Autonomous agricultural vehicle comprising a hydrogen-powered main propulsion system

Abstract

The present invention relates to an autonomous agricultural vehicle (1) comprising a framework (2) and wheels (3), the framework (2) having a width, two flanks, one on each side of a longitudinal axis (X) of the autonomous agricultural vehicle (1), and a top, at least one tool being able to be housed in a working volume (20) defined by the width and the top of the framework (2), the autonomous agricultural vehicle (1) moreover comprising a hydrogen-powered propulsion system comprising at least one hydrogen fuel cell (100). The autonomous agricultural vehicle according to the invention moreover comprises at least one hydrogen cylinder (11, 12) positioned longitudinally on the top of the framework (2), the hydrogen fuel cell (100) being configured to consume hydrogen from the at least one hydrogen cylinder (11, 12) and oxygen captured from the air so as to supply electrical power to an electric motor of the hydrogen-powered propulsion system.

Description

Autonomous agricultural machinery including a hydrogen-powered main drive system

[0001] The present invention relates to the field of agricultural machinery, in particular autonomous agricultural robots. More specifically, the present invention relates to an autonomous agricultural machine comprising a hydrogen main drive system. STATE OF THE ART

[0002] In the field of agricultural machinery, autonomous vehicles have been developed. These autonomous agricultural machines, also known as agricultural robots, are suitable for working on open-field crops, for example in vineyards, in a fully or partially autonomous manner.

[0003] These autonomous agricultural machines do not carry a driver. For example, such autonomous agricultural machines may carry one or more tools intended for working the soil, maintaining the soil or maintaining vines, for example one or more tools for trimming vines, or one or more tanks containing active products to be delivered to crops, for example vines. Such autonomous agricultural machines, less bulky than agricultural machines carrying a driver, if only because they do not include a driver's cabin or a system intended to protect or improve the comfort of the driver (air conditioning, cabin air filter, etc.), are particularly suitable for working in narrow vineyard plots.

[0004] Currently, autonomous agricultural machinery features electric drive systems powered by high-voltage batteries or thermal engines.

[0005] For example, document IN 202141057703 A is known, which describes a remotely controlled agricultural machine suitable for spraying crops. The objective here is to protect the farmer from the possible toxicity of the sprayed active products. To this end, the farmer disembarks and remotely controls the agricultural machine. The remotely controlled agricultural machine described in document IN 202141057703 A includes an electric motor system based on the use of lithium-ion batteries placed on top of the machine, on either side of an active product tank.

[0006] The present invention relates to an autonomous agricultural machine having a hydrogen power system. The hydrogen power systems comprise at least one electric motor supplied with energy, in particular electrical energy, by at least one hydrogen fuel cell whose function is to produce electrical energy from hydrogen and oxygen, the hydrogen being stored in tanks also called cylinders and the oxygen being conventionally captured in the surrounding outside air. It should be noted that, usually, in the context of the present invention, "hydrogen" means the chemical compound of molecular formula H2, also called dihydrogen, in particular in gaseous form; similarly, "oxygen" means the chemical compound of molecular formula O2, also called dioxygen, in particular in gaseous form, present in the outside air.

[0007] As is well known, hydrogen powertrain systems therefore require the presence of at least one hydrogen cylinder, particularly in gaseous form. Such tanks are heavy and bulky.

[0008] In this context, the present invention relates to an autonomous agricultural machine comprising a hydrogen engine system, with hydrogen cylinders arranged on top of the frame of the machine. It should be noted that it is a priori counterintuitive for those skilled in the art to place such hydrogen cylinders on top of the machine because they would assume that, to improve stability, it is better to place the cylinders on the sides. PRESENTATION OF THE INVENTION

[0009] More specifically, the subject of the invention is an autonomous agricultural machine comprising a frame, wheels, the frame having a width, two sides on either side of a longitudinal axis of the autonomous agricultural machine and a top, at least one tool being able to be received in a useful volume defined by the width and the top of the frame, the autonomous agricultural machine further comprising a hydrogen motorization system comprising at least one hydrogen fuel cell. The autonomous agricultural machine according to the invention is remarkable at least in that it comprises at least one hydrogen cylinder arranged longitudinally on the top of the frame, the hydrogen fuel cell being configured to consume hydrogen from the at least one hydrogen cylinder and oxygen captured in the air so as to supply electrical energy to an electric motor of the hydrogen motorization system.

[0010] This makes autonomous agricultural machinery with a hydrogen power system safer. Furthermore, the invention allows the use of hydrogen cylinders of different sizes.

[0011] In particular, the at least one hydrogen cylinder is arranged longitudinally on top of the frame.

[0012] In addition, the frame comprises two transverse beams fixed on two longitudinal beams, the at least one hydrogen cylinder resting by its ends and being fixed on the two transverse beams.

[0013] According to one embodiment, the autonomous agricultural machine according to the invention comprises two hydrogen cylinders arranged longitudinally on top of the frame parallel to each other, on either side of the longitudinal axis of the autonomous agricultural machine.

[0014] Advantageously, the distance between the two transverse beams, along the longitudinal axis, is adjustable.

[0015] According to one embodiment, the hydrogen fuel cell powers a power architecture comprising, in addition to the electric motor, a plurality of other electrical devices. In particular, the hydrogen fuel cell can also supply electrical energy to one or more electrical devices of the autonomous agricultural machine, among: one or more electrical power converters; one or more batteries; one or more computers.

[0016] According to one embodiment, the autonomous agricultural machine according to the invention comprises at least one battery, in particular a lithium-ion battery, arranged on a side of the frame and fixed to the latter.

[0017] According to one embodiment, the autonomous agricultural machine according to the invention comprises at least one air filter adapted to extract oxygen from the air and at least one computer arranged on a side of the autonomous agricultural machine, and being configured to control the admission of hydrogen from the at least one hydrogen and oxygen cylinder, obtained via the air filter, into the at least one hydrogen fuel cell, to produce a quantity of electrical energy powering the electric motor of the hydrogen power system.

[0018] According to one embodiment, the autonomous agricultural machine according to the invention comprises at least one tank configured to comprise an active product and means for spraying the active product arranged in the useful volume, substantially in a longitudinal median plane of the autonomous agricultural machine.

[0019] According to one embodiment, the autonomous agricultural machine according to the invention further comprises containment panels arranged on the sides of the autonomous agricultural machine and configured to block the diffusion of active product towards the outside of the useful volume.

[0020] According to one embodiment, the autonomous agricultural machine according to the invention further comprises one or more tools intended for working the soil, maintaining the soil or maintaining vines, for example one or more tools for trimming vines. PRESENTATION OF FIGURES

[0021] The invention will be better understood on reading the following description, given solely by way of example, and referring to the appended drawings given as non-limiting examples, in which identical references are given to similar objects and in which:

[0022] This is a schematic front representation of an autonomous agricultural machine including a hydrogen powertrain system;

[0023] This is a schematic representation of another example of autonomous agricultural machinery according to the invention, in isometric view;

[0024] Corresponding to an isometric view of the autonomous agricultural machine of the, showing the side opposite to that visible on the.

[0025] It should be noted that the figures set out the invention in detail to enable the invention to be implemented; although not limiting, said figures serve in particular to better define the invention where appropriate. DETAILED DESCRIPTION OF THE INVENTION

[0026] The invention relates to an autonomous agricultural machine 1 comprising a main hydrogen engine system.

[0027] In particular, as in the, such an autonomous agricultural machine 1 may consist of a vineyard robot configured to carry out the treatment of a row of vines spanned by the body of the vineyard robot.

[0028] The treatment may consist of working the soil, maintaining the soil, trimming or spraying an active product, particularly in a so-called confined manner.

[0029] The autonomous agricultural machine 1 according to the invention is equipped with a hydrogen engine system.

[0030] With reference to the, the autonomous agricultural machine 1 according to the invention comprises a frame 2. In particular, the frame 2 defines a substantially parallelepipedal useful volume 20 with a frame, in particular metallic, having two sides which rest, via suspensions, on two pairs of independent wheels. In the useful volume 20 defined by the width between the wheels 3 on either side of a longitudinal axis X of the autonomous agricultural machine 1 and a corresponding upper plane above the frame 2, tools can be installed.

[0031] For example, on the, a soil working tool is installed. In the useful volume, a tool holder 23 is installed. On this tool holder 23, a soil working tool 24 is fixed, the soil working tool 24 comprising blades 240 intended to enter the soil to work it.

[0032] The hydrogen electric drive system of the autonomous agricultural machine 1 is in particular connected to at least one hydrogen cylinder 11, 12 forming a hydrogen gas tank. Preferably, the autonomous agricultural machine 1 according to the invention has two hydrogen cylinders 11, 12, as in the example shown in Figures 1 to 3.

[0033] For example, the electric motor system comprises an electric motor powered by at least one hydrogen fuel cell 100 drawing hydrogen fuel from the hydrogen cylinders 11, 12, and oxygen from the air via an air filter 101. The hydrogen fuel cell 100 is visible on the. Below the latter, an exhaust device 102 of the hydrogen fuel cell 100 is provided, as shown on the.

[0034] In addition to the electric motor, the hydrogen fuel cell 100 can also supply electrical energy to other electrical equipment of the autonomous agricultural machine 1, forming, with the electric motor, a power architecture of the autonomous agricultural machine 1. Among the electrical equipment capable of being supplied with electrical energy by the hydrogen fuel cell 100, mention may be made of: one or more electrical power converters, one or more batteries or one or more computers, for example.

[0035] According to the invention, the hydrogen cylinders 11, 12 are arranged on top of the frame 2, and not on the sides. In particular, the hydrogen cylinders 11, 12 are supported by the frame 2 comprising transverse beams 21 and / or longitudinal beams 22, or even orthogonal beams (not shown) to the longitudinal axis X of the frame 2.

[0036] By positioning the hydrogen cylinders 11, 12 on top of the frame 2, it is ensured, according to the invention, that hydrogen cylinders 11, 12 of different sizes can be used, in particular longer than those shown on the or the, without impacting the shape or the structure of the frame 2. The hydrogen cylinders 11, 12 can in fact be supported by the frame 2 while "protruding" more or less on either side. In addition, by placing the hydrogen cylinders on the sides, a disadvantage would result from a more restrictive limitation of the diameter of the hydrogen cylinders, at the risk of causing a greater laterally significant bulk, which can be prohibitive in the case where the autonomous agricultural machine is used in vineyards, the spacing between the rows of vines being limited. The positioning of the hydrogen cylinders 11, 12 on top of the frame 2, in accordance with the invention, makes it possible to overcome this potential drawback.

[0037] More specifically, with reference to and to, the hydrogen cylinders 11, 12 rest directly on the transverse beams 21 to which they are fixed by their ends. The transverse beams 21 rest on the longitudinal beams 22, to which they are fixed. According to this embodiment, there is therefore no mechanical contact between the hydrogen cylinders 11, 12 and the longitudinal beams 22. In this example shown in all the figures, the hydrogen cylinders 11, 12 are arranged longitudinally and rest on transverse beams 21 which are fixed on longitudinal beams 21. However, a corresponding arrangement, not shown, consists of arranging the hydrogen cylinders on top of the frame 2, transversely. In this case, they rest, in a similar manner, on longitudinal beams which are fixed on transverse beams.Everything described below with reference to Figures 1 to 3, concerning the longitudinal arrangement of the hydrogen cylinders 11, 12 and the characteristics of the longitudinal beams 21 supporting transverse beams 22, applies mutatis mutandis to the case where the hydrogen cylinders are arranged transversely and where transverse beams support longitudinal beams to which said hydrogen cylinders are fixed.

[0038] According to the preferred embodiment shown, the distance, along the longitudinal axis X of the frame 2, between the transverse beams 21, is adjustable. Thus, the distance between the transverse beams 21, at the front and at the rear of the frame 2, can be adapted to different lengths of hydrogen cylinders 11, 12. For example, one or the other of the transverse beams 21, or both transverse beams 21 are configured to be able to be translated on the longitudinal beams 22, along the direction of the longitudinal axis X, in order to be fixed to the longitudinal beams 22. As a result, depending on the location chosen to fix the transverse beams 21, the latter can be at different distances from each other.To this end, facing holes 220 may be provided at different levels on the longitudinal beams 22, the holes 220 being intended to receive fixing screws for fixing the transverse beams 21 to the longitudinal beams 22. Rather than hole 220 / screw pairs, other fixing means may be prepositioned at different levels on the longitudinal beams 22, such as rectangular openings into which lugs provided on the transverse beams 21 can be clipped.

[0039] This additional advantage is also linked to the fact of arranging the hydrogen cylinders 11, 12 on top of the frame 2. The frame 2 is notably made of metal, for example steel. Its shape and its volumes are configured so as not to create a cavity likely to receive and store hydrogen escaping from the hydrogen cylinders 11, 12.

[0040] By this arrangement, the hydrogen cylinders 11, 12 are arranged securely. In the event of the autonomous agricultural machine 1 overturning onto a side, for example due to uneven terrain or a particular terrain topology (slope), the hydrogen cylinders 11, 12 are thus spared and do not risk being damaged. Above all, in the event of overturning onto a side, a damaged hydrogen cylinder, from which hydrogen would escape, is avoided being trapped under the frame and under the agricultural machine, which could generate the creation of pockets of hydrogen confined under pressure, inducing a significant danger. Indeed, hydrogen is a light and very volatile gas. Thus, in the event of a leak, the general behavior of the hydrogen will be to seek to go upwards. With the hydrogen cylinders 11, 12 on top, even if the autonomous agricultural machine 1 tips over on its side, there is no obstacle to block the hydrogen escape.

[0041] The connectors connecting the hydrogen cylinders 11, 12 to the hydrogen fuel cell 100 via pipes are preferably also arranged mainly on top of the frame 2 and therefore arranged securely, the connectors not being likely to be damaged in the event of the autonomous agricultural machine 1 being overturned onto the side.

[0042] The risk of damage to the hydrogen cylinders 11, 12 in the event of the autonomous agricultural machine 1 tipping over onto a side is thus greatly reduced and the escape of hydrogen in the event of the autonomous agricultural machine 1 tipping over onto a side is not hindered. The safety of use of the autonomous agricultural machine 1 provided with a hydrogen power system is consequently improved. It should be noted that this advantage also applies when the machine does not tip over: for example, in the event of a hydrogen leak at the cylinders 11, 12 or at the pipe between the cylinders 11, 12 and the hydrogen fuel cell 100, or at connections between the cylinders 11, 12 and said pipes, the hydrogen can easily escape upwards.

[0043] Another advantage of the arrangement on top of the hydrogen cylinders 11, 12 lies in the fact that the tools arranged in the useful volume 20 are easily accessible. In particular, according to one embodiment, the autonomous agricultural machine 1 performs a spraying function. In this case, the spraying tunnel corresponds to the useful volume 20, between the pairs of wheels 3 and the top of the frame 2, and containment walls are advantageously arranged on the sides. It is noted that this confined spraying function would not be possible if the hydrogen cylinders 11, 12 were arranged on the sides because there would not be the possibility of placing containment panels on the sides since the latter would be occupied by hydrogen cylinders.

[0044] The same applies when the autonomous agricultural machine 1 performs a trimming function: the trimming tool also requires space on the sides of the machine.

[0045] According to one embodiment, one or more lithium-ion batteries 31 may be arranged on the sides of the autonomous agricultural machine 1 to power auxiliary electrical systems of the machine and / or to provide additional energy to the autonomous agricultural machine 1, in particular to the motorization system, in the event of a power peak necessary for the operation of the machine.

[0046] A computer 5 coupled to a controller 6 can also be arranged, in particular near the controller 6, on a side of the autonomous agricultural machine 1, to control the autonomous agricultural machine 1.

[0047] A computer 50 for managing the hydrogen fuel cell 100 is dedicated to controlling the hydrogen fuel cell 100. In particular, the computer 50 for managing the hydrogen fuel cell 100 manages the production of electricity, depending on the power requirements of the autonomous agricultural machine 1. Another computer, for example, can manage the admission, into the hydrogen fuel cell 100, of hydrogen from the hydrogen cylinders 11, 12 and oxygen captured from the air.

[0048] Under the hydrogen cell 100, an exhaust 102 is configured to evacuate the water produced during the production of electricity from hydrogen and oxygen. The autonomous agricultural machine 1, as shown in the, may further have an oil tank 4 which may be arranged on a side of the machine, the oil being intended to be used for the autonomous agricultural machine 1 and its tools.

Claims

An autonomous agricultural machine (1) comprising a frame (2), wheels (3), the frame (2) having a width, two sides on either side of a longitudinal axis (X) of the autonomous agricultural machine (1) and a top, at least one tool that can be received in a usable volume (20) defined by the width and the top of the frame (2), the autonomous agricultural machine (1) further comprising a hydrogen propulsion system comprising at least one hydrogen fuel cell (100), characterized in that it comprises at least one hydrogen cylinder (11, 12) arranged longitudinally on the top of the frame (2), the frame further comprising two transverse beams (21) fixed to two longitudinal beams (22), the at least one hydrogen cylinder resting by its ends on and being fixed to the two transverse beams (21), the hydrogen fuel cell (100) being configured to consume hydrogen from at least one hydrogen cylinder (11,12) and oxygen captured from the air to supply electrical energy to an electric motor of the hydrogen propulsion system. Autonomous agricultural machine (1) according to claim 1, comprising two hydrogen cylinders (11, 12) arranged longitudinally on top of the frame (2) parallel to each other, on either side of the longitudinal axis (X) of the autonomous agricultural machine (1). Autonomous agricultural machine (1) according to claim 2, wherein the distance between the two transverse beams (21), along the longitudinal axis (X), is adjustable. Autonomous agricultural machine (1) according to any one of the preceding claims, wherein the hydrogen fuel cell (100) also supplies electrical energy to one or more electrical equipment of the autonomous agricultural machine (1), including: one or more electrical power converters; one or more batteries; one or more computers. Autonomous agricultural machine (1) according to any one of the preceding claims, comprising at least one battery (31), in particular a lithium-ion battery, disposed on a side of the frame (2) and fixed to the latter. Autonomous agricultural machine (1) according to any one of the preceding claims, comprising at least one air filter (101) adapted to filter air and at least one computer (50) disposed on a side of the autonomous agricultural machine (1), and being configured to control the admission of hydrogen from at least one hydrogen cylinder (11, 12) and oxygen, obtained via the air filter (101), into at least one hydrogen fuel cell (100), to produce a quantity of electrical energy powering the electric motor of the hydrogen drive system. Autonomous agricultural machine (1) according to any one of the preceding claims, comprising at least one tank configured to include an active product and means for spraying the active product arranged in the useful volume (20), substantially in a longitudinal median plane of the autonomous agricultural machine (1). Autonomous agricultural machine (1) according to the preceding claim, comprising containment panels arranged on the sides of the autonomous agricultural machine (1) and configured to block the diffusion of active product to the outside of the useful volume (20).

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