METHOD FOR PROCESSING A PLOT OF LAND WITH AT LEAST TWO AGRICULTURAL ROBOTS

Description

[0001] The present invention relates to the field of agricultural machinery and more particularly to the working of the soil or plants of an agricultural plot, and has as its object a method of working a plot automatically and simultaneously by a fleet of at least two agricultural machines or robots, as well as an agricultural unit to carry out this method.

[0002] In agriculture, it is well known that when a fleet of autonomous agricultural machines (robots) is working a plot of land, the distribution of labor within the plot is crucial to ensuring the system's efficiency. Similarly, it is vital to minimize potential collisions between the different machines.

[0003] Typically, a plot P is divided into a main field CP (optimally usable area SU) and a headland area that borders this main field on all or part of its peripheral circumference (see [Fig.1][Fig.1 ] - headland all around the field). Typically, this headland is present at least at each end of the rows or working paths of the plot and is used by machinery to make U-turns and more generally to maneuver from one row to another of the main field.

[0004] As is well known and common practice, autonomous robotic vehicles within the same fleet communicate with each other (via radio frequency, either directly or through a central system) to constantly monitor the positions of other vehicles. Other master-slave solutions (where a slave robot follows and replicates the path of a master robot) also exist.

[0005] However, these known solutions require constant bidirectional exchanges and therefore permanent communication between robots: this results in complex needs in terms of data flow and connections between the machines and the network.

[0006] Alternatively, known master-slave solutions impose a dependency of the slave robot(s) on the master robot(s): the two types of machines cannot truly work independently, but only in pairs or groups, which reduces efficiency. Furthermore, the robot(s) must again be managed via a permanent communication link.

[0007] Finally, other solutions recommend dividing the plot to be worked into working zones of fixed width corresponding to the working width of the agricultural robots being used (each zone is worked in a single pass) and assigning these zones to the different robots. These zones are assigned / reassigned in real time based on the progress of the work being carried out by the various robots and the evolving situation. A solution of this type is disclosed in document EP 3 508 045, US 2018 / 364739 A1 or US 2019 / 0146513.

[0008] In this latter scenario, when a robot wants to move to a new zone (after completing its task in a given zone) by passing through the impound lot, or wants to make a U-turn in the impound lot at the end of a zone, and an obstacle (such as another robot) blocks its path, then this robot, whether in transit or exiting a zone, either waits for the path to clear or searches for an alternative route to reach the objective or perform its maneuver (choosing the shortest alternative). Zones or rows where the adjacent impound lots at the ends are blocked are temporarily off-limits and are not permitted when a robot needs to change zones.

[0009] The result of all these known solutions, and in particular the last one, is a complex management of impoundment in the case of a fleet of several agricultural robots (prioritization, collision avoidance, ...).

[0010] The present invention aims to overcome these drawbacks, and in particular to provide a solution that minimizes collision management and allows for efficient coordination of different robots without requiring communication between them.

[0011] To this end, the invention relates to a method for working a plot of land simultaneously by a fleet of at least two autonomously and independently operating agricultural machines or robots, in accordance with instructions and / or commands transmitted by a common central management and control system, said method consisting of subdividing said plot to be worked, prior to the start of work on this plot or progressively during the work thereof, into at least two distinct work zones, the whole of said work zones covering substantially the entire usable or useful surface area of ​​said plot, each work zone consisting of a strip-shaped portion of the plot with respective extremities at its two opposite ends, and a headland zone extending along the various successive adjacent extremities at each of the two opposite ends of said strips,a method characterized in that it consists of subdividing each headland area into headland sections, each of which is located opposite and in continuity with one of the two ends of one of the strips forming work zones, and of assigning at least a fraction of a headland section, temporarily and exclusively, to the robot that is either about to or crossing the headland section in question, or is about to begin, is carrying out, or is about to complete the work of the work zone associated with said headland section in question, the actions and / or movements of at least some of the other robots being possibly influenced by this exclusive temporary assignment, through said central management and control system.

[0012] The invention will be better understood from the following description, which relates to preferred embodiments, given by way of non-limiting examples, and explained with reference to the accompanying schematic drawings, in which: [ Fig.2 ] represents, for a rectangular plot, a partial division of the field into working zones with a headland zone around the entire perimeter and subdivided into portions; [ Fig.3 ] represents the plot of the [ Fig.2 ] after allocation with alternating uniform work zones according to the same pattern or repetitive scheme of the type ABC, ABC, ... ; [ Fig.4 ] represents the plot of figures 2 And 3 after subdivision of the total field with alternating allocation of uniform work zones according to a different repeating pattern or scheme similar to that of the [ Fig.3 ] and with a (terminal) band of a different size (narrower); ] Fig.5 ] represents a plot with total field subdivision and alternating allocation of uniform work zones according to the same pattern or repetitive scheme as that of the [ Fig.4 ] (type ABC, ABC,...), without side headlands (only headlands at the opposite ends of the rows) and with a (terminal) strip of a different size; [ Fig.6 ] represents the plot of the [ Fig.2 ] on which the main constituent components of an example of an agricultural assembly for carrying out the process according to the invention (central management and control system - autonomous robotic agricultural work machines) are represented, and, [ Fig.7 ] illustrates a plot of land whose main field is treated by four different robots and shows a possible conflict / collision situation between them, managed in accordance with the invention (exclusive allocation of pound portions).

[0013] As shown by figures 2 à 6 The invention relates to a method of working a plot (P) simultaneously by a fleet of at least two agricultural machines or robots (R1, R2, ..., Ri) operating autonomously and independently, in accordance with instructions and / or commands transmitted by a common central management and control system (SC).

[0014] This process consists of subdividing said plot (P) to be worked, prior to the start of the work of this plot (P) or progressively during the work thereof, into at least two distinct working zones (Z1, Z2, ..., Zj), the whole of said working zones (Z1, Z2, ..., Zj) covering substantially the entire usable or useful surface (SU) of said plot (P) - also called main field CP -, each working zone (Z1, Z2, ..., Zj) consisting of a fraction of plot in the form of a strip with at its two opposite ends respective extremities (EB, EB'), and a headland zone (F, F') extending along the different successive neighboring extremities (EB or EB') at each of the two opposite ends of said strips (Z1, Z2, ..., Zj).

[0015] This method is characterized in that it further consists of subdividing each headland zone (F, F') into headland portions (PF1, PF1'; PF2, PF2';...; PFj, PFj'), each of which is located opposite and in continuity with one of the two ends (EB and EB') of one of the strips forming work zones (Z1, Z2, ..., Zj), and of assigning at least a fraction of a headland portion (PF1, PF1'; PF2, PF2';...; PFj, PFj'), temporarily and exclusively, to the robot (R1, R2, ..., Ri) which is either about to or crossing the headland portion (PF1, PF1'; PF2, PF2';...; PFj, PFj') considered, or is about to begin, is performing, or is about to complete work in the work zone (Z1, Z2, ..., Zj) associated with said impoundment portion (PF1, PF1'; PF2, PF2' ;...; PFj, PFj') considered, the actions and / or movements of at least some of the other robots being possibly influenced by this exclusive temporary assignment, through said central management and control system.

[0016] Of course, the method according to the invention can also be applied to the parts or zones of lateral headlands FL, FL' that may extend on either side of the main field CP, according to the direction of the rows, when such parts of headlands are present. Each part of lateral headland FL, FL' is then treated as a portion of headland PF.

[0017] Thus, by allocating exclusive access to specific sections of the field to certain agricultural robots for predetermined periods through the central management and control system, the invention significantly facilitates the management of a fleet of robots operating simultaneously on the same plot, and more specifically, the handling of potential collisions by limiting robot crossings. Furthermore, these robots do not need to know the positions of other robots and, above all, require no communication with each other.

[0018] In general, and within the scope of the invention, a portion of a pound (or at least a fraction thereof) is temporarily made exclusive to a given robot when the latter requires it, at least for the duration that the robot resides there. This exclusive allocation, with access prohibited to other robots, is preferably at least slightly anticipated (before the robot actually enters the portion reserved exclusively for it) and can result from the application of various rules depending on the user's choice (prioritization, chronological order, depending on the type of robot, etc.).

[0019] In accordance with a first simple implementation variant, the method may consist of temporarily and exclusively assigning a given portion or fraction of a portion of the impoundment (PF1, PF1'; PF2, PF2'; ...; PFj, PFj') to the robot (R1, R2, ..., Ri) that enters, or is about to enter, first into said portion or fraction of the impoundment considered

[0020] In accordance with a second implementation variant, it may be possible to temporarily and exclusively allocate a given portion or fraction of a portion of the headland (PF1, PF1'; PF2, PF2'; ...; PFj, PFj') to a specific robot (R1, R2, ..., Ri) based on a predetermined logical prioritization rule applied by the central common management and control (SC) system. Thus, in the case of agricultural robots of different sizes, priority may be given to the larger robots.

[0021] Of course, the two headland sections PF and PF' located at the two opposite ends EB and EB' of the same work zone Z can be assigned momentarily and exclusively to two different robots (the one assigned to the work zone Z making, for example, a U-turn in a first section, and the other robot - in transit between two zones - crossing the other section).

[0022] According to one feature of the invention, the method consists, after exclusive allocation of a portion of the pound (PF1, PF1'; PF2, PF2'; ...; PFj, PFj') to a specific robot (R1, R2, ..., Ri), by applying a pre-programmed allocation rule at the level of the central common management and control system (SC), of coordinating and controlling accordingly, as needed, the operation and movement of the other robots active on the plot (P), by means of said system (SC). This control of the other robots may, for example, consist of updating the movement zones temporarily prohibited to those other robots likely to pass through the exclusively allocated portion.

[0023] The width of the headland (F, F') depends on the width of the associated working area, its depth (dimension in the longitudinal direction of the associated working strip), as well as the width of the lateral headland parts (FL, FL') which can be variable.

[0024] In particular, when the PF headland sections are quite deep, the exclusive temporary allocation of a headland section (PF1, PF1'; PF2, PF2'; ...; PFj, PFj') to a specific robot (R1, R2, ..., Ri) may only concern a fractional strip (BF) of the headland section in question, which is directly adjacent to the end of the relevant work zone (EB, EB'). In other words, the fractional strip complementary to BF (which completes BF to form PFj) may remain free of movement and access (the reverse may also apply - BF free). According to another variant, arising from the [ Fig.7 ], the exclusive temporary allocation of a portion of the pound (PF1, PF1'; PF2, PF2' ;... ; PFj, PFj') to a fractional region (RF) of this portion, located within the latter, and which can for example serve as a waiting area, parking area, refueling area, maintenance area, etc ..., for a given robot (R1).

[0025] In accordance with a feature of the invention, the exclusive temporary assignments of the headland portions (PF1, PF1'; PF2, PF2' ;... ; PFj, PFj') to the different robots (R1, R2, ..., Ri) are advantageously carried out progressively, as the work progresses in the work zones (Z1, Z2, ..., Zj) of the plot (P) considered by the robots.

[0026] Thus, depending on the option chosen, these working zones (Z1, Z2, ..., Zj) can either all be established before work begins on the relevant plot (P) (pre-division of the plot), or be defined gradually as work progresses in the plot (P). They may (or may not) all have the same width Lz (particularly when the robots are identical), except possibly for a narrower terminal or finishing strip BT.

[0027] When the plot (P) has a surrounding peripheral headland, which includes the two terminal headland areas (F, F') along the ends (EB, EB') of the working areas (Z1, Z2, ..., Zj) as well as two lateral headland areas (FL, FL') connecting the two aforementioned extreme headland areas, it may be provided for temporarily and exclusively allocating part or all of each of these two lateral headland areas (FL, FL') to the robot (R1, R2, ..., Ri) which enters the lateral headland area in question first.

[0028] According to an advantageous feature of the invention, it is possible to temporarily assign or allocate each work zone (Z1, Z2, Zj) exclusively to one of the agricultural robots (R1, R2, Ri), at least during the work phase in question (to be performed by that robot). The width (Lz) of the majority of the work zones (Z1, Z2, Zj) is advantageously greater than or equal to the working width (Lr) of the agricultural robot (R1, R2, Ri) exclusively assigned to it, preferably equal to an integer multiple thereof.

[0029] In addition, the exclusive allocation, during the work of the plot (P), of the work zones (Z1, Z2, Zj) still to be worked, to the different agricultural robots (R1, R2, Ri), is carried out progressively, according to the completion of the work in progress in the different work zones by the agricultural robots which have been respectively assigned to them.

[0030] Furthermore, after an initial allocation of a first exclusive work zone to each agricultural robot, the subsequent allocations, at a given time during the execution of the work of the plot (P), of the future work zones, forming the part remaining to be worked (PRP) of said plot (P), to the different agricultural robots can be carried out progressively according to the completion of the work in progress in the different work zones by the agricultural robots which have been respectively allocated to them.

[0031] Advantageously, all work zones (Z1, Z2, Zj) are assigned to the different agricultural robots (R1, R2, Ri), with an exclusive assignment of one robot per zone, before the work of the plot (P) or at the beginning thereof, a possible reassignment of the remaining work zones to be worked, between the different agricultural robots considered, can take place at a determined time during the execution of the work of the plot (P), depending on the evolution of the behavior, the availability and / or the condition of the different robots, or the actual or foreseeable progress of the work in the work zones still subject at the aforementioned time to the work by the respective robots which have been exclusively assigned to them.

[0032] Advantageously, the subdivision of the plot (P) and the allocation of exclusive working areas (Z1, Z2, Zj) to the different agricultural robots (R1, R2, Ri) takes into account a minimization of the crossings of said robots at the level of the headland(s) (F) during changes of working areas, the exclusive allocation of a given working area (Z1, Z2, Zj) to a specific robot (R1, R2, Ri) resulting in either an exclusive temporary allocation, or at least a priority reservation, for said specific robot, of the headland portion(s) extending opposite and in continuity with one of the two ends (EB and EB') of the strip-shaped working area (Z1, Z2, ..., Zj).

[0033] Similar to exclusive work zones, adjacent sections of impoundment may not be directly adjoining.

[0034] The definition, exclusive allocation and management of work in such work areas can, for example, be carried out in accordance with the process described in French patent application no. FR2009696 filed today in the name of the applicant.

[0035] An example of a relatively complex situation involving the management of a possible collision / conflict is illustrated on the [ Fig.7 In this example, both R1 and R2 are in a situation of future transfer movement. R1 wants to leave its parking zone (RF) to reach an assigned work zone (Z1), and R2 wants to leave the work zone (Z2) it has just finished to reach a parking zone (RF) located in the impoundment section (PF3) extending from the work zone (Z3) being worked by robot (R3). The work zone (Z4) is being worked by robot (R4), and robots (R3) and (R4) are about to turn around in the impoundment sections (PF3 and PF4). In this context and configuration, it can be decided that the first robot to move has priority. The figure shows that the robot (R1) was the first to move and all the sections of the headlands (PF1, PF2 and PF4) that it must cross to reach (Z1) are temporarily and exclusively reserved for it.Initially, (R2) and (R4) are waiting in their respective work zones. However, R3 can turn around because the headland section (PF3) must not be traversed by (R1). Since (PF4) is temporarily reserved for the passage of (R1), (R4) must wait for (R1) to pass before turning around. However, it should be able to do so before (R2) reaches (RF) in (PF3), because (PF4) will be freed up before (PF2) following the passage of (R1), unless a logic other than time prioritization is applied in this case (for example: importance or size of the robot, type of task to be performed, etc.).

[0036] The invention also aims, as shown by the [ Fig.6], an agricultural unit for the automated working of plots (P) comprising a fleet of at least two mobile agricultural machines or robots (R1, R2, ..., Ri), equipped with suitable working tools, operating autonomously and independently, and a common central management and control system (SC) capable of communicating with said robots in order to transmit instructions and / or commands to them and to receive in return information on the operation and / or status of said robots.

[0037] Each robot is equipped with a satellite positioning or localization device and said central management and control system (SC) includes means to subdivide said plot (P) to be worked, prior to the start of work on this plot (P) and / or progressively during the work on it, into at least two distinct work zones (Z1, Z2, ..., Zj).

[0038] The work zones collectively cover approximately the entire surface area of ​​the plot. Each work zone (Z1, Z2, ..., Zj) consists of a strip-shaped portion of the plot with two opposite ends (EB, EB'), and a headland zone (F, F') extends along the successive adjacent ends (EB or EB') at each of the two opposite ends of said strips (Z1, Z2, ..., Zj). Where applicable, lateral headland zones (FL, FL') may also be present.

[0039] According to the invention, the central common management and control system (SC) comprises means (processing unit and calculation and control programs) for subdividing each headland zone (F, F') into headland sections (PF1, PF1'; PF2, PF2'; ...; PFj, PFj'), each of which is located opposite and in continuity with one of the two ends (EB and EB') of one of the strips forming work zones (Z1, Z2, ..., Zj), and for assigning at least a fraction of a headland section (PF1, PF1'; PF2, PF2'; ...; PFj, PFj'), temporarily and exclusively, to the robot (R1, R2, ..., Ri) that is either about to or in the process of crossing the headland section (PF1, PF1'; PF2, PF2'; ...; PFj, PFj') under consideration, or is about to begin, is in the process of to carry out or will complete the work of the work zone (Z1, Z2, ..., Zj) associated with said portion of pound (PF1, PF1'; PF2, PF2' ;... ; PFj, PFj') considered.

[0040] Preferably, this set implements the process described above to ensure the management of the fleet of robots (R1, R2, Ri) during the work of a plot (P).

[0041] Of course, the invention is not limited to the embodiments described and shown in the accompanying drawings. Modifications remain possible, particularly with regard to the composition of the various elements, as long as the scope of protection of the invention as defined by the independent claims is respected.

Claims

1. Method for working a plot of land (P) simultaneously by a fleet of at least two agricultural machines or robots (R1, R2, ..., Ri) operating autonomously and independently, in accordance with instructions and / or commands transmitted by a common central management and control system (SC), the method consisting in subdividing the plot of land (P) to be worked, prior to starting working on this plot of land (P) or progressively during work thereon, into at least two distinct work areas (Z1, Z2, ..., Zj), the whole work areas (Z1, Z2, ..., Zj) covering substantially the entire exploitable or usable surface area (SU) of the plot of land (P), each work area (Z1, Z2, ..., Zj) consisting of a fraction of plot of land in the form of a strip with respective extremities (EB, EB') at the two opposite ends thereof, and a headland area (F, F') extending along the various successive adjacent extremities (EB or EB') at each of the two opposite ends of the strips (Z1, Z2, ..., Zj), method characterised in that it further consists in subdividing each headland area (F, F') into headland portions (PF1, PF1'; PF2, PF2'; ...; PFj, PFj'), each of which facing and being located in the continuation of one of the two extremities (EB and EB') of one of the strips forming work areas (Z1, Z2, ..., Zj), and assigning at least a fraction of a headland portion (PF1, PF1'; PF2, PF2'; ...; PFj, PFj'), temporarily and exclusively, to the robot (R1, R2; ..., Ri) that either is about to pass or is in the process of passing through the considered headland portion (PF1, PF1'; PF2, PF2'; ...; PFj, PFj'), or is going to start, is in the process of completing or going to complete work in the work area (Z1, Z2, ..., Zj) associated to the considered headland portion (PF1, PF1'; PF2, PF2'; ...; PFj, PFj'), the actions and / or displacements of at least some of the other robots possibly being influenced by this temporary exclusive assignment, via the central management and control system.

2. Method according to claim 1, characterised in that it consists in assigning temporarily and exclusively a given headland portion or a fraction of a headland portion (PF1, PF1'; PF2, PF2'; ...; PFj, PFj') to a specific robot (R1, R2, ..., Ri) according to a predetermined prioritisation logic rule, applied by the common central management and control system (SC).

3. Method according to any one of claims 1 or 2, characterised in that it consists, after exclusive assignment of a given headland portion (PF1, PF1'; PF2, PF2'; ...; PFj, PFj') to a specific robot (R1, R2, ..., Ri), by application of a preprogrammed assignment rule in the common central management and control system (SC), in coordinating and controlling accordingly, as far as required, the operation and displacement of the other robots working on the plot of land (P), via the system (SC).

4. Method according to any one of claims 1 to 3, characterised in that the temporary exclusive assignment of a headland portion (PF1, PF1'; PF2, PF2'; ...; PFj, PFj') to a specific given robot (R1, R2, ..., Ri), only concerns a fractional strip (BF) of the considered headland portion, which is directly adjacent to the extremity of the considered work area (EB, EB').

5. Method according to any one of claims 1 to 4, characterised in that the temporary exclusive assignments of the headland portions (PF1, PF1'; PF2, PF2'; ...; PFj, PFj') to the various robots (R1, R2, ..., Ri) are performed progressively, as the work carried out by the robots proceeds in the work areas (Z1, Z2, ..., Zj) of the considered plot of land (P).

6. Method according to any one of claims 1 to 5, characterised in that it consists in assigning temporarily each work area (Z1, Z2, Zj) exclusively to one of the agricultural robots (R1, R2, Ri), at least during the considered work phase, the width (Lz) of most of the work areas (Z1, Z2, Zj) being advantageously greater than or equal to the working width (Lr) of the agricultural robot (R1, R2, Ri) exclusively assigned to it, preferably equal to an integer multiple of this working width, and in that the exclusive assignment, as work proceeds on the plot of land (P), of the work areas (Z1, Z2, Zj) still to be worked, to the various agricultural robots (R1, R2, Ri), is performed progressively, as the work being carried out in the various work areas is completed by the agricultural robots which have been respectively assigned to them.

7. Method according to claim 6, characterised in that all the work areas (Z1, Z2, Zj) are assigned to the various agricultural robots (R1, R2, Ri), with an exclusive assignment of one robot per area, before or when starting work on the plot of land (P), a possible reassignment of the work areas still to be worked between the various considered agricultural robots being able to take place, at a given time as work proceeds on the plot of land (P), depending on the behavioural change, availability and / or status of the various robots, or even on the actual or predictable progress of the work in the work areas still worked at the above-mentioned time by the respective robots which have been exclusively assigned to them.

8. Method according to any one of claims 1 to 7, characterised in that the subdivision of the plot of land (P) and the assignment of the exclusive work areas (Z1, Z2, Zj) to the various agricultural robots (R1, R2, Ri) take into account a minimisation of the crossing between the robots in the headland(s) (F) when changing work areas, the exclusive assignment of a given work area (Z1, Z2, Zj) to a specific robot (R1, R2, Ri) resulting either in an exclusive temporary assignment, or at least a priority reservation, for the specific robot of the headland portion(s) facing and extending in the continuation of one of the two extremities (EB and EB') of the work area in the form of strips (Z1, Z2, ..., Zj).

9. Agricultural machinery assembly for the automated work of plots of land (P) comprising a fleet of at least two mobile agricultural machines or robots (R1, R2, ..., Ri), equipped with suitable work tools, operating autonomously and independently, and a common central management and control system (SC) adapted to communicate with the robots to transmit them instructions and / or commands and receive in return information concerning the operation and / or status of the robots, each robot further being provided with a satellite positioning or tracking device, the central management and control system (SC) comprising means making it possible to subdivide the plot of land (P) to be worked, prior to starting working on this plot of land (P) and / or progressively as work proceeds thereon, into at least two distinct work areas (Z1, Z2, ..., Zj), the whole of the work areas covering substantially the entire surface of the plot of land, each work area (Z1, Z2, ..., Zj) consisting of a fraction of plot of land in the form of a strip having respective extremities (EB, EB') at the two opposite ends thereof, and a headland area (F, F') extending along the various successive adjacent extremities (EB or EB') at each of the two opposite ends of the strips (Z1, Z2, ..., Zj), assembly characterised in that the common central management and control system (SC) further comprises means making it possible to subdivide each headland area (F, F') into headland portions (PF1, PF1'; PF2, PF2'; PFj, PFj'), each of which facing and being located in the continuation of one of the two extremities (EB and EB') of one of the strips forming work areas (Z1, Z2, ..., Zj), and to assign at least a fraction of a headland portion (PF1, PF1'; PF2, PF2'; PFj, PFj'), temporarily and exclusively, to the robot (R1, R2; ..., Ri) that either is about to pass or is in the process of passing through the considered headland portion (PF1, PF1'; PF2, PF2'; ...; PFj, PFj'), or is going to start, is in the process of completing or going to complete work in the work area (Z1, Z2, ..., Zj) associated with the considered headland portion (PF1, PF1'; PF2, PF2'; ...; PFj, PFj'),10. Assembly according to claim 9, characterised in that it implements the method according to any one of claims 1 to 8 to manage the fleet of robots (R1, R2, Ri) when working a plot of land (P).