Robotic joint

Abstract

A robotic joint (1) configured to mutually rotate a first prosthesis (1a) and a second prosthesis (1b) and comprising: a first attachment (2) integral to the first prosthesis (1a); a second attachment (3) integral to the second prosthesis (1b); and a block (4) configured to define an axis of rotation (1c) reciprocal between the attachments (2, 3) and thus between the prostheses (1a, 1b); this block (4) includes a slider (41) constrained to the second attachment (3); and a first rail (42) defining a first angular sliding stroke of the slider (41); a second rail (43) defining a second angular sliding stroke of the slider (41); and a selector (47) configured to selectively engage the slider (41) to one of said rails (42, 43) by varying its stroke between said first angular stroke and said second angular stroke.

Description

[0001] DESCRIPTION

[0002] ROBOTIC JOINT

[0003] The present invention relates to a robotic joint of the type specified in the preamble to the first claim. Specifically, the invention relates to a joint capable of connecting two distinct mechanical elements together by allowing them to rotate towards each other. Such a joint can be used in the robotic field and, for example, in prosthetics and / or orthotics to simulate a joint such as a wrist.

[0004] As is known the ability to move a robotic limb and in particular a robotic arm in a humanlike manner, without penalizing its usability, is increasingly one of the most important goals. In particular, a particularly relevant challenge is to mimic, more efficiently and effectively, the movements of a robotic limb both when grasping an object and when moving the object. Therefore, over the years, numerous devices aimed at simulating hands (see for example EP3790513A1 , WO2017077429A1 , US2016166409A1 , WO2017199127A1 ,

[0005] WO0245918A1 ) and / or upper limbs (WO2023017351 A1 , US5549712A, WO9921517A1 , US4604098A) have been developed.

[0006] Numerous developments can also be identified relative to the lower limbs. Examples are described in WO2023 / 047256 US2013261766A1 , AU2010208020A1 , US2019175365A1 . More examples are described in CN106182067, WO2017169580 and CN115256452.

[0007] The prior art described comprises some important drawbacks.

[0008] In particular, in the known devices, special attention has been given to the reproduction of extensor muscles and their antagonists, i.e., the muscles that command the increase (extensor muscles) or decrease (antagonist muscles) of the angle formed between two parts of the body such as, for example, a pair of phalanges and thus of the hands or upper and lower limbs. This aspect led to the design of specific and complex joints for each individual movement / limb with the resulting complexity of design and implementation.

[0009] Another drawback thus lies in the fact that one therefore has the need to design joints for a left robotic arm distinct from those adopted for a right robotic arm even if used to perform the same functions. In fact, for example, a pair of robotic arms, although cooperating in the handling of an object, require the adoption of components and in particular joints with different mechanics.

[0010] Thus, an additional drawback is the high cost of production and assembly of the prior art joints.

[0011] Another drawback is the fact that there are basically no robotic joints capable of simulating a circumduction, i.e., a rotary motion of a limb around its own joint in which the limb describes in space a cone with the vertex placed in the joint on which it rotates, while the extremity, e.g., a hand or foot, traces a circumference / cylinder whose axis of rotation defines, in most cases, an extension of the barycentric axis of development prevailing in the static or rotating portion of the limb

[0012] In this situation, the technical task underlying this invention is to devise a robotic joint capable of substantially overcoming at least part of the aforementioned drawbacks.

[0013] Within the scope of said technical task, it is an important purpose of the invention to obtain a robotic joint easily adaptable to any application or working condition.

[0014] An imporant purpose of the invention is to have a robotic joint that is characterized by relatively simplified mechanics and allows for reduced manufacturing and assembly costs.

[0015] Another purpose of the invention is to make a robotic joint that allows for the control of a circumduction rotation and, preferably, is simple to control and operate and, at the same time, easy to construct and low in cost.

[0016] The technical task and the specified aims are achieved by a robotic joint as claimed in the annexed claim 1. Examples of preferred embodiment are described in the dependent claims.

[0017] The characteristics and advantages of the invention are clarified below by the detailed description of preferred embodiments of the invention, with reference to the accompanying figures, in which:

[0018] Fig. 1 shows a perspective view, to scale, of a robotic joint according to the invention joining a first prosthesis to a second prosthesis;

[0019] Figs. 2a-2b show a cross-section view, to scale, of a robotic joint assembly according to the invention in two different configurations;

[0020] Figs. 3a-3d display a cross-section view, to scale, of a sequence of using a different assembly than the one in Figs. 2a and 2b; and

[0021] Figs. 4a-4b illustrate a cross-sectional view, to scale, of a distinct detail of the robotic joint according to the invention.

[0022] In this document, when measurements, values, shapes, and geometric references (such as perpendicularity and parallelism) are associated with words like "approximately" or other similar terms, such as "almost" or "substantially", they are to be understood as excluding measurement errors or inaccuracies due to production and / or manufacturing errors and, above all, as having less than a slight deviation from the associated value, measurement, shape, or geometric reference. For example, if associated with a value, such terms preferably indicate a divergence of no more than 10% of the value itself.

[0023] Furthermore, when terms such as “first”, “second”, “upper”, “lower”, “main”, and “secondary” are used, they do not necessarily identify an order, relationship priority, or relative position, but they can simply be used to distinguish different components more clearly from one another.

[0024] Unless otherwise indicated, "perpendicular”, "transverse”, "parallel”, or "normal”, or other terms of geometric positioning between geometric elements (e.g., axes, directions, and straight lines) are to be understood with reference to their mutual geometric position between corresponding projections. Said projections are defined on a single plane parallel to the lying plane(s) of said geometric elements.

[0025] The measurements and data reported in this text are to be considered, unless otherwise indicated, as performed in the International Standard Atmosphere ICAO (ISO 2533:1975).

[0026] Unless otherwise specified, as reflected in the following discussions, terms such as "processing", "computing", "determination", "calculation", or the like are considered to refer to the action and / or processes of a computer or similar electronic computing device that manipulates and / or transforms data represented as physical, such as electronic quantities of records of a computer plant and / or memories, into other data similarly represented as physical quantities within computer plants, records, or other information storage, transmission, or display devices.

[0027] With reference to the figures, the robotic joint according to the invention is globally indicated with the number 1.

[0028] It identifies a joint configured to connect a first prosthesis 1a and a second prosthesis 1 b to each other by allowing them to rotate around an axis of rotation 1c. For example, in a possible nonlimiting application, robotic joint 1 is configured to allow mutual circumduction between first prosthesis 1 a and second prosthesis 1 b of at least a predefined angular stroke.

[0029] Specifically, it allows a rotation between first prosthesis 1 a and second prosthesis 1 b of a first angular stroke and a second angular stroke, distinct from said first stroke, so that, for example, the same joint can be used to be integrated into, say, a left or right joint.

[0030] The first stroke and the second stroke identify an angular extension having a point on the axis of rotation 1c as its center of rotation. They have at least partly non-overlapping areas along a radial direction to said axis 1c.

[0031] Said first stroke and said second stroke can have distinct angular extension. Preferably, they have the same angular extent.

[0032] Preferably, robotic joint 1 can be integrated into a joint such as an elbow, shoulder, or hip. In detail, the invention can also introduce a prosthetic system comprising first prosthesis 1 a; second prosthesis 1 b and a joint 1 binding first prosthesis 1 a and second prosthesis 1 b together.

[0033] The first prosthesis 1 a may be a robotic limb. Said robotic limb can be a lower limb (e.g. a leg and / or foot) or an upper limb such as a forearm or hand.

[0034] The second prosthesis 1 b can be identified as a torso or a limb (particularly a portion of a lower limb such as a thigh or an upper limb such as an arm). In some, the second prosthesis 1 b may be a prosthetic socket.

[0035] Robotic joint 1 includes a first attachment 2 of joint 1 to the first prosthesis 1 a; a second attachment 3 of joint 1 to the second prosthesis 1 b; and a block 4 configured to define said axis of mutual rotation 1 c between prostheses 1 a and 1 b and particularly between first attachment 2 and second attachment 3.

[0036] The first attachment 2 can be integrally constrained to the first prosthesis 1 a. Said constraint can be done in a known way and therefore is not further described.

[0037] It may include and in particular consist of a first flange binding to the first prosthesis 1 a.

[0038] The second attachment 3 can be integrally constrained to the second prosthesis 1 b. Said constraint can be done in a known way and therefore is not further described.

[0039] It may include and in particular consist of a second flange binding to the second prosthesis 1 b.

[0040] Block 4 is configured to mutually engage the two attachments 2 and 3 by allowing between them a rotation about the axis of rotation 1c of at least one predefined angular stroke. Specifically, it allows a rotation about the axis of rotation 1 c between attachments 2 and 3 and thus between prostheses 1 a and 1 b of said first angular stroke and said second angular stroke.

[0041] Block 4 includes a slider 41 bound to the second attachment 3; a first rail 42 of said slider 41 ; and a second rail 43 of said slider 41 . Preferably block 4 includes only one slider 41 ; only one first rail 42; and only one second rail 43.

[0042] The slider 41 is constrained to the second attachment 3 by defining only one degree of freedom with respect to the second attachment 3. To be precise, it is capable of exclusively translating with respect to the second attachment 3 along a direction parallel to the axis of rotation 1 c (i.e., along the sliding axis 4d mentioned below)

[0043] The first rail 42 is obtained on the first attachment 2 conveniently at a first surface facing, and in view of, the second attachment 3. In detail it can be obtained on the first flange on the opposite side of said first prosthesis 1 a when bound to the first attachment 2.

[0044] It develops for a first angular stroke along a first circular trajectory 4a developing around said axis of rotation 1c. Accordingly, the first rail 42 defines for the slider 41 a first sliding path developing along a first circular trajectory 4a having its center at a point on the axis of rotation 1 c.

[0045] The first trajectory 4a and then the first rail 42 are developed along a first plane perpendicular to the axis of rotation 1c.

[0046] The first trajectory 4a is barycentric to the first rail 42.

[0047] It defines with respect to the axis of rotation 1c a first radius. Said first radius can be between 2 cm and 100 cm.

[0048] The angular extension of the first angular stroke is preferably less than 360°. It may, for example, be between 15° and 160°.

[0049] The first rail 42 may include a first track 421 defining the first trajectory 4a; and a first stop 422 and an additional first stop 423 configured to limit the travel of slider 41 along the first track 421 to said first angular stroke. As a result, when committed to the first rail 42 the slider 41 slides between the first stops 422 and 423.

[0050] The first rail 42 and particularly the first track 421 can be identified as a ditch, carved out on the first attachment 2, circular whose bottom is carved out on the first attachment 2 and whose open section (i.e., the surface opposite said bottom) faces the second attachment 3. The second rail 43 is obtained on the first attachment 2 conveniently at a first surface facing, and in view of, the second attachment 3. In detail it can be obtained on the first flange on the opposite side of said first prosthesis 1 a when bound to the first attachment 2.

[0051] Preferably, the two rails 42 and 43 are cut out on the same surface as the first attachment 2.

[0052] The second rail 43 develops for a second angular stroke along a second circular trajectory 4b developing around said axis of rotation 1 c. Accordingly, the second rail 43 defines for the slider 41 a second sliding path developing along a second circular trajectory 4b having its center at a point on the axis of rotation 1c.

[0053] The second trajectory 4b and then the second rail 43 are developed along a second plane perpendicular to the axis of rotation 1c. Said second floor is preferably substantially coincident with the first floor.

[0054] The second trajectory 4b is barycentric to the second rail 43.

[0055] It defines with respect to the axis of rotation 1c a second radius.

[0056] Said second radius can be between 2 cm and 100 cm.

[0057] Preferably first and second radiuses have the same length. Consequently, trajectories 4a and 4b lie on the same circumference with center on axis of rotation 1 c,

[0058] The angular extension of the first angular stroke is preferably less than 360°. It may, for example, be between 15° and 160°.

[0059] Optionally, the first angular stroke is essentially the same as the second angular stroke. Preferably said first angular stroke and said second angular stroke and then said first rail 42 and said second rail 43 are specular with respect to a plane of symmetry on which the axis of rotation 1 c lies.

[0060] The second rail 43 may include a second track 431 defining the second trajectory 4b; and a second stop 432 and an additional second stop 433 configured to limit the travel of slider 41 along the second track 431 to said second angular stroke. As a result, when committed to the second rail 43 the slider 41 slides between the second stops 432 and 433.

[0061] The second rail 43 and in particular the second track 431 can be identified as a ditch, carved out on the first attachment 2, circular with the bottom on the first attachment 2 and open section facing the second attachment 3.

[0062] In some cases, block 4 includes a channel 44 made on the first attachment 2 appropriately at said first surface of the second attachment 3.

[0063] Channel 44 is circular having center in the axis of rotation 1 c. it can be identified as an annular ditch with bottom on the first attachment 2 and open section facing the second attachment 3. It has an angular extent approximately equal to the maximum value of the angular extent of said first stroke and said second stroke. Preferably, the angular width of channel 44 is substantially at least equal to the sum of the angular extensions of the first and second strokes and more preferably is equal to 360° (channel 44 is thus annular).

[0064] For example, it may encompass tracks 421 and 431 and to be precise include a ditch defining said tracks 421 and 431 . Specifically, first stops 422 and 423 delimit a first portion of channel 44 of slider 41 defining the first track 421 and thus the first angular stroke; and at the same time, second stops 432 and 433 delimit a second portion of channel 44 of slider 41 distinct from the first portion and defining the second track 431 and thus the second angular stroke.

[0065] In an initial non-limiting embodiment (Figs. 2a and 2b) rails 42 and 43 can be derived on separate portions of channel 44, i.e., non-part overlapping along a direction radial to axis of rotation 1 c. Consequently, first lines 422 and 423 delimit a portion of channel 44 distinct from that delimited by second lines 432 and 433.

[0066] In this first embodiment, the first stops 422 and 423 are integral to channel 44.

[0067] In this first embodiment, the second stops 432 and 433 are integral to channel 44.

[0068] In a second non-limiting embodiment (Figs. 3a-3d), rails 42 and 43, and thus the first and second strokes, can be, appropriately exclusively, partly overlapped along a direction radial to the axis of rotation 1c defining a portion of overlap. Consequently, when the first stops 422 and 423 are at maximum mutual distance they delimit a portion of channel 44 at least partially overlapping that delimited by the second stops 432 and 433 when also at maximum mutual distance. Preferably in this second embodiment, the first stop 422 and the second stop 432 are integral to channel 44; and the additional stops 423 and 433 are loosely constrained to channel 44 and preferably sliding in said channel 44. Specifically, block 4 may include a third rail 45 defining a third circular trajectory 4c developing around the axis of rotation 1 c; and a carriage 46 sliding along said third rail 45 and defining the additional stops 423 and 433. Specifically, carriage 46 defines supplementary stops 423 and 433 on opposite sides of the same carriage so that the supplementary first stop 423 faces the first stop 422 and the supplementary second stop 433 faces the second stop 432.

[0069] The third rail 45 develops for a third angular stroke along said third trajectory 4c. Said third angular stroke is essentially equal to the angular extent of said portion of the overlap.

[0070] The third trajectory 4c and then the third rail 45 are developed along a third plane perpendicular to the axis of rotation 1 c. In detail, the third plane can be basically coincident with the first and second plane.

[0071] Appropriately, the third rail 45 can identify a third portion of channel 44.

[0072] The third trajectory 4c and thus the third stroke can have an angular extent substantially equal to said portion of the overlap.

[0073] The third trajectory 4c defines with respect to the axis of rotation 1 c a third radius. Said third radius can be between 2 cm and 100 cm.

[0074] Preferably first and second radiuses have the same length. Consequently, trajectories 4a, 4b and 4c lie on the same circumference with center on axis of rotation 1c, Preferably, the third rail 45 identifies a corner sector of channel 44.

[0075] The third rail 45 may include a third track 451 defining the third trajectory 4c; and a third stop 452 and an additional third stop 453 configured to limit the carriage 46 travel along the third track 451 to said third angular stroke.

[0076] The additional third stop 453 may be proximal to the first stop 421 .

[0077] The third stop 452 may be proximal to the second stop 431 .

[0078] Carriage 46 defines a first position (Figs. 3a-3b), in which it is in contact with the third stop 452 and the distance between the first stops 422 and 423 is essentially equal to the first angular stroke; and a second position (Fig. 3d) in which it is in contact with the additional third stop 453 and the distance between the second stops 432 and 433 is basically equal to the second angular stroke.

[0079] In the first position, the distance between second stops 432 and 433 can be less than the second angular stroke.

[0080] In the second position, the distance between second stops 422 and 423 can be less than the first angular stroke.

[0081] Block 4 also includes a selector 47 (Figs. 4a and 4b) configured to selectively commit slider 41 to one of said rails 42, 43.

[0082] Accordingly, selector 47 defines, for joint 1 , a first configuration (Fig 4a) in which slider 41 is committed to the first rail 42; a second configuration (Fig 4a) in which slider 41 is committed to the second rail 43; and a third configuration (Fig 4b) in which slider 41 is committed to neither the first rail 42 nor the second rail 43.

[0083] In the first configuration, slider 41 is sliding in the first rail 42. Therefore, robotic joint 1 allows a rotation between attachments 2 and 3 and thus between prostheses 1 a and 1 b of maximum stroke equal to the first angular stroke.

[0084] In the second configuration, slider 41 is sliding in the second rail 43. Therefore, robotic joint 1 allows a rotation between attachments 2 and 3 and thus between prostheses 1 a and 1 b of maximum stroke equal to the second angular stroke.

[0085] In the third configuration, slider 41 is not associated with guides 42 and 43. Therefore, joint 1 allows rotation between connections 2 and 3 and without limitation of angular amplitude.

[0086] In the third configuration, slider 41 has a greater distance from the first attachment 2 than in the first and second configurations.

[0087] Selector 47 configured to move slider 41 with respect to rails 42 and 43 (optionally to channel 44 and then to third rail 45) along a slide axis 4d suitably transverse, and in detail approximately perpendicular, to trajectories 4a, 4b and optionally 4c. It, therefore, can allow the engagement and disengagement of slider 41 from rails 42 and 43 and in detail from channel 44 through the aforementioned open sections. Thus, slider 41 has a cross section smaller than the open sections of rails 42 and 43 and in detail of channel 44.

[0088] Selector 47 can be magnetic and thus configured to command the sliding of slider 41 along the sliding axis 4d. For this purpose it may comprise a spring 471 , appropriately preloaded, configured to press slider 41 toward rails 42 (i.e., in first or second configuration); a solenoid 472 configured to work in opposition to said spring and thus bring robotic joint 1 into third configuration; and appropriately powering means of said solenoid 472 configured to allow solenoid 472 to emit a magnetic field moving slider 41 away from rails 42 and 43.

[0089] Therefore, when joint 1 is in the first or second configuration, solenoid 472 is inactive, allowing spring 471 to press and thus engage slider 41 at rail 42 or 43; while in the third configuration, solenoid 472 is active and in particular defines a force greater than that of spring 471 by commanding the removal and thus disengagement of slider 41 from rails 42 and 43.

[0090] It is shown that slider 41 may be at least partly ferromagnetic so that solenoid 472 can move slider 41 .

[0091] Block 4 may also include a lock 48 to stop slider 41 at least when it is selectively in first or second configuration.

[0092] The lock 48 includes a first slot 481 integral with the second attachment 3; a second slot 482 integral with the slider 41 ; at least one rolling element 483 configured to selectively engage one of the slots 481 and 482; and a layer 484 interposed between said slots 481 and 482 and defining at least one housing cavity 484a for part of said at least one rolling element 483.

[0093] Preferably the lock 48 includes at least three rolling elements 483 suitably angled and equally spaced with respect to the sliding axis 4d.

[0094] The first slot 481 is annular of center the sliding axis 4d.

[0095] The second slot 482 is annular of center the sliding axis 4d.

[0096] The second slot 482 has a shorter distance (in detail a diameter) from the axis 4d than the first slot 481 .

[0097] Said at least one rolling element 483 has an axis of revolution perpendicular to the sliding axis 4d. It can be a sphere.

[0098] The layer 484 defines a cavity 484a for each rolling element 483. Alternatively, the layer 484 defines a single cavity 484a for the one or more rolling elements 483.

[0099] Said cavity 484a is a pass-through cavity and has a first open section proximal to the first slot 481 and a second open section proximal to the second slot 482.

[0100] Cavity 484a is configured to exclusively partially accommodate rolling element 483. As a result, each rolling element 483 protrudes from the cavity 484a (specifically from the layer 484) by inserting into the first slot 481 or the second slot 482.

[0101] Preferably, the rolling element 483 is housed, in addition to the cavity 484a, in the first slot 481 when the joint 1 is in first or second configuration blocking the sliding of the slider 41 (see enlargement of Fig. 4a); while it is housed in cavity 484a and second slot 482 when joint 1 is in the third configuration allowing slider 41 to slide (see enlargement of Fig. 4b).

[0102] Layer 484 is detachable with respect to second attachment 3, slider 41 , and selector 47 so that it can slide with respect to or together with them along the sliding axis 4d as better described below.

[0103] In addition, lock 48 includes a first rolling surface 485 integral with second attachment 3; a second rolling surface 486 integral with slider 41 .

[0104] The first rolling surface 485 is superimposed on the second slot 482 with respect to a direction normal to the axis 4d.

[0105] The first rolling surface 485 has a distance from the sliding axis 4d that is less than the diameter of the first slot 481 (the diameter of a slot is calculated at the point with the greatest distance from the axis 4d). Consequently, when joint 1 is in the third configuration the first rolling surface 485 maintains and in detail pushes the rolling element into the second slot 482.

[0106] The second rolling surface 486 is superimposed on the first slot 481 with respect to a direction normal to the axis 4d.

[0107] The second rolling surface 486 has a distance from the sliding axis 4d greater than the diameter of the second slot 482. Consequently, when joint 1 is in the first or second configuration the second rolling surface 486 maintains and in detail pushes the rolling element into the first slot 481 .

[0108] Robotic joint 1 may also include a motor, not shown for simplicity in the figure, configured to command a reciprocal rotation between attachments 2 and 3 and thus between prostheses 1 a and 1 b.

[0109] Accordingly, in the first configuration, the motor commands a rotation between attachments 2 and 3 thereby sliding slider 41 into the first rail 42 and, therefore, of maximum amplitude equal to said first stroke; in the second configuration, the motor commands a rotation between attachments 2 and 3 thereby sliding slider 41 into the second rail 43 and, therefore, of maximum amplitude equal to said second stroke; and in the third configuration, since slider 41 is not associated with rails 42 and 43, the motor commands a rotation between attachments 2 and 3 and with no limit on angular amplitude.

[0110] Preferably said motor is an electric motor.

[0111] In addition, robotic joint 1 may include a board to control the operation of the joint itself. The board can be configured to command selector 47 to switch to third configuration.

[0112] The board can be configured to command the motor to reciprocally rotate the attachments allowing, for example, switching between first and second configurations.

[0113] The invention may also introduce a robotic device comprising a first prosthesis 1 a, a second prosthesis 1 b, and a robotic joint 1 connecting said prostheses 1 a and 1 b to each other by allowing their mutual rotation about an axis of rotation 1c appropriately of amplitude selectively selected between a first angular stroke and a second angular stroke

[0114] The operation of robotic joint 1 previously described in structural terms is as follows. Specifically, this operation defines a new process for moving a robotic joint 1 and thus the prostheses 1 a and 1 b associated with it.

[0115] The process includes an installation phase in which the first prosthesis 1 a is constrained to robotic joint 1 at first attachment 2 and the second prosthesis 1 b is constrained to joint 1 at second attachment 3.

[0116] The process includes an initial operation phase in which slider 41 is engaged at first rail 42 or second rail 43, and then first attachment 2 (i.e., first prosthesis 1 a) and second attachment s (i.e., second prosthesis 1 b) can mutually rotate around axis of rotation 1c with a maximum amplitude equal to the first or second stroke, respectively. Said prostheses 1 a and 1 b thus perform a mutual rotation.

[0117] It is shown that at this stage of first operation each rolling element 483 is housed in the cavity 484a and the first slot 481 (Fig. 4a).

[0118] The process may include a transition phase wherein slider 41 is disengaged from one of rails 42 and 43 and then committed to the other of said rails 42 and 43.

[0119] The transition phase may include a disengagement subphase in which block 4 (in detail selector 47) disengages slider 41 from said one of said rails 42 and 43 (i.e., the transition to third configuration); a positioning subphase in which, while keeping slider 41 in that position, the two attachments 2 and 3 rotate with each other about the axis of rotation 1 c overlapping slider 41 to said other rail 42 and 43 appropriately along the sliding axis 4d; and finally an engagement subphase in which engagement block 47 engages slider 41 to said other rail 42 and 43.

[0120] In addition, during the transition phase the actuation of the selector 47 and thus the sliding of the slider 41 result in the movement along the sliding axis 4d of the layer 484 and thus of the one or more rolling elements 483.

[0121] Specifically, in the disengagement subphase the sliding of slider 41 commands the sliding of the second slot 482, which then occurs at the rolling element 483. As a result, the rolling element 483, no longer being pressed by the second surface 486 against the first slot 481 , translates radially to the sliding axis by arranging itself, in addition to the cavity 484a, in the second slot 482 thus escaping from the first slot 481 (Fig. 4b). Slider 41 arrives in the third configuration by sliding along the 4d axis and especially by dragging the layer 484 and the rolling element 483, which contacts the first sliding surface 485 by sliding on it in turn.

[0122] Similarly, in the engagement subphase the sliding of slider 41 (opposite to that of the disengagement phase) commands the sliding of the second slot 482 that drags the rolling element 483 and layer 484. When the rolling element 483 arises at the first slot 481 , no longer being pressed by the first sliding surface 485 toward the second slot 482, it translates radially to the sliding axis by arranging itself, in addition to the cavity 484a, in the first slot 481 thus escaping from the second slot 482 (Fig. 4a). Slider 41 thus gets stuck in first or second configuration.

[0123] At this point the procedure involves a second operation phase in which slider 41 is committed to a new rail 42 and 43 different from that of the first operation.

[0124] It is shown how, in the case of the above-mentioned second preferred embodiment, slider 41 , sliding along the new rail 42 and 43, commands the sliding of carriage 46 along the third rail 45 until carriage 46 comes into contact with one of the third stops 452 and 453.

[0125] In order to make the operation of the robotic joint 1 , and thus the handling procedure implemented by it, clearer, an application example is given with reference to the second embodiment shown above.

[0126] Suppose that, at the end of the installation phase, joint 1 is in first configuration and carriage 41 in first position (Fig. 4a).

[0127] Thus, during the first operation phase, the slider 41 is engaged, stably thanks to the grinding wheel of block 47, to the first rail 42, and thus the first attachment 2 (i.e., the first prosthesis 1 a) and the second attachment 3 (i.e., the second prosthesis 1 b) rotate reciprocally.

[0128] At this stage, prostheses 1 a and 1 b thus perform a mutual rotation of maximum amplitude equal to the first stroke.

[0129] At this point, the procedure may include a transition phase from the first configuration to the second, and thus, slider 41 is disengaged from the first rail 42 and committed to the second rail 43 (Fig. 4b). In detail, in the disengagement subphase, block 47 disengages slider 41 from the first rail 42 by bringing joint 1 from the first to the third configuration; in the next positioning subphase, while keeping robotic joint 1 in the third configuration, the two attachments 2 and 3 rotate mutually until slider 41 is superimposed (appropriately along the sliding axis 4d) on the second rail 43; finally, in the engagement subphase, engagement block 47 performs the transition from the third to the second configuration by engaging slider

[0130] 41 at the second rail 43.

[0131] At this point we have the second operation phase in which slider 41 is committed to the second rail 43 and thus robotic joint 1 is in the second configuration. In this configuration, as shown in Figs. 3c and 3d, the slider 41 , sliding in the second rail 43, contacts the supplementary second stop 433 and commands the sliding of the carriage 46 along the third rail 45 until the carriage 46 contacts the supplementary third stop 453 bringing the carriage 46 to the second position.

[0132] At this second operation stage, prostheses 1 a and 1 b perform a mutual rotation of maximum amplitude equal to the second stroke.

[0133] The robotic joint 1 and thus the handling procedure implemented by it according to the invention achieve important advantages.

[0134] In fact, robotic joint 1 identifies a device that is particularly simple to make and use, capable of simulating and then, in an approximately perfect manner, controlling a rotation between two prostheses 1 a and 1 b such as circumduction.

[0135] An important advantage is that robotic joint 1 is easily adaptable to any conditions of use. For example, due to the presence of two distinct so-called rails 42 and 43, it can be easily adapted to two distinct joints. In particular, at least in the case of the first stroke mirroring the second stroke, the same robotic joint 1 can be used for both a left joint (e.g., a left wrist or shoulder) and a right joint (e.g., a right wrist or shoulder).

[0136] Another advantage lies in the fact that the robotic joint 1 is simple in construction and therefore low in cost.

[0137] The invention can be modified to create different versions falling within the scope of the inventive concept defined by the claims. In this context, all the details can be replaced by equivalent elements and any materials, shapes and dimensions can be used.

Claims

CLAIMS1. Robotic joint (1) configured to reciprocally rotate a first prosthesis (1 a) and a second prosthesis (1 b) and comprising:- a first attachment (2) of said robotic joint (1 ) to said first prosthesis (1a);- a second attachment (3) of said robotic joint (1 ) to said second prosthesis (1 b);- a block (4) configured to define a reciprocal axis of rotation (1c) between said first attachment (2) and said second attachment (3) and thus between said prostheses (1a, 1 b); and characterized by the fact that said block (4) comprises- a slider (41 ) constrained to said second attachment (3);- a first rail (42) of said slider (41 ) o formed on said first attachment (2); and o defining for said slider (41 ) a first angular stroke along a first circular trajectory (4a) having axis on said axis of rotation (1c);- a second rail (43) of said slider (41) o formed on said first attachment (2); and o defining for said slider (41 ) a second angular stroke along a second circular trajectory (4b) having axis on said axis of rotation (1c);- selector (47) configured to selectively commit said slider (41 ) to one of said rail (42, 43) so that o when said slider (41 ) is engaged to said first rail (42) said robotic joint (1) allows a rotation between said attachments (2, 3) and thus between said prostheses (1 a, 1b) equal to said first angular stroke; and o when said slider (41 ) is engaged to said second rail (43) said robotic joint (1 ) allows a rotation between said attachments (2, 3) and hence between said prostheses (1 a, 1b) equal to said second angular stroke.

2. Robotic joint (1) according to claim 1 , wherein said first stroke and said secondstroke are mirrored with respect to a plane of symmetry on which lies said axis of rotation (1c).

3. Robotic joint (1 ) according to at least one preceding claim, wherein said first rail (42) comprising a first track (421 ) defining a first trajectory (4a) along which said slider (41 ) slides, and a first stop (422) and an additional first stop (423) configured to limit the travel of said slider (41 ) along said first track (421 ) defining said first angular stroke; and wherein said second rail (43) comprise a second track (431 ) defining a second trajectory (4b) along which said slider (41 ) runs, and a second stop (432) and an additional second stop (433) configured to limit the travel of said slider (41 ) along said second track (431 ) defining said second angular stroke; and wherein the radius of said first trajectory (4a) is substantially equal to the radius of said second trajectory.

4. Robotic joint (1 ) according to any preceding claim, wherein said block (4) comprises an annular channel (44) formed on said first attachment (2); wherein said first stops (422, 423) delineate a first portion of said channel (44) defining said first track (421 ); and wherein said second stops (432, 433) delineate a second portion of said channel (44) defining said first track (421 ) and distinct from said first portion.

5. Robotic joint (1 ) according to the preceding claim, wherein said first angular stroke and said second angular stroke and then said first rail (42) and said second rail (43) are partly overlapping along a radial direction to said axis of rotation (1 c) defining an overlapping portion; wherein said first stop (422) and said second stop (432) are integral with said channel (44); and wherein said block (4) includes a third rail (45) defining a third circular trajectory (4c) of said axis of rotation (1c) and a carriage (46) sliding along said third rail (45) relative to said channel (44) and defined said supplementary first stop (423) and said supplementary second stop (433).

6. Robotic joint (1 ) according to the preceding claim, wherein said third rail (45) comprising a third track (451 ) defining said third trajectory (4c); and a third stop (452) and an additional third stop (453) limiting the travel of said carriage (46) along said third track(451 ) defining a third angular stroke.

7. Robotic joint (1 ) according to the preceding claim, wherein said third angular stroke has an angular extension equal to the angular extension of said portion of the overlap between said first angular stroke and said second angular stroke.

8. Robotic joint (1 ) according to claim 4, wherein said first angular stroke and said second angular stroke, and hence said first rail (42) and said second rail (43) are not overlapping along a radial direction to said axis of rotation (1c); and wherein said stops (422, 423, 432, 433) are integral with said channel (44).

9. Robotic joint (1 ) according to the preceding claim, configured to permit reciprocal circumduction between said first prosthesis (1 a) and said second prosthesis (1 b).

10. Robotic device comprising a first prosthesis (1 a), a second prosthesis (1 b), and a robotic joint (1 ) according to at least one preceding claim.

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