ALARM SYSTEM FOR MOBILE OBJECTS

Abstract: Alarm system for mobile objects comprising a receiver station, a navigation unit located at the mobile object and operable to determine the position of the object, a radio telephone type transmitter unit to be located on the mobile object and operatively connected to the navigation unit, the transmitter unit being operable to transmit signals receivable by the receiver station and indicative of the instantaneous position of the object as determined by the navigation unit. The navigation unit is operable to continuously or after pre-set time intervals to determine the instantaneous position of said mobile object, compare the instantaneous position with at least one predetermined position, and in case of difference between the instantaneous position and said predetermined position to activate the transmitter unit to transmit the instantaneous position to the receiver station, preferably a mobile telephone.

Description: Alarm System for Mobile Objects The present invention relates to an alarm system for mobile objets as described in the introductory part of claim 1. Different locating systems for vehicles are known where the position of the vehicle is determined from signals received from orbiting navigational satellites, for example the Global Positioning System, GPS. These locating systems are used by central control stations to track lorries during their travel through countries and continents. Such a system is disclosed in international patent application WO 89/12935. A central station receives upon request the position of the vehicle from a navigation system and a telephone transmitter located on the vehicle. This system, however, reveals its position only after being called from the central station. Therefore, the system is not optimal for use as an alarm system for vehicles in case of theft of the vehicle, where the position of the vehicle should be transmitted instantaneously and without request. An alarm system for vehicles is disclosed in patent application GB 2 270 405, where the system is fixed to a vehicle and can be activated by a remote transmitter. When set, it records its position using GPS. If the property is stolen and the position changes from an initial position, it communicates its instantaneous position back to a pre-set telephone number by speech synthesis or data link. In this alarm system, it is foreseen, that only one position is used as the initial reference to determine whether the vehicle is moved according to theft. It is not possible to use this system as an alarm system, where a vehicle departs from a predetermined geographical area extending beyond the region characterised by one GPS co-ordinate. It is an object of the invention to provide an alarm system that automatically transmits the instantaneous position of a mobile system, such as a vehicle, in case that the vehicles position differs from one or a plurality of predetermined locations. According to the present invention, this is achieved by an alarm system as mentioned by way of introduction and described in the characterising part of claim 1. The invention can be used for any moving object, for example vehicles, boats, aeroplanes, containers or suitcases. In the following, the invention will be described in the case of a vehicle, however, this should not limit the scope of the invention. The system according to the invention is an alarm system which is combined with a tracking system. If for a vehicle, such as a car, a truck, or construction machinery a certain route for transport or working area is foreseen, this route or working area is stored as a plurality of predetermined positions in a memory in connection with the navigation unit. The navigation unit determines the instantaneous location of the vehicle and a processor compares it with the predetermined positions stored in the memory. If the vehicles position differs from the prescribed route or working area, an alarm is triggered and a pre-set telephone number is called, whereby the position of the ve- hide is transmitted, eventually together with an alarm message and a vehicle identification. A vehicle identification is useful if the same receiver station is surveying several vehicles. The GPS system for civil use is only precise within about 150 meters, so that small deviations from the route, as a stop at a restaurant, would not trigger the alarm. Alternatively, the alarm is only triggered, if the deviation from the predetermined positions is more than a pre-set distance, for example 500 m or 10 km. Because an alarm only is triggered and the position is only transmitted when the posi- tion of the vehicle differs from the predetermined co-ordinates, a surveying system according to the invention is much simpler than corresponding systems of prior art, where co-ordinates of a vehicle are transmitted also in case of no alarm, which requires handling of a much larger amount of data. In case that only one position is predetermined in the navigation unit, the alarm is triggered, when the vehicle is moved outside a radius as determined by the precision of the GPS system. In this case, the alarm system functions as an theft alarm followed by a tracking system for the unauthorised moving of the vehicle. The alarm system is installed in an invisible place, so a thief stealing the vehicle may not be aware of the alarm system and can be caught far from the initial location and where he might feel himself safe. Furthermore, the system as installed on the vehicle is equipped with a power supply and therefore independent of the power supply for the vehicle. According to a further embodiment of the invention, the receiver station comprises a mobile telephone, preferably connected to the Global System for Mobile Communication, GSM. This is a very simple but extremely useful embodiment of the invention. In case a vehicle is stolen, the owner of the telephone is called and the position of the vehicle, eventually together with an alarm message is given to the owner of the tele- phone, who also may be the owner of the vehicle. When the stolen vehicle is followed thereupon, the mobile phone can be carried along helping to reveal the route of the stolen vehicle, which is a great help in chasing the thief in the vehicle. The mobile telephone can be used to transfer the co-ordinates into an external computer which shows the position on a map and fiirther details of the route. Showing of the map may be combined with zooming functions in order to allocate several vehicles and their mutually relative positions. According to a further embodiment of the invention, the instantaneous position comprises terms of longitudinal and latitudinal co-ordinates. These co-ordinates are uni- versal in the sense, that they can serve for further calculations of the already driven route, the speed of the vehicle and the eventual destination. According to a further embodiment of the invention, said transmitted instantaneous position comprises terms of geographical names. The processor in connection with the navigation unit according to this embodiment is capable from an internal electronic register and the calculated GPS co-ordinates to find a corresponding geographical name of the instantaneous position. A geographical name is, for example, the name of the road, the town, and/or the state. The processor in connection with the navigational unit is programmable as to how precise the geographic information to be transmitted should be. Furthermore, the alarm system stores in the memory position points of the route on which the vehicle has been driven. The route can be read from the memory at the receiver station. According to a further embodiment of the invention, said transmitted signals comprise a message via the so-called Short Message Service, SMS. This form for position transmission is especially simple in use. SMS messages can be transferred to a tele- phone even when the owner is communicating to a third person through the telephone. Therefore, an alarm in the form of an SMS message will be recognised by the owner of telephone even when he is in the middle of a very long-lasting telephone conversation. Thus, the owner of the telephone has the possibility to react immediately upon theft of the vehicle. When the stolen vehicle is followed thereupon, the mobile phone can be carried along helping to reveal the route of the stolen vehicle, which is a great help in tracking the vehicle. According to a further embodiment of the invention, said transmitted instantaneous position comprises indications on a map. This embodiments helps the tracking of the vehicle. According to a further embodiment of the invention, said receiver station is a mobile telephone operable to comprise Wireless Application Protocol technology, WAP, for illustrating the instantaneous position on a map on the display of said telephone. Thereby, it is possible to utilise the versatility of the Internet together with the alarm system according to the invention. Utilising this technology, the advantage of the mobility of the mobile telephone, for example during the above-mentioned chasing of the thief in the vehicle, is combined with the advantage of having a map. Especially in regions not so well-known to the owner of the telephone, a map of the area where the vehicle is located is extremely useful. Eventually, the chasing vehicle is equipped with a GPS system as well, in which case the positions of the chasing vehicle and of the stolen vehicle are marked on a map, which facilitates the chasing of the thief in the stolen vehicle. According to a further embodiment of the invention, said alarm system is switchable between an armed and an disarmed state, wherein the navigation unit is operable only in said armed state. It is useful to the owner or the user of the vehicle that he can decide himself, whether the alarm shall be triggered and position of the vehicle shall be transferred or not. However, it should not be possible for a thief to disarm the alarm system. Therefore, the alarm system can only be armed or disarmed with a special security code, or likewise. The arming or disarming of the alarm system can, for ex- ample, be performed by a remote transmitter, which works in near vicinity of the vehicle and which is well-known in alarm systems due to prior art. An alternative for arming or disarming the alarm system is by a communication link from a mobile phone, for example by DTMF tones or by SMS messages. The owner of the vehicle may call the alarm system on the vehicle and through a prescribed code arm the alarm system. The transmitter/receiver part of the alarm system on the vehicle is active at all times, only the navigation unit is not operable in the disarmed state of the alarm system. As a further alternative, the alarm system may be armed or disarmed by a switch located in the vehicle, preferably at a hidden place. According to a further embodiment of the invention, said transmitted signals comprise speech synthesis. According to a further embodiment of the invention, said alarm system is operably connected to measuring devices on the mobile unit, preferably a vehicle, for receiving parameters concerning the functioning of the vehicle and for transmitting said parameters to said receiver station. Along with the co-ordinates of the vehicle, it is possible for the receiver station to receive data concerning the functioning of the vehicle, for example the speed of the vehicle, the amount of fuel left in the tank of the vehicle, or the temperature of refrigerators on the vehicle. According to a further embodiment of the invention, said alarm system is operably connected to adjustment devices for influencing the functioning of the mobile unit, preferably a vehicle, for example starting the heater in the vehicle before the vehicle is accessed, illuminating light or alarm flash lights or distort the ignition system in order to slow or even stop the car in case of theft. The invention will be explained more in detail with reference to the drawing where FIG. 1 is a schematic illustration of the alarm system, FIG. 2 is a schematic illustration of the box with the navigation system and the telephone type transmitter, FIG. 3 shows schematically the method used in the alarm system according to the invention. FIG. 1 is a schematic illustration of the alarm system. In a vehicle 1 , a navigation sys- tem and a telephone type transmitter/receiver is installed in a box 2 at a hidden location on the vehicle 1. In case of alarm, signals revealing the instantaneous position of the vehicle are transmitted, for example by a generally accessible public telephone network 3 to a receiver station, in this case a mobile telephone 4. In case that this pre-set number is not reached, a second pre-set number is called. It is possible to call different telephones dependent on, whether a connection is reached or not. Also, it is possible to program the processor in the alarm system to call several telephone numbers in case of an alarm, for example the owner, the ensurance and the police. It is also possible to program the processor unit of the alarm system to reveal the co-ordinates of the vehicle in case the alarm system is called from a telephone with a pre-stored number. FIG. 2 is a schematic illustration of the alarm system with the navigation unit 5 and the telephone type transmitter/receiver 6 connected with a processor 7 through suitable interfaces 12. The navigation unit 5 receives position co-ordinates from the GPS system through a corresponding antenna 8. The telephone type transmitter/receiver 6 is electrically connected to an antenna 9 for the accessible telephone network, for example GSM. The alarm system further comprises a register 10 for storing predetermined position co-ordinates, actual co-ordinates, eventual parameters of the functioning of the vehicle, and/or other suitable parameters for the proper functioning of the alarm system. The register 10 is accessible for reading and writing through the processor 10 and telephone type transmitter/receiver 6. The processor 10 is according a further embodiment of the invention system capable of measuring and/or influencing the functioning of the vehicle 1. Through further interfaces (not shown), it is possible for the processor 7 to receive data concerning the functioning of the vehicle 1. These data can through the telephone type transmitter/receiver 6 be transmitted to the receiver station 4. On the other hand, the processor 7 can receive instructions from the receiver station 4 to influence the functioning of the vehicle. The method used in the alarm system according to the invention is shown in more detail in FIG. 3. After an arming 13 of the alarm system in the vehicle 1, GPS signals are received 14 by the navigation unit 5 and the instantaneous position is calculated 15 and compared 16 with a possible predetermined position. If there is congruence between the instantaneous and the predetermined position, new GPS signals are received 14 after a certain time interval and the new position is calculated 15. This procedure is repeated unless the instantaneous position is not in agreement with the possible predetermined position, which causes an alarm 17. In that case, the pre-set telephone number is called 18 and the position of the vehicle is transmitted. In case that the telephone is not reachable, further telephones can be called 19.

Claims: CLAIMS 1. Alarm system for mobile objects comprising - a receiver station, - a navigation unit to be located at the mobile object and operable to determine the position of said mobile object by reference to orbiting navigational satellites, - a radio telephone type transmitter unit to be located on said mobile object and opera- tively connected to said navigation unit, said transmitter unit being operable to transmit signals receivable by said receiver station and indicative of the instantaneous position of said mobile object as determined by said navigation unit, characterised in that said navigation unit is operable to continuously or after pre-set time intervals to determine said instantaneous position of said mobile object, compare said instantaneous position with at least one predetermined position, and in case of difference between said instantaneous position and said predetermined position to activate said transmitter unit to transmit said instantaneous position to said receiver station. 2. Alarm system according to claim 1 characterised in that said receiver station comprises a mobile telephone. 3. Alarm system according to claim lor2characterised in that said instantaneous position comprises terms of longitudinal and latitudinal co-ordinates. 4. Alarm system according to claim l-3characterised in that said transmitted instantaneous position comprises terms of geographical names. 5. Alarm system according to claim l-4characterised in that said transmitted signals comprise SMS signals. 6. Alarm system according to claim l-5characterised in that said transmitted instantaneous position comprises indication on a map. 7. Alarm system according to claim l -6characterised in that said receiver station is a mobile telephone operable to comprise WAP technology for illustrating said instantaneous position on a map on a display of said telephone. 8. Alarm system according to claim 1 - 7 characterised in that said alarm system is switchable between an armed and an disarmed state, wherein said navigation unit preferably is operable only in said armed state. 9. Alarm system according to claim 1 - 8 characterised in that said alarm system is operably connected to measuring devices on said mobile unit for receiving parameters concerning the functioning of said mobile unit and for transmitting said parameters to said receiver station. 10. Alarm system according to claim l -9characterised in that said alarm system is operably connected to adjustment devices for influencing the functioning of said mobile unit.

Inventors: JENSEN MIKAEL NOERGAARD, JENSEN, MIKAEL, NOERGAARD
Applicants: DANTRACK APS, JENSEN MIKAEL NOERGAARD, JENSEN, MIKAEL, NOERGAARD
Application year: 2000
Main classification: G01S5
IPC codes: B60R25, G08G1