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I for one am very happy to see this technology advancing. It's not gonna take much intelligence to make an autonomous driver better than most human drivers.

The benefits of having cars that drive themselves will be enormous. First, these cars can be programmed to drive in a manner that conserves gasoline (e.g., no jack-rabbit starts, limit speeds to 55 mph, time their accelerations between stoplights so they don't have to come to a complete stop at every one). Second, cars that drive themselves in a rational manner -- instead of the emotional, irrational manner that people drive them -- can significantly reduce traffic jams. There is an insightful analysis of traffic jams at this page which explains that jams are larely the result of people not letting other people merge into their lane coupled with the relatively-slow reaction time of humans. Cars that can synchronize their motion in relation to nearby traffic could make traffic jams a thing of the past.

Not to mention that if the car drives itself, I can read slashdot on the commute home (or watch Natalie Portman movies).

GMD

A Van De Graaf generator is basically a band of insulating material being rotated in a tower with some means of transferring a charge to it. There are relatively cheap desktop and home models that'll produce nearly half a million volts. Schools use such devices all the time, so if the fireman hasn't seem a voltage that high, he skipped classes.

Having said that, early atom-smashers used Van De Graaf generators only capable of producing five million or so volts. It seems reasonable to suspect something will burn before it is blasted out of existence. So, somewhere between 400,000 volts and 5,000,000 volts, you might be able to ignite something.

However, here we get a problem. You can't just carry around half a million volts and not notice it. Your hair tends to stand on end, for a start. ANYTHING metal - even a doorknob - will cause a discharge to occur. Getting into his car certainly would have - even if the car were carbin-fiber, the key would be metal and the distance short enough for an arc to occur.

There's also the problem of where you lodge a charge that great. A capacitor is basically two electrostatic devices with an insulator between them. In this case, the insulator would be the shoes, and the electrostatic device the person. I'll assume there are enough nails holding the carpet down to act as the other electrostatic device.

But what is the capacitance of a person? The figure I've been able to get with a Google search is an average of 204 pF with a typical range of 95 to 398 pF. (It varies according to height and weight, so a seven-foot sumo wrestler might have a higher capacitance than this range shows.)

In other words, not really what you'd need to carry half a million volts around. The jacket would have carried more, but unless it was made of Tantallum or some other material with very high capacitance, I doubt you'd be able to store enough charge to start setting things on fire.

In other words, there is nothing credible about the story. The voltages are abnormally low for a static device and way too low to actually do any fire damage, there's nowhere a higher charge could have been stored and there would have been too many points at which positively violent arcing would have occurred if it had been stored.

taxing Beethoven would level the playing field for young/contemporary "classical" composers who have to compete with the huge body of royalty-free music.

Taxing the wheel would certainly level the playing field for young inventors who have to compete with the huge body of royalty-free inventions.

If companies had to pay a hefty tax for using ordinary wheels then they would have a huge incentive to pay inventors to create innovative alternatives that would be cheaper than paying the tax. Just imagine all of the new innovation in reuleaux triangle wheels and cuboid wheels and even perfectly square wheels!

We should tax the entire public domain! Why should we let people get away with using old stuff for free? Better to stimulate the economy by forcing them to hire someone to make something new. People using old free stuff are nothing but a bunch of theives, dragging down our economy.

Chuckle.

-

For example
Bert Hickman's coin shrinking
Thaltech's capacitor experiments
Sam Barros's Power Labs page
Bill Beaty's webpage
and many others...

Don't forget hand-drawn holograms, as described by Bill Beaty!

Traffic Waves.

There is a very good, if somewhat casual, study out there that says that the BEST way to remove congenstion is to always drive slow enough to keep a goodly sized (several vehicle length) hole ahead of you.

I believe the "study" you remember may be Traffic Waves by William Beaty. I originally found this site via somebody else's sig a while back. I spent a good half hour digging it up today so others could read it.

I'm no more qualified to understand traffic than you or he is, but I read it extensively when I stumbled on it and it makes a lot of sense to me. It'd be really nice if a professional traffic engineer could chime in and say how accurate this all is.

Scientific American's Amateur Scientist has always had interesting things to make. The older columns (from before the age of lawsuits) featured more exciting things such a a 6-foot homemade rocket, atom smasher, and 20 W CO2 laser.

It really isn't immaterial. Treating traffic flow as a fluid dynamics problem, it becomes apparent that reducing the flow of traffic will untangle traffic snarls, improving the flow. Basically, the more cars try to jam into a bottleneck, the slower traffic becomes, the slower it becomes, the worse the bottleneck becomes, untill traffic comes to a standstill with people still trying to jam themselves in. Sort of like early in rush hour, traffic flow is generally very heavy, but quick. Somebody having to hit their brakes, due to tailgating, being cut off, or not let into a lane causes small ripples of congestion which add up to the point that traffic flow comes to a standstill or at least a major slowdown. Appropriately reducing traffic flow at key points could eliminate or at least reduce congestion, without the costs (financial, social and environmental) of adding more lanes of concrete.

Although teaching people how to drive and to actually use lanes appropriately would probably do more than any technological gizmo that we could create at this point.

If you're talking about seeing heat, that's far spectrum infared. Our eyes can already see bright near spectrum infared, just as we can hear loud subsonics. If you filter out visible light on a bright, sunny day, you can see some infared. Check out http://www.amasci.com/amateur/irgoggl.html for a cheap interesting experiment regarding this. I tried it with mild success, I need to play around with it a bit more.

But from what I can tell from the article, anything you can get to show up on some kind of display could probably be outputted to the bionic eyes. Heat vision would just require the same bulky and expensive equipment, just minus the screen. Most of the mass of heat vision infrared goggles comes from cooling the sensor so you can see things other than just the heat from the sensor itself at room temperature.

The false colors in present day heat vision equipment may not be necessary. It would be interesting to see how the brain processed those signals.

This is offtopic, but I hate Traffic, go here and prevent it for the good of the nation. http://amasci.com/amateur/traffic/traffic1.html

That's bizarre! I've never heard of this guy, nor seen his site, but there's the death squad in all its glory! I wonder if this has been featured on Halfbakery too?

I like the Duck-plunge Mechanical Fountain, that could be a neat waterpark ride.

> Has anyone else had this idea too, or am I the only weirdo around here?
Yes, Bill Beaty did years ago. I imagine you took the idea from him. Give some credit where it's due.

"Kindergarten Solar-powered Death Squad
Take a large crowd of children out into the sunshine and give each one a 20cm square mirror. Show them how to aim all of their little spots of sunlight at the same distant object, then stand back and see what they do. Better yet, run away. "
- http://www.amasci.com/hoax.html

I read an article about http://www.amasci.com/amateur/mirror.htmlthis solar array quite a while ago, I thought it had been posted hear. 112 mirrors doesn't really sound like a lot.. if you covered a 4 by 8 sheet of plywood with 1 inch mirrors, you'd be able to get 4608 mirrors in your array, not allowing for clearance. if you use the same number and make the mirros 3/4 inch, you would end up with a target spot around that size at 4608 times the power of the sun. I think that would do some considerable damage.

"Kindergarten Solar-powered Death Squad

Take a large crowd of children out into the sunshine and give each one a 20cm square mirror. Show them how to aim all of their little spots of sunlight at the same distant object, then stand back and see what they do. Better yet, run away.

FAST!"

And another one here...

Anyone remember that PR nightmare a couple years back when people found out that using the IR (marketed as a nightvision) system on a certain Sony handheld cam would allow people to see through thin layers of clothing? A Google search for Sony x ray should give the results for anyone who is interested. And on the topic of cheap IR gear, http://www.amasci.com/amateur/irgoggl.html. It's effectively the same thing as this story but it's about what happens if you just stick the filter on a pair of goggles and use them during bright sunlight.

--
Free iPod? Try a free Mac Mini
Or a free Nintendo DS, GC, PS2, Xbox
Wired article as proof

Electrical chips run far below 1% of c.

Yeah, the flow of electrons in wire is extremely slow, but the work is really done by the electrical field generated, so that as one electron is pushed into the wire, it "pushes" the sea of electrons forward so that an electron at the other end of the wire is shifted forward. This "shift" occurs pretty close to c. I

I would say:
- Practice your grammar
- Drill yourself on spelling
- Love W3C's website
- Study this list
- Study user interfaces, particularly the bad ones (like most corporate websites)
- Arm yourself with multiple versions of multiple browsers
- Understand all the Meta tags that you can

The US has many more roads than Japan has, over a wider dispersed area. The investment necessary to do such a thing would be impossible to fathom, not to mention the technical challenge of processing all that data. We'll have to be satisfied with other solutions in the meantime.

Driving is a co-operative thing. Traffic has properties of fluid and properties of dynamic packets on a switched network, each with discrete start and end points. By not following a set of pre-ordained rules that all fellow traffic drivers share, you are fucking shit up.

I hope you learn how to drive co-operatively with others thanks to technology like this, because fucktards like you cause congestion and impede the normal flow of traffic.

See also: traffic waves.

The cheapest way to make a hologram: http://www.amasci.com/amateur/holo1.html

Actually, you can do some preatty neat stuff with microwave oven parts... poke around billb's website for more info.

Wouldn't the opposite approach make more sense? Make the cars go faster, but leave large gaps between the cars. Not only would that leave extra space like this guy and then the cars would have an easier time doing any maneuvers they need.

Excerpted from the link below:

Have you ever been driving on an interstate highway when traffic suddenly slows to a crawl? You inch along for many minutes while waiting to see the accident which must have caused the jam. At the same time you also curse the "rubberneckers" who are causing the whole problem. But then all the cars ahead of you take off at high speed. The jam is over, but no accident, no police cars, nothing. WHAT THE HECK WAS THAT! A traffic jam with no cause? In the rear-view mirror you see all the poor saps behind you still stuck in the jam. But why? If all those people could just speed up at the same time, the whole traffic jam would evaporate. Why don't they ever do that? What caused the mysterious slowdown in the first place?

After experiencing many of these "invisible accidents", I came up with the following explanation. To best understand this, imagine that you look down on traffic from an aerial view point. Pretend you're in a Traffic Reporter's helicopter looking downwards.

Traffic Waves

You don't need autonomous vehicles to combat traffic jams.

The really fun stuff is hand-drawn, and all you need is a compass (with two points) and a shiny but scratchable surface. Oh, and a bit of time.

Hand Drawn Holograms.

-Billy

instructions here.

don't forget the classics!

I will be eager to see this magazine! I was very bummed about the demise of the "Amateur Scientist" column from Scientific American. You can get that wonderful column on a CD (yes, that has my ref id in it) or read recent articles online. The old articles are the best--how to construct electron/proton accelerators & the like.

As some of you know Tesla already envisioned a realistic nearly perfect method for harnessing energy from Earth's atmosphere. But that would have destroyed the monopoly of electrical companies and was thus never allowed to come into existence. Cold fusion research was not as promising, but it was nipped in the bud for the very same reason. Progress standing in the way of the profit of a select few.

Free power? Unheard of. Free software? Unheard - wait a minute!

"Lift occurs when you have a high-velocity fluid moving above an object while a lower velocity fluid is moving below the object."

No, lift occurs when air pushes something up. From the sounds of things, it looks like you're hung up on the classic "bad science" definition of lift. Wikipedia has an article here that explains lift in a way that doesn't give Bernoulli more credit than he's due.

"In the case of a roof in a hurricane, there can be over 200kph winds above with 0kph below resulting in tremendous lift."

Not unless the house was shaped like an upside-down pyramid. Newton must always be obeyed, so unless there's some angled surface for air molecules to smack into and be deflected donward off of, there's nothing pushing the building up. So long as the building is relatively sealed, there's nothing pushing up on the roof of the house (because of the size of a hurricane, static air pressure inside the house is going to be about the same as the static air pressure outside of the house).

"Wind pressure" only happens to surfaces that are tangetial to the wind direction (i. e. has air molecules smacking against it).

"If air was allowed through the house at the same speed (assuming an airflow parallel to the ground), the negative-lift generated inside the house would somewhat offset the lift occurring outside (a good thing)."

Only if the airflow through your house was perfectly laminar, and it would be anything but. Instead, the air molecules that flow through your home will be smacking off of everything and anything, especially interior walls. As they rebound, a good deal of them will be deflected upwards, towards the roof, pushing it up.

"I believe in some places in the Caribbean, they open the front and back doors wide open to help keep the roof from blowing off."

Unless those people have nothing in their homes that would restrict airflow (which might be possible, considering poverty levels in the region), the only people I could see giving that advice would be contractors.

Now, moving on to your other comment...

Bill Beaty investigated how to avoid traffic jams by recognizing the intermediate state of synchronized flow and undoing the damage six years ago. Apparently, a traffic jam can be stopped, even once started, by a single car.

Traffic Waves

See also this site.

Have you ever been driving on an interstate highway when traffic suddenly slows to a crawl? You inch along for many minutes while waiting to see the accident which must have caused the jam. At the same time you also curse the "rubberneckers" who are causing the whole problem. But then all the cars ahead of you take off at high speed. The jam is over, but no accident, no police cars, nothing. WHAT THE HECK WAS THAT! A traffic jam with no cause? In the rear-view mirror you see all the poor saps behind you still stuck in the jam. But why? If all those people could just speed up at the same time, the whole traffic jam would evaporate. Why don't they ever do that? What caused the mysterious slowdown in the first place?

In 1998 William Beasley posted a paper on Traffic Waves in Seattle, subtitled "SOMETIMES ONE DRIVER CAN VASTLY IMPROVE TRAFFIC".

The site has great animations and excellent explanations of the impact of different drivers actions on the overall flow.

Worth a look: Traffic Waves

to this page which was linked on slashdot a while back.

I was just reading about something like this just last night.
I'll bet it ends up working on the same principle that Bill Beatty is talking about when he got to thinking about why it is that an atom can absorb light so readily even though the size of the atom is such a small fraction of the wavelength.
Relevent articles:
Energy sucking antenna
On the Possibility That Electromagnetic Radiation Lacks Quanta of Any Kind
Nearfield coupling and tuned circuits

I was just reading about something like this just last night.
I'll bet it ends up working on the same principle that Bill Beatty is talking about when he got to thinking about why it is that an atom can absorb light so readily even though the size of the atom is such a small fraction of the wavelength.
Relevent articles:
Energy sucking antenna
On the Possibility That Electromagnetic Radiation Lacks Quanta of Any Kind
Nearfield coupling and tuned circuits

I was just reading about something like this just last night.
I'll bet it ends up working on the same principle that Bill Beatty is talking about when he got to thinking about why it is that an atom can absorb light so readily even though the size of the atom is such a small fraction of the wavelength.
Relevent articles:
Energy sucking antenna
On the Possibility That Electromagnetic Radiation Lacks Quanta of Any Kind
Nearfield coupling and tuned circuits

I was just reading about something like this just last night.
I'll bet it ends up working on the same principle that Bill Beatty is talking about when he got to thinking about why it is that an atom can absorb light so readily even though the size of the atom is such a small fraction of the wavelength.
Relevent articles:
Energy sucking antenna
On the Possibility That Electromagnetic Radiation Lacks Quanta of Any Kind
Nearfield coupling and tuned circuits

You can do something about it, if you care to. The biggest causes of stop and go traffic jams on freways are onramps and offramps, and the "gotta win" mindset that doesn't let people merge into traffic flow or change over to exit flow. Start leaving a few car lengths of space ahead of you when you drive on freeways. By doing this, you're giving people room to merge in and out, and you're also giving the wave time to break up before you reach it. I've gotten into the habit of doing this, and wouldn't you know it that if I leave enough space ahead of me, traffic jams just seem to break up right as I approach. Most times, I don't even have to brake as I come up to them.

Yes, people will move into the gap you're leaving. That's the whole point. Most people in traffic jams don't try to change lanes, so they won't know or care that you have a few car lengths of space ahead of you. For the people that do care, they're free to move into that space (when they do, just open up another car length of space). You don't even have to go slow to do this. A few miles per hour slower than the average speed will easily open up a nice gap you can carry to the next traffic jam. As the traffic clears, you can speed up. If you do find that you misjudged your leading distance and end up having to slow or even stop, just pause a moment before starting again. That will open up a space in front of you.

None of this would be necessary if people actually had adequate driver training, but sadly that's not the case in the States. Driving is consider a "right" rather than a privilege, and driver training suffers because of that (Joe Sixpack or Jane Soccermom will throw fits if they fail a driving test and have to give up their license).

I've been trying a similar experiment but all tests seem to end at the fifth hop.

Here are some good things to read:

Traffic Patterns and How To Erase Traffic Jams

Traffic Psychology

Traffic jam analysis. FAQ.

Traffic jam analysis. FAQ.

This guy put a lot of thought into the "leaving a buffer" theory. His links page has some really cool links.

You are the traffic jam, but you don't have to be.

William Beaty studies traffic for a hobby. He created some "traffic experiments" and describes his results and theories in "TRAFFIC WAVES: SOMETIMES ONE DRIVER CAN VASTLY IMPROVE TRAFFIC". It's pretty interesting stuff.

The "intelligent roadway" concept sounds all gee-whiz and cool, but the fact still remains that it's we, the drivers, who are responsible for both the volume and the density of traffic. Our being on the roads in the first place generates the volume, and our need to get "there" first generates the density.

Someone posted a link to this site about how one driver can singlehandedly eliminate traffic waves simply by not driving like a nut. I've tried it, and it's not difficult, but I can't imagine convincing my wife to let a gap open up in front of her... there's something in human nature that rebels at the thought of someone else getting ahead of you in line.

My prediction: If these devices and systems lead to more efficient roads, then there will simply be more people on the roads. The end result will be *worse* congestion than before. That's why building new expressways is so futile -- you just can't build your way out of gridlock. [Insert mass transit rant here]

Put some dangly wires from an electrostatic generator to the ground, and charge the car body to a few thousand volts. Set it up so it's only charged when the vehicle is not in park. Remember to put it in park before you exit.

I'm sure there's an easy way to turn all four wheels into a VandeGraaff generator

Of course, I'm a cyclist, so if I find your car has an abnormally large charge, I'll help it discharge by removing the gas cap, dropping a wire inside, and allowing it to slowly fall out of the car through wind resistance until it contacts ground.

-Adam

The flow of traffic is pretty neat. With "psychopathic tail-gaiting rigs, pickups, and SUVs" I just brake slam them until they go around. If they don't wish to drive properly behind me and give proper following distance (3 seconds), I don't want them behind me. If they haven't learned the lesson after 2 flashes + 1 really good slam (which usually has them swerving out of the way), I will stop the car until they pass me.

You don't have to play by their rules. Make your own up, as long as they match the posted speed limits (providing there aren't any extenuating circumstances). Keep your gates open, and you'll have about 4 choices of direction to go with your car should there be an emergency driving situation.