U.S. patent number 3,559,756 [Application Number 04/805,637] was granted by the patent office on 1971-02-02 for wrong way traffic control system.
Invention is credited to Noel M. Torres.
United States Patent |
3,559,756 |
Torres |
February 2, 1971 |
WRONG WAY TRAFFIC CONTROL SYSTEM
Abstract
The system is adaptable to vehicles having radiant energy
proximity detecting or automatic spacing apparatus. A series of
fixed radiant energy reflectors is placed along the side of a
one-way traffic lane to reflect signals back to a wrong way vehicle
and warn or stop the vehicle. A simple addition to the basic
proximity detecting apparatus locks the brakes until the vehicle is
reversed.
Inventors: |
Torres; Noel M. (San Diego,
CA) |
Family
ID: |
25192079 |
Appl.
No.: |
04/805,637 |
Filed: |
March 10, 1969 |
Current U.S.
Class: |
180/169; 342/71;
340/935 |
Current CPC
Class: |
G08G
1/056 (20130101); G08G 1/075 (20130101) |
Current International
Class: |
G08G
1/07 (20060101); B60t 007/12 (); G01s 009/02 ();
B60k 077/08 () |
Field of
Search: |
;180/98 ;340/32,53
;343/7ED |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Bennett, Jr.; Rodney D.
Assistant Examiner: Tubbesing; T. H.
Claims
I claim:
1. Wrong way traffic control means for a vehicle having a gear
shift, brake-actuating means, and radiant energy means for
detecting the proximity of a reflective object ahead and
controlling the progress of the vehicle in response thereto,
including operation of the vehicle brakes, the traffic control
means comprising; a plurality of radiant energy reflectors spaced
along a one way traffic lane with reflective front surfaces
oriented to reflect radiant energy to a wrong way vehicle.
2. Means according to claim 1, wherein said reflectors have
substantially nonreflective rear surfaces.
3. Means according to claim 1, wherein said reflective front
surfaces are nonplanar.
4. Means according to claim 1, wherein said reflectors are
substantially wedge shaped in cross section, with a minimum surface
area presented to right way traffic.
5. Means according to claim 1, wherein said reflectors are spaced
to reflect the radiant energy in rapidly successive pulses as the
vehicle advances; said traffic control means including
pulse-counting means on said vehicle coupled to said radiant energy
means to operate said brake actuating means after a predetermined
number of pulses of reflected energy.
6. Means according to claim 5, and including resetting means
coupled to said pulse-counting means and being operable by said
gear shift to release the brakes upon reversing the vehicle.
Description
BACKGROUND OF THE INVENTION
The present invention relates to traffic control and specifically
to a wrong way traffic control system.
Due to increasing traffic density and the complexities of highways
wrong way driving is becoming more frequent and is extremely
dangerous. Various means have been proposed to prevent wrong way
driving, in addition to the usual signs, but all have some
disadvantages. The simple types, such as spikes, blades, physical
barriers and the like, usually disable the wrong way vehicle and
leave it blocking the traffic lane, and this can be dangerous to
right way traffic.
SUMMARY OF THE INVENTION
The system described herein is for use with vehicles having radiant
energy proximity detecting or automatic spacing apparatus. Various
types of such apparatus have been proposed tested and will almost
certainly come into common use as a primary safety feature for high
speed travel in heavy traffic. With this type of apparatus a beam
of radiant energy is transmitted ahead and is reflected from the
preceding vehicle, the range being automatically computed and
control means actuated to inform the driver or to actually control
the vehicle, so that spacing is adjusted to a safe distance in
relation to speed.
The wrong way indicating part of the system comprises fixed radiant
energy reflectors spaced along a one way traffic lane to reflect
strong signals to a wrong way vehicle and cause a warning or actual
stopping of the vehicle by its own means. The cost of the reflector
installation is low and very little maintenance is required. A
simple addition to the basic proximity detection apparatus is
actuated by repetitive pulses from successive spaced reflectors, to
hold the vehicle brakes on until the vehicle is reversed, so
preventing further travel in the wrong direction.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a diagram of a typical highway interchange with the
reflectors installed;
FIG. 2 is a front elevation view of a typical reflector;
FIG. 3 is an enlarged sectional view taken on line 3-3 of FIG.
2;
FIGS. 4--6 are sectional views similar to FIG. 3, showing
alternative reflector configurations; and
FIG. 7 is a schematic diagram of the modified proximity detection
apparatus used in the vehicle.
DESCRIPTION THE PREFERRED EMBODIMENTS
Since many accidents on busy highways are compounded because
vehicles are too closely spaced and unable to stop in time, it has
been recognized that efficient control of vehicle spacing is an
essential factor in improving traffic safety. Various systems have
been proposes, and some tested, which control vehicles
automatically by equipment in the vehicles, or in the roads, or
both, the road-installed systems being expensive. The most feasible
type utilizes a radiant energy transmitter and reciever in the
vehicle to measure the distance to the preceding vehicle, and
either indicate the same to the driver or actually control the
vehicle to maintain safe spacing in accordance with speed. Such
apparatus can use radar, laser, infrared, or other radiant energy
means, and the system described herein is adaptable to all types.
For reference purposes, U.S. Pats. No. 2,804,160 and 3,011,580 show
radar and infrared systems, respectively, of the type
described.
Atypical proximity detecting system is shown in very simple form in
FIG. 7, in which a transmitter 10 transmits a beam of radiant
energy and a receiver 12 picks up returned energy from a reflective
object 14. If the distance to the reflector is less than a
predetermined safe minimum, the receiver causes a brake actuator 16
to operate the vehicles brakes and, if necessary, adjusts speed by
means of a throttle actuator 18. It is assumed that the apparatus
will incorporate a minimum signal threshold to prevent constant
reaction to spurious reflections from roadside obstacles and the
like.
In the arrangement shown in FIG. 1, a plurality of reflectors 20
are spaced along the outside edge of an off ramp 22 curving from a
primary divided highway 24 to a secondary road 26. Correct traffic
flow is indicated by outlined arrows and the direction of a wrong
way vehicle 28 by a solid arrow.
Each reflector 20 is supported on a post 30, or other suitable
means and has a highly reflective front face 32, which is shown as
being rectangular and elongated vertically to allow for variations
in the height of the radiant energy beam. The face 32 need not be
highly polished, merely a good reflector for infrared and laser
light. Making the reflector of metal will ensure a good return for
radar.
It will be seen that the radiant energy beam from vehicle 28 will
sweep around the outside of off ramp 22, and the reflectors are
oriented so that their faces 32 will be at the optimum angle to
reflect a strong signal back to the vehicle. To avoid operation of
the proximity detection of a right way vehicle, it is important
that a minumum area of the reflector is presented to the direction
of right way travel. In some road configurations a simple flat
plate reflector may suffice if the orientation is such that the
edge of the plate is presented to right way traffic. To accommodate
different road curvatures and arrangements, the reflector 20 may be
made generally wedge shaped in cross section, as in FIG. 2, and
oriented with the point of the wedge toward right way traffic. This
will present a minimum target area to radar and the rear face 34
may be treated to minimize optical reflectivity in any suitable
manner. In any event, in the arrangement shown, and in most other
instances, the orientation of the rear face 34 is such that the
radiant energy beam from a right way orientation vehicle will be
deflected to the side.
A set of reflectors 20 is also installed along the inside edge of
off ramp 22 adjacent road 26, to provide reflections to a vehicle
turning right from the right-hand lane of the secondary road. These
may cause the vehicle to be stopped immediately on entering the off
ramp and need not extend very far along the ramp, since the radiant
energy beam will be directed to the outside of the curve once the
vehicle is on the ramp.
In its basic form in FIG. 2, the reflector has a flat reflective
face 32. Since some of the radiant energy systems are necessarily
narrow beam, it may be desirable to vary the direction of
reflection over a certain area to ensured pickup by the receiver.
This is easily accomplished by making the reflective face
nonplanar. As examples, FIG. 4 shown a convex curved reflective
face 36, FIG. 5 shows the concave face 38 in one facet of a
multifaceted reflector and FIG. 6 a ribbed face 40. Other
configurations could be used for specific road layouts.
As the vehicle proceeds in the wrong direction, as in FIG. 1, the
radiant energy will be reflected to the receiver as a series of
pulses. The proximity of the reflectors will cause the detection
apparatus to slow the vehicle and make the driver aware of
impending danger. However, by making an addition to the basic
proximity detection apparatus, the pulsed reflections resulting
from the spaced reflectors can be utilized to stop the vehicle.
In FIG. 7, such an addition includes a pulse counter 42 connected
between the receiver 12 and brake actuator 16, in addition to the
existing connection, to cause the brakes to be applied after
receiving a predetermined number of rapidly successive signal
pulses. Pulse-counting switches of this type are well known in
industrial applications, such as automatic processing or material
handling, and can be set for many different pulse number and timing
situations. Operation of the brakes through the pulse counting part
of the system would override the speed control provided by the
basic system in response to substantially continuous small
fluctuations of the reflected signal.
To allow the vehicle to be moved after being stopped by the pulsed
signals, a normally closed resetting switch 44 is installed at a
convenient position in the circuit, such as between the pulse
counter and the brake actuator. Switch 44 is opened by an arm 46,
or comparable actuating means, on the gear shift lever 48, only
when the lever is moved to the reverse position. Thus the vehicle
is stopped and held by the brakes until shifted into reverse and
backed out of the off ramp 22. Any attempt to resume wrong way
forward motion after reversing will result in the vehicle being
stopped again by the pulsed signal.
In a complete installation a sign 50, or several signs, would be
placed at the outside of the off ramp to warn and instruct a wrong
way driver. The sign could be illuminated, either permanently or
triggered by approach of a wrong way vehicle. Certain of the
reflectors could also incorporate visual warning means to suit
specific road arrangements.
* * * * *