FR3148908A1 - Body part rehabilitation system with haptic device - Google Patents

Abstract

The present invention relates to a rehabilitation assistance system (100), comprising at least one haptic device (110), a motion capture device (120), control electronics (130) and a software application, said control electronics (130) communicating with said haptic device (110) and said application communicating with said control electronics (130) and said capture device (120) so as to obtain a first data item representative of an ideal trajectory and a second data item representative of a movement of a user (3), compare said movement with said trajectory, determine instructions for applying force feedback to said haptic device (110) and transmit said instructions to said control electronics (130). Figure for abstract: Figure 1

Description

Body part rehabilitation system with haptic device

The present invention relates to the field of medical devices and systems.

The present invention relates more particularly to a system for rehabilitating a part of a user's body, stimulating the sensory capacities of a user by the use of haptic devices.

By rehabilitation within the meaning of the present invention, is meant throughout the description which follows the methods of facilitating the execution of tasks, in particular the performance of correct movements, in users suffering from a physical handicap.

The present invention will thus find numerous advantageous applications in the fields of physiotherapy and occupational therapy, in particular in assisting the development of muscular functions.

State of the art

The loosening of neural connections and transmissions between the brain and different parts of the body has serious consequences over time. This can have a significant impact on the level of disability. Motor impairments in the upper and lower limbs are common in these people. These disabilities occur due to the loss of communication between the brain and the affected side of the body, for example due to a Cerebrovascular Accident, known as a stroke.

One year after the onset of the first stroke, physical independence (for 66% of stroke survivors) and occupation (for 75% of stroke survivors) are the most affected areas of disability.

This requires multidisciplinary rehabilitation of stroke patients, which aims to reduce the consequences of the disease in daily functioning. Occupational therapy aims to facilitate task performance by improving relevant performance skills or developing and teaching compensatory strategies to overcome lost performance skills.

Self-care training, leisure activity training, and assistive device advice and instruction are the three most commonly chosen interventions for stroke patients.

Various interventions (e.g., helping the upper limbs perform correct movements such as reaching for touch) are performed by therapists in hospitals or their clinics. This occupational therapy typically involves repeating specific movements, and therapists' schedules may interfere with intensive rehabilitation programs for patients. The high cost of this type of therapy limits the number of patients who benefit and decreases the potential for success. The repetitive nature of physical therapy exercise limits the overall duration. Thus, providing exercises with increased interest and challenge may attract the patient's attention and increase the time spent in therapy.

Virtual reality therapy is one of the methods used for rehabilitation. The main goal of using virtual reality in therapy is to increase the level of patient engagement in rehabilitation processes as well as motivate patients to do more and increase the time spent in rehabilitation. Virtual reality in therapies is classified as repetitive and objective therapy. Virtual reality scenes have been used in therapy mainly as stimulating and motivated environments for therapy; they are oriented to facilitate the training of repetitive movements for individuals.

The Applicant submits, however, that virtual reality scenes are currently restricted to visual and audio feedback. This restriction limits in particular the immersion of users, i.e. the interest and attention paid during the therapy, as well as more generally the effectiveness of virtual reality therapy. In particular, visual and/or audio feedback can only guide the user to a limited extent, in particular in comparison with the action of the therapist, who can more easily reorient the user and correct errors, for example the development of compensatory movements, replacing the desired solicitation of the muscles.

The Applicant therefore submits that there is currently no satisfactory alternative solution to assist as much as possible in the rehabilitation of a user, so as to correctly carry out physiotherapy exercises and derive all the benefits from them.

Summary of the invention,

The present invention aims to improve the current situation described above.

The present invention aims more particularly to remedy the above limitations by proposing a rehabilitation assistance system capable of stimulating a greater number of sensory perception capacities.

For this purpose, the subject of the present invention relates in a first aspect to a system for assisting in the rehabilitation of at least one part of a user's body, the system comprising:
- at least one haptic device capable of being associated with the user's body;
- at least one motion capture device intended to be associated with the user;
- control electronics; and
- a software application,
the control electronics being configured to control the at least one haptic device, the application being configured to communicate by wired or wireless means with the control electronics and the capture device so as to:
- obtain initial data representative of an ideal user trajectory;
- receive a second data representative of a movement of the user from the at least one capture device;
- compare the movement with the ideal trajectory;
- determining instructions for applying force feedback from the haptic device, based on a result of the comparison;
- transmit instructions to the control electronics.

In other words, the application of the system receives, on the one hand, a trajectory to be performed by the user in connection with the rehabilitation, and on the other hand a movement performed by the user during his rehabilitation. The first data and the second data are, for example, received in the context of performing a specific rehabilitation exercise. According to a particular example, the first data corresponds to a selection of a rehabilitation exercise from a plurality of exercises, each rehabilitation exercise being associated with an ideal trajectory. The ideal trajectory corresponds, for example, to a given movement of a specific joint, or of an upper or lower limb of the user.

The application performs a comparison between the user's movement and the ideal trajectory, i.e. a data matching, or a detection of divergent movements, for example the detection of specific movements corresponding to compensatory movements to be avoided during rehabilitation. The force feedback is thus determined by the application, for its implementation by the haptic device via the control electronics, so as to assist the user and guide him during his rehabilitation, in particular when the user deviates, for example from a given threshold, compared to the ideal trajectory.

In a particular example, the ideal trajectory corresponds to an interval of positions, the comparison of the movement with the ideal trajectory corresponding to determining whether the user's movement falls within the ideal trajectory. When the user attempts to perform a prohibited movement, i.e. when the user's movement departs from the ideal trajectory, the application determines the force feedback to be applied, via the haptic device, to force the user back into the ideal trajectory.

It is understood here that the capture device corresponds to one or more devices, for example a set of sensors, configured to return the second data by communication with the application of the system. The second data corresponds for example to the evolution, over time, of the position of the user or of points representative of the user, for example of his joints. The capture device corresponds for example to any form of sensor known to those skilled in the art and selected according to a variety of criteria, for example the simplicity of use, the precision of capturing the movements of the user or even the interoperability with the other elements of the rehabilitation assistance system.

The control electronics correspond for example to an electronic card associated with the haptic device and in communication with the software application. According to a particular example, the application is implemented at least partially by a microprocessor integrated into the control electronics, the instructions being transmitted by wire. According to another example, the application is implemented remotely on a remote electronic device, for example a central electronic device of the rehabilitation system, the instructions being transmitted by wireless means.

It is further understood that the control electronics may be configured to control a plurality of haptic devices, for example arranged at different points on the user's body, to generate a variety of force feedbacks based on the difference between the ideal trajectory and the user's movement.

The Applicant submits that the human brain has the ability to interpret sensory information provided by haptics, even if it is not real or presented in a natural mode. In particular, blind people can correctly describe textures and shapes presented in virtual reality by receiving haptic stimulation on their skin. This concept is known as sensory substitution, or as a tactile vision substitution system, known as SSVT, and takes advantage of the user's brain plasticity. In particular, sensory substitution makes it possible to provide information to the user that could not have been transmitted by vision or hearing alone; but the visual, sound and tactile flows must be ensured, for example in order to simulate a virtual obstacle.

The Applicant additionally submits that the use of a haptic device portable by the user, in comparison with robotic systems known to those skilled in the art, allows reliable reproduction of tactile sensations in direct contact with the user, in a simple-to-use device with reduced bulk.

By the present invention, the rehabilitation assistance system provides an additional source of sensory data to the user. This sensory data source can be integrated into a control strategy of the rehabilitation system, i.e. a strategy comprising an ideal trajectory associated with a specific movement of the user's body. This control strategy invokes the healthy side of the users' brain to create new movement patterns to control the affected portions of the body, during rehabilitation exercises and then in activities of daily living.

In an advantageous embodiment of the invention, the application is further configured to obtain information representative of a rehabilitation scenario, and obtaining the first data corresponds to a determination of the ideal trajectory based on the rehabilitation scenario.

It is understood here that each rehabilitation scenario is associated with a specific rehabilitation exercise, a type of movement and/or a degree of freedom of an upper or lower limb of the user. Each rehabilitation scenario is for example determined in advance by a specialist, for example an occupational therapist. Obtaining the information representative of a rehabilitation scenario corresponds for example to a reception, by the application, of information representative of the selection of a scenario from a plurality of scenarios recorded in a memory of the rehabilitation assistance system, the memory being in communication with the application. According to another example, obtaining the information representative of the rehabilitation scenario corresponds to a reception of data, for example by manual entry via a human-machine interface, comprising specific characteristics of the rehabilitation scenario.

The person skilled in the art therefore understands that each rehabilitation scenario is associated with an ideal trajectory, i.e. a desired movement encouraged by the rehabilitation scenario. For example, if the rehabilitation scenario is developed to target the flexion-extension movement of the shoulder, the rehabilitation exercise is constructed so as to ensure that the user performs the desired movement to move from an initial position to a final position. The rehabilitation scenario comprises, for example, a plurality of virtual objects to be collected or interacted with, arranged in space according to the ideal trajectory. All other movements, i.e. compensatory movements, correspond to a deviation from the ideal trajectory. The system then generates feedback based on such a deviation.

From the information representative of the rehabilitation scenario, the application then determines the ideal trajectory, i.e. the trajectory that ensures that patients perform the desired movement associated with the rehabilitation scenario. The ideal trajectory then corresponds to a trajectory allowing correct solicitation of the muscles or the absence of compensatory movements.

According to another variant, a plurality of ideal trajectories are recorded in a memory of the rehabilitation assistance system, obtaining the first data corresponding to a selection of the ideal trajectory according to the rehabilitation scenario.

In a particular embodiment, the rehabilitation assistance system further comprises a display device, the application being configured to communicate by wired or wireless means with the display device, such that the display device displays graphic content representative of the first data and/or the second data.

It is understood here that the integration of the display device corresponds to the addition of visual feedback to the rehabilitation assistance system, which is combined with haptic feedback. Such visual feedback is known to those skilled in the art, in particular in the context of virtual reality therapy. The display device corresponds, for example, to a screen placed in front of the user or to a virtual reality headset. The Applicant further submits that the use of a screen or other device remote from the user is preferable to a headset worn directly by the user, so that the user can see his upper and lower limbs during rehabilitation, and control them more precisely.

The graphic content is for example representative of the ideal trajectory and/or the movement of the user and/or a rehabilitation scenario as defined above. According to another example, the application is configured to generate instructions for displaying a visual alert based on a result of the comparison, and transmit these instructions to the display device. Thus, the force feedback is supplemented by a visual alert in order to better guide the user during their rehabilitation.

The Applicant further submits that the integration, in the same system, of the haptic device and a display device, in particular a virtual reality system known to those skilled in the art, allows for centralized determination of the force feedback and the visual feedback, ensuring consistency between the tactile and visual stimuli, for example so as to synchronize the stimuli or more generally to represent an obstacle via several simultaneous and complementary stimuli. This consistency greatly facilitates the recreation, by the user, of new movement models, and therefore increases the effectiveness of the rehabilitation. The skilled person also understands that such advantages are also presented by an integration with a sound device as described below.

Preferably, the application is further configured to:
- generate a virtual scene from the first data;
- determine a position of an avatar representative of the user, in the virtual scene, from the second data,
and in which the graphic content is representative of the virtual scene and the position of said avatar.

It is understood here that the virtual scene corresponds to a visual representation associated with a given rehabilitation exercise, or to the rehabilitation scenario described above, the virtual scene implicitly or explicitly including the ideal trajectory to be respected by the user. The virtual scene and the avatar thus allow the user to better perceive his movement during rehabilitation, with respect to the objectives set for him. The objective associated with the virtual scene corresponds for example to the manipulation of a given virtual object or to reaching a plurality of virtual objects to be collected.

Preferably, the comparison of the motion with the trajectory is performed from the position in the virtual scene.

In other words, the determination of deviations between the user's movement and the ideal trajectory is carried out remotely, by comparing the movement of the user's avatar with the ideal trajectory of the virtual scene. The force feedback applied by the haptic device, or any other additional feedback, is thus determined so as to reinforce the consistency with the graphic content generated by the display device. In a particular design, the force feedback of the haptic device, determined via the application, is added to a determination of visual feedback, or even sound feedback as described below, carried out according to methods known to those skilled in the art. In this example, the application extracts real-time information on the position of the user, represented by an avatar, in the virtual scene, to determine the force feedback.

In an additional embodiment, the rehabilitation assistance system further comprises a sound device, the application being configured to communicate wired or wirelessly with the sound device, such that the sound device generates audio feedback representative of the first data and/or the second data.

It is understood here that, like the display device, the use of sound devices within a rehabilitation assistance system, in particular during virtual reality therapy, is known to those skilled in the art. The rehabilitation assistance system comprises, for example, both a display device and a sound device, or a single device configured to generate graphic content and audio feedback. The audio feedback is, for example, also representative of the virtual scene described above, so as to provide a complete set of sensory information integrating tactile feedback with the already existing visual and audio feedback. A combined design of all the feedback thus makes it possible to maximize the potential for producing and reproducing precise movements.

It is further understood that it is possible to integrate or not the use of visual and/or audio feedback depending on the needs and/or pathology of the user, according to the knowledge of the person skilled in the art.

In a specific embodiment, the at least one haptic device comprises at least one vibration motor.

It is understood here that the vibration motors are configured to generate the force feedback creating sensory information, under the control of the control electronics. Obviously, the at least one haptic device can comprise any electronic component known to those skilled in the art and making it possible to generate pulsations or vibrations on command.

Preferably, the at least one haptic device comprises four vibration motors associated with the body, each vibration motor being associated with a direction.

It is understood here that, for the user's body or a specific body part, for example the body part to be rehabilitated, four vibration motors are associated, each vibration motor being associated with a direction in which the user can move in space. For example, haptic devices are provided associated with a plurality of body parts of the user, each body part then receiving four vibration motors.

The instructions determined by the application are in this same example adapted according to the available directions. The rehabilitation assistance system generates for example, when the user's movement deviates from the ideal trajectory in a given direction, vibrations in this same direction, so as to produce force feedback encouraging or forcing the user to reposition himself in the opposite direction, that is to say on the ideal trajectory.

It is also understood that other designs can be designed in which the haptic device includes a greater or lesser number of vibration motors associated with the same part of the body, the control of the vibration motors being differentiated according to their respective position and the direction with which each vibration motor is associated.

In yet another embodiment, the rehabilitation assistance system includes a plurality of haptic devices corresponding to 14 degrees of freedom of the user's upper and lower limbs.

The person skilled in the art understands here that the 14 degrees of freedom correspond to the 7 degrees of freedom of the upper limbs and the 7 degrees of freedom of the lower limbs. In other words, the haptic devices are associated with the user's body such that each haptic device is associated with a given degree of freedom, all of the degrees of freedom then being covered by the haptic devices. For example, a vibration motor is provided associated with each possible direction of movement of each joint of the upper and lower limbs.

In another embodiment that can be combined with the previous embodiment, the rehabilitation assistance system comprises a plurality of haptic devices configured to be respectively associated with the hands, wrists, arms, legs, feet, ankles, neck and hips of the user.

We understand here that this design makes it possible to associate haptic devices with all of the user's main joints, so as to be able to guide and correct all of their movements.

In an additional embodiment, the haptic device is capable of being associated with the body part.

In other words, the haptic device is specifically designed to be associated with the user's body part for which the system performs rehabilitation. For example, it is expected that the haptic device will be precisely and uniquely associated with the body part being rehabilitated, or that additional haptic devices will be associated, compared to a standard configuration, depending on the body part being rehabilitated.

It is also understood that the above designs can be simplified into a lighter system, depending on the needs and/or pathology, for example by associating haptic devices only with respect to a given joint, degree of freedom or upper or lower limb.

In an additional embodiment, the force feedback corresponds, depending on the result of the comparison, alternately to a blocking or a release of the user's movement.

In other words, the rehabilitation assistance system is configured to reproduce a contact stiffness representing an obstacle towards the user, i.e. a virtual wall preventing the user from deviating from the ideal trajectory. The ideal trajectory thus corresponds to a free trajectory, the other directions of movement generating force feedback.

In other variants, the force feedback is weaker and corresponds, for example, to a simple vibration when the user's movement is incorrect. It is thus possible to design a variety of appropriate feedback intensities to encourage the user to return to the ideal trajectory, for example a simple vibration when the user's movement deviates from the ideal trajectory, or a gradation of the vibration intensity depending on the user's rehabilitation path.

In another embodiment, the force feedback corresponds, depending on the result of the comparison, alternately to a blocking or to a resistance towards the movement of the user.

In other words, when the user's movement matches the ideal trajectory, the rehabilitation assistance system continues to apply force feedback against the user's movement, for example, a weaker force feedback than when the user deviates from the ideal trajectory. Thus, the user must use his muscles more to follow the ideal trajectory, while being guided in this ideal trajectory. This design makes it possible to participate in the user's muscular rehabilitation, in particular in a second phase of rehabilitation once the user has created new movement models. The system then trains the user's muscles to reproduce the instructions given by the brain.

It is still possible to imagine other variants, for example a force feedback configured to accompany the user's movement in the ideal trajectory, by assisting the correct movements in addition to blocking deviations. The person skilled in the art understands here that the level of assistance or resistance depends mainly on the user's profile and rehabilitation path.

In an additional embodiment, the application is further configured to receive a third piece of data representative of a level of rehabilitation of the user, and the instructions for applying the force feedback are further determined based on the third piece of data.

In other words, this design makes it possible to adapt, as suggested in the variants described above, the force feedback according to information specific to the user, in particular their needs and physical abilities. The third data is for example merged with the first data, or included in information representative of a rehabilitation scenario as described above. The application receives for example information making it possible to characterize both the type of movement to be performed by the user, therefore the ideal trajectory, and the level of force to be applied when the user performs this movement, whether in order to accompany, resist, or block the user's movement.

In a specific embodiment, the second data comprises a set of information representative of distance between the capture device and the user, the application being configured to determine the movement of the user from the set of information representative of distance.

In other words, the user's movement results from the evolution of the distance between the user and the capture device, in particular specific points of the user. The capture device is for example configured to measure the distance between the capture device and the user's joints, the evolution of the distances associated with each joint being transcribed into a movement of the user.

It is also understood that the information included in the second data varies depending on the selected capture device, and that it is possible to design multiple variants of the rehabilitation assistance system, using a plurality of capture devices known to those skilled in the art and appropriately processing the data from the capture devices.

According to a second aspect, the present invention relates to a computer program comprising instructions for implementing the following steps:
- obtaining initial data representative of an ideal trajectory of a user;
- receiving a second data representative of a user movement from at least one capture device;
- comparison of the movement with the ideal trajectory;
- determination of instructions for applying force feedback from a haptic device, based on a result of the comparison;
- transmission of instructions to a control electronics of the haptic device.

It is understood here that the computer program comprises instructions adapted for the execution of the steps implemented by the software application according to the first aspect of the present invention.

According to a variant, the computer program also comprises instructions adapted for the execution of the variants described above in connection with the first aspect of the present invention.

According to a third aspect, the present invention relates to a computer-readable recording medium on which a computer program according to the second aspect of the invention is recorded.

On the one hand, the recording medium may be any entity or device capable of storing the program. For example, the medium may include a storage medium, such as a ROM memory, a CD-ROM or a microelectronic circuit type ROM memory, or a magnetic recording medium or a hard disk.

On the other hand, this recording medium may also be a transmissible medium such as an electrical or optical signal, such a signal being able to be conveyed via an electrical or optical cable, by conventional or hertzian radio or by self-directed laser beam or by other means. The computer program according to the present invention may in particular be downloaded from a network such as the Internet.

Alternatively, the recording medium may be an integrated circuit in which the computer program is incorporated, the integrated circuit being adapted to perform or to be used in performing the method in question.

Thus, through the various functional and structural technical characteristics above, the Applicant proposes a rehabilitation assistance system and program allowing haptic sensory feedback, offering a greater amount of information to the user and which can be combined with the visual and sound feedback known in virtual reality therapy.

Brief description of the figures

Other characteristics and advantages of the present invention will emerge from the description of the particular and non-limiting exemplary embodiments of the present invention below, with reference to the appended figures 1 and 2 and in which:

There schematically illustrates a system for assisting in the rehabilitation of at least one part of a user's body, according to a particular and non-limiting exemplary embodiment of the present invention;

There illustrates a flowchart of the different stages of a rehabilitation assistance process implemented by a system conforming to the .

Detailed description

A system for assisting in the rehabilitation of at least one part of a user's body will now be described in the following with joint reference to figures 1 and 2 annexed to the description. The same elements are identified with the same reference signs throughout the description which follows.

As stated in the preamble to the description, current virtual reality therapy solutions are limited to visual and/or audio feedback, which provide limited engagement with the user and do not allow for precise guidance of their movements during rehabilitation exercises.

One of the objectives of the present invention is to enable the use, by a person in rehabilitation, for example in a situation of handicap, of a system maximizing the recovery of physical skills and sensory stimulation.

This is made possible in the example described below.

According to the example of the , a rehabilitation assistance system 100 is used by a user 3, for example a person who has suffered a stroke or is suffering from any disability, for whom rehabilitation is likely to increase motor skills.

In this same example, the system 100 comprises at least one haptic device 110 capable of being associated with the body of the user 3, that is to say worn, for example in direct contact with the body, during its use.

Such a haptic device 110 comprises for example at least one vibration motor, that is to say a device configured to generate vibrations of fixed or variable intensity according to a command. More generally, the haptic device 110 comprises one or more electronic components known to those skilled in the art and configured to generate vibrations or pulsations in a controlled manner. It is understood here that, depending on the variants envisaged, the needs and objectives of those skilled in the art, a plurality of haptic devices 110 can be used, for example according to the tactile sensation or the desired force feedback. The haptic device 110 can in particular be selected, in accordance with the description below, according to its ability to imitate a wall or a virtual barrier, that is to say to block the movement of the user 3 when activating the haptic device 110.

According to a particular variant, the system 100 comprises a plurality of haptic devices 110 associated with the same user 3, for example worn on different parts of the body of the user 3. The plurality of haptic devices 110 is for example associated with the 14 degrees of freedom of the upper and lower limbs of the user 3 or with all of the main joints of the user 3, i.e. the hands, wrists, arms, legs, feet, ankles, neck and hips. Of course, it is also possible to provide haptic devices 110 associated only with a subset of the 14 degrees of freedom or the main joints stated above. According to yet another design, the haptic devices 110 are associated specifically, or in combination with the variants described above, with the part of the user's body for which the system 100 performs rehabilitation.

The system 100 also comprises at least one motion capture device 120, which is also intended to be associated with the user 3. It is understood here that the motion capture device 120 is configured to track the movement of the user 3 over time, and can be implemented by a variety of means known to those skilled in the art. In a preferred embodiment, the capture device 120 comprises at least one Azure Kinect® sensor, i.e. an apparatus comprising a depth sensor, a spatial microphone array with a video camera and an orientation sensor, and allowing precise tracking of the movements of the user 3. In another embodiment, the system 100 comprises or is coupled to a virtual reality therapy system 150, as described below, comprising a virtual reality headset. The capture device 120 comprises, in this example, a plurality of sensors linked to the virtual reality headset. Such sensors are known to those skilled in the art, for controlling an avatar of the user 3 in a virtual scene, for example the virtual scene generated by the application as described below or more generally any virtual scene produced in the field of virtual reality. Of course, the capture device 120 can advantageously comprise a combination of the above sensors.

In combination with the haptic device 110 and the capture device 120, the system 100 comprises control electronics 130 in communication with the haptic device 110, so as to control it. The control electronics 130 are for example integrated into the haptic device 110 or configured to be connected to a plurality of haptic devices 110 worn by the user 3. In order to allow the control of the electronic elements of the system 100, in particular the haptic devices 110, the control electronics 130 comprise for example a power supply and at least one processor. In a preferred embodiment, the control electronics 130 comprise an electronic card, for example of the Arduino® type, programmed for controlling the haptic device 110.

Finally, the system 100 also comprises a software application configured to communicate with the capture device 120 and the control electronics 130 by wired or wireless means. According to a first design, the software application is directly implemented by the processor of the control electronics 130, the latter communicating with the other elements of the control electronics 130 by wired means. According to a second design, the software application is implemented by a remote device 140 in communication with the control electronics 130, in particular with the processor of the control electronics 130. This design makes it possible in particular to limit the processing capacities required by the control electronics 130 in favor of means of communication with the remote device 140. The remote device 140 corresponds for example to an electronic device associated with a therapist, for example equipped with a human-machine interface 160 with which the therapist can interact to guide the rehabilitation of the user 3. According to yet another variant, the remote device 140 is integrated into a virtual reality therapy system 150, as described below and known to those skilled in the art. The software application and the control electronics 130 thus make it possible to receive data from the capture device 120 and to control the haptic device 110.

Optionally, the system 100 also comprises a display device 151 and/or a sound device 152, the software application being configured to also communicate with the display device 151 and/or the sound device 152 for rendering visual and/or audio feedback. The display device 151 and the sound device 152 are for example grouped in a virtual reality therapy system 150 known from the prior art and allowing visual and audio feedback. According to a first design, the software application is in communication with the virtual reality therapy system 150, the assembly formed by the haptic device 110, the capture device 120 and the control electronics 130 being separate from the virtual therapy system 150. According to another design in accordance with the , the virtual reality therapy system 150 and the other elements described above are grouped within the system 100 and controlled jointly, the software application being implemented by the virtual reality therapy system 150 or by the remote device 140. In particular, a combined control of the haptic device 110 and the virtual reality therapy system 150 makes it possible to ensure consistency between the force feedback and the visual and/or audio feedback, by integrating the haptic device 110 and the virtual reality therapy system 150 into the same system 100.

It is understood here that the visual feedback from the display device 151 corresponds to a graphic content, for example a graphic content representative of the data processed below during the method of the . The visual feedback, audio feedback and force feedback of the haptic device 110 advantageously correspond to complementary renderings of the same data making it possible to stimulate all of the senses of the user 3 during his rehabilitation. The complementarity between the different renderings, or more generally the joint control of the feedback within the system 100, also allows the brain of the user 3 to interpret more precisely the sensory information transmitted and to develop new movement models during his rehabilitation with greater ease.

The system 100 described above is thus configured to implement the steps of a rehabilitation assistance method according to the . Such a method is for example recorded according to instructions in a computer program, for example recorded in a dedicated recording medium, for example in a memory of the control electronics 130, of the remote device 140 or of the virtual reality therapy system 150.

In a first step 21, the application obtains a first piece of data representative of an ideal trajectory of the user 3. In other words, the first piece of data depends on the rehabilitation that one seeks to carry out and represents a movement objective for the user 3. The first piece of data is thus, for example, received by communication with the virtual reality therapy system 150, that is to say that the application receives information on the rehabilitation exercise carried out via the virtual reality therapy system, in order to integrate the control of the haptic device 110 therein. According to another example, the first piece of data is received by communication with the human-machine interface 160 and corresponds to an instruction given by the therapist.

According to a variant, the application is configured to obtain information representative of a rehabilitation scenario. Obtaining the first data then corresponds to a determination of the ideal trajectory according to the rehabilitation scenario. It is understood here that a rehabilitation scenario corresponds to a given rehabilitation exercise, corresponding to a specific type of movement, to a joint or even to a given degree of freedom of the user 3. In other words, the software application determines, according to the rehabilitation exercise to be performed or parameters associated with such an exercise, the ideal trajectory that the user 3 must maintain. The ideal trajectory therefore corresponds to the trajectory which ensures that the user 3 absolutely performs the desired movement, for a given rehabilitation scenario.

The determination of the ideal trajectory corresponds, for example, to a selection of the ideal trajectory from a set of predefined trajectories, for example based on manual selection information from the therapist, or based on a selected rehabilitation scenario, the correspondence between the ideal trajectory and the rehabilitation scenario being recorded in a memory in communication with the software application.

In a second step 22, the application receives from the capture device 120 a second piece of data representative of a movement of the user 3. In accordance with the description above, the second piece of data is thus transmitted by the capture device 120 to the control electronics 130, the remote device 140 or even the virtual reality therapy system 150, depending on the component implementing the software application.

In a preferred embodiment, the second data item comprises a set of information representative of the distance between the capture device 120 and the user 3. The set of information corresponds for example to the distances between the capture device 120 and the joints of the user 3, as perceived by the capture device 120. The application then determines the movement of the user 3 from the set of information representative of the distance, for example according to their evolution over time or by positioning the user 3 with respect to the reference position of the capture device 120. Obviously, the information included in the second data item, and their possible processing to obtain the movement of the user 3, depend on the type of capture device 120 used in the system 100.

In a third step 23, the movement of the user 3 is compared with the ideal trajectory, that is to say that the application matches the movement with the ideal trajectory or identifies and characterizes any possible deviation of the movement from the ideal trajectory.

According to a particular embodiment variant, in which the rehabilitation assistance system 100 comprises the display device 151, the application is configured to generate a virtual scene from the first data. The application then determines a position of an avatar representative of the user 3 in the virtual scene from the second data. The graphic content rendered by the display device 151 is then representative of the virtual scene and the position of the avatar. Optionally, the system 100 also comprises the sound device 152, the audio feedback also being representative of the virtual scene.

In this same variant, the comparison between the movement and the ideal trajectory is carried out from the position of the avatar of user 3 in the virtual scene. In other words, the position of the avatar in the virtual scene makes it possible to determine whether or not the movement of user 3, for example the position of a given limb, is located in the ideal trajectory.

In a fourth step 24, the application determines instructions for applying force feedback from the haptic devices 110 based on a result of the comparison. The instructions are then transmitted in a fifth step 25 to the control electronics 130, which implements them by controlling the haptic devices 110. Controlling the haptic devices 110 corresponds, for example, to starting or stopping the vibration motors.

Thus, when the movement of the user 3 corresponds to the ideal trajectory, it is understood that the haptic devices 110 do not provide any force feedback. Similarly, any visual and audio feedback is adapted so as not to alert the user 3; for example, a simple audio feedback representing the evolution of the movement of the user 3 is provided.

On the contrary, when the movement of the user 3 deviates from the ideal trajectory, the control of the haptic devices 110 is adapted to indicate this deviation to the user 3 and force him to return to the ideal trajectory. The visual and audio feedback also includes for example an alert or an indication of the correction to be made to return to the ideal trajectory.

It is understood here that the instructions, or their implementation via the control electronics 130, are adapted according to the number and/or the position of the haptic devices 110. The control electronics 130 triggers for example the vibration of precise haptic devices 110 in order to indicate more precisely to the user 3 which joint to reposition or in which direction to correct the movement.

For example, in a specific variant, the haptic device 110 comprises four vibration motors associated with the body of the user 3, the vibration motors being arranged such that each vibration motor is associated with a respective direction. In other words, each vibration motor generates, upon activation, force feedback in the direction with which it is associated. This design thus makes it possible to guide the user 3 so as to force him to move in the opposite direction. The instructions and/or their implementation by the control electronics 130 are then adapted to precisely activate one or more vibration motors included in a given haptic device 110, making it possible to redirect the articulation of the user 3 in a specific direction, rather than simply indicating an error in the movement. It is understood that this design can be adapted according to the number and arrangement of the vibration motors.

In parallel, the instructions or their implementation can also be adapted in intensity, according to the type or the operating interval of the haptic devices 110, so as to provide adaptive force feedback depending on the user 3 or on the amplitude of the difference between the movement and the ideal trajectory. According to a specific design, the force feedback corresponds to a blocking or a release of the movement of the user 3. The haptic devices 110 are thus controlled to prevent the user 3 from deviating further from the ideal trajectory, or more generally to provide significant resistance, depending on the capacity of the haptic devices 100 to imitate a virtual wall. Of course, such blocking of the movement is associated with a specific direction, the return of the user 3 in the ideal trajectory remaining released.

According to another variant, the force feedback corresponds alternately to a blockage or resistance to the movement of the user 3. In other words, when the user 3 follows the ideal trajectory, the haptic device 110 continues to apply force feedback, for example a weaker force feedback than when the user 3 deviates from the ideal trajectory. The user 3 must therefore provide additional effort to perform the desired movement, which contributes to muscle rehabilitation.

It is therefore understood that the force feedback can be adapted in a variety of ways, in particular according to the user's rehabilitation path. In yet another design, the application also receives a third piece of data representative of a level of rehabilitation of the user 3, or more generally representative of a profile of the user 3. The determination of the instructions according to the fourth step 24 is then further carried out according to the third piece of data, i.e. in order to adapt the force feedback according to the user 3. The application obtains for example jointly the first piece of data and the third piece of data in a rehabilitation scenario determined for a movement and a specific rehabilitation path, i.e. a scenario for which the ideal trajectory and the force feedback are predetermined.

According to a specific example, this third data item comprises information representative of a muscle rehabilitation force, the force feedback being determined according to this muscle rehabilitation force. This adaptation of the force feedback applies for example when the user 3 follows the ideal trajectory, in order to apply a resistance as described above or conversely in order to guide the user 3 by accompanying his movement with a force in the same direction. The adaptation of the force feedback can also apply when the user 3 deviates from the ideal trajectory, in order to be more or less permissive towards deviations and compensation movements, and to balance the engagement of the user 3 with the correction of his errors.

Thus, it will be understood that the present invention provides a rehabilitation assistance system allowing, in a simple manner, to improve the precision of the users' movements during rehabilitation by providing haptic feedback simulating a tactile sensation, the haptic feedback guiding the user and correcting his movements. Such a system can advantageously be combined with already known virtual reality therapy systems in order to realize a variety of learning scenarios created by therapists and to ensure consistency between all the feedback so that the haptic feedback facilitates the user's learning of the movements.

It should be noted that this detailed description relates to a particular embodiment of the present invention, but that in no case does this description have any limiting character with respect to the subject matter of the invention; on the contrary, its objective is to remove any possible imprecision or misinterpretation of the claims which follow.

It should also be noted that the reference signs placed in parentheses in the following claims are in no way limiting; these signs have the sole purpose of improving the intelligibility and understanding of the following claims as well as the scope of the protection sought.

Claims (15)

System (100) for assisting in the rehabilitation of at least one part of the body of a user (3), said system comprising:
- at least one haptic device (110) capable of being associated with the body of said user (3);
- at least one motion capture device (120) intended to be associated with said user (3);
- control electronics (130); and
- a software application,
said control electronics (130) being configured to control said at least one haptic device (110), said application being configured to communicate by wired or wireless means with said control electronics (130) and said capture device (120) so as to:
- obtain (21) a first data representative of an ideal trajectory of said user (3);
- receiving (22) a second data representative of a movement of said user (3) from said at least one capture device (120);
- compare (23) said movement with said ideal trajectory;
- determining (24) instructions for applying force feedback to said haptic device (110), based on a result of said comparison;
- transmit (25) said instructions to said control electronics (130). Rehabilitation assistance system (100) according to claim 1, in which said application is further configured to obtain information representative of a rehabilitation scenario, and in which said obtaining (21) of said first data corresponds to a determination of said ideal trajectory as a function of said rehabilitation scenario. A rehabilitation assistance system (100) according to claim 1 or 2, which further comprises a display device (151), said application being configured to communicate by wired or wireless means with said display device (151), such that said display device (151) displays graphical content representative of said first data and/or said second data. The rehabilitation assistance system (100) of claim 3, wherein said application is further configured to:
- generate a virtual scene from said first data;
- determining a position of an avatar representative of said user (3), in said virtual scene, from said second data,
and wherein said graphic content is representative of said virtual scene and said position of said avatar. A rehabilitation assistance system (100) according to claim 4, wherein said comparison (23) of said movement with said trajectory is performed from said position in said virtual scene. Rehabilitation assistance system (100) according to one of claims 1 to 5, which further comprises a sound device (152), said application being configured to communicate by wired or wireless means with said sound device (152), such that said sound device (152) generates audio feedback representative of said first data and/or said second data. Rehabilitation assistance system (100) according to one of claims 1 to 6, wherein said at least one haptic device (110) comprises at least one vibration motor. The rehabilitation assistance system (100) of claim 7, wherein said at least one haptic device (110) comprises four vibration motors associated with said body, each vibration motor being associated with a direction. Rehabilitation assistance system (100) according to one of claims 1 to 8, which comprises a plurality of haptic devices (110) corresponding to 14 degrees of freedom of the upper and lower limbs of said user (3). Rehabilitation assistance system (100) according to one of claims 1 to 9, which comprises a plurality of haptic devices (110) configured to be respectively associated with the hands, wrists, arms, legs, feet, ankles, neck and hips of said user (3). Rehabilitation assistance system (100) according to one of claims 1 to 10, wherein said haptic device (110) is capable of being associated with said body part. Rehabilitation assistance system (100) according to one of claims 1 to 11, in which said force feedback corresponds, depending on said result of said comparison, alternately to a blocking or a release of said movement of said user (3). Rehabilitation assistance system (100) according to one of claims 1 to 12, in which said second data comprises a set of information representative of distance between said capture device (120) and said user (3), said application being configured to determine said movement of said user (3) from said set of information representative of distance. Computer program product comprising instructions for implementing the following steps:
- obtaining (21) a first data representative of an ideal trajectory of a user (3);
- reception (22) of a second data representative of a movement of said user (3) from at least one capture device (120);
- comparison (23) of said movement with said ideal trajectory;
- determining (24) instructions for applying force feedback from a haptic device (110), based on a result of said comparison;
- transmission (25) of said instructions to control electronics (130) of said haptic device (110),
when these instructions are executed by a processor. Computer-readable recording medium on which a computer program according to claim 14 is recorded.