Patent Publication Number: US-7911336-B1

Title: Container monitoring system

Description:
This is application claims the priority, as a continuation in part, of application Ser. No. 11/705,142, filed on Feb. 9, 2007 (to be issued on Feb. 23, 2010, as U.S. Pat. No. 7,667,593), and claims the priority of application Ser. No. 10/998,324, filed on Nov. 29, 2004 (now U.S. Pat. No. 7,176,793), from which the Ser. No. 11/705,142 application claims priority. The disclosures of both of these applications are incorporated herein by reference in their entireties. 
    
    
     BACKGROUND 
     The present exemplary embodiment relates to the detection arts. It finds particular application in conjunction with cargo containers which are used to ship products, foodstuffs, and other materials from one country to another, and will be described with particular reference thereto. However, it is to be appreciated that the present exemplary embodiment is also amenable to other like applications. 
     Cargo containers are widely used for shipping materials by land or by water from one country to another. Knowing the contents of such containers has become of increasing importance in detecting potential threats. It has thus become extremely important to monitor the contents of such containers for harmful materials, such as explosives, harmful biological material, and radiation materials. 
     U.S. Pat. No. 7,176,793 discloses a detection device in the form of a strip for use in an enclosed container. The detection strip includes nanosensors for detecting materials that are harmful to human beings within an enclosed container and for transmitting a corresponding resonance frequency. One or more detection strips are initially placed within a container, depending on the size of the container. The detection devices are designed to send off specific resonant frequency signals which are correlated to any harmful material detected within the container. A serial number computer chip is provided for specifically identifying the detection device and transmitting a corresponding resonance frequency, which allows the container to be identified. A power source is provided for operating the detection strip. A hand held or stationary monitor is provided for monitoring the container for any signals given off from the detection strips within the container. The detection devices are designed to give off a predetermined amount of background signal. In consequence, if no such signals are received, the container is highly suspect as being tampered with, allowing such a container to be quickly removed and its contents examined. 
     For some applications, hazardous materials may be at relatively low concentrations, for example hazardous nuclear materials may be distributed in amongst other materials or chemical or biological warfare agents may be in small concentrations within the container. As a consequence, the detection device may give off an intermittent or no signal. One solution is to enlarge the size of the detection strip. However, very large detection strips may be unwieldy and difficult to attach to the container. 
     The exemplary embodiment provides a solution to this problem by incorporating the nanosensors in a coating which is applied to one or more interior walls of the container. The nanosensors are extremely small detectors, of micro, meso, or nano size. The signals output by the nanosensors can be received by one or more detection strips which communicate the signals to the exterior monitor. 
     BRIEF DESCRIPTION 
     In accordance with one aspect of the exemplary embodiment, a detection system for an enclosed container includes many nanosensors for detecting materials harmful to human beings, within an enclosed container and transmitting a corresponding resonance frequency and at least one detection device which detects a condition of the nanosensors and outputs a signal responsive thereto. 
     In another aspect, in combination, a cargo container in which any suitable cargo is placed for transport from one place to another place, a detection system disposed in the container for detecting tampering with the container, the detection system including numerous nanosensors which are designed to transmit a predetermined frequency, means of storing and transmitting information about the condition of the nanosensors and optionally a serial number specific to the detection system using an ESN computer chip, and a power source for operating the detection system. 
     In another aspect, a method for detecting harmful materials including embedding nanosensors in walls of an enclosed container or in a coating applied to the container walls and monitoring signals output by the nanosensors with a monitoring device external to the container. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a shipping container and monitoring system in accordance with one aspect of the exemplary embodiment; 
         FIG. 2  is a cross-sectional view of the shipping container of  FIG. 1 ; and 
         FIG. 3  is a top view of one embodiment of a detection device mounted on an interior wall of the container of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     With reference to  FIG. 1 , there is shown a container  10  which can be of any size, including large cargo containers. Cargo containers  10  are generally made of metal and include eight walls, namely, a bottom  12  with a pair of opposing, upstanding similar sides  14 , a pair of similar opposing ends  16 , and a top  18 , for covering and closing the cargo container  10 . The walls  12 ,  14 ,  16 ,  18  may be made of metal, such as steel or alumina, or form non-metallic material, such as carbon fiber, or a combination thereof. 
     As illustrated in  FIG. 2 , the walls  12 ,  14 ,  16 ,  18  define an interior space  20  for receiving a cargo  22 , such as a liquid, solid or other material. Each wall has an interior surface  24 , some or all of which may be in contact with the cargo  22 . Extremely small detectors, of micro, meso, or nano size, which are referred to herein as nanosensors  26 , are carried by the interior surfaces  24  of walls of the container. The nanosensors may detect harmful materials, such as explosives, radioactive materials, harmful chemicals, such as chemical warfare agents, nerve gases, biological materials, such as such as gases, anthrax and other germ warfare agents, narcotics and other illegal drugs, or combinations thereof. In some cases, nanosensors may be configured for detection of heat in the container wall, e.g., a temperature above those normally experienced by the container  10  which is indicative of tampering, e.g., from the heat applied by a blow torch. In other embodiment, the nanosensors are capable of detecting small changes in heat resulting from the presence of humans or animals in the container. 
     In one embodiment, one or more of the walls&#39; interior surfaces  24  is at least partially covered with a coating  28 , such as a paint, in which many thousands, millions, or billions of nanosensors  26 , are embedded. The coating  28  is one which is free of any of the harmful materials which are to be detected by the nanosensors. By free it is meant that any harmful materials are at too low a concentration for the nanosensors to detect. The nanosensors may be embedded in a surface of the coating, for example, by spray painting the coating on the container walls and, before the coating is set, spraying the nanosensors on to the surface such that the detectors are exposed to the cargo. 
     In another embodiment, the nanosensors are embedded in an interior layer of the container wall, such as in a carbon fiber wall or layer of the container, such that they are exposed to the cargo. 
     The nanosensors combine to detect many different harmful materials, such as explosives, radioactive materials, harmful chemicals, and biological gases, germs, illegal drugs, or combinations thereof, and the like. In particular, the nanosensors  26  produce and transmit resonant frequencies corresponding to the harmful materials detected. Depending on the materials to be detected, different nanosensors  26  may be used, singly or in combination. For example, the nanosensors may be in the form of particles comprising a substrate such as carbon (e.g., carbon nanotubes) to which is bound a receptor molecule that is specific for a particular harmful substance (or class of harmful substances) or responsive to a change in physical conditions, such as responsive to heat. 
     Depending on the size of the container  10 , one or more detection devices  30  are placed within the container  10 . In the exemplary embodiment, the detection devices are located proximate the nanosensors, e.g., fixed to an interior surface of a wall on top of the coating or within it. The exemplary detection devices are capable of withstanding extremes of temperatures, humidity, vibrations, and salt air. Resonant frequencies emitted by the nanosensors  26  are carried through the coating or container wall to the detection device  30 . The transfer of resonant frequencies may be aided by wires positioned in the coating  28  or on the container wall or by having multiple collectors, serving as repeater stations, disposed around the container walls which forward the resonant frequencies, e.g., amplified, to the detection device  30 . The nanosensors can be configured to set off adjacent like sensors so that a very large volume of a particular type of nanosensor(s) change their resonant frequency. This chain-like reaction thus helps to detect the very small voltage change over a distance. 
     The detection device  30 , as best seen in  FIG. 3 , comprises a flexible strip  32 , which may be composed of any suitable plastic material. The detection device  30  includes a sensor chip  34  or other means for measuring the resonant frequency. The sensor  34  may be embedded in or otherwise supported by the strip  32 . The sensor chip  34  detects the resonant frequencies transmitted by the nanosensors or intermediate collectors, e.g., as a small change in voltage, and generates a signal responsive thereto, such as a voltage signal or simply an amplification of the resonant frequency. One specific signal may be reserved for chemical warfare agents, another for radioactive materials, and so forth. Or, each particular harmful material may have its own specific signal. A transmitter chip  36 , such as an LDA (local data adapter/collector), capable of multiplexing data transmitted by the encrypted serialized chip is supported on the strip. In one embodiment, the LDA  36  is capable of data transmission by satellite uplink and/or by direct line of sight up to 15-30 miles. U.S. Pat. No. 7,292,828, the disclosure of which is incorporated herein by reference, discloses one multichannel transmitter which employs wireless telemetry to send signals indicative of harmful materials to a remote receiver that may be used herein. Sensor chip  34  and LDA  36  may be separate or combined into a single chip. 
     In addition to the nanosensors which emit resonant frequencies in response to detection of harmful materials, a separate and distinct calibrated general background resonant frequency may be emitted by a specific group of the nanosensors  26 . These nanosensors  36  may be embedded in the coating or container wall together with the nanosensors  26  and/or are embedded in the strip  32 . 
     A global positioning system (GPS) computer chip  40  may be embedded in the detection strip  32  for providing a signal representative of the location of the strip and its associated container. For containers  10  which are below deck and/or covered by many other containers, the chip  40  may receive a signal from a corresponding GPS chip in a local container if the satellite signal is too weak to be picked up. An encrypted serial numbered (ESN) computer chip  4  may also be embedded in or otherwise supported by the strip  32 . The ESN chip  44  generates a signal corresponding to the device&#39;s unique serial number which may also be transmitted via the LDA. The components of the detection device  30 , such as the sensor chip, LDA chip, and GPS chip may all be powered by a single power source or by separate power sources, such as a battery. For example, a low voltage motion activated power source  46  is carried by the strip. The power source  46  may be disconnected from the components by a magnetic switch  48  which completes the circuit with the components  34 ,  36 ,  40 ,  44  only intermittently. The container  10 , when moved, may activate the power source  46  to maintain operation of the detection device  30 . In this way, the power source is not drained two quickly. A battery thus may last for about two years before it needs to be replaced. 
     The exemplary GPS chip  40  stores not only the origin of a particular container  10 , but tracks the route which the container  10  travels from the origin to its destination which, for our purposes, is the United States. This information can be readily accessed from the GPS chip  40 . The ESN chip  44  stores an encrypted serial number that is specific to the one or more particular detection devices  30 , which are assigned to the container  10  involved. The ESN chip  44  produces and transmits a distinct resonant frequency which can be accessed and used to track down the owner of the detection devices  30  within the container  10 , since a log of the owner of every detection device  30  is maintained. The strip may be equipped with anti tamper logic, e.g., in the LDA chip  44 . 
     As illustrated in  FIG. 1 , an external monitoring system may include any suitable hand-held or stationary monitoring device  50 . This is used to monitor the resonant frequencies produced/signals generated and transmitted by the nanosensors  26  via the detection device  30  and the GPS and ESN computer chips  40 ,  44  to reveal the contents of a container  10 , whether the contents be hazardous or not. The monitoring device  50  is able to detect a separate and distinct calibrated general background resonant frequency from some of the numerous nanosensors  26 , embedded in the coating  28  or detection strip  32  as a means to ensure that the detection strip  32  is functioning. If not, the container  10  is considered suspect and removed to a remote location for further examination and review or, in some cases, the suspect container  10  may be rejected and sent back to its place of origin. The monitoring device  50  may designed to translate the resonate frequencies received into digital readouts on a screen  52  of the monitoring device  50 , and provide printouts at a remotely located printer, if desired. In one embodiment, the monitoring system includes a computer logging system  54  which receives the signals from the devices  30  in the containers  10  and uploads them periodically to a corresponding review system computer  56  remotely located, e.g., located on shore, e.g., in the port of entry, or at a customs post. The signals from the logging system  54  may be transmitted via a satellite link  58 . In this way, either or board ship or in port, a reviewer can track the activity in each of the hundreds or thousands of containers on board a container ship wishing to enter port determine if any of the containers pose a threat, and either refuse entry of the container ship to port or provide for an inspection of the container at sea or when it reaches port. For vehicles arriving by land, the reviewer can track the contents of the containers before they reach a customs post or weigh station and prevent the vehicle from crossing the border if appropriate. 
     The detection strips  32  may each have a sticky side which can firmly adhere to sides of the container  10 , e.g., to the surface of the coating  28  or to a coating-free area of the container wall. When not in use, the sticky side of the detection strip  32  is covered by a protective strip which can be peeled away when the strip  32  is ready to be applied to the container  10 . The sticky side of each detection strip  32  may be provided with one or a number of metal studs or strips  60  for contact with the metal, carbon fiber, or painted interior surfaces of a container  10  to facilitate or improve the transmission of the resonant frequencies from the detection devices  30  to a monitoring device  50  outside the container  10 . For example, a single, continuous metal strip or stud  60  may be placed longitudinally of the detection strip  32  between the opposing marginal edges of the detection strip  32 , or a number of similar, short metal studs  60  may be spaced longitudinally of the detection strip  32  in transversely oriented relation on the detention strip  32  as shown in  FIG. 3 . 
     As will be appreciated, while the exemplary components  34 ,  36 ,  40 ,  44  and power source  46  are conveniently located on a single strip, in other embodiments, some of the components, such as the GPS system, may be located on a separate strip or otherwise mounted to the container wall. 
     Thus, there has been described a unique detection system comprising a detection device  30  and nanosensors  26  that are placed within an enclosed space  20  of a container  10  to detect any solids, liquids, or gases which may prove to be harmful to human beings. For example three separate detection devices  30 , disposed against the top and adjacent two sides, midway between the opposing ends of the container  10 , may be sufficient to detect signals from the nanosensors  26  corresponding to harmful materials in a standard size cargo container  10 . Each detection device  30  may have its own distinct ESN computer chip  44 . Otherwise, there would be no way to tell if one of the ESN computer chips  44  was destroyed or removed from the container  10 , if all three ESN computer chips  44  were identical and transmitted the same resonant frequency. 
     The exemplary embodiment has been described with reference to the preferred embodiments. Obviously, modifications and alterations will occur to others upon reading and understanding the preceding detailed description. It is intended that the exemplary embodiment be construed as including all such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.