Roadway shoulder rumble strips apparatus

Abstract

Rumble strips slow down the speed of tires that are crossing the rumble strips that the vehicle tends to turn its direction toward the shoulder. Also, a component of the reaction force from the rumble strips pushes the vehicle further away from its normal path. These two effects cause potential danger to the driver. The current invention shows a rumble strips apparatus that are capable of providing a guiding force to guide the vehicle back to its normal path and in the mean time, providing vibration as conventional rumble strips do.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] (Not Applicable)

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] (Not Applicable)

REFERENCE TO SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM LISTING COMPACT DISK APPENDIX

[0003] (Not Applicable)

BACKGROUND OF THE INVENTION

[0004] Rumble strips usually refer to a series of spaced, generally parallel grooves, depressions, or ribs in the surface of a roadway shoulder. Rumble strips can be created by cutting, grinding, or impressing the surface of the roadway in a pattern designed to alert the driver of a vehicle to a potential danger or change in conditions ahead. As used herein, the term roadway refers to the hard surface of a road or highway (including an interstate highway) that is intended for vehicular traffic. The term roadway shoulder refers to the edges of a roadway.

[0005] The use of rumble strips on the surface of the roadway shoulder is well known. As a vehicle's tires travel across the rumble strips on the surface of a roadway shoulder, a significant vibration is created which may be both felt and heard by the driver. However, rumble strips slow down the speed of tires that are crossing the rumble strips due to the resistance between the tires and the rough surface of the rumble strips. On the other hand, the speed of tires on the other side of the vehicle is not reduced. Therefore, under these unequal speeds, the vehicle tends to turn its direction toward the shoulder. Besides, a part of the reaction force from the rumble strips pushes the vehicle further away from its normal path. These two effects cause potential danger to the driver.

[0006] FIG. 1 shows a conventional rumble strips arrangement. In FIG. 1, the traffic in the rightmost (outer) travel lane 1 and the leftmost (inner) travel lane 2 are all moving in the same travel direction 4, which is toward the upper side of the paper. The rightmost travel lane 1 and the leftmost travel lane 2 are separated by a lane line 3. On the right of the rightmost travel lane 1 is a right edge line 12. On the right of the right edge line 12 is a right shoulder 13. In the right shoulder 13, there lies a plurality of rumble strips 14 which are substantial perpendicular to the right edge line 12. Similarly, on the left of the leftmost travel lane 2 is a left edge line 22. On the left of the left edge line 22 is a left shoulder 23. In the left shoulder 23, there lies a plurality of rumble strips 24 which are substantial perpendicularly to the left edge line 22.

[0007] The problems of the conventional rumble strips as shown in FIG. 1 can be illustrated in FIG. 2 and FIG. 3. In FIG. 2, a vehicle is traveling through the rightmost travel lane 1 in the direction of travel direction 4. When the vehicle is driving off road in a first position 15, shown in dotted line, where the vehicle is crossing the right edge line 12 and its right front wheel hit on the surface of the rumble strips 14, the vehicle is now in its first direction 17. Since the rough surface of the rumble strips 14 provide much more resistance than the regular road surface of the rightmost travel lane 1 does, the right side of the vehicle tends to slow down while the left side of the vehicle keep on its regular speed. These different speeds of the movement on different sides of the same vehicle cause the vehicle to turn toward the right shoulder 13. There is yet another problem. The rough surface of the rumble strips 14 provides a reaction force 170 back to the vehicle. The reaction force 170 has a direction perpendicular to the rumble strips 14. The reaction force 170 can be decomposed into a first component 170x and a second component 170y. Where the second component 170y has a direction opposite to the first direction 17 and therefore, it cancels out some force from the vehicle and reduce the speed on the right front wheel. On the other hand, the first component 170x is a force that has a direction to the right and is parallel to the rumble strips 14. The force of the first component 170x, therefore, pushes the vehicle further away from its normal travel direction 4. The vehicle is now in a second position 16 and a second direction 18 which is further away from its normal travel direction 4. Now both the right front wheel and the right rear wheel hit on the rumble strips 14. Rumble strips 14 provide even more resistance back to the right side of the vehicle that reduces more speed on the right side of the vehicle. The reactions force 180 provided by the rumble strips 14 have a first component 180x and a second component 180y. Where the second component 180y has a direction opposite to the second direction 18 and therefore, it cancels out some force from the vehicle and reduce the speed on the right wheels. On the other hand, the first component 180x has a direction to the right and is a force that is parallel to the rumble strips 14. Since the first component 180x is larger than the first component 170x due to a larger angle between the vehicle's direction and the perpendicular line of the rumble strips. The force of the first component 180x pushes the vehicle even further away from its normal travel direction 4. Before the driver take control of the wheel and turn it back to its normal path, the vehicle is driving toward a direction further away from its normal travel direction 4. We discovered that this change of direction is the side effect of the conventional rumble strips 14.

[0008] The side effects of the conventional rumble strips happens on the rightmost travel lane 1 also happens on the leftmost travel lane 2 only that it mirrors the corresponding parts. A reader should be able to understand the details shown in FIG. 3 by understanding the details described in the previous paragraph.

BRIEF SUMMARY OF THE INVENTION

[0009] It is an object of the present invention to provide a roadway shoulder rumble strips which is capable of providing a guiding force to guide the vehicle back to its normal path and in the mean time, providing vibration as conventional rumble strips do.

[0010] A rumble strips apparatus in the surface of a roadway shoulder is provided. Each of the rumble strip and the right edge line forms an angle of between 0 degree and 60 degrees. The reaction force from the rumble strips back to the vehicle can be decomposed into two components. Although one of the components is against the direction of the vehicle, the other component is a net force that pushes the vehicle back to its normal path.

[0011] In order to facilitate an understanding of the invention, the preferred embodiments of the invention are illustrated in the drawings, and a detailed description thereof follows. It is not intended, however, that the invention be limited to the particular embodiments described or to use in connection with the apparatus illustrated herein.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG. 1 is a conventional rumble strips.

[0013] FIG. 2 shows the direction change on the rightmost lane on conventional rumble strips.

[0014] FIG. 3 shows the direction change on the leftmost lane on conventional rumble strips.

[0015] FIG. 4 is the rumble strips of the current invention.

[0016] FIG. 5 illustrates the reaction force of the current invention.

[0017] FIG. 6 is another example of the current invention.

DETAILED DESCRIPTION OF THE INVENTION

[0018] The present invention provides a modified rumble strips apparatus that is illustrated in FIG. 4 and FIG. 5. In FIG. 4, the traffic in the rightmost (outer) travel lane 1 and the leftmost (inner) travel lane 2 are all moving in the same travel direction 4, which is toward the upper side of the paper. The rightmost travel lane 1 and the leftmost travel lane 2 are separated by a lane line 3. On the right of the rightmost travel lane 1 is a right edge line 12. On the right of the right edge line 12 is a right shoulder 13. In the right shoulder 13, there lies a plurality of rumble strips 34. A plurality of rumble strips 34 and the right edge line 12 forms an angle of about 45 degrees. Similarly, on the left of the leftmost travel lane 2 is a left edge line 22. On the left of the left edge line 22 is a left shoulder 23. In the left shoulder 23, there lies a plurality of rumble strips 44. A plurality of rumble strips 44 and right edge line 22 forms an angle of about 45 degrees.

[0019] Now let's investigate what happen when the vehicle is driving off road as shown in FIG. 5. In FIG. 5, a vehicle is in a first position 35, shown in dotted line, where the vehicle has across the right edge line 12 and its right front wheel hit on the surface of rumble strips 34. Since the rumble strips 34 provide much more resistance than regular road surface of the rightmost travel lane 1 provides, the right side of the vehicle tends to slow down while the left side of the vehicle keep on the regular speed as the conventional rumble strips do. However, since the rumble strips 34 and the right edge line 12 forms an angle of about 45 degrees. The reaction force 370 is in a direction perpendicular to the rumble strips 34. The reaction force 370 can be decomposed into a first component 370x and a second component 370y. Where the second component 370y has a direction opposite to the first direction 37 and therefore, it cancels out some force from the vehicle and reduce the speed on the right front wheel. However, the first component 370x is a force that is direct to the left and therefore, pushes the vehicle back to its normal travel direction 4.

[0020] Again, a reader should be able to understand the details on the leftmost travel lane 2 by understanding the details described in the previous paragraph.

[0021] There are other species of this invention. FIG. 6 shows an example of other embodiments. In FIG. 6, the rumble strips 54a, 54b, 64a, and 64b are all curve lines. However, for each of the rumble strips, the two ends of a rumble strip form a virtual line. This virtual line and the edge line 12 (22 for 64a and 64b) still form an angle of about 45 degrees. Therefore, for each rumble strip, some segments provide a larger reaction force component than other segments in the same rumble strip. However, when a vehicle hits on the rumble strips 54a, 54b, 64a, or 64b, the vehicle still get a reaction force component that pushes the vehicle back to its normal travel direction.

[0022] Although the description above shows that the rumble strips and the edge line form an angle of about 45 degrees, the angle can be of any value between 0 degree and 60 degrees. Usually, when a vehicle is driving off road, the vehicle's longitudinal axis and the edge line form an angle of at most 30 degrees. Therefore, as long as the angle formed by the rumble strips and the edge line is less than 60 degrees, one of the reaction force components will direct the vehicle back to its normal direction.

[0023] Various modifications and alternative embodiments such as would ordinarily occur to one skilled in the art to which the invention relates are also contemplated and included within the scope of the invention described and claimed herein.

Claims

1. (cancelled)

2. (cancelled)

3. (cancelled)

4. (cancelled)

5. A roadway shoulder rumble strips comprising:

a rightmost travel lane;

a right edge line lies on the right of said rightmost travel lane;

a right shoulder located on the right of said right edge line; and

a plurality of curved rumble strips lies in the said right shoulder

where the two ends of each of said plurality of curved rumble strips form a virtual line and the said virtual line and said right edge line form an angle of approximately 5-15°.

6. An apparatus as in claim 5, where the most part of each of the said curved rumble strips are on the left side of each of the said virtual line.

7. An apparatus as in claim 5, where the most part of each of the said curved rumble strips are on the right side of each of the said virtual line.

8. A roadway shoulder rumble strips comprising:

a leftmost travel lane;

a left edge line lies on the left of said leftmost travel lane;

a left shoulder located on the left of said left edge line; and

a plurality of curved rumble strips lies in the said left shoulder

where the two ends of each of said plurality of curved rumble strips form a virtual line and the said virtual line and said left edge line form an angle of approximately 5-15°.

9. An apparatus as in claim 8, where the most part of each of the said curved rumble strips are on the right side of each of the said virtual line.

10. An apparatus as in claim 8, where the most part of each of the said curved rumble strips are on the left side of each of the said virtual line.