Patent Application
20170209737
The present invention relates to the field of rehabilitation systems, more particularly to an upper limb rehabilitation system for rehabilitating the upper limb of a subject. The present invention further relates to an integrated rehabilitation platform that combines robotics and interactive gaming to enable individual undergoing rehabilitation to improve performance of coordinated movements of the shoulder, the forearm and the hand.
In the last 15 years, technological development has mainly focused on two kinds of rehabilitation systems: robotic systems and sensor based systems. Sensor based systems target to develop small portable devices enabling to monitor functional movement in natural settings like at home. However, only subjects with a certain level of strength can fully profit from sensor based systems. Robots on the other hand have shown to be able to facilitate repetitive training in stroke subjects with all functional levels which has proven to address brain plasticity improving sensorimotor function. Moreover, robotic systems, such as the MIT-Manus, the Haptic Master and the MIME, guarantee a large variability of goal-tailored training exercises which encourages subjects to use all their capabilities to improve their motor performances.
A recent review paper on rehabilitation technology advocates for a general improvement in short-term and long-term strength of upper limbs movements after training with robotics. Inversely, experimental evidence speaks against an improvement of the activity level. This might be because most rehabilitation systems support analytical training methods rather than task-oriented training. Indeed, studies using neuroimaging techniques have shown that functional recovery from stroke is positively affected by task-specific arm/hand sensorimotor input characterizing training or everyday use. Moreover, motor control studies have suggested that movements are planned as the combination of a relatively small number of muscle co-contraction patterns called synergies. Currently, only few systems are able to provide task-oriented exercises for the upper extremity. Of these systems, only ADLER allows for training of the entire arm and hand (but without an actuated hand gripping tool) and despite the MIT-MANUS team recently developed a hand module to complete the previous systems, this will not allow to train all joints of the upper limb at the same time. Another robotic system as disclosed in U.S.2008/0161733 allows three dimensional arm movements but not actuated and coordinated reaching-grasp movements.
Therefore, these solutions are still not offering the training of movement strategies as needed during real life arm-hand performance
U.S.2006/0106326 discloses wrist and upper extremity motion system which includes a series of motors that can apply torques to a wrist about the tree axes of wrist rotation: pronation/supination, flexion/extension, and adduction/abduction. In particular, the pronation/supination (PS) axis extends parallel to the longitudinal axis of the device. Rotation of the device about the PS axis will cause or result from pronation and supination of the subject's wrist and arm. The flexion/extension (FE) axis extends through the subject's wrist perpendicular to the PS axis. Rotation of the system about the FE axis will cause or result from flexion and extension of the subject's wrist. The abduction/adduction (AA) axis is perpendicular to the FE and PS axes and extends below the handle of the system. Rotation of the system about the AA axis will cause or result from abduction and adduction of the subject's wrist.
The configuration of this system is however mainly configured for the wrist rehabilitation of a subject. This system is therefore not adapted to simulate for example an interaction with a virtual object which is translating and rotating about an axis passing by its centre of gravity for training the hand and fingers' movements of the subject, thereby reducing the capability of the system to help retraining the whole functions of the impaired upper limb.
Accordingly, an aim of the present invention is to provide an upper limb rehabilitation system which is adapted to simulate a wide range of interactions with an object including reaching and grasping movements for training the hand and fingers' movements of a subject in order to help retraining the whole function of the impaired upper limb of the subject through an integrated robotic platform which overcome the above-mentioned main limitations of current robotic technology.
This aim and other advantages are achieved by an upper limb rehabilitation system for rehabilitating an upper limb of a subject and comprising a mobile platform coupled to a fixed platform. The mobile platform comprises an articulate handle assembly movable, during a rehabilitation session, within a plane which is substantially coplanar or parallel to the transverse plane of the subject wherein the handle assembly is provided with a gripping device comprising a shaft. The system according to the invention is characterized in that the articulate handle assembly comprises:
wherein said first and second axis of rotation as well as the central axis of the shaft of the gripping device always intersect at one point independently from the orientation of each of the first, second, third and fourth holding elements.
In one embodiment of the invention, the upper limb rehabilitation system is provided with motors. The position and orientation of the mobile platform is measured in relation to the fixed platform in six degrees of freedom. The force exerted by the subject against the mobile platform is also measured in said six degrees of freedom. The measured position and measured forced are forwarded to an controller interface and fed to a programmable computer which determines desired force feed-back to be applied by the controller interface to the mobile platform through the motors to assist and/or impede the movements of the subject. The programmable computer can also provide a virtual reality three-dimensional graphic simulation of exercises to simulate upper limb (i.e. shoulder, elbow, wrist and hand) movements of the subject, thereby providing sensory (e.g. visual, haptic) feedback to the user.
In one alternate embodiment of the invention, the motors of the rehabilitation system are substituted with brakes. In this configuration, the system cannot assist the movements of the subject but can still be used as a haptic interface by actuating the brakes to simulate a physical interaction with a virtual or augmented object.
Another aspect of the invention is to provide a method for the rehabilitation of an upper limb of a subject comprising the steps of (i) recording physiological signals of the subject such as electroencephalography (EEG), functional magnetic resonance imaging (fMRI), functional near-infrared spectroscopic imaging (fNRIS) or Electromyography (EMU) when the subject is operating the upper limb rehabilitation system, and (ii) interfering with the movements of said system in function of the recorded physiological signals.
The invention will be better understood thanks to the following detailed description of the invention with reference to the attached figures, in which:
An upper limb rehabilitation system, for improving performance of coordinated movements of an upper limb (i.e. shoulder, elbow, wrist, and hand, and fingers) of a subject, is described herein and is seen generally in
As particularly shown in
The handle assembly 10 comprises a first and a second holding element 14, 15 which have each a general -shaped construction and which are each oriented within a plane perpendicular to the plane of the supporting structure 50 on which the fixed platform 12 of the rehabilitation system is clamped. These first and second holding element 14, 15 are pivotally connected to a supporting structure which comprises a first and a second connecting link 13a, 13b which are both pivotally connected to the holding unit 12a of the fixed platform 12 to allow movements of the handle assembly 10 in two orthogonal directions within the working plane.
Referring to -shaped construction. The extremities of lower and upper parts of the third holding element 16 are pivotally connected to respective upper and lower parts of the
first and second holding elements 14, 15. The gripping device 11 is mounted on a shaft 18 whose extremities are rotatably mounted on opposite sides of the fourth-shaped holding element 17. The latter is pivotally connected to the third holding element 16 to rotate about a second axis of rotation θ2 perpendicular to the first axis of rotation θ1 within said third holding element 16 in order to allow forearm pronation movements and forearm supination movements of the subject through an angle up to +/−90 degrees as shown in
Turning now in particular to
The upper limb rehabilitation device according to the invention further comprises a forearm supporting structure 22 which is pivotally connected to handle assembly 10 to rest the subject's forearm, during a rehabilitation session, when operating the handle assembly 10 in the two orthogonal directions within the working plane as shown specifically in
According to one embodiment of the invention, the upper limb rehabilitation system as described above is adapted to provide active forces and/or torques to assist the subject's motions as well as resistive active movement in response to the subject motion to simulate the interaction with a virtual object. More specifically, the rehabilitation system according to this embodiment comprises two motors 30, 31 as shown in shaped holding element 16 as shown for example in
With reference to
According to this embodiment, the rehabilitation system can advantageously be used in an integrated robotic platform that combines robotics and interactive gaming to facilitate performance of task-specific repetitive, upper extremity/hand motor tasks, to enable individual undergoing rehabilitation to improve performance of coordinated movements of the forearm and hand. To this end, the robotic integrated platform comprises a gaming interface which is provided with a display device to simulate virtual reality and to present sensorimotor integration tasks to the subject. The rehabilitation device is used as a haptic interface to simulate the interaction with objects in a virtual reality world presented in the display device. Positions sensors (not shown) such as encoders or potentiometers are placed on the rehabilitation system on strategic locations to track the movement of the system. The integrated robotic platform further comprises a controller interface that is adapted to monitor and forward continuously, during the rehabilitation session, the outputs from the sensors to a programmable computer which determines desired force feedback to be applied by the controller interface to the corresponding motors 30, 31, 34 and 38 of rehabilitation system.
The level of assistance can be tuned on-line (e.g. during a working session) providing adapting time-dependent force fields. For example, given a specific task in which the subject has to follow a certain trajectory, the robotic platform can provide different level of support, from complete assistance, i.e. movements of the rehabilitation system are entirely driven by its motors, to full transparency, i.e. movements of the rehabilitation system are entirely caused by the subject upper limb's movements. The robotic platform can also provide force perturbation to increase the difficulty of the task.
The robotic integrated platform optionally comprises a controller arranged to monitor different physiological signals of the subject such as EEG or EMG and to drive the motors of the rehabilitation system for real time correlation between the movement of the device and brain activity pattern of the subject.
According to one alternate embodiment of the invention, the upper limb rehabilitation system as described above is adapted to provide resistive movements only, in response to the subject's motions. In this configuration, the motors are replaced by braking devices. For example, forearm pronation movements and forearm supination movements of the subject around the second axis of rotation 82 can be hindered by a braking device as shown in
The rehabilitation system according to the invention preferably comprises gravity compensation means that can provide different levels of gravity compensation either passively (i.e. counterweights or springs) or actively (i.e. motors).
As previously described, the rehabilitation system can advantageously be used in a robotic integrated platform that combines robotics and interactive gaming to facilitate performance of task-specific repetitive, upper extremity/hand motor tasks, to enable individual undergoing rehabilitation to improve performance of coordinated movements of the forearm and hand.
As shown in
Rehabilitation device 1602 also comprises a movement altering device 1610, which preferably alters a movement of mobile platform 1604. For example, movement altering device 1610 may optionally comprise a motor or a braking system, as described for example with regard to
Robotic integrated platform 1600 further comprises a controller interface 1612 for controlling movement altering device 1610, for example to induce a motorized and/or braking action. Controller interface 1612 is in turn controlled by a computational device 1614, which determines desired force feed-back to be applied by controller interface 1612 to mobile platform 1604 through movement altering device 1610 to assist and/or impede the movements of the subject.
Computational device 1614 also preferably features a VR (virtual reality) module 1616 for supporting three-dimensional graphic simulation of exercises to simulate the upper limb (i.e. shoulder, elbow, wrist, hand and fingers) movements of the subject, thereby providing sensory (e.g. visual, haptic) feedback to the user. Preferably robotic integrated platform 1600 also features a gaming interface 1618, comprising a display device 1620, to receive VR information from VR module 1616 and to display a VR environment to the subject. Display device 1620 may optionally comprise a VR headset for example (not shown).
It should be noted that although reference is made herein to “VR”, optionally the system and method as described herein could also relate to AR (augmented reality).
Rehabilitation device 1602 is preferably used as a haptic interface to simulate the interaction with objects in a virtual reality world presented in display device 1618. A position sensor 1620 is therefore also preferably placed on rehabilitation device 1602, to track movement of rehabilitation device 1602. Position sensor 1620 may optionally comprise a plurality of such sensors (not shown), and may optionally comprise one or more of encoders or potentiometers.
Computational device 1614 preferably controls a level of assistance or resistance to be provided to the subject through control of movement altering device 1610. The level of assistance can be tuned on-line (e.g. during a working session) providing adapting time-dependent force fields. For example, given a specific task in which the subject has to follow a certain trajectory, computational device 1614 may optionally determine that movement altering device 1610 is to provide different level of support, from complete assistance, i.e. movements of mobile platform 1604 are entirely driven by motors and the like, to full transparency, i.e. movements of mobile platform 1604 are entirely caused by the subject's upper limb movements. A level of resistance may also optionally be determined by movement altering device 1610, for example by providing force perturbation to increase the difficulty of the task.
In stage 1, a user, such as the subject or a separate operator, interfaces with a user input of the computational device to select an exercise from a library of exercises which may be stored. In this example a ‘reach an object exercise’ is selected. At this stage the user may optionally be provided with the results of previously performed exercises. These results may be provided to aid in the selection of the particular exercise or exercise difficulty. The user may also input parameters to adjust the difficulty of the exercise, for example based on a level of success from the previous exercise.
At stage 2, the computational device initializes the exercise, for example by sending commands to the VR module to set up the VR environment, and also preferably by initializing the rehabilitation device. For example, the computational device may optionally initialize the movement altering device, to cause an initial amount of resistance to be applied to the mobile platform. Also optionally, one or more body parts of the subject are tracked, in order for the VR environment to appear more realistic. Alternatively, or in addition, to such tracking, the upper limb to be rehabilitated may optionally be modeled according to interactions with the mobile platform, for example from the previously described positional sensor(s).
Initialization may also optionally include mapping the movements of the subject into the VR environment.
In stage 3, the exercise begins, with the subject in physical communication with the mobile platform, and also optionally and preferably wearing a VR headset or the like, to be able to see and interact with the VR environment. The subject may optionally be asked to move his/her arm toward a virtual object, for example
The computational device receives data regarding such movement, for example from the previously described positional sensor(s), in stage 4. In stage 5, the computational device preferably determines whether to increase or decrease resistance or assistance, according to the received data. Such an increase or decrease could optionally be used for example to simulate interactions with objects whose physical properties (e.g. stiffness, roughness, etc) are simulated through the upper limb rehabilitation system. Optionally other types of haptic feedback may be incorporated as well, for example with regard to temperature.
In stage 6, the computational device optionally adjusts resistance or assistance, through communication with the controller interface. In stage 7, the controller interface communicates with the movement altering device to perform the adjustment.
In stage 8, optionally the subject receives visual feedback concerning his/her own movements, for example through the projection of an avatar replicating his/her movements in the VR environment according to one or more commands from the VR module to the VR display device. Optionally the visual and haptic feedback is coordinated, such that the subject experiences both in real time.
In stage 9, the VR environment is preferably updated with regard to the effect of movement of the mobile platform, in terms of movement parameters such as trajectories, velocities, accelerations and forces.
Robotic integrated platform 1800 optionally further comprises a physiological monitor 1802 arranged to monitor different physiological signals of the subject, and to provide information to drive the actions of movement altering device 1610 for real time correlation between the movement of mobile platform 1604 and brain activity pattern of the subject. Physiological monitor 1802 is connected to a physiological sensor 1804 in order to monitor different physiological signals of the subject. Physiological sensor 1804 optionally comprises one or more of electroencephalogram (EEG) sensors, Electromyogram (EMG) sensors, Electrooculography (EOG) sensors, Electrocardiogram (ECG) sensors, functional magnetic resonance imaging (fMRI), functional near-infrared spectroscopic imaging (fNRIS), or skin conductance sensor.
Physiological monitor 1802 in turn communicates with computational device 1614, to provide the physiological sensor data. Computational device 1614 optionally uses the physiological sensor data in order to update the VR environment and/or to control controller interface 1612, in order to increase or reduce assistance or resistance to movements of the subject through rehabilitation device 1602. For example, computational device 1614 may optionally control the movements of rehabilitation device 1602, additionally or alternatively, in regard to input from the physiological, brain or movement signals.
While the invention has been described with respect to a limited number of embodiments, it will be appreciated that many variations, modifications and other applications of the invention may be made, including different combinations of various embodiments and sub-embodiments, even if not specifically described herein.
| Number | Date | Country | Kind |
|---|---|---|---|
| 14180356.9 | Aug 2014 | EP | regional |
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/EP2015/068104 | Aug 2015 | US |
| Child | 15426443 | US |
