Patent Publication Number: US-2022218551-A1

Title: Ankle-Assisted Exoskeleton Device

Description:
TECHNICAL FIELD 
     The present invention relates to the technical field of wearable devices, and in particular, to an ankle assisting exoskeleton device that provides auxiliary force for user&#39;s ankle and can be used daily. 
     BACKGROUND 
     At present, wearable devices for lower limbs are designed for different purposes, including wearable devices that enhance human strength, wearable devices that provide rehabilitation training, and wearable devices that improve movement efficiency and reduce human energy consumption. For the purpose of enhancing human strength and rehabilitation, wearable lower limb devices or exoskeletons usually rely on a full-leg rigid metal structure to provide external body support. These lower limb exoskeleton systems can enable healthy people or physically disabled people to perform tasks that cannot be accomplished with their own strength. However, the existing rigid wearable devices have the following disadvantages in coordinating human actions and improving movement efficiency: (1) The interference between the device and the biological joints can introduce the misalignment of the device joints and the biological joints during movements; (2) The natural motion of the biological joints are restricted because the degrees of freedom (DOF) of the device are less than the DOF of the lower limb joints of the human body; (3) The user consumes extra energy when using the device due to the large weight and inertia of the device structure are not fully compensated by the device itself. Slow actuation response and lack of accurate human intension detection also make it difficult to use such full-leg rigid exoskeleton devices freely in daily life. 
     At present, some soft exosuit devices are made of lightweight and flexible materials to reduce constraints on biological joints and provide joint assistance. Such devices provide a lighter solution for assisting joints. However, these soft exosuit devices rely on the user&#39;s skin surface to provide tangential force as a reaction force for assisting joints. In other words, these devices provide auxiliary forces to the user&#39;s limb joints on one side, and apply tangential forces tangential to the skin surface to the user&#39;s skin surface on the other side. These tangential forces rub and squeeze user&#39;s skin, and make the device discomfortable to use. Moreover, when the user&#39;s muscle stiffness is insufficient or the shape of limb is not cone like, which can make it difficult to provide a large enough tangential force as a reaction force of the auxiliary force. Then, these devices cannot be properly used. 
     Therefore, there is a rising need for a wearable robotic device that can be easily worn without restricting user&#39;s joints, and does not rely on user&#39;s skin surface to provide tangential force while providing lower limb assistance, so as to improve user&#39;s daily mobility and action efficiency. 
     SUMMARY OF THE INVENTION 
     In order to solve at least one of the above-mentioned defects in the prior art, the present invention proposes an ankle assisting exoskeleton device, which includes: an actuator configured to be worn on a part near center of gravity of a user (for example, behind a waist); 
     a lower limb support; and 
     a cable configured to controllably apply a pulling force to the lower limb support when driven by the actuator, wherein, 
     the lower limb support includes: 
     a calf ring configured to encircle the user&#39;s calf; 
     a link assembly attached to the calf ring and extending downwards; and 
     a foot support hinged to a lower end of the link assembly and connected to the cable, and the foot support is configured to drive the user&#39;s foot to rotate around ankle joint through an upward pulling force exerted on the user&#39;s sole. 
     According to an embodiment of the present invention, a front end of the foot support is configured to clamp the user&#39;s foot in a vertical direction, and a rear end of the foot support is configured to be located behind the user&#39;s heel, and the rear end is connected with the cable; the lower limb support further includes: a torsion spring provided between the lower end of the link assembly and the foot support, which is configured to apply a torque to the foot support causing the front end thereof to be lifted upwards; and a sole pulling ring hinged to the foot support between the front end and the rear end of the foot support, which is configured to pull the user&#39;s sole. 
     According to a possible embodiment of the present invention, the foot support includes a pair of support arms connecting the rear end with the front end on left and right sides, and the front end consists of support arm front ends of the pair of support arms and an instep strap attached thereto, the instep strap is configured to partially cover the user&#39;s instep. 
     According to a possible embodiment of the present invention, the link assembly includes a pair of connecting rods arranged on left and right sides of the foot support, and an upper end of each of the pair of connecting rods is respectively attached to left and right sides of the calf ring, an lower end of each of the pair of connecting rods is respectively hinged to the foot support. 
     According to a possible embodiment of the present invention, the link assembly includes a support block that connects the pair of connecting rods with each other at a partial height of the link assembly. 
     According to a possible embodiment of the present invention, the ankle assisting exoskeleton device further includes a sleeve sleeved outside of the cable, wherein the cable can slide in the sleeve, an upper end of the sleeve is fixed to the actuator, and a lower end of the sleeve is connected to the lower limb support. 
     According to a possible embodiment of the present invention, the link assembly includes a support block that connects the pair of connecting rods with each other at a partial height of the link assembly, and the lower limb support further includes a sleeve base hinged to the support block, wherein the lower end of the sleeve is fixed to the sleeve base. 
     According to a possible embodiment of the present invention, the ankle assisting exoskeleton device further includes one or more sensors configured to detect the user&#39;s biological signal and the pulling force applied by the cable to the foot support in real time, the ankle assisting exoskeleton device further includes a controller configured to use a detected data from the sensors to control the pulling force applied by the cable to the foot support in real time. 
     According to a possible embodiment of the present invention, the actuator is provided with a roller around which the cable is wound, a motor configured to drive the roller to rotate, and a transmission that transmits power between the motor and the roller, and the ankle assisting exoskeleton device also includes a power supply configured to be worn in front of the user&#39;s waist for supplying power to various power-consuming components. 
     According to a possible embodiment of the present invention, the ankle assisting exoskeleton device includes an actuator, two independent lower limb supports that are configured to be worn on the user&#39;s left and right legs respectively, and two cables corresponding to the two lower limb supports respectively. 
     The present invention may be embodied as the schematic embodiments in the drawings. However, it should be noted that the drawings are only schematic, and any changes conceived under the teachings of the present invention should be considered to be included in the scope of the present invention, and the scope of the present invention is only delimited by the appended claims. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The drawings show several exemplary embodiments of the invention. These drawings should not be construed as necessarily limiting the scope of the invention. The same and/or similar reference signs throughout the text may refer to the same and/or similar elements, in which: 
         FIG. 1  is a schematic perspective view of an ankle assisting exoskeleton device worn on a user&#39;s lower limbs according to a possible embodiment of the present invention; 
         FIG. 2  is a schematic partial enlarged view of the ankle assisting exoskeleton device worn on the user&#39;s lower limbs shown in  FIG. 1 ; 
         FIG. 3  is a schematic exploded perspective view of the lower limb support of the ankle assisting exoskeleton device shown in  FIGS. 1 to 2 ; 
         FIG. 4  is a schematic diagram of the force applied to the lower limb support of the ankle assisting exoskeleton device shown in  FIGS. 1 to 3 ; and 
         FIG. 5  is a schematic exploded perspective view of the foot support of the lower limb support of the ankle assisting exoskeleton device shown in  FIGS. 1 to 3 ; 
         FIG. 6  shows the arrangement of sensors and microprocessors in the ankle assisting exoskeleton device shown in  FIGS. 1-3 . 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     The present invention will now be described in more detail with reference to the accompanying drawings, in which exemplary embodiments of the present invention are shown. However, the present invention can be implemented in many different forms and should not be construed as necessarily limited to the exemplary embodiments disclosed herein. On the contrary, these exemplary embodiments are only provided to illustrate the present invention and convey the concept of the present invention to those skilled in the art. 
       FIG. 1  is a schematic perspective view of an ankle assisting exoskeleton device worn on the lower limbs of a user according to a possible embodiment of the present invention.  FIG. 2  is a schematic partial enlarged view of the ankle assisting exoskeleton device worn on the lower limbs of the user shown in  FIG. 1 .  FIG. 3  is a schematic exploded perspective view of a lower limb support of the ankle assisting exoskeleton device shown in  FIGS. 1-2 .  FIG. 4  is a schematic diagram of the force applied to the lower limb support of the ankle assisting exoskeleton device shown in  FIGS. 1 to 3 .  FIG. 5  is a schematic exploded perspective view of a foot support of the lower limb support of the ankle assisting exoskeleton device shown in  FIGS. 1-3 .  FIG. 6  shows the arrangement of sensors and microprocessors in the ankle assisting exoskeleton device shown in  FIGS. 1-3 . In order to make the following description of the possible embodiments of the present invention easier to understand, in each view, the arrow ZZ′ indicates the vertical direction, the arrow YY′ indicates the front-to-rear direction, and the arrow XX&#39; indicates the transverse direction. The so-called front-rear direction YY′ can be understood as the front-rear direction with reference to the user wearing the ankle assisting exoskeleton device, which covers the front Y pointing in the direction that the user is facing towards and the back Y′ pointing in the direction that the user is facing away from. The so-called vertical direction ZZ′ can be understood as the height direction with reference to the user wearing the ankle assisting exoskeleton device, which covers the upper Z and the lower Z′. The so-called transverse direction XX&#39; can be understood as the left and right direction with reference to the user wearing the ankle assisting exoskeleton device, which covers the left direction X pointing in the left hand side of the user and the right direction X′ pointing in the right hand side of the user. In addition, any direction perpendicular to the vertical direction ZZ′ can be understood as a horizontal direction. It is worth noting that the above definition of orientation is only provided for the purpose of better describing the technical solution of the present invention, and should not be construed as a limitation to the present invention in any way. 
     With reference to  FIGS. 1 to 3 , the ankle assisting exoskeleton device according to the present invention includes: an actuator  100  configured to be worn behind the waist of a user; a lower limb support  200 ; and a cable  300  configured to controllably exert a pulling force to the lower limb support  200  when driven by the actuator  100 . Further, the lower limb support  200  includes: a calf ring (for example, made of knitted fabric)  210  configured to surround the user&#39;s calf; a foot support  230 , a front end  232  of the foot support  230  is configured to vertically clamp the user&#39;s foot, a rear end  231  of the foot support  230  is configured to be located behind the user&#39;s heel, and the rear end  231  is connected to the cable  300 ; a link assembly  220  disposed between the calf ring  210  and the foot support  230 , wherein an upper end of the link assembly  220  is attached to the calf ring  210  (for example, by a detachable hook and loop fastener, etc.), and a lower end of the link assembly  220  is hinged to the foot support  230  between the front end  232  and the rear end  231  of the foot support  230  (so that the foot support  230  can rotate about a transverse axis relative to the link assembly  220 ); a torsion spring  260  disposed between the lower end of the link assembly  220  and the foot support  230 , which is configured to apply a torque to the foot support  230  to lift the front end  232  upwards; and a sole pulling ring  250  hinged to the foot support  230  between the front end  232  and the rear end  231  of the foot support  230  (so that the sole pulling ring  250  can rotate about a transverse axis relative to the foot support  230 ), which is configured to pull (or hook) the user&#39;s sole (for example, the heel). 
     According to the above technical solution of the present invention, when the user wears the ankle assisting exoskeleton device according to the present invention, it only covers a small part (less than 25% of the limb surface area) of the user&#39;s limbs (especially joints), so it will not cause any restriction on the movement of the user&#39;s joints. In particular, the present ankle assisting exoskeleton device only partially covers the ankle joint that it assists without causing any constraints and obstacles to the other joints (such as the knee joint) that it does not assist, since the calf ring  210  is configured to surround the user&#39;s calf instead of the knee joint. Further, referring to  FIG. 4 , when the present ankle assisting exoskeleton device is working, the actuator  100  applies a pulling force F to the rear end  231  of the foot support  230  through the cable  300 , and the pulling force F applies a pulling torque to the foot support  230  to move the rear end  231  of the foot support  230  upwards and the front end  232  of the foot support  230  downwards; when the pulling torque is greater than the spring torque exerted by the torsion spring  260 , the rear end  231  exerts an upward pulling force F 2  (i.e., a normal force perpendicular to the skin surface of the sole) to the sole (in particular, the heel) through the sole pulling ring  250  so as to assist the ankle in plantar flexion (also known as plantar flexion) movement. It is worth mentioning that, the front end  232  will apply a force F 3  to the ground under the action of the pulling force F 2  instead of applying a relatively large force to the user&#39;s foot so as not to cause user&#39;s discomfort, since the user&#39;s forefoot abuts against the ground when performing a plantar flexion movement; when the pulling torque is less than the spring torque exerted by the torsion spring  260 , the front end  232  of the foot support  230  will apply an upward normal force F 3 ′ to the sole, which is perpendicular to the surface of the sole so as to assist the ankle in plantarflexion (also known as dorsiflexion) movement; and whenever the link assembly  220  will only receive a torque that makes it rotate around the foot support  230 , therefore, the link assembly  220  will only exert normal forces Fl, F 1 ′ to the user&#39;s calf, which are perpendicular to the skin surface of the calf, through the calf ring  210 , and this also allows the calf ring  210  to only partially contact the calf without tightly holding the calf, thereby improving the user&#39;s comfort. Therefore, the ankle assisting exoskeleton device will only generate normal forces F 1 , F 1 ′, F 2 , F 3 ′ perpendicular to the skin surface that are applied to the user&#39;s skin surface in contact during operation, and will not apply a tangential force to the user&#39;s skin surface in contact, which is tangential to the user&#39;s skin surface. Therefore, the ankle assisting exoskeleton device will not cause skin friction and tangential compression to cause discomfort to the user, and can provide sufficient assistance without being affected by the user&#39;s skin laxity and muscle strength. In addition, the normal forces F 1 , F 1 ′ are smaller and the assisting force F 3 ′ is larger, since the moment arm S 1  of the normal forces F 1  and F 1 ′ is larger, and the moment arm S 3  of the assisting force F 3 ′ is smaller. Therefore, the reaction force applied to the user&#39;s calf is relatively small, but the assisting force applied to the foot is relatively large, which further improves the comfort and effectiveness of the user when using the ankle assisting exoskeleton device for ankle assistance. 
     With reference to  FIGS. 1 to 3 and 5 , according to a possible embodiment of the present invention, the position where the sole pulling ring  250  is hinged to the foot support  230  is located between the position where the link assembly  220  is hinged to the foot support  230  and the rear end  231 . 
     With reference to  FIGS. 1 to 3 and 5 , according to a possible embodiment of the present invention, the foot support  230  includes a pair of support arms  233 ,  234  (i.e., the left side support arm  233  and the right side support arm  234 ) connecting the rear end  231  to the front end  232  on the left and right sides, wherein the front end  232  is constituted by support arm front ends  2331  and  2341  of the pair of support arms  233 ,  234  and an instep strap  235  attached thereto (for example, through detachable hook and loop fasteners, Velcro etc.), and the instep strap  235  is configured to partially cover the user&#39;s instep. 
     Therefore, referring to  FIG. 4 , according to the above-mentioned embodiment, when the pulling torque applied by the cable  300  is less than the spring torque applied by the torsion spring  260 , the support arm front ends  2331 ,  2341  will apply an upward normal force F 3 ′ to the sole, which is perpendicular to the surface of the sole, to assist the ankle in dorsiflexion movement. 
     Referring to  FIG. 5 , according to a possible embodiment of the present invention, the support arm front end  2331 ,  2341  of the pair of support arms  233 ,  234  include protrusions  2332 ,  2342  extending towards each other at their bottoms. 
     Therefore, referring to  FIG. 4 , according to the above embodiment, when the pulling torque applied by the cable  300  is less than the spring torque applied by the torsion spring  260 , the protrusions  2332 ,  2342  will apply an upward normal force F 3 ′ to the sole, which is perpendicular to the surface of the sole to assist the ankle in dorsiflexion (also known as dorsiflexion) movement, and it will not cause the user&#39;s sole&#39;s discomfort when the force F 3 ′ is large, since the protrusions  2332 ,  2342  are in surface contact with the user&#39;s sole. 
     Referring to  FIGS. 1 to 3 and 5 , according to a possible embodiment of the present invention, the pair of support arms  233 ,  234  together with the rear end  231  are U-shaped and configured to be horizontally (at least partially) surround the user&#39;s foot. 
     Referring to  FIG. 5 , according to a possible embodiment of the present invention, the pair of support arms  233 ,  234  include multiple sets of hinge holes, wherein each set of hinge holes include two hinge holes  2333 ,  2343  disposed in the pair of support arms  233 ,  234  oppositely in the transverse direction, and the sole pulling ring  250  is hinged to the pair of support arms  233 ,  234  at one set of the multiple sets of hinge holes. 
     Therefore, according to the above-mentioned embodiment, the position where the sole pulling ring  250  is hinged to the foot support  230  can be chosen from a variety of options to better match the user&#39;s foot, so that the ankle assisting exoskeleton device can assist users in a more efficient and more reliable manner. 
     Still referring to  FIG. 5 , according to a possible embodiment of the present invention, the pair of support arms  233 ,  234  include at least three sets of hinge holes. 
     Referring to  FIGS. 1 to 3 , according to a possible embodiment of the present invention, the link assembly  220  includes a pair of connecting rods  221 ,  222  (that is, the left connecting rod  221  and the right connecting rod  222 ) arranged on the left and right sides of the foot support  230 , each of the pair of connecting rods  221 ,  222  is respectively attached to the left and right sides of the calf ring  210  at its upper end, and respectively hinged to the foot support  230  at its lower end. Specifically, the left connecting rod  221  is hinged to the left support arm  233 , and the right connecting rod  222  is hinged to the right support arm  234 . 
     Therefore, according to the above embodiment, the calf ring  210  and the foot support  230  are only connected with each other through the pair of connecting rods  221 ,  222 , which greatly reduces the weight of the lower limb support  200  and further reduces the covered area of the user&#39;s limbs. Therefore, the physical exhaustion of the user when wearing the ankle assisting exoskeleton device is minimized, and the comfort is further improved. 
     Referring to  FIGS. 1 to 3 , according to a possible embodiment of the present invention, the link assembly  220  includes a support block  223  that connects the pair of connecting rods  221 ,  222  with each other along a part of the height of the link assembly  220 . Although it has been shown in the figure that the support block  223  connects the pair of connecting rods  221 ,  222  with each other at the middle of the link assembly  220  in the vertical direction, it is understandable that the position of the support block  223  in the vertical direction is variable, for example, it can be located above or below the middle of the link assembly  220  in the vertical direction. Therefore, any position of the support block  223  in the vertical direction should be regarded as included in the scope of the present invention. 
     Therefore, according to the above-mentioned embodiment, due to the existence of the support block  223 , the structure of the link assembly  220  is more stable and therefore can support the lower limb support  200  more reliably, and since the support block  223  is only located along a part of the height of the link assembly  220 , the support block  223  does not significantly increase the weight of the link assembly  220 . 
     Referring to  FIGS. 2 and 3 , according to a possible embodiment of the present invention, the ankle assisting exoskeleton device further includes a sleeve  400  sheathed outside the cable  300 , wherein the cable  300  can slide in the sleeve  400 , and the sleeve  400  is fixed to the actuator  100  at its upper end and connected to the lower limb support  200  at its lower end. In particular, the cable  300  and the sleeve  400  constitute a Bowden Cable. 
     Therefore, according to the above embodiment, the sleeve  400  can be used to guide the cable  300  between the actuator  100  and the lower limb support  200 , so that the actuator  100  can apply a pulling force to the lower limb support  200  through the cable  300  more efficiently and reliably. As a result, the ankle assisting exoskeleton device can provide users with assistive force in a more efficient and more reliable manner. 
     Referring to  FIGS. 2 and 3 , according to a possible embodiment of the present invention, the lower limb support  200  further includes a sleeve base  270  hinged to the support block  223 , so that the sleeve base  270  can rotate about a transverse axis relative to the support block  223 , wherein the lower end of the sleeve  400  is fixed to the sleeve base  270 . 
     Therefore, according to the above embodiment, the lower end of the sleeve  400  can rotate with the sleeve base  270  relative to the support block  223 , which makes the angular position of the lower end of the sleeve  400  varies with the movement of the user&#39;s foot. As a result, the direction in which the cable  300  exits from the lower end of the sleeve  400  is always directed towards the rear end  231  of the foot support  230  pulled by the cable  300 . In other words, the lower end of the sleeve  400  always guides the cable  300  towards the rear end  231  of the foot support  230  without imposing any obstruction in a direction transverse to that in which the cable  300  extends, so that the actuator  100  can apply a pulling force to the lower limb support  200  through the cable  300  more efficiently and reliably. As a result, the ankle assisting exoskeleton device can provide users with assistive force in a more efficient and more reliable manner. 
     According to a possible embodiment of the present invention, the ankle assisting exoskeleton device further includes one or more sensors (for example, IMU (Inertial Measurement Unit) sensors, EMG (electromyogram) sensors, force sensors, etc.), which are configured to detect user&#39;s biological signals (for example, foot movement, foot angle, foot acceleration, leg movement, leg angle, leg acceleration, muscle activity, etc.) in real time and the pulling force applied by the cable  300  to the foot support  200 . The ankle assisting exoskeleton device also includes a controller (for example, a microprocessor) configured to use the detection data from the sensors to control the pulling force applied by the cable  300  to the foot support  200  in real time. 
     Therefore, according to the above-mentioned embodiments, the present ankle assisting exoskeleton device uses sensors to detect the user&#39;s biological signals (for example, foot movement, foot angle, foot acceleration, leg movement, leg angle, leg acceleration, muscle activity and the like) in real time. Then, the controller can use the detected data to determine the movement mode that is and will be performed by the user (for example, the user is about to stand, walk, run, etc.) and the action that is and will be performed by the user&#39;s foot (for example, curvature movement, plantarflexion movement), and then the controller further uses the detected pulling force applied by the cable  300  to the foot support  200  to perform a closed-ring control of the pulling force so as to assist the user&#39;s ankle in real time, accurately and prospectively. Therefore, no matter what movement mode (for example, the user is about to stand, walk, run, etc.) that is and will be performed by the user and no matter what action (for example, curvature movement, plantarflexion movement) that is and will be performed by the user&#39;s foot, this ankle assisting exoskeleton device can assist the user&#39;s ankle in real time, accurately and prospectively. 
     Referring to  FIG. 6 , according to a possible embodiment of the present invention, the ankle assisting exoskeleton device includes an EMG sensor  610  arranged at the rear of the calf ring  210 , an IMU sensor  620  and a microprocessor  630  arranged in a support block  223 , a force sensor  640  arranged on the sleeve base  270  and an IMU sensor  650  arranged on the foot support  230 . In addition, the ankle assisting exoskeleton device further includes a circuit signal wire  500  configured to transmit data and power between the actuator  100  and the various sensors and the microprocessor. 
     Therefore, according to the above-mentioned embodiment, after the power is obtained from the actuator  100  through the circuit signal wire  500 , the EMG sensor  610  measures the biological signal of the user&#39;s calf, the IMU sensor  620  measures the inertial signal of the user&#39;s calf, the IMU sensor  650  measures the inertial signal of the user&#39;s foot, and the force sensor  640  measures the pulling force applied by the cable  300 . Then the microprocessor  630  can use the data output by the above-mentioned sensors to predict the user&#39;s actions and further control the pulling force applied by the cable  300  in a closed loop, so that the ankle assisting exoskeleton device can assist the user&#39;s ankle in real-time, precisely and prospectively. However, it is worth noting that the positions of the above-mentioned sensors and microprocessor are only exemplary, and their specific positions can be changed without affecting their functions. For example, the microprocessor  630  may be disposed in the actuator  100 , and the EMG sensor  610  may be disposed on the link assembly  220 . 
     According to a possible embodiment of the present invention, the actuator  100  is provided with a roller on which the cable  300  is wound, a motor configured to drive the roller to rotate and controlled by the controller, and a transmission for transmitting driving force between the motor and the roller. The ankle assisting exoskeleton device also includes a power supply configured to be worn in front of the user&#39;s waist for supplying power to various power-consuming components. 
     Therefore, according to the above-mentioned embodiments, the heavier components (for example, motor, power supply, transmission, etc.) of the ankle assisting exoskeleton device are all set on the waist of the user, that is, most weight of the ankle assisting exoskeleton device is concentrated on the user&#39;s waist instead of on the user&#39;s lower limbs. This further reduces physical exhaustion of the user when wearing the ankle assisting exoskeleton device, thereby improving the comfort of the user and allowing the user to be able to wear it for a long time to have the ankle assisted in movement; and since the power supply is located in front of the waist, and the motor, transmission, etc. are located behind the waist, the power supply, motor, transmission, etc. can be counterweight to each other, which further improves the comfort of the user when wearing the ankle assisting exoskeleton device. 
     Referring to  FIGS. 1 and 2 , according to a possible embodiment of the present invention, the ankle assisting exoskeleton device includes an actuator  100 , and two independent lower limb supports  200  that are configured to be respectively worn on the left and right legs of the user, and two cables  300  corresponding to the two lower limb supports  200  respectively. 
     Therefore, according to the above-mentioned embodiment, when one of the ankles of the user needs assistance, the user can wear only one lower limb support  200  to assist the ankle to exercise; when both ankles of the user need assistance, the user can wear two independent lower limb supports  200 .to simultaneously assist both ankles to exercise, which greatly improves the flexibility of the ankle assisting exoskeleton device in use. 
     The preferred but non-limiting embodiment of the ankle assisting exoskeleton device according to the present invention has been described in detail above with reference to the drawings. For those of ordinary skill in the art, it is obvious that modifications and additions to technologies and structures should be regarded as being included in the scope of the present invention without departing from the scope and essence of the present disclosure as set forth in the claims below. Therefore, these modifications and additions that can be conceived under the teaching of the present invention should be regarded as part of the present disclosure. The scope of the present disclosure is defined by the appended claims, and includes equivalent technologies known and those have not been foreseen at the filing date of the present disclosure.