WO2021168499A1

WO2021168499A1 - Device, system and method for detecting soiling matter on a surface

Info

Publication number: WO2021168499A1
Application number: PCT/AU2021/000018
Authority: WO
Inventors: Stuart Andrew CARR; James Francis O'BRIAN; Cory Wright
Original assignee: Lifespan Energy Pty Ltd
Priority date: 2020-02-25
Filing date: 2021-02-24
Publication date: 2021-09-02

Abstract

The invention relates to a device, a system and methods thereof for detecting soiling matter on a surface. The device comprises a housing, an optical surface incorporated within the housing to accumulate soiling matter, one or more photosensors arranged to at least receive an optical signal transmitted through or redirected from the optical surface that may be soiled and to acquire optical data in relation to soiling, a communication means to transmit the optical data to an external computer, and a power generation means; and wherein power required to operate the device is entirely or substantially provided by the power generation means. The system and methods described utilise a device in accordance with the described device.

Description

TITLE ‘Device, System and Method for Detecting Soiling Matter on a Surface”

EIELD OE THE INVENTION

[0001] The present invention relates to a device, a system and methods thereof for detecting soiling matter on a surface, in particular on an outdoor surface with a tendency to soil and a requirement to remain relatively clean.

BACKGROUND

[0002] The accumulation of soiling matter on surfaces, particularly dust in outdoor settings, can be detrimental to the functioning of a lot of machinery and technology.

[0003] The soiling matter has to be cleaned off to maintain the machinery and technology in proper working order. However, determining the level of soiling and whether a surface has to be cleaned may be a challenging task as the surface may not be conveniently visible or accessible. The task may be labour intensive if executed manually, or routinely, particularly when the accumulation of soiling matter may not be constant or consistent.

[0004] One surface where soiling matter can accumulate is on photovoltaic panels, commonly referred to as solar panels. A photovoltaic panel relies on collecting as much solar energy as possible to generate power, thus when the photovoltaic panel is dirtied by soiling matter, the soiling blocks sunlight and reduces the efficiency of power generation.

[0005] Known in the present state of the art of detecting whether a photovoltaic panel is soiled, and thus require cleaning, are comparative output measuring devices and methods. Such type of detection is typically applied to industrial and large commercial arrays of photovoltaic panels, due to factors such as cost and the technical

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SUBSTITUTE SHEET (Rule 26) RO/AU knowledge required to operate them. Data acquired by such devices are typically hardwired into a networked system with a proprietary system interface.

[0006] Comparative output measuring involves having at least two test photovoltaic cells arranged near an array of photovoltaic panels to be monitored. One photovoltaic cell is kept clean whilst the other is left to accumulate soiling matter naturally. The difference between the outputs of the photovoltaic cells is measured and a signal to indicate that the solar array (and dirty photovoltaic cell) needs to be cleaned is generated when the difference reaches a predetermined value.

[0007] For residential photovoltaic panels, determining whether cleaning is required still largely relies on the manual method of a person climbing onto the rooftop to check the amount of soiling through visual inspection. Such an operation is labour intensive, risky and impractical to be carried out regularly.

[0008] Other than photovoltaic panels, another exemplary surface where soiling matter can accumulate and cause damage or even lead to serious consequences is on certain top surfaces of utility poles. In this instance, condensed moisture (from the air or light rainfall) mixes with soiling matter accumulated on a top surface of a utility pole to create a conductive path for electricity. The conductive path may form across a cross arm of the pole, for example. Along the conductive path, an electric current may arc or spark and ignite the soiling matter or the utility pole materials (particularly, causing fire). Such utility pole fires (which may be referred to as “pole top fires”) are common, particularly in dry, semi-arid regions such as parts of Australia and the United States of America. This type of fire tends to damage system components, cause power outages, or even spark a bushfire or wildfire.

[0009] It is impractical, or even impossible, to manually inspect all the utility poles of a utility system in terms of soiling level, due to the sheer quantity of utility poles, the (often remote) locations of the utility poles, the height of the utility poles, and other circumstances, such as severe weather events during periods of inspection.

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SUBSTITUTE SHEET (Rule 26) RO/AU [0010] The present invention attempts to overcome at least in part the aforementioned problems or challenges associated with detecting soiling matter on a surface in an outdoor application, in order to avoid hazards or enable an equipment to operate at a desired efficiency.

SUMMARY OF THE INVENTION

[0011] In accordance with a first aspect of the present invention there is provided a device for detecting soiling on a target surface, comprising: a housing, an optical surface incorporated within the housing to accumulate soiling matter, one or more photosensors arranged to at least receive an optical signal transmitted through or redirected from the optical surface that may be soiled and to acquire optical data in relation to soiling, a communication means to transmit the optical data to an external computer, and a power generation means; wherein power required to operate the device is entirely or substantially provided by the power generation means.

[0012] In a preferred embodiment, the power generation means comprises a photovoltaic cell and a rechargeable battery'.

[0013] In a preferred embodiment, the device according to the first aspect of the present invention further comprises a mounting means, for mounting the device to a target surface to which the device is to be applied to obtain a representative measurement thereof. Preferably, the mounting means enables the device to be removably fixed to the target surface, thereby enabling the device to be installed or reinstalled at desired locations.

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SUBSTITUTE SHEET (Rule 26) RO/AU [0014] In a further embodiment, the mounting means may be an articulated clamp, which enables the device to be orientated such that the optical surface (to accumulate soiling matter) has a similar or substantially same inclination to the target surface.

[0015] In one embodiment, the photosensor comprises at least a photoreceptor element. In another embodiment, the photosensor comprises a photoemitter element and a photoreceptor element. In a further embodiment, the device according to the first aspect of the present invention comprises a plurality of photosensors having both a photoemitter element and a photoreceptor element.

[0016] In one embodiment, the device according to the first aspect of the present invention further comprises a data processing means to process the optical data acquired by the photosensor(s) to determine the level or extent of soiling, or to transform the optical data into a desired data format for storage and/or communication. The data processing means comprises at least a processing algorithm to process the optical data. In one embodiment, the processed data may be sent by the processing means to the communication means according to the first aspect of the present invention, for further transmission to an external computer.

[0017] In one embodiment, the communication means of the device according to the first aspect of the present invention further comprises a cellular networking system.

[001 ] In another embodiment, the communication means further comprises a wireless local area networking system.

[0019] In one embodiment, the external computer is a server which stores the processed or unprocessed optical data in relation to soiling, or transmits the data to a software application accessible from a mobile device.

[0020] In a preferred embodiment, when the processed or unprocessed optical data in relation to soiling, reaches or exceeds a predetermined value or falls within a predetermined range, then an electronic notification is generated by and sent from the

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SUBSTITUTE SHEET (Rule 26) RO/AU external computer to an email address or a software application accessible from a mobile device. The electronic notification may be an alert, a message or an instruction.

[0021] In a preferred embodiment, the device is easily portable so as to be able to be carried by a single person. This is particularly preferred where the installation of the device is to be on a roof or a place of height where the person may have to carry the device and move up a ladder to reach the installation position.

[0022] In accordance with a second aspect of the present invention there is provided a system for acquiring representative optical data in relation to soiling of a target surface and notifying a user, the system comprising: a detection device, as per the first aspect of the present invention, configured to acquire representative optical data in relation to soiling of the target surface and transmit the optical data, an external computer configured to receive, store and/or further transmit the optical data, and a mobile device in communication with the external computer and accessible by the user; wherein the mobile device is capable of retrieving or receiving the optical data in relation to soiling from the external computer, and/or capable of receiving a notification from the external computer and/or sending a notification to the user when the optical data in relation to soiling reaches or exceeds a predetermined value or falls within a predetermined range.

[0023] In one embodiment, the device according to the first aspect of the present invention comprises a data processing means to process the optical data acquired by the photosensor(s) to detennine the level or extent of soiling, the data processing means comprising at least a processing algorithm to process the acquired optical data.

[0024] In a preferred embodiment, the power generation means comprises a photovoltaic cell and a rechargeable battery.

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SUBSTITUTE SHEET (Rule 26) RO/AU [0025] In a preferred embodiment, the device according to the first aspect of the present invention further comprises a mounting means, for mounting the device to the target surface to which the device is to be applied.

[0026] In one embodiment, the communication means further comprises a cellular networking system.

[0027] In another embodiment, the communication means further comprises a wireless local area networking system.

[0028] In a further embodiment, the communication means in the device according to the first aspect of the present invention transmits the optical data via a wireless connection.

[0029] In one embodiment, the external computer is a server which stores the processed or unprocessed optical data and/or transmits the data to a software application accessible from a mobile device.

[0030] In a further embodiment, when the processed or unprocessed optical data in relation to soiling reaches or exceeds a predetermined value or falls within a predetermined range, then an electronic notification is generated and sent by the external computer to an email address or a software application accessible from the mobile device. The electronic notification may be an alert, a message or an instruction.

[0031 ] In accordance with a third aspect of the present invention there is provided a method of detecting a representative state of soiling of a target surface using a device according to the first aspect of the invention, whereby the method comprises the steps of, mounting the device on or adjacent to the target surface, enabling soiling matter to accumulate on the optical surface,

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SUBSTITUTE SHEET (Rule 26) RO/AU acquiring optical data in relation to soiling through the one or more photosensors at a predetermined interval, and transmitting the optical data in relation to soiling to an external computer.

[0032] In one embodiment, the device is preferably orientated in the same plane and direction as the target surface.

[0033] In one embodiment, the target surface is a photovoltaic panel or a utility pole surface.

[0034] In accordance with a fourth aspect of the present invention there is provided a method of using a system according to the second aspect of the present invention to notify a user a representative state of soiling of a target surface, whereby the method comprises the steps of, mounting a device according to the first aspect of the present invention on or adjacent to a target surface; acquiring optical data in relation to soiling by measuring one or more optical signals transmitted through or redirected by the optical surface that may be soiled; transmitting the optical data to an external computer or a mobile device in communication with the external computer; and sending an electronic notification to the user at a predetermined interval, or when the optical data in relation to soiling reaches or exceeds a predetermined value or falls within a predetermined range.

[0035] In one embodiment, the device according to the first aspect of the present invention comprises a data processing means to process the optical data acquired by the photoscnsor(s) to determine the level or extent of soiling, the data processing means comprising at least a processing algorithm to process the acquired optical data.

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SUBSTITUTE SHEET (Rule 26) RO/AU [0036] In a preferred embodiment, the power generation means comprises a photovoltaic cell and a rechargeable battery.

[0037] In a preferred embodiment, the device according to the first aspect of the present invention comprises a mounting means to enable the mounting of the device to the target surface.

DEFINITIONS

[0038] Unless otherwise indicated, the following terms used in this disclosure have the following meanings:

[0039] Soiling Matter

[0040] The term “soiling matter” as used herein refers to one or more substances that inhabit a target surface (e.g. a surface of a piece of equipment in an outdoor setting). Soiling matter can include a variety of substances depending on the environment. For the purposes of this specification the term ‘soiling matter’ includes but is not limited to dust, dirt, debris, soil, sand, bacteria, coal dust, salt, ash, flour, sawdust, faeces, pollen and other particulate matter found in outdoor settings.

[0041] Housing

[0042] The term “housing” as used herein refers to a body, casing or a cover that encloses and protects internal components and/or holds, integrates or incorporates external components of the device according to the first aspect of the present invention. The housing is preferably weatherproof and resistant to deterioration due to exposure to the environment.

[0043] Mounting means

The term “mounting means” as used herein refers to a means for affixing the device according to the first aspect of the invention to a target surface or a target object. Preferably, the mounting means enables the device to be removably fixed to the target surface or target objection. Preferably, mounting the device using the mounting

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SUBSTITUTE SHEET (Rule 26) RO/AU means does not require further tools. Preferably, the mounting means is detachable from the device so as to aid with packing, transportation and re-use of the device.

[0044] In one preferred embodiment, the mounting means is an articulated clamp, being a clamp for affixing the device to a target surface or object wherein the device is moveable relative to the clamp. Advantageously, this permits the device, in particular the optical surface, to be inclined or aligned at an angle or in a direction similar to or substantially the same as the target surface, to enable a more precise or more representative measurement of soiling on the target surface. The articulated clamp also permits the device to be adjusted or repositioned with relative ease.

[0045] Optical Surface

[0046] The term “optical surface’" as used herein refers to a surface disposed to accumulate soiling matter, the surface being formed of an optical material (selected from glass, crystalline materials, polymer or plastic materials) which permits the flow of light through the material. At the state of zero soiling, 100% or substantially 100% of the optical signal is able to be transmitted through the optical surface. As the level or extent of soiling increases, the optical signal is increasingly blocked or reflected by the soiling matter, leading to, for example, only 40% to 85% of the sunlight signal being transmitted through the optical surface carrying the soiling matter, or 25 - 75% of the optical signal being reflected by the optical surface due to the accumulated soiling matter.

[0047] Photosensor

[0048] The term “photosensor” as used herein refers to a component of the device according to the first aspect of the present invention that is able to sense an optical signal. In one embodiment, the photosensor has a photoreceptor, capable of sensing an optical signal, e.g. a sunlight signal, transmitted through the optical surface (soiled or unsoiled). In another embodiment, the photosensor has a photocmittcr capable of emitting an optical signal through the (soiled or unsoiled) optical surface, and a photoreceptor capable of receiving the optical signal reflected back by the (soiled or unsoiled) optical surface. In one embodiment, the photosensor may comprise both a

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SUBSTITUTE SHEET (Rule 26) RO/AU photoemitter and a photoreceptor element in one combined module. In another embodiment, the photoemitter and photoreceptor may be present as two separate elements (i.e. a photoemitter element and a photoreceptor element). An array of photosensors may be able to perform the function of a photosensor as described herein.

[0049] Optical Signal

[0050] The term “optical signal” as used herein refers to an electromagnetic signal, such as a light signal selected from a visible light signal, an infrared signal or an ultraviolet signal. In one embodiment, the optical signal is a light signal emitted by an external source (such as the sun). In another embodiment, the optical signal may be a light signal emitted by the photosensor in the device according to the first aspect of the present invention, wherein the photosensor comprises a photoemitter element. The optical signal may be subject to signal generation or processing techniques (e.g. the signal may be a stable signal, a pulsed signal or a combination of stable and pulsed).

[0051] The optical signal may be a single discrete signal. In other embodiments, multiple, intermittent or continuous optical signals may be sent, transmitted, reflected and/or received by the photosensor

[0052] The optical signal may be measured in the form of transmittance and/or reflectance measurements

[0053] In a specific embodiment, the photosensor having a photoemitter element may emit an infrared beam as an optical signal. If there is no soiling on the optical surface of the device according to the first aspect of the present invention, then the infrared beam would be transmitted (at 95% to 100% efficiency) through the optical surface into a surrounding environment. When soiling is present, the infrared beam would be reflected towards the photoreceptor clement and the photoreceptor output is measured.

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SUBSTITUTE SHEET (Rule 26) RO/AU [0054] The optical signal may be measured at a desired time interval or frequency, e.g. one or more times a day, a week, a month or a year. Desired intervals and frequencies may vary due to a variety of factors such as factors such as data collection requirements, seasonal conditions, local sunrise/sunset times or El Nino/La Nina climate patterns.

[0055] Optical Data

[0056] The term “optical data” as used herein refers to information regarding an optical signal, or a set of optical signals. In one embodiment, optical data may comprise a set of multiple readings produced by one or multiple sensors within a predetermined time interval.

[0057] Optical data may also include additional information including, but is not limited to, ambient parameters (e.g. temperature), detection times, location data, luminance, illuminance or intensity data.

[0058] Optical data may be a single data point, a single value, a single averaged value, or a set of data points or values.

[0059] Optical data may be unprocessed (raw) output(s) from one or more photosensors, raw measurements of incident light (e.g. sunlight), or processed data (from one or more photosensors) such that the raw or initial measurements have been processed by the data processing means according to the present invention. The optical data may be stored and/or transmitted in an unprocessed or processed state. Processed data may exclude specific data entries in the raw data, for example where some of the raw data is determined to be corrupted or presenting data outside of a specified threshold range.

[0060] The term “optical data in relation to soiling” as used herein refers to information pertaining to the state, level or extent of soiling. For example, as soiling matter accumulates on the optical surface, the transmission of sunlight through the optical surface may be reduced. In another embodiment where the optical signal in

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SUBSTITUTE SHEET (Rule 26) RO/AU the form of an infrared beam is emitted by the photoemitter element, the amount or intensity of infrared light reflected by the soiling matter back to the photoreceptor element would increase with an increasing level of soiling on the optical surface. Therefore, in one embodiment, the optical data in relation to soiling may be represented as a percentage, or as percentages, of the initial measurement or the calibrated state (of transmittance or reflectance) when the optical surface is substantially clean.

[0061] In one embodiment, optical data in relation to soiling may be an averaged and/or processed data value in the form of a percentage denoting the percentage of soiling, or the percentage of the initial or calibrated optical signal transmittance or reflectance measurement when the optical surface is in a clean state (with no or substantially no soiling). The percentage value may be between 0% and 100%. In one embodiment, 0% is the reading of the calibrated clean state, and 100% would be a calibrated maximum reflectivity state (which may represent 100% soiling) in a preferred embodiment, the percentage may be a predetermined value which would indicate that the soiling had reached a critical or undesired level. For example, the predetermined value may be a value in the range of 25% to 80% transmittance, or a value in the range of 10% to 60% reflectance. In another embodiment, the predetermined value may be a value in the range of 15% to 50%, 18% to 45% or 20% to 40% reflectance. For example, the predetennined value may be 25% reflectance of the optical signal, indicating soiling has reached a critical or undesired level. Alternatively, the data may be processed into other equally acceptable mathematical forms and/or scales including but not limited to fractional values and/or logarithmic scales.

[0062] External Computer

[0063] The term “external computer” as used herein refers to a computational device separate from the detection device according to the first aspect of the present invention. An external computer in the context of the present invention includes, but is not limited to, a single computer such as a stand-alone PC, a computer network, or a server. In one preferred embodiment, the external computer is a server.

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SUBSTITUTE SHEET (Rule 26) RO/AU [0064] Mobile Device

[0065] The term mobile device as used herein refers to a computational device that is portable. A mobile device in the context of the present invention includes, but is not limited to, a cellular phone, a laptop computer, a tablet computer, a personal digital assistant or a smart watch.

[0066] An external computer may also be capable of fulfilling the functions of a mobile device (such as notifying a user of the optical data in relation to soiling). Therefore, the external computer and mobile device may be of a unitary construction. For example, a laptop computer may be capable of facilitating both the functions of the external computer and the mobile device (e.g. capable of storing processed or unprocessed data in relation to soiling and sending a notification to a user).

[0067] Throughout this specification, the term “comprise”, or variations thereof such as “comprises” and “comprising”, is used in an open-ended manner, to mean inclusive of a stated feature, element, step or integer, but not to the exclusion of any other feature, element, step or integer.

BRIEF DESCRIPTION OF DRAWINGS

[0068] The present invention will now be described, by way of example, with reference to the accompanying drawings, in which:

[0069] Figure 1 is a perspective view of a device for detecting soiling on a target surface according to the first aspect of the present invention having an articulated clamp arranged in an open and flat manner.

[0070] Figure 2 is a top view of the device of Figure 1.

[0071] Figure 3 is a right side view of the device of Figure 1.

[0072] Figure 4 is a left side view of the device of Figure 1.

[0073] Figure 5 is a front view of the device of Figure 1.

[0074] Figure 6 is a back view of the device of Figure 1.

[0075] Figure 7 is a bottom view of the device of Figure 1.

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SUBSTITUTE SHEET (Rule 26) RO/AU [0076] Figure 8 is a perspective view of the device of Figure 1 with the articulated clamp open and arranged at an angle.

[0077] Figure 9 is a perspective view of the device of Figure 1 with the optical surface removed.

[0078] Figure 10 is a block diagram showing the components of a device according to the first aspect of the present invention.

[0079] Figure 11 is a block diagram showing the components of a further embodiment according to the first aspect of the present invention.

[0080] Figure 12 is a block diagram of a system according to the second aspect of the present invention.

[0081] Figure 13 is a diagram showing a device according to the first aspect of the present invention detecting soiling matter on the optical surface using an optical signal emitted from and reflected back to the photosensor.

[0082] Figure 14 is a diagram showing another embodiment of a device according to the first aspect of the present invention detecting soiling matter on the optical surface using an optical signal emitted from an external source (such as the sun).

[0083] Figure 15 is a perspective view showing the device of Figure 1 mounted on a photovoltaic cell.

[0084] Figure 16 is a side view of the arrangement of Figure 15.

[0085] Figure 17 is a perspective view showing another arrangement of a photovoltaic cell with the device of Figure 1 mounted adjacent to the photovoltaic cell.

[0086] Figure 18 is a side view of the arrangement of Figure 17.

[0087] Figure 19 is a perspective view of a utility pole with the device of Figure 1 mounted to a cross beam of the utilit pole.

DETAILED DESCRIPTION

[0088] In accordance with a first aspect of the invention there is provided a device for detecting soiling on a target surface, comprising a housing, an optical surface incorporated within the housing to accumulate soiling matter, one or more photosensors arranged to at least receive an optical signal transmitted through or

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SUBSTITUTE SHEET (Rule 26) RO/AU redirected from the optical surface that may be soiled and to acquire optical data in relation to soiling, a communication means to transmit the optical data to an external computer, and a power generation means.

[0089] The power requirements for the device are entirely or substantially provided by the power generation means. This allows the device to function without causing additional energy drain on existing systems and/or operate without human intervention for long periods of time. Thus, the device can be utilised effectively in hard to reach areas and locations. This also renders the device highly mobile or adaptable in that it may function anywhere outdoors or on any target surface.

[0090] The device may further comprise components that form a secondary detection system including an ambient light sensor, an ambient temperature sensor and a low voltage detector. The secondary detection system provides information that may be used to determine the functional parameters of the device. The ambient light sensor may allow the device to determine whether to rely on an optical signal from a natural photoemitter (e.g. the sun) or an optical signal from an artificial photoemitter (e.g. an inbuilt photoemitter element) for detection purposes, and will allow the device to measure the background incident light for calibration purposes and reduce the likelihood of false readings and noise. An ambient light sensor and/or an ambient temperature sensor may allow the device to determine whether the device should function or not (e.g. whether a reading should be taken). The low voltage detector allows the device to monitor the output of the power generation means.

[0091] The secondary detection system may further include a sensor for detecting longitude and latitude.

[0092] Whilst the device may function without being mounted or affixed at the location of installation, a mounting means allows for the device to be secured so as not to dislodge or orient in an improper manner, particularly in outdoor conditions such as strong winds.

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SUBSTITUTE SHEET (Rule 26) RO/AU [0093] Preferably, the mounting means is articulated (e.g. an articulated clamp) allowing the device to be suitable for use in a variety of positions without the need for excessive remodelling. More preferably, where the mounting means is articulated the articulation is rigid enough to withstand forces from environmental conditions (wind, rain, hail, etc.) whilst maintaining the device at the appropriate orientation. Preferably, the mounting means is detachable from the device so as to aid with packing and transportation of the device.

[0094] The device may further comprise hard interface elements, such as buttons, light emitting diode indicators and/or a screen. These elements may be used to control or calibrate the device these elements may be used to indicate when a reading is being taken, when data is being transferred or when there are errors, such as an unexpected loss in communication with the external computer.

[0095] The device may further comprise a voltage control component between the computational unit and photoemitter to further control the output of the photoemitter.

[0096] The device may further comprise a data processing means to process the optical data acquired by the photosensor to determine the level or extent of soiling, the data processing means at least comprises a processing algorithm to process the acquired optical data. The data processing means may be incorporated with the computation unit, or as a separate component. The computational system allows for the device to determine conditions without the need for connection back to an external system, and may include clock and/or scheduling features. The clock and/or scheduling features may allow the device to operate (take readings and communicate data to the external computer) autonomously.

[0097] The external computer may be a server that processes the optical data to determine the extent of soiling and sends the processed data to a software application accessible from a mobile device.

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SUBSTITUTE SHEET (Rule 26) RO/AU [0098] Multiple mobile devices may be in communication with the external computer.

[0099] The communication means may include a wireless local area networking system comprising a processing module and an internal antenna. The wireless local area networking system will allow the device to connect to routers, backend servers, computers and mobile devices. A wireless connection removes the necessity for either an established cable connection to an external system or an operator needing to manually acquire data from the device.

[0100] The communication means may include a cellular networking system comprising a processing module, an internal antenna, a SIM card interface and a SIM card. The cellular networking system will allow the device to connect to cell towers, and through the cellular network to backend servers, computers and mobile devices. A wireless connection removes the necessity for either an established cable connection to an external system or an operator needing to manually acquire data from the device.

[0101] The SIM card interface may be fully enclosed within the housing or be incorporated with the housing so as to allow' access for a user to install one or more SIM cards without having to open the housing and potentially expose internal components to the environment

[0102] The device may be accessed and controlled remotely though software accessible on external computers and/or mobile devices.

[0103] The external computer may be, may incorporate or may be incorporated within a building management system (BMS).

[0104] The communication means may support the utilisation of security protocols to protect data communication.

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SUBSTITUTE SHEET (Rule 26) RO/AU [0105] The communication means may support the utilisation of a unique digital identifier for the device. Preferably, transmissions of the optical data incorporate the unique digital identifier.

[0106] The power generation means may comprise a solar cell, a charge circuit, a rechargeable battery and/or a DC/DC converter. The solar cell is arranged to collect sunlight and may be covered by a transparent photovoltaic cell covering designed to protect the photovoltaic cell from environmental conditions. The optical surface and the transparent photovoltaic cell covering may be of unitary construction.

[0107] t he power generation means enables the device to be suitable for installation at hard-to-reach or remote locations, such as photovoltaic panels on the roof of a house or atop utility poles, for extended periods of time without the need for drawing power from external systems or internal single-use batteries that may regularly deplete and need replacing. Preferably, the power generation means is capable of storing enough energy to allow the device to operate for at least one month. More preferably, the power generation means is capable of storing enough energy to allow the device to operate for at least one year. Even more preferably, the power generation means is capable of storing enough energy to allow the device to operate indefinitely.

[0108] The optical surface must be of sufficient transparency to allow for the transference of optical signals in a manner such that a photoreceptor can differentiate optical signal readings. Preferably, the optical surface is completely transparent. An appropriate material for the optical surface is glass. Alternatively, the optical surface may be semi-transparent.

[0109] The device may include a detection system for monitoring energy usage, energy generation and/or energy storage. Preferably, the data recorded by the detection system is incorporated with the optical data and is communicated to the external computer. More preferably, the detection system is capable of distinguishing when the device has energy storage levels below a selectable threshold or range.

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SUBSTITUTE SHEET (Rule 26) RO/AU Should the energy storage levels fall below the selected threshold or into the selected range then a notification may be sent via the communication means to the external computer and/or a mobile device. Preferably, the threshold is within 10% to 20% of the energy storage capacity of the device.

[0110] The mounting means may produce a staggered or ratcheting closure movement.

[0111] Referring to the Figures 1-8, there is shown an embodiment of a device 10, in accordance with a first aspect of the invention. Figures 1-8 depict the externally visible components of a housing 20, an optical surface 30 incorporated within the housing 20 and a mounting means 90 in the form of an articulated clamp. The embodiment further comprises the following internal components: a photosensor to acquire optical data, a communication means to transmit optical data to an external computer, a computational unit and a power generation means. The internal components are located within the housing 20 and are not depicted in Figures 1-8. The target surface to which the device 10 is to be applied is not depicted in Figures 1- 8. An external computer is not depicted in Figures 1-8.

[0112] The housing 20 is a box with rounded edges comprised of an upper housing section and a lower housing section joined together. A seam where the upper housing section and the lower housing section are joined is depicted in Figures 1, 3-6 and 8.

[0113] One side of the housing 20 is a curved surface and has a cavity in which the mounting means 90 is disposed.

[0114] The opposed side of the housing 20 to the curved surface is Hat and slanted such that the top of the housing 20 is slightly larger than the bottom of the housing 20.

[0115] Figures 3 and 7 depict the housing 20 with an access panel for a SIM card on one side.

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SUBSTITUTE SHEET (Rule 26) RO/AU [0116] The optical surface 30 is flat and rectangular with rounded corners incorporated on the top surface of the housing 20.

[0117] The mounting means 90 comprises: an upper section, a lower section, and a toothed track (teeth not depicted for clarity) with a stop; wherein the upper section is immovable relative to the toothed track and the lower section is movable relative to the toothed track The upper section and stop are disposed at opposite ends of the toothed track.

[0118] The mounting means 90 is disposed in the cavity of the housing 20.

[0119] The mounting means 90 is pivotally attached to the housing 20 on two sides of the cavity so as to be rotatable about an axis defined by the points of attachment. Preferably, the pivoting of the mounting means 90 is loose enough to be manipulated by hand but firm enough for the mounting means 90 to retain a set position.

[0120] The mounting means 90 is depicted as being in an open position wherein the lower section is located adjacent the stop.

[0121] In Figures 1-7, the mounting means 90 is depicted as being in a flat position where the mounting means 90 oriented to grip an object to the side of the device 10. In Figure 8, the mounting means 90 is depicted as being in an angled position where the mounting means 90 oriented to grip an object below the device 10

[0122] The mounting means 90 grips an object between the upper section and the lower section.

[0123] The lower section engages with the teeth of the toothed track in a ratcheting relationship. The teeth of the toothed track prevent the lower section from moving towards the stop.

20

SUBSTITUTE SHEET (Rule 26) RO/AU [0124] The mounting means 90 can be changed to a closed position by moving the lower section closer towards the upper section until both sections are in contact with the object to which the device 10 is to be mounted, for example a side of a solar panel.

[0125] In one embodiment, the lower section may further comprise a screw fastener arranged to secure the lower section to the toothed track when the mounting means 90 is in a closed position.

[0126] In an alternative embodiment the upper section is moveable relative to the toothed track and the upper section incorporates a counter-lever arranged to secure the lower section to the toothed track when the mounting means 90 is in a closed position.

[0127] A device according to the present invention may comprise multiple photoreceptors, either as part of a photosensor, as parts of multiple photosensors or as separate components, preferably spaced at least 40mm apart from one another. This is to allow for the device to prevent a situation whereby a single measurement may be influenced by a severe localised concentration of soiling matter, such as bird faeces, thereby generating a reading may not be indicative of the soiling of the target surface. Preferably, the device incorporates at least 2 photosensors. More preferably, the device incorporates at least 3 photosensors. Even more preferably, the device incorporates at least 5 photosensors.

[0128] Figure 9 depicts an embodiment of the device 10 substantially similar to the embodiment depicted in Figures 1-8 with the optical surface 30 removed for visualisation purposes, showing an array of three photosensors 40 spaced apart.

[0129] Figure 10 is a block diagram of an embodiment in accordance with the first aspect of the invention. The device 10 comprises a housing 20, an optical surface 30, a photosensor 40 (incorporating a photoemitter 42 and a photoreceptor 44 represented as discrete blocks), a communication means 60 to transmit optical data to an external

21

SUBSTITUTE SHEET (Rule 26) RO/AU computer, a computational unit 62 and a power generation means 70. An external computer is depicted. The target surface is not depicted. Dust is used to represent the soiling matter.

[0130] The power generation means 70 fulfils the power requirements of the device 10

[0131] Figure 11 is a block diagram of an embodiment in accordance with the first aspect of the invention in which the embodiment depicted in Figure 10 further incorporates a secondary detection system, additional sub-elements of the communication means 60, additional sub-elements of the power generation means 70, an LED indicator element and a button element. The secondary detection system includes an ambient light sensor 92, an ambient temperature sensor 94 and a low voltage detector 96. The communication means 60 depicted incorporates a cellular networking system comprising a processing module 64, an internal antenna 66, a SIM card interface 68 and a SIM card, and a wireless local area networking system comprising a processing module 65 and an internal antenna 67. The device 10 may incorporate both a wireless local area network and wireless cellular network connection. The power generation means 70 depicted comprises a solar cell 72, a charge circuit 74, a rechargeable battery 76 and a DC/DC converter 78.

In use, a device in accordance with the first aspect of the invention may obtain a representative measurement of the accumulation of soiling matter on a target surface, by measuring the accumulation of soiling matter of the optical surface of the device. It is preferable that the optical surface is orientated in a similar plane or at a similar angle to the target surface to be monitored. When the device is used to obtain a representative measurement of the accumulation of soiling matter on a solar panel it is preferable that the optical surface has similar optical properties (e g. made of same or similar optical material) to the target surface that is to be monitored.

[0132] In one embodiment, the photosensor incorporates a photoemitter, to emit optical signals, and a photoreceptor, to detect optical signals reflected back to the

22

SUBSTITUTE SHEET (Rule 26) RO/AU photoreceptor by soiling matter in a single photosensor or as a singular component. In an alternative embodiment of the invention the photoemitter and the photoreceptor may be separate components.

[0133] In an embodiment with an internal photoemitter (located within the housing), the photoemitter is arranged to emit optical signals towards the optical surface. The photoreceptor is arranged to detect optical signals that are reflected or redirected by the soiling matter on the optical surface towards the photoreceptor. Preferably, the photoemitter emits infrared light and the photoreceptor is adapted to receive and detect infrared light. The computational unit receives the optical data output from the photoreceptor. The photoemitter and photoreceptor may operate independently of one another.

[0134] Figure 13 depicts a diagram of a device 10 in accordance with a first aspect of the invention detecting soiling matter (depicted as dark circles) on a transparent optical surface 30 using optical signals emitted from an internal photoemitter of the photosensor 40. If there is soiling matter on the optical surface 30 optical signals emitting from the internal photoemitter of the photosensor 40 towards the optical surface 30 will be reflected towards the internal photoreceptor of the photosensor 40. The less soiling matter on the optical surface 30, the more optical signals will pass through the optical surface 30 and the less optical signals will reach the photoreceptor of the photosensor 40.

[0135] In another embodiment, a device according to the present invention may utilise an external photoemitter (located outside of the housing, and which may be a natural light source e.g. sunlight, moonlight) as an alternative optical signal source to an internal photoemitter. In this instance, any internal photoemitter may be inactive or dimmed whilst a photoreceptor operates to receive and detect the optical signals transmitted through the (soiled) optical surface. Preferably, the photoreceptor is adapted to receive and detect the type of optical signals emitted by the external photoemitter. The computational unit receives the optical data output from the

23

SUBSTITUTE SHEET (Rule 26) RO/AU photoreceptor. The photoemitter and photoreceptor may operate independently of one another.

[0136] Figure 14 depicts a diagram of a device 10 in accordance with a first aspect of the invention detecting soiling matter (depicted as dark circles) on the optical surface 30 using optical signals emitted from an external photoemitter, such as the sun. If there is soiling matter on the optical surface 30 optical signals emitting from the external photoemitter onto the optical surface 30 will be reflected away from the internal photoreceptor of the photosensor 40. The less soiling matter on the optical surface 30, the more optical signals will pass through the optical surface 30 and the more optical signals will reach the photoreceptor of the photosensor 40.

[0137] A device according to the present invention may incorporate a combination of internal and external photoemitters. The device may utilise both of these types of photoemitters simultaneously or separately, wherein the device is programmed with specific modes of operation assigned to each type (i.e. a day mode utilising an external photoemitter and a night mode utilising an internal photoemitter).

[0138] A device according to the present invention may be capable of receiving and transmitting data (including optical data in relation to soiling) via the communication means. This data may be related to requests for infonnation, testing or commissioning the device, and other actions within the understanding of a skilled addressee.

[0139] Data and readings from a secondary detection system may form part of the optical data.

[0140] In a further embodiment, an electronic notification is generated when a predetermined value is reached or exceeded, or falls within a predetermined range. The electronic notification may be an alert, a message or an instruction sent via email or a system notification to a software application.

24

SUBSTITUTE SHEET (Rule 26) RO/AU [0141] In an embodiment where the device incorporates multiple photoreceptors the photoreceptors may take measurements si ultaneously. Preferably, when multiple simultaneous measurements are taken the measurements may be averaged and converted into a single data value

[0142] In an embodiment where the device incorporates multiple photoreceptors, an algorithm may be used during data processing to determine discrepancies between the outputs of the photoreceptors and ignore or exclude readings that deviate significantly (i.e. when a reading is outside of a predefined range or amount). Preferably, deviation is measured from the average of the two closest data values. For example, in an embodiment with 6 photoreceptors the readings taken at a particular measurement may be [15%, 16%, 50%, 16%, 16%, 0%] the algorithm may identify that the 50% reading and the 0% are significant discrepancies to the other readings whereas the 15% reading is not. The algorithm will remove these readings leaving [15%, 16%, 16%, 16%J and the remaining readings may be averaged and converted into a single reading of 16%. The acceptable range of deviation may be set as a fixed positive and/or negative value, and/or a scalable positive and or negative value. The acceptable range of deviation may be within one, two, or three standard deviations from the mean. The acceptable range of deviation may be set depending on factors, not limited to: the industrial application, and the type of soiling matter anticipated. Preferably, a user is notified that readings were removed by the algorithm. In the event where two clear groups of values within the acceptable deviation [e.g. 20%, 20%, 40%, 40%, 40%, 20%J the data may be sent as normal and/or a notification may be sent to a user for confmmation.

[0143] Data acquired by the readings of the photoreceptor may be stored internally on the device on an on-board data storage system. This feature allows for the device to acquire and store data without the need for a constant connection back to an external computer (e.g. a server). Preferably, the external computer sends a confimiation transmission to the device when data has been successfully transferred from the device to the external computer. More preferably, the device maintains a log of data that has been successfully transferred and in the event that communication with the

25

SUBSTITUTE SHEET (Rule 26) RO/AU external computer is lost the device is capable of sending any outstanding data when communication is restored. This feature also acts as a means to prevent unintentional data loss due to breakdowns in communication with the external computer, and as a backup in case data is corrupted during transfer. This feature further allows for data to be acquired over a duration (e.g. a day, a week, a month) and sent as a single packet of data to the external computer. The data storage system may incorporate volatile and/or non-volatile memory. Preferably, the data storage system incorporates non volatile memory. Preferably, the data storage system is able to store data for a period of at least one month. Preferably, in the event of the maximum memory of the data storage system being exceeded the device preferentially overwrites existing records/measurements. More preferably, in the event of the maximum memory of the data storage system being exceeded the device preferentially overwrites the oldest records/measurements. Preferably, the device comprises a data processing means and data is stored as processed data percentage values.

[0144] The results of the device detecting soiling on the optical surface can then be interpreted as a reasonably accurate representation of the soiling on the surface that is required to be monitored. Thus, if there is an excessive amount of soiling detected on the device then this should reasonably be the case for the target surface, and an indication or notification that both the device and the target surface should be cleaned can be generated.

[0145] The following paragraphs describe the preferred steps taken to determine the predetermined value or range, calibrate and take measurements with a device in accordance with the first aspect of the invention. Preferably, a record of the calibration settings is stored in the non-volatile memory of the external computer and/or the on-board data storage of the device.

[0146] Preferably, a clean reading is taken for calibration purposes. A clean reading may be taken where the optical surface is determined to be sufficiently free of soiling matter to establish a baseline for later comparison to soiled readings. A clean reading

26

SUBSTITUTE SHEET (Rule 26) RO/AU is preferably taken when there is 0% soiling on the optical surface. The reading establishes the background incident light.

[0147] It is further preferred that a completely soiled reading is taken for calibration purposes. In an embodiment where the device is utilising an internal photoemitter a completely soiled reading is preferably taken by covering the optical surface with a uniform white object or substance (i.e. a ceramic white plate), or more preferably a mirrored object or substance, that 'ould reflect optical signals.

[0148] Preferably, readings are scheduled to be taken during periods where the background incident light is low, such as during the night, and consistent with the background incident light measurement of the clean reading. The background incident light is expected to typically be lowest at midnight, and expected to be lower still at midnight on nights of a new moon.

[0149] Preferably, the target surface and optical surface are of equivalent soiling levels prior to taking measurements or accruing further soiling. For example, both surfaces are clean (0% soiling), or have an equivalent depth and distribution of soiling matter. This is to ensure that readings are representative.

[0150] A predetermined value or range may be established such that when the extent of the soiling is determined to be equal to or beyond the predetermined value, or within the predetermined range, then a notification is generated and sent to an email address or a software application accessible from a mobile device. The predetennined value or range is selected based on the needs of the task the invention is being applied to.

[0151] The predetermined value or range should be established to allow an appropriate amount of time for a notification to be sent and for cleaning to be performed before the soiling reaches a critically undesirable level. For example, a critically undesirable level with regard to soiling matter on a utility pole would be a point at which the level of soiling is determined to be sufficient to form a conductive

27

SUBSTITUTE SHEET (Rule 26) RO/AU path and, thus, pose a significant likelihood of causing a fire. For another example, a critically undesirable level with regard to soiling matter on a photovoltaic panel would be a point at which the level of soiling is determined to be sufficient to prevent the photovoltaic panel from producing a desired amount of power despite given favourable conditions (i.e. a cloudless sunny day). If the critically undesirable level was deemed to be soiling of 50% the notification will be required to be sent well before reaching 50% to allow for time for the cleaning action to take place t hus, a predetermined value of 40% or a predetermined range of 35% to 45% may be appropriate. Cleaning time may be dependent on a range of factors including personnel scheduling, travel time, and required work duration.

[0152] Preferably, readings are compared to the range from clean to completely soiled established in calibration. Alternatively, readings may be compared to the range from clean to the determined critically undesirable level.

[0153] Factors that would inform the selection of the predetennined value or range are, but are not exclusive to: the industrial application, the type of soiling matter anticipated, the projected accumulation rate of soiling, the remoteness of the target surface from cleaning personnel/equipment, and the severity of consequences for the surface being at or beyond the critical level.

[0154] Multiple values or ranges may be set correlating to different notifications. For example: a range of 10% to 20% may indicate, and generate a corresponding notification stating that, some soiling is present ; a range of 21 % to 34% may indicate, and generate a corresponding notification stating that, the accumulation of soiling is significant and cleaning may be required ; a range of 35% to 45% may indicate, and generate a corresponding notification stating that, cleaning is required ; a range of 46% to 49% may indicate, and generate a corresponding notification stating that, cleaning is urgently required, and a range of 50% to 100% may indicate, and generate a corresponding notification stating that, the critical threshold has been exceeded and that cleaning is urgently required.

28

SUBSTITUTE SHEET (Rule 26) RO/AU [0155] In an embodiment where an internal photoemitter is used the predetermined value or range is preferably selected between a 7% to 45% increase in optical signals compared to the clean reading, or more preferably between a 10% to 35% increase in optical signals compared to the clean reading, or even more preferably between a 15% to 25% increase in optical signals compared to the clean reading.

[0156] For example, in an embodiment where the measurement is to be made using an internal photoemitter and the predetermined value is 20%, if the measured optical signals read by the photoreceptor is greater than 20% of the reading of a clean optical surface 30 then an electronic notification for cleaning is generated.

NOTIFICATION GENERATED

[0157] A fully obscured reading (100% soiling) should be close to 0 percent optical signals, or a substantially equivalent reading to a completely soiled calibration reading.

[0158] In an embodiment where an external photoemittcr is used the predetermined value or range is preferably selected between 7% and 45% decrease in optical signals compared to the clean reading, or more preferably between 10% and 35% decrease in optical signals compared to the clean reading, or even more preferably between 15% and 25% decrease in optical signals compared to the clean reading.

[0159] For example, in an embodiment where the measurement is to be made using an external photoemitter (i.e. the sun) and the predetermined value is set at a 20% decrease in optical signals compared to the clean reading, if the measured optical signals read by the photoreceptor is less than 80% of the reading of a clean optical surface 30 then an electronic notification for cleaning is generated.

NOTIFICATION GENERATED

29

SUBSTITUTE SHEET (Rule 26) RO/AU [0160] A fully obscured reading (100% soiling) should be close to 100 percent optical signals, depending on the material properties of the soiling matter (i.e. light absorbance), or a substantially equivalent reading to a completely soiled calibration reading.

[0161] The percentages given for the predetermined value in the above examples are for illustrative purposes only and will vary depending on circumstances such as the environment and expected type of soiling matter.

[0162] Preferably, successive measurements are taken at each reading, and these measurements are averaged and converted to a single data value in order to reduce the likelihood of false readings and noise.

[0163] Preferably, the process for determining that an electronic notification for cleaning is to be generated incorporates functionality to prevent unwanted, repeated notifications from being generated, particularly when the reading is close to the predetermined value or range.

[0164] Figures 15-18 depict an embodiment of a device 10, in accordance with the first aspect of the invention, in use to obtain a representative indication of the soiling matter that has accumulated on a photovoltaic panel. In Figures 15-16 the device 10 is attached to the photovoltaic panel directly via utilisation of a mounting means 90 (in for the form of an articulated clamp). In Figures 17-18 the device 10 is installed adjacent to, but not attached directly to, the photovoltaic panel. In both depictions the device 10 is arranged such that the optical surface 30 is orientated in the same plane and direction as the photovoltaic panel.

[0165] Figure 19 depicts an embodiment of a device 10, in accordance with the first aspect of the invention, in use to obtain a representative indication of the soiling matter that has accumulated on a utility pole. As the conductive path that causes utility pole fires typically forms across a cross arm of the pole, the upwards facing surface of the cross arm would be the most suitable surface to acquire a representative

30

SUBSTITUTE SHEET (Rule 26) RO/AU indication of. Thus, the optical surface 30 is preferably oriented similarly to the upwards facing surface of a cross arm.

[0166] In accordance with a second aspect of the invention there is a system for acquiring representative optical data in relation to soiling of a target surface and notifying a user. The system comprising a detection device, in accordance with a first aspect of the invention, an external computer and a mobile device. The detection device is configured to acquire representative optical data in relation to soiling of the target surface and transmit the optical data to the external computer which is configured to receive, store and or further transmit the optical data to the mobile device.

[0167] The mobile device may be capable of receiving or sending a notification is in communication with the external computer to access or receive the optical data. Incorporating a mobile device into the system may allow for effective identification of device(s) in the field and confirmation of associated readings, especially if multiple detection devices are used in the system. For example, if a reading indicates the device is severely soiled a user with a mobile device may inspect the detection device in the field and discover that the reading may be false via visual inspection of the detection device. In this situation it is beneficial to have access to the data via the mobile device to corroborate findings and/or detect faults.

[0168] Preferably, data transmission is via wireless connection. Removing the necessit for wiring may allow the detection device to be mounted simply and swiftly, and/or allow the mobile device to be used in remote areas.

[0169] The cellular network system may connect to and utilise the infrastructure of a telecommunications (telecomms) network.

[0170] Figure 12 is a block diagram of a system in accordance with the second aspect of the invention in which the embodiment of a first aspect of the invention depicted in Figure 11 forms a system with an external computer (in the form of a backend server)

31

SUBSTITUTE SHEET (Rule 26) RO/AU and a mobile device. In the embodiment depicted, the device 10 is connected to the backend server and the mobile device by a wireless cellular network (via a cell tower) and a local area network (via a local router), with connections to the backend server further utilising a telecommunications network. The mobile device is noted as having an application (app).

[0171] In accordance with a third aspect of the invention a detection device, in accordance with a first aspect of the invention (e g device 10), is used subject to a method for detecting a representative state of soiling of a target surface.

[0172] The method may commence with the steps of selecting the target surface that is required to be monitored and mounting the device on or adjacent to the target surface. Calibration of the device may be undertaken before, during or after being mounted.

[0173] Soiling is allowed to accumulate on an optical surface of the device. At predetermined intervals optical data may be acquired by the device and transmitted to an external computer.

[0174] Preferably, the device accumulates soiling matter on the optical surface similarly to how it settles on the surface that is required to be monitored. Thus, the device would produce a more accurate measurement of the representative state of soiling of a target surface.

[0175] Preferably, the optical surface is orientated such that soiling matter accumulates on the optical surface in a similar manner to the accumulation of soiling matter on the target surface. Thus, the device would produce a more accurate measurement of the representative state of soiling of the representative state of soiling of a target surface.

[0176] The device may be programed to take one or more readings. In an embodiment where multiple readings are taken the readings may be taken either

32

SUBSTITUTE SHEET (Rule 26) RO/AU continuously or intermittently. The readings may be taken at regular predetermined intervals over a set period of time. These intervals may be measured in seconds, minutes, days, weeks, months or years depending on the requirements of the data collection. Readings may be taken intermittently in groups, for example a group of 10 readings taken at 1 minute intervals commencing at noon every fortnight, or a group of 10 readings taken every at hourly intervals commencing at sunrise every first day of the month. Intervals may vary depending on other factors such as seasonal conditions, local sunrise/sunset times or El Nino/La Nina climate patterns

[0177] In an embodiment where the optical surface of the device is transparent or semi-transparent, and a measurement is to be made using an internal photoemitter, a reading may be instigated by activating the photoemitter to emit an optical signal through the optical surface.

[0178] In an embodiment where the device uses an internal photoemitter, if there is soiling matter present on the optical surface optical signals striking the soiling matter would be reflected towards a photoreceptor. The photoreceptor is arranged such as to measure the reflected optical signals. The less soiling on the optical surface the less optical signals would be reflected and therefore reach the photoreceptor.

[0179] In an embodiment where the optical surface of the device is transparent or semi-transparent, and a measurement is to be made using an external photoemitter, a reading may be measured through use of sunlight. A reading may be instigated by activating a photoreceptor at a predetermined time or set of times to receive an optical signal through the optical surface.

[0180] If there is soiling present on the optical surface the soiling would block sunlight from reaching the photoreceptor. The less soiling on the optical surface the more sunlight reaches the photoreceptor.

[0181] In an embodiment of the invention used for detecting a representative state of soiling of photovoltaic panels, the use of the device in performance of a method

33

SUBSTITUTE SHEET (Rule 26) RO/AU according to the third aspect of the invention may produce an indication that a photovoltaic panel is to be cleaned, such that power output from the photovoltaic panel will stay within an optimal range.

[0182] In an embodiment of the invention used for detecting a representative state of soiling of utility poles, the use of the device in performance of a method according to the third aspect of the invention may produce an indication that the utility pole is to be cleaned allowing maintenance to be performed, such that fires may be prevented and the damaged caused by the fires avoided.

[0183] the optical data from a range of measurements may be analysed to chart projected soiling accumulation and thus schedule cleaning and maintenance as a preventative measure.

[0184] In accordance with the fourth aspect of the invention there is a method of detecting soiling on a target surface using a system, according to the second aspect of the invention, to notify a user to the state of soiling of a target surface.

[0185] The method commences with selecting the target surface that is required to be monitored and mounting the device on or adjacent to the target surface.

[0186] Optical data is acquired by measuring optical signals transmitted through or redirected by the optical surface of the device and transmitted to an external computer. Preferably, soiling is allowed to accumulate on the optical surface.

[0187] An electronic notification is sent to the user at a predetermined interval or when the soiling reaches or exceeds a predetermined value or falls within a predetermined range.

[0188] The electronic notification may contain data from a plurality of readings over a predetermined duration or a duration since a previous electronic notification.

34

SUBSTITUTE SHEET (Rule 26) RO/AU [0189] A method in accordance with the fourth aspect of the invention allows for the invention to be more easily suit residential and small commercial applications, by reducing the technical knowledge to install and operate the detection device and system. Running wired communication cables to a detection device or device may be undesirable, expensive or infeasible. Thus, having the means of communication between the detection device and the external computer that is wireless is of distinct benefit. The prevalence of personal mobile devices enables the present invention to be integrated into existing technology and systems easily.

[0190] The system according to the third aspect of the present invention, or the method according to the fourth aspect of the present invention also enables business models to be easily built. For example, a business model in which a designated person or entity is paid to receive and/or monitor the electronic notifications, and organise or take action for the soiled target surface to be cleaned

[0191] Modifications and variations as would be apparent to a skilled addressee are deemed to be within the scope of the present invention.

35

SUBSTITUTE SHEET (Rule 26) RO/AU

Claims

1. A device for detecting soiling on a target surface, comprising: a housing, an optical surface incorporated within the housing to accumulate soiling matter, one or more photosensors arranged to at least receive an optical signal transmitted through or redirected from the optical surface that may be soiled and to acquire optical data in relation to soiling, a communication means to transmit the optical data to an external computer, and a power generation means; wherein power required to operate the device is entirely or substantially provided by the power generation means.

2. The device of claim 1 wherein, the power generation means comprises a photovoltaic cell and a rechargeable battery'.

3. The device of claims 1 or 2 wherein, the device further comprises a mounting means, for mounting the device to a target surface to which the device is to be applied to obtain a representative measurement thereof.

4. The device of claim 3 wherein, the mounting means enables the device to be removably fixed to the target surface.

5. The device of any of the previous claims wherein, the mounting means may be an articulated clamp.

6. The device of any of the previous claims wherein, the photosensor comprises at least a photoreceptor element.

36

SUBSTITUTE SHEET (Rule 26) RO/AU

7. The device of claim 6 wherein, the photosensor comprises a photoemitter element and a photoreceptor element.

8. The device of claim 8 wherein, the device comprises a plurality of photosensors having both a photoemitter element and a photoreceptor element.

9. The device of any of the previous claims wherein, the device further comprises a data processing means to process the optical data acquired by the photosensor(s) to determine the level or extent of soiling, or to transform the optical data into a desired data format for storage and/or communication.

10. The device of claim 9 wherein, the data processing means comprises at least a processing algorithm to process the optical data.

11. The device of claim 9 wherein, the optical data is processed into a collated and communicable format.

12. The device of claim 9 wherein, the data processing means transforms the optical data into a desired data format for storage.

13. The device of claims 9 to 12 wherein, the optical data is processed to exclude specific portions of the data.

14. The device of claims 9 to 13 wherein, the processed optical data is stored as percentage values.

15. The device of claims 9 to 14 wherein, the processed data may be sent by the processing means to the communication means, for further transmission to the external computer.

16. The device of any of the previous claims wherein, the communication means of the device further comprises a cellular networking system.

37

SUBSTITUTE SHEET (Rule 26) RO/AU

17. The device of any of the previous claims wherein, the communication means further comprises a wireless local area networking system.

18. The device of any of the previous claims wherein, the external computer is a server which stores the processed or unprocessed optical data in relation to soiling, or transmits the data to a software application accessible from a mobile device

19. The device of any of the previous claims wherein, when the processed or unprocessed optical data in relation to soiling, reaches or exceeds a predetermined value or falls within a predetermined range, then an electronic notification is generated by and sent from the external computer to an email address or a software application accessible from a mobile device.

20. The device of claim 19 wherein, the electronic notification may be an alert, a message or an instruction.

21. The device of any of the previous claims wherein, the device is easily portable so as to be able to be carried by a single person.

22. The device of any of the previous claims wherein, the device is configured to obtain optical data at regular intervals.

23. The device of any of the previous claims wherein, the device is configured to obtain optical data at intcmiittcntly over the course of at least a month.

24. The device of any of the previous claims wherein, the device is configured to obtain optical data as groups of readings.

25. A system for acquiring representative optical data in relation to soiling of a target surface and notifying a user, the system comprising:

38

SUBSTITUTE SHEET (Rule 26) RO/AU a detection device configured to acquire representative optical data in relation to soiling of the target surface and transmit the optical data, an external computer configured to receive, store and/or further transmit the optical data, and a mobile device in communication with the external computer and accessible by the user; wherein the mobile device is capable of retrieving or receiving the optical data in relation to soiling from the external computer, and/or capable of receiving a notification from the external computer and/or sending a notification to the user when the optical data in relation to soiling reaches or exceeds a predetermined value or falls within a predetermined range.

26. The system of claim 25 wherein, the detection device comprises a data processing means to process the optical data acquired by a photosensor to determine the level or extent of soiling, the data processing means comprising at least a processing algorithm to process the acquired optical data.

27. The system of claim 24 wherein, the photosensor comprises at least a photoreceptor element.

28. The system of claim 25 wherein, the photosensor comprises a photoemitter element and a photoreceptor element.

29. The system of claims 26 to 28 wherein, the data processing means transforms the optical data into a desired data format for storage.

30. The system of claims 25 to 29 wherein, the detection device further comprises a power generation means.

31. The system of claim 30 wherein, the power generation means comprises a photovoltaic cell and a rechargeable battery.

39

SUBSTITUTE SHEET (Rule 26) RO/AU

32. The system of claims 25 to 31 wherein, the detection device further comprises a mounting means, for mounting the detection device to the target surface to which the detection device is to be applied.

33. The system of claim 32 wherein, the mounting means enables the detection device to be removably fixed to the target surface.

34. The system of claims 32 or 33 wherein, the mounting means may be an articulated clamp.

35. The system of claims 25 to 34 wherein, the detection device further comprises a communication means, and the communication means further comprises a cellular networking system.

36. The system of claim 35 wherein, the processed data may be sent by the processing means to the communication means, for further transmission to the external computer.

37. The system of claims 25 to 36 wherein, the detection device further comprises a communication means, and the communication means further comprises a wireless local area networking system.

38. The system of claims 25 to 27 wherein, the detection device further comprises a communication means, and the communication means in the detection device transmits the optical data via a wireless connection.

39. The system of claims 25 to 38 wherein, the external computer is a server which stores the processed or unprocessed optical data and/or transmits the data to a software application accessible from a mobile device.

40. The system of claims 25 to 39 wherein, when the processed or unprocessed optical data in relation to soiling reaches or exceeds a predetermined value or falls

40

SUBSTITUTE SHEET (Rule 26) RO/AU within a predetermined range, then an electronic notification is generated and sent by the external computer to an email address or a software application accessible from the mobile device.

41. The system of claim 40 wherein, electronic notification may be an alert, a message or an instruction.

42. The system of claims 25 to 41 wherein, any of the previous claims wherein, the detection device is easily portable so as to be able to be carried by a single person.

43. The system of claims 25 to 42 wherein, the detection device is configured to obtain optical data at regular intervals.

44. The system of claims 25 to 43 wherein, the detection device is configured to obtain optical data at intermittently over the course of at least a month.

45. The system of claims 25 to 44 wherein, the detection device is configured to obtain optical data as groups of readings.

46. A method of detecting a representative state of soiling of a target surface using a detection device, whereby the method comprises the steps of, mounting the detection device on or adj cent to the target surface, enabling soiling matter to accumulate on an optical surface, acquiring optical data in relation to soiling through the one or more photosensors at a predetermined interval, and transmitting the optical data in relation to soiling to an external computer.

47. The method of claim 46 wherein, the detection device is preferably orientated in the same plane and direction as the target surface.

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48. The method of claims 46 or 47 wherein, the target surface is a photovoltaic panel or a utility pole surface.

49. The method of claim 46 to 48 wherein, the detection device comprises a data processing means to process the optical data acquired by a photosensor to determine the level or extent of soiling, the data processing means comprising at least a processing algorithm to process the acquired optical data.

50. The device of claim 49 wherein, the optical data is processed to exclude specific portions of the data.

51. The device of claims 49 or 50 wherein, the processed optical data is stored as percentage values.

52. The method of claim 51 wherein, the photosensor comprises at least a photoreceptor element.

53. The method of claim 52 wherein, the photosensor comprises a photoemitter element and a photoreceptor element.

54. The method of claims 49 to 53 wherein, the data processing means transforms the optical data into a desired data format for storage.

55. The method of claims 46 or 54 wherein, the detection device further comprises a power generation means.

56. The method of claim 55 wherein, the power generation means comprises a photovoltaic cell and a rechargeable battery.

57. The method of claims 46 to 56 wherein, the detection device further comprises a mounting means, for mounting the detection device to the target surface.

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58. The method of claim 57 wherein, the mounting means enables the detection device to be removably fixed to the target surface.

59. The method of claims 57 or 58 wherein, the mounting means may be an articulated clamp.

60. The method of claims 46 to 59 wherein, the detection device further comprises a communication means, and the communication means further comprises a cellular networking system.

61. The method of claim 60 wherein, the processed data may be sent by the processing means to the communication means, for further transmission to the external computer.

62. The method of claims 46 to 61 wherein, the detection device further comprises a communication means, and the communication means further comprises a wireless local area networking system.

63. The method of claims 46 to 62 wherein, the detection device further comprises a communication means, and the communication means in the detection device transmits the optical data via a wireless connection.

64. The method of claims 46 to 63 wherein, the external computer is a server which stores the processed or unprocessed optical data and/or transmits the data to a software application accessible from a mobile device.

65. The method of claims 46 to 64 wherein, when the processed or unprocessed optical data in relation to soiling reaches or exceeds a predetermined value or falls within a predetermined range, then an electronic notification is generated and sent by the external computer to an email address or a software application accessible from the mobile device.

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66. The method of claim 65 wherein, electronic notification may be an alert, a message or an instruction.

67. The method of claims 46 to 66 wherein, the detection device is easily portable so as to be able to be carried by a single person.

68. The system of claims 46 to 67 wherein, the detection device obtains optical data at regular intervals.

69. The system of claims 46 to 68 wherein, the detection device obtains optical data at mtennittently over the course of at least a month.

70. The system of claims 46 to 69 wherein, the detection device obtains optical data as groups of readings.

71. A method of using a system to notify a user a representative state of soiling of a target surface, whereby the method comprises the steps of, mounting a detection device on or adjacent to a target surface; acquiring optical data in relation to soiling by measuring one or more optical signals transmitted through or redirected by the optical surface that may be soiled; transmitting the optical data to an external computer or a mobile device in communication with the external computer; and sending an electronic notification to the user at a predetermined interval, or when the optical data in relation to soiling reaches or exceeds a predetermined value or falls within a predetermined range.

72. The method of claim 71 wherein, the detection device comprises a data processing means to process the optical data acquired by a photosensor to determine the level or extent of soiling, the data processing means comprising at least a processing algorithm to process the acquired optical data.

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73. The method of claim 72 wherein, the photosensor comprises at least a photoreceptor element.

74. The method of claim 73 wherein, the photosensor comprises a photoemitter element and a photoreceptor element.

75. t he method of claims 72 to 74 wherein, the data processing means transforms the optical data into a desired data format for storage.

76. The method of claims 71 or 75 wherein, the detection device further comprises a power generation means.

77. The method of claim 76 wherein, the power generation means comprises a photovoltaic cell and a rechargeable battery.

78. The method of claims 71 to 75 wherein, the detection device comprises a mounting means to enable the mounting of the detection device to the target surface.

79. The method of claims 77 or 78 wherein, the mounting means may be an articulated clamp.

80. The method of claims 71 to 79 wherein, the detection device further comprises a communication means, and the communication means further comprises a cellular networking system.

81. The method of claim 80 wherein, the processed data may be sent by the processing means to the communication means, for further transmission to the external computer.

82. The method of claims 71 to 81 wherein, the detection device further comprises a communication means, and the communication means further comprises a wireless local area networking system.

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83. The method of claims 71 to 82 wherein, the detection device further comprises a communication means, and the communication means in the detection device transmits the optical data via a wireless connection.

84. The method of claims 71 to 83 wherein, the external computer is a server which stores the processed or unprocessed optical data and/or transmits the data to a software application accessible from a mobile device.

85. The method of claims 71 to 84 wherein, when the processed or unprocessed optical data in relation to soiling reaches or exceeds a predetermined value or falls within a predetermined range, then an electronic notification is generated and sent by the external computer to an email address or a software application accessible from the mobile device.

86. The method of claim 85 wherein, electronic notification may be an alert, a message or an instruction.

87. The method of claims 71 to 86 wherein, the detection device is easily portable so as to be able to be carried by a single person.

88. The system of claims 71 to 87 wherein, the detection device is configured to obtain optical data at regular intervals.

89. The system of claims 71 to 88 wherein, the detection device is configured to obtain optical data at intermittently over the course of at least a month.

90. The system of claims 71 to 89 wherein, the detection device is configured to obtain optical data as groups of readings.

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