Harbor fence

• US 7,233,544 B1
• Filed: 11/03/2005
• Issued: 06/19/2007
• Est. Priority Date: 02/12/2003
• Status: Expired due to Term

• Current Assignee: Leidos, Inc. (Leidos Holdings, Inc.)
• Original Assignee: Science Applications International Corporation
• Inventors: McDonald, Larry R
• Primary Examiner(s): Lobo; Ian J.
• Application Number:
  US11/265,150
• Publication Number:
  US 20070133350A1
• Time in Patent Office: 593 Days
• Field of Search: 367/93, 367/136, 114/240.R, 114/240.D
• US Class Current: 367/93
• CPC Class Codes: B63G 2009/005 of sonic watch equipment, e.g. low-frequency or sonar
• CPC Class Codes: B63G 9/04 Nets or the like net barriers for harbour defence F41H11/00
• CPC Class Codes: G01S 15/04 Systems determining presence of a target
• CPC Class Codes: G01S 15/66 Sonar tracking systems
• CPC Class Codes: G01S 15/87 Combinations of sonar systems
• CPC Class Codes: G01S 15/876 Combination of several spaced transmitters or receivers of known location for determining the position of a transponder or a reflector G01S15/872 takes precedence
• CPC Class Codes: G01S 7/003 Transmission of data between radar, sonar or lidar systems and remote stations
• CPC Class Codes: G01S 7/529 Gain of receiver varied automatically during pulse-recurrence period for seismic signals G01V1/245
• CPC Class Codes: G01S 7/539 using analysis of echo signal for target characterisation; Target signature; Target cross-section
• CPC Class Codes: G01S 7/54 with receivers spaced apart

Abstract

Methods and apparatus determine if an intruder passes into a security zone that is associated with a waterfront asset. An embodiment of the invention provides a harbor fence system that is designed to be deployed in water around ships or other waterfront assets to serve as a line-of-demarcation in order to provide protection. The harbor fence system comprises a series of spars that protrude above the water surface and that are connected with an electrical computer with a telemetry subsystem. Each spar contains electronic sensors, e.g. water immersion sensors and accelerometers, and circuitry to detect an intrusion and to communicate the location of the intrusion to a computer control station. The embodiment also facilitates deploying and retrieving the harbor fence system. Additionally, the embodiment may also determine whether an underwater intruder is passing under a protective boundary, in which the harbor fence system interfaces to an underwater sonar sensor subsystem.

Claims

1. A system for protecting an asset that abuts a body of water, the system comprising:

a flotation component that maintains the system at essentially a surface of the body of water and that forms a security parameter capable of encompassing the asset;

a plurality of sensor elements positioned along the flotation component, wherein the plurality of sensor elements detects an intruder breaching the security perimeter of the system; and

a control unit that sends a command signal to the plurality of sensor elements and that receives a received signal when at least one of the plurality of sensor elements detects the intruder breaching the security perimeter, and wherein the control unit indicates a location of breaching.

2. The system of claim 1, wherein the plurality of sensor elements comprises an immersion sensor.

3. The system of claim 1, wherein the plurality of sensor elements comprises an acceleration-sensitive sensor.

4. The system of claim 3, wherein the acceleration-sensitive sensor is selected from a group consisting of an accelerometer and a hydrophone.

5. The system of claim 1, further comprising:

a mooring that anchors the flotation component in an approximate fixed position.

6. The system of claim 1, wherein the flotation component comprises a plurality of spars and wherein a first spar is connected to an adjacent spar with at least one connecting line.

7. The system of claim 6 wherein the at least one connecting line includes a primary cable, the primary cable providing electrical power and communication to the plurality of spars.

8. The system of claim 6, wherein the first spar comprises at least one sensor of the plurality of sensors, the at least one sensor detecting the intruder when the intruder passes through the security perimeter of the system at an approximate position of the first spar.

9. The system of claim 8, wherein the first spar further comprises:

an upper section;

a keel that attaches to the upper section; and

a counterweight that attaches to the keel and that provides stability to the first spar in the body of water.

10. The system of claim 9, wherein the keel retracts into the upper section.

11. The system of claim 1, further comprising:

an underwater sonar sensor subsystem that detects an underwater intruder, wherein the control unit receives the received signal when the underwater sonar sensor subsystem detects the underwater intruder.

12. The system of claim 1 wherein the plurality of sensors comprises a first sensor submerged in the body of water and a second sensor above the body of water.

13. The system of claim 12 wherein the plurality of sensor elements detects the intruder breaching the security perimeter if the first sensor is moved above the body of water.

14. The system of claim 13 wherein the plurality of sensor elements detects the intruder breaching the security perimeter if the second sensor is moved below the surface of the body of water.

15. The system of claim 12 wherein the plurality of sensor elements detects the intruder breaching the security perimeter if the first and the second sensors are submerged in the body of water.

16. The system of claim 12 wherein the plurality of sensor elements detects the intruder breaching the security perimeter if the first and the second sensor are above the body of water.

29. The system of claim 1 further comprising a reel for retrieving the flotation component by winding the flotation component onto the reel.

30. The system of claim 1 further comprising a plurality of strobe lights positioned along the flotation component, wherein the plurality of strobe lights provides a visible indication of the presence of the security perimeter.

17. A system for protecting an asset that abuts a body of water, the system comprising:

a flotation component that maintains the system at essentially a surface of the body of water;

a plurality of sensor elements positioned along the flotation component, wherein the plurality of sensor elements detects an intruder passing through a security perimeter of the system and comprises at least one immersion detector; and

a control unit that sends a command signal to the plurality of sensor elements and that receives a signal when at least one of the plurality of sensor elements detects the intruder passing through the security perimeter, and wherein the control unit provides a security status.

18. The system of claim 17 wherein the plurality of sensor elements comprises a first immersion detector submerged in the water and a second immersion detector above the water and wherein the intruder passing through the security perimeter is detected if the first immersion detector and the second immersion detector are both one of submerged in the water or above the water.

19. The system of claim 17 wherein the plurality of sensor elements further comprises an acceleration-sensitive sensor.

20. The system of claim 19 wherein the intruder passing through the security perimeter is detected if the acceleration-sensitive sensor detects excessive impact on the security perimeter.

21. The system of claim 19 wherein the acceleration-sensitive sensor detects when the intruder makes contact with the system at an approximate position of the acceleration-sensitive sensor.

22. A system for protecting an asset that abuts a body of water, the system comprising:

a flotation component that maintains the system at essentially a surface of the body of water, the flotation component forming at least a portion of a security perimeter and having a helical configuration;

a plurality of sensor elements positioned along the flotation component, wherein the plurality of sensor elements detects an intruder breaching the security perimeter of the system; and

a control unit that receives a signal when at least one of the plurality of sensor elements detects the intruder breaching the security perimeter, and wherein the control unit indicates a location of breaching.

23. The system of claim 22 wherein the flotation component comprises a plurality of sections, each section having a helix boom line configuration.

24. The system of claim 23 wherein each section of the plurality of sections is connected to an adjacent section at a mating connector.

25. The system of claim 23 wherein each section further comprises a mooring.

26. The system of claim 23 wherein each section further comprises at least one light along the helix boom line configuration.

27. The system of claim 26 wherein each section is transparent and wherein the at least one light is visible through the corresponding section.

28. The system of claim 22 wherein the flotation component further comprises a snubber cable.

31. A system for protecting an asset that abuts a body of water, the system comprising:

a flotation component that maintains the system at essentially a surface of the body of water;

a plurality of sensor elements positioned along the flotation component, wherein the plurality of sensor elements detects an intruder passing through a security perimeter of the system and comprises a receiver module for receiving a target echo comprising sonar reflection signals from a target; and

a control unit that receives a signal when at least one of the plurality of sensor elements detects the intruder passing through the security perimeter, the control unit comprising;

a detector for determining the presence of a significant reflecting body based on the target echo;

a sonar sensor module for processing data of the reflecting body; and

,

a processor for determining at least one estimator based on the target echo and for determining a target path based on the at least one estimator.

32. The system of claim 31 wherein the data of the reflecting body comprises one of tracking data, size of the target and amplitude data.

33. The system of claim 31 wherein the at least one estimator comprises an estimate of a parameter associated with the target.

34. The system of claim 31 wherein the at least one estimator comprises an estimate of a parameter associated with a path of the target.

35. The system of claim 34 wherein the parameter is associated with one of path consistency, closest point of approach, depth, speed, and size.

36. The system of claim 31 wherein determining a target path based on the at least one estimator comprises matched-field tracking.

37. The system of claim 36 wherein the matched-field tracking includes searching a collection of simulated tracking data and matching the simulated tracking data to actual sonar data.

38. The system of claim 37 further comprising an adjuster for adjusting the estimated target path to minimize an error measure between corresponding tracking data and actual tracking data.

39. The system of claim 31 wherein the processor further determines a threat level estimate of the target.

40. The system of claim 39 wherein determining the threat level estimate comprises obtaining a criterion corresponding to the target and comparing the criteria with a potential threat characteristic.

41. The system of claim 40 wherein the criterion comprises a target level threat score including one of a course direction threat score, an amplitude of a received sonar signal from the target, a target echo width, and a target size.

42. The system of claim 41 further comprising an alarm capable of initiating a unique alarm at any one of a plurality of levels, each level of the plurality of levels associated with a predetermined threat level.