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Publication numberUS3188927 A
Publication typeGrant
Publication dateJun 15, 1965
Filing dateAug 28, 1958
Priority dateAug 28, 1958
Publication numberUS 3188927 A, US 3188927A, US-A-3188927, US3188927 A, US3188927A
InventorsWoods Allan M
Original AssigneeWoods Allan M
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Traffic control means
US 3188927 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

June 15, 1965 A. M. wooDs 3,188,927

TRAFFIC CONTROL MEANS Filed Aug. 28, 1958 3 Sheets-Sheet 1 Fl G. I I INVENTOR. ALLAN M. wooos BY fWV/U- June 15, 1965 A. M. WOODS 3,188,927

TRAFFIC CONTROL MEANS Filed Aug. 28, 1958 3 Sheets-Sheet 2 I "15. 1L 0 q a I D 9 I O a l r C) Q l o l I u 0 C;

A. v s N I .m N INVENTOR. Y M wooos \JN ALLAN BY MW ww June 15, 1965 A. M. WOODS 3,188,927

TRAFFIC CONTROL wms Filed Aug. 28, 1958 3 Sheets-Sheets ALLAN M. WOODS United States Patent Ofilice 3,188,927 TRAFFIC CONTROL MEANS Allan M. Woods, 7 Hamilton Place, Garden City, N.Y. Filed Aug. 28, 1958, Ser. No. 757,827 1 Claim. (Cl. 94-15) This invention relates to traffic control means and more particularly to highway marking means for the control and spacing of automobiles on the highway.

The present system is primarily for use on main trafiic arteries, parkways and thruway-type high speed highways having few or no traffic lights.

The present system is intended to reduce or eliminate many of the hazards and difiiculties of travel and to improve trafiic control and movement on highways.

Such hazards include accidents involving several cars in bad pileups, tratfic jams with cars backed up before some minor road obstacle, difiiculties in merging lanes of trafiic, difficulty entering onto express highways from approach ramps, and constant driver tension in massed traflic moving erratically at high speed.

These hazards of travel on such highways result principally from:

(a) Insuflicient distance between moving vehicles.

(b) Erratic speed control of some drivers.

(c) Excessive high speeds of some vehicles.

(d) Comparatively slow speed of other vehicles.

(e) Tr-afiic pileups resulting from road obstacles such as construction, blowouts, repairs, accidents, etc.

( f) Merging of two or more lanes of traflic.

(g) Entrance of vehicles onto the highway.

Under previous systems, the drivers of vehicles were permitted freedom to operate their automobiles in any fashion they desired, provided they did not exceed the speed limit of drive in such a radical manner as to be termed reckless.

The result of this previous method was that most drivers, having no way of knowing and no discipline to teach them, usually drove with their automibles too close to preceding cars. And when, for any reason it became necessary for them to suddenly stop, or to slow down, or to take evasive action, they were unable to do so in the space available ahead of their car.

Furthermore, with no way of knowing and no discipline to teach them, when the car ahead of them slowed down at .a merger point or at a road obstacle, they would drive so close to the vehicle preceding them that two or more lanes of traflic could not merge together to pass around the obstacle except very slowly.

It is claimed that the present invention makes possible the reduction or elimination of these hazards by controlling the spacing between vehicles and has the following purposes and objectives:

(a) Safe and sufiicient spacing will be maintained between vehicles on the highway to permit avoidance of accidents regardless of speed.

(b) Vehicles will proceed at a steadier speed in the line of moving tratfic.

(c) There will be less variation in speed as between different vehicles; slow drivers will be encouraged to drive faster and fast drivers will be persuaded to drive slower.

(d) Trafiic will proceed smoothly around road obstacle-s.

(e) The merging of multiple lanes of trafiic will be accomplished without pileup of vehicles before the point of merger.

(f) Vehicles will be enabled to enter upon a high speed highway without danger to themselves or to the drivers of cars proceeding at high speed on the highway.

(g) The passage of fast vehicles around trucks and 3,188,927 Patented June 15, 1965 other slow vehicles on the highway will be readily accomplished without hazard.

(h) The movement of police cars, ambulances and other emergency vehicles through lanes of moving traffic on high speed highways will be facilitated.

A recommended spacing between moving vehicles on a highway is one car length for each 10 miles per hour of vehicle speed. The system of the present invention pro vides a guide for the control of spacing between cars, comprising of dots or markers on the surface of highways at spaced intervals down the center of each traflic lane, together with such roadside signs as will instruct drivers as to how to maintain adequate spacing between vehicles consistent with the speed of traflic on that highway or that particular stretch of highway.

For example, on a stretch of highway over which it is desired to maintain a spacing of feet between moving vehicles, dot-s or markers will be applied to the surface of the highway at 34 /2 foot intervals down the middle of each traflic lane according to a formula which will be discussed.

At frequent intervals along this stretch of highway, signs will be erected which will instruct drivers to constantly keep two of the dots or markers in view between their car and the car preceding them. These signs will be designed to impress on the drivers the necessity for always keeping at least two of the dots in view on the highway ahead of them by not driving too close to the car preceding.

In order for them to constantly be able to see at least two dots on the highway ahead, it will be necessary for them to remain at least approximately 90 feet behind the preceding vehicle.

Preferably the distance between dots on the surface of the roadway will vary to suit the particular road or trafiic conditions. At merger points or entrance points on high speed highways, it will be desired to increase the distance between dots and thereby provide greater space between moving vehicles to permit the merger or entrance o-f other vehicles into the moving lane of trafiic.

At other points on highways, for example where trafiic generally moves slowly, less distance between dots will be desirable since cars can safely proceed closer together.

Preferably it will be arranged to have the dots painted a different color on the highway to notify drivers of hazards ahead or of changes in spacing desired. For example, a change of color from white dots to bright yellow dots may be used to indicate that close attention by the driver is needed while traversing the road immediately ahead.

It is anticipated that constant, repetitive exposure to this present system of trafiic control and discipline will influence drivers to subconsciously maintain a constant speed, not too slow, not too fast, in keeping with the pace of general trafiic flow.

The speed or pace may be pre-established, and reestablished at intervals, by police cars, by moving indicators at intervals along the highway, by lines of lights set in the road or by the roadside, arranged to flash at predetermined time intervals to create the illusion of lights moving at a precalculated speed, or by such other means as will become apparent to those skilled in the art to which this invention pertains.

The present system is particularly useful at merging points. If the spacing is maintained and the cars do not close up, the two lanes can merge at a good rate of speed with considerably more safety than the usual starting and stopping bumper to bumper.

Maximum speed laws are not the complete answer to trafiic control. Smooth flow and adequate spacing patterns will tend to eliminate multiple car accidents. It is safer at 60 m.p.h. in a smooth pattern than at 20 or'30 m.p.h. in an erratic pattern.

Most drivers will stay in a reasonably paced pattern. It is only discontinuities in the flowsuch as very slow or. very fast drivers, changes in the road conditionssuch as curves, hills, or entering traffic that break up the smooth flow. It is analogous to laminar flow and turbulence in air flow or liquid flow.

The change in dot spacing of the present system is analogous to velocity modulation in electron flowv when the electronsare bunched, except that. the idea here is to prevent bun'ching caused by. speed variation.

Most drivers will respond to cially if this is the course of leasttrouble for them. It discipline is well organizedand people arefwcll educatedas to what is expected of them, as in military discipline,

1 4 r The nearest driver has two markers M1, M2, view; the next driver sees markers M3, M4, etc. The markers are placed along the center of the lane with a predeter mined spacing. The markers may be painted white dots preferably painted with' a paint" having high reflection characteristics for night driving or other equivalents. The spacing ischosen by first determining the predetermined speed, for instance, at. a speed of 60 mph it would be desirable to space the cars six car lengths or about 90 feet. Thenthrough application of the following formula, the

' correct spacing between markers or dots to achieve the reasonable control espe-' they willrespond practically one hundred percent and 1 hopeless cases will be immediately apparent;

Traflic control is a-matter of educatiom propercommunication, applied'psychology, plus the new techniques of subconscious motivation developed by the advertising industry. The present invention'ma'kes. use of these techniques. It is believed that the spaced. markersplus repeated visual instructions will aves subconsciousaswell as a conscious etfectand may even develop into a conditioned reflex. 1

Accordingly, a principalobjectof the. invention is to provide new and improved traffic. control 'means.

1 Another objectof'theinvention is to provide means to maintain a. smoothqtraffic flow pattern.

Another object of theinvention is to. proyide means to,

maintaina predetermined safe spacing between cars.

Another object of .the invention is toprovide. means to desired space between cars will be attained:

cars desired Dot Spacing=Distance between 34.5 feet where K:the nearest pointon the road a driver may see in front. An average value for K would be 21. feet. a If the dots were spaced 34 /2 feet apart and the drivers instructed to keep two (2) dotsin view at all times, a safe spacing Condition would be; maintained at all times. Suitable signs are preferably'installed at periodic intervals along thehighway as follows:

maintain'a predeterminedsafe spacing between cars com- 1 prising a series of markers. having predetermined spacing combined with visual instructions to maintain a spacing of. two or more markers.

Another object of the invention is to providean im-' proved means of merging moving lanesof traflic.

Another object of the invention is to provide a means of notifying motorists of hazardous traffic zones.

Another object of the invention is to: provide an improved means of expediting the entrance.of vehicles onto express highways.

Another object of the invention is to. provide a method of regulating the spacing between moving vehicles on the highway consistent with the speed of those vehicles.

Another object of the invention is to provide a means of spacing moving vehicles on highwaysso that the likelihood of accidents will be reduced. y

Another object of the inventionis to provide a means of spacingvehicles. on highways with the result that police vehicles, ambulances and other emergency equipment will be enabled toprogress through the. openspaces between vehicles regardless of thevolume of traffic.

Another object of thelinvention is to provide a means: of spacing vehicles in lanes of trafficwith the result that.

the lanes will be readily able to converge into singlelanes todetour around roadobstaclessuch as accidents, ro ad repairs, stalled cars,.etc.

. Another object of the invention is tov stabilize the conduct of operators of vehicles on the highway consciously and subconsciously with. the result that. thisimproved conduct and discipline will. reducethe strain and-.hazards.

of motor vehicle operation.

' These and other objects of apparent from the following specification and. drawings, of which? V FIGURES 1 and 2 are diagrams illustrative. of the invention, and i FIGURE 3 is a schematic showing atraveling signal paced for use with the systembf the present invention.

the invention, will become KEEP 2 DOTS IN 'VIEW IN FRONT OF YOU Where local conditions. change such as on bills or around curves or in merging-traffic conditions, the spacing of the dots may be gradually varied to increase the spacing between cars at these points. 'This variation will not cause a bunching or closing up if it is done gradually since it is only more or less abrupt discontinuities that will break up the pattern. A three or more dot system could. be used, but it is felt that two is the most convenient number. I

FIGURE -2. illustrates a merging situation where the distance between dots is gradually increased from a 1 unit spacing in the area A to a}1% spacing in the area B, to a 1 /2, unit spacing in the area CQand to a 2 unit spacing in the, area Da The areas A, B, C, and. D should be reasonably long,,for--instance, each A ,mile. Also, the

TRAFFIC ZIPPER KEEP 2 DOTS IN VIEW DO NOT CLOSE UP they will be able to merge. at a good rate of speed in a relatively smooth manner and with considerably more safety than caused'by cars tryingto break into. a tightly closedline of traffic. Thesame method may be used where new trafiic enters the main road at entrances to the highway.- It is assumed that these entrances will be of the gradual taperingvariety common to the modern express highway.

The marker dots themselves will not establish vehicle speed. However, if the drivers are'instructed to maintain a certain speed which-amajority of them will probably follow, they will set a pattern which 'will more or less coerce others to conform;

However, if desired,,separate speed pacing means may beprovided. This may be done with anocc'asional police car or spaced markers 10, 11, and 12 FIGURE 3 mounted on a travelingbelt B which is supported by and driven FIGURES 4A-4G are diagrams illustrative of theinf vention. V

' FIGURE'l shows a view illustrating proper spacing.

by the pulleys 13, 14, 15 and so forth. Markers on the lower portion of the belt returning in the opposite direction are preferably Shieldedby a shield 20. This belt need not be continuous along the road but may be spaced at periodic intervals.

, Alternatively, the traveling spaced markers may be provided'by flashing spaced-lamps along the side of the A road in a predetermined pattern to simulate a group of spaced markers moving at the desired speed. The lights would be more effective at night, and could be made quite dim to minimize any detracting effect.

This invention also offers a means to eliminate a phenomenon of express highway traflic patterns, called the accordion effect.

This is the peculiar condition commonly found on fast highways where traffic will be badly bunched although moving very fast, and yet there will be miles of open road before and behind the bunch. Apparently trafiic will bunch up like that and then suddenly open up again and spread out, only to close up again.

It is believed that this accordion effect is the result of cars piling up too close to one another when some minor cause results in a few of the leading cars slowing down momentarily. Because cars bunch up too close to one another, they are unable to accelerate again quickly. Each car must wait for the one ahead of him to get out of his way before he can accelerate. Thus all cars behind are delayed from accelerating until each of the individual cars ahead has gained the necessary space in front of him.

If the system of the present invention was used and drivers trained not to close up, there would be room in front of each car to accelerate and the whole group could do it as quickly as their reflex action permits. Under such a condition, there would just be a slight slowdown of the whole group and then a quick resumption of former speed.

Instructions such as:

MAINTAIN 2. DOT SPACING are ambiguous, as follows:

FIGURES 4A and 4B, show the result when the dot system is misinterpreted by the motorist X if he attempts to relate the exact distance between 2 dots as the distance he should maintain between his car and the one Y ahead.

In FIGURE 4A he actually has 2 dots on the roadway between his car and the one ahead. He cant see dot number 1, but he has judged it to be there.

In FIGURE 4B, as he proceeds forward, there is an interval When he actually has only one dot on the pavement between his car and the one ahead, but if he assumes that to have the 2 dots there momentarily at regular intervals he is abiding by a 2 dot regulation, the result is that he will run only 40 feet behind the preceding car. As a result he only has 40 foot spacing.

This, of course, is an extreme example but it would be the result of the thinking of some individuals unless they were taught to drive their cars with at least two dots in view on the pavement in front of them at all times.

FIGURES 4C and 4D, show what would be a more common misinterpretation of the two dot rule.

In FIGURE 4C the motorist in car X is interpreting the 2 dot rule to mean that he should keep the space equivalent of two dots between his car and the one ahead and he is making an effort to hold that space even though he cant see the entire space between dots 1 and 2.

In FIGURE 4D you see the result as car X proceeds forward. Now he can see two dots momentarily and has calculated he still has the space equivalent of two dots between him and the car ahead. As a result car X only has 70 foot spacing.

This would be the most common interpretation of the two dot system if motorists were not properly indoctrinated in the proper method of staying back far enough to see two dots coming at him on the pavement all the time in kinematic fashion.

A proper instruction is:

KEEP TWO DOTS IN VIEW For instance, FIGURES 4E, 4F, and 4G, show the correct use of the 2 dot system.

In FIGURE 4E car X is staying back far enough so that he can actually see dots 1 and 2 between his car and car Y. Dot number 3 is coming at him from under the rear of car Y and as soon as dot number 1 has vanished from view under his car, he will pick up dot 3 in his line of vision.

FIGURE 4F shows that happening. He now has dots 2 and 3 in his line of vision. Dot number 1 has disappeared under his car.

FIGURE 46 shows him proceeding further. Dot numher 2 has disappeared from view and he has picked up dot 4. Note that dot 2 has not actually passed under his car, but it is no longer in view. The distance K will vary slightly for different cars but is not critical. A value of 21 feet for K has been found to be an average value.

This is a most important feature of the system. If drivers can disregard all of the business of trying to estimate space and make no effort to use the dots or spaces between the dots as a guide to distance and instead, merely view the road as it unreels before them, keeping 2 dots in view at all times, they will automatically and subconsciously without effort or calculation be the correct distance from the preceding car. This is by far the simplest and most effortless means, if drivers are properly educated.

It is by keeping two or more of the dots constantly in view on the road ahead, that the driver automatically and without mental calculation maintains a prescribed distance from the car ahead.

In other words, it is primarily the kinematic effect of the multiple dots on the highway appearing to move constantly toward the driver, which accomplishes the objective.

Under prior systems the most that has ever been done has been to mark off on the highway the distance desired between cars. This necessitated the difficult task of relating the distance between your car and the car ahead. Under my invention no such optical gymnastics are necessary. Just so long as one is able to glimpse at least two dots on the road ahead at all times, the task is automatically accomplished.

I claim:

Traflic control means comprising a roadway, a line of markers on the road surface substantially in the center of a traffic lane and equally spaced a distance according to the formula, desired car spacing=2S+K, where S=spacing between markers and K=a constant of substantially 21 feet, where desired car spacing is related to the maximum legal speed, whereby drivers keeping two markers in view at all times will maintain the desired car spacing.

Proceedings, Highway Research Board, Washington, D.C., January 15-18, 1952, pages 359, 360, 369.

JACOB L. NACKENOFF, Primary Examiner. WILLIAM I. MUSHAKE, Examiner.

Patent Citations
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US2318722 *Jan 18, 1939May 11, 1943Guidalite CorpHighway-illuminating system
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3593262 *Dec 13, 1968Jul 13, 1971Emi LtdA traffic control system for merge junctions
US5134393 *Apr 2, 1990Jul 28, 1992Henson H KeithTraffic control system
US5278554 *Apr 20, 1992Jan 11, 1994Marton Louis LRoad traffic control system with alternating nonstop traffic flow
US6989766 *Dec 23, 2003Jan 24, 2006International Business Machines CorporationSmart traffic signal system
US7021857 *Sep 6, 2002Apr 4, 2006Koninklijke Philips Electronics N.V.Dynamic road marking system and road segment provided with said system
US7147400 *Jan 17, 2003Dec 12, 2006Koninklijke Philips Electronics N.V.Road marking system
US7151992 *Mar 17, 2004Dec 19, 2006Vrbia, Inc.Externally activated non-negative acceleration system
US7607857 *Apr 27, 2007Oct 27, 2009Swonger Jr Karl WilliamAssured safe following distance highway markings
US8142100Jul 14, 2010Mar 27, 2012Harold Ralph HansonAnimal crossing warning zone and method of applying it to a roadway
US8517627Jun 13, 2012Aug 27, 2013Rhino Advertising Pty LimitedMethod of placing visible advertising
US20040047685 *Sep 6, 2002Mar 11, 2004Van Der Poel Lucas Leo DesireeDynamic road marking system and road segment provided with said system
US20050134478 *Dec 23, 2003Jun 23, 2005International Business Machines CorporationSmart traffic signal system
US20050165537 *Mar 17, 2004Jul 28, 2005Dort David B.Externally activated non-negative acceleration system
US20050220538 *Jan 17, 2003Oct 6, 2005Van Der Poel Lucas L DRoad marking system
US20080199255 *Apr 1, 2008Aug 21, 2008Rhino Advertising Pty LimitedMethod of placing visible advertising
US20080216367 *Aug 18, 2004Sep 11, 2008Koninklijke Philips Electronics N.V.Road-Marking System
US20090047068 *Aug 15, 2008Feb 19, 2009Bucalo Louis RRoad Course and Methods of Use
US20090060647 *Sep 4, 2007Mar 5, 2009John DenisonTraffic merging system
US20110013981 *Jul 14, 2010Jan 20, 2011Larry E. BrownAnimal crossing warning zone and method of applying it to a roadway
WO1990012382A1 *Apr 11, 1990Oct 18, 1990The Marconi Company LimitedRoad traffic signalling system
U.S. Classification404/9, 340/932
International ClassificationE01F9/04, G08G1/16, G08G1/09
Cooperative ClassificationG08G1/096783, G08G1/096758, E01F9/04, G08G1/096716, G08G1/164
European ClassificationE01F9/04, G08G1/16B, G08G1/0967B3, G08G1/0967C2, G08G1/0967A1