DE202013002572U1 - Reconfigurable ankle exoskeleton device - Google Patents

Abstract

An unguided, portable and reconfigurable exoskeleton apparatus for ankle therapy and measurement, comprising: a base platform facing the leg of the user, a movement platform facing the foot of the user; a link connecting the base platform and the motion platform, a link connecting the link to the base platform.

Description

Background of the invention

The present invention relates to a non-grounded reconfigurable parallel mechanism force feedback exoskeleton device for the human ankle. The device is mainly used as a balance / proprioception trainer, although the exoskeleton device may also be used for RoM / Strengthening (RoM) exercises. This device is also used for metatarsophalangeal joint exercises.

The goal of rehabilitation is to restore a patient's physical, sensory and neuronal abilities that have been compromised as a result of illness or injury. Ankle rehabilitation is usually necessary after ankle sprain, one of the most common injuries in sports and daily life [1]. Loss of function, ability to support weight and ankle joint stability also occur after neurological injury as a secondary consequence of stroke and contracture deformation as a secondary consequence of cerebrovascular disease. Physiotherapeutic exercises are essential for restoring the range of motion (ROM) of the joint, helping to re-enforce muscles for carrying weight, promoting better perception of joint position (proprioception), assuring nerve integrity, and regaining the dynamic balance.

Rehabilitation of an ankle injury is commonly addressed in three consecutive exercise phases [2], [3]. Exercises in the early phase focus first on allowing a full ROM of the joint, and then strengthening ankle muscles. Once the required RoM and mobility is achieved and the muscles have become strong enough to partially support weight without causing pain, the middle therapy phase can be started focusing on enhancing propioceptor ability through the use of static balance exercises. In the final stages of therapy, more demanding dynamic balance exercises are performed.

Conventional rehabilitation devices used to assist physiotherapy are simple passive devices such as elastic ligaments and ankle rehabilitation shoes for strengthening and stretching exercises; Rattling boards and foam rollers for proprioception and balance exercises. RoM exercises are generally performed manually by a therapist. While these types of devices are simple and fixed cost effective, these conventional devices lack the ability to collect quantitative measurements of patient progress, monitor patient history for reassessment, and gain individual interactive treatment protocols. Therapists are required to wear body-load of exercise therapy while practicing with these devices and to pay their full attention to the patient.

Today, rehabilitation exercises are performed using robotic devices. Assisting repetitive and physical rehabilitation exercises using robotic devices not only helps to eliminate the physical burden of exercise therapy for the therapist, but also reduces the cost associated with the application. In addition, robot-mediated rehabilitation therapy allows for quantitative measurements of patient progress and can be used to realize individual interactive treatment protocols.

Beneficial effects of protocols of robot assisted rehabilitation have been demonstrated in comparison to conventional therapy through clinical trials in the literature [4]. Recognizing the need for robotic rehabilitation devices for ankle physiotherapy, various designs have been proposed to date. Girone et al. proposed a Stewart platform based force feedback interface called "Rutgers Ankle" (Rutgers Ankle) [5]. In [6], a virtual reality-based interactive training protocol using the "Rutgers Ankle" for orthopedic rehabilitation has been implemented. The system has been further investigated by several case studies [7] and [8]. Home ankle telehabilitation was addressed in [9], while in [10] the system was expanded to a dual Stewart platform configuration to be used for gait simulation and rehabilitation.

In [11] beat Dai et al. another robotic device to treat compressed ankle injuries. Unlike the Stewart platform design, this device advances just enough degrees of freedom (DoF) to cover the human ankle orientation space. The kinetostatic analysis presented in this reference emphasized the importance of using a central strut to achieve greater rigidity from to the device. In [12] beat Agrawal et al. Ankle Ankle Orthosis for robot assisted rehabilitation and presented the kinematic analysis and control of the proposed mechanism. Likewise, in [13] anklebot von Roy et al. proposed to promote recovery of the footbone function. This device can also be used to measure ankle stiffness, which is an important biomechanical factor for locomotion.

Syrseloudis and Emiris studied the translation and rotation of the human ankle and foot by experimenting with human subjects and concluded that a parallel tripod mechanism with an additional axis of rotation in series is the most relevant kinematic construction that most closely matches the foot ankle mechanism associated with the human ankle [14 ]. In [15] beat Yoon and Ryu presented a hybrid, four-degree-of-freedom (DoF) foot-pad device based on a parallel mechanism and presented the kinematic analysis of the new device. In [3] and [16] this work has been extended to allow reconfiguration of the device to support several different exercise modes.

It is therefore an object of the invention to provide a device having a reconfigurable construction. Their implementation is simple and the device can be made by assembling commercially available parts. Due to its reconfigurability, the device allows both range of motion / strengthening exercises as well as balance / proprioception exercises.

Summary of the invention

According to one embodiment of the present invention, the device is capable of covering the entire complex area of the human ankle for RoM / Strengthening exercises. The device can support human weight during balance / proprioception exercises. The reconfigurable construction of the base plate also allows exercises for the metatarsophalangeal joint.

According to one embodiment of the present invention, the device may be used as a clinical measurement tool. Ankle joint range of motion, forces and impedances can be detected to aid diagnoses.

According to one embodiment of the present invention, the device is ergonomic, allowing the entire range of motion of the human ankle. The device is lightweight and portable; thus transportable. The device is inherently safe due to the selected actuators.

According to one embodiment of the present invention, the device has a higher control capability than similar devices because of its parallel kinematic structure and optimized bandwidth.

According to one embodiment of the present invention, the device supports complex movements of the foot and is not limited to a single degree of freedom, as is the case with many existing designs.

In accordance with one embodiment of the present invention, the device is programmed to guide, assist, or resist the patient during physical therapy and is implemented with a computer system. The assistant and resistance levels are adjustable via software. The device may also be programmed to estimate ankle parameters, such as ankle tone and impedance.

Aspects of the device according to the present invention relate to rehabilitation robots, robot assisted rehabilitation, physical therapy devices, force feedback exoskeletons, haptic interface devices for medical treatment, clinical measurement devices, ankle rehabilitation systems, ankle orthosis, ankle rehabilitation devices, devices for assessing ankle function, ankle impedance determination ,

Brief description of the drawings

1 is a perspective view of the device;

2 Figure 3 is a side view of the device in 3UPS configuration;

3 Figure 3 is a perspective view of the device when acting as a 3RPS mechanism;

4 Figure 3 is a perspective view of the device when acting as a 3UPS mechanism (the middle limb represents the human foot and ankle);

5 is a perspective view of a hinge element used in the device in the unlocked position;

6 is a perspective view of the hinge element used in the device in the locked position;

7 Figure 10 is a block diagram of the robust position controller with reaction torque observer.

Detailed Description of the Preferred Embodiments

The following description of the preferred embodiment is merely exemplary in nature and is in no sense intended to limit the invention, its application, or uses.

An exoskeleton device for ankle therapy and measurement ( 1 ) indicates:
a motion platform ( 2 ), which is opposite the foot of the user,
a base platform ( 3 ), which is opposite to the leg of the user,
a connecting element ( 4 ), which is the base platform ( 3 ) and the motion platform ( 2 ) connects.

The exoskeleton device ( 1 ) also has a hinge element ( 5 ), which is the connecting element ( 4 ) with the base platform ( 3 ) connects. Using the joint element ( 5 ), the exoskeleton device ( 1 ) support two different exercise types independently, namely RoM / Strengthening Exercises and Balance / Proprioception Exercises. The joint element ( 5 ) can be selectively in different modes. In the preferred embodiment of the invention, it can be switched between a universal joint and a pressure joint.

In the preferred embodiment of the invention, the connecting element ( 4 ) using ball joints with the motion platform ( 2 ) connected.

An ankle joint can be modeled as a two-thrust (RR) serial serial kinematic chain, an upper pressure joint and a subtalar joint. The upper ankle joint supports dorsiflexion / plantarflexion rotation, while the subtalar joint supports supination / pronation rotation. The supination / pronation rotation is a complex movement that has both inversion / eversion and abduction / adduction components.

The kinematic chain used in the preferred embodiment of the invention is the closed kinematic chain (parallel mechanism). The closed kinematic chain serves as an exoskeleton and allows and supports the natural movements of human joints when the user 1 ) in itself. A closed kinematic chain provides the compact constructions with high rigidity and has a low effective inertia. The actuators of the closed kinematic chains may be grounded or placed on parts of the mechanism which is subject to low accelerations.

The closed kinematic chain used in this invention can by means of the joint element ( 5 ) are used as at least two different mechanisms. With this fact, the device gets ( 1 ) a reconfigurable property. In the preferred embodiment of the invention, it can be used as a 3UPS mechanism (universal, prismatic, spherical) and 3RPS mechanism (rotating, prismatic, spherical) independently of each other.

In the preferred embodiment of the invention, the joint element ( 5 ) the reconfigurable joint, which can be selectively used in unlocked or locked position. In the unlocked position, the reconfigurable joint ( 5 ) rotate freely around two axes (A, B). The first axis (A) is tangential to the base plate ( 3 ), while the second axis (B) perpendicular to the base plate ( 3 ). When the joint ( 5 ), series hinges act as a universal joint rotating about desired ones of the axes. When the second hinge axis (B) is locked, the reconfigurable joint ( 5 ) limited to the function of a rotary joint, which is freely rotatable only about the first axis (A). Thus, the reconfigurable joint ( 5 ) a reconfiguration of a 3UPS mechanism into a 3RPS mechanism and vice versa.

The connecting element ( 4 ) essentially comprises a drive unit ( 6 ) and a movement element ( 7 ) on. The drive unit ( 6 ), the required force on the moving element ( 7 ), so that the movement element ( 7 ) can move. In the preferred embodiment of the invention, the drive unit ( 6 ) an electric motor, while the moving element ( 7 ) is at least one extendable member.

In the case that the closed kinematic chain is used as a 3UPS-mechsmnism, the reconfigurable joint ( 5 ) in unlocked position, in other words, it is freely rotatable about desired axes (A, B) behaves like a universal joint. In addition, the leg of the user behaves as a central member of the mechanism, in other words, the ankle of the user becomes a member of the mechanism. In the preferred embodiment of the invention, the mechanism is a symmetrical 3UPS mechanism in which the universal joint ( 5 ) and the ball joints at a distance of 120 ° along the circumference of the base platform ( 3 ) and the motion platform ( 2 ) are arranged. Worn by the user the 3UPS mechanism attached to the human ankle has two degrees of freedom (DoF) corresponding to a coupled motion platform motion (FIG. 2 ) with respect to the stationary base platform ( 3 ). The lengths of the extendable links ( 7 ) are pressed to control this DoF. The motion platform ( 2 ) is at a distance z from the base platform ( 3 ) and has no translation movement transversal to the vertical axis through the base ( 2 ). Even if the user is completely passive, the 2-DoF-3UPS mechanism has three actuated joints; So it's a redundant mechanism. This redundancy can be exploited to increase the effective working space of the device ( 1 ), since singularity resolution becomes possible in the case where the device ( 1 ) approaches singularities within the workspace.

In the case that the closed kinematic chain is used as a 3RPS mechanism, the reconfigurable joint is ( 5 ) in the locked position, in other words, the rotational movement of the joint ( 5 ) about the second axis (B) is prevented. The reconfigurable joint ( 5 ) behaves as a hinge and its axes of rotation are along the tangents of the base platform ( 3 ). The base platform ( 3 ) is attached to the upper mid-calf of the leg by a passive swivel joint to allow the inner / outer rotations of the foot. In the preferred embodiment of the invention, the mechanism is a 3RPS symmetric mechanism in which the hinges ( 5 ) and the ball joints at a distance of 120 ° along the circumference of the base platform ( 3 ) and the motion platform ( 2 ) are arranged. The 3RPS mechanism has three DoFs according to the height z. The lengths of the extendable links ( 7 ) are pressed to control this DoF. The motion platform ( 2 ) has limited translational movement transversal to the vertical axis through the base ( 3 ) and no singularities for limited values of hinge angle.

If the closed kinematic chain is in the 3UPS mode, the device may ( 1 ) can be used as a RoM / strengthening exercise device while in the 3RPS mode they ( 1 ) can be used as a balance / proprioception training device.

Couplings between the exoskeleton device ( 1 ) and the user are elastically constructed to ensure safety and allow for small joint misalignments and model defects. Elasticity allows the relative movement of the human limb relative to the device ( 1 ), if the kinematics of the device ( 1 ) is in conflict with the natural motion of the ankle.

In one embodiment of the invention, using tight straps around the knee, the weight of the device ( 1 ) over the upper leg and lower mid-calf.

In another embodiment of the invention, by suspending the device ( 1 ) on the shoulder of the user the weight of the device ( 1 ) are distributed over the body.

The exoskeleton device ( 1 ) also has a control unit (not shown in the figures) and at least two sensors (not shown in the figures). One of the sensors measures the length of the connecting element ( 4 ), while the second sensor measures the extent of axial rotation of the joint element (FIG. 5 ) measures. The measured data of the elements are processed by the control unit to determine the configuration of the device ( 1 ) and those on them ( 1 ) to estimate acting forces. In particular, a forward kinematics of the device ( 1 ) used to configure the motion platform ( 2 ) while the dynamics of the device ( 1 ) is used with a software implemented reaction torque observer in order to 1 ) to estimate acting forces.

To estimate the ankle parameters, the lengths of the limbs ( 7 ) of the kinematic chain to be known together with the axes of rotation of the swivel joints. Determining the bone length of the user is relatively easy because x-ray images of the ankle can be evaluated to get fairly accurate estimates. Determining the axes of rotation, however, is difficult because the motion of the ankle depends on the size and orientation of the foot bones and the shape of the articular surfaces. By evaluating the X-ray images only rough estimates of the joint axes can be obtained. To study the ankle movement, more accurate estimates of the articulation axes are desired, and such estimates are made possible thanks to the data collected with the exoskeleton.

With good bone length estimates, the rotational axes of the human ankle pivot joints can be determined by instructing the user to perform free RoM movements and by taking positional data from the telescoping members (FIG. 7 ) and preferably three on the joint element ( 5 ) arranged rotational sensors are collected. As the data becomes available, the configuration extent forward kinematics of the 3UPS mechanism for the motion platform configurations (FIG. 2 ) solved at any time. Once the foot configurations are recorded, the Configuration scale inverse kinematics of the two limb RR manipulator with unknown pivot axes (representing the human ankle) for the axes of the pivots and the extent of rotation around these axes.

Are the configuration and range of motion of forward and inverse kinematics of the coupled 3UPS RR system (the exoskeleton coupled with the human ankle) and the dynamic properties of only the exoskeletal apparatus ( 1 ), a robust position controller can be implemented with a reaction torque observer to characterize the dynamic properties of the ankle. In particular, the exoskeleton device ( 1 ) using a robust position controller to control the ankle to follow a desired trajectory while at the same time estimating disturbance forces due to the unknown dynamics of the ankle during this movement. In the controller implementation, forces are attributed to the known dynamics of the exoskeleton ( 1 ) are added to the system in an input-forward manner to ensure that the system-related disturbance is solely due to the unknown ankle dynamics. Under such control, the forces controlled by the controller should compensate for the unmodeled dynamics of the ankle. Therefore, the actuator forces can be correlated with the joint torques at the ankle, and assuming that all other disturbances are relatively small, these torques provide a good estimate of the actual joint torques due to joint dynamics.

The exoskeleton device ( 1 ) can provide passive, active, assistance and resistance practice modes. Virtual tunnels and force fields within these tunnels can be implemented to enable safe practice with assistance or resistance.

Since the device ( 1 ) in the 3UPS configuration allows all possible movements of the ankle in full, it is possible to use the device ( 1 ) for clinical measurements. Primarily, the device can be used to determine the range of motion of the patient. As the patient moves his / her ankle, the device can measure and record the time history of that movement (the trajectory). With the given time history of movements, it is possible to determine how fast the patient is performing a movement, the size of the error with respect to a reference trajectory, and how even / uneven these movements are. Since the kinematics of the device ( 1 ), it is also possible to correlate the measured configuration changes with the rotations of the ankle joint. This capability allows measurements of orientation, speed and uniformity of ankle joint movement. Coordination and synergy of joint movements can also be obtained from these measurements.

As explained above, by using a robust position controller and by controlling the exoskeleton device ( 1 ) to follow a desired trajectory, the disturbance forces due to the unknown dynamics of the ankle. be appreciated during this movement. Using ankle kinematic techniques, these forces can also be correlated with the joint torques at the ankle. This measurement technique can be used to determine maximum joint torques that the patient can exert, the impedance and tone of the patient's ankle in any configuration of the ankle. In particular, if the robust position controller's gain is set to remain in any reference configuration and the patient is asked to apply maximum torque to his / her ankle joints, then the disturbing forces acting on the controller may be correlated are using joint torques to estimate torques of the human ankle around the corresponding axes. Finally, given a predetermined reference trajectory for the robust position controller, the joint torques can be estimated at each instant, and the relationship between joint rotation and joint torques can be used to estimate the impedance and / or tone of the ankle.

In another embodiment of the invention, the non-grounded, portable and reconfigurable ankle therapy / measurement exoskeleton device may be combined with virtual reality games.

The description of the invention is merely exemplary in nature and, therefore, modifications which do not depart from the gist of the invention are intended to be within the scope of the invention. Such modifications are not to be regarded as a departure from the spirit and scope of the invention.

bibliography

• [1] H. Tropp and H. Alaranta, Sports Injuries: Basic Principles of Prevention and Care, Proprioception and Coordination Training in Injury Prevention, Oxford 1993 ,
• [2] D. Hung, M. Kennedy, A. Rowland, JD Purdy, and M. Yampolsky, "Ankle Rehabilitation: Evidence-based Approach," Vanderbilt Rehabilitation Services ,
• [3] J. Yoon, J. Ryu and K. Lim, "A novel reconfigurable ankle rehabilitation robot for various exercise modes," Journal of Robotic Systems, Vol. 22, No. 1, pp. 15-33, 2006 ,
• [4] R. Ekkelenkamp, P. Veltink, S. Stramigioli, and H. van der Kooij, "Evaluation of a Virtual Model Control for the Selective Support of Gap Functions Using Exoskeleton," Rehabilitation Robotics, 2007. ICORR2007. IEEE 10th International Conference on, pp. 693-699, June 2007 ,
• [5] M. Girone, G. Burdea, and M. Bouzit, "The Rutgers Ankle Orthopedic Rehabilitation Interface," in Proceedings of the ASME Haptics Symposium, Vol. 67, 1999, p. 305-312 ,
• [6] M. Girone, G. Burdea and M. Bouzit, V. Popescu and J. Deutsch, "Orthopedic rehabilitation using the Rutgers Ankle Interface," in Proceedings of Virtual Reality Meets Medicine 2000, pp. 89-95 ,
• [7] JE Deutsch, J. Latonio, G. Burdea, and R. Boian, "Rehabilitation of musculoskeletal injuries using the Rutgers ankle haptic interface: Three case reports," in Proceedings of Eurohaptics 2001, 1-4 July 2001, p. 93-98 ,
• [8th] JE German, J. Latonio, GC Burdea, and R. Boian, "Post-stroke rehabilitation with the Rutgers ankle system: A case study," Presence: Teleoper. Virtual Environ., Vol. 10, No. 4, pp. 416 ^ 130, 2001 ,
• [9] M. Girone, G. Burdea, M. Bouzit, V. Popescu, and JE Deutsch, "A Stewart Platform-based System for Ankle Telehabilitation," Autonomous Robots, Vol. 10, No. 2, pp. 203-212, 2001 ,
• [10] RF Boian, M. Bouzit, GC Burdea, J. Lewis, and JE German, "Dual Stewart platform mobility simulator," in Proceedings of the ICORR 2005, 9th International Conference on Rehabilitation Robotics, 2005, pp. 550-555 ,
• [11] JS Dai, T. Zhao and C. Nester, "Sprained ankle physiotherapy-based mechanism synthesis and stiffness analysis of a robotic rehabilitation device." Auton. Robots, Vol. 16, No. 2, pp. 207-218, 2004 ,
• [12] A. Agrawal, S. Banala, S. Agrawal and S. Binder-Macleod, "Design of a two degree-of-freedom ankle-foot orthosis for robotic rehabilitation," Rehabilitation Robotics, 2005. ICORR 2005. 9th International Conference on , pp. 41-44, June - 1 July 2005 ,
• [13] A. Roy, H. Krebs, S. Patterson, T.Judkins, I. Khanna, L. Forrester, R. Macko, and N. Hogan, "Measurement of Human Ankle Stiffness Using the Anklebot," Rehabilitation Robotics, 2007. ICORR 2007 IEEE 10th International Conference on, pp. 356-363, June 2007 ,
• [14] CE Syrseloudis, IZ Emiris, CN Maganaris, and TE Lilas, "Design Framework for a Simple Robotic Ankle Evaluation and Rehabilitation Device," Engineering in Medicine and Biology Society, 2008. EMBS 2008. 30th Annual International Conference of the IEEE, pp. 39-35. 4310-4313, Aug. 2008 ,
• [15] J. Yoon and J. Ryu, "A new family of hybrid 4-DoF parallel mechanisms with two platforms and its application to a footpad device," Journal of Robotic Systems, Vol. 22, No. 5, pp. 287-298, 2005 ,
• [16] -, "A novel reconfigurable ankle / foot rehabilitation robot," Robotics and Automation, 2005. ICRA 2005. Proceedings of the 2005 IEEE International Conference on, pp. 4 2290-2295, April 2005 ,

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited non-patent literature

• Girone et al. [0006]
• Dai et al. [0007]
• Agrawal et al. [0007]
• Roy et al. [0007]
• Syrseloudis and Emiris [0008]
• Yoon and Ryu [0008]

Claims (16)

Non-ground, portable and reconfigurable exoskeleton device for ankle therapy and measurement comprising: a base platform opposite the leg of the user, a motion platform opposite the foot of the user; a connector that connects the base platform and the motion platform, a hinge member connecting the connector to the base platform. An unguided exoskeleton apparatus for ankle therapy and measurement according to claim 1, characterized in that the exoskeleton apparatus can independently support two different exercise types, namely, strengthening exercises range of motion and balance / proprioception exercises. The unguided exoskeleton apparatus for ankle therapy and measurement of claim 1 and 2, characterized in that the articulation member is a reconfigurable joint, the reconfigurable joint being free to rotate about two axes in the unlocked position, the first axis being tangent to the baseplate, while the second axis is perpendicular to the base plate. An unguided exoskeleton apparatus for ankle therapy and measurement according to claim 3, characterized in that, when the reconfigurable joint is unlocked, a series of hinges function as a universal joint rotating about desired ones of the axes. The unguided exoskeleton for ankle therapy and measurement according to claim 3, characterized in that, when the second articulation axis is locked, the reconfigurable articulation is restricted to the function of a pivot freely rotatable only about the first axis. An unguided exoskeleton apparatus for ankle therapy and measurement according to any one of the preceding claims, characterized in that the reconfigurable joint permits a 3UPS mechanism in which the device is used as a RoM / strengthening exercise device in a 3RPS mechanism which the device is used as a balance / proprioception exerciser, and vice versa. An unguided outer ankle apparatus for ankle therapy and measurement according to claim 6, characterized in that, when the device is used as a 3UPS mechanism, the reconfigurable joint is in unlocked position and behaves like a universal joint and the user's leg is median Limbs of the mechanism behaves. An unguided exoskeleton apparatus for ankle therapy and measurement according to claim 6, characterized in that, when the device is used as a 3RPS mechanism, the reconfigurable joint is in the locked position and behaving like a hinge and its axes of rotation along the tangents of the base platform are oriented. An unguided exoskeleton device for ankle therapy and measurement according to any one of the preceding claims, characterized in that the connecting element comprises a drive unit and a movement element. An unguided exoskeleton apparatus for ankle therapy and measurement according to any one of the preceding claims, further comprising a control unit and at least two sensors. An unguided exoskeleton apparatus for ankle therapy and measurement according to any one of the preceding claims, characterized in that the apparatus can provide passive, active, assistance and resistance exercise modes. The unguided exoskeleton apparatus for ankle therapy and measurement according to claim 11, characterized in that virtual tunnels and force fields within said tunnels are implemented to the apparatus to allow safe practice with assistance and resistance modes. An unguided exoskeleton device for ankle therapy and measurement according to claim 12 in combination with the virtual reality games. An unguided exoskeleton apparatus for ankle therapy and measurement according to any of the preceding claims, further comprising a robust position controller with torque monitors. Use of an unguided exoskeleton apparatus for ankle therapy and measurement according to any of claims 10 to 14 for performing clinical measurements. The unguided exoskeleton apparatus for ankle therapy and measurement according to claim 15, characterized in that the device performs the following measurements: joint configuration, movement speed, trajectory, trajectory error, motion uniformity, range of motion, coordination and synergies, maximum Joint torques in each configuration, joint torques while tracking a trajectory, tone and impedance of the ankle.

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