EXOSKELETON STRUCTURE

FIELD OF THE INVENTION

An exoskeleton structure is disclosed.

STATE OF THE ART

Exercise-assist exoskeletons are mechanical structures that double the structure of the human skeleton and which improve the physical capacities of the human body.

There are different types of exercise support exoskeletons that depend on the tasks to be performed by the user. Each type of exoskeleton makes it possible to limit or reduce the effort provided by the user when performing certain tasks.

However, the user must support the weight of the exoskeleton structure when this weight is not transferred to the ground, which has the consequence of limiting the user's freedom of movement and generating an additional load which is necessarily transferred to the user's lower body.

Also, for a user, it may be difficult to put on or take off the exoskeleton structure.

SUMMARY OF THE INVENTION

An aim of the invention is to provide an exoskeleton structure which is more comfortable and which hinders the movements of the user as little as possible.

This aim is achieved in the context of the present invention by virtue of an exoskeleton structure comprising:

- a leg piece intended to be attached to a user's leg,

- a foot piece intended to be attached to a user's foot,

- a mechanical connecting assembly connecting the leg piece to the foot piece, comprising a first pivot allowing rotation of the foot piece relative to the leg piece about a first axis of rotation during a movement of internal / external rotation of the user's foot, and a

second pivot allowing rotation of the foot piece relative to the leg piece about a second axis of rotation during an eversion / inversion movement of the user's ankle,

wherein the first pivot is arranged such that the first pivot is disposed on one side of the leg piece, the leg piece lying between a user's sagittal plane and the first pivot, and the first pivot is located at a height greater than or equal to 20 centimeters from the ground when the user is standing on the ground, in the anatomical reference position, the first axis of rotation being oriented so that the distance between the first axis of rotation and the second axis of rotation is less than or equal to 5 centimeters.

It will be recalled that a “distance between two axes” is defined as the smallest distance which separates two points situated respectively on each of the two axes.

The invention is based on the observation that by positioning the first pivot sufficiently far from the user's ankle (that is to say at a certain height from the ground), it is possible to arrange the first axis of rotation so that it is as close as possible to the real center of rotation of the ankle. In particular, the first axis of rotation can be arranged so as to be sufficiently close to the second axis of rotation (that is to say at a distance between the axes less than or equal to 5 centimeters) so as to reproduce as faithfully as possible. possible the degrees of freedom of the ankle and thus obtain a more comfortable exoskeleton structure.

Further, the first pivot is disposed on one side of the leg piece such that the leg piece is between a user's sagittal plane and the first pivot.

This arrangement of the first pivot frees up the space in front of the user's tibia, as well as the internal space of the leg. In this way, the exoskeleton structure can be put on and taken off more easily. In addition, this limits the risks of interference between the exoskeleton structure and the user's other foot when walking.

Furthermore, this arrangement allows a lighter and less bulky design of the various parts of the structure.

In a preferred embodiment of the invention, the first axis of rotation is oriented such that it intersects the second axis of rotation (i.e. the distance between the axes is zero). The first axis of rotation and the second axis of rotation being concurrent, they make it possible to preserve the degrees of freedom of the ankle.

The proposed exoskeleton structure may also have the following characteristics:

- the first axis of rotation is oriented so that it forms a first non-zero angle with respect to a vertical direction when the user is standing, in the anatomical reference position, the first angle being between 1 and 30 degrees, preferably between 10 and 15 degrees, for example equal to 12 degrees,

- the mechanical connecting assembly comprises a third pivot allowing rotation of the foot piece relative to the leg piece about a third axis of rotation during a flexion / extension movement of the user's ankle ,

- the third pivot is placed at a height less than the height of the user's malleolus when the user is standing, in the anatomical reference position,

- the third pivot is placed towards the rear of the user's foot relative to the user's malleolus,

- the first axis of rotation is oriented so that the distance between the first axis of rotation and the third axis of rotation is less than or equal to 5 centimeters,

- the third axis of rotation is oriented so that it intersects the third axis of rotation,

- the third axis of rotation is oriented so that it forms a second non-zero angle with a frontal plane of the user when the user is standing, in the anatomical reference position, the second angle being between 1 and 15 degrees, preferably between 4 and 7 degrees, for example equal to 6 degrees,

- the third axis of rotation is oriented so that it forms a third non-zero angle with a transverse plane of the user when the user is standing, in the anatomical reference position, the angle being between 5 and 15 degrees, preferably between 6 and 8 degrees, for example equal to 8 degrees.

- the mechanical connecting assembly comprises a connecting part having a first end connected to the leg part via the first pivot and a second end connected to the third pivot, the connecting part comprising two parts mounted to slide one relative to the other in order to adjust a length of the connecting piece, and a locking device to lock the two parts with respect to each other once the length has been adjusted,

- the second axis of rotation is oriented so that it forms a fourth non-zero angle with respect to a horizontal direction when the user is standing, in the anatomical reference position, the angle being between 1 and 30 degrees , preferably between 15 and 25 degrees, for example 18 degrees,

- the second axis of rotation is oriented so that it passes below the user's malleolus when the user is standing, in the anatomical reference position,

the second axis of rotation is oriented downward when traversing the second axis of rotation from the rear of the foot towards the front of the user's foot, when the user is standing, in the anatomical reference position.

PRESENTATION OF THE DRAWINGS

Other characteristics and advantages will emerge from the following description, which is purely illustrative and non-limiting, and should be read in conjunction with the appended figures, among which:

- Figure 1 schematically shows, in front view, a user equipped with an exoskeleton structure according to one embodiment of the invention,

- Figure 2 shows schematically, in back view, part of the exoskeleton structure of Figure 1,

- Figure 3 schematically shows, in back view, part of the exoskeleton structure of Figure 1,

- Figure 4 shows schematically, in top view, part of the exoskeleton structure of Figure 1, and

- Figure 5 shows schematically, in side view, part of the exoskeleton structure of Figure 1.

DETAILED DESCRIPTION OF AN EMBODIMENT

FIG. 1 schematically represents a user standing on a horizontal floor, in an anatomical reference position (also called “reference position” or “standard anatomical position”) according to the reference system in anatomy.

Figure 1 also includes a diagram illustrating a frontal plane

F, a sagittal plane S and a transverse plane T of the user. In known manner, the sagittal plane S is defined as a plane parallel to the median plane which separates the left half from the right half of the user's body. The frontal plane F or coronal plane is defined as a plane perpendicular to the median plane and which separates the body into an anterior or ventral part and a posterior or dorsal part. The transverse plane T or transverse plane is defined as a plane perpendicular to the median plane and which separates the body into an upper part (on the side of the head) and a lower part (on the side of the feet).

In Figure 1, the user is equipped with an exoskeleton structure

1 effort assistance, to assist the user during movements of his lower limbs.

The exoskeleton structure 1 illustrated in FIG. 1 comprises a lumbar belt 2 suitable for surrounding the waist of the user, a first set of lower limbs 3 and a second set of lower limbs 4.

The lumbar belt 2 is arranged around the waist of the user, resting on the hips of the user. The kidney belt 2 can support a battery and a control unit (not shown) attached to the kidney belt. The battery is used to supply the various actuators of the structure with electrical energy. The control unit is programmed to control the various actuators.

The first lower limb set 3 extends along a user's first lower limb (in the example of Figure 1, the first lower limb set extends along the right lower limb of the user). user) and is connected to the lumbar belt 2 through a first hip pivot 31 (located to the right of the user).

The first set of lower limbs 3 comprises the first hip pivot 31, a first femoral part 32 adapted to extend along the user's right thigh, a first thigh part 33 adapted to be attached to the right thigh of the user, a first knee pivot 34, a first leg piece 35 suitable for being attached to the user's right leg, a first mechanical connecting assembly 36 and a first foot piece 37 suitable for being attached to the user's right foot.

The first hip pivot 31 allows rotation of the first femoral part 32 relative to the lumbar belt 2 during a flexion / extension movement of the user's right thigh relative to the pelvis.

The first set of lower limbs 3 may further comprise, integrated with the first hip pivot 31, a hip actuator comprising a stator and a rotor capable of being driven in rotation with respect to the stator in order to drive the tibial part 32 in rotation with respect to to the lumbar belt 2 during a flexion or extension movement of the right hip joint.

The first knee pivot 34 connects the first femoral part 32 to the first leg part 35. The knee pivot 34 allows rotation of the leg part 35 relative to the femoral part 32 during a flexion / extension movement. of the right knee joint.

The first lower limb assembly 3 may further comprise, integrated with the first knee pivot 34, a knee actuator comprising a stator and a rotor capable of being driven in rotation with respect to the stator to drive the leg piece 35 in rotation by relative to the femoral part 32 during a flexion or extension movement of the right knee joint.

As illustrated in Figure 2, the first link assembly 36 includes a pivot 361, a tibial piece 362, a pivot 363, an intermediate piece 364, and a pivot 365.

The tibial piece 362 extends along the user's calf, between the leg piece 35 and the intermediate piece 364. The tibial piece 362 has a first end 366 and a second end 367.

The leg piece 35 is connected to the tibial piece 362 through the pivot 361. More specifically, the leg piece 35 is connected to the first end 366 of the tibial piece 362 through the pivot 361. The pivot 361 allows rotation of the tibial piece 362 relative to the leg piece 35 about an axis of rotation X1, during an internal / external rotational movement of the user's foot relative to the leg.

The intermediate piece 364 extends between the tibial piece 362 and the foot piece 37. The intermediate piece 364 is connected to the tibial piece 362 through the pivot 363. More specifically, the intermediate piece 364 is connected to the second end. 367 of the tibial piece 362 through the pivot 363. The pivot 363 allows a rotation of the intermediate piece 364 relative to the tibial piece 362 about an axis of rotation X3, during a bending rotational movement / extension of the user's foot relative to the leg.

The intermediate piece 364 is connected to the foot piece 37 through the pivot 365. The pivot 365 is disposed behind the user's foot, that is to say behind the heel. The pivot 365 allows rotation of the foot piece 37 relative to the intermediate piece 364 about an axis of rotation X2, during a pronation / supination movement of the user's foot relative to the leg.

The foot piece 37 is suitable for being attached to the user's foot. More precisely, the foot piece 37 is suitable for being fixed to a right shoe 5 of the user, for example to the sole, so as to transfer the forces exerted on the exoskeleton structure 1 towards the ground via the shoe 5.

The foot piece 37 has two branches 371 and 372, able to extend on either side of the sole of the shoe 5. Each branch 371, 372 of the foot piece 37 is fixed to the sole, for example. by means of one or more fixing rods penetrating into the thickness of the sole.

The tibial piece 362 can be formed in two parts 368, 369 mounted to slide with respect to one another by means of a slide. The sliding of the parts 368 and 369 with respect to each other allows a shortening or an elongation of the tibial part 362 allowing the length of the tibial part 362 to be adjusted according to the morphology of the user. The tibial piece 362 may also include a locking device for locking the tibial piece to the desired length.

As can be seen in Figure 1, pivot 361 is disposed on one side of leg piece 35 such that leg piece 35 is between a user's sagittal plane S and pivot 361.

Further, the pivot 363 is disposed on one side of the user's foot, near the malleolus. More precisely, the pivot 363 is disposed on one side of the intermediate part 364, so that the intermediate part 364 is located between the sagittal plane S of the user and the pivot 363.

As a result, the tibial piece 362 extends over the outer side of the user's leg (and not in front of the tibia). This makes it possible to design a lightweight exoskeleton 1 structure. In addition, the exoskeleton structure 1 is easier to put on and take off. All the user has to do is put on or take off his shoe, as he would normally do, without the presence of the exoskeleton structure 1. Furthermore, this makes it possible to free up the space surrounding the ankle, and in particular the ankle. space located on the inner side of the ankle, so as to limit interference between the two sets of legs.

As illustrated in Figure 1, the second lower limb assembly 4 is symmetrical to the first lower limb assembly 3. The second lower limb assembly 4 is also connected to the kidney belt 2 through a second hip pivot 41. , symmetrical with the first hip pivot 31. The second set of

lower limb 4 extends along a second lower limb of the user (in the example of Figure 1, the second lower limb assembly extends along the left lower limb of the user).

The second lower limb assembly 4 comprises parts identical to those of the first lower limb assembly 3, but arranged symmetrically with respect to the sagittal plane S of the user.

Thus, the second set of lower limbs 4 comprises the second hip pivot 41, a second femoral part 42 suitable for extending along the left thigh of the user, a second thigh part 43 suitable for being fixed to the left thigh of the user, a second knee pivot 44, a second leg piece 45 suitable for being attached to the left leg of the user, a second mechanical connecting assembly 46 and a second foot piece 47 suitable for being attached to the user's left foot.

The second hip pivot 41 allows rotation of the second femoral part 42 relative to the lumbar belt 2 during a flexion / extension movement of the user's left thigh relative to the pelvis.

The second lower limb assembly 4 may further comprise a hip actuator, integrated with the hip pivot 41, comprising a stator and a rotor capable of being driven in rotation with respect to the stator in order to drive the tibial part 42 in rotation with respect to the lumbar belt 2 when flexing or extending the hip.

The second knee pivot 44 connects the second femoral part 42 to the second leg part 45. The knee pivot 44 allows rotation of the leg part 45 relative to the femoral part 42 during a flexion / extension movement. of the user's leg relative to the thigh.

The second lower limb assembly 4 may further include a knee actuator, integrated with the second knee pivot.

44, comprising a stator and a rotor suitable for being driven in rotation with respect to the stator in order to drive the leg piece 45 in rotation with respect to the femoral piece 42 during a movement of flexion or extension of the knee.

As illustrated in Figure 3, the second link assembly 46 comprises a first pivot 461, a tibial piece 462, a second pivot 463, an intermediate piece 464 and a third pivot 465.

The tibial piece 462 can be formed in two parts 468, 469 mounted to slide with respect to each other by means of a slide. The sliding of the parts 468 and 469 with respect to each other allows a shortening or an elongation of the tibial part 462 allowing the length of the tibial part 362 to be adjusted according to the morphology of the user. The tibial piece 462 may also include a locking device for locking the tibial piece to the desired length.

The second link assembly 46 is arranged symmetrically with the first link assembly 36, with respect to the sagittal plane S.

In particular, as can be seen in Figure 1, the first pivot 461 is disposed on one side of the leg piece 45 so that the leg piece 45 lies between a sagittal plane S of the user and the first pivot 461.

In addition, second pivot 463 is disposed on one side of the user's foot, near the malleolus. More precisely, the second pivot 463 is disposed on one side of the intermediate part 464, so that the intermediate part 464 is located between the sagittal plane S of the user and the second pivot 463.

As a result, the tibial piece 462 extends over the outer side of the user's leg (not in front of the tibia).

As illustrated in FIG. 2, the axis of rotation X1 of the pivot 361 is oriented so that it forms a first non-zero angle with respect to a vertical direction when the user is standing, in the anatomical reference position. The first angle a is between 1 and 30

degrees, preferably between 10 and 15 degrees, for example about 12 degrees.

Likewise, the axis of rotation X1 of the pivot 461 is also oriented so that it forms the same first non-zero angle a with respect to a vertical direction when the user is standing, in the anatomical reference position. .

Furthermore, as illustrated in Figures 2 and 3, the pivot 363 of the first link assembly 3 and the pivot 463 of the second link assembly 46 are arranged at a height less than the height of the user's malleoli when the user is standing.

The axis of rotation X3 is oriented so that it forms a non-zero angle b with a transverse plane T of the user when the user is standing, in the anatomical reference position, the angle being between 5 and 15 degrees, preferably between 6 and 8 degrees, for example about 8 degrees.

Further as illustrated in FIG. 4, the pivot 363 of the first link assembly 36 is disposed towards the rear of the user's foot relative to the user's malleolus. This arrangement makes it possible to minimize the dimensions of the intermediate part and consequently to make the exoskeleton structure lighter.

The pivot 463 of the second link assembly 46 has an arrangement symmetrical to that of the pivot 363 of the first link assembly 36 with respect to the sagittal plane.

In addition, the axis of rotation X3 is oriented so that it forms a non-zero angle y with a frontal plane F of the user when the user is standing, in the anatomical reference position, the angle being between 1 and 15 degrees, preferably between 4 and 7 degrees, for example about 6 degrees.

The axis of rotation X3 passes above the axis of rotation X2, without the axes of rotation X3 and X2 intersecting.

On the other hand, as illustrated in FIG. 4, both in the first link assembly 36 and in the second link assembly 46, the axis of rotation X1 intersects the axis of rotation X2.

As illustrated in Figure 5, the axis of rotation X2 is oriented at a non-zero angle d with a transverse plane T of the user when the user is standing, in the anatomical reference position, the angle being included between 1 and 30 degrees, preferably between 15 and 25 degrees, for example about 18 degrees.

The axis of rotation X2 is oriented downward when traversing the axis of rotation X2 from the rear of the foot to the front of the foot. This configuration has the advantage of providing enhanced stability of the exoskeleton structure 1, even when the user walks on uneven terrain, that is to say terrain exhibiting roughness. Indeed, if the user places his foot on a roughness, the point of application of the reaction force produced by the roughness on the sole of the shoe 6 will necessarily be above the pronation / supination axis X2, so that the resulting moment will tend to limit the rotation imposed on the user's ankle. (Conversely,

CLAIMS

1. Exoskeleton structure (1) comprising:

- a leg piece (35, 45) intended to be fixed to a user's leg,

- a foot piece (37, 47) intended to be fixed to a user's foot,

- a mechanical connecting assembly (36, 46) connecting the leg piece (35, 45) to the foot piece (37, 47), comprising a first pivot (361, 461) allowing rotation of the foot piece ( 37, 47) relative to the leg piece (35, 45) about a first axis of rotation (X1) during internal / external rotational movement of the user's foot, and a second pivot (365 , 465) allowing rotation of the foot piece (37, 47) relative to the leg piece (35, 45) about a second axis of rotation (X2) during an eversion / inversion movement of the user's ankle,

wherein the first pivot (361, 461) is arranged such that the first pivot (361, 461) is disposed on one side of the leg piece (35, 45), the leg piece (35, 45) is located between a sagittal plane of the user and the first pivot (361, 461), and the first pivot (361, 461) is located at a height greater than or equal to 20 centimeters from the ground when the user is standing , in the anatomical reference position, the first axis of rotation (X1) being oriented so that the distance between the first axis of rotation (X1) and the second axis of rotation (X2) is less than or equal to 5 centimeters.

2. Exoskeletal structure according to claim 1, wherein the first axis of rotation (X1) is oriented so that it intersects the second axis of rotation (X2).

3. Exoskeletal structure according to one of claims 1 and 2, wherein the first axis of rotation (X1) is oriented so that it forms a first non-zero angle (a) with respect to a vertical direction when the The user is standing in the anatomical reference position, the first angle being between 1 and 30 degrees, preferably between 10 and 15 degrees, for example equal to 12 degrees.

4. Exoskeleton structure according to one of claims 1 to 3, wherein the mechanical connecting assembly (36, 46) comprises a third pivot (363, 463) allowing rotation of the foot piece (37, 47 ) relative to the leg piece (35, 45) about a third axis of rotation (X3) during a flexion / extension movement of the user's ankle.

5. Exoskeletal structure according to claim 4, wherein the third pivot (363, 463) is arranged at a height less than the height of the user's malleolus when the user is standing, in the anatomical reference position. .

6. Exoskeleton structure according to one of claims 4 and 5, wherein the third pivot (363, 463) is arranged rearwardly of the user's foot relative to the user's malleolus.

7. Exoskeleton structure according to one of claims 4 to 6, wherein the first axis of rotation (X1) is oriented such that the distance between the first axis of rotation (X1) and the third axis of rotation (X3) ) is less than or equal to 5 centimeters.

8. Exoskeleton structure according to one of claims 4 to 7, wherein the third axis of rotation (X1) is oriented so that it intersects the third axis of rotation (X3).

9. Exoskeleton structure according to one of claims 4 to 8, wherein the third axis of rotation (X3) is oriented so that it forms a second non-zero angle (g) with a frontal plane of the user when the user is standing, in the anatomical reference position, the second angle being between 1 and 15 degrees, preferably between 4 and 7 degrees, for example equal to 6 degrees.

10. Exoskeleton structure according to one of claims 4 to 9, wherein the third axis of rotation (X3) is oriented so that it forms a third angle (b) non-zero with a transverse plane of the user when the user is standing, in the anatomical reference position, the angle being between 5 and 15 degrees, preferably between 6 and 8 degrees, for example equal to 8 degrees.

11. Exoskeleton structure according to one of claims 4 to 10, wherein the mechanical connecting assembly (36, 46) comprises a connecting piece (362, 462) having a first end (366, 466) connected to the leg piece (35, 45) via the first pivot (361, 461) and a second end (367, 467) connected to the third pivot (363, 463), the connecting piece (362, 462) comprising two parts ( 368, 369, 468, 469) slidably mounted relative to each other in order to adjust a length of the connecting piece (362, 462), and a locking device for locking the two parts (368, 369, 468, 469) relative to each other once the length has been set.

12. Exoskeleton structure according to one of claims 1-1 1, wherein the second axis of rotation (X2) is oriented so that it forms a fourth angle (d) non-zero relative to a horizontal direction when the user is standing, in the anatomical reference position, the angle being between 1 and 30 degrees, preferably between 15 and 25 degrees, for example 18 degrees.

13. Exoskeletal structure according to one of claims 1 to 12, wherein the second axis of rotation (X2) is oriented so that it passes below the malleolus of the user when the user is standing. , in the anatomical reference position.

14. Exoskeletal structure according to one of claims 1 to 13, wherein the second axis of rotation (X2) is oriented downward.

when traversing the second axis of rotation (X2) from the rear of the foot to the front of the user's foot, when the user is standing, in the anatomical reference position.