Apparatus for generating sensations of movement and for physical rehabilitation
View Patent ↗The appliance designed to allow a living being to perceive sensations of virtual movements of part of his body comprises a control unit in which is stored a table containing a first plurality of basic excitation signals, a second plurality of macro-motifs each formed by a third plurality proper of the basic signals, a sequencer reading the macro-motifs in order to emit a second plurality of corresponding commands for excitation, each time, of a third plurality proper of vibrators selected from among a first plurality of vibrators carried by a coupling support in predetermined respective zones of the part of the body, the excitation of the third plurality proper of vibrators by the second plurality of commands being intended to mechanically stimulate elements of the body, to provoke the creation of bioelectrical signals in the living being, allowing him to perceive sensations of a given virtual movement.
1. A method for generating a macro-pattern having a plurality of elementary excitation signals that induces bioelectric signals in a human body causing a human being to perceive sensations of a virtual movement of a body part when the plurality of elementary excitation signals are supplied to a plurality of vibrators disposed at predetermined positions arranged along subparts of the body part, the method comprising the steps of:
a) determining in advance the macro-pattern corresponding to the virtual movement of the body part of the human being;
b) applying vibrations corresponding to the plurality of elementary excitation signals of the macro-pattern to the predetermined positions arranged along the subparts of the body part of the human being;
c) collecting sensation indications from the human being that are indicative of the virtual movement perceived by the human being in response to step b);
d) iterating steps b) and c) while varying parameters of the macro-pattern in response to the sensation indications collected in accordance with step c) until the collected sensation indications correspond to a satisfactory sensation perception of the virtual movement.
2. The method according to claim 1 , wherein the subparts of the body part that receive the plurality of vibrators are tendons belonging to muscles that are involved when the body part executes a real movement corresponding to the virtual movement, the tendons being mechanically stimulated by the plurality of vibrators supplied with the plurality of elementary excitation signals of the macro-pattern.
3. The method according to claim 2 , wherein the parameters that are varied in accordance with step d) comprise at least one of the following:
a frequency change to the plurality of elementary excitation signals;
an amplitude change to the plurality of elementary excitation signals; and
an amplitude and frequency change to the plurality of elementary excitation signals.
4. The method according to claim 1 , wherein the macro-pattern is determined in step a) as a result of the plurality of elementary excitation signals each being picked up in a nerve close to sensory fibers originating from physiological receptors of the body part of the human being executing a real movement of the body part corresponding to the virtual movement.
5. A method for generating a macro-pattern having a plurality of elementary excitation signals that induces bioelectric signals in a body of a living being causing the living being to perceive sensations of a virtual movement of a body part when the plurality of elementary excitation signals are supplied to a plurality of vibrators disposed at predetermined positions arranged along subparts of the body part, the method comprising the steps of:
a) determining instantaneous velocity vectors following a given path of points spaced in time that corresponds to the virtual movement;
b) identifying muscles of the living being that would be involved if the living being performed with the body part an actual movement corresponding to the virtual movement;
c) identifying for the muscles identified in accordance with step b) directions of maximum sensitivity for sending bioelectric signals to a brain of the living being in response to actual movements of the body part; and
d) establishing the macro-pattern by characterizing the plurality of elementary excitation signals from an analysis of the instantaneous velocity vectors relative to the directions of maximum sensitivity of the muscles.
6. The method of claim 5 , wherein the given path is recorded and smoothed by using a low-pass filter and wherein the determination of the velocity vectors is performed for equally spaced points in time.
7. The method according to claim 5 , further comprising the steps of:
e) setting a respective frequency of the plurality of elementary excitation signals to a maximum excitation frequency for each vibrator of the plurality of vibrators when the instantaneous velocity vectors are oriented along the direction of maximum sensitivity of each respective muscle of the muscles identified in accordance with step b), and
f) setting a respective frequency of the plurality of elementary excitation signals to an excitation frequency that becomes smaller and smaller as an orientation of the instantaneous velocity vectors moves away from the direction of maximum sensitivity of the respective muscle under consideration until a minimum value of excitation of the plurality of vibrators is reached.
8. The method according to claim 7 , wherein the maximum excitation frequency is set to 100 Hz.
9. The method according to claim 7 , wherein the respective frequency of the plurality of elementary excitation signals with respect to the maximum excitation frequency is determined as a function of the cosine of an angle between the instantaneous velocity vectors and the direction of maximum sensitivity of the respective muscle under consideration.
10. The method according to claim 5 , wherein the plurality of elementary excitation signals have an amplitude that is set at a predetermined value.
11. The method according to claim 10 , wherein the macro-patterns is generated by characterizing a frequency of the plurality of elementary excitation signals from analysis of the instantaneous velocity vectors relative to the directions of maximum sensitivity of the muscles.
12. The method according to claim 5 , wherein the instantaneous velocity vectors are determined and the directions of maximum sensitivity of the muscles are represented in a common reference system.
13. The method according to claim 12 , wherein the common reference system is an orthogonal coordinate system.
14. The method according to claim 12 , wherein the virtual movement corresponds to an actual movement of the body part of the living being, the performance of which involves a single joint of the body.
15. The method according to claim 14 , wherein the common reference system is centered on the single joint and is a system of orthonormal axes.
16. The method according to claim 14 , wherein the common reference system is centered on a segment end of the body part that moves along the given path.
17. The method according to claim 5 , wherein the given path is two-dimensional.
18. The method according to claim 5 , wherein the given path is three-dimensional.
19. A method for generating a macro-pattern having a plurality of elementary excitation signals that induces bioelectric signals in a body of a living being causing the living being to perceive sensations of a virtual movement of a body part when the plurality of elementary excitation signals are supplied to at least one vibrator disposed at a predetermined position arranged along subparts of the body part, the method comprising the steps of:
a) determining instantaneous velocity vectors following a given path of points spaced in time that correspond to the virtual movement;
b) identifying muscles of the living being that would be involved if the living being performed with the body part an actual movement corresponding to the virtual movement;
c) identifying for the muscles identified in accordance with step b) directions of maximum sensitivity for sending bioelectric signals to a brain of the living being in response to actual movements of the body part; and
d) establishing the macro-pattern by characterizing the plurality of elementary excitation signals from an analysis of the instantaneous velocity vectors relative to the directions of maximum sensitivity of the muscles;
e) setting a respective frequency of the plurality of elementary excitation signals to a maximum excitation frequency for vibrations applied to the body part by the at least one vibrator when the instantaneous velocity vectors are oriented along the direction of maximum sensitivity of each respective muscle of the muscles identified in accordance with step b); and
f) setting a respective frequency of the plurality of elementary excitation signals to an excitation frequency that becomes smaller and smaller as an orientation of the instantaneous velocity vectors moves away from the direction of maximum sensitivity of the respective muscle under consideration until a minimum value of excitation of the vibrations is reached.