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Posts from March 2010

An Amazing Display of Intelligence

Tuesday 30th March 2010

Actually two displays of intelligence, but both of them are linked to each other and both lead to a single result.

One of my lecturers at university likes telling us to “think from first principles”. That is, to look at a problem and to work out what is really causing the issue, and therefore come up with an engineering solution which solves that. An example he used was the bridge at Boscastle. In the aftermath of the 2004 flood, a problem was that cars got washed into the river and crashed into the bridge, which ended up blocking the flow of the river thus causing more flooding. A bunch of people looked at this and decided that the solution was to build a new bridge with a larger gap underneath so cars won’t get stuck there.

My lecturer’s suggestion was to put fencing of some sort along the sides of the river, to stop the cars going into the water in the first place. You don’t need much of an engineering background to realise that this is cheaper than building a new bridge! A much better solution.

One of the things I love about F1 is that the engineering is absolutely brilliant. And McLaren are one of the best teams in F1, so their engineers are pretty damn good. And they came up with something on their new car which I find amazingly impressive.

F1 cars run wings to create downforce. Downforce pushes the cars onto the track, which means they generate more grip and so can go quicker in corners. This also induces drag though, but in corners this isn’t as much of an issue because the extra grip makes up for the extra drag. On straights though, grip is less important than the drag of the car so the downforce is sort of “wasted”. The cars are therefore set up as a compromise, to give the best amount of grip in the corners without lowering the top speed of the car too much on straights.

But something F1 designers have looked at for years is trying to stall the wings on straights. This means stop them making downforce when it isnt needed, so there is less unnecessary drag. One way to do this is to have manually operated wings where you can change the angle of attack (like on aircraft). This is banned, for safety reasons. Another way is to have the wings deform under a certain load, so they bend into a shape which produces less downforce. Again, it’s been banned for safety reasons. But McLaren have come up with a new way to stall the rear wing, and it’s brilliant.

They have a vent in the front of the car, which carries air in a duct along the length of the car and onto the rear wing. This flow of air is positioned in a way that upsets the air flowing over the wing and so stalls it, so that the wing stops producing downforce and so produces less drag. Now, if you do this you need a way to turn it on and off, so that the vent only blows onto the rear wing on the straights. Otherwise the car will lose downforce in the corners and won’t go as quickly. They aren’t allowed to use some sort of mechanical system becuase it would count as a moveable aerodynamic device, which is banned. The solution they’ve ued is ridiculously simple. The duct runs through the cockpit, and has a hole in it. This means that when the hole is uncovered the air simply vents into the cockpit, keeps the driver a bit cooler and doesn’t upset the flow around the rear wing. When the driver covers the hole up though, the air flows to the back of the car and stalls the wing.

This is a stupidly simple solution, and completely beyond the scope of the rules. The thing which moves is the driver’s leg, and you can hardly ban drivers legs from F1! It’s a wonderful bit of engineering.

The second display of intelligence concerns one of McLaren’s drivers, Jenson Button. He won the race on Sunday with a decision to change tyres before anyone else, and with some brilliant driving. Everyone started on wet tyres because it rained at the start, but after a few laps it stopped raining and a dry line started to appear. Button realised this before anyone else and then changed to dry tyres, which moved him up from about 6th to 2nd place. He then kept those tyres till the end of the race, but not just that he managed to do consistently quick laps. The other people who were on the same tyres for that amount of time just couldn’t keep up with him.

On the other hand Button’s teammate, Lewis Hamilton, seemed to completely lose his head during the race. He really lost his composure, which quite surprised me. Before this season, most people sort of wrote Button off because the consensus is that Hamilton is quicker. And he probably is. But the thing is that the difference is probably only a few tenths of a second, and Button is possibly overall a more intelligent driver. Like in the race on Sunday; he knew when to change tyres. He knew not to push too hard on them, which meant that even at the end of the race – when drivers like Hamilton and Webber were on much newer tyres – his tyres werent too worn to stop him going quickly enough to win. I was watching the race with live timing, and his laptimes were amazingly consistent all the way through. Honestly, his drive on Sunday was one of the best I’ve seen – from anyone – for ages.

Motorsport at this level is not just about outright pace. Clever strategy can count for a lot, and it means that the battle between the McLaren drivers this year is gonna be a fascinating one.

If you havent already, watch the race on iPlayer. Well worth it because it was awesomely entertaining.

Posted In: EngineeringMotorsportTechnology Tagged: | 2 Comments

Moon

Thursday 11th March 2010

I saw Moon last night, and I can’t really decide what I think about it. Before I go further there are some spoilers here, so don’t read if you don’t want them.

Don’t get me wrong, I enjoyed the film but bits felt iffy and I can’t completely put my finger on why. I think it might be down to some of the most glaring factual errors you could think of. For instance, Moon gravity is a sixth of Earth gravity, folks! For some reason, whenever the characters were outside the base they moved much slower, as you’d expect them to in low gravity. But inside they moved normally. Hell there was a game of table tennis at one point, which struck me as particularly implausible. And also, they’ve somehow found a way to increase the speed of light, given the instantaneous communication between the Earth and the Moon.

It probably sounds like I’m nitpicking, but I don’t think I am. For a film called “Moon”, you would expect the film makers to have grappled with some of the fundamental physics of the place, and at least have come up with a reason why they choose to ignore them.

Regardless of that, it’s still a pretty enjoyable film and I really like that it’s a proper, pukka, science fiction film. Far too often sci fi just means “set in space”, as opposed to what sci-fi actually means; stories based around some sort of scientific “what if?” – for instance, Star Wars isn’t really sci fi, its just set in space. Of course, it’s another thing completely to say how good a SF film Moon is. Given that it ignores fundamentals like gravity, you could argue possibly not…

Anyway, I enjoyed it. But then I should, because it steals elements from quite a lot of other Science Fiction. It takes bits from 2001 (sentient uber-computer – Kevin Spacey plays the part, and you can tell that his brief was “sound like HAL!”), Do Androids Dream of Electric Sheep? (implanting fake memories), The Moon Is A Harsh Mistress (using a catapult to sneak people to Earth, amongst other things), a sort-of allusion to Asimov and the Laws of Robotics. I’m sure I’ve read a short story by Clarke too about clones which the film echoes quite a lot, but I can’t be bothered to look through the books to find one.

It sounds like I’m being negative, but I did enjoy it and it’s well worth watching. Frankly it’s a much better film than most of the trite that gets released (mentioning no Avatars). The story may not be groundbreaking but it’s watchable, and other things more than make up for it. It’s rather nicely shot, especially the scenes which are set outside. And I also think Sam Rockwell is pretty good too as the main character(s). Kevin Spacey is ok as the computer, but it felt like he was trying to be HAL and failing – he didn’t quite get the pure emotionless tone that Douglas Rain managed in 2001. And by the way if anyone hasn’t seen 2001, you really should because (except for the first bit with the apes) it’s stunning. But then Kubrick was a great director and Clarke a great writer, so it’d be odd if it weren’t.

I think though that the best thing about the film is the soundtrack. It suits the film really well, helps the pacing and overal “feel” of the film, but it’s also just really good music. At the end I actually left the end credits run, because I was enjoying the music that was playing. It’s on Spotify so I suggest you all go listen now.

An interesting point came out of watching this. The other day I was having a discussion with a housemate about how you’d build on the moon, and specifically we were talking about concrete. We couldn’t decide whether the curing reaction needs air to work (I’m not sure it does, looking at it now), but irrespective of that you’d need to ship materials up there, which takes a lot of energy. When I was reading about this film though I ran into an article on Lunarcrete, which uses stuff found on the Moon to make a concrete-like material. I think they’ve even suggested using lunar glass as reinforcement (glass has a ludicrously high tensile strength. Concrete has very little, so thats why reinforcement is used), which is pretty cool. Apparently Lunarcrete isn’t airtight though, which is a fairly glaring flaw. And It also requires a lot of energy to produce, which is another issue. I presume the energy cost is still lower though than transporting a similar amount of concrete to the Moon.

Personally I think I’d just build underground, but then that probably also requires a lot of energy.

Posted In: Engineering Tagged: | 5 Comments

Get Oval It

Wednesday 10th March 2010

Ignoring any question of how entertaining it may or may not be (500 mile races where only the last 2 laps really count? Why not just race for 2 laps them?), oval racing is incredibly dangerous. There’s no way it can’t be. The corners are banked so the cars can go quicker, which means that all the way round the outside of the track is a wall. At most road circuits like the ones raced on in F1 or touring cars – which are more interesting and provide for more compelling racing – there is runoff. The walls aren’t right next to the road the cars race on because that’d be rather dangerous.

So in NASCAR, what we have are cars lapping very close to each other, at about 185mph, with a wall running all the way round the outside of the track. When things go wrong it can be nasty, because if you fuck up there’s a very good chance you’ll be going into said wall at 185mph. Which, all things considered, is less than ideal.

In the last NASCAR race, one of the drivers – Carl Edwards – committed possibly the worst foul I’ve ever seen in any form of motorsport. Actually, probably in any form of sport generally- when someone fouls in football or rugby, it doesn’t send them crashing into a wall and flip them over. At 180mph. This was insanely dangerous, so what would you expect the driver’s punishment to be? A ban for a few races? Maybe even a permanent ban? Massive fine? Guess again! He’s been put “on probation” for 3 races. So he’s ok as long as he doesn’t deliberately crash into someone in the next 3 races.

F1 got this right last year. In the wake of the Singapore 2008 scandal, the FIA effectively purged everyone who was involved from the sport (except for the drivers, but Piquet essentially purged himself by being shit, and Alonso “didn’t know about it”. Sure he didn’t…), which sent the message that “this is not acceptable”. Edwards’ misdemeanour in Atlanta was much, much worse, so to my mind the fact that they’ve not really punished him only serves to discredit NASCAR.

Not that there was much to credit to start with, but that’s a different debate…

Posted In: MotorsportRant Tagged: | 2 Comments