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Japanese robocar lanes


A study is underway in Japan to build dedicated lanes for self-driving cars.

There have been experiments with dedicated lanes in the past, including a special automated lane back in the 90s in San Diego. The problem is much easier to solve (close to trivial by today's standards) if you have a dedicated lane, but this violates the first rule of robocars in my book -- don't change the infrastructure.

Aside from the huge cost of building the dedicated lanes, once you have built a lane you now have a car which can only drive itself in that dedicated lane. That's a lot less valuable to the customer, effecitvely you are only get customers who happen to commute on that particular route, rather than being attractive to everybody. And you can't self-drive on the way to or from the highway, so it is not clear what they mean when they say the driver sets a destination, other than perhaps the planned exit.

Yes, the car is a lot cheaper but this is a false economy. Robocar sensors are very expensive today but Moore's law and volume will make them cheaper and cheaper over time. Highway lanes are not on any Moore's law curve, in fact they are getting more expensive with time. And if the lane is dedicated, that has a number of advantages, though it comes with a huge cost.

Of course, today, nobody has a robocar safe enough to sell to consumers for public streets. But I think that by the early 2020s, when this study might recommend completing a highway, the engineers would open up the new lane and find that while it's attractive for its regular nature and especially attractive if it is restricted and thus has lighter and more regular traffic, the cars are already able to drive on the regular lanes just fine.

A better proposal, once robocars start to grow in popularity, would be to open robocar lanes during rush hour, like carpool lanes. These lanes would not be anything special, though they would feature a few things to make the car's job easier, such as well maintained markings, magnets in the road if desired, no changes in signage or construction without advance notice etc. But most of all they would be restricted during rush hour so that cars could take advantage of the smooth flow and predictable times that would come with all cars being self-driving. Unless humans kept taking over the cars and braking when they got scared or wanted to look at an accident in the other lanes, these lanes would be metered and remain free of traffic jams. However, you need enough robocar flow to justify them since if you only use half the capacity of a lane it is wasteful. On the other hand, such lanes could be driven by the more common "super cruise" style cars that just do lane following and ACC.


Why not throw in robo car lanes that do things human drivers can't do. For instance robocars don't need stop lights. Robocar lanes can cross at grade and as long as the cars have sufficient spacing they can simply interleave at high speed. And they don't need bridges, they can jump over ramps. And they can coordinate with other machines. Need to get up to the overhead express lane but there's no ramp nearby? Reserve a ride on the robo-forklift up to the express lane.
Need to travel 1000 miles to a different city? Reserve a spot on the robo-air-ferry. Sure, cars are heavy things to put on an air ferry, but their batteries can be enlisted to help power the craft.

Well, I think jumping over ramps is probably a bit far in the future. I guess in theory you could program it so the landing ramp is canted just right for a smooth landing but the truth is that the occasional periods of zero G would be fun for few but disconcerting for most after a while. The same is true of the scheduled intersections. While I link to the folks who have done work there to show it's possible, the reality is that people would find it pretty scary and the safety tolerances would have to be very good, since any mechanical failures going into such an intersection could result in grave danger. Use of an elevator or forklift to get up to an elevated road is interesting but of course part of the goal is to not need so many elevated roads.

A robo air ferry makes little sense to me. Instead, have your robotic car take you onto the tarmac of the airport where you get in a vastly cheaper and more efficient passenger plane, and when it lands, sitting on the tarmac is another car which will meet your needs. Unless you are carrying a lot of cargo and could not pre-ship the cargo earlier, this is by far the best approach to air travel.

Even the strongest advocates of autonomous vehicles would be nervous about going through a scheduled intersection.

In terms of ramps the idea is so far out of left-field but I love the concept. Can't see it happening.

Off topic:
Some have suggested that Leap Motion's device, a strong Kinect competitor, can be used in . , what are your thoughts?

Ordinary camera based sensors with IR emitters tend to have problems working in sunlight. The kinect is an indoor only device, for example. I have not studied the leap motion camera.

I'm affrais you may have right about this type of camera

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