In July 1969, IEEE Spectrum published an article called The Electronic Highway, by Robert E. Fenton and Karl W. Olson, two engineers at Ohio State University who were working on ways to make vehicles operate autonomously when traveling on major highways. Nearly 50 years have passed, which is practically forever in a technological context, but what's striking about this article is how many contextual similarities there are between the past and the present.
(For more about the history of intelligent transport, make sure to read our feature on Charles Adler, who was working on intelligent traffic control systems in the 1920s.)
The specific solutions that Fenton and Olson propose are a bit outdated, of course, but the problems that they discuss and the future that they look forward to have a lot in common with those peppering current discussions on vehicle autonomy. IEEE members can read the entire article here. We'll take a look at some excerpts from it, and talk about what's changed over the last half century, and what hasn't.
As you read these excerpts, try to keep in mind that the article was published in 1969, and that the 1980s, a decade away, represented the distant future:
An examination of traffic conditions today—congested roadways, a large number of accidents and fatalities, extremely powerful automobiles—indicates the need for improvements in our highway system. Unfortunately, conditions will be much worse in the next decade, for it is predicted that the total number of vehicles registered in the United States in 1980 will be 62 percent greater in 1960, and 75 percent more vehicle miles will be traveled. If one should look further ahead to the turn of the century, he would see vast sprawling supercities, with populations characterized by adequate incomes, longer life-spans, and increased amounts of leisure time. One predictable result is greatly increased travel. The resulting traffic situation could be chaotic, unless some changes are instituted beforehand.
It is obvious that the traffic problems cannot be solved simply by building more and larger highways, for the for costs are too high, both in dollars and in the amount of land. Many alternative solutions have been suggested: high-speed surface rail transportation; a high-speed, electrically powered, air-cushioned surface transportation system… However, in the opinion of the writers, a majority of the of the public will not be satisfied with only city-to-city transit or even neighborhood-to-neighborhood transit via some form of public transportation. One needs only to witness the common use of private automobiles where such transit already exists. The role of a personal transportation unit is certainly justified by the mobility, privacy, and freedom afforded the occupants. It seems certain that this freedom, which dictates the spatial pattern of their lives, will not be relinquished.
I don't know about adequate incomes or increased amounts of leisure time leading to greatly increased travel, but what's definitely true is that more and more people are commuting longer and longer distances to get to work. The authors were certainly correct that the more time we spend in our vehicles, the more important autonomy becomes. At the same time, individual car ownership and usage is starting to get replaced by services that are more decentralized, but autonomy will enable that as well. It's funny to see that mention of a “high-speed, electrically powered, air-cushioned surface transportation system”; it sounds like they were foretelling the Hyperloop.
In this light, one satisfactory solution would be the automation of individual vehicles. This approach has been examined by a number of researchers, for in addition to the retention of the individual transportation unit, it appears that considerable improvement in highway capacity and safety as well as a considerable reduction in driver effort can be achieved. However, there is an extremely large number of possible systems for achieving this goal—the writers have counted 1296—and great care must be exercised so that an optimum or near optimum one is chosen.
The approach described in this article involves the concept of a dual-mode system, whereby the vehicle (which must be specially equipped) is manually controlled on nonautomated roads and automatically controlled on automated ones.
The system that the authors suggest, which is typical for automated driving system ideas of that era, relies heavily on infrastructure built into the highway directly. The well-defined and highly structured environments of highways are where today’s autonomous cars both perform the best and are the most valuable. The authors of the 1969 article weren't all that worried about automating other types of roads, because they figured that it simply wouldn't be worth the hassle and expense. In the near term, this is where many autonomy projects are finding success as well.
However, highway autonomy that's based on the highway itself is much harder to expand, and the total infrastructure overhaul needed to implement it in the first place wouldn't be cheap. Even in 1969 dollars, it sounds expensive:
It is expected that with the introduction and extended use of microcircuits, it will be possible to install all necessary equipment in the vehicle for several hundred dollars. The total investment in computers and highway-based sensors would probably average anywhere from $20,000 to $200,000 per lane mile (about $12,000 to $120,000 per lane kilometer), depending on the form of the chosen system and future technological advances.
One can expect two principal returns from such an investment: greatly increased lane capacity at high speeds and a reduction in the number of highway accidents. Estimates of the former range up to 800 percent and would depend, of course, on the chosen system design. The expectation of fewer accidents arises from the fact that an electronic system can provide a shorter reaction time and greater consistency than a driver can.
Sensing coils for an automated steering system, circa 1969 Photo: The Ohio State University
It's interesting that Fenton and Olson sound like they're more focused on increasing capacity than on safety, which is the opposite of how most vehicle autonomy projects are presented right now. This is likely because the efficiency benefits require some critical mass of autonomous vehicles all working together. It's much easier to achieve this with expensive automated highways and cheap automated vehicles, rather than 'dumb' highways that require each vehicle to have its own automation system, which is what we've got going now.
As for the vehicles themselves, the "near future" might provide something better than internal combustion, the authors hope:
It is probable that vehicles would be powered by the internal combustion engine; however, a number of other prime movers— the DC motor, the gas turbine, the steam engine, and the linear induction motor— may be available and practical in the near future. The eventual choice will probably be dictated by such factors as air pollution and the continuing availability of cheap fossil fuel.
One attractive possibility involves the use of electrically powered cars, which would be self-powered via batteries on non-automated roads and externally powered on automated ones. Here, power would be supplied through a pickup probe protruding from the vehicle, and control could be obtained by simply controlling the power flow.
An image from the original 1969 article, illustrating the idea of a vehicle drawing current for propulsive power from the roadway. Photo: The Ohio State University
Electrically powered vehicles that harvest electricity from highways and use batteries to get around elsewhere are currently being tested in Sweden.
Another important contemporary issue that the 1969 article mulls over: Should a human play any role at all in operating the autonomous vehicle?
An important question that is frequently raised is the advisability of allowing the driver to override the system. If he were able to do so, there would be a large measure of randomness in the system, which would be undesirable from a standpoint of both safety and system efficiency.
This remains one of the more difficult problems with consumer vehicle autonomy: unless you can promise 100-percent capability for your system, a human “driver” has to be involved. But how do you make sure that the human is alert and able to take over when necessary? Tesla reminds drivers to keep their hands on the wheel, and will begin to gradually slow the car if you persistently ignore it. Google, on the other hand, doesn't trust humans even that far, which is why it's working on autonomous cars without steering wheels.
The authors of the 1969 article have a slightly different perspective, but their concern about the “undesirable randomness” of human drivers foreshadows the day (it's getting closer, we promise) when the most dangerous car on the road will be the one driven manually by a human.
There is also a need for communication links to a central station so that there will be a complete "picture" of the traffic state at all times.
Combining vehicle autonomy with systems that allow vehicles to communicate with each other (and with a central coordination system) will allow for all kinds of exciting things, like flow optimization, cooperative route planning, and even intersections without traffic lights.
There seems little question that vehicle automation is technologically feasible; however, a tremendous amount of effort in both research and development will be required before a satisfactory automatic system is in operation. This effort must involve not only vehicle-control studies, but also an intensive investigation of the present driver-vehicle complex, since the knowledge gained will be necessary for the proper specification and introduction of the control system components. Further, the need exists for intensive overall system studies so that optimum strategies can be chosen for headway spacing control, merging and lane changing, and the interfacing of automated highways with other modes of future transportation.
The authors’ conclusion is as true now as it was in 1969. Since then, the focus has changed somewhat, with highway autonomy seen as just a step towards full autonomy—and not necessarily a step that can be taken independently. Technology has improved to the point where it's now feasible to pack all of the sensors and computers needed for autonomy into vehicles themselves, rather than having to rely on external infrastructure. This makes the transition to autonomous vehicles more straightforward, partly because it’s something that can be motivated by the market rather than by the government.
At the same time, though, I certainly appreciate the vision that the authors had for expensive automated highways that the average driver could take advantage of with a relatively inexpensive car. Here in Washington, D.C., for example, adding autonomy infrastructure to the beltway alone would vastly improve the commuting experience for an enormous number of people on a daily basis—that is, if existing cars could be cheaply retrofitted with the technology. This isn't the trajectory we're on anymore, but it's interesting to look back and think about what would have happened if we’d taken a different road.