As it was located near the center of the US auto industry, there was an extensive automotive program at the University of Michigan (Ann Arbor) with an assortment of guest speakers from the Big Three. I went to several presentations that made quite an impression. One of them was about self-driving cars... in 1991.
The system described then relied on sensors attached to the bottom of the vehicle. Major highways would be equipped with copper wires running down the center of each lane, which the car would track in order to correct its course. I don't recall if the wire would actively broadcast a signal or be passively detected, nor how they would avoid running into other cars. As only major highways would be thus equipped, the driver had to take over in order to exit the highway and transit surface streets.
The presenter at that time was emphatic that the technology would be deployed within 10 years, because the economics were compelling. It was provably cheaper to increase the carrying capacity of highways using this system than by adding lanes. The wires were rapidly installed by making a narrow slit down the roadway, inserting a flexible conduit, and sealing the road behind. It was the same process as was being used to run fiber optics across the nation at that time, and was well understood. The added cost to vehicles would be subsidized using money saved from highway budgets. After paying for road retrofits and vehicle subsidies, the system would still be substantially cheaper than the status quo.
Of course, no such scheme made it out of the test facilities. Twenty years later, self-driving car designs no longer rely on modifications to the roads. Now the cars have an extensive map of the expected topology and navigate by comparing what they sense with what they expect.
I think there are several lessons in this.
- Any scheme requiring massive investment in infrastructure before benefits are seen is almost certainly doomed to fail. Large changes in infrastructure can best be accomplished incrementally, where a small investment brings a small benefit and continuing investment brings more benefit. It is far better to deploy self-driving cars and map roadways one at a time, without requiring a critical mass of highways and automobiles be deployed.
- Requiring multiple investments to be made by different parties invariably leads to deadlock. Car makers wouldn't add the equipment to vehicles until there was a sufficient base of wired roads for their use. States wouldn't wire the roads until there was a sufficient population of suitable cars.
- It is easy to design something to fit the infrastructure we wish we had, rather than what we really have, without realizing it. By focussing overmuch on the end state, one ignores the difficulties in getting from here to there.
Each such lesson has been shown over and over, of course. We continue to make the last mistake all the time on the Web, designing solutions which work fine except for NAT, or HTTP proxies, or URL shorteners, or some other grungy but essential detail of how the Internet actually functions.