Submitted by brad on Fri, 2017-03-24 11:16.
The recently released national noise map makes it strikingly clear just how much air travel contributes to the noise pollution in our lives. In my previous discussion of flying cars I expressed the feeling that the noise of flying cars is one of their greatest challenges. While we would all love a flying car (really a VTOL helicopter) that takes off from our back yards, we will not tolerate our neighbour having one if there is regular buzzing and distraction overhead and in the next yard.
Helicopters are also not energy efficient, so real efforts for flying cars are fixed wing, using electric multirotors to provide vertical take-off but converting in some way to fixed wing flight, usually powered by those same motors in a different orientation. If batteries continue their path of getting cheaper, and more importantly lighter, this is possible.
Fixed wing planes can be decently efficient — particularly when they travel as the crow flies — though they can have trouble competing with lightweight electric ground vehicles. Almost all aircraft today fly much faster than their optimum efficiency speed. There are a lot of reasons for this. One is the fact that maintenance is charged by the hour, not the mile. Another is that planes need powerful engines to take off, and people are in a hurry and want to use that powerful engine to fly fast once they get up there.
Typical powered planes have a glide ratio (which is a good measure of their aerodynamic efficiency) around 10:1 to 14:1. That means for every foot they drop, they go forward 10 to 14 feet. Gliders, more properly known as “sailplanes” are commonly at a 50:1 glide ratio today and go even higher. Sailplane pilots can use that efficiency to enter slowly rising columns of air found over hot spots on the ground and “soar” around in a circle to gain altitude, staying up for hours. Silent flying is great fun, though the tight turns to rise in a thermal can cause nausea. Efficient sailplanes are also light and can have fairly bumpy rides. (Note as well that the extra weight of energy storage and motors and drag of propellers means a lower glide ratio.)
It is the silent flight that is interesting. An autonomous high efficiency aircraft, equipped with redundant electric motors and power systems, need not run its engines a lot of the time. While you would never want to be constantly starting and stopping piston powered aircraft engines, electric engines can start and stop and change speed very quickly. The motors provide tremendous torque for fast response times. It would be insane to regularly land your piston powered aircraft without power, figuring you can just turn on the engine “if you need it.” It might not be that crazy to do it in an electric aircraft when you can get the engine up and operating in a fraction of a second with high reliability, and you have multiple systems, so even the rare failures can be tolerated.
Both passengers and people on the ground would greatly appreciate planes that were silent most of the time, including when landing at short airstrips. It could make the difference for acceptance.
For a more radical idea, consider my more futuristic proposal of airports that grab and stop planes with robotic platforms on cables. Such a system would even allow for mostly silent takeoff in electric aircraft.
Making efficient aircraft VTOL is a challenge. They tend to have large wingspans and are not so suitable for backyards, even if they can hover. But the option for redundant multirotor systems makes possible something else — aircraft wings that unfold in the air. There are “flying cars” with folding wings which fold the wings up so the car can get on the road, but unfolding in the air is one of those things that is insane for today’s aircraft designs. A VTOL multirotor could rise up, unfold its wings, and if they don’t unfold properly, it can descend (noisily) on the VTOL system, either to where it took off form, or a nearby large area if the wings unfolded but not perfectly. An in-flight failure of the folding system could again be saved (uncomfortably but safely) by the VTOL system.
We don’t yet know how to make powered vertical takeoff or landing quiet enough. We might make the rest of flight fairly silent, and make the noisy part fairly brief. The neighbours don’t all run their leaf blower several times per day. But a combination of robocars that take you on the first and last kilometer to places where aircraft can make noise without annoyance if they do it briefly might be a practical alternative.
Planes that fly silently would not fit well with today’s air traffic control regiments that allocate ranges of altitude to planes. A plane with a 50:1 ratio could travel 10 miles while losing 1,000 feet of altitude, then climb back up on power for another silent pass. But constant changing of altitude would freak out ATC. A computerized ATC for autonomous planes could enable entirely different regimens of keeping planes apart that would allow this, and it would also allow long slow glides all the way to the runway.
Submitted by brad on Thu, 2017-02-09 15:26.
Caltrain is the commuter rail line of the San Francisco peninsula. It’s not particularly good, and California is the land of the car commuter, but a plan was underway to convert it from diesel to electric. This made news this week as the California Republican house members announced they want to put a stop to both this project, and the much larger California High Speed Rail that hopes to open in 2030. For various reasons they may be right about the high speed rail but stop the electric trains? Electric trains are much better than diesel; they are cleaner and faster and quieter. But one number stands out in the plan.
To electrify the 51 miles of track, and do some other related improvements is forecast to cost over 1.5 billion dollars. Around $30M per mile.
So I started to ask, what other technology could we buy with $1.5 billion plus a private right-of-way through the most populated areas of silicon valley and the peninsula? Caltrain carries about 60,000 passengers/weekday (30,000 each way.) That’s about $50,000 per rider. In particular, what about a robotic transit line, using self-driving cars, vans and buses?
Paving over the tracks is relatively inexpensive. In fact, if we didn’t have buses, you could get by with fairly meager pavement since no heavy vehicles would travel the line. You could leave the rails intact in the pavement, though that makes the paving job harder. You want pavement because you want stations to become “offline” — vehicles depart the main route when they stop so that express vehicles can pass them by. That’s possible with rail, but in spite of the virtues of rail, there are other reasons to go to tires.
Fortunately, due to the addition of express trains many years ago, some stations already are 4 tracks wide, making it easy to convert stations to an express route with space by the side for vehicles to stop and let passengers on/off. Many other stations have parking lots or other land next to them allowing reasonably easy conversion. A few stations would present some issues.
Making robocars for a dedicated track is easy; we could have built that decades ago. In fact, with their much shorter stopping distance they could be safer than trains on rails. Perhaps we had to wait to today to convince people that one could get the same safety off of rails. Another thing that only arrived recently was the presence of smartphones in the hands of almost all the passengers, and low cost computing to make kiosks for the rest. That’s because the key to a robotic transit line would be coordination on the desires of passengers. A robotic transit line would know just who was going from station A to station J, and attempt to allocate a vehicle just for them. This vehicle would stop only at those two stations, providing a nonstop trip for most passengers. The lack of stops is also more energy efficient, but the real win is that it’s more pleasant and faster. With private ROW, it can easily beat a private car on the highways, especially at rush hour.
Another big energy win is sizing the vehicles to the load. If there are only 8 passengers going from B to K, then a van is the right choice, not a bus. This is particularly true off-peak, where vast amounts of energy are wasted moving big trains with just a few people. Caltrain’s last train to San Francisco never has more than 100 people on it. Smaller vehicles also allow for more frequent service in an efficient manner, and late night service as well — except freight uses these particular rails at night. (Most commuter trains shut down well before midnight.) Knowing you can get back is a big factor in whether you take a transit line at night.
An over-done service with a 40 passenger bus every 2 seconds would move 72,000 people (but really 30,000) in one hour in one direction to Caltrain’s 30,000 in a day. So of course we would not build that, and there would only be a few buses, mainly for rush hour. Even a fleet of just 4,000 9 passenger minvans (3 rows of 3) could move around 16,000 per hour (but really 8,000) in each direction. Even if each van was $50,000 each, we’ve spent only $200M of our $1.5B, though they might wear out too fast at that price, so we could bump the price and give them a much longer lifetime.
These vans and cars could be electric. This could be done entirely with batteries and a very impressive battery swap system, or you could have short sections of track which are electrified — with overhead rails or even third rails. The electric lines would be used to recharge batteries and supercapacitors, and would only be present on parts of the track. Unlike old 3rd rail technology, which requires full grade separation, there are new techniques to build safe 3rd rails that only provide current in a track segment after getting a positive digital signal from the vehicle. This is much cheaper than overhead wires. Inductive charging is also possible but makes pavement construction and maintenance much more expensive.
Other alternatives would be things like natural gas (which is cheap and much cleaner than liquid fuels, though still emits CO2) because it can be refilled quickly. Or hydrogen fuel cell vehicles could work here — hydrogen can be refilled quickly and can be zero emissions. Regular fossil fuel is also an option for peak times. For example the rush hour buses might make more sense running on CNG or even gasoline. The lack of starts and stops can make this pretty efficient.
In such a system, you can also add new “stations” anywhere the ROW is wide enough for a side-lane and a small platform. You don’t need the 100m long platform able to hold a big train, just some pavement big enough to load a van. You can add a new station for extremely low cost. Of course, with more stations, it’s harder to group people for nonstop trips, and more people would need to take two-hop trips — a small van or car that takes them from a mini-station to a major station, where they join a larger group heading to their true destination.
Of course, if you were designing this from scratch, you would make the ROW with a shoulder everywhere that allowed vehicles to pull off the main track at any point to pick up a passenger and there would barely be “stations” — they would be closer to bus stops.
Getting off the track
Caltrain’s station in San Francisco is quite far from most of the destinations people want to go to. It’s one of the big reasons people don’t ride it. Vans on tires, however, have the option of keeping going once they get to the station. Employers could sponsor vehicles that arrive at the station and keep driving to their office tower. Vans could also continue to BART or more directly to underground Muni, long before the planned subway is ready. Likewise on the peninsula, vans and buses would travel from stations to corporate HQ. Google, Yahoo, Apple and many other companies already run transit fleets to bring employees in — you can bet that given the option they would gladly have those vans drive the old rail line at express speeds. On day one, they could have a driver who only drives the section back and forth between the station and the corporate office. In the not too distant future, the van or bus would of course drive itself. It’s not even out of the question that one of the passengers in a van, after having taken a special driving test, could drive that last mile, though you may need to assure somebody drives it back.
I noted above that capacity would be slightly less than half of full. That’s because Caltrain has 40 at-grade crossings on the peninsula. The robotic vehicles would coordinate their trips to travel in bunches, leaving gaps where the cross-street’s light can be turned green. If any car was detected trying to run the red, the signal could be uploaded to allow all the robotic vans to slow or even brake hard. Unlike trains, they could brake in reasonable amounts of time if somebody stalls on the old track. You would also detect people attempting to drive on the path or walk on it. Today’s cameras and cheap LIDARs can make that affordable. The biggest problem is the gaps must appear in both directions (more on that in the comments.)
Over time, there is also the option in some places to build special crossings. Because the vans and cars would all be not very high, much less expensive underpasses could be created under some of the roads for use only by the smaller vehicles. Larger vehicles would still need to bunch themselves together to leave gaps for the cross-traffic. One could also create overpasses rated only for lightweight vehicles at much lower cost, though those would still need to be high enough for trucks to go underneath. In addition, while cars can handle much, much steeper grades than trains, it could get disconcerting to handle too much up and down at 100mph. And yes, in time, they would go 100mph or even faster. And in time, some would even draft one another to both increase capacity and save energy — creating virtual trains where there used to be physical ones.
And then, obsolete
This robotic transit line would be much better than the train. But it would also be obsolete in just a couple of decades! As the rest of the world moves to more robocars, the transit line would switch to being just another path for the robocars. It would be superior, because it would allow only robocars and never have traffic congestion. You would have to pay extra to use it at rush hour, but many vehicles would, and large vehicles would get preference. The stations would largely vanish as all vehicles are able to go door to door. Most of the infrastructure would get re-used after the transit line shuts down.
It might seem crazy to build such a system if it will be obsolete in a short time, but it’s even crazier to spend billions on shoring up 19th century train.
What about the first law?
I’ve often said the first law of robocars is you don’t change the infrastructure. In particular, I am in general against ideas like this which create special roads just for robocars, because it’s essential that we not imagine robocars are only good on special roads. It’s only when huge amounts of money are already earmarked for infrastructure that this makes sense. Now we are well on the way to making general robocars good for ordinary streets. As such, special cars only for the former rail line run less risk of making people believe that robocars are only safe on dedicated paths. In fact, the funded development would almost surely lead to vehicles that work off the path as well, and allow high volume manufacturing of robotic transit vehicles for the future.
Could this actually happen?
I do fear that our urban and transit planners are unlikely to be so forward looking as to abandon a decades old plan for a centuries old technology overnight. But the advantages are huge:
- It should be cheaper
- Many companies could do it, and many would want to, to fund development of other technology
- It would almost surely be technology from the Bay Area, not foreign technology, though vehicle manufacturing would come from outside
- They could also get money for the existing rolling stock and steel in the rails to fund this
- The service level would be vastly better. Wait times of mere minutes. Non-stop service. Higher speeds.
- The energy use would be far lower and greener, especially if electric, CNG or hydrogen vehicles are used
The main downside is risk. This doesn’t exist yet. If you pave the road to retain the rails embedded in them, you would not need to shut down the rail line at first. In fact, you could keep it running as long as there were places that the vans could drive around trains that are slowing or stopping in the stations. Otherwise you do need to switch one day.
Submitted by brad on Fri, 2016-12-02 00:42.
I believe we have the potential to eliminate a major fraction of traffic congestion in the near future,
using technology that exists today which will be cheap in the future. The method has
been outlined by myself and others in the past, but here I offer an alternate way to
explain it which may help crystallize it in people’s minds.
Today many people drive almost all the time guided by their smartphone, using navigation
apps like Google Maps, Apple Maps or Waze (now owned by Google.) Many have come to
drive as though they were a robot under the command of the app, trusting and obeying it
at every turn. Tools like these apps are even causing controversy, because in the hunt
for the quickest trip, they are often finding creative routes that bypass congested
major roads for local streets that used to be lightly used.
Put simply, the answer to traffic congestion might be, “What if you, by law, had to
obey your navigation app at rush hour?” To be more specific, what if the cities and towns that own
the streets handed out reservations for routes on those streets to you via those apps, and
your navigation app directed you
down them? And what if the cities made sure there were never more cars put on a piece of road
than it had capacity to handle? (The city would not literally run Waze, it would hand out route reservations to it, and it would still do the UI and be a private company.)
The value is huge. Estimates suggest congestion costs around 160 billion dollars per year in the USA, including 3 billion gallons of fuel and 42 hours of time for
every driver. Roughly quadruple that for the world.
Road metering actually works
This approach would exploit one principle in road management that’s been most effective
in reducing congestion, namely road metering. The majority of traffic congestion is caused,
no surprise, by excess traffic — more cars trying to use a stretch of road than it has the capacity
to handle. There are other things that cause congestion — accidents, gridlock and
irrational driver behaviour, but even these only cause traffic jams when the road is near
or over capacity.
Today, in many cities, highway metering is keeping the highways flowing far better than they
used to. When highways stall, the metering lights stop cars from entering the freeway as
fast as they want. You get frustrated waiting at the metering light but the reward is you
eventually get on a freeway that’s not as badly overloaded.
Another type of metering is called congestion pricing. Pioneered in Singapore, these
systems place a toll on driving in the most congested areas, typically the downtown cores
at rush hour. They are also used in London, Milan, Stockholm and some smaller towns, but have never caught on in many
other areas for political reasons. Congestion charging can easily be viewed as allocating
the roads to the rich when they were paid for by everybody’s taxes.
A third successful metering system is the High-occupancy toll lane. HOT lanes take
carpool lanes that are being underutilized, and let drivers pay a market-based price to use them
solo. The price is set to bring in just enough solo drivers to avoid wasting the spare
capacity of the lane without overloading it. Taking those solo drivers out of the other
lanes improves their flow as well. While not every city will admit it, carpool lanes themselves
have not been a success. 90% of the carpools in them are families or others who would have
carpooled anyway. The 10% “induced” carpools are great, but if the carpool lane only runs at
50% capacity, it ends up causing more congestion than it saves. HOT is a metering system
that fixes that problem. read more »
Submitted by brad on Wed, 2016-07-13 10:05.
The success of carpool apps
The cell phone ride hail apps like Uber and Lyft are now reporting great success with actual ride-sharing, under the names UberPool, LyftLines and Lyft Carpool. In addition, a whole new raft of apps to enable semi-planned and planned carpooling are out making changes.
The most remarkable number I have seen has Uber stating that 50% of rides in San Francisco are now UberPool. With UberPool, the system tries to find people with overlapping ride segments and quotes you a flat price for your ride. When you get it, there may already be somebody there, or your car may travel a small bit out of your way to pick up or drop somebody off. It’s particularly good for airports, but is also working in cities. The prices are often extremely good. During a surge it might be a much more affordable alternative.
It’s often been observed that as you watch any road, you see a huge volume of empty seats go down it. Even partial filling all those empty seats would make our roads vastly more efficient and higher capacity, as well as greener. Indeed, the entire volume of most transit systems could probably be easily absorbed, and a great deal more, if those empty seats were filled.
The strongest approach to date has been the hope that carpool lanes would encourage people to carpool. Sadly, this doesn’t happen very much. Estimates suggest that only 10% of the cars in the carpool lane are “induced” carpools — the rest are people like couples who already would have gone together. As such, many carpool lanes actually increase congestion rather than reducing it, because they create few induced carpools and take away road capacity. That’s why many cities are switching to HOT lanes where solo drivers can pay to get access to excess carpool lane capacity, or allowing electric/PHEV vehicles into the carpool lane.
Most carpool apps today have a focus on people who are employees of the same company. Companies have had tools to organize carpools for ages, and this works modestly well, but typically the carpools are semi-permanent — the same group rides in together each day, sometimes trading off who drives. The companies provide incentives like cash and special parking.
The new generation of carpool apps (outside Uber) tend to focus on people at the same company, and as such they mostly work with big companies. There they can add the magic of dynamic carpooling, which means allowing people to be flexible about when they come and go, and matching them up with different cars of other employees. This makes sense as an early business for many reasons:
- People can inherently trust their co-workers
- Co-workers naturally share the same workplace, so you only have to find one who live within a reasonable distance
- Companies will subsidize the carpooling for many reasons, including saving them parking.
The subsidies can often include a very important one, the guaranteed ride back. Some of these apps say that when you want to leave, if they can’t find a carpool going near your house, they will provide alternate transportation, such as transit tickets or a Taxi/Uber style ride. This gives people the confidence to carpool in with one dynamically assigned group, knowing they will never be stuck at the office with no way home. Independent carpool services can also offer such a guarantee by adding a cost to every ride, but it’s easier for a company to do it. In fact, companies will often pay for the cost of the apps that do this, so that all the employees see is the car operating cost being shared among the poolers.
What has not happened much today is the potential of the multi-leg carpool, where you ride in one car for part of the trip, and another car (or another mode) for another part. Of course changing cars or modes is annoying compared to door-to-door transportation, though it’s the norm for transit riders.
Today, must carpool apps will have the driver go slightly off their route — often off the highway — to pick up a rider or return one home. (Normally the morning destination is a commercial building, usually the same building.)
A multi-leg service has some similarities to the concepts of multi-leg robocar transit I outlined previously. In one vision, the actual carpool sticks to highways and arterial roads, and never deviates from the expected route of the driver or any of the poolers. Poolers get to the carpool by using some other means — including a private Uber style ride — and then join it for the highway portion. If they are not going to the same place as other poolers, they can also use such a ride at the other end, though having two transfers reduces the appeal a fair bit.
This “last mile” leg can be something like Uber, or transit, or a bicycle (including one-way bicycle systems) or a “kiss and ride” drop-off by a spouse, or even another carpool. The difference is to make it dynamic, with live tracking of all parties involved, to reduce waits at the transfer points to very short times. (With robocars and vans, the waits will be measured in seconds, but human drivers won’t be that reliable.)
In spite of the inconvenience of having to do a transfer, if the wait is short, it’s better than the downsides of the driver or other poolers having to go far off the highway to handle a fellow pooler, and there can even be financial incentives to make things smooth.
Transfer points on arterials
The main barrier in the way of a truly frictionless transfer is the absence of good and easy places to do the transfer in many locations. This might be something that highway planners should consider in building or modifying future roads. The benefits can happen today, well before robocars, so it can get on the radar of the planners today. When the robocar transit arrives, tremendous benefits are possible.
Today, there is something a bit like this. In many cities, there are bus lines that run on highways. In some cases, bus stops have been built embedded in the highway, allowing the bus to stop without fully leaving the highway. A common example can be found on intersections which have a private on-ramp/off-ramp lane which stops mergers from interfering with primary traffic. Sometimes these are just off to the side of the regular highway, but in all cases the bus pulls off the highway and then into the bus stop. Riders have some safe path from the non-highway world, including bus stops on regular streets and arterials.
In the fast-transfer world, you want something like this, though you don’t necessarily need a path to other roads. A rider brought in an Uber can be dropped off there, and in interchanges with a private collector lane, the car that drops the rider off can easily get back onto the regular road in the opposite direction.
In the map is an intersection that already has all the ingredients needed for carpool transfer points — collector lanes, long ramps and lots of spare space. Most intersections are not as adaptable as this one, but new and reconstructed intersections can be adapted in much less space. In addition, transfer points may be possible in the center median, if there is room, under bridges, through the installation of a staircase from the bridge. (If there is no elevator, the disabled can be brought to the transfer point through a longer route that goes on the highway.) This is a common layout for transit lines which run down the median.
Full cloverleaf is better for the placement of transfer points, though there are other places they can go in other intersection designs. (It’s become popular of late to replace full coverleaf intersections with the parclo design that comes from my home town of Toronto. This change is mostly done to avoid the complex merge and tight turns of a full cloverleaf, though robocars can handle the full clover just fine. You can easily put some transfer points in a parclo, you just have an extra minute or two spent by the stopping carpool.
Transfer points are dirt cheap infrastructure, pretty much identical to bus stops, though ideally they would use angled parking so vehicles can come and go without blocking others. You do want space for a van or even a bus to come when you have found a super-carpool synergy, as will probably be the case at the peak of rush hour. Of course, if the volume of poolers grows very high, it justifies making larger transfer points and more of them. For super peak times, it’s OK to use transfer points that are just off the highways (where parking lots to do this are plentiful) because with high volume, pools are making just one stop to pick up passengers and can handle a small detour.
Transfer with parking
Of course, today the easiest way to do these carpools is with “carpool lots” not too far from the highway — places with spare parking which allow carpool riders to drive to the lot to meet their carpool driver. Indeed, carpoolers should be those who own cars because the first goal is to take a car off the road that otherwise have driven, and the second goal is to fill the empty seat with somebody who would otherwise have been on transit.
It can be difficult to get lots of parking convenient to the highway. One carpool lot I use has room for only about 50 cars. Nice that it’s there, but it takes no more than 50 cars off the road. At scale, one could imagine it being worthwhile to have shuttles from parking lots to on-highway transfer points, though nobody likes having to do 3 or 4 legs for a trip unless it’s zero wait time. If Robocars were not coming, one could imagine designing future highways with transfer points connected to parking lots. The people of the past did not imagine robocars or cell phone coordination of carpooling.
Submitted by brad on Sun, 2016-02-21 19:34.
I have a big article forthcoming on the future of public transit. I believe that with the robocar (and van) it moves from being scheduled, route-based mass transit to on-demand, ad-hoc route medium and small vehicle transit. That’s in part because of the disturbingly poor economics of current mass transit, especially in the USA. We can do much better.
However, long before that day, there is something else that could be done. Many mass transit systems shut down at night. Demand is low, and that creates a big burden for the “night people” of the world, who are left with taxis and occasional carpooling, or more limited night bus service.
I think transit agencies should make a deal with companies like Uber to operate their carpool services (UberPool and LyftLines) during transit closure hours, and subsidize the rides to bring them down equal to, or closer to a transit ticket. This could also be the case for other seriously off-peak times, like weekends and holidays.
Already the typical transit ticket in the USA is heavily subsidized. The real cost of providing a transit ride is much higher. In the transit-heavy cities, fares pay about 50-60% of operating cost, but in some cities it’s only 15-20%. The US national average is around 33%. And that’s just operating cost, it does not include the capital costs in many cases. One thing that pushes the number the wrong way is operation during off-peak hours on lightly loaded vehicles. So while the average ride may cost $6 to provide, it can be more at night. Already the mobile-summoned based carpools are close to that price. (For promotions, they have actually gotten to less. They also subsidize to get going, though.)
There are some big issues. First, not everybody has a smartphone, a data plan or even a phone. You need a method for those without them to summon a ride. You could start with an 800 number so any phone (or the few remaining payphones) could summon a ride. You could also make mini-kiosks by building a protective case and putting a surplus tablet at every subway stop and many bus stops.
Another issue is that these services, particularly the carpool versions, depend on not having anonymous riders. People feel much safer about carpooling with strangers if those strangers can be identified if there is a problem. Transit riding is anonymous, and should be. The solutions to this are challenging. On top of all this, riding in a mobile-hail car is never paid for with cash, and the drivers are not going to accept cash. At the least, this means you would need to provide tickets that people buy (from machines at stations or in advance) which the driver can scan with their phone. So no just deciding to take a ride with cash. Transit cards are an other issue, though there is no requirement that they work, because at least at first, this service is meant for hours when the transit was not even running, so it’s OK if it’s an extra cost.
Finally, there is the issue that this is too good. A ride in a private car vs. a late night transit bus, for the price of a bus? People will over-use it, and that would of course get the Taxis angry, though there is no reason they could not participate as they are all going to supporting mobile-app hail. But the subsidy may be too expensive if people over use it.
One solution to that is to only allow it to take you between transit stops. Even that’s “too good” in that it may be faster than the transit, and much faster if the trip involved changes, especially changes during limited service times. You could get extreme and only allow it between limited sets of stops, or require 2 rides (for the same price) to simulate having to change lines. This also makes carpooling much easier, as the drivers would mostly end up cruising close to the transit lines. IF they do it in vans it could be quite efficient, in fact.
We probably don’t need to go that far in limiting it, but we could. You could tune the ease and quality of the service so the demand is what you expect, and the subsidy affordable. And the ride companies could actually use this as a way to gain extra revenue. They could offer you a door to door ride with a subsidy for the portion that would have been along the transit line. For example, today you can take Uber to the subway station, ride the subway for $2 and then take Uber from the end station to your destination, and that can be cheaper than just taking the Uber directly. This ride could be offered at some subsidized price and keep up the volume. The taxi companies can either get into the 21st century and play, or not compete.
Aside from improving transit service (by making it 24 hours) this also lets us experiment with the future world of ad-hoc demand based public transportation, when we get to the future where the vans are driving themselves. More on that to come.
Submitted by brad on Tue, 2016-01-19 22:43.
I’ve been electric car shopping, but one thing has stood out as a big concern. Many electric cars are depreciating fast, and it may get even faster. I think part of this is due to the fact that electric cars are a bit more like electronics devices than they are cars. Electric cars will see major innovation in the next few years, as well as a decline in their price/performance of their batteries. This spells doom for their value. It’s akin to cell phones — your 2 year old cell phone still functions perfectly, but you dispose of it for a new one because of the pace of innovation. Electric cars are not at that pace, but they are skirting the phenomenon.
When it comes to Robocar, I remind people that the computer will be the most important part of the car, not the engine or other features. And the computer and software are on the Moore’s Law curve, like your phone. The battery system is not like this, but digital features are becoming more and more important parts of every car.
The most obvious cause of the big depreciation is not related to the cars. There is a $7500 federal tax rebate on a new electric car, so the moment you drive it off the lot, its blue book value drops an additional $7500. In addition, different states offer credits from of up to $5,000, and unless you take the car out of state, that amount will also drop off the value. This is the primary culprit for the huge depreciation numbers, but there is more.
Perversely, people with higher incomes don’t get California’s $2,500 credit, so for them, buying used is a very wise idea, because somebody else got the credit, and it’s reflected in the price of the car. Of course, if you are rich enough, you may tolerate paying $2,500 more than everybody else for the new car. In fact, if not for the sales tax, it would be a good strategy to get somebody else to buy a car for you and get the credit, then buy it from them. Or take over a lease (getting to that…)
There are rumours that vendors might even be trying to subsidize against this depreciation to avoid a collapse in the price of their cars. After all, such low used car value discourages confidence in the car (and steals away buyers of new cars.) Rumours suggest Nissan has been known to offer incentives to get people to keep their lease-returns rather than take them back, and there are stories of even Teslas getting low prices at auction, though in the retail market they have actually done pretty well.
The Leaf is the most popular electric car, and only it and the Tesla are real market cars from big players. The other cars are all “compliance” cars, made by companies who must meet quotas of green vehicles. The 2015 Leaf has a cited range around 80 miles, and users report a real range on the highway closer to 60 miles. For me, that means a car that can’t take me to San Francisco and back. The Leaf would handle a large fraction of my trips around Silicon Valley, but not being able to go to SF is a major detriment in this town. So I decided not to get a 2015 Leaf.
Better cars keep getting pre-announced
That decision was magnified when Nissan announced the 2016 Leaf would be able to do 107 miles. Technically, that’s enough for the San Francisco trip, though in reality it’s just on the edge. Any charging would allow the trip, including a 5 minute (“gas pump” level) stop at a DC supercharger (if nobody else is using it.) So I was waiting for that car to come out when…
They announced the Chevy Bolt, a $30K car (after rebate) with a 200 mile range. Finally a reasonably priced car with enough range. And then rumours circulated of a similar range in the 2017 Leaf — it needs to if it will compete, and so every other car needs to as well. Who will buy a 100 mile 2016 car when a 200 mile 2017 car for not much more is being promoted?
Of course, in a year, something even more appealing than the Bolt will be announced. While the Bolt’s range is enough for 99% of my drives (leaving out only Lake Tahoe and road tripping) there is still much that can improve — other parts of the car, the electronics, and of course the battery pack getting even cheaper at that range.
Every year, cars get a little bit better, but we’re in for a period of about 5 years in electric cars where each new year is a lot better, and that’s trouble for people trying to sell them if the customers figure that out. A cell phone is cheap enough to throw out after 2 years. A car is not. To top it off, in a few years the robocar features will start getting more serious (starting with the first no-supervision traffic jam assist) and so other parts of the car will also be on the Moore’s Law curve.
The battery is probably not on that curve, but it’s on a good one. The Bolt’s 200 mile range is a result of an expected reduction of battery cost from $500/kwh a couple of years ago to $200/kwh by 2020, and that’s without any breakthroughs or new chemistry. (It is speculated the Bolt’s battery cost will already beat that $200 number.) Breakthroughs — which sometimes come when enough money is pushing the process — could easily do much more.
Robocars have an answer to this rapid depreciation. If they are used as Taxis, they can survive. The typical New York Taxi drives 62,000 miles each year and wears out in 5 years. Personal cars take 19 years to wear out, and go around 200,000 miles. Robotaxis will wear out and be scrapped after just 5 years, which means it is less of a burden when they are 4 years old and obsolete from a technology standpoint. (We may also design these vehicles to make it easy to give them hardware upgrades so their electronics can keep pace.)
Personal robocars have it harder. Your 4 year old personal vehicle is going to look like crap compared to the new ones. It will get software updates to match them (which is vital) but without hardware updates it will, like an old iPhone, no longer even be able to handle the software updates. If you buy a personal robocar, get one where it’s easy to swap out the hardware, and expect to pay the cost of this.
Wear and tear of electric cars
The battery is the lifeblood of the electric car. No matter how new the rest is, a reduced range is a deal-killer for most buyers. Indeed, some predictions say the rest of the power train should wear out more slowly than traditional cars, so the depreciation is unfair in some ways.
Battery swap is an option on some electric cars, but that’s a big cost to pay over what you planned to pay. Older battery packs will still work, but deliver less range. Owners will salivate for new packs that are cheaper, lighter, fresher and possibly even higher capacity than what they have. That’s all good, but if you buy an electric car with a pack only good for 4 years at today’s prices, you’ve lost all the economies the electric car hopes to give you. Of course, robocars and especially robotaxis can manage their batteries for much longer life
It might make sense to buy a 2012 Leaf for $8,000 and pay $5K to add a battery pack to it that’s brand-new, giving you a car close to matching a new one in certain ways.
With all this, why look at electric cars today? For me, my electricity bill would actually go down due to metering differences, and of course my gasoline bill would drop too. And they are zippy and fun to drive and quite green with California’s (relatively) green energy grid. And because of this depreciation, used ones are a major bargain. The buyers of new cars (and the federal government) took the hit on a new electric, but you can pick up a 2012 Leaf for $8,000. That’s because all those 2012 units are coming off their leases, and people want them a lot less with those fancier models out there. (In addition, it is known the 2012 had some battery life issues fixed in 2013.)
A lot of people are leasing electric cars. Leasing has one financial advantage (you pay sales tax only on the depreciation you take, rather than the whole car) and otherwise it’s a bad idea unless you’re sure the vendor has guessed badly on the residual value of the car after the lease. With electric cars, you take so much of the depreciation that the tax advantage is not so great. But many electric owners are leasing. The $2500 tax credit in California can often pay for the downpayment, making it easy to come up with the money, and owners are, with good reason, willing to let the vendor take the risk on battery decay and mega-depreciation. Vendors are not idiots, though, and so their residual values are low, but perhaps not low enough. Of course, if you know better cars are coming and are sure you only want the car for 2 years, leasing can ease your legwork.
On the other hand, you can sometimes take over the lease of another electric car owner, letting them suffer the “due at signing” downpayment (which often exceeds all the monthly payments on a short lease) and giving you a car for a very short time, which might be a wise choice with all the new vehicles coming down the pipe.
Submitted by brad on Sun, 2015-10-04 11:07.
Recently I did a road trip through Portugal. I always enjoy finding something new that they are doing in a country which has not yet spread to the rest of the world.
Along a number of Portuguese roads, you will see a sign marked “velocidade controlada” — speed control — and then a modest distance down the road will be a traffic light in the middle of nowhere. There is no cross street. This is an interesting alternative to the speed bump or other “traffic calming” systems.
At the sign a radar gun measures your speed. If you are over the limit, then as you approach the light, it turns red. It turns red for you, and also anybody behind you and the oncoming traffic.
The result is people slow down for these signs to the limit. Far more effectively than any speed bump, and without the very annoying bump. Mostly this is done on faster roads than the quiet residential streets that have speed bumps, and of course traffic lights cost more than speed bumps, at least today.
The social dynamic is interesting. Even though many of us are scofflaws when it comes to the speed limit, most are much more religious about a red light. Even a red light like this one where there is no physical danger to running the red light, just the fairly unlikely risk of a stronger ticket. Strangely, though both speeding and running this light are both just violations of the law, I never saw anybody run one, and drivers who were total speed demons elsewhere quickly slowed down before these signs. (People know where they are, so they aren’t a general speed reducer, but rather more like a speed bump in cutting speed in one particular place.)
Added to this is the element of public shame. If you trigger this light, you stop everybody around you too. If you’re a sociopath, this won’t concern you, but for most there is a deep shame about it.
Today, as noted, a traffic light and radar gun are a moderately expensive thing. These lights are not nearly as expensive because they don’t require the complex intersection survey and programming of sometimes 20-30 real lights, but they still need a pole, and electricity, and weather hardened gear. In the future, I predict this sort of tech will get quite inexpensive, possibly cheaper than a speed bump. You could imagine making one with solar power and LEDs which only displayed the red light, not the green, and so needed no external power for it. They need not be on all the time — in fact if the batteries got low, they could just shut down until they recharged. The radar and communications link could also become quite cheap.
Of course, I would like to see this combined with more reasonable speed limits. I have pointed out before that the French Autoroute approach of a realistic limit of 130km/h that everybody obeys and where you really get tickets if you exceed it is much better than the US approach of a 65mph limit that 90% of drivers disregard. This system is much better than the speed bump. Speed bumps hurt cars and impede emergency vehicles. Emergency vehicles can blow through these. These could even vary their speed based on conditions and time of day.
Robocars of course would know where all these are and never trigger one, even if the occupants have commanded the vehicle to exceed the limit. But this is mostly a technology for human drivers. It is halfway along the path to “virtual infrastructure,” which is how roads and traffic control will work in the future when every car, human driven or not, uses a maps and data over phones to know the road, rather than signs and lights.
Submitted by brad on Mon, 2015-03-30 14:04.
I often speak about deliverbots — the potential for ground based delivery robots. There is also excitement about drone (UAV/quadcopter) based delivery. We’ve seen many proposed projects, including Amazon prime Air and much debate. Many years ago I also was perhaps the first to propose that drones deliver a defibrillator anywhere and there are a few projects underway to do this.
Some of my students in the Singularity University Graduate Studies Program in 2011 really caught the bug, and their team project turned into Matternet — a company with a focus in drone delivery in the parts of the world without reliable road infrastructure. Example applications including moving lightweight items like medicines and test samples between remote clinics and eventually much more.
I’m pleased to say they just announced moving to a production phase called Matternet One. Feel free to check it out.
When it comes to ground robots and autonomous flying vehicles, there are a number of different trade-offs:
- Drones will be much faster, and have an easier time getting roughly to a location. It’s a much easier problem to solve. No traffic, and travel mostly as the crow flies.
- Deliverbots will be able to handle much heavier and larger cargo, consuming a lot less energy in most cases. Though drones able to move 40kg are already out there.
- Regulations stand in the way of both vehicles, but current proposed FAA regulations would completely prohibit the drones, at least for now.
- Landing a drone in a random place is very hard. Some drone plans avoid that by lowering the cargo on a tether and releasing the tether.
- Driving to a doorway or even gate is not super easy either, though.
- Heavy drones falling on people or property are an issue that scares people, but they are also scared of robots on roads and sidewalks.
- Drones probably cost more but can do more deliveries per hour.
- Drones don’t have good systems in place to avoid collisions with other drones. Deliverbots won’t go that fast and so can stop quickly for obstacles seen with short range sensors.
- Deliverbots have to not hit cars or pedestrians. Really not hit them.
- Deliverbots might be subject to piracy (people stealing them) and drones may have people shoot at them.
- Drones may be noisy (this is yet to be seen) particularly if they have heavier cargo.
- Drones can go where their are no roads or paths. For ground robots, you need legs like the BigDog.
- Winds and rain will cause problems for drones. Deliverbots will be more robust against these, but may have trouble on snow and ice.
In the long run, I think we’ll see drones for urgent, light cargo and deliverbots for the rest, along with real trucks for the few large and heavy things we need.
Submitted by brad on Sat, 2015-02-28 14:20.
I was recently considering the price of UberX in Los Angeles. It’s gotten disturbingly low:
Flag drop: $0 18 cents/minute 90 cents/mile
This is not a very good deal for the driver. After Uber’s 20% cut, that’s 72 cents/mile. According to AAA, a typical car costs about 60 cents/mile to operate, not including parking. (Some cars are a bit cheaper, including the Prius favoured by UberX drivers.) In any event, the UberX driver is not making much money on their car.
The 18 cents/minute — $10.80 per hour, drops to only $8.64/hour while driving. Not that much above minimum wage. And I’m not counting the time spent waiting and driving to and from rides, nor the miles, which is odd that the flag drop fee. There is a $1 “safe rides fee” that Uber pockets (they are being sued over that.) And there is a $4 minimum, which will hit you on rides of up to about 2.5 miles.
So Uber drivers aren’t getting paid that well — not big news — but a bigger thing is the comparison of this with private car ownership.
As noted, private car ownership is typically around 60 cents/mile. The Uber ride then, is only 50% more per mile. You pay the driver a low rate to drive you, but in return, you get that back as free time in which you can work, or socialize on your phone, or relax and read or watch movies. For a large number of people who value their time much more than $10/hour, it’s a no-brainer win.
The average car trip for urbanites is 8.5 miles — though that of course is biased up by long road trips that would never be done in something like Uber. I will make a guess and drop urban trips to 6.
The Uber and private car costs do have some complications:
* That Safe Rides Fee adds $1/trip, or about 16 cents/mile on a 6 mile trip
* The minimum fee is a minor penalty from 2 to 2.5 miles, a serious penalty on 1 mile trips
* Uber has surge pricing some of the time that can double or even triple this price
As UberX prices drop this much, we should start seeing people deliberately dropping cars for Uber, just as I have predicted for robocars. I forecast robotaxi service can be available for even less. 60 cents/mile with no cost for a driver and minimal flag drop or minimum fees. In other words, beating the cost of private car ownership and offering free time while riding. UberX is not as good as this, but for people of a certain income level who value their own time, it should already be beating the private car.
We should definitely see 2 car families dropping down to 1 car plus digital rides. The longer trips can be well handled by services like Zipcar or even better, Car2Go or DriveNow which are one way.
The surge pricing is a barrier. One easy solution would be for a company like Uber to make an offer: “If you ride more than 4,000 miles/year with us, then no surge pricing for you.” Or whatever deal of that sort can make economic sense. Sort of frequent rider loyalty miles. (Surprised none of the companies have thought about loyalty programs yet.)
Another option that might make sense in car replacement is an electric scooter for trips under 2 miles, UberX like service for 2 to 30 miles, and car rental/carshare for trips over 30 miles.
If we don’t start seeing this happen, it might tell us that robocars may have a larger hurdle in getting people to give up a car for them than predicted. On the other hand, some people will actually much prefer the silence of a robocar to having to interact with a human driver — sometimes you are not in the mood for it. In addition, Americans at least are not quite used to the idea of having a driver all the time. Even billionaires I know don’t have a personal chauffeur, in spite of the obvious utility of it for people whose time is that valuable. On the other hand, having a robocar will not seem so ostentatious.
Submitted by brad on Tue, 2015-02-10 16:43.
Electric Vehicles are moving up, at least here in California, and it’s gotten to the point that EV drivers are finding all the charging stations where they want to go already in use, forcing them to travel well outside their way, or to panic. Sometimes not charging is not an option. Sometimes the car taking the spot is already mostly charged or doesn’t need the charge much, but the owner has not come back.
Here in Silicon Valley, there is a problem that the bulk of the EVs have 60 to 80 miles of range — OK for wandering around the valley, but not quite enough for a trip to San Francisco and back, at least not a comfortable one. And we do like to go to San Francisco. The natives up there don’t really need the chargers in a typical day, but the visitors do. In general, unless you are certain you are going to get a charger, you won’t want to go in a typical EV. Sure, a Tesla has no problem, but a Tesla has a ridiculous amount of battery in it. You spend $40,000 on the battery pack in the Tesla, but use the second half of its capacity extremely rarely — it’s not cost effective outside the luxury market, at least at today’s prices (and also because of the weight.)
Charging stations are somewhat expensive. Even home stations cost from $400 to $800 because they must now include EVSE protocol equipment. This does a digital negotiation between the car and the plug on how much power is available and when to send it. The car must not draw more current than the circuit can handle, and you want the lines to not be live until the connection is solid. For now that’s expensive (presumably because of the high current switching gear.) Public charging stations also need a way to doing billing and access control.
Another limit on public charging stations, however, is the size of the electrical service. A typical car wants 30 amps, or up to 50 if you can get it. Put in more than a few of those and you’re talking an upgrade to the building’s electrical service in many cases.
I propose a public charging pole which has 4 or even 8 cords on it. This pole would be placed at the intersection of 4 parking spots in a parking lot. (That’s not very usual, more often they end up placed against a wall, with only 2 parking spots in range, because that’s where the power is.) The station, however, may not have enough power to charge all the cables at once. read more »
Submitted by brad on Wed, 2015-01-28 14:48.
Uber’s gotten a lot of bad press over its surge pricing system. As prices soared during Storm Sandy and a hostage crisis in Sydney, people saw it as price gouging when times are tough.
I’ve always thought the public reaction to price gouging in times of scarcity and emergency was irrational. While charging double or triple for food, rides or generators does mean that the rich get more access to them, it also does at least a partial job of assuring that people who truly need or want things the most get access over those who need them less. I do not quite understand why the alternative — keeping prices flat, and allocating items to whoever gets there first — is so broadly preferred.
Uber has promoted another reason to have surge pricing. They argue that as they raise the prices, it causes an increase in supply. Unlike generators, where there are only so many in the stores during a storm, doubling the price of a ride can mean a sudden influx of rides, both from people in the area and even those who rush in from outside to make the extra buck. I suspect that does happen, but Uber also makes more money and poorer people are priced out of the market, which has been a PR nightmare.
For the recent snowstorm that didn’t end up being too bad in NY, Uber announced some new policies — a cap of 2.8x on the price increase, and donation of all proceeds to the Red Cross. The mayor of New York even declared the surge-pricing was illegal.
It’s an interesting start, but what do they mean by all proceeds? If they’re not increasing the income of the drivers — many of whom are low enough income that the double-time or more rates can make a real difference — then they are defeating the whole point of this.
Here are some potential ideas I was thinking about for how to play surge pricing:
- Keep Uber’s fee during a surge the same. Ie. it’s always 20% of the rack rate, not of the surged price. So Uber is making no extra money (except from the extra volume,) just the drivers.
- To get really extreme, Uber could reduce its cut as volume increases, so they don’t even make money from the increased volume.
- They could just donate all their cut (which may be what they mean when they say all proceeds.)
- The extra could be split between drivers and a charity. You get more drivers, and they make more, but good deeds are also done.
Another option would be to do something like a “buy one give one” as we’ve seen in physical products. This would mean that during the surge, riders could elect to pay more to get priority (and to attract drivers.) But if the surge is for 2x, they might pay 3x, and the overage would go to provide a regular priced ride (1x) for somebody else, while still paying the driver 2x.
The tricky part is how to make sure the subsidized rides only go to those who can’t afford to pay the surge price. The subsidized rides will presumably still be in short supply. You want them to go only to those who truly need them. Options might include:
- Offer subsidies primarily for those who use UberX almost exclusively. Use a lot of black car and you don’t get a subsidy. (Yes, some people use black car on expense account and UberX on personal rides, including myself, so this is not perfect.)
- Require a declaration of low income. Subject those who declare low income to random audits after the fact, pulling up credit scores or asking them to actually demonstrate the low income. If they lied, charge them the full amount plus a penalty for all subsidized rides they took.
- Drivers could also elect to subsidize, and say they will drive for 1x, or any other amount, to really increase the supply of subsidized rides and the amount of subsidy. They might get a tax donation receipt for doing so if Uber could set up the tax structures properly with a non-profit. (A non-profit would probably need to work over all companies or be fully independent of the company.)
As already happens with the surge system, adjust the surcharge and subsidy to try and make demand match supply.
You could even offer rides to those in need for 0.5x, a flat fee, or even nothing, though nothing is very easy to abuse.
Submitted by brad on Tue, 2014-12-16 01:07.
Uber is spreading fast, and running into protests from the industries it threatens, and in many places, the law has responded and banned, fined or restricted the service. I’m curious what its battles might teach us about the future battles of robocars.
Taxi service has a history of very heavy regulation, including government control of fares, and quota/monopolies on the number of cabs. Often these regulations apply mostly to “official taxis” which are the only vehicles allowed to pick up somebody hailing a cab on the street, but they can also apply to “car services” which you phone for a pick-up. In addition, there’s lots of regulation at airports, including requirements to pay extra fees or get a special licence to pick people up, or even drop them off at the airport.
Why we have Taxi regulation and monopolies
The heavy regulation had a few justifications:
- When hailing a cab, you can’t do competitive shopping very easily. You take the first cab to come along. As such there is not a traditional market.
- Cab oversupply can cause congestion
- Cab oversupply can drive the cost of a taxi so low the drivers don’t make a living wage.
- We want to assure public safety for the passengers, and driving safety for the drivers.
- A means, in some places, to raise tax revenue, especially taxing tourists.
Most of these needs are eliminated when you summon from an app on your phone. You can choose from several competing companies, and even among their drivers, with no market failure. Cabs don’t cruise looking for fares so they won’t cause much congestion. Drivers and companies can have reputations and safety records that you can look up, as well as safety certifications. The only remaining public interest is the question of a living wage.
Taxi regulations sometimes get stranger. In New York (the world’s #1 taxi city) you must have one of the 12,000 “medallions” to operate a taxi. These medallions over time grew to cost well north of $1 million each, and were owned by cab companies and rich investors. Ordinary cabbies just rented the medallions by the hour. To avoid this, San Francisco made rules insisting a large fraction of the cabs be owned by their drivers, and that no contractual relationship could exist between the driver and any taxi company.
This created the situation which led to Uber. In San Francisco, the “no contract” rule meant if you phoned a dispatcher for a cab, they had no legal power to make it happen. They could just pass along your desire to the cabbie. If the driver saw somebody else with their arm up on the way to get you, well, a bird in the hand is worth two in the bush, and 50% of the time you called for a cab, nobody showed up!
Uber came into that situation using limos, and if you summoned one you were sure to get one, even if it was more expensive than a cab. Today, that’s only part of the value around the world but crazy regulations prompted its birth.
The legal battles (mostly for Uber)
I’m going to call all these services (Uber, Lyft, Sidecar and to some extent Hail-O) “Online Ride” services. read more »
Submitted by brad on Sun, 2014-10-26 14:22.
A recent newspaper column where people complained about carpool cheats got me thinking — could cheating actually be a solution to some carpool problems?
For many years, the wisdom was that carpool lanes were helping traffic and the environment, but that wisdom has been changing, and it is now seen that the lanes actually hurt (at least the traffic) in many cases. As such, the new approach is to build “managed lanes” and in particular the High-Occupancy-Toll (HOT) lanes which let solo drivers pay to use the lane. In addition, low emission cars and motorcycles usually get to use the lanes solo.
Why does this help? It turns out that a typical configuration of 3 solo lanes and one carpool lane is performing badly when the carpool lane is well under capacity. The ideal road would have all 4 lanes running just under 100% capacity (which is around 2,000 cars per hour, or 8,000 for the whole road.) At rush hour, however, the lanes often collapse in congestion to stop and go, which can drop as low as 1,300 vehicles/hour.
Carpool approaches suggest that if you have one carpool lane running at less than capacity (and thus congestion free and highly attractive) that you will make people choose to carpool. Each carpool takes a car or two off the road, which is a win for congestion (and the environment.)
Consider one carpool situation, where the carpool lane is running free at 50% of capacity, and the other 3 lanes are at 100% of capacity. You’re now moving 7,000 vehicles/hour instead of 8,000, but that would be OK if it’s because you took more than 1,000
vehicles off the road.
Unfortunately that’s not even remotely true. The vast majority of the carpools on the road are natural carpools that would have happened anyway. Couples or families travelling together. “Kidpools” where in almost all cases no car was taken off the road. The permitted solo drivers in low emission vehicles and motorcycles don’t remove cars, but are greener. The number of “induced” carpools — carpools that were created because of the attractive travel time offered by the carpool lane — is quite low. Perhaps as low as 10%, but likely not more than 20%. HOV-3 lanes may have more induced carpools.
To make it worse, consider a carpool lane at 70% usage (good) but the 3 other lanes in congestion, and now getting 1,500 vehicles per hour. We’ve dropped our road to just 5,900 cars per hour. And at 20% induced carpools we only took 280 cars off the road, for a total of 6,180 instead of our ideal of 8,000. There is a zone of congestion where moving another 500 cars from the solo lanes to the carpool lane would relieve the congestion in the solos, and we would get closer to our 8,000.
That’s what HOT lanes are about. By charging a fee, they move solo drivers who are willing to pay to use the underutilized carpool lane, and we remove them from the solos, increasing their throughput as well. It’s a win-win-win. HOT lanes adjust the price — if the carpool lane is starting to fill up, the price jacks up. The goal is to keep the carpool lane enough below 100% capacity that it flows smoothly, which is good for flow and also what makes it attractive in the first place to make those induced carpools.
With HOT, you can have 1,000 carpoolers and 900 paying solos and also 200 induced carpools so the lane is now delivering the equivalent of 2,100 vehicles/hour and everybody wins. Letting efficient solos use the lane doesn’t involve money, but subsidizes efficient vehicles.
Without HOT, the bizarre conclusion is that cheaters are helping move traffic along. Cheaters only cheat when the carpool lane is going really well — ie. underutilized — and the solo lanes are getting congested. Cheaters take some load off the solo lanes and make use of the wasted capacity. They will not cheat if the carpool lane is not beating the solo lanes by a nice margin. If the carpool lane gets overloaded, they are going to leave it — why risk the ticket?
I should note that I have never, ever deliberately cheated in the carpool lane. (Like most, once or twice I have forgotten what time it was for a minute or two.) I am not trying to justify cheating, and in fact one concern is that some cheaters will read this and imagine they are doing a service. Cheaters are helping the system, but in a completely unfair and inappropriate way.
One reason we don’t have more HOT lanes, now that people realize that they are better, is that it costs a lot of money to put them in. Part of that money is for infrastructure — gantries, transponders, signs with prices, enforcement teams, operations teams. The biggest cost comes from the fact that generally people like to make HOT lanes truly separate from the main lanes, with a double line, and entry/exit only allowed at certain points. That means restriping or even new construction.
Many of the world’s transit systems work on an honour system. You have to buy a ticket, but nothing checks this. Instead, if you are caught on board without a ticket, you pay a fat fine. The fine is often calculated to balance the enforcement level, so that a regular cheater will be caught enough that it’s more expensive to cheat than to buy tickets. But often not a lot more expensive, as it turns out.
What if HOT lanes were the same way? Go ahead and cheat! Install random enforcement stations with cameras, and enforce enough so that any regular “cheater” gets fines which are calculated to collect as much or more money than the tolls.
The obvious flaw here is that this only works for the regular cheater. It’s too random, and an occasional lane user (or tourist) would be taking a big gamble, without enough use to balance it out. So we can add payment by cell phone to even things out.
Before leaving, or after arriving, tell your phone or browser you will be using or did use the lane. (The reason to do it in advance is
you will get a better price.) Your phone can show you the price, and some road signs will display it as well. This gives you a token which includes the time and your licence plate. If you get a fine notice, you can nullify it by providing the token.
(If you don’t care about privacy, you could register the licence plate directly. But I do care about privacy.)
This works with minimal new infrastructure. And payment via phone would be set to be cheaper than the average payment you would pay through random fines, so most people would do it. And all this happens with minimal new infrastructure, as long as you don’t need to reconfigure the lanes.
Enforcement can involve cameras, which may or may not be recording. You need enough of them so that people don’t just briefly switch out of the carpool lane just before coming to a camera, so this has some infrastructure cost. The camera would record the photo of the front seats of your car, and your plate. In isolate carpool lanes this does work better.
This is aimed at places where 2 is a carpool. It means something controversial. Carpoolers must share the front seat. And that means no kidpooling with children small enough to be required to ride in the back seat. Some people will hate that (parents) and some will love it (those who feel that kidpooling is unfair because it almost never causes an induced carpool.) This controversy can be some what mitigated by offering a discount to people who declare they are kidpooling (or better, multi-family kidpooling) with occasional checks.
It’s also an issue for Taxis, Uber and people with chauffeurs. Forcing the latter to pay won’t bother many people. Taxis can be given special status. Ad-hoc taxis, like Uber, can be told, “hey, just make the ride in the front if you want a free entry.” Is that such a big burden? If so, alternate systems can be set up, including requesting a token over the smartphone which can be compared to audited records of fares.
The camera stations could also photograph in through the sides of vehicles. Tinted side windows would not get to be carpools. This is harder than just doing the front, and harder to hide. And there would still be occasional live human observers, to the extent that cost allows.
To avoid risk of people wanting to use phones while driving, we simply allow you to buy a retroactive token within a day of your trip. (You don’t learn about your fine for a couple of days.) You could do that on the web, on a smartphone, by text (retroactive only) or even at any convenience store or gas station that has a payment machine. (This idea is not new. A decade ago I drove a toll road in Melbourne which lets you buy a toll pass at a gas station after you drive the road.)
Or, of course, just pay the fines if they are not that much more expensive, on average than buying tokens.
Even carpoolers could register that they carpooled, in case a problem comes up. Users will want to register an e-mail address or app address with the system under their plate to get notices of fines. If you don’t, notices would come by postal mail. If somebody else registers your plate and you don’t, it might delay notice of fines but you would fix this after the first one.
If the typical toll is $3, and the fine is $300, you probably would get a fine notice you need to nullify perhaps every 75 uses on average. This makes paying cheaper. The smartphone app would also notice when you travel the route and remind you.
To protect privacy, the system would not remember tokens it issues, and it would erase all images once it was confirmed the car was legit (carpool, allowed vehicle or had a token.) Only the images of non-carpools who did not respond with their token would be retained for issuing fines to their car.
There can be problems with photo enforcement if it is dark (as it is during winter for portions of rush hour) or in places where the sun is at just the wrong angle. The latter can be fixed because we know just where the sun will be. The former is more challenging. Cameras would need to be placed in line with suitable street lights, and have larger lenses. During the day used cell phones in rainproof cases with tiny solar panels could do the job at low cost.
Submitted by brad on Tue, 2014-02-04 10:54.
Very long-time readers of this blog will remember a proposal I made 10 years ago that cruise ship inside cabins use HDTVs with the outside view. Now a cruise ship is launching with such a system, though bigger than I proposed.
The Royal Caribbean vessel will feature an artificial balcony using an 80 inch screen including a fake railing. While the cameras used are 4K, I suspect the screens will only be HDTV, since 4K 80 inch screens are hugely expensive right now, though very shortly they will be quite affordable for this.
It will be interesting to see if the virtual balcony approach does much better than just using something meant to look like a window, which frankly would be a bunch easier though not get that 3D effect from the railing. (The fact that the image and railing are at the same focus distance may actually complicate things.)
I think an interesting approach would be instead to use a screen with infinity optics, which make the screen focus as though it is at infinity. This requires space outside the room, which you could get by having two adjoining cabins each take a box out of the other cabin for the mirror and lenses. (Though doing really good collimated light takes a lot of space which is at too much of a premium in a cruise ship, though perhaps not as much in interior cabins.
The sample photo shows a rather large stateroom — usually interior rooms are small and for those who can’t afford a window, but this might change. One reason people tolerate interior rooms is they plan to spend very little time in the room not sleeping, but the reality is that even doing that, it is disconcerting not to have the subtle cues of real exposure to day and night, waking up and not knowing what time it is. It generates a greater feeling of being closed in to be in a small enclosed and windowless space, compared to large interior spaces. As I pointed out before, having a view of the real horizon helps a lot with seasickness.
If this is a success, it could lead to several things:
- Ability to sell many more interior rooms, making better use of space in the middle of the very wide ships desired today.
- Low, central cabins have the least sway, but in the past were not popular with the seasick because that’s much worse without a window.
- People might actually choose a larger, interior cabin at the same price as a much smaller, exterior cabin. Even if you plan to spend only modest time awake in your cabin, life in a larger cabin is more pleasant.
- Virtual walls could be put on multiple sides of the cabin, so you get the illusion of an owner’s suite, with views in all directions.
To really get a super effect, you could even have people wear 3D glasses in the cabin — polarized ones that double as sunglasses if you can make the screens bright enough. These allow you to do a special trick if there is only one person in the room, which make the screens simulate parallax, so that as you move your head, the background moves as though you are really looking through a window. Most ocean scenes are not very 3D themselves. It is debatable if this would be good enough for people to find it worth wearing the glasses, and of course there is the issue of dealing with only one person in the room. You can handle 2 people in the room if you have shutter glasses, very bright screens, and 240hz or faster displays. Handling 2 is probably enough — turn the effect off the very rare times you have guests.
Finally, I would even wonder if it made sense to pipe in outside air on demand.
4K displays can get close to eye resolution depending on the viewing distance. Interior cabins on cruise ships are dismal places, and so if this can make them more palatable, it can be financially worthwhile.
Disney has also been doing this since 2010, I have learned, with a virtual porthole. They also add animations to the video (of Disney Characters peeking in the window) which presumably the kids like. Reports are this has caused a major boost in their inside cabin sales.
Submitted by brad on Fri, 2014-01-03 21:33.
A big story this Christmas was a huge surge in the use of rush shipping in the last 2 days before Christmas. Huge numbers of people signed up for Amazon Prime, and other merchants started discounting 2 day and overnight shipping to get those last minute sales. In turn, a lot of stuff didn’t get delivered on time, making angry customers and offers of apology discounts from merchants. This was characterized as a “first world problem” by many outside the game, of course.
When I shop, I am usually travelling outside the US and so I have to get stuff even before the 24th, and I’ve had stuff I left to the last day not delivered several times, so I know to avoid doing it. Some packages are not going to make it, and this should be expected — even desired.
While it makes sense to increase the infrastructure a bit as online shopping grows in popularity, you don’t want to go nuts at Christmas. If you need to build your infrastructure to handle every Christmas gift, you have to build it too big, and you pay for that through higher prices the rest of the year. Shippers need to figure out their real capacity, and everybody needs to plan based on it.
The failure this season was not a failure of the delivery system. Rather it was a failure of either the shippers to tell the merchants what their capacity was, and/or a failure of the merchants to communicate to customers that too much was being shipped and not everybody could be promised Dec 24 delivery.
The obvious way to fix this is first to have the shippers get a solid handle on their capacity for the various types of shipping to the various destinations. They can also identify the bottlenecks and widen them a modest amount.
The next thing is for the merchants to know just how much shipping they can buy. There can either be a live spot market — so the merchant web sites just stop offering the delivery promise when the capacity is reached, or merchants could even attempt to pre-contract for capacity, paying for it whether they need it or not (or reselling it if they know they won’t need it.) Merchants should be building their own forecasts about available capacity and querying shippers for updates on just how much more is left. Capacity isn’t a fixed thing — it depends on the size of packages and where they are going and many other things — but this is a problem computers can handle.
Finally, the shippers and the merchants can start increasing the price of the rush shipping so that demand and supply match. This can be based on accurate forecasts, or just live data. As Dec 23rd wears on, the price of next-day shipping will keep going up and up so only the serious buy it. Of course, this might reveal just how keen some people are to get items, and justify having more capacity in years to come. Indeed, as the price goes up, it may make sense for Amazon to say, “Listen, we’re just going to buy this for you at your local Wal-Mart, it will be waiting for you there.” Wal-Mart surely won’t mind that.
There are also some tricks to increase capacity. For example, most people would probably tolerate having to pick up items at a retail location — FedEx and UPS and the USPS of course have tons of those — especially if it is the only option or offers a serious discount over surge priced home delivery. (This is not as good for sending gifts to remote locations.) Temporarily contracted depots could also be used. You want to streamline these depots, as lots of people will be coming in, so you want some nice system where people bring in a bar code and everything is optimized to get them out the door with the right package quickly.
All of this will push people to shop and ship a little earlier, smoothing out the rush, and avoiding having to design the system for one peak day. I have always found it remarkable that most stores and malls have giant parking lots (back in the brick and mortar world) which are only filled in December. It’s such a waste — but something robocars will fix in the future.
Delivery to the wrong address
I had a missed delivery myself this year. In this case it was on December 14th because I went home early, and I had the gifts arriving 2 days before I left. But oddly, I got the note that the package had been delivered at 6pm — but it wasn’t. Both UPS and Amazon had very little set up to handle this. Amazon’s system insists you wait at least a day to complain about this, which was no help to me. I could have used that day to replace the items if I were sure it wasn’t coming.
After I left, the package showed up on my porch on Sunday. UPS does not operate Sunday so it seems pretty likely they had left the package with a neighbour who was perhaps away for a few days. I presume the neighbour eventually came and dropped off the package but they left no note. (Of course I wish they had done it right away — replacing the gifts in Canada cost me a bunch extra.)
Amazon had already given a refund — fairly good service there — and so I just had UPS return the package as undelivered which costs me nothing, so that all worked out, except the scramble and the extra cost of replacing the items.
I don’t know how often this happens — it’s in the Amazon FAQ so it must be often enough — but there are some obvious fixes. The UPS driver’s wand, which scans the package on delivery, should record more data, including any location from a GPS in the wand or the truck, but perhaps more easily the MACs and signal strengths of any WIFI nodes visible when the package was scanned.
That information would have both allowed UPS to say, “OK, that’s odd, this doesn’t match where the package should be going” right when it was scanned, or it would have allowed me to figure out where it went and get it right away.
You’re probably wondering, didn’t I just imagine it was stolen? I did consider that possible, though in my safe neighbourhood it doesn’t appear to be a real danger. Somebody following UPS trucks at Christmas time to steal gifts would be very Grinchey, not to say it doesn’t happen. In safe neighbourhoods, UPS and Fedex routinely just leave packages at the door. Not actually signed for, I presume they just eat the loss the rare times they are stolen, or perhaps the merchant does. It’s small enough shrinkage that the system handles it.
Submitted by brad on Sun, 2013-09-15 15:22.
Over the years, particularly after Burning Man, I’ve written posts about how RVs can be improved. This year I did not use an regular RV but rather a pop-up camping trailer. However, I thought it was a good time to summarize a variety of the features I think should be in every RV of the future.
We keep talking about smart power and smart grids but power is expensive and complex when camping, and RVs are a great place for new technologies to develop.
To begin with, an RV power system should integrate the deep cycle house batteries, a special generator/inverter system, smart appliances and even the main truck engine where possible.
Today the best small generators are inverter based. Rather than generating AC directly from an 1800rpm motor and alternator, they have a variable speed engine and produce the AC via an inverter. These are smaller, more efficient, lighter and quieter than older generators, and produce cleaner power. Today they are more expensive, but not more expensive than most RV generators. RV generators are usually sized at 3,600 to 4,000 watts in ordinary RVs — that size dictated by the spike of starting up the air conditioner compressor when something else, like the microwave is running.
An inverter based generator combined with the RV’s battery bank doesn’t have to be that large. It can draw power for the surge of starting a motor from the battery. The ability to sustain 2,000 watts is probably enough, with a few other tricks. Indeed, it can provide a lot of power even with the generator off, though the generator should auto-start if the AC is to be used, or the microwave will be used for a long time.
By adding a data network, one can be much more efficient with power. For example, the microwave could just turn off briefly when the thermostat wants to start the AC’s compressor, or even the fans. The microwave could also know if it’s been told to cook for 30 seconds (no need to run generator) or 10 minutes (might want to start it.) It could also start the generator in advance of cooling need.
If the master computer has access to weather data, it could even decide what future power needs for heating fans and air conditioning will be, and run the generator appropriately. With a GPS database, it could even know the quiet times of the campsite it’s in and respect them.
A modern RV should have all-LED lighting. Power use is so low on those that the lights become a blip in power planning. Only the microwave, AC and furnace fan would make a difference. Likewise today’s TVs, laptops and media players which all draw very few watts.
A smart power system could even help plugging into shore power, particularly a standard 15a circuit. Such circuits are not enough to start many ACs, or to run the AC with anything else. With surge backup from the battery, an RV could plug into an ordinary plug and act almost like it had a high power connection.
To go further, for group camping, RVs should have the ability to form an ad-hoc power grid. This same ability is already desired in the off-grid world, so it need not be developed just for RVs. RVs able to take all sorts of input power could also eventually get smart power from RV campsites. After negotiation, a campsite might offer 500v DC at 12 amps instead of 115v AC, allowing the largest dual-AC RVs to plug into small wires. read more »
Submitted by brad on Tue, 2013-07-02 10:42.
BART, one of the SF Bay Area’s transit systems, is on strike today, and people are scrambling for alternatives. The various new car-based transportation companies like Uber, Lyft and Sidecar are all trying to bump their service to help with the demand, but in the future I think there will be a much bigger opportunity for these companies.
The average car has 1.47 people in it, and the number is less on urban commutes. Since most cars hold 4-5 people, the packed roads have a huge amount of excess capacity in empty seats. While Lyft and Sidecar call themselves ridesharing companies, they are really clever hacks at providing taxi service. Lyft’s original product, Zimride, is more ridesharing but aimed at the long-distance market. Many companies have tried to coordinate true ridesharing for commuters and people in a city, but with only limited success.
A transit strike offers an interesting opportunity. Without commenting on the merits of the sides in the strike, the reality is that we can do much better with the empty seat resource than we do, and a transit strike can prompt that.
Of course, the strike is already naturally increasing carpooling, and casual carpooling (also known as slugging) also gets a large boost. In the Bay Area, things are complicated because BART is the main alternative to the Bay Bridge, and that bridge is going to get very heavily loaded. Ferry service is increasing but it’s still a 25 minute trip every 45 minutes from the various Ferry docks. The bridge and highways are increasing incentives for HOV-3+ carpools.
Casual carpooling tends to only get you to a rough area near your destination. In this case that may be OK, as other transit is still running, only BART is out. At the semi-official casual carpool stations, there are signed waiting places that get long lines for all the general destinations. You take what you can get, and it’s also efficient in moving cars in and out.
Computer assisted carpooling could schedule people together who are both starting and ending their trip fairly close together, for maximum convenience and efficiency. If the trip starts at people’s houses, or some common point, you don’t have the casual carpool concentration issue. If you start from stops of the transit lines which are running, you still have a problem.
Because of the load on the bridge, the ferry seems attractive, though there you have a chokepoint, particularly in picking up people from the boat. To do that, you would need a parking lot with numbered spaces. People allocated to a car because of a common destination would be given a spot number, and walk to the car there as they get off the ferry. A simple curb (which suffices for casual carpools) would not be enough.
Companies like Lyft and Sidecar make use of people who want to become part-time taxi drivers. While they pretend (for legal reasons) that they are people who were “already going that way” who take along others for a donation, that fiction could become reality in a transit strike. Most carpoolers would probably take along extras for no money, or gas money, especially when they gain a special carpool lane or toll saving as they do on the Bay Bridge. There would also be value in Jitney service, where a “professional” driver (who is just driving for the money, officially or not) takes 3-4 passengers along the common route, and they all pay a reasonable share.
Within a city, that share could be competitive, even with the subsidized cost of transit, which tends to be close to $2/ride. Taxi fares are $2.50/mile plus a flag drop, which means a trip of 3-4 miles could be competitive if split among 4 people, and not that bad (considering the higher level of service) even on trips that are twice as long. (The Bay Bridge is 10 miles long so taxi fares will have a hard time competing with even the higher BART fare.)
Jitney service (shared door to door or on-demand fixed route) is quite popular outside the USA, and indeed there are many cities with active private transit systems and jitney systems. But most Americans are not interest in the inconvenience of going slightly out of their way to deal with the needs of other passengers, and so attempts at such rideshare here don’t rule the world. It’s probably too late for this strike, but the next transit strike might end up demonstrating there are other systems aside from transit that are efficient and cost-effective.
The interface would not be too different from existing systems, except people would specify how much inconvenience they would tolerate from having others in the vehicle and going out of their way, in exchange for savings.
When it comes to robocars, this might happen as well, and it could even happen with vans to provide a very effective shared system that still offers door-to-door. Robocars also offer the potential for mixed-mode vanpool trips. In such a trip, a single person robocar takes you to a parking lot, where 12 other people all arrive within the same minute and you call get into a van. The van does the bulk of the trip, and stops near your set of destinations in a parking lot where a set of small single-person robocars sit waiting to take people the last mile. This highly efficient mode should be able to beat any existing transit because of its flexibility and door-to-door service. The vans offer the ability to be luxury vans, with business class seats with privacy screens, so that upscale transit is also possible.
Submitted by brad on Mon, 2013-05-20 13:12.
There are a growing number of apps designed to help people find parking, and even reserve and pay for parking in advance. Some know the state of lots. These apps are good for the user but also can produce a public good by reducing the number of people circling looking for parking. Studies suggest in certain circumstances a large fraction of the cars on the road are doing that.
This weekend, I attended the Maker Faire. I’ve been to almost every Make Faire, including the first, and now it’s grown to be far too successful — you can hardly walk down the aisles at the busy times. They need more space and a way to put more of it outside so thin out the crowds. Still, it is one of those places that makes you feel very clearly you are in the 21st century.
Early on Maker Faire realized it had a parking problem. The lot at the fairgrounds fills up now even before the event opens, and they manage various satellite lots and run shuttle buses to them.
This year they tried something interesting, a twitter feed with parking updates. They tweeted when lots filled up or re-opened, and suggested where to go. They took some limited feedback about lack of shuttles. I think that it by and large worked and reduced traffic around the event.
However, my judgment is that they were not entirely honest in their tweets. This year, and in prior years, they strongly encouraged people to go to one of the most remote lots, regularly telling people it was the fastest route to the event. This was not true. I don’t want to ascribe any particular malice here, but there is a suspicion that there is a temptation to make reports in the interest of the event rather than the user. This does have positives, in that cars diverted from near the event reduce traffic which makes the shuttle buses run much faster, but if you give wrong information (deliberately or by accident) this means people stop trusting it and you get the traffic back as more people ignore it.
For example, we stopped at a remote lot, and saw a very long shuttle line. We drove on to a closer lot (also reported as having spaces, but not reported as clearly a better choice) to find lots of spaces, no shuttle line, frequent shuttles and also a walk that was only slightly longer than the shuttle trip. read more »
Submitted by brad on Thu, 2013-03-21 22:37.
Earlier in part one I examined why it’s hard to make a networked technology based on random encounters. In part two I explored how V2V might be better achieved by doing things phone-to-phone.
For this third part of the series on connected cars and V2V I want to look at the potential for broadcast data and other wide area networking.
Today, the main thing that “connected car” means in reality is cell phone connectivity. That began with “telematics” — systems such as OnStar but has grown to using data networks to provide apps in cars. The ITS community hoped that DSRC would provide data service to cars, and this would be one reason for people to deploy it, but the cellular networks took that over very quickly. Unlike DSRC which is, as the name says, short range, the longer range of cellular data means you are connected most of the time, and all of the time in some places, and people will accept nothing less.
I believe there is a potential niche for broadcast data to mobile devices and cars. This would be a high-power shared channel. One obvious way to implement it would be to use a spare TV channel, and use the new ATSC-M/H mobile standard. ATSC provides about 19 megabits. Because TV channels can be broadcast with very high power transmitters, they reach almost everywhere in a large region around the transmitter. For broadcast data, that’s good.
Today we use the broadcast spectrum for radio and TV. Turns out that this makes sense for very popular items, but it’s a waste for homes, and largely a waste for music — people are quite satisfied instead with getting music and podcasts that are pre-downloaded when their device is connected to wifi or cellular. The amount of data we need live is pretty small — generally news, traffic and sports. (Call in talk shows need to be live but their audiences are not super large.)
A nice broadcast channel could transmit a lot of interest to cars.
- Timing and phase information on all traffic signals in the broadcast zone.
- Traffic data, highly detailed
- Alerts about problems, stalled vehicles and other anomalies.
- News and other special alerts — you could fit quite a few voice-quality station streams into one 19 megabit channel.
- Differential GPS correction data, and even supplemental GPS signals.
The latency of the broadcast would be very low of course, but what about the latency of uploaded signals? This turns out to not be a problem for traffic lights because they don’t change suddenly on a few milliseconds notice, even if an emergency vehicle is sending them a command to change. If you know the signal is going to change 2 seconds in advance, you can transmit the time of the change over a long latency channel. If need be, a surprise change can even be delayed until the ACK is seen on the broadcast channel, to within certain limits. Most emergency changes have many seconds before the light needs to change.
Stalled car warnings also don’t need low latency. If a car finds itself getting stalled on the road, it can send a report of this over the cellular modem that’s already inside so many cars (or over the driver’s phone.) This may take a few seconds to get into the broadcast stream, but then it will be instantly received. A stalled car is a problem that lasts minutes, you don’t need to learn about it in the first few milliseconds.
Indeed, this approach can even be more effective. Because of the higher power of the radios involved, information can travel between vehicles in places where line of sight communications would not work, or would actually only work later than the server-relayed signal. This is even possible in the “classic” DSRC example of a car running a red light. While a line of sight communication of this is the fastest way to send it, the main time we want this is on blind corners, where LoS may have problems. This is a perfect time for those longer range, higher power communications on the longer waves.
Most phones don’t have ATSC-M/H and neither do cars. But receiver chips for this are cheap and getting cheaper, and it’s a consumer technology that would not be hard to deploy. However, this sort of broadcast standard could also be done in the cellular bands, at some cost in bandwidth for them.
19 megabits is actually a lot, and since traffic incidents and light changes are few, a fair bit of bandwidth would be left over. It could be sold to companies who want a cheaper way to update phones and cars with more proprietary data, including map changes, their own private traffic and so on. Anybody with a lot of customers might fight this more efficient. Very popular videos and audio streams for mobile devices could also use the extra bandwidth. If only a few people want something, point to point is the answer, but once something is wanted by many, broadcast can be the way to go.
What else might make sense to broadcast to cars and mobile phones in a city? While I’m not keen to take away some of the nice whitespaces, there are many places with lots of spare channels if designed correctly.
Submitted by brad on Mon, 2013-03-18 16:28.
Last week, I began in part 1 by examining the difficulty of creating a new network system in cars when you can only network with people you randomly encounter on the road. I contend that nobody has had success in making a new networked technology when faced with this hurdle.
This has been compounded by the fact that the radio spectrum at 5.9ghz which was intended for use in short range communications (DSRC) from cars is going to be instead released as unlicenced spectrum, like the WiFi bands. I think this is a very good thing for the world, since unlicenced spectrum has generated an unprecedented radio revolution and been hugely beneficial for everybody.
But surprisingly it might be something good for car communications too. The people in the ITS community certainly don’t think so. They’re shocked, and see this as a massive setback. They’ve invested huge amounts of efforts and careers into the DSRC and V2V concepts, and see it all as being taken away or seriously impeded. But here’s why it might be the best thing to ever happen to V2V.
The innovation in mobile devices and wireless protocols of the last 1-2 decades is a shining example to all technology. Compare today’s mobile handsets with 10 years ago, when the Treo was just starting to make people think about smartphones. (Go back a couple more years and there weren’t any smartphones at all.) Every year there are huge strides in hardware and software, and as a result, people are happily throwing away perfectly working phones every 2 years (or less) to get the latest, even without subsidies. Compare that to the electronics in cars. There is little in your car that wasn’t planned many years ago, and usually nothing changes over the 15-20 year life of the car. Car vendors are just now toying with the idea of field upgrades and over-the-air upgrades.
Car vendors love to sell you fancy electronics for your central column. They can get thousands of dollars for the packages — packages that often don’t do as much as a $300 phone and get obsolete quickly. But customers have had enough, and are now forcing the vendors to give up on owning that online experience in the car and ceding it to the phone. They’re even getting ready to cede their “telematics” (things like OnStar) to customer phones.
I propose this: Move all the connected car (V2V, V2I etc.) goals into the personal mobile device. Forget about the mandate in cars.
The car mandate would have started getting deployed late in this decade. And it would have been another decade before deployment got seriously useful, and another decade until deployment was over 90%. In that period, new developments would have made all the decisions of the 2010s wrong and obsolete. In that same period, personal mobile devices would have gone through a dozen complete generations of new technology. Can there be any debate about which approach would win? read more »