was impressed by the ability to identify and manipulate unseen objects the most. Speaking of which, it looks like they have a downloadable STAIR Vision Library that works with OpenCV, which I've also been meaning to try out (I suspect that once I'm past my current run of events, I will focus on building a robot with some sort of computer vision).

There's a very good chance that I will be building a simple robot to monitor the "lab" at work. Since we're not moving the office to a new location before the summer, we've started renting out a second office in the same building for our lab. The lab gets very hot - we're running large amounts of computers and networking gear in there. Having it in a second office means that it can use a separate air conditioning system instead of overworking the AC system that we need to keep people like myself from overheating (as it is, we have fans set up outside of cubicles in a few places). When I heard that we had a need for something that could remotely tell us the temperature over the internet, the part of my brain that remembers "crazy things people have used Arduino and Twitter for" leaped into action.

First, I found out that homebrew RCX temperature sensors are easy enough for someone with my level of electronics skill to build. Then I realized I could get away with tethering a simple RCX-based 'bot to a random Linux PC (need to check on serial ports yet, but I don't expect much of an issue there), and set to figuring out if I needed additional drivers to run an old serial port IR tower on Linux. It turns out that running the LEGO hardware on Linux is easy, complete child's play, and that there's even a perl module for it. If that's too easy, there's also a command-line interface for NQC that I had completely forgotten about. The remaining issue now is just buying the resistors necessary to build the homebrew sensor (the one described here can't be found easily online, but I will try a RadioShack tomorrow)- the rest of this can be done at work. Of course, once you have an RCX on the loose already, it's not hard to imagine us finding ways to expand on the idea...

Recent Photos

I've recently uploaded several bunches of photos on flickr. I decided to give up and go pro. That gives me two years before I need to come up with a better photo solution (although notes and the social aspects of flickr do appeal to me, the thought of needing to pay Flickr/Yahoo! ~$2 a month until the end of time does not).

I'm particularly interested in feedback on the instructions for the pneumatic walker. A finalized version of those will appear soon, and I'd like to see that version be more user friendly in addition to the model itself being more functional.

Here are the new photo sets:

• Robot Rumble 2010
• Primitive Walker Concept
• Walker I instructions (this is the one I want feedback on)
• LEGO Technique Studies (I'll probably add to this one occasionally without posting about it here)
• Joe Meno's February/March 2010 WITC
• BrickFair 2009 (previously posted to Brickapolis' flickr account - but I wanted them on mine now that I've gone pro as well)
• LEGOPalooza 2010
• Over the Rhine March 13th 2010 (proof I need concert photo tips)

Behind the Scenes Work

Not too much is happening here - last week's show was a bit of a bust for me but went surprisingly well overall in spite of some drama within NCLUG (in spite of months of work, the project I wanted to display at this event was not yet presentable). While I'm not used to having a supporting role at a LEGO show, things seem to have gone off well. The extra time came in handy - I ended up having some "work work" to do over the weekend, and I managed to squeeze in a concert on Saturday night. I've barely started attempting to clean up or post photos yet. I am now prepping for Robot Rumble this upcoming weekend. The next few weeks will involve more tidying up (my build area is currently absolutely unsafe) and preparing various things I'm planning on bringing to Maker Faire.

It looks like I'll be on my own for Maker Faire this year. Speaking of NCLUG drama...everyone wants to do more shows, but when we have one that's ours for the taking, nobody else wants to participate. There are some issues involved with coordinating a large group for a one day show, but I'd definitely say it's worth it to engage the larger hobbyist/DIY community and not just the families that tend to go to LEGO-only shows. Their loss - I'll be there and we'll have a great time. My only concern is that I might not have enough time to see the various other exhibits at the Faire.

Speaking of not having time, I'm stalling my wheels on pretty much all of my projects lately. In the interest of making it look like there is some progress on the fix-the-blog front, I've played around with the new Blogger Template Designer for a few minutes today (personally, I'm not happy with this tool but it's a slight improvement on their previous WYSIWYG GUI). I'm still not happy with the layout here, but I think it's a step in the right direction. I'm still interested in wasting much less space on the sides of the screen - and I'll probably switch to a 3-column set-up with a proper profile and contact info at some point - but this will have to do until I have more time available.

With any luck, my little pneumatic walker built entirely from the current LEGO Pneumatic Log Loader set will be working well enough for me to work out instructions soon - the current goal is to have that project finished and on display by Saturday. It seems like I can get simple walking mechanisms working, and I can get the binary adder control circuit working (don't worry, I'll explain this when I post instructions), but I can't seem to get everything working well together. As of this writing, the legs slip to the side more than they actually walk forward.

Google AI Challenge

I know that I shouldn't have started this with all of the other things I have on my plate, but it's fun and not too difficult to get started on. The Google AI Challenge contest going on now (February 4th 2010 - February 26, 2010) is a simple contest to create the best AI that plays Tron. It's a fun, lightweight little bit of ASCII-art action that you can watch right at the command line. No word on prizes for winners yet. Full details at the link above.

You could probably beat the relatively simple approach I've used so far (after I finished my first two real entries, I realized both had been suggested on the strategy page). It's pretty exciting watching scores jump - each entry is graded and ranked against the other entries (the server hosting the challenge is set up to automatically play the bots against each other).

A Clever "Page Not Found" Message

Saw this this morning and thought it was clever. Definitely a classy way to deal with an issue that drives people away from a site (personally, I went back once I realized it wasn't a more generic 404 message).

Speaking of websites - how long has the sidebar on LMOTD been pushed past the side of the page? It looks pretty awful right now and I'm worried about what caused it. I have, once before, been disappointed to see a Blogger code issue mess with my HTML on the site, but I've never seen them break a layout in this manner before. I'm also a little suspicious of my less code-savvy co-blogger, who had added a few features on the sidebar (some of which I'm removing now for the sake of keeping the site looking clean, others I intend to keep - sidenote, I've now gone back to only allowing LMOTD co-bloggers to have author privileges and not admin privileges. You can't be too careful). I'm hoping to fix the bug tonight. EDIT 7:19 PM EST: Turns out that this bug does not cause anything unusual in Firefox. Users of Chrome, IE8, and Opera aren't seeing it correctly. RSS feed is unaffected.
Nevermind about the apparent LMOTD issue, turns out that it was caused by a large graphic that caused issues on some sizes of monitor. I'm generally pretty good at leaving things open so that they can wrap wherever they will (CSS obsessions and Google's Browser Size need not apply), but a graphic left with dimensions larger than a 15" monitor will always be a graphic larger than a 15" monitor. It's fixed now and I guess I'll have to be more careful next time (that post was one of several recently that was clearly a bit rushed). The surprising thing is that no angry comments or e-mails came in about this one - usually if I do something wrong, I get called on it pretty quickly. I like to joke that that's how I know I'm famous - you know people are reading if there's enough people out there that someone will jump on you within a few hours if you get something wrong.