Apparatus and method for measuring vehicle speed and/or acceleration

• US 6,750,444 B2
• Filed: 05/02/2001
• Issued: 06/15/2004
• Est. Priority Date: 12/29/2000
• Status: Expired due to Fees

• Current Assignee: GSLE Subco, LLC (SPX Corporation)
• Original Assignee: SPX Corporation
• Inventors: Kyle, Paul F., DiDomenico, John, Rendahl, Craig S.
• Primary Examiner(s): Luu, Thanh X.
• Application Number:
  US09/846,375
• Publication Number:
  US 20030122065A1
• Time in Patent Office: 1,140 Days
• Field of Search: 250/231.1, 250/221, 250/206.1, 356/28, 180/167-169, 340/936, 340/942
• US Class Current: 250/231.1
• CPC Class Codes: G01P 3/68 using optical means, i.e. using infrared, visible, or ultraviolet light G01P3/80 takes precedence ; by reflection of waves G01S17/58
• CPC Class Codes: G08G 1/052 with provision for determining speed or overspeed speed measuring in general G01P

Abstract

An apparatus and method for measuring the speed and/or acceleration of a vehicle traveling on a vehicle path includes sender/detector units on one side of the vehicle path and corresponding retro-reflector matrix units on the other side of the vehicle path. A controller calculates speed and/or acceleration of the vehicle in response to interruption of the beam by a passing vehicle.

Claims

1. An apparatus for measuring at least one of a speed and acceleration of a vehicle traveling on a vehicle path, the apparatus comprising;

a first radiation source that emits radiation arranged at a first side of the vehicle path;

a first reflector arranged on a second, opposite side of the vehicle path from said first radiation source that reflects radiation emitted from said first radiation source back towards the first side of the vehicle path;

a first detector arranged at the first side of the vehicle path that receives the reflected radiation from said first reflector and detects a presence and absence of the reflected radiation;

a second radiation source that emits radiation arranged at the first side of the vehicle path;

a second reflector arranged on the second, opposite side of the vehicle path from said second radiation source that reflects radiation emitted from said second radiation source back towards the first side of the vehicle path.

a second detector arranged at the first side of the vehicle path that receives the reflected radiation from said second reflector and detects a presence and absence of the reflected radiation;

a controller operatively connected to said first and second detectors that calculates at least one of the speed and acceleration of the vehicle in response to said first and second detectors; and

a tilt sensor that measures a tilt of the vehicle path relative to a level path, wherein said controller determines Vehicle Specific Power of the vehicle due to calculated acceleration and measured tilt;

wherein each said radiation source is a modulated laser beam source.

2. An apparatus according to claim 1, wherein said first radiation source and said first detector are located in a first sender detector unit, and wherein said second radiation source and said second detector are located in a second sender detector unit.

3. An apparatus according to claim 1, wherein said first reflector and second reflector comprise first and second retro-reflective matrix units. respectively.

4. An apparatus according to claim 2, further comprising a bar unit, wherein said first and second sender detector units are each supported on said bar unit.

5. An apparatus according to claim 4, further comprising at least two bar units, each supporting at least a pair of said sender detector units, and spaced apart from each other at a desired interval.

6. An apparatus according to claim 4, further comprising at least two bar units, each supporting at least a pair of sender detector units, and connected to each other end to end.

7. An apparatus according to claim 2, wherein said first and second sender detector units are each affixed into a permanent installation on a first side of the vehicle path.

8. An apparatus according to claim 7, wherein a plurality of pairs of first and second sender detector units are affixed into a permanent roadside installation spaced apart at desired intervals.

9. An apparatus according to claim 3, wherein said first and second reflectors are each affixed into a permanent installation on a second, opposite side of the vehicle path.

10. An apparatus according to claim 9, wherein a plurality of pairs of first and second reflectors are affixed into a permanent roadside installation spaced apart at desired intervals.

11. An apparatus according to claim 1, wherein the modulated laser beam source modulates a beam at a rate greater than approximately 20 kHz.

12. An apparatus for measuring at least one of a speed and acceleration of a vehicle traveling on a vehicle path, the apparatus comprising:

first radiation means for emitting radiation arranged at a first side of the vehicle path;

first reflector means arranged on a second, opposite side of the vehicle path from said first radiation means for reflecting radiation emitted from said first radiation means back towards the first side of the vehicle path;

first detector means arranged at the first side of the vehicle path that receives the reflected radiation from said first reflector means for detecting a presence or absence of the reflected radiation;

second radiation means for emitting radiation arranged at the first side of the vehicle path;

second reflector means arranged on the second, opposite side of the vehicle path from said second radiation means for reflecting radiation emitted from said second radiation means back towards the first side of the vehicle path;

second detector means arranged at the first side of the vehicle path that receives the reflected radiation from said second reflector means for detecting a presence or absence of the reflected radiation;

calculating means operatively connected to said first and second detectors, for calculating at least one of the speed and acceleration of the vehicle in response to said first and second detectors; and

measuring means for measuring a tilt of the vehicle path relative to a level path; and

determining means for determining a Vehicle Specific Power of the vehicle due to the calculated acceleration based in part on the measured tilt;

wherein each of said radiation means comprises means for modulating radiation to emit a modulated beam.

13. A method according to claim 12, wherein the first and second radiation and detector means are each affixed to a permanent installation on the side of the roadway.

14. A method according to claim 12, wherein a first and second reflector means are each affixed to a permanent installation on the side of the roadway.

15. A method for measuring at least one of a speed and acceleration of a vehicle traveling on a vehicle path, the method comprising the steps of;

emitting radiation from a first side of the vehicle path;

reflecting radiation emitted from said radiation emitting step at a second, opposite side of the vehicle path back towards the first side of the vehicle path;

receiving at the first side of the vehicle path the reflected radiation from the reflecting step;

detecting a presence or absence of the reflected radiation;

calculating at least one of the speed and acceleration of the vehicle in response to the detecting step;

measuring a tilt of the vehicle path relative to a level path; and

determining a Vehicle Specific Power of the vehicle due to the calculated acceleration based in part on the measured tilt;

wherein the emitting step comprises the step of modulating radiation to emit a modulated beam.

16. A method according to claim 15, wherein the step of modulating the beam includes modulating the beam at a rate between approximately 20 kHz and approximately 200 kHz.

17. A method according to claim 15, wherein the reflecting step includes reflecting using a retro-reflective matrix unit.

18. An apparatus for measuring at least one of a speed and acceleration of a vehicle traveling on a vehicle path, the apparatus comprising;

means for emitting radiation from a first side of the vehicle path;

means for reflecting radiation emitted from said radiation emitting step at a second, opposite side of the vehicle path back towards the first side of the vehicle path;

means for receiving at the first side of the vehicle path the reflected radiation from the reflecting step;

means for detecting a presence or absence of the reflected radiation; and

means for calculating at least one of the speed and acceleration of the vehicle in response to the detecting step;

means for measuring a tilt of the vehicle path relative to a level path; and

means for determining a Vehicle Specific Power of the vehicle due to the calculated acceleration based in part on the measured tilt;

wherein each of said emitting means comprises means for modulating radiation to emit a modulated beam.