Self-piloted "puncture-proof" load handling machine
The load handling device uses sensors and a control unit to adjust the tool's position relative to the wheels, preventing punctures by maintaining a safe distance, ensuring continuous and safe operation.
Patent Information
- Authority / Receiving Office
- FR · FR
- Patent Type
- Utility models
- Current Assignee / Owner
- Filing Date
- 2024-10-01
- Publication Date
- 2026-04-03
AI Technical Summary
Existing load handling machines with pivoting arms and tools risk puncturing wheels due to operator error, necessitating a safety mechanism to prevent such damage while allowing smooth operation.
A load handling device equipped with sensors and a control unit that automatically adjusts the position of the tool relative to the wheels using actuators to maintain a safe distance, ensuring the tool remains at a predetermined value away from the wheels, even when operated by a human driver.
Prevents wheel punctures by automatically controlling the tool's position, maintaining safety without disrupting the operator's commands, thus ensuring continuous and safe operation.
Smart Images
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Abstract
Description
Title of the invention: Self-piloted "puncture-proof" load handling device
[0001] The present invention relates to the field of load handling.
[0002] In particular, the invention relates to a load handling device and a method for controlling such a load handling device.
[0003] When handling a load with a machine comprising a pivoting arm and a movable tool mounted at the free end of the arm, the tool may, due to operator error, come close to the wheels of the machine. If the approach is too close, a puncture of one of the wheels may occur.
[0004] One object of the invention is to have a device that ensures the safety of the device, while allowing the operator smooth operation.
[0005] To this end, the invention relates to a load handling device comprising a chassis, drive wheels moving on the ground of the chassis, an arm carried by said chassis extending along a longitudinal axis and mounted by means of a first movable pivoting actuator between a low position and a high position, a tool disposed at a free end of the arm, this tool being mounted by means of a second movable pivoting actuator about an axis orthogonal to the longitudinal axis of the arm between a position close to the wheels and a position far from the wheels, a first sensor for determining the angular position of the arm between the high and low positions, a second sensor for determining the angular position of the tool between the positions close to and far from the wheels, a drive element for moving the arm and the tool,the drive unit being operable by the machine operator or being a programmable logic controller, a control unit configured to control the first and second actuators according to the data provided by said drive unit and the first and second sensors, characterized in that the control unit is configured to automatically control the stopping of the first actuator and / or the second actuator or to automatically control the actuation of the first actuator and / or the second actuator to move the tool in the direction of a wheel spacing according to at least the data provided by the first and second sensors to allow the tool to be maintained at a distance from the wheels greater than a predetermined value.
[0006] Thanks to the control unit, which allows automatic stopping of the first actuator and / or the second actuator, or automatic control of the actuation of the first actuator and / or the second actuator to drive the tool in motion in the direction of wheel spacing, based at least on the data provided by the first and second sensors, the invention makes it possible to automatically avoid damage to the wheels of the machine.
[0007] Moreover, when the drive unit is operable by the driver of the machine, from the point of view of the operator who handles the machine, the fact that the control unit acts on the first actuator and / or the second actuator to keep the tool at a distance from the wheels greater than a predetermined value is not very disruptive.
[0008] Furthermore, when the drive element is operable by the driver of the machine, the drive element may be a joystick, a housing on the machine or removable including operating elements, a remote control including operating elements.
[0009] According to one embodiment, only the second actuator can be automatically controlled to maintain the tool at a distance from the wheels greater than a predetermined value. In other words, the movement commands issued by the operator or the autonomous system to the first actuator may not be modified by the control unit. Thus, a load handling operation can be continued by the operator even when the control unit automatically commands the stopping or activation of the second actuator.
[0010] According to one embodiment of the invention, the control unit is configured to, in the actuation state of the drive member, automatically control the stopping of the first actuator and / or the second actuator or automatically control the actuation of the first actuator and / or the second actuator to drive the tool in movement in the direction of a wheel spacing, when the values of the first and second sensors correspond to a pair of predetermined stored values, this pair of predetermined values corresponding to a distance between the tool and the wheels equal to a predetermined value.
[0011] According to one embodiment of the invention, the control unit is configured to, in the actuation state of the drive member, automatically control the stopping of the first actuator and / or the second actuator or automatically control the actuation of the first actuator and / or the second actuator to drive the tool in movement in the direction of a wheel spacing only when the position of the arm is between the lower position and an intermediate position of the arm between the lower and upper positions.
[0012] According to one embodiment of the invention, the control unit is configured to, in the actuated state of the drive element, automatically control the stopping of the first actuator and / or the second actuator or automatically control the actuating of the first actuator and / or the second actuator to drive moving the tool in the direction of a wheel spacing only when the tool's position is between the close wheel position and an intermediate tool position between the close wheel position and the wide wheel position.
[0013] According to one embodiment of the invention, the arm is an adjustable length arm, the device includes a third actuator for adjusting the length of the arm between a minimum length and a maximum length, the device includes a third sensor for determining the length of the arm, and the control unit is configured to automatically control the stopping of the first actuator and / or the second actuator or to automatically control the actuation of the first actuator and / or the second actuator to drive the tool in the direction of a wheel spacing according to at least the data provided by the first, second and third sensors to allow the tool to be maintained at a distance from the wheels greater than a predetermined value.
[0014] According to one embodiment of the invention, the control unit is configured to, in the actuation state of the drive member, automatically control the stopping of the first actuator and / or the second actuator or automatically control the actuation of the first actuator and / or the second actuator to drive the tool in movement in the direction of a wheel spacing only when the length of the arm is between the minimum length and an intermediate length of the arm between the minimum length of the arm and the maximum length.
[0015] The control unit can be configured to automatically control the stopping of the first actuator and / or the second actuator and / or the third actuator or to automatically control the actuation of the first actuator and / or the second actuator and / or the third actuator to drive the tool in the direction of a wheel spacing based on at least the data provided by the first, second and third sensors to allow the tool to be kept at a distance from the wheels greater than a predetermined value.
[0016] Preferably, the movement commands given by the operator on the first actuator and / or the third actuator are unchanged by the control unit, i.e. they are not modified, when the control unit automatically commands the second actuator to stop or automatically commands the second actuator to move the tool in the direction of a wheel spacing.
[0017] According to one embodiment of the invention, the second actuator is a cylinder and the control unit is configured to, in the actuated state of the drive element, automatically control, based at least on the data provided by the first and second sensors, the stop in operation in the direction of a retraction or extension of the cylinder of the second actuator and / or the reversal of the movement of the cylinder of the second actuator.
[0018] According to one embodiment of the invention, the control unit is configured to automatically control the stopping of the first actuator and / or the second actuator or to automatically control the actuation of the first actuator and / or the second actuator to drive the tool in the direction of a wheel spacing based at least on the data provided by the first and second sensors, to allow the maintenance of a first predetermined safety perimeter around the tool at a distance from a second predetermined safety perimeter around the wheels greater than a predetermined value.
[0019] According to one embodiment of the invention, the tool is enclosed within the predetermined safety perimeter around the tool, the tool being at a distance from the predetermined safety perimeter around the tool, and the wheels are enclosed within the predetermined safety perimeter around the wheels, the wheels being at a distance from the predetermined safety perimeter around the wheels.
[0020] According to one embodiment of the invention, the predetermined value to be maintained between the predetermined safety perimeter around the tool and the predetermined safety perimeter around the wheels is between 0 mm and 500 mm.
[0021] The second sensor for determining the angular position of the tool may include a first inclinometer on the tool or the tool support and a second inclinometer on the chassis, the angular position of the tool being determined by the difference between the inclinations measured by the first inclinometer and the second inclinometer.
[0022] According to one embodiment of the invention, the control unit is further configured to automatically control the stopping of the first actuator and / or the second actuator or to automatically control the actuation of the first actuator and / or the second actuator to drive the tool in motion to avoid any risk of tipping of the machine or of a load on the tool.
[0023] According to one embodiment of the invention, the control unit is configured to transmit an alert, in particular an auditory, visual or haptic alert, when it automatically commands the stopping of the first actuator and / or the second actuator or automatically commands the actuation of the first actuator and / or the second actuator.
[0024] The invention further relates to a method for controlling a load handling device, characterized in that, the load handling device conforming to what is described above, the method comprises the automatic stopping of the first actuator and / or the second actuator or the automatic actuation of the first actuator and / or second actuator to drive the tool in movement in the direction of a wheel spacing based at least on the data provided by the first and second sensors. Brief description of the drawings
[0025] The invention will be better understood upon reading the following description of exemplary embodiments, with reference to the accompanying drawings in which:
[0026] [Fig. 1] represents a side view of a load handling device according to the invention,
[0027] [Fig.2] represents, in side view, the angular deflection of the arm of the device of the [Fig.l],
[0028] [Fig.3] represents, in side view, the angular displacement of the tool of the machine of the [Fig.l],
[0029] [Fig.4] represents a side view of the device of [Fig.1] to illustrate the extension in length of the telescopic arm,
[0030] [Fig.5] represents, in lateral view, a possible movement zone of the tool the device of [Fig.1],
[0031] [Fig.6] shows, in lateral view, the safety perimeters around the tool and the wheels in an initial configuration of the vehicle, and
[0032] [Fig.7] is a view similar to [Fig.6] in which the craft is in a second configuration.
[0033] In the following description, identical elements or elements with identical functions bear the same reference numeral. For the sake of brevity, they are not described opposite each figure; only the differences between the embodiments are described.
[0034] In the figures, the actual proportions have not always been respected, for the sake of clarity.
[0035] Figures 1 to 7 illustrate an example of a load handling device 1 according to the invention.
[0036] The device 1 comprises a chassis 2 mounted on wheels 3, in this example four, allowing its movement on the ground.
[0037] An arm 4 is carried by the chassis 2 and extends along a longitudinal axis XX'. The arm 4 is mounted on the chassis 2 pivotally about an axis orthogonal to the longitudinal axis of the arm by means of a first actuator 5, for example formed of one or more cylinders, allowing the angular displacement of the arm 4 between a low position PB and a high position PH, as illustrated in [Fig.2].
[0038] At a free end 7 of the arm 4 is a tool 6 mounted pivotally around an axis 9 orthogonal to the longitudinal axis XX' of the arm 4, by means of a second actuator 8, for example formed of one or more cylinders.
[0039] The tool 6 can be moved between a close position PR of the wheels 3 and a far position PE of the wheels 3, as illustrated in [Fig. 3]. When the tool 6 is a bucket, the close position PR of the wheels 3 and the far position PE of the wheels 3 can also be respectively called the digging position and the dumping position.
[0040] In this example, the arm 4 of the device 1 is adjustable in length, with a third actuator 10, for example formed by one or more cylinders, allowing the length of the arm 4 to be adjusted between a minimum length Tmini and a maximum length Tmaxi. The arm 4 is therefore a telescopic arm.
[0041] The combination of the first, second and third actuators 5, 8, 10 defines a possible positioning zone 30 of the tool 6, illustrated in [Fig.5].
[0042] The device 1 is equipped with a first sensor 11 that determines the angular position of the arm 4 between the upper position PH and the lower position PB. The first sensor 11 is, for example, a potentiometer or a Hall effect sensor. A second sensor 12 determines the angular position of the tool 6 between the close position PR and the wide position PE of the wheels 3. The second sensor 12 is, for example, a potentiometer or a Hall effect sensor. A third sensor 13 is provided to determine the length T of the arm 4. The third sensor 13 is, for example, a potentiometer or a Hall effect sensor.
[0043] A drive element 14, such as a joystick, allows the operator of the machine 1 to control the movement of the arm 4, in pivoting and length, and of the tool 6 via the first, second and third actuators 5, 8, 10.
[0044] A control unit 15 is configured to control the various actuators based on data provided by the drive element 14 and the sensors 11, 12, and 13. This control unit 15 is in the form of an electronic and computer system that includes, for example, a microprocessor and working memory. In one particular configuration, the control unit may be in the form of a programmable logic controller (PLC). In other words, the functions and steps described may be implemented either as a computer program or via hardware components (e.g., programmable gate arrays).In particular, the functions and steps performed by the control unit or its modules can be carried out by instruction sets or computer modules implemented in a processor or controller or be carried out by dedicated electronic components or components of the type of programmable logic circuit (or FPGA which is the acronym for the English field-programmable gate array, which literally corresponds to network. Programmable in-situ gates) or application-specific integrated circuits (ASICs) are used. It is also possible to combine computer and electronic components. When it is specified that the unit, or means or modules of said unit, are configured to perform a given operation, this means that the unit includes computer instructions and the corresponding execution means to perform said operation, and / or that the unit includes corresponding electronic components.
[0045] The control unit 15 is also configured to control the automatic stopping of the second actuator 8 or the automatic actuation of the second actuator 8 to move the tool 6 in the direction of a wheel spacing 3 according to the data provided by the sensors 11, 12 and 13, in order to maintain the tool 6 at a distance from the wheels 3 greater than a predetermined value.
[0046] When the drive member 14 is actuated, the control unit 15 can automatically stop the second actuator 8 or actuate it to move the tool 6 in the direction of a spacing of the wheels 3 when the values of the sensors 11, 12 and 13 correspond to a pair of predetermined stored values, corresponding to a distance between the tool 6 and the wheels 3 equal to a predetermined value.
[0047] In particular, the control unit 15 automatically controls the stopping or actuation of the second actuator 8 to move the tool 6 in the direction of a wheel spacing 3 only when the length T of the arm 4 is between the minimum length Tmini and an intermediate length Tl between the minimum length Tmini and the maximum length Tmaxi, when the position of the arm 4 is between the low position PB and an intermediate position PiB between the low position PB and the high position PH and when the position of the tool 6 is between the close position PR of the wheels 3 and an intermediate position PiO between the close position PR and the spread position PE.
[0048] The three conditions described above, when met, define a positioning zone for the tool 6, referred to as the danger zone 31, which is included within the possible positioning zone 30 of the tool 6, as illustrated in [Fig. 5]. Thus, the control unit 15 automatically controls the stopping or activation of the second actuator 8 to move the tool 6 in the direction of a wheel spacing 3 only when the tool 6 is in the danger zone 31. The danger zone 31 is not a prohibited area where the tool 6 should not be located, but an area where there is a risk of collision between the wheels 3 and the tool 6.
[0049] When the second actuator 8 is a cylinder, the control unit can be configured to control automatically, based on the data provided by sensors 11, 12 and 13, the stop of the cylinder in the direction of a retraction or an extension, or the reversal of the movement of the cylinder.
[0050] A first predetermined safety perimeter E can be defined around the tool 6. Similarly, a second predetermined safety perimeter P can be defined around the wheels 3. The perimeters E and P are illustrated in figures 6 and 7.
[0051] As illustrated, the tool 6 is enclosed within the predetermined safety perimeter E around the tool 6 and at a distance from it, and the wheels 3 are enclosed within the predetermined safety perimeter P around the wheels 3 and at a distance from it.
[0052] The control unit can automatically control the stopping or actuation of the second actuator 8 to move the tool 6 in the direction of a wheel spacing 3 according to the data provided by the sensors 11, 12 and 13, in order to maintain the first predetermined safety perimeter E around the tool 6 at a distance from the second predetermined safety perimeter P around the wheels 3 greater than a predetermined xmin value.
[0053] The predetermined xmin value to be maintained between the safety perimeter E around the tool 6 and the safety perimeter P around the wheels 3 is for example between 0 mm and 500 mm.
[0054] A method of driving the load handling device 1 as illustrated includes the automatic stopping of the second actuator 8 or the automatic actuation of the second actuator 8 to move the tool 6 in the direction of a wheel spacing 3 according to the data provided by the sensors 11, 12 and 13.
[0055] According to one embodiment of the invention, the control unit is configured to transmit an alert, in particular an auditory, visual or haptic alert, when it automatically commands the stopping of the first actuator 5 and / or the second actuator 8 or automatically commands the actuation of the first actuator 5 and / or the second actuator 8.
[0056] In the following, various examples of control of the second actuator 8 are described.
[0057] In a first example, illustrated in [Fig. 6], the distance x between the predetermined safety perimeter E around the tool 6 and the second predetermined safety perimeter P is much greater than the predetermined value xmin. In this case, the operator is free to perform all possible movements of the tool 6 and the arm 4.
[0058] In a second example, illustrated in [Fig. 7], during movements controlled by the operator of the device 1, the predetermined safety perimeter E around the tool 6 is at a distance from the second predetermined safety perimeter P equal to the predetermined value xmin. In this case, several scenarios are possible.
[0059] In a first case, the operator commands a movement of the second actuator 8 towards the close position PR of the wheels 3. The control unit will automatically command the stop of the second actuator 8.
[0060] In a second case, the operator commands a pivoting movement of the arm 4 towards the lowered position and / or a movement of the third actuator 10 towards the minimum length Tmini. The control unit will automatically command the second actuator 8 to pivot it towards the extended position PE of the wheels 3. The different movement commands on the first and third actuators 5 and 10 remain unchanged by the control unit.
[0061] For example, if the operator commands a movement of the tool 6 in a direction close to the wheels 3, and a pivoting movement of the arm 4 towards the low or high position and / or a movement of the third actuator 10 towards the minimum length Tmin, the control unit will automatically command the second actuator 8 to pivot it towards the position PE away from the wheels 3. If the operator commands a movement of the tool 6 in a direction close to the wheels 3 while the lifting or lowering movement of the arm 5 tends to move the tool 6 away from the wheels, a movement of the tool 6 in a direction close to the wheels 3 is again permitted while maintaining the predetermined distance xmin to be maintained between the safety perimeter E around the tool 6 and the safety perimeter P around the wheels 3.
[0062] In another example, if the operator commands a movement of the tool 6 in a direction close to the wheels 3, and a movement of the third actuator 10 towards the maximum length Tmaxi, the control unit will automatically stop the second actuator 8. If the operator commands a movement of the tool 6 in a direction close to the wheels 3 while the extension movement of the arm 5 tends to move the tool 6 away from the wheels, a movement of the tool 6 in a direction close to the wheels 3 is again permitted while maintaining the predetermined distance xmin to be maintained between the safety perimeter E around the tool 6 and the safety perimeter P around the wheels 3.
[0063] In a third case, the operator commands a movement of the tool 6 in a direction opposite to the wheels 3. This can occur by a movement command of the second actuator 8 towards the offset position PE of the wheels 3, and / or a command of the first actuator 5 towards the high position and / or a command of the third actuator 10 towards maximum length Tmaxi. No automatic action of the control unit is carried out.
[0064] The invention is not limited to the example just described.
[0065] In particular, the drive unit can be a programmable logic controller.
[0066] The control unit can be configured to automatically control the stopping of the first actuator and / or the second actuator and / or the third actuator or to automatically control the actuation of the first actuator and / or the second actuator and / or the third actuator to drive the tool in the direction of a wheel spacing based on at least the data provided by the first, second and third sensors to allow the tool to be kept at a distance from the wheels greater than a predetermined value.
Claims
Demands
1. A load-handling device (1) comprising a chassis (2), ground-moving drive wheels (3) of the chassis (2), an arm (4) carried by said chassis (2) extending along a longitudinal axis (XX') and mounted by means of a first pivotable actuator (5) between a lower position (PB) and a higher position (PH), a tool (6) disposed at a free end (7) of the arm (4), this tool (6) being mounted by means of a second pivotable actuator (8) about an axis (9) orthogonal to the longitudinal axis (XX') of the arm (4) between a close (PR) position of the wheels (3) and a far (PE) position of the wheels (3), a first sensor (11) for determining the angular position of the arm (4) between the high and low positions, a second sensor (12) for determining the angular position of the tool (6) between the close and far positions of the wheels (3),a drive element (14) for the movement of the arm (4) and the tool (6), the drive element being actuable by the operator of the machine (1) or being a programmable logic controller, a control unit (15) configured to control the first and second actuators (5; 8) according to the data provided by said drive element and the first and second sensors (11; 12), characterized in that the control unit is configured to automatically control the stopping of the first actuator (5) and / or the second actuator (8), or to automatically control the actuation of the first actuator (5) and / or the second actuator (8) to drive the tool (6) in the direction of a wheel spacing (3), according at least to the data provided by the first and second sensors (11; 12) to allow the tool (6) to be maintained at a distance from the wheels (3) greater than a predetermined value.
2. Load handling device (1) according to the preceding claim, characterized in that the control unit (15) is configured to, in the actuated state of the drive member (14), automatically control the stopping of the first actuator (5) and / or the second actuator (8) or automatically control the actuating of the first actuator (5) and / or the second actuator (8) to move the tool (6) in the direction of a wheel spacing (3), when the values of the first and second sensors (11; 12) correspond to a pair of predetermined stored values, this pair of predetermined values corresponding to a distance between the tool (6) and the wheels (3) equal to a predetermined value.
3. Load handling device (1) according to any one of the preceding claims, characterized in that the pilot unit (15) is configured to, in the actuated state of the drive member (14), automatically control the stopping of the first actuator (5) and / or the second actuator (8) or automatically control the actuation of the first actuator (5) and / or the second actuator (8) to drive the tool (6) in the direction of a wheel spacing (3) only when the position of the arm (4) is between the lower position (PB) and an intermediate position of the arm (PiB) between the lower position (PB) and the upper position (PR).
4. Load handling device (1) according to any one of the preceding claims, characterized in that the pilot unit (5) is configured to, in the actuated state of the drive member (14), automatically control the stopping of the first actuator (5) and / or the second actuator (8) or automatically control the actuation of the first actuator (5) and / or the second actuator (8) to drive the tool (6) in the direction of a wheel spacing (3) only when the position of the tool (6) is between the close position (PR) of the wheels (3) and an intermediate position of the tool (PiO) between the close position (PR) of the wheels (3) and the spread position (PE) of the wheels (3).
5. Load handling device (1) according to any one of the preceding claims, characterized in that the arm (4) is an adjustable-length arm (4), in that the device (1) comprises a third actuator (10) for adjusting the length of the arm (4) between a minimum length (Tmini) and a maximum length (Tmaxi), the device (1) comprising a third sensor (13) for determining the length (T) of the arm (4), and in that the control unit (15) is configured to automatically control the stopping of the first actuator (5) and / or the second actuator (8) or to automatically control the actuation of the first actuator (5) and / or the second actuator (8) to drive the tool (6) in the direction of a wheel spacing (3) according to at least the data provided by the first, second and third sensors (11; 12; 13) to allow the tool (6) to be kept at a distance from the wheels greater than a predetermined value.
6. Load handling device (1) according to the preceding claim, characterized in that the pilot unit (15) is configured to, in the actuated state of the drive member (14), automatically control the stopping of the first actuator (5) and / or the second actuator (8) or automatically control the actuation of the first actuator (5) and / or the second actuator (8) to drive the tool (6) in the direction of a wheel spacing (3) only when the length (T) of the arm (4) is between the minimum length (Tmini) and an intermediate length (Tl) of the arm (4) between the minimum length (Tmini) of the arm (4) and the maximum length (Tmaxi).
7. Load handling device (1) according to any one of the preceding claims, characterized in that the second actuator (8) is a cylinder and in that the control unit is configured to, in the actuated state of the drive member (14), automatically control, based at least on the data provided by the first and second sensors (11; 12), the stop in operation in the direction of a retraction or an extension of the cylinder of the second actuator (8) and / or the reversal of the movement of the cylinder of the second actuator (8).
8. Load handling device (1) according to any one of the preceding claims, characterized in that the control unit (15) is configured to automatically control the stopping of the first actuator (5) and / or the second actuator (8) or to automatically control the actuation of the first actuator (5) and / or the second actuator (8) to drive the tool (6) in the direction of a wheel spacing (3) according to at least the data provided by the first and second sensors (11; 12) to allow the maintenance of a first predetermined safety perimeter (E) around the tool (6) at a distance (x) from a second predetermined safety perimeter (P) around the wheels (3) greater than a predetermined value.
9. Load handling device (1) according to the preceding claim, characterized in that the tool (6) is enclosed within the predetermined safety perimeter (E) around the tool (6), the tool (6) being at a distance from the predetermined safety perimeter (E) around the tool (6), and in that the wheels (3) are enclosed within the predetermined safety perimeter (P) around the wheels (3), the wheels (3) being at a distance from the predetermined safety perimeter (P) around the wheels (3).
10. Load handling device (1) according to the preceding claim, characterized in that the predetermined value to be maintained between the predetermined safety perimeter (E) around the tool (6) and the predetermined safety perimeter (P) around the wheels (3) is for example between 0 mm and 500 mm.
11. Load handling device (1) according to the preceding claim, characterized in that only the second actuator (5) is automatically controlled to maintain the tool (6) at a distance from the wheels (3) greater than a predetermined value
12. A method for controlling a load handling machine (1) characterized in that the load handling machine (1) conforming to any one of the preceding claims, the method includes the automatic stopping of the first actuator (5) and / or the second actuator (8) or the automatic actuation of the first actuator (5) and / or the second actuator (8) to drive the tool (6) in the direction of a wheel spacing (3) as a function of at least the data provided by the first and second sensors (11; 12).