Evaluation of the AHS article by Steven Shladover entitled "What if Cars Could Drive Themselves"?


J. Richard Guadagno, Cimarron Technology, Ltd.

I. Prospective "advantages" cited for automated highways.

1. While such a system might indeed eliminate some "traffic crashes that are caused by human errors such as misjudgments and inattention", it would at the same time introduce numerous new possibilities for crashes which would probably outweigh any gains. The replacement of a presumably attentive driver by a computer introduces to an automated highway precisely the same situation which we faced during the early days of development of InTranSys, when we were debating the relative benefits of surface and elevated rails. The computers must have the ability to see ice on the road ahead, or anticipate a patch of ice hidden around an oncoming bend. They must detect any kind of debris on the road, whether this is something which has fallen or been thrown from another vehicle, a rock or a landslide from the road embankment, flood deposits from a sudden storm, or any other happenstance. The computers must also be able to identify and predict the probable behavior of a deer, a cow, a dog – or even a child – which has chanced to enter the roadway. It must also determine if the road is covered by an inch or a foot of snow, or if it is raining so hard that the car will tend to hydroplane. It must also be able to detect wayward vehicles which have improperly entered the wrong lane. It must be able to do all this in a dense fog which the sleeping driver is unaware of. And it must also do all of this with far better precision, speed, and perceptiveness than a typical driver is capable of.

And what happens if a car – the one in question or another ahead of it – runs out of gas? Or if it gets a flat tire? Or if any of the hundreds of other things which can go wrong with a device as complex as an internal-combustion-engine powered automobile should fail while under way? And wouldn’t the teenage nuts who enjoy dropping concrete blocks on cars from overpasses be far more tempted to do it if they knew they wouldn’t be seen and couldn’t be identified? All of these possibilities can – and will – introduce critical safety hazards of other types. Are today’s computers capable of anticipating and correcting for all such incidents? If so, how? If such events happen with anywhere near the same frequency as they do today, the safety of the system will be compromised far beyond current problems.

You mentioned that these automated cars would travel in a "protected lane". If safety is not to be compromised, such a lane would duplicate what I foresaw back in the 70’s when we briefly considered surface rails for InTranSys, and which is described in detail on the first page of the Track System section of the Technical Report available at the InTranSys’ website: a completely enclosed tube which would represent a barrier to other traffic comparable to that of the Chinese Wall. When one also considers the need for innumerable over- and underpasses for existing local traffic, such a "lane" would also cost several times as much to build as an elevated system, which would be free from all of these problems. It was this comparison, of course, which induced us to settle on elevated rails as the only sensible alternative.

2. Advanced driving skills will still be needed by every driver for local travel, regardless of the system employed.

3. The statement that not just the wealthiest might enjoy automated cars is contradicted later in the paper, under NONTECHNICAL CHALLENGES, paragraph 2. How long will it take before these SST-like special favors for the wealthy will be conferred upon the rest of us?

4. The concentration of polluting emissions for each traveler would actually be greatly increased by spacing internal-combustion-engine-powered vehicles "close enough to each other to benefit from aerodynamic drafting", and not reduced as stated. The exhausting of the waste products of one car directly into the air intake of the following one would introduce an intolerable health risk. Only pollution-free electrically powered vehicles can offer such advantages, and they can do so infinitely better.

5. So "the capacity of a freeway lane might be doubled or tripled." For comparison, InTranSys will effortlessly increase it 18-fold.

6. General: The word "might" is used throughout these claims, indicating a great degree of uncertainty on the part of the author. InTranSys, on the other hand, can absolutely guarantee that much greater benefits WILL definitely be gained in every possible category.

II. Operation

1. The on- and off-loading procedures are identical to those developed for InTranSys decades ago. Could this be where the idea came from?

2. Contrary to what Shladover claims, the many different technical developments all require exotic technologies, especially when compared with the extreme simplicity of InTranSys. For example, the computers installed within each vehicle are almost infinitely more complex, and require far more bits of information for adequate operation, than even the area-wide traffic control computers for InTranSys, which are designed to control the precise location (to a much higher degree) of millions of vehicles at once. The roadside computers, together the interconnections allowing communication between them and all the vehicles using a given section of freeway, will also add additional orders of magnitude to the overall complexity of the system.

3. The magnets buried beneath the roadway with initial accuracies of no better than a centimeter are far more subject to displacement by factors such as frost heave, unstable road base, or geological shifting than are the traffic-controlling linear synchronous motor elements used by InTranSys. This fact was another reason we opted for overhead suspension from pre-cast, post-tensioned concrete segments, which also have added provisions for adjustment even in the event of such long-term effects as geological instability. How long could an automated roadway be expected to last? Certainly not for the 50 years or more expected for InTranSys. It should also be pointed out that the binary code provided by alternate plus and minus magnets has long been an automatic, and far more precise and reliable, feature of InTranSys.

4. The required stops for getting a ticket at the beginning of a journey and for paying the bill at its end introduce delays unnecessary for InTranSys, which provides for the identification and location of each vehicle at every instant – knowledge which is provided to the system computer. Moreover, there is no need for any vehicle or driver to be checked for travel suitability at the beginning and end of each InTranSys trip, since such knowledge is immaterial to the operation of this much simpler system.

5. Contrary to the situation for proposed automated highways, the state of the art for the far simpler software needed for InTranSys is not at all in question. It was when the idea was first conceived in 1971, but computers have long since advanced far beyond the complexity needed.

III. General considerations.

Let us compare the probable accomplishments of automated highways – if all the remaining bugs were to be successfully eliminated – with those of InTranSys, according to the twelve standard criteria which have been used for many years:

1. Long-term sustainability. Ever since the first energy crisis of 1973 pointed out the impending exhaustion of world petroleum resources, this issue has been the most important consideration for any future transportation system. As a result, it has long been the compelling argument for InTranSys. But it is not even addressed by automated roadway systems, which therefore offer absolutely nothing at all toward the achievement of this essential goal.

2. Environmental acceptance. The original impetus for the development of InTranSys was the elimination of transportation-generated air pollution. While this issue has since been forced to take a back seat to sustainability, it is still important. InTranSys’ independence from the internal combustion engine and the total substitution of electric power produced primarily from solar collectors has the potential for reducing this problem to insignificance. The continuing dependence of automated roadways on oil-derived power would also accomplish nothing in this respect. In fact, the proposal to cram the cars up against each other to reduce drag would increase passenger-inhaled pollution to new and intolerable heights.

So would the use of an enclosed roadway, which would be necessary for adequate safety. A paradox inherent in such a tube-like structure is that the use of internal combustion engines within such an enclosure would require massive ventilation facilities even at present traffic densities. If these consisted of vehicle-generated air movement, it would greatly increase drag, and consequently energy requirements as well (see next section). If, on the other hand, a parallel, separate ventilation system were to be used, both the size of the structure and the added energy requirements would have to be much greater. Remember that the ventilation tunnel for the Eisenhower highway tunnel on I-70 in Colorado had to be built to a much larger size than either of the traffic tunnels. Incidentally, vehicles using internal combustion engines will be allowed on InTranSys, but their engines will automatically be turned off during transit for these safety reasons.

Land use is another important environmental factor. Overhead rail systems such as those proposed for InTranSys would interfere very little with existing transportation and other land uses. But the construction of yet another independent network of surface corridors, and especially one which would require an essentially closed pathway, would do enormous harm.

3. Energy efficiency. The 10- to 12-fold increase in energy efficiency of InTranSys’ linear synchronous motors over today’s engines would allow both a deep cut in transportation energy use and a potentially much wider variation in energy sources. Automated roadways, once again, would do nothing to improve this situation, and would probably even cause it to worsen.

4. Alleviation of traffic congestion. Of all these twelve criteria, this one appears to be the sole purpose of automated roadways, and the proclaimed benefits even in this field would be quite trivial when compared with those of InTranSys.

5. Compatibility with other traffic modes. InTranSys can very easily be adapted to form seamless extended multi-mode travel networks with other electrically powered systems such as personal rapid transit and magnetic levitation. Automated roadways offer nothing along these lines.

6. Weather invulnerability. This is an automatic feature of InTranSys, due to its overhead suspension and the consequent covering of all moving parts. Automated roadways offer no improvement over our present system, and could in fact end up being far inferior unless a completely enclosed roadway is used.

7. Extent of service. This is the greatest virtue of our present automobile-dominated system. It would not be improved by the use of automated roadways. On the other hand, the added public transportation facilities offered by InTranSys could greatly extend the total availability of service, with regard to both geographical extent and population served.

8. Speed of travel. The only improvement offered by automated roadways would be a marginal increase in travel speeds during rush hour traffic. InTranSys, on the other hand, would offer guaranteed speeds for both urban and rural traffic which would be triple those now possible on our present system under optimum traffic conditions.

9. Safety. This is a sticking point. It is not know with any certainty whether automated roadways would be safer or less safe overall than our present driver-controlled system. On the other hand, InTranSys can guarantee not only a 99% + improvement for all traffic which it carries, but also at least an 85% improvement for our overall ground transportation system as a whole.

10. Traffic capacity. As mentioned earlier, InTranSys can offer an 18-fold increase in total traffic capacity per lane for both urban and rural travel. The modest 2- to 3-fold increase of automated roadways, available only under conditions of extreme congestion, is trivial by comparison.

11. Cost: Total construction costs of InTranSys (by far its greatest expenditure) may be as high as half those of an enclosed automated roadway. But maintenance and operational costs will be only a tiny fraction as high. And energy costs, which will undoubtedly be by far the biggest future factor for any non-electrical system, will be comparatively negligible for InTranSys. Since we don’t even know if any synthetic fuel will ever be able to replace today’s gasoline, we cannot offer an accurate estimate of what its costs might be. But total travel costs on automated roadways are sure to be several times as high as those for InTranSys.

12. Energy independence. This issue, once touted by President Nixon as the greatest goal of his administration, has been forgotten since then simply because we haven’t yet run out of oil. InTranSys can guarantee it, while the adoption of automated roadways can only make us even more dependent on foreign suppliers – at least for the short period that those will last. We must also include in this category the enormous expenditures required for a large and perpetually ready military force, whose primary purpose today, even though we are not willing to admit it, is the protection of our foreign petroleum supplies.

It is obvious that, when one compares the potential accomplishments of alternative transportation systems with the list of goals outlined above, automated roadways have virtually nothing to offer. Only automated, electrically-powered, elevated railway systems such as InTranSys can satisfy either our future desires or our future needs. Then why are we bothering to devote even one whit of our valuable time and effort to the development of so-called smart cars? In my opinion, these devices, no matter how "smart" we might succeed in making them, are nothing but toys – perhaps fun to play with, but offering no tangible benefits. They merely represent the application of highly sophisticated and overly complex technologies to the preservation of an archaic institution – the internal combustion engine – which is not only hopelessly flawed but also totally anachronistic.

In short, the smart car is a dumb idea. What we really need instead is a smart transportation system.


Last modified: June 13, 2000