Patent Description:
The disclosure herein generally relates to the field of automated surface cleaning systems, and, more particularly, to Unmanned Aerial Vehicle (UAV) Propelled Autonomous Multiplane Cleaning System (UPAMCS).

Autonomous cleaning is in demand for solar panels with varying installation types including roof top solar paneling and floating solar panels spread over wide areas. Clean solar panels improve the efficiency of power generation. Similarly, developments in building and construction has led to high rise buildings, which mostly are covered with glass panes. Cleaning of these inclined glass panes is a regular task performed during building maintenance. Autonomous cleaning is one of the ideal options for cleaning of the above stated surfaces.

Use of efficient methods for the surface cleaning tasks in terms of time, cost and power consumption is critical in automation approaches. One major reason being the sites of cleaning surfaces are generally remote with challenges faced in easy access to power recharging points. Many a times the sites are at remote places. Thus, on-board battery power must be efficiently used. However, conventional autonomous surface cleaners or solar panel cleaners such as autonomous mobile robots or drones used electrically powered motors for movement of a cleaning apparatus across the surface, as well as for activating the cleaning mechanism. Thus, the existing methods are power consuming systems, affecting time and cost of cleaning. One way to assess cleaning efficiency of the surface cleaners can be in terms of ratio of power consumed to area cleaned. Further, in addition to the power consumption aspect, the construct of the cleaning mechanism is critical. Cleaning systems proposed in the art have technical construct limitations in the cleaning mechanisms used, which lead to a lower ratio of power consumed to area cleaned, directly affecting the cleaning efficiency. Document <CIT> discloses an unmanned aerial vehicle device and a system for autonomously cleaning and maintaining a solar photovoltaic panel, wherein the device comprises an unmanned aerial vehicle body, a support and a cleaning assembly, the cleaning assembly comprises a base, a scraper blade, a first driving part, a liquid supply device, a plurality of liquid outlet assemblies, a plurality of dust brushing assemblies, a plurality of universal wheel assemblies and a plurality of fixed connecting shafts, the dust brushing assemblies, the universal wheel assemblies and the fixed connecting shafts are arranged in a one-to-one correspondence manner, the first driving part drives the scraper blade to rotate to a state vertical to the base when the scraper blade works, and the first driving part drives the scraper blade to rotate to a state parallel to the base when the scraper blade does not work; the dust removal subassembly cover is established on corresponding fixed connection axle for clean the solar panel upper surface, and the universal wheel subassembly is connected with corresponding fixed connection axle's the other end, and the unmanned aerial vehicle body passes through the universal wheel subassembly and realizes the removal on solar panel. The invention solves the technical problems that the existing unmanned aerial vehicle suspension air cleaning mode consumes a large amount of electric energy, the cleaning force is insufficient, and the requirement on the accuracy of unmanned aerial vehicle height control is high (Abstract). Document <CIT> discloses a photovoltaic panel cleaning system of a photovoltaic power station, which uses an unmanned aerial vehicle and a cleaning robot, and comprises: workstation, cleaning machines people, unmanned aerial vehicle and photovoltaic board, wherein the workstation includes: the system is provided with an interactive main end, a charging pile and a signal transmitter, wherein the charging pile and the signal transmitter are arranged on the ground, and the charging pile and the signal transmitter are connected with the interactive main end; the photovoltaic panel is arranged on the concrete base through a bracket; cleaning robot links to each other with top unmanned aerial vehicle's unmanned aerial vehicle casing through the main sucking disc that is located the central authorities at robot shell top, and unmanned aerial vehicle carries cleaning robot to move to waiting to wash take off and the descending position on the photovoltaic board. The invention realizes the transfer work of one cleaning robot among a plurality of photovoltaic panels by utilizing the unmanned aerial vehicle, thereby reducing the investment of cleaning equipment. The vacuum pump, the main sucker and the auxiliary sucker are utilized to realize the adsorption and separation of the unmanned aerial vehicle and the cleaning robot; and (<NUM>) adsorbing and separating the cleaning robot from the photovoltaic panel (Abstract). Document <CIT> discloses an unmanned aerial vehicle for cleaning photovoltaic panel, including fixed bolster and photovoltaic board, the photovoltaic board is fixed on the fixed bolster, the top of photovoltaic board is equipped with the unmanned aerial vehicle body, the below of unmanned aerial vehicle body is equipped with support and fixed plate in proper order, the below of fixed plate is equipped with the mobile device, the mobile device passes through fixed plate and support and is connected with unmanned aerial vehicle body fixed, one side of mobile device is equipped with cleans the mechanism, the mobile device is as an organic whole with cleaning the mechanism, unmanned aerial vehicle body starts to drive mobile device and cleans the mechanism and fly, the mobile device starts to drive unmanned aerial vehicle body and cleans the mechanism and move on the photovoltaic board; this novel be used for abluent unmanned aerial vehicle of photovoltaic board can effectually wash the photovoltaic board, not only can be according to the drive of photovoltaic board when wasing, can also change the cleaning object through unmanned aerial vehicle, and overall structure is stable, and the cleaning efficiency is high, is fit for using widely (Abstract). Document <CIT> discloses a kind of photovoltaic plant and glass curtain wall cleaning flight dedusters, including aircraft and operation bench, the lower end of aircraft is provided with clearing apparatus, clearing apparatus includes loading plate, the front end of loading plate is provided with video camera, the two sides of loading plate lower end are provided with lifting assembly straight down, the lower end of lifting assembly is hinged with cleaning framework, the lower end for cleaning framework two sides is provided with the oscillating rod type travel switch matched with lifting assembly, it cleans in framework and is provided with cleaning agency, the side for cleaning framework is provided with installing frame, control mechanism is provided in installing frame, wireless transceiver and driving mechanism, operation bench is communicated by wireless transceiver and control mechanism. The utility model passes through the cooperation of aircraft and clearing apparatus, realizes long-range monitoring and cleaning to solar panel, by the cooperation of lifting assembly and oscillating rod type travel switch, it is adapted to the heeling condition of solar panel (Abstract).

Embodiments of the present disclosure present technological improvements as solutions to one or more of the above-mentioned technical problems recognized by the inventors in conventional systems. In one embodiment, a system, also referred as Unmanned Aerial Vehicle (UAV) Propelled Autonomous Multiplane Cleaning System (UPAMCS), is as defined in the appended claims.

It should be appreciated by those skilled in the art that any block diagrams herein represent conceptual views of illustrative systems and devices embodying the principles of the present subject matter. Similarly, it will be appreciated that any flow charts, flow diagrams, and the like represent various processes which may be substantially represented in computer readable medium and so executed by a computer or processor, whether or not such computer or processor is explicitly shown.

It is intended that the following detailed description be considered as exemplary only, with the true scope being indicated by the following claims.

Surface cleaning systems demand power, time, and cost efficient approaches. Cleaning systems proposed in the art have technical construct limitations in the cleaning mechanisms used, which leads to a lower ratio of power consumed to area cleaned, directly affecting the cleaning efficiency. Embodiments herein provide a system also referred to as an Unmanned Aerial Vehicle (UAV) Propelled Autonomous Multiplane Cleaning System (UPAMCS) for surface cleaning of flat and inclined surfaces. An UAV and Mopping Interface Mechanism (UAV-MIM) connects a UAV to one or more mopping systems comprising an epicyclic gear system, also referred to as planetary gear system, driven moppers with no additional power devices used. A maneuvering mechanism disclosed enables the UAV to propel the mopping systems to reach any geometric shape or inclination. The UPAMCS provides cost, time, and power efficient surface cleaning. The UPAMCS is also equipped with vision cameras and Light Detection and Ranging (LiDAR) for guidance during landing and crawling over surfaces along with additional surface defect detection by performing image processing on the captured images.

Reference numerals of one or more components of the UPAMCS as depicted in the <FIG> are provided in Table <NUM> below for ease of description:.

Irrespective of mode of operation, the mechanism for transfer of energy (forward movement) from the UAV to one or more the mopping system is the same and explained below, with specific design changes, to adapt to the two modes. <FIG> is a three dimensional (<NUM>-D) view of the system <NUM>, also referred to the UPAMCS, in the first mode (UPAMCS1) of operation comprising a single mopping system depicted in a lifting configuration, according to some embodiments of the present disclosure. <FIG> is a three dimensional (<NUM>-D) view of the system <NUM> (UPAMCS), in a second mode of operation (UPAMCS2) comprising a dual mopping system depicted in a lifting configuration, according to some embodiments of the present disclosure.

As depicted in <FIG> and <FIG>, the UAV and Mopping Interface Mechanism (UAV-MIM) <NUM> is mounted on the base frame <NUM> connecting to the UAV <NUM> as a slung load making the UPAMCS portable, which can be easily lifted and placed on surface to be cleaned. Thus, the UAV <NUM>, for example a drone, functions as a primary driving system, wherein the UAV lifts the base frame <NUM> mounted with the mopping systems via the UAV-MIM <NUM> with the lifting configuration. The UAV <NUM> depicted in <FIG> figure is only for illustration. As understood by person having ordinary skill in the art, an appropriate payload UAV can be selected in accordance with the end user requirements and constraints. The UAV-MIM <NUM> becomes vertical with the UAV <NUM> powered for lift off. Once the system <NUM> reaches the destination (surface to be cleaned), the system <NUM> lands gently and operating configuration is activated as depicted in <FIG> and <FIG>. It can be understood that lift off, landing, and setting the UAV-MIM <NUM> into operation mode of interest is controlled via the UAV maneuvering. Thus, once the system <NUM> lands, the UAV <NUM> automatically rotates the UAV-MIM <NUM> to align approximately at <NUM> degrees to the surface panel horizon. This mechanism enables maximum thrust of the UAV <NUM> to be used for driving the mopping system 124A-B. The system <NUM> can be steered by a steering mechanism placed at the driving wheel frame <NUM>. The steering configuration is depicted in 4B and 4C. When the UAV <NUM> propels forward the pair of driving wheels <NUM> (at rear end of base frame <NUM>) and the driven wheels 114A-C connected in the front end, the LHS and the RHS of the base frame <NUM> are moved by friction and the system <NUM> starts moving in either forward or backward, depending on the push direction of the drone with help of the steering mechanism.

<FIG> depict structural mechanism of a plurality of components of the base frame <NUM> that transfer push from the UAV <NUM> to drive for one or more mopping systems, according to some embodiments of the present disclosure. As depicted in 3D view of <FIG>, the driving wheel frame <NUM> is connected to a rear end of the base frame <NUM>. The pair of driving wheels <NUM> is attached to a lower side (or bottom side) of the driving wheel frame <NUM> at the rear end. The worm wheel 116B is attached to a driver wheel axle of the pair of driving wheels <NUM>, which in turn drives the worm 116A about a vertical axis. As depicted in the 3D view of <FIG>, the driver pulley <NUM> fixed at a top end of the worm 116A, wherein one or more driven pulley belts 120A-B transmit drive from the driver pulley <NUM> to one or more driven pulleys 122A-B further connected to one or more mopping systems 124A-B.

Thus, the system <NUM> provides two embodiments, the single mopping system and dual mopping system. The choice of mode to be used is dependent on area of the surface of interest. For example, for a smaller area the single mopping system is a preferred choice at it reduces the payload of the UAV <NUM> to half and hence the cost.

<FIG> depict the mechanism of the mopping system <NUM> connected to the base frame <NUM> of the UPAMCS <NUM>, according to some embodiments of the present disclosure. Each mopping system 124A-B has similar (or identical) mechanism for cleaning. As depicted in the 3D view of <FIG>, top view of in <FIG> and sideview of <FIG>, the mopping system <NUM> includes the set of drive arms 126A driven by the driven pulley 120A attached further driving an epicyclic or planetary gear system. The planetary gear system comprises an annular gear wheel 130A fixed to the lower side of the base frame <NUM>, a set of planet gear wheels 132A each connected to the drive arm among the set of drive arms 126A. The set of planet gear wheels 132A are meshed between fixed internal teeth of the annular gear wheel 130A and the sun gear wheel 128A, while each of the drive arm rotates the set of planet gear wheels 132A which in turn rotates the sun gear wheel 128A and a mopping material <NUM> fixed to a bottom side of the sun gear wheel 128A and the set of planet gear wheels 132A.

The UPAMCS <NUM> is equipped with the cleaning fluid distribution network <NUM> attached to the base frame <NUM>, which can operate differently for to address requirements of cleaning fluid spaying for an inclined surface and a flat surface. Examples of inclined surfaces include vertically mounted (<NUM> degrees) glass panes or angularly mounted glass panes. The UAV <NUM> with UAV-MIM <NUM> can easily maneuver the moping systems at any angle with irregular shape surface. Examples of flat surfaces include floating or roof top solar panels and the like. The cleaning fluid distribution network <NUM> comprises (i) an inclined surface cleaning mechanism for spraying the cleaning fluid in an upward direction, and (ii) a flat surface cleaning mechanism for spraying the cleaning fluid in a downward direction for a surface to be cleaned below the one or more mopping systems 124A-B. <FIG> depicts <NUM>-D view of construction of the cleaning fluid distribution network <NUM> mounted on the base frame <NUM> for cleaning a flat surface and an inclined surface during the first mode of operation (UPAMCS1), according to some embodiments of the present disclosure. <FIG> depicts construction of the cleaning fluid distribution network <NUM> mounted on the base frame for cleaning the flat surface and the inclined surface during the second mode of operation (UPAMCS2), according to some embodiments of the present disclosure.

As depicted in the <NUM>-D view of <FIG> and <FIG>, the inclined surface cleaning mechanism comprises the plurality of X-type cleaning fluid tanks <NUM> (elevated with head difference) and a plurality of Y-type nozzles <NUM> (in line with plane of inclined surface to be cleaned), which are electrically activated using the electrical nozzle actuation system 142A-B on receiving signals from the proximity sensors 144A-B and the vision cameras 138A-D. Once the Y-type nozzles <NUM> that are placed parallel to the inclined plane of the surface to be cleaned are activated, the cleaning fluid is sprayed via the piping network <NUM> to clean the inclined surface using one or more cylindrical surface cleaning rollers <NUM>. The cylindrical surface cleaning rollers <NUM> are a single unit in <FIG> for single mopping system for the first mode UPAMCS1, while the <FIG> depicts a split design for dual mopping system aligned in front of each mopping system 132A-B.

As depicted in <FIG> and <FIG>, the flat surface cleaning mechanism comprises a plurality of A-type cleaning fluid tanks <NUM> (at base frame level with head difference) and a plurality of B-type nozzles <NUM> (directed downwards towards flat surface to be cleaned), which are electrically activated using the electrical nozzle actuation system 142A-B on receiving signals from the proximity sensors 144A-B and the vision cameras 138A-D. Once the B-type nozzles (<NUM>) that face towards the mopping system facing the surface to be cleaned are activated, the cleaning fluid is sprayed via the piping network <NUM> to clean the flat surface using one or more cylindrical surface cleaning rollers <NUM> and the one or more mopping systems 124A-B. The flow of the cleaning fluid is ensured by placing the cleaning fluid tanks to allow gravity flow.

UPAMCS operation: The UAV <NUM> is equipped with landing and take-off configurations, wherein the UAV-MIM <NUM> allows the UAV <NUM> to land and take-off vertically. A drive configuration of the UPAMCS <NUM> activated after landing on the surface enables utilizing a propulsive power of the UAV <NUM> to maximum for pushing the pair of driving wheel <NUM> and the driven wheels 114A-C using friction, wherein the pair of driving wheels <NUM> at the rear end of the base frame <NUM>, and the driven wheels 114A-C attached to each of a front end, a Left Hand Side (LHS) and a Right Hand Side (RHS) of the base frame <NUM> push the UPAMCS <NUM> forward over the surface to be cleaned. The cleaning fluid distribution network <NUM> is activated as soon as the UPAMCS <NUM> lands and drives forward, spraying the cleaning fluid on the surface enabling the mopping system 124A-B to cleanse. One or more cylindrical surface cleaning rollers <NUM> installed in the front of the base frame <NUM> and supported at (i) the LHS, a middle side and the RHS of the UPAMCS base frame <NUM> for a two cylindrical surface cleaning rollers configuration, and (ii) at the LHS and the RHS for a single cylindrical surface cleaning roller configuration. The brushes are free to rotate about central axles. The electrical nozzle activation system 142A-B and the proximity sensor 144A-B can be controlled via on-board processing by the UAV <NUM> in accordance with the current UPAMCS configuration.

<FIG> illustrates a visual based navigation system enabled by LiDARS 140A-D and one or more vision cameras 138A-D, each placed each end of the of the base frame <NUM>. The visual information and LiDAR points captured by a visual based navigation system can be processed on-board by the UAV <NUM> enabling automatically and dynamically monitoring and tracking of the action of UPAMCS <NUM> over the surface to be cleaned. This also enables inspection of the surface. The processed information can be communicated to a central processing unit by the UAV <NUM> for further action to be initiated such as triggering damage alert, notifying cleaning task initiation or completion and so on to a remote administrator In an embodiment, additional tactile or pressure sensors may be implemented for controlling the impact of the system (<NUM>) while landing, moving or in contact with surface to be cleaned, specifically for impact sensitive surfaces such as solar panels. In an embodiment the system may be equipped with a single LiDAR and placed at any one of the front end, rear end, LHS and RHS of the base frame <NUM>, such that the single LiDAR provides the necessary views for navigation and control.

The mopping system <NUM> works under three configurations comprising:.

<FIG> is a schematic depicting inclined surface cleaning mechanism by maintaining with the UAV in the lift configuration, wherein the system <NUM> moves up and down with the cylindrical surface cleaning rollers <NUM> pressing against the inclined surface such as a windowpane.

Provided below is an illustrative 'cleaning time' calculation of the system <NUM>.

The scope of the subject matter embodiments is defined by the claims.

Also, the words "comprising," "having," "containing," and "including," and other similar forms are intended to be equivalent in meaning and be open ended in that an item or items following any one of these words is not meant to be an exhaustive listing of such item or items or meant to be limited to only the listed item or items.

Claim 1:
An Unmanned Aerial Vehicle (UAV) Propelled Autonomous Multiplane Cleaning System (UPAMCS) (<NUM>), comprising:
a UAV (<NUM>), a UAV and Mopping Interface Mechanism (UAV-MIM) (<NUM>), a base frame (<NUM>), and mopping systems (124A-B), wherein the UAV-MIM (<NUM>) is mounted on the base frame (<NUM>) of the UPAMCS connecting to the UAV (<NUM>) as a slung load, wherein the UAV (<NUM>) lifts the base frame (<NUM>) mounted with mopping systems (124A-B) via the UAV-MIM (<NUM>);
a driving wheel frame (<NUM>) connected to a rear end of the base frame (<NUM>);
a pair of driving wheels (<NUM>) attached to a lower side of the driving wheel frame (<NUM>) at the rear end, a worm (116A) and a worm wheel (116B), wherein the worm wheel (116B) is attached to a driver wheel axle of the pair of driving wheels (<NUM>), which in turn drives the worm (116A) about a vertical axis;
a driver pulley (<NUM>) fixed at a top end of the worm (116A), wherein one or more driven pulley belts (120A-B) transmit drive from the driver pulley (<NUM>) to one or more driven pulleys (122A-B) connecting one or more mopping systems (124A-B),
each mopping system (124A) comprising:
a set of drive arms (126A) driven by the driven pulley (122A) attached;
an annular gear wheel (130A) fixed to the lower side of the base frame (<NUM>); and
a set of planet gear wheels (132A), each planet gear wheel from the set of planet gear wheels (132A) is connected to a drive arm among the set of drive arms (126A), wherein the set of planet gear wheels (132A) is meshed between fixed internal teeth of the annular gear wheel (130A) and a sun gear wheel (128A), wherein each of the drive arm rotates the set of planet gear wheels (132A) which in turn rotate the sun gear wheel (128A) and a mopping material (<NUM>) fixed to a bottom side of the sun gear wheel (128A) and the set of planet gear wheels (132A); and
a cleaning fluid distribution network (<NUM>) attached to the base frame (<NUM>) comprising (i) an inclined surface cleaning mechanism for spraying cleaning fluid in an upward direction and (ii) a flat surface cleaning mechanism for spraying the cleaning fluid in a downward direction for a surface to be cleaned below the one or more mopping systems (124A-B).