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Archive for the ‘industry’ Category

Apple’s Iphone, the various Google Android phones by Samsung, HTC and probably others, and Nokia’s Symbian phones are fighting on the smart phone market. As far as I know, Iphone is “closed” and you can only download those apps that Apple lets you have. Android lets you use any apps, and I assume Symbian is similar, though I’ve heard it’s old-fashioned. I don’t have real experience with any of these phones.

What’s really missing from the palette is an open source OS.

Well, there is one, Nokia’s Maemo, nowadays called MeeGo when they started co-operation with Intel. Only one phone, N900 uses it currently. I’m waiting for the next one, N9. Just look at a source example. All graphical development is done with Qt. It’s apparently not sucky since even XFLR5 managed to move into it quickly.

I’m using Linux at home, Windows at work and a Mac every now and then, like when the Windows is acting up every day or when I’m not at home. So this writing comes from a Macbook.

I hate Windows’ instability and sucky performance, Apple’s quirks and desire to do things differently (how do I get {} brackets on this keyboard?) and Linux’ need to fiddle with configs to get things to work.

I love Windows’ hardware versatility and choice of programs, Apple’s “things just work”* approach to software and hardware and Linux’s powerfulness and openness.

As a phone, I’m using a Nokia 6310i from 2002. The battery lasts more than a week and the user interface is snappy. It has a monochrome display. Hope N9 will be ready soon. You could run Dosbox on N900. Irssi. XFLR5. Just anything. In case something goes wrong, Android will be my fallback option.

*who ever thought that waking from sleep mode should take 15 to 45 minutes,
or connecting to a wireless connection should take forever and require ten
different cross-preventing logic levels? That every week you should
download updates that would require long installing times and reboots?
That the additional desktop room should switch from the left to the right side...
Apparently, someone at Microsoft, but nobody at Apple. I don't think it's
great innovation, it's just making things not suck.

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Inspired by Michel Van (not Scott Lowther as mentioned earlier) at Secret Projects, who ran into the Gemini inflatable Rogallo wing test videos that are now available (not embeddable so linked only). There are parafoil systems for airdropping stuff, though they don’t seem to be doing flares or line pulls to soften the impact:

And if somebody says parafoils are not maneuverable, I give you a Russian self built RC parafoil:

Speaking of rocketry, a member from the local hybrid group said they have found out the probable cause of roll control problems: the forward fins that were put on the rocket for roll control cause huge vortices when deflected, so that they effect the main fins far aft and the effect might be the opposite from intended.

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Or The Space Game, by ESA.

The Space Game Screenshot

Minimize delta vee by moving the planets around (this changes the probe's arrival time at the planet). This shows my best solution so far, with some playing one evening, about 13 km/s

This is a nice javascript webpage where a probe is shot from Earth to Jupiter with gravity assists at Venus (twice), Earth and Mars. You try to achieve the lowest propulsive delta vee. You decide when the spacecraft arrives at each encounter and the program basically calculates the rest. It’s quite a nifty little piece of Javascript, the future of web applications is like this. It works fine with Chrome on Linux at least. Probably IE will have problems but who uses that anyway?

I’m ranked at #39 at 12.74 km/s… Far behind the gurus who get below 10 km/s readings! There are apparently some prizes for the top three, but I think people are in it for the fun of it.

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Most people with interest in aerospace history know of Barnes Wallis’ geodetic structures, most famously used on the Vickers Wellington. He first invented them for the R100 airship, basically a weave of thin aluminum shapes going in different directions, forming a grid. No bulkheads or even wing spars needed, but it was quite complicated to build. Fabric was used as a cover, first linen and later thin steel wire mesh. It became outdated when airplanes were pressurized and moved to aluminium monocoque structures.

Vickers Wellington with some skin shot off

Well, now, airplane manufacturing technologies are changing again, after some 70 years of riveted aluminium sheets, bulkheads and spars. Composites laid by robots enable fancy shapes, and optimizing the strenght carefully in various directions. Boeing has been looking at a 737 replacement. So far, pressure hulls have had to be cylinder or ball sections – only that way the thin skin can be in pure tension, the only force it can really resist. Often a double bubble has been used, with the cabin floor dividing the lower and upper half into two circular sections and also keeping the left and right side together at the same time. A circular frame is not very space efficient for humans though, so Sankrithi et al at Boeing figured out how to put fibers in a grid to enable a roughly elliptical shape that is wider than it is tall. The advantages are not entirely clear to me from their description, since they seem to say the ratio of seats per circumference is similar to a circular frame, but it is nevertheless interesting. (Also, it’s strange that Free patents online shows that the patent was filed in 2009, yet Google shows it was filed in 2005, yet they seem the same at first glance).

Fiber reinforcement grid geometries for an airplane fuselage

This has some relation to the X-33 where they also attempted non-cylindrical composite pressure vessels. The technology has advanced since though.

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In a patent by the famous Barnaby Wainfan. EDIT: corrected the link. This patent was filed in 2006 and granted in 2008.

Enter, turn, boost, glide

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From NASA Langley – they did wind tunnel tests on a model. Lots more pictures of various aerospace projects there too, some of them are quite weird. Thanks to Secret Projects forum for the info!

Rockwell X-33 wind tunnell model front view

Rockwell X-33 wind tunnell model side view

Naturally since Rockwell built the orbiter, this one looks like the orbiter too. With an SSME and RL-10:s (so Rand.org says) and cylindrical tanks, it would have been far lower risk than the Lockheed version that won.

In a sense, the “almost pure rocket” cone, the “flies a little better than a rock” lifting body and the “almost flies like a dangerous plane” winged vehicle are the three main paradigms to reusable vehicles.

Though, with SHARP (or like McD did with active cooling), your lifting body can be sharp edged and have vastly superior L/D compared to blunt ones.

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Huh, it always takes a long time to find anything on web pages that are so cluttered up. Here. No idea what the MPGe or miles per gallon equivalent is.

EDIT:

Here’s ERA’s video (they didn’t win, although they were very close. I think they were penalized for driving too fast):

Holy crap. Their vehicle has 1000 Nm torque and does 0 to 100 km/h in 6 seconds.

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