Load compensation device and exoskeleton

Abstract

load compensation device, in particular for gravitational loads, applicable to exoskeletons. The present invention relates to a load compensation device (201, 301, 501, 601, 701, 901) comprising: an assisted joint (3; 302) configured to be constrained to a support structure (102, 104; 303; 702, 704); a main rod (304) comprising a proximal end (305) connected to the assisted joint (3; 302), and additionally comprising a distal end (306) configured to be stressed by an applied load (11); an auxiliary rod (307) comprising a first end (308) and a second end (309), the first end (308) being articulated on the main rod (304) for rotation of said auxiliary rod (307) with respect to the main rod (304), the second end (309) being movable on a plane on which the applied load (11) rests;an elastic element (310, 910) configured to provide an elastic force acting between the second end (309) of the auxiliary rod (307) and the distal end (306) of the main rod (304); a regulating system (313; 613) configured to modify a distance between the second end (309) of the auxiliary rod (307) and the assisted joint (3; 302), so as to vary a preload of the elastic element (310, 910). The elastic element (310, 910) is configured to provide the elastic force based on a kinematic configuration of the load compensation device (201, 301, 501, 601, 701, 901), so as to compensate for the applied load (11) on a component thereof that is transverse to the main rod (304). The present invention further relates to an exoskeleton (100; 700) comprising at least one load compensation device (201, 301, 501, 601, 701, 901).

Description

1 / 27 LOAD COMPENSATION DEVICE AND EXOSKELETON DESCRIPTION Field of application

[0001] The present invention relates to a load compensation device, in particular for compensating gravitational loads. In a preferred and non-limiting application, the present invention also relates to a related exoskeleton.

[0002] In general, the present invention finds non-limiting applications in the field of manipulation devices and in the field of physical activity and rehabilitation exercise devices. State of the art

[0003] In recent years, exoskeletons have found various applications that are primarily related to the biomedical and industrial fields.

[0004] In the biomedical field, exoskeletons are designed to enhance individuals' physique and motor skills, additionally compensating for the effect of gravity, consequently reducing physical exertion and individual effort. In particular, in the biomedical field, exoskeletons are used in the field of motor function recovery and assistance. Recovery refers to the rehabilitation of a patient, while assistance refers to the simple case of aiding, where a user's motor skills are irreversibly compromised.

[0005] In the industrial field, exoskeletons are primarily used in the manufacturing and construction industries, where operators have to maintain Petition 870250015083, dated 25 / 02 / 2025, page 33 / 77 2 / 27 uncomfortable postures or having to move or lift heavy loads; additionally, exoskeletons are also used as aids for healthcare workers. In general, in this industrial field, the exoskeleton is designed to relieve strain on one or more parts of the body.

[0006] In exoskeletons, load compensation is achieved through different technologies that can be categorized as passive or active: passive compensation technology uses a set of one or more elastic elements, which are loaded during movement and release deformation energy during movement in the opposite direction; instead, active compensation technology uses a motor-driven traction, typically of the electric type; other types of traction can provide piezoelectric actuators, SMAs (Shape-Memory Alloys), pneumatic traction, or electroactive polymers.

[0007] Passive compensation technology has the advantage of not requiring an external power supply, making it possible to obtain lighter, more compact exoskeletons that are also free from electronic power supply. Undoubtedly, passive compensation systems usually consist of kinematic chains of elastic elements that support the user's weight through deformation.

[0008] However, exoskeletons with passive compensation cannot apply full compensation to loads, for any position taken by the user, but they do have Petition 870250015083, dated 25 / 02 / 2025, page 34 / 77 3 / 27 only a point of equilibrium (balance). Additionally, during the loading motion, the user has to produce force in such a way as to load the elastic elements.

[0009] Instead, active compensation technology requires an external power supply, electronics, and control logic. Disadvantageously, electric traction motors are bulky, resulting in a heavier and less ergonomic exoskeleton than a passive one. Additionally, in cases of high energy consumption, the exoskeleton cannot be efficiently powered by a lightweight and compact battery system.

[0010] For these reasons, the most widespread exoskeletons are of the passive compensation type, both in the industrial and biomedical fields.

[0011] Examples of exoskeleton systems and active type gravitational load compensation devices are provided in Korean patent application number KR 2016 / 0071661, European patent application number EP 3,278,938 A1, and international patent applications numbers WO 2017 / 161257 and WO 2015 / 106278, which describe solutions including actuators.

[0012] Examples of exoskeleton systems and passive type gravitational load compensation devices are provided in Korean patent application number KR 2012 / 0082221, international patent application number WO 2015 / 147584, Canadian patent number CA 2,952,403, US patent application number US 2012 / 0184880, Canadian patent number CA Petition 870250015083, dated 25 / 02 / 2025, page 35 / 77 4 / 27 2,544,645, international patent application number WO 2018 / 165399 A1, and European patent number EP 2,861,387, which include elastic elements, also of the adjustable type, proposed in exoskeletons and in devices that are usable by a user.

[0013] A further example of a gravitational load compensation device is provided in European patent application number EP 3,342,390 A1, which refers to an apparatus for supporting a limb comprising passive force elements connected to a wearable element and active support elements actuated by motor-driven cable traction actuators. However, the device known from European patent application number EP 3,342,390 A1, although embodying a hybrid structure between active and passive systems, also has disadvantages and limitations of application.

[0014] Document CA2544645A refers to a passive gravity balancing device that combines the use of auxiliary parallelograms with springs.

[0015] Document US2015231018A1 refers to a walking assistance device including at least one joint that corresponds to at least one joint of a user, at least one link that connects the joint and is rotated in response to the rotation of the joint, a spring that is mounted on the link or joint so that a length of the spring is changed according to the rotation of the link or joint, and a processor that controls the change in the length of the spring to compensate for weight from gravity when the user walks. Petition 870250015083, dated 25 / 02 / 2025, p. 36 / 77 5 / 27

[0016] Document WO2018213363A1 refers to an armor configured to be used by a user, an arm support attached to the armor to support and follow the movement of a user's arm; and compensation elements attached to the arm support to apply a displacement force to the arm support to compensate for a gravitational force acting at least partially on the arm.

[0017] Document TW201226010A refers to a lower limb strength augmentation device comprising a first fastening element, a first connecting assembly, a second connecting assembly, a first elastic element and a second elastic element. Summary of the invention

[0018] The objective of the present invention is to solve the disadvantages of the prior art.

[0019] The additional particular objective of the present invention is to provide a device that has reduced energy consumption and can, consequently, be efficiently supplied with energy also by a portable battery system.

[0020] The additional particular objective of the present invention is to enable variable load compensation, in particular gravitational loads, for any position taken by the user.

[0021] The additional particular objective of the present invention is to provide a device that is less bulky than fully active ones, in order to obtain lighter and more ergonomic exoskeletons.

[0022] These and other objectives of the present Petition 870250015083, dated 25 / 02 / 2025, page 37 / 77 6 / 27 inventions are achieved by a load compensation device and a related exoskeleton in accordance with the features of the appended patent claims, which form an integral part of the present description.

[0023] An underlying idea of ​​the present invention is to provide a load compensation device comprising: - an assisted joint configured to be confined to a support structure; - a main rod comprising a proximal end connected to the assisted joint, and additionally comprising a distal end configured to be tensioned by an applied load; - an auxiliary rod comprising a first end and a second end, the first end being articulated on the main rod for rotation of the auxiliary rod with respect to the main rod, and the second end being movable on a plane on which said applied load rests; - an elastic element configured to provide an elastic force acting between the second end of the auxiliary rod and the distal end of the main rod; - an adjustment system configured to modify the distance between the second end of the auxiliary rod and the assisted joint, in such a way as to vary the preload of the elastic element; where the elastic element is configured to provide elastic force based on a kinematic configuration of the load compensation device, in such a way as to compensate for the load applied to a component thereof which is Petition 870250015083, dated 25 / 02 / 2025, page 38 / 77 7 / 27 transversal to said main rod.

[0024] In summary, the load compensation device in accordance with the present invention is designed for the purpose of completely identifying and compensating, with minimal energy consumption and bulk, the effect of a force, for example, a gravitational force, acting on a main rod that represents the point of attachment of the load compensation device to a structure of a system in which it is inserted, for example, an exoskeleton or a robotic arm.

[0025] The load compensation device of the present invention, therefore, comprises a mechanical structure provided with suitable sensors and control logic, in which a pre-loaded elastic element provides the necessary compensation force.

[0026] Advantageously, the present invention makes possible the realization of a load compensation device that implements a hybrid technology, designed to apply load compensation that adapts to the user's movements, while ensuring high compactness and low energy consumption.

[0027] In particular, the load compensation device in accordance with the present invention makes it possible to merge the positive aspects of passive and active technologies within a single device that can be scalable to any type of appliance or exoskeleton.

[0028] The load compensation device in accordance with the present invention can also advantageously be used in different fields, such as Petition 870250015083, dated 25 / 02 / 2025, page 39 / 77 8 / 27 such as, for example, in industrial robotics, in lifting or handling systems, to develop more compact and energy-efficient devices.

[0029] Preferably, the load compensation device comprises a movable regulating element, associated with the support structure. In particular, preferably, the movable regulating element provides a regulating rod and linear actuator system, or a cable and pulley system driven by a motor.

[0030] Preferably, the elastic element is at least indirectly connected to the second end of the auxiliary rod. In particular, preferably, the load compensation device comprises a compensation cable connecting the second end of the auxiliary rod to the elastic element, with a pulley in close proximity to the distal end of the main rod.

[0031] The load compensation device, which is the object of the present invention, could be applied to one or more joints of an exoskeleton or a robotic arm, making the solution applicable to multiple degrees of freedom.

[0032] An additional idea underlying the present invention is, consequently, to provide an exoskeleton comprising one or more load compensation devices.

[0033] Additional features and advantages of the present invention will become more apparent from the detailed description given hereafter of preferred, but not limiting, embodiments of the present invention. Petition 870250015083, dated 25 / 02 / 2025, page 40 / 77 9 / 27 invention and from the dependent patent claims, which are outlined preferred and particularly advantageous embodiments of the present invention. Brief description of the drawings

[0034] The present invention is illustrated with reference to the following figures, provided by way of non-limiting examples, in which: Figure 1 illustrates an example of an upper limb holding an object subjected to a load induced by gravitational force; Figure 2 illustrates an exoskeleton engaging an upper limb and comprising a load compensation device in accordance with the present invention; Figure 3 illustrates a first embodiment of a load compensation device in accordance with the present invention; Figure 4a and Figure 4b illustrate exemplary performances of a load compensation device in accordance with the present invention; Figure 5 illustrates a second embodiment of a load compensation device in accordance with the present invention; Figure 6 illustrates a third embodiment of a load compensation device in accordance with the present invention; Figure 7 illustrates an exoskeleton encompassing the pelvis and lumbar spine and comprising a load compensation device in accordance with the present invention; Petition 870250015083, dated 25 / 02 / 2025, page 41 / 77 10 / 27 Figure 8 illustrates a fourth embodiment of a load compensation device in accordance with the present invention; Figure 9 illustrates a fifth embodiment of a load compensation device in accordance with the present invention;

[0035] In the different Figures, similar elements will be identified by similar reference numbers. Detailed description

[0036] In preferred embodiments, the load compensation device in accordance with the present invention is used to compensate for the effect of gravitational loads on exoskeletons or robotic arms. In particular, the present invention pertains to exoskeletons applicable to multiple joints of the human body, such as the shoulder, hip, lumbar spine, knee, and to robotic arms. The present invention will refer to this non-limiting application of the load compensation device in accordance with the present invention.

[0037] In this example application, most of the effort required to perform a movement with the upper limbs is used to overcome the gravitational effect, which can be identified as a torque acting on the arm itself. Accordingly, the shoulder is the joint that is primarily stressed. Exoskeletons are devices designed precisely to alleviate the effort of the user, multiplying strength capabilities. In Petition 870250015083, dated 25 / 02 / 2025, page 42 / 77 11 / 27 In particular, the load compensation device in accordance with the present invention is designed to be integrated inside exoskeletons, for upper limbs or also lower limbs, at a user's joint. Similar applications can be implemented, by extension, for robotic arms.

[0038] Figure 1 illustrates an example of an upper limb (1) holding an object (11) subjected to a load induced by gravitational acceleration “g.

[0039] The load “g” acting on the object (11) becomes particularly relevant for the flexion-extension movement of the shoulder of the limb (1): this is the case of the “pick & place” movement that is performed in many industrial fields, such as those in large retail logistics and manufacturing.

[0040] Member (1) can be schematically represented as being composed of rigid bodies (6) and (8), load (11) and masses (7), (9), (10) and (11), respectively. Rods (6) and (8) are connected to each other by a hinge (joint) (5) and confined (compelled) to the ground by means of a hinge (3). This system represents the user's scheme in the vertical plane. Consequently, the compensating torque applied to body (6), which is necessary to compensate for the gravitational effect acting on the system and which is caused by the gravitational acceleration “g”, will be a function of its position taken in the plane, identified by the angles (2) and (4), by the geometric values ​​of rods (6) and (8) and by the corresponding masses (7), (9), (10) and (11). The gravitational effect can, therefore, be understood as Petition 870250015083, dated 25 / 02 / 2025, page 43 / 77 12 / 27 a resultant torque on the rod (6) caused by the weight forces acting on the centroids of the bodies (7), (9), (10) and (11).

[0041] Figure 2 illustrates an exoskeleton (100) engaging the upper limb (1) and comprising a load compensation device (201) in accordance with the present invention.

[0042] As already described, a non-limiting example of application of the present invention is the compensation of gravitational loads acting on the lower limbs during shoulder flexion-extension movement, which is the rotation movement of the shoulder in the vertical plane, as already illustrated in Figure 1, where the arrow (2) represents the shoulder rotation and “go the gravity vector. In this case, the exoskeleton (100) is configured to compensate for the gravitational loads to which the user's shoulder is subjected.

[0043] The application of the load compensation device (201) to the exoskeleton (100) is exemplified to provide a hybrid technology in the case of exoskeletons for upper limbs and for “pick & place” activities.

[0044] The load compensation device (201) is connected to a support structure (102) on which the forces are released. The compensation force is transferred from the device (201) to the limb via an armrest (103) during the flexion-extension movement of the shoulder that is imposed by the user around the hinge (3). The belt (104) preferably contains the electronic components and power supply batteries for all parts. Petition 870250015083, dated 25 / 02 / 2025, page 44 / 77 13 / 27 active, while the strip (105) contains a sensor for detecting the relative rotation between the arm and forearm.

[0045] In general, the load compensation device is associated, in the exoskeleton (100), with a battery to supply energy to the regulation system, which will be described further, with a plurality of sensors and with at least one processor.

[0046] In other embodiments, the load compensation device could be applied to a robot or to a lifting apparatus or to a load handling apparatus, with an assisted joint configured to be confined to a support structure, where there is a main rod, for the purpose of compensating for a transverse component of a load applied to the main rod.

[0047] Figure 3 illustrates a first embodiment of a load compensation device (301) in accordance with the present invention.

[0048] The load compensation device (301), which is in particular configured to compensate for gravitational loads, comprises an assisted joint (302), which is configured to be confined to a support structure (303).

[0049] The load compensation device (301) further comprises a main rod (304) comprising a proximal end (305) connected to the assisted joint (302), and further comprising a distal end (306) configured to be tensioned by the applied load, for example, the load already described (11). Petition 870250015083, dated 25 / 02 / 2025, page 45 / 77 14 / 27

[0050] The load compensation device (301) further comprises an auxiliary rod (307) comprising a first end (308) and a second end (309). The first end (308) is articulated on the main rod (304) for rotation of the auxiliary rod (307) with respect to the main rod (304). The second end (309) is instead movable on a plane on which the applied load (11) rests, and on which the load compensation device (301) is configured to compensate.

[0051] In particular, the auxiliary rod (307) projects outward from the main rod (304) in a direction opposite to the prevailing direction of the applied load (11). In particular, in the exemplary configuration of Figure 3, the main rod (304) is horizontal and the auxiliary rod (307) projects outward from the main rod (304) in an essentially vertical and “upward” direction, consequently on the opposite side of the prevailing direction of the applied load (11) which is “downward”.

[0052] Preferably, the first end (308) of the auxiliary rod (307) is articulated on the main rod (304) in an intermediate position between the proximal end (305) and the distal end (306) of the main rod (304).

[0053] In particular, exactly the distal end (306) of the main rod (304) corresponds to a clamp of a movable structural element subjected to variable loads, such as the already described element (103).

[0054] In general, the length of the rods (304) and Petition 870250015083, dated 25 / 02 / 2025, page 46 / 77 15 / 27 (307), the distances between the constraints and the overall kinematic configuration of the load compensation device are determined based on the desired compensation performance and the energy and volume constraints of the overall system.

[0055] The load compensation device (301) further comprises an elastic element (310), which is configured to provide an elastic force acting between the second end (309) of the auxiliary rod (307) and the distal end (306) of the main rod (304).

[0056] In a preferred embodiment, the elastic element (310) comprises a helical tension or compression spring. In a variation, the elastic element could be a strip made of rubber or of an elastic material that is suitable for the purpose.

[0057] Preferably, the elastic element (310) is at least indirectly connected to the second end (309) of the auxiliary rod (307).

[0058] In a preferred embodiment, such as that shown in Figure 3, the elastic element (310) is indirectly connected to the second end (309) of the auxiliary rod (307), in particular, by providing a compensating cable (311) that directly connects the second end (309) of the auxiliary rod (307) to the elastic element (310).

[0059] Preferably, the elastic element (310) develops axially and is essentially parallel to the main rod (304); as a consequence, the load compensation device can be more compact and it is possible Petition 870250015083, dated 25 / 02 / 2025, page 47 / 77 16 / 27 insert an elastic element with higher hardness. The load compensation device (301) further comprises a pulley (312) in close proximity to the distal end (306) of the main rod (304), wherein the compensation cable (311) engages the pulley (312).

[0060] In one variation, the elastic element (310) can be directly connected to the second end (309) of the auxiliary rod (307), by connecting directly from the distal end (306) to the second end (309) being imposed between them, without the need for a compensating cable, as will be described with reference to Figure 9.

[0061] The load compensation device (301) further comprises a regulating system (313) configured to modify a distance between the second end (309) of the auxiliary rod (307) and the assisted joint (302), in such a way as to vary a preload of the elastic element (310).

[0062] The elastic element (310) is configured to provide an elastic force based on a kinematic configuration taken by the load compensation device (301), in such a way as to compensate for the load applied (11) on a component thereof that is transverse to the main rod.

[0063] In this sense, the adjustment system (313) is preferably configured to minimize a difference between the transverse component of the load (11) to be compensated, and the opposite transverse component provided by the elastic force of the elastic element (310). Petition 870250015083, dated 25 / 02 / 2025, page 48 / 77 17 / 27

[0064] The operating principle performed by the load compensation device (301) is as follows: in any position taken by the user (exoskeleton or robotic arm), appropriate control logics, by means of sensors and processors, process the torque / gravitational force acting on the assisted joint (302). They process the control action to be sent to the regulation system (313) in such a way that the latter will modify the pre-loading of the elastic element (310) through the articulated system of the arms (304) and (307), in such a way that the compensation force becomes equal to that of the gravitational effect.

[0065] In particular, the load compensation device (301) further comprises a plurality of sensors (not shown) configured to measure an absolute position of the main rod (304) and further to measure or obtain a torque that tensions the assisted joint (302) as a result of the applied load (11). Additionally, the load compensation device (301) further comprises at least one processor (not shown) operatively connected to the plurality of sensors and to the regulating system (313), such processor being configured to calculate the preload of the elastic element (310) in such a way as to counterbalance the torque that tensions the assisted joint.

[0066] Preferably, the aforementioned processor is additionally configured to modulate the elastic force provided by the elastic element (310) as a function of a dynamic trajectory that is Petition 870250015083, dated 25 / 02 / 2025, page 49 / 77 18 / 27 measured by multiple sensors, in such a way as to support a movement that is desired by the exoskeleton user or required by the robot's programming.

[0067] An example is provided of a regulation process that can be performed in any position taken by the user in the vertical plane, such as that implemented by the control logics and sensors to manage the duty cycles of the load compensation device (301).

[0068] A single exemplary work cycle can be summarized by the following operational flow: Sensors provide position measurements and send them to the control logic. - The control logics calculate the position taken by the user and the corresponding gravitational action acting on it, expressed as a torque with respect to the reference assisted junction (302). In addition, preferably, the control system processes the movement dynamics and the type of trajectory performed. - A processor calculates a deformation that has to be applied to the elastic element (310) in such a way as to obtain a torque that counterbalances the gravitational action. - A processor processes the control action to be sent to the regulating system (313) which enables the desired deformation of the elastic element (310) to be obtained by solving the kinematics of the articulated system consisting of the rods (304) and (307).

[0069] Preferably, such control is designed to modulate the actuation force as a function of the trajectory and dynamics imposed by the user while performing a Petition 870250015083, dated 25 / 02 / 2025, page 50 / 77 19 / 27 activity, in such a way as to support the user's intention in an application for an exoskeleton (100).

[0070] As already described, the adjustment system (313) is configured to modify a distance between the second end (309) of the auxiliary rod (307) and the assisted joint (302), in such a way as to vary a preload of the elastic element (310). In general, the adjustment system (313) is additionally configured to vary a relative angle between the main rod (304) and the auxiliary rod (307).

[0071] For this purpose, the adjustment system (313) comprises a movable adjustment element (314) associated with the support structure (303).

[0072] Preferably, the adjustment system (313) further comprises an adjustment rod (320) connecting the movable adjustment element (314) to the second end (309) of the auxiliary rod (307). Preferably, the movable adjustment element (314) comprises a linear actuator (321) on which the adjustment rod (320) is articulated.

[0073] Preferably, the linear actuator (321) is movable along a ramp element (322) which is constrained to the support structure (303).

[0074] Figure 4a and Figure 4b illustrate exemplary performances of a load compensation device in accordance with the present invention.

[0075] In particular, Figure 4a illustrates a comparison between torques at the joint that are required from the user as a function of the rod rotation angle. Petition 870250015083, dated 25 / 02 / 2025, page 51 / 77 20 / 27 main (304) around the assisted junction, without the device of the present invention [line (400)] and with the load compensation device (301) [line (401)].

[0076] It can be noted that the effort required from the user is almost completely zero when using the device [line (401), for any angle value].

[0077] In particular, Figure 4b illustrates a different situation, in which it is assumed that the exoskeleton (100) is equipped with a motor that controls the rotation of the assisted joint (302) instead of the user, by supplying a torque, without the device of the present invention [line (402)] and with the load compensation device (301) [line (403)].

[0078] It can be noted how the total energy (calculated assuming that the angular velocity is constant) in the case of the exoskeleton (100), which is provided with the load compensation device of the present invention [line (403)], is almost zero throughout the entire working field, when compared with the energy in the case of an active exoskeleton with a motor, but without the device of the present invention [line (402)].

[0079] The performance examples demonstrate that the load compensation device of the present invention has the capacity to almost completely compensate for the gravitational effect, within the integrity of the working field, with minimal energy consumption.

[0080] For this reason, the load compensation device of the present invention makes it possible to use a lighter and less energy-consuming motor. Petition 870250015083, dated 25 / 02 / 2025, page 52 / 77 21 / 27 used, in favor of a lighter and more efficient overall system.

[0081] Figure 5 illustrates a second embodiment of a load compensation device (501) in accordance with the present invention.

[0082] The load compensation device (501) essentially comprises the elements already described in relation to the embodiment (301) presented with reference to Figure 3.

[0083] Compared with the previously described embodiment (301), the load compensation device (501) provides different overall geometries resulting in slightly different kinematic characteristics that enable adequate load compensation for a specific application.

[0084] Additionally, compared with the already described embodiment (301), the load compensation device (501) provides a linear actuator (321) that moves on a different ramp element (522), which is differently inclined and which is not directly connected to the assisted joint (302), but is nevertheless connected to the support structure (303).

[0085] In other words, the load compensation device (501) provides a regulating system (313) that always comprises a movable regulating element (314) associated with the support structure (303), and in which the linear actuator (321) is movable along a different ramp element (522) constrained to the support structure, wherein the ramp element (522) has a slope determined based on different Petition 870250015083, dated 25 / 02 / 2025, page 53 / 77 22 / 27 desired kinematic characteristics for the load compensation device (501).

[0086] Figure 6 illustrates a third embodiment of a load compensation device (601) in accordance with the present invention.

[0087] The load compensation device (601) essentially comprises the elements already described in relation to the embodiment (301) presented with reference to Figure 3.

[0088] Consequently, the load compensation device (601) employs the same operating principle described in relation to the previous embodiments (301) and (501), but uses a different adjustment system (613) within the hybrid mechanical structure.

[0089] In particular, the adjustment system (613) further comprises a cable (620) connecting the movable adjustment element (614) to the second end (309) of the auxiliary rod (307).

[0090] In this embodiment of the adjustment system (613), the movable adjustment element (614) comprises a motor-driven pulley (621) on which the cable (620) is adapted to wind or unwind. Consequently, the adjustment system (613) is configured to modify a distance between the second end (309) of the auxiliary rod (307) and the assisted joint (302), in such a way as to vary a preload of the elastic element (310). In general, the adjustment system (613) is additionally configured to vary a relative angle between the main rod (304) and the auxiliary rod (307). Petition 870250015083, dated 25 / 02 / 2025, page 54 / 77 23 / 27

[0091] Preferably, the motor-driven pulley (621) is in a fixed position with respect to the assisted joint (302), and a second distance between the motor-driven pulley (621) and the assisted joint (302) is determined based on desired kinematic characteristics of the load compensation device (601).

[0092] In other words, in this embodiment of the regulating system (613), the linear actuator (321) is replaced by a rotary actuator or motor (621), while the regulating rod (320) is replaced by a cable (620) that winds around the motor-controlled pulley (621).

[0093] Figure 7 illustrates an exoskeleton (700) engaging the pelvis and lumbar spine and comprising a load compensation device (701) in accordance with the present invention.

[0094] In this embodiment of the load compensation device (701), it is applied to exoskeletons for lumbar spine.

[0095] The load compensation device (701) is connected to a support structure (702) on which the forces are released. The compensation force is transferred from the device (701) to the limb by means of an element (704), during the leg movement imposed by the user around the hinge (3). The element (704) itself preferably contains the electronic components and power supply batteries for all active parts, while there are sensors for detecting the relative rotation between (703) and (704). Petition 870250015083, dated 25 / 02 / 2025, page 55 / 77 24 / 27

[0096] In general, the load compensation device is associated, in the exoskeleton, with a battery to supply power to the regulation system, a plurality of sensors and at least one processor.

[0097] Figure 8 illustrates a fourth embodiment of a load compensation device in accordance with the present invention.

[0098] The load compensation device (701) is applied to the exoskeleton (700) in such a way as to relieve stress in the lumbar spine area. In this case, the assisted joint (302) is that of the pelvis. The support structure, onto which the load compensation device (701) is fastened (closed), is composed of two parts, one that fastens onto the upper part of the leg and one that fastens onto the pelvis.

[0099] The load compensation device (701) follows the same implementation as the load compensation device (501) already described.

[0100] Figure 9 illustrates a fifth embodiment of a load compensation device (901) in accordance with the present invention.

[0101] The load compensation device (901) comprises some of the elements already described in relation to embodiments (301) and (501) shown with reference to Figure 3 and Figure 5.

[0102] in particular, the load compensation device (901) comprises an assisted joint (302) configured to be confined to a support structure (303).

[0103] Load compensation device Petition 870250015083, dated 25 / 02 / 2025, pp. 56 / 77 25 / 27 (901) additionally comprises a main shaft (304), comprising a proximal end (305), connected to the assisted joint (302), and a distal end (306) configured to be tensioned by the applied load (11).

[0104] The load compensation device (901) further comprises an auxiliary rod (307) comprising a first end (308) and a second end (309). The first end (308) is articulated on the main rod (304) for rotation of the auxiliary rod (307) with respect to the main rod (304). The second end (309) is movable on a plane on which the applied load (11) rests.

[0105] The load compensation device (901) further comprises an elastic element (910) configured to provide an elastic force acting between the second end (309) of the auxiliary rod (307) and the distal end (306) of the main rod (304).

[0106] In particular, the elastic element (910) is a tension spring that directly connects the second end (309) with the distal end (306). In a preferred embodiment, the elastic element (910) comprises a helical spring, but it could also be a strip made of rubber or an elastic material that is suitable for the purpose.

[0107] In one variation, the tension spring could connect outer portions of rods (304) and (309), without direct connection of their ends.

[0108] The load compensation device (901) additionally comprises a regulating system Petition 870250015083, dated 25 / 02 / 2025, pp. 57 / 77 26 / 27 (313) configured to modify a distance between the second end (309) of the auxiliary rod (307) and the assisted joint (302), in such a way as to vary a preload of the elastic element (910).

[0109] The regulating system (313) preferably corresponds to the embodiment already described with reference to Figure 5, with a linear actuator (321) that moves on a ramp element (522).

[0110] In general, the elastic element (910) is configured to provide the elastic force based on a kinematic configuration of the load compensation device (901), which is determined by the position of the main rod (304) and the auxiliary rod (307), and by the preloading of the elastic element (910).

[0111] In this case, the load compensation device (901) has the capacity to compensate for the load applied (11) to a component thereof that is transverse to the main rod (304). Industrial applicability

[0112] The present invention makes it possible for loads to be efficiently compensated, in particular gravitational loads.

[0113] The load compensation device in accordance with the present invention can be integrated inside exoskeletons that are particularly designed for industrial applications in which a user has to perform strenuous manual operations or generally bodily wear and tear, and for biomedical applications both for rehabilitation and assistance. Petition 870250015083, dated 25 / 02 / 2025, pp. 58 / 77 27 / 27

[0114] In this sense, the load compensation device in accordance with the present invention, which is integrated into an exoskeleton, enables a reduction of load on different joints, such as shoulder, lumbar spine, knee, hip, etc.

[0115] Additionally, the load compensation device in accordance with the present invention can also be integrated into robotic arms.

[0116] Considering the description reported here, a person skilled in the state of the art will have the capacity to conceive additional modifications and variations, in such a way as to satisfy contingent and specific needs.

[0117] The embodiments described herein are consequently to be regarded as illustrative and not limiting examples of the present invention, which are defined in the claims. Petition 870250015083, dated 25 / 02 / 2025, page 59 / 77

Claims

1 / 5 CLAIMS 1. Load compensation device (201, 301, 501, 601, 701, 901) comprising: - an assisted joint (3; 302) configured to be confined in a support structure (102, 104; 303; 702, 704); - a main rod (304) comprising a proximal end (305) connected to said assisted joint (3; 302), and further comprising a distal end (306) configured to be tensioned by an applied load (11); - an auxiliary rod (307) comprising a first end (308) and a second end (309), said first end (308) being articulated on said main rod (304) to rotate said auxiliary rod (307) relative to said main rod (304), said second end (309) being movable on a plane in which said applied load (11) is located;- an elastic element (310, 910) configured to provide an elastic force acting between said second end (309) of said auxiliary rod (307) and said distal end (306) of said main rod (304); characterized in that it further comprises: - a regulating system (313; 613) configured to modify a distance between said second end (309) of said auxiliary rod (307) and said assisted junction (3; 302), in such a way as to vary a pre-loading of said elastic element Petition 870250015083, dated 25 / 02 / 2025, page 66 / 77 2 / 5 (310, 910); wherein said elastic element (310, 910) is configured to provide said elastic force based on a kinematic configuration of said load compensation device (201, 301, 501, 601, 701, 901), in such a way as to compensate said applied load (11) on a component thereof that is transverse to said main rod (304).

2. Load compensation device, according to claim 1, characterized in that said adjustment system (313; 613) comprises a movable adjustment element (314; 614) associated with said support structure (303).

3. Load compensation device, according to claim 2, characterized in that said regulating system (313) further comprises a regulating rod (320) connecting said movable regulating element (314) to said second end (309) of said auxiliary rod (307), and wherein said movable regulating element (314) comprises a linear actuator (321) on which said regulating rod (320) is articulated.

4. Load compensation device, according to claim 3, characterized in that said linear actuator (312) is movable along a ramp element (352; 522) which is confined to said support structure (303), said ramp element (322; 522) having an inclination determined based on the desired kinematic characteristics of said load compensation device (201, 301, 501, 601, Petition 870250015083, dated 25 / 02 / 2025, p. 67 / 77 3 / 5 701, 901).

5. Load compensation device, according to claim 2, characterized in that said adjustment system (613) additionally comprises a cable (620), which connects said movable adjustment element (614) to said second end (309) of said auxiliary rod (307), and wherein said movable adjustment element (614) comprises a motor-driven pulley (621) on which said cable (620) is adapted for winding or unwinding.

6. Load compensation device, according to claim 5, characterized in that said motor-driven pulley (621) is in a fixed position relative to said assisted joint (302), and in that a second distance between said motor-driven pulley (621) and said assisted joint (302) is determined based on the desired kinematic characteristics of said load compensation device (201, 301, 501, 601, 701, 901).

7. Load compensation device, according to any one of claims 1 to 6, characterized in that said adjustment system (313; 613) is additionally configured to vary a relative angle between said main rod (304) and said auxiliary rod (307).

8. Load compensation device, according to any one of claims 1 to 7, characterized in that said adjustment system (313; 613) is additionally configured to minimize a difference between said transverse component of said applied load (11) and an opposing transverse component provided by said elastic force.

9. Load compensation device, according to any one of claims 1 to 8, characterized in that it further comprises a plurality of sensors configured to measure an absolute position of said main rod (304) and further measure a tensioning torque said assisted joint (3; 302) as a result of said applied load (11), and further comprising at least one processor operatively connected to said plurality of sensors and said regulating system (313; 613), configured to calculate said preload in such a way as to counterbalance said tensioning torque said assisted joint (3; 302).

10. Load compensation device, according to any one of claims 1 to 9, characterized in that said elastic element (310, 910) is at least indirectly connected to said second end (309) of said auxiliary rod (307).

11. Load compensation device, according to any one of claims 1 to 10, characterized in that it further comprises a compensation cable (311), said compensation cable (311) connecting said second end (309) of said auxiliary rod (307) to said elastic element (310).

12. Load compensation device, according to claim 11, characterized in that Petition 870250015083, dated 25 / 02 / 2025, page 69 / 77 5 / 5 said elastic element (310) develops axially and is parallel to said main rod (304), said load compensation device (201, 301, 501, 601, 701, 901) further comprising a pulley (312) in proximity to said distal end (306) of said main rod (304), said compensation cable (311) engaging said pulley (312).

13. Load compensation device, according to any one of claims 1 to 12, characterized in that said auxiliary rod (307) projects from said main rod (304) in a direction opposite to a prevailing direction of said applied load (11).

14. Load compensation device, according to any one of claims 1 to 13, characterized in that said distal end (306) of said main rod (304) corresponds to a clamp of a movable structural element (130; 703) subjected to variable loads.

15. Exoskeleton (100; 700), characterized in that it comprises at least one load compensation device (201, 301, 501, 601, 701, 901) as defined in any one of claims 1 to 14. Petition 870250015083, dated 25 / 02 / 2025, pp. 70 / 77

Images