Compact transmitter assembly, including the motor system, and including the active orthosis, active prosthesis, or exoskeleton

Abstract

The invention relates to a compact emitter assembly (2) configured to create a flow of driving fluid. The invention also relates to a driving system (1) comprising an emitter assembly (2) according to the invention, and a receiver assembly (3) configured to receive the flow of driving fluid and convert it into a stimulus. The invention also relates to an active orthosis, active prosthesis, or exoskeleton (4) comprising a driving system (1) according to the invention. Figure to be published: Figure 10

Description

Title of the invention: Compact transmitter assembly, motor system comprising it, and active orthosis or active prosthesis or exoskeleton comprising it

[0001] The present invention relates to the technical field of active orthoses, active prostheses and exoskeletons, and relates more particularly to a compact transmitter assembly, a motor system comprising it and an active orthosis or an active prosthesis or an exoskeleton comprising it.

[0002] Active orthoses, active prostheses or exoskeletons already exist which assist a user in the movement of a joint. These devices provide active assistance for the movement of a joint, for example an ankle, a knee or a hip, and in particular make it possible to overcome a motor disability in the case of active orthoses and active prostheses, or to increase the user's strength in the case of exoskeletons.

[0003] These devices generally comprise a motor assembly, or transmitter assembly, which can be arranged remotely, for example at the level of a backpack or a belt worn by the user, and an effector assembly, or receiver assembly, arranged close to the joint to be stressed, the motor assembly being configured to cause the effector assembly to stress said joint. Patent application FR3123204 A1 illustrates for example an existing device.

[0004] However, existing devices have certain drawbacks, including a large volume and a high mass for the motor assembly. Existing devices are therefore bulky, which makes them difficult to use because they are too heavy and bulky or stigmatizing for their users. For these reasons, user acceptance is still very limited for this type of device.

[0005] Therefore, the prior art solutions proposed for active orthoses, active prostheses or exoskeletons still have drawbacks and improvements are possible.

[0006] The present invention aims in particular to solve the problems indicated above by proposing a compact transmitter assembly, a motor system comprising it and an active orthosis or an active prosthesis or an exoskeleton comprising it.

[0007] Thus, the present invention relates to a compact transmitter assembly configured to create a flow of driving fluid for an active orthosis or an active prosthesis or an exoskeleton, characterized in that: the transmitter assembly comprises: an electric motor, comprising an output shaft extending along a first axis and rotated about the first axis, a transmission rod extending along a second axis, a transmission shaft extending along a second axis, a transmission shaft extending along a third axis, a transmission shaft extending along a fourth ... axis, rotatable about the second axis and rotated by the output shaft, and a master cylinder, comprising a body extending along the second axis and a piston movable by sliding in the body, the piston comprising a rod and defining in the body a rod-side chamber and a bottom-side chamber, each configured to, in use, be filled with working fluid; and the transmitter assembly is further configured such that: one of the transmission rod and the piston rod of the master cylinder carries an external thread extending from a distal end, the other of the transmission rod and the piston rod of the master cylinder comprises a recess extending along the second axis from a distal end and receiving an internal thread, a helical connection is formed between the external thread and the internal thread,such that rotation of the output shaft in a first rotational direction causes the master cylinder piston to slide in a first sliding direction, thereby reducing a volume of the rod-side chamber, expelling working fluid therefrom, and increasing a volume of the bottom-side chamber, drawing working fluid therein, and rotation of the output shaft in a second rotational direction, opposite the first rotational direction, causes the master cylinder piston to slide in a second sliding direction, opposite the first sliding direction, thereby reducing the volume of the bottom-side chamber, expelling working fluid therefrom, and increasing the volume of the rod-side chamber, drawing working fluid therein; and the master cylinder thereby creates the flow of working fluid, and the rod, among the transmission rod and the master cylinder piston rod,which carries the external thread enters at least partially into the recess when the output shaft is driven in the first direction of rotation and exits at least partially from the recess when the output shaft is driven in the second direction of rotation.

[0008] This configuration makes it possible to obtain a compact transmitter assembly, in particular by telescoping the transmission rod and the piston rod of the master cylinder.

[0009] For the purposes of the invention, the term "driving fluid" means hydraulic fluid, for example oil or another liquid, or pneumatic fluid, for example air or another gas.

[0010] According to one embodiment, the transmission rod carries the external thread and the transmitter assembly further comprises a guide rail and a guide part cooperating to guide the sliding of the piston of the master cylinder and to block a rotation of the piston of the master cylinder.

[0011] It will be understood that this configuration allows translational guidance of the piston of the master cylinder and prevents rotation of the piston of the master cylinder, which in particular allows friction between the piston and the body of the master cylinder to be reduced.

[0012] According to one embodiment, the transmitter assembly further comprises a threaded nut, a thread of the threaded nut defining at least a portion of the thread interior.

[0013] It will be understood that the remainder of the recess may have a cylindrical or square cross-section. It will also be understood that, alternatively, the recess could be entirely cylindrical and tapped to define the internal thread. In the case where the transmission rod carries the external thread and the master cylinder piston rod includes the recess, preferably, the distal end of the master cylinder piston rod includes a flange to which a threaded nut is attached, the diameter of the remainder of the master cylinder piston rod is constant along the entire length of the rod, and the recess is formed in the rod such that a portion of the rod in which the recess is formed can be received in the master cylinder body, depending on the sliding of the piston in the body. This configuration makes it possible to further reduce the volume required to receive the transmitter assembly.

[0014] According to one embodiment, the first axis coincides with the second axis, such that the output shaft, the transmission rod and the piston rod of the master cylinder are aligned, the transmission rod being integral with the output shaft.

[0015] This configuration makes it possible in particular to obtain a simple and compact structure for the transmitter assembly. It will be understood that the transmission rod can be secured to the output shaft by any means, for example by welding, or be formed in one piece with the output shaft. However, preferably, the transmission rod is secured to the output shaft by means of a flexible coupling, coupled both to the output shaft of the electric motor and to the transmission rod, in particular to ensure isostatic mounting.

[0016] According to one embodiment, the transmitter assembly further comprises a transmission mechanism, configured to transmit rotation between the output shaft and the transmission rod, comprising: a flexible coupling coupled to one end of the output shaft and rotatable about the first axis, a first toothed wheel, coupled to the flexible coupling and rotatably mounted about the first axis, a second toothed wheel, coupled to the transmission rod and rotatably mounted about the second axis, and a toothed belt, engaged with the first and second toothed wheels and configured to transmit rotation between the first and second toothed wheels.

[0017] It will be understood, however, that, according to variants, the first toothed wheel could directly mesh with the second toothed wheel, or the transmission mechanism could comprise one or more additional toothed wheels meshing between the first and second toothed wheels, or the first and second toothed wheels could be replaced by pulleys and the toothed belt could be replaced by a transmission belt in frictional engagement with the pulleys, or a cable or chain transmission could also be used.

[0018] According to one embodiment, the first axis and the second axis are distinct and pa rallèles, and the motor and the master cylinder are arranged on the same side of a median plane of the first toothed wheel perpendicular to the first and second axes.

[0019] This configuration makes it possible in particular to reduce the volume required to receive the transmitter assembly.

[0020] According to one embodiment, the transmitter assembly further comprises an elastic member configured to urge the piston of the master cylinder in the second sliding direction, over at least a portion of a sliding range of the piston of the master cylinder.

[0021] This configuration makes it possible in particular to reinforce the flow of driving fluid, and therefore to increase the induced stress, at the start of the sliding range of the piston of the master cylinder, without oversizing the transmitter assembly. This configuration is for example advantageous when the transmitter assembly is intended for an active orthosis or an active prosthesis or a knee exoskeleton and makes it possible in particular to facilitate the transition from a seated or squatting position to a standing position for the user. For example in a knee stress range of between 50° and 110°.The elastic member of the transmitter assembly may for example be a helical spring, or a tubular device compressing magnets in opposition of poles or a fluid (liquid or gas), or one or more tubes made of a material having elastic properties, for example a polymer, for example rubber, the material of the different tubes possibly being different to vary the stiffness over the stress range.

[0022] The present invention also relates to a motor system for an active orthosis or an active prosthesis or an exoskeleton characterized in that it comprises a transmitter assembly according to the invention and a receiver assembly configured to receive the flow of driving fluid coming from the transmitter assembly and convert it into a stress on the active orthosis or the active prosthesis or the exoskeleton, the receiver assembly comprising: a first slave cylinder, comprising a body and a piston movable by sliding in the body, the piston defining in the body a rod-side chamber, configured to, in use, be filled with driving fluid and fluidly connected to the rod-side chamber of the master cylinder, a second slave cylinder, comprising a body and a piston movable by sliding in the body, the piston defining in the body a rod-side chamber, configured to, in use,be filled with working fluid and fluidly connected to the bottom-side chamber of the master cylinder, at least one transmission element, a first end of the at least one transmission element being connected to a distal end of a piston rod of the first slave cylinder and a second end of the at least one transmission element being connected to a distal end of a piston rod of the second slave cylinder, and a rotation transmission member, engaged with the at least one element, transmission and configured to transform a stress of the at least one transmission element into a relative rotation, around a third axis and according to first and second opposite stress directions, of two fixing elements of the active orthosis or of the active prosthesis or of the exoskeleton intended to be respectively fixed to a user on either side of a joint to be stressed of which a pivot axis coincides with the third axis, the bodies of the first and second slave cylinders being configured to be secured to the same fixing element of the active orthosis or of the active prosthesis or of the exoskeleton;the motor system being further configured such that: rotation of the output shaft in the first rotational direction causes the master cylinder to introduce working fluid into the rod-side chamber of the first slave cylinder and to draw working fluid into the rod-side chamber of the second slave cylinder, causing the rotation transmission member to rotate in the first biasing direction, and rotation of the output shaft in the second rotational direction causes the master cylinder to introduce working fluid into the rod-side chamber of the second slave cylinder and to draw working fluid into the rod-side chamber of the first slave cylinder, causing the rotation transmission member to rotate in the second biasing direction. ;

[0023] This configuration makes it possible to transform the flow of driving fluid generated by the transmitter assembly into stress, in particular into torque around the third axis, for an active orthosis or an active prosthesis or an exoskeleton. Preferably, the first direction of stress corresponds to a flexion of the joint to be stressed, for example the knee, and the second direction of stress corresponds to an extension of the joint to be stressed, for example the knee. More preferably, the bodies of the first and second slave cylinders are arranged parallel to each other, such that the pistons of the first and second slave cylinders slide parallel to each other. This configuration makes it possible in particular to reduce the volume necessary to receive the receiver assembly.

[0024] According to one embodiment, the pistons of the first and second slave cylinders further define two respective bottom-side chambers, both configured to, in use, be filled with fluid and fluidly connected to each other by an elastically deformable conduit.

[0025] This configuration allows in particular a transfer of force between the first and second slave cylinders while avoiding cavitation in the chambers on the bottom side.

[0026] According to one embodiment, the receiver assembly further comprises an elastic member connected to the rotation transmission member and configured to bias the rotation transmission member in the second direction of biasing, over at least a portion of a rotation range of the rotation transmission member.

[0027] It will be understood that the elastic member of the receiving assembly has the same function than the elastic member of the transmitter assembly, in addition to or as a replacement for the latter. The elastic member of the receiver assembly may for example be a cylinder, for example arranged between the first and second slave cylinders, in which a spring is arranged, or magnets with opposing poles, or a fluid (liquid or gas), or an elastic material. According to another variant not shown, the elastic member may also be a torsion spring arranged at the level of the axis of rotation of the rotation transmission member.

[0028] According to one embodiment, the receiver assembly comprises one of: a single flexible transmission element having a first end connected to the distal end of the piston rod of the first slave cylinder and a second end connected to the distal end of the piston rod of the second slave cylinder, and a rotation transmission member comprising a cylinder-shaped portion in frictional engagement with the flexible transmission element; two transmission elements in the form of connecting rods, a first connecting rod having one end articulated to the distal end of the piston rod of the first slave cylinder and another opposite end articulated to the rotation transmission member, and a second connecting rod having one end articulated to the distal end of the piston rod of the second slave cylinder and another opposite end articulated to the rotation transmission member;two transmission elements in the form of toothed bars and a rotation transmission member comprising at least one toothed wheel, a first toothed bar having one end connected to the distal end of the piston rod of the first slave cylinder and another opposite end meshed with the rotation transmission member, and a second toothed bar having one end connected to the distal end of the piston rod of the second slave cylinder and another opposite end meshed with the rotation transmission member;and two flexible transmission elements, a first flexible transmission element having one end connected to the distal end of the piston rod of the first slave cylinder and another opposite end connected to the rotation transmission member, and a second flexible transmission element having one end connected to the distal end of the piston rod of the second slave cylinder and another opposite end connected to the rotation transmission member. ;

[0029] According to one embodiment, the receiver assembly comprises one of: a single flexible transmission element and a rotation transmission member comprising a cam-shaped portion, the flexible transmission element frictionally engaging the cam-shaped portion; and two flexible transmission elements and a rotation transmission member comprising two cylindrical, concentric elements of different diameters, a first flexible transmission element having one end connected to the distal end of the piston rod of the first slave cylinder and having another opposite end connected to a cylindrical element and partially wound thereon over at least a portion of a rotational range of the rotation transmission member, and a second flexible transmission element having one end connected to the distal end of the piston rod of the second slave cylinder and having another opposite end connected to the other cylindrical element and partially wound thereon over at least a portion of the rotational range of the rotation transmission member.

[0030] Preferably, for a cam-shaped portion, in the case where the joint to be stressed is a knee, a portion of the cam-shaped portion engaged with the flexible transmission element when the piston rod of the first slave cylinder applies traction to the cam-shaped portion has a radius smaller than a radius of a portion of the cam-shaped portion engaged with the flexible transmission element when the piston rod of the second slave cylinder applies traction to the cam-shaped portion.

[0031] Preferably, for two cylindrical elements, in the case where the joint to be stressed is a knee, the cylindrical element connected to the piston rod of the first slave cylinder by the first flexible transmission element has a radius less than a radius of the cylindrical element connected to the piston rod of the second slave cylinder by the second flexible transmission element.

[0032] According to the invention, the term "cam-shaped part" means a non-cylindrical part preferably having a first radius and a second radius. It will be understood that the cam-shaped part can be dimensioned to compensate for the asymmetry of the transmitter assembly, or alternatively to vary a torque applied to the joint to be stressed, according to the needs of the user. Furthermore, the term "flexible transmission element" means a non-stretchable flexible element capable of transmitting traction, for example, a cable, a belt, a toothed belt, a strap, a chain or a rope. It will also be understood that the frictional engagement of a flexible transmission element with the rotation transmission member can, where appropriate, be achieved by engaging teeth, or teeth and links, for example in the case of using a toothed belt or a chain.

[0033] According to one embodiment, the motor system is configured to maintain the same hydraulic reduction factor and is sized to comply with the equation below: [Math.l] Sfm _ stm St2xR2 Stïxm

[0034] with: Stm the annular cross-section of the chamber on the rod side of the master cylinder, Sfm the circular cross-section of the chamber on the bottom side of the master cylinder, Stl the annular cross-section of the chamber on the rod side of the first slave cylinder, St2 the annular cross-section of the rod-side chamber of the second slave cylinder, RI the radius of the cylindrical element on which the flexible transmission element connected to the piston rod of the first slave cylinder is partially wound, respectively the radius of the portion of the cam-shaped part engaged with the flexible transmission element when the piston rod of the first slave cylinder applies traction to the cam-shaped part, and R2 the radius of the cylindrical element on which the flexible transmission element connected to the piston rod of the second slave cylinder is partially wound, respectively the radius of the portion of the cam-shaped part engaged with the flexible transmission element when the piston rod of the second slave cylinder applies traction to the cam-shaped part.

[0035] It will be understood that this configuration allows a rotation of +x° of the output shaft in the first direction of rotation to cause the rotation transmission member to rotate by +y° in the first direction of stress and a rotation of -x° of the output shaft in the second direction of rotation to cause the rotation transmission member to rotate by -y° in the second direction of stress, which in particular makes it easier to control the motor system.

[0036] The present invention also relates to an active orthosis or an active prosthesis or an exoskeleton comprising two fixing elements intended to be respectively fixed to a user on either side of a joint to be stressed, characterized by the fact that the active orthosis or the active prosthesis or the exoskeleton further comprises a motor system according to the invention, the third pivot axis of which coincides with the pivot axis of said joint to be stressed, and a system for controlling the motor system.

[0037] The control system of the engine system may be, in particular, an electronic device, for example a processor, a microprocessor, a microcontroller, a digital signal processor (DSP), a field programmable gate array (FPGA), an application-specific integrated circuit (ASIC), comprising or associated with memory which contains instructions for controlling the engine system. The control system may also comprise inputs / outputs or even communication devices, wireless or wired.

[0038] Preferably, the transmitter assembly is arranged at a distance from the active orthosis or the active prosthesis or the exoskeleton, for example in a backpack or a belt worn by the user, and the receiver assembly is configured to be arranged at the level of the active orthosis or the active prosthesis or the exoskeleton, close to the joint to be stressed, by making the third pivot axis coincide with the pivot axis of said joint to be stressed.

[0039] It will be understood that the invention makes it possible in particular to overcome a motor handicap in the case of an active orthosis and an active prosthesis, or to increase the strength of the user in the case of an exoskeleton. The joint to be stressed can, for example, be a knee, an ankle, a hip, a wrist, a shoulder or an elbow. The attachment elements of the active orthosis or active prosthesis or the exoskeleton are designed to be fixed on either side of the desired joint. It will also be understood that the control of the electric motor also depends on the desired joint to be stressed.

[0040] In order to better illustrate the invention, several embodiments thereof will now be described, by way of illustration and not limitation, with reference to the appended drawings.

[0041] In these drawings:

[0042] [Fig-1] is a schematic representation of a motor system according to the invention.

[0043] [Fig.2] is a front perspective view of the compact transmitter assembly of [Fig. 1]

[0044] [Fig.3] is a rear perspective view of the compact transmitter assembly of the [Fig.2],

[0045] [Fig.4] is a sectional view of the compact transmitter assembly of [Fig.2].

[0046] [Fig.5] is a front perspective view of the receiver assembly of [Fig.l].

[0047] [Fig.6] is a rear perspective view of the receiver assembly of [Fig.5].

[0048] [Fig.7] is a sectional view of the receiver assembly of [Fig.5].

[0049] [Fig.8] is a schematic representation of a motor system according to a variant of the invention.

[0050] [Fig.9] is a schematic representation of an elastic member connected to the rotation transmission member, according to a variant of the present invention.

[0051] [Fig. 10] is a schematic representation of an active orthosis or an active prosthesis or an exoskeleton according to the invention.

[0052] [Fig. 11] is a schematic representation of a transmitter assembly according to a variant of the invention, for which the output shaft, the transmission rod and the piston rod of the master cylinder are aligned.

[0053] [Fig. 12a] is a schematic representation of a variant comprising a single flexible transmission element and a rotation transmission member with a cylinder-shaped portion.

[0054] [Fig. 12b] is a schematic representation of a variant comprising two transmission elements in the form of connecting rods.

[0055] [Fig. 12c] is a schematic representation of a variant comprising two transmission elements in the form of toothed bars and a rotation transmission member comprising a toothed wheel.

[0056] [Fig. 12d] is a schematic representation of a variant comprising two flexible transmission elements.

[0057] If we first refer to [Fig. 1], we can see that there is shown a motor system 1 according to the invention, comprising a compact transmitter assembly 2 and a receiver assembly 3 connected fluidically.

[0058] The motor system 1 is configured to generate stresses of an active orthosis or an active prosthesis or an exoskeleton 4. In particular, the transmitter assembly 2 is configured to create a flow of driving fluid, and the receiver assembly 3 is configured to receive the flow of driving fluid coming from the transmitter assembly 2 and convert it into stresses of the active orthosis or the active prosthesis or the exoskeleton 4. For the purposes of the invention, the term “driving fluid” means hydraulic fluid, for example oil or another liquid, or pneumatic fluid, for example air or another gas.

[0059] As schematically shown in [Fig. 10], the transmitter assembly 2 is preferably arranged at a distance from the active orthosis or the active prosthesis or the exoskeleton 4, for example in a backpack or a belt worn by the user, and the receiver assembly 3 is configured to be arranged at the level of the active orthosis or the active prosthesis or the exoskeleton 4, close to the joint to be stressed. A control system C, schematically shown in the backpack, makes it possible to control the assembly. The control system C of the motor system 1 may in particular be an electronic device, for example a processor, a microprocessor, a microcontroller, a digital signal processor (DSP), a field programmable gate array (FPGA), an application-specific integrated circuit (ASIC), comprising or associated with memory which contains instructions for controlling the motor system 1.The C control system can also include inputs / outputs or even communication devices, wireless or wired.

[0060] Figures 2 to 4 represent a transmitter assembly 2 according to the invention, comprising an electric motor 21, a transmission rod 221 and a master cylinder 23.

[0061] The electric motor 21 comprises an output shaft 211 extending along a first axis and rotated about the first axis by the electric motor 21.

[0062] The transmission rod 221 extends along a second axis and is rotatable about the second axis. As will be described in more detail below, the transmitter assembly 2 is further configured such that the transmission rod 221 is rotated by the output shaft 211 of the electric motor 21.

[0063] The electric motor 21 is preferably powered by an on-board battery and controlled by an on-board control system C, depending on the desired loads.

[0064] According to the embodiment shown in Figures 2 to 4, the transmitter assembly 2 further comprises a transmission mechanism 22 configured to transmit a rotation between the output shaft 211 and the transmission rod 221. The transmission mechanism 22 comprises a flexible coupling 222, a first toothed wheel 223, a second toothed wheel 224 and a toothed belt 225. The first toothed wheel 223 is rotatably mounted about the first axis, and the second toothed wheel 224 is rotatably mounted about the second axis, opposite the first toothed wheel 223. The first and second toothed wheels 223, 224 may for example be rotatably mounted using ball bearings as shown in [Fig. 4]. It will be understood, however, that other solutions are possible as a variant, for example the use of roller bearings, needle bearings or plain bearings. The flexible coupling 222 is coupled both to one end of the output shaft 211 of the electric motor 21 and to the first toothed wheel 223, and in particular makes it possible to ensure isostatic mounting of the motor system 1.According to a non-preferred variant, the output shaft 211 of the electric motor 21 could be directly coupled to the first toothed wheel 223. The second toothed wheel 224 is coupled to the transmission rod 221. The toothed belt 225 is arranged in engagement with both the first and second toothed wheels 223, 224 and is configured to transmit rotation between the first and second toothed wheels 223, 224. Preferably, the transmission mechanism 22 further comprises a tensioner roller 226 configured to tension the toothed belt 225 on the first and second toothed wheels 223, 224.

[0065] It will be understood that other configurations are possible for the transmission mechanism 22. For example, the first gear 223 could directly mesh with the second gear 224, or the transmission mechanism 22 could include one or more additional gears meshing between the first and second gears 223, 224, or the first and second gears 223, 224 could be replaced by pulleys and the toothed belt 225 could be replaced by a transmission belt in frictional engagement with the pulleys.

[0066] The master cylinder 23 comprises a body 231 extending along the second axis and a piston 232 movable by sliding in the body 231. The piston 232 comprises a rod 233 and defines, in the body 231, a rod-side chamber 234 and a bottom-side chamber 235, both configured to, in use, be filled with working fluid.

[0067] According to the embodiment shown in Figures 2 to 4, the transmission rod 221 carries an external thread extending from a distal end thereof, and the rod 233 of the piston 232 of the master cylinder 23 comprises a recess 24 extending along the second axis from a distal end of the rod 233, the recess 24 receiving an internal thread (tapping).

[0068] Diameters of the transmission rod 221 and of the recess 24, and pitches of the internal and external threads are chosen such that the distal end of the transmission rod 221 is inserted into the recess 24 and that a helical connection is formed between the external thread and the internal thread, such that a rotation of the transmission rod 221 causes a translation of the piston 232 in the body 231, and vice versa.

[0069] Thus, a rotation of the output shaft 211 in a first direction of rotation causes the piston 232 of the master cylinder 23 to slide in a first sliding direction, which reduces a volume of the rod-side chamber 234, expelling working fluid therefrom, and increases a volume of the bottom-side chamber 235, sucking working fluid therein, and a rotation of the output shaft 211 in a second direction of rotation, opposite to the first direction of rotation, causes the piston 232 of the master cylinder 23 to slide in a second sliding direction, opposite to the first sliding direction, which reduces the volume of the bottom-side chamber 235, expelling working fluid therefrom, and increases the volume of the rod-side chamber 234, sucking working fluid therein, such that the master cylinder 23 creates the flow of working fluid as a function of rotations of the output shaft 211 of the electric motor 21.

[0070] It will be understood that due to the helical connection, the transmission rod 221 penetrates at least partially into the recess 24 when the output shaft 211 is driven in the first direction of rotation and exits at least partially from the recess 24 when the output shaft 211 is driven in the second direction of rotation, which in particular makes it possible to reduce the volume necessary to receive the transmitter assembly 2.

[0071] According to the embodiment shown in Figures 1 to 4, the distal end of the rod 233 of the piston 232 of the master cylinder 23 comprises a flange to which a threaded nut 25 is fixed, the diameter of the remainder of the rod 233 of the piston 232 of the master cylinder 23 is constant over the entire length of the rod 233, and the recess 24 is formed in the rod 233 such that a portion of the rod 233 in which the recess 24 is formed can be received in the body 231 of the master cylinder 23, depending on the sliding of the piston 232 in the body 231. This configuration makes it possible to further reduce the volume necessary to receive the transmitter assembly 2.

[0072] According to a variant of the embodiment shown in Figures 2 to 4, the rod 233 of the piston 232 of the master cylinder 23 could carry the external thread extending from the distal end thereof, and the transmission rod 221 could comprise the recess 24 extending along the second axis from the distal end thereof, the recess 24 receiving the internal thread.

[0073] It will then be understood that the diameters of the rod 233 of the piston 232 of the master cylinder 23 and of the recess 24, and the pitches of the internal and external threads are chosen such that the distal end of the rod 233 of the piston 232 of the master cylinder 23 is inserted into the recess 24 and that a helical connection is formed between the thread external and internal thread, such that a rotation of the transmission rod 221 causes a translation of the piston 232 in the body 231, and vice versa.

[0074] It will also be understood that due to the helical connection, the rod 233 of the piston 232 of the master cylinder 23 penetrates at least partially into the recess 24 when the output shaft 211 is driven in the first direction of rotation and exits at least partially from the recess 24 when the output shaft 211 is driven in the second direction of rotation, which in particular makes it possible to reduce the volume necessary to receive the transmitter assembly 2.

[0075] According to the embodiment shown in Figures 2 to 4, the internal thread is defined by the tapping of the threaded nut 25 disposed at the distal end of the rod 233 of the piston 232 of the master cylinder 23. It will be understood that the remainder of the recess 24 may have a cylindrical or square cross-section. However, according to a variant, the recess 24 could be entirely cylindrical and tapped to define the internal thread.

[0076] It will be understood that, similarly, for the variant mentioned above for which the rod 233 of the piston 232 of the master cylinder 23 carries the external thread, the internal thread can be defined by the tapping of a threaded nut 25 arranged at a distal end of the transmission rod 221. It will also be understood that in a limiting case of this variant, the transmission rod 221 could consist solely of a threaded nut 25 directly coupled to the second toothed wheel 224, the threaded hole of the threaded nut 25 forming the recess 24. It will also be understood that, in this case, the second toothed wheel 224 further comprises a central recess, formed in correspondence with the threaded nut 25, configured to allow the rod 233 of the piston 232 of the master cylinder 23 to pass through the second toothed wheel 224 as a function of the translations of the piston 232 in the body 231.

[0077] According to the embodiment shown in Figures 2 to 4, the transmitter assembly 2 further comprises an elastic member 26 arranged around the transmission rod 221 and configured to urge the piston 232 of the master cylinder 23 in the second sliding direction, at the start of a sliding range of the piston 232 of the master cylinder 23. This configuration makes it possible in particular to increase the induced stress, generated by the motor system 1, at the start of the sliding range of the piston 232 of the master cylinder 23, without oversizing the transmitter assembly 2. This configuration is for example advantageous when the motor system 1 is configured to generate stresses at the level of a knee of the user and makes it possible in particular to facilitate the transition from a seated or squatting position to a standing position of the user. For example in a knee stress range of between 50° and 110°.

[0078] According to a variant, the elastic member 26 could also be arranged around the rod 233 of the piston 232 of the master cylinder 23, inside the chamber on the rod side 234 of the cylinder. master cylinder 23, to obtain the same stressing effect over the range 50 to 110°. According to another variant, the elastic member 26 can be configured to stress the piston 232 of the master cylinder 23 in the second sliding direction over the entire sliding range of the piston 232 of the master cylinder 23.

[0079] It will be understood that the elastic member 26 is compressed during a movement of the piston 232 of the master cylinder 23 in the first sliding direction and then applies an elastic return force to the piston 232 of the master cylinder 23 in the second sliding direction.

[0080] The elastic member 26 may for example be a helical spring, as shown in Figures 2 to 4, or one or more tubes made of a material having elastic properties, for example a polymer, for example rubber, the material of the different tubes possibly being different to vary the stiffness over the stress range.

[0081] According to the embodiment shown in Figures 2 to 4, the transmitter assembly 2 further comprises a frame 27 on which the electric motor 21, the transmission mechanism 22 and the body 231 of the master cylinder 23 are mounted. Preferably, the frame 27 comprises a guide rail 28, and the distal end of the rod 233 of the piston 232 of the master cylinder 23 carries a guide piece 29 configured to slide in the guide rail 28, the guide rail 28 and the guide piece 29 cooperating to guide a sliding of the piston 232 of the master cylinder 23 and prevent a rotation of the piston 232 of the master cylinder 23 in the body 231. It will be understood that, in the case of the variant mentioned above for which the external thread is carried by the rod 233 of the piston 232 of the master cylinder 23, another system may be used to prevent rotation of the piston 232 in the body 231.For example, the piston 232 can carry a bar extending parallel to the rod 233 and guided in sliding by a sleeve secured to the frame 27.

[0082] As shown in Figures 2 to 4, the first axis and the second axis are preferably distinct and parallel, and the motor 21 and the master cylinder 23 are arranged on the same side of a median plane of the first toothed wheel 223 perpendicular to the first and second axes. This configuration makes it possible in particular to reduce the volume necessary to receive the transmitter assembly 2.

[0083] Furthermore, [Fig. 11] schematically represents a transmitter assembly 2 according to a variant of the embodiment shown in Figures 2 to 4, for which the first axis coincides with the second axis, such that the output shaft 211, the transmission rod 221 and the rod 233 of the piston 232 of the master cylinder 23 are aligned. According to this variant, the transmission rod 221 is integral with the output shaft 211. It will be understood that the transmission rod 221 can be integral with the output shaft 211 by any means, for example by welding, or be formed in one piece with the output shaft 211. However, preferably, the transmission rod 221 is secured to the output shaft 211 by means of a flexible coupling 222, coupled both to the output shaft 211 of the electric motor 21 and to the transmission rod 221, in particular to ensure isostatic mounting of the motor system 1. It will also be understood that, in the case where the internal thread is obtained using a threaded nut 25, the means for securing the threaded nut 25 to the rod carrying the recess 24 can be configured to have degrees of flexibility and / or play and / or adjustment, in order to compensate for any misalignment between the internal thread and the external thread.

[0084] It will also be understood that a transmitter assembly 2 according to the variant shown schematically in [Fig. 1 1] can also comprise an elastic member 26, in a manner analogous to that described above.

[0085] Furthermore, in [Fig.l 1], the external thread is carried by the transmission rod 221, and the recess 24 and the internal thread are carried by the rod 233 of the piston 232 of the master cylinder 23. It will be understood, however, that this configuration can be reversed, in a manner analogous to that described above, that is to say that the external thread is carried by the rod 233 of the piston 232 of the master cylinder 23, and the recess 24 and the internal thread are carried by the transmission rod 221.

[0086] It will also be understood that for the variant shown in [Fig. 11], the helical links are formed in a manner analogous to that described above for the embodiment shown in Figures 2 to 4.

[0087] Figures 1, 5 to 7 represent a receiver assembly 3 according to the invention, comprising a first slave cylinder 31, a second slave cylinder 32, a transmission element 33 and a rotation transmission member 34.

[0088] As indicated above, the receiver assembly 3 is configured to be arranged, in use, at the level of the active orthosis or the active prosthesis or the exoskeleton 4 to be stressed, the active orthosis or the active prosthesis or the exoskeleton 4 comprising two fixing elements 41, 42 intended to be respectively fixed to the user on either side of a joint to be stressed, a pivot axis of which defines a third axis.

[0089] The first slave cylinder 31 comprises a body 311 and a piston 312 movable by sliding in the body 311. The piston 312 comprises a rod 313 and defines, in the body 311, a rod-side chamber 314 configured to, in use, be filled with working fluid and to be fluidly connected to the rod-side chamber 234 of the master cylinder 23.

[0090] The second slave cylinder 32 comprises a body 321 and a piston 322 movable by sliding in the body 321. The piston 322 comprises a rod 323 and defines, in the body 321, a rod-side chamber 324 configured to, in use, be filled with working fluid and be fluidically connected to the bottom side chamber 235 of the master cylinder 23.

[0091] The bodies 311, 321 of the first and second slave cylinders 31, 32 are configured to be secured to the same fixing element 41 of the active orthosis or the active prosthesis or the exoskeleton 4, for example by bolting, strapping or by hook and loop fixing. Preferably, the bodies 311, 321 of the first and second slave cylinders 31, 32 are arranged parallel to each other, such that the pistons 312, 322 of the first and second slave cylinders 31, 32 slide parallel to each other. This configuration makes it possible in particular to reduce the volume necessary to receive the receiver assembly 3.

[0092] The rotation transmission member 34 is configured to generate a relative rotation, around the third axis and in first and second opposite directions of stress, of the two fixing elements 41, 42 of the active orthosis or of the active prosthesis or of the exoskeleton 4. The mounting of the rotation transmission member 34 to the fixing elements 41, 42 will be described below.

[0093] According to the embodiment shown in Figures 5 to 7, the receiver assembly 3 comprises a single flexible transmission element 33 having a first end connected to a distal end of the rod 313 of the piston 312 of the first slave cylinder 31 and a second end connected to a distal end of the rod 323 of the piston 322 of the second slave cylinder 32, and the rotation transmission member 34 comprises a cam-shaped portion 341 in frictional engagement with the flexible transmission element 33, to transform a stress of the flexible transmission element 33 into a rotation of the rotation transmission member 34 and therefore into a relative rotation, around the third axis and in first and second opposite stress directions, of the two fixing elements 41, 42 of the active orthosis or the active prosthesis or the exoskeleton 4.The cam-shaped portion 341 is understood to mean a non-cylindrical portion preferably having a first radius and a second radius. As will be detailed below, the cam-shaped portion 341 may be sized to compensate for the asymmetry of the transmitter assembly 2, or alternatively to vary a torque applied to the joint to be stressed, according to the user's needs.

[0094] Preferably, in the case where the joint to be stressed is a knee, a portion of the cam-shaped part 341 engaged with the flexible transmission element 33 when the rod 313 of the piston 312 of the first slave cylinder 31 applies traction to the cam-shaped part 341 has a radius smaller than a radius of a portion of the cam-shaped part 341 engaged with the flexible transmission element 33 when the rod 323 of the piston 322 of the second slave cylinder 32 applies traction to the cam-shaped part 341.

[0095] It will be understood that other configurations are possible to transform the solli- citations of the first and second slave cylinders 31, 32 in rotation.

[0096] According to a variant, shown schematically in [Fig. 8], the receiver assembly 3 may comprise two flexible transmission elements 33 and a rotation transmission member 34 comprising two cylindrical elements 342, concentric and of different diameters. A first flexible transmission element 33 has one end connected to the distal end of the rod 313 of the piston 312 of the first slave cylinder 31 and has another opposite end connected to a cylindrical element 342 and partially wound thereon over a portion of a rotation range of the rotation transmission member 34. A second flexible transmission element 33 has one end connected to the distal end of the rod 323 of the piston 323 of the second slave cylinder 32 and has another opposite end connected to the other cylindrical element 342 and partially wound thereon over a portion of the rotation range of the rotation transmission member 34.

[0097] Preferably, in the case where the joint to be stressed is a knee, the cylindrical element 342 connected to the rod 313 of the piston 312 of the first slave cylinder 31 by the first flexible transmission element 33 has a radius smaller than a radius of the cylindrical element 342 connected to the rod 323 of the piston 322 of the second slave cylinder 32 by the second flexible transmission element 33.

[0098] According to another variant shown schematically in [Fig. 12a], the receiver assembly 3 could also comprise a single flexible transmission element 33 having a first end connected to the distal end of the rod 313 of the piston 312 of the first slave cylinder 31 and a second end connected to the distal end of the rod 323 of the piston 322 of the second slave cylinder 32, and a rotation transmission member 34 comprising a cylinder-shaped part in frictional engagement with the flexible transmission element 33.

[0099] According to another variant shown schematically in [Fig. 12b], the receiver assembly 3 could also comprise two rigid transmission elements 33, in the form of connecting rods, a first connecting rod having one end articulated to the distal end of the rod 313 of the piston 312 of the first slave cylinder 31 and another opposite end articulated to the rotation transmission member 34, and a second connecting rod having one end articulated to the distal end of the rod 323 of the piston 322 of the second slave cylinder 32 and another opposite end articulated to the rotation transmission member 34. The connecting rods can for example be articulated by the use of ball joints or pivot joints.

[0100] According to another variant shown schematically in [Fig.12c], the receiver assembly 3 could also comprise two rigid transmission elements 33, in the form of toothed bars, and a rotation transmission member 34 comprising one or more toothed wheels, a first toothed bar having one end connected to the distal end of the rod 313 of the piston 312 of the first slave cylinder 31 and another opposite end meshed with the rotation transmission member 34, and a second toothed bar having one end connected to the distal end of the rod 323 of the piston 322 of the second slave cylinder 32 and another opposite end meshed with the rotation transmission member 34. It will be understood that the choice of the number of toothed wheels of the rotation transmission member 34 makes it possible in particular to reverse the direction of rotation of the rotation transmission member 34.

[0101] Figures 12b and 12c show variants for which the chambers of the master cylinder 23 are intended to be connected to the bottom-side chambers 315, 325 of the first and second slave cylinders 31, 32. It will be understood, however, that as a variant, the chambers of the master cylinder 23 could be intended to be connected to the rod-side chambers 314, 324 of the first and second slave cylinders 31, 32, in a manner analogous to that described above.

[0102] According to another variant shown in [Fig.l2d], the receiver assembly 3 could also comprise two flexible transmission elements 33, a first flexible transmission element 33 having one end connected to the distal end of the rod 313 of the piston 312 of the first slave cylinder 31 and another opposite end connected to the rotation transmission member 34, and a second flexible transmission element 33 having one end connected to the distal end of the rod 323 of the piston 322 of the second slave cylinder 32 and another opposite end connected to the rotation transmission member 34.

[0103] According to the invention, the term flexible transmission element 33 is understood to mean a flexible element capable of transmitting traction, for example, a cable, a belt, a toothed belt, a strap, a chain or a rope. It will be understood that the frictional engagement of a flexible transmission element 33 with the rotation transmission member 34 may, where appropriate, be achieved by engaging teeth, or teeth and links, for example in the case of using a toothed belt or a chain.

[0104] Each flexible transmission element 33 may be fixed to the corresponding piston rod 313, 323 of the piston 312, 322 by any means, for example by gluing, bolting or form-fitting engagement, for example by engaging a ball integral with the flexible transmission element 33 with a slot formed in the corresponding piston rod 313, 323 of the piston 312, 322, or by securing to a sleeve and screwing the sleeve onto the distal end of the rod 313, 323, the latter solution in particular allowing fine adjustment of the length of the flexible transmission element 33 by screwing. Where appropriate, each flexible transmission element 33 may be fixed to the rotation transmission member 34 by any means, for example by gluing, bolting or form-fitting engagement, for example by example by engaging a ball integral with the flexible transmission element 33 with a slot formed in the rotation transmission member 34.

[0105] The motor system 1 is further configured such that rotation of the output shaft 211 in the first rotation direction causes the master cylinder 23 to introduce working fluid into the rod-side chamber 314 of the first slave cylinder 31 and to suck working fluid into the rod-side chamber 324 of the second slave cylinder 32, thereby causing the rotation transmission member 34 to rotate in the first biasing direction, and rotation of the output shaft 211 in the second rotation direction causes the master cylinder 23 to introduce working fluid into the rod-side chamber 324 of the second slave cylinder 32 and to suck working fluid into the rod-side chamber 314 of the first slave cylinder 31, thereby causing the rotation transmission member 34 to rotate in the second biasing direction.

[0106] In Figures 1 to 10, the first direction of stress corresponds to a flexion of the joint to be stressed, for example the knee in [Fig. 10], and the second direction of stress corresponds to an extension of the joint to be stressed, for example the knee in [Fig. 10].

[0107] As indicated above, the bodies 311, 321 of the first and second slave cylinders 31, 32 are configured to be secured to the same fixing element 41 of the active orthosis or of the active prosthesis or of the exoskeleton 4. Preferably, the receiver assembly 3 further comprises a frame 35 configured to be secured to a first of said fixing elements 41 and on which the rotation transmission member 34 is rotatably mounted, for example by the use of ball bearings, and the bodies 311, 321 of the first and second slave cylinders 31, 32 are fixedly mounted. The frame 35 preferably includes a length adjustment mechanism 36 configured to allow adjustment of the length of the receiver assembly 3 depending on the size of the user and the dimensions of the active orthosis or active prosthesis or exoskeleton 4.More preferably, the rotation transmission member 34 comprises a lever portion 343 configured to be secured to a second of said fixing elements 42, for example by bolting, strapping or by hook and loop fixing.

[0108] According to the embodiment shown in Figures 5 to 7, the pistons 312, 322 of the first and second slave cylinders 31, 32 define two respective bottom-side chambers 315, 325, both configured to, in use, be filled with fluid and fluidically connected to each other by an elastically deformable conduit 37. This configuration notably allows a transfer of force between the first and second slave cylinders 31, 32 while avoiding cavitation in the bottom-side chambers 315, 325.

[0109] According to a variant shown schematically in [Fig.9], the receiver assembly 3 may further comprise an elastic member 38 connected to the rotation transmission member 34 and configured to bias the rotation transmission member 34 in the second biasing direction, over at least a portion of a rotation range of the rotation transmission member. The elastic member 38 may for example be a cylinder, for example arranged between the first and second slave cylinders 31, 32, in which a spring is arranged, or magnets with opposing poles, or a fluid (liquid or gas), or an elastic material. [Fig. 12a] shows another variant for positioning the elastic member 38 around the rod 313 of the first slave cylinder 31. According to another variant not shown, the elastic member may also be a torsion spring arranged at the axis of rotation of the rotation transmission member 34.It will be understood that the elastic member 38 of the receiver assembly 3 has the same function as the elastic member 26 of the transmitter assembly 2, in addition to or as a replacement for the latter.

[0110] Due to the asymmetry of the chambers on the rod side 234 and the bottom side 235 of the master cylinder which creates the flow of working fluid, a rotation of +x° of the output shaft 211 in the first direction of rotation can cause the rotation transmission member 34 to rotate by +y° in the first direction of stress while a rotation of -x° of the output shaft 211 in the second direction of rotation can cause the rotation transmission member 34 to rotate by -z° in the second direction of stress, y being different from z.

[0111] In certain cases, this asymmetry of stress may correspond to the needs of the user or be compensated by the control system C of the motor system 1.

[0112] In other cases, for example to facilitate the control of the engine system 1, it is preferable for the engine system 1 to be configured to maintain the same hydraulic reduction factor, such that a rotation of +x° of the output shaft 211 in the first direction of rotation causes the rotation transmission member 34 to rotate by +y° in the first direction of stress and a rotation of -x° of the output shaft 211 in the second direction of rotation causes the rotation transmission member 34 to rotate by -y° in the second direction of stress. For the embodiment shown in [Fig.l] and the variant shown in [Fig.8], the engine system 1 is then dimensioned to comply with the equation below:

[0113] [Math.2] $fm _ Stm St2xR2 StlxRl (eq. 1)

[0114] with: Stm the annular cross-section of the rod-side chamber 234 of the master cylinder 23; Sfm the circular cross-section of the bottom-side chamber 235 of the master cylinder 23; Stl the annular cross-section of the rod-side chamber 314 of the first slave cylinder 31; St2 the annular cross-section of the rod-side chamber 324 of the second slave cylinder 32; RI the radius of the cylindrical element 342 on which the flexible transmission element 33 connected to the rod 313 of the piston 312 of the first slave cylinder 31 is partially wound, respectively the radius of the portion of the cam-shaped part 341 engaged with the flexible transmission element 33 when the rod 313 of the piston 312 of the first slave cylinder 31 applies traction to the cam-shaped part 341; and R2 the radius of the cylindrical element 342 on which the flexible transmission element 33 connected to the rod 323 of the piston 322 of the second slave cylinder 32 is partially wound, respectively the radius of the portion of the cam-shaped part 341 engaged with the flexible transmission element 33 when the rod 323 of the piston 322 of the second slave cylinder 32 applies traction to the cam-shaped part 341.

[0115] It will also be understood that the motor system 1 according to the invention can also be used to brake, or dampen, pivoting movements of the articulation around the third axis, by controlling the electric motor 21 to brake a movement of the piston 232 of the master cylinder 23 induced by a movement of the driving fluid generated by the first and second slave cylinders 31, 32 due to a movement of the articulation.

[0116] The invention also relates to an active orthosis or an active prosthesis or an exoskeleton 4 comprising two fixing elements 41, 42 intended to be respectively fixed to a user on either side of a joint to be stressed, and a motor system 1 according to the invention, the third pivot axis of which coincides with the pivot axis of said joint to be stressed. [Fig. 10] schematically shows an active orthosis or active prosthesis or exoskeleton 4 according to the invention worn by a user. It will be understood that the invention makes it possible in particular to overcome a motor handicap in the case of an active orthosis and an active prosthesis, or to increase the strength of the user in the case of an exoskeleton.

[0117] Although the joint to be stressed is a knee in the embodiment shown in [Fig. 10], it will also be understood that the joint to be stressed could be another joint, for example an ankle, a hip, a wrist, a shoulder or an elbow and that the fixing elements 41, 42 of the active orthosis or of the active prosthesis or of the exoskeleton 4 are then designed to be fixed on either side of the desired joint. It will also be understood that the control of the electric motor 21 by the control system C also depends on the desired joint to be stressed.

[0118] It is understood that the particular embodiments which have just been described have been given for informational and non-limiting purposes, and that modifications may be made without departing from the scope of the present invention.

Claims

Claims

1. Compact transmitter assembly (2) configured to create a flow of driving fluid for an active orthosis or an active prosthesis or an exoskeleton (4), characterized in that: the transmitter assembly (2) comprises: an electric motor (21), comprising an output shaft (211) extending along a first axis and rotated about the first axis, a transmission rod (221) extending along a second axis, rotating about the second axis and rotated by the output shaft (211), and a master cylinder (23), comprising a body (231) extending along the second axis and a piston (232) movable by sliding in the body (231), the piston (232) comprising a rod (233) and defining in the body (231) a rod-side chamber (234) and a bottom-side chamber (235), each configured to, in use, be filled with working fluid; And the transmitter assembly (2) is further configured such that: one of the transmission rod (221) and the rod (233) of the piston (232) of the master cylinder (23) has an external thread extending from a distal end, the other of the transmission rod (221) and the rod (233) of the piston (232) of the master cylinder (23) comprises a recess (24) extending along the second axis from a distal end and receiving an internal thread, a helical connection is formed between the external thread and the internal thread, such that rotation of the output shaft (211) in a first direction of rotation causes the piston (232) of the master cylinder (23) to slide in a first sliding direction, which reduces a volume of the rod-side chamber (234), expelling working fluid therefrom, and increases a volume of the bottom-side chamber (235), sucking working fluid therein, and that rotation of the output shaft (211) in a second direction of rotation, opposite to the first direction of rotation, causes the piston (232) of the master cylinder (23) to slide in a second sliding direction, opposite to the first sliding direction, which reduces the volume of the bottom-side chamber (235), expelling working fluid therefrom, and increases the volume of the rod-side chamber (234), sucking working fluid into it; and the master cylinder (23) thus creates the flow of working fluid, and the rod (221, 233), among the transmission rod (221) and the rod (233) of the piston (232) of the master cylinder (23), which carries the external thread penetrates at least partially into the recess (24) when the output shaft (211) is driven in the first direction of rotation and comes out at least partially from the recess (24) when the output shaft (211) is driven in the second direction of rotation.

2. Transmitter assembly (2) according to claim 1, characterized in that the transmission rod (221) carries the external thread and the transmitter assembly (2) further comprises a guide rail (28) and a guide part (29) cooperating to guide the sliding of the piston (232) of the master cylinder (23) and to block a rotation of the piston (232) of the master cylinder (23).

3. A transmitter assembly according to claim 1 or claim 2, characterized in that the transmitter assembly further comprises a threaded nut (25), a thread of the threaded nut (25) defining at least a portion of the internal thread.

4. Transmitter assembly (2) according to any one of claims 1 to 3, characterized in that the first axis coincides with the second axis, such that the output shaft (211), the transmission rod (221) and the rod (233) of the piston (232) of the master cylinder (23) are aligned, the transmission rod (221) being integral with the output shaft (211).

5. Transmitter assembly (2) according to any one of claims 1 to 3, characterized in that the transmitter assembly (2) further comprises a transmission mechanism (22), configured to transmit rotation between the output shaft (211) and the transmission rod (221), comprising: a flexible coupling (222) coupled to one end of the output shaft (211) and rotatable about the first axis, a first toothed wheel (223), coupled to the flexible coupling (222) and rotatably mounted about the first axis, a second toothed wheel (224), coupled to the transmission rod (221) and rotatably mounted about the second axis, and a toothed belt (225), engaged with the first and second toothed wheels (223, 224) and configured to transmit rotation between the first and second toothed wheels (223, 224).

6. Transmitter assembly (2) according to claim 5, characterized in that that the first axis and the second axis are distinct and parallel, and the motor (21) and the master cylinder (23) are arranged on the same side of a median plane of the first toothed wheel (223) perpendicular to the first and second axes.

7. Transmitter assembly (2) according to any one of claims 1 to 6, characterized in that the transmitter assembly (2) further comprises an elastic member (26) configured to urge the piston (232) of the master cylinder (23) in the second sliding direction, over at least a portion of a sliding range of the piston (232) of the master cylinder (23).

8. Motor system (1) for an active orthosis or an active prosthesis or an exoskeleton (4) characterized in that it comprises a transmitter assembly (2) according to any one of claims 1 to 7 and a receiver assembly (3) configured to receive the flow of driving fluid coming from the transmitter assembly (2) and convert it into a stress on the active orthosis or the active prosthesis or the exoskeleton (4), the receiver assembly (3) comprising: a first slave cylinder (31), comprising a body (311) and a piston (312) movable by sliding in the body (311), the piston (312) defining in the body (311) a rod-side chamber (314), configured to, in use, be filled with driving fluid and fluidly connected to the rod-side chamber (234) of the master cylinder (23), a second slave cylinder (32), comprising a body (321) and a piston (322) movable by sliding in the body (321),the piston (322) defining in the body (321) a rod-side chamber (324), configured to, in use, be filled with working fluid and fluidly connected to the bottom-side chamber (235) of the master cylinder (23), at least one transmission element (33), a first end of the at least one transmission element (33) being connected to a distal end of a rod (313) of the piston (312) of the first slave cylinder (31) and a second end of the at least one transmission element (33) being connected to a distal end of a rod (323) of the piston (322) of the second slave cylinder (32), and a rotation transmission member (34), engaged with the at least one transmission element (33) and configured to transform a stress of the at least one transmission element (33) into a relative rotation, around a third axis and in first and second directions of opposing stresses, of two fixing elements (41, 42) of, the active orthosis or active prosthesis or exoskeleton (4) intended to be respectively fixed to a user on either side of a joint to be stressed, a pivot axis of which coincides with the third axis, the bodies (311, 321) of the first and second slave cylinders (31, 32) being configured to be secured to the same fixing element (41) of the active orthosis or active prosthesis or exoskeleton (4);the motor system being further configured such that: rotation of the output shaft (211) in the first rotation direction causes the master cylinder (23) to introduce working fluid into the rod-side chamber (314) of the first slave cylinder (31) and to suck working fluid into the rod-side chamber (324) of the second slave cylinder (32), causing the rotation transmission member (34) to rotate in the first biasing direction, and rotation of the output shaft (211) in the second rotation direction causes the master cylinder (23) to introduce working fluid into the rod-side chamber (324) of the second slave cylinder (32) and to suck working fluid into the rod-side chamber (314) of the first slave cylinder (31), causing the rotation transmission member (34) to rotate in the second biasing direction.;

9. Engine system (1) according to claim 8, characterized in that the pistons (312, 322) of the first and second slave cylinders (31, 32) further define two respective bottom-side chambers (315, 325), both configured to, in use, be filled with fluid and fluidly connected to each other by an elastically deformable conduit (37).

10. Motor system (1) according to claim 8 or claim 9, characterized in that the receiving assembly further comprises an elastic member (38) connected to the rotation transmission member (34) and configured to bias the rotation transmission member (34) in the second direction of biasing, over at least a portion of a rotation range of the rotation transmission member (34).

11. Motor system (1) according to any one of claims 8 to 10, characterized in that the receiver assembly (3) comprises one of the following configurations: - a single flexible transmission element (33) having a first end connected to the distal end of the rod (313) of the piston (312) of the first slave cylinder (31) and a second end connected to the distal end of the rod (323) of the piston (322) of the second slave cylinder (32), and a rotation transmission member (34) comprising a cylinder-shaped portion in frictional engagement with the flexible transmission element (33); - two transmission elements (33) in the form of connecting rods, a first connecting rod having one end articulated to the distal end of the rod (313) of the piston (312) of the first slave cylinder (31) and another opposite end articulated to the rotation transmission member (34), and a second connecting rod having one end articulated to the distal end of the rod (323) of the piston (322) of the second slave cylinder (32) and another opposite end articulated to the rotation transmission member (34); - two transmission elements (33) in the form of toothed bars and a rotation transmission member (34) comprising at least one toothed wheel, a first toothed bar having one end connected to the distal end of the rod (313) of the piston (312) of the first slave cylinder (31) and another opposite end meshed with the rotation transmission member (34), and a second toothed bar having one end connected to the distal end of the rod (323) of the piston (322) of the second slave cylinder (32) and another opposite end meshed with the rotation transmission member (34); and - two flexible transmission elements (33), a first flexible transmission element (33) having one end connected to the distal end of the rod (313) of the piston (312) of the first slave cylinder (31) and another opposite end connected to the rotation transmission member (34), and a second flexible transmission element (33) having one end connected to the distal end of the rod (323) of the piston (322) of the second slave cylinder (32) and another opposite end connected to the rotation transmission member (34).

12. Engine system (1) according to any one of claims 8 to 10, characterized in that the receiver assembly (3) comprises one of the following configurations: - a single flexible transmission element (33) and a rotation transmission member (34) comprising a cam-shaped portion (341), the flexible transmission element (33) engaging by friction with the cam-shaped portion (341); and - two flexible transmission elements (33) and a rotation transmission member (34) comprising two cylindrical elements (342), concentric and of different diameters, a first flexible transmission element (33) having one end connected to the distal end of the rod (313) of the piston (312) of the first slave cylinder (31) and having another opposite end connected to a cylindrical element (342) and partially wound thereon over at least a portion of a rotation range of the rotation transmission member (34), and a second flexible transmission element (33) having one end connected to the distal end of the rod (323) of the piston (322) of the second slave cylinder (32) and having another opposite end connected to the other cylindrical element (342) and partially wound thereon over at least a portion of the rotation range of the rotation transmission member (34).

13. Engine system (1) according to claim 12, characterized in that the engine system (1) is configured to maintain the same hydraulic reduction factor and is sized to comply with the equation below: [Math.3] _ Stm St2xR2 SiURl with: Stm the annular cross-section of the rod-side chamber (234) of the master cylinder (23), Sfm the circular cross-section of the bottom-side chamber (235) of the master cylinder (23), Stl the annular cross-section of the rod-side chamber (314) of the first slave cylinder (31), St2 the annular cross-section of the rod-side chamber (324) of the second slave cylinder (32), RI the radius of the cylindrical element (342) on which the flexible transmission element (33) connected to the rod (313) of the piston (312) of the first slave cylinder (31) is partially wound, respectively the radius of the portion of the cam-shaped part (341) engaged with the flexible transmission element (33) when the rod (313) of the piston (312) of the first slave cylinder (31) applies traction on the cam-shaped part (341), and R2 the radius of the cylindrical element (342) on which the flexible transmission element (33) connected to the rod (323) of the piston (322) of the second slave cylinder (32) is partially wound, respectively the radius of the portion of the cam-shaped part (341) engaged with the transmission element (33) flexible transmission (33) when the rod (323) of the piston (322) of the second slave cylinder (32) applies traction to the cam-shaped part (341).

14. Active orthosis or active prosthesis or exoskeleton (4) comprising two fixing elements (41, 42) intended to be respectively fixed to a user on either side of a joint to be stressed, characterized in that the active orthosis or the active prosthesis or the exoskeleton (4) further comprises a motor system (1) according to any one of claims 8 to 13, the third pivot axis of which coincides with the pivot axis of said joint to be stressed and a control system (C) of the motor system (1).

Images