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Autonomous Race Cars
Octothorp writes: "Though not as complicated as the underwater
vehicles. There is an annual competition sponsored by National Semiconductors to build an autonomous race car. They move along pretty well too, at almost 9 ft/s. More technical information on how they are built is available on a Berkeley page, and there's a video of the winning run for 2002."
Aires, the other trolls are starting to tire of your self-delusional and selfish demeanor. You are not the one to lead the revolution. There is not even a revolution. In the coming days you should stray from your "blind and barbarous" charges into the frontlines of battle. Balance your self-aggrandizing trolls with humility or brotherhood. You blazed a trail through the e-wilderness but now you have blitzed your penis into a brick wall. Start looking for that balance with the universe and its inhabitants which you lack, lest you blindly and bluntly charge your erect manhood into ESR's sweaty, pulsing, and filthy anus. And you don't want to do that, do you?
Taurus
You provide foundation and structure to trolldom. If there be an Empire, then let its roots be your works. Yours is the first earthly manifestation of our combined and unified beauty, but now you have a choice. You can either lazily roam the fertile pastures and suck the sweet honey of victory, or you can help build Babel to the heavens. Beware, the former might lead to you sucking the semen from Taco's cock, while the latter, although lifting you from your sacred footings and unnerving yourself, may prove to be the wisest choice.
Gemini
You have many talents. Your trolls can be beautifully written, exhibiting your natural communication talents. Your mind is quick and flighty. Have you ever realized the variety of your pieces? One night you might write a homosexual expose on Linux faggotry, while the next day it is a craftily written legitimate troll. Your dual nature puzzles most and maybe even yourself. Some might not even see it outright. De Broglie contends that all matter is a wave on some level. Are you a wave, wayward Gemini? Another example is that you are a troll but you revel in using open source programs. You hide yourself well. You are a whore in most ways. And as a whore you will never be fulfilled. You may have had your fun about a week ago, but now it is not your time. It will be a while before you pull yourself back together again. But stick around, the dregs take entertainment in your plights and facetious ways.
Cancer
Remember that time you once tried to troll? Remember when everyone laughed at your pitiful attempts? Remember how you withdrew immediately and started to masturbate wildly to Hentai? Remember how once you came the neurotransmitters immediately pulsed through your being and took you to a pleasant place? The lesson here is that you are a pussy-mama and have no trolling talents. Masturbation is not a talent, fool, and you will never have your love be accepted in trolldom, or the world for that matter.
Leo
You know those days when no one seems to be trolling? Well Leo, you are our light in those dark days. You carry the torch, albeit in a conceited and self-centered way, but nonetheless you keep the Path alive. The shadow has yet to hold us sway. Don't get to full off yourself, because while you can keep a warm castle for us, you can't build us an Empire. Know your limitations sir, and also take care not to trample over the visionaries that can take you to the Next Level.
Virgo
You trolling style reeks of prudishness. To spice your life, I recommend throwing in some good bathroom humor or homosexuality into your writings. Your endless crapflooding, although detailed and nonsensical, lacks something special. You are a machine, a practical worker for the cause. You can best manifest your greatness when you are working for someone else. You should find a good Gemini (yeah I know that's an oxymoron), Libra, or Aquarius to give you inspiration and work. You need some mental stimulation right now. Actually, you could use any stimulation now, and for that, find a Libra.
Libra
Much like your cardinal counterpart Aires, you are a pioneer. But unlike Aires, your talent begins in the mind, inciting thousands of blood-thirsty trolls to rally to the cause. You lead is bond, and your bond is beauty. But did I mention you're a fake, arrogant bastard. Your superficial way can't last. Also, did you ever wonder why you rarely troll? Well, I'll tell you. You're an indecisive bastard. You start a story but then can't make up your mind over some unimportant detail. Becoming frustrated, you start jerking off to the homosexual undertones contained in your trolls. This is a mistake. Harness and channel your energy of creativity and destruction, and in the balancing of the two you might find success.
Scorpio
You are the true master of the art of covert trolling. Under the innocent guise of a harmless introvert lies a cold calculating killer brooding for the taste of blood and seminal fluids. You manipulate, scheme, lie, and sleep your way to the top. You could be a star in the sky, but you usually end up bound up in your own web of deceit. Sometimes you unconsciously look forward and plot this conclusion. In the depths of your sick twisted hell lies the key to transformation. The phoenix is birthed in the abyss, only to catch ablaze and fly soaring to the heavens. This probably won't happen to you though.
Sagittarius
You have the ability to show us "The True Path", but you would rather drink yourself to oblivion with a bunch of forest nymphs. Honestly, who here wouldn't do that? I have a desire to party with the forest nymphs tonight. Sag, let us hang out, drink much stout and wine, and fornicate with some nymphs. Fuck trolling, my carnal nature calls.
Capricorn
Always trying, always failing, always overcoming. Are you part of the allied forces, or do you contribute to the vile structure that threatens us all? Nobody recognizes your struggles because you manage to write in an earthy and uninspired monotone. What does this mean? Well, I don't know exactly what it means but I do know that you're a homosexual.
Aquarius
We all have problems, but you, Aquarius, have problems that affect us all. You fancy yourself a leader. Why? We never asked for you to bare the water to our thirsty lips. We never asked you to refine the Troll Empire into your own sick sadistic world. Once outcasted among "proper" trolls, some sick spirit from within told you, "If you build it, they will cum." Fuck those talentless bastards. The structure is now built, and the talents are ready to be poured. It is your duty to pour your metaphorical homosexual semen all over trolldom, and the world. Do not falter, for the revolution looms, and the sun will rise yet.
Pisces
Oh, what an old soul you must be. In some ways you are the flowing talent that Aquarius bares. This is doubtful though, as your inner water is probably stagnant and swarming with mosquitoes. You embody the best of the of the Zodiac. Don't get to full of yourself, because you also embody the worst. That is the key to your constant failures. You should get very angry right now and create a storm with the raging sewage inside of you. Pound trolldom from the heavens with your bile, and then cry. You may feel that no one understands you, and hell, you're probably right. That doesn't matter now, because the world needs your "talents" right now.
have you ever farted into a pillow to concentrate the stench, then put it to your nose quick enough to smell it? I have. It's strangely addictive. --fuckforce lambroghini
"someone should make a hot air balloon that is shaped like a giant vagina". --Bill Clinton
ha ha
first post bitch!!!!
ac rulez!!!
The underwater vehicle is probably a lot more forgiving in terms of control loop stability. The water gives some damping.
Engineering is the art of compromise.
All hippies must die.
You waste my air to get high-
Don't ask why, Just die.
Are hard to understand without both a subject and a verb. Though not as complicated as the underwater vehicles.
Slashdot is jumping the shark. I'm just driving the boat.
I recall an experiment done in California a few months back whereby cars automatically drive themselves on a stretch of a highway equipped with magnetic strips down the centre of the lane.
Since public transport seems to be out of the question for medium-distance transportation in the States (witness Amtrak's plight - and CoachUSA's financial gymnastics of late) automated private transport might fill the gap - provided price can be brought down.
It is really interesting to see what comes out of this. Certainly more applicable in the near future than football-playing robots - or this terrible series in the UK with robots battling each other, armed with saws, hammers and whatnot contraptions..
Curious,
Michel
Fedora Project Contribut
Anything from the Democratic People's Republic of
Berkeley is obviously communist. The only way these cars would be any good at anything is if they went fast enough to launch themselves into orbit and they took all those fucktard hippies with them.
I thought I was going crazy and this story was a repost! Then I saw in older stories an autonomous under-water vehicle story.
haha, I must be retarded. Damn college rots your brain!
http://www.freepokerchipset.info
This article has links to Berkeley, which as everyone knows is full with stinking hippies. We all want them to die, so this should be either +5 Insightful or +5 Informative, although the turdburglar moderators will probably botch this just like they always do, the group think monkey touching vaginas.
Wow! That's almost as fast as I walk! Those race cars must really be zipping along!
I read fps as frames per second. My first thought was they need a Geforce4 to go faster.
Here is my entry. =)
There is no relationship between these popped tarts and any manner of pretzels. :)
The biggest reason why Americans need to protect their right to bear arms is so anti-gun activists can be contained.
Give me a beer or die!
I love you muah!!
ajfadlafa aldsjfa lkjoiujdas!! That was superduper 1337 speke for IF I EVER MEET YOU I'LL KICK YOUR ASS!!
The goatse guy! We can't get enough of him around here, huh? I mean, really, could he *be* any more *that guy*?
Oh yeah, don't touch any special taco snottings. Or something like that.
What is it with this site and 16 year old political extremists? The world should be thankful that these assclowns waste all their time venting here and on other sites and never amount to anything in the real world.
Hey you've been a great audience, be sure to tip your local ISP PEACE I'M OUTTA HERE!!!
Neodux.com here's my site
You forgot slow.
To paraphrase horribly:
Take Amtrak... please!
.sig last updated Jan. 14, 2000
That was soooooo funy lololol. Please keep up teh good wrk.
Just to clarify for those who made the same initial assumption I did.
------------------------
Jack not name, jack job!
but at a much lower speed Movit Line Tracker
These robots were all the rage back in the late 80's.
Personally, I'd rather have RC helicopters. Yes, I know their batteries wouldn't last long... but in an office environment, tiny cars aren't going to get very far, given the amount of clutter which would obstruct them. Helicopters, on the other hand, could fly over cubicle walls to attack people...
Linking to a video file from the frontpage of /.?
Wowzers! Methinks flaming shards of this server will be moving - autonomously - at 9 ft/sec very shortly...
[/bad joke]
The annual Mobot competition at Carnegie Mellon seems a lot like this except the robots need to be able to stay on course that also has downhill slopes along it.
My tank from the 1998 competition woulda worked fine except for endianess problems between my roommates and I.
Sipping on Jolt and Dew. Laid back. With my mind of my cubicle and my cubicle on my mind.
The key to this particular competition seems to be the size and weight limits on the cars. This is a contest for little RC-style cars. The technology exists to go much faster, but not in this form factor.
Surprise surprise, the site is dead now...
It would be interesting to take one those cars (with the electronics still on for weight fairness etc), install some RC gear, and see who's faster.
I suspect that the human would still be the better driver/faster at the moment. Also, a human driver can navigate traffic. These guys look like they might have a hard time in a race with other cars ;)
this might give me the skills to leave the B-mains and hit the A-mains. Assuming they let me tape their ozite carpet. :p
It is a good thing that speed, accuracy and conserving energy are the main products sought of this competition although it would really be fun to watch these cars in motion in real life.
I vote for sponsored demonstrations of these products at Motor Racing events. Normal RC Racing always attracts a very large crowd at any event I have been too! =)
Pixels keep you awake!
This reminds me of a game where you would program little triagles to fly around a small 2 dimensional arena and try to blow each other up. I never really got into it but my friends said it was really fun. Anyone know what this is/was? It was pretty technical, not like a dumbed down programming thing like the windows version of MindStorms.
Anyway: to relate to the story: I would think coding the AI would be a LOT harder than building the cars.
We have autonomous internet access, autonomous electronic mail, and autonomous peer to peer file transfers. There's no evidence that this autonymity has been used for anything other than criminal activity. I can only imagine for what sort of nefarious purposes autonomous race cars would be used.
Call (206) 338-5780 COLLECT for information about a genuine BA, BS, MA, MS, MBA, or Ph.D.
really, 9fps = ~6mph = 10min/mile, a speed that will have you near the middle of the pack at many large road races.
"I'll have a Guinness, no wait, make that a Coors Light" -Grad student I work with, who shall remain anonymous...
Hey, stop picking on him, he brings us nice stories even if they arent gramatically accurate. :P
Pixels keep you awake!
They race one at a time...
I do think an automated car would have a very hard time in traffic though, and THAT would be a cool competition.
"I'll have a Guinness, no wait, make that a Coors Light" -Grad student I work with, who shall remain anonymous...
They make many RC helocopters, almost all of them run on small internal combustion engines, for reasons of both battery life and weight
"I'll have a Guinness, no wait, make that a Coors Light" -Grad student I work with, who shall remain anonymous...
There are 5280 ft in a mile, 3600 seconds in an hour *9 = 32400 FPH /5280 = 6.136...MPH
Why even post iit in FPS when you know almost every person that reads it will have to do the math, why don't you just give it in nanometers per light year and let us go from there?
Saying Java is nice because it works on all OS's is like saying that anal sex is nice because it works on all genders.
nanometers per year* !
I've always said that a robot could kick the SHIT out of a human at nascar. After all, how complex is 10: GO FAST 20: TURN LEFT? I bet that in five years, we'll have robots (read a bungee cord and a brick) trouncing humans at nascar. Naturally, it'll probably take the application of the AI in Gran Tourismo (ever see that asshole wreck? NO) to get robot cars to do Real Racing (grand touring, gran prix and rally). I say we leave the nas/indy car crap to the machines and go outside and play.
Why is it when I hit ^R that ZSH calls me a cocksucker?
Do you really have to be SO picky about accuracy of the post? It doesnt take a genius to work out how fast it is in real life. At least fix the error by saying its about twice the speed a normal person walks at.
If you want to be a critic do it constructively.
Pixels keep you awake!
It's my opinion that autopilot for your car is an inevitable development. It will become the only way to keep highways scaling. Adding more lanes to add capacity works to a point, but doesn't work forever. I don't think it's feasable to expect a human to navigate a twenty or thirty lane highway. And the density of traffic which an existing highway can carry is limited by the poor driving ability of humans.
I think eventually high-capacity highways will require the use of an autopilot. Doing so would allow the cars to be run with inter-car gaps which would be suicidal with a human behind the wheel. Most stop-n-go situations are due to bad planning on the part of drivers. They speed up too much when traffic clears ahead, zoom up on the cars in front, and then have to slow down to avoid an accident. This type of driving creates waves of congestion which travel backwards down the highway, and is due entirely to poor coordination among drivers. But there is no reason that under computer control rush hour can't cruise along at 60 miles an hour with a car length or less between cars. I bet you could easily triple the maximum capacity of a highway, not to mention getting everybody to their destination faster and with better fuel economy to boot. The R&D will be expensive, but like any electrics the hardware will be practically free once developed. Compared to the cost of expanding existing freeway's, it will make sense finacially too. I figure it's maybe 10 years out.
American's are not likely to give up their cars for any sort of public transportation, no matter how impractical cars become with rising fuel costs, increasing travel times due to congestion, increasing insurance rates, etc. Most Americans have convinced themselves that they enjoy sitting in stop and go traffic, as long as it's in a car and not a bus. But if we could figure out a way to let them keep their cars, reduce pollution, reduce accidents, let them safely talk on their cell phones, and not have to build mile-wide highways I suspect a lot of us might go for it.
The streets are jam-packed with thousands of vehicles travelling in irregular serpentine patterns.
None of these machines (except mine, of course) contain any type of human intelligence, but it's interesting to watch the AI at work. At night the roads look like Conway's Game of Life running on a computer with bad RAM.
Expert systems allow some vehicles to negotiate left turns from right lanes and to outbrake school busses when entering a rotary.
Fuzzy logic is essential for speed control, stop lights, parking and many other mission-critical tasks.
Genetic algorithms tend to select the maneuvers which are least expected by other vehicles.
Task scheduling is done according to driver convenience. For example, turn signals are always lower priority than dialing a call on the mobile phone.
Most communications between vehicles is a crude form of "digital" communication.
Unfortunately, most of the vehicles are Windows-based which results in a high rate of crashes. Mack trucks seem to be better than average.
nanometers per light year is about as useful as giving it to us feet per yard. Nanometers per year on the otherhand would be (slightly) meaningful.
I just watched the video of the winning car and it's just not what I'd hoped for. All these cars are doing is following a line/wire.
I was just hoping that these cars were actually using sensors to keep track of the distance to the sidewalls of the track and the next turn.
It would be a good M. Eng. project for somebody to do this, using a half dozen laser distance sensors on the front, so that the car could go fast on straighaways, slow down for turns, and avoid sidewalls.
Does anyone know of a project like this?
With a good onboard computer, the car could build a model of the track as it went around, and calculate the optimal path & speeds to use on all subsequent laps. Using lasers or ultra sonic distance sensors would let the robot know when a turn was going to happen a lot sooner the the few inches of warning it gets in their setup. If you put an accelerometer in the car, you could even have it self-calibrate, discovering it's own acceleration curve, maximum lateral acceleration, and braking. It could then use those values to find the perfect path through the track on the second lap.
Life is too short to proofread.
Here's my picture
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Mamma look!
I hope I miscalculated this, but I figured 9ft/s is around 6mph. 9ft/1s:1mi/5280ft:3600s/1hr For those of you in modern nations, I apologize for the Imperial units. However; I am a speed-crazed American and albeit autonomous, if it can't go 45mph, I'm not impressed...
On a more serious note: Is the direction finding logic so intense that a greater speed can't be safely achieved?
I helped my roommate out on this project. The cars roll around the track following sensors. I helped him design some of the stuff. It can be difficult since the car has to interpret the signal into steering and speed control. I wish that UCLA had a specific class for this competition because other schools get the leg up on us because of this.
according to the article, it will be held in 2004, going all the way from LA to Las Vegas. it will be for autonomous robots, no human help allowed.
the winner will get 1 mio $, so get working.
they are quoting US media in the article, so there should be some infos in english somewhere.
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making up good sigs is a hard thing to do.
Maybe we'll have auto pilots in 100 years, but I don't see it happening in my lifetime. Yeah, an good autopilot could let cars run closer together, under normal circumstances, but if anybody gets a flat, people are gonna die. A computer just can't spot all the road hazards a person can. It's not going to know about that cinderblock that fell off a truck, or the deer that's running into the road.
Americans don't use public transportation, because public transportation here sucks.
Ride a bus in Germany, then ride a bus in NY. There's a world of difference. For me to use public transportation more often, it needs to become less dirty and less dangerous. For me personally, it would also need to be going 24/7.
One might also care to realize that things are laid out differently in America than they are in Europe. Ex: If I want to buy some milk, it would take me 40 minutes to walk to the closest place, and another 40 minutes to walk back. There is no mass transit I could take there even if I wanted to. America is BIG. I can get on the highway, drive for 3 hours and still be in the same state.
I think cars are impractical in certain areas (NYC, Boston, etc). In most places, they are a necessity. Where I live traffic is very efficient. I'm lucky enough to live in an area when most people actually know how to drive, and near a highway big enough to handle their traffic. I love driving on it. Even during rush hour, the average speed is 70.
Life is too short to proofread.
Strap yourself in son and prepare yourself for Mach 0.008!
"She's a West Texas girl, just like me" - G.W Bush Iraqis
The toy industry has had these cars on the market for years. You just put the track together, preselect the speed with a piece of duct tape on the trigger, and bam, autonomous race cars! At least until your cat steps on the track...
Someone should smack the responsible moderator upside the head.
Yeah, I agree that there is no way to do with I was talking about in 14 weeks. My idea would take a few grad students a year, doing nothing else. .?? g's
Did anybody try unsing accelerometers?
An optimal design would have (almost) no wheel slippage.
Maybe something like a feedback circuit, where it never allows itself to pull more than
I think the memorization approach just doesn't work unless you have a ceratin amount of instrumentation.
When I was really young my dad, brought home this robot that had ultrasonic distance sensors and used stepper motors to move itself. It looked a lot like R2D2. It tried to map it's environment, but wheel slippage caused it to suck horribly.
I think any design that would do successful mapping would have to use several sensors for speed data. If someone wanted to go all out (choosing this as their life's quest), they could monitor each tire's rotation individually, use an optcal sensor on the bottom or the vehicle (like an optical mouse), use an accelerometer, and use the data from laser range finders.
Life is too short to proofread.
Congrats on the winning car!
Life is too short to proofread.
This is a very simple control problem to solve... I actually think that you could do best in this competition by working on making the car faster; Most of the cars are going to have similar line following abilities.
"I'll have a Guinness, no wait, make that a Coors Light" -Grad student I work with, who shall remain anonymous...
My son is building one of these. He gets the parts from a magazine subscription. Light following/repulsion, sonar detection, line following. And seems to go pretty fast to boot.
MrCreosote Meow!Thump!Meow!Thump!Meow!Thump! "You're right! There isn't enough room to swing a cat in here!"
The winner was a constant-speed car. At 6MPH. Cars aren't learning the track and then driving it at a good speed; they're just dumb line-followers.
Battlebots are much cooler.
its a scale issue.. the cars are only 14 inches long... so it makes sense to say they travel in feet per second can you tell the difference between 6 and 7 miles per hour... NO, but you can relate to someone say 3 feet per second or 6 feet per second oh and by the way lets use the metric system
... why, that's almost sixteen and a half kilofurlongs per fortnight!
yes, we have no bananas
You just can't kludge up something like that in a few weeks. Anybody who's done power electronics looks at those numbers in awe. Plus they come with features like total self-protection against dead short, overheating, reverse polarity, etc. And all for about $100. Industrial motor controllers with comparable ratings cost thousands and are huge.
The very low resistance numbers are purely from the spec sheets of the N-channel MOSFETs they use to switch the power. It isn't some amazing work on the part of the motor controller designers. I can show you a basic motor controller design which with a few alterations can meets the specs you list.
Furthermore, this unit cannot really flow 640A. It can for tiny tiny fractions of a second, but the traces on the boards, the terminals for the wires to attach to, and even the wires you use to attach to these controllers cannot really flow 640A. All will melt down if they flow current of that magnitude for any amount of time. Even 100A probably cannot be sustained.
R/C speed controllers are quite amazing, but they are far from engineering marvels and they are not nearly as grand as you might think they are.
Interesting bit of information. Guess it ties in, really.
:)
Must be nice having that kind of job!
Michel
Fedora Project Contribut
So the litte robot cars going around the track at 6mph would be like real race car going 210mph.
Not so bad for a coupla undergrads, huh?
I have no real problem with "feet per second" as a measurement. But, out of the hundreds of articles that Timothy gets to choose from every day, he picked one that:
1. Linked to a video,
2. Was written poorly enough to be nearly incomprehensible, and
3. Called 9 fps "moving along pretty well."
Slashdot is jumping the shark. I'm just driving the boat.
I was expecting all sorts of bits coming together in this article, such as image/video processing, adding several images together, object recognition, the Heisenberg uncertainty principle as applied to video images (if it's blurred, you probably can't recognise what it is - but then, it's probably moving fast, so precise identicication takes a lower precedence than getting out of the way), attempts to put all gathered data into perspective, i.e., making a "map" of the outside world, and so on.
... which might actually be an improvement on some people's driving, come to think of it.
What do I get? Hey! I remember thses things from the eighties. You got a little bug with a couple of light sensors underneath, plus a red pen. You also got a thrashing when you covered the most available big flat white surface, which was the kitchen table, with roads (a.k.a. "scribbling").
OK, so they've gotten faster, but it looks like any car you upgrade with this tech will race down the centre marker of any highway you let it loose on
yes, we have no bananas
9 ft/s, eh? Can we have that in furlongs per fortnight please? I am so much more accustomed to the unit.
For the metrically non-challenged:
9ft/s = 2,7432 meter/s
thats = 9,87 km/h or 6,13 miles/h
And for collectors of odd figures and measurements: that speed equals 7769 nautical miles per presidential term.
+++ath0
CogniToy has a game that simulates the programming of these robots. They have a small web based demo Here If you go to their main page you can get more details on the full game
I believe McLaren F1 did this in the early 90's- with a full scale F1 car- not lapping at race pace, but allegedly, lapping.
So what is that in librarys of congress?
A few years ago when F1 had every driver aid under the sun there was a rumour, urban legend?, circulating that Mclaren had a car that was lapping Silverstone with out a driver.
I was hoping we would see the first car to win a GP without a human. Looks like Schumacher has achieved that now.
1. Linked to a video,
2. Was written poorly enough to be nearly incomprehensible, and
3. Called 9 fps "moving along pretty well."
1. Thus far I have seen little problem with the site hosting the video - the Berkeley network has multiple OC-12's to the outside world. And there was a good reason to link to the video, there are no other links to it, even from the linked webpages.
3. Did you watch the video? You'd have trouble keeping up without running a bit.
Steve VanDeBogart
Myself and too other guys did this as our Sr project for electrical engineering. It is more complicated than it sounds. We buildt six EM sensors. I built a motor control system to maximise power delivery. There was a 16 bit microcontroller board from P&E Micro, and a serial grafical LCD from Scott Edwards (thanks guys). We had a GUI running on the microcontrtoller so we could change settings and see what the sensors saw. My partners fabed an analog ASIC. Took two simesters.
All else being equal.
There are 3 basic factors that govern the throughput of a road.
1) number of lanes
2) spacing between cars
3) speed of cars
There are various others such as road condition, length of the cars, weather, etc. but these are the main ones considered when designing a roadway.
If you pick a number for the amount of traffic that is carried on a road, say 10K cars per hour; then divide by the number of lanes, say 2, you get 5K/hour/lane. Obviously, adding lanes will help, but we have not yet completed the formulation.
A car must have a finite length. This is deduced from the limiting case. If a car was infinitely long, the lane could never carry more than 1 car, ever.
The next point is spacing, since we are giving a car a finite length, and we do want the lane to carry more than one car, if there is the minimum of 2, then there must be a space between them. Again, the limits are natural. If we want to have more than one car, the space must be less than infinity and if we want to have maximum density, we could use zero. We can use this "zero option" to our advantage. To make things easier, we will dispense with the spacing and redefine the length of the car to be the distance from the front of one to the front of the next.
To see how speed influences things, we consider the limit of zero. Again it is obvious that our lane will only carry one car, or none, ever. For any speed greater than 0, the traffic capacity of the lane is simply car_length/speed.
Anything that can be done to decrease the length(spacing) or increase the speed will increase the traffic capacity of our lane. Spacing requirements can be reduced by making cars lighter, installing better braking systems and reducing the reaction time of the driver. Speed improvements can be had by making the road smoother, improving suspension design, and aerodynamics.
If you define congestion as any state where the lane is not producing its optimal throughput and reduced spacing is forcing a reduction in speed, then you can see that reducing the spacing(length) while maintaining speed is helpful and so is a speed increase while maintaining spacing.
We have made lighter cars, better brakes, smoother roads, improved aerodynamics and suspensions. Guess what's left?
Good judgement comes from experience, and experience comes from bad judgement.
- W. Wriston, former Citibank CEO
Amtrack's plight is...
In the 1930s, with the Great Depression reducing the market for personal automobiles, General Motors Corporation made a push to convert all U.S. transit systems to rubber-tired diesel buses. This effort was supported by Congress, which, in 1935, passed the Public Utility Holding Company Act, requiring most power companies to divest themselves of public transit operations. General Motors purchased transit systems across the nation through its subsidiary, National City Lines. They quickly turned around and bought diesel buses from the parent company and discontinued rail service. The rails were abandoned, often paved over in the city streets, although many ended up being salvaged for their steel once World War II began.
Thieved from here. Here's something a bit more cheerful though :)
Ali
Ph33r m3!!!
Listen you arrogant,stuck up, whiney bastards.
The site is in imperial measurements.
What is timothy supposed to do, tell them to change there measurement type, then post the story?
The Kruger Dunning explains most post on
last post!
In response to your 2nd comment, let me just say that I had absolutely no problem comprehending that article. The first full stop (i.e., period) ought to have been a comma, but I find that to be easily recognizable as a simple typing error and had no problem parsing any of the grammar. Perhaps you ought to think twice before you refer to something as "nearly incomprehensible": your inability to understand that article reflects poorly on your own intelligence.
Well, there are a few problems with the story. These aren't cars. They're 14 in. blocks with 4 wheels. I've never heard of "National Semiconductors" (although I'm familiar with "National Semiconductor"). These "cars" are line-following, not autonomous. This is a time-trial, not a race. Basically, my problem is that the poorly-written description in the story bears very little relation to the actual event.
Now -- the event was cool. After watching the video, you can immediately appreciate how difficult line following can be. I'm glad I read the story. I'm glad octothorpe submitted it. But I think the slashdot janitors should stop pretending they're editors if they don't want to edit.