FR3144972A1 - Device for damping pendulum oscillations of the load to be loaded in the hold of an airship dedicated to transporting heavy loads - Google Patents

Abstract

Damping device (100) intended to be integrated into a system (10) for lifting a load (2) by means of a lifting cable (C, C1, C2), said lifting system being intended to equip an airship (1), said device comprising: a guiding device (110, 1101, 1102) of said lifting cable in a predetermined direction, said guiding device forming a firing point (T1, T2), and mechanical suspension means (120) of said guiding device to the airship, said suspension means operating in two directions of a plane perpendicular to said predetermined direction, said suspension plane of the guiding device. Figure for publication: Figure 1

Description

Device for damping pendulum oscillations of the load to be carried in the hold of an airship dedicated to the transport of heavy loads Field of invention

The present invention relates to a passive or active damping device implemented in the load lifting system, used from an airship/dirigible dedicated to the transport of heavy loads and designed to carry out point-to-point transport and carry out the load exchange (loading/unloading or lifting/depositing) in controlled hovering flight. The performance of such a mission by such an apparatus requires securing the load exchange, in particular the loading/lifting which can cause the appearance of oscillations of the load (similar to a pendulum system) whose frequency increases as the lengths of the cables used are reduced (the winding of the cables is carried out via one or more winches).

STATE OF THE ART

Point-to-point cargo transport, in the absence of road, rail or airport infrastructure, is currently only feasible using helicopters (or aircraft whose lift and propulsion are provided by a rotary wing driven by a motorized rotor), whose maximum payload is limited to a few tonnes. The high fuel consumption, low maximum payload and therefore the operational cost of this solution open up an opportunity for aircraft that can offer a greater maximum payload, lower fuel consumption, therefore lower operating costs and a comparable range.

Airships meet these requirements because they are supported by Archimedes' thrust, their maximum payload can be increased to several dozen tons, and they also offer the possibility of loading and unloading in hovering flight. However, the problem of load oscillations must be solved.

• un dispositif de guidage du câble de levage selon une direction prédéterminée, ledit dispositif de guidage formant point de tir, et
• des moyens de suspension mécanique du dispositif de guidage au dirigeable, les moyens de suspension opérant selon deux directions d’un plan perpendiculaire à ladite direction prédéterminée, dit plan de suspension du dispositif de guidage.

According to a first aspect of the invention, there is provided a damping device intended to be integrated into a system for lifting a load by means of a lifting cable, the lifting system being intended to equip an airship, said device comprising:

• a device for guiding the lifting cable in a predetermined direction, said guiding device forming a firing point, and
• mechanical suspension means of the guidance device on the airship, the suspension means operating in two directions of a plane perpendicular to said predetermined direction, called the suspension plane of the guidance device.

According to one possibility, the mechanical suspension means are passive.

Alternatively, mechanical suspension means are active.

Mechanical suspension means can be electromechanical or hydraulic.

According to a second aspect of the invention, a lifting system is proposed integrating a damping device according to the first aspect of the invention.

According to another aspect of the invention, there is provided an airship implementing a lifting system according to the second aspect of the invention.

DESCRIPTION OF FIGURES

• est une vue d’ensemble d’un dirigeable en cours d’opération de levage,
• est une vue latérale du dirigeable représenté sur ,
• est également une vue rapprochée d’un dirigeable en vol stationnaire, pendant le chargement de la grume, avec une solution d’amortissement mise en œuvre
• est une vue schématique isométrique d’une architecture d’un dispositif d’amortissement selon l’invention, avec une charge suspendue,
• est une vue rapprochée d’un dirigeable en vol stationnaire, pendant le chargement d’une grume, avec une solution d’amortissement mise en œuvre,
• est encore une vue rapprochée d’un dirigeable en vol stationnaire, pendant le chargement de la grume, avec une solution d’amortissement mise en œuvre,
• présente deux détails du mécanisme de guidage pour permettre la suspension du point de tir avec des amortisseurs hydrauliques,
• présente une vue de dessus d’une mode de réalisation du dispositif de avec une solution d’amortissement passif,
• présente une vue de dessus d’une mode de réalisation du dispositif de avec une solution d’amortissement actif,
• présente une vue de dessus d’une mode de réalisation du dispositif de avec une autre solution d’amortissement actif,
• présente un schéma-bloc représentant le principe de l’asservissement mis en œuvre dans la solution d’amortissement actif.
• est une vue schématique isométrique d’une architecture d’un dispositif d’amortissement selon l’invention, avec une charge suspendue,
• présente des détails en vue isométrique de dessus, de droite et de gauche, sur l’oscillation du câble passant par le mécanisme d’articulation suspendu.

Other advantages and particularities of the invention will appear on reading the detailed description of implementations and embodiments which are in no way limiting, with regard to the appended drawings in which:

• is an overview of an airship during lifting operation,
• is a side view of the airship shown in ,
• is also a close-up view of a hovering airship, while loading the log, with a damping solution implemented
• is an isometric schematic view of an architecture of a damping device according to the invention, with a suspended load,
• is a close-up view of a hovering airship, while loading a log, with a damping solution implemented,
• is yet another close-up view of a hovering airship, while loading the log, with a damping solution implemented,
• presents two details of the guidance mechanism to allow the suspension of the firing point with hydraulic shock absorbers,
• shows a top view of one embodiment of the device with a passive damping solution,
• shows a top view of one embodiment of the device with an active damping solution,
• shows a top view of one embodiment of the device with another active damping solution,
• presents a block diagram representing the principle of the control implemented in the active damping solution.
• is an isometric schematic view of an architecture of a damping device according to the invention, with a suspended load,
• shows isometric top, right and left view details of the cable swing through the suspended hinge mechanism.

Description of embodiments

The embodiments described below being in no way limiting, it will be possible in particular to consider variants of the invention comprising only a selection of the features described, subsequently isolated from the other features described, if this selection of features is sufficient to confer a technical advantage or to differentiate the invention compared to the state of the prior art. This selection comprises at least one feature, preferably functional without structural details, or with only a part of the structural details if this part alone is sufficient to confer a technical advantage or to differentiate the invention compared to the state of the prior art.

In the figures, an element appearing in several figures retains the same reference.

illustrated is an overall view of an airship 1 in hovering flight, during an operation to lift a load 2 by a lifting system 10, in particular by means of lifting cables C1, C2.

is a side view of the airship shown in , while loading a log 2 as a load.

• une extrémité du câble C1 est fixée au niveau d’un point d’attache A3 de la charge 2, tandis que l’autre extrémité dudit câble passe par un point de tir T1 au niveau d’un treuil (non représenté) fixé dans une soute S du dirigeable 1.
• une extrémité du câble C2 est fixée au niveau d’un point d’attache 3 de la charge 2, tandis que l’autre extrémité dudit câble passe par un point de tir T2 au niveau d’un treuil (non représenté) fixé dans la soute S du dirigeable 1.

According to the prior art:

• one end of the cable C1 is fixed at an attachment point A3 of the load 2, while the other end of said cable passes through a firing point T1 at a winch (not shown) fixed in a hold S of the airship 1.
• one end of the cable C2 is fixed at an attachment point 3 of the load 2, while the other end of said cable passes through a firing point T2 at a winch (not shown) fixed in the hold S of the airship 1.

illustrates on its left part a close-up view of an airship 1 equipped with a lifting system 10 integrating a device 100 according to the invention, during the loading of a load 2.

The airship has a longitudinal direction, also called the roll axis, according to a vector i, a transverse direction, also called the pitch axis, according to a vector j and a yaw direction according to a vector k.

As in the prior art, in the example shown, the log carrying load 2 is lifted by two cables C1, respectively C2. The two cables C1, respectively C2, are wound by, and unwound from, two winches, Tr1, respectively Tr2.

Winches Tr1 and Tr2 are not located in hold S. However, they could be located there.

The device 100 comprises two guiding devices 1101 and 1102 for each of the lifting cables in a predetermined direction. The two devices 110 are better visible in other figures.

In the example shown, the predetermined direction of each of the two guidance devices is the yaw direction. Other directions are possible and the two directions are not necessarily parallel.

As will be better understood hereinafter, each of the devices 100 comprises means for mechanically suspending the guidance device 100 from the airship, the suspension means operating in two directions of a plane perpendicular to said predetermined direction, called the suspension plane of the guidance device.

In the example shown, each of the predetermined directions being the yaw direction, the suspension plane of each of the guide devices 1101 and 1102 is a plane formed by the longitudinal direction and the pitch direction. Other planes are possible.

The distance, in the predetermined direction, between a winch and an associated guidance device is called the firing distance associated with the guidance device. In the example shown, the firing distance associated with the guidance device 1101 on the one hand, and the firing distance associated with the guidance device 1102 on the other hand, are equal. Consequently, the suspension plane of the guidance device 1101 coincides with the suspension plane of the guidance device 1102. This is not necessarily the case.

The mechanical suspension means are arranged so that the associated guide device is only capable of movement according to the suspension plane of the guide device.

More generally, the connection between the guide device 110 and the associated mechanical suspension means has two degrees of freedom formed by the two translations in the suspension plane of the guide device.

Also, the firing points T1 and T2 can move in the plane formed by the vectors i and j shown in the figure. Subsequently, the angle of a firing point with respect to the vector i is denoted θ, while the angle of a firing point with respect to the vector j is denoted φ.

illustrates an architecture of a damping device 100 intended to be integrated into the load lifting system 2.

• un dispositif de guidage 110 du câble de levage, et
• des moyens de suspension mécanique 120 du dispositif de guidage au dirigeable, les moyens de suspension autorisant un déplacement du dispositif de guidage dans un plan prédéterminé.

The device 100 comprises:

• a lifting cable guiding device 110, and
• mechanical suspension means 120 of the guidance device to the airship, the suspension means allowing movement of the guidance device in a predetermined plane.

More precisely and as illustrated in the figure, the mechanical suspension means 120 are formed of four mechanical cylinders vX, vXz, vY, vYz forming shock absorbers.

Each of the mechanical cylinders vX, respectively vY, is connected at one end by a ball joint to the airship and is connected at another end by a ball joint to the guide device 110.

Each of the mechanical cylinders vXz and vYz is connected at one end by a ball joint to the airship and connected at another end by a ball joint to a mechanical cylinder vX, respectively vY. The cylinders vXz, respectively vYz, allow a movement of the guidance device along the plane formed by the vectors i and k, respectively along the plane formed by the vectors j and k.

More precisely, the cylinder vX allows a movement of the guide device 110 in the direction i, i.e. the longitudinal direction, while the cylinder vY allows a movement in the guide device 110 in the vector j, i.e. the transverse direction. The guide device 110 can thus be moved in the plane formed by the vectors i and k.

• illustre un déplacement de la grume 2 vers la proue du dirigeable 1. Les points de tirs T1 et T2 sont alors déplacés selon le vecteur i vers la proue du dirigeable.
• illustre un déplacement de la grume 2 vers la poupe du dirigeable 1. Les points de tirs T1 et T2 sont alors déplacés selon le vecteur i vers la poupe du dirigeable.

Thus, the damping device dissipates the oscillations: there is possible transmission of a speed-force (i.e. of a mechanical power) linked to the oscillation of the load suspended from the cable to the mechanical suspension dissipating the energy of this oscillation, as illustrated by And :

• illustrates a movement of log 2 towards the bow of airship 1. The firing points T1 and T2 are then moved according to vector i towards the bow of the airship.
• illustrates a movement of log 2 towards the stern of airship 1. The firing points T1 and T2 are then moved according to vector i towards the stern of the airship.

illustrates details of the guidance mechanism required to enable suspension of the firing point.

The left part of provides in an upper area a side view in section of the guiding mechanism 110 of the cable C with a cutaway along a plane formed by the vectors i and k. A lower area of the left part of the provides a top view in section of the guide mechanism 110 along a plane formed by the vectors i and j.

The guiding mechanism 110 of the cable C is a sliding connection of direction k, formed by rollers.

The right part of provides a side view of the mechanical jacks v1 and v2 previously described, in a plane formed by the vectors i and k.

presents a top view of a hydraulic diagram of the embodiment of the suspension means 120 of the guide device 100 of the .

• d’un vérin hydraulique pour l’amortissement selon la direction X, formée par le vecteur i, dont une partie, corps ou tige de vérin, est fixée sur le dispositif de guidage 100 et l’autre partie est liaisonnée au dirigeable au moyen d’une rotule.
• d’un vérin hydraulique pour l’amortissement selon la direction Y dont une partie, corps ou tige de vérin, est fixée sur le dispositif de guidage 110 et l’autre partie est liaisonné au dirigeable au moyen d’une rotule.

The 120 mechanical suspension means are formed:

• of a hydraulic cylinder for damping in the direction X, formed by the vector i, one part of which, cylinder body or rod, is fixed to the guide device 100 and the other part is connected to the airship by means of a ball joint.
• of a hydraulic cylinder for damping in the Y direction, one part of which, cylinder body or rod, is fixed to the guide device 110 and the other part is connected to the airship by means of a ball joint.

The figure illustrates that each of the two cylinders is equivalent to a suspension formed by a spring and a shock absorber arranged in parallel.

shows a top view of a hydraulic embodiment of the device with an active damping solution,

The guiding device 100 forming a firing point is mechanically suspended and controlled in position by two hydraulic cylinder actuators vX and vY, for positioning along the Y axis, respectively the X axis.

• un distributeur 4/2 d’activation passif-actifs 130 présentant quatre orifices, dont deux orifices sont dits orifice d’entrée et orifice de sortie, chacun des deux orifices de sortie étant fluidiquement raccordé à une chambre respective du vérin vY, le distributeur présentant une position de repos et une position de travail ;
• un distributeur 4/3 d’activation de puissance contrôlé 140 pour commander le vérin vY, présentant quatre orifices, dont deux orifices sont dits orifice d’entrée et orifice de sortie, chacun des deux orifices de sortie étant fluidiquement raccordé aux orifices d’entrée du distributeur 130, le distributeur présentant une position de repos et deux positions de travail ;
• un circuit d’alimentation en haute pression raccordé à l’un des orifices d’entrée du distributeur 140, et un circuit de retour en basse pression raccordé à l’autre des orifices d’entrée du distributeur 140.

The suspension device further comprises:

• a 4/2 passive-active activation distributor 130 having four ports, two of which are called the inlet port and the outlet port, each of the two outlet ports being fluidically connected to a respective chamber of the cylinder vY, the distributor having a rest position and a working position;
• a 4/3 controlled power activation distributor 140 for controlling the cylinder vY, having four ports, two of which are called the inlet port and the outlet port, each of the two outlet ports being fluidically connected to the inlet ports of the distributor 130, the distributor having a rest position and two working positions;
• a high pressure supply circuit connected to one of the inlet ports of the distributor 140, and a low pressure return circuit connected to the other of the inlet ports of the distributor 140.

In the stable, rest position of the distributor 130, the two outlet ports communicate, the two chambers of the cylinder vY then being directly connected. In the working position of the distributor 130, each of the outlet ports is connected to a respective inlet port. The selection of the position of the distributor 130 is controlled by control signals S.

In the stable, rest position, all ports are closed. In a first working position, a first inlet port is connected to a first outlet port and a second inlet port is connected to a second outlet port. In a second working position, the first inlet port is connected to the second outlet port and the second inlet port is connected to the first outlet port. The selection of the position of the distributor 130 is controlled by control signals S.

Similarly, the suspension device further comprises a 4/2 passive-active activation distributor of the vX cylinder, a 4/3 controlled power activation distributor for controlling said cylinder and is connected to a high pressure supply and low pressure return circuit.

shows a top view of an electromechanical embodiment of a damping device according to the invention,

Two mechanical actuators, AX, and Ay, with rods are controlled by control signals Sx, Sy, to position the 110 firing point guidance device with transmission of forces-speeds so as to actively dissipate the oscillations of the suspended load.

is a block diagram describing the operating principle of a possible servo logic implemented in the active damping solution, valid for both hydraulic and electromechanical actuators.

The position control of each of the actuators is achieved by measuring their respective rod position via LVDT ( Linear Variable Differential Transformer ) type sensors.

• quand l’angle θ (en valeur absolue) dépasse une valeur seuil (supérieur ou égale à θseuil) ET que sa dérivée première (vitesse angulaire dθ/dt) est inférieure (en valeur absolue) à une valeur seuil Ωseuil, l’actionneur X se déploie (ou se rétracte) d’une certaine portion de sa course totale selon une consigne (commande) proportionnelle la valeur (signée, positive ou négative) de θ mesurée en radians, transmettant ainsi l’effort-vitesse nécessaire à la dissipation de l’oscillation de la charge suspendue.
• quand l’angle φ (en valeur absolue) dépasse une valeur seuil (supérieur ou égale à φseuil) ET que sa dérivée première (vitesse angulaire dφ/dt) est inférieure (en valeur absolue) à une valeur seuil Ωseuil, l’actionneur Y se déploie (ou se rétracte) d’une certaine portion de sa course totale selon une consigne (commande) proportionnelle la valeur (signée, positive ou négative) de φ mesurée en radians, transmettant ainsi l’effort-vitesse nécessaire à la dissipation de l’oscillation de la charge suspendue.

The device according to the invention comprises angle sensors integrated in the articulation mechanism for the suspension of the firing point, to measure the angle of the cable at the firing point θ and φ:

• when the angle θ (in absolute value) exceeds a threshold value (greater than or equal to θthreshold) AND its first derivative (angular speed dθ/dt) is less (in absolute value) than a threshold value Ωthreshold, the actuator X extends (or retracts) by a certain portion of its total travel according to a setpoint (command) proportional to the value (signed, positive or negative) of θ measured in radians, thus transmitting the force-speed necessary to dissipate the oscillation of the suspended load.
• when the angle φ (in absolute value) exceeds a threshold value (greater than or equal to φthreshold) AND its first derivative (angular speed dφ/dt) is less (in absolute value) than a threshold value Ωthreshold, the actuator Y extends (or retracts) by a certain portion of its total travel according to a setpoint (command) proportional to the value (signed, positive or negative) of φ measured in radians, thus transmitting the force-speed necessary to dissipate the oscillation of the suspended load.

The combination of the actions of the two actuators Ax and Ay on the suspended firing point 110 therefore allows the dissipation of load oscillations regardless of the direction (in the XY plane) in which it oscillates.

Of course, the same control logic could be implemented for an active solution of a hydraulic nature as shown in .

provides different views of the architecture of the damping device as proposed in the present invention with the suspended load. The damping springs are schematic representations equivalent to the actuators implemented to achieve the damping.

The suspended articulation mechanism integrates the sensors (sensor device) necessary for measuring the angles θ and φ. In accordance with the servo logic shown in figure , these measurements are necessary for position control of the X and Y actuator rods.

illustrates a sequence of steps implementing active damping of load oscillations applied to a single actuator X acting on the positioning of the suspended articulation mechanism.

The figures schematically represent the successive steps (1 to 7) implementing active damping with a single actuator (the one acting along the X axis) but the principle is exactly the same for the Y axis and for the combination of the 2 X and Y axes combined.

The extension and retraction movements of the actuator rod according to the servo logic (detailed below) allowing active damping of load oscillations.

At step 1, the angle θ 1 is above the threshold value θthreshold and when the speed dθ/dt is below the threshold Ωthreshold, which causes the actuator rod to extend proportionally to the value of the angle θ 1 at step 2.

At step 3, the angle θ 2 is above the threshold value θthreshold and when the speed dθ/dt is below the threshold Ωthreshold, which causes the actuator rod to retract proportionally to the value of the angle θ 2 (because it has a sign opposite to θ1) at step 4.

Step 5 is in principle equivalent to step 1, but with a value of the angle θ3 lower than θ1 (the oscillation energy of the load having been partly dissipated during the previous steps by the transmission of the force-velocity to the suspended articulation point), the extension of the actuator rod is therefore less significant than in step 2.

At step 6, the load has completely calmed down as the oscillation energy has completely dissipated, and the actuator retracts one last time at step 7 to return to an equilibrium position.

Of course, the invention is not limited to the examples which have just been described and numerous arrangements can be made to these examples without departing from the scope of the invention. In addition, the various characteristics, forms, variants and embodiments of the invention can be associated with each other in various combinations to the extent that they are not incompatible or exclusive of each other.

Claims (6)

Damping device (100) intended to be integrated into a system (10) for lifting a load (2) by means of a lifting cable (C, C1, C2), said lifting system being intended to equip an airship (1), said device comprising:

• a guiding device (110, 1101, 1102) for said lifting cable in a predetermined direction, said guiding device forming a firing point (T1, T2), and
• mechanical suspension means (120) of said guidance device on the airship, said suspension means operating in two directions of a plane perpendicular to said predetermined direction, called the suspension plane of the guidance device.

Device according to the preceding claim, in which the mechanical suspension means are passive. Device according to the preceding claim, in which the mechanical suspension means are active. Device according to any one of the preceding claims, in which the mechanical suspension means are of the electromechanical or hydraulic type. Lifting system (S) incorporating a damping device according to any one of the preceding claims. Airship (1) implementing a lifting system (10) according to the preceding claim.