Because the government (is supposed to, anyhow) takes the request, pulls any and every document that matches the criteria in the search, then goes through those documents
Some get marked "classified" instantly. Some of the classified stuff may actually get downgraded (because of age or lack of relevance in the current time period). Some formerly public stuff (that at one time was classified, then made public later) has actually been made classified again. In some cases, this was wholly successful (and we will never know what cases those were), all public copies having been retrieved or destroyed. In other cases, the public has won (or been sceded to) - such as the case of the Economist and the H-Bomb plans...
Those papers that are allowed through, then have to be copied, read, blacked out (ie, redaction), then copied again. Most of the stuff isn't even on computer - it is still large warehouses of paper and tons of copy machines.
One huge, ancient, creaky and wasteful system - just like every other part of our lovely government...
...haven't read all the comments, so take this remark with a grain of salt.
Something people here seem to be wondering is how this system will compare in safety of preventing ground explosions of the shells (in the event of a misfire or other mishap).
Something that I hope a lot of you know about is that the shells used in many displays are becoming very sophisticated. For a couple of years now they have had microcontrollers and other electronics in the shells, which can be programmed to cause the shells to do various effects (almost to the point of a custom effect shell). Some of these effects allow for timed designs - if the shell goes off right, you now have an expanding circle of "pixels" - so of you may have seen happy faces and hearts and similar designs done with shells. The microcontrollers can be programmed right before the launch to know when to explode (time or altitude based). I wouldn't be surprised if they don't have RF-based (hopefully over a secure encrypted channel) detonation. Perhaps even in-flight reconfiguration?
Fireworks have recently become really high-tech, thanks to virtually throwaway low-power microcontrollers which are small and easily integratable into the shell. While none of this removes the possibility of a ground explosion, it does help lessen it (electrical ignition rather than timed fuse), and allows for more impressive effects and displays...
One possible solution would be similar to the Flogiston Flowstation approach, except slightly larger: position a lounge-style chair so that it (the headrest area) is "enclosed" by a large (1 meter diameter?) hemispherical rear-projection "dome". The user wears shutter goggles (for the 3D), the projection is done using a high-frequency (100 Hz+) XGA projector, back projecting on the dome.
Spatial warping would be accomplished either by lenses or software (to "flatten" the image back out, caused by distortion of the curved surface of the projection screen).
You could probably build such a workstation for under $10,000 (the projector will be the expensive part, not to mention the custom back projection screen).
External rendering boxes are nothing new - Evans and Sutherland have been doing this for years with their high-end OpenGL rendering hardware for simulation use. I don't know what their current hardware uses (or if it is still external), but they used to use a SCSI-based bus system...
I find that if I were to be an American, it would be very hard for me criticise the President. From what I know that sort of thing is just not done. Being patriotic is good, but IMO criticism is the basis for a good democracy.
Don't confuse patriotism (ie, a questioning attitude toward leaders, wanting them to represent you, etc) with nationalism (ie, never questioning or fearing to question your leaders, etc).
What many people here in the US think is patriotism (and have been spun to as patriotism), is nothing more than pure nationalism.
Patriotism is a good thing - nationalism can easily lead down a very bad and dark road (just ask anyone over age 50 or so in Europe or the UK)...
Something that rarely thought about until it is encountered in the actual system, is projector registration.
There are basically two kinds of CAVE projector setups
1. A single, high-frequency (read that as big $$$$) projectors (120 Hz+), which use "flicker goggles" (though at these high frequencies this is rarely an issue) - like CrystalEyes glasses or something similar.
2. Dual projector systems (lower frequency projectors are cheaper) which use polarizing filters and similar glasses, each projector getting a different view from the rendering engine PC for the 3D effect.
The problem with the second system, while it can be cheaper (plus you don't have to deal with issues of wires or batteries in the glasses, just use cheaper polarized glasses - nearly throwaway), is the problem of registration - how do you get both projectors to overlay the image the same on the screen without undue distortion (keystoning) - if you place them side-by-side, you have an issue, same with on top of each other (plus there are ventilation issues, but that is another topic).
Ideally, you would want to use a prism or something to combine the sources - but this opens up other expenses (as well as light-loss issues, which will already be an issue with the polarizing filters).
Just keep it in mind as you build or consult on this system. The registration issue may not seem like much, but it can easily cause eye-strain and other issues when in use, and you will already be fighting physiological symptoms (ie, simulator sickness) just because it is a full or near-full immersion system...
Your graphics hardware isn't the problem - we all know that a very decent rendering engine PC can be had for almost nothing. Let's say dual-head, high-end process, ram out the door, etc - probably do it for $2000-3000 (and that is a very liberal guesstimate - likely the final PC will be a lot cheaper).
The software is cheap/free, too - plenty of options there, from modded UT and Quake offerrings (among others), to Python/PyGame/OpenGL combos.
Where you will be hit is the HMD/output end. If you are willing to go with a lower resolution (640x480 - 800x600), there are plenty of offerrings on Ebay and elsewhere - you have to know whether your app will need immersion (60 degree H x 45 degree V FOV minimum), or if you need resolution (always a tradeoff). If you are looking for immersion (personally, I always prefer to be immersed - its VR, not looking down a tube!), look into a Visette 2 or Visette Pro HMD. These HMDs could be termed "arcade" or "prosumer", or low-end research HMDs - the Visette 2 HMD was used on the Virtuality 2000 series pods, and can be found used. One caveat though, it needs PAL (composite) video inputs. The Pro version takes SVGA.
Try to "try-before-you-buy", if you can (very difficult, I know). For the Visette 2, go to Vegas or a theme park and look for the Virtuality "VR Arcade" or whatever they call it, and try it out (stay away from the older Virtuality 1000 pods, the HMDs are heavy, and low res - but great FOV).
At any rate, you should be able to pick up an HMD for under $1000 if it is used (I have bought both a Visette Pro and a CyberEye CE-200M HMD for under $300 each off ebay). A new HMD like that will run from $1500-2500.00. A final option would be to build the HMD yourself - easily doable, people did it all the time back in the early 90's using handheld casio TVs.
The nice thing about the Visette 2 HMDs (off an actual Virtuality pod), is that they have Polhemus receiver coils built-in - meaning that you can easily interface them with Polhemus 6DOF tracking systems. Same with the Virtuality 2000 pod's joystick.
Tracking is where you will also run into money issues - expect to pay around $2000 for a good tracking system. If you just need head movement, though - and can live without "roll" of the head (only yaw and pitch), look into modding a GyroPoint GyroMouse for the application - simple, and cheap 2DOF head tracking. There are also a lot of simple tracking possibilities that can be homebrewed, as well - but if you want a commercial system, expect to pay some money.
Now, as far as gloves are concerned, you would probably do best to get a commercial 6DOF tracking system (put the sensor on the back of your hand or wrist), then buy some lycra gloves, sew some brass button "snaps" onto the fingertips and palm, and make a "pinch" circuit recognition system (rather than tracking finger bend - unless your app requires it). Gloves will run you an arm-and-a-leg - they are so niche (and still locked up in patent issues from the VPL patent set - it was a very broad and large patent suite that VPL had). You can spend a lot here. Roll your own, if you can (and if you aren't selling a product - most any glove that you homebrew will stomp on a number of patents). Another possibility is to hack up/apart a powerglove for the flex sensors, then sew them into/on a lighter lycra glove...
If you aren't going to want to "look around" your world, then simple shutter glasses, like they sell for game systems, can be had for cheap - and you don't even need dual monitors for it. If you want something more professional, a CrystalEyes system would be best, but be prepared to spend some cash.
Even if you go completely professional (and stick with a regular PC and free/open source VR software solutions), you can easily do this for under $10,000. If you really take your time, you can easily do it for much less (remember, homebrew VR on PCs used 386's back in the early 90's - cost for a VR setup really hasn't changed much if you homebrew all or most of it - its only when you bri
If it is coming straight down, all that mass is going to slam into the water - I wonder what kind of tidal motions that would set up, and how bad it would be for shoreline communities? I suppose it would depend on where it was situated - the further out from land, the more energy the wave will expend before it reaches land - but you wouldn't want it too far from shore, as you need to economically get people to the loading platform/dock...
Once you have the elevator, make water part of the mass, and shielding all in one go - once at the platform, it could be stored for later processing into fuel, or use it for drinking, or space-based agriculture...
Ever been to a high-power rocket launch? I have, and I felt safer during these launches than I did during many of the nearly unsupervised Estes rocket launches I did as a kid.
Nothing is dangerous if it is respected for what it is and what it is capable of. It is only when you mix ignorance, stupidity, or willful disregard do you get "danger"...
Does he store gasoline? Does he store flour (flour dust is highly "explosive")? Does he store pool acid (which, along with alluminum, well...)?
Hell if he owns an automobile he has a ton of explosive potential at his house (big gas tank full of gasoline, plus that potential energy storage "tank" we call a battery - oh, which also vents hydrogen and other flammable gasses)...
Storage of explosives at home is a strawman argument...
Hybrid rockets are a start - the problem with the current crop (NOX + "plastic" fuel) is getting the NOX (not super-easy to get, nor cheap), plus the whole setup actually seems pretty dangerous (I have seen a high-power hybrid launch - the guy launching it stood next to the rocket, filled it up - when the countdown was ready he waved, turned the valves off, removed the hoses, then ran like hell - to get clear of the rocket before the ignighter hit).
I am wondering if an inversion of this could be done - compressed gasoline or kerosene (or some other flammable liquid - methonol or something), "pumped" (the pressurization of the liquid would do this - pressurize it with an air compressor or hand pump) through a solid-fuel oxidizer core (perhaps ammonia nitrate fertilizer-based?)...
Not sure if this would work - and I am not crazy nor experienced enough to try it out...
Have you ever been to a high-power rocket launching? These aren't "slap-together" missles. Many of these rockets take several 10's to hundreds of hours to put together - spending anywhere from $500.00 to several thousand per rocket is not unheard of. Many of the people involved are rocket scientists and engineers in their day jobs - others are involved in other highly technical disciplines, and got their rocketeering chops from flying their own stuff. These guys know how to build big and safe engines from simple sugar (so-called sucrose or candy loads). The people involved know each other as a group, and work out trading skills and such - this guy needs and engine built (candy fuel in a PVC or alluminum tube), so he trades that for his skill at machining a nozzle from graphite or alluminum on a lathe. The launch pads themselves use pieces of alluminum rail that is pretty expensive (most of it is 80/20 style extruded alluminum). Transport, setup, and takedown is a relatively long process. None of this is cheap - not the materials, not the rockets, not the knowledge.
I can't imagine a quick salvo being built and fired off perfectly. During the launches I have seen, more than a few failed on the pad, many failed mid-flight. I have seen video of launches that exploded on the pad (without the help of explosive tips). Lastly, none of the rockets I saw went 60 miles - hell, none broke 20,000 feet, nor went out of the flying envelope secured for the days (pretty large volume, too).
That isn't to say that these things couldn't have been made to be missles - but the expense and expertise required to do so is huge, so huge it hasn't happenned yet, despite high-powered model rocketry being around for well over a decade (and model/experimental rocketry being around for much, much longer).
Finally, for the people that do this - it is a hobby. These are guys (most are grown adult men with maxed out credit cards or other funding) who instead of buying a motorcycle or a boat, build large and expensive rockets to fly and amaze their peers with. As a spectator, I have found it to be an incredible and exciting hobby. It tempts me to get involved in it - I just can't afford it (either monetarily or time-wise)...
I think you mean a "cornea scan" - not a retinal scan.
Unless things have changed lately (I don't kepp up with this stuff, so I suppose they could have), retinal scanners usually require the user to look into the device, which then uses suction to "suck" the camera against the eyeball and hold it in place (very still) so that the camera can see into the eye and quickly capture an image of the retina for comparison purposes.
From what I understand, it is a very uncomfortable thing to go through, so you only see them being used in very-high security environments. There is also the issue (with any kind of eye scanner) of risk of infection (pink eye, styes, etc) to multiple users. Both of these issues, together (not to mention high cost for the scanners - though this might have come down) limit the use of the devices to mainly niche markets...
To an extent (in the end, it is the malware authors ultimately who are responsible, though, regardless of the end user)...
They may be "scared shitless and completely ignorant" - but there are two types of ignorant people: stupid-ignorant people who throw their hands up in the air, and say "oh, well - nothing I can do about it" or fret over the problem, and intelligent-ignorant people who say "Damn, why is this happenning?", and then seek out sources of knowledge, using the internet, library, bookstore, friends, etc - to come up with an answer, a solution, and then learn (thus losing the ignorance of the problem) - so that they have a future more enlightened and knowlegable view of computers as a whole.
Unfortunately, most computer users fall into the stupid-ignorant category. Furthermore, it not only affects their daily computer usage patterns and "knowledge", but their entire life. These people seem incapable of using logic and reason in a manner which increases their knowledge base on any subject. These are the people who don't seem to understand that you need to change your oil and shocks on your car, or that timing belts need to be replaced (lest it breaks causing massive damage to the valves in your interference-style engine - big bucks for the machine shop). These are the people who buy brand new houses in brand new subdivisions with brand new HOA agreements (for brand new ultra-high prices) - then get angry because the HOA fines them for having grass an inch higher than it should be (one would think they would have read and understood the terms of their contract, and what they were getting into) - oh, yeah - and the house is built like a cardboard box that can have a golf ball knocked through it...
I don't pity these people - I openly laugh at them. I have tried to educate them, but the knowledge that I try to impart upon them just sails between their ears - you can damn near hear the hollow echo of the wind from their heads, as you gaze at the empty and far-away expression they wear on their faces.
Hell, even sheep look more intelligent at times...
At one time (when they started), Best Buy's marketing pitch was that the sales people would go out of their way to leave you alone - they would only help you if you asked for it.
Has this changed? I haven't been in a Best Buy in over 2 years (last time was while shopping for a freezer - ended up buying one at Lowe's)...
Actually, if I remember the case properly, said customer of McDonalds actually put the cup (with lid) between her legs, near her crotch - I can't remember if she was the driver or the passenger.
Now, I don't know about you (some people can stand it), but hot water (ie, hot water from your water heater for a bath, say 125 degrees F) doesn't feel good in the crotch area. This *should* be common sense. It should also be common sense that to make coffee, you need to boil it, then keep it hot (at least 125 degrees - which is still hot enough to "burn" the skin - maybe not physically as in "going to the hospital", but it can be painful) before serving it (iced cappucino notwithstanding, of course).
Now, McD's did make it very hot (180 degrees F, IIRC) - but even so, even if it was "bath water hot" - that would still have been hot enough to potentially hurt.
Common sense should tell you not to put hot liquids (ie, anything over say 115-125 degrees F) on or near your crotch, lest they spill, and at a minimum cause some pain - or worse.
This woman gambled by doing something really stupid (even if it was cold liquid - you don't want to put it there because it could either freeze the jewels, or spill, leaving a wet spot, leaving others to wonder whether you urinated on yourself - not a good social situation, right?) - and she lost big time because the coffee was extremely hot (2nd degree burns?).
Honestly, I think she and the jury screwed up - she should not have gotten any compensation. There wasn't any negligence on the part of McDonalds - they didn't spill it on her. They simply brewed the coffee (which involves using boiling water), then kept the coffee at a high temperature (but well below boiling) to keep it tasting good (well, as good as McDonalds coffee can taste - eh) - I would be willing to bet that the majority of restaurants, at the time, did this as a matter of standard cooking practice. They served it in a cup with a lid (now, if the lid was loose - which I can't remember if it was - then that could be an issue - but common sense has always told me the first thing you do at any two bit fast food joint, when you get your drink, is check the lid on it - followed by checking your order in the bag to make sure it is all there). This is all standard.
When the woman decided it was a good idea to put the coffee between her legs, knowing it was hot, without verifying the lid was on correctly - how can the producer be liable?
So nowadays, we see all sorts of disclaimers on our food: "Caution! The food you are about to eat is hot!" (no shit, like I paid for cold egg rolls), etc.
I am waiting for the day they put a warning stamping (a sticker wouldn't last), and/or color markings, on or near the tailpipe of an automobile "Caution: Tailpipe is HOT!!!" - Here's your f'ing sign, you Amerikan sheeple.
I understand the original poster's frustration, though - you know how many years we had to wait and wait for a "TV that hangs on your wall" - before they finally became available to the general public? 15 years? 20?
It was always "next year"-this, "next year"-that. The bad part was that we didn't see any incremental products. The best we ever got to see was a few limited applications in LCDs on laptops and other similar computer devices - but there were viable small-screen LCD displays for video use long out (on laptops) before they were being sold to consumers. We could have gotten LCD monitors (granted, on 15" or smaller, likely) long before we did - but the f'ing corps had to make every last penny off of CRT's...
In the case of private manned spaceflight - it wasn't really a case of who was going to be able to do it, but who had the balls to try. Furthermore, we (the public) have been able to see the incremental advances necessary to get where we are today in this field - much of the tech behind Rutan's ship (mainly the engine - NOX hybrids) has been available to high-power rocket enthusiasts for a few years, at least.
McDonnell-Douglas, or any of the other large, private satellite launch platform companies - could have easily (still can) sent a man into *orbit* atop one of their launch vehicles - the rockets are more than capable, they just don't have the balls (that, or they can't get the insurance for a reasonable price) to do it.
Maybe now with Rutan's first success, we will see these companies actually trying something with the tech they have.
But for all of this other technology - much of it is either vapor, or they are milking every last drop of profit out of the old technology before they release the new stuff...
If you want something like this, it is fairly simple to do (for different values of "simple", of course).
What you basically want is the rear half of a motorcycle, and the front half of a lightweight, rear-wheel and engine car - an old VW bug would probably be perfect, but a Toyota MR2, a Fiero, or a Honda Del Sol would work well, too (and be lighter weight).
All of these can easily be found in junk yards, so find a running (but with front end damage) used motorcycle, with a larger engine (something to push the extra weight. Cut the front off the car, and with a lot of welding, cutting, torch-work, and some steel...
In the end, you can have what you want - basically, it is the reverse of the 3-wheel motor-trikes you see every now and then (which use the rear of a VW bug most of the time)...
Unfortunately, the application has to be real-time, or near real-time sampling rates, for a large number of sensors. Post-processing the data is not an option.
I have done this - but thanks for the words "inertial tracking" - I will have to look into this.
Of the RF systems I have seen, most seem to require a lot of transmitters, and the reciever/sensor packages either have to be slow moving or not moving at all to gain any sort of accurracy.
The application I am driving toward, to give an idea - would be akin to motion tracking all the joints for all the players on a football team, in real-time, in an area the size of an arena football field (this *is not* the application). This is the constraint - a lot of sensors, several each attached to single "actors", moving in a very large area (both on the ground and vertically - running, jumping, etc) - and needing near-real time data sampling rates.
I live in Phoenix, Arizona - when Cox rolled out its high speed internet, and USWest rolled out its DSL - you could get from USWest television service over the phone line. There was a set-top box that plugged into the phone line, and your TV plugged into it. Their TV guide directory system was sub-par (I prefer Cox's directory over everything else I have seen) - but it was cable TV over the phone lines. I have no idea how they were doing it - whether it was like cable where they allocate different frequencies, or if it was DSL data...
I don't know if it has been mentioned, but I remember an earlier/. submission where the author discussed what he had done at his office that he designed. His budget was pretty large though - in the end, he managed to give every cubicle a door, and two windows - the walls and such were angled in such a way that one cube looked through another cube's window, but you didn't have the "over the shoulder" peep feel (at least, that is what he claimed - the overhead design plan seemed to support this). There was a lot of other innovation as well - IIRC, he was in Europe somewhere (I think it may have been one of the Scandinavian countries?)...
I have worked in both cubes and offices - the thing I love most about an office is the door and the privacy. With a cube, invariably you have people talking around you, and it can be maddenning. If you go with cubes, try to set up traffic patterns so that there isn't any areas of "easy conversation" - junctions where people naturally and spontaneously congregate to "chat" or talk about something. For those areas (bound to occur no matter what you do) - try to keep people's desks/cubes away from them, or try to make them natural meeting spots (so that people go to them, and away from others).
Lastly, try to find someway to allow people to avoid the "over the shoulder sneakup" - nothing sucks more than to feel like someone is standing over your shoulder watching you work - even if no one is there. Allow for monitors and desks to "face out", so that the employees have their backs to the wall, and nobody can sneak up on them.
Finally, allow for a lot of cable drops and plug-ins, as well as a way to organize the cables (whether in an office or a cubicle) - nothing says "unprofessional" like a rat's nest of cables going everywhere...
A friend of mine and I had a discussion recently about what was available to cheaply and reliably implement a system to track in 3 dimensions muliple sensors (50-100 sensors) over a large area (say 100 x 100 x 30 feet in volume), with an accuracy of at least 1 foot (the smaller the better - a few inches would be perfect).
We discussed RF tags, GPS, optical, ultrasonic. We discussed sensor costs ($50.00-100.00 per sensor seemed reasonable) and size (they need to be small and rugged). We discussed limiting the environment that the system would be used in to come up with a cheaper system. The system also couldn't interfere with other people outside the volume, nor did we want outside interference to be a problem. Non line-of-sight is also a priority (thus ruling out optical systems).
Thinking about it, GPS seems like the only real option - but it seems to have its own set of issues: speed is an issue (update rates aren't that fast - the more samples-per-second, the better), accuracy for civilian use is poor, and it may not work in the indoors environment we are envisioning the system being used in (which is part of the application).
It does have a pro side: Garmin makes small and cheap matchbook-sized OEM components which can send a serial stream to a microcontroller or PC via a serial port.
Can a differential GPS signal be put in the area to increase the accuracy just for the volume being measured?
Is there another solution? Because of the line-of-sight requirement, optical tracking solutions, while cheap and allowing for high-speed, large volume scanning - are not sufficient for our application.
Something else I have thought about, similar to RF tag location (which seems to have dodgy accuracy and speed), is using radio (active FM) sensors, and low-power FM transmitters placed in the four corners of the upper portion of the volume - and measuring gain to compute intersection spheres to get the position (but I doubt it would be accurate).
Can anybody tell me if such a system as needed, or technology, or white papers, etc - are available for such a system? I only need X/Y/Z coordinates, yaw/pitch/roll attitude measurements are not really needed.
It seems like large volume position tracking (with fast sampling, great accuracy, and multitudes of sensors) is something that either doesn't exist - or that would satisfy a major market. GPS seems like the only possibility - am I missing something?
Slashdot Mirror
Some get marked "classified" instantly. Some of the classified stuff may actually get downgraded (because of age or lack of relevance in the current time period). Some formerly public stuff (that at one time was classified, then made public later) has actually been made classified again. In some cases, this was wholly successful (and we will never know what cases those were), all public copies having been retrieved or destroyed. In other cases, the public has won (or been sceded to) - such as the case of the Economist and the H-Bomb plans...
Those papers that are allowed through, then have to be copied, read, blacked out (ie, redaction), then copied again. Most of the stuff isn't even on computer - it is still large warehouses of paper and tons of copy machines.
One huge, ancient, creaky and wasteful system - just like every other part of our lovely government...
Something people here seem to be wondering is how this system will compare in safety of preventing ground explosions of the shells (in the event of a misfire or other mishap).
Something that I hope a lot of you know about is that the shells used in many displays are becoming very sophisticated. For a couple of years now they have had microcontrollers and other electronics in the shells, which can be programmed to cause the shells to do various effects (almost to the point of a custom effect shell). Some of these effects allow for timed designs - if the shell goes off right, you now have an expanding circle of "pixels" - so of you may have seen happy faces and hearts and similar designs done with shells. The microcontrollers can be programmed right before the launch to know when to explode (time or altitude based). I wouldn't be surprised if they don't have RF-based (hopefully over a secure encrypted channel) detonation. Perhaps even in-flight reconfiguration?
Fireworks have recently become really high-tech, thanks to virtually throwaway low-power microcontrollers which are small and easily integratable into the shell. While none of this removes the possibility of a ground explosion, it does help lessen it (electrical ignition rather than timed fuse), and allows for more impressive effects and displays...
Spatial warping would be accomplished either by lenses or software (to "flatten" the image back out, caused by distortion of the curved surface of the projection screen).
You could probably build such a workstation for under $10,000 (the projector will be the expensive part, not to mention the custom back projection screen).
External rendering boxes are nothing new - Evans and Sutherland have been doing this for years with their high-end OpenGL rendering hardware for simulation use. I don't know what their current hardware uses (or if it is still external), but they used to use a SCSI-based bus system...
Don't confuse patriotism (ie, a questioning attitude toward leaders, wanting them to represent you, etc) with nationalism (ie, never questioning or fearing to question your leaders, etc).
What many people here in the US think is patriotism (and have been spun to as patriotism), is nothing more than pure nationalism.
Patriotism is a good thing - nationalism can easily lead down a very bad and dark road (just ask anyone over age 50 or so in Europe or the UK)...
There are basically two kinds of CAVE projector setups
1. A single, high-frequency (read that as big $$$$) projectors (120 Hz+), which use "flicker goggles" (though at these high frequencies this is rarely an issue) - like CrystalEyes glasses or something similar.
2. Dual projector systems (lower frequency projectors are cheaper) which use polarizing filters and similar glasses, each projector getting a different view from the rendering engine PC for the 3D effect.
The problem with the second system, while it can be cheaper (plus you don't have to deal with issues of wires or batteries in the glasses, just use cheaper polarized glasses - nearly throwaway), is the problem of registration - how do you get both projectors to overlay the image the same on the screen without undue distortion (keystoning) - if you place them side-by-side, you have an issue, same with on top of each other (plus there are ventilation issues, but that is another topic).
Ideally, you would want to use a prism or something to combine the sources - but this opens up other expenses (as well as light-loss issues, which will already be an issue with the polarizing filters).
Just keep it in mind as you build or consult on this system. The registration issue may not seem like much, but it can easily cause eye-strain and other issues when in use, and you will already be fighting physiological symptoms (ie, simulator sickness) just because it is a full or near-full immersion system...
The software is cheap/free, too - plenty of options there, from modded UT and Quake offerrings (among others), to Python/PyGame/OpenGL combos.
Where you will be hit is the HMD/output end. If you are willing to go with a lower resolution (640x480 - 800x600), there are plenty of offerrings on Ebay and elsewhere - you have to know whether your app will need immersion (60 degree H x 45 degree V FOV minimum), or if you need resolution (always a tradeoff). If you are looking for immersion (personally, I always prefer to be immersed - its VR, not looking down a tube!), look into a Visette 2 or Visette Pro HMD. These HMDs could be termed "arcade" or "prosumer", or low-end research HMDs - the Visette 2 HMD was used on the Virtuality 2000 series pods, and can be found used. One caveat though, it needs PAL (composite) video inputs. The Pro version takes SVGA.
Try to "try-before-you-buy", if you can (very difficult, I know). For the Visette 2, go to Vegas or a theme park and look for the Virtuality "VR Arcade" or whatever they call it, and try it out (stay away from the older Virtuality 1000 pods, the HMDs are heavy, and low res - but great FOV).
At any rate, you should be able to pick up an HMD for under $1000 if it is used (I have bought both a Visette Pro and a CyberEye CE-200M HMD for under $300 each off ebay). A new HMD like that will run from $1500-2500.00. A final option would be to build the HMD yourself - easily doable, people did it all the time back in the early 90's using handheld casio TVs.
The nice thing about the Visette 2 HMDs (off an actual Virtuality pod), is that they have Polhemus receiver coils built-in - meaning that you can easily interface them with Polhemus 6DOF tracking systems. Same with the Virtuality 2000 pod's joystick.
Tracking is where you will also run into money issues - expect to pay around $2000 for a good tracking system. If you just need head movement, though - and can live without "roll" of the head (only yaw and pitch), look into modding a GyroPoint GyroMouse for the application - simple, and cheap 2DOF head tracking. There are also a lot of simple tracking possibilities that can be homebrewed, as well - but if you want a commercial system, expect to pay some money.
Now, as far as gloves are concerned, you would probably do best to get a commercial 6DOF tracking system (put the sensor on the back of your hand or wrist), then buy some lycra gloves, sew some brass button "snaps" onto the fingertips and palm, and make a "pinch" circuit recognition system (rather than tracking finger bend - unless your app requires it). Gloves will run you an arm-and-a-leg - they are so niche (and still locked up in patent issues from the VPL patent set - it was a very broad and large patent suite that VPL had). You can spend a lot here. Roll your own, if you can (and if you aren't selling a product - most any glove that you homebrew will stomp on a number of patents). Another possibility is to hack up/apart a powerglove for the flex sensors, then sew them into/on a lighter lycra glove...
If you aren't going to want to "look around" your world, then simple shutter glasses, like they sell for game systems, can be had for cheap - and you don't even need dual monitors for it. If you want something more professional, a CrystalEyes system would be best, but be prepared to spend some cash.
Even if you go completely professional (and stick with a regular PC and free/open source VR software solutions), you can easily do this for under $10,000. If you really take your time, you can easily do it for much less (remember, homebrew VR on PCs used 386's back in the early 90's - cost for a VR setup really hasn't changed much if you homebrew all or most of it - its only when you bri
If it is coming straight down, all that mass is going to slam into the water - I wonder what kind of tidal motions that would set up, and how bad it would be for shoreline communities? I suppose it would depend on where it was situated - the further out from land, the more energy the wave will expend before it reaches land - but you wouldn't want it too far from shore, as you need to economically get people to the loading platform/dock...
Once you have the elevator, make water part of the mass, and shielding all in one go - once at the platform, it could be stored for later processing into fuel, or use it for drinking, or space-based agriculture...
Nothing is dangerous if it is respected for what it is and what it is capable of. It is only when you mix ignorance, stupidity, or willful disregard do you get "danger"...
Hell if he owns an automobile he has a ton of explosive potential at his house (big gas tank full of gasoline, plus that potential energy storage "tank" we call a battery - oh, which also vents hydrogen and other flammable gasses)...
Storage of explosives at home is a strawman argument...
I am wondering if an inversion of this could be done - compressed gasoline or kerosene (or some other flammable liquid - methonol or something), "pumped" (the pressurization of the liquid would do this - pressurize it with an air compressor or hand pump) through a solid-fuel oxidizer core (perhaps ammonia nitrate fertilizer-based?)...
Not sure if this would work - and I am not crazy nor experienced enough to try it out...
I can't imagine a quick salvo being built and fired off perfectly. During the launches I have seen, more than a few failed on the pad, many failed mid-flight. I have seen video of launches that exploded on the pad (without the help of explosive tips). Lastly, none of the rockets I saw went 60 miles - hell, none broke 20,000 feet, nor went out of the flying envelope secured for the days (pretty large volume, too).
That isn't to say that these things couldn't have been made to be missles - but the expense and expertise required to do so is huge, so huge it hasn't happenned yet, despite high-powered model rocketry being around for well over a decade (and model/experimental rocketry being around for much, much longer).
Finally, for the people that do this - it is a hobby. These are guys (most are grown adult men with maxed out credit cards or other funding) who instead of buying a motorcycle or a boat, build large and expensive rockets to fly and amaze their peers with. As a spectator, I have found it to be an incredible and exciting hobby. It tempts me to get involved in it - I just can't afford it (either monetarily or time-wise)...
Unless things have changed lately (I don't kepp up with this stuff, so I suppose they could have), retinal scanners usually require the user to look into the device, which then uses suction to "suck" the camera against the eyeball and hold it in place (very still) so that the camera can see into the eye and quickly capture an image of the retina for comparison purposes.
From what I understand, it is a very uncomfortable thing to go through, so you only see them being used in very-high security environments. There is also the issue (with any kind of eye scanner) of risk of infection (pink eye, styes, etc) to multiple users. Both of these issues, together (not to mention high cost for the scanners - though this might have come down) limit the use of the devices to mainly niche markets...
Perhaps a little vinegar?
They may be "scared shitless and completely ignorant" - but there are two types of ignorant people: stupid-ignorant people who throw their hands up in the air, and say "oh, well - nothing I can do about it" or fret over the problem, and intelligent-ignorant people who say "Damn, why is this happenning?", and then seek out sources of knowledge, using the internet, library, bookstore, friends, etc - to come up with an answer, a solution, and then learn (thus losing the ignorance of the problem) - so that they have a future more enlightened and knowlegable view of computers as a whole.
Unfortunately, most computer users fall into the stupid-ignorant category. Furthermore, it not only affects their daily computer usage patterns and "knowledge", but their entire life. These people seem incapable of using logic and reason in a manner which increases their knowledge base on any subject. These are the people who don't seem to understand that you need to change your oil and shocks on your car, or that timing belts need to be replaced (lest it breaks causing massive damage to the valves in your interference-style engine - big bucks for the machine shop). These are the people who buy brand new houses in brand new subdivisions with brand new HOA agreements (for brand new ultra-high prices) - then get angry because the HOA fines them for having grass an inch higher than it should be (one would think they would have read and understood the terms of their contract, and what they were getting into) - oh, yeah - and the house is built like a cardboard box that can have a golf ball knocked through it...
I don't pity these people - I openly laugh at them. I have tried to educate them, but the knowledge that I try to impart upon them just sails between their ears - you can damn near hear the hollow echo of the wind from their heads, as you gaze at the empty and far-away expression they wear on their faces.
Hell, even sheep look more intelligent at times...
Has this changed? I haven't been in a Best Buy in over 2 years (last time was while shopping for a freezer - ended up buying one at Lowe's)...
Now, I don't know about you (some people can stand it), but hot water (ie, hot water from your water heater for a bath, say 125 degrees F) doesn't feel good in the crotch area. This *should* be common sense. It should also be common sense that to make coffee, you need to boil it, then keep it hot (at least 125 degrees - which is still hot enough to "burn" the skin - maybe not physically as in "going to the hospital", but it can be painful) before serving it (iced cappucino notwithstanding, of course).
Now, McD's did make it very hot (180 degrees F, IIRC) - but even so, even if it was "bath water hot" - that would still have been hot enough to potentially hurt.
Common sense should tell you not to put hot liquids (ie, anything over say 115-125 degrees F) on or near your crotch, lest they spill, and at a minimum cause some pain - or worse.
This woman gambled by doing something really stupid (even if it was cold liquid - you don't want to put it there because it could either freeze the jewels, or spill, leaving a wet spot, leaving others to wonder whether you urinated on yourself - not a good social situation, right?) - and she lost big time because the coffee was extremely hot (2nd degree burns?).
Honestly, I think she and the jury screwed up - she should not have gotten any compensation. There wasn't any negligence on the part of McDonalds - they didn't spill it on her. They simply brewed the coffee (which involves using boiling water), then kept the coffee at a high temperature (but well below boiling) to keep it tasting good (well, as good as McDonalds coffee can taste - eh) - I would be willing to bet that the majority of restaurants, at the time, did this as a matter of standard cooking practice. They served it in a cup with a lid (now, if the lid was loose - which I can't remember if it was - then that could be an issue - but common sense has always told me the first thing you do at any two bit fast food joint, when you get your drink, is check the lid on it - followed by checking your order in the bag to make sure it is all there). This is all standard.
When the woman decided it was a good idea to put the coffee between her legs, knowing it was hot, without verifying the lid was on correctly - how can the producer be liable?
So nowadays, we see all sorts of disclaimers on our food: "Caution! The food you are about to eat is hot!" (no shit, like I paid for cold egg rolls), etc.
I am waiting for the day they put a warning stamping (a sticker wouldn't last), and/or color markings, on or near the tailpipe of an automobile "Caution: Tailpipe is HOT!!!" - Here's your f'ing sign, you Amerikan sheeple.
It was always "next year"-this, "next year"-that. The bad part was that we didn't see any incremental products. The best we ever got to see was a few limited applications in LCDs on laptops and other similar computer devices - but there were viable small-screen LCD displays for video use long out (on laptops) before they were being sold to consumers. We could have gotten LCD monitors (granted, on 15" or smaller, likely) long before we did - but the f'ing corps had to make every last penny off of CRT's...
In the case of private manned spaceflight - it wasn't really a case of who was going to be able to do it, but who had the balls to try. Furthermore, we (the public) have been able to see the incremental advances necessary to get where we are today in this field - much of the tech behind Rutan's ship (mainly the engine - NOX hybrids) has been available to high-power rocket enthusiasts for a few years, at least.
McDonnell-Douglas, or any of the other large, private satellite launch platform companies - could have easily (still can) sent a man into *orbit* atop one of their launch vehicles - the rockets are more than capable, they just don't have the balls (that, or they can't get the insurance for a reasonable price) to do it.
Maybe now with Rutan's first success, we will see these companies actually trying something with the tech they have.
But for all of this other technology - much of it is either vapor, or they are milking every last drop of profit out of the old technology before they release the new stuff...
What you basically want is the rear half of a motorcycle, and the front half of a lightweight, rear-wheel and engine car - an old VW bug would probably be perfect, but a Toyota MR2, a Fiero, or a Honda Del Sol would work well, too (and be lighter weight).
All of these can easily be found in junk yards, so find a running (but with front end damage) used motorcycle, with a larger engine (something to push the extra weight. Cut the front off the car, and with a lot of welding, cutting, torch-work, and some steel...
In the end, you can have what you want - basically, it is the reverse of the 3-wheel motor-trikes you see every now and then (which use the rear of a VW bug most of the time)...
Unfortunately, the application has to be real-time, or near real-time sampling rates, for a large number of sensors. Post-processing the data is not an option.
Of the RF systems I have seen, most seem to require a lot of transmitters, and the reciever/sensor packages either have to be slow moving or not moving at all to gain any sort of accurracy.
The application I am driving toward, to give an idea - would be akin to motion tracking all the joints for all the players on a football team, in real-time, in an area the size of an arena football field (this *is not* the application). This is the constraint - a lot of sensors, several each attached to single "actors", moving in a very large area (both on the ground and vertically - running, jumping, etc) - and needing near-real time data sampling rates.
I am not even sure such devices exist.
I live in Phoenix, Arizona - when Cox rolled out its high speed internet, and USWest rolled out its DSL - you could get from USWest television service over the phone line. There was a set-top box that plugged into the phone line, and your TV plugged into it. Their TV guide directory system was sub-par (I prefer Cox's directory over everything else I have seen) - but it was cable TV over the phone lines. I have no idea how they were doing it - whether it was like cable where they allocate different frequencies, or if it was DSL data...
I have worked in both cubes and offices - the thing I love most about an office is the door and the privacy. With a cube, invariably you have people talking around you, and it can be maddenning. If you go with cubes, try to set up traffic patterns so that there isn't any areas of "easy conversation" - junctions where people naturally and spontaneously congregate to "chat" or talk about something. For those areas (bound to occur no matter what you do) - try to keep people's desks/cubes away from them, or try to make them natural meeting spots (so that people go to them, and away from others).
Lastly, try to find someway to allow people to avoid the "over the shoulder sneakup" - nothing sucks more than to feel like someone is standing over your shoulder watching you work - even if no one is there. Allow for monitors and desks to "face out", so that the employees have their backs to the wall, and nobody can sneak up on them.
Finally, allow for a lot of cable drops and plug-ins, as well as a way to organize the cables (whether in an office or a cubicle) - nothing says "unprofessional" like a rat's nest of cables going everywhere...
We discussed RF tags, GPS, optical, ultrasonic. We discussed sensor costs ($50.00-100.00 per sensor seemed reasonable) and size (they need to be small and rugged). We discussed limiting the environment that the system would be used in to come up with a cheaper system. The system also couldn't interfere with other people outside the volume, nor did we want outside interference to be a problem. Non line-of-sight is also a priority (thus ruling out optical systems).
Thinking about it, GPS seems like the only real option - but it seems to have its own set of issues: speed is an issue (update rates aren't that fast - the more samples-per-second, the better), accuracy for civilian use is poor, and it may not work in the indoors environment we are envisioning the system being used in (which is part of the application).
It does have a pro side: Garmin makes small and cheap matchbook-sized OEM components which can send a serial stream to a microcontroller or PC via a serial port.
Can a differential GPS signal be put in the area to increase the accuracy just for the volume being measured?
Is there another solution? Because of the line-of-sight requirement, optical tracking solutions, while cheap and allowing for high-speed, large volume scanning - are not sufficient for our application.
Something else I have thought about, similar to RF tag location (which seems to have dodgy accuracy and speed), is using radio (active FM) sensors, and low-power FM transmitters placed in the four corners of the upper portion of the volume - and measuring gain to compute intersection spheres to get the position (but I doubt it would be accurate).
Can anybody tell me if such a system as needed, or technology, or white papers, etc - are available for such a system? I only need X/Y/Z coordinates, yaw/pitch/roll attitude measurements are not really needed.
It seems like large volume position tracking (with fast sampling, great accuracy, and multitudes of sensors) is something that either doesn't exist - or that would satisfy a major market. GPS seems like the only possibility - am I missing something?