# Patent

## Title
System for monitoring containers to maintain the security thereof

## Abstract

A container and contents monitoring system includes a device, a reader, a server, and a software backbone. The device communicates with the reader in order to determine the security of the container to which the device is attached. The reader transmits the information from the device to the server. The sensor senses a distance or an angle value between a door of the container and a frame of the container and the sensed value is then transmitted to the device. The device obtains a baseline value that is related to a calculated mean value. The device also obtains a detection threshold. The device determines if a security condition has occurred based on the sensed value and the detection threshold.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of prior U.S. patent application Ser. No. 11/087,794, filed Mar. 23, 2005, now U.S. Pat. No. 7,333,015, which claims the benefit of prior Provisional Patent Application No. 60/556,106 filed on Mar. 24, 2004, the disclosures of which are incorporated by reference. This application further incorporates by reference U.S. patent application Ser. No. 10/667,282, filed on Sep. 17, 2003.


BACKGROUND
1. Technical Field
The present invention relates to a method of and system for monitoring the security of a container and, more particularly, but not by way of limitation, to a method of and system for monitoring the security of intermodal freight containers throughout a supply chain to discourage or prevent such urgent problems as terrorism, and also illegal immigration, theft or adulteration of goods, and other irregularities.
2. History of the Related Art
The vast majority of goods shipped throughout the world are shipped via what are referred to as intermodal freight containers. As used herein, the term “containers” includes any container (whether with wheels attached or not) that is not transparent to radio frequency signals, including, but not limited to, intermodal freight containers. The most common intermodal freight containers are known as International Standards Organization (ISO) dry intermodal containers, meaning they meet certain specific dimensional, mechanical and other standards issued by the ISO to facilitate global trade by encouraging development and use of compatible standardized containers, handling equipment, ocean-going vessels, railroad equipment and over-the-road equipment throughout the world for all modes of surface transportation of goods. There are currently more than 12 million such containers in active circulation around the world as well as many more specialized containers such as refrigerated containers that carry perishable commodities. The United States alone receives approximately six million loaded containers per year, or approximately 17,000 per day, representing nearly half of the total value of all goods received each year.
Since approximately 90% of all goods shipped internationally are moved in containers, container transport has become the backbone of the world economy.
The sheer volume of containers transported worldwide renders individual physical inspection impracticable, and only approximately 2% to 3% of containers entering the United States are actually physically inspected. Risk of introduction of a terrorist biological, radiological or explosive device via a freight container is high, and the consequences to the international economy of such an event could be catastrophic, given the importance of containers in world commerce.
Even if sufficient resources were devoted in an effort to conduct physical inspections of all containers, such an undertaking would result in serious economic consequences. The time delay alone could, for example, cause the shut down of factories and undesirable and expensive delays in shipments of goods to customers.
Current container designs fail to provide adequate mechanisms for establishing and monitoring the security of the containers or their contents. A typical container includes one or more door hasp mechanisms that allow for the insertion of a plastic or metal indicative “seal” or bolt barrier conventional “seal” to secure the doors of the container. The door hasp mechanisms that are conventionally used are very easy to defeat, for example, by drilling an attachment bolt of the hasp out of a door to which the hasp is attached. The conventional seals themselves currently in use are also quite simple to defeat by use of a common cutting tool and replacement with a rather easily duplicated seal.
A more advanced solution proposed in recent time is an electronic seal (“e-seal”). These e-seals are equivalent to traditional door seals and are applied to the containers via the same, albeit weak, door hasp mechanism as an accessory to the container, but include an electronic device such as a radio or radio reflective device that can transmit the e-seal's serial number and a signal if the e-seal is cut or broken after it is installed. However, the e-seal is not able to communicate with the interior or contents of the container and does not transmit information related to the interior or contents of the container to another device.
The e-seals typically employ either low power radio transceivers or use radio frequency backscatter techniques to convey information from an e-seal tag to a reader installed at, for example, a terminal gate. Radio frequency backscatter involves use of a relatively expensive, narrow band high-power radio technology based on combined radar and radio-broadcast technology. Radio backscatter technologies require that a reader send a radio signal with relatively high transmitter power (i.e., 0.5-3 W) that is reflected or scattered back to the reader with modulated or encoded data from the e-seal.
In addition, e-seal applications currently use completely open, unencrypted and insecure air interfaces and protocols allowing for relatively easy hacking and counterfeiting of e-seals. Current e-seals also operate only on locally authorized frequency bands below 1 GHz, rendering them impractical to implement in global commerce involving intermodal containers since national radio regulations around the world currently do not allow their use in many countries.
Furthermore, the e-seals are not effective at monitoring security of the containers from the standpoint of alternative forms of intrusion or concern about the contents of a container, since a container may be breached or pose a hazard in a variety of ways since the only conventional means of accessing the inside of the container is through the doors of the container. For example, a biological agent could be implanted in the container through the container's standard air vents, or the side walls of the container could be cut through to provide access. Although conventional seals and the e-seals afford one form of security monitoring the door of the container, both are susceptible to damage. The conventional seal and e-seals typically merely hang on the door hasp of the container, where they are exposed to physical damage during container handling such as ship loading and unloading. Moreover, conventional seals and e-seals cannot monitor the contents of the container.
The utilization of multiple sensors for monitoring the interior of a container could be necessary to cover the myriad of possible problems and/or threatening conditions. For example, the container could be used to ship dangerous, radio-active materials, such as a bomb. In that scenario, a radiation sensor would be needed in order to detect the presence of such a serious threat. Unfortunately, terrorist menaces are not limited to a single category of threat. Both chemical and biological warfare have been used and pose serious threats to the public at large. For this reason, both types of detectors could be necessary, and in certain situations, radiation, gas and biological sensors could be deemed appropriate. One problem with the utilization of such sensors is, however, the transmission of such sensed data to the outside world when the sensors are placed in the interior of the container. Since standard intermodal containers are manufactured from steel that is opaque to radio signals, it is virtually impossible to have a reliable system for transmitting data from sensors placed entirely within such a container unless the data transmission is addressed. If data can be effectively transmitted from sensors disposed entirely within an intermodal container, conditions such as temperature, light, combustible gas, motion, radio activity, biological and other conditions and/or safety parameters can be monitored. Moreover, the integrity of the mounting of such sensors are critical and require a more sophisticated monitoring system than the aforementioned door hasp mechanisms that allow for the insertion of a plastic or metal indicative “seal” or bolt barrier conventional “seal” to secure the doors of the container.
In addition to the above, the monitoring of the integrity of containers via door movement can be relatively complex. Although the containers are constructed to be structurally sound and carry heavy loads, both within the individual containers as well as by virtue of containers stacked upon one another, each container is also designed to accommodate transverse loading to accommodate dynamic stresses and movement inherent in (especially) ocean transportation and which are typically encountered during shipment of the container. Current ISO standards for a typical container may allow movement on a vertical axis due to transversal loads by as much as 40 millimeters relative to one another. Therefore, security approaches based upon maintaining a tight interrelationship between the physical interface between two container doors are generally not practicable.
It would therefore be advantageous to provide a method of and system for: (i) monitoring the movement of the doors of a container relative to the container structure in a cost effective, always available, yet reliable fashion; (ii) providing for a data path for other security sensors placed in a container to detect alternative means of intrusion or presence of dangerous or illicit cargo to receivers in the outside world.
SUMMARY OF THE INVENTION
These and other drawbacks are overcome by embodiments of the present invention, which provides a method of and system for efficiently and reliably monitoring a container to maintain the security thereof. More particularly, one aspect of the invention includes a device for monitoring the condition of a container. The device includes a sensor for determining a distance or an angle value between a door of the container and a frame of the container. The device also includes a microprocessor that establishes a baseline value that is related to a calculated mean value from at least two detections. The microprocessor is also adapted to define a detection threshold and determine from the detection threshold and the distance or angle value whether a security breach has occurred.
In another aspect, the present invention relates to a device for determining whether a security breach of a container has occurred. The device includes a sensor for detecting at least one of a distance condition and an angle condition of the container and its contents. A microprocessor is also included for receiving the at least one distance condition and angle condition from the sensor. The microprocessor also establishes a range of acceptable condition values, such that the range of acceptable condition values are related to normal fluctuations in the sensed conditions of the container and its contents experienced during transport. A defined condition threshold and the sensed condition are also used by the microprocessor to determine the security condition of the container.
In another aspect, the present invention relates to a method of detecting a security breach of a container. The method includes the steps of placing a proximity sensor adjacent a structural member and a door of the container, the proximity sensor obtaining a sensed value, converting the sensed value to a distance value via a data unit located within the container, determining, by the data unit, whether a security breach of the door has occurred based on the distance value, communicating, by the data unit, a result of the determining step to an antenna interoperably connected to the data unit and located adjacent to and outside of the container, and transmitting, by the antenna, information relative to the communicating step.
In another aspect, the present invention relates to a method of detecting a security breach of a container. The method includes the steps of sensing a distance or an angle between a door of the container and a frame of the container and determining a baseline value being related to a calculated mean value from at least two detections. The method also includes defining a threshold value; and determining from the threshold value and the sensed value whether a security breach has occurred.



BRIEF DESCRIPTION OF DRAWINGS
A more complete understanding of exemplary embodiments of the present invention can be achieved by reference to the following Detailed Description of Exemplary Embodiments of the Invention when taken in conjunction with the accompanying Drawings, wherein:
FIG. 1A is a diagram illustrating communication among components of a system according to an embodiment of the present invention;
FIG. 1B is a diagram illustrating an exemplary supply chain;
FIG. 2A is a schematic diagram of a device according to an embodiment of the present invention;
FIG. 2B is a top view of a device according to an embodiment of the present invention;
FIG. 2C is a side view of a device according to an embodiment of the present invention;
FIG. 2D is a first perspective cut-away view of a device according to an embodiment of the present invention;
FIG. 2E is a second perspective cut-away view of a device according to an embodiment of the present invention;
FIG. 2F is a front view of a device according to an embodiment of the present invention;
FIG. 2G is a back view of a device according to an embodiment of the present invention;
FIG. 2H is a bottom view of a device according to an embodiment of the present invention;
FIG. 2I is a top view of a device according to an embodiment of the present invention;
FIG. 2J is a front view of the device of FIG. 2F as installed on a container;
FIG. 2K is a perspective view of the device of FIG. 2F as installed on a container;
FIG. 3A is a schematic diagram of a reader according to an embodiment of the present invention;
FIG. 3B is a diagram of a reader in accordance with the principles of the present invention;
FIG. 4 is a first application scenario of the system of FIG. 1A according to an embodiment of the present invention;
FIG. 5 is a second application scenario of the system of FIG. 1A according to an embodiment of the present invention;
FIG. 6 is a third application scenario of the system of FIG. 1A according to an embodiment of the present invention;
FIG. 7 is a fourth application scenario of the system of FIG. 1A according to an embodiment of the present invention;
FIG. 8 is a diagram illustrating a container-securing process in accordance with an embodiment of the present invention;
FIG. 9 is a diagram illustrating a container-security-check process in accordance with an embodiment of the present invention;
FIG. 10 is a flow diagram illustrating a door-sensor calibration process in accordance with an embodiment of the present invention;
FIG. 11 is a flow diagram illustrating a calculation of a range of alarm limits in accordance with an embodiment of the present invention; and
FIG. 12 is a flow diagram illustrating a tamper calculation in accordance with an embodiment of the present invention.



DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS OF THE PRESENT INVENTION
It has been found that a container security device of the type set forth, shown, and described below, may be positioned in and secured to a container for effective monitoring of the integrity and condition thereof and its contents. As will be defined in more detail below, a device in accordance with principles of the present invention is constructed for positioning within a pre-defined structural portion of the container which generally manifests minimal structural movement due to routine loading and handling and extending through a conventional interface between the container frame and door region therealong. An elastomeric gasket is conventionally placed around the door and extends through the interface region to ensure the container is watertight and the goods thus protected from weather. The device is adapted for: (a) easy tool-free installation; (b) self powered intermittent signal transmission; and (c) sensing of the pressure of the elastomeric door seal relative thereto for transmitting deviations thereof indicative of door movements of the container, including an intrusion therein.
FIG. 1A is a diagram illustrating communication among components of a system in accordance with principles of the present invention. The system includes a device 12, at least one variety of reader 16, a server 15, and a software backbone 17. The device 12 ensures that the container has not been breached after the container 10 has been secured. The container 10 is secured and tracked by a reader 16. Each reader 16 may include hardware or software for communicating with the server 15 such as a modem for transmitting data over GSM, CDMA, etc. or a cable for downloading data to a PC that transmits the data over the Internet to the server 15. Various conventional means for transmitting the data from the reader 16 to the server 15 may be implemented within the reader 16 or as a separate device. The reader 16 may be configured as a handheld reader 16(A), a mobile reader 16(B), or a fixed reader 16(C). The handheld reader 16(A) may be, for example, operated in conjunction with, for example, a mobile phone, a personal digital assistant, or a laptop computer. The mobile reader 16(B) is basically a fixed reader with a GPS interface, typically utilized in mobile installations (e.g., on trucks, trains, or ships using existing GPS, AIS or similar positioning systems) to secure, track, and determine the integrity of the container in a manner similar to that of the handheld reader 16(A). In fixed installations, such as, for example, those of a port or shipping yard, the fixed reader 16(C) is typically installed on a crane or gate. The reader 16 serves primarily as a relay station between the device 12 and the server 15.
The server 15 stores a record of security transaction details such as, for example, door events (e.g., security breaches, container security checks, securing the container, and disarming the container), location, as well as any additional desired peripheral sensor information (e.g., temperature, motion, radioactivity). The server 15, in conjunction with the software backbone 17, may be accessible to authorized parties in order to determine a last known location of the container 10, make integrity inquiries for any number of containers, or perform other administrative activities.
The device 12 communicates with the readers 16 via a short-range radio interface such as, for example, a radio interface utilizing direct-sequence spread-spectrum principles. The radio interface may use, for example, BLUETOOTH or any other short-range, low-power radio system that operates in the license-free Industrial, Scientific, and Medical (ISM) band, which operates around e.g. 2.4 GHz. Depending on the needs of a specific solution, related radio ranges are provided, such as, for example, a radio range of up to 100 m.
The readers 16 may communicate via a network 13, e.g. using TCP/IP, with the server 15 via any suitable technology such as, for example, Universal Mobile Telecommunications System (UMTS), Global System for Mobile Communications (GSM), Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Pacific Digital Cellular System (PDC), Wideband Local Area Network (WLAN), Local Area Network (LAN), Satellite Communications systems, Automatic Identification Systems (AIS), or Mobitex. The server 15 may communicate with the software backbone 17 via any suitable wired or wireless technology. The software backbone 17 is adapted to support real-time surveillance services such as, for example, tracking and securing of the container 10 via the server 15, the readers 16, and the device 12. The server 15 and/or the software backbone 17 are adapted to store information such as, for example, identification information, tracking information, door events, and other data transmitted by the device 12 and by any additional peripheral sensors interoperably connected to the device 12. The software backbone 17 also allows access for authorized parties to the stored information via a user interface that may be accessed via, for example, the Internet.
Referring now to FIG. 1B, there is shown a diagram illustrating a flow 2 of an exemplary supply chain from points (A) to (I). Referring first to point (A), a container 10 is filled with cargo by a shipper or the like. At point (B), the loaded container is shipped to a port of embarkation via highway or rail transportation. At point (C), the container is gated in at the port of loading such as a marine shipping yard.
At point (D), the container is loaded on a ship operated by a carrier. At point (E), the container is shipped by the carrier to a port of discharge. At point (F), the container is discharged from the ship. Following discharge at point (F), the container is loaded onto a truck and gated out of the port of discharge at point (G). At point (H), the container is shipped via land to a desired location in a similar fashion to point (B). At point (I), upon arrival at the desired location, the container is unloaded by a consignee.
As will be apparent to those having ordinary skill in the art, there are many times within the points of the flow 2 at which security of the container could be compromised without visual or other conventional detection. In addition, the condition of the contents of the container could be completely unknown to any of the parties involved in the flow 2 until point (H) when the contents of the container are unloaded.
FIG. 2A is a block diagram of the device 12. The device 12 includes an antenna 20, an RF/baseband unit 21, a microprocessor (MCU) 22, a memory 24, and a door sensor 29. The device 12 may also include an interface 28 for attachment of additional sensors to monitor various internal conditions of the container such as, for example, temperature, vibration, radioactivity, gas detection, and motion. The device 12 may also include an optional power source 26 (e.g., battery); however, other power arrangements that are detachable or remotely located may also be utilized by the device 12. When the power source 26 includes a battery (as shown herein), inclusion of the power source 26 in the device 12 may help to prolong battery life by subjecting the power source 26 to smaller temperature fluctuations by virtue of the power source 26 being inside the container 10. The presence of the power source 26 within the container 10 is advantageous in that the ability to tamper with or damage the power source 26 is decreased. The device 12 may also optionally include a connector for interfacing directly with the reader 16. For example, a connector may be located on an outer wall of the container 10 for access by the reader 16. The reader 16 may then connect via a cable or other direct interface to download information from the device 12.
The microprocessor 22 (equipped with an internal memory) discerns door events from the door sensor 29, including, for example, container-security requests, container-disarming requests, and container-security checks. The discerned door events also include security breaches that may compromise the contents of the container 10, such as opening of a door after the container 10 has been secured. The door events may be time-stamped and stored in the memory 24 for transmission to the reader 16. The door events may be transmitted immediately, periodically, or in response to an interrogation from the reader 16. The door sensor 29 shown herein is of the pressure sensitive variety, although it may be, for example, an alternative contact sensor, a proximity sensor, or any other suitable type of sensor detecting relative movement between two surfaces. The term pressure sensor as used herein thus includes, but is not limited to, these other sensor varieties.
The antenna 20 is provided for data exchange with the reader 16. In particular, various information, such as, for example, status and control data, may be exchanged. The microprocessor 22 may be programmed with a code that uniquely identifies the container 10. The code may be, for example, an International Standards Organization (ISO) container identification code. The microprocessor 22 may also store other logistic data, such as Bill-of-Lading (B/L), a mechanical seal number, a reader identification with a time-stamp, etc. A special log file may be generated, so that tracking history together with door events may be recovered. The code may also be transmitted from the device 12 to the reader 16 for identification purposes. The RF/baseband unit 21 upconverts microprocessor signals from baseband to RF for transmission to the reader 16.
The device 12 may, via the antenna 20, receive an integrity inquiry from the reader 16. In response to the integrity query, the microprocessor 22 may then access the memory to extract, for example, door events, temperature readings, security breaches, or other stored information in order to forward the extracted information to the reader 16. The reader 16 may also send a security or disarming request to the device 12. When the container 10 is secured by the reader 16, the MCU 22 of the device 12 may be programmed to emit an audible or visual alarm when the door sensor 29 detects a material change in pressure after the container is secured. The device 12 may also log the breach of security in the memory 24 for transmission to the reader 16. If the reader 16 sends a disarming request to the device 12, the microprocessor 22 may be programmed to disengage from logging door events or receiving signals from the door sensor 29 or other sensors interoperably connected to the device 12.
The microprocessor 22 may also be programmed to implement power-management techniques for the power source 26 to avoid any unnecessary power consumption. In particular, one option is that one or more time window(s) are specified via the antenna 20 for activation of the components in the device 12 to exchange data. Outside the specified time windows, the device 12 may be set into a sleep mode to avoid unnecessary power losses. Such a sleep mode may account for a significant part of the device operation time, the device 12 may as a result be operated over several years without a need for battery replacement.
In particular, according to the present invention, the device 12 utilizes a “sleep” mode to achieve economic usage of the power source 26. In the sleep mode, a portion of the circuitry of the device 12 is switched off. For example, all circuitry may be switched off except for the door sensor 29 and a time measurement unit (e.g., a counter in the microprocessor 22) that measures a sleep time period t.sub.sleep. In a typical embodiment, when the sleep time period has expired or when the door sensor 29 senses a door event, the remaining circuitry of the device 12 is powered up.
When the device 12 receives a signal from the reader 16, the device 12 remains to communicate with the reader 16 as long as required. If the device 12 does not receive a signal from the reader 16, the device 12 will only stay active as long as necessary to ensure that no signal is present during a time period referred to as a radio-signal time period or sniff “period” (“t.sub.sniff”).
Upon t.sub.sniff being reached, the device 12 is powered down again, except for the time measurement unit and the door sensor 29, which operate to wake the device 12 up again after either a door event has occurred or another sleep time period has expired.
In a typical embodiment, the reader-signal time period is much shorter (e.g., by several orders of magnitude less) than the sleep time period so that the lifetime of the device is prolonged accordingly (e.g., by several orders of magnitude) relative to an “always on” scenario.
The sum of the sleep time period and the reader-signal time period (cycle time”) imposes a lower limit on the time that the device 12 and the reader 16 must reach in order to ensure that the reader 16 becomes aware of the presence of the device 12. The related time period will be referred to as the passing time (“t.sub.pass.”)
However, a passing time (“t.sub.pass”) is usually dictated by the particular situation. The passing time may be very long in certain situations (e.g., many hours when the device 12 on a freight container is communicating with the reader 16 on a truck head or chassis carrying the container 10) or very short in other situations (e.g., fractions of a second when the device 12 on the container 10 is passing by the fixed reader 16(C) at high speed). It is typical for all the applications that each of the devices 12 will, during its lifetime, sometimes be in situations with a greater passing time and sometimes be in situations with a lesser passing time.
The sleep time period is therefore usually selected such that the sleep time period is compatible with a shortest conceivable passing time, (“t.sub.pass,min.”) In other words, the relation—
t.sub.sleep.ltoreq.t.sub.pass,min-t.sub.sniff
should be fulfilled according to each operative condition of the device. Sleep time periods are assigned to the device in a dynamic matter depending on the particular situation of the device (e.g., within its life cycle).
Whenever the reader 16 communicates with the device 12, the reader 16 reprograms the sleep time period of the device 12 considering the location and function of the reader 16, data read from the device 12, or other information that is available in the reader 16.
For example, if the container 10 equipped with device 12 is located on a truck by a toplifter, straddle carrier, or other suitable vehicle, the suitable vehicle is equipped with the reader 16, whereas the truck and trailer are not equipped with any readers 16. It is expected that the truck will drive at a relatively-high speed past the fixed reader 16(C) at an exit of a port or a container depot. Therefore, the reader 16(C) on the vehicle needs to program the device 12 with a short sleep time period (e.g., .about.0.5 seconds).
Further ramifications of the ideas outlined above could be that, depending on the situation, the reader 16 may program sequences of sleep periods into the device 12. For example, when the container 10 is loaded onboard a ship, it may be sufficient for the device 12 to wake up only once an hour while the ship is on sea. However, once the ship is expected to approach a destination port, a shorter sleep period might be required to ensure that the reader 16 on a crane unloading the container 10 will be able to establish contact with the device 12. The reader 16 on the crane loading the container 10 onboard the ship could program the device 12 as follows: first, wake up once an hour for three days, then wake up every ten seconds.
In another scenario, the reader 16 is moving together with the device 12 and could modify the sleep time period in dependence on the geographical location. For example, it may be assumed that the device 12 on the container 10 and the reader 16 of a truck towing the container 10 may constantly communicate with each other while the container 10 is being towed. As long as the container 10 is far enough away from its destination, the reader 16 could program the device 12 to be asleep for extended intervals (e.g., one hour.) When the reader 16 is equipped with a Global Positioning System (GPS) receiver or other positioning equipment, the reader may determine when the container 10 is approaching its destination. Once the container approaches the destination, the reader 16 could program the device 12 to wake up more frequently (e.g., every second).
While the above-described power-management method has been explained with respect to the device 12 in the context of trucking of freight containers or other cargo in transportation by sea, road, rail or air, it should be understood for those skilled in the art that the above-described power-management method may as well be applied to, for example, trucking of animals, identification of vehicles for road toll collection, and theft protection, as well as stock management and supply chain management.
Referring now to FIG. 2B, there is shown a first perspective view of the device 12. The device 12 includes a housing 25 containing the data unit 100 (not shown), a support arm 102 extending therefrom, and an antenna arm 104 extending outwardly thereof in an angular relationship therewith. As will be described below, the size of the housing 25, the length of the support arm 102, and the configuration of the antenna arm 104 are carefully selected for compatibility with conventional containers. The housing 25, the support arm 102, and the antenna arm 104 are typically molded within a polyurethane material 23 or the like in order to provide protection from the environment.
Still referring to FIG. 2B, a portion of material 23 of the support arm 102 is cut away to illustrate placement of at least one magnet 27 therein and at least one door sensor 29 thereon. The magnet 27 permits an enhanced securement of the device 12 within the container as described below, while the door sensor 29 detects variations in pressure along a sealing gasket (not shown) of the container discussed below.
A second perspective view of the device 12 as illustrated in FIG. 2C, further illustrates the placement of the magnet 27 in the support arm 102. The magnet 27 is positioned within corresponding apertures 27A formed in the support arm 102 and are bonded thereto in a manner facilitating the installation of the device 12.
Now referring to FIG. 2D, a top view of the device 12 is illustrated before any of the molding material 23 has been applied. In this way, the position of the power source 26, the data unit 100, and the antenna 20 are shown more clearly. The device 12 includes the data unit 100 and power source 26, the microprocessor 22 (not shown), the memory 24 (not shown), and the optional interface 28 (not shown). The support arm 102 extends from the data unit 100 and includes the apertures 27A to house the at least one magnet 27 as well as a support surface to which the door sensor 29 is attached. Extending from the support arm 102 is the antenna arm 104 for supporting the antenna 20.
Now referring to FIG. 2E, a side view of the device 12 before any of the molding material 23 has been applied is illustrated. As shown, the support arm 102 extends upwardly and outwardly from the data unit 100. The support arm 102 is relatively thin and substantially horizontal, although other configurations are available. As more clearly indicated in FIG. 2E, the antenna arm 104 extends angularly from the support arm 102.
Referring now to FIG. 2F, there is shown a front view of the device 12 after the molding material 23 has been applied. The device 12 is illustrated with the molded material 23 that forms the housing 25 encapsulating the device 12. The molding material 23 extends from the antenna arm 104 across the support arm 102 and around the data unit 100. The particular shape and configuration shown herein is but one embodiment of the device 12 and no limitation as to the precise shape of the device 12 is suggested herein.
Referring now to FIG. 2G, there shown a back view of the device 12 according to FIG. 1A. The angular configuration of the antenna arm 104 is likewise seen in a more simplified format for purposes of illustration in FIGS. 2H and 21, which represent bottom and top views of the device 12.
FIG. 2J illustrates a front view of the device 12 as installed on the container 10. The container 10 is shown with a door 202 of the container 10 in an open position to show the orientation of the device 12 in greater detail. The device 12 is mounted to an area adjacent to the door 202 of the container 10. The device 12 may be mounted via a magnetic connection (as previously illustrated), an adhesive connection, or any other suitable connection, on a vertical beam 204 of the container 10. As can be seen in FIG. 2J, the device 12 is mounted so that, when the door 202 is closed, the antenna arm 104 is located on the exterior of the container 10, the door sensor 29, located within the support arm 102, is directly adjacent to a portion of the door 202, and the data unit 100 is located on the interior of the container 10. The device 12 may detect, via the door sensor 29, deviations of pressure to determine whether a door event (e.g., relative and/or absolute pressure change) has occurred. The device 12 may transmit data relative to the status of the door 202 via the antenna 20 to the server 15 as previously described. In addition, the interface 28 may be connected to any number of the external sensors 208 in order to capture information relative to internal conditions of the container 10 and the information obtained via the sensor 208 transmitted to the server 15.
Remaining with FIG. 2J, the device 12 is oriented within the container 10 so that the data unit 100 is disposed within a generally C-shaped recess or channel 206. The support arm 102, including the door sensor 29, extends across the vertical beam 204 between it and a portion of the door 202. When the door 202 is closed, pressure is maintained at the door sensor 29. When the door 202 is opened, the pressure is relieved, thereby alerting the microprocessor 22 that a door event has occurred. An electronic security key stored in the memory 24 will be erased or changed to indicate a “broken” seal or tampering event.
FIG. 2K is a perspective view of the device 12 of FIG. 2D as installed on the container 10. The device 12 is shown attached to the vertical beam 204 so that the door sensor 29 (not shown) within the support arm 102 is adjacent to the vertical beam 204, the antenna arm 104 is positioned in an area of the hinge channel of the container 10, and the data unit 100 is positioned inside the C-channel 206 of the container 10. As more clearly shown herein, the antenna arm 104 protrudes from the support arm 102 to an area substantially near the hinge portion of the container 10 in order to remain on the exterior of the container 10 when the door 202 is closed.
By placing the data unit 100 on the interior of the container 10, opportunities for tampering and/or damage to the device 12 are reduced. Because the data unit 100 is disposed in the C-channel 206, even though the contents of the container 10 may shift during transport, the contents are not likely to strike or damage the device 12.
Although the above embodiment is shown as a single unit including at least one sensor and an antenna 20 for communicating with the reader 16, the present invention may be implemented as several units. For example, a light, temperature, radioactivity, etc. sensor may be positioned anywhere inside the container 10. The sensor takes readings and transmits the readings via BLUETOOTH, or any short range communication system, to an antenna unit that relays the readings or other information to the reader 16. The sensors may be remote and separate from the antenna unit. In addition, the above embodiment illustrates a device 12 that includes a door sensor 29 for determining whether a security breach has occurred. However, an unlimited variety of sensors may be employed to determine a security breach in place of, or in addition to, the door sensor 29. For example, a light sensor may sense fluctuations in light inside the container 10. If the light exceeds or falls below a predetermined threshold, then it is determined a security breach has occurred. A temperature sensor, radioactivity sensor, combustible gas sensor, etc. may be utilized in a similar fashion.
The device 12 may also trigger the physical locking of the container 10. For instance, when a reader 16 secures, via a security request, the contents of the container 10 for shipment, the microprocessor 22 may initiate locking of the container 10 by energizing elecromagnetic door locks or other such physical locking mechanism. Once the container is secured via the security request, the container 10 is physically locked to deter theft or tampering.
As shown in FIG. 3A, the reader 16 includes a short range antenna 30, a microprocessor 36, a memory 38, and a power supply 40. The short range antenna 30 achieves the wireless short-range, low-power communication link to the device 12 as described above with reference to FIG. 2A. The reader 16 may include or separately attach to a device that achieves a link to a remote container-surveillance system (e.g., according to GSM, CDMA, PDC, or DAMPS wireless communication standard or using a wired LAN or a wireless local area network WLAN, Mobitex, GPRS, UMTS). Those skilled in the art will understand that any such standard is non-binding for the present invention and that additional available wireless communications standards may as well be applied to the long range wireless communications of the reader 16. Examples include satellite data communication standards like Inmarsat, Iridium, Project 21, Odyssey, Globalstar, ECCO, Ellipso, Tritium, Teledesic, Spaceway, Orbcom, Obsidian, ACeS, Thuraya, or Aries in cases where terrestrial mobile communication systems are not available.
The reader 16 may include or attach to a satellite positioning unit 34 is for positioning of a vehicle on which the container 10 is loaded. For example, the reader 16 may be the mobile reader 16(B) attached to a truck, ship, or railway car. The provision of the positioning unit 34 is optional and may be omitted in case tracking and positioning of the container 10 is not necessary. For instance, the location of the fixed reader 16(C) may be known; therefore, the satellite positioning information would not be needed. One approach to positioning could be the use of satellite positioning systems (e.g., GPS, GNSS, or GLONASS). Another approach could be the positioning of the reader 16 utilizing a mobile communication network. Here, some of the positioning techniques are purely mobile communication network based (e.g., EOTD) and others rely on a combination of satellite and mobile communication network based positioning techniques (e.g., Assisted GPS).
The microprocessor 36 and the memory 38 in the reader 16 allow for control of data exchanges between the reader 16 and the device 12 as well as a remote surveillance system as explained above and also for a storage of such exchanged data. Necessary power for the operation of the components of the reader 16 is provided through a power supply 40.
FIG. 3B is a diagram of a handheld reader 16(A) in accordance with the principles of the present invention. The handheld reader 16(A) is shown detached from a mobile phone 16(A1). The handheld reader 16(A) communicates (as previously mentioned) with the device 12 via, for example, a short-range direct sequence spread spectrum radio interface. Once the handheld reader 16(A) and the device 12 are within close range of one another (e.g., <100 m), the device 12 and the handheld reader 16(A) may communicate with one another. The handheld reader 16(A) may be used to electronically secure or disarm the container via communication with the device 12. The handheld reader 16(A) may also be used to obtain additional information from the device 12 such as, for example, information from additional sensors inside the container 10 or readings from the door sensor 29.
The handheld reader 16(A) shown in FIG. 3B is adapted to be interfaced with a mobile phone shown as 16(A1) or PDA. However, as will be appreciated by those having skill in the art, the handheld reader 16(A) may be a standalone unit or may also be adapted to be interfaced with, for example, a personal digital assistant or a handheld or laptop computer. The reader 16 draws power from the mobile phone and utilizes Bluetooth, or any similar interface, to communicate with the mobile phone.
Additional application scenarios for the application of the device 12 and reader 16 will now be described with respect to FIGS. 4-8. Insofar as the attachment and detachment of the reader 16(B) to different transporting or transported units is referred to, any resolvable attachment is well covered by the present invention (e.g., magnetic fixing, mechanic fixing by screws, rails, hooks, balls, snap-on mountings, further any kind of electrically achievable attachment, e.g., electro magnets, or further reversible chemical fixtures such as adhesive tape, scotch tape, glue, pasted tape).
FIG. 4 shows a first application scenario of the device 12 and the reader 16. As shown in FIG. 4 one option related to road transportation is to fix the reader 16 to the gate or a shipping warehouse or anywhere along the supply chain. In such a case, the reader 16 may easily communicate with the device 12 of the container 10 when being towed by the truck when exiting the shipping area. Another option is to provide the reader 16 as a handheld reader 16(A) as described above and then either scan the device 12 as the truck leaves the area or carry the hand-held reader 16(A) within the cabin of the truck during surveillance of the container 10.
FIG. 5 shows a second application scenario for the device 12 and the reader 16 as related to rail transportation. In particular, FIG. 5 shows a first example where the reader 16 is attachably fixed along the rail line for short-range wireless communication to those containers located in the reach of the reader 16. The reader 16 may then achieve a short range communication with any or all of the devices 12 of the containers 10 that are transported on the rail line.
The same principles apply to a third application scenario for the container surveillance components, as shown in FIG. 6. Here, for each container to be identified, tracked, or monitored during sea transport, there must be provided a reader 16 in reach of the device 12 attached to the container 10. A first option would be to modify the loading scheme according to the attachment schemes for the wireless communication units. Alternatively, the distribution of the readers 16 over the container ship could be determined in accordance with a loading scheme being determined according to other constraints and parameters. Again, the flexible attachment/detachment of readers 16 for the surveillance of containers allows to avoid any fixed assets that would not generate revenues for the operator. In other words, once no more surveillance of containers is necessary, the reader 16 may easily be detached from the container ship and either be used on a different container ship or any other transporting device. The reader 16 may also be connected to the AIS, based on VHF communication, or Inmarsat satellites, both often used by shipping vessels.
While above the application of the inventive surveillance components has been described with respect to long range global, regional or local transportation, in the following the application within a restricted area will be explained with respect to FIG. 7.
In particular, the splitting of the short range and long range wireless communication within a restricted area is applied to all vehicles and devices 12 handling the container 10 within the restricted area such as a container terminal, a container port, or a manufacturing site in any way. The restricted area includes in-gates and out-gates of such terminals and any kind of handling vehicles such as top-loaders, side-loaders, reach stackers, transtainers, hustlers, cranes, straddle carriers, etc.
A specific container is not typically searched for using only a single reader 16; rather, a plurality of readers 16 spread over the terminal and receive status and control information each time a container 10 is handled by, for example, a crane or a stacker. In other words, when a container passes a reader 16, the event is used to update related status and control information.
FIG. 8 illustrates a flow diagram of a securing process in accordance with an embodiment of the present invention. First, at step 800, identification is requested from the device 12 by the reader 16. At step 802, the device 12 transmits the identification to the reader 16 and, at step 804, the reader 16 selects a container 10 to secure. A request is sent from the reader 16 to the server 15 at step 806. At step 808, the server 15 generates a security key and encrypts the security key with an encryption code. At step 810, the encrypted security key is transmitted to the device 12 via the reader 16 in order to secure the container 10. At step 812, the security key is decrypted and stored in the device 12. A similar procedure may be initiated to disarm the container 10. The container 10 may be secured automatically when passing in range of a reader 16, or a user may secure or disarm specific chosen containers 10 at a time.
FIG. 9 illustrates a security-check process in accordance with an embodiment of the present invention. At step 900, the reader 16 transmits a challenge to the container 10 in question. At step 902, the device 12 of the container 10 generates a response using a security key and an encryption code. At step 904, the response is sent from the device 12 to the reader 16. At step 906, the reader 16 also sends a challenge to the server 15. The challenges to the server 15 and the device 12 may be transmitted substantially simultaneously or at alternate points in time. The server 15 generates and sends a response utilizing the security key and an encryption code to the reader 16 at steps 908 and 910 respectively. At step 912, the reader 16 determines if the responses are equal. If the responses are equal, then the container 10 remains safely secured. Alternatively, if the responses are not equal, then a security breach (i.e., door event) of the container 10 has occurred. Similarly to the securing and disarming processes, a security-check may be performed automatically as the container 10 passes in range of a reader 16 or a user may initiate a security-check at any time during transport.
Referring now to FIG. 10, a flow diagram of a calibration and filter process that may be used in connection with the door sensor 29 is illustrated. A flow 1000 begins at step 1002. At step 1002, the door sensor 29 is activated to sense the distance between a door of the container and the frame every 0.5 seconds, although other time increments may be implemented. The distance is read from the door sensor 29 at step 1004. The sensor obtains an analog value which is then converted at step 1006 to a digital distance value. In this embodiment, the distance value has a resolution of 0.1 mm, although it is possible for other resolutions to be used.
In an alternative embodiment, the door sensor 29 measures an opening angle between the door and the frame. The angle is read from the door sensor 29 at step 1004 which is then converted to a digital distance value at step 1006. In this embodiment, the distance value has a resolution of 0.1 mm, although other resolutions may be used. Also, in some embodiments, the door sensor 29 may include a sensor for sensing the angle and a sensor for sensing the distance. Regardless of which type of door sensor is used, the process then continues to step 1008.
At step 1008, it is determined whether the door sensor 29 is currently in an armed state (i.e., whether a container on which the door sensor 29 has been placed has been secured). If the door sensor 29 is not armed, then the door status is updated at step 1010. From step 1010, execution proceeds to step 1012, at which the execution ends. If the door sensor 29 is armed, then it is determined at step 1014 whether the door sensor 29 was previously armed. If the door sensor 29 was not previously armed, then at step 1016, an armed reference value is set. The armed reference value is a value that is set during calibration of the device and acts as a reference for determining the status of the door sensor 29. If the door sensor 29 was previously armed, then at step 1018 the new distance value (from step 1006) is added to the armed reference value.
From both step 1016 and step 1018, execution proceeds to step 1020. At step 1020, increases in alarm values and alarm times are calculated when the distance value is periodically changing due to racking, which is described below in reference to FIG. 11.
Turning now to FIG. 11, the increase in alarm limits due to racking will be described. Racking occurs when the container is on a ship at sea. Because of the movement of the ship, the container shifts position and the distance value periodically changes. The movement at sea is a slow, periodic movement that is very different from the type of movement associated with opening a door. FIG. 11 illustrates a subroutine 1100 used to increase or decrease the alarm limit so that racking does not set off a false alarm.
At step 1101, the subroutine begins by calculating a delta value. The delta value is calculated by taking the difference between the distance value of step 1006 in FIG. 10 and the armed reference value and then dividing that difference by limit.sub.-2_delta, which is a value that is configured in the sensor prior to the shipping of the container. In one embodiment, the limit.sub.-2_delta is set at 4 mm, although other values may also be used. At step 1102, a mean value for delta is calculated and at step 1104, a mean value for the absolute value of delta is calculated. The mean of the absolute value of delta could vary from the mean of delta because delta could be negative. For example, if the racking is truly periodic, such that the changes in value creates a sine wave, then the mean of delta would be zero. However, the mean of the absolute value would be the amplitude of the sine wave.
Next, at step 1106, the absolute value of the mean of delta is subtracted from the mean of the absolute value of delta to calculate the increase factor. If it is determined, at step 1108, that the increase factor is less than one, then the process continues to step 1110 and the limit increase is calculated by multiplying the increase factor by 2 mm. In other embodiments, a different value could be used. If, at step 1108, it is determined that the increase factor is greater than one, then the process continues to step 1112, and sets the limit increase at 2 mm. In some embodiments a value other than 2 mm could also be used in step 1112. The value may or may not be the same as the value used in step 1110.
After the limit increase is calculated, the subroutine returns to the main routine in FIG. 10, at step 1022. At step 1022, the limit increase is added to the armed reference value to create an upper alarm limit. Also at step 1022, the limit increase is subtracted from the armed reference to create a lower alarm limit. At step 1024, a tamper subroutine will be run, which is described in reference to FIG. 12.
Referring now to FIG. 12, a tamper evaluation subroutine 1200 is illustrated. In the subroutine 1200, one pair of distance and time limits are used; however, any other appropriate number of pairs of distance and time limits may be used. The tamper evaluation subroutine 1200 is initiated at step 1202. At step 1202, a determination is made whether the distance value is less than the lower alarm limit. If, at step 1202, the distance value is not less than the lower alarm limit, a first counter is cleared at step 1204. If at step 1202, the distance value is less than the lower alarm limit, than the first counter is incremented by one at step 1206.
After either step 1204 or step 1206 is performed, the process advances to step 1208. At step 1208 it is determined whether the distance value is greater than the upper alarm limit. If the distance value is not greater than the upper alarm limit, then a second counter is cleared at step 1210. If the distance value is greater than the upper alarm limit, then the second counter is incremented by one at step 1212. After either step 1210 or step 1212, step 1214 is performed and it is determined whether the first counter is greater than a first time value. At step 1214 it is also determined whether the second counter is greater than a second time value. The first and second time values are values that are preset in the door sensor 29 when the door sensor 29 is configured. If the first counter is greater than the first time value or the second counter is greater than the second time value, a determination of tampering is made at step 1216. If the first counter is not greater than the first time value and the second counter is not greater than the second time value, then the subroutine ends.
Although embodiment(s) of the present invention have been illustrated in the accompanying Drawings and described in the foregoing Detailed Description, it will be understood that the present invention is not limited to the embodiment(s) disclosed, but is capable of numerous rearrangements, modifications, and substitutions without departing from the invention defined by the following claims.

## Claims

1. A device for determining whether a security breach of a container has occurred, the container including a door and a frame, the device comprising:
a door sensor;
an interface for attachment of an additional sensor to monitor an internal condition of the container;
a microprocessor coupled with the interface and configured to discern a door event from the door sensor, wherein the door event includes at least opening the door after the container has been secured,
wherein the sensor is configured to sense at least one of a distance value and an angle value that separates the door from the frame.

2. The device of claim 1, farther comprising:
a memory coupled with the microprocessor; and
an antenna configured to exchange data between the microprocessor and a reader.

3. The device of claim 2, farther comprising:
a housing containing the microprocessor;
a support arm extending therefrom; and
an antenna arm extending outwardly from an end of the support arm in an angular relationship therewith.

4. The device of claim 3, wherein the antenna arm is configured to be positioned in an area of a hinge channel of the container.

5. The device of claim 3, wherein the housing includes a data unit configured to be positioned in a C-channel of the door.

6. The device of claim 3, wherein the support arm comprises: a support surface to which the door sensor is attached.

7. The device of claim 1, wherein the sensor is configured to sense, as an analog value at predetermined time increments, a distance between the door and the frame, and wherein the microprocessor is further configured to convert the sensed analog value to a digital distance value.

8. The device of claim 1, wherein the sensor is configured to measure an opening angle between the door and the frame, and
wherein the microprocessor is configured to convert the measured opening angle to a digital distance value.

9. The device of claim 2, wherein an armed reference value is stored in the memory, and wherein the armed reference value is a value that is set during calibration of the device and acts as a reference for determining a status of the sensor.

10. The device of claim 3, wherein the support arm further comprises an aperture configured to house a magnet.