A method for measuring a body of water and a measuring system for this purpose.

Abstract

A method for measuring a body of water includes positioning a drone (23) having a rod (53) suspended from the drone (23) at a location above the body of water (1) and lowering the drone (23) such that a lower end (55) of the rod (53) passes through a surface of the water (57) of the body of water (1). The drone (23) is then lowered further so that the lower end (55) of the rod (53) penetrates a layer of sediment (7) deposited on the bottom (9) of the body of water (1). The drone (23) is then lowered further, and the rod (53) is driven into the sediment layer (7) until an interruption criterion is reached. A quantity representing the height (h) of the drone at the location (51) is then measured when the interruption criterion is reached. Finally, a thickness (D1) of the sediment layer (7) is calculated at location (51). (Figure 1)

Description

Title of the invention: Method for measuring a body of water and measuring system for this purpose

[0001] The present invention relates to a method for measuring a body of water and a measuring system for this purpose.

[0002] A body of stagnant or flowing water is an accumulation of water in a depression in the ground. The ground is generally composed of earth, stones, concrete, gravel, or similar materials. The height of the water level in the body of water is determined by the inflow of water into the body of water, the outflow of water from the body of water, and evaporation.

[0003] Some bodies of water are, for example, artificially constructed as retention basins along roads. These basins serve to collect the large volumes of water that occur suddenly during roadside rainfall, store them, and then slowly discharge them into a natural watercourse or a drainage system, allow them to infiltrate the ground, or release them into the atmosphere through evaporation. In this case, the retention basin also serves to retain pollutants such as tire abrasion, brake wear, oil, and dust, preventing them from reaching the natural watercourse or drainage system. Such pollutants are expected to settle in the body of water and form a layer of sediment on the bottom. The thickness of this sediment layer increases over time, reducing the volume of the body of water available to absorb the sudden influx of water.If the volume of sediment is reduced to the point that the body of water can no longer fulfill its retention function for large quantities of water produced suddenly, the sediment layer must be removed to increase the available water volume. Removing the sediment layer from a body of water involves considerable effort. For example, excavators and trucks must be brought to the water body. Therefore, sediment removal from the body of water only begins once the need for it has been established and confirmed by measurements.

[0004] Conventionally, sediment layer thicknesses and water volumes in bodies of water are determined by soundings using rods, which are carried out from boats. Such measurements are also complex, as they require the movement of one or more boats to the body of water and, to achieve the desired measurement accuracy, soundings must be carried out at a large number of locations on the body of water, these locations having to be serviced successively by the boat, which is very time-consuming. In addition, it is sometimes difficult, or even impossible, to access certain locations on the body of water by boat when this is obstructed by vegetation, such as reeds.

[0005] One problem of the present invention is to provide a method for measuring a body of water and a measurement system which simplifies the measurement of a layer of sediment at the bottom of the body of water.

[0006] To solve this problem, the present invention provides a method for measuring a body of water, which uses a drone from which a long rod is suspended. The drone, with the rod suspended, is positioned above the body of water to take measurements from which the thickness of a sediment layer deposited on the bottom of the body of water can be calculated. The method further comprises lowering the drone so that one end of the rod breaks through the water surface. The drone is then lowered further so that the other end of the rod penetrates the sediment layer on the bottom of the body of water. The drone is then lowered again, and the rod is driven into the sediment layer until a cutoff point is reached.

[0007] Alternatively, the rod may not be held on a drone but in another manner. For example, the rod may be held by a person in or on a boat who moves the boat across the body of water to position the rod at the desired location for taking measurements from which the thickness of a sediment layer deposited on the bottom of the body of water can be calculated. The method further comprises lowering the rod so that one end of the rod passes through the surface of the water. The rod is then lowered further so that its lower end penetrates the sediment layer on the bottom of the water. The rod is then lowered again and driven into the sediment layer until a stopping criterion is reached.

[0008] According to embodiments given by way of example, the length of the rod between its first end, which is attached to the drone, and its second end is greater than 1.5 m and, in particular, greater than 3 m. In this case, the second end of the rod is a thin end capable of penetrating the sediment layer. For example, the second end of the rod, at a point located 1 cm from a tip of the rod, has a cross-sectional area that is less than 120 mm², less than 60 mm², and, in particular, less than 30 mm².

[0009] Several measures can be taken during the process of lowering the rod, for example by lowering the drone, until the interruption criterion is reached.

[0010] The interruption criterion can, for example, be defined by a compressive force to be achieved, with which the rod is pushed downwards by the drone. The interruption criterion can also be defined, for example, by reaching the maximum negative lift force obtainable by the drone's aerodynamic engine. The interruption criterion can further be defined, for example, by the maximum expected flow time for penetration of the sediment layer. In addition, it is possible to measure the force exerted on the rod in its longitudinal direction, for example, by means of a strain gauge or similar device. Reaching the interruption criterion can be signaled, for example, to the person lowering the rod by the emission of an audible signal, so that this person can remove it to perform another measurement at a different location.

[0011] According to embodiments given by way of example, the method includes measuring a quantity that represents the height of the drone or rod at the location where the interruption criterion is reached. The calculation of the sediment layer thickness at the location can be performed based on the quantity measured when the interruption criterion is reached, representing the height of the drone or rod.

[0012] According to embodiments given by way of example, the method further includes a measurement of a quantity representing the height of a surface of the sediment layer at the location. The calculation of the sediment layer thickness can then be performed based on the quantity determined when the interruption criterion is reached, representing the height of the drone or rod, and the quantity representing the height of the sediment layer surface.

[0013] The measurement of the quantity representing the height of the sediment layer surface at the location may include, according to exemplary embodiments, detecting the penetration of the rod into the sediment layer using a sediment sensor and measuring a quantity representing the height of the drone at the location upon detection of the rod's penetration into the sediment layer. The sediment sensor may be provided on the rod, near its second end.

[0014] The measurement of the quantity representing the height of the surface of the sediment layer at the location may include, according to other embodiments, placing a first body that can slide along the rod on the surface of the sediment layer and measuring a quantity that represents a height of the first body placed on the surface of the sediment layer.

[0015] The first body is designed to sink into the water and has a surface facing the sediment layer that is large enough to allow it to rest on the surface of the sediment layer without penetrating too deeply into it. A pressure sensor may be provided on the first body, which measures the hydrostatic pressure of the surrounding water. The water pressure makes it possible to determine the depth of the water at the surface of the sediment layer and therefore, if the height of the water surface is known, also the height of the surface of the sediment layer.

[0016] According to other embodiments given by way of example, the method further includes a measurement of a quantity that represents a height of the water surface, and a calculation of a water depth between the water surface and the surface of the sediment layer on the basis of the quantity representing the height of the water surface.

[0017] According to embodiments given by way of example herein, the measurement of the quantity representing the height of the water surface at the location comprises detecting the penetration of the rod into the water using a water sensor and measuring a quantity representing the height of the drone or the rod at the location upon detection of the rod's penetration into the water. The water sensor may be provided on the rod, near its second end.

[0018] According to other embodiments given by way of example, the measurement of the quantity representing the height of the water surface at the location includes placing a second body that can slide along the rod on the water surface and measuring a quantity that represents a height of the second body placed on the water surface.

[0019] The second body is designed so that it floats on water.

[0020] According to embodiments given by way of example, driving the rod into the sediment layer involves applying a compressive force to the rod by at least part of the drone's weight and / or applying a compressive force to the rod by an aircraft engine of the drone. This can be achieved, for example, by reducing the lift generated by the drone's rotors and also by generating negative lift using the drone's rotors. The generation of negative lift can, for example, be achieved by reversing the direction of rotation of the rotors that normally generate lift.

[0021] In addition, it is possible to control the drone's rotors in such a way that the drone and the rod are driven in rotation around a longitudinal axis of the rod during the thrust into the sediment layer, so that the rod somehow pierces the sediment layer.

[0022] According to embodiments given by way of example, the interruption criterion is reached when a compressive force is applied to the rod by the drone or by A person holding the rod directly reaches a predetermined value. The underlying idea is that the bottom of the body of water has a significantly higher density than the sediment layer and that the compressive force required to lower the rod increases accordingly and significantly as soon as the second end of the rod reaches the bottom of the body of water.

[0023] The thickness of the sediment layer at a given location can, for example, be calculated from the difference between the height of the sediment layer surface and the height of the bottom surface. The water depth at the location can, for example, be calculated by determining the difference between the height of the water surface at the location and the height of the sediment layer surface at the location.

[0024] According to embodiments given by way of example, the method further comprises positioning the rod, for example using a drone or a boat, successively at a plurality of locations above the body of water and carrying out the measurements described above by lowering the rod to the respective location, and calculating a volume of the sediment layer and / or a volume of water on the basis of the coordinates of the locations and the thicknesses of the sediment layer and the water depths calculated at these locations.

[0025] According to exemplary embodiments, the measurement of the quantity representing the height of the rod at the location includes a measurement of the position of a signal receiver of a satellite navigation system and / or a measurement of the position of the rod using an optical measuring system positioned on the edge of the body of water. The receiver may be attached to the drone or directly to the rod.

[0026] The signal receiver of a satellite navigation system can be, for example, a GPS receiver. The optical measuring system can be, for example, a total station that directs a laser beam towards the drone or a predetermined part of the rod in order to measure the distance from the optical measuring system and that measures the horizontal and vertical angles of the drone or the predetermined part of the rod relative to the optical measuring system.

[0027] The aforementioned problem is further solved by a measurement system for measuring a body of water, the measurement system comprising a drone, an elongated rod, and a positioning system. The positioning system is configured to determine the drone's position. The elongated rod has a first end and a second end. The first end of the rod is fixed to the drone, and the second end is thin so that it can be driven into a layer of sediment. For example, the second end of the rod, at a point 1 cm from one tip of the rod, has a cross-sectional area which is less than 120 mm2, less than 60 mm2 and in particular less than 30 mm2. The measuring system may also have the properties already explained previously in relation to the process.

[0028] Embodiments of the invention are explained in more detail below with the aid of figures. In this case:

[0029] Fig. 1 illustrates a schematic representation of a measuring system according to one embodiment on a body of water in a side view;

[0030] [Fig.2] illustrates a top view of the body of water in [Fig.1];

[0031] Figure 3 illustrates a schematic representation of part of a system of measure according to another embodiment;

[0032] Figure 4 illustrates a flowchart explaining a method for measuring a body of water according to another embodiment; and

[0033] Fig. 5 illustrates a schematic representation of a measuring system according to yet another embodiment on a body of water in a side view.

[0034] Fig. 1 illustrates a schematic representation of a measuring system for measuring a body of water in a side view, and Fig. 2 illustrates the body of water in a top view. The body of water 1 is a quantity of water 5 received in a depression in the ground 3. In this case, the depression in the ground receives not only the water 5, but also a layer of sediment 7 that has been deposited on a bottom 9 of the body of water 1.

[0035] The water 5 in the depression 9 extends to a boundary line 11 which laterally delimits the body of water. In addition, an inlet 13 brings water into the body of water 1 and an outlet 15 removes water from the body of water 1. The water flowing into the body of water 1 through the inlet 13 contains suspended matter which settles on the bottom 9 of the body of water 1 and forms the sediment layer 7.

[0036] The measuring system 21 is designed to measure the thickness DI of the sediment layer 7. The measuring system 21 comprises a drone 23 which has a platform 25 on which motors 27 are provided, driving rotors 29 that generate lift in the air, so that the drone can fly and be steered in desired directions. The flight movements of the drone 23 are controlled by a user at the edge of the body of water 1, by means of a control terminal 31, such as a laptop computer, which maintains a radio link for transmitting flight movement commands from the control terminal 31 to the drone 23 and for transmitting measurement values ​​from the drone 23 to the control terminal 31.

[0037] The position of the drone 23 in space can be continuously determined. For example, the drone 23 has a GPS receiver on the platform 25 for this purpose, which receives position signals 35 from the GPS satellite navigation system, a satellite 37 of this system being schematically represented in [Fig. 1]. The position of the drone 23, measured using the GPS receiver 33, is continuously transmitted to the control terminal 31 via the radio link. The position of the drone can, for example, be indicated horizontally in x and y coordinates and vertically by a height h relative to a location on the shore or at sea level or relative to another height that can serve as a reference for height measurements within the framework of the method described herein.

[0038] As an alternative or complement to position measurement using the GPS receiver 33, the position of the drone 23 can be determined using an optical measurement system 41 comprising a total station 43 installed on the edge of the body of water. The optical measurement system further includes a reflector 45 provided on the platform 25 of the drone 23, which reflects a laser beam 47 emitted by the theodolite 43 back to the theodolite 43, so that the latter can measure the distance between the drone 23 and the theodolite 43. In addition, the theodolite 43 measures, besides the distance to the drone, angles in the vertical and horizontal directions, in order to determine the coordinates of the drone 23, only the angle α in the vertical direction being shown in [Fig. 1]. These coordinates make it possible to determine the height of the drone 23 relative to a predetermined reference height. In the description below and the representation of the [Fig.[l], the heights are measured relative to the height of the total station 4L II. However, it is also possible to convert the respective heights to height above sea level, which is often used.

[0039] For the measurement of the volume of the sediment layer 7 in the body of water, the drone 23 is piloted successively to a plurality of locations 51 (cf. [Fig.2]) above the body of water, and the thickness of the sediment layer 7 is determined at each of the locations 51.

[0040] To this end, the measuring system 21 comprises an elongated rod 53 having a first upper end 54 and a second lower end 55. By the first end 54, the rod is fixed to the platform 25 of the drone 23 such that the rod is suspended from the drone 23. A length of the rod between the first end 54 and the second end 55 is, for example, 2 m, 3 m, 5 m or more. Furthermore, in the region of its second end 55, the rod is a thin rod having a cross-sectional area of ​​less than 120 mm², less than 60 mm², or less than 30 mm².

[0041] The connection of the first end 54 of the rod 53 to the drone 23 may further include a joint, not shown in [Fig. 1], which allows pivoting of the rod 53 relative to the drone 23, one or more springs being provided for example to maintain the orientation of the rod relative to the drone 23 in a preferred orientation, and a damping mechanism being provided between the rod 53 and the drone 23, which dampens vibrations of the rod 53 relative to the drone 23. Such a damped articulated suspension of the rod can advantageously influence the aerodynamic properties of the drone.

[0042] At the start of a measurement, the drone 23 is brought to a selected location 51, the second end 55 of the rod 53 being positioned above a water surface 57 of the body of water 1. Then, the drone 23 is lowered so that the second end 55 of the rod 53 passes through the water surface 57. The drone 23 is then lowered further, so that the second end 55 of the rod 53 penetrates the sediment layer 7. The drone is lowered further until the rod 53 passes through the sediment layer 7 and its lower end 55 rests on the bottom 9 of the body of water 1. As soon as the lower end 55 of the rod 53 rests on the bottom 9, the drone cannot be lowered any further, because the bottom 9 of the body of water 1 presents a high resistance, so that the Rod 53 cannot penetrate further. In this situation, shown in [Fig. 1], the height h of drone 23 is measured.If the length of the rod 53 is known, this also allows us to determine the height H1 of the bottom 9 of the body of water 1 at location (x, y).

[0043] If simply lowering the drone 23 does not allow easy penetration of the sediment layer 7, various measures can be adopted to penetrate the sediment layer 7. For example, the flight movements of the drone 23 are controlled so as to rotate the rod 53 around its longitudinal axis in order to pierce the sediment layer 7 with the rod 53. In addition, a mechanism that generates vibrations of the rod 53 or exerts shocks on the rod can be provided on the drone 23, which shocks or vibrations facilitate penetration of the sediment layer 7.

[0044] An inclination sensor can also be attached to the rod 53, the measurement values ​​of which are taken into account when controlling the drone 23 during lowering, in order to maintain the rod 53 in a substantially vertical orientation.

[0045] The drone's descent is complete when an interruption criterion is met. In the example described here, the interruption criterion is defined by the value of a compressive force exerted by the drone 23 on the rod 53. This compressive force is measured by a force sensor 52, which is provided at the junction between the platform 25 of the drone 23 and the upper end 54 of the rod 53. The force sensor 52 may, for example, comprise a spring whose length varies as the force exerted by the drone 23 on the rod 53 increases. It is then possible to monitor the length of the spring to determine whether the interruption criterion has been met.

[0046] When determining the interruption criterion, other measurement values ​​may be taken into account in addition to force. For example, the increase in applied force over time may be recorded and taken into account when determining the interruption criterion.

[0047] A float 61 is attached to the rod 53 so that it can slide along the longitudinal direction of the rod 53. When the lower end 55 of the rod 53 passes through the surface of the water 57 during lowering, the float 61 floats on the surface of the water. The position of the float 61 along the length of the rod 53 can, for example, be determined by analyzing images taken by a camera 63 mounted on the platform 25 of the drone 23. In this way, it is possible to determine the height H2 of the water level 57.

[0048] Alternatively, the height of the water level 57 can also be determined by a single measurement, for example using the total station 4L. The result of this height measurement can then be used as the height H2 of the water level 57 in measurements at all locations 51.

[0049] A submersible body 65 is further provided on the rod 53 and can be moved in the longitudinal direction of the rod. The submersible body 65 is submerged in the water and has a large downward-facing frontal surface, so that the submersible body 65 remains on a surface 67 of the sediment layer 7 when the rod 53 penetrates the sediment layer 7. A pressure sensor 69 is attached to the submersible body 65, which measures the hydrostatic pressure of the water 5 surrounding the pressure sensor 69 and transmits it immediately or subsequently to the drone 23 or the terminal 31. Knowing the height H2 of the water surface 57, the height H3 of the surface 67 of the sediment layer 7 can be determined from the measured pressure.

[0050] The thickness DI of the sediment layer 7 and the water depth D2 can be determined from the quantities H1, H2 and H3 thus determined.

[0051] This determination is repeated at all locations 51. The volume of the sediment layer 7 can then be approximately determined from the thicknesses DI of the sediment layer 7 at the different locations. In addition, the volume of water in the water body 1 can be approximately determined from the water depths D2 measured at the different locations. If the water volume is less than a certain limit value and / or if the volume of the sediment layer 7 exceeds a certain limit value, it may be decided to remove the sediment layer 7 from the water body, the measured volume of the sediment layer 7 allowing the necessary logistical measures to be planned.

[0052] In certain situations, it may be difficult, or even impossible, to extract the stem 53 from the sediment layer 7 again by the force of the drone 23. In such cases, a The mechanism provided on the drone 23 can be activated, which detaches the rod 53 from the drone 23. The drone 23 can then complete its flight in an orderly manner, before a battery providing energy is, for example, exhausted, and the rod 53 can be recovered later using a boat.

[0053] In the measuring system 23 explained with the aid of [Fig. 1], the height H2 of the water level 57 is determined with the aid of the floating body 61, and the height H3 of the surface 67 of the sediment layer 7 is determined with the aid of the submerging body 65.

[0054] The float 61 is also useful for providing a visual reference point, observation of which by the camera 63 or directly by the user's eye can help to control the drone 23.

[0055] Figure 3 schematically represents a partial view of a measuring system 23a according to another embodiment, allowing the height H2 of the water level 57 and the height H3 of the surface 67 of the sediment layer 7 to be determined alternatively. The measuring system 23a also includes a drone, which is not shown in Figure 3. Figure 3 illustrates only a lower end 55a of a rod 53a suspended from the drone. The rod 53a is thin in the region of its lower end 55a, in that it has a cross-sectional area Q that is less than 120 mm², less than 60 mm², or less than 30 mm² at a point located 1 cm from a tip 56 of the rod 53a.

[0056] In the region of the lower end 55a of the rod 53a, an optical sensor 71 is provided in the rod 53a, which serves as a water sensor and a sediment sensor. The sensor 71 comprises a light source 73, a light detector 75, and a window 77. The light source 73 emits light towards the window 77, and the light detector 75 detects the light coming from the window 77. When the sensor 71 is disposed in air, a large part of the light emitted by the light source 77 towards the window 77 is reflected at the outer surface of the window 77, as schematically represented by a light beam 79 in [Fig. 3]. In this case, the light detector 75 detects a large amount of light.

[0057] When the sensor 71 enters the water, a smaller portion of the light emitted by the light source 73 is reflected at the window 77, while a larger portion of the light leaves the sensor 71 through the window 77, as schematically represented by a light beam 81 in [Fig. 3]. The light detector 75 therefore detects less light, and the decrease in light intensity detected during the drone's descent allows us to conclude that the lower end 55a of the rod 53a has just crossed the water's surface. By measuring the drone's height at this instant, it is possible to determine the height of the water's surface, given that the length of the rod 53a is known.

[0058] When the sensor 71 penetrates the sediment layer 7, the sediment particles 83 surrounding the sensor 71 reflect the light back towards the window 77, which light finally reaches the light detector 75, as represented by a light beam 85 by way of example. The corresponding increase in light intensity detected during the drone's descent thus allows us to conclude that the lower end 55a of the rod 53a has penetrated the surface 67 of the sediment layer 7. In this situation, it is then possible to determine the height of the surface of the sediment layer 7 by measuring the height of the drone, the length of the rod 53a being known.

[0059] The sensor 71 described here is only one example of a water sensor configured to detect the presence of water in the sensor's environment, and of a sediment sensor configured to detect the presence of sediment in the sensor's environment. Other possibilities for providing a water sensor and a sediment sensor are conceivable. For example, the presence of water on the sensor can be detected by measuring the electrical conductivity between two electrodes attached to the sensor and spaced apart. The presence of sediment at the sensor can, for example, be detected by measuring the ambient light intensity, for example using a phototransistor, if the measurements are taken in daylight and at a water depth shallow enough that the sensor detects light while surrounded by water and does not detect light once it has penetrated the sediment.

[0060] The method for measuring the water body is summarized again with reference to the flowchart in [Fig. 4]. In step 91, the drone is positioned at a location (x, y) above the water body. Then, the drone is lowered in step 92, and its height is determined when the rod enters the water. Next, the drone is lowered further in step 93, and its height is detected as soon as the rod enters the sediment. The drone is then lowered further in step 94, and the height of the drone is determined when the lower end of the rod touches down on the bottom 9 of the body of water 1. In step 95, the thickness of the sediment layer 7 and the water depth 5 at location (x, y) can then be determined based on the measurements taken in steps 92, 93, 94.

[0061] A subsequent location (x, y) is then selected, and steps 91 to 95 are performed for this subsequent location. This process is repeated until the thickness of the sediment layer 7 and the water depth are determined at all desired locations. Then, in step 96, the volume of the sediment layer 7 and the volume of the water 5 can be calculated approximately.

[0062] Fig. 5 illustrates a schematic representation of another embodiment of a measuring system for measuring a body of water in a side view.

[0063] In the embodiment illustrated in [Fig. 5], an elongated rod 53b for taking measurements is not held by a drone but by a person 101 located in or on a boat 103 floating on a body of water 1. The boat 103 is propelled by a motor (not shown in [Fig. 5]) or by oars operated by the person 101. The person 101 steers the boat 103 so that the rod 53b, held vertically by the person 101, reaches a desired location 51. Then, the person 101 lowers the rod 53b so that a lower end 55b of the rod 53b passes through a surface of the water 57b of the body of water 1b. Next, person 101 lowers the rod 53b further, so that the lower end 55b of the rod 53b penetrates a layer of sediment deposited on a bottom of the body of water 1.Next, person 101 continues to lower rod 53b and push it into the sediment layer until a stopping criterion is reached.

[0064] The crossing of the water surface 57b of the water body 1b, the penetration into the sediment layer and the attainment of the interruption criterion can be detected by sensors, as previously described.

[0065] When the crossing of the water surface 57b of the water body 1b, penetration into the sediment layer, or reaching the interruption criterion is detected, the height of the rod 53b is measured each time. For this purpose, the rod 53b has, for example, a GPS receiver 33b which is attached to an upper end 54b of the rod 53b. Alternatively, a reflector can also be attached to it in order to determine the position of the rod 53b using an optical measuring system.

[0066] The thickness of the sediment layer at location 51 can be calculated from the detected height of the rod 53b when the interruption criterion is reached and the detected height of the rod 53b when its lower end penetrates the sediment layer. The water depth at location 51 can be determined from the detected height of the rod 53b when its lower end penetrates the sediment layer and the detected height of the rod 53b when it passes through the water surface 57b. In this case, it is not necessary to re-determine the height of the water surface 57b at each location 51, as it is identical at all locations 51. When the interruption criterion is reached, a sound signal can for example be emitted, which the person 101 can perceive and which can be the occasion to move the rod 53b with the boat 103 to a next location 51.

[0067] As an alternative to the embodiment explained with reference to [Fig. 5], it is possible, in another embodiment, that instead of a person holding the rod, a mechanical device is attached to the boat and raises and lowers the rod. using a motor. The boat and the motor form a movement system which is remotely controlled, so that the boat successively positions the rod at the desired location and the motor moves the rod up and down to the respective locations, in order to implement the process explained above.

[0068] Alternatively, it is also possible to fix the rod to a moving device fixed to a bank, such as a crane, and to position the rod at the various desired locations 51 by actuation of the moving device and to implement the process explained above.

Claims

Demands

1. A method for measuring a body of water, the method comprising: positioning an elongated rod (53), having a first end (54) and a second end (55), at a location (51) above the body of water (1) such that the rod (53) is oriented substantially perpendicular to a water surface (57) of the body of water (1); lowering the rod (53) such that the second end (55) of the rod (53) passes through the water surface (57) of the body of water (1); further lowering the rod (53) such that the second end (55) of the rod (53) penetrates a layer of sediment (7) deposited on a bottom (9) of the body of water (1); the further lowering of the rod (53) and the pushing of the rod (53) into the sediment layer (7) until an interruption criterion is reached;the measurement, during the lowering of the rod (53), of a quantity that represents a height (H3) of a surface (67) of the sediment layer (7) at the location (51); the measurement of a quantity that represents a height (h) of the rod at the location (51) when the interruption criterion is reached; and the calculation of a thickness (Dl) of the sediment layer (7) at the location (51) on the basis of the quantity representing the height, measured when the interruption criterion is reached, of the rod (53) and the quantity representing the height of the surface (67) of the sediment layer (7).

2. Method according to claim 1, wherein the rod (53) is held on a drone (23).

3. A method according to claim 2, wherein the thrust of the rod (53) into the sediment layer (7) comprises: the supply of a compressive force on the rod by at least a part of a weight of the drone (23); and / or the supply of a compressive force on the rod by an aircraft engine (27) of the drone (23).

4. Method according to claim 1, in which the rod (53b) is held on a boat (103).

5. A method according to any one of claims 1 to 4, wherein the measurement of the quantity representing the height (H3) of the surface (67) of the sediment layer (7) at location (51) comprises: detecting the penetration of the rod (53a) into the sediment layer using a sediment sensor (71); and measuring a quantity that represents the height (h) of the rod at location (51) upon detection of the penetration of the rod (53a) into the sediment layer (7).

6. A method according to any one of claims 1 to 5, wherein the measurement of the quantity representing the height (H3) of the surface (67) of the sediment layer (7) at the location (51) comprises: placing a first body (65) that can slide along the rod (53) on the surface (67) of the sediment layer (7); and measuring a quantity that represents a height (H3) of the first body (65) placed on the surface (67) of the sediment layer (7).

7. A method according to any one of claims 1 to 6, further comprising measuring a quantity that represents a height (H2) of the water surface (57); and calculating a water depth (D2) between the water surface (57) and the surface (67) of the sediment layer (7) on the basis of the quantity representing the height (H2) of the water surface (57).

8. A method according to any one of claims 1 to 7, wherein the measurement of the quantity representing the height (H2) of the water surface at location (51) comprises: detecting the penetration of the rod (53a) into the water using a water sensor (71); and measuring a quantity that represents the height (h) of the drone at location (51) upon detection of the penetration of the rod (53a) into the water.

9. A method according to any one of claims 1 to 7, wherein the measurement of the quantity representing the height (H2) of the water surface (57) at the location (51) comprises: placing on the water surface (57) a second body (61) capable of sliding along the rod (53); and the measurement of a quantity which represents a height (H2) of the second body (61) placed on the surface of the water (57).

10. A method according to any one of claims 1 to 9, wherein the thrust of the rod (53) comprises a rotation of the rod (53) about its longitudinal axis.

11. A method according to any one of claims 1 to 10, wherein the interruption criterion represents an attainment of a predetermined compressive force on the rod.

12. A method according to any one of claims 1 to 11, further comprising: positioning the rod successively at a plurality of locations (51) above the body of water (1) and calculating the thickness (Dl) of the sediment layer at each location (51) of the plurality of locations (51); and calculating a volume of the sediment layer (7) on the basis of coordinates (x, y) of the locations (51) of the plurality of locations (51) and the thicknesses (Dl) of the sediment layer calculated at the plurality of locations (51).

13. A method according to any one of claims 1 to 12, wherein the measurement of the quantity representing the height (h) of the rod at location (51) comprises: the measurement of a position of a receiver (33), connected to the rod, of signals from a satellite navigation system (37); and / or the measurement of a position of the rod using an optical measuring system (43) positioned on an edge of the body of water.

14. A measuring system for measuring a body of water, the measuring system comprising: a displacement system (23); an elongated rod (53) having a first end (54) and a second end (55) opposite the first end (54), the first end (54) of the rod (53) being fixed to the displacement system (23); and a positioning system (33, 37, 43) configured to determine a position (x, y, h) of the rod (53) on the displacement system (23); wherein the second end (55) of the rod (53) has, at a point 1 cm from a tip (56) of the rod, a cross-sectional area transverse which is less than 120 mm2, less than 60 mm2 and in particular less than 20 mm2.

15. A measuring system according to claim 14, wherein the rod (53) has a length greater than 1.5 m, and in particular greater than 3 m. 116 A measuring system according to claim 14 or 15, further comprising: a sediment sensor (71) which is fixed to the rod (53a) and which is configured to detect a penetration of the rod (53a) into sediments (7) of the body of water (1).

17. A measuring system according to any one of claims 14 to 16, further comprising: a water sensor (71) which is fixed to the rod (53a) and which is configured to detect a penetration of the rod (53a) into water (5) of the body of water (1).

18. A measuring system according to any one of claims 14 to 17, further comprising: a first body (65) fixed to the rod (53) and capable of sliding in the longitudinal direction thereof, which is configured to be submerged in water (5).

19. Measurement system according to claim 18, further comprising a pressure sensor (69) which is provided on the first body (65).

20. A measuring system according to any one of claims 14 to 19, further comprising: a second body (61) fixed to the rod (53) and capable of sliding in the longitudinal direction thereof, which is configured to float on water (5).

21. A measuring system according to any one of claims 14 to 20, further comprising: a force sensor (52) which is configured to measure a force acting in the longitudinal direction of the rod (53).

22. A measuring system according to any one of claims 14 to 21, wherein the displacement system comprises a drone.

23. A measuring system according to any one of claims 14 to 21, wherein the displacement system comprises a boat (103).

24. A measuring system according to any one of claims 14 to 23, the measuring system being configured to implement the method according to any one of claims 1 to 13.

25. A measuring system for measuring a body of water, the measuring system comprising: an elongated rod (53) having a first end (54) and a second end (55) opposite the first end (54); a positioning system (33, 37; 43) having a component that is permanently attached to the rod, the positioning system being configured to determine a position (x, y, h) of the rod; a sediment sensor (71) that is attached to the rod (53a) and that is configured to detect a penetration of the rod (53a) into sediments (7) of the body of water (1); and / or a first body (65) attached to the rod (53) and capable of sliding in the longitudinal direction thereof, which is configured to be submerged in the water (5).

26. Measurement system according to claim 25, further comprising a pressure sensor (69) which is provided on the first body (65).

27. ​​A method for measuring a body of water, in particular using the measuring system according to any one of claims 25 and 26, the method comprising: positioning an elongated rod at a location (51) above the body of water (1) such that the rod is oriented substantially perpendicular to a surface of the body of water; lowering the rod so that a lower end (55) of the rod (53) passes through a surface of the water (57) of the body of water (1); further lowering the rod so that the lower end (55) of the rod (53) penetrates a layer of sediment (7) deposited on a bottom (9) of the body of water (1); further lowering of the rod and pushing the rod (53) into the layer of sediment (7) until an interruption criterion is reached; the measurement of a quantity that represents a height (H3) of a surface (67) of the sediment layer (7) at location (51); the measurement, during the lowering of the rod (53), of a quantity that represents a height (h) of the rod at location (51) when the interruption criterion is reached; and the calculation of a thickness (Dl) of the sediment layer (7) at location (51) based on the quantity representing the height of the stem, measured when the interruption criterion is reached.

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