Exoskeleton comprising elastic elements

Abstract

The invention relates to an exoskeleton (100) comprising: - an arm (110) comprising means for attaching an upper limb; - a load bearing structure (140) comprising a support point (141); - a compensation member (130) fixed to the arm by a first pivot (131), extending between the arm and the load bearing structure and exerting a compensation moment on the arm by deformation of an elastic element; - a force transmission element (150) extending between a low point of the compensation member and a rear end of the arm; - the elastic element and the force transmission element being continuously loaded in tension in use of the exoskeleton, configured in such a way that the moment varies with the inclination of the arm; - the transmission element being fixed to the arm by a second pivot (151), the first pivot being located between the second pivot and a front end of the arm.

Description

Technical Field

[0001] This invention relates to the field of exoskeletons, specifically mechanical structures that double the size of the human skeleton to assist in performing tasks or activities such as lifting and carrying loads.

[0002] In this article, the term “load” should be understood as the weight supported by the user, that is, the weight of his own upper limbs, which may bear the weight or force exerted by one or more objects being carried.

[0003] More specifically, the present invention relates to an exoskeleton including an elastic element that generates torque to compensate for load, thereby reducing the burden on the wearer of the exoskeleton when performing tasks or activities.

[0004] In particular, the present invention is applicable in the fields of medicine, military and manual / manual work, where the present invention allows for the specific prevention of musculoskeletal diseases. Background Technology

[0005] Exoskeleton technologies are known from existing technologies, which allow for the reduction of the wearer's load when performing painful, repetitive tasks, particularly those involving musculoskeletal disorders.

[0006] Existing technologies also include exoskeleton technology for medical and military purposes, designed to restore the physical functions of physically weak individuals or enhance the physical functions of physically healthy individuals.

[0007] Therefore, exoskeleton solutions using various mechanical devices are known, such as robotic devices that specifically involve actuator cylinders.

[0008] In particular, the disadvantages of such robotic systems are their large weight, high procurement and maintenance costs, and the need for access to energy sources such as electricity or hydraulics, which are typically heavy and bulky, embedded in the exoskeleton, and usually have low autonomy.

[0009] Purely mechanical systems are also known, meaning that these systems specifically do not include electromechanical or hydraulic mechanical actuators and do not require onboard power.

[0010] Many of these systems are based on the use of cables, pulleys, or rods arranged to support the wearer's limbs. The system is self-powered by storing energy supplied from outside the system in the form of elastic energy, which is achieved through the deformation of elastic elements caused by the wearer's limbs during movement.

[0011] This system can overcome some of the aforementioned drawbacks; however, known solutions in the prior art have proven to be cumbersome and include many components that affect the wearer's freedom of movement and ergonomics.

[0012] In addition, it is generally known that the central component of the system bears a great deal of force, thus requiring significant dimensional adjustments to increase the mass of the exoskeleton, or more frequent component replacements when seeking to optimize mass.

[0013] Currently, no single system can simultaneously address all the requirements: proposing a non-motorized and non-robotic exoskeleton technology that meets the standards for reduced quality, cost, and size, while also offering a simple design and a long service life. Summary of the Invention

[0014] The present invention aims to overcome all or part of the above-mentioned disadvantages of the prior art.

[0015] Therefore, the present invention relates to an exoskeleton adapted to assist at least one upper limb of the wearer during use when lifting and carrying loads. The exoskeleton includes:

[0016] - At least one arm, wherein at least one end of the arm, referred to as the "front end", includes at least one device for attaching to the upper limb of a wearer.

[0017] - A load-bearing structure designed to be secured to the wearer, including at least one support point.

[0018] - At least one compensating member, which is fixed to the arm via a first pivot and extends between the arm to which the compensating member is fixed and the load-bearing structure, and applies a compensating torque on the arm by the deformation of at least one elastic element.

[0019] - A force-transmitting element extending between the low point of the compensating member and an end of the arm opposite the front end, referred to as the "rear end," the exoskeleton comprising:

[0020] - At least one elastic element and a force transmission element, wherein the at least one elastic element and the force transmission element are continuously loaded under tension during use of the exoskeleton and are configured such that the torque varies with the tilt of the arm.

[0021] - The force transmission element is fixed to the arm via a second pivot located at the rear end of the arm, and a first pivot is located between the second pivot and the front end of the arm.

[0022] These arrangements enable fully self-powered exoskeleton technology, which reduces mass and size and eliminates the need for energy storage tanks because energy is stored in elastic elements.

[0023] In addition, the exoskeleton provides the user with assistance consistent with the force to be provided, that is, it provides compensating force, more specifically compensating torque. This assistance is more noticeable when the user is in a working position, such as when carrying a load, and less noticeable when the user is in a relaxed position (where the arms are along the body toward his feet).

[0024] Because the exoskeleton extends between the user's waist and upper limbs, the arms are positioned below the upper limbs during use. Therefore, the exoskeleton's arms are only stressed during bending, unlike known exoskeletons which are stressed during both bending and torsion, resulting in a longer lifespan and smaller size. More specifically, arms that are stressed during bending but not during torsion have a smaller profile compared to arms that are stressed during torsion. Furthermore, arms can be designed from composite materials, which have high bending resistance but low torsion resistance. For example, materials including glass fiber or carbon fiber can be used, resulting in exoskeleton arms with significantly reduced mass compared to known exoskeleton technologies.

[0025] Furthermore, the structure formed by the compensating member, arm, and force-transmitting element is self-constrained; that is, the aforementioned elements and their components form a structure balanced under the combined action of pressure and tension. Specifically, the force-transmitting element and elastic element are loaded purely under tension, while the other components of the compensating member and arm are loaded under compression. The arm also includes a point of load application, which, as mentioned above, is loaded during bending. Therefore, the self-constrained element system does not form a so-called perfect "tensioned whole" system, but comes very close to it. In particular, the mass of the arm is negligible in the absence of load, and the system is in a quasi-tensioned whole state. It should be understood that the equilibrium of this structure is dynamic, as it changes under load, and the elastic elements are able to achieve equilibrium through their variable tension.

[0026] The presence of a single elastic element enables the exoskeleton to achieve its "basic" output behavior. The compensating force felt by the user varies in a sinusoidal manner, with the maximum value felt at the so-called "working" position and the minimum value felt at the extreme positions of "low" and "high".

[0027] However, the exoskeleton according to the present invention may include a large number of elastic elements, which is theoretically unlimited. In practice, compensation members with multiple elastic elements connected in series or parallel can be designed to obtain various output behaviors of the exoskeleton. In particular, elastic elements with different elastic constants can be used to further modify the output behavior.

[0028] Furthermore, the multiplication of elastic elements allows for the design of compensation components of various shapes, especially curved ones, to fit the user's body lines as closely as possible.

[0029] Furthermore, depending on the exoskeleton's design, the compensating force increases from the extreme positions toward the intermediate positions, preferably increasing monotonically to enhance load compensation, which makes it increasingly difficult for the user to wear or carry. This is achieved in a way that provides smooth, progressive support, specifically, the force felt by the user follows a generally sinusoidal path, resulting in high compensation in positions around the working position and lower compensation in extreme positions where only moderate compensation is needed. Moreover, this change in upper limb position corresponds to a change in the force exerted by the upper limbs on the wearer's shoulders; therefore, the exoskeleton compensates for the load borne by the upper limbs in all its angular positions to permanently reduce the wearer's load.

[0030] In a particular embodiment of the invention, the arm includes a setting mechanism for setting the distance between the first pivot and the second pivot.

[0031] Because of these arrangements, the lever arm of the compensating force can be varied, thereby changing the available compensating torque. Therefore, in a very simple way, the user can adjust the exoskeleton's output "force" according to the type of task or activity he wants to perform.

[0032] In a specific embodiment of the present invention, the setting mechanism includes:

[0033] - An opening at a first pivot, in which the arm can slide.

[0034] - A setting plate located at one end of the arm, the setting plate being fixed to a worm gear that engages with a threaded opening of the first pivot.

[0035] Because of these features, the setup process is particularly easy and intuitive, enabling the exoskeleton to be widely used without requiring specific training in its use. Setup can also be performed independently by the user, without assistance or removal of the exoskeleton, allowing for "real-time" adjustment of the required torque based on the exoskeleton's operating conditions.

[0036] In a particular embodiment of the invention, the compensation member includes an elastic element.

[0037] - When the upper limb is in the so-called first extreme "high" position, the elastic element is in a state of minimum tension.

[0038] - When the upper limb is in the so-called second extreme "relaxed" position, the elastic element is in a state of maximum tension.

[0039] - The tension of the elastic element causes the compensation member to retract. When the upper limb is in the high position and the relaxed position, the compensation member is in the extended state and the maximum retracted state, respectively.

[0040] Due to these arrangements, the compressive force of the compensating components acts on the arms of the exoskeleton, while the elastic elements generate a tensile force, which is simpler than the elements that generate a compressive force.

[0041] The arms of an exoskeleton experience a torque that tends to pivot the arm about a point of rotation toward a relaxed position. By using a compensating member acting in compression, a compensating force (from which the compensating torque originates) can be applied between the point of rotation and the point of load application. Conversely, many known systems in the prior art where the compensating member acts under tension are forced to apply a compensating force opposite to the point of load application, thus lengthening the exoskeleton's arm and increasing its size. Therefore, this design solves the problem that has been unsolvable until now: obtaining an exoskeleton with a compact arm that does not protrude significantly from the wearer's body, while using a resilient tension element that is lighter, cheaper, and smaller than its equivalent compression element.

[0042] In a particular embodiment of the present invention, the compensation component includes

[0043] - A backswing; and

[0044] - A downswing, the upswing and downswing are parallel, and

[0045] - The upper end of the lower rod is fixed to the upper plate, and

[0046] - The lower end of the upper rod is fixed to the lower plate.

[0047] The upper and lower rods slide in the openings of the upper and lower plates, respectively, and the elastic element extends between the upper and lower plates.

[0048] Because of these arrangements, the exoskeleton according to the invention can be manufactured using simple, inexpensive, and readily available components.

[0049] Furthermore, due to these features, the compensating member possesses sufficient rigidity and a simple design. The resulting kinematic characteristics are thus able to compensate for the device's doubled length in the deployed state.

[0050] Furthermore, the design using two parallel bars (or tubes) reduces the locations of noticeable cantilever on each bar. In effect, these locations are limited to the deployed or near-deployed position; in the remaining positions, the upper and lower plates reduce the cantilever length of each bar, thus significantly limiting the risk of bar buckling.

[0051] Existing solutions propose that the compensating element extends beyond the upper limb in the direction of the user's shoulder and typically consists of a single rod or tube. In contrast, the design proposed in this invention limits the length of the compensating element to the distance between the support point and the first pivot, approximately the distance from the user's waist to the upper limb. This distance is covered by two rods guided by a plate, significantly reducing the risk of buckling compared to known prior art. Therefore, rods or tubes of significantly reduced size can be used compared to known solutions, resulting in greater weight reduction of the exoskeleton.

[0052] In a particular embodiment of the invention, the at least one elastic element is an elastic cable comprising an elastic core preferably made of rubber and a protective sheath preferably made of an elastic braided material.

[0053] Because of these arrangements, the elastic element is composed of particularly light, inexpensive and readily available components.

[0054] In a particular embodiment of the invention, the force transmission element comprises an elongated element that has essentially no elastic deformation capability.

[0055] In a particular embodiment of the invention, the force transmission element includes two elongated elements extending parallel to each other on both sides of the compensating member.

[0056] In this way, the force transmission element is positioned on either side of the compensation member, thereby making the design of the exoskeleton according to the invention particularly compact.

[0057] In a particular embodiment of the invention, the elongated element is a cable.

[0058] Due to these arrangements, the exoskeleton according to the invention is particularly lightweight without sacrificing structural performance, the force transmission elements are only stressed under tension, and it can be made of cables.

[0059] In a particular embodiment of the invention, the support point is a spherical shell, and the compensation member includes a spherical head to form a ball-and-socket joint connection.

[0060] Because of these arrangements, the compensating components and the arms of the exoskeleton can rotate around all axes of space, thus maintaining the user's freedom of movement in the upper limbs.

[0061] In a particular embodiment of the invention, the load-bearing structure is a pelvic belt adapted to clamp the wearer's hips and / or waist.

[0062] Because of these arrangements, the exoskeleton remains in a specific area of ​​the user's body, allowing the user to exert significant force and thus helping to reduce the risk of injury or musculoskeletal disorders.

[0063] It should also be noted that the exoskeleton is only held in the user’s waist / hips and upper limbs, but the shoulders, in particular, do not require other support devices (e.g., via braces).

[0064] In a particular embodiment of the invention, the attachment device includes a longitudinal pad that, when the exoskeleton is in the so-called “working” position, intersects the projection of the pad’s axis onto the so-called “horizontal” plane at an angle between 0 and 30 degrees.

[0065] Because of these arrangements, there is no risk of the exoskeleton colliding with the user's ribs, abdomen, or armpits, thus improving the safety and comfort of using the exoskeleton.

[0066] Therefore, when in the working position, the user can also move more than 90° to his right and left, and due to the aforementioned arrangement, the risk of collision between the exoskeleton and the user is suppressed. Attached Figure Description

[0067] Other advantages, objects, and specific features of the invention will become apparent from the following non-limiting description of at least one particular embodiment of the apparatus and method of the invention with reference to the accompanying drawings.

[0068] Figure 1 This is a schematic perspective view of an exoskeleton worn by a user according to the present invention.

[0069] Figure 2 This is a schematic 3D diagram of an independent exoskeleton in its so-called "working" position.

[0070] Figure 3 This is a schematic 3D diagram of an independent exoskeleton in a so-called "relaxed" position.

[0071] Figure 4 It is a schematic 3D diagram of an independent exoskeleton in a so-called "high" position.

[0072] Figure 5 It is a graph showing the change of the compensating force as a function of the tilt angle of the arm relative to the horizontal plane.

[0073] Figure 6 This is a top view of the exoskeleton in its so-called "working" position.

[0074] Figure 7 It is a 3D diagram of the exoskeleton in the so-called "working" position, where the user's arms are outstretched and the module's arms do not collide with the sides of the body. Detailed Implementation

[0075] This description is given in a non-limiting manner, and each feature of the embodiments can be advantageously combined with any other feature of any other embodiment.

[0076] It should be noted that the accompanying drawings are not drawn to scale.

[0077] This invention relates to Figure 1 The exoskeleton 100 shown is in a state worn by an individual 200 (hereinafter also referred to as the "user" or "wearer"). It should be noted that although the exoskeleton 100 generally comprises a right module 101 adapted to relieve the weight of the user's right upper limb 201 and a left module 102 adapted to relieve the weight of the user's left upper limb 202, for the sake of brevity, only one of the two modules, namely the left module 102, will be referred to later, and the term "left" will also be omitted for brevity. It is also noted that the right module 101 and the left module 102 are structurally identical or similar and symmetrical with respect to the wearer.

[0078] Depending on the desired application or the user's physical characteristics, an exoskeleton 100 consisting of only one module (right or left module) can also be manufactured.

[0079] like Figure 1 As illustrated, each module of the exoskeleton is designed to reduce the load on the corresponding upper limb, that is, to reduce the force exerted by the user, thereby generating muscle activity and thus, in particular, lower cardiac and respiratory activity. In this way, the user experiences less physical exertion, thus enabling the user to maintain their health.

[0080] Conversely, with the same amount of force exerted, the user's physical capabilities can also be improved (compared to the case without the exoskeleton according to the invention). In other words, the user's ability to lift, carry, or hold loads can be increased, i.e., conversely, the perceived weight of the load is reduced.

[0081] More specifically, the forces generated on the exoskeleton ( Figure 1 (Not shown in the image) mainly corresponds to the weight of the load.

[0082] It should be easy to understand that this load is applied to the exoskeleton in the form of force and torque, and the force applied by the load often counteracts the force exerted by the user 200. Therefore, the primary function of the exoskeleton is to resist the force applied by the load and to support the force exerted by the user 200.

[0083] Figure 2The left module 102, comprising an arm 110, is positioned in a so-called "working" or "intermediate" position. The arm 110 is generally horizontal, as is the user 200's left upper limb, although the arm 110 may not be parallel to the user's upper limb. "Generally horizontal" should be understood as being generally parallel to the ground and generally orthogonal to the user 200's body. Therefore, when the user 200 stands in this characteristic position, the arm 110 and upper limb are oriented forward. This position is referred to as the "working" position because it corresponds to, for example, a position where the user 200 is carrying a load or holding a tool.

[0084] Figure 3 The module 102 is shown in a so-called “relaxed” or first extreme “low” position, where, when the user 200 is standing, the user 200’s upper limbs are generally vertical, i.e., generally perpendicular to the ground and generally parallel to the user 200’s body, and oriented downwards. This position is called the “relaxed” position because it corresponds to the position where the user 200’s arms and hands are aligned downwards along the body, making it generally impossible to perform tasks or activities.

[0085] However, it should be noted that in this characteristic position, arm 110 is not strictly vertical, but rather forms an angle between 0° and 45° with the user's upper limb in a plane parallel to the wearer's sagittal plane. However, from a mechanical point of view, this position actually corresponds to the extreme position of the arm, in which the exoskeleton is almost completely retracted, as... Figure 3 As shown.

[0086] Figure 4 Module 102 indicates a so-called second extreme "high" position, where, when user 200 is standing, user 200's upper limbs are generally vertical, i.e., generally perpendicular to the ground and generally parallel to user 200's body, and oriented upwards. This extreme "high" position is not strictly defined as the vertical position of arm 110, but rather as a position within an angle range of approximately 15° forward from the vertical direction. This so-called "high" position corresponds to a position where user 200's arms and hands are substantially parallel to the user's body and oriented upwards, for example, to reach objects located at a height or to use tools above the user.

[0087] like Figure 4 As shown, even in this extremely "high" position, the exoskeleton is not fully deployed to provide assistance to the user. Furthermore, this slight bending of the exoskeleton causes it to retract, i.e., shift towards a position closer to the center.

[0088] Therefore, it should be understood that in use, the exoskeleton 100 is oriented according to the body of the user 200, who represents a reference system in his standing position, particularly in the so-called “working” position, which allows the identification of relative positions referred to as “high,” “low,” “front,” and “back,” as well as “up” and “down.”

[0089] Especially Figures 2 to 4 As shown, the arm 110 of the exoskeleton 100 module includes a device 120 for attaching the upper limb 102 of the wearer 200. Therefore, in use, the arm 110 of the exoskeleton is generally parallel to the upper limb 102, and more specifically, parallel to the arm of the upper limb. However, it is not parallel, particularly in positions close to the extreme “relaxed” and “high” positions.

[0090] A compensating member 130, having a generally longitudinal shape, is pivotally fixed to the arm 110 via a first pivot 131. Specifically, as... Figure 2 As shown, the axis of the first pivot 131 is substantially perpendicular to the arm 110 and the compensating member 130. It should be noted that the reference numeral 131 subsequently refers to the first pivot from a mechanical perspective, but also to the portion of the structure where the pivot point is located.

[0091] The load-bearing structure 140, including support point 141, supports the compensation member 130 and supports the arm 110 by extension.

[0092] In other words, the compensation member 130 is located between the load-bearing structure 140 and the arm 110.

[0093] Advantageously, the load-bearing structure 140 is a pelvic (or abdominal) belt, which is adapted to clamp the wearer's hips and / or waist, depending on how the user wears the exoskeleton 100.

[0094] Advantageously, this belt is made of textile material and preferably includes at least one adjustable closed buckle. It is also possible to consider a safety belt with a buckle, which is advantageously positioned opposite the closed buckle to increase the possible range of adjustment.

[0095] In this example, support point 141 is fixed to support plate 142 on load-bearing structure 140 and is provided with spherical shell.

[0096] The compensating member 130 has a spherical head at its so-called "low" end, that is, at its end near the load-bearing structure 140, which is adapted to be inserted into the spherical shell of the support plate 142 to form a ball-and-socket joint connection, thereby enabling the compensating member 130 to achieve three independent rotational degrees of freedom relative to the load-bearing structure 140.

[0097] However, in some combinations, it may be desirable or necessary for the compensating member 130 to have only two, one, or no rotational degrees of freedom with respect to the load-bearing structure 140. In such cases, the ball joint connection can be replaced by, for example, a double-pivot, a single-pivot, or an insert.

[0098] The compensating member 130 applies a compensating torque to the arm 110, which varies with the position of the upper limb 202 and therefore with the position of the arm 110.

[0099] Advantageously, the compensating torque is generated by the deformation of the elastic element 132 of the compensating member 130. Therefore, it should be understood that the energy available to the user is stored only in the elastic element 132 in the form of elastic energy, without the need for other energy sources, thus giving the exoskeleton a high degree of portability, compactness and autonomy.

[0100] More specifically, the compensating torque is greatest when the upper limb 202 is in the so-called intermediate "working" position. This feature is particularly advantageous because in this position, the user 200 most needs the assistance of the exoskeleton 100.

[0101] When the upper limb 202 is in the so-called “relaxed” or first extreme “low” position, a first minimum compensation torque is applied.

[0102] When the upper limb 202 is in the so-called second extreme "high" position, a second minimum compensation torque is applied.

[0103] Advantageously, the two minimum compensation torques are essentially zero so that no force is applied to the user when the user's upper limb 202 is in a "high" or "low" position.

[0104] Furthermore, the torque increases from the so-called first extreme "high" position to the so-called "working" intermediate position; and decreases from the so-called "working" intermediate position to the so-called "relaxed" second extreme position. More specifically, the torque also varies monotonically within the two aforementioned ranges to provide a continuously increasing compensating torque when switching from one of the two extreme positions to the intermediate position.

[0105] Figure 5 The diagram illustrates the function of the compensating force F_comp applied by the exoskeleton 100 to the upper limb 202 as the arm 110 tilts relative to the horizontal plane. The compensating force F_comp is an alternative representation of the compensating torque, allowing the user to immediately understand the perceived compensation.

[0106] Therefore, in Figure 5In this example, the compensating force F_comp (in Newtons [N]) is a function of the angle (in degrees) formed between the arm 110 and the horizontal axis, with a maximum compensating force of approximately 45 N. In other words, in this example, the exoskeleton 100 can compensate for a load of slightly more than 4.5 kg carried by the user (when the arm 110 is at 0° relative to the horizontal plane).

[0107] like Figure 5 As shown, at the extreme position corresponding to the arm 110 tilting + / - 90° relative to the horizontal plane, the compensation force is 0.

[0108] It should be noted that Figure 5 The force F_arm, applied to arm 110 by the compensating member, is also shown, with its maximum value slightly offset toward the so-called “relaxed” position.

[0109] As previously mentioned, the energy source that generates torque during the movement of the upper limb 202 is the elastic element 132.

[0110] The elastic element 132 is located on the compensating member 130. According to an advantageous embodiment, the compensating member includes an upper rod 133 and a lower rod 134, which are parallel. The upper end of the lower rod 134 is fixed to the upper plate 135, and the lower end of the upper rod 133 is fixed to the lower plate 136. The upper rod 133 slides in an opening in the upper plate 135, and the lower rod 134 slides in an opening in the lower plate 136. In other words, the upper rod 133 and the lower rod 134 can slide to occupy multiple positions of the compensating member 130 between a retracted limit state and an extended limit state, in which they face each other along their entire length, and in the extended limit state, the two plates are close to or in contact with each other.

[0111] The elastic element 132 extends between the upper plate 135 and the lower plate 136 to which it is fixed, preferably a tension spring, more preferably an elastic cable. Therefore, the switching of the compensation member 130 from the retracted state to the extended state causes the elastic element 132 to stretch; in other words, the elastic element 132 tends to drive the compensation member 130 into the retracted state.

[0112] Alternatively, by using a rod that slides within the tube, the compensating member 130 can be made more compact, with the elastic element fixed to both the upper end of the tube and the lower end of the rod. Therefore, the tension in the elastic element causes the rod to retract within the tube, and the compensating member, positioned in a compressed state, attempts to return to a retracted state where the elastic element is under minimum tension. This solution offers the advantage of being very compact, limiting the size to the dimensions of a single tube rather than two.

[0113] Therefore, it should be understood that the elastic element 132 is primarily subjected to stress under tension and is continuously subjected to stress during the use of the exoskeleton 100 to maintain the exoskeleton 100 in a state of equilibrium. The connections between the elements are not mechanically perfect, and other stresses (minor and negligible) may also exist.

[0114] Advantageously, the elastic element 132 is an elastic cable comprising an elastic core preferably made of rubber and a protective sheath preferably made of an elastic braided material. Such cables are known in the prior art, particularly cables or slings referred to as "Sandow".

[0115] The load applies a force at attachment 120, thus applying a torque around arm 110, which is rotatable.

[0116] To resist the torque applied by the load, a force transmission element 150 with no elastic deformation capability preferably extends between the low point of the compensation member 130 and the rear end of the arm 110 opposite to the front end of the arm 110.

[0117] More specifically, in this embodiment, the low point of the compensation member is the lower fastening portion 137 of the support rod 138 located between the lower plate 136 and the load-bearing structure 140. The support rod 138 also has the spherical head described above at its so-called "low" end.

[0118] The force transmission element 150 is attached to the rear end of the arm 110 using an upper fastening portion fixed to the arm 110, thereby forming a second pivot 151 about which the arm 110 can pivot. Figure 4 As shown, the upper fastening part forms a notch that can fit around the upper rod 133 to increase the range of motion of the arm 110.

[0119] The force transmission element 150 can be a longitudinally rigid part, such as a rod or tube. However, the force transmission element 150 is preferably subjected only to tensile forces, which advantageously includes cables and elements for fastening the cables, thereby making the outer frame 100 lighter and simpler in design.

[0120] In particular, this cable is made of metallic material, advantageously constructed of braided steel wire, and is specifically referred to in the prior art as so-called "Bowden" cable. In its intended use in this invention, this cable is analogous to a rigid element such as a rod or tube, which is considered to have a substantially constant longitudinal dimension under tension, similar to a slender element with essentially no capacity for elastic deformation.

[0121] like Figures 2 to 4 As shown, the force transmission element 150 is advantageously composed of two cables that extend parallel and symmetrically on both sides of the compensation member 130.

[0122] Therefore, it should be understood that the force transmission element 150 is primarily subjected to force under tension and is continuously subjected to force during the use of the exoskeleton 100 to maintain the exoskeleton 100 in a state of equilibrium. The connections between the elements are not mechanically perfect, and other stresses (minor and negligible) may exist.

[0123] Furthermore, the support rod 138 is substantially retractable into the component 134, in which case the component is the lower tube rather than the lower rod. The lower fastening portion 137 is secured to the lower tube 134 and allows adjustment of the relative axial position of the support rod 138 and the lower tube 134. For example, this adjustable fastening is achieved via a bolt mechanism, advantageously equipped with knobs to simplify setup without tools and allow for direct adjustment by the user while the exoskeleton is being worn.

[0124] It should be easy to understand, especially in the middle position, that the force transmission element causes the arm 110 to tend to rotate about the first pivot 131 by bearing the torque generated by the load.

[0125] Conversely, the force generated by the load is compensated by the elastic element 132, which generates a compensating force through its deformation.

[0126] During the movement of arm 110, the compensating member 130 is substantially retracted or extended by the constant length of force transmission element 150 and the kinematic characteristics of exoskeleton 100.

[0127] During the movement of arm 110, the force applied by the elastic element changes and reaches its maximum value when arm 110 is in the position corresponding to the so-called "low" position. However, the lever arm formed between the first pivot 131 and the rear end of arm 110 (orthogonal to the force applied by the elastic element) is thus zero. Conversely, in the so-called "high" position, the elastic element applies a minimum force, in which the force roughly corresponds to the weight of the load, and the auxiliary force is thus almost zero.

[0128] In fact, at this extremely high position, the first pivot 131 and the second pivot 151, as well as the point of application of the load represented by component 115, are on a straight line, and the lever arm of the compensating force is thus 0.

[0129] Therefore, it should be understood that the assistance provided by the exoskeleton is slightly greater in the position range between the "low" position and the "working" position because the elastic element 132 applies a larger force in this range.

[0130] As previously stated, the compensation provided by the exoskeleton depends on the lever arm of the force orthogonal to the elastic element, which is formed between the first pivot 131 and the rear end of the arm 110, i.e., the distance between the first pivot 131 and the rear end of the arm 110.

[0131] The desired compensation depends on the type of activity, load, and user configuration. The distance between the first pivot 131 and the rear end of the arm 110 can be adjusted via the setting mechanism of the arm 110.

[0132] Advantageously, the arm 110 consists of a rod 111 that can slide into an opening in a first pivot 131 located on the portion of the first pivot fixed to the arm 110.

[0133] The arm 110 includes a mounting plate 112 at its rear end, which also includes a fastening portion (or is consistent with) the force transmission element 150.

[0134] A worm gear 113 is provided in the setting plate 112, which can rotate freely in the setting plate 112 without translating relative to the setting plate.

[0135] The worm 113 engages with the threaded opening of the portion of the first pivot 131 that is fixed to the arm 110, so that the worm 113 extends parallel to the arm 110.

[0136] Therefore, the rotation of the worm 113 causes it to translate relative to the first pivot 131, and thus causes the arm 110 to translate relative to the first pivot 131, the arm 110 being fixed to the worm 113 via the mounting plate 112.

[0137] This setting mechanism is particularly easy to use and can be operated by the user. Ease of use is further improved by placing a knob at the head of the worm gear 113, eliminating the need for additional setting tools.

[0138] Advantageously, to reduce the torque applied by the user to the setting screw head, the setting mechanism needs to integrate friction-reducing elements based on the setting requirements. More specifically, the worm gear 113 can be supported by bearings, sliding bearings, or lubricated bushings. In this way, the lever arm can be set when the exoskeleton is in the working position, allowing the user to set the lever arm "in real time" during use in a particularly intuitive manner.

[0139] As previously described, the upper limb 202, more specifically the arm, is fixed to the attachment device 120. The attachment device 120 may consist of a single arm guard fixed to the arm 110, however, it advantageously consists of a double rigid arm guard.

[0140] For this purpose, a mounting bracket 115 fixed to the front end of arm 110 mates with a mounting U-shaped connector 121 of attachment device 120. The bracket 115 and U-shaped connector 121 are connected, for example, by a clearance-filled bolt arrangement, allowing the attachment device to rotate relative to arm 110. This rotation is limited within a given angular range, allowing a smooth transition from so-called “relaxed” and extremely “high” positions to intermediate positions. Rotation is limited, for example, by using a bolt parallel to the mounting bolt of attachment device 120, such that the bolt abuts against the bracket 115 at a first extreme angular position. A second extreme angular position is defined by a longitudinal pad abutting against arm 110, as described below.

[0141] The U-shaped connector 121 is fixed to the longitudinal padding (rigid or flexible) 122, which advantageously expands at the end near the wearer's elbow during use. Advantageously, the padding 122 extends along a portion of the upper arm in the direction of the wearer's shoulder.

[0142] In this way, the user's arm is supported for most of its length, thus improving the comfort and efficiency of the exoskeleton 100.

[0143] To hold the user's arm on the padding 122, the padding is provided with at least one, preferably two (or more) arm guards 124, preferably made of a textile material, thereby enabling the upper limb 202 to be attached to the exoskeleton. Advantageously, such arm guards have two attachment straps, each including complementary fastening devices designed to cooperate with each other. These fastening devices can indiscriminately consist of elements in the form of hooks or buckles designed to cooperate with each other, with the hooks temporarily hooking onto the buckles. This fastening device is referred to by those skilled in the art as "Velcro®" and allows for adjustment of the attachment according to the user's physique.

[0144] Using two (or more) arm guards 124 restricts the degree of freedom of the upper limb relative to the attachment device 120. In practice, using a single arm guard made of flexible material leaves a large degree of rotational freedom for the upper limb on the attachment device 120; in other words, there is a large ball-and-socket joint or angular clearance between the upper limb and the attachment device 120. In this situation, the user's movements (in other words, the forces generated) are not entirely used to pivot the exoskeleton's arm 120, nor does the arm closely follow the user's natural movements. Therefore, using at least two arm guards 124 spaced at a non-zero distance improves user comfort and exoskeleton efficiency.

[0145] Advantageously, such as Figure 6 As shown, when the exoskeleton is used in the “middle” or “working” position, the support 115 is not aligned with the axis of the arm 110, but forms an angle 160 between 0 and 30 degrees in the so-called “horizontal” plane (parallel to the ground).

[0146] In other words, in the “working” position, the projection of the axis of symmetry of the attachment 120 through the pad 122 and the projection of the axis of the arm 110 on the horizontal plane intersect at an acute angle 160 between 0 and 30 degrees.

[0147] In this way, such as Figure 7 As shown, the rear end of arm 110 is slightly away from the user orientation to avoid collision between arm 110 and the user's side.

[0148] According to an alternative embodiment, the exoskeleton according to the invention comprises more than one plurality of elastic elements.

[0149] Many combinations are possible, so an exhaustive description of these combinations cannot be given, and it should be understood that any “self-constrained” type structure based on the same design principles is feasible.

[0150] For example, an elastic element 132, similar to a tension spring, is integrated in series and / or parallel with the compensation member 130. However, compared to the aforementioned preferred embodiment with a single elastic element, the same output behavior (e.g., ...) can be achieved using an elastic element 132 with a lower elastic constant and smaller size. Figure 5 (As shown).

[0151] With comparable performance, this solution offers the advantage of greater design freedom in terms of geometry; in this example, the compensating member 130 can be bent to match the shape of the user's body.

[0152] According to a variation, the elastic constant and length of the elastic element 132 are different in order to obtain a different result. Figure 5 The output behavior shown.

[0153] Therefore, for positions around the work location, more constant behavior can be obtained; that is, the compensating force perceived by the user is almost constant over a wide angle range. This behavior may be ideal for activities where the load does not vary depending on the angle formed by the arm and the horizontal plane.

Claims

1. An exoskeleton (100) suitable, in use, to assist at least one upper limb (202) of a wearer of the exoskeleton in lifting and carrying a load, the exoskeleton comprising: at least one arm (110) comprising, at one of its ends, referred to as "front end", at least one means (115) for attaching an upper limb of the wearer; a load carrying structure (140) intended to be fixed to the wearer, comprising at least one support point (141); at least one compensation member (130) fixed to the arm by a first pivot (131) and extending between the arm to which it is fixed and the load carrying structure, at least one said compensation member exerting a compensation moment on the arm by deformation of at least one elastic element (132); and a force transmission element (150) extending between a low point of the compensation member and an end of the arm, opposite the front end, referred to as "rear end"; the exoskeleton being characterized in that: the at least one elastic element and the force transmission element are continuously loaded under tension during use of the exoskeleton and are configured so that the compensation moment varies with the inclination of the arm, the transmission element being fixed to the arm by a second pivot (151) located at the rear end of the arm, the first pivot being located between the second pivot and the front end of the arm.

2. The exoskeleton (100) according to claim 1, characterized in that the arm (110) comprises a setting mechanism for setting the distance between the first pivot (131) and the second pivot (151).

3. Exoskeleton (100) according to claim 2, characterized in that the setting mechanism comprises: an opening of the first pivot in which the arm can slide, and a setting plate (112) located at an end of the arm, the setting plate being fixed to a worm (113) cooperating with a threaded opening of the first pivot.

4. Exoskeleton (100) according to one of claims 1 to 3, characterized in that the compensation member (130) comprises an elastic element (132), - when the upper limb (202) is in a so-called first extreme "high" position, the elastic element is in a minimum tension state, and - when the upper limb is in a so-called second extreme "relaxed" position, the elastic element is in a maximum tension state, and - the tension of the elastic element causes the compensation member to retract, the compensation member being in an unfolded state and in a maximum retracted state when the upper limb is in the high position and in the relaxed position, respectively.

5. The exoskeleton (100) according to claim 1, the compensation member (130) comprising an upper bar (133), and a lower bar (134), the upper bar and the lower bar being parallel; an upper end of the lower bar being fixed to an upper plate (135), a lower end of the upper bar being fixed to a lower plate (136), the upper bar and the lower bar sliding in openings of the upper plate and the lower plate, respectively, and the elastic element (132) extending between the upper plate and the lower plate.

6. The exoskeleton (100) according to claim 1, the at least one elastic element (132) being an elastic cable comprising an elastic core made of rubber and a protective sheath made of a woven material having elasticity.

7. The exoskeleton (100) according to claim 1, the force transmission element (150) comprising an elongated element having substantially no elastic deformation capability.

8. The exoskeleton (100) according to claim 7, the force transmission element (150) comprising two elongated elements extending parallel to each other on both sides of the compensation member.

9. The exoskeleton (100) according to claim 7, the elongated element being a cable.

10. The exoskeleton (100) according to claim 1, the support point (141) being a spherical housing, the compensation member comprising a spherical head so as to form a ball-and-socket joint connection.

11. The exoskeleton (100) according to claim 1, the load bearing structure (140) being a pelvic belt adapted to clamp the hip and / or the waist of the wearer.

12. The exoskeleton (100) according to claim 1, the attachment means comprising one longitudinal pad (122), the axis of the pad and the projection of the axis of the arm on the so-called "horizontal" plane intersecting at an angle (160) comprised between 0 and 30 degrees when the exoskeleton is in the so-called "working" position.

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