System and synchronization process for inductive loops in a multilane environment

• US 7,764,197 B2
• Filed: 01/28/2008
• Issued: 07/27/2010
• Est. Priority Date: 10/17/2001
• Status: Expired due to Term

• Current Assignee: Transcore LP (Roper Technologies, Inc.)
• Original Assignee: United Toll Systems, Inc.
• Inventors: Allen, David C. Sr., Jacobs, Allen, Banna, Balaraju, Allen, Jim, Talley, Malcolm
• Primary Examiner(s): Mullen; Thomas J
• Application Number:
  US12/020,661
• Publication Number:
  US 20080143555A1
• Time in Patent Office: 911 Days
• Field of Search: 340/939, 340/941, 705/13
• US Class Current: 340/933
• CPC Class Codes: G08G 1/01 Detecting movement of traffic to be counted or controlled G08G1/07 - G08G1/14 take precedence
• CPC Class Codes: G08G 1/0175 by photographing vehicles, e.g. when violating traffic rules
• CPC Class Codes: G08G 1/042 using inductive or magnetic detectors

Abstract

A method and system for synchronization of detection loops in a multilane environment. A plurality of loop sensors are arranged in a plurality of lanes such that loop sensors in adjacent lanes are mutually contiguous. A simultaneous synchronization signal is sent to each of the plurality of loop detector controllers, where each loop detector controller is in communication with a loop sensor. The signal causes a scheduling of sampling periods for each loop sensor, such that the sampling period of each loop sensor does not overlap with that of a contiguous loop in an adjacent lane.

Claims

1. A system for managing a multi-lane road, comprising:

a plurality of vehicle detection sensors arranged on two or more lanes of the road so that each of the two or more lanes of the road contains at least one of the plurality of vehicle detection sensors, the vehicle detection sensors further arranged so that like sensors in adjacent lanes are mutually adjacent to each other;

a plurality of loop detector controllers each associated with one of the two or more lanes of the road, wherein each of the plurality of loop detector controllers is configured to control sampling periods of one or more of the vehicle detection sensors; and

a communications master controller configured to transmit one or more synchronization signals to the plurality of loop detector controllers that cause the plurality of loop detector controllers to synchronize the sampling periods of the plurality of vehicle detection sensors such that a given vehicle detection sensor samples substantially in unison with one or more other vehicle detection sensors that are not adjacent to the given vehicle detection sensor, and such that none of the vehicle detection sensors adjacent to the given vehicle sensor actively sample while the given vehicle detection sensor is actively sampling.

2. The system of claim 1, wherein one or more of the vehicle detection sensors are inductive loop sensors.

3. The system of claim 1, wherein the communications master controller is configured to transmit the synchronization signals periodically at intervals greater than the sampling periods of the vehicle detection sensors.

4. The system of claim 1, wherein the synchronization signals are sent to each loop detector controller on a predetermined time schedule.

5. The system of claim 4, wherein the predetermined time schedule corresponds to one of a single instance at the start up of all the lanes and a regular interval that is between about 1 seconds and about 60 seconds.

6. The system of claim 1, wherein the communications master controller is configured to provide a control interface that displays a schematic layout of a position and sensor primary and secondary sampling period status of each of the plurality of vehicle detection sensors.

7. The system of claim 6, wherein the schematic layout comprises an X-Y grid, and wherein sensor primary and secondary sampling period status comprises a substantially checkerboard pattern.

8. The system of claim 7, wherein each position on the checkerboard pattern oscillates from primary to secondary sampling period in a synchronized manner.

9. A method for intelligent vehicle identification, comprising:

sending a synchronization signal to two or more loop detector controllers, wherein each loop detector controller is configured to control one or more of a plurality of vehicle detection sensors; and

scheduling a sampling period for each vehicle detection sensor such that a given vehicle detection sensor samples substantially in unison with one or more other vehicle detection sensors that are not adjacent to the given vehicle detection sensor, and such that none of the vehicle detection sensors adjacent to the given vehicle sensor actively sample while the given vehicle detection sensor is actively sampling.

10. The method of claim 9, wherein one or more of the vehicle detection sensors are inductive loop sensors.

11. The method of claim 9, wherein sending the synchronization signal comprises transmitting the synchronization signal periodically at intervals greater than the sampling periods of the vehicle detection sensors.

12. The method of claim 9, wherein the synchronization signal is sent once during start up of all the plurality of lanes.

13. The method of claim 9, wherein the synchronization signal is sent at a regular interval of between about 1 second and about 60 seconds.

14. A system for managing a multi-lane toll road, comprising:

a plurality of vehicle detection sensors arranged on two or more lanes of a multi-lane toll road,

wherein the vehicle detection sensors operate in a periodic manner according to a sampling period such that each sampling period includes a primary sampling period and a secondary sampling period, and wherein during a primary sampling period for a given vehicle detection sensor the given vehicle detection sensor is active and during a secondary sampling period for the given vehicle detection sensor the given vehicle detection sensor is inactive, and

wherein the plurality of vehicle detection sensors comprise;

a first vehicle detection sensor arranged on a first lane of the toll road;

a second vehicle detection sensor arranged on a second lane of the toll road at a position adjacent the first vehicle detection sensor;

a third vehicle detection sensor arranged on the first lane of the toll road at a position adjacent the first vehicle detection sensor but not adjacent the second vehicle detection sensor; and

a fourth vehicle detection sensor arranged on the second lane of the toll road at a position adjacent the second vehicle detection sensor and the third vehicle detection sensor but not adjacent the first vehicle detection sensor;

one or more loop detector controllers configured to control the sampling periods of the plurality of vehicle detection sensors; and

a communications master controller communicatively linked with the one or more loop detector controllers, the communications master controller being configured to transmit a synchronization signal to the one or more loop detector controllers,

wherein the one or more loop detector controllers are further configured to synchronize the sampling periods of the plurality of vehicle detection sensors based on the synchronization signal transmitted by the communications master controller such that (i) the primary sampling periods of the first vehicle detection sensor and the fourth vehicle detection sensor occur substantially simultaneously during the secondary sampling periods of the second vehicle detection sensor and the third vehicle detection sensor, and (ii) the primary sampling periods of the second vehicle detection sensor and the third vehicle detection sensor occur substantially simultaneously during the secondary sampling periods of the first vehicle detection sensor and the fourth vehicle detection sensor.

15. The system of claim 14, wherein the vehicle detection sensors comprise at least one inductive loop sensor.

16. The system of claim 14, wherein the communications master controller is configured to transmit the synchronization signal periodically at intervals greater than the sampling periods of the plurality of vehicle detection sensors.

17. The system of claim 14, wherein the synchronization signal is sent to each loop detector controller on a predetermined time schedule.

18. The system of claim 17, wherein the predetermined time schedule corresponds to one of a single instance at the start up of all the lanes and a regular interval that is between about 1 second and about 60 seconds.

19. A method for intelligent vehicle identification on a toll road, comprising:

sending a synchronization signal to two or more loop detector controllers, wherein each loop detector controller is configured to control one or more of a plurality of vehicle detection sensors arranged on two or more lanes of a multi-lane toll road,

wherein the plurality of vehicle detection sensors comprise;

a first vehicle detection sensor arranged on a first lane of the toll road;

a second vehicle detection sensor arranged on a second lane of the toll road at a position adjacent the first vehicle detection sensor;

a third vehicle detection sensor arranged on the first lane of the toll road at a position adjacent the first vehicle detection sensor but not adjacent the second vehicle detection sensor; and

a fourth vehicle detection sensor arranged on the second lane of the toll road at a position adjacent the second vehicle detection sensor and the third vehicle detection sensor but not adjacent the first vehicle detection sensor; and

synchronizing sampling periods of the plurality of vehicle detection sensors based on the synchronization signal,

wherein the sampling period of a given vehicle detection sensor includes a primary sampling period during which the given vehicle detection sensor is active and a secondary sampling period during which the given vehicle detection sensor is inactive, and

wherein synchronizing the sampling periods of the plurality of vehicle detection sensors comprises controlling the sampling periods of the first vehicle detection sensor, the second vehicle detection sensor, the third vehicle detection sensor, and the fourth vehicle detection sensor such that (i) the primary sampling periods of the first vehicle detection sensor and the fourth vehicle detection sensor occur substantially simultaneously during the secondary sampling periods of the second vehicle detection sensor and the third vehicle detection sensor, and (ii) the primary sampling periods of the second vehicle detection sensor and the third vehicle detection sensor occur substantially simultaneously during the secondary sampling periods of the first vehicle detection sensor and the fourth vehicle detection sensor.

20. The method of claim 19, wherein one or more of the vehicle detection sensors are inductive loop sensors.

21. The method of claim 19, wherein all of the vehicle detection sensors are inductive loop sensors.

22. The method of claim 19, wherein the synchronization signal is sent once during start up of an intelligent vehicle identification system performing the method for intelligent vehicle identification.

23. The method of claim 19, wherein the synchronization signal is sent at a regular interval of between about 1 seconds and about 60 seconds.

24. The method of claim 19, wherein the synchronization signal is based on a phase of a common power supply that provides power to each of the vehicle detection sensors.