Network of Traffic Behavior-monitoring Unattended Ground Sensors (NeTBUGS)

• US 20110050461A1
• Filed: 08/26/2009
• Published: 03/03/2011
• Est. Priority Date: 08/26/2009
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Harding, Martt, Pixley, Michael D.
• Granted Patent: US 8,368,559 B2
• Time in Patent Office: Days
• US Class Current: 340/933
• CPC Class Codes: G08G 1/0104 Measuring and analyzing of parameters relative to traffic conditions
• CPC Class Codes: G08G 1/056 with provision for distinguishing direction of travel

Abstract

A Network of Traffic Behavior-monitoring Unattended Ground Sensors (NeTBUGS) is configurable to detect the passing of vehicles, determine when and where individual vehicles have stopped for a period of time that raises suspicion of illegal or dangerous activity, track the vehicles after the stop and to generate a location-tagged alert for the timely dispatch of a response asset to investigate the anomalous behavior of the vehicle. NeTBUGS sensors are small, camouflaged, easily concealed, and operate for long durations independent of the electrical grid or large, obvious power generators and thus well suited for operation in a hostile environment.

Claims

1. A network of traffic behavior-monitoring unattended ground sensors, comprising:

a plurality of autonomously-powered sensor nodes in an ordered network, each said sensor node having a programmable power management mode including standby and operations times corresponding to high and low-density traffic behavior, respectively, each said sensor node configured during operations to detect the time and direction of travel of a passing vehicle and broadcast via a communication link a detection message including a node identifier, the detection time and the direction and to receive detection messages from adjacent nodes, each said sensor node operating in a delay mode in which upon passing of a specified time increment from the detection time reported by the adjacent node without detecting the passage of the anticipated vehicle broadcasts an alert delay message including a node identifier, an alert time of vehicle non-arrival and the direction of travel via the communication link, and

a control station including a computer configured to receive alert delay messages and, knowing the topology of the ordered network and the geolocation of each said sensor node, to facilitate timely dispatch of an asset to investigate the anomalous behavior of the vehicle.

2. The network of claim 1, wherein said plurality of sensor nodes are placed at most 500 meters apart along a monitored road.

3. The network of claim 2, wherein said plurality of sensor nodes are placed on the same side of the monitored road.

4. The network of claim 1, further comprising:

at least one autonomously-powered relay node configured to receive alert delay messages from sensor nodes via a local communication link and to rebroadcast the alert delay messages via a remote communication link to the control station.

5. The network of claim 1, wherein said sensor node comprises at least one sensor configured to sense passing vehicles with all degrees of freedom of rotation alignment.

6. The network of claim 1, wherein said sensor node comprises at least one sensor configured to sense passing vehicles with at least one degree of freedom of rotation alignment and at least one constrained degree of freedom of rotation alignment, said sensor node further comprising means to orient the node to satisfy said at least one constrained degree of freedom.

7. The network of claim 6, wherein said node includes an alignment axis, said means configured to orient the node so that the alignment axis lies approximately perpendicular to a surface on which the node is placed, said node including a plurality of sensors positioned around the axis so that the node is insensitive to rotation about the alignment axis.

8. The network of claim 1, wherein said sensor node comprises an acoustic or seismic vibration sensor and a magnetic sensor, which together detect the passing vehicle.

9. The network of claim 1, wherein the control station broadcasts control messages to the network of sensor nodes, said control messages including the times for the sensor nodes'"'"' power management mode.

10. The network of claim 1, wherein the specified time increment is an expected time increment plus a delay time increment.

11. The network of claim 10, wherein said network of sensor nodes has a calibration mode in which the nodes gathers statistics on the time increments of vehicles passing adjacent nodes in the network to determine the expected time increments for each said sensor node.

12. The network of claim 11, wherein the delay time increment is one of a fixed multiplier of the expected time increment, a fixed and possibly fractional number of standard deviations beyond the expected time increment, a threshold vehicle stop time or a delay calibrated to a specified nuisance alarm rate.

13. The network of claim 12, wherein the control station broadcasts control messages to the network of sensor nodes, said control messages including the delay time increment.

14. The network of claim 10, wherein the detection message includes a history of actual time increments for the passing vehicle as it travels through the network, said sensor node modifying the expected time increments based on the history to trigger the alert delay message for that passing vehicle.

15. The network of claim 1, wherein the control station broadcasts control messages to the network of sensor nodes, said control messages including the specified time increments.

16. The network of claim 1, wherein the detection message includes a history of actual time increments for the passing vehicle, said sensor node modifying the specified time increments based on the history to trigger the alert delay message for that passing vehicle.

17. The network of claim 1, wherein the sensor node periodically broadcasts the alert delay message until the node either detects the passing vehicle or times out.

18. The network of claim 1, wherein said sensor nodes have a detection mode in which the detection message is broadcast as an alert detection message that is received by the control station.

19. The network of claim 18, wherein the sensor node only broadcasts the alert detection message if the density of the number of passing vehicle detections over a specified unit of time exceeds a threshold.

20. The network of claim 18, wherein the control station broadcasts control messages to the network of sensor nodes, said control messages including a message to enable or disable detection mode.

21. The network of claim 18, wherein said sensor nodes have a track mode in which if a sensor node broadcasts an alert delay message at least the sensor nodes in the vicinity of that sensor node enable the detection mode and generate alert track messages upon detecting the vehicle.

22. The network of claim 21, wherein the control station dispatches an unmanned aerial vehicle to acquire and truck the vehicle.

23. The network of claim 1, wherein the control station dispatches the response asset to acquire and track the vehicle.

24. The network of claim 23, wherein the response asset is an unmanned aerial vehicle.

25. The network of claim 23, wherein the control station dispatches another response asset to verify the location where the vehicle stopped.

26. The network of claim 1, wherein each said node includes a geolocation receiver for measuring the geolocation of the node, said node sending a message to the control station including its geolocation.

27. The network of claim 26, wherein after emplacement said node periodically measures its geolocation, if said node detects that it has moved the node broadcasts an alert tamper message.

28. The network of claim 1, further comprising:

a vehicle for delivering the sensor nodes;

a deployment mechanism for deploying the nodes along the side of a road;

a geolocation device for recording the geolocation of each sensor node as it is deployed;

a test mechanism for interacting with each sensor node immediately after deployment to determine the node'"'"'s readiness for service; and

a mechanism to alert a following vehicle to deploy a replacement sensor in approximately the same location as a failed sensor node.

29. The network of claim 28, wherein the geolocation of each sensor node is downloaded to the control station and broadcast to the sensor nodes so that each node is aware of its own geolocation.

30. The network of claim 1, wherein the node includes a plurality of sensors to detect passing vehicles at different orientations to the node, said node configured to determine the direction of the passing vehicle from the detection responses of said plurality of sensors and the sensor node'"'"'s position in the network topology.

31. The network of claim 1, where said node is configured to determine the direction of the passing vehicle from the ordered network topology and the detection message received from an adjacent node.

32. The network of claim 1, wherein the control station broadcasts sequential node identifier to the sensor nodes to define the ordered network.

33. A network of traffic behavior-monitoring unattended ground sensors, comprising:

a plurality of autonomously-powered remotely-programmable sensor nodes in an ordered network, each said sensor node having a geolocation receiver for measuring the geolocation of the node, each said node broadcasting its geolocation and operational status and receiving a node-identification number, each said sensor node having a power management mode including standby and operations times corresponding to high and low-density traffic behavior, respectively, each said sensor node configured during operations to detect the time and direction of travel of a passing vehicle and broadcast via a communication link a detection message including a node identifier, the detection time and the direction of vehicle travel and to receive detection messages from adjacent nodes, each said sensor node remotely programmable to operate in (a) an alert detection mode in which the detection messages are broadcast as alert detection messages, (b) a delay mode in which upon passing of an expected time increment plus a delay time increment from the detection time reported by the adjacent node without detecting the passage of the anticipated vehicle said sensor node broadcasts an alert delay message including a node identifier, an alert time of non-arrival and the direction of travel via the communication link and (c) a track mode in which upon broadcast of an alert delay message at least the sensor nodes in the vicinity of that sensor node enable alert detection mode; and

a control station including a computer configured to receive the geolocation and operational status of each said sensor node and to broadcast the node-identification numbers, said control station configured to receive alert detection messages and alert delay messages and knowing the topology of the ordered network and the geolocation of each said sensor node to facilitate timely dispatch an asset to investigate the anomalous behavior of the vehicle.

34. The network of claim 33, wherein the sensor nodes comprise an audio or seismic vibration sensor and a magnetic sensor to detect the passing vehicles.

35. The network of claim 33, wherein said network of sensor nodes has a calibration mode in which the network gathers statistics on the time increments of vehicles passing adjacent nodes in the network to determine the expected time increments for each said sensor node, said delay time increment selected from one of a fixed multiplier of the expected time increment, a fixed and possibly fractional number of standard deviations beyond the expected time increment, a threshold vehicle stop time or to satisfy a specified nuisance alarm rate.

36. The network of claim 33, wherein the detection message includes a history of actual time increments for the passing vehicle, said sensor node modifying the expected time increments based on the history to trigger the alert delay message for that passing vehicle.

37. The network of claim 36, wherein the control station broadcasts control messages to the network of sensor nodes, said control messages specifying the delay time increment.