GB2617098A

GB2617098A - A system for detecting unauthorised removal of material

Info

Publication number: GB2617098A
Application number: GB2204433.3A
Authority: GB
Inventors: Neal Forse
Original assignee: Iot Solutions Group Ltd
Current assignee: Iot Solutions Group Ltd
Priority date: 2022-03-29
Filing date: 2022-03-29
Publication date: 2023-10-04
Also published as: GB202204433D0

Abstract

A system for detecting the unauthorised removal of a layer or length of material comprises two or more sensor assemblies 100 which are arranged on a surface of the material 200 being monitored. A processor 300 associated with each sensor assembly 100 receives a signal indicating when the material is moved and/or changes orientation. The processor 300 upon receipt of signals from at least two sensor assemblies 100, within a predetermined time period, determines unauthorised removal of the material and issues an alert signal. The sensor assembly 100 may include a gyroscope, accelerometer, vibration sensor or strain sensor, and may be in wireless communication with the processor 300. The system is particularly suited for detecting the removal of lead from a church roof or copper cables from a rail network.

Description

A System for Detecting Unauthorised Removal of Material

Field of the Invention

The present invention relates to a system for detecting the unauthorised removal of material, in particular a layer of material such as a sheet of material, or a length of material such as a cable.

Background

Theft of valuable materials such as lead, and copper is a common problem. Not only can theft of the material cause damage, for example the removal of lead from a roof can result in water ingress, but the removal of some materials, such as copper can render a system inoperable, for example by damaging signal cables on a rail network. In addition to this the act of removing the valuable materials can be dangerous.

Although a vulnerable location such as a church roof or railway track may be monitored regularly, for example by performing daily checks, thefts typically occur during darkness and anti-social hours so that the theft goes unnoticed at the time.

Remote methods for detecting theft of materials such as lead, or copper include use of close circuit television or use of passive infrared sensors. However, the installation of such devices is costly due to product costs and installation costs. Furthermore such devices often require fixing to a structure such as roof by drilling holes, which damages the building.

The present invention provides a system to notify an authorised user when removal of a valuable material is underway.

Summary of the Invention

According to a first aspect of the present invention there is provided a system for detecting unauthorised removal of a layer or length of material comprising: at least two sensors which are arranged on a surface of the material being monitored; a processor is connected to each of the sensors to receive a signal indicating when the material is disturbed and wherein the processor is operative, upon receipt of a signal from the at least two sensors, within a predetermined time period, to indicate unauthorised removal of the material, to issue an alert signal.

In this way the unauthorised removal of a layer or length of material, for example a valuable material such as lead, or copper can be detected during removal.

Preferably the at least two sensors enable detection of an event that is indicative of a change in orientation of the material on which the sensors are mounted, and/or detection of strain to the material.

In a preferred embodiment the sensor to detect orientation that may be used as pad of the system is a solid state gyroscopic sensor.

In another embodiment at least one sensor is an accelerometer that is used to detect changes in orientation of the sensor.

In some embodiments at least one sensor may be pressure sensor, for example a sensor including an element for sensing strain.

In some embodiments the sensors include a vibration sensing element.

In a preferred embodiment at least one of the sensors is operative to detect a change in orientation. A first orientation of the sensor is determined at fitting and any change from the first orientation indicates movement of the surface upon, underneath or within which the sensor is fitted. When movement is detected, a signal is transmitted from the sensor to the processor. If two signals are received from at least two different sensors within a predefined time period, this is indicative of a removal of material event and an alert signal is transmitted by the processor to advise of unauthorised removal of material.

In a preferred embodiment an algorithm is provided in a computer implemented format which provides instructions to the processor to enable the signals received from the sensors to be analysed.

Preferably the data received from an orientation sensor is analysed to determine if the range of movement detected is within predefined parameters.

In preferred embodiments the degree of tilt is graded into categories. For example: Level 1 = more than 10 degrees of tilt from the fitted orientation is detected by at least two sensors Level 2 = more than 30 degrees of tilt from the fitted orientation is detected by at least two sensors Level 3 = more than 45 degrees of tilt from the fitted orientation is detected by at least two sensors Assessment of the category of tilt may help determine the whether the material is being removed, or if it has become loose or is being worked on.

Ideally the processor runs an algorithm that monitors severity of tilt in relation to time, so that the degree of tilt can also be considered with a predefined time period. For example, an incident of tilt that is less than 10 seconds may indicate a gust of wind displacing a leaf of lead, whereas repeated orientation changes during a time interval of, for example, 30 seconds to one minute, may indicate peeling of material from surface.

The sensors may be coloured to match the surface upon which they are placed in order to be discreet and so as not to distract from the original features of the building. For example the sensors may be grey to match lead, or may be substantially transparent or translucent.

The unauthorised removal of material is indicated by the alert signal. The alert signal is intended to advise that unauthorised removal of a material is in progress in order for action to be taken to prevent this.

The alert signal may be an alarm, a visual indicator such as a flashing light, or an alert message that is transmitted to a remote device or a combination of these alert signals.

In preferred embodiments an alert message is sent to an authorised user to alert them of theft and enable action to be taken. The alert signal may be in the form of a text message, email or push notification. Preferably the alert message is transmitted to a remote device, for example to a smartphone, tablet or computer.

In some embodiments an onsite alert may also be activated to serve as a deterrent or to alert people nearby of the incident.

In order to prevent erroneous alert signals being activated preferably the at least two signals must be detected within a predefined time period. In this way separate signals at completely different times of a day would not generate an alert.

Additionally, in order to prevent erroneous alert signals, the processor is operative to detect different sequences of activation of the sensors in order to be able to distinguish between authorised events, such as a bird landing on a lead roof or rainfall, and unauthorised events, such as theft of lead.

Preferably the processor is operative to determine whether the at least two sensors have been activated substantially simultaneously. As the sensors are spaced across the layer of material, movement of at least two sensors simultaneously indicates that the layer of material has been displaced.

Furthermore the processor may override the alert signal if an array of sensors are activated simultaneously, for example in the case of heavy rainfall.

In another preferred embodiment a plurality of sensors is arranged in an array and the processor is operative to determine whether the at least two sensors have been activated in a particular sequence. For example the processor may determine when a row of sensors are activated one after the other. In this way if sensors are detected in a sequence, for example across a length of the material, this indicates that the layer is being peeled from the surface upon which it is arranged.

It is appreciated that the sensors may be deployed as a two dimensional array or as a three dimensional array depending upon the material to be monitored.

The sensors are ideally spaced apart, preferably at regular spacings, on a layer or length of material. The sensors may be arranged in a uniform configuration for example in rows or as a grid, or may be arranged in a random formation.

Preferably at least one sensor is in contact with an edge portion of the layer of material or at an end of a length of material. This is because removal may typically start from this point and therefore detection at the commencement of removal of the material provides a greater likelihood of identifying and catching the perpetrator.

The sensors are connected to the processor so that a signal from each sensor is communicated to the processor. It is appreciated that each sensor has an individually identifiable signal so that one sensor signal can be determined from another.

In preferred embodiments at least one of the sensors is in wireless communication with the processor. Typically all sensors in the system are in wireless communication with the processor so that no wiring is required. This enables easy and quick fitting of the sensors and also enables sensors to be readily replaced without affecting the system.

It is appreciated that in some embodiments at least one sensor may be hard wired to the processor.

In preferred embodiments the processor is a microprocessor.

The processor is connected to a power source. The power source may include at least one battery, or a wired supply. Preferably the at least one battery is rechargeable.

In some embodiments at least one photovoltaic cell is provided to generate energy to charge the at least one battery, and/or to provide a direct power supply to the processor.

The sensors may be provided on an upper surface of a layer of material, on a lower surface of a layer of material, embedded in the layer of material or located in a combination of the before mentioned locations. Advantageously this enables the sensors to be fitted to suit the type of material and location of the material.

For example, if sensors are to be retro fitted to an existing fixed layer or length of material, such as a lead roof of a church, the sensors may be positioned upon the material. If the sensors are fitted at installation of a material, some or all of the sensors, may be fitted under the material to prevent access to the sensors and to enable them to be protected from the elements.

Preferably the sensors may be fixed to a surface with adhesive, so that the surface is not altered or damaged in any way.

The system may include a wireless receiver for receiving updates to software.

Preferred embodiments of the invention will now be described, by way of example and with reference to the Figures in which:

Brief Description of Figures

Figure 1 shows a first embodiment of a sensor for positioning on a roof; Figure 2 shows an exploded view of the first embodiment; and Figure 3 shows an array of sensors arranged on a roof.

Detailed Description of Figures

The first embodiment of the sensor assembly 100 has a lower housing 10, and upper housing 20 that are sealed together with a gasket 30 so as to form a watertight enclosure which holds the component parts of the sensor 100.

The lower housing 10 has a flat base and an upward extending wall that corresponds to the shape of the upper housing 20. The upper housing 20 is domed and has a lozenge shaped footprint that corresponds to the wall of the lower housing 10.

The components within the housing 10, 20 include a printed circuit board (PCB) 40 and a battery 50.

The PCB 40 houses at least one sensor (not shown) that detects movement and/or change of orientation and a transmitter (not shown) to transmit a signal from the at least one sensor to a remote device 300 with a receiver (see Figure 3).

A resiliently deformable packing sheet 41 is provided between the battery 50 and the upper housing 20. The packing sheet limits movement of parts within the housing and thereby may assist with the accuracy of the sensors as erroneous movement of internal parts is restricted. The resiliently deformable packing sheet 41 is preferably formed from a cellular structure such as foam.

The upper housing 20 has a label 21.

The upper housing 20 has four apertures 22 for receiving fixing bolts 15. The apertures 22 in the upper housing 20 correspond to four holes 11 in the lower housing so that the bolts 15 pass through both the apertures 22 and holes 11 to join the two parts of the housing 10, 20 and form a watertight enclosure.

Figure 3 shows an array of sensor assemblies 100 arranged on a roof 200 of a building. The sensor assemblies 100 are in wireless communication with a remote device 300.

The system has a method of operation having the steps of: a first sensor detecting an event and sending a signal to a processor; a second sensor detecting an event and sending a signal to the processor; the processor analysing the signals to determine if they have been received within a predefined time period; transmitting an alert signal to an alert means when at least two signals, from at least two different sensors, indicating an event are received with the predefined time period to obtain an indication of a malicious attack.

The remote device has a processor for analysing the signals received and generating an alert if a predefined criteria is met. An alert may be activated by transmission of a signal from the remote device to an alert means such as an alarm.

The invention has been described by way of examples only and it will be appreciated that variation may be made to the above-mentioned embodiments without departing from the scope of protection as defined by the claims.

Claims

Claims A system for detecting unauthorised removal of a layer or length of material comprising: at least two sensor assemblies which are arranged on a surface of the material being monitored; at least one processor is operatively connected to each of the sensor assemblies to receive a signal indicating when the material is disturbed and wherein the at least one processor is operative upon receipt of signals from at least two sensor assemblies within a predetermined time period, to indicate unauthorised removal of the material by issuing an alert signal.
A system according to claim 1 wherein the at least one processor is operative to determine whether the at least two sensor assemblies have been activated substantially simultaneously.
A system according to claim 1 or 2 wherein a plurality of sensor assemblies is arranged in an array and the processor is operative to determine which of the at least two sensors have been activated in a particular sequence.
A system according to any preceding claim wherein at least one sensor assembly is in contact with an edge portion of the layer of material or with an end of a length of material.
5. A system according to any preceding claim wherein at least one sensor assembly is provided on an upper surface of a layer or length of material.
A system according to any preceding claim wherein at least one sensor assembly is provided on a lower surface of a layer or length of material.
7. A system according to any preceding claim wherein at least one sensor assembly is embedded in the layer or length of material.
A system according to any preceding claim wherein at least one of the sensors is a solid state gyroscopic sensor.
9. A system according to any preceding claim wherein at least one of the sensors is an accelerometer.
10. A system according to any preceding claim wherein the sensors include a vibration sensing element.
11. A system according to any preceding claim wherein the sensors include an element for sensing strain.
12. A system according to any preceding claim wherein at least one of the sensors is in wireless communication with the processor.
13. A system according to any preceding claim wherein at least one of the sensors is hard wired to the processor.
14. A system according to any preceding claim wherein an algorithm is provided in a computer implemented format which provides instructions to the processor.
15. A system according to any preceding claim wherein the processor is connected to and receives signals from a wireless receiver, for example to receive updates to software.
16. A system according to any of claims 1 to 14 wherein the processor has at least one port for receiving data.
17. A method of using the system described in claims 1 to 16 comprising the steps of: detecting an event using a first sensor and sending a first signal to a processor; detecting an event using a second sensor and sending a second signal to the processor; processing the first and second signals at the processor and analysing the processed signals to determine if the two signal have been received within a predefined time period to obtain an indication of a malicious attack; and transmitting an alert signal to an alert means when a malicious attack is detected.