It does, you know. You just have to get it hot enough.

Tuesday, July 29, 2008

xref: Physical Computing’s Greatest Hits (and misses)

Been busy, but time for a quick xref: Tom Igoe has a really nice write-up of common projects in physical computing classes. More importantly, he explains why all these (often) obvious projects are still worth doing in class and why students shouldn’t feel like they’re just duplicating someone else’s efforts.

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posted by jet at 11:05  

Saturday, July 19, 2008

Review: Vehicles, Experiments in Synthetic Psychology

A few days ago I finished Valentino Braitenberg‘s Vehicles, Experiments in Synthetic Psychology and I have been letting it gel while trying to figure out how to write about it. Vehicles is a short book written in plain English without a lot of fancy technical talk and yet I feel like someone’s taken my brain and run it through a thing that makes brains different. Braitenberg leads the reader through a series of thought experiments creating vehicles using only sensors, connectors, motors, and a few other basic items. Starting with simple vehicles that can drive around a table top, each short chapter adds a concept or idea to make the vehicles more complex and capable of more sophisticated actions. It’s not long before the imaginary vehicles have the complexity and capability of humans and I found myself going back to re-read chapters thinking I’d missed something. Even before I finished, I was already looking at my cat differently: ‘Is she experiencing a correlation match or causality match with past events? Does she have any comprehension that my head and my hands are connected and related or are they all just correlations?”

This morning I was watching video of some flocking behavior and it it hit me that this is a perfect example of what Braitenberg is talking about in Vehicles when he describes “the law of uphill analysis and downhill invention”. A key reason for using thought experiments is that as outside observers, we are often unable to comprehend why something exhibits a specific behavior and are unable to build or define a structure that would exhibit a specific behavior. On the other hand, we are able to build simple things and understand their behavior because they are things we have created. His suggestion is that rather than spend lots of time and energy trying to analyze behavior from a top-down perspective, try building things from the bottom up and see if we can replicate the sort of behavior we’re trying to understand.

As a software type interested in kinetics and robotics, “top-down vs. bottom-up” is a very familiar argument. Every time I work on a distributed computing problem in CS, I (and my cohort) default to a top-down, control-the-flock algorithm that makes each element of the group do its thing. When I got into MIMD programming on supercomputers, I would solve problems by having different nodes exchange data needed to make decisions, but it was still “Thing A decides what to do after taking orders from or talking to thing B”.

I’m pretty certain birds aren’t having little chats about where they are headed next, and they’re probably not psychic, nor do they otherwise communicate with one another across space and time. My assumption (not being a biologist or psychiatrist) has always been that the “separation, alignment and cohesion” argument explains things; as a software type, it’s something I find easy to implement. How birds can see/think/react so quickly to small objects at a distance is beyond me, but again, I’m not a biologist.

Looking at things from Braitenberg’s perspective, what if it’s a much simpler solution? Perhaps the birds aren’t going through an observe/calculate/act cycle and are instead merely responding to the cues of their neighbors using learned behavior memorized (or evolved) during their lifetime. Pattern A results in Action A, Pattern B results in Action B, etc. If there’s an error — hey, that’s not pattern A — then a quick decision is made to either continue with Action A, go back to the previous action, or react in a new way to try and solve the problem.

I don’t know if that’s the right answer, but I’m starting to think about making some Arduino-based flocking robots for a little tabletop exercise. Even as a thought exercise that I never get around to building, it’s an interesting question. Can individual bots learn to flock based on keeping distance from things next to them and learning a set of patterns to repeat based on the movement of their direct neighbors?

If the flocking of birds, the action of ants and bees in colonies can be explained or modeled using this bottom up behavior (I suspect it can), how would we humans benefit by implementing similar, bottom-up mechanisms?

For example, why does Amazon need to collect all sorts of data about me (in an identifiable, non-anonymous database) just so I can get “other people who like what you like” style suggestions? Why do we need a centralized server to track all our listening histories — why not share it with people physically near me as I wander around town or post updates to my “Universal Friends List”?

On a more abstract level, instead of Master Control Programs sucking in data and spewing it back out, why can’t our MP3 players and book viewers and phones and laptops exchange information with nearby peers, constantly updating and exchanging anonymous lists of data, analyzing it, and reporting back to us?

Using the insect world as a parallel, what if all of our electronic devices behaved more like bees in a colony, each doing simple things with nearby (physically or electronically) devices leading towards a greater benefit for all? Do we really need our technology to be set up in a virtual army, taking orders from other systems in a hierarchy run by governments and international corporations?

Vehicles is an easy book to read and a hard book to describe. It really is one of those, “trust me, read it” books that you force on your friends until they read it just to get you to shut the hell up. Which, to me, is one of the best things you can say about a book.

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posted by jet at 10:55  

Tuesday, July 15, 2008

Spimewatch: Mass Sensor Networks

The amateur radio crowd have been doing interesting things with the Internet and its precursors for awhile now. One of my favorite examples is the proliferation of online receivers, radios that have their audio out and controls connected to a web site. You can transmit on your radio, tune into their radio, and see if your signal makes it to some remote location. The downside is that receivers can only tune to one frequency at a time, so you have to take your turn if the receiver is in an interesting location. Also, they’re typically not very portable, requiring large antenna installations and reliable Internet connections, but they’re still a remote sensor you can use to collect information.

This morning I discovered Pachube, a “service that enables people to tag and share real time environmental data from objects, devices and spaces around the world. The key aim is to facilitate interaction between remote environments, both physical and virtual.”

In the space of a few moments I looked at the river conditions in Bastrop, TX; humidity and “leaf wetness” in southern California; and data from various sensors in a home in Japan.

Ok, so poking around on a website is fun and all, but Pachube also will feed this data out. All I need to do to have my automated lights turn on and off in sync with those in the Japanese living room is pull a data feed from Pachube then use something like Arduino to drive the hardware.

What will be really interesting is when there are enough tag readers attached to something like this to track arbitrary objects through the network. Online package tracking will seem quaint by comparison.

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posted by jet at 13:42  

Saturday, July 12, 2008

The Future of DIY

If you’ve ever played Team Fortress or TF2 or Half-Life or probably any major FPS, you’re familiar with autonomous gun turrets.

Some guy built one:

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posted by jet at 21:48  

Wednesday, July 2, 2008

How much oil did you destroy today?

Yesterday I threw away three ballpoint pens in a row. Normally I write with a fountain pen, but my workshop is grimy thanks to all the machine tools and no place for a schmancy fountain pen. I finally found a pen that worked, drew what I needed to draw and made some notes then went back into the house to throw away the empty pens.

I didn’t actually “throw away” three pens as much as “dispose” of them or, in essence, “destroy” them. They’re not recyclable that I’m aware of and not refillable, either. So there’s 1.5 oz (yes, I weighed them) of plastic and a tiny bit of metal that I destroyed by sending to a landfill.

How much oil did I just destroy? Probably not that much. But those pens came in boxes, factories needed to make the ink used to color the plastic, all of that had to be delivered somewhere. Still, probably not that much oil for three pens.

On the other hand, how many pens have I destroyed in my life? I remember buying disposable ballpoints by the box in college, so I’m guessing a lot of pens, so maybe, what, a gallon of oil? A barrel of oil? I’m not going to go all Jamais Cascio and calculate the amount of oil I’ve destroyed in the form of ballpoint pens, but I’m going to hazard a guess it’s a non-trivial amount, especially if you include the fully-loaded cost of the designing, making, and distributing of the pens.

Side note: Years ago I switched to mechanical pencils just because I like the feel more. I still have some of the same mechanical pencils I bought seven or eight years ago — including my favorite, Ohto Pro-Mecha architecture pencils. I have worn out four of the Ohotos (all .3, I guess I have a heavy hand?) and need to fix/replace/recycle them. Of note, they’re made almost entirely of aluminum with only a small amount of plastic. If I can’t fix them, I can always toss the metal bit in the recycling bin with all the other metal scrap that I take to the dealer once or twice a year.

So, I threw away — destroyed — three pens yesterday. How many have I destroyed in my life? How many have you destroyed? How many have we collectively destroyed? How much oil have we collectively destroyed in the form of disposable pens?

BIC says they sell “24 million BIC(tm) stationery products every day” (emph. mine). They also say, “BIC(tm) products are the choice for any consumer who wants to protect the environment.”

Say what? If I want to protect the environment, why would I buy disposable pens and disposable lighters and disposable razors, all made using oil and intended to be destroyed instead of recycled or reused? I’m going to go out on a limb here and suggest that maybe it’s actually bad for the environment (and a waste of money) to buy things knowing you’re just going to destroy them.

Ok, so how do I go about not destroying any more oil in the form of disposable pens? Let’s try the “reduce, re-use, recycle” solution.

Reduce: It’s difficult to reduce the amount of drawing and writing I need to do, but can I reduce the amount of pens I use? Is there an alternative to disposable pens? I like Prismacolor pencils, and they’re good for some of my drawing, and when I toss the shavings and the stub into the trash they’ll go to a landfill where maybe they’ll decompose. They are a bit of a pain to use on a plane or in a car as they have to be sharpened often and they’re also fragile — dropping them will break the core and make them useless. They also don’t work well with some paper and they aren’t as permanent as ink. Face it, I’m still going to need to use ink pens of some sort.

Reuse: Another option is to stop throwing away — destroying — the entire pen. Copic makes a number of pens that use refillable inserts and replaceable nibs. True, those go in the landfill once they’re empty/worn, but the body of the pen is metal and will last quite some time before getting tossed into the recycling bin. I’m still using one I bought several years ago, and I’ve replaced the ink and nib a few times now. (Copic also makes a wide variety of refillable/repairable markers along with disposable pens and markers.) When I was a kid, replacing the insert was pretty standard and I still have a couple of U.S.Gov. black ball-point pens that would work fine today had I a refill handy.

For note-taking in class and general writing, I’ve switched over completely to fountain pens that can be refilled from a bottle of ink. Yes, they can be a bit messy some times, but I’ve bought a few 3oz jars of Noodler’s water-resistant ink, enough to last me a kerjillion years. I suspect the nib on my pen will also last me most of the rest of my life as long as I don’t drop it on concrete or somesuch. If I didn’t like refilling I could buy ink cartridges, but again, I’m destroying oil when the cartridges are empty.

Recycle: Not an option with any of the disposable pens I’ve seen. If someone is making pens that I can put in with the #1 and #2 plastic (all my city takes), please let me know. I’m pretty certain none of the pens I destroyed yesterday were made of HDPE.

So, there’s my solution: fountain pens for most of my writing, Copic markers and Prismas for drawing. I suspect I can go the rest of my life without destroying nearly as much oil as I used to in the form of disposable pens.

Am I saying that people who use disposable pens are evil? No, and I’ll continue to use Sharpie Industrial disposable markers when I need to make semi-permanent marks in the shop. (However, I should buy them in bulk instead of in the three pack that uses paper and plastic packaging.)

What I am saying is that we destroy a lot of oil in the form of disposable pens, and that there are steps we can take to reduce the amount we’re destroying. Each of our solutions will be different, but collectively we can prevent a lot of oil from being destroyed.

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posted by jet at 12:24  

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