Humans are REALLY BAD at driving cars! They should stop and let machines do it.
Around 1.2 Million humans die every year on this planet as a result of being in or around an automobile. Allowing humans to take control of high-speed land vehicles is clearly insane. Expecting them to somehow not end up slaughtering each other is criminally naive.
Human drivers are also responsible for the congestion on our urban streets and freeways. How? Because they almost never do the thing they should do when they should do it. Large amounts of road-space-time get wasted and irretrievably lost forever by slack, sloppy driving habits. Slow-downs and back-ups are almost entirely the cumulative fault of every driver that delays acceleration until it's too late to make any difference, and delays braking until its too late to avoid a complete stop.
Human drivers also make intersections with traffic lights necessary because they are incapable of following any more efficient and intelligent kind of rule, for example ones that do not result in huge delays and backups.
But isn't that just life? Isn't traffic congestion and people getting murdered in car wrecks just a part of being urban in the Age of the Automobile? Not necessarily. I'd like to challenge that assumption and suggest that there is a better way, and one that doesn't necessarily involve massive road widening and overpass construction projects. Although, those things would definitely help and will eventually be needed. Might as well start building now 'cause it ain't going to be any cheaper in the future.
And public transportation is never going to replace the car. The bus or the train doesn't go to all the places people need to go: drop off the kids at a school, swing by a supplier's premises on the way to work, hop over to a meeting before lunch, check in on a vendor in the afternoon, pick up the kids, pick up 150 lbs of groceries (try doing even that ONE thing on the goddamn bus!) and make it home some time that very same MONTH! No, screw public transportation. It has its place, and that place is limited.
However, there is a completely different traffic paradigm I'd like you to consider. The genuine possibility of completely driverless automobiles.
What could that mean for the future of urban personal transport?
Driving machines would have far greater situational awareness, more information about the cars, obstacles and hazards in its periphery, vastly superior reaction times, zero distractions or emotional impulses, and no difficulty whatsoever following very detailed traffic control instructions. For example, "proceed at 44.32 mph and merge 7 inches behind the vehicle designated 4F56 and then accelerate within 0.7 sec to 44.34 mph."
At least not as we know them, with traffic lights and massive backups in every direction. Two major thoroughfares that intersect, if the volume is high enough, warrant an overpass with full 4-way cloverleaf interchanges. Driverless cars can negotiate narrower and tighter merge ramps, therefore future cloverleaf interchanges could be built in less space. Intersecting medium to light volume thoroughfares can do so using a "roundabout" at which there is never any need to stop at any time. As long as cars are driving and not humans.
How would this work? The same way roundabouts are used today by drivers who know the trick. If there is any visibility (MANDATORY! Are you reading this, traffic engineers?) then you watch not the other cars but the gaps between them. Time your approach to hit the gap and slide right through. Only, this doesn't work when the approaching cars are not leaving an adequate gap between them. Driverless cars would know better. By leaving the gap and allowing traffic to shoot through (think of the "figure eight" trick by groups of ice skaters), the result is everyone moves through the roundabout at pace and there is no need to tailgate in the vain hope that that will move things along faster. There will also be no slowpokes clogging up our streets with their goddamn temerity and incompetence.
No "Residual Slowing"
This refers to the phenomena of an accident on a freeway in the morning resulting in a slowdown with no apparent cause remaining at that location the rest of the day (as long as traffic volume remains above a certain threshold). It only clears once traffic becomes so light that the backup, actually a form of compressible standing shock-wave, vanishes for lack of cars. Driverless cars would be capable of clearing a backup almost instantly because an entire line of cars miles long would be capable of accelerating as one and quickly resuming normal freeway speed. Each stupid human driver delays a couple of seconds after the car ahead of them moves off, thus ensuring that the backup will remain on that stretch of road all day long.
The transition to driverless cars is already happening. There are cars on the road today that can virtually drive themselves using collision avoidance technology, safe-following-distance mode cruise control, "lane control" technology and sat-nav.
Finally, a critical number of properly-equipped cars on the road creates the opportunity for cars approaching any intersection to form a kind of ad-hoc "traffic control" network in which they collectively decide on the best way for approaching vehicles to negotiate the intersection. "Distributed Processing And Control" is already a thing in Computer Science. That means the traffic lights can be simply switched off for good.
The final stage will require, sadly, the outlawing of one of the most pleasurable things I know: Taking the wheel of a car and driving it.
But that would hopefully apply only in urban areas, where driving is actually kind of a pain in the ass to be perfectly honest. As long as I could leave the city and enjoy a good hard drive on an open road once in a while, I don't think I'd miss city driving.