I'd like to point out to all thos who think that NASA overspends its budget the vast cost difference between developing something new, and buying a consumer product. The rocket engine which cost 20 billion for the first one is available "off the shelf" for 200,000 today. Same for "space rated" electronics, valves, cameras, etc. It's perfectly feasable to get a reliable payload working today for very little. It probably won't, however, do anything very innovative, because doing innovative requires high precision equipment which costs a lot on earth. The equipment also has to survive the takeoff, which is another matter.
Here's the original article
http://www.psychiatry.wustl.edu/Resources/Litera tu reList/august2000/406255.pdf
Since the researchers think that it's a response of spiders to chemicals. Here's the famous spiders on drugs experiment.
http://www.cling.gu.se/~cl5pwall/spiders/spiders .h tml
Looking at the pictures, I notice that a lot of the wires look very fuzzy. I'd think that these would bleed signal like crazy and be an impedence nightmare for non-DC signals. Still pretty impressive though.
An interesting point relating the article to the press release here:
In the article, it's all about bio-interfacing and what an advance this is. The press release says:
"One very interesting, albeit yet remote, possibility is to use these wires for electronic-biology interfacing," Velev said.
Not quite the same thing.
In addition, in the article, it broadly quotes a Professor Gerard Milburn. I find this quite interesting, in an article on biology and chemistry. He was my old Head of Department. He's a theoretical quantum physicist working in quantum measurement and quantum computing. Not my expert of choice in this field.
Note that with the matlab package you link to, that the processing does not take place in the matlab just-in-time-compiling environment. The matlab generates c code which you then have to compile. This is because bare matlab is (Generally speaking)too slow for real time operations.
The cheap option is then to write your own. The AD/DA cards you're using will probably have drivers and control libraries for the language of your choice. You won't get the fancy graphs, but if you set the thread priority high, it should work.
If the encoding time of the DA card is a problem, you should seriously consider doing at least part of your feedback in analog (Please don't flame me!). Simple analog computation: add, subtract, multiply, integrate, differentiate, timeshift etc is perfectly reasonable to do even at frequencies greater than 1MHz, and for considerably lower costs than a laboratory quality AD/DA card. You can always use a combination of analog and digital.
An interesting article, but it seems to rely on several strange arguments. I wouldn't agree that the accuracies required in manufacture and operation are not achieveable. It would seem to me that a fabrication accuracy of 1 part in 10^5 is scarcely unachieveable, especially since we have everyday devices, for example LCD monitors in which less than 1 pixel in 1 million is dead, and those are consumer products.
I don't necessarily buy his argument about the inherent fault-intolerence of quantum computing either, since it relies on the idea that a simple computer with no fault tolerence built in is fault intolerant! Scarcely a surprise. He didn't make a convincing argument that building in fault tolerance is impossible, only that it isn't being done in the simple designs he notes. Maybe I've misunderstood, but it would seem that this is an avenue for more research, rather than less.
It seems to me that in the end the whole of his argument relies on the engineering argument that we don't at present have any way to measure large numbers of single spin states (or indeed any single spin state). This would seem again to be an argument for more research, rather than less, since engineering serendipity is not a predictable mathematical process.
I understand his frustration that quantum computing is taking a lot of research funding from other areas, but I'd be a little more cautious than he is about saying that it definitely _can't_ work.
Just a general note on those scramjet tests. The guy in charge of these (Allan Paull) is my PhD supervisor, and I've been working in this area for about 4 years, though I'm not working on this project (I'm in Germany at the moment).
1. The tests were a failure in that supersonic combustion did not happen- That is, the engine operated as a ramjet rather than a scramjet. The first thought is that this was caused by the failure of the rocket turning manoeuvre, so that the air was entering the engine at a large angle from the main axis of the engine. Since the engine used has been tested up to 4 degrees of deviation, the angle was probably more than 4 degrees. The rocket needs to be turned so that it is facing downwards with the engine on the front. It should be able to do this due to the atmospheric pressure, but it turns out that it doesn't happen quickly enough. The rocket is a spin-stabilised type (Where the whole rocket spins, rather than have a separate gyroscope), and this means that the turning manoeuvre is a difficult problem in 3-D geometry.
2. Generally speaking, nobody (That I've heard of) in the scientific world is seriously looking at scramjets for a passenger plane. Amongst other thing, rockets have an unacceptable failure rate for general civilian flight.
3. The main proposal that I've heard is for a lifter of payloads in the one tonne range to near earth orbits. For that, scramjets should be cheaper than rockets. For the large payloads, rockets are still cheaper. There is a slight advantage with scramjets in that since most of the acceleration is done horizontally in the atmosphere, that a polar orbit is no more difficult to achieve than one on the equatorial plane.
4. In addition, though I'm sure there is research into scramjets for missiles (Of course it's not published in the open literature), there's not really a burning need to build faster missiles, since nobody is building faster planes or faster houses. Note also, that due to the air inlets, that a scramjet missile is inherently less stealthy than a rocket missile.
5. Somebody mentioned some tests in Russia. If these are the CIAM/NASA tests, then the papers I've read show all three flights operating primarily, in subsonic combustion mode. As ramjets.
6. One good reason for working in this field is because it is a discipline which brings together a lot of things that are also of use elsewhere. A lot of work is done on understanding the basic science, which feeds back into other areas. It's not really a field with a purely practical thrust at present, due to a continuing problem of not really understanding the aerodynamics at these speeds.
7. Thus the experiment which just failed was never really meant to be a working engine, but more a simplified example to use as a calibration for wind tunnels, and computer codes.
8. They used the terrier-orion rockets because Astrotech offered two of them for free. They have to get two tests under their belt before they can be generally licensed for testing in Australia. C/F new launch port at Christmas Island.
That's about all I can think of for the moment. The URL for the Hyshot project is:
http://www.mech.uq.edu.au/hyper/hyshot/
Slashdot Mirror
I'd like to point out to all thos who think that NASA overspends its budget the vast cost difference between developing something new, and buying a consumer product. The rocket engine which cost 20 billion for the first one is available "off the shelf" for 200,000 today. Same for "space rated" electronics, valves, cameras, etc. It's perfectly feasable to get a reliable payload working today for very little. It probably won't, however, do anything very innovative, because doing innovative requires high precision equipment which costs a lot on earth. The equipment also has to survive the takeoff, which is another matter.
Remove the space to make the address work, obviously.
Here's the original articlea tu reList/august2000/406255.pdf
s .h tml
http://www.psychiatry.wustl.edu/Resources/Liter
Since the researchers think that it's a response of spiders to chemicals. Here's the famous spiders on drugs experiment.
http://www.cling.gu.se/~cl5pwall/spiders/spider
Looking at the pictures, I notice that a lot of the wires look very fuzzy. I'd think that these would bleed signal like crazy and be an impedence nightmare for non-DC signals. Still pretty impressive though.
0 20 1.html
An interesting point relating the article to the press release here:
http://www.udel.edu/PR/UDaily/01-02/microwire11
In the article, it's all about bio-interfacing and what an advance this is. The press release says:
"One very interesting, albeit yet remote, possibility is to use these wires for electronic-biology interfacing," Velev said.
Not quite the same thing.
In addition, in the article, it broadly quotes a Professor Gerard Milburn. I find this quite interesting, in an article on biology and chemistry. He was my old Head of Department. He's a theoretical quantum physicist working in quantum measurement and quantum computing. Not my expert of choice in this field.
Note that with the matlab package you link to, that the processing does not take place in the matlab just-in-time-compiling environment. The matlab generates c code which you then have to compile. This is because bare matlab is (Generally speaking)too slow for real time operations.
The cheap option is then to write your own. The AD/DA cards you're using will probably have drivers and control libraries for the language of your choice. You won't get the fancy graphs, but if you set the thread priority high, it should work.
If the encoding time of the DA card is a problem, you should seriously consider doing at least part of your feedback in analog (Please don't flame me!). Simple analog computation: add, subtract, multiply, integrate, differentiate, timeshift etc is perfectly reasonable to do even at frequencies greater than 1MHz, and for considerably lower costs than a laboratory quality AD/DA card. You can always use a combination of analog and digital.
An interesting article, but it seems to rely on several strange arguments. I wouldn't agree that the accuracies required in manufacture and operation are not achieveable. It would seem to me that a fabrication accuracy of 1 part in 10^5 is scarcely unachieveable, especially since we have everyday devices, for example LCD monitors in which less than 1 pixel in 1 million is dead, and those are consumer products.
I don't necessarily buy his argument about the inherent fault-intolerence of quantum computing either, since it relies on the idea that a simple computer with no fault tolerence built in is fault intolerant! Scarcely a surprise. He didn't make a convincing argument that building in fault tolerance is impossible, only that it isn't being done in the simple designs he notes. Maybe I've misunderstood, but it would seem that this is an avenue for more research, rather than less.
It seems to me that in the end the whole of his argument relies on the engineering argument that we don't at present have any way to measure large numbers of single spin states (or indeed any single spin state). This would seem again to be an argument for more research, rather than less, since engineering serendipity is not a predictable mathematical process.
I understand his frustration that quantum computing is taking a lot of research funding from other areas, but I'd be a little more cautious than he is about saying that it definitely _can't_ work.
Just a general note on those scramjet tests. The guy in charge of these (Allan Paull) is my PhD supervisor, and I've been working in this area for about 4 years, though I'm not working on this project (I'm in Germany at the moment).
1. The tests were a failure in that supersonic combustion did not happen- That is, the engine operated as a ramjet rather than a scramjet. The first thought is that this was caused by the failure of the rocket turning manoeuvre, so that the air was entering the engine at a large angle from the main axis of the engine. Since the engine used has been tested up to 4 degrees of deviation, the angle was probably more than 4 degrees. The rocket needs to be turned so that it is facing downwards with the engine on the front. It should be able to do this due to the atmospheric pressure, but it turns out that it doesn't happen quickly enough. The rocket is a spin-stabilised type (Where the whole rocket spins, rather than have a separate gyroscope), and this means that the turning manoeuvre is a difficult problem in 3-D geometry.
2. Generally speaking, nobody (That I've heard of) in the scientific world is seriously looking at scramjets for a passenger plane. Amongst other thing, rockets have an unacceptable failure rate for general civilian flight.
3. The main proposal that I've heard is for a lifter of payloads in the one tonne range to near earth orbits. For that, scramjets should be cheaper than rockets. For the large payloads, rockets are still cheaper. There is a slight advantage with scramjets in that since most of the acceleration is done horizontally in the atmosphere, that a polar orbit is no more difficult to achieve than one on the equatorial plane.
4. In addition, though I'm sure there is research into scramjets for missiles (Of course it's not published in the open literature), there's not really a burning need to build faster missiles, since nobody is building faster planes or faster houses. Note also, that due to the air inlets, that a scramjet missile is inherently less stealthy than a rocket missile.
5. Somebody mentioned some tests in Russia. If these are the CIAM/NASA tests, then the papers I've read show all three flights operating primarily, in subsonic combustion mode. As ramjets.
6. One good reason for working in this field is because it is a discipline which brings together a lot of things that are also of use elsewhere. A lot of work is done on understanding the basic science, which feeds back into other areas. It's not really a field with a purely practical thrust at present, due to a continuing problem of not really understanding the aerodynamics at these speeds.
7. Thus the experiment which just failed was never really meant to be a working engine, but more a simplified example to use as a calibration for wind tunnels, and computer codes.
8. They used the terrier-orion rockets because Astrotech offered two of them for free. They have to get two tests under their belt before they can be generally licensed for testing in Australia. C/F new launch port at Christmas Island.
That's about all I can think of for the moment. The URL for the Hyshot project is:
http://www.mech.uq.edu.au/hyper/hyshot/