As Red as a Living Heart

On the dot of midnight, on the shortest night of the year

It's always night or we wouldn't need light

- Thelonius Monk

Of course this time of year up here it's always day, but it's not meant to be taken literally.

With Luke the Duke in Amsterdam

On my flight home from the Netherlands, for the first time in my life I felt "if this plane crashes and I die, human knowledge will be set back at least a few years". In retrospect, months might be more accurate than years, but still. Had I been a cartoon character, the light in question, in this case, would have come from a bulb above my head.

The meeting was a mixture of roboticists, bio-mechanicists, prostheticists, orthoticicists, and a few of us control theorists, all with a common interest in walking and balance. I got to try walking with a prosthetic leg (not so easy), I met Theo Jansen (see post below) and got to play with his kinetic sculptures and see how they are made.

Me playing with a kinetic sculpture

I also discovered that a big secret embarrassment for the walking biped robot community is that none of their robots can walk on rough ground. This inevitably raises the question: if they can only walk on flat ground, why not just use wheels? The best I've seen can handle a step down of about 8 cm, but that's more arse than class, and most will collapse if the floor varies by millimeters. The control problems are hard, and all current solutions are ad-hoc.

(turn your head 90 degrees to the right for optimal viewing)

The video above is of one of the better current robots. Note that the well-known robots by Honda, Sony, Toyota, etc have such big feet and take such small steps that they don't make any attempt to solve the problem of balance. We consider that cheating.

The thing is, I know how to solve the problem, how to systematically design stabilizing controllers for this type of system. We here in Umeå have just submitted a whole bunch of papers about it. At the meeting, after a few hasty napkin drawings and some stern words I managed to convince a few people of this, and got invited to spend some weeks at MIT in August doing some tutorial lectures for the robotics group, and testing out our ideas on some of their robots. I will possibly also visit Cornell.

I think it will be great fun, and as a bonus I'll get a chance to catch up with the following illustrious characters in Boston or New York: KC, KT+Mat, Marjukka, and David K.

Between now and then, I'll be back in Korea for a week, and then I'll have two weeks vacation in Slovenia and Croatia with Paul.

Kinetic Sculpture

Okay, ignore the fact that the video below is a BMW ad. This guy and his wind-powered "kinetic sculptures" are for real.



At the end of the month I'm going to a small meeting in the Netherlands about walking robots, and this guy builds his creations just around the corner from conference venue. Part of the program is to meet him and visit his workshop.

Pretty cool.

The Swedish Way

So I'm still breathing and eating, and enacting most of the biological consequences and prerequisites that those entail and require, respectively.

We recently had a bout of warm weather up here. Last week and the week before were all clear blue skies and scorching hot sun. Good timing really, because it coincided with a great Swedish national tradition: taking more days off than you are really entitled to.

1st of May is Valborg, an ancient pagan festival day welcoming the spring . In modern Sweden it has a triple function: Valborg, workers day (May Day), and Swedish national hangover day (unofficial). It's a public holiday.

The day before is Valborgsmässoafton (roughly: Valborg eve) on which a bonfires are lit to scare away the wolves and trolls so the animals can go back to the fields. In modern times, it has a double function: Valborgsmässoafton and Swedish national underage drinking day (unofficial). It is not a public holiday, but everyone takes it off anyway (or at least the afternoon), and it's traditional to start the day with a champagne breakfast, and take things from there.

This year, Valborg fell on a Thursday, which made Friday a "soft day". In Sweden, if there's one day between a public holiday and the weekend, it's "expected" that nobody turns up to work on the day in between. Readers with a talent for arithmetic will have noticed that from one public holiday the great Swedish system has somehow crafted a five-day weekend. That this coincided with a beautiful spell of warm weather meant one thing: Barbeques Galore! (Not the shop, just a lot of barbeques.)

By Saturday, everyone was a bit disoriented, having had two days in a row that felt like Sunday, and trying to deal with the fact that it was Saturday again. That day the mercury bubbled over to 24 degrees, which I have it on good authority was warmer than it was in Vienna or Croatia that day. Of course there was only one reasonable response to this: BBQ at the lake.

There was still a sheet of ice remaining in one perpetually shaded corner, but I suspect that it's gone by now. It was great to lie in the sun all day and cook up some burgers (I'm slowly convincing the swedes to include beetroot and pineapple).

So for a few days, everyone was back to t-shirts, shorts, bare feet. But I became complacent. Up here, even in warm weather, one should always carry a jumper with them. On Monday I was walking around town jumperless when a chill wind came down from the arctic without warning. Since then I've had a pretty bad cold, but have been so busy I haven't been able to take any days off. Booo hooo.

Next Friday I'm back on the conference wagon, heading to LA and then the Netherlands for two robotics conferences. Schedule will be extremely tight, but hopefully I can meet up with The Duke and Case in Amsterdam. In July I go to Korea again, then Paul is coming up to Europe, and we're probably gonna hit up Croatia and Slovenia, a week in each. Looking forward to that...

The Crazy House of Sofiehem

This is something I was going to write about a while ago, but for one reason or another I seem to have gotten sidetracked.

My best mate here, Texan refugee by the name of Cory, recently moved into a new share-house, known locally as the Crazy House of Sofiehem.

The front yard.

The story goes thusly: there is a man, who owns more than one house. This man is a little bit crazy. But he does not live at the crazy house. He lives in a house with his wife, and in that house his wife exercises absolute control over all decorations inside and out. It is a normal house.

The crazy house he rents out to students, including Cory. But anything on the outside or in the yard is his personal artwork and/or plaything. He can often be seen in the evenings scurrying around the backyard hanging new purple plastic christmas trees or some such.

The back yard.

This means that the house is constantly evolving, there's something new every time I visit. For example, one recent addition is this lovely Tyrannosaurus Rex coming out of an oven:

A new addition.

Apparently the crazy man used to come inside the house, and even walked in on a girl in the shower once. It was politely suggested that he respect his tenants privacy and restrict his creative activities to the exterior, and he has since complied. Inside, the house is actually very nice. Hardwood floors, nice furniture, original artworks on the wall (one of the tenants is a family friend of a famous Swedish painter).

Inside.

The house is quite well-known around umeå. One disadvantage of living there is the constant stream of people walking past taking photos, staring in the window as you eat your breakfast. On a recent skiing trip to the alps, I sent Cory a postcard addressed to "the crazy house in Sofiehem with all the lights, Umeå, Sweden" and what I later learned was the wrong postcode. It made it there just fine.

Cory out the front.

A couple of weeks after moving in, Cory spoke to the crazy man for the first time. The crazy man proudly showed Cory a birthday cake he had bought for his grandfather with a big 90 spelled in out candles.
Cory: Wow, 90, that's great! How is he? Is he still getting around alright?
Crazy Man: No, he's dead. He's been dead for 13 years.
Cory: Uhhh.... ok... so is this birthday cake thing something you do every year to remember him by?
Crazy Man: No, this is the first year I've done it.
Thence followed a long awkward silence, which in turn was followed by a brief farewell and good day to you sir.