Handling machine comprising a chassis inclination sensor system and corresponding control method

Abstract

The invention relates to a load handling machine (1) or person handling machine (1), the maximum permitted controlled speed (Vwcmax) of which is limited, in working mode, as a function of the angle of inclination (A) of the machine, such that, over at least part of an angular range, the maximum permitted setpoint speed decreases until a zero speed value is reached when the measured angle of inclination of the chassis (2) reaches the maximum angle value of said angular range.

Description

Description Title of the invention: Handling machine comprising a chassis tilt sensor system and corresponding control method

[0001] FIELD OF THE INVENTION

[0002] The present invention relates generally to handling machines, comprising a chassis tilt sensor system.

[0003] PREVIOUS ART

[0004] As an example of handling machines, the state of the art includes lifting machines with a basket (elevating machine) intended for lifting people which serve to facilitate access to a work area at height.

[0005] Such a machine usually comprises a rolling chassis equipped with a power unit. The chassis may accommodate a turret which carries, by means of a movement mechanism, a lifting structure, such as a lifting arm system, at the end of which is coupled a work platform, in which an operator is located. The work platform is in the form of a work floor equipped with guardrails to protect against the risk of falls.

[0006] The work platform is usually equipped with a machine control interface, such as a control panel, which allows the operator to control the lifting and lowering movement of the lifting structure and the ground movement of the machine.

[0007] It is desirable to be able to stop the machine from moving on the ground when the chassis tilt limit is reached so as not to exceed the tilt limit and risk the machine tipping over. However, it is noted that there is a risk of tipping over when the machine is stopped.

[0008] It is understood that a stability problem may also arise for other types of handling machines, such as telescopic arm trucks, in particular when the handling system carried by the chassis of the machine, which for example comprises a telescopic arm, is in an extended, raised or extended configuration which increases the instability of the machine compared to the folded, lowered or retracted configuration of the handling system.

[0009] Document US2017081162 discloses a scissor lift comprising a tilt sensor. It is provided that, beyond a given slope angle and when the machine platform is completely lowered (and therefore in the transport position), the machine can move but at reduced speed.

[0010] Document US2023079946 describes a nacelle that includes a tilt sensor. In the transport position of the machine, the machine controller can limit the speed of the machine to a predetermined speed when the slope is greater than a given threshold.

[0011] The aim of the present invention is to propose a new machine and a new corresponding method making it possible to overcome all or part of the problems set out above.

[0012] SUMMARY OF THE INVENTION

[0013] To this end, the invention relates to a load or person handling machine, comprising: - a rolling chassis; - a motorized system for driving the chassis on the ground; - a chassis tilt sensor system for measuring a chassis tilt angle; - a handling system which is capable of taking different configurations in space relative to the chassis; - a processing unit for controlling the motorized drive system for moving the chassis on the ground; - a speed control system, such as a joystick, for transmitting a movement speed instruction to the processing unit. machine floor; - a control system, such as a joystick, of the handling system for controlling its configuration in space; the processing unit being configured to operate the machine in two distinct modes, comprising: - a mode called work mode for which the handling system is in a first spatial configuration called work, for example deployed at height, and - a mode called transport mode for which the handling system is in a second spatial configuration, for example folded or retracted, for which the machine has greater stability than in said working configuration of the handling system of the machine; the processing unit is configured to, in working mode, define a maximum authorized value of commanded speed for the movement on the ground of the machine which is a function of the measured angle of inclination of the chassis, said maximum authorized value of commanded speed being decreasing, preferably continuously, when, in absolute value, the angle of inclination increases from a given value of inclination, which may be zero, towards a maximum angle value which is greater than said given value of inclination, the maximum authorized value of commanded speed being zero for said maximum angle of inclination value.

[0014] In other words, said maximum permitted value of commanded speed is decreasing (decreases), preferably continuously, when the angle of inclination increases from a given positive inclination value, which may be zero, towards a maximum positive angle value greater than said given inclination value.

[0015] In working mode, the curve of the maximum authorized value of commanded speed defined as a function of the angle of inclination of the chassis, comprises at least one portion which has a downward slope (curve) over a range of positive angle of inclination values. Advantageously, the decrease in the maximum authorized value of commanded speed is continuous over said positive angular range. It may be provided that the decrease takes place continuously over said given positive angular range, noted [Aw1 - Awmax [, with Aw1 the angle from which the maximum authorized commanded speed value decreases and Aw ma x the maximum chassis tilt angle (for which the maximum permitted commanded speed value is zero), so as to reduce the maximum permitted commanded speed value to a speed Vw0_r, preferably corresponding to a percentage of the maximum permitted command speed value for a zero tilt angle, for example a speed Vw0_r equal to 0.9*Vw0, just before the machine chassis tilt angle reaches the angle Aw ma x, then that when the angle reaches Aw ma x, then the maximum allowed value of commanded speed changes from Vw0_r to 0.

[0016] The angular range of inclination of the chassis along which said maximum permitted value of commanded speed is decreasing has a non-zero width (gap between the ends of the range), preferably a function of the angle Aw max, which allows, in work mode, to anticipate the deceleration of the machine before it stops. In work mode, which is more unstable than transport mode, the progressive decrease in the maximum authorized value of commanded speed, with the increase in chassis inclination, allows a progressive and controlled stopping of the machine, which limits the risk of tipping. Such a design of the handling machine allows a stop of movement on the ground of the handling machine without exceeding a maximum inclination threshold. This threshold can be a maximum tilt threshold (i.e. a lateral inclination threshold) or a longitudinal inclination threshold. It is also possible to provide that the inclination threshold includes a combination of longitudinal and lateral inclination threshold. The movement on the ground of the machine includes the forward and backward movement of the machine.

[0017] The gradual reduction in the maximum authorized commanded speed value for ground movement of the handling machine as the chassis tilt angle increases, makes it possible to slow down the ground movement of the machine before reaching the maximum authorized chassis tilt angle. Slowing down the machine makes it possible to effectively anticipate the stop to avoid a sudden movement of the machine which could risk destabilizing the machine.

[0018] Conversely, in state-of-the-art solutions, the stop is made abruptly when the threshold tilt angle is reached, without anticipation, which risks causing the machine to tip over. In addition, it is observed that with state-of-the-art machines, when the maximum authorized chassis tilt threshold is reached and a ground movement stop command is triggered, the maximum authorized chassis tilt threshold is ultimately often exceeded due to the inertia of the machine. This can cause problems of instability and stalling of the turret rotation when it is present.With the machine according to document US2017081162, in the event that the machine could be moved into the working position for a slope value lower than a given maximum angle value, a sudden stop of the machine would occur if the maximum slope angle was reached while the machine was moving into the working position because under these conditions the only operation permitted, as described in document US2017081162, is then moving into the transport position.

[0019] It will be noted that the processing unit modifies the maximum authorized value of the commanded ground travel speed of the machine according to the measured chassis tilt angle, but that the processing unit allows the operator, or a control program in the context of an autonomously driven machine, to act on the control of the ground travel speed of the machine which nevertheless remains limited by said maximum authorized value of the commanded ground travel speed itself defined according to the measured chassis tilt angle. In other words, the processing unit sets the maximum value of the commanded speed according to the measured chassis angle: the commanded travel speed of the machine can then vary between a zero value and said maximum value which has been defined according to the measured chassis angle.

[0020] In one particular aspect, the working position differs from the transport position by the height of the platform (or basket). In the working position, the platform is higher than in the transport position so that the risk of tipping during braking is all the greater and must be managed more gradually than during braking or stopping in the transport position.

[0021] According to a preferred embodiment, the processing unit is configured to modify the maximum authorized value of the commanded speed in the direction of a reduction when the inclination value of the chassis exceeds a given inclination value.

[0022] In other words, the maximum authorized value of the commanded speed is reduced when the inclination of the chassis exceeds a first inclination value so that it approaches the maximum authorized inclination value, i.e. if, in absolute value, the difference between the measured chassis inclination angle and the maximum authorized inclination value is less than a given threshold value (in other words, if the distance or difference between the measured chassis inclination angle and the maximum authorized inclination value is less than a given threshold value). As long as the difference is sufficient, i.e. greater than or equal to the given threshold value, it can be provided that the processing unit is configured to maintain the maximum authorized value of the commanded speed at a constant value (i.e. a level).

[0023] According to one embodiment, for a chassis tilt angle that progresses from a first given tilt value to the maximum authorized tilt value, the maximum authorized value of the commanded speed evolves according to a downward (i.e. negative) slope (of the curve), for example a downward slope (of the curve) of constant value, preferably without depending on external conditions (other than conditions impacting the chassis angle). For example, the maximum authorized commanded speed value does not depend on the state of friction of the ground, but of course depends on the inclination of the ground since this has an impact on the inclination of the chassis relative to the horizontal plane.

[0024] The reduction curve of the maximum permitted value of the commanded speed can be adjusted according to the inertia of the machine and / or according to a latency time of the stop control system when moving the machine on the ground.

[0025] The machine may also include one or more of the following characteristics taken in any technically admissible combination.

[0026] According to one embodiment, the decreasing portion of the curve of the maximum authorized commanded speed value defined as a function of the chassis tilt angle is a straight line segment.

[0027] According to one embodiment, the angle Aw1 from which the maximum authorized commanded speed value decreases is a percentage of the maximum angle Awmax. For example, the angle Aw1 is between 0.9*Aw ma x and 0.1 * Aw ma x.

[0028] According to one embodiment, the maximum tilt angle of the chassis Aw ma x is preferably between 1.5° and 6°, for example 5°.

[0029] According to a particular aspect, tests on the machine are carried out to verify that, in operation and in particular when moving the machine in the work configuration (mode), the machine remains stable when the angle of the chassis reaches an angle of value equal to Aw ma x + 0.5 °. The gradual reduction of the maximum permitted commanded speed value before reaching the maximum angle Aw ma x prevents the machine from exceeding by inertia an angle equal to the maximum angle Awmax + 0.5°.

[0030] According to one embodiment, the maximum authorized commanded speed value for a chassis tilt angle of 0°, noted VwO, is less than or equal to 0.7 m / s, and not zero, preferably greater than or equal to 0.05 m / s.

[0031] According to one embodiment, in working mode, the difference between the value of the maximum inclination angle Aw max for which the maximum authorized commanded speed value is zero (stop), and the value of the angle of inclination Aw1 from which the maximum authorized commanded speed value decreases is at least equal to 0.5 °.

[0032] According to one embodiment, in work mode, the maximum authorized commanded speed value just before reaching the maximum angle Awmax, noted Vw0_r, is between 0.05*Vwo and 0.5*Vwo, with Vwo the maximum authorized commanded speed value in work mode for a chassis tilt angle of 0°.

[0033] According to one embodiment of the invention, the processing unit is configured to, in transport mode, define a maximum authorized value of commanded speed for the ground movement of the machine which is non-zero. within a given angular range which includes said maximum angle value defined for the working mode.

[0034] According to an embodiment of the invention, in which the processing unit is configured to, in transport mode, define a maximum authorized value of commanded speed for the ground movement of the machine which is a function of the measured angle of inclination of the chassis, and which decreases when the angle of inclination increases from a given inclination value, which may be zero, towards a maximum angle value.

[0035] According to one embodiment of the invention, said maximum angle value in transport mode is greater than the maximum angle value in work mode.

[0036] According to one embodiment of the invention, in work mode, when the chassis tilt angle reaches the maximum value, so that the machine comes to a standstill, the processing unit is configured to allow the machine to switch from work mode to transport mode by command from the handling system, the processing unit being configured to, when the machine is in transport mode, authorize the vehicle to move on the ground up to a maximum chassis tilt angle which is greater than the maximum chassis tilt angle defined in work mode, so as to allow the machine to return to an area of the ground for which the chassis angle is less than the maximum chassis tilt value defined in work mode.

[0037] According to one embodiment of the invention, the speed control system comprising a manual speed control member operable over a given stroke, such as a joystick, the processing unit is configured to, in response to the driver actuating said manual control member, control the motorized drive system for moving the chassis on the ground, to move the machine according to a commanded speed value which is less than or equal to said maximum value authorized in work mode and which is defined as a function of the position of the manual control member.

[0038] According to one embodiment of the invention, following the movement of the manual control member to control the speed, the processing unit defines the value of the commanded speed by multiplying the maximum authorized value of the speed controlled by the ratio between the stroke traveled by the manual control member and the total available stroke of said manual control member.

[0039] According to one embodiment of the invention, the processing unit is configured to, over the angular range [0; Aw1] of inclination of the chassis, the value Aw1 being (in absolute value) less than the maximum angle value Awmax, define the maximum authorized value of commanded speed for the movement on the ground of the machine in work mode, as being equal to a constant value.

[0040] According to one embodiment of the invention, the handling system carried by the chassis comprises a set of arms articulated together and a platform coupled to said set of arms, said set of arms being capable of taking a deployed configuration in height, according to which the work mode is activated, and a folded configuration according to which the transport mode is activated.

[0041] According to one embodiment of the invention, the machine comprises a turret rotatably mounted on the chassis around an axis orthogonal to the ground support plane of the wheels of the machine, the handling system being carried by the turret.

[0042] The invention also relates to a method of controlling a machine according to any of the preceding embodiments, said method comprising the following steps: - control of the handling system, in the sense of deployment or output of an element of the handling system, so that the processing unit determines that the machine is in work mode; - from a given chassis tilt angle value, which may be zero, reduction of the maximum permitted value for the commanded machine travel speed when, in absolute value, the measured chassis tilt angle increases; - control of the machine's travel speed to a value less than or equal to the maximum authorized value; - reaching the maximum chassis tilt angle defined for the work mode so that the maximum permitted value for the travel speed ordered is null; - control of the handling system, in the sense of a withdrawal or retraction of an element of the handling system, so that the processing unit determines that the machine is in transport mode; - movement of the machine in said transport mode to reach an area for which the measured tilt angle of the chassis falls below the maximum tilt value defined for the work mode; - preferably, control of the handling system to return to work mode.

[0043] The reduction in the maximum authorized commanded speed value can thus be carried out in an anticipated and progressive manner when the machine is in work mode, until reaching the stop of movement on the ground when the inclination sensor measures an angle equal to the maximum authorized inclination threshold, in order to avoid a sudden stop which could cause the machine to tip over.

[0044] BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Other characteristics and advantages of the invention will emerge from the following description, which is purely illustrative and non-limiting and must be read in conjunction with the appended drawings, in which:

[0046] - [Fig. 1] Figure 1 is a schematic view of a handling machine according to an embodiment of the invention, the chassis of the machine having a first inclination value (which may correspond to the angle of inclination of the ground relative to the horizontal when the ground is flat and the machine is supported by its wheels on this ground), so that the chassis has a first inclination value and the maximum authorized value of the commanded ground travel speed is limited to a first given value, the machine being in work mode;

[0047] - [Fig. 2] Figure 2 is a schematic view of the machine of Figure 1, the chassis of the machine having a second inclination value which is greater than the first inclination value of Figure 1, so that the maximum permitted value of the commanded ground travel speed is limited to a second given value which is less than the first value, the machine being in work mode;

[0048] - [Fig. 3] Figure 3 is a graph giving, for each of two operating modes of the machine, namely a work mode and a transport mode, a control law of the maximum authorized value of the commanded ground travel speed of the machine, as a function of the angle of inclination of the chassis of the machine, for a machine according to an embodiment of the invention, such as the machine of Figure 1, the maximum authorized value of the commanded speed being, in absolute value, preferably constant up to a certain angle of inclination of the chassis, then decreasing until reaching a zero value for the maximum authorized angle of inclination of the chassis;

[0049] - [Fig. 4] Figure 4 is a flowchart giving steps of a method for controlling a handling machine according to one embodiment.

[0050] DETAILED DESCRIPTION

[0051] Embodiments of the invention are described below with reference to the accompanying drawings. In the drawings, the size and relative sizes of the elements may be exaggerated for clarity. Like numerals refer to like elements throughout the drawings. However, the invention may be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein.

[0052] A reference throughout the specification to "an embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the present invention. Thus, the occurrence of the phrase "in an embodiment" at various locations throughout the specification does not necessarily refer to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0053] A machine 1 for handling loads or people is proposed, comprising a handling system 4 carried by a chassis 2 directly or indirectly, the risk of instability of which is reduced when the handling machine stops moving on the ground while the machine is in work mode, thanks to a reduction in the maximum authorized value of the speed. ground movement command as the chassis tilt approaches a maximum permissible tilt value (threshold value).

[0054] Handling machine

[0055] With reference to the figures, a handling machine 1 of the basket type is shown, allowing work to be carried out by lifting people.

[0056] Alternatively, the handling machine may be another type of handling machine, such as a telescopic arm forklift whose arm may be equipped with a work tool, such as a bucket or forks, or with a platform for an operator to work at height.

[0057] Thus the remainder of the description given in the case of a nacelle applies to other types of handling machine comprising a load or person handling system which is capable of selectively presenting a deployed, or raised or extended configuration, depending on the type of handling system, and a folded, or lowered or retracted configuration (depending on the type of handling system), which provides the machine with better stability than the deployed, or raised or extended configuration.

[0058] The nacelle 1 comprises a rolling chassis 2 equipped with a motor system 12 for driving the chassis 2 on the ground. The motor system may be of the thermal or electric type.

[0059] At least some of the wheels are steered wheels, having a variable orientation relative to the chassis 2, to enable the nacelle to be steered 1. The chassis is equipped with a steering wheel control system.

[0060] According to one embodiment of the invention and as illustrated in Figures 1 and 2, the chassis 2 carries a turret 3 pivotally mounted around an axis orthogonal to the ground support plane of the wheels of the machine. Thus the pivot axis of the turret is vertical when the machine is supported by its wheels on a horizontal ground.

[0061] The turret 3 carries a handling system 4 which comprises a lifting structure 5 which is provided with a working platform 7 on which an operator can be present.

[0062] The platform 7 is equipped with a control console 11. The control console 11 comprises a first control member 11 A, such as a joystick, which makes it possible to control the movement of the machine on the ground, and a second control member, such as a joystick, which makes it possible to control the handling system and in particular the deployment and folding of the lifting structure. It is possible to provide for the first control member and the second control member to be produced by the same member that can be actuated differently depending on the desired function or two separate members.

[0063] The control console 11 thus allows the operator to transmit to the processing unit 10 instructions for controlling the movement of the chassis on the ground and / or instructions for lifting or lowering the handling system or parts of said system, such as the platform 7.

[0064] Elevation structure

[0065] The lifting structure 5 extends between the turret 3, when present, and the platform 7. The lifting structure 5 may comprise a set of arms 6 articulated to each other and to the chassis, via the turret if applicable. As in the example illustrated in the figures, the platform 7 may be mounted on a pendulum system 69 articulated to the end of a lifting arm 68 (which may be telescopic) of the lifting structure 5. The lifting arm 68 may itself be articulated to another part 67 of the lifting structure comprising one or more other arms, such as a set of arms arranged in a parallelogram, which can be articulated relative to the chassis (via the turret 3 if applicable). The elements 67, 68, 69 may be considered as part of the set of arms 6.

[0066] The lifting (deploying) and lowering (folding) movement of the lifting structure 5 is made possible by a system of jacks arranged with the lifting structure 5 to fold or deploy the lifting structure 5.

[0067] The cylinder system may be hydraulic or electric. In the case of a hydraulic cylinder system, a hydraulic circuit system (not shown) is used to power the hydraulic cylinder system. The hydraulic circuit system usually includes a cylinder system power supply circuit and an oil pressurization system, such as a pump, actuable by a motor. Said motor may be wholly or partly shared with a motor of the ground-based drive system or be a separate motor. The processing unit makes it possible to control the hydraulic circuit system to control the power supply to the cylinder system.

[0068] Chassis tilt

[0069] The machine comprises a tilt sensor system 19 for measuring, preferably in real time, an angle A of tilt of the chassis 2 relative to the horizontal (preferably a longitudinal and / or lateral tilt of the chassis relative to the horizontal plane). "In real time" means that the tilt measurement is carried out during operation of the machine, at a given frequency, for example 100 Hz.

[0070] Generally speaking and as illustrated in Figures 1 and 2, preferably from a given angle of inclination, for example At1 or AW1, for an angle of inclination of the chassis which has a first value A1 (Figure 1) then a second value A2 (Figure 2) greater than A1, the maximum authorized value of the commanded speed V2 defined for the angle A2 is less than the maximum authorized value of the commanded speed V1 defined for the angle A1.

[0071] As recalled above, the machine comprises a processing unit 10 for controlling the drive system 12 in movement of the chassis on the ground, to move the machine at a commanded speed. A commanded speed signal can be supplied to the processing unit by actuation of the control member 11 A of the control panel 11, such as a joystick, connected to the processing unit 10. Preferably, the signal is representative of the actuation travel of the member. It can thus be provided that a movement of X% of the member over its available travel is interpreted by the processing unit 10 as a speed command at X% of the maximum authorized value of the speed.

[0072] As detailed below, the processing unit 10 adapts the value of the maximum authorized commanded speed as a function of the measured value of the angle A of inclination of the chassis 2 for at least part of the authorized angular range of inclination.

[0073] The angle of inclination of the chassis may include the angle, called the lateral inclination angle, formed by a normal to the ground support plane of the wheels of the machine with the vertical in a plane which passes through said vertical and a lateral horizontal axis of the machine (i.e. a lateral horizontal axis orthogonal to the longitudinal axis of the machine).

[0074] In addition or as a variant, the chassis tilt angle may include the angle, called the longitudinal tilt angle, formed by a normal to the ground support plane of the machine's wheels with the vertical in a plane passing through the vertical and a longitudinal axis of the machine (i.e. a front-rear movement axis of the machine). For a vehicle comprising two front wheels and two rear wheels, the longitudinal axis of the machine is the axis parallel to the ground support plane of the machine's wheels and which passes between the two rear wheels and between the two front wheels of the vehicle.

[0075] It can thus be predicted that the angle of inclination is the lateral angle of inclination or the longitudinal angle of inclination or the resultant of the combination of the two angles.

[0076] Operating modes

[0077] The lifting structure 5 is capable of taking a deployed and / or height configuration adapted to the work, in particular at height, of the operator present on the platform 7, called work mode, and a folded configuration, relative to said deployed, and / or lowered configuration, adapted to the transport of the machine, called transport mode, more stable than in work mode.

[0078] The processing unit may be configured to determine that the machine is in work mode or transport mode based on data from a position sensor system, for example an angular position or arm extension sensor, all or part of the handling system, and / or a turret orientation sensor.

[0079] It is understood that the transport mode can be defined for a partially deployed configuration of the handling system, and that the work mode can be defined for a partially folded configuration of the handling system. In transport mode, the handling system is in a folded configuration and / or lowered, more stable compared to the deployed and / or raised configuration corresponding to the work mode.

[0080] The processing unit 10 is thus configured to operate the machine in two distinct modes. The two distinct modes comprise a mode called work mode for which the handling system 4 is deployed and / or raised, and a mode called transport mode for which the handling system 4 is folded and / or lowered, more stable than in work mode.

[0081] Thus, it can be expected that in transport mode (movement), the lifting structure 5 is in a folded configuration (so that the machine is more stable than in the deployed configuration of the lifting structure). In this transport mode, the maximum authorized value of the commanded travel speed Vtcmax changes as a function of the measured tilt angle A of the chassis according to a first curve (Figure 3).

[0082] In work mode, the lifting structure 5 is in a deployed configuration (so that the machine is less stable than in the folded configuration of the lifting structure). In this work mode, the maximum authorized value of the commanded travel speed Vwcmax changes as a function of the measured tilt angle A of the chassis according to a second curve (Figure 3) according to which the tilt angle threshold value Awmax for which the authorized speed is zero in said work mode, is lower than the corresponding tilt angle threshold value Atmax defined in transport mode.

[0083] In other words, the value of the tilt angle Awmax for which the value of the maximum authorized commanded speed Vwcmax is zero in the work mode, is less than the value of the tilt angle Atmax for which the value of the maximum authorized commanded speed Vtmax is zero in the transport mode.

[0084] In work mode, the maximum authorized value of the commanded travel speed is zero for the value of the tilt angle Awmax while, in transport mode, for this tilt angle value Awmax, the maximum authorized value of the commanded travel speed Vt1, corresponding to this tilt angle value Awmax, is non-zero. This allows, by switching the machine from transport mode to work mode, preferably move in an area where the chassis tilt angle is less than the Awmax tilt angle value.

[0085] In other words, when in work mode, the chassis has reached the limit tilt angle which prevents the machine from moving on the ground, the machine can return to transport mode by controlling the handling system to switch to the folded configuration, to authorize the movement of the machine and to return to an area of the ground for which the chassis tilt is less than the threshold tilt value defined in work mode in order to be able to return to work mode by controlling the handling system to switch to the deployed configuration.

[0086] Preferably, the machine is equipped with a position sensor (length or angle) making it possible to determine the configuration (the arrangement in space) of the handling system, and possibly of the turret when it is present, and thus the corresponding transport or work mode.

[0087] When the vehicle can no longer be moved on the ground in work mode because the chassis angle has reached the maximum angle Awmax, transport mode can still be activated by folding the lifting structure, to allow the operator to move the machine on less inclined ground.

[0088] Control law

[0089] The control law is detailed below in relation to Figure 3.

[0090] In absolute value and relative to the horizontal, an angular range [0; Awmax] of inclination of the chassis 2 is defined with Awmax a value strictly greater than 0°, preferably between 2° and 6°, for example 5°.

[0091] The maximum authorized value of the commanded speed Vwcmax in work mode to which the movement command of the machine is limited and which is defined by the processing unit 10, decreases, preferably from a given angle AW1, until it preferably reaches a reduced speed value Vw0_reduit (which may correspond to a percentage of the speed VwO which may vary for example between 0% and 20%), then a zero speed when the measured inclination angle A of the chassis 2 reaches the inclination angle threshold value Awmax.

[0092] The decrease in the maximum permitted value of the commanded speed Vwcmax in working mode is preferably carried out according to a constant slope, before reaching the maximum angle value for which the maximum permitted value of the commanded speed is zero. The slope can be expected to be in absolute value between 0.4 and 0.6 km / h per degree.

[0093] In absolute value and relative to the horizontal, an angular range [0; Atmax] of inclination of the chassis 2 is also defined, with Atmax a value strictly greater than Awmax, preferably between 18 and 25°, for example 20°.

[0094] The maximum authorized value for the commanded speed Vtcmax in transport mode to which the movement command of the machine is limited and which is defined by the processing unit 10, decreases, preferably from a given angle At1, until it preferably reaches a reduced speed value VtO_reduit (which may correspond to a percentage of the speed VtO which may vary for example between 0% and 20%), then a zero speed the measured inclination angle A of the chassis 2 reaches the inclination angle threshold value Atmax.

[0095] We can predict that At1 is greater than Aw1 .

[0096] The decrease in the maximum permitted value of the commanded speed Vtcmax is preferably carried out according to a constant slope, up to the maximum angle value Atmax. The slope can be expected to be in absolute value between 3 and 6 km / h per degree.

[0097] The maximum angle value Atmax of said angular range is greater than the maximum angle value Awmax to allow the machine, when it can no longer move on the ground due to its inclination in work mode, to switch from work mode to transport mode by controlling the switch to the folded (or retracted or lowered) configuration of the handling system (in particular the lifting structure) to improve the stability of the machine and thus allow the machine to be moved on the ground to reposition it in an area for which the inclination of the machine returns below the maximum angle value Awmax defined for the work mode.

[0098] Each maximum authorized value of speed Vwcmax and Vtcmax can be stored in a memory of the processing unit 10.

[0099] According to one embodiment, when the operator acts on a control member 11 A of the movement speed, for example a joystick of the control panel 11 of the platform 7, by bringing it into a position corresponding to a given percentage, noted X%, of the movement travel of this speed control member, then the processing unit 10 controls the movement on the ground of the machine at a commanded speed whose value is equal to X% of the maximum authorized value Vwmax or Vtmax (depending on the work or transport mode in which the machine is located).

[0100] Depending on the work or transport mode, from Aw1 or At1, the maximum authorized commanded speed Vwcmax or Vtcmax thus decreases as the angle of inclination increases until it becomes zero when the angle Awmax or Atmax is reached.

[0101] As recalled above, when the tilt angle A of the chassis 2 reaches the maximum value Awmax, so that the machine comes to a standstill, the processing unit 10 is configured to allow the machine to switch from work mode to transport mode in order to allow the machine to be moved. The machine can in particular be moved to an area of the ground for which the tilt angle of the chassis 2 becomes lower than the maximum value Awmax defined for the work mode (see the example of the control law in Figure 3). The operator can then return to work mode.

[0102] Switching to transport mode allows the operator to exit the stopping situation resulting from reaching the maximum tilt angle in work mode. The operator can control the switch to transport or work mode from the platform control panel.

[0103] It can be provided that the control law of the maximum authorized value for the commanded speed as a function of the angle of inclination for the transport mode, includes a level (constant maximum authorized commanded speed value equal to VtO) for the part [0; At1] of the range [0; Atmax], with At1 strictly less than Atmax, At1 being for example equal to 17° and the level speed VtO being for example equal to 5 km / h.

[0104] It can be expected that the control law of the maximum permitted value for the commanded speed as a function of the tilt angle for the working mode, includes a level (constant maximum authorized commanded speed value equal to VwO) for the part [0; Aw1] of the range [0; Awmax], with Aw1 strictly less than Awmax, Aw1 being for example equal to 3° and the level speed VwO being for example equal to 0.7 km / h.

[0105] Additional aspects

[0106] According to one embodiment, the processing unit 10 is configured to modify the maximum authorized value of the commanded speed (in work mode and / or in transport mode) also as a function of the determined value of the steering angle of the wheels (steering angle) so that the operators in the nacelle do not encounter a problem due to a turn that is too tight.

[0107] According to one embodiment, the system for driving the chassis on the ground comprising an electric motor, the processing unit 10 is configured to modify the maximum authorized value of the commanded speed also as a function of the determined value of the temperature of the electric motor. Such consideration of the temperature makes it possible to protect the service life of the electric motor.

[0108] Processing unit

[0109] The processing unit is presented, for example, in the form of a processor and a data memory in which computer instructions executable by said processor are stored, or in the form of a microcontroller.

[0110] In other words, the functions and steps described can be implemented in the form of a computer program or via hardware components (e.g. programmable gate arrays). In particular, the functions and steps performed by the processing unit, in particular for controlling the motorization of the ground movement system and controlling the handling system, can be performed by instruction sets or computer modules implemented in a processor or controller or be performed by dedicated electronic components or components of the programmable logic circuit type (or FPGA which is the acronym for field-programmable gate array, which literally corresponds to in-situ programmable gate array) or of the integrated circuit type specific to an application (or ASIC, which stands for application-specific integrated circuit, is also possible to combine computer parts and electronic parts.

[0111] The processing unit is thus an electronic and / or computer unit. When it is specified that said unit is configured to carry out a given operation, this means that the unit comprises computer instructions and the corresponding execution means which make it possible to carry out said operation and / or that the unit comprises corresponding electronic components.

[0112] Process

[0113] An example of a method for controlling a handling machine as proposed above is presented below in connection with Figure 4.

[0114] In step 410, the operator controls the at least partial deployment (and / or lifting) of the handling system so that the processing unit determines that the machine is in work mode. It can be provided that from a certain level of deployment (and / or height), determined by a position sensor system, for example angular position, of elements of the handling system, the processing unit determines that the machine is in work mode. Similarly, it can be provided that from a certain level of folding (and / or lowering), determined by said position sensor system of element(s) of the handling system and / or of the turret when it is present, the processing unit determines that the machine is in transport mode.

[0115] In step 420, the processing unit 10 measures the angle of inclination of the chassis relative to the horizontal. As explained previously, in said work mode, a maximum authorized value for the commanded travel speed corresponds to the measured angle of inclination. In the case where the machine comprises a member 11 A for manual control of the travel speed, when the speed control member is moved to X% of its available travel stroke, the value of the speed commanded by the processing unit can be defined as being equal to X% of the maximum authorized value for the commanded travel speed (which is defined as a function of the chassis angle).

[0116] In step 430, the processing unit thus controls the movement speed of the machine to a value less than or equal to the maximum authorized value corresponding to the angle of inclination measured according to the instructions received from the speed control member.

[0117] From a given machine tilt angle value, which may be zero, when, in absolute value, the machine tilt angle increases, the maximum authorized value for the commanded speed decreases until it reaches a zero value. The commanded speed decreases according to a given (curve) slope, over a non-zero angular range, for example a range of 0.5°, before reaching the maximum tilt angle value of the machine, so that the speed drop is progressive before reaching the maximum tilt angle of the chassis (for which the maximum authorized commanded speed is zero) which avoids a sudden stop of the machine in the working configuration, which as a reminder is more unstable than the transport configuration, and which therefore limits the risk of tipping and exceeding the maximum tilt angle by inertia.Thus, when in step 440 the tilt angle of the machine has reached a maximum tilt value defined for the work mode, the movement of the machine is prevented in this mode.

[0118] In step 450, the operator commands the withdrawal of the handling system to return to transport mode, for which movement of the machine is permitted for an angular tilt range which includes the maximum tilt value defined for the work mode.

[0119] In step 460, the machine is moved in transport mode into an area for which the tilt angle returns below the maximum tilt value defined for the work mode. In step 470, the operator can then command the deployment of the handling system again to return to work mode.

[0120] It may be provided that the processing unit controls the ground travel system with the commanded speed value being a percentage of the maximum authorized value, said percentage being equal to the percentage of the travel of the ground travel speed control member of the machine.

[0121] The maximum permitted travel speed is thus adapted according to the measured chassis tilt value, to enable a progressive slowing of the machine as the chassis angle increases, particularly in the machine's working configuration, which allows the machine to be slowed down to a safe stop, and thus improve the stability control of the machine.

[0122] This results in a gradual, rather than abrupt, stop of the machine in the working configuration of the machine, which takes into account the progression of the chassis tilt. The gradual reduction of the maximum authorized controlled speed limits the risk of tipping that could result from a sudden stop.

[0123] In other words, the processing unit safely adapts the maximum permissible travel speed when the inclined chassis is close to a limit value, in particular by providing a gradual and not abrupt reduction in the maximum permissible travel speed depending on the chassis tilt angle. The dynamic effects and the elasticity of the structure are reduced, which limits the inertia effect of the machine and thus makes it possible to better respect the tilt limit value when stopping the machine.

[0124] The invention is not limited to the embodiments illustrated in the drawings.

[0125] Furthermore, the term "comprising" does not exclude other elements or steps. Furthermore, features or steps that have been described with reference to one of the embodiments set forth above may also be used in combination with other features or steps of other embodiments set forth above.

Claims

Claims

1. Machine (1) for handling loads or people, comprising: a rolling chassis (2); a motorized drive system (12) for moving the chassis (2) on the ground; a sensor system (19) for inclination of the chassis (2) making it possible to measure an angle (A) of inclination of the chassis (2); - a handling system (4) which is capable of taking different configurations in space relative to the chassis; - a processing unit (10) for controlling the motorized drive system (12) in movement of the chassis on the ground; - a speed control system (11 A), such as a joystick, making it possible to transmit to the processing unit (10) an instruction for the ground movement speed of the machine; - a control system, such as a joystick, of the handling system for controlling its configuration in space; the processing unit (10) being configured to operate the machine in two distinct modes, comprising: - a mode called work mode for which the handling system (4) is in a first spatial configuration called work, for example deployed at height, and - a mode called transport mode for which the handling system (4) is in a second spatial configuration, for example folded or retracted, for which the machine has greater stability than in said working configuration of the handling system (4) of the machine; characterized in that the processing unit (10) is configured to, in working mode, define a maximum authorized value of commanded speed (Vwcmax) for the movement on the ground of the machine which is a function of the measured angle of inclination (A) of the chassis, said maximum authorized value of commanded speed being decreasing when, in absolute value, the angle of inclination (A) increases from a given value of inclination (Aw1), which may be zero, towards a maximum angle value (Awmax) which is greater than said given inclination value (Aw1), the maximum permitted commanded speed value (Vwcmax) being zero for said maximum inclination angle value (Awmax).

2. Machine according to claim 1, in which, in working mode, the curve of the maximum authorized commanded speed value defined as a function of the angle of inclination of the chassis, comprises at least one portion which has a continuous downward slope over a range of positive inclination angle values ([Aw1 - Awmax[).

3. Machine according to claim 2, in which said at least one decreasing portion of the curve of the maximum authorized commanded speed value defined as a function of the angle of inclination of the chassis is a straight line segment.

4. Machine according to any one of the preceding claims, wherein, in working mode, the difference between the value of the maximum tilt angle (Aw ma x) for which the maximum authorized commanded speed value is zero, and the value of the angle of inclination (Aw1) from which the maximum authorized commanded speed value decreases, is at least equal to 0.5°.

5. Machine according to any one of the preceding claims, in which, in working mode, the value of the maximum tilt angle of the chassis (Aw ma x) for which the maximum authorized commanded speed value is zero, is preferably between 1.5° and 6°, for example 5°.

6. Machine according to any one of the preceding claims, in which, in working mode, the maximum value of commanded speed authorized for a chassis tilt angle of 0°, noted VwO, is less than or equal to 0.7 m / s.

7. Machine according to any one of the preceding claims, in which, in working mode, the value of the maximum authorized commanded speed value, denoted Vw0_r, just before reaching the maximum angle Awmax, is between 0.05*Vwo and 0.5*Vwo, with Vwo the maximum authorized commanded speed value in working mode for a chassis tilt angle of 0°.

8. Machine according to any one of the preceding claims, in which the processing unit (10) is configured to, in transport mode, define a maximum authorized value of commanded speed (Vtcmax) for the ground movement of the machine which is non-zero in a given angular range which includes said maximum angle value (Awmax) defined for the work mode.

9. Machine according to any one of the preceding claims, in which the processing unit (10) is configured to, in transport mode, define a maximum authorized value of commanded speed (Vtcmax) for the movement on the ground of the machine which is a function of the measured angle of inclination (A) of the chassis, and which decreases when the angle of inclination (A) increases from a given inclination value (At1), which may be zero, towards a maximum angle value (Atmax).

10. Machine according to claim 9, wherein said maximum angle value (Atmax) in transport mode is greater than the maximum angle value (Awmax) in work mode.

11. Machine according to any one of the preceding claims, in which, in work mode, when the angle (A) of inclination of the chassis (2) reaches the maximum value (Awmax), so that the machine comes to a standstill, the processing unit (10) is configured to allow the machine to switch from work mode to transport mode by control of the handling system, the processing unit being configured to, when the machine is in transport mode, authorize the movement on the ground of the vehicle up to a maximum angle of inclination of the chassis which is greater than the maximum angle of inclination of the chassis defined in work mode, so as to allow the machine to return to an area of the ground for which the angle of the chassis is less than the maximum value (Awmax) of inclination of the chassis (2) defined in work mode.

12. Machine according to any one of the preceding claims, in which the speed control system (11 A) comprising a manual speed control member operable over a given stroke, such as a joystick, the processing unit (10) is configured to, in response to actuation by the driver of said speed control member manual control, controlling the motorized drive system (12) in movement of the chassis on the ground, to move the machine according to a commanded speed value which is less than or equal to said maximum authorized value (Vwcmax) in work mode and which is defined according to the position of the manual control member.

13. Machine according to claim 12, in which, following the movement of the manual control member to control the speed, the processing unit defines the value of the commanded speed by multiplying the maximum authorized value of the commanded speed by the ratio between the stroke traveled by the manual control member and the total available stroke of said manual control member.

14. Machine according to any one of the preceding claims, in which, in work mode, the processing unit (10) is configured to, over the angular range [0; Aw1] of inclination of the chassis, the value Aw1 being less than the maximum angle value Awmax, define the maximum authorized value of commanded speed (Vwcmax) for the ground movement of the machine in work mode, as being equal to a constant value (VwO).

15. Machine according to any one of the preceding claims, in which the handling system (4) carried by the chassis comprises a set of arms (6) articulated together and a platform (7) coupled to said set of arms (6), said set of arms (6) being capable of taking a deployed configuration in height, according to which the work mode is activated, and a folded configuration according to which the transport mode is activated.

16. Machine according to any one of the preceding claims, in which the machine comprises a turret (3) rotatably mounted on the chassis (2) around an axis orthogonal to the ground support plane of the wheels of the machine, the handling system (4) being carried by the turret (3).

17. A method of controlling a machine according to any preceding claim, said method comprising the following steps: - control (410) of the handling system, in the direction of a deployment or output of an element of the handling system, so that the processing unit determines that the machine is in work mode; - from a given chassis tilt angle value, which may be zero, reduction of the maximum authorized value (Vwcmax) for the commanded speed of movement of the machine when, in absolute value, the measured tilt angle (420) of the chassis increases; - control (430) of the machine movement speed to a value less than or equal to the maximum authorized value (Vwcmax); - reaching (440) the maximum tilt angle (Awmax) of the chassis defined for the work mode so that the maximum value authorized for the commanded travel speed is zero; - control (450) of the handling system (4), in the direction of a folding or retraction of an element of the handling system, so that the processing unit determines that the machine is in transport mode; - moving (460) the machine in said transport mode to reach an area for which the measured tilt angle of the chassis falls below the maximum tilt value defined for the work mode; - preferably, control (470) of the handling system to return to work mode.

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