Airborne system and method for characterising and collecting water

Abstract

The present invention relates to an airborne method and system for characterising and collecting water from an aquatic medium, comprising an aerial drone (1), the aerial drone (1) comprising an optical sensor (2) and a means for receiving / transmitting data comprising a geolocation means, the system comprising an instrumentation device comprising at least one means (4b) for collecting water from an aquatic medium, and a first winch (3) which is mounted on the aerial drone (1) and is able to position the instrumentation device at a predetermined depth in the aquatic medium. Moreover, the aerial drone (1) is able to be held in the aerial position during the collection and / or characterisation of the water, and the instrumentation device comprises a data-acquisition means (4a) for measuring at least the pressure, the temperature and / or the conductivity of the water within the aquatic medium and preferably allowing the transmission of the data in real time to the means for receiving / transmitting data.

Description

[0001] SYSTEM AND METHOD FOR CHARACTERIZATION AND SAMPLING OF AIRBORNE WATER

[0002] Technical field

[0003] The present invention relates to the field of water characterization and sampling, in particular to identify / characterize sources of fresh water and / or drinking water.

[0004] Prior art

[0005] In hydrogeology, the characterization and sampling of water from different points (springs, rivers, reservoirs, wells, lakes, etc.) are essential. Characterization can be done in situ or through water sampling, which is then analyzed in the laboratory.

[0006] This water characterization then requires a significant investment in human resources as well as numerous trips to sites with varying degrees of access. Furthermore, certain areas are difficult to access, for example, in the open sea or in steep regions such as in the mountains.

[0007] If the analyses for water characterization are carried out on a large scale, it is then possible to identify different hydrosystems whose interactions will also be established by these analyses.

[0008] In order to carry out water sampling, some solutions consider the use of floating or underwater drones.

[0009] Underwater drones have the disadvantage of requiring cables for data transmission, thus complicating the system.

[0010] Floating drones are difficult to use in areas where the water is particularly rough, especially on the surface, such as coastal areas, because the drone could be capsized and sunk, and because water sampling can be difficult in rough water. Therefore, these floating drones are currently used in relatively calm ponds, lakes, or rivers.

[0011] Thus, the aim of the invention is to design a robust system and method, which allow the characterization and sampling of water in areas of difficult access (in particular at sea and more particularly near the coasts), in order to detect underwater or coastal sources. The system and method must also be designed to allow the sampling and characterization of water whatever the water conditions (sea conditions for example: swell, current etc. ...), while limiting human resources and reducing intervention time.

[0012] In addition, the system and method of the invention must allow the sampling and characterization of water at different water depths. The system and method can in particular be used to identify at least one source of fresh water (or low salinity, i.e. less saline than sea water) underwater or coastal in order to locate these sources and identify the ideal installation area for a system for capturing this fresh water.

[0013] Summary of the invention

[0014] The invention relates to an airborne system for characterizing and sampling water from an aquatic environment comprising an aerial drone, the aerial drone comprising an optical sensor and a data reception / transmission means comprising a geolocation means, the system comprising an instrumentation device comprising at least one means for sampling water from an aquatic environment, a first winch mounted on the aerial drone and capable of positioning the instrumentation device at a predetermined depth in the aquatic environment. In addition, the aerial drone is capable of being maintained in an aerial position during the sampling and / or characterization of the water and in that the instrumentation device comprises a data acquisition means for measuring at least the pressure, the temperature and / or the conductivity of the water within the aquatic environment and preferably allowing the transmission of the data in real time by the data reception / transmission means.

[0015] Preferably, the optical sensor comprises an optical sensor in the visible spectrum and / or an optical sensor in the infrared spectrum.

[0016] According to one variant, the data acquisition means comprises a means for measuring the pH, the dissolved oxygen level in the water and / or the turbidity.

[0017] Advantageously, the system includes a second winch mounted on the aerial drone and capable of emptying the sampling means.

[0018] Advantageously, the sampling means comprises several sampling tanks.

[0019] Preferably, the system comprises a means for processing images from the optical sensor.

[0020] The invention also relates to a method for characterizing and sampling water from a system as described above, for which at least the following steps are carried out: a) the aerial drone is moved by air above an aquatic environment, b) the optical sensor is used to determine an area of ​​interest in which the water is to be characterized, c) the aerial drone is stabilized in hovering flight at a predetermined point above the determined area of ​​interest, and a location measurement is acquired from the geolocation means, then the first winch is used to lower said instrumentation device to a first predetermined depth in the aquatic environment, d) at least the pressure, temperature and conductivity measurements are acquired by the data acquisition means, to carry out a first characterization of the water, preferably said measurements are acquired in real time,e) a water sample is taken from said aquatic environment at said first predetermined depth by the sampling means, and additional analyses are carried out on the water sampled to carry out a second characterization of the water.,

[0021] Preferably, in step e), a water sample is taken from said aquatic environment at said first depth by the sampling means if the acquired pressure, temperature and conductivity data meet predetermined criteria, and if not, the aerial drone is moved to another point in the determined area of ​​interest and the process is resumed from step c).

[0022] Advantageously, in step e), before carrying out each water sample, a rinsing phase of the sampling means is carried out, this rinsing phase comprising at least three repetitions of the sequence in which the sampling means is filled with water from the aquatic environment and the water is emptied from the sampling means, preferably using a second winch.

[0023] According to one aspect of the invention, the additional analyses of the water comprise an analysis of the isotopes of the water and / or chemical measurements preferably comprising measurements of organic carbon.

[0024] According to one variant, different measurements are acquired using the data acquisition means at different first predetermined depths and / or at different predetermined points above the determined area of ​​interest.

[0025] Preferably, at the same predetermined point in the area of ​​interest and at several water depths, the measurements are acquired by the data acquisition means and preferably, water is sampled by the sampling means, without having to raise the instrumentation device by the first winch and preferably in real time.

[0026] Advantageously, the aerial drone, the optical sensor, the geolocation means, the first winch and the possible second winch are controlled by several control means.

[0027] Preferably, digital processing of the images from the optical sensor is carried out to determine the area of ​​interest.

[0028] List of figures Other characteristics and advantages of the method and / or system according to the invention will appear on reading the following description of non-limiting examples of embodiments, with reference to the figures appended and described below.

[0029] Figure 1 represents a first embodiment of the water characterization and sampling system according to the invention.

[0030] Figure 2 represents a second embodiment of the water characterization and sampling system according to the invention.

[0031] Figure 3 represents a first variant of the method of characterizing and sampling water according to the invention.

[0032] Figure 4 represents a second variant of the method of characterizing and sampling water according to the invention.

[0033] Description of the embodiments

[0034] The invention relates to an airborne system for characterizing and sampling water from an aquatic environment (which may also be called an aqueous environment). The aquatic environment may be a lake, a pond, a river, a sea or an ocean and, more particularly, it may be an underwater or coastal source of water (more particularly fresh water) which flows into a sea or an ocean.

[0035] By "aqueous medium" or "aquatic medium" is meant a medium composed essentially of water, that is to say, mostly water.

[0036] The water surface can then be very strongly disturbed by waves, swell, current or the presence of the nearby coast, so that the detection of the nearby fresh water source is made difficult, as is the characterization and sampling of this water.

[0037] The system comprises an aerial drone equipped with various payloads, also called UAS (for "Unmanned Aerial System" in English, which means unmanned aerial system). For the purposes of the invention, an aerial drone is a drone capable of being moved by air, with a pilot not on board the drone (on the ground for example) or piloted automatically by a computer system (for example a computer, a server or a calculator). Preferably, the drone is configured for automatic or manual radio-controlled piloting. As a result, the UAS can be brought into areas that are difficult to access, such as near a coastal area at sea or in a particularly steep area in the mountains. Thus, moving the system is simple and rapid and limits the risk and intervention time for operators.This aerial drone may not include a water landing system: it is therefore simpler, less expensive, lighter and less complex than a drone with a water landing system.

[0038] The aerial drone includes an optical sensor in the visible light spectrum and / or an optical sensor in the infrared spectrum. These different sensors are an aid in determining potential study areas or "areas of interest", based on the color of the water, which is different between freshwater and seawater, using the optical sensor in the visible light spectrum, and / or based on the water temperature (using the optical sensor in the infrared spectrum). By identifying the area of ​​interest more precisely using these optical sensors, the water in this area can be characterized and thus the number of samples and characterizations can be limited. This allows results to be obtained more quickly and efficiently. These optical sensors make it possible to limit the extent of the area in which in situ water characterizations and water samples will be taken.

[0039] The aerial drone is also equipped with data reception / transmission means (e.g. receiver / transmitter). Thus, the UAS can receive information (e.g. to control a winch and / or measuring probes), this information can for example come from a user. The aerial drone can also receive information from measurement data, for example from water measurement sensors. This data is then recorded (stored) in the data reception / transmission means (e.g. in a computer or electronic card). The aerial drone can also transmit data: for example, it can transmit the measurement data either in real time to a user, or after their storage and retrieval by the user via the computer or electronic card for example.

[0040] The UAS further comprises a geolocation means, which may advantageously be included in the data reception / transmission means (for example, the system known as GPS for "Global Positioning System" or GNSS for "Global Navigation Satellite System" meaning satellite positioning system in French, the GNSS being able to capture GPS satellites or other constellations such as Galileo, the European system, Glonass, the Russian system, or even the Chinese system). Thus, the precise position of the drone can be known at the time of the measurements and / or water sampling. The geolocation data from the geolocation means can be received in the data reception / transmission means (the computer or electronic map for example) and / or be transmitted to a user (via the computer or electronic map for example or in real time).

[0041] In addition, the system comprises an instrumentation device comprising at least one means for sampling water from the aquatic environment, a first winch mounted on the aerial drone and capable of positioning the instrumentation device at a predetermined depth in the aquatic environment. Thus, thanks to the first winch and the sampling means, it is possible to sample water from the aquatic environment at different water depths for the same geolocation position. Thus, by repeating these samples for several geolocation positions of the area of ​​interest, it is possible to establish a 3D map of the characteristics of the water in the identified area of ​​interest.

[0042] Preferably, the drone can also be programmed to follow a sampling plan consisting of several geolocation positions in the area of ​​interest and one or more water depths for each geolocation position.

[0043] The sampling means may comprise at least one open container, such as a reservoir or a bottle. Alternatively, it may comprise at least one instrument such as a syringe equipped with a piston. Moving the piston located inside the syringe in a direction allowing the internal volume of the syringe to be increased allows water to be drawn from the aquatic environment, moving the piston in the opposite direction allows the syringe to be emptied.

[0044] The sampling means can advantageously be configured to be able to sink even when empty, so as to facilitate its immersion to the desired depth.

[0045] Furthermore, the aerial drone is capable of being maintained in an aerial position during the sampling and / or characterization of the water (it therefore does not need to land on water to carry out the measurements and / or the water sampling and it may therefore not include a landing system) and the instrumentation device comprises a data acquisition means (probes or measurement sensors, for example autonomous data acquisition probes used for the measurement and recording of parameters such as level, temperature and electrical conductivity) to measure at least the pressure, temperature and / or conductivity of the water within the aquatic environment.

[0046] Autonomous data acquisition probes can include probes known as Diver probes, for measuring level, temperature and conductivity.

[0047] For example, the data acquisition means can be connected to the control means by cable or be radio controlled.

[0048] The data acquisition means may also include multi-parameter probes to measure both level, temperature and electrical conductivity and other parameters such as pH, dissolved oxygen level and / or turbidity.

[0049] According to one variant, the acquisition means may comprise at least one piezometric probe, in particular at least one autonomous piezometric probe with data acquisition.

[0050] Indeed, by maintaining the aerial position during water sampling or its in situ characterization, the drone can be moved away from the water surface and thus it no longer undergoes or very little (only through the cable of the first winch and a possible second winch) the impacts of disturbances of the water surface, in particular linked to swell, current or the presence of the nearby coast. As a result, the system can be used in areas where landing is impossible and / or where the water is highly disturbed (for example, in a river) or too small. In addition, the data acquisition means allows in situ measurements of pressure, temperature and / or conductivity of the water. It can thus include a sensor for measuring the pressure, temperature and / or conductivity of the water within the aquatic environment itself.Thus, the use of these in situ data makes it possible to plan or not to take a water sample at this given location (from geolocation) and at the given depth (from the first winch). Indeed, if the measured data of pressure, temperature and / or conductivity of the water are not satisfactory, a water sample is then not necessary. In other words, the data measured by the data acquisition means make it possible to establish an initial selection of the water to take or not to take a water sample. The number of samples to be taken can then be reduced. The water sample makes it possible to complete the characterization of the water that was done by the data acquisition means with other complementary measurements of the water, these complementary measurements not being possible in situ and allowing access to additional characteristics of water characterization.The combination of a sampling method with a data acquisition method thus makes it possible to make the characterization of the water faster and more efficient and to target the area of ​​interest more quickly, while remaining precise.

[0051] Measuring pressure, temperature and / or conductivity allows us to assess the density and / or salinity of the water. These measurements allow us to know whether or not the water at the identified geolocation point and at the identified depth corresponds to fresh water. In addition, thanks to 3D mapping that can be carried out on the area of ​​interest and for different water depths, we can characterize the most interesting location for collecting drinking water, this location being able to depend on the outlet of one or more sources, the current, the swell and the presence of the nearby coast for example.

[0052] Preferably, the data acquisition means may enable transmission of the data in real time to the data receiving / transmitting means.

[0053] Real-time transmission of acquired measurement data accelerates characterization and reduces intervention time.

[0054] Advantageously, the optical sensor may comprise an optical sensor in the visible light spectrum and / or an optical sensor in the infrared spectrum. The optical sensors may be cameras. A thermal camera, also called an infrared camera, detects and measures light waves whose spectrum is in the infrared range. It makes it possible to determine the temperature of a body by the infrared radiation that it emits. The viewing camera is an optical or digital camera that makes it possible to view the environment substantially like the human eye. It detects objects in the visible range between red (excluding infrared) and violet (excluding ultraviolet).

[0055] As the optical sensor is on the aerial drone, it is located above the water surface and can detect variations in color and / or temperature to determine an area of ​​interest in which it will be interesting to carry out measurements and / or take water samples. By analyzing both the measurement of the optical sensor in the visible light spectrum and that of the optical sensor in the infrared spectrum, the data can be cross-referenced and a more precise area of ​​interest defined. This allows for faster water characterization and better targeting of the area where it would be interesting to capture fresh water, for example.

[0056] Preferably, the data acquisition means may also comprise a means for measuring the pH, the dissolved oxygen level in the water and / or the turbidity. The measured temperature and pH may in particular provide information on the origin of the water: these data may provide information on the original aquifer, the land drained by this aquifer, but also the very origin of the water, whether for example meteoric (rain) water infiltrated into the aquifer, sea water reinjected into the aquifer, or underground and deep formation / hydrothermal water.

[0057] Measuring dissolved oxygen in water is a measure of water quality.

[0058] Dissolved oxygen refers to the level of free, non-compound oxygen present in water or other liquids. It is an important biological and chemical parameter in assessing water quality due to its influence on living organisms in a body of water. A dissolved oxygen level that is too high or too low can be detrimental to aquatic life and water quality. For example, a level between 0 and 2 mg of dissolved oxygen per liter (1 liter corresponding to 0.001 m3) of water is insufficient for the survival of most organisms. A level between 2 and 4 mg of dissolved oxygen per liter of water is sufficient for only some species of fish and insects to survive.Between 4 and 7 mg of dissolved oxygen per liter of water is acceptable oxygen level for warm water fish species but remains low for cold water fish species while a level between 7 and 11 mg of dissolved oxygen per liter of water is ideal for most cold water fish.

[0059] When dissolved oxygen levels are too high, they can also be dangerous for fish, for example. Turbidity measurement helps identify water quality and any suspended particles it contains. All of these measurements can be integrated into a single sensor, such as a standalone data acquisition probe.

[0060] Turbidity is the measurement of the content of suspended particles and colloidal particles in water that absorb, scatter, or reflect light and thus cloud the water. It is therefore, like dissolved oxygen, an indicator of water quality.

[0061] For aquatic measurements, turbidity is measured in nephelometric turbidity units (NTU) using a turbidimeter. For example, at 5 NTU, the water is visibly cloudy, while at 25 NTU, it is blackish.

[0062] According to one configuration of the invention, the system may comprise a second winch mounted on the aerial drone and capable of emptying the sampling means. Indeed, in order to improve the quality of the water samples, it is advantageous to carry out a rinsing operation before each sample. This rinsing operation may in particular comprise at least one filling of the sampling means with water from the aquatic environment, followed by an emptying of the sampling means, preferably at least three fillings, each filling being followed by an emptying of the sampling means.

[0063] When the sampling means is a tank, one end of the tank can be attached to the first winch and thus allows filling, the second end of the tank can then be attached to the second winch. By operating the second winch, the tank can then be tilted, and therefore emptied.

[0064] Advantageously, the sampling means may comprise several sampling tanks and / or several instruments such as syringes. Thus, at a given point (at a given location), water can, for example, be sampled at different depths. At each depth, a separate sampling tank (or a separate syringe) is then filled. Water can also be sampled from a sampling tank for different given points (at different locations) for the same depth or for different water depths. Thus, the system is very flexible in terms of uses, and it is faster to take samples. When the sea is very rough, this also reduces intervention time and limits the risk of damage to the equipment.

[0065] Preferably, the system may comprise a means for processing images from the optical sensor, such as image processing software. On the one hand, this digital processing may be faster than human processing, for example by establishing pre-established criteria indicated in the software and on the other hand, this image processing may be carried out in real time, which further shortens the intervention and characterization time of the water and facilitates decision-making regarding the definition of the area of ​​interest.

[0066] Once the water sample has been established, the water sample can be analyzed in the laboratory. For example, a study of water isotopes and organic carbon measurements provide information on the residence time of the water in the geological reservoir (an aquifer for example).

[0067] The residence time of water in the aquifer provides information on the transfer duration and therefore indirectly on the permeability of the terrain. In the case of karst aquifers, the residence time can be extremely short (from a few days to a few weeks), which is due to the presence of caverns and underground voids. These voids can act as temporary storage (buffers) that will delay the transfer of water between recharge and outlet.

[0068] Residence time also provides an indication of the water renewal rate in the aquifer. In the case of a exploited aquifer, this is therefore a key piece of information for estimating the sustainability of the resource and improving its sustainable management by establishing hydrodynamic models. It is also an important parameter for estimating the aquifer's sensitivity to pollution: an aquifer with a short renewal time will be very sensitive to the potential arrival of pollutants. It will nevertheless be able to return to a good chemical state if the source of pollution is stopped. An aquifer with a long residence time, on the other hand, if contaminated, will not be able to quickly return to a good chemical state.

[0069] The invention also relates to a method for characterizing and sampling water from a system as described above, for which at least the following steps are carried out: a) the aerial drone is moved by air above an aquatic environment. As a result, the system and the method can be used in areas that are difficult to access and / or in areas where the water conditions (particularly on the surface) are highly disturbed. The aerial drone does not require a water landing system. b) the (at least one) optical sensors are used to determine an area of ​​interest in which the water is to be characterized. By using these optical sensors located under the aerial drone, the surface of the water can be visualized at an altitude of the drone above the surface.This aerial visualization makes it possible to visualize a difference in water color (optical sensor in the visible light spectrum) or a difference in temperature (optical sensor in the infrared spectrum). This difference in color and / or temperature can then be used to identify an area of ​​interest where the water will be characterized. By using both the optical sensor in the visible light spectrum and the optical sensor in the infrared spectrum, the area of ​​interest can be narrowed, i.e., the extent of this area can be limited and therefore its accuracy improved. c) the aerial drone is stabilized in hovering flight on a predetermined point above the determined area of ​​interest. By remaining in hovering flight, the aerial drone is not (or very little via the first winch) subject to disturbances in the water, and in particular to disturbances in the water surface. The aerial drone is thus kept safely away from the water surface.Furthermore, the optical sensor can always be used simultaneously. Once the aerial drone is in a hovering flight, a location measurement is acquired from the geolocation means so as to be able to accurately determine the location, then the first winch is used to lower said instrumentation device to a first predetermined depth in the aquatic environment. Thus, it is only the winch cable that is subject to the disturbance of the water surface. Consequently, it is little disturbed and the measurements remain accurate (the measurements and samples taken are made at the determined location). d) at least the pressure, temperature and / or conductivity measurements, and possibly the oxygen level in the water, turbidity and / or pH, are acquired by the data acquisition means, to carry out a first characterization of the water.By these measurements of pressure, temperature and / or conductivity, and possibly oxygen levels in the water, turbidity and / or pH, we can determine the first characteristics of the water such as the density and / or salinity of the water and therefore identify for example whether or not it is drinking water (water is considered drinkable if its salinity is less than 0.2g / L according to WHO standards). Preferably, the measurements can be acquired in real time. This allows for faster analysis and avoids unnecessary water sampling if the salinity is too high for example. e) a water sample is taken from the aquatic environment at the first depth by the sampling means (a tank or a sampling syringe for example) and additional analyses are carried out on the sampled water to carry out a second characterization of the water.The water sampled allows for additional laboratory analyses, these additional analyses not being possible directly in situ and making it possible to define second characteristics of the water or to refine the first characteristics of the water to make them more precise.

[0070] Preferably, in step e), a water sample can be taken from the aquatic environment at the first depth by the sampling means if the acquired data of pressure, temperature and conductivity, and possibly pH, dissolved oxygen level in the water and / or turbidity, meet predetermined criteria, for example if the salinity of the water, determined from the measurements, is less than 10% of the salinity of the surrounding environment. Otherwise, the aerial drone can be moved to another point in the determined area of ​​interest and the process is resumed from step c). If the predetermined criteria are not met (if the salinity is too high), the point is deemed not to be of interest, sampling is then not necessary and the process consists of finding another point above the determined area of ​​interest.Advantageously, in step e), before carrying out each water sample, a rinsing phase of the sampling means can be carried out, this rinsing phase comprising at least three repetitions of the sequence in which the sampling means is filled with water from the aquatic environment and the water is emptied from the sampling means, preferably using a second winch. These rinsing phases make it possible to improve the precision of the characterization of the water.

[0071] According to one embodiment of the invention, the additional analyses of the water may comprise an analysis of the isotopes of the water and / or chemical measurements preferably comprising measurements of organic carbon. These analyses provide information on the residence time of the water in its geological reservoir.

[0072] According to one implementation of the invention, different measurements can be acquired using the data acquisition means at different first predetermined depths and / or at different predetermined points above the determined area of ​​interest. Thus, a map of the characterization of the water in the area of ​​interest can be established and thus the most interesting place to capture fresh water can be identified, for example.

[0073] Preferably, at the same predetermined point in the area of ​​interest and at several water depths, measurements can be acquired by the data acquisition means and preferably, water can be sampled by the sampling means, without having to raise the instrumentation device by the first winch. Thus, the characterization of the water is more precise and the mapping that can be established can also be more precise. In addition, by sampling the water without having to raise the instrumentation device, the intervention time is reduced. Preferably, these samples and acquisitions can be carried out in real time to further accelerate the characterization of the water and possibly gain even more precision.

[0074] According to an advantageous variant of the invention, the aerial drone, the optical sensor, the geolocation means, the first winch and the possible second winch can be controlled by several control means. For example, the aerial drone, the optical sensor, the geolocation means can be controlled by a first control means (control by a first user for example) and the control of the first winch, and of the possible second winch, can be controlled by a second control means (control by a second user distinct from the first user for example). Thus, the first user can concentrate exclusively on piloting the aerial drone and the second user takes care of handling the instrumentation device to carry out the necessary measurements and / or samples (and the possible rinsing of the sampling means by means of the second winch).This way, operations are secure and the risk of system hardware loss is reduced, as each user has a unique function.

[0075] Alternatively, the first user and the second user (their controls / piloting means) can be replaced by a computer.

[0076] Preferably, digital processing of the images from the optical sensor may be performed to determine the area of ​​interest. This digital processing may make it possible to narrow the area of ​​interest by limiting its extent or to obtain the area of ​​interest more quickly or more efficiently. For example, the digital processing may include processing of data from an optical sensor in the visible light spectrum and processing of data from the optical sensor in the infrared spectrum.

[0077] Figure 1 illustrates, in a schematic and non-limiting manner, a first embodiment of the airborne water characterization and sampling system.

[0078] This system comprises an aerial drone 1 which does not comprise a water landing system. An optical sensor 2, such as a camera, is attached to the aerial drone 1. The optical sensor 2 is positioned so as to allow the recording of visual and / or thermal images below the drone (below when the drone is in flight or hovering) so as to visualize the surface of the water located below the drone.

[0079] The system also includes a winch 3 on which a cable can be wound or unwound. The winch 3 is mounted on the aerial drone 1. One end of the cable is attached to the winch 3. At the other end of the cable, an instrumentation device is attached.

[0080] The instrumentation device comprises a sampling tank 4b and a self-contained data acquisition probe 4a for measuring pressure, temperature, conductivity, pH, dissolved oxygen level in the water and turbidity of the water.

[0081] When the winch is activated in a first position, the cable is unwound and the instrumentation device is then positioned to a certain depth below the water surface. Conversely, when the winch is activated in a second position, the cable is wound up, which allows the instrumentation device to be recovered. Thus, the water sampled in the sampling tank 4b can be recovered. In addition, if the measurements from the autonomous data acquisition probe 4a were not transmitted in real time and were stored in an electronic card, a user can then retrieve this card and the associated data recorded thereon.

[0082] As illustrated, a first user 6a can pilot the drone, namely its trajectory, by means of the optical sensor 2 and a geolocation means included in the aerial drone 1 and another user 6b can pilot the first winch 3 so as to lower or raise the instrumentation device.

[0083] Alternatively, both drivers could be replaced by a computer (as in Figure 2 described later). The process (or system) is then implemented by computer and is automatic.

[0084] Figure 2 illustrates, in a schematic and non-limiting manner, a second embodiment of the airborne water characterization and sampling system.

[0085] References identical to those in Figure 1 correspond to the same elements and will not be detailed again.

[0086] This system is distinguished from figure 1 by a second winch 7 also mounted on the aerial drone 1.

[0087] One end of a second cable is attached to this second winch 7. The other end of the second cable is attached to one end of the sampling tank 4b, the other end of the tank being connected to the first cable attached to the first winch 3.

[0088] To lower the instrumentation device to a predetermined depth, the first and second cables of the first winch 3 and the second winch 7 are unwound simultaneously and the instrumentation device is then positioned to a certain depth below the water surface. Water sampling can then take place. To empty the sampling tank 4b (for rinsing it for example), the winch is activated to wind up the second cable.

[0089] In addition, a computer 6c can then retrieve the data from the autonomous data acquisition probe 4a, in real time or retrieve the data recorded on an electronic card if the measurements from the autonomous data acquisition probe 4a were not transmitted in real time but stored in the electronic card.

[0090] As illustrated, the computer 6c (alternatively a first user as in Figure 1) can pilot the drone, namely its trajectory, by means of the optical sensor 2 and a geolocation means included in the aerial drone 1 and the computer 6c (alternatively another user 6b) can pilot the first winch 3 so as to lower or raise the instrumentation device. When the method and the system are implemented by computer, they are automatic. As discussed, the computer can be replaced by two users as in Figure 1, one to pilot in particular the drone and the other to pilot the first winch.

[0091] Figure 3 illustrates, in a schematic and non-limiting manner, a first variant of the method for characterizing and sampling water according to the invention.

[0092] In this method, at least the following steps are carried out: a) the aerial drone is moved Dep by air above an aquatic environment, b) the optical sensor is used Cam to determine a zone of interest ZI in which the water is to be characterized by determining variations in color and / or temperature on the surface of the water from the optical sensor, c) the aerial drone is stabilized Stat in hovering flight on a predetermined point Pt above the determined zone of interest and a location measurement of the determined point Pt is acquired from the geolocation means and then the first winch is used to lower the instrumentation device to a first predetermined depth Pf in the aquatic environment, d) at least the pressure, temperature and conductivity measurements, and possibly pH, dissolved oxygen level in the water and / or turbidity are acquired by the data acquisition means,to carry out a first characterization of the water, preferably the measurements are acquired in real time, e) a water sample is taken Prel in the aquatic environment at the first predetermined depth Pf by the sampling means and additional analyses are carried out on the water sampled to carry out a second characterization of the water.,

[0093] Once the water sample has been taken at the first predetermined depth Pf, it is possible to modify the water depth to resume the process from step c).

[0094] It is also possible to modify the determined point Pt to carry out the characterization of the water and / or its sampling at another determined point Pt of the zone of interest ZI.

[0095] From these in situ characterization measurement data and possible second characterizations in the laboratory from water samples, it is possible to establish a map of the water characteristics in the area of ​​interest ZI as a function of the water depth Pf and the determined points Pt.

[0096] In the figure, the dashed arrow shows an optional repetition of steps c) to e).

[0097] Figure 4 illustrates, in a schematic and non-limiting manner, a second variant of the method for characterizing and sampling water according to the invention. The references identical to those in Figure 3 correspond to the same elements and will not be detailed again.

[0098] This figure differs from figure 3 by the addition of a rinsing step Rin of the sampling means before the sampling step Prel. Therefore, after having carried out step d) of data acquisition Acq by the data acquisition means, the sampling means can be rinsed so as to avoid any pollution of the sampling sample.

[0099] Once the water sample has been taken at the first predetermined depth Pf, it is possible to modify the water depth to resume the process from step c).

[0100] It is also possible to modify the determined point Pt to carry out the characterization of the water and / or its sampling at another determined point Pt of the zone of interest ZI.

[0101] From these in situ characterization measurement data and possible second characterizations in the laboratory from water samples, it is possible to establish a map of the water characteristics in the area of ​​interest ZI as a function of the water depth Pf and the determined points Pt.

[0102] In the figure, the dashed arrow shows an optional repetition of steps c) to e).

[0103] It is important to specify that, in Figures 3 and 4, the sampling step (and the possible preliminary rinsing phase) may not be carried out if the data from acquisition step d) are not satisfactory (if the salinity of the water is too high, for example greater than 5g / L). In this case, the drone is moved to a new determined point in the area of ​​interest and the process is resumed once the aerial drone is hovering above this new determined point.

[0104] The system and method are not limited to the examples described but rather embrace variants without departing from the scope of the invention.

Claims

Claims 1. Airborne system for characterizing and sampling water from an aquatic environment comprising an aerial drone (1), the aerial drone (1) comprising an optical sensor (2) and a data reception / transmission means comprising a geolocation means, the system comprising an instrumentation device comprising at least one means (4b) for sampling water from an aquatic environment, a first winch (3) mounted on the aerial drone (1) and capable of positioning the instrumentation device at a predetermined depth in the aquatic environment, characterized in that the aerial drone (1) is capable of being maintained in an aerial position during the sampling and / or characterization of the water and in that the instrumentation device comprises a data acquisition means (4a) for measuring at least the pressure,the temperature and / or conductivity of the water within the aquatic environment and preferably allowing the transmission of data in real time by means of data reception / transmission., 2. Airborne system for characterizing and sampling water from an aquatic environment according to claim 1, for which the optical sensor (2) comprises an optical sensor in the visible spectrum and / or an optical sensor in the infrared spectrum.

3. Airborne system for characterizing and sampling water from an aquatic environment according to one of the preceding claims, for which the data acquisition means (4a) comprises a means for measuring the pH, the level of oxygen dissolved in the water and / or the turbidity.

4. Airborne system for characterizing and sampling water from an aquatic environment according to one of the preceding claims, for which the system comprises a second winch (4) mounted on the aerial drone (1) and capable of emptying the sampling means (4b).

5. Airborne system for characterizing and sampling water from an aquatic environment according to one of the preceding claims, for which the sampling means (4b) comprises several sampling tanks.

6. Airborne system for characterizing and sampling water from an aquatic environment according to one of the preceding claims, for which the system comprises means for processing images from the optical sensor (2).

7. Method for characterizing and sampling water from a system according to one of the preceding claims, for which at least the following steps are carried out: a) the aerial drone (1) is moved (Dep) by air above an aquatic environment, b) the optical sensor (2) is used (Cam) to determine a zone of interest (ZI) in which the water is to be characterized, c) the aerial drone (1) is stabilized (Stab) in hovering flight at a predetermined point (Pt) above the determined zone of interest (ZI), and a location measurement is acquired from the geolocation means and then the first winch (3) is used to lower said instrumentation device to a first predetermined depth in the aquatic environment, d) at least the pressure, temperature and conductivity measurements are acquired by the data acquisition means (4a), to carry out a first characterization of the water, preferably said measurements are acquired in real time, e) a water sample is taken (Prel) in said aquatic environment at said first predetermined depth (Pf) by the sampling means (4b),and additional analyses are carried out on the water sampled to carry out a second characterization of the water.

8. Method for characterizing and sampling water according to claim 7, for which, in step e), a water sample is taken (Prel) in said aquatic environment at said first depth by the sampling means if the acquired pressure, temperature and conductivity data meet predetermined criteria, and otherwise, the aerial drone (1) is moved to another point in the determined area of ​​interest and the procedure is resumed from step c).

9. Method for characterizing and sampling water according to one of claims 7 or 8, in which, in step e), before carrying out each water sampling, a rinsing phase (Rin) of the sampling means is carried out, this rinsing phase comprising at least three repetitions of the sequence in which the sampling means (4b) is filled with water from the aquatic environment and the water is emptied from the sampling means (4b), preferably using a second winch (7).

10. Method for characterizing and sampling water according to one of claims 7 to 9, for which the additional analyses of the water comprise an analysis of the isotopes of the water and / or chemical measurements preferably comprising measurements of organic carbon.

11. Method for characterizing and sampling water according to one of claims 7 to 10, for which different measurements are acquired using the data acquisition means (4a) at different first predetermined depths (Pf) and / or at different predetermined points (Pt) above the determined zone of interest (ZI).

12. Method for characterizing and sampling water according to claim 11, for which, at the same predetermined point (Pt) of the area of ​​interest and at several water depths (Pf), the measurements are acquired by the acquisition means of data (4a) and preferably, water is sampled by the sampling means (4b), without having to raise the instrumentation device by the first winch (3) and preferably in real time.

13. Method for characterizing and sampling water according to one of claims 7 to 12, for which the aerial drone (1), the optical sensor (2), the geolocation means, the first winch and the possible second winch are controlled by several control means.

14. Method for characterizing and sampling water according to one of claims 7 to 13, for which digital processing of the images from the optical sensor (2) is carried out to determine the area of ​​interest.

Images