hodor@hplabsb.UUCP (06/27/84)
The federal government is implementing a massive road reconstruction plan.
Some of this will no doubt be allocated to improving the roads in major
cities to try to alleviate some of the traffic congestion. This will cost
the people of the United States in taxes. I would like to propose only
implementing the repair of the existing roads and approaching the problem
of congestion from a different direction.
The first part of the proposal is the 55 mph speed limit should be eliminated.
This has outlived its time. The control of the maximum speed limit should
be set by the states.
Below is a table of what happens to the amount of traffic that an already
existing road can handle at various speed limits. This is assuming that
a safe distance of 1 car length for every 10 miles per hour of separation
between cars. I took a car length to be 20 feet.
Speed Throughput Density
mph Cars/hour cars/mile
----------------------------------
1 258 240
10 1320 132
55 2234 41
70 2310 33
100 2400 24
Some observations from the above table show that at 1 mph the road becomes
a parking lot with a density of 240 cars per mile. If we could regulate
the traffic getting onto the freeway the throughput of the freeway would
increase. By the above chart the throughput would increase by a factor of
nine going to 55 mph. Going from 55 mph to 70 mph only increases the
throughput by about 3%. This is due to the reduction in the density of
cars that the road could safely take (again the 1 car spacing for each
10 mph).
The second part of this proposal involves the use of electronic position
detectors for future cars. This device would allow all cars to be about
1 car length apart no matter what the speed. The electronic control
would not allow a person to get any closer than a specified distance.
The electronic control would control the breaks and put a maximum limit
on the speed based on the traffic flow. Electronics are well noted for
their ability to react much faster than a human.
Below is a table of the speed and throughput of cars using the same road as
stated above. Only this time the cars are equipped with this electronic
position detector.
Speed Throughput
mph cars/hour
--------------------
1 132
10 1320
55 7230
70 9240
100 13200
The density of cars could remain a constant of 132 cars per mile. Note that
as the speed of the cars increase the throughput of the cars also increase
linearly. Also one of the big advantages of this type of device would be the
dramatic increase in throughput of the existing freeways. At 55 mph the
throughput increases by more than 3 times. If the speed of the cars could
be increased to 70 mph the throughput would be increased by more than 4 times.
With electronic position detectors in cars the current highway system would
be able to support more than 3 times the amount of traffic that we have on
our freeways today. I believe this could be done for much less than anything
that would try to improve our highway system through more construction.
A couple things I like about this idea are:
-Not all cars have to have the detector to gain the benefits of
the new system.
-With the use of high reliability design the additional safety
provided by the detector would save lives.
-People would spend less time commuting or transporting goods due
to the higher speeds that would be possible. This will provide
more discretionary time for people and reduce the cost of goods.
Conclusion
I hope more people write to their state and federal government representatives
about eliminating the 55 mph speed limit. Detroit, I hope you pick up on
the position detector idea and run with it. wmartin@brl-tgr.ARPA (Will Martin ) (06/28/84)
Despite the "high reliability electronics", just what happens when the car ahead has a sudden engine failure when the road is filled with cars one car-length apart, moving at 100 mph?
an@hou2h.UUCP (A.NGUYEN) (06/29/84)
> From: hodor@hplabsb.UUCP (Ken Hodor) > The second part of [my] proposal involves the use of electronic > position detectors [which] would allow all cars to be about 1 car > length apart no matter what the speed ... The electronic control > would .. put a maximum limit on the speed based on the traffic flow. Nice try Hodor, but I have to oppose that just on principles! The logical extension of your idea would be electro-mechanically guided vehicles, probably running on some kind of track. You get in, punch in where you wanna go, and sit back and listen to the "Clockwork Orange" soundtrack. We already have that -- it's called a TRAIN. What's next? Electronic regulators on your toilet tissue dispenser so you can't use anymore than 4 squares at a time?! Oh you have diarrhea? Tough sh*t! > With electronic position detectors in cars the current highway system > would be able to support more than 3 times the [present] amount of > traffic ... I believe this could be done for much less than anything > that would try to improve our highway system through more construction. I don't think you have a firm grasp of the problem. Congestion occurs because of the sheer volume of traffic *AND* the diverse speed, skill, and tact of all those drivers. On some roads, you can raise the speed limit to 100 mph and gain nothing but instant carnage. Take any highway thru NYC, LI, or Hartford, CT. Right exit, left exit, center exit. Exits every three feet! The answer there *IS* most definitely *MORE* roads. (And better roads, too. Damn these signs that are located 2 feet from the exit. And yes, damn those left exits!) Furthermore, even if you raise the speed limit, there will still be people who drive way below the limit. People who are not sure where they are going. Out of towners. Heavy trucks. The only way for all these people to fit on the same road and not kill the flow is to have everyone strictly disciplined on the rules of the road. Keep right pass left. Check blind spots. Signal. CONCLUSION: MORE ROADS, AND BETTER DRIVERS! Au
rs55611@ihuxk.UUCP (Robert E. Schleicher) (07/03/84)
The idea of using electronic position sensors to minimize car-to-car distances (and thus get more cars on a crowded highway) would be fine if the only variable in stopping time and distance was reaction time of the driver. The electronics would effectively eliminate the reaction time to some very low number. However, actual stopping distances of different vehicles vary tremendously (fully-loaded semi vrs. a 2500 lb. sports car with four-wheel disks nd fat tires, for example), so the electronics would also have to somehow know how fast the car in front was capable of stopping, if the car in front could stop quicker than you. Another approach would be to have all vehicles programmed to have a maximum braking power (or minimum stopping distance equal to the worst vehicle on the road. This makes no sense whatsoever. While electronics will undoubtedly make braking systems safer in the near future, I think it will only be in the mode of a fail-safe device that will prevent drivers who aren't paying attention from rear-ending the car in front. The other use of electronics in braking systems that has already been developed (by Mercedes and others) is in anti-lock systems which automatically prevent wheel lock-up during panic braking, regardless of road and weather conditions. These use rotation sensors on each wheel, and limit additional brake fluid to any wheel that is rotating appreciably slower than the other wheels. This system was available on some higher priced Mercedes as an option, and works very well. You can slam on the brakes in a turn on a snowy road, and the car will slow down as fast as possible without sliding. Bob Schleicher ihuxk!rs55611 AT&T Bell Laboratories
hodor@hplabsb.UUCP (07/05/84)
A question was raised as to what happens when a car has a sudden failure when cars are using a position detector. Since each car has a position detector any failure by a single car will be detected in cars immediately following it. All cars immediately following the first failing car would slow down. This slowing down would be done automatically by the position detector. Ken Hodor hplabs!hodor
ark@rabbit.UUCP (Andrew Koenig) (07/10/84)
I once saw a suggestion that traffic congestion could be ameliorated in New York City and similarly crowded urban areas by allowing left turns on red. It wouldn't make the traffic any better, but it would be a whole hell of a lot less boring!
ams@hou4b.UUCP (Andrew Shaw) (07/11/84)
<> Actually the free left on red idea has been implemented in many states. In urban areas, such as New York, this idea would not make traffic congestion more interesting, since it applies, obviously, only to left turns onto one- way streets, and is thereby the functional equivalent of the current right- turn on red we see nowadays. This idea is more practical in areas where the ratio of one-way to two-way streets is high, ie in congested urban areas. Andrew
hodor@hplabsb.UUCP (07/13/84)
>From: an@hou2h.UUCP (A.NGUYEN) >Subject: Re: Eliminate traffic congestion >> From: hodor@hplabsb.UUCP (Ken Hodor) >> The second part of [my] proposal involves the use of electronic >> position detectors [which] would allow all cars to be about 1 car >> length apart no matter what the speed ... The electronic control >> would .. put a maximum limit on the speed based on the traffic flow. >Nice try Hodor, but I have to oppose that just on principles! The >logical extension of your idea would be electro-mechanically guided >vehicles, probably running on some kind of track. You get in, punch >in where you wanna go, and sit back and listen to the "Clockwork >Orange" soundtrack. We already have that -- it's called a TRAIN. I am sorry but I do not understand your "principles." Comparing a TRAIN with its limited area of coverage to the versatility of a car that can go almost anywhere does not make sense. I personally like your logical extension of the idea to guided vehicles. I can think of much better things to do with my time than to have to think about how do I go from here to there. >> With electronic position detectors in cars the current highway system >> would be able to support more than 3 times the [present] amount of >> traffic ... I believe this could be done for much less than anything >> that would try to improve our highway system through more construction. >I don't think you have a firm grasp of the problem. Congestion >occurs because of the sheer volume of traffic *AND* the diverse >speed, skill, and tact of all those drivers. When talking about the diverse speed, skill and tact of all drivers one must also consider the standard deviation. From what I have seen on the freeways I would say there is rarely a person that drives less than 50 miles per hour on a 55 mile per hour freeway. >Furthermore, even if you raise the speed limit, there will still be >people who drive way below the limit. People who are not sure where >they are going. Out of towners. Heavy trucks. The only way for all >these people to fit on the same road and not kill the flow is to have >everyone strictly disciplined on the rules of the road. Keep right >pass left. Check blind spots. Signal. I have a hard time believing this is the "only way." I think technology can also be further exploited to improve all ways of life. >CONCLUSION: MORE ROADS, AND BETTER DRIVERS! I would be interested in finding out how we could produce better drivers. If anyone has any ideas as to how this could be done please offer it to the world. The proposal that I made takes into account the varing abilities of the drivers of today and tries to substitute technology where there is a definite lacking in the human being. Ken