GB2551391A - An apparatus and system for sensing movement - Google Patents

Abstract

An apparatus for detecting a disturbance or movement along, for example, a boundary or perimeter fence. The apparatus comprises a cable assembly 10 having at least two longitudinal sections (100a, 100b) and at least two electrical paths (101, 102), each electrical path being divided into at least two sections (101a, 101b, 102a, 102b). The first section of the electrical paths (101a, 102a) is within the first longitudinal section 100a and the (at least) second section of the electrical paths (101b, 102b) lies within (at least) the second longitudinal section 100b. The first longitudinal section 100a may further comprise an elongate magnetic member.The varying electrical path sections are either movable or fixed within a particular longitudinal section, such that there is a unique combination of movable and fixed sections for each longitudinal section. This allows a processor or analyser unit to determine where along the apparatus a disturbance has occurred. The apparatus may comprise (2N 1) longitudinal sections, where N is the number of electrical paths.

Description

AN APPARATUS AND SYSTEM FOR SENSING MOVEMENT TEOHNOLOGICAL FIELD

Examples of the present disclosure relate to on apparatus and system for sensing movement. Some examples, though without prejudice to the foregoing, relate to an apparatus and system for use in a security device/system for sensing mechanical disturbances to a boundary/perimeter which may be indicative of an intruder or other interference.

BACKGROUND

Sensing devices for sensing movement/vibrotions ore well known. Certain such devices may comprise a cable type movement/vibration sensitive sensor whose principle of operation involves providing the cable with a flexible internal wire that can move freely within a magnetic field within the cable such that, responsive to an applied movement/force/vibration, the wire moves/vibrates within the magnetic field and a current is induced therein. The induced current may be detected and used to produce an alert signal. Such cable type movement/vibration sensors are not always optimal and it con be difficult to determine where along the length of the cable the movement/force/vibration occurred.

The listing or discussion of any prior-published document or any background in this specification should not necessarily be taken as an acknowledgement that the document or background is part of the state of the art oris common general knowledge. One or more aspects/examples of the present disclosure may or may not address one or more of the background issues.

BRIEF SUMMARY

According to at least some but not necessarily all examples of the disclosure there is provided an apparatus comprising: α cable assembly having a first longitudinal section and at least a second longitudinal section, the cable assembly comprising: a first electrical path extending along the first and at least second longitudinal sections, the first electrical path having a first section within the first longitudinal section and at least a second section within the at least second longitudinal section: at least a second electrical path extending along the first and at least second longitudinal sections, the second electrical path having a first section within the first longitudinal section and at least a second section within the at least second longitudinal section; and wherein: the first section of the first electrical path is configured such that it is moveable within the first longitudinal section, the first section of the second electrical path is configured such that it is fixed within the first longitudinal section, and the second section of the second electrical path is configured such that it is moveable within the second longitudinal section.

According to at least some but not necessarily all examples of the disclosure there is provided a module or seourity system comprising the above apparatus

According to at least some but not necessarily all examples of the disclosure there is provided a method of manufacturing the above apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of various examples of the present disclosure that are useful for understanding the detailed description and certain embodiments of the invention, reference will now be made by way of example only to the accompanying drawings in which:

Figure lA schematically illustrates a side-on cut through view of an apparatus according to the present disclosure;

Figures IB and 1C schematically illustrate cross sectional views of the apparatus of Figure 1;

Figures 2A and 2B schematically illustrates side-on cut through views of further apparatuses according to the present disclosure;

Figure 3 schematically illustrates a system incorporating a yet further apparatus according to the present disclosure;

Figures 4 and 5 illustrate cross sectional views of sections 1 and 15 of the apparatus of Figure 3;

Figure 6 illustrates a cross sectional view of a yet further apparatus according to the present disclosure;

Figure 7 illustrates a cross sectional view of a yet further apparatus according to the present disclosure;

Figure 8 schematically illustrates a system incorporating a yet further apparatus according to the present disclosure; and Figure 9 schematically illustrates an overall system according to the present disclosure.

Similar reference numerals are used in the Figures to designate similar features. For clarity, all reference numerals are not necessarily displayed in all figures.

DETAILED DESCRIPTION

The Figures schematically illustrate an apparatus 10 comprising: a cable assembly 100 having a first longitudinal section 100a and at least a second longitudinal section 100b, the cable assembly 100 comprising: a first electrical path 101 extending along the first and at least second longitudinal sections, the first electrical path 101 having a first section 101a within the first longitudinal section 100a and at least a second section 101 b within the at least second longitudinal section 100b; at least a second electrical path 102 extending along the first and at least second longitudinal sections, the second electrical path 102 having a first section 102a within the first longitudinal section 100a and at least a second section 102b within the at least second longitudinal section 100b; and wherein: the first section 101 a of the first electrical path 101 is configured such that it is moveable within the first longitudinal section lOOo, the first section 102a of the second electrical path 102 is configured such that it is fixed within the first longitudinal section 100a, and the second section 102b of the second electrical path 102 is configured such that it is moveable within the second longitudinal section 100b.

For the purposes of illustration and not limitation, in some examples, the apparatus 10 may be configured for use as a sensor or for use in a sensing system for sensing mechanical disturbances, such as an applied force, impulse, movement or vibration. In overview, in such examples, the apparatus may be further provided with one or more transducers. Such transducers may be, for exampie, an arrangement of one or more magnetic members that create one or more magnetic fields within which a moveable conductor/ section of an electrical path is provided. In the event of any mechanical disturbance being applied to the apparatus which is sufficient to cause a response of the transducer, e.g. a movement of the moveable section, this gives rise to a voltage/current being generated within the moveable section (i.e. as a result of its movement through the magnetic field and its crossing of magnetic field lines). The induced voltage/current signal may propagate through the electrical path for detection and processing and may be used to trigger an alert signal, which may be indicative of a mechanical disturbance to the apparatus.

Advantageously, in certain embodiments of the invention, since each longitudinal section of the apparatus comprises a unique combination of moveable and fixed sections of electrical paths (i.e. a unique combination of transducing/responsive sections and non-transducing/non-responsive sections), the signals generated from the electrical paths may be processed to provide a unique signature depending upon which particular longitudinal section α mechanical disturbance event occurred which gave rise to the movement of a particular moveable section of a particular electrical path within a particular longitudinal section and thus generating a signal for that particular electrical path. By processing the received signals from each of the electrical paths, a unique signature/fingerprint is provided that can be used to identify which particular longitudinal section of the apparatus a mechanical disturbance event was detected. Accordingly, such embodiments not only enable the detection of a mechanical disturbance but also provide an indication as to a section of the apparatus at which the disturbance took place.

In certain examples of use of the apparatus, the apparatus is fixedly attached to a boundary/security perimeter structure, e.g. fence or wall, such that the any mechanical disturbance (e.g. due to attempted climbing, tampering, intrusion or other interference) that causes a vibration of the security perimeter structure would cause a corresponding vibration of the apparatus, in particular a localised vibration of the longitudinal section of the apparatus that is proximal to location of the interference event. Advantageously, certain embodiments may not require any electronics or active equipment to be provided out in the field.

Figure 1A schematically illustrates a side-on cut through view of an apparatus 10. Figures IB and 1C schematically illustrate cross sectional views of the apparatus at longitudinal sections 100a and 100b along the lines A-A and B-B shown in Figure 1 A.

The apparatus 10 comprises a cable assembly 100. The cable assembly 100 may be a cable-like structure, i.e. a longitudinal and elongate structure, which itself comprises a first electrical path 101 and a second electrical path 102. The electrical paths may be a communication pathway via which one or more signals may be conveyed. Each electrical path may comprise one or more wires or other electrical conductors via which an electrical signal may be conveyed therethrough. The cable assembly 100 may additionally comprise one or more core members 110 within which the first and at least second electrical paths 101, 102 are provided/embedded. The cable assembly 100 may have two or more longitudinal sections/zones/regions 100a and 100b. Each of the first and at least second electrical paths 101 and 102 extend along the two or more longitudinal sections 100a and 100b. Each electrical path has a section located within a longitudinal section of fhe cable assembly 100. For example the first electrical path 101 has sections 101a and 101 b that are respectively located within longitudinal sections 100a, 100b of the cable assembly 100.

The sections of an elecfrical pafh are configured fo be eifher fixed, e.g. 101 b, or freely moveable, e.g. 101a. A freely moveable secfion 101a may comprise a secfion of an elecfrical conducfor fhaf is loosely confained/housed wifhin fhe apparafus such fhaf is if relafively freely moveable fherein, i.e. as illusfrafed in fhe doffed represenfafions of fhe secfion and by the double headed arrows 101a’. Upon an application of a mechanical disfurbance, force, impulse or movement 104 of o longitudinal section 100a, this would give rise to a relative movement of the flexible section 101a within and relative to the longitudinal section 100a. One or more sections 102a of an electrical path 102 are also configured so as to be fixed relative to their respective longitudinal section 100a such that upon application of a mechanical disturbance, force, impulse or movement 104 of the longitudinal section 100a of the cable assembly 100, the section 102a of the electrical path 102 remains fixed/stationary within and relative to the longitudinal section 100a such that the relative position of the fixed section 102a within the longitudinal section 100a does not alter upon such an application of a mechanical disturbance.

As shown in Figures lA-lC, in the first longitudinal section 100a, there is provided one section of an electrical path which is freely moveable (namely the first section 101a of the first electrical path 101) and another section of an electrical path which is fixed (namely the first section 102a of fhe second elecfrical pafh 102). By confrasf, in fhe ofher longifudinal secfion 100b, fhe second section 101b of the first electrical path 101 is a fixed section and the second section 102b of the second electrical path 102 is a freely moveable section. Accordingly, the distribution of freely moveable and fixed sections of each electrical path within a longitudinal section of the cable assembly 100 differs between each longitudinal section.

As shown in Figure IB, the first longitudinal section 101a comprises a first elongate hollow channel 106a defining a first elongate void space within which the first section 101a of the first electrical path 101 is able to freely/readily move. Likewise, as shown in Figure 1C, in the second longitudinal section 100b, a second elongate hollow channel 106b is provided that defines a second elongate void space within which the second section 102b of the second electrical path 102 is able to freely move. For the fixed portions of the electrical paths, either such a hollow channel may not be provided or the channel may be filled such that it is not hollow nor provides any empty/void space permitting movement. For example, the fixed section of electrical path may be clad in a material that fills the channel so that no relative movement of the section of the electrical path is permitted. Yet further alternatively, the fixed section of the electrical path may comprise one or more wires/strands/cables that are greater in diameter and/or more rigid than a section of electrical path used in a moveable section.

In certain examples, each longitudinal section has a different arrangement (i.e. different combination and different permutation) of freely moveable and fixed sections of electrical paths. The distribution of such freely moveable sections (referred to as “floppy wires” or live wires that are responsive to movement) and fixed sections (referred to as “fixed” wires” or dead wires that are not responsive to movement) can be represented in the below table:

It is to be appreciated that the Figures are not necessarily to scale. Certain features and views of the Figures may be shown schematically or exaggerated in scale in the interest of clarity and conciseness. The dimensions of some elements in the Figures may be exaggerated relative to other elements to aid explication. For example, in some examples of the apparatus, the longitudinal dimensions of each longitudinal section may be of the order of: metres, lO's of metres, lOO's of metres (such that the overall cable assembly may be of the order of kilometres long); whereas the transverse dimensions/diameter may be of the order of millimetres or centimetres.

The provision of a freely moveable section of an electrical path within a longitudinal section may be provided by loosely mounting or loosely housing the section of the electrical path within the longitudinal section of the cable assembly. Such a loosely mounted/housed section may enable the section to be able to move freely/readily, for example in response to an applied mechanical disturbance, within and relative to its respective longitudinal section, as well as any other components within the cable assembly. In some examples, the longitudinal section may comprise a magnetic member such that the moveable section of the electrical path may cross through magnetic field lines of a magnetic field, giving rise to the generation of an induced EMF/induced current which may be detected. The moveable section of an electrical path may be moveable in a transverse/lateral/radial direction or a direction perpendicular to the longitudinal direction of the cable assembly.

The apparatus may be configured to generate one or more signals responsive to one or more forces applied to one or more of the longitudinal sections. The apparatus may be provided as part of a system, for example a perimeter security system, that may additionally include means for processing signals fronn the apparatus in order to generate an output, such as an alert signal.

Figures 2A and 2B schematically illustrate side-on cut-through views of further apparatuses according to the present disclosure.

The apparatus 20 of figure 2A is broadly similar to the apparatus 10 of Figure lA with the addition of a further/third longitudinal section 200c. Furthermore, within each of the longitudinal sections 200a, 200b, 200c, a magnetic member 210a, 210b, 210c, is provided. Whilst Figure 2A shows a plurality of discrete magnetic members located in each longitudinal section, it is to be appreciated that other arrangements and configurations of magnetic members may be provided, not least for example one or more elongate magnetic members that extend along each of the longitudinal sections.

In the apparatus 20 of Figure 2A, the second section 201 b of the first electrical path 201 is configured such that it is fixed within and respect to the second longitudinal section 200b. By contrast, in the apparatus 20’ in Figure 2B, the second section 201 b’ of the first electrical path 201 is configured such that it is moveable within the second longitudinal section 200b.

In the apparatus 20 of Figure 2A, the third longitudinal section 200c comprises two freely moveable secfions: 201c, 202c of the first and second electrical paths. Significantly, in each longitudinal section 200a, 200b, 200c of the apparatus 20, there is a different combination of fixed and freely moveable sections of the electrical paths within each longitudinal section.

By analysing the signals that are generated in each of the electrical paths upon a mechanical disturbance, it is possible to identify a location/zone as to where a mechanical disturbance has taken place. For example if a signal is only detecfed from fhe first electrical path 201 and no signal is detected from the second electrical path, it can be deduced that a mechanical disturbance has been applied in the first longitudinal section 200a. If a signal is only detected in the second electrical path and no signal is detected from the first electrical path, it can be determined that a mechanical disturbance has occurred within the second longitudinal section 200b. Finally, if a signal is detected in both the first and second electrical paths, it can be determined that a mechanical disturbance has occurred in the third longitudinal section 200c.

In the apparatus 20' of Figure 2B, the second longitudinal section 200b of cable assembly 200' comprises two freely moveable sections: 201 b’ and 202b of the first and second electrical paths. Significantly, in each longitudinal section 200a, 200b, 200c of the apparatus 20', there is a different combination of fixed and freely moveable sections of the electrical paths within each longitudinal section. It is to be noted that, in effect, apparatus 20' of Figure 2B corresponds to the apparatus 20 of Figure 2A but with the arrangement of sections of the electrical paths in longitudinal sections 200b, 200c swapped around.

Figures 2A and 2B show two permutations of arrangements of moveable and fixed sections of electrical paths within each longitudinal section of a cable assembly of an apparatus. Flowever, it is appreciated that various other combinations and permutations of moveable and fixed sections may be provided. By providing each longitudinal section with a unique arrangement of moveable and fixed sections of electrical paths, it is be possible to uniquely determine a particular longitudinal section within which a mechanical disturbance has occurred.

For a cable assembly comprising n electrical paths, it is possible to divide the cable assembly into 2'^ -1 sections within which a mechanical disturbance can be uniquely identified. Thus, for the example of Figures 2A and 2B where two electrical paths are provided, 2^-1 = 3 sections may be uniquely identifiable. It is to be appreciated that any number of electrical paths may additionally be provided. For example, where four electrical paths are provided, this would give rise to the ability to distinguish between 2^-1 = 15 uniquely identifiable sections.

The examples of apparatuses described thus far have predominately focused on apparafuses and cable assemblies having fwo elecfrical paths. However, it is to be appreciated that, in other examples, a plurality of electrical paths in excess of fwo, each extending along a plurality of longitudinal sections may be provided, wherein each electrical path comprises a plurality of sections that are either moveable or fixed within a particular longitudinal section. Such an apparatus may be configured such fhaf, for each longitudinal section, there is a unique combination of moveable and fixed sections of the plurality of elecfrical paths.

In certain examples of an apparatus, the cable assembly may comprise 2'^-l longitudinal sections and the cable assembly may comprise n electrical paths, each of which extend along the 2'^-l longitudinal sections. Each of the electrical paths may themselves comprise a corresponding 2'^-l sections, and each of such sections of each electrical path are either moveable or fixed within their respective longitudinal section. The apparatus may be configured such that, for each longitudinal section, there is a unique combination of moveable and fixed sections of the n electrical paths. Such an apparatus may give rise to location resolution of 2'^--l:l. For example where four electrical paths are used, a 15:1 resolution may be provided, such that if a hundred metre length of cable assembly were to be provided, the location of a mechanical disturbance could be identified down to + or - 6.6m. If eighf electrical pathways were to be used, a resolution of 255:1 could be provided. 100km of such a cable assembly would enable a determination of a location of a mechanical disturbance of + or-3.92m.

Figure 3 schematically illustrates a cable assembly 300 (referred to hereinafter as a “coded sensor cable") having four electrical pathways, shown as Wires 1 - 4: 301, 302, 303 and 304. The cable is partitioned into 15 sections. Each section of the coded sensor cable has its own unique combination of moveable sections of an electrical pathway (referred to hereinafter as “floppy wire") and fixed sections of electrical pathways (referred to hereinafter as “fixed wire"). It is to be appreciated that each section of the cable can be physically of any practical length, i.e. tens of metres, hundreds of metres of kilometre length. Each of the electrical pathways may be connected to an end of line (E.O.L.) module which is in turn connected to a common return path via a strainer wire 305. The strainer wire 305 may not only provide a common return path for electrical signals created in each of the electrical pathways, but may also advantageously provide mechanical rigidity to the coded sensor cable. The provision of an end of line module may provide an indication as to any tampering of the cable assembly 300, such as a severing or cutting of any of the electrical pathways and provide an indication as to whether or not there is an open circuit.

At a point of a mechanical disturbance, such as an attack on the cable or interference with the same, anywhere along the length of the cable, only the floppy wires in that section will respond to the vibrations created thereby.

Each electrical pathway is provided with its own analyser. Each analyser is connected to its respective electrical pathway and the common return path strainer wire 305. The analysers may process and filter the signals received and may generate an output alarm signal only if fheir associafed elecfrical pathway has generated a signal, i.e. if their associated electrical pathway has a vibrating floppy wire. Depending on fhe combination of output alarm signals from the analysers, a determination can be made as to which section the mechanical disturbance occurred. By taking the outputs of the analysers into an annunciator module, such as a “GeoVision” annunciator unit, the outputs can be decoded and the attacked section identified. See for example the following table:

Table 1

The binary coded table above may be logically increased if more than four wires ore used. Alternative coding may be used, not least for example the Gray code (where only one state change takes place between the sections) os shown in the below table:

Table 2

Figure 4 illustrates a cross-sectional view of section 1 of the cable 300 of Figure 3. Section 1, 300a, af the cable 300 comprises four electrical paths 301-304 and a centrally dispased strainer wire 305 with all five wires aligned along a diameter of the circular crass sectionally shaped cable 300. The core of the cable comprises two elongate magnetic members 310a whase magnetic pales are aligned such that a magnetic field is prcvided that passes thraugh each cf the electrical paths. In section 1 shown in Figure 4, the sequence of floppy/fixed wires is as fallaws: a floppy wire, a fixed wire, a fixed wire and a fixed wire.

Figure 5 shows section 15 300o of the cable 300 which has the following sequence of floppy/fixed wires: floppy, floppy, floppy and floppy.

In section 1 shown in Figure 4, only electrical path 301/wire 1 would generate an electrical signal, i.e. an induced EMF/current signal, upon a mechanical disturbance being made at section 1. If a mechanical disturbance were made at section 2, then only the electrical path 302/wire 2 would generate a signal. A mechanical disturbance in section 3 would cause the generation of a signal at electrical paths 301 and 302/wires 1 and 2, and so on up to section 15 wherein all faur wires would respond to a mechanical disturbance made ta section 15.

For each of the electrical paths 301-304, a tubing 311 is provided. For ‘floppy' sections of the electrical pathway, an electrical conductor may be provided within the tubing in such sections that has a cross-sectional profile which is less than the cross- sectional profile of the tubing so that the section of wire is able to readily/freely move within the remaining hollow void space of the tubing. By contrast, for sections of the electrical pathways that ore “fixed wires” i.e. non-“floppy wires”, the cross-sectional profile/dimensions of such fixed wires may substantially correspond to the cross-sectional profile/dimensions of the tubing such that the wires are securely and fixedly contained within the tubing and there is no room for the wires to move about within the tubing.

Figure 6 illustrates a cross-sectional view of a yet further apparatus according to the present disclosure. The cross-sectional view of the cable 600 shows a “section 1” section of the coble comprising, in order: a floppy wire 601 o, a fixed wire 602a, a fixed wire 603a and a fixed wire 604a. Also a strainer wire 605 is provided between the second and third wires. Elongate magnetic members 610a are provided each having a substantially semi-circular cross-section, and a mating surface that is been profiled so as to receive the various wires 601α-604α and 605 as well os tubing/cladding for the same. Such tubing may be made from any suitable material, not least for example high-density polyethylene (HDPE). The elongate and profiled magnefic members 610a may be made from a magnefic maferial which is exfruded into the desired profile shape which is subsequenfly magnefised so as fo give a desired location and positioning of magnefic poles so as fo give rise fo a flux density in the vicinity of fhe fixed and floppy wires fhat may enable movement of the floppy wires fo give rise fo a defecfable electrical signal due to induced EMF/current.

The coble assembly may be provided with means for elecfromagnefically screening the interior of fhe cable assembly, for example by being clad in a screen aluminium foil 620. This screening layer may fhen ifself be clad in an outer protective coating 621, which may be of any a suifable maferial, not least for example a polyefhylene jackef. Furfher addifional profecfive layers (not shown) could also be provided, such as to provide additional physical protection, e.g. tamper-proof/cutting resistance, by the provision of additional physical protection layers, such as flexi armoured cabling. Such an additional boundary could also help enhance the electrical signal that is induced, for example by facilitating floppy wires to continue to vibrate within armoured cabling.

It is to be appreciated that the above-described apparatus may be manufactured in any suitable manner. A single long unitary cable comprising the various sequences of sections of fixed and flappy wires may be produced having secfians af a fixed length. Alternatively, it may be desirable to manufacture lengths of each section separately and cut them to a desired length, either on site or in a factory, and then electrically cannect each cf the cable sectians ta farm fhe overall cable assembly.

The langifudinal secfians af the cable assembly are arranged together in series. In some examples the sections are directly coupled together, i.e. integrally farmed in a unifary length of cable assembly comprising the plurality af secfians. In afher examples, the sections are indirectly coupled together, e.g. via an electrical connection box, such that the cable assembly comprises a plurality of sections of cabling that are connected together via an interconnection device. In such examples, the apparatus may be pravided as a module. As used here ‘module’ refers to a unit or apparatus that excludes certain parts/components that would be added by an end manufacturer or a user. For example the apparatus/cable assembly may be provided in a modular form, namely individual sections of cable, that are subsequently connected together, e.g. as discussed below and with reference to Figure 8.

Figure 7 illustrates a cross-sectional cut-through of a cable and shows various positions within the cable, namely position 1 to position 4 where appropriate wires (i.e. either fixed wires or floppy wires) may be placed to create a particular section of cable. To assist in the manufacture and assembly of the various cable sections and the cladding assembly, colour coding may be used for example as shown in the table below:

Table 3

Where white = a floppy wire encased in a white jacket, red = fixed wire encased in red jacket, orange = a fixed wire encased in an orange jacket and yellow = a fixed wire encased in a yellow jacket.

In certain examples of the invention, the overall diameter of the cable assembly may be of the order of several millimetres to of the order of a centimetre whilst the length of the cable assembly may be of the order of tens, hundreds and thousands of metres.

Many other shapes and geometries for the various above-described components, cable assemblies and apparatuses can be envisaged. Likewise, many alternative materials, dimensions and relative dimensions could be chosen.

Figure 8 schematically illustrates a yet further apparatus 80 according to the present disclosure. Here the apparatus 80 and cable assembly 800 comprise a plurality of cable sections and a plurality of electrical junction boxes 801, each located at intersections between the sections for electrically connecting the sections, and in particular electrically connecting the respective electrical pathways of each section to one another. For a cable assembly comprising 4 paths having 15 sections, 14 junction boxes would be required. Also, a strainer wire may be provided and electrically connected between each junction box for providing a return path (not shown in Figure 8). Each electrical pathway is provided with an analyser to analyse any signals generated within the electrical pathway.

For applications where having a cable assembly with 15 sections is not sufficient (i.e. the ability to determine a mechanical disturbance applied to any particular one of 15 sections of the cable assembly is not sufficient), as discussed above, additional electrical pathways could be provided for the cable. For example, where 8 electrical pathways are provided, up to 255 sections could be uniquely identifiable. Alternatively, instead of providing an 8 electrical pathway cable assembly, two 4 electrical pathway cables could be provided, along with further analysing units for the same. The outputs from a total of 8 analyser units may be duly decoded for identifying a particular section where a mechanical disturbance is applied.

Figure 9 illustrates an overall system block diagram. The system 90 comprises a cable assembly 900 comprising a plurality of sections each with a particular combination of moveable and fixed wires. At the end of the cable, an end of line module is provided. Signals from the various electrical paths of the cable assembly are analysed in an analyser unit 920. Such analyser units may filter out “erroneous" or false signals, for example signals having a particular signature/frequency that may be indicative of vibrations due to wind or an earthquake. Based on the characteristics of the received signals (not least amplitude, frequency, duration, pulse shape ...), it may be possible to associate a type movement event to a particular profile/signature of the detected signals. The size and frequency of the electrical signal generated by a floppy wire i.e. fhe induced volfage/current of the same, will be dependent, not least, upon the strength of fhe magnetic field in the vicinity of the moveable section of the electrical path but also upon the size and frequency of fhe mechanical disturbance, for example, how violently the section of the cable assembly is shaken. For example, where the cable is fixedly affached fo a fence, it may be possible to determine that the received signals are indicative of the type of signals one would expecf for vibrations caused by a person climbing over a fence. Alternatively, the signals may have a characteristic that is indicative of a user attempfing fo cut the cable, i.e. a particular signal profile that is received immediately prior to the signal being lost. The analysers used in the system may be an Eliminator unit as produced by Geoquip Worldwide. Signals output from fhe analyser unif 920 may be provided fo a decoder unit 930 for determining in which section of the cable assembly a mechanical disturbance has been detected. An output from the decoder unit 930 may then be presented to an alerting/annunciating unit 940 which may be based on Geoquip Worldwide’s “GeoVision" system. Internet protocol (IP) communication from the analysing unit 920 and/or the decoder unit 930 to the annunciating unit 940 may be used for indicating which sections, sectors or zones has created the alarm for example based on the mapping added in either of table 1 or table 2.

Examples of the apparatus may be used in a wide range of applications in order to detect mechanical disturbances applied to sections of the cable assembly. For example, the cable assembly may be run out along a boundary such as a fence, gate, wall or other structure and securely attached thereto in order to detect any mechanical disturbances of the boundary, such mechanical disturbances which may be indicative of an intruder or other interference. Thus, examples of the present application may be used in security systems for providing both an alert to interference/attack as well as provide an indication as to a location of the interference. Such an alert may be used, for example, so as to direct security cameras towards the identified location of an attack. Since the location of the interference/tampering may be identified to a particular degree of accuracy, the security camera may be able to more accurately focus and zoom into a particularly identified area or zone such that an enhanced image of the area/zone under attach may be recorded.

Features described in the preceding description may be used in combinations other than the combinations explicitly described. Although functions have been described with reference to certain features, those functions may be performable by other features whether described or not. Although features have been described with reference to certain examples, those features may also be present in other examples whether described or not. Although various examples of the present disclosure have been described in the preceding paragraphs, it should be appreciated that modifications to the examples given can be made. For instance, whist various of the examples refer to the use of a floppy wire within a magnetic field to generate an electrical response to a mechanical disturbance, other transducing means may be implemented that generate an electrical signal in response to mechanical disturbance, such a signal being then being conveyed along the electrical pathway associated with the transducing means for subsequent detection and processing by detector and analyser units.

The term ‘comprise’ is used in this document with an inclusive not an exclusive meaning. That is any reference to X comprising Y indicates that X may comprise only one Y or may comprise more than one Y. If it is intended to use ‘comprise’ with an exclusive meaning then it will be made clear in the context by referring to “comprising only one ...” or by using “consisting”.

In this description, the wording ‘connect’, ‘couple’ and ‘communication’ and their derivatives mean operationally connected/coupled/in communication. It should be appreciated that any number or combination of intervening components can exist, e.g. an electrical junction, (including no intervening components). In this description, references to “α/αη/the” [feature, element, component, means ...] are to be interpreted as “at least one" [feature, element, component, means...] unless explicitly stated otherwise.

In this description, reference has been made fo various examples. The description of features or functions in relation to an example indicates that those features or functions are present in that example. The use of the term 'example' or ‘for example' or ‘may' in the text denotes, whether explicitly stated or not, that such features or tunctions are present in at least the described example, whether described as an example or not, and that they can be, but are not necessarily, present in some or all other examples. Thus ‘example', ‘for example' or ‘may' refers to a particular instance in a class of examples. A properfy of fhe insfance can be a property of only that instance or a property of the class or a property of a sub-class of the class that includes some but not all of fhe insfances in the class.

The above description describes some examples of the present disclosure however those of ordinary skill in the art will be aware of possible alternative structures and method features which offer equivalent functionality to the specific examples of such structures and features described herein above and which for the sake of brevity and clarity have been omitted from the above description. Nonetheless, the above description should be read as implicitly including reference to such alternative structures and method features which provide equivalent functionality unless such alternative structures or method features are explicitly excluded in the above description of the examples of the present disclosure.

Whilst endeavouring in the foregoing specification to draw attention to those features of examples of the present disclosure believed to be of particular importance it should be understood that the applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to and/or shown in the drawings whether or not particular emphasis has been placed thereon.

The examples of the present disclosure and the accompanying claims may be suitably combined in any manner apparent to one of ordinary skill in the art.

Claims (18)

CLAIMS We claim:

1. An apparatus comprising: a cable assembly having a first longitudinal section and at least a second longitudinal section, the cable assembly camprising: a first electrical path extending alang the first and at least second longitudinal sections, the first electrical path having a first section within the first longitudinal section and at least a second section within the at least second longitudinal section: at least a second electrical path extending along the first and at least secand langitudinal sections, the second electrical path having a first sectian within the first longitudinal section and at least a second section within the at least second longitudinal section; and wherein: the first section of the first electrical path is configured such that it is moveable within the first longitudinal sectian, the first section of the second electrical path is configured such that it is fixed wifhin fhe first longitudinal sectian, and the secand section of the second electrical path is configured such that it is moveable within the second longitudinal section.

2. The apparatus of claim 1, wherein: fhe second section of the first electrical path is configured such that it is fixed within the secand longitudinal sectian, ar the second section of the first electrical path is configured such that it is moveable within the second longitudinal section.

3. The apparatus of any one or more of the previous claims, wherein the apparatus is canfigured such that the first section of the first electrical path is loosely mounted within the first longitudinal section.

4. The apparatus of any one or more of the previous claims, wherein the first section of the first electrical path comprises an elongate conductor which is loosely housed within the first longitudinal section such that it is able to be moveable in a transverse direction.

5. The apparatus of any one or more of the previous claims, wherein the first longitudinal section comprises a first magnetic member.

6. The apparatus of claim 5, wherein the first section of the first electrical path is configured to be moveable relative to the first magnetic member.

7. The apparatus of claim 5 or 6, wherein the first section of the second electrical path is configured fo be fixed in position relative to the first magnetic member.

8. The apparatus of claim 5, 6 or 7, wherein the first magnetic member is elongate and extends along the first longitudinal section.

9. The apparatus of any one or more of the previous claims, wherein the first and at least second longitudinal sections comprises one or more elongate magnetic members extending along the first and at least second longitudinal sections.

10. The apparatus of any one or more of the previous claims, wherein the first longitudinal section comprises a first elongate hollow channel defining a first elongate void space within which the first section of the first electrical path is able to freely move.

11. The apparatus of any one or more of the previous claims, wherein the cable assembly comprises a plurality of longitudinal sections, the cable assembly comprising: a plurality of electrical paths each extending along the plurality of longitudinal sections, each electrical path comprising a plurality of sections that are either moveable or fixed within a particular longitudinal section, wherein, the apparatus is configured such that, for each longitudinal section, there is a unique combination of moveable and fixed sections of the plurality of electrical paths.

12. The apparatus of any one or more of the previous claims, wherein the cable assembly comprises 2'^ -1 longitudinal sections, the cable assembly comprising: N electrical paths each extending along the 2'^ -1 longitudinal sections, each electrical path comprising 2'^ -1 sections that are either moveable or fixed within a respective longitudinal section, wherein, the apparatus is configured such that, for each longitudinal section, there is a unique combination of moveable and fixed sections of the N electrical paths.

13. The apparatus of any one or more of the previous claims, wherein the apparatus is configured to be sensitive to vibrations applied to the cable assembly.

14. The apparatus of claim 13, wherein the first section of fhe firsf elecfrical pafh is configured such fhaf if is moveable wifhin fhe firsf longifudinal secfion in response fo a force applied fo fhe apparafus.

15. A module comprising fhe apparafus of any one or more of fhe previous claims.

16. A sysfem comprising: fhe apparafus of any one or more of previous claims 1 fo 15, wherein fhe apparafus is configured fo generafe one or more signals responsive fo one or more forces applied fo one or more of fhe longifudinal secfions; and means for processing signals received from fhe apparafus fo generafe an alert signal.

17. A perimeter security system comprising the apparatus of any one or more of previous claims 1 to 15 or module of claim 15.

18. A method of manufacturing the apparatus of any of claims 1 to 15.