Claims:WE CLAIM:

1. An unmanned vehicle (230) configured to float over a liquid surface for monitoring liquid quality, the unmanned vehicle (230) comprising:
a robotic assembly (240) comprising:
an arm (242) having a plurality of links (244) movable with respect to each other to extend and retract the arm (242); and
one or more sensors (248) mounted on the arm (242), wherein the one or more sensors (248) are configured to collect data related to the liquid quality; and
a controller (250) communicatively coupled with the robotic assembly (240) and configured to operate the arm (242) of the robotic assembly (240) from a retracted position to an extended position and vice-versa for collecting the data related to the liquid quality.

2. The unmanned vehicle (230) as claimed in claim 1, wherein:
the robotic assembly (240) is placed on a surface of the unmanned vehicle (230); or
the unmanned vehicle (230) comprises an opening at a bottom side thereof, and the robotic assembly (240) is disposed within a space defined within the opening.

3. The unmanned vehicle (230) as claimed in claim 1, wherein the one or more sensors (248) are configured to collect the data related to the liquid quality at one or more depth levels in real-time while the controller (250) extends or retracts the arm (242) of the robotic assembly (240) into the liquid.

4. The unmanned vehicle (230) as claimed in claim 1, wherein the robotic assembly (240) further comprises at least one depth sensor for measuring a liquid depth, and wherein the controller (250) is configured to extend the arm (242) of the robotic assembly (240) into the liquid up to the liquid depth.

5. The unmanned vehicle (230) as claimed in claim 1, wherein the data comprises information pertaining to pH, conductivity, dissolved oxygen, turbidity, chloride, and temperature of the liquid.

6. The unmanned vehicle (230) as claimed in claim 1, wherein the controller (250) is further configured to communicate with a navigation system for navigating the unmanned vehicle (230) within a pre-defined area to measure the liquid quality at different locations.

7. A method (400) of monitoring liquid quality using an unmanned vehicle (230) configured to float over a liquid surface, the method (400) comprising:
providing (402) a robotic assembly (240) comprising:
an arm (242) having a plurality of links (244) movable with respect to each other to extend and retract the arm (242); and
one or more sensors (248) mounted on the arm (242), wherein the one or more sensors (248) are configured to collect data related to the liquid quality; and
operating (404), by a controller (250), the arm (242) of the robotic assembly (240) from a retracted position to an extended position and vice-versa for collecting the data related to the liquid quality.

8. The method as claimed in claim 7, further comprising:
collecting the data related to the liquid quality at one or more depth levels in real-time while operating the arm (242) of the robotic assembly (240), from the retracted position to the extended position and vice-versa, into the liquid.

9. The method as claimed in claim 7, further comprising:
measuring, using at least one depth sensor, a liquid depth; and
extending the arm (242) of the robotic assembly (240) into the liquid up to the liquid depth.
 

10. The method as claimed in claim 7, further comprising:
communicating with a navigation system for navigating the unmanned vehicle (230) within a pre-defined area to measure the liquid quality at different locations.
, Description:TECHNICAL FIELD
[001] The present disclosure relates generally to liquid quality monitoring, and more particularly to liquid quality monitoring using an unmanned vehicle.

BACKGROUND
[002] Due to increasing industrialization and population growth, the quality of water bodies is deteriorating at an alarming rate. Poor quality water is harmful not only for aquatic life but for humans as well. To protect ecosystem and public health from poor quality water, it becomes important to monitor the water quality. Further, in industries various types of liquids are used either during manufacturing or as an end-product. To determine or improve quality of the end product and to minimize production costs, monitoring quality of such liquids is a crucial step.

[003] Conventionally the water or liquid quality monitoring is carried out manually. Manual techniques involve collecting samples of liquid in bottles from liquid source and then manually analyzing the collected samples by experts in laboratory for measuring various parameters related to liquid quality including pH, dissolved oxygen, turbidity etc. However, this approach of liquid quality monitoring is expensive, time consuming, prone to human errors. Also, it requires a lot of manual efforts e.g., in collecting samples and analyzing the collected samples. Further, if the liquid sources are longer in the span, it becomes difficult to manually collect liquid samples at different locations. For example, for a lake or river, it becomes difficult to manually collect liquid samples at different locations across the entire span of the river or the lake Additionally, real-time monitoring of liquid is not possible using the manual techniques. Moreover, collecting samples of liquid in hazardous environments is a challenging task.

[004] Therefore, there is a need for techniques which can accurately monitor the quality of liquid in real time without requiring manual efforts. There is a further need for techniques which can monitor liquid quality in all types of environments and liquid sources.
 
SUMMARY OF THE INVENTION
[005] In an embodiment, an unmanned vehicle for measuring liquid quality is disclosed. The unmanned vehicle is configured to float over a liquid surface and comprises at least a robotic assembly and a controller communicatively coupled with the robotic assembly. The robotic assembly comprises an arm having a plurality of links movable with respect to each other to extend and retract the arm; and one or more sensors mounted at a distal end of the arm. The one or more sensors are configured to collect data related to the liquid quality. The controller is configured to operate the arm of the robotic assembly from a retracted position to an extended position and vice-versa for collecting the data related to the liquid quality.

[006] In another embodiment, a method for measuring liquid quality is disclosed. The method makes use of an unmanned vehicle which is configured to float over a liquid surface. The method comprises providing a robotic assembly comprising an arm having a plurality of links movable with respect to each other to extend and retract the arm; and one or more sensors mounted at a distal end of the arm. The one or more sensors are configured to collect data related to the liquid quality. The method further comprises operating, using a controller, the arm of the robotic assembly from a retracted position to an extended position and vice-versa for collecting the data related to the liquid quality.

BRIEF DESCRIPTION OF THE DRAWINGS
[007] The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate exemplary embodiments and, together with the description, serve to explain the disclosed principles.

[008] Figure 1 illustrates a conventional system 100 for monitoring liquid quality;

[009] Figure 2(a) and 2(b) illustrate a liquid quality monitoring system 200, in accordance with an embodiment of the present disclosure;

[010] Figure 3 illustrate an exemplary view 300 of a robotic assembly 240 for monitoring liquid quality, in accordance with some embodiments of the present disclosure;

[011] Figure 4 illustrates a method 400 for monitoring liquid quality using an unmanned vehicle, in accordance with an embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE DRAWINGS
[012] Exemplary embodiments are described with reference to the accompanying drawings. Wherever convenient, the same reference numbers are used throughout the drawings to refer to the same or like parts. While examples and features of disclosed principles are described herein, modifications, adaptations, and other implementations are possible without departing from the spirit and scope of the disclosed embodiments. It is intended that the following detailed description be considered as exemplary only, with the true scope and spirit being indicated by the following claims. In the following description, well known functions or constructions are not described in detail since they would obscure the description with unnecessary detail.

[013] The present disclosure relates to monitoring quality of liquid using an unmanned vehicle. For the sake of simplicity and explanation, the liquid may be considered as water. However, the present disclosure is not limited thereto and in general, the proposed techniques of liquid quality monitoring are equally applicable for monitoring quality of any liquid.

[014] Polluted water is harmful for both aquatic life and humans. Hence, monitoring real-time quality of water is important for controlling water pollution and for protecting public health (e.g., by ensuring that good quality drinking water is supplied to public). Traditional water quality monitoring systems generally rely on manually collecting samples which is time consuming and costly. Nowadays, wireless sensors based nodal networks are used for monitoring water quality, as shown in Figure 1.

[015] Referring now to Figure 1, which illustrates a traditional technique, in which, a nodal network system 100 is used for monitoring quality of liquid. The system 100 comprises a monitoring device 110 and a plurality of sensors 130-1, 130-2, 130-2, 130-4 (collectively represented by reference numeral 130) planted deep inside a water body/liquid source 120 (e.g., lake or river). The sensors 130 are mounted manually and their position inside the water body 120 is fixed. The sensors 130 collect data related to the quality of water and send the collected data to the monitoring device 110. The monitoring device 110 may then measure the water quality based on the received data.

[016] Though approach does not require the water samples to be manually collected and then analyzed in laboratory for monitoring water quality, still it has some drawbacks. For example, the sensors 130 are very expensive and more importantly their maintenance is very difficult because the sensors 130 are remotely located i.e. they are planted deep inside the river or the lake. The data collected by any sensor may be wrong e.g., if an aquatic animal like huge fish hits the sensor. The sensors 130 may get easily damaged during natural disasters or by aquatic animals. Further, this solution is not effective in industries where the quality of the chemicals/liquid materials are to be monitored because the sensors may get easily damaged by chemicals and their replacement and repairing deep inside the chemicals may be a challenging task.

[017] Due to the above-mentioned challenges, water quality monitoring is still regarded as a complex problem and it is desirable to develop efficient techniques of water quality monitoring. To overcome these and other challenges, the present disclosure discloses an unmanned vehicle for measuring water quality. The unmanned vehicle is configured to float over a surface of the liquid and comprises a robotic assembly controlled by a controller. The robotic assembly comprises an arm having a plurality of links movable with respect to each other to extend and retract the arm inside the water. The robotic assembly also comprises one or more sensors mounted on the arm for collecting data related to the liquid quality at one or more depth levels in real-time while the arm extends or retracts into the liquid.

[018] Referring now to Figures 2(a), which illustrates the disclosed water quality monitoring system 200-1 for monitoring water quality of a water body 120, in accordance with some embodiments of the present disclosure. The water quality monitoring system 200-1 may comprise an unmanned vehicle 230 which is configured to float over a top surface 120-1 of the water body 120. The water quality monitoring system 200-1 may further comprise a remote device 210 communicatively coupled with the unmanned vehicle 230 via at least one network 220.

[019] The at least one network 220 may comprise a data network such as, but not restricted to, the Internet, Local Area Network (LAN), Wide Area Network (WAN), Metropolitan Area Network (MAN), etc. In certain embodiments, the network may include a wireless network, such as, but not restricted to, a cellular network and may employ various technologies including Enhanced Data rates for Global Evolution (EDGE), General Packet Radio Service (GPRS), Global System for Mobile Communications (GSM), Internet protocol Multimedia Subsystem (IMS), Universal Mobile Telecommunications System (UMTS) etc. In one embodiment, the network 220 may include or otherwise cover networks or subnetworks, each of which may include, for example, a wireless data pathway. In one embodiment, the network may comprise Bluetooth and Wireless Local Area Network (WLAN) etc.

[020] In one non-limiting embodiment, the unmanned vehicle 230 may comprise a robotic assembly 240 which may be used for collecting data related to the water quality. The robotic assembly 240 may comprise a robotic arm which may be extended into the liquid and retracted out of the liquid, as shown in Figure 2(b). Referring now to Figure 2(b), which shows the disclosed water monitoring system 200-2 with the robotic arm 242 extended into the water body 120, in accordance with some embodiments of the present disclosure. The robotic arm 242 is configured to move between a default/retracted position and an extended position. The water monitoring systems 200-1 and 200-2 may be collectively represented by reference numeral 200. The unmanned vehicle 230 may further comprise a controller 250 communicatively coupled with the robotic assembly 240 and configured to control the movement of the robotic assembly 240. The unmanned vehicle 230 may collect data related to the water quality using the robotic assembly 240 and send the collected data to the remote device 210 which may then present/convert the collected data in a human understandable format (e.g., the remote device may generate one or more reports 260 showing the water quality).

[021] In one non-limiting embodiment, the robotic assembly 240 may be disposed on a bottom side 234 of the unmanned vehicle 230. At least some part of the bottom side 234 of the unmanned vehicle 230 may be in contact with the top surface 120-1 of the water body 120, whereas a top side 232 of the unmanned vehicle 230 may be facing the sky. In one non-limiting embodiment, the unmanned vehicle 230 may comprise an opening or open cavity 236 of any shape at the bottom side 234 thereof and the robotic assembly 240 may be disposed within a space defined inside the unmanned vehicle 230 in such a manner that a robotic arm 242 of the robotic assembly 240 is configured to pass through the cavity towards the water surface 120-1. The robotic assembly 240 may be removably mounted in such a manner that mounting the robotic assembly 240 inside the cavity 236 does not require use of any special tools. In one non-limiting embodiment, the robotic assembly 240 may be removably attached on any side or surface of the unmanned vehicle 230.

[022] The robotic arm 242 of the robotic assembly 240 may be made up of a plurality of links 244-1, …, 244-N (collectively represented by reference numeral 244). The plurality of links 244 may be movable with respect to each other to extend and retract the robotic arm 242 for measuring the water quality from the top water surface 120-1 till the bottom water surface 120-2. Each of the plurality of links may have the same length and may have a circular, rectangular, or polygonal shaped cross-section, but not limited thereto. The plurality of links 244 may facilitate a linear movement of the robotic arm 242 in the vertical direction when the robotic arm 242 is extended into the water. The amount of the linear movement of the robotic arm 242 between a default position and the extended position may depend on the depth of the water body 120. As will be understood, the amount of linear movement of robotic arm 242 between the default position and the extended position must be sufficient to measure water quality till the bottom water surface 120-2 of the water body 120.

[023] The size or area of the cavity 236 defined within the unmanned vehicle 230 may vary depending on one or more of: a size of the robotic assembly 240, a length of each link 244, and a depth of the water body 120 (e.g., more the depth of the water body 120, more is the number of links, and hence larger is the cavity size required to accommodate the links).

[024] In one non-limiting embodiment, the robotic assembly 240 may comprise a plurality of sensor assemblies 246, 248 disposed on the robotic arm 242 in such a manner that each link comprises at least one sensor assembly, as shown in Figure 2(b). The plurality of sensor assemblies 246, 248 may comprise a depth sensor assembly 246 and at least one water quality sensor assembly 248. In one embodiment, the at least one depth sensor assembly 246 may be mounted at the distal end of the robotic arm 242. The plurality of sensor assemblies 246, 248 may be communicatively coupled with the controller 250 via wired and/or wireless pathways.

[025] The at least one depth sensor assembly 246 may comprise one or more sensors for measuring the depth of the water body 120. The one or more sensors may include ultrasonic sensor, radar sensor, pressure sensor, and sonar sensor, but not limited thereto. The ultrasonic sensor may measure the depth of the water body 120 using ultrasonic sound waves. The ultrasonic sensor requires a transmitter and a receiver (or a single transceiver). The transmitter may send an ultrasonic pulse from the top water surface 120-1 which travels through the water and bounces back from the bottom water surface 120-2 and is received by the receiver. By calculating the travel time, the depth of the water body (i.e., the distance of the bottom water surface 120-2 from the top water surface 120-1) can be calculated.

[026] Each of the plurality of links 244 may comprise at least one water quality sensor assembly 248. A water quality sensor assembly 248 may comprises one or more sensors configured to measure various parameters related to chemical, physical, and biological properties of water. These parameters may comprise for example - pH, conductivity, temperature, dissolved oxygen, turbidity, chlorine, suspended solids, but not limited thereto. The one or more sensors may include pH sensor, conductivity sensor, residual chlorine sensor, turbidity sensor, oxidation-reduction potential (ORP) sensor, Chemical Oxygen Demand (COD) sensor, Biological Oxygen Demand (BOD) sensor, Ammonia Nitrogen Ion sensor, temperature sensor, but not limited thereto.

[027] The pH sensor measures the level of pH in water by measuring the activity of the hydrogen ions present in the water. The pH sensor measures acidity or alkalinity of water on a range of 0-14. A pH of less than 7 indicate acidity whereas a pH of more than 7 indicates alkalinity of water. A conductivity sensor measures the ability of water to conduct an electrical current. Conductivity depends on concentration of ions in a water sample. A chlorine sensor is configured to measure amount of residual chlorine, chlorine dioxide, and ozone in a water sample. A turbidity sensor measures the amount of light that is scattered by suspended solids in the water sample. The turbidity sensor operates on the principle that when light is passed through the water sample, the amount of light transmitted through the sample is dependent on the amount of suspended solids present in the water sample.

[028] The ORP sensor measures activity of oxidizers and reducers in a water sample. In other words, it measures the ability of the water body 120 to clean itself by breaking down waste products (e.g., dead plants and animals, and other contaminants). The BOD sensor measure the Biochemical oxygen demand (BOD) which is the amount of dissolved oxygen consumed by biological organisms. The COD sensor measure chemical oxygen demand (COD) which is the amount of oxygen consumed during breaking down of organic material and during oxidation of present inorganic material. The ammonia nitrogen sensor is used to measure the ammonia nitrogen content present in water. The water temperature sensor may measure the temperature of a water sample and can detect an unusual rise or fall in temperature.

[029] In one non-limiting embodiment, the unmanned vehicle 230 may further comprise a memory 252, an energy source 254, one or more motor, one or more interfaces, and a transceiver communicatively coupled with the controller 250. The energy source 254 may be configured to supply power to various components of the unmanned vehicle 230 including, but not limited to, controller 250, the one or more motor, the plurality of sensor assemblies 246, 248 etc. The energy source 254 may be a solar powered energy source or a rechargeable battery powered energy source, but not limited thereto.

[030] The transceiver may be used for transmitting and receiving signals and other data/information within the unmanned vehicle 230 or with other devices communicatively coupled with the unmanned vehicle 230. The transceiver may comprise antennas for transmitting and receiving the signals and other data/information. The memory 252 may comprise commands, sensor data, navigation data etc. The memory 252 may further store one or more instructions executable by the controller 250. The memory 252 may include a Random-Access Memory (RAM) unit and/or a non-volatile memory unit such as a Read Only Memory (ROM), optical disc drive, magnetic disc drive, flash memory, Electrically Erasable Read Only Memory (EEPROM), a memory space on a server or cloud and so forth.

[031] In one non-limiting embodiment, the controller 250 may utilize location services or navigation system provided by external entities for navigating the unmanned vehicle 230 along a predefined route and/or within a predefined area as defined by an operator/user operating/using the unmanned vehicle 230. For example, the controller 250 may be configured to communicate with Global Positioning System (GPS) for navigating the unmanned vehicle 230 within the predefined area (e.g., within a lake) and/or the predefined route (e.g., along a river) defined by GPS coordinates. The unmanned vehicle 230 is designed in such a manner that it can withstand turbulence and any other natural disturbance. Following paragraphs now describe the working of the unmanned vehicle 230 for measuring the water quality.

[032] Initially, an operator programs the unmanned vehicle 230 by providing location information or GPS co-ordinates of the water body 120 whose water quality is to be monitored. When the unmanned vehicle 230 is put on surface 120-1 of the water body 120, the controller 250 starts operating the unmanned vehicle 230. The controller 250 may be configured to control the movement of the unmanned vehicle 230 and the robotic arm 242. When the unmanned vehicle 230 is at a particular point within the predefined area or along the predefined route, the controller 250 may collect data from the depth sensor assembly 246 to determine the depth of the water body 120. After determining the depth of the water body 120, the controller 250 may linearly open the links to extend the robotic arm 242 towards the bottom water surface 120-2 of the water body 120. It may be noted that in order to protect the robotic arm 242 from being damaged due to obstacles present at the bottom 120-2, the controller 250 may extend the robotic arm 242 up to a distance which is less than the actual depth of the water body 120 (i.e., the controller ensures that the depth sensor assembly 246 does not touch the bottom of the water body 120 and there is some space between the bottom surface 120-2 and the depth sensor assembly 246), as shown in Figure 2(b).

[033] In one non-limiting embodiment, the controller 250 may collect and store data from the various water quality sensor assemblies 248 disposed on the links 244 which are inside water. Each sensor of the water quality sensor assemblies 248 and each link of the plurality of links 244 may have their unique identities and the controller 250 may store a mapping indicating which sensor assembly is mounted on which link and at what length. This mappings may help in determining the water quality at a particular depth inside the water body 120. This is explained by way of an example, as follows:

[034] Consider that:
Depth of water body 120 as estimated by the depth sensor assembly 246 is: 3m.
Total number of links in the robotic arm= 50 (L1 to L50)
Length of each link: 90cm
Assuming that each link comprises two water quality sensor assemblies mounted at 30cm and 60cm from one end of the link.
Depending on the depth of the water source i.e., 3m, the controller 250 may extend three links L1, L2, and L3 into the water towards the bottom water surface 120-2, as shown in Figure 3. In Figure 3, for the sake of brevity, the depth sensor assembly 246 has been represented by ‘D’, the links 244 have been represented by ‘L1, L2, L3…’; and water quality sensor assemblies 248 have been represented by ‘S1, S2, S3….’
Based on the mapping, the controller 250 knows the exact position of each sensor on the robotic arm 242. Consider that the distance between the depth sensor assembly D and the bottom water surface 120-2 is 60cm (this can be determined by taking the data from depth sensor assembly). Now, using following calculations, the controller 250 may determine that the distance of S1 from top water surface 120-1 is:
D1= depth of water source - distance between the depth sensor assembly D and the bottom water surface – distance of S1 from distal end of robotic arm
i.e., D1= 3*100 - 60 - 30= 2.1m
Similarly, the distance of S2 from top water surface 120-1 is:
D2= 300-60-60= 1.8m
Similarly, the distance of S3 from top water surface 120-1 is:
D3= 300-60-90-30= 1.2m

[035] In this manner, the controller 250 may determine the depth of each water quality sensor assembly 248 from the top water surface 120-1. When the controller 250 collects data from sensor assembly S1, it maps this data with the depth of sensor assembly S1 and stores this mapping in the memory. Using similar approach, the controller 250 may collect the data related to the water quality from all sensor assemblies. It may be noted here that the unmanned vehicle 230 collects the data related to the liquid quality from surface till depth levels instead of collecting water samples.

[036] After a lapse of predetermined time duration, the controller 250 may retract the robotic arm 242 from the water body by linearly retracting the extended links. The predetermined time interval is determined such that the all water quality sensor assemblies 248 which are inside the water are able to provide the data to the controller 250 related to the water quality within the predetermined time interval. In one non-limiting embodiment, the controller 250 may utilize a motorized mechanism for extending and retracting the robotic arm 242. The controller 250 may then navigate the unmanned vehicle 230 to another location for collecting data related to the water quality. In this manner, the unmanned vehicle 230 keeps roaming on the water surface while collecting the data related to the water quality.

[037] In one non-limiting embodiment, if the data from multiple sensor assemblies has same value, the controller 250 may store only a single value corresponding to the redundant values. In one aspect, it may be noted that the robotic assembly 240 is mounted in such a way that at least one of the water quality sensor assembly 248 and depth sensor 246 are always in contact with the top surface 120-1, as shown in Figure 2(a).

[038] The controller 250 of the unmanned vehicle 230 may keep on sending the collected data to the remote device 210 via the network 220 in real time. The remote device 210 may generate a comprehensive report on the water quality using the data received from the unmanned vehicle 230. In as aspect, the remote device 210 may generate a choropleth map based on the data received from the unmanned vehicle 230. In one non-limiting embodiment, the collected data may be used to predict the trend of water quality of the water body 120 based on historical water quality data. Also, the data may be used to understand which regions of the water body 120 have worst water quality (e.g., due to pollution) and which regions are safer. This, may help in taking corrective actions in time thereby protecting the aquatic life and resolving the water quality issues before public is affected.

[039] In one non-limiting embodiment, the unmanned vehicle 230 may further comprise a drone which can fly along a pre-set route (e.g., in hilly areas) for collecting the data related to the water quality. In the present disclosure, it has been shown that the robotic arm extends and retracts in a linear manner. However, the present disclosure is not limited thereto and in general the robotic arm 242 may extend /retract in such a manner that all of the plurality of links 244 may extend/retract with same distance and same angle forming a zig-zag pattern.

[040] Referring now to Figure 4, a flowchart is described illustrating an exemplary method 400 for monitoring liquid quality using an unmanned vehicle 230 which is configured to float over a liquid surface, according to an embodiment of the present disclosure. The method 400 is merely provided for exemplary purposes, and embodiments are intended to include or otherwise cover any liquid quality monitoring methods.

[041] The method 400 may include, at block 402, providing a robotic assembly 240 comprising an arm 242 having a plurality of links 244 movable with respect to each other to extend and retract the arm 242; and one or more sensors 248 mounted on the arm 242. The one or more sensors 248 may be configured to collect data related to the liquid quality.

[042] At block 404, the method 400 may include operating the arm 242 of the robotic assembly 240 from a retracted position to an extended position and vice-versa for collecting the data related to the liquid quality. For example, the controller 250 may be configured to operate the arm 242 of the robotic assembly 240 from the retracted position to the extended position and vice-versa for collecting the data related to the liquid quality.

[043] In one non-limiting embodiment of the present disclosure, the method may further include collecting the data related to the liquid quality at one or more depth levels in real-time while operating the arm 242 of the robotic assembly 240, from the retracted position to the extended position and vice-versa, into the liquid. For example, the controller 250 may be configured to collecting the data related to the liquid quality at one or more depth levels in real-time while operating the arm 242 of the robotic assembly 240 from the retracted position to the extended position and vice-versa.

[044] In one non-limiting embodiment of the present disclosure, the method may further include measuring a liquid depth using at least one depth sensor 246 and extending the arm 242 of the robotic assembly 240 into the liquid up to the liquid depth. Particularly, extending the arm 242 of the robotic assembly 240 into the liquid may comprise extending the arm 242 of the robotic assembly 240 into the liquid such that there is a minimum distance between the arm 242 and the bottom water surface 120-2 of the liquid source 120.

[045] In one non-limiting embodiment of the present disclosure, the method may further include communicating with a navigation system for navigating the unmanned vehicle 230 within a pre-defined area to measure the liquid quality at different locations.

[046] In one non-limiting embodiment of the present disclosure, the robotic assembly 240 may be placed on a surface of the unmanned vehicle 230 or the unmanned vehicle 230 may comprise an opening at a bottom side thereof and the robotic assembly 240 may be disposed within a space defined within the opening.

[047] The above method 400 may be described in the general context of computer executable instructions. Generally, computer executable instructions can include routines, programs, objects, components, data structures, procedures, modules, and functions, which perform specific functions or implement specific abstract data types.
[048] It may be noted here that the subject matter of some or all embodiments described with reference to Figures 1-3 may be relevant for the methods and the same is not repeated for the sake of brevity.

[049] The above subject matter discloses an unmanned vehicle which is capable of remotely monitoring the liquid quality in all types of environments and all types of liquid sources. The proposed techniques assist in tracking the water quality in real time. Further, the unmanned vehicle can monitor the liquid quality not only at water surface but at different depth levels as well.

[050] It is intended that the disclosure and examples be considered as exemplary only, with a true scope and spirit of disclosed embodiments being indicated by the following claims.