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The present invention relates to the field of wearable robotics, specifically exoskeleton systems designed to assist individuals with mobility impairments in performing daily activities. According to an aspect, the present invention focuses on transitioning from the clinical setting to home and community use.
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Individuals with motor neurological impairments (such as spinal cord injuries, strokes, multiple sclerosis, or traumatic brain injuries, etc.) often experience significant limitations in their ability to control movement in their lower limbs and trunk. These conditions lead to mobility and walking challenges that can greatly impact their quality of life. Robotic exoskeletons are commonly used in physical therapy or rehabilitation programs to support gait training, enabling users to regain mobility in clinical environments. Such devices not only facilitate improved rehabilitation outcomes due to neuroplasticity but also contribute to overall health improvements, enhancing the independence and well-being of patients.
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Currently, some commercially available robotic exoskeletons, such as ReWalk (
US2019282428 ) and Indego (
US2023075154 ), are being marketed for home and community use. However, due to the fact that there is no variation between the clinical and home versions, certain limitations persist. For example, these exoskeletons have limited functionalities, and are too bulky and heavy for easy use in domestic environments, making them difficult to maneuver and transport. Additionally, they require significant time for donning/doffing, and their cost is high, restricting their generalized adoption.
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With personal use exoskeletons, it is common for users to face challenges related to their portability, maintenance, or adaptability to their specific needs. For example, transporting or storing a device of this nature can be inconvenient due to its size. Moreover making adjustments for a specific user often requires significant time and resources. Additionally, performing repairs or maintenance can be complex and/or costly. These difficulties can create frustration and limit the practicality of the exoskeleton in real-world settings. Therefore, an exoskeleton should incorporate design features that simplify transportation, enable straightforward manufacturer personalization for a specific user, and allow for localized maintenance to enhance both usability and overall patient satisfaction.
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Current exoskeletons address mobility and rehabilitation needs using a variety of structural and functional designs, each with specific features that cater to different use cases.
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Devices like "Indego" (
US2023075154 by Parker Hannifin GmbH ) consist of five snap-together components corresponding to each entire section (the segment plus the joint are the same piece):
- Lumbar section
- Upper leg section: includes the thigh segment and the joints of the hip and knee
- Lower leg section: includes the shank segment, the foot segment and the ankle joint
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They offer 3 different sizes (Small, Medium and Large) for the upper leg, lower leg, and lumbar sections. The modularity allows improving the transportation and provides a set of interchangeable components, yet it does not allow to fully configuring the exoskeleton to the anatomic shape of the body and if reparations were needed large parts must be sent for them to be performed.
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Devices like the EksoNR by Ekso Bionics, ReWalk by Lifeward and the HAL (Hybrid Assistive Limb) by Cyberdyne incorporate adjustable elements, such as telescoping parts to fit users of varying sizes. These designs provide greater flexibility compared to rigid systems. However, the adjustment process often requires tools, which can make reconfiguration time-consuming and less practical in settings with multiple users. All these moving telescopic parts increase the complexity and cost of manufacturing these devices. Moreover, for home use, these costly features are worthless, since the exoskeleton is not to be worn by several users.
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The MYO Suit by MyoSwiss exemplifies a lightweight and portable approach, focusing on minimizing bulk and weight for ease of use and transport. While this improves accessibility for patients using the device in daily life, such designs typically sacrifice the robustness and structural flexibility needed for broader applications, such as heavy-duty rehabilitation or diverse user adaptation. This device is only suitable for conditions where users can support their own weight without external assistance.
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In short, there is a need in the market for exoskeletons for domestic use.
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According to an aspect, the present invention intends to offer solutions to the before mentioned problems and needs. It is an object of the present invention to disclose an exoskeleton which would allow at least one of the following:
- Reducing manufacturing costs;
- Easier adaptation of the skeleton to better follow the anatomical shape of the body of each user;
- Facilitating transportation and shipping;
- Reducing repair costs;
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More in particular, the present invention discloses an exoskeleton comprising a modular system having detachable elements which are connected via electrical and/or mechanical means characterized in that said modular system comprises:
- a back module,
- a hip link,
- a preferably motorized hip module,
- a thigh link,
- a preferably motorized knee module,
- a shank link, and
- a foot module.
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The back module is connected to the hip module via the hip link. Likewise, the hip module is connected to the knee module via the thigh link. The knee module is connected to the foot module via the shank link. Preferably, at least the hip link and the thigh link, and more preferably all link elements (hip link, thigh link and shank link), have tubular shape.
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Preferably, the exoskeleton has a bilateral structure with a hip link, a preferably motorized hip module, a thigh link, a preferably motorized knee module, a shank link and a foot module per side.
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Thus, the proposed exoskeleton according to the present invention can comprise standardized modules for the foot, knee, hip and back that are connected through customizable link elements. In a preferred embodiment, said customizable link elements are made of aluminium.
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The link elements according to the present invention, preferably being tubular, are affordable and easy to produce, being able to offer a tailor-made exoskeleton at a lower cost.
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The foot, knee, hip and back modules can be standardized, pre-manufactured and stocked before an order is placed, which consequently reduces production lead times.
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The modularity of the present invention allows for maintenance and/or repairing processes to be performed on individual modules, avoiding the need to send the entire exoskeleton for servicing, reducing downtime and repair costs significantly. In some embodiments, size adjustments to the exoskeleton can be made through telescopic parts and pin locking mechanisms.
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Preferably, the exoskeleton is made of modules and links which snap together. More preferably, the modules and links have respective quick connection terminals for connecting to a corresponding link or module.
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Preferably, the hip link is releasably connected to the back module. More preferably, the hip link is releasably connected to the hip module. Even more preferably, all the connections between modules and links are releasable. In a preferred embodiment, each module and/or link has at least an external interface for connecting to a respective link and/or module. Preferably, at least one of the interfaces allows for a common mechanical and electrical connection. More preferably the connection between the back module and each hip link, between each hip link and the respective hip module, between each hip module and the respective thigh link and between each thigh link and the respective knee module is a common mechanical and electrical connection. Preferably any one of the cited connections is a quick connection. Also preferably, any of the cited connections is a self-latching connection. More preferably, all the cited connections are quick connections. Even more preferably, all the above cited connections are self-latching connections.
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Preferably, each module and/or link has at least an external interface for connecting to a respective link and/or module. More preferably, at least one of the interfaces allows for a common mechanical and electrical connection. Even more preferably, the interfaces corresponding to the connection between the back module and the hip link, the hip link and the hip module, the hip module and the thigh link, and the thigh link and the knee module are common mechanical and electrical connections.
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More preferably, each of said common mechanical and electrical connection(s) comprise(s) a seamless electrical connection for power and signal transmission via connectors.
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Preferably, at least one of the connections is a snap-on connection or a self-latching connection. More preferably, all the connections between modules and links are snap-on connections or self-latching connections.
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Preferably, at least one of the connections comprises mechanical fixing means. Said fixing means can comprise, for example, bolts which should be screwed, or retractable pins for fixing the connections. In particularly preferred embodiments, all the connections between link and module (or viceversa) comprise fixing means with retractable pins for latching the connections. This makes assembly easier for home environments and domestic use applications of the present invention.
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In some embodiments, the connections between the thigh link and the hip module, the thigh link and the knee module, the hip link and the hip module and the shank link and the foot module comprise fixing means, said fixing means preferably comprising bolts.
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Also preferably, at least one of the connections is fixed by means of a retractable pin, more preferably the connection being a single action connection. Also preferably, at said at least one connection a link is inserted into a module housing, where a retractable pin automatically withdraws to allow insertion, the pin locking into a recess when the link element reaches its final position, thus self-latching the connection and securing the connection mechanically. More preferably, all connections between said links and said module are single-action connections with a retractable pin. Even more preferably, at said all single-action connections a link is inserted into a module housing, where a retractable pin automatically withdraws to allow insertion, the pin locking into a recess when the link element reaches its final position, thus securing the connection mechanically.
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Preferably, each module comprises a plastic sliding sheet integrated to facilitate the assembly of a corresponding link. More preferably, said sheet is located at an external housing of the module.
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Preferably, each hip module and each knee module comprise a respective actuator.
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Preferably, each knee module comprises an electromagnetic safety brake.
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The exoskeleton according to the present invention can comprise a remote controller to operate the exoskeleton.
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Preferably, the exoskeleton is a snap-together assembly system, more preferably tool-free, thus allowing the users to set up the device easily.
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Preferably, the foot module is passively articulated with a resilient means.
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Preferably, the external housing of the links is a tube, more preferably a single tube. Also preferably, the external housing of the links is made of aluminium.
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For a better understanding, there are attached, by way of explanation and not limitation, some figures related to a possible realization of the present invention.
- Fig. 1 shows an example of the exoskeleton according to the present invention.
- Fig. 2 shows an example of a leg module comprising a hip link, a motorized hip module, a thigh link, a motorized knee module, a shank link and a foot module.
- Fig. 3 shows an example of a back module.
- Fig. 4 shows a sectioned view of a foot module.
- Fig. 5 shows a sectioned view of a motorized knee module.
- Fig. 6 shows a sectioned view of a pin assembly system.
- Fig. 7 shows a sectioned view of fixed links between the thigh link and the motorized knee module.
- Fig. 8 shows a sectioned view of a connection part of a motorized hip module.
- Fig. 9 shows an example of a link element.
- Fig. 10 shows a section cut of a link element.
- Fig. 11 shows the various mechanical links, supports and standardized modules.
- Fig. 12 shows a male connector.
- Fig. 13 shows a female connector.
- Fig. 14 shows a perspective view of the remote controller.
- Fig. 15 shows a different perspective view of the remote controller.
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From Fig. 1 to Fig. 5, generic and more specific views are provided to show an embodiment of a bilateral exoskeleton 1.
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Fig. 1 shows an embodiment of the exoskeleton 1 which presents a bilateral distribution. The exoskeleton 1 is composed of a back module 10 and two leg segments 20. The exoskeleton 1 can be attached to the user's torso, legs and feet via straps and supports (straps not shown in the pictures).
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Each leg segments 20 comprises a motorized hip module 21, a motorized knee module 22, a foot module 23, a hip link 31, a thigh link 32 and a shank link 33. Each leg segment is connected to the back module 10. The back module 10 is configured to sit against the user's back and houses two rechargeable and swappable battery packs, an Electronic Central Unit (ECU), an inertial measurement unit (IMU) as well as communication modules, like, for example, Wi-Fi and Bluetooth modules. The exoskeleton 1 is provided with four battery-powered motors that drive the knee 22 and hip 21 modules assisting in flexion-extension movements. Each leg segment 20 houses electrical actuators 221, 211 located in respective knee modules 22 and hip modules 21, each module corresponding to a respective knee joint or hip joint. The exoskeleton 1 also comprises servo drivers to control the actuators, an electromagnetic safety brake at the knee module, and at least an IMU sensor for motion tracking.
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Degrees of freedom of the hip 21 and knee modules 22 other than those provided by the actuators and shown in the figures are restricted. The foot module 23 of the exoskeleton is passively articulated with elastic means (shown in Fig. 4) within a limited range of motion.
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The back module 10 is releasably connected to both hip links 31. Each hip link 31 is releasably connected to a respective hip module 21. Each hip module 21 is releasably connected to a respective thigh link 32. Each thigh link 32 is releasably connected to a respective knee module 22. Each knee module 22 is releasably connected to a respective shank link 33. Each shank link 33 is releasably connected to a respective foot module 23.
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The back module 10 is located at a position covering a user lower back. Each hip module 21 covers a respective user's hip joint. Each knee module 22 covers a respective user's knee joint. Each foot module 23 covers a respective user's ankle joint. Each thigh link 32 runs along a respective user's thigh. Each shank link 33 runs along a respective user's shank. Each hip link 31 runs between a respective hip module 21 and the back module 10. Connections between modules 10, 21, 22, 23 and links 31, 32, 33 are made through interfaces on external surfaces of each respective module 10, 21, 22, 23. In the embodiment shown, no link 31, 32, 33 is directly connected to another link 31, 32, 33. The links are connected to each other via a respective module 10, 21, 22, 23. No module 10, 21, 22, 23 is directly connected to another module 10, 21, 22, 23. They are connected via respective(s) link 31, 32, 33.
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The hip links 31 and the thigh links 32 have tubular shape, with connectors/interfaces for connecting to respective modules at its respective free ends. Power and/or signal cables run inside the tube of said links 31, 32. The housing of the hip and thigh links 31, 32 is a single tube made of aluminium. The shank link 33 can also have tubular shape.
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The exoskeleton can be easily adapted to a body of a user by bending the tubular links and or altering the length of the tubular links, the modules being unaltered. Moreover, repairing the exoskeleton is easier, since any module can be easily detached from the rest of the exoskeleton and remain small in size, which allows for easy shipping for repairing or substituting a module. Links can also be individually detached for repairing or being substituted.
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Fig. 2 allows seeing in more detail a leg segment 20. The thigh link 32 extends from the hip module 21 to the knee module 22. Each hip module 21 has a hip actuator 211, and each knee module 22 has a knee actuator 221. The actuators apply force to move the legs of the exoskeleton 1 to assist the patient in the motion of walking. The actuators 211, 221 are also used to facilitate the transfer of the patient to the exoskeleton 1 by positioning the exoskeleton 1 in a certain position and locking the hip and knee modules 21, 22.
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The shank link 33 of the embodiment shown has no actuators. The foot modules 23 also lack actuators. They comprise respective footplates which are rotatably connected to respective ankle joint parts 231 having an interface for receiving the shank link 33.
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Each hip module 21 also has a rigid support 321 attached to it and each knee module 22 has a respective attached rigid support 331, which helps to transfer the load and movement from the user to the exoskeleton 1 frame, and vice-versa. Straps for connection to the patient as well as padding parts are not shown in the pictures.
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In embodiments alternative to the one shown in the pictures, size adjustments to the exoskeleton 1 can be made through telescopic parts and pin locking mechanisms.
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Fig. 3 shows a frontal view of the back module 10 from its backside. The back module 10 accommodates two rechargeable and swappable battery packs, an Electronic Central Unit (ECU), an inertial measurement unit (IMU) as well as communication modules, like, for example, Wi-Fi and Bluetooth modules. The back module 10 can be fixed to the patient via lumbar belt straps (not shown in the pictures). An upper trunk support 11 is attached to the back module 10. The upper trunk support 11 has handles for use by a companion if necessary. The upper trunk support 11 can be used for fixing shoulder straps for those users with higher injuries or limited trunk control. The back module 10 connects, via respective interfaces located on the external surfaces of the module, to the hip link 31.
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The exoskeleton's ECU can allow the user to transfer between the different states of the exoskeleton 1, like, for example: (1) from sitting to the Transfer state, which prepares the user to don the device; (2) to the sit-to-stand transition, where the exoskeleton 1 actively assists the knee and hip joints; (3) to the standing state, where actuators 221, 211 provide the necessary torque to stabilize the user's legs and trunk; (4) to walking mode, where the exoskeleton 1 drives the knee and hip modules 22, 21 in a natural gait pattern; and (5) to the stand-to-sit transition, where the device helps the user return to a seated position on a chair or medical bed. Beyond these primary states, the exoskeleton 1 can also include a range of more specific states, such as turning or ascending/descending stairs and ramps.
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The ankle joint part 231 can house at least one spring (not shown in Fig 4), allowing the foot module 23 to move in plantarflexion and dorsiflexion. This rotation is loaded with the at least one spring, returning the user to a "neutral" position.
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Fig. 5 shows a sectioned view of a motorized knee module 22 in which the actuator 221 and the electromagnetic safety brake 222 are located.
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Fig. 6 illustrates a connection between the back module 10 and the hip link 31 and its use. The connection comprises a single-action mechanism for quick assembly and a double-action mechanism for safe disassembly. The connection connects the back module 10 and the hip link 31 both mechanically and electrically. The connection between the hip link 31 and the hip module 21, the hip module 21 and the thigh link 32, the thigh link and the knee module 22 can be made in the same way. The connection between the knee module 22 and the shank link 33, and the connection between the shank link 33 and the foot module 23 can be made in the same or a similar way, not being necessary to establish any electrical connection wherein the foot module 23 has no motor or any other active actuator that requires power, or any sensor. In general, any mechanical connection can also have an electrical connection, depending, for example, on which modules are motorized.
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The connection comprises an entry on the external housing of the back module 10 which allows access to a space having a retractable pin 41 disposed at 90° respective to the entry and an electrical connector (in this case, an electrical male connector 51) located in front of the entry, and an interface of the link located at a corresponding end of the link which comprises a conjugated electrical connector (in this case an electrical female connector 52) and a recess 42 conjugated with the retractable pin 41. The recess 42 can be, for example, a pre-drilled hole located on a corresponding face of the female connector 52. The retractable pin 11 can comprise a recovery spring or element (not shown in the figures).
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During the assembly, as shown in Fig. 6, the link element (the hip link 31 in the picture's case) is inserted into the module housing, where the retractable pin 41 automatically withdraws to allow a smooth insertion. When the link element reaches its final position, the retractable pin 41 locks into the recess 42, securing the connection mechanically. Simultaneously, the male and female connectors 51, 52 inside, respectively, the housing and the link element engage, creating a seamless electrical connection for power and signal transmission.
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To facilitate smooth assembly, a technical plastic sliding sheet 53 is integrated into the housing, reducing friction and ensuring that link elements can be inserted and removed effortlessly.
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Meanwhile, to detach the link, the pin 41 must be manually retracted before the link is removed from the housing. This design can allow easy assembly and prevent accidental disconnections during use.
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The assembly system of Fig. 6 is used at the connection between the back module 10 and hip link 31 and between the shank link 33 and the foot module 23.
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Referring to the connection system, the preferred embodiment shown in the figures has connections which are both mechanical and electrical from the back module 10 to the knee module 22, and mechanical connections only between the knee module 22 and the foot module 23. More In particular, Fig. 7 show an embodiment of the connection between the thigh link 32 and the knee module 22 and Fig. 8 show an embodiment of the connection between the thigh link 32 and the hip module 21. Said connections display a set of fixed joints designed to enhance reliability and improve overall performance. The fixed joints can minimize potential play between the components which can provide a more stable and precise behaviour during operation. Eliminating unnecessary movement at key junctions, the fixed joints can improve the alignment and efficiency, particularly during dynamic activities such as walking, standing or transitioning between states.
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Preferably, each fixed joint uses a robust screw-fastened connection, which can provide a secure and durable bond that can maintain structural integrity. This design can prioritize reliability while reducing wear over time, further contributing to the exoskeleton's 1 longevity and consistent functionality. In the embodiment, the fixed joints comprise bolts 60 which can be screwed into the link trough the module housing. After connecting the link and the module, the bolts 60 must be screwed.
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Fig. 9 and Fig. 10 show an example of a thigh link 32 presenting a series of holes 3211 for bolts 60. Fig. 10 is a cross sectional view of the thigh link 32, wherein it can be seen that the link is hollow, cables (not show in the picture) are able to run along the link.
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Fig. 11 shows the different components that comprise the exoskeleton 1 separately, those being the link elements, the supports and the modules. Each one can be easily detached from the others.
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Fig. 12 and Fig. 13 show a male connector 51 and a female connector 52 respectively, in particular a power/signal header for the male one and a power/signal socket for the female one. Said male connector 51 comprises a Hot-Swap and In-Rush Current Controller circuits which can protect the system from overcurrents that can cause damage to circuits, components, or batteries and can prevent issues like system resets or sparks, which could degrade the connector over time.
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The electrical connection is performed by the joint of the two connectors 51 and 52, which, in a preferred embodiment are mounted on a custom PCB. Said connectors are mechanically isolated from the structural elements of the exoskeleton, so that it can be prevented that mechanical loads, such as forces generated during movement, vibration or impacts, damage the connectors.
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Fig. 14 and Fig. 15 show views of an embodiment of the remote controller 80 by which the user can operate the exoskeleton 1. The remote controller 80 can be a wireless device controlled by a mobile device, for example a smartphone. Said smartphone can be located in a specific area 81 of the remote controller 80. Optionally, the controller 80 can feature two buttons 82 for switching between states and an additional action button 83 for specific commands. Optionally, below the remote there can be a touch sensor (not shown in the pictures) that can allow the user to navigate through menus displayed on the mobile device.
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Although the invention has been presented and described with reference to embodiments thereof, it will be appreciated that these are non-limiting embodiments of the invention, and therefore several different structural or other details could become obvious to a person skilled in the art after interpreting the subject matter disclosed in the present description, claims and drawings. Consequently, the present invention encompasses all variants and equivalents if they can be considered to fall within the broadest scope of the claims which follow.