Self-propelled agricultural machine whose balance can be controlled and adjusted

Abstract

Agricultural machine (1), of which the assembly connection between the support frame (2) and the running-gear (4) is configured to allow a movement between this support frame (2) and this running-gear (4) along the longitudinal axis (L); the machine also comprises means for determining and optionally adjusting, if necessary, automatically by an evaluation and control means (8) or on command of an operator informed by this means (8), the relative positioning between the support frame (2) and the running-gear (4), such that the centre of gravity (CG) of the support frame (2) with its tool(s) (3, 3') and a central point (C) of the running-gear (4) are mutually close, advantageously located in a same plane (P) perpendicular to the longitudinal axis (L) and preferably coincident.

Description

Description Title of the invention: Self-propelled agricultural machine whose balance can be controlled and adjusted

[0001] The present invention relates to the field of agricultural machinery, more particularly the balancing and safety of agricultural machines capable of being provided with tools of different types and weights, possibly variable, and has as its subject an agricultural machine whose balance can be controlled and adjusted.

[0002] The invention relates in particular to a self-propelled agricultural machine, operating autonomously or controlled by an operator, having a usual direction of advance, which determines the front and the rear and a longitudinal axis for the machine. The type of agricultural machine concerned comprises, on the one hand, a support frame configured to carry at least one tool at the front and / or at the rear and, on the other hand, a rolling assembly. The latter comprises, as rolling means, either at least one tracked rolling train, and possibly at least one additional rolling train with a wheeled axle, or at least two rolling trains with wheeled axles, the support frame being mounted on and assembled with the rolling assembly and carrying at least one tool.

[0003] Thus, depending on the tools carried or attached to the front or rear, their variation in weight and / or position, the center of gravity of the upper part of the machine (support frame + tools), and therefore of the machine as a whole, may be offset to a greater or lesser extent in relation to the ground supports of the machine, resulting in particular instability and reduced performance when moving the machine, possible deformation of parts of it, non-uniform wear of the running gear and a deviation from a setpoint for machines operating independently.

[0004] These disadvantages are particularly penalizing for tracked agricultural machines and lead, for example, to:

[0005] - ground pressure that is too high in some areas, because the load is distributed unevenly

[0006] - a ground contact surface less than the lower surface of the tracks, since the machine leans forward or backward, and the tracks are therefore not not completely in contact with the ground: the traction and stability of the machine are therefore not optimal

[0007] - the need for additional ballast to compensate for poor mass distribution, which results in an unnecessary additional ground load and therefore greater soil compaction, which is of course not desired.

[0008] In addition, some tools have hoppers or tanks (seeders, various fertilizer spreaders, plant protection sprayers, etc.). As work progresses in an agricultural plot, these tanks will empty, then be refilled by the farmer until the end of the work. These changes involve a significant change in mass and therefore a change in the position of the center of gravity.

[0009] Furthermore, a tracked machine whose center of gravity is not the same as its instantaneous center of rotation is more difficult to guide autonomously (via GPS), because a recalibration of the guidance system is necessary each time the position of the center of gravity changes. This recalibration requires a complex algorithm for managing the steering commands of each of the tracks.

[0010] The present invention aims to overcome these drawbacks, and not only for tracked agricultural machines.

[0011] To this end, it relates to an autonomous agricultural machine of the type mentioned in the introduction, characterized in that the assembly connection between the support frame and the rolling assembly is configured to allow movement between this frame and this assembly along the longitudinal axis, and in that it comprises means for determining and possibly adjusting, if necessary, automatically by an evaluation and control means or on command of an operator informed by this means, the relative positioning between the support frame and the rolling assembly, in such a way that the center of gravity of the support frame with its tool(s) and a central point of the rolling assembly are mutually close, advantageously located in the same plane perpendicular to the longitudinal axis and preferably coincident.

[0012] The invention will be better understood from the following description, which relates to preferred embodiments, given as non-limiting examples, and explained with reference to the appended schematic drawings, in which:

[0013] [Fig. 1] is a functional schematic representation of a self-propelled agricultural machine according to the invention;

[0014] [Fig. 2A] and

[0015] [Fig. 2B] are schematic side elevation views of an agricultural machine according to a first variant of a first embodiment of the invention (tracked undercarriage), respectively in an unbalanced configuration (fig. 2A) and in a balanced configuration (fig. 2B);

[0016] [Fig. 3A] and

[0017] [Fig. 3B] are schematic side elevation views of an agricultural machine according to a second variant of the first embodiment of the invention (tracked undercarriage), in two balanced configurations despite different levels in the front-mounted hopper, thanks to the controlled offset between the support frame and the rolling assembly;

[0018] [Fig. 4A] and

[0019] [Fig. 4B] are schematic side elevation views of an agricultural machine according to a third variant of the first embodiment of the invention (tracked undercarriage), in two balanced configurations despite different levels in the rear-mounted hopper, thanks to the controlled offset between the support frame and the rolling assembly;

[0020] [Fig. 5A] and

[0021] [Fig. 5B] are schematic side elevation views of an agricultural machine according to a fourth variant of the first embodiment of the invention (tracked undercarriage), in two balanced configurations despite different levels in the rear-mounted hopper, thanks to the controlled offset between the support frame and the rolling assembly;

[0022] [Fig. 6A] and

[0023] [Fig. 6B] are schematic side elevation views of an agricultural machine according to a fifth variant of the first embodiment of the invention (tracked undercarriage), in two balanced configurations despite different levels of the fuel tank, thanks to the controlled offset between the support frame and the rolling assembly;

[0024] [Fig. 7A] and

[0025] [Fig. 7B] are schematic side elevation views of an agricultural machine according to a first variant of a second embodiment of the invention (train with wheeled axles), respectively in an unbalanced configuration (fig. 7A) and in a balanced configuration (fig. 7B);

[0026] [Fig. 8A] and

[0027] [Fig. 8B] are schematic side elevation views of an agricultural machine according to a second variant of the second embodiment of the invention (train with wheeled axles), in two balanced configurations despite different levels in the front-mounted hopper, thanks to the controlled offset between the support frame and the rolling assembly;

[0028] [Fig. 9] is a simplified schematic top view of a machine according to Figures 2 to 8, the tools and other equipment carried by the support frame being removed to visualize the assembly connection between the bearing assembly and the support frame, and,

[0029] [Fig. 10A] and

[0030] [Fig. 10B] are views similar to Figure 9, showing the bearing assembly in two extreme positions of offset along the longitudinal axis relative to the support frame, respectively in the maximum front position (10A) and in the maximum rear position (10B).

[0031] Figures 1 to 8 illustrate a self-propelled agricultural machine (1) operating autonomously or controlled by an operator, having a usual direction of advance (A), which determines the front and rear of the machine and a longitudinal axis (L) for this machine (1).

[0032] This agricultural machine (1) comprises, on the one hand, a support frame (2) configured to carry at least one tool (3, 3') at the front and / or at the rear and, on the other hand, a rolling assembly (4) comprising, as rolling means, either at least one rolling train (5) with tracks (5'), and possibly at least one additional rolling train with axle (6, 6') with wheels (6”), or at least two rolling trains with axles (6, 6') with wheels (6”), the support frame (2) being mounted on and assembled with the rolling assembly (4) and carrying at least one tool (3, 3').

[0033] As also shown by way of example in Figures 2 to 8, the tool, at least one of the tools or both front and rear tools (3, 3') may be mounted fixedly or movably on the support frame (2) and have a constant or variable mass. In particular, the tool or one of the tools (3, 3') may comprise a hopper (12) or a similar reservoir, which empties and / or fills during the operation of the machine (1), gradually or episodically. In addition, the support frame (2) may carry at the front or rear a ballast weight (3”), possibly movable, or attached via a weight holder (13”) or the like. The various interchangeable tools and similar equipment of the machine (1) are generally secured to and carried by the support frame (2), by means of coupling devices with front (13) and rear (13') lifting.However, it is of course understood that other equipment necessary and useful for the operation of the machine (1), as well as certain tools, may be mounted above the support frame or even hung with locking in position on the top of the machine, or even hung under the bottom of the latter.

[0034] According to the invention, the agricultural machine (1) is characterized in that the assembly connection between the support frame (2) and the rolling assembly (4) is configured to allow movement between this frame and this assembly along the longitudinal axis (L), and in that it comprises means for determining and possibly adjusting, if necessary, automatically by an evaluation and control means (8) or on command of an operator informed by this means (8), the relative positioning between the support frame (2) and the rolling assembly (4), in such a way that the center of gravity (CG) of the support frame (2) with its tool(s) (3, 3') and a central point (C) of the rolling assembly (4) are mutually close, advantageously located in the same plane (P) perpendicular to the longitudinal axis (L) and preferably coincident.

[0035] Ideally, it is assumed that the machine (1) is balanced transversely with respect to a plane containing the longitudinal axis (L) and perpendicular to the plane (P). However, the balancing according to the invention can also be implemented when such transverse balancing is not verified. In this case, in Figures 2 to 8, the crosses will not represent the aforementioned center of gravity (CG) and central point (C), but horizontal lines enclosing them and perpendicular to the longitudinal axis (L), and the same situation of proximity between them, advantageously of coplanarity and preferably of mutual confusion, will be sought.

[0036] Thus, the invention makes it possible to overcome the aforementioned drawbacks and proposes a simple and integrated solution making it possible i) to achieve an optimized relative positioning between the support frame (2) and the rolling assembly (4), depending on a given configuration of the different masses corresponding to the tools or similar accessories carried by the support frame (2), and ii) to maintain or return to such an optimized positioning when the distribution of the masses either changes due to a change of tools or removable accessories carried, or evolves during a work phase or between two consecutive work phases of the machine (1).

[0037] By achieving and maintaining a centralized positioning of the supporting frame (2) relative to the rolling assembly (4), optimal stability of the machine (1) and maximum contact with the ground (S) are achieved, as well as a load distributed substantially at the level of the support surfaces, resulting in optimized grip and traction. In addition, a significant limitation of the need for ballast makes it possible to reduce the impact on the ground (S). In addition, GPS guidance of the machine (1) is facilitated, the center of gravity and the instantaneous center of rotation always being the same. Furthermore, in the event of a variation in the mass of a tool (for example emptying a hopper), the evolution of this variation can be monitored indirectly by tracking the adjustment of the relative positioning.Finally, it should be noted that the solution of the invention is compatible with all types of tools, accessories, equipment and weights, and suitable for all lifting configurations for tools or hanging ballast weights.

[0038] According to a first embodiment variant, the central point (C) of the rolling assembly (4) corresponds to the geometric center or barycenter of the contact zones between the rolling gears (5, 5'; 6, 6', 6”) and the ground (S).

[0039] According to a second variant embodiment and when the rolling assembly (4) comprises only a running gear (5) with tracks (5'), the central point (C) of the rolling assembly (4) corresponds to the geometric center of the running gear (5) or to the midpoint of a drive axle of this running gear (5).

[0040] According to a third variant embodiment and when the rolling assembly (4) comprises two rolling trains (5, 5'; 6, 6', 6”), the central point (C) corresponds to the midpoint between the geometric centers of the axles of the two rolling trains (5, 5'; 6, 6', 6”).

[0041] As shown schematically in Figures 9 and 10, the assembly connection between the support frame (2) and the rolling assembly (4) has a degree of freedom for sliding along the longitudinal axis (L) and comprises one or more jacks (7), which can be locked in position, the actuation of at least some of which, in particular at least one electric jack provided with a position sensor, causes a relative sliding movement between the frame and the assembly.

[0042] As illustrated in particular in Figures 3 to 5 and 8, the tool (3, 3') or at least one of the tools (3, 3') carried by the support frame (2) may have a variable mass and / or may be moved relative to the support frame (2), in particular during use or when the machine (1) is moving from one configuration or state to another, the agricultural machine (1) comprising means (9) for measuring the mass and means (9') for detecting the relative position relative to the support frame (2) of the tool or each of the tools (3, 3') mounted at the front or at the rear. These means (9, 9'), in the form of sensors or detectors, which make it possible to monitor the evolution of the position and the magnitude of the masses corresponding in particular to the different tools and ballasts, allow dynamic adjustment of the relative positioning of the two components concerned (2 and 4).

[0043] As an alternative non-dynamic variant, we can consider a system without weighing where the masses are known via a catalog of possible tools for the machine concerned or via manual user input on a machine control terminal ("Front tool = X kg, Rear tool = Y kg").

[0044] In accordance with an advantageous embodiment of the invention, schematically illustrated in Figure 1, and allowing a dynamic controlled adjustment of the ideal relative positioning of the two components (2 and 4), the machine (1) comprises an evaluation and control means (8) which is configured i) to analyze the data provided by a means (T) for measuring the balance of the machine (1), for example a pendulum device (measuring the inclination with respect to the horizontal), and / or by a database (10), ii) to determine an optimal relative positioning between the support frame (2) and the rolling assembly (4) and iii) to, if necessary, either carry out an adjustment by controlling a relative movement between the support frame (2) and the rolling assembly (4), or to inform an operator, if a condition of coincidence between the center of gravity (CG) of the support frame (2) and its tool(s) (3,3') and a central point (C) of the rolling assembly (4) is not at least approximately realized. The computer-type means (8) will operate under the control of a specific adapted management and control software.,

[0045] Preferably, the machine (1) comprises an evaluation and control means (8) which is configured and programmed: i) to analyze the data provided, on the one hand, by means (9) for measuring the mass of the tool (3, 3') or tools (3 and 3') mounted at the front or at the rear, on the other hand, by means (9') for detecting the relative position of the tool (3, 3') or tools (3 and 3') mounted at the front or at the rear and movable relative to the support frame (2), for example by raising / lowering, and / or, finally, by a database (10), ii) to determine an optimal relative positioning between the support frame (2) and the rolling assembly (4) and iii) to, if necessary, either carry out an adjustment by controlling a relative movement between the support frame (2) and the rolling assembly (4), or inform an operator, if a condition of coincidence between the center of gravity (CG) of the support frame (2) with its tool(s) (3,3') and a central point (C) of the bearing assembly (4) is not at least approximately realized.,

[0046] According to another favorable characteristic of the invention, the machine (1) also comprises a database (10) providing predefined states of optimal relative positions between the support frame (2) and the rolling assembly (4), depending on the type of tool(s) (3, 3') or ballast mass(es) (3”) mounted at the front and / or at the rear, and means (11) for detecting the type of tool(s) (3, 3') or ballast mass(es) (3”) mounted.

[0047] In connection with the provisions mentioned above, the evaluation and control means (8) can be favorably programmed to analyze the data provided by the means (11) for detecting the type of tool(s) (3, 3') or ballast mass(es) (3”) mounted and to consult the database (10), at least at the start of a work or movement phase of the agricultural machine (1), and to possibly (if necessary) proceed to the adjustment of the relative positioning between the support frame (2) and the rolling assembly (4) and / or inform an operator. It is thus possible to define at the start of a given phase a balanced initial configuration of the machine (1).

[0048] Also in connection with the above-mentioned provisions, the evaluation and control means (8) can be favorably programmed i) to repeatedly analyze, if necessary in a quasi-continuous manner, the data provided either by a means (T) for measuring the balance of the machine (1), or by means (9) for measuring the mass and means (9') for detecting the relative position of the tool (3, 3') or tools (3 and 3') mounted at the front or at the rear, and ii) to automatically carry out a repeated determination and adjustment, if necessary in real time and continuously, of the relative positioning between the support frame (2) and the rolling assembly (4), throughout and during a working phase of the agricultural machine (1). Thus, in the case of a tool of variable mass (for example incorporating a hopper which empties during the operation of the machine), a balanced configuration can be permanently guaranteed (see figures 3 to 5 and 8).

[0049] In fully autonomous operation of the machine (1), for example of the agricultural robot type, the dynamic adjustment is done without user intervention as the work progresses in the agricultural plot and according to the needs of the machine. It can also be provided that the machine sends a warning signal to the user (via the machine control interface) to indicate an imbalance or poor distribution of masses. An optimized adjustment of the position of the tracks (5') can then be suggested to the operator to resolve the problem.

[0050] In relation to another advantageous characteristic of the invention, and as shown by way of example in Figures 6, the evaluation and control means (8) can furthermore be programmed to also take into account the filling level of the fuel tank (12') of the agricultural machine (1), and its evolution during the working phase, for the determination and, where appropriate, the adjustment, of an optimal relative positioning between the support frame (2) and the rolling assembly (4).

[0051] The invention also relates, to overcome the drawbacks of the state of the art, to a method for managing the configuration of an agricultural machine (1) of the type mentioned in the introduction to the present document, and in particular of an agricultural machine (1) having the technical provisions and characteristics mentioned above.

[0052] According to the invention, this method consists in providing an assembly connection between the support frame (2) and the rolling assembly (4) which is configured to allow movement between this frame and this assembly along the longitudinal axis (L), and consists in determining and possibly adjusting, if necessary, automatically by an evaluation and control means (8) or on command of an operator informed by this means (8), the relative positioning between the support frame (2) and the rolling assembly (4), in such a way that the center of gravity (CG) of the support frame (2) with its tool(s) (3, 3') and a central point (C) of the rolling assembly (4) are mutually close, advantageously located in the same plane (P) perpendicular to the longitudinal axis (L) and preferably coincident.

[0053] The change of position of the train (5) of tracks (5') is ideally done only in the two cases below:

[0054] -Initial setting before starting work: machine (1) static and tools (3, 3') attached (with hoppers filled to the necessary level if necessary)

[0055] -Dynamic adjustment: in a straight line only to reduce the risk of stability problems of the machine (1) equipped and loaded, which could occur if the dynamic shift were to occur during a turn, a U-turn or a maneuver.

[0056] It may also be provided that the machine (1) adopts one of several predefined configurations (each corresponding to a predetermined relative positioning between the frame and the bearing assembly), namely:

[0057] - a “transport” configuration: for minimal bulk or optimal stability (if tools are hung / attached)

[0058] - a “work” configuration with application of the rule: if a combination of X + Y tools is attached to the machine, then the rolling assembly comes into position Z. A “catalog” of known tools can be integrated into the management software controlling the agricultural machine.

[0059] Of course, the invention is not limited to the embodiments described and shown in the attached drawings. Modifications remain possible, particularly from the point of view of the constitution of the various elements or by substitution of technical equivalents, without departing from the scope of protection of the invention.

Claims

Claims

1. Self-propelled agricultural machine (1) with autonomous operation or controlled by an operator, having a usual direction of advance (A), which determines the front and the rear and a longitudinal axis (L) for the machine (1), this agricultural machine (1) comprising, on the one hand, a support frame (2) configured to carry at least one tool (3, 3') at the front and / or at the rear and, on the other hand, a rolling assembly (4) comprising, as rolling means, either at least one running gear (5) with tracks (5'), and possibly at least one additional running gear with axle (6, 6') with wheels (6”), or at least two running gears with axles (6, 6') with wheels (6”), the support frame (2) being mounted on and assembled with the rolling assembly (4) and carrying at least one tool (3, 3'),agricultural machine (1) characterized in that the assembly connection between the support frame (2) and the rolling assembly (4) is configured to allow movement between this frame and this assembly along the longitudinal axis (L), and in that it comprises means for determining and possibly adjusting, if necessary, automatically by an evaluation and control means (8) or on command of an operator informed by this means (8), the relative positioning between the support frame (2) and the rolling assembly (4), in such a way that the center of gravity (CG) of the support frame (2) with its tool(s) (3, 3') and a central point (C) of the rolling assembly (4) are mutually close, advantageously located in the same plane (P) perpendicular to the longitudinal axis (L) and preferably coincident.

2. Agricultural machine (1) according to claim 1, characterized in that the central point (C) of the rolling assembly (4) corresponds to the geometric center or barycenter of the contact zones between the rolling gears (5, 5'; 6, 6', 6”) and the ground (S).

3. Agricultural machine (1) according to claim 1, characterized in that the rolling assembly (4) comprises only a running gear (5) with tracks (5'), the central point (C) of the rolling assembly (4) corresponding to the geometric center of the running gear (5) or to the midpoint of a drive axle of this running gear (5).

4. Agricultural machine (1) according to claim 1, characterized in that the rolling assembly (4) comprises two rolling trains (5; 6, 6'), the central point (C) corresponding to the midpoint between the geometric centers of the axles of the two rolling trains (5; 6, 6'). [Claim s] Agricultural machine (1) according to any one of claims 1 to 4, characterized in that the assembly connection between the support frame (2) and the rolling assembly (4) has a degree of freedom for sliding along the longitudinal axis (L) and comprises one or more jacks (7), which can be locked in position, the actuation of at least some of which, in particular at least one electric jack provided with a position sensor, causes a relative movement between the support frame (2) and the rolling assembly (4). [Claim s] Agricultural machine (1) according to any one of claims 1 to 5, characterized in that the tool (3, 3') or at least one of the tools (3, 3') carried by the support frame (2) has a variable mass and / or can be moved relative to the support frame (2), in particular during use or when the machine (1) is moving from one configuration or state to another, the agricultural machine (1) comprising means (9) for measuring the mass and means (9') for detecting the relative position relative to the support frame (2) of the tool or of each of the tools (3, 3') mounted at the front or at the rear.

7. Agricultural machine (1) according to any one of claims 1 to 6, characterized in that it comprises an evaluation and control means (8) which is configured i) to analyze the data provided by a means (T) for measuring the balance of the machine (1), for example a balance device, and / or by a database (10), ii) to determine an optimal relative positioning between the support frame (2) and the rolling assembly (4) and iii) to, if necessary, either carry out an adjustment by controlling a relative movement between the support frame (2) and the rolling assembly (4), or to inform an operator, if a condition of coincidence between the center of gravity (CG) of the support frame (2) with its tool(s) (3, 3') and a central point (C) of the rolling assembly (4) is not at least approximately realized. [Claim s] Agricultural machine (1) according to any one of claims 1 to 6, characterized in that it comprises an evaluation and control means (8) which is configured and programmed: i) to analyze the data provided, on the one hand, by means (9) for measuring the mass of the tool (3, 3') or tools (3 and 3') mounted at the front or at the rear, on the other hand, means (9') for detecting the relative position of the tool (3, 3') or tools (3 and 3') mounted at the front or at the rear and movable relative to the support frame (2), for example by raising / lowering, and / or, finally, by a database (10), ii) to determine an optimal relative positioning between the support frame (2) and the rolling assembly (4) and iii) to, if necessary, either carry out an adjustment by controlling a relative movement between the support frame (2) and the rolling assembly (4), or inform an operator,if a condition of coincidence between the center of gravity (CG) of the support frame (2) with its tool(s) (3, 3') and a central point (C) of the bearing assembly (4) is not at least approximately achieved.,

9. Agricultural machine (1) according to any one of claims 1 to 8, characterized in that it comprises a database (10) providing predefined states of optimal relative positioning between the support frame (2) and the rolling assembly (4), depending on the type of tool(s) (3, 3') or ballast mass(es) (3”) mounted at the front and / or at the rear, and means (11) for detecting the type of tool(s) (3, 3') or ballast mass(es) (3”) mounted.

10. Agricultural machine (1) according to claims 8 and 9, characterized in that the evaluation and control means (8) is programmed to analyze the data provided by the means (11) for detecting the type of tool(s) (3, 3') or ballast mass(es) (3”) mounted and to consult the database (10), at least at the start of a work or movement phase of the agricultural machine (1), and to possibly proceed with the adjustment of the relative positioning between the support frame (2) and the rolling assembly (4) and / or inform an operator.

11. Agricultural machine (1) according to any one of claims 7, 8 and 9, characterized in that the means (8) for evaluating and control is programmed to repeatedly analyze, if necessary in a quasi-continuous manner, the data provided by a means (T) for measuring the balance of the machine (1) or by means (9) for measuring the mass and means (9') for detecting the relative position of the tool (3, 3') or tools (3 and 3') mounted at the front or at the rear, and to automatically carry out a determination and a repeated adjustment, if necessary in real time and continuously, of the relative positioning between the support frame (2) and the rolling assembly (4), this throughout and during a working phase of the agricultural machine (1).

12. Agricultural machine (1) according to any one of claims 1 to 11, characterized in that the evaluation and control means (8) is programmed to also take into account the filling level of the fuel tank (12') of the agricultural machine (1), and its evolution during the working phase, for the determination and, where appropriate, the adjustment, of an optimal relative positioning between the support frame (2) and the rolling assembly (4).

13. Method for managing the configuration of an agricultural machine (1), in particular an agricultural machine (1) according to any one of claims 1 to 12, comprising, on the one hand, a support frame (2) configured to carry at least one tool (3, 3') at the front and / or at the rear and, on the other hand, a rolling assembly (4) comprising, as rolling means, either at least one running gear (5) with tracks (5'), and possibly at least one additional running gear with axle (6, 6') with wheels (6”), or at least two running gears with axles (6, 6') with wheels (6”), the support frame (2) being mounted on and assembled with the rolling assembly (4) and carrying at least one tool (3, 3'), method characterized in that it consists in providing an assembly connection between the support frame (2) and the rolling assembly (4) which is configured to allow movement between this frame and this assembly along the longitudinal axis (L),and in that it consists of determining and possibly adjusting, if necessary, automatically by an evaluation and control means (8) or on command of an operator informed by this means (8), the relative positioning between the support frame (2) and the rolling assembly (4), in such a way that, the center of gravity (CG) of the support frame (2) with its tool(s) (3, 3') and a central point (C) of the rolling assembly (4) are mutually close, advantageously located in the same plane (P) perpendicular to the longitudinal axis (L) and preferably merged.

Images