WO2009150041A2

WO2009150041A2 - Modular gyro-stabilized surveillance system for mobile carries

Info

Publication number: WO2009150041A2
Application number: PCT/EP2009/056394
Authority: WO
Inventors: Joachim Lorenz
Original assignee: Recon Technology Europe Gmbh
Priority date: 2008-05-26
Filing date: 2009-05-26
Publication date: 2009-12-17
Also published as: WO2009150041A3

Abstract

A modular, gyro-stabilized surveillance system is provided, comprising a removable sensor module incorporating at least one gyro-stabilized surveillance sensor, and a stationary part comprising means for mounting the surveillance system to a carrier, an electronic block for controlling the surveillance system, means for gyro-stabilization by a first axis and a second axis and a movable sensor module holder for holding the sensor module being movable around the first and second axis, wherein the removable sensor module is provided with a housing having a gas-tight seal and incorporating the at least one sensor, wherein the removable sensor module is adapted to be mounted and dismounted from the stationary part in a gas-tight state, means for fixation of the removable sensor module to the stationary part are provided outside the gas- tight seal and electrical connectors are provided outside the gas-tight seal. The invention allows easy replacement of the sensor module in the system.

Description

RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO

Modular gyro-stabilized surveillance system for mobile carries

This invention is directed to a modular gyro-stabilized surveillance system for mobile carriers to land, water and air.

Prior Art

Gyro-stabilized surveillance systems are known to be used for different military and civil applications and include different type of surveillance sensors tailored to the specific needs. The purpose of these systems is to stabilize video pictures under certain conditions by eliminating undiserable effects such as vibrations in different positions of inclination, e.g. in helicopter applications, on boats etc..

The existing surveillance systems only fulfil a stationary requirement profile. The contained cameras and their focal lengths as well as all other sensors are steady components of a single surveillance system.

These "static" surveillance systems do not always correspond to the requirements of an assignment and linked troubleshooting during the application. The integration of other components is not possible under application conditions, e.g. on the free field or in a harbour due to the complexity of integration of sensors and other components within the surveillance system. Especially, the exchange of a sensor, e.g. a camera, in case of a defect demands the dismantling and opening of the whole surveillance system. This opening could only be performed in a workshop using special equipment and by high specialized technicians. The reasons for the high requirements are the high sensitivity of the sensors, with the need of a protective gas atmosphere and the need for exact balancing the movable parts of the system, which is necessary for the gyro-stabilization. Therefore, in the existing surveillance systems, the exchange of a sensor causes loss of time and money and a leg in surveillance. Therefore, there is the need to provide a surveillance system, in which a sensor may be easily replaced by another.

Summary of the Invention

This object is solved by the present invention through providing a modular, gyro-stabilized surveillance system having a sensor module and a stationary module carrying the sensor module, wherein the sensor module can be easily exchanged by another sensor module.

This modular surveillance system enables the user to insert the desired sensor technology into the stationary part of the modular surveillance system in only few minutes. This exchange can be done by a non-skilled person and even under difficult application conditions, e.g. in field or in a harbour. Accordingly, a modular, gyro-stabilized surveillance system is provided, comprising a removable sensor module incorporating at least one gyro-stabilized surveillance sensor, and a stationary part comprising means for mounting the surveillance system to a carrier, an electronic block for controlling the surveillance system, means for gyro-stabilization by a first axis and a second axis and a movable sensor module holder for holding the sensor module being movable around the first and second axis, wherein the removable sensor module is provided with a housing having a RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO gas-tight seal and incorporating the at least one sensor, wherein the removable sensor module is adapted to be mounted and dismounted from the stationary part in a gas-tight state, means for fixation of the removable sensor module to the stationary part are provided on the surface of the removable sensor module outside the gas-tight seal and matching means for fixation are provided on the surface of the sensor module holder, and electrical connectors are provided on the surface of the removable sensor module outside the gas-tight seal and matching electrical connectors are provided on the surface of the sensor module holder.

This modular construction of the gyro-stabilized surveillance system allows the user to exchange the removable sensor module in case of a defect or any other requirement for the sensors under all weather conditions, within short time and without technical knowledge or special tools.

The at least one sensor of the removable sensor module may be gyro-stabilized by said first axis and said second axis through the stationary part. They may be gyro-stabilized by a third axis and fourth axis through further means for gyro-stabilization provided inside said housing. The third and fourth axis have the same orientation as the first and second axis.

Means to facilitate mounting of the removable sensor modules to the movable module holder may be located on the surface of the movable module holder and the removable sensor module in a corresponding location. These means are provided outside the gas-tight seal of the housing. The means to facilitate mounting may be provided outside the gas-tight sealing of the housing and may comprise one or more leading pins on the surface of the sensor module with corresponding holes on the surface of the module holder. The means to facilitate mounting may comprise one or more grooves on the surface of the sensor module for respective tongues formed on the surface of the module holder; and/or an end of a cylinder rod on the surface of the sensor module for receiving a pull-out bolt and a corresponding supporting plane formed on the surface of the module holder.

The means for fixation located on the surface of the housing of the removable sensor module may be fixing screws or self secured fixing screws and the matching means for fixation on the surface of the module holder are corresponding threads. The movable module holder may have the shape of a yoke.

The movable module holder may be provided with at least a first and a second bracket, which are connected movable to a platform-frame.

The supporting plane and/or the hole for leading pins and/or the electrical connectors and/or the threads for fixing screws may be located on at least one of the brackets of the movable module holder.

The centre of gravidity of the entity consisting of the removable sensor modules mounted to the movable module holder may be located on one of the first axis, second axis, third axis or fourth axis and/or the centre of gravidity of the entity consisting of the removable sensor module mounted to the movable module holder and the geometrical centre of the entity may be identical. RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO

The at least one surveillance sensor may be a IR, VIS, UV-camera, a laser range finder, microwave detector, and/or positioning sensors provided in the gas-tight housing.

The housing may comprise a front cover and a back cover each having means for sealing the housing gas-tightly. In addition, a modular gyro-stabilized surveillance system kit is provided, comprising a modular gyro-stabilized surveillance system of the present invention, and at least one additional removable sensor module incorporating the same or different surveillance sensors for replacing the removable sensor module of the gyro-stabilized surveillance system.

Further, a method for exchanging the removable sensor module of the modular surveillance system of the present invention is provided, comprising the steps of providing modular surveillance system of the present invention fixed to a mobile carrier, stopping surveillance, dismounting a first removable sensor module from the movable module holder without opening the gas-tight housing of the removable sensor module while the stationary part remains fixed on the mobile carrier, mounting a second removable sensor module gas-tightly to the movable module holder, and starting surveillance.

The electrical connection between the sensor module and the movable module holder may be provided by a pressing force establish during mounting of the sensor module to the module holder exerted on respective electrical connections on the surfaces of the sensor module and the module holder, respectively. The dismounting step may comprise removing the means for fixation; holding together the sensor module and the module holder by tongues of the module holder provided inside grooves of the sensor module; and exerting a pulling force on the sensor module to dismount the sensor module from the module holder.

Short description of the drawings

The present invention will now be described in more detail with referene to the follwing drawings:

Fig. 1 a modular gyro-stabilized surveillance system of the present invention in a dismounted state; Fig. 2 a schematic view of the opened sensor module of the present invention;

Fig. 3 another view of the opened sensor module of the present invention;

Fig. 4 a third view of the opened sensor module of the present invention;

Fig. 5 a view of the closes sensor module of the present invention;

Fig. 6 a view of the stationary module or part of the present invention; Fig. 7 a view of the modular surveillance system of the present invention in a mounted state;

Fig. 8 a second view of the modular surveillance system of the present invention in a mounted state. RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO

Detailed description of the drawings

The removable sensor module may be easily exchanged against another removable sensor module incorporating the same sensors or further removable sensor modules with different sensors. The sensors in the removable sensor module are built in a gas-tight housing. On the surface of the housing there are means for connecting, holding, fixation, power consumption and electronically communication. The means for connecting, holding, fixation, power consumption and electronically communication are constructed complementary to according means on a movable module holder of the stationary part of the modular surveillance system.

Fig. 1 shows a modular gyro-stabilized surveillance system of the present invention in a dismounted state. Fig. 2 is a schematic view of the opened sensor module of the present invention. Fig. 3 is another view of the opened sensor module of the present invention. Fig. 4 shows a third view of the opened sensor module of the present invention. Fig. 5 is a view of the closes sensor module of the present invention. Fig. 6 provides a view of the stationary module or part of the present invention. Fig. 7 is a view of the modular surveillance system of the present invention in a mounted state. Fig. 8 provides a second view of the modular surveillance system of the present invention in a mounted state.

Fig. 1 shows a schematic drawing of the modular surveillance system in a dismounted state. The system comprises a first module, the sensor module 2, and a second module, the stationary part 3. The stationary part 3 comprises a sensor module holder 17, preferably in the form of a yoke with two arms, on which the sensor module 2 is mounted.

The stationary part 3 as shown in Figs. 6-8 comprises an electronic block 5, with tension care and control of the surveillance system and platform 53 inclusive a platform-frame 7 with the movable module holder 17. The stationary part 3 can be fixed to a mobile carrier, e.g. helicopter, aeroplane, ship or car, whereby the electronic block 5 is preferably located inside the mobile carrier and the platform 53 is applied to the surface of the mobile carrier. After fixing the stationary part 3 to a mobile carrier, the stationary part 3 remains at the vehicle even during an exchange of the removable sensor module 2.

The platform 53 may be rigidly fixed to the mobile carrier by a mounting-plate 6, whereby the connected platform-frame 7 is rotatable around a first axis 49. The preferred shape of the platform-frame 7 is u-shaped. Between the blades of the u-shaped platform-frame 7 the movable module holder 17 is applied. The movable module holder 17 has preferred the shape of a yoke 48. In relation to the platform-frame 7 the movable module holder 17 is movable in a second 50 axis. Thereby the sensors 12 of removable sensor module 2 could be gyro-stabilized by first 49 and second 50 axis when the removable sensor module 2 is connected with the movable module holder 17.

Furthermore the surface of the movable module holder 17 is equipped with means for connecting, holding, fixation, power-support and electronically communication with a removable sensor module 2. These means on the surface of the movable module holder 17 are formed and located in this way that these means fit to the complementary means on the surface of the removable sensor module 2. RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO

The movable module holder 17 has the shape of the segments that are missing to the ball shape of the removable sensor module 2. Combining the movable module holder 17 and the removable sensor module 2, the complementary parts result in a ball-like-structure. In this combined structure - constituted by the movable module holder 17 and the removable sensor module 2 - the balance point and the geometrical centre become essentially identical.

Furthermore the first 49 and second 50 axis cross the balance point of the combined structure.

These features make it is possible to remove a first removable sensor module 2 from the stationary part 3 without opening the gas-tight housing 4 of removable sensor module 2. Further it is possible to mount a second 51 or further 52 removable sensor module with the same or different sensors 12 as the first removable sensor module 2 at movable module holder 17 without opening the gas-tight housings 4 of the second 51 or further 52 removable sensor modules.

With the acquisition of the disclosed modular, gyro-stabilized surveillance system 1 , the user is provided with a base gyro-stabilized surveillance system together with optional second 51 or further removable sensor modules 52 which may contain different combinations of cameras and other sensor technologies. Thus, several pre-manufactured removable sensor modules 2 are available "as a substitute" for the most different applications possibilities.

This modular construction of the gyro-stabilized surveillance system 1 allows the user to exchange the removable sensor module 2 in case of a defect or any other requirement for the sensors 12 under all weather conditions, within short time and without technical knowledge or special tools.

Therefore, just one modular, gyro-stabilized surveillance system 1 can be used for all applications and different tasks, e.g. mounted on a carrier.

The presented drawings and descriptions relate to different exemplary embodiments of the application. In general, the modular, gyro-stabilized surveillance system 1 may comprise cameras, laser detectors, positioning systems and other techniques. The disclosed modular gyro-stabilized surveillance system 1 can be used to land, water, and air, e.g. installed on a mast, on a vehicle or ship.

The modular, gyro-stabilized surveillance system 1 comprises at least two parts, a first removable sensor module 2 and a stationary part 3 (see Fig. 1 ).

First of all, it will be described what is shown in the different figures.

Fig. 2 shows a view of the back cover 8 of the opened housing 4 of the removable sensor module 2 with a pulled-out carriage frame 10 with mounted sensors 12 and electronic components 20 provided on the carriage frame 10. One or more sensors 12 may be mounted on a single carriage frame 10. The back cover 8 is equipped with guides 1 1 for the installation of sensors 12 through the insertion of the carriage frame 10. RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO

Fig. 3 shows a view of the opened housing 4 of the removable sensor module 2. Shown is the isolated back cover 8 of the housing 4. Inside the back cover 8 there are guides 1 1 for the uptake of the carriage frame 10 with sensors 12 not shown in fig. 3. The guides 1 1 are preferably applied movable on a third axis 43 and fourth axis 24 inside the back cover 8. The third and fourth axis 43, 24 may preferably have the same orientation as the first 49 and second 50 gyro-stabilized axis of the platform 53. In combination with the third 43 and fourth 24 axis a fine-tuning of the gyro-stabilization of the sensors 12 is possible, if the removable sensor module 2 is connected with the stationary part 2 of the surveillance system 1. Inside the back cover 8 there is a gyroscope 33 and a torque motor (not shown in fig. 3) provided for the gyro- stabilization of the sensors 12 in the third 43 and fourth 24 axis. At the inner side of the opening of the back cover 8 a gasket 32 is applied. The gasket 32 serves as a gas tight sealing when the back cover 8 is fixed with the front cover 9. Furthermore, at the external side of the opening of the back cover 8 there is a multitude of threads for closing screws 44 provided. The threads for closing screws 44 ensure a gas tight sealing when the back cover 8 is fixed with the front cover 9 by closing screws. On the right side of the back cover there is a protruding cylinder rod 21. The protruding end of the cylinder rod 21 just ends on the surface of the front cover 9 when the front cover 9 is fixed with the back cover 8. Thereby the pull out bolt within the cylinder rod could be easily accessed by the front cover 9 in the case of dismantling the removable sensor module 2. Fig. 4 shows a view of the opened housing 4 of the removable sensor module 2. On the left, the sensors 12 inserted on the carriage frame 10 into the back cover 8 of the housing 4 are shown. On the right, the isolated front cover 9 of the removable senor module 2 is shown. On the side of the front cover 9 a multitude of pits for closing screws 39 is provided. The pits for closing screws serve for the reception of closing screws for the tight fixation of the front cover 9 with the back cover 8. On the surface of the front cover 9 a hatch 34 with optical windows 16 is provided. The hatch 34 with optical windows 16 allows the measurements of the sensors 12 installed behind the windows 16 while the sensors 12 stay in an inert gas atmosphere.

Fig. 5 shows a side view of the backside of removable sensor module 2. Front cover 9 and back cover 8 are fixed together. The shape of the removable sensor module 2 is ball-like with cut- outs at both opposite sides. The cut-outs are completed by complementary parts of the movable module holder 17 when the removable sensor module 2 is fitted into the stationary part 3 of the surveillance system 1.

At the lower part of the back cover 8 a groove 28 for receiving a tongue 45 of the movable module holder 17 is provided. Groove 28 and tongue 45 facilitates the mounting and dismounting of the removable sensor module 2 to or from stationary part 3 of the surveillance system 1.

On the left side of back cover 8 leading pins 38 are arranged. The leading pins 38 fit exactly into matching holes for leading pins 36 which are provided at the movable module holder 17. The leading pins 38 facilitate the accurate mounting of the removable sensor module 2 at the stationary part 3.

Adjacent to the leading pins 38 there may be two fixation screws 31 provided. Two further fixing screws 31 may be provided on the right side of the removable sensor module 2 not shown in fig. 5. The fixing screws 31 enable a fast and secure fixation and fast dismounting of the removable RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO sensor module 2 to or from the movable module holder 17 during mounting or dismounting. In the preferred embodiment, not more than four screws for fixation are used in total.

Two first electrical connectors 19 are provided on the surface of the sensor module 2 outside the gas-tight part of the housing 4. The first electrical connectors 19 have the complementary surface of the second electrical connectors 190 which are provided on the movable module holder 17 in a corresponding location. First 19 and second 190 electrical connectors fit perfectly together when they are pressed together during mounting of the removable sensor module 2 to the movable module holder 17.

Between the first electrical connectors 19 the end 47 of a cylinder rod 21 with a pullout bolt inside (not shown in fig. 5) is located. The pullout bolt facilitates the detachment of the first 19 and second 190 electrical connectors during dismounting removable sensor module 2.

Fig. 6 shows a front view of the stationary part 3 of the surveillance system 1 without the removable sensor module 2. An electronic block 5 is provided at the top, which is preferably located within the mobile carrier. Beneath the electronic block 5 a mounting-plate 6 that fixes the platform 53 at the surface of a mobile carrier is provided. Beneath the mounting-plate 6 there is a platform-frame 7. The platform-frame 7 is attached rotatable in relation to the mounting-plate 6 around the first axis 49. The preferred shape of the platform-frame 7 is a u- shape, wherein the opening of the u-shaped platform-frame 7 shows downwards in fig. 6. Between the blades of the u-shaped platform-frame 7, the movable module holder 17 is located. The movable module holder 17 is preferably a yoke 48 with a first 26 and a second 27 bracket. The shape of the yoke 48 is build in that way that the yoke 48 complements the missing parts of the ball-like structure of the removable sensors module 2, when the removable sensors module 2 is fixed at the yoke 48. The resulting ball-like structure of the entity formed by the removable sensor module 2 and the movable module holder 17 facilitates the gyro-stabilization of the sensors 12. The yoke 48 is attached movable between the blades of the platform-frame 7.

Between the blades of the platform-frame 7 the yoke 48 is able to rotate around the second axis 50. The first axis 49 and the second 50 axis cross in the middle between the first 26 and second 27 bracket. The crossing point of the first 49 and second 50 axis is identical with the centre of gravidity of the entity composed of the modular sensor module 2 and the movable module holder 17, 48. Furthermore, means for gyro-stabilization are provided by the stationary part 3 not shown in fig. 6. By the rotatable platform-frame 7, the rotatable yoke 48 and the means for gyro-stabilization, a gyro-stabilization of the sensors 12 within the removable sensor module 2 is possible, when the removable sensor module 2 is mounted at the stationary part 3.

On the front side 30 of the first bracket 26 of the yoke 48, several means for fixing, mounting, dismounting, and electrically contacting the removable sensor module 2 are located. On the front side of the first bracket 26 a supporting plane 14 for the pullout bolt is located. The supporting-plane 14 facilitates the dismounting of the removable sensor module 2 by receiving the force of the pullout bolt when the pullout bolt is screwed in the direction of the supporting- plane 14. The force of the protruding pullout bolt is useful to cut the connections between the first 19 and second 190 electrical connectors during dismantling the removable sensor module 2. RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO

Above and below of the supporting-plane 14 on the front side of the first bracket 26 second electrical connectors 190 are located. The second electrical connectors 190 fit perfectly into first electrical connectors 19 located on the surface of the removable sensor module 2, when the removable sensor module 2 is mounted to the movable module holder 17, 48. Above and respectively below of first electrical connectors 19 on the front side 30 of the first bracket 26 there are threads 46 for fixing screws 31 located. The threads 46 for fixing screws 31 are arranged for receiving the fixing screws 31 provided by the removable sensor module 2. On the front side of the second bracket 27, threads 46 for fixing screws are located (not shown in fig. 6). Preferably, not more than four threads 46 for fixing screws 31 are necessary for the fixation of the removable senor module 2 to the movable module holder 17. This enables a very fast mounting or dismounting of the removable sensor module 2.

Above and respectively below of the threads 46 for fixing screws 31 on the front side 30 of the first bracket 26 there are two holes 36 for leading pins 38 located. The two holes 36 for leading pins 38 are for receiving the leading pins 31 provided by removable sensor module 2. Furthermore, on the inner surface of the first 26 and second 27 bracket there is a first and second tongue 45 located. The first and second tongue 45 is for introduction of the tongues 45 into the corresponding first 28 and second 29 grooves located on the surface of the removable sensor module 2.

Fig. 7 shows a back view of the modular, gyro-stabilized surveillance system 1 comprising the electronic block 5, the platform 53 and the mounted removable sensor module 2.

The rear side of the electronic block 5 is equipped with safety devices 41 , electrical connector 23 for electrical and electronically contact with the mobile carrier, switch-on controls 42, and LEDs 37 for the control of function of the surveillance system 1. Beneath the electronic block 5, the mounting-plate 6 with holes for fixation 35 for a rigid fixation of the mounting-plate 6 to the mobile carrier is provided.

Beneath the mounting-plate 6 there is the rotatable, preferably u-shaped platform-frame 7. Between the blades of the platform-frame 7 the rear side of the first 26 and second 27 bracket of the movable module holder 17 is shown.

Between the first 26 and second 27 bracket of the movable module holder 17, the removable sensor module 2 is mounted. The removable sensor module 2 is able to rotate around the first 49 and the second 50 axis; thereby the sensors inside the removable sensor module 2 could be gyro-stabilized by two axes not shown in fig. 7.

Fig. 8 shows a front view of the modular, gyro-stabilized surveillance system 1 comprising the electronic block 5, the platform 53 and the mounted removable sensor module 2. On top there is the front side of the electronic block 5. Beneath the electronic block 5 there is the mounting- plate 6 for a rigid fixation the mounting-plate 6 at the mobile carrier. Beneath the mounting-plate 6 there is the rotatable, u-shaped platform-frame 7. Between the blades of the platform-frame 7, the front side of the removable senor module 2 is shown. The front side of the removable senor module 2 is equipped with a hatch 34 with optical windows 16 for the sensors 12 located behind the windows 16. On the right side of the removable sensor module 2 the end 47 of the cylinder RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO rod 21 is arranged. The end 47 of the cylinder rod 21 is easily accessible at this location for dismounting the removable sensor module 2.

During the follwing paragraphs, the invention will now be explained focusing on how the different parts are assembled together and operate together. The removable sensor module 2 comprises a gas tight housing 4 with one or more sensors for surveillance, which are located inside the gas tight housing. On the surface of the housing 4 there are means for fixation, dismantling, electronically and electrically communications located. The sensors 12 inside the housing 4 are gyro-stabilizable by a first 49 and a second 50 axis by means of the stationary part 3 and preferred by means for gyro-stabilization inside the housing 4 by a third 43 and fourth 24 axis. Thereby, it is possible to gyro-stabilize the sensors at least by two axes.

In the removable sensor module 2 there are one or more sensors 12 located in the gas-tight housing 4. The sensors 12 could be IR, VIS, or UV-camera, laser-range-finders, microwave detectors or other physical detection systems. Electronic components 20 for the activity of the sensors 12 are connected with the sensors 12.

Due to the high sensitivity of the sensors 12 and the electronic components 20, the sensors 12 and the electronic components 20 need an inert-gas atmosphere and dust-free environment with low humidity. Therefore, sensors 12 and electronic components 20 are protected by an inert gas. The inert gas may be nitrogen, argon, or any other inert gas. The installation of the sensors 12 in the housing 4 cannot be performed in the field, but only in specially equipped workshops. Furthermore, the sensitivity of the sensors 12 demands a gas-tight housing 4 after the installation of the sensors. Inside the housing 4, the sensors 12 are protected against, dust, humidity, bacteria, fungi, which may disturb the function of the sensors 12 and electronic components 20 inside the housing 4. In the removable sensor module 2 the sensors 12 and electronic components 20 are preferably mounted on a single carriage frame 10. The carriage frame 10 may be inserted into a sensor holding frame 11. The use of the carriage frame 10 and the sensor holding frame 1 1 facilitate the installation of the sensors 12 during manufacturing of the removable sensor module 2.

It is pointed out that though some figures show an opened housing 4 of the removable sensor module 2, no opening of the housing 4 is required during mounting or dismounting of the removable sensor module 2 to or from the stationary part 3 of the modular, gyro-stabilized surveillance system 1.

The housing 4 of the removable sensor module 2 serves as a gas-tight capsule for the sensors 12. The housing 4 may comprise two covers; a front cover 9 and a back 8 cover as shown in Fig. 4, which could be combined to form the gas-tight housing 4. The closed housing 4 is gas- tight to prevent the escape of inert gas out of the housing and the infiltration of air, dust, fungi, bacteria, moisture and other disturbing substances inside the housing 4, which could interfere with the function of the sensors 12. To achieve gas-tightness, the front cover 9 and back cover 8 have means for sealing. For instance, one or more gaskets 32 could be used, which are placed between the front cover 9 and back cover 8, when the housing 4 is closed. The closing of the gas-tight housing 4 is performed by fitting the front cover 9 and the back cover 8 together and fixing the covers by closing means. Preferably, the closing means are multitude of screws RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO and threads, which are orientated at the side of front, cover 9 and back cover 8 around the gasket 32, i.e. outside the gas-tight seal. In the preferred embodiment, screws fix front cover 9 and back cover 8. Preferably, there are a multitude of pits for screws 39 located at a side of the front cover 9. The multitude of pits for screws 39 serve to countersink the screws, when front cover 9 and back cover 8 are fixed together.

In the preferred embodiment, the back cover 8 provides a sensor holding frame 1 1 with guides for the installation of the sensors 12 placed on a carriage frame 10. This facilitates the installation of the sensors 12 during manufacturing of the removable sensor module 2.

In the preferred embodiment, the sensor-holding frame 1 1 is movable by two axes, the third axis 43 and the fourth axis 24, inside the housing 4. The third 43 and the fourth 24 axes have the same orientation as the first 49 and second 50 axes of the stationary part 3.

Furthermore, inside the housing 4, a gyroscope 33 and a torque motor are located for gyro- stabilization. Thereby, it is possible to gyro-stabilize the sensors 12 by two axes. The gyro- stabilization of the sensors 12 within the housing 4 serves for the fine-tuning of the gyro- stabilization of the overall-surveillance system 1.

Outside the gas-tight sealing of the back cover 8, a cylinder rod 21 with a pullout bolt may be located. This pullout bolt may be used to facilitate the displacement of the removable sensor module 2 from the stationary part 3. By screwing the pullout bolt into the cylinder rod 21 , the bolt presses against a supporting plane 14 of the movable module holder 17 of the stationary part 3. Thereby the removable sensor module 2 is separated from the connections of the movable module holder 17 and could be easily removed.

The front cover 9 of the housing 4 is equipped with hatches 34, which have one or more optical windows 16 for the sensors 12 inside the housing 4. Furthermore, the front cover 9 is also equipped with a multitude of closing means, which are complementary to the closing means of the back cover 8. The preferred closing means are screws and threads. Front 9 and back 8 cover can be fixed together resulting in a gas-tight housing 4.

Furthermore, after fixing front 9 and back 8 cover the first end of the cylinder rod 47 with the pullout bolt ends at the surface of the front cover 9. This makes it possible that the first end 47 of the pullout bolt is easily accessible in the case of dismantling the removable sensor module 2.

The preferred overall-structure of the removable sensor module 2 is a ball, wherein ball- segments are missing. The missing ball-segments are complemented to ball after connecting the removable sensor module 2 with the movable module holder 17.

It is pointed out that the centre of gravity of the removable sensor module 2 is not identical with the geometrical centre thereof in a dismounted state. Only after mounting the removable sensor module 2, 51 , 52 to the movable module holder 17, the centre of gravity and geometrical centre of the entity consisting of the removable sensor module 2, 51 , 52 and the movable module holder 17 become identical. The identity of the centre of gravity and geometrical centre is a precondition for the gyro-stabilization of the entity consisting of the removable sensor module 2, 51 , 52 and the movable module holder 17. RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO

In the preferred embodiment, at the two opposite sides of removable sensor module 2, 51 , 52, there is a first mounting plane and a second mounting plane 30 provided. The first and second mounting plane 30 shows in the direction opposite to the front cover 9. The first or second mounting plane 30 may be shaped identical or different. In the preferred embodiment, the first and/or second mounting plane 30 means for fixation, means to facilitate mounting or dismounting, and means for electrically and electronically contacting the removable sensor module 2 with the stationary part 3 of the surveillance system 1 are provided. These means are designed and located in that way that they fit into complementary means on the movable module holder 17 of the stationary part 3, if they come into contact with the complementary means of the movable module holder 17.

The means for fixation on first and second mounting plane 30 could be fixing screws 31 , preferably self secured screws. The use of self-secured screws facilitates mounting or dismantling the modular sensor module e.g. in the field, by preventing the loss of the fixing screws 31. In the preferred embodiment not more as four fixing screws 31 are used for fixation the removable sensor module 2. Respectably, two fixing screws 31 are located on first and second mounting plane 30. The use of only four fixing screws 31 enables an easy and fast mounting or dismantling the removable sensor module 2, 51 , 52.

Furthermore, one means to facilitate the dismantling the removable sensor module 2, 51 , 52 is a pullout bolt. Preferred, the second end 53 of the cylinder rod 21 with the pullout bolt ends at the surface of first mounting plane 30. This makes it possible that by screwing first end 47 of the pull-out bolt the pull-out bolt pushes the movable module holder 17 and cuts the connections between movable module holder 17 and removable sensor module 2, 51 , 52 in the case of dismantling the removable sensor module 2, 51 , 52. Of course, this is only possible after the fixing screws 31 are opened before. Furthermore, the preferred means for electrically and electronically contact are second electrical connectors 190. One or more, preferred two second electrical connectors 190 are located on the first mounting plane 30. The second electrical connectors 190 serve as power supply and electrically and electronically control of the removable sensor module 2, 51 , 52. The second electrical connectors 190 are designed in this way that they are in optimal electrical connection with complementary shaped first electrical connectors 19 located at the movable module holder 17, when they are pressed together.

Furthermore, the means to facilitate the mounting of the removable sensor module 2, 51 , 52 are one or more, preferred two leading pins 38. The leading pins 38 are preferred located on the first mounting-plane 30. The leading pins 38 fits into corresponding holes for leading pins 36 located on the movable module holder 17. The leading pins 38 ensure a correct orientation of the removable sensor module 2, 51 , 52 during mounting of the removable sensor module 2, 51 , 52.

Furthermore, on the surface of the housing 4 there are additional means for facilitating the mounting or dismantling of the removable sensor module 2, 51 , 52. The means are one or more grooves 28, 29 for tongues 45, 46 which are located at one or both sides of the housing 4. The grooves 28, 29 are open at the backside of surface of the housing 4 and dead end at first 30 and/or a second mounting plane. The grooves 28, 29 are shaped in that way, that they exactly RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO receive tongues 45, 46, which are located at the movable module holder 17. The grooves 28, 29 make it possible, that the removable sensor module 2, 51 , 52 is still retained by the movable module holder 17 even if all other connections between the removable sensor module 2, 51 , 52 and the movable module holder 17 are opened. This facilitates mounting and dismantling of the removable sensor module 2, 51 , 52 and makes it possible that the exchange of a removable sensor module 2, 51 , 52 is performed by a single person.

Furthermore the total weight of the removable sensor module 2, 51 , 52 is less than 30kg, preferred less than 20kg. This low weight facilitates that removable sensor module 2, 51 , 52 could be handled by a single person. The first removable sensor module 2 is defined as the removable sensor module 2 that is connected with stationary part 3 of the modular, gyro-stabilized surveillance system 1.

A second removable sensor module 51 is that removable sensor module 1 that has a same composition as the first removable sensor module but is not connected with the stationary part 3. The second removable sensor module serves in the case of a failure of the first removable sensor module as an exchange removable sensor module.

The further removable sensor modules 52 are the removable sensor modules that have a different composition in comparison with the first removable sensor module. The different composition may be different sensors 12 located in the further removable sensor modules 52 in comparison to the first removable sensor module. The different sensors 12 may serve in different tasks of surveillance, e.g. IR- in place of UV-surveillance.

First, second or further removable sensor modules 2, 51 , 52 have the same means for fixation, means to facilitate mounting or dismantling, and means for electrically and electronically contacting the removable sensor module 2, 51 , 52 with the stationary part 3 on the surface. The means for fixation, means to facilitate mounting or dismantling, and means for electrically and electronically contacting are located at the same positions on the second or further removable sensor modules 51 , 52 as they are located on the surface of the first removable sensor module 2.

Furthermore the weights of first, second or further removable sensor modules 2, 51 , 52 are identical, essentially. Because of these features an exchange of removable sensor modules - that means the dismantling of first removable sensor module 2 from the stationary part 3 and the mounting of second 51 or further 52 removable sensor modules at the stationary part 3 of the surveillance system 1 - is possible in very short time, even in the field by a single person.

The stationary part 3 of the modular, gyro-stabilized surveillance system 1 comprises a platform 53 and an electronic block 5 that serves as power supply and electrically and electronically control unit for the surveillance system 1. The platform 53 comprises a mounting-plate 6, which serves for a rigid fixation of the platform 53 with the mobile carrier, b a platform-frame 7 which is connected rotatable in relation to the mounting-plate 6 by a first axis 49, and c a movable module holder 17, which is connected rotatable in relation to the platform-frame 7 by a second axis 50. RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO

The movable module holder 17 comprises a first 26 and a second 27 bracket. First 26 and a second 27 bracket are preferred physically connected on one or both ends of the brackets to form a u- or o-shape movable module holder 17. In the preferred embodiment the movable module holder 17 is u-shaped. Furthermore, the shape of the movable module holder 17 is designed that way that the entity formed by the movable module holder 17 and the removable sensor module 2, 51 , 52 is a ball like structure.

Furthermore, the centre of gravidity and the geometrical centre of the entity formed by removable sensor module 2, 51 , 52 and movable module holder 17 are identically. The identity of the centre of gravity and geometrical centre is one pre-condition for the gyro-stabilization of the entity consisting of the removable sensor module 2, 51 , 52 and the movable module holder 17.

On the surface of first 26 and/or second 27 bracket there are means for fixation, means to facilitate mounting or dismantling, and means for electrically and electronically contacting the removable sensor module 2, 51 , 52 with the stationary part 3 of the surveillance system 1. These means are designed and located in this way that they fit into complementary means on the removable sensor module 2, 51 , 52, if they come into contact with the means of the removable sensor module 2, 51 , 52.

The means for fixation on first 26 and second 27 bracket could be threads 44 for fixing screws 31 located at the movable module holder. In the preferred embodiment not more as four threads 44 are used for fixation of the removable sensor module 2, 51 , 52 at the movable module holder 17. Respectably, two threads are located on first 26 and second 27 bracket. The use of only four threads enables an easy and fast mounting or dismantling the modular sensor module 2, 51 , 52. Furthermore, one means to facilitate the dismantling the modular sensor module 2, 51 , 52 is a supporting plane 14 for a pullout bolt. Preferred the supporting plane 14 is located in the centre of the first bracket 26. When connected with the removable sensor module 2, 51 , 52 the supporting plane 14 faces the second end 53 of the cylinder rod 21 with the pullout bolt. This makes it possible that by screwing first end 47 of the pull-out bolt the pull-out bolt pushes against the supporting plane 14 of movable module holder 17 and cuts the connections between movable module holder 17 and removable sensor module 2, 51 , 52 in the case of dismantling the modular sensor module 2, 51 , 52. Of course, this is only possible after the fixing screws 31 are opened before.

Furthermore, preferred the means for electrically and electronically contact are second electrical connectors 190. One or more, preferred two, second electrical connectors 190 are located on the first bracket 26. The second electrical connectors 190 serve as power supply and electrically and electronically control of the removable sensor module 2, 51 , 52. The second electrical connectors 190 are designed in this way that they are in optimal electrical connection with complementary shaped first electrical connector 19 located at the removable sensor module 2, 51 , 52, if they are pressed together.

Furthermore, one means to facilitate the mounting of the removable sensor module 2, 51 , 52 is one or more, preferred two holes 36 for leading pins 38. The holes 36 for leading pins 38 are RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO preferred located on the first bracket 26. The holes 36 for leading pins 38 fit into corresponding leading pins 38 located on the removable sensor module 2, 51 , 52. The holes 36 for leading pins 38 ensure a correct orientation of the removable sensor module 2, 51 , 52 during mounting of the removable sensor module 2, 51 , 52. Furthermore, on the surface of the first 26 and/or second 27 bracket there are additional means for facilitating the mounting or dismantling the removable sensor module 2, 51 , 52. One means is one or more tongues 45 which are located at lower part of first 26 and/or second 27 bracket. The tongues 45 are shaped in that way, that they exactly fit into grooves 28, 29, which are located at the removable sensor module 2, 51 , 52. The tongues 45 in combination with the grooves 28, 29 make it possible, that the removable sensor module 2, 51 , 52 is still retained by the movable module holder 17 even if all other connections between the removable sensor module 2, 51 , 52 and the movable module holder 17 are opened. This facilitates the mounting and dismantling of the removable sensor module 2, 51 , 52 and makes it possible that the exchange of a removable sensor module 2, 51 , 52 is performed by a single person. The brackets 26, 27 of the movable module holder 17 are connected movable with a platform- frame 7 by a second axis 50. The second axis 50 consists of two opposite located, part-axes, wherein each part-axis connects one of the two brackets 26, 27 with the platform-frame 7. The first second crosses virtually the centre of gravidity and the geometric centre of the entity of movable module holder 17 and removable sensor module 2, 51 , 52. Furthermore, the orientation of the second axis 50 is identical with the orientation of the third axis 43 inside the removable sensor module 2, 51 , 52. Thereby a very exact gyro-stabilization of the sensors 12 by the second 50 and third 43 axis is possible. Means for gyro-stabilization of the second axis 50, e.g. gyroscopes and motors, are provided by the platform 53.

The preferred shape of the platform-frame 7 is u-shaped and the movable module holder 17 is mounted between the blades of the u-shaped platform-frame 7. Within the blades of the u- shaped platform-frame 7 the movable module holder and the removable senor module is rotatable in y-orientation.

Upside the opening of the u-opening of the platform-frame 7 the platform-frame 7 is connected movable, with a first axis 49. The first axis 49 is orientated perpendicular to the second axis 50. Furthermore, the orientation of the first axes 49 is directed to the centre of gravidity and the geometrical centre of the entity of movable module holder 17 and mounted removable sensor module. Furthermore, the stationary part 3 provides means for gyro-stabilization and electrical and electronically contact with the movable module holder 17 and the electronically block 5. Thereby a gyro-stabilization of the sensors 12 by the first 49 and second 50 axis is possible. Means for gyro-stabilization of the first 49 and second 50 axis are provided by the stationary part 2. The first axis 49 connects rotatable the platform-frame 7 with a mounting-plate 6 of the platform 53. The platform-frame 7 is able to rotate more than 360° around the first axis 49. By the combination of the gyro-stabilized first 49 and second 50 axes a gyro-stabilized surveillance by the sensors 12 in all directions is possible. The mounting-plate 6 of the platform 53 serves as rigid fixation of the platform 53 at a mobile carrier system. The mobile carrier system could be a plane, a helicopter, a ship, a car or any other vehicle. The mounting-plate 6 can be fixed by any fixations means. The fixing means RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO could be screws, rivets, clamps and so on. Preferred, the mounting-plate 6 is fixed on the outside of the surface of the mobile carrier.

A function of the electronic block 5 is to serve as power supply and control of the electric and electronic of the platform 53 and the removable sensor module 3. Therefore, the electronic block 5 is equipped with the according integrated circuits, control units, fuses and control lights. Furthermore the electronic block is equipped with means 23 for receiving electric power from the mobile carrier and means 23 for electronically communication with the mobile carrier. Furthermore the electronic block 5 is equipped with switch on controls 42, and safety devices 41 , and light diodes 37 for the control of the electric circuits inside the electronic block 5, the platform 53 and the removable sensor module 3. The electronic block 5 can be mounted above the platform 53, as well as it can be installed remotely to achieve a better trimming, e.g. a flight device.

In the following the course of an exchange of a removable sensor module 3 of the modular, gyro-stabilized surveillance system 1 is described. Following scenario is assumed: A ship as a mobile carrier has the task of surveillance of a certain sea area. The ship is equipped with the disclosed modular gyro-stabilized surveillance system 1. The surveillance system 1 is fixed at a mast. A first modular sensor module 2 is mounted at the platform 53 of the surveillance system 1. Second 51 or further 52 modular sensor modules are provided on board of the ship. In the case of a defect of the sensors 12 of the surveillance system 1 , the following method of exchange is scheduled: a) stop surveillance of the modular, gyro-stabilized surveillance system 1 , whereby the first removable sensor module 2 is orientated in this way that the grooves 28, 29 from the housing 4 are in parallel to the base in this case the deck of ship, b) one person of course it could be more than one approaches modular, gyro-stabilized surveillance system 1 , c) the person is equipped with a handheld tool, preferred a mechanical or electrical screwdriver, d) the person unscrews the four or less fixing screws 31 of the first removable sensor module 2 which connect the first removable sensor module 2 with the movable module holder 17, whereby the fixing screws 31 remain in first removable sensor module 2, e) the person screws the pull-out bolt of the first removable sensor module 2, thereby the pull-out bolt pushes against the supporting plane 14 of movable module holder 17 and cuts the connections of the first and second electrical connectors 190, 19 between movable module holder 17 and removable sensor module 2 and whereby the first removable sensor module 2 is stilled hold by the tongues 45 of the movable module holder 17 which are still inside the grooves 28, 29 of the first removable sensor module 2, f) the person pulls the first removable sensor module 2. Thereby, the tongues 45 slide within the grooves 28, 29 of the first removable sensor module 2 until the tongues 45 are out of the grooves 28, 29, now the first removable sensor module 2 loose. RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO g) the person deposits the first removable sensor module 2 this is the only moment, in which the person has to stabilize the weight of the first removable sensor module, h) the person takes a second removable sensor module 51 this is the only moment, in which the person has to stabilize the weight of the second removable sensor module, i) the person puts the grooves 28, 29 of the second removable sensor module 51 into the tongues 45 of the movable module holder 17 and pushes the second removable sensor module 51 until the first and second electrical connectors 19, 190 of movable module holder 17 and second removable sensor module 51 come in first - not necessary conductive - contract, j) the person fixes the second removable sensor module 51 at the stationary part 2 of the surveillance system 1 by screwing the four fixing screws 31 which are provided by the second removable sensor module 51 in the threads for fixing screws 46 of the movable module holder 17, whereby the first and second electrical connectors 19, 190 of movable module holder 17 and second removable sensor module 51 come in second, now conductive contract, k) start the surveillance of the modular, gyro-stabilized surveillance system 1.

The steps a-k may be performed within 15min, preferably within 10min. The steps b-j may be performed within 15min, preferably within 10min. The steps a-k or b-j may be performed on the free field or on the sea under application conditions. The steps a-k or b-j may be performed without the need of a special workshop. The steps b-j may be performed without especially skilled persons. A single person may perform the steps b-j, only. The steps b-j may be performed without the need of electrically power

In short, the method for exchanging the removable sensor module of the modular surveillance system 1 comprises the following steps: providing an inventive modular surveillance system 1 fixed to a mobile carrier, stopping surveillance, dismounting a first removable sensor module 2 from the movable module holder 17 without opening the gas-tight housing 4 of the removable sensor module 2 while the stationary part 3 remains fixed on the mobile carrier, mounting a second removable sensor module 2 gas-tightly to the movable module holder 17, and starting surveillance. The electrical connection between the sensor module 2 and the movable module holder 17 is provided by a pressing force establish during mounting of the sensor module 2 to the module holder 17 exerted on respective electrical connections on the surfaces of the sensor module 2 and the module holder 17, respectively.

The dismounting step comprises removing the means for fixation, holding together the sensor module 2 and the module holder 17 by tongues 45 of the module holder 17 provided inside grooves 28, 29 of the sensor module 2; and exerting a pulling force on the sensor module 2 to dismount the sensor module 2 from the module holder 17.

The described embodiments are provided as examples only and do not limit the scope of invention provided by the claims. RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO

List of reference signs

1 modular, gyro-stabilized surveillance system (MGS)

2 removable sensor module (RSM)

3 stationary part (SP)

4 housing (HO)

5 electronic block (EB)

6 mounting-plate (MPt)

7 platform-frame (PF)

8 back cover (BC)

9 front cover (FC)

10 carriage frame (CF)

1 1 sensor holding frame (SHF)

12 sensors (SE)

14 supporting plane (SPP)

15 torque motor (TM)

16 optical windows (Wl)

17 movable module holder (MMH)

19 first electrical connectors (fEC)

20 electronic components (CO)

21 cylinder rod (CR)

23 electrical connectors (EC)

24 fourth axis (FAX)

26 first bracket (fB)

27 second bracket (sB)

28 first and second groove (fGO)

30 first mounting plane (fMP)

31 fixing screws (FSC)

32 gasket (GA)

33 gyroscope (GY)

34 hatch (HA)

35 holes for fixation (HF)

36 holes (HLP) for leading pins

37 diodes (LD)

38 leading pins (LP)

39 pits (PCS)

41 safety devices (SD)

42 switch on controls (SOC)

43 third axis (TAX)

44 threads for closing screws (TCS)

45 first and a second tongues (TO)

46 Threads for fixing screws

47 End of cylinder rod RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO

48 yoke

49 first axis

51 second removable senor module

52 further removable senor modules

53 platform

190 second electrical connectors

Claims

RECON TECHNOLOGY EUROPE GMBH 26.05.2009P546308WO-HH/LOCLAIMS

1. Modular, gyro-stabilized surveillance system (1 ), comprising: a removable sensor module (2) incorporating at least one gyro-stabilized surveillance sensor (12); and a stationary part (3) comprising means for mounting the surveillance system (1 ) to a carrier, an electronic block (5) for controlling the surveillance system (1 ), means for gyro- stabilization by a first axis (49) and a second axis (50) and a movable sensor module holder (17) for holding the sensor module (2) being movable around the first and second axis (49, 50), characterized in that the removable sensor module (2) is provided with a housing (4) having a gas-tight seal and incorporating the at least one sensor (12), wherein the removable sensor module (2) is adapted to be mounted and dismounted from the stationary part (3) in a gas-tight state, means for fixation of the removable sensor module (2) to the stationary part (3) are provided on the surface of the removable sensor module (2) outside the gas-tight seal and matching means for fixation are provided on the surface of the sensor module holder (17), electrical connectors (19) are provided on the surface of the removable sensor module (2) outside the gas-tight seal and matching electrical connectors (190) are provided on the surface of the sensor module holder (17).

2. Modular surveillance system (1 ) of claim 1 , wherein the at least one sensor (12) of the removable sensor module (2) is gyro-stabilized by said first axis (49) and said second axis (50) through the stationary part (3) and/or is gyro-stabilized by a third axis (43) and fourth axis (24) through further means for gyro-stabilization provided inside said housing (4).

3. Modular surveillance system (1 ) of claim 2, wherein the third (43) and fourth (24) axis have the same orientation as the first (49) and second (50) axis. RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO

4. Modular surveillance system (1 ) of one of the preceding claims, wherein means to facilitate mounting of the removable sensor modules (2) to the movable module holder (17) are located on the surface of the movable module holder (17) and the removable sensor module (2) in a corresponding location.

5. Modular surveillance system (1 ) of claim 4, wherein the means to facilitate mounting are provided outside a gas-tight sealing of the housing (4) and comprise: one or more leading pins (38) on the surface of the sensor module (2) with corresponding holes (36) on the surface of the module holder (17); and/or one or more grooves (27, 28) on the surface of the sensor module (2) for respective tongues (45) formed on the surface of the module holder (17); and/or an end of a cylinder rod (47) on the surface of the sensor module (2) for receiving a pull-out bolt (40) and a corresponding supporting plane (14) formed on the surface of the module holder (17).

6. Modular surveillance system (1 ) of one of the preceding claims, wherein the means for fixation located on the surface of the housing (4) of the removable sensor module (2) are fixing screws (31 ) or self secured fixing screws (31 ) and the matching means for fixation on the surface of the module holder (17) are corresponding threads (46).

7. Modular surveillance system (1 ) of one of the preceding claims, wherein the movable module holder (17) has the shape of a yoke.

8. Modular surveillance system (1 ) of one of the preceding claims, wherein the movable module holder (17) comprises at least a first (26) and a second bracket (27), which are connected movable with a platform-frame (7).

9. Modular surveillance system (1 ) of at least one of the claims 5, 6 or 8, wherein the supporting plane (14) and/or the hole for leading pins (36) and/or the electrical connectors (190) and/or the threads for fixing screws (46) are located on at least one of the brackets (26, 27) of the movable module holder (17). RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO

10. Modular surveillance system (1 ) of one preceding claims, wherein the centre of gravidity of the entity consisting of the removable sensor modules (2) mounted to the movable module holder (17) is located on one of the first axis (49), second axis (50), third axis (43) or fourth axis (24) and/or wherein the centre of gravidity of the entity consisting of the removable sensor module (2) mounted to the movable module holder (17) and the geometrical centre of the entity are identical.

1 1. Modular surveillance system (1 ), wherein the at least one sensor (12) is a IR, VIS, UV- camera, a laser range finder, microwave detector, and/or positioning sensors provided in the gas-tight housing (4).

12. Modular surveillance system (1 ), wherein the housing comprises a front cover (9) and a back cover (8) each having means for sealing (32) the housing gas-tightly.

13. Method for exchanging the removable sensor module (2) of the modular surveillance system (1 ) of claims 1 - 12, comprising the following steps: providing modular surveillance system (1 ) of claims 1 - 12 fixed to a mobile carrier, stopping surveillance, dismounting a first removable sensor module (2) from the movable module holder (17) without opening the gas-tight housing (4) of the removable sensor module (2) while the stationary part (3) remains fixed on the mobile carrier, mounting a second removable sensor module (2) gas-tightly to the movable module holder (17), starting surveillance.

14. Method of claim 13, wherein the electrical connection between the sensor module (2) and the movable module holder (17) is provided by a pressing force establish during mounting of the sensor module (2) to the module holder (17) exerted on respective electrical connections on the surfaces of the sensor module (2) and the module holder (17), respectively. RECON TECHNOLOGY EUROPE GMBH 26.05.2009 P546308WO-HH/LO

15. Method of claim 13 or 14, wherein the dismounting step comprises: removing the means for fixation; holding together the sensor module (2) and the module holder (17) by tongues (45) of the module holder (17) provided inside grooves (28, 29) of the sensor module (2); and exerting a pulling force on the sensor module (2) to dismount the sensor module (2) from the module holder (17).

16. A modular gyro-stabilized surveillance system kit, comprising a modular gyro-stabilized surveillance system (1 ) of claims 1-12, and at least one additional removable sensor module (51 , 52) incorporating the same or different surveillance sensors for replacing the removable sensor module (2) of the gyro- stabilized surveillance system (1 ).