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If the steam was produced from a Hyrdogen Peroxide/Silver reaction (like Armadillo's Rockets) then a very fast compact underwater rocket might be possible. The volume and thrust of the steam from the Peroxide reaction would be amplified by the Jet effect to generate a large amount of thrust from a small amount of Peroxide fuel.

While i'm happy for them, this wasn't exactly rocket science. I'm surprised they had to roll their own connection pooling. This is standard in ASP/ADO apps and the new .Net apps. Caching the data is routine code you will find in most highly concurrent dynamic sites. Though, "caching" now adays goes a step further, generally XSL is used to build the page, and the result of the first XSL transform is cached to the file system. Some pages then go ahead and allow for an optional 2nd transform which puts in _very_ dynamic content, which can be shed/loss in the event of a traffic spike.

All in all, i agree with 90% of the posts, preventing a slashdotting is more about bandwidth then software/server performance. Yes, obviously hacked togeher asp/php pages that open and establish a connection to the database _per_ page will prolly die before bandwidh, i think even the newbiest of programmers recognize this nowadays.

This article made me yawn, but i bet we just paid his operational cost via add impressions for the new 5 months.

-malakai

Just an fyi:

As of the 15th of this month, they're still using PC104 over at Armadillo Aerospace.

As of yet, none of this is happening even though it is all very possible and we are just as capable of doing right now.

Actually, it's almost all happening, or being worked on (that is, if you want it that bad, you can go help make it happen, for you and everyone else, and get paid while doing so). Taking your examples:

I would also love free art,

I don't know about those who try to make their living from art, but I know that most of what art I have created has been given away. Granted, it's low production value, but it's been good enough for the people I made it for. There are a lot of indie artists out there who just give away their art - some of it very good, if you know what you're into and where to look for it.

obtainable medicines for those that need it,

Being worked on. (Aspirin, for instance, once cost a lot more than it does now. Or do you claim that even aspirin is too expensive for the masses? Follow the same trend with other medicines, and give it enough time.)

not charged to use the airwaves around me,

Talk to the FCC. They're floating that very proposal right now. (For instance, if no one's using a certain TV channel in a given area, the corresponding bandwidth becomes unlicensed in that area unless and until someone buys it.)

to be able to travel into space,

Being worked on.

and to be able to modify my own DNA at my whim,

I suspect you'd prefer to know WTF you're modifying first. That's the approach those who are working on this are taking: first, make sure those who would do it know what edits will have what results, then make it easy/cheap/free for everyone to do it. In short, being worked on.

However, NASA has been acting purely as a jobs program for the last 30 years, lacking vision of any but the purely political kind. The great majority of the NASA budget (some $3.4B a year!) is spent on space shuttle operations, not on research or visionary projects. The exploration missions get buried under the political weight of all those operations workers scattered across 50 states when budgets are developed.

Originally, the shuttle was meant to provide a cost effective means to develop vehicles that would launch from high earth orbit to explore and colonize Mars. Somewhere along the way the feeding frenzy began and NASA became just another sad beaurocracy.

I turned away from aerospace in 1994 after I sat with astronaut Guion Albert at an AIAA dinner, where we heard the NASA director of Aeronautics speak on the future of NASA. His name was Wes Harris and his vision consisted entirely of educating the underserved and enhancing their opportunities. This was the last straw for me and many others who looked to NASA to build the future in space.

Perhaps the recent amateur and commercial efforts in space vehicles like Armadillo Aerospace will give us the long awaited vision and excitement about our future in space travel...

Armadillo Aerospace News Archive

Flight Unsuccessful

November 12, 13, 15, and 16 (busy week!) meeting notes

We prepared for and conducted our first remote flight test at the Oklahoma Spaceport facility in Burns Flat this week. Several lessons were learned.

We built a checklist for our flight operations, which was a very good idea. Going through it before setting off caught several things we almost forgot.

The five hour drive from Dallas to Burns Flat was rougher on the equipment than expected. The tarp we put over everything to keep people from staring was damaged by the wind in several places, and the wooden cradle we transport the vehicle on actually broke one of its 2x4 support bars. We are probably going to arrange some hoops for the trailer so we can tarp it like a covered wagon in the future. I may consider an enclosed trailer with a suspension in the future.

Everyone was extremely helpful in Oklahoma, and we set up in the middle of a service road well off from the main airport runway. Our expected altitude with only five gallons of peroxide was under 1500', and our parachute drift range with 13 mph winds was only about 2000', so we had plenty of room. Bill Kourie from OSIDA stayed with us to communicate with the air traffic control tower during our launch activities.

Our setup was a bit slower than we expected, but everything got done fairly smoothly. The VOX on the radios we brought was more trouble than it was worth, often triggering with wind noise, but this was our first time using radio communication.

We did a full water test, then loaded up five gallons of peroxide. The engines all warmed quickly, and ran perfectly clear, even though it was in the mid 50s.

When we were cleared for our launch, I smoothly throttled up the engine over a two second period. The vehicle tilted a little bit on liftoff, but seemed to straighten out, but it then continued tipping, eventually tipping all the way over and flipping into the ground from a hundred or so feet up.

There was still peroxide left in the vehicle tank, but all the pressure had drained out by the time we reached it. We tipped it up to allow the remaining peroxide to drain down into the main engine and slowly catalyze away, then we carried the vehicle back to the road to run some low pressure water through it to clean it up.

flight video

We drove the remains to our bunker to strip off the good parts, and left the main body there.

http://media.armadilloaerospace.com/2002_11_16/bun ker.mpg Analysis

The telemetry cut off only four seconds after throttle-up, indicating that the computer died, but there was very valuable data.

Immediately after liftoff, there was a +Z angle rate kick, probably caused by the funny takeoff aerodynamics underneath the tail flare. The piece of aluminum sheet metal we put under the rocket for ground protection was folded in half and crumpled up after liftoff, which was completely unexpected. You can briefly see that in one of the liftoff video frames. The rate peaked at 22 deg/s, with the opposite attitude engine full on, then it started coming back down. The liftoff test last week did not show this behavior, but the feet were changed, and the surface was different this time. It is also possible that the main engine mount was slightly distorted by the travel.

The Crossbow stopped updating 1.25 seconds before telemetry ceased.

The vertical acceleration was right at one G when the Crossbow stopped updating, and very smooth. This was slightly higher than expected, indicating about 600 pounds of thrust from the engine at 280 psi takeoff tank pressure. The plumbing on the test stand was definitely limiting performance compared to the straight shot on the vehicle. The welded catalyst pack continues to perform very well.

The battery voltage started dropping rapidly at this point, but the computer continued operating for another 1.25 seconds, until the battery voltage reached 9v, at which point telemetry ceased. The 15v power converter for the Crossbow probably suffered a voltage drop before the 5v power converter for the main computer. The main engine feedback potentiometer reading fell off as the 5v supply dropped below 5v, and the engine pressure transducer started falling off faster than it should as the supply voltage dropped below 10v. All of this points to a general power system failure, rather than just a computer power failure (which has triple redundant connections to the main power supply from the manned lander work).

During the last 1.25 seconds of operation, the computer continued using the last valid Crossbow data, which caused it to hold the same two attitude engines on, which built up momentum on all three axis. Presumably the attitude solenoids all closed when the computer died and stopped sending an active signal to the solid state relay boards, but quite a bit of momentum could be built up in that time. The main engine would remain in the full-open position. As the vehicle did its flip, you could see it slowing down while it was pointed upwards.

The flight control code has in the past had stop-all-engines behavior when the crossbow stops updating, but on this flight there was no cutoff checks, which was a mistake. If there had been, the rocket would have just dropped from about 20' in the air, and suffered much less damage. The exact timing for deciding the crossbow isn't working is a tough judgment call, but a quarter second should certainly be enough time to decide that the attitude engines should cut off. The decision to cut the main engine is harder, because the vehicle should be able to continue flying as an unguided, aerodynamically stabilized vehicle if it is going fast enough, but right-off-the-pad, it could turn into a land shark.

There was one GPS update after liftoff, showing it at three meters above the ground, but with only a small vertical velocity. The processing latency on GPS velocity and position may be different.

My initial thought was that something had shorted, perhaps in the motor drive feedback or pressure transducer, which have power running to them from the main bus. When we opened the electronics box, the cable to the battery positive terminal was not connected. The battery still had full voltage in it, so we believe that the terminal came off during the flight, causing the voltage drop that led to the failure, rather than during the crash. It is unfortunate that it seemed to work during the water test and warm-ups, but the drive from Texas probably loosened the connection to the point that it was barely hanging on. The batteries have slip-on connectors, which have bothered me for quite a while, but screw terminal batteries are not available until much larger sizes. We are going to drill our own screw terminals in the lugs of future batteries, and possibly solder them as well.

The Damage

The important thing is that the Crossbow IMU survived, because that costs more than everything else put together, and can have an 8 week lead time. I am going to buy a backup, in case we aren't so lucky next time. Crossbow is now offering (but not shipping yet) an improved fiber optic gyro IMU with half the drift rate, but they jacked up the price a few thousand dollars.

The main tank actually seems to be ok, but we are not going to trust pressurizing it again.

The fiberglass nose and tail cones were both broken.

The engines casings for the parachute tower still look OK, I guess they bent away before the body hit them.

The tower was mangled, of course.

The pressure transducer at the top of the tank was broken.

Our aluminum engine frame at the base was bent a fair amount.

One attitude engine broke the jet holder fitting off inside, but we can probably remove it.

The main engine servo valve had the half inch pipe fitting permanently bent in it, but we were able to swap that section of the valve with scrap from a valve broken in a different way, so it seems to have been saved, but we haven't leak checked it yet. The plastic connectors on the valve were very brittle from the cooking they took on our hover tests that stuck to the ground, and broke when disassembled. We are going to run Tefzel wire all the way to the valve motors in the future, instead of using the supplied pigtail connectors.

All the plumbing survived, except for the two fittings that jammed in engines.

All the engines look ok, but we will have to carefully check that the main engine hasn't bent its inlet connector.

The WinSystems SBC computer seems dead. The memory SIMM was ripped out of the socket, which also partially detached, and even after reseating everything, it won't boot. The flash drive still works fine in another system, which saves me the effort of building a new linux system from my last backup.

The antenna connector on the Esteem wireless unit is broken, but the unit looks OK. Taking the case apart showed that we can save a large amount of electronics area and several pounds by just mounting the guts and ditching the case.

Both batteries have cracked cases, although neither one spilled any acid gel in the box.

The fan over the power supplies was wrecked.

The A/D breakout board was smashed by the batteries.

New Vehicle Work

We are going to proceed with the next vehicle design, as if this test had succeeded, rather than rebuilding an identical vehicle. The major change is to move to four large engines that are differentially throttled, instead of the single large engine and four solenoid controlled attitude engines. This goes back to the control style of our very first lander, and is motivated by the fact that we are bumping up against vehicle size limits for being controlled by the thrust we can get from solenoid based attitude engines.

The vehicle will pay much more attention to streamlining, with the intention of being capable of supersonic flight. The nose will be 10 or 15 degrees, and we will be using a honeycomb composite constructed box fin arrangement for stability instead of the tail flare. There will be no external protrusions or loose cables along the sides. We are going to try a rear parachute ejection system, with an intentionally crushable top nose section

The propulsion system will have a master cutoff valve, run by a separate watchdog computer. We have talked about this for ages, but not yet implemented it. If implemented on the last vehicle, it would have dropped it from a much lower altitude.

We are going to make many changes in the electronics to improve reliability.

There will be a backup 9600 baud telemetry radio, in addition to the Esteem 802.11b.

No more solid core wire for DB connectors, move to 22 ga stranded Tefzel wire. All 18 gauge wire is already Tefzel, but I had been using solid wire for soldering serial cables, which is a known poor practice. I am moving to mil-spec double-crimp terminals for all flight hardware, instead of the single-crimp industrial terminals we have been using.

Mount all the electronics, except for the inertial unit, on a vibration isolated board.

New A/D breakout board

The breakout board that WinSystems sells for their A/D board takes up a lot more space than necessary, and uses bare wire screw terminals for input, so we are going to replace it with a custom board that is smaller and takes ring terminals.

16 signal inputs with #6 ring terminals, one ground is common to all signals measured.

The range is +/- 10V, so we need to cut the main battery voltage in half before sampling. It is a toss up if this should be done on the A/D breakout board, or on the power supply board. There should be a grid of holes for soldering in random resistors or capacitors to modify signals.

The grounds are common to all the signals, so I think all we need is a single ground ring terminal that we will run back to the power supply.

The connector going to the A/D board is a 26 pin ribbon cable with the following pinout:

1: ch0 2: ch8 3: ch1 4: ch9 5: gnd 6: gnd 7: ch2 8: ch10 9: gnd 10: gnd 11: ch3 12: ch11 13: gnd 14: gnd 15: ch4 16: ch12 17: gnd 18: gnd 19: ch5 20: ch13 21: gnd 22: gnd 23: ch6 24: ch14 25: ch7 26: ch15

Watchdog Board

Trivial microcontroller that watches a continuous signal from the main computer, and uses a private motor drive to open the master cutoff valve only when the main computer is healthy.

Input:

One optically isolated digital line from the main computer

Private +12v / GND

Output:

Two #6 ring terminals to control the master cutoff servo valve (the main computer will still read the pot feedback of that valve)

Power supply board

Multiple, diode isolated batteries for redundancy, with an additional port for running on external power

External charging ports for each battery, so the electronics don't need to be taken out of the vehicle for charging.

Short run from batteries to boards, no in-line power switch. Use the power pin on the DC/DC power converters for switch-on. Use redundant switches to prevent a switch glitch under vibration from turning everything off.

Run nothing from the unregulated power supply, except for the A/D line for current voltage level. We previously ran a couple things from the unregulated 12v supply, like the Esteem wireless unit, and the pressure transducer. It is possible we were losing telemetry momentarily earlier than the computer died, depending on the details of their power use.

Instead of running wires from the power supply board to jumpered barrier strips for distribution as we previously did, build plenty of terminals directly onto the power supply board. At a minimum:

Lots of grounds.



Unregulated +12v: Battery A/D line

+5v: computer (two lines)

+5v: 6 motor drive potentiometer feedbacks

+5v: several spares

+6v: laser altimeter

+12v: pressure transducer

+12v: GPS

+12v: Panel-PC LCD display

+12v: Several spares

-12v: Panel-PC LCD display

+15v: Crossbow IMU

We might want to use a higher voltage for the IMU, as the range is 15v-30v, and we have been warned by someone about running avionics at their minimum recommended voltages. Today's result seem to corroborate that it is closer to going out than the rest of the systems.

Current draw signal for telemetry? If we ever have a short somewhere, this would be helpful in diagnostics.

Isolated voltage signals for each battery? If we don't have that, telling when a battery has failed will be difficult.

Actuator Boards

Our current solid state relay board still has bare wire terminals (although they are high quality ones that haven't yet given problems), it still has the old power supply on it that we don't use, and one bit on the input connector is flaky, so it needs to be replaced.

Isolated voltage signal for A/D telemetry?

Isolated continuity checks for each actuator? The motor valves can be self-tested by watching the potentiometer feedback, but solenoids and pyro would need a low-current test signal. The actuator battery needs to be completely isolated from the main battery to avoid noise problems, so a continuity sensor would need to be isolated as well.

We have known needs for up to six solid state relays and six motor drives, so building for eight and eight is probably good planning.

Nope. This was a conscious design choice, midway through development, but early Betas of the Doom engine ran just fine on a 286 (with enough ram). You can argue all you like about the excellency of protected mode operations, but John Carmack is a bloody speed freak!

It may seem obvious, but Quake 3 was the same way. When it first came out, nothing ran it well at all. Within a year, decent frame-rates were possible even with higher quality levels. Now Quake 3 is just like Quake 2 when Quake 3 first came out: any hardware on the market can run it at the highest detail level with no problems at all. John C. does this very much on purpose for two reasons. One: he can. And because he can, he makes games that look better, which increases his reputation, which makes it so that he can push the envelope even more. Two: hardware manufacturers love him (for obvious reasons) and make his job easier. I would also guess that leading the industry was fun for a while too (though I wonder if he's grown tired of it). At any rate, EVERYTHING id has ever done pushed technology to the limit, so I'm not quite sure why anyone is surprised.

I suspect that you are referring to the X-33, not the X-34. In any case, both the X-33 and X-34 were suborbital (goes up, comes down) spacecraft, so they could not have replaced the shuttle.

What really could've gotten us into space for cheap was the team that built the DC-X. That was actually built, for about 1/30th the price of the X-33, and it was a superior design to begin with. There's a video of it at Armadillo.

IMHO though, our best chance now is XCOR.

Carmack's Armadillo Aerospace (god, I'd love to go work for them :) tried to launch in Texas but couldn't get approval. They had to drive 6 hours to Oklahoma which is launch-friendly (if you give manufacturing preference to OK companies). There are many places that are offering alternative launch locations to NASA, but it's still tough to get approval.

Links: Armadillo Aerospace Log Entry and The Oklahoma Space Industry Development Authority

Go away and build something (or multiple things) small, but related, using technologies and methodologies that might be useful. Learn what works for you and what doesn't. Repeat a few times, until you know what's going to work for your project.

To give an analogy, look at what John Carmack is doing at Armadillo Aerospace. When he started out, he and his team didn't know enough about rocketry to decide what technologies they were going to use in their ultimate goal (a vehicle to win the X Prize for a private space shot). What did they do? They've experimented with a variety of things on test rigs and as part of complete craft, and discovered what works and what doesn't.

For a somewhat working version of their website try:

http://www.armadilloaerospace.com/n.x

Baldrson writes "Some guy named John Carmack wrote to the amateur rocketry mailing list "We finaly let someone ride on one of our landers. Only a few seconds in the air, but still pretty damn cool!""

The Stark Draper Open Source Rocketry Award (3 oz of gold for reaching 200km.)

and

John Carmack's High Performance Propulsion Award, $1000 for designing a rocket motor better than a certain performance level
(Seems to be down, at the moment, try the Wayback Machine)

/August.

Okay: Pessimist! Defeatist!

What I want to believe with all my heart is that there are, and will be, generations of hackers to work on such a project "Because We Can"(TM). Back in the cold war days these hackers received a lot of public funding. Right now they are on their own. But that doesn'tstop them from trying.

This is why I was so excited when "Junkyard Wars" became popular - it glorifies the engineers (at least the mechanical ones) in a way that is clearly needed, based on the nudniks who disparage Armadillo's efforts. We need more high-profile shows that go into serious detail about the creation process behind major engineering efforts - I'm talking actual series here, instead of one hour about how the Hoover Dam got built. I'd watch an Engineering Channel for hours on end if it existed. For example, I'd love to hear about all the setbacks and bugs they encountered when programming the computers for the first Apollo missions!

Go to Armadillo's web site and read some of their weekly reports on their progress - these guys are totally serious, and they know their stuff. What they don't know, they've learned, from the ground up - they started with very simple engines bolted to test racks, and they even dribbled peroxide onto various materials to test how they reacted (note to self: no leather shoes!). Along with the other small rocket companies, they're creating a new space culture that is unbelievably exciting - you watch, this is not a blip - more companies like this will spring up. This is the beginning of a whole new private space industry - at last the general public has the technology available to launch thing Very High. :)

To all the philistines, I've said it before - try to grow an imagination. It could prove useful someday.

This is why I was so excited when "Junkyard Wars" became popular - it glorifies the engineers (at least the mechanical ones) in a way that is clearly needed, based on the nudniks who disparage Armadillo's efforts. We need more high-profile shows that go into serious detail about the creation process behind major engineering efforts - I'm talking actual series here, instead of one hour about how the Hoover Dam got built. I'd watch an Engineering Channel for hours on end if it existed. For example, I'd love to hear about all the setbacks and bugs they encountered when programming the computers for the first Apollo missions!

Go to Armadillo's web site and read some of their weekly reports on their progress - these guys are totally serious, and they know their stuff. What they don't know, they've learned, from the ground up - they started with very simple engines bolted to test racks, and they even dribbled peroxide onto various materials to test how they reacted (note to self: no leather shoes!). Along with the other small rocket companies, they're creating a new space culture that is unbelievably exciting - you watch, this is not a blip - more companies like this will spring up. This is the beginning of a whole new private space industry - at last the general public has the technology available to launch thing Very High. :)

To all the philistines, I've said it before - try to grow an imagination. It could prove useful someday.

Have you discussed rocketry with John Carmack and his friends at Armadillo Aerospace? They plan to eventually fly a manned rocket as well.

Yeah, it's not as if building an X-prize level rocket ship doesn't have any world-changing potential.

Its good to see progress from some of the small launch vehicle companies, especially after the failure of Rotary Rocket.

The actual success here, though, is perhaps not as revolutionary as it first appears. The DC-X had a similarly reusable and relightable rocket even though it was in a more conventional vertical 'rocket ship' design.

Getting cheaper access to space is the key to broader space tourism and proper space industires. Other companies trying this include Pioneer Rocketplane, Armadillo Aerospace, JP Areospace and TGV Rockets to name but a few. There's even a UK outfit, Bristol Spaceplanes,
and the European Space Agency is beginning to think in this direction too, according to CNN.
All the companies are small and desperately in need of money if anyone wants to invest. Its probably less risky than Worldcom!

Another useful resource is the Space Access Society. Indeed they've argued that the whole X-33 mess was in fact Lockheed-Martin protecting their lucrative disposable launcher market by messing up the project. Sadly, NASA seems to have been complicit in this.

LOX liiquid fuel systems are indeed complex. Peroxide systems on the other hand are simple. Anyone with access to machining tools could build one in an afternoon. The basic design requires a presurized fuel tank supplying a jet that sprays the peroxide through silver screens in the reaction chamber of the thruster. Lenght of flight can be determined by adusting the pressure in the tank and the flow through the jet. Check out the lander the guys at http://www.armadilloaerospace.com/are developing. The controls are complex the basic design of the motors is not. Try Google for more peroxide rocket motor designs. You'll see what I mean.

that our fellow Slashdotter/Linux nut/3D guru John Carmack isn't launching his XPrize contender. For those who are not following his adventures in amateur rocketry, a few years back he started a company called Armadillo Aerospace which is a hobby project of sorts. They have created prototypes for hydrogen peroxide powered landers and are working on a suborbital launch in a near future.

It's not in quite the same class but John Carmack's space exploration plans are pretty good (and a hell of a lot more realistic). Keep up to date here.

From the material reactivity testing video, it doesn't look like there will be a business class section on their rockets any time soon (peroxide + leather = FIRE!)

The cost of a working moonbase would be well over $300 billion dollars, and would take at least twenty years.

Did you pull those figures out of your butt, or are you quoting any particular study? The International Space Station is only going to cost a fraction of that, and that's largely due to it being a huge orbiting pork barrel. Returning to the Moon is obviously a bit beyond John Carmack just yet, but well within China's reach if they set it as a national priority.

The world has moved on since Apollo, but everybody seems stuck with the concept that spaceflight is only ever going to be a national project on a pyramid-building scale. It's still going to be expensive for quite some time, but the fact that we don't have to reinvent the wheel, compact computers, carbon fibre or Tang helps keep it a bit more affordable than the '60s NASA program.

There are several groups looking at private Moon exploration, Artemis being perhaps the most well known. I think that they are kidding themselves, but good luck to 'em.

No, seriously. Did you pull the figures out of your butt?

To follow the true path to space you must not be mislead by false hippocracy such as this eBay conspiracy. The true path lies in pioneering. Look at the golden carrot from the x-prize and true seekers of enlightment such as the armadillos and the canadian arrow. True pioneers to space.

Show me the real rocket and then we can talk.

Low bandwidth: http://media.armadilloaerospace.com/sff_low.mpg and http://media.armadilloaerospace.com/sas02_low.mpg

High bandwidth: http://media.armadilloaerospace.com/sff_high.mpg and http://media.armadilloaerospace.com/sas02_high.mpg

And just to plug my own group's rockets: http://cube.erps.org/movies/.

Show me the real rocket and then we can talk.

Low bandwidth: http://media.armadilloaerospace.com/sff_low.mpg and http://media.armadilloaerospace.com/sas02_low.mpg

High bandwidth: http://media.armadilloaerospace.com/sff_high.mpg and http://media.armadilloaerospace.com/sas02_high.mpg

And just to plug my own group's rockets: http://cube.erps.org/movies/.

Show me the real rocket and then we can talk.

Low bandwidth: http://media.armadilloaerospace.com/sff_low.mpg and http://media.armadilloaerospace.com/sas02_low.mpg

High bandwidth: http://media.armadilloaerospace.com/sff_high.mpg and http://media.armadilloaerospace.com/sas02_high.mpg

And just to plug my own group's rockets: http://cube.erps.org/movies/.

Show me the real rocket and then we can talk.

Low bandwidth: http://media.armadilloaerospace.com/sff_low.mpg and http://media.armadilloaerospace.com/sas02_low.mpg

High bandwidth: http://media.armadilloaerospace.com/sff_high.mpg and http://media.armadilloaerospace.com/sas02_high.mpg

And just to plug my own group's rockets: http://cube.erps.org/movies/.

Some of them were. Check http://www.armadilloaerospace.com
for details.

....PURE copper runs 350-400 W/m-K...pure copper isn't usually used, an alloy is.

I was talking about copper alloys. At room temperature, Both copper 110 and 101 alloys have a thermal conductivity of 391 W/m-k. Phosphorous laced copper alloys will drop you down to around 380. The only reason I happen to have these numbers is I'm currently working on a heat sink.

The news article that got this thread going had so many inaccuracies that I'm prone to think that a marketeer at Poco got somebody at ABC News all excited with hype. Given the foam's poor thermal conductivity, I seriously doubt the national security agency is using it as a heat sink unless, possibly, it's on a satellite. But if that were the case, Poco would have been nda'd and the story wouldn't have made light of day. The story smells of marketeer-speak.

You're right about the density uneveness. There are several elemental foams available that have very uniform density. You can get metal silver foams for applications where surface area is very important. John Carnack (of doom fame) has been playing around with silver foams as a catalyst for hydrogen peroxide to drive his rocket.

However, as a heatsink, foams don't fare well because heat transfer is partially a function, not of surface area as you assert, but of the cross-sectional area perpendicular to heat flow. Foams have lots of surface area which is nice for catalysts but have lousy cross-sectional areas which is what is needed to transfer heat from one edge of the foam to the other. Once the heat is spread out over a heatsink's mass, THEN the heatsink's surface area comes into play. Foams suffer as heatsinks because they can't move heat well from the primary hot spot to their extremeties.

Having said all that, there's some experimental work going on with carbon heat sinks that are configured in standard heatsink geometries. Anandtech's Cebit report shows a few pictures of some carbon heatsinks. Carbon is attractive, because as an element, it does show promise. As a working material, it's difficult. If carbon nanotubes ever get out of the lab, there'll be a huge change - they've got great thermal conductivity - somewhere in the thousands of watts.

One small problem though, is that they don't actually have a sub-orbital craft yet.

Just such a horrible thought! Making NASA accountable for what it spends!

After all look at the blazing fiscal successes of the International Space Station and it being able to come in under budget!!!

Or the success of the X-33...

Or X-34...

Or the X-30...

Or how about how the shuttle and how much it brought down launch costs just like they said it would...

Maybe there is a theme here, huh?

Perhaps when NASA learns some fiscal responsibility then we'll get our mission to Mars from them. And it's quite possible the wonderous big budgets of Apollo aren't EVER coming back.

In the mean time, it might actually be others who get there first. And, no, I don't mean other nations. John Carmack (yes, that John Carmack) is working on his one rocket company:here and Jeff Greasona nd crew are working on their own stuff here.

I might just wanna give them some competition myself...;)

Actually, he's building a spaceship.

JC makes himself VERY accessible to the community. Not only in his .plan updates (which are currently far and few between, probably to try and minimize hype for "DOOM3"), but he also regularly attends conventions and LAN parties, along with also giving workshops at them as well. And also appearing at keynote speaking events, then you have interveiws, written interviews, slashdot postings, not to mention the videos and blurbs on www.armadilloaerospace.com[armadilloaerospace.com] etc. etc. etc.

Celebrities give up a good measure of anominity and privacy, the same is true for the people that develop the games we play and lovel. I'd bet dimes on the dollar that JC (or any of the Id staff for that reason) probably can't go out to dinner without at least one person wanting to stop them to talk. It's alot of pressure to be under, so I wouldn't at all be surprised if he gets a little aggrivated now and then. Romero is known to be a very good natured, and accessible person, but do you think he doesn't get aggrivated at times and just wishes that people would leave him the heck alone? Of course he does, but him and JC are different people. They will react to different circumstances in different ways. Neither you, nor I have any qualification to say which is right or wrong until you walk the miles in their shoes

I've never met the man myself, but you've only met him once. Don't presume that can really sum him up by one short meeting in a crowded convention hall, where there is serious pressure to give attention to as many people as possible, which could be hundreds during events like that.

"I don't want to get locked into signing these all day"

Perhaps you failed to consider that maybe he simply didn't feel it would be fair to sign yours for you, and then ignore other people due to simple lack of time. It was very gracious of him to sign it for you, he would probably feel a bit guilty if he didn't sign something for everyone after that as a result.

TROLL MODE ON - in summary: Stop being a selfish and judgemental prick. You don't know anything about the guy.TROLL MODE OFF

If people flock to his words, it's mostly because he tends to make sense, and back his words with hours upon hours of coding. Much of that code ends up being released under the GPL, so you can actually see for yourself whether it's any good.

How can you forget about Armadillo Aerospace? You might know the name of one of the members of the team: John Carmack . They are very serious. They have a few flight test videos, and they have a few prototypes that could carry a person (Though that spot was filled by a punching bag for testing purposes).

Check out:

Armadillo Aerospace

Comment by JC about his rockets (Hydrogen Peroxide-based, by the way).

Their demonstration video(quite impressive).

How can you forget about Armadillo Aerospace? You might know the name of one of the members of the team: John Carmack . They are very serious. They have a few flight test videos, and they have a few prototypes that could carry a person (Though that spot was filled by a punching bag for testing purposes).

Check out:

Armadillo Aerospace

Comment by JC about his rockets (Hydrogen Peroxide-based, by the way).

Their demonstration video(quite impressive).

The BBC and CNN do it again. They oversimplify matters so that they sound like better news than they actually are, in order to satisfy their increasing market of people whose IQ is slightly lower than their shoes size. At least this article didn't twist the facts like the BBC has beeng doing during the last few months (I still can't figure out why, and the whistle has been blown broadly).

I'm pretty sure this guy is running low on cash so he hurried up this test in order to get some media attention that would help him get some more funds. It doesn't really matter really, since I already know who's goign to win. That will be Armadillo Aerospace

They had a crash a few months ago and have recovered very well. their plans are the opposite from what most of the other contestant's are doing. They're working on a design that revolves around the ability to seat people on it, instead of trying to get higher than anyone and then picking up the parts. Actually, now that I think of it, I don't even think they're doing this for the prize, which makes them even better candidates.

Of course, now I am also oversimplifying things, but at least I don't make money doing it, so I encourage you to go to John Carmak's site and check out the logs. Maybe someone here can help out with those Windows ME features he's been having problems with (check out the last few log entries)

Hey, I have an idea:

Fly more rockets using all that computer and electronics skill for cool hacks in guidance and control maybe even with some rocket races and some rocket designs that can use the guys in high performance automotive shops to lower cycle times on design and development.

I find it unbelievably strange that John Carmack (of Doom,Quake fame) is also building a rocket capable of transporting humans. He's made a ton of progress. His company: Armadillo Aerospace

http://www.armadilloaerospace.com/

I'm even more frightened when I consider that future space exploration may be limited to Individuals and Private Corporations, whose main concern is their own pocketbooks, and not the benefit of humanity.

You mean like John Carmack?

Because I know he's reading. :)

What is your team's ultimate goal? Your web site states that you want to have "manned rockets", but do you want to achieve orbital space ships? Just ships to fly to 7-11 and back? Moon flights?

And is this just a hobby to you? What about the future? Can you ever see rolling your current hobby into a future aerospace company?

--

Carmack's team is building a VTVL rocket, but it's A) manned and B) intended to just do hops. It's intended to be a technology prover, but it's going to be more like a flying rocket chair than a spaceship.

Plus, his budget is at least an order of magnitude less than the Japanese budget.

Who says Americans can't do small and cheap? Go John Carmack!

Jon Acheson

We will have a manned rocket vehicle flying by the end of the year, but it will be a modest little thing. The performance will only be about what you got out of the old Bell rocket pack, but it is fully fly-by-wire (and can be tested remotely) with active stabilization, and all the subsystems are directly scaleable to much larger vehicles.

I will probably enter as an X-Prize competitor at that point.

John Carmack
Armadillo Aerospace

http://www.armadilloaerospace.com/ElectronicsBox_f iles/image002.jpg

Viewed source on the webpage. It wouldn't load from the page. It's full of wierd XML stuff. Maybe that's the problem.

Could be.

From Early design notes for the first manned vehicle:

Near term stuff to get / work on

• ...
• PVC bunny suit
• Life preservers
• Helmet (I have one)

You can see parts of Carmac's Ferraris on this picture! http://www.armadilloaerospace.com/Vtvl2.jpg