Can I have Linux with that?

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.

Read Full Post »

Parawings and Rogallo wings, again

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.

Read Full Post »

Gravity Assist Competition

Or The Space Game, by ESA.

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.

Read Full Post »

Sankrithi Channels Wallis

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.

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).

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

Read Full Post »

The Turn-Boost-Glide-Back approach for first stages

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

Read Full Post »

Rockwell X-33 Pictures!

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!

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.

Read Full Post »

Automotive X-Prize Winners

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.

Read Full Post »

New Energy Production Processes – A Technical Lecture Series

There’s a free lecture series (it’s also a course but attendance is open) at HUT Aalto University about new energy technologies, organized by a friend of mine who works at the lab there. Here’s the lecture program (they will be held in the mechanical engineering building):

Thu 9.9. Introduction. Prof. Markku Lampinen: Energy conversion – From nanomachines to renewable sources.
Thu 16.9. CO2, greenhouse effect and climate change. Dr. Jouni Räisänen, University of Helsinki
Thu 23.9. Looking for a carbon storage, biochar as a win-win solution. Dominic Woolf, Swansea University, UK.
Thu 30.9. Biomass solutions for replacing coal: biochar, biomass gasification, multifuel power plants. Jukka Rouhiainen, Helsingin Energia.
Thu 7.10. Research on bioorganic fuel cells as power sources.
Professor Yohannes Kiros, KTH, Sweden.
Thu 14.10. Microturbines, a technology for local energy production. Professor Jari Backman, Lappeenranta Technical University.
Thu 21.10. Energy efficiency – “Negawatts” for cheap.
(Thu 28.10. middle term exams)
Thu 4.11. Wave power. Dr. Ana Brito e Melo, Wave energy centre, Portugal.
Thu 11.11. Geothermal energy, overview and the possibilities. Professor Eva Schill, Université de Neuchâtel, Switzerland.
Thu 18.11. Grätzel solar cells. Millennium prize winning breakthrough in solar energy.
Thu 25.11. Energy solutions for traffic – Which will win?
Thu 2.12. Student seminar
Thu 9.12. Student seminar (last lecture/seminar)

Reserve topics:
Wind power.
Passive heat technology/thermal engineering.
Solar thermal energy (STE).

Read Full Post »

The State of the Art of Washing Machines

..is despicable.

They take clearly too little water.
They take it clearly too slowly.

They idle far too much at the beginning.
They idle far too much at the end.

They do not offer fast forward capability like mechanical machines did.
They do not show their current status like mechanical machines did.
They’re often broken like mechanical machines were.

They make it unclear which programs have pre-wash and which don’t.
They make everything else pretty unclear too, like what a particular button does.

An ideal washing machine:
Large intake hose (or two if it is a model that takes warm water too where district heating or wood heating is available). When the user presses start, the machine starts taking water at full speed at that precise microsecond, unless it is gauging the weight of the laundry.
Laundry weighing will be done in a few spins, after which water intake commences with no delay.
A display shows the state of the machine. At least the following states are displayable: pre-wash, wash, rinse, spin.
A fast forward mechanism moves the machine to the next state.
A stop mechanism stops the machine in any state.
After the laundry is spun, the machine can spin slowly and reverse a few times to unstick the clothes from the drum walls, but this can be stopped and the laundry removed from the drum immediately.
The spin is braked so it doesn’t take minutes to coast down.
The temperature of the wash can be changed even if the program or wash has already started without having to reset or flush.
The spin cycle can be enabled or disabled even if the program or spin has already started without having to reset or flush.
Extra water can be enabled in the middle of the program.
etc etc.

All this was possible with seventies mechanical logic industrial washing machines. Note that almost all of it is pure logic whose cost is pretty much exactly zero once you’ve developed it, and other things like large hoses are trivial improvements.

If you will use this specification when designing a washing machine, then send me a machine: I will test it and say what improvements still have to be made.

Read Full Post »

Humans Fast, Machines Slow

Rand Simberg talks about impedance matching. So I’d like to make a post of my comment there (I’ve always wondered why this obvious alternative gets mentioned so little…)

What to do when you arrive at Mars or Earth with your solar electric propelled vessel?

So, the problem with most low fuel demand velocity change schemes is that they only give slow accelerations. Low fuel high velocity change means solar or nuclear electric propulsion and aerocapture mainly.

High delta vee aerobraking is hard to do in one pass – it gets dangerous because of atmospheric variability and potentially other reasons.

Simple: detach a small capsule with the humans that goes directly to the surface (with only days of life support) and leave the untended craft to do multi-pass aerobraking. Hitting van Allen belts a few more times or taking a long time doesn’t matter that much with no humans onboard.

You could also potentially ultimately leave the long distance craft at some Lagrange point instead of LEO. (Cue some clever and complex maneuvers to save fuel – maneuvers that take long.)

Something similar could also be done when a long distance stack is assembled in LEO: send the humans there only after it’s through the belts. They can go with a smallish capsule again. Potentially at some Lagrange point, or in space without any fixed reference, just along the way. It could be dangerous though if the capsule doesn’t have much life support.

Many of these things have potential delta vee penalties as well as timing inflexibilities, but they could have enough other benefits that they should be considered.

Read Full Post »