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Robocabs Coming to Europe
Roland Piquepaille writes "Almost all of us can recall both good and poor memories of taxi rides when we arrived in a city we didn't know. This is why a short article from Spiegel Online, 'Bringing Robot Transportation to Europe,' caught my eye this morning. It briefly describes the European 'CityMobil' project which involves 28 partners in 10 countries at a cost of €40 million. This project plans to eliminate city drivers and three trial sites have already been selected. For example, in 2008, Terminal 5 in London's Heathrow airport will be connected to the car park by driverless electric cars along a 4-kilometer track. Read more for additional pictures and references about this project to make the roads in Europe's cities more efficient."
Did anyone else read that as "Robocrabs" and imagine some nasty STD of the future?
In Soviet Russia, car drives you!
"You're in a JohnnyCab!"
"Thank you, for you're cooperation."
"[...] driverless electric cars along a 4-kilometer track."
How is this different than EWR's monorail or other systems? I fail to see how this is a true automated cab system.
Information wants a fueled airplane waiting at the hangar and no one gets hurt.
Robot taxis have to be able to drive. So far, only a few cars have been able to do that, and that was in the desert with a truck-sized load of equipment. So don't expect them soon.
The government can't save you.
I think this marks the point where the future is right now. Or will be in three years. If it works. Hopefully. Either way, at least in principle, automated traffic like this could be faster, safer, and more effecient. And if this particular project doesn't work out as hoped, the next one will.
I'd love to see tests of robocars on subway tracks. Start with just GPS on the usual cars, to integrate live positioning into the signaling/switching system. Then put GPS on some empty cars steered from the central signaling/switching control stations. Then let people request destinations from originating stations. First big chains of cars carrying people between their shared endpoints. Then little individual cars between points. At first filling the spaces between traditional trains on traditional lines.
Eventually the "circuit switched" subways will be replaced with much more efficient, safe packet switched trains. Which link up along their shared segments for greater efficiency, but connect custom paths on demand.
--
make install -not war
You mean, like trains and subways?
I wonder if it will have an animatronic driver with minimal voice recognition just like the movie. ;-)
-------- -------- Support Wesley Clark for president!!!
A spanner in the works of your plan...
;-)
GPS tends to be a non-starter in subways or any covered area
Ripping an new rectum in the fabric of spacetime.
... welcome our new taxi-driver robot overlords!
Just hope they don't use Vista for voice recognition, or it will drive you to your aunt's house, instead of your mom's.
"You're in a Johnny Cab" While I doubt the cabs envisioned in this plan will possess the enraged mind of a serial killer like in the movie, and by serial killer I'm referring to corrupt and otherwise mysterious government or non-government agencies, I'm not sure what advantage they're going to have over other forms of transportation. I think the cabs might be a good idea if they were servicing people who were going to many different destinations - why do we take real cabs? because we're not always going to the same place that the bus or train is going to. I think the real advantage of this system would be to allow users to access many destination points along a given track. But the shortness of this track, as well as the limited number of destinations, makes me wonder why someone thought that little pod-cars would be better than a train/monorail as others have suggested. The pod-cars are cool enough, but let's build a city around them, not just a single end-to-end terminal run!
So you mean by 2008 we'll have reverted back to trollies and cable-cars? Perhaps people will even ride in electric vehicles that carry 30 or more people! Then everyone can get there for a tenth of the price! Oh wait, no that's a bus...
1) Take age old idea.
2) Do the same thing only with added benefit of key words.
3) Sell it as a new idea
4) Get fools to buy it.
5) PROFIT!!
Yeah, that's right, no "?????" step here.
I found a more insightful article that explains the advantage of this system over existing airport shuttle systems:
The difference for passengers will be not so much the journey time - which will be about four minutes - but how long they have to wait. Instead of huddling under a shelter for as long as 20 minutes as they currently do waiting for a bus, the pod will be at most a minute away.
it's not a taxi at all. it's a 4 km. rail. last time i rode a taxi, i gave the driver an address and the driver took me there, then i paid. this won't do any such thing, therefore to mr. european designer i have to say : YOU FAIL IT!!
And the blog he rode in on.
How is this not just a fancy commuter rail? Am I missing something?
where do you tag /. articles? where do you read others' tags?
The RUF is a better system than this. First, because it's dual-mode: you can drive (compatible) cars up onto the guideway. Second, because cars are privately owned (in addition to cars owned by the system operator and run as taxis within the system), the system operator will not have to come up with all the capital needed to run the line .... just the guideway and whatever number of taxis they want to run.
Don't piss off The Angry Economist
This is just a old transportation with a new spin. It's not an automated cab. it's just a smaller train.
Cabs do curb side service from your current location to your destination. Besides, I am glad cab drivers are safe and able to keep their jobs.
\
Thank you for riding with Johnny Cabs.
Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
Personal Rapid Transit http://en.wikipedia.org/wiki/Personal_rapid_transi t
Robots aren't very good drivers yet.
What we need are really cheap taxis that people can rent with a credit or debit card, drive a short distance, and pretty much just jump out and leave them. They need to be about as cheap as shopping carts - and even designed to fold up like shopping carts, so they can be racked conveniently in a compact space.
You'd probably rent the right to keep one at home over-night. You'd drive it a mile or two on surburban streets to a bus or lightrail terminal, where you'd rack it and get your "taxicard" back. Ride the transit, get off within a mile or two of where you need to be. Grab another taxi-cart, insert your taxicard, drive to your final destination. Rack it up with dozens or hundreds of others in the taxicart stall, and get your taxicard back again.
Reverse that, when going home. Each Taxicart stand would have extra taxicarts, and a computer system would note when a stand runs out completely, so that a couple of extras could quickly be delivered there. In the rare case that you arrive somewhere with an empty taxicart rack, you can punch a button to have one delivered, and get a credit for your inconvenience of having to wait.
The taxicart would be all electric, with maybe a 15 mile range, probably about 25mph maximum speed. It would re-charge while racked up. It'd also have a small tank of water - in the summer that'd be frozen (while on the rack) to provide maybe half an hour's air conditioning. In the winter, it'd be heated, for about the same duration of heat.
It'd be computer tracked with wireless and GPS - so the central computer could track units that get stalled. If you need to go somewhere without a rack, and leave the cart there, you could punch a button and pay to have it picked up - trucks would drive around just for that purpose - and again get your taxicard back. It'd have a plug too, so you could charge it up if necessary.
Seriously... does this guy have some sort of mental problems? He grabs every crappy article with stupid claims such as that egyptians already used nanotechnology just because some compounds they used to dye their hairs had particles as tiny as 5nm dia.
./ manages to make it to the front page. This time a press release that just uses the name "taxi" for what is commonly known as "trolley", with some added buzzwords.
Then, as a proof that lightning does strike the same spot twice, another stupidity submitted by him to
I got nine kids to feed...
I know what you're thinking. Did I forward 65,535 packets or 65,536 packets?
I have long thougt that owning cars is silly -- most cars are used for commuting. They drive for a few minutes, they sit, they drive for a few minutes, they sit. All those parking spaces -- streets in US residential areas are twice as wide as tey need to be so everybody can park their commute vehicles.
I figured sooner or later it would come to robotic cars -- you ave an appointment for your commute, the robocar drives to your home, picks you up, drives you to your workplace, drives away. No need for parking spaces, no need to produce nearly as many cars, and of course it would be extended to other uses, so you would always get the best car for each purpose, rather than trying to buy a car which will serve all your needs, even tose you seldom do like moving furniture or bringing home 1000 pounds of planting soil.
Me likes robocars.
Infuriate left and right
British people are always driving on the wrong side of the road so it's good if they can replace cabs with robot ones, lol. But we also need to replace every single Illinois driver with a robot because damn, those people don't know how to drive. I'm from Wisconsin btw :-D
now stop reading and go play Dance Dance Revolution!
Think what life would be like if no one needed to actually own their own car, if all car needs were met by robotaxis. I mean with enough of them around that you could pick one up within a minute at most. You would call for one on your cell phone -- it would use your cell phone location to know where to pick you up -- you'd say or type in the address -- when you get there, it charges your cell phone or robotaxi account or whatever -- it goes away to serve somebody else.
You could get by with one tenth the number of cars on the road today.
You could eliminate most parking at offices and factories and in residential areas.
You could reduce te number of cars sold every year by a factor of ten.
They could mostly be electric, thus quieter and centralizing the smog makers at power plants.
You could always get a vehicle more suited to your immediate needs. No need to buy a uge general purpose SUV or minivan or pickup just for the occasional furniture move or picking up loads of potting soil.
I am all in favor of tese robotaxis.
Infuriate left and right
What is this? The fifth or sixth Rolad story in the last 30 days? Hey Slashdot editors, good stories or bad, give OTHER people some front page space!
If you want news from today, you have to come back tomorrow.
When I think of an airport, I always remember how it is impossible to walk around. Not the terminal per say, but walking from the airport to somewhere off the airport terminal. (I distinctly remember the lack of walking areas in Sacramento). Anyways, I could see something like this making it even more difficult to walk around. Maybe nobody cares anymore, but I really enjoy a walk and I would hate to see that option disappear.
Trevor
"They need to be about as cheap as shopping carts - and even designed to fold up like shopping carts, so they can be racked conveniently in a compact space."
Dude, if you have to be unrealistic in your ideas, go all the way to personal transporters: "Beam me to work Scotty!"
If you want to see a realistic implementation of your idea (minus the folding cars -- forget rentals, if those were possible, they'd be in every household in Japan), look at http://flexcar.com/ -- the weakness is that you have to return to your origin, so that it is not appropriate for commuting or going to the airport.
Anyway, robots are fine drivers if you take the variability out of the system. Presumably, that's why these are on rails, to simplify the system to the point where they can navigate without too much risk of disturbance.
ScuttleMonkey and Zonk are to blame, IMO. CmdrTaco has stated that he thinks Roland's "submissions" are shit.
RoboEditors that posted links for popular digg stories would be more effective (and have less dupes).
Do you even lift?
These aren't the 'roids you're looking for.
How about some sort of monorail system with several 'trains' for the airport instead of using 19 separate cars. Looking at the pictures each car holds 4 people, with luggage that would be tight, totally of 76 passengers being moved at a time. People come in by the plane load much higher volumne than what the people movers can move quickly. The cars will be 'bumper to bumper' anyway when traveling. When the transport breaks down half way to the car park then what, get out and push? Hope someone is monitoring the transports?
At the international airport in Kualua Lumpur they have a robot train to pick up passengers and take them to another terminal. Here in Canada I felt like I was in a cattle corral with customs cowboys standing behind two way mirrors with prods ready.
This train of course runs on a set track but it does illustrate the idea.
I think this is a good development. I share the optimism of many experts who suggest we are already at or near peak oil. Currently we produce about 85 million barrels per day and at this point Saudi Aramco has admitted Ghawar is in decline up to 8% and the country as a whole is declining 2%. They join Kuwait which announced last November that Bergan is in decline. The next largest fields are Canatarrel and DaQing and these are in about a 14% decline along with Bergan.
These top four 4 feilds collectivly produce about 12-15% of the worlds conventional oils and they just illustrate the problem. Most countries and most oil fields are presently in decline.
The Jack#2 well announced by Cheveron last week may hearld in a new field potentially with 3-15 billion barrels. If so then this feild may be able to produce 750,000 barrels per day by the 2010-2015 time frame.
By 2015 if we subscribe to the idea that we're going to lose 5% production per year from the current 85 million barrels produced per day, then by 2015 we'll be short well over 15 million barrels of Oil per day (BOPD) of production compared to today. Tar Sands may add 2.2 million BOPD or even more. The Cheveron/Devon discovery may add almost another 1 million. But 85-85*(0.95^10) is a loss of 31 million BOPD and thus with this rough rough calculation I've already factored in everything we are likely going to be able to do and still some.
The bottom line is we need to cut consumption in a big way and the sooner the better. A HUGE percentage of the liquid fuels consummed, especially in the USA, is totally wasted. SUV"s sit six (6) abreast in grid lock traffic with their stereos cranked up and their air conditioners blasting. If we were to factor in the waste of people's lives - spending hours commuting to a job that may amount to little more than beauracratic paper shuffling, this alone might be considered the crime of the century.
But what we are doing to our planet and our future is even worse. All of that fuel wasted while commuting (often 1 person to a truck) is not available for useful purposes like industrial, chemical feedstocks, or by farmers to produce food.
Robocabs, if they are fuel efficient and small and sized for the job are an obvious answer.
Currently the USA burns over 20 million barrels of oil per day. If we get the SUV's off the road and replace them with a "Jonny cab" (from Total Recall - its a RoboCab) then we save lives because we get stupid drivers away from behind the wheel, we cut commuting time because the commute can be organised in a far more efficient manner than just plain old grid lock, and we might save enough fuel to save our precious butts in the process.
The thing is this fuel crisis is likely to be fully recognised as the beginning of a fundamental change to the human condition by 2010. Its still a few months to a few years off. Oil prices in the $70 range are the harbinger of things to come. We're ok for a short while. Next year we might not be so lucky.
ScuttleMonkey and Zonk are paid by Roland to post links to his AdBlog.
CmdrTaco may genuinely believe Roland's submissions are "shit", but he knows they aren't worthless, as Slashdot no doubt also benefits financially from Roland and his scams in some way or other.
Deny the above as much as you like ScuttleMonkey, Zonk, CmdrTaco et al, but you're wasting your breath---we know the truth already.
Show me a robo version that can take me from any point in the city to any address in a forth-ring suburb and I'll be impressed. A 4 Km track is no different than two subway stops in any city.
Glancing over it quickly, I thought it said robocops! I could just imagine them catching computer viruses and creating deadly "bot-nets" heh
I've heard there's a system somewhat like this, in Holland, I think.
It's called "bike stealing."
"Orthodoxy is unconsciousness" - Orwell
So are they gonna pipe in mid-eastern music, garlic smells, and strange bead thingies dangling from the mirrors to give it the real cabbie ambiance?
Table-ized A.I.
Never go for a ride in Release 1.0.
I can see it now - robot taxi drivers.
After defeating OCP and preventing the Delta City project from happening, Murphy (RoboCop) decided to settle down and become a taxi driver in Europe. He never realized that he would be competing with other retired robots for fares such as Optimus Prime and #5.
"Dead or alive, you're coming with me."
Ultimately, most people go with RoboCop.
I can't believe that the summary didn't include the above title. Personal rapid transit (PRT) is what people have been calling it for years, and is slightly different from the "robocabs" (think total recall) that it has been described as. The PRT system seems like an excellent solution for urban mobility from reading the articles on wikipedia, but it looks like there might need to be some heavy investment first. It's a good idea to check the wikipedia article (and the links of it) at http://en.wikipedia.org/wiki/Personal_rapid_transi t.
The dutch rail network has some lines wich split at a point so that the first half of the train goes in one direction and the last half in another. It is on a couple of lines, ALWAYS happens and is very clearly announded and printed on the signs. And each and every ride people get it wrong. Not every day, every single ride. Can you imagine the mess if a train is made up out of random parts going to random destinations?
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
I'm hoping this project is wonderfully succesful.
If they can make a system of automatically piloted vehicles within the ancient, twisted roads of Europe, it would be almost effortless to convert a similar system to the (comparatively) modern roads of America. Given our vast stretches of highway, an automated system could make long distance road travel less expensive and almost as effortless as train or even plane travel.
And your car probably wouldn't want to inspect your shoes before you get in either.
That already exists - I drove one yesterday (Antwerp, Belgium). Not electrical though, it was a regular car (Ford Focus).
It's car-sharing : if you need a car, you rent one for the time you need. You can pick one up from a few points around the city, and you have to leave it back there when you're finished. If you want to keep it longer (overnight, or when you need it for a weeekend), just keep it. You're paying with a special card (in this case, a RFID card), so that only authorized persons can borrow one, and you will be charged with the numbers of kilometers that you use.
It's a kind of automated car rental company, with a membership card.
Dooooood! Learn to recognize hyperbole!
The fact that the car park is 4kms from the terminal building tells you all you need to know about Europe.
Sent from my ASR33 using ASCII
a 4 minute bj!!!
NOT groups of people. It's a crucial development in public transport, and it's better than a computer driven car.
Transporting individuals means:
You can go directly or nearly directly to your destination.
You do not have to stop at intermediate stations to let people on and off.
You do not have to get out and change to different lines.
The transport pods wait for you, they don't run to a schedule so you don't have to wait at a station.
Being a form of off road transport means that:
It can be non stop.
There are no intersections.
There are no traffic lights.
There is no traffic congestion.
The average speed is remarkably close to the maximum speed of the vehicles.
The result is that for the average case, this form of transport is several times faster than other forms of public transport and importantly because of the non stop nature of A->B and the high average speed, it's faster than the car.
Taxi2000, an American equivalent to the ATS Ultra system has a capacity of 7200 vehicles per hour, it's the equivalent of a 3 lane motorway direct to the end of your street. But because the vehicles handle individuals, they are small and light the underlying guideway is also correspondingly light and therefore far cheaper than motorway, or conventional rail. Transport researchers have known since the 1960s that this is close to the optimal form of transport, unfortunately the computer technology to do it hasn't been available until recently.
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Use your head rather than your mouth, just for a second and think about the implications.
If you move a group of people.
The vehicle has to be big. It has to be heavy.
The underlying infrastructure to handle the vehicle has to be big, heavy and expensive.
The vehicle has to run along an average route, it can't go direct to your destination. You almost certainly will have to change vehicles to get to your destination.
The vehicle has to run to a schedule which means you have to wait for it.
The vehicle has to stop at every station along the route to let people on and off. This kills the average speed.
These are fundamental features of all forms of transport which move groups of people and fundamentally their performance sucks very badly indeed because of these features.
The system mentioned and others just like it completely remove these limitations to performance by transporting individuals rather than groups.
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Will it be as reliable as when they automated the baggage handling in Denver Airport. How will the driverless cabs respond to unplanned events like breakdowns or an obstruction. I once asked the conductor on the driverless docklands light rail what happens if there's an obstruction. He replied that well then we hit it.
davecb5620@gmail.com
I don't see how this is going to help prevent and solve unemployment. Most importantly, I don't think I would want to be taken somewhere by a piece of hardware, that I can't even ask a question, directions or some piece of information available exclusively to local humans (Could you take me to the nearest supermarket, pharmacy, whorehouse first, please?), and less so if it's running software, that's bound to have bugs...
or it can be small and continious.
people movers can hold 1-5 and go every thirty seconds, and change destinations on the fly.
every day http://en.wikipedia.org/wiki/Special:Random
I disagree. I agree that the system(or one based on the same principles) could as you say make more efficient use of the rail space and make a huge difference to traffic congestion. But... It should be privately financed, it's one of the few public transport systems which can be profitable.
Almost all existing forms of public transport are heavily subsidised by the taxpayer, 50% or so is common. Ironically this makes new transport systems like Ultra or Taxi2000 more difficult to implement. The key is less subsidy, not more. Sell off the rail system, including rails, stations and make it pay for itself. Ultimately this is going to mean a roll out of a PRT like system by the private sector, either in direct competition with rail or by the rail companies replacing traditional rail, and it'll be done faster, cheaper and more efficiently than a government would.
Deleted
We have this in London, www.streetcar.co.uk. They claim that you'll never be more than 5 to 10 minutes walk from a car.
I ride the Metro, you insensitive clod!
These have typically gone by the name of PRT - "Personal Rapid Transit" systems. Google it for a lot more information on what these systems can ultimately achieve.
m
:P
Back in the 70s, the big systems companies (later to be consumed by Raytheon, Boeing, etc.) was working on these mass transit systems to improve on some of the deficiencies of existing busses, subways, light rail, cars, taxicabs, etc. Ultimately they got out of the business by the 80s... I suppose municipalities aren't very visionary about such things, and it's probably much easier to just pour money into building more roads and federally-funded highways and pass/hide the vehicle costs to people to buy and maintain cars and not bother worrying about traffic congestion or pollution.
Anyway, there are a handful of PRT companies today (Ultra, Skytran, Taxi2000) still trying to push these systems out. Unfortunately, they seem responsible for lots of astroturf propaganda sites that all look and sound exactly the same. But ultimately, the decision to fund and build such broad advanced and integrated municipal systems are highly political. Yuck, politics.
So the only systems that seem to have a chance of being deployed are targetted towards campuses and airports. The only PRT-like thing in existence is a little 3-station tram system built by Boeing for WVU http://faculty.washington.edu/~jbs/itrans/morg.ht
But looks like Ultra is finally succeeding in putting more modern systems in Dubai and Heathrow. It's kinda ironic that these campus transit systems are primarily designed to shuttle people to and from a car parking lot
Oh well, one of these days we might have something that look and function a bit more like the PRT as shown in films like Minority Report. But it will take some visionary public officials to make it a priority, as well as some visionary systems engineering to define interface standards so the system can be smoothly maintained and upgraded over the decades. At least high fuel prices and increasing concern with environmentalism and sustainability may actually raise the public consciousness about this soon.
Off road transport also means great expense to install new lines "direct to the end of your street". More useful would be robotic cars that follow magnets laid in the street like the poster below describes.
Firstly, vehicles and associated infrastructure to move lots of people in one "hit" may be heavy and more expensive, but transport of this type benefits from the economy of scale and is more energy efficient. It's cheaper to run a single 8-litre, 6 cylinder diesel engine that shifts 50 people than to run 25 x 1.5 litre, 4 cylinder petrol engines to shift the same number (two passengers per car).
Add the overhead of a driver for each vehicle, and you can see it really does make a lot of sense to run busses.
Secondly, in the example quoted (the electric cars at heathrow) the route to the carpark is the same for all passengers, so the problem of not being able to "split up" and take passengers on individual routes does not exist.
The destination is also the same for all passengers, so the problem of stopping every now and then to pick up and set down passengers along the way (and this slow the trip down) doesn't really exist.
I, for one, welcome our Kiwi sewage to oil overlords. :)
No, I don't understand, tell me. ... look forward to hearing from you...
- In Europe cars are not as important as in other places?
- In Europe land is more heavily built up than elsewhere so they have to put car parks where they can?
- In Europe they don't help car drivers much?
- In Europe they put their emphasis on better public transport too and from airports so you don't really need a car?
So at #1 by a sizable margin over Roland, that makes prostoalex the uber ad whore?
If you want news from today, you have to come back tomorrow.
Robot vehicles which run on normal road will be subject to the same performance problems of cars. They will have to stop for traffic lights, intersections and will be stopped by traffic congestion meaning the average speed is dreadful, a substantial investment in upgrading roads with no performance benefit. Plus the complexity of the road network means that sophisticated AI which doesnt exist yet would be required to handle unforseen events.
You are quite correct that there is a substantial infrastructure investment required but it's a fraction of the cost of a road, a tiny fraction of rail and we can do it today.
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Basically your are describing 1998 technology, the Swiss CityCart. Which was in itself a progression of a Dutch experiment in 1972, the Witkar.
Be warned: both projects were ended quite quickly. There are a lot of technological, social en political pitfalls on the way.
It isn't a monopoly, it doesn't even carry a particularly large percentage of journeys, around 10% usually. Sure if you take it out of context and look at it without comparison to the other forms of transport which exist it is a natural monopoly. In reality there are viable alternatives which mean it isn't a monopoly situation.
Alternatives include buses, taxis, trams, private automobiles, bicycles, motorcycles, prt and feet. Subsidising rail simply reduces the investment the competition will make in their services and makes change to a better more optimal system less likely. Subsidising rail actually reduces the diversity of transport alternatives because the competitors can't compete.
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Sounds cool... although I fear the day that it is illegal to manually drive your car... *BEEP* Your ex-girlfriend has filed a report on you *BEEP* driving to station...
I hope they are also doing every conceivable test they can think of where one driver forces the CabBot off the road into another driver -- or forcing the CabBot into a quick stop, causing another driver to rear end the CabBot. I can see this happening alot especially when CabBot is empty between fares. Maybe bonus points for getting two CabBots to run into each other when empty?
Although maybe in a CabBot I'll be able to drive over 5 miles an hour in the city! *drives around small child pushed off of sidewalk*
These cabs are driverless...what's to keep passengers from having sex and urinating/defecating in them? At least, with privately owned taxis, the owner will occasionally hose out the back seat...
Doesn't anybody think of the poor young people studying philosophy, psychology, journalism, dramatics and ancient numismatics? Where should they get a decent job now?
from the to-stupid-for-words dept.
I personally trust a computer more to "stop for a red signal" than a driver, that maybe had a fight with his dear one the night before.
Well, you don't need driverless trains for that. Most modern railways, trams etc use automatic train control that will bring trains to a halt if there is a red signal (or another train on the same control section etc etc). Of course these systems have problems braking for people, cars, deers and other obstacles that don't have transponders which is why you still require drivers on many trains.
More information on the concept of Personal Rapid Transit sytems is available here for your enjoyment. The The Advanced Transit Association is an industry organization with many members from the PRT industry. The organization has a History of Personal Rapid Transit available.
There would be some extra two way traffic, but by definition, if traffic is returning to pick up a second commuter, then not all commuters are on the road at once. Considering how long the commute traffic lasts around here, I'd guess only 25% or so are on the road at any given time, and even if the robotaxis had to make a round trip for each with the return trip being empty, that's still half the cars you'd need total.
Besides, as someone else pointed out, by on the road I meant both parked and traveling, and part of the goal is to get rid of a lot of asphalt and parking lots, which robotaxis would do just fine. Even if the freeways were left intact, residential streets wouldn't be lined with parked cars doing nothing useful, and buildings wouldn't be surrounded by acres of parking lots doing nothing useful. I wonder what percentage of cities is wasted just parking cars? 20%? A lot, anyway, and that's what it would be wonderful to get rid of, in addition to reducing the amount of money wasted buying cars which do so little useful work by being parked so much of the time. And people would get the car needed for the task at hand, not the general purpose car which has to cover so many possibilities and thus is almost always bigger than needed.
Infuriate left and right