Artificial muscle, exoskeleton, related method and system
Described herein are artificial muscles for soft exoskeletons. Each muscle comprises first and second tendons with attachment means for connecting to the exoskeleton's muscle connectors. A deformable muscle core, preferably enclosed in an outer sleeve, extends between the tendons. Each tendon receives a respective end of the muscle core, with the first tendon featuring an actuation interface for connecting to an actuator. When actuated, the muscle core changes length, causing the tendons to move toward each other as actuation increases and away from each other as actuation decreases. This mechanism enables the artificial muscle to replicate natural muscle contraction and extension, providing force and movement assistance to soft exoskeleton wearers through a flexible, adaptable design.
1 . An artificial muscle for a soft exoskeleton, the artificial muscle comprising:
a first tendon and a second tendon, each of the first tendon and the second tendon comprising an attachment means for attachment of said artificial muscle to a muscle connector of the exoskeleton;
a muscle core made of a deformable material extending between said first tendon and said second tendon, the muscle core comprising an outer sleeve;
wherein each of said first and said second tendon is adapted for receiving a respective end of said muscle core; wherein said artificial muscle comprises means for connection of said muscle core to an actuator for generating an actuation; wherein said muscle core is adapted to undergo a change in length when being actuated, thereby causing said first and said second tendon to move towards each other when said actuation is on or increased, and to move away from each other when said actuation is off or reduced;
wherein said muscle core further comprises one or more inner sleeves extending between said first and second tendons; and wherein said outer sleeve extending between said first and second tendons circumferentially surrounds the one or more inner sleeves, and
wherein said one or more inner sleeves is at least two inner sleeves.
2 . The artificial muscle according to claim 1 , wherein each of said first tendon and said second tendon comprises attachment means for connection to respective portions of an exoskeleton, wherein said attachment means of at least one of said first and said second tendon are releasable attachment means for allowing the respective one of said first and said second tendon to be inserted and/or removed individually from said exoskeleton and/or are adjustable attachment means for allowing the muscle to be tightened with respect to the exoskeleton.
3 . The artificial muscle according to claim 2 , wherein
the attachment means of each of said first and said second tendon are releasable attachment means for allowing said artificial muscle to be inserted and/or removed from said exoskeleton, and/or
said means for connection to said actuator is an actuation interface comprised in said first tendon being a releasable actuation interface for allowing at least said first tendon to be inserted and/or removed from the soft exoskeleton.
4 . The artificial muscle according to claim 3 , wherein said means for connection to said actuator is an actuation interface comprised in said first tendon being a releasable actuation interface for allowing at least the artificial muscle to be inserted and/or removed from the soft exoskeleton.
5 . The artificial muscle according to claim 1 , wherein the outer sleeve comprising
an outer layer comprising a plurality of perforations provided over its surface, and
a flexible inner layer;
wherein a diameter of said perforations is adapted for receiving expanded portions of said inner layer within said perforations during expansion of said muscle due to said actuation.
6 . The artificial muscle according to claim 5 , wherein said outer layer is a braided outer layer.
7 . The artificial muscle according to claim 5 , wherein said flexible inner layer is a silicone inner layer.
8 . The artificial muscle according to claim 5 , wherein the diameter of said perforations is adapted for receiving expanded portions of said inner layer within said perforations during expansion of said muscle upon insertion of a fluid on which actuation is based.
9 . The artificial muscle according to claim 1 , wherein at least one of said at least two inner sleeves comprises:
an outer layer comprising a plurality of perforations provided over its surface, and
a flexible inner layer;
wherein a diameter of said perforations is adapted for receiving expanded portions of said inner layer within said perforations during expansion.
10 . The artificial muscle according to claim 9 , wherein said outer layer is a braided outer layer.
11 . The artificial muscle according to claim 9 , wherein said flexible inner layer is a silicone inner layer.
12 . The artificial muscle according to claim 9 , wherein said flexible inner layer is impermeable with respect to a fluid.
13 . The artificial muscle according to claim 9 , wherein the diameter of said perforations is adapted for receiving expanded portions of said inner layer within said perforations during expansion of said muscle upon insertion of a fluid on which actuation is based.
14 . A soft exoskeleton comprising
at least one artificial muscle according to claim 1 ; and
a control unit comprising an actuator for generating an actuation for said at least one artificial muscle.
15 . The soft exoskeleton according to claim 14 , wherein each of said first and said second tendon is adapted for receiving a respective end of a muscle core; and wherein, of said first tendon and said second tendon, it is said first tendon that is located closest to said control unit, said first tendon comprising an actuation interface for connection of said muscle core to said control unit.
16 . The soft exoskeleton of claim 14 , further comprising a fascial network comprising a plurality of fascial connections for supporting the at least one muscle, the plurality of fascial connections comprising:
a plurality of muscle connectors connecting the at least one muscle via the first and second tendons to further portions of the fascial network, and
a plurality of complementary fascial connections, of which at least one is adapted for providing tightening with respect to a user when using the exoskeleton and for supporting the plurality of muscle connectors.
17 . The soft exoskeleton of claim 16 , wherein said first tendon comprises an actuation interface for connection of the first tendon to said control unit, wherein the exoskeleton comprises an actuation connection for connecting said actuation interface of said muscle core to said control unit supported by at least one of said plurality of complementary fascial connections.
18 . The soft exoskeleton according to claim 16 , wherein which at least one of the plurality of complementary fascial connections is adapted for providing releasable tightening with respect to the user when using the exoskeleton and for supporting the plurality of muscle connectors.
19 . The soft exoskeleton of claim 14 , wherein
said exoskeleton comprises an anchor element, said anchor element being any of a waist band, an artificial patella or a shoe and/or wherein said one or more muscles comprise at least two muscles forming an agonist-antagonist pair, wherein said control unit is configured to reduce and/or stop the actuation of one of said agonist-antagonist pair when the actuation of the other one of said agonist-antagonist pair is started and/or increased.
20 . The soft exoskeleton of claim 16 , wherein said exoskeleton relates to lower limbs, wherein said plurality of complementary fascial connections comprises a hip belt adapted for providing releasable tightening with respect to the user when using the exoskeleton and for supporting the plurality of muscle connectors, wherein said exoskeleton further comprises an anchor element being a waist band tightened to the user by said hip belt, and wherein said control unit is supported by said waist band.
21 . The soft exoskeleton of claim 14 , wherein said exoskeleton operates according to a passive or an active mode, wherein said active mode relates to at least one of said at least one artificial muscle being actuated to an active level of actuation and wherein said passive mode relates to said at least one artificial muscle being actuated to a passive level of actuation, wherein said active level of actuation is higher than said passive level of actuation, and wherein the control unit is configured to detect at least one of
a user-movement-based activation trigger for switching from the passive mode to the active mode, and
a user-movement-based deactivation trigger for switching from the active mode to the passive mode.
22 . The soft exoskeleton according to claim 21 , wherein said active level of actuation corresponds to full actuation and/or wherein said passive level of actuation corresponds to no actuation.
23 . The soft exoskeleton of claim 14 comprising at least one signal module connected to said control unit; wherein the signal module comprises at least one of: a stimuli generator configured for generating stimuli for transfer to a user and/or an environment of the user; and a sensor located in the vicinity of the user and configured for measuring measurement data relating to the user and/or the environment of the user.
24 . The soft exoskeleton of claim 23 , wherein at least part of signal module is comprised in at least one of: a fascial network, at least one tendon or the muscle core of at least one artificial muscle, and/or the control unit.
25 . The soft exoskeleton of claim 24 , wherein said control unit is configured for generating, based on stimuli-related data, an instruction for stimuli; and transmitting, to said signal module, said instruction for stimuli; and wherein said stimuli generator is configured for generating said stimuli based on said instruction for stimuli.
26 . The soft exoskeleton of claim 23 , wherein the signal module comprises a sensor located in the vicinity of the user; wherein said at least one signal module is configured for:
measuring, via said sensor, measurement data;
transmitting said measurement data to the control unit;
preferably, receiving an instruction for stimuli from the control unit;
preferably, generating, via said stimuli generator and based on said instruction for stimuli, stimuli, for transfer to the user for providing biofeedback;
and wherein said control unit is configured for:
receiving, from said at least one signal module, said measurement data;
generating, based on a level of said actuation and based on said measurement data, at least one of
an instruction for stimuli for providing biofeedback, or
a new value for said level of said actuation, respectively;
transmitting, to said signal module, said instruction for stimuli and/or controlling said actuator for generating said actuator for generating said actuation based on said new value, respectively.
27 . The soft exoskeleton of claim 26 , wherein said generating comprises generating each of said instruction for stimuli for providing biofeedback for said stimuli generator comprised in said signal module and said new value for said level of said actuation; and wherein said control unit is configured for performing each of transmitting, by said control unit and to said signal module, said instruction for stimuli; and generating, by said stimuli generator and based on said instruction for stimuli, said stimuli, for transfer to the user for providing biofeedback; and controlling said actuator for generating said actuation based on said new value for providing biofeedback.
28 . The soft exoskeleton according to claim 27 , wherein said stimuli are vibrations.
29 . The soft exoskeleton according to claim 26 , wherein said measurement data is a pressure measurement originating from the user wearing said exoskeleton.
30 . The soft exoskeleton according to claim 26 , wherein said at least one signal module is additionally configured for:
receiving an instruction for stimuli from said control unit; and/or
generating, via said stimuli generator and based on said instruction for stimuli, wherein said stimuli are vibrations for transfer to the user for providing biofeedback.
31 . The soft exoskeleton according to claim 23 , wherein said stimuli are vibrations and/or light radiation.
32 . The exoskeleton according to claim 14 , comprising a fascial network, the fascial network comprising a plurality connection for supporting at least one of artificial muscles.
33 . The artificial muscle according to claim 1 , wherein said means for connection to said actuator is an actuation interface comprised in the first tendon.