NAVY BLACK BOX

TECHNICAL FIELD

The invention relates to a device for the detection and recording of mechanical events, and in particular for detecting mechanical events subjected to a marine vessel in order to control a history of mechanical events the marine vessel has been subjected to.

BACKGROUND OF THE INVENTION

When devices or vehicles are un-supervised it is difficult to know if they have been subjected to mechanical forces possibly damaging structures of the devices or vehicles. In many circumstances it is of interest to record what type of mechanical events a device has been subjected to as a function of time or to send an alarm if the device has been subjected to a possibly damaging event.

This is true for instance for boats that are rented or loaned to second party. Boats are easily subjected to damage due to grounds and/or objects located in the water. Normally, when the boat is returned to the owner or care keeper, it has to be examined manually such as by optical inspection either by pulling the. boat ashore or sending a diver into the water in order to do a manual inspection of the hull of the boat. However, this is a costly and time consuming procedure and a more automatic method or system would be of desire.

It has been suggested by the International Maritime Organization regarding performance standards (IMO Resolution A.861(20), 27 November 1997) that different types of information regarding maritime vessels may be recorded using a ship borne voyage data recorded (VDRs). In this document it is discussed to record for instance hull stresses; however, this do not provide any information about the solution used.

It is therefore an object of the present invention to provide a device for monitoring mechanical events which provide an alternative to time and cost consuming inspection of marine vessels.

Further objects of the present invention provide a computer program, a system and a method for monitoring mechanical events.

SUMMARY OF THE INVENTION This is achieved in the following embodiments wherein a first aspect of the present invention, a monitoring device for monitoring mechanical events subjected to a marine vessel is provided, comprising at least one sensing device registering the mechanical events subjected to the vessel, a processor adapted to analyze signals from the sensing device for determining type of mechanical event, a storage unit for storing data indicative of determined mechanical event, and a communication unit for enabling communication to and from said monitoring device, wherein the processor analysis is adapted to determine timing characteristics of the signals obtained from the at least one sensing device (3) adapted to store data indicative of the event together with time of event in the storage unit, characterized in that the timing characteristics are determined as a time duration X between two trigger levels measured on a negative slope in a signal acquired from the sensing device.

The monitoring device may further comprise a location detector and wherein the processor is arranged to store a geographical location obtained from the location detector together with the data. The location detector may be a GPS receiver (Global Positioning System).

The monitoring device may be arranged for communicating at least one of data indicative of a mechanical event, time and position to a receiving device. The communication unit is arranged to communicate using at least one of the following communication transport media: SMS (Short Message Service), MMS (Media Message Service), GSM, GPRS, EDGE, CDMA2000, CDMA, WLAN (Wireless Local Area Networks) technology, WPAN (Wireless Personal Area Networks) technology, and wired communication interface.

The WLAN may comprise at least one of IEEE802.11 and IEEE802.16 based radio network standard protocols and WPAN may comprise at least one of Bluetooth and infrared communication.

The processor may be arranged to distinguish between mechanical events due from the marine vessel hitting a solid object in water and hitting a wave of water, where the

processor determines a mechanical event indicative of hitting a solid object if the time duration between the two trigger levels are below 100 ms, preferable below 10 ms and most preferably below 2 ms.

The monitoring device may further comprise a plurality of sensing devices each of different type registering mechanical events and the processor may be arranged to receive a plurality of signals from the plurality of sensing devices for comparing the sensing signals providing more accurate determination of mechanical events.

Another aspect of the present invention, a computer program for monitoring mechanical events subjected to a marine vessel is provided, comprising: an instruction set for receiving signal data from a sensing device indicative of a mechanical event subjected to the object; an instruction set for obtaining result data from an analysis of said signal data for determining a potentially damaging mechanical event, wherein said analysis comprise determining timing characteristics of said signal data; and an instruction set for storing said result data together with time of event; wherein the timing analysis comprise determining a time duration (X) between two trigger levels measured on a negative slope in a signal acquired from the sensing device.

The computer program may comprise an instruction set for communicating the result data, optionally geographical location and time to a receiving unit. The instruction set for communication may be arranged to use a wireless communication interface. The computer program may further comprise an instruction set for distinguishing between mechanical events due from the boat hitting a solid object in water and hitting a wave of water, where the instruction set determines a mechanical event indicative of hitting a solid object if the time duration between the two trigger levels are below 100 ms, preferable below 10 ms and most preferably below 2 ms.

The computer program may further comprise an instruction set for monitoring the location of said object using a location detection device and an instruction set for sending a signal to a receiving unit if said location deviates from a pre set location or route or sending a signal if the instruction set receives a request for location information.

Yet another aspect of the present invention, a system for monitoring mechanical events subjected to an object is provided, comprising a monitoring device as described above and a reading device receiving data from the monitoring device.

A method for monitoring mechanical events subjected to a marine vessel is also provided, comprising the steps of: reading sensor signal data indicative of mechanical event; analysing type of mechanical event for determining a potentially damaging event; optionally registering geographical position and time of event; and storing at least one of said signal data, position type of event, and time; wherein said analysis comprise determining timing characteristics of said sensor signal data wherein the timing characteristics is determined as a time duration (X) between two trigger levels (601 , 602) measured on a negative slope in a the sensor signal acquired from the sensing device (3).;

The method may further comprise the step of sending the data, geographical position and time to a receiving unit.

Sending may be performed using at least one of following communication transport media: SMS (Short Message Service), Bluetooth, WLAN, GSM, GPRS, UMTS, and WiMax.

The receiving unit may be at least one of mobile phone, personal digital assistance (PDA), dedicated receiving unit, or server.

In yet another aspect of the present invention a marine vessel is provided comprising a monitoring device as described above.

These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

In the following the invention will be described in a non-limiting way and in more detail with reference to exemplary embodiments illustrated in the enclosed drawings, in which:

Fig. 1 illustrates schematically a device according to the present invention;

Fig. 2 illustrates schematically a system using a device from Fig. 1;

Fig. 3 illustrates a method according to the present invention;

Fig. 4 illustrates another method according to the present invention;

Fig. 5 illustrates yet another method according to the present invention; and

Fig. 6 illustrates an example of signal obtained from a sensing device according to the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

Fig. 1 illustrates a monitoring device 1 for detecting and recording mechanical events. This monitoring device 1 comprise a processing unit 2 with a processor 5, a sensor or sensing device 3 for measuring mechanical events, a sensor interface 4, some type of memory unit 6, optionally a location detector 7, power supply 8, communication interface 9, and a communication unit 10.

The sensor 3 measures mechanical events (directly or indirectly), such as vibrations or movement using any suitable measuring technique, including, but not limited to, an accelerometer, a gyroscope, a microphone (or any other sound detector), or radio or sonar based sensors. It can measure indirectly by detecting for instance sound that are indicative of mechanical events, e.g. if a boat hit an object or a rocky part of the bottom of the sea a sound will generally be created, which can be measured or at least detected by a sound detector (microphone). The sensor 3 can also measure mechanical events directly with for instance the accelerometer. More than one type of sensor 3 may be used at the same time in order to further enhance the sensitivity and/or accuracy of the monitoring device 1. This may also provide redundancy to the monitoring device 1 where one sensor can back up if another sensor fails.

The device 1 may be mounted in a vessel or object that is to be monitored over time for if being subject to damaging mechanical events. The monitoring device 1 is to be mounted

rigidly or at least in such a way that mechanical events can be detected. For instance if an accelerometer is used at least part of the mechanical waves propagating in the vessel should be able to be transferred to the accelerometer.

The operation of the monitoring device 1 is as follows in one embodiment: the processor 5 reads at least one signal (or data in relation to the signal) from the sensor 3 via a sensor interface 4. The processor may analyse the data for detection of trigger levels in order to monitor any damaging events for being able to take responsive action and/or it may store data in the memory unit 6. The memory unit 6 can be one or several memory units 6 of one or several different types. Both volatile (e.g. RAM (random access memory) and nonvolatile memory (e.g. hard disks, flash memory, memory stick, EEPROM (electrical erasable programmable read only memory), may be used depending on function or functions present. Optionally a location detector 7 may be present in order to register a location where an event has taken place and/or for recording the path of the vessel or object. Such location detectors may include for instance a GPS (Global Positioning System) receiver. The monitoring device 1 need power to operate which can be supplied via a power supply 8 interface, preferably with a power backup utility (e.g. battery) built in so as to provide power even if an external power source does not supply power to the monitoring device 1. The monitoring device 1 may be arranged to store events of external power interruptions for later analysis.

If a mechanical event has occurred the system may send a response to a receiving unit, such as a server, dedicated receiving device, or mobile phone, this communication may be performed via the communication interface 9 and the communication unit 10. Normally the monitoring device 1 is arranged to store events until it has been reset in an authorized operation. It should not be possible to reset the device 1 un-authorized, this to ensure that the device 1 is not tampered with and potentially damaging mechanical events hidden.

The communication unit 10 may comprise for instance a GSM (Global System for Mobile communication), EDGE (Enhanced Data rates for Global Evolution), or GPRS (General Packet Radio Service) enabled communication device or any other suitable long or short range wireless interface including but not limited to, UMTS, CDMA 2000, CDMA, Bluetooth, IEEE802.11 interface (of any version or flavour), IEEE802.16 interface, or version of these (WiFi and WiMax), MowLAN, and other wireless PAN or LANs (Personal or Local Area Networks). The communication interface/unit may also be a fixed wired

interface utilizing for instance a serial or parallel communication protocol (e.g. Ethernet, token ring, RS232, RS485, IEEE1284, or GPIB (General Purpose Interface Bus)). As other wireless technologies are put to the market they can be utilized in the invention as understood by the person skilled in the art. It may also comprise a combination of long and short range communication units each used for different purposes, e.g. a Bluetooth unit for short range communication with a reading device in harbour and a GSM module for long range communication when using the boat away from home harbour and sending data when an event has triggered the monitoring device 1.

In another embodiment the processor 5 may be adapted to directly read a signal from a sensor 3 and therefore no sensor interface 4 is necessary.

Now the present invention will be illustrated with respect to an embodiment in a boat. Turning to Fig. 2, a boat 20 is illustrated in a harbour and the monitoring device 1 is located within the boat. The monitoring device 1 is arranged to receive and store data indicative of mechanical events as described earlier in this document. A person 21 may acquire readings from the monitoring device 1 using a portable reading and/or controlling unit 22 which receives data when within a suitable distance from the monitoring device 1 and the portable device may be used for controlling the settings and mode of operation of the monitoring device 1. In this way it is possible to acquire knowledge or indications of the events that the boat 20 has been subjected to under use. Since the monitoring device 1 provide such information, it is not necessary to remove the boat 20 from the water 24 for optical inspection unless the monitoring device 1 indicates subjection to events of damaging character. Alternatively, the monitoring device 1 may send data to a server or central monitoring location 25 on a wireless link of some type as discussed earlier. If a triggering event has been detected, the monitoring device may be arranged to contact the above mentioned server or central monitoring location 25 in real time and not to wait until reaching the home harbour. However, the monitoring device can be adapted to wait with such contact until the communication unit has connection with communication services necessary for communication, e.g. a GSM network for GSM communication links. This communication may be operate both from the monitoring device 1 and to the monitoring device 1 , thus providing the possibility to control settings in the monitoring device 1 , such as type of sensors connected to the device 1 , sensitivity, triggering parameters, mode of operation, calibration parameters and so on as understood by the person skilled in the art.

A triggering event may be when analyzed sensor data indicates that a potentially damaging mechanical event has occurred.

If a GPS system has been incorporated within the monitoring device 1 , it can be adapted to send data indicative of the location to a server or central monitoring location 25. This can be useful for monitoring the location of the boat (or any other object with the monitoring device 1 according to the present invention mounted), for instance for locating a stolen boat or for safety reasons to track that the boat is following an intended route. If the boat travels away from such an intended route one may suspect that there is something wrong and appropriate action may be taken (such as contacting persons on the boat, contacting coast guard or rescue teams).

Let us now discuss some modes of operation:

In an embodiment of the monitoring device 1 according to the present invention illustrated in Fig. 3 with a sensor and a GPS, the monitoring device 1 is arranged to have a waiting mode 300 and if a triggering event is measured 301 , the device 1 registers the position and time of the event 302. Two different courses of action can be taken (one or both): the device 1 stores data, time and position 303 and/or sends data, time and position using a suitable communication link type (e.g. SMS) 304. Finally the device returns to the waiting mode 305. Using an SMS communication type, the telephone number is preset within the monitoring device 1. However, other ways of presetting a telephone number may be utilized as understood by the person skilled in the art. This mode of operation is useful for monitoring potentially damaging events in real time and reporting either as a direct response to the event, later when a link can be established, or during an examination period of the vessel during, for instance return of the vessel after a period of renting.

Another embodiment of the present invention is illustrated in Fig. 4, again with a GPS incorporated or connected to the monitoring device 1. The monitoring device 1 is in waiting mode 400 and if the sensor gives a triggering signal 401 the position and time is registered 402 and stored 403. A triggering signal from the sensor may be when a signal level passes a pre set level. Finally the monitoring device returns to the waiting mode 404. In this embodiment the stored events are read at a later time. This embodiment do not take advantage of long range communication of data and it is therefore not necessary to

have a long range communication unit 10 and cost of the monitoring device 1 will be reduced.

Fig. 5 illustrates yet another embodiment of the present invention, again with a GPS enabled monitoring device 1. The monitoring device 1 is arranged to continuously monitor the position (geographical) 500 and storing the position in memory 501. The monitoring device 1 waits a certain time (pre settable) 502 before acquiring a new position 503. With these two positions the monitoring device 1 can analyze any movement 504. If the result is that the boat has moved a distance below a pre set level it returns to wait 505. However, if the distance is larger than the pre set level 506 it sends 507 a signal (for instance to a server, a central monitoring location, or to a mobile phone) indicative of this movement and alerts a monitoring party (e.g. the owner) of an unauthorized movement of the boat. The monitoring device 1 can in this embodiment also be arranged to as a next step enter 508 into a mode as described in relation to Fig. 3. The mode as illustrated by Fig, 5 can be used also for authorized use of the boat of course in order to alert the owner that the boat is now under use and the owner will know when the boat has been collected by someone renting it. A similar type of location monitoring mode of operation is when the location of the boat is measured and compared against a pre set route of the boat. In this manner it is possible to alert an owner if the boat deviates from the pre set route.

The modes described above can be selected by the user of the monitoring device 1 and used each on its own or together with each other in different combinations. It may be possible to set the modes of operation, pre set locations and pre set routes either via an interface located on the monitoring device or via the receiving unit 22 or central server 25. Both the monitoring device 1 and any other device in communication with the monitoring device 1 may be password protected in order to reduce the risk for unauthorized access of the monitoring device 1 occurs. For instance is should not be possible for someone to change pre set levels and routes in the monitoring device 1 without permission.

The same modes of operation can be utilized for other types of objects under surveillance, for instance cars, trucks, planes, and so on as understood by the person skilled in the art.

The modes of operation are conveniently arranged as instruction sets in a software program operated in the processing unit 5 and stored in the memory 6 of the monitoring device.

The monitoring device 1 can further be adapted to draw very little power in order to obtain a long operational life without external power, driven by an internal battery or batteries.

5 Data can also be sent to for instance a server storing any events and/or notifying the owner of the vessel. The server may be located on a public network (e.g. Internet) or private network (e.g. Intranet) and accessible directly, e.g. via an SMS sent to a mobile phone connected to directly to the mobile phone, or via a combination of infrastructure systems, e.g. a GPRS interface connected to the Internet in turn connected to the server.

10

In one embodiment of the present invention, an accelerometer device is used for detecting mechanical events. However, not all mechanical events are potentially damaging so a data need to be analysed in order to determine the type of event and if it is of potentially damaging character. The signal received from the accelerometer will have

15 different characteristics depending on the type of accelerometer; an analogue accelerometer will yield a signal according to Fig. 6. If the signal is larger than a pre set level 601 , the analysis system will measure the time between a downward crossing of the pre set level 601 and a level 602 above the noise level of the system; i.e. the time for the acceleration to decay from the mechanical event. Thus the decision is reduced to

20 determine the time scale of the acceleration event. In the case of a digital accelerometer a signal is obtained from the mechanical event comprising an array of digital characters, e.g. zeros and ones. For instance in one type of digital accelerometer the array comprise of 20 ones (X) together followed by 20 zeros (Y) together when zero acceleration is measured, at a positive maximum measurable acceleration the array comprise 40 ones

25 and at a negative maximum measurable acceleration the array comprise 40 zeros. The array may also comprise control characters in order to know when the signal starts and end, or if any error is detected within the accelerator. In this digital example the ratio between X and Y is determined for each reading and the analysis system determines the speed of ratio change in order to determine if a potentially damaging event has occurred.

30 In both the digital case and the analogue, depending on what type of application, a timing reference level can be determined by calibration and set as a triggering level for when to register a potentially damaging event. In the processing device the signal may be divided for example into 256 steps between inclusive 0 and 255 (where 255 represent 10 G of acceleration). In one exemplifying embodiment the trigger levels are set as the first level

35 601 at ca 30 and the second trigger level 602 above the noise level to ca 2 or 3; however,

it should be understood that these levels 601 , 602 vary depending on type of vessel, accelerometer, type of signal conditioning and so on. The time duration X measured between these two levels is used as discussed earlier for determining the type of mechanical event, for instance a time duration below 100 ms may be used for determining a mechanical event that is potentially damaging for the vessel, in many cases the time duration is below 10 ms and in most cases the time duration is below 2 ms.

Other measuring devices may be used than the above mentioned accelerometer based system. The device 1 may measure a distance to adjacent objects or surrounding areas in order to determine the amount of risk any object with the device mounted has been subjected to; e.g. with a sonar one can measure the distance to objects in or bottom of the sea or lake. If the distance is below a certain level the device is arranged to react in some suitable way, such as record the event and/or send a message using the communication unit 10 with data corresponding to the event.

Combinations of detectors may be utilized in order to receive a more efficient and accurate analysis of signal data.

An object that may be hit by a boat include, but is not limited to, a ground, a shore of the sea, of a man constructed structure (e.g. a pier or a bridge) or natural structure located in relation to the sea, another boat, or debris found in the water (e.g. timber or containers).

With the term boat is meant any type of sea faring vessel of any size and type (e.g. canoe, boat, ship, yacht, submarine, sailing ship, tanker, and so on) and with the term sea is meant any type of water collection wherein a boat may travel (including e.g. sea, lake, river, and tanks and basins for testing marine equipment).

It should be noted that the word "comprising" does not exclude the presence of other elements or steps than those listed and the words "a" or "an" preceding an element do not exclude the presence of a plurality of such elements. It should further be noted that any reference signs do not limit the scope of the claims, that the invention may be implemented at least in part by means of both hardware and software or a combination of these, and that several "means" may be represented by the same item of hardware.

The above mentioned and described embodiments are only given as examples and should not be limiting to the present invention. Other solutions, uses, objectives, and functions within the scope of the invention as claimed in the below described patent claims should be apparent for the person skilled in the art.