WO2006052776A2

WO2006052776A2 - Vehicle denial security system

Info

Publication number: WO2006052776A2
Application number: PCT/US2005/040079
Authority: WO
Inventors: Douglas E. Piper; Thomas E. Browning; Mary Hester Owens
Original assignee: Woven Electronics Corporation, A South Carolina Corporation
Priority date: 2004-11-09
Filing date: 2005-11-04
Publication date: 2006-05-18
Also published as: WO2006052776A3

Abstract

A vehicle barricade includes an optical time domain reflectometer (OTDR 18) connected to fiber optic sensor (within 10) embedded within a cable (10) of the barricade. The barricade is capable of detecting the location of intrusion a vehicle and alerting the appropriat person.

Description

VEHICLE DENIAL SECURITY SYSTEM

BACKGROUND OF THE INVENTION

This invention relates to a vehicle denial security system for denying entry of a vehicle into a secured area and/or detecting an attempt of a vehicle to penetrate a perimeter of the secured area. With the increase in terrorism in the United States and the rest of the world, the need for an effective security system to detect and/or prevent a vehicle break in a barrier surrounding and protecting a secured area is a problem to which considerable attention needs to be given.

SUMMARY OF THE INVENTION A vehicle denial security system is provided for detecting a fault condition at one or more predetermined locations in a perimeter surrounding a secured area representing an attempt to penetrate the perimeter. The system includes a barricade component surrounding the secured area to define a prescribed perimeter for protecting the secured area. A sensor barricade cable is included in the barricade component which must be severed in order to penetrate the prescribed perimeter and secured area. The barricade cable has sufficient strength to deny penetration by an ordinary automobile and truck vehicle. An optical fiber sensor line embedded in said barricade cable for detecting the fault condition. A processor in connected in communication with the fiber sensor line for generating a fault signal in response to the occurrence of a fault condition which includes the location of the fault condition. A communication output

Page i of 17 operatively associated with the processor for communicates the fault signal so that a proper response can be made to said fault condition.

DESCRIPTION OF THE DRAWINGS

The construction designed to carry out the invention will hereinafter be described, together with other features thereof. The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawings forming a part thereof, wherein an example of the invention is shown and wherein:

Figure 1 is a schematic diagram illustrating one embodiment of a vehicle denial security system according to the invention; Figure 2 is a schematic diagram illustrating a computerized security interface component for a vehicle denial security system according to the invention;

Figure 3 is a perspective view of a barricade cable having an embodied senor line extending through the cable which may be incorporated into a barricade component of a vehicle denial security system according to the invention;

Figure 4 is an illustration of one embodiment of a physical form of a vehicle denial security system wherein the barricade component includes a plurality of barricade cables is incorporated into a conventional fence structure; Figure 5 is a schematic diagram of another embodiment of a vehicle denial security system according to the invention having three barricade cables incorporated into a barricade component of the invention;

Figure 6 is a graphic display of the OTDR signal when the vehicle denial security is in a normal, undisturbed condition; and Figure 7 is a graphic display of the OTDR signal when a fault condition has occurred in the barricade component of the security system, and a characteristic fault signal is produced.

Figures 8-9 are flow charts for a security interface system for detecting a fault in the barricade security component and producing a characteristic signal indicating the location of the fault.

DESCRIPTION OF A PREFERRED EMBODIMENT The present invention is now described more fully herein with reference to the drawings in which the preferred embodiment of the invention is shown. This invention may, however, embody other forms and should not be construed as limited to the embodiment set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the scope of the invention to those skilled in the art.

The detailed description of some of the components that follow may be presented in terms of steps of methods or in program procedures executed on a computer or network of computers. These procedural descriptions are representations used by those skilled in the art to most effectively convey the substance of their work to others skilled in the art. These procedures herein described are generally a self-consistent sequence of steps leading to a desired result. These steps require physical manipulations of physical quantities such as electrical or optical signals capable of being stored, transferred, combined, compared, or otherwise manipulated. A computer readable medium can be included that is designed to perform a specific task or tasks. Actual computer or executable code or computer readable code may not be contained within one file or one storage medium but may span several computers or storage mediums. The terms "computer," "processor," and "server" may be hardware, software, or combination of hardware and software that provides the functionality described herein, and may be used interchangeably.

Certain aspects of the present invention are described with reference to flowchart illustrations of methods, apparatus ("systems"), or computer program products according to the invention. It will be understood that each block of a flowchart illustration may be implemented by a set of computer readable instructions or code. These computer readable instructions may be loaded onto a general purpose computer, special purpose computer, or other programmable data processor or processing apparatus to produce a machine such that the instructions will execute on a computer or other data processing apparatus to create a means for implementing the functions specified in the flowchart block or blocks. Accordingly, elements of the flowchart support combinations of means for performing the special functions, combination of steps for performing the specified functions and program instruction means for performing the specified functions. It will be understood that each block of the flowchart illustrations can be implemented by special purpose hardware based computer systems that perform the specified functions, or steps, or combinations of special purpose hardware or computer instructions. Referring now to the drawings, the invention will now be described in more detail. As can best be seen in Figure 1 , a vehicle denial security system, designated generally as A, is illustrated. The security system includes a barricade cable component, designated generally as B, and a security interface component, designated generally as C. Barricade component B prevents penetration of a vehicle such as an automobile or truck, and generates a fault signal if attempt is made to compromise the barricade surrounding a secured area 14. Advantageously the barricade component includes a braided barricade cable 10 establishing a vehicle denial perimeter 12 of a secured area 14. The barricade cable has sufficient flexibility be routed to enclose a desired perimeter of secured area 14, and also deny penetration into the secured area by a vehicle attempting to creash through the barricade. According to the invention, it has been discovered, quite unexpectedly, that an aerial telecommunications cable manufactured by Alcoa, Inc., under the brand name HexaCore OPT-GW, may be advantageously utilized as a barricade cable in a vehicle denial security system. The cable is made from aluminum cad strands twisted together and is used as a ground line in telephone transmission towers. The cable includes a fiber optic transmission line extending through a hollow tube embedded in the structure which is leased for telecommunication services in the utility industry. Typically, the Alcoa cable is used as a ground line in a three line telecommunications transmission tower.

It has been found that the strand cable is strong enough to prevent breakage by a vehicle and that the communication line may be modified to provide a sensor line. Cables of this type have a rated breaking strength of about 15,000 to 60,000 psi and a modulus of elasticity of about 22,000 kps. The cable strength may be selected based on the security application being made. The cable is flexible enough so that the cable may be configured to provide a perimeter barrier about a prescribed secured area.

As mentioned above, braided cable 10 is provided with at least one sensor line 16 extending through the center of the cable (Figure 3). Sensor line 16 is advantageously a fiber optic sensor line, and is connected at one end to an optical time domain reflectometer (OTDR) 18. An OTDR is routinely utilized to monitor maintenance of fiber optic telecommunication network systems. Typically, the OTDR is used to sense a fiber breakage, water seepage, irregular bends, or other defects in one or more optical fibers of a communication network. For example, in large municipalities it is not uncommon for there to be 1 ,000 miles of communication fibers in an optical fiber network. As illustrated in Figure 1 , an explementary embodiment shows a rectangular perimeter established with four corners 12a, 12b, 12c, and 12d. The perimeter originates at 10a of barricade cable 10 connected in communication with OTDR 18 and terminates at a terminal end of the barricade cable at a terminal box 20. The terminal end of the braided cable need not be physically or electrically connected to the OTDR.

OTDR 18 is connected in communication with security interface component C. As can best be seen in Figure 2, the security interface component includes a computer 26 having a computer program 28 containing a set of operating instructions embodied in a computer readable code residing in a memory 30 of the computer. The computer is connected to a display 32 or other communicating device for communicating the occurrence of a fault signal 42 to an operator of the system. Figure 5 illustrates another embodiment of the invention wherein three barricade components B are provided in a vehicle denial security system according to the invention wherein each barricade component is connected to the interface security system C by means of an internet 32 or other network system. Referring now to Figures 3 and 4, braided barricade cable 10 is illustrated as containing a hollow core tube 36 carried radially inward of the cable through which sensor wire 16 extends. The braided cable may be incorporated into many forms of a barricade. For example, Figure 4 shows a three rail fence which may be used to establish perimeter 12 of the secured area. Braided cable 10 may be routed through the middle rail of the fence so that any vehicle that attempts to crash through the fence will be detected. Not only is the barricade cable strong enough to prevent the vehicle from crashing, in the event the line is severed, or the vehicle does break through the line, fault signal 40 will be generated. If desired, more than one barricade cable may be incorporated into the fence. For example, a barricade cable may be routed through each of the rails in the fence, and the resulting security system is illustrated at Figure 5. Braided cable 10 can be arranged in other forms as well. For example, the braided cable may be arranged as a barricade in front of a hydroelectric or other dam to prevent entrance of a water craft, or protect the front side of the dam and the like. Various means and forms of mounting the barricade cable to deny entrance of a vehicle or other intrusion can be had according to the invention. As used herein, "fault condition" means a condition in which braided cable

10 has been cut or broken through by a vehicle, and/or encountered material damage, as distinguished from accidental damage. OTDR 18 continuously scans the optical sensor line within the braided cable, from one end to the other around perimeter 12, and communicates scan signals 40 in the line to security interface component C, as will be explained more fully below. Computer 26 is programmed to compare the scan signals to a baseline signal D to determine whether predetermined signal deviation representing a fault condition has occurred. In the event the fault condition is detected, fault signal 42 is generated by the interface component along with a computation of the type of fault and location of the fault condition around perimeter 12 of the barricade. For example, display 32 may include a map of the barricade perimeter depicting the location of the fault condition on the map.

Conventional input devices, such as a keyboard or mouse, may be provided for operating computer 26. Other means of displaying the OTDR signal may also be used. Computer 26 continuously monitors a scan signal 40 produced by the

OTDR when scanning the fiber optic cable. When the computer is first turned on, the computer acquires baseline signal D from the OTDR, as can best be seen in Figure 5.. The baseline represents the status of the fiber optic cable being monitored at a normal, undisturbed state. For example, while initially scanning the line the scan signal will likely include some noise attenuations at 44, followed by a launch signal 46 in the scan. A launch is created by a significant attenuation or spike in the scan to a normalized level. The normalized level at 48 is the beginning of baseline signal D. The system continues to read the baseline until a drop occurs at 50. The drop indicates the end of sensor line 12 being scanned. After the drop, noise 44 again will be recorded by the OTDR. The computer system will then ignoresmall peaks 52a and 52b at the beginning and at the end of the baseline signal which is merely reflections of the launch and the drop. Baseline signal D established for the security application being made will be compared to all future scans of the fiber optic line to determine if a fault condition has occurred. During scanning, computer 26 continuously receives scan signals 40 representing scans of the fiber optic cable from the OTDR. A cable being monitored will have a characteristic baseline signal depending on the security application being made and security configuration. A straight cable extending perfectly vertical from the OTDR will be one of the few instances that no attenuations will be found in the baseline. Fiber optic barricade cable 10 having a rectangular shape, as illustrated in Figure 1 , will likely have four distinct attenuations at 12a, 12b, 12c, and 12d. Each attenuation represents one of the corners in the rectangular shape of the cable. With each repetitive scan, the computer system compares the scan signal to the baseline signal to see if any signal deviations are detected. If a signal deviation is detected, the computer analyzes the deviation signal to determine what type of fault has occurred, as well as the location of the fault along perimeter 12. If the scan attenuation matches a baseline attenuation, such as at 12a-12d, the computer system will not recognize a fault condition. Thus, every attenuation detected by the computer system will not indicate a fault and may simply indicate a pre-existing bend attenuation. Further, some signal attenuations will be slight, indicating a slight movement of the cable that does not indicate a fault. The signal deviations that most concern a user of this system will be those that show a significant fault. The location of the attenuation on the signal will correspond to a location on the fiber optic cable where a fault may have occurred. As can best be seen in Figure 7, in the event that a fault condition 50 is created in braided barricade cable 10, fault signal 42 occurs in scan signal 40. Computer analysis involving a comparison of baseline signal D and fault condition signal 42 indicates an abrupt deviation in attenuation sufficient to create a fault signal. Computer 26 generates a fault signal which is delivered to display 32 in the form of a map or other information indicating the location of the fault condition which may be looked up in a computerized table. For example, an attenuation of -62DB may represent a complete break in the optical fiber sensor line 12 and hence barricade cable. This information may be stored in a table format allowing for quick retrieval by computer readable instructions. A fault condition distance of 2,100 meters may be the location of an entrance gate to the secured area according to the location lookup table. A computer generated map may be quickly displayed at 32. Various ways of responding to the fault condition may be had at that time. For example, law enforcement personnel may be dispatched immediately to the location, various alarms may be activated, and other means of communicating the fault condition in a manner dictated by the security application being made.

Computer program 28 includes instructions for communicating with OTDR 18 and receiving repetitive scan signals, and analyses instructions for comparing the scan signals to the baseline signal which has been established. The instructions include lookup instructions for looking up the location of a fault signal in the event the analysis instructions determine a deviation from the baseline signal. The lookup instructions look to see if the deviation matches the level of deviation required to indicate a complete break of the barricade cable, material damage to the cable, and/or other conditions in the cable which amount to a fault condition. The computer program may also include a map of the secured area and instructions to look up the location of the fault condition in response to the distance measured by the OTDR. Display instructions may include instructions for displaying the map and the location on display 32. Alarm instructions can be used to alert the attendant to the map display and the fault signal generally.

Referring now to Figures 8 and 9, flowcharts detailing the computerized operation of the security system are shown. Figure 8 shows the initialization process of determining baseline D from scan signal 40 associated with barricade cable 10 in the security system. At step 60, the system initially scans fiber optic sensor line 12, extending through barricade cable 10. At step 62, the system error checks the information coming from the fiber optic barricade cable. For example, a user may input parameters indicating the length of the cable to be scanned. If the length scanned by the system is greater or less than this parameter length, then the system will return an error and rescan the line from the start to ensure a proper base line is detected. Other parameters such as attenuations that should be found in the line may also be entered to assist in error checking. If a launch signal 46 is detected at step 64, the system will begin acquiring and storing baseline signal D in computer memory 30 at step 46. If the attenuation is not considered a launch signal, the system will continue to scan fiber optic line 12 until it detects a launch attenuation. The launch signal occurs when a significant rise from the noise floor occurs in the reading of the signal from the OTDR. Any insignificant attenuations simply indicate noise 44 and do not show the beginning or the end of the baseline signal.

Once the system has acquired a launch and begun measuring the baseline at step 66, it will continue to do until it detects a drop signal 50 at step 68. The drop signal is the inverse of the launch signal indicating the end of the baseline signal. The drop signal returns the scan signal of the fiber optic line to noise 44. At this point, the system will end acquiring the baseline at step 70. At step 72 the computer analysis adjusts the baseline signal for reflection. There is a distance immediately following the launch and immediately preceding the drop that is not a measurement of the baseline but rather a reflection signal at 52a and 52b occurring at the beginning and end of the line. This reflection is not be considered part of baseline signal D, therefore, it is removed from the baseline signal at step 72. At step 74, the actual baseline is stored by the system in computer memory for comparison to future scan signals. The baseline is necessary in order to make all comparisons to future scans to determine a fault condition is occurring in the braided security cable of the barricade component.

Figure 9 shows an overview of the normal operation of the security system while scanning the sensor line. After establishing the baseline signal, the scanning of the line will take place at step 78. The system will determine if any attenuation deviation from the baseline is detected at step 80 while scanning the sensor line. If no deviation from the baseline has taken place, the system will return to step 78 and continue to scan the line for an attenuation deviation. Attenuation deviations do not necessarily have to indicate a fault. Sometimes attenuations will indicate the crimping or some other bend in the barricade cable. If these existed at the time of the determination of the baseline, then no action is taken if the attenuation found matches this baseline attenuation. If the attenuation does not match the attenuations in the baseline signal, the system will look up the deviation level and determine if a fault signal condition exists. If so, the computer will generate a fault signal at 86. The fault signal can comprise multiple indicators. For example, an audible indication may be given to the user of the system indicating a fault. In a further embodiment, a visual indication may be given to the user indicating the location of the fault. In a further embodiment, the visual display may comprise a map with an indication at the point on the map where the fault has taken place.

While a preferred embodiment of the invention has been described using specific terms, such description is for illustrative purposes only, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims.

Claims

What is claimed is:

1. A vehicle denial security system for detecting a fault condition at one or more predetermined locations in a perimeter surrounding a secured area representing an attempt to penetrate the perimeter comprising: a barricade component surrounding the secured area to define a prescribed perimeter for protecting the secured area; a sensor barricade cable included in said component which must be severed in order to penetrate said prescribed perimeter and said secured area; said barricade cable having sufficient strength to deny penetration of said cable by an ordinary passenger driven vehicle; an optical fiber sensor line embedded in said barricade cable for detecting the fault condition; a processor in communication with said fiber sensor line for generating a fault signal in response to the occurrence of a fault condition and determining the location of said fault condition; and a communication output operatively associated with said processor for communicating said fault signal so that a proper response can be made to said fault condition.

2. The system of claim 1 wherein each said fault condition includes said barricade cable being severed.

3. The system of claim 2 wherein said processor includes means for receiving signals from said sensor line and generating said fault signal in response to a predetermined deviation in said signal.

4. The system of claim 1 wherein said fault condition includes said cable being materially damaged by impact to an extent that an intention to break through said barricade cable is recognized.

5 The system of claim 4 wherein each said fault condition includes said barricade cable being severed.

6 The system of claim 1 including optical time domain reflectometer (OTDR) operatively connected to said optical sensor line for scanning said sensor line and generating scan signals for delivery to said processor.

7. The system of claim 6 including an optical time domain reflectometer (OTDR) operating a sensor signal; said processor including a set of computer readable instructions stored in a memory of said processor; said instructions including instructions for continuously receiving scan signals from said fiber optic sensor line, comparing said base line signal to said scan signal, generating a fault signal in the event said comparison indicates

/ a fault condition, and activating said communication component in response to said fault signal being generated so that personnel are alerted to said fault condition and the location thereof.

8 A method of denying penetration of a vehicle into a secured area comprising: providing a barricade sensor cable around a defined perimeter of the secured area having sufficient strength to prevent penetration by said vehicle wherein said cable includes a fiber optic sensor line; generating a scan signal in said sensor line; processing said scan signal to establish a base line signal from said sensor line in response to said cable being in a normal condition; comparing said baseline signal to said scan signals, and generating a fault signal in response to receiving a scan signal having a predetermined deviation from said base line signal; and processing said deviation signal to establish a type and location of a fault occurring in said barricade and perimeter; and alerting personnel of said fault and location.

9. The method of claim 8 including displaying a map of the secured area showing said fault to alert personnel that said fault condition has occurred.

10. The method of claim 8 including generating said scan signal using g an optical time domain reflectometer (OTDR).