The plastic hat debacle

Humans are an interesting bunch. Out of all the interesting living beings on this planet, we stand out like Keith Richards at an insurance sale. Of course there are many reasons for this and one of my favorite ones is the invention of the helmet. Like Jerry Seinfeld said before: Why did humans invent the helmet? Well we were engaging in activities that were cracking our heads. But unlike any other sane living being, we chose not to avoid these activities. Oh no. We chose to make little plastic hats so we could continue our head-cracking lifestyles.

I am an avid motorcyclist and here in the Netherlands, you have no choice. Helmets are mandatory. Anyone you talk to here is basically 100% convinced that helmets are a good idea. But in America, the discussion is far more interesting. Pro-Helmet people and Contra-helmet people battle eachother fiercely, throwing back and forth seemingly solid statistical data. Anyone with even the smallest amount of knowledge about statistics knows that it's all about interpretation of the numbers. Given enough reasoning, you can prove an elephant can hang from a cliff with its tail tied to a daisy. So the statistical discussion is not that interesting to me. But if you take the statistics out of the equation, you are left with a rather simple discussion. The contra-helmet people will tell you that a helmet will restrict your view, muffle your ears from hearing the sounds of traffic and will snap your neck like a twig under the extreme G-forces that will occur during a crash. The pro-helmet people will tell you that it's better to have a sheet of plastic between you and the road when you slam into it. I have to be honest, I felt there is merit to both agruments.

As the picture at the top of this blog will testify, I am guilty of riding without a helmet as well. This particular picture was taken on one of the busiest highways snaking though Miami. Up to now, I have clocked about 3000 kilometers riding Harley Davidsons in America and about three times that riding a Kawasaki in Europe. Remember that statement about the "unrestricted view"? Well if you go over 50 km per hour, you need to wear goggles. If you don't, the wind will basically blind you. Try looking straight into a hairdryer and you will get an inkling of what I mean. These goggles restrict your view just as much as a helmet does! Second, sound! Believe me, with wind blowing past your ears, you won't here much more than: WHOOOOOSH. As for the neck-snapping, i can't testify to that as I have never crashed. But a head weighs about 5 kilograms, a helmet weighs about 1 kilogram. I'm not sure the 20% weight increase will suddenly make a dramatic difference.

So, no reason to not wear a helmet? Well, there's a catch. There is simply no substitute for feeling the wind in your hair as you ride along the highway at 140 km per hour. The feeling of freedom is simply astounding. And there you have it! Here the pro and con camps are battling eachother on the basis of fact and statistics. And all the while, the real crux is an irrational one. It's the same reason why people jump from planes with an oversized unbrella strapped to their backs. Sometimes you just want to something that makes you feel free. I know, it makes no sense. But be honest! you feel it to..... don't you!

Jeroen Breukels

Blimps and kites

Kites have literally been known for thousands of years. Blimps, or Zeppelins, were thought to be THE means of mass passenger transport in the 1920's and 1930's. One could say that both are an old idea and both were very highly regarded in the past. Kites often had religious significance in Asia. They also had a large contribution to our understanding of the dynamics of modern aircraft configurations. A feit most often overlooked these days (I thought i'd mention it seeing that today it is exactly 111 years ago that Otto Lilienthal crashed and died). Blimps fell out of grace after the horrible incident with the Hindenburg 70 years ago. And even though the concept didnt completely dissapear, none of the modern instances managed to attain the same level of grandeur.

So, two old ideas.. and no one ever put them together! you see, that is what I love about science and engineering. You can be standing in the shower and suddenly think up something that has never been done before!

Lately I have been involved in designing a launch system for the Laddermill using a 25-foot helium blimp. It suddenly seemed so obvious. Much of the time, the winds close to the ground are too erratic to launch a kite. But once you manage to get it above 50-100 meters, it'll fly just fine. Getting a kite up to 50 meters in low wind conditions is like trying to get smoke into a coke bottle with a baseball bat! You know the smoke fits in the bottle, you just can't manage to get it in there. Running, pulling on the tethers, giving it slack, running again... this kind of proces is exhausting, and may very well yield no results whatsoever.

In comes the blimp, with its 23 cubic meters of helium, it has a nett. buoyancy of 11kg. We stand and watch how it effortlessly transcends the first 50 meters of altitude. With no fuss it pierces what was for us an impenetrable wall. Fantastic! we can use it to piggy-back a kite to an altitude where there is sufficient clean wind. The kite is a Peter Lynn Venom, a kite in the shape of half a circle. This shape fits nicely over the top of the blimp like a saddle on a horse. All it needs now is to be fixed during ascend and to be released on command. Making use of a few hardpoints on the blimp, carefully taking into account the introduction of potentially large forces into the fragile blimp material (Oh that 1st year mechanics course sure is paying off now :) ), the kite is strapped to its back.

At first, i had expected it all to look a bit comical. But actually, it looks very natural. Like the whole thing is saying to us: why didn't you think of us before? And thus, an old idea solves a new problem. And this is why you should never throw out your old notes. Never discard those old back-of enveloppe sketches. You never know what can bail you out!

Jeroen Breukels.

Start of a habit

It is not often that one conciously recognizes the start of a habit. This would be one for me. funny thing, it's not that special at all. I guess that is why usually people dont notice the start of a habit. it's just not worth the attention. It's the end of a habit which seems to be the more interesting bit. from my current mood I can deduct that the beginning is pretty much in line with everything else that is going on. basically the same local derivative. At the end though, the orthogonality of the habit with respect to the rest of your life is what tends to get you. No wonder people pay the most attention to the end....

... and that marks the end of the beginning... All that is left is the middle part.... and the end ;)

Jeroen Breukels.