ITRM20120031A1 - ARTICULATED ACTIVE SEAT SYSTEM WITH ELECTRONIC CONTROL. - Google Patents

Description

"ARTICULATED ACTIVE SEAT SYSTEM WITH ELECTRONIC CONTROL"

DESCRIPTION

The present invention relates to an articulated active sitting system as an aid for subjects with congenital or acquired lesions of the Central Nervous System (CNS). Deepening the knowledge of adaptive capacities to the living environment is a complex and specific task as much as elaborating intervention strategies to seek change from fixed and stable conditions imposed by the disease. The interplay of forces in a multi-articulated organism, the relationship between internal and external forces and the laws that govern the dynamics determine physical changes of state which in terms of recovery of function mean readjustment to the environment in which one lives. Movement, therefore, understood as the set of essential phases for controlling the position of the body in space, can be considered as the ability of the central nervous system (CNS) to regulate and make the most of the available stiffness and can represent the The only possible dialogue with the environment.

This is the case of subjects with congenital or acquired CNS lesions who present in more or less serious forms of posture control problems that must be addressed with devices that the market does not currently offer.

A relevant clinical-rehabilitative problem consists of flexion-torsion and extension dystonias in which prolonged involuntary muscle contractions and violent spasms characterized by the simultaneous activation of agonist and antagonist muscles involve the entire body axis, with retro and antecollar stiff neck, severe scoliosis of the trunk, pelvic tilt, hip flexion, extension and sub-dislocation or uni or bilateral dislocation, with associated axial deviation to the right or left, with bilateral flexion or extension of the knees, plantiflexion or dorsiflexion of the ankles , feet in pronation or supination with claw toes, while the upper limbs are placed in adduction and internal rotation of the shoulders, flexion at the elbows and wrists, hands variously deformed in closing or opening in athetoid postures. These postures, although sustained for a long time, are fluctuating, capricious and rebellious to any form of forced containment; both the wheelchair and the posture systems normally on the market are inadequate not only for the prevention or containment of deformities, but also for the simple containment of the subject who, inevitably, slips into the wheelchair, ending up with the head reclined in torsion and hyperextension outside the backrest, irrepressible by the various types of headrests or lateral supports, while the only block completely sliding out of the wheelchair is constituted by the support to separate the legs, against which the inguinal region of the patient is strongly compressed with the possibility of injuries.

Sometimes the collision with the back of the wheelchair can occur in an unpredictable and violent way to the point of causing damage to the shoulder blades or to the joints of the track; There are reports of very young children, three months old, who manage to dislodge the maternal shoulder trying to contain the sudden spasm during breastfeeding.

The essential characteristic of the forces at play appears to be the unpredictable violence and the instantaneousness with which the dystonic movements take place. However, it is a qualitative assessment based on observation alone, which is independent of any type of kinematic, dynamic and energetic quantification of the dystonic event.

State of the art and disadvantages of the prior art

At present there are no devices that are able to accompany the subjects affected by these pathologies in all the movements originated by dystonia and even less able to withstand the stresses imposed by the powers involved without damaging themselves or, even worse, causing injury to the patient.

Some devices developed quite recently propose to follow only some of the preferential trajectories of the dystonic event with a limited excursion and to passively dampen the energy released by the dystonias of the large extensor muscles. In all devices, the symmetrical flexion-extension of the trunk with respect to the lower limbs around the hip joint is mainly taken into consideration.

In particular, one of these solutions is made by means of a backrest and a seat made of internally padded thermoplastic material, connected to each other with a rear leaf spring made of carbon fiber which allows a very limited range of flexion and extension from mechanical limit switches (about 10 °). The flexion-extension movements of the knee and ankle joints are not taken into consideration (the legs and feet are not contained in any way), the arching in the sagittal plane and the torsion of the trunk that in subjects suffering from severe dystonia It is of fundamental importance in determining the dystonic trajectories and lesions of the musculoskeletal system.

Other devices on the market, while applying different devices, substantially retain the characteristics of the one just examined.

Another solution currently on the market consists of a backrest, a seat and a platform for the accommodation of the feet articulated together with several flat hinges positioned at the level of the anatomical hip and knee joints of the patient. This system exploits the action of the force of gravity, springs and hydraulic dampers for the containment and recovery of posture. As it is designed, it deforms only in the sagittal plane allowing a limited range of flexion-extension of the hip and knee without taking into consideration neither the flexion and extension of the ankle nor the torsional components of the trunk whose importance it has already been said.

The systems currently available are not sufficient precisely because of the complexity of the trajectories that originate from the innumerable degrees of freedom of the totality of the joints involved and the dynamic components that arise from the random and uncontrollable activation of the entire muscular system involved. in the dystonic phenomenon. The simplification adopted in the construction of the devices on the market means that most of the trajectories are neglected and blocked and this inevitably leads to the impact between the user's body and the containment device.

About a decade ago, in order to take into account both the flexion and extension movements in the sagittal plane and the torsion movements in the transverse plane of the trunk, a fully mechanical adaptive torsion and flexion dynamic backrest was studied, designed, manufactured and tested. .

The structure was intended to replicate the kinematic conformation of the spine and provided for a series of mechanical modules stacked to form a central column, similar to vertebrae that allow torsion in the transverse plane and flexion in the sagittal plane. The interposition of variable stiffness compression springs was intended to allow the patient to return to the starting position. Clinical tests carried out on patients have shown, especially in subjects suffering from severe dystonia, system limitations:

â € ¢ the presence of restraints in the backrest prevented some movements of the patient; from the observation, purely of a qualitative type, having neglected the flexion of the trunk in the frontal plane, the flexion-extension of the hip, knee and ankle made the system insufficient to follow the majority of the trajectories imposed by the dystonic movement on the muscular apparatus. skeletal.

â € ¢ the calibration of the springs, necessary to adapt the dynamic response of the system, was very complex as the behaviors of the individual patients were highly differentiated in the postures, in the energy developed, in the acceleration and in the frequency of repetitive movements; the same patient expresses the dystonic event in a different way over time, orienting himself in space according to different kinematic and kinetic characteristics. It is therefore evident the need to collect and analyze data relating to the kinematics and kinetics of the dystonic event to acquire new knowledge, currently unavailable, necessary to tackle the problem of containing subjects affected by severe dystonia.

â € ¢ During the dystonic event, the potential energy was accumulated by the springs in the form of elastic potential energy, thanks to the work done by the muscular force, following a displacement equal to the length of the path imposed by the dystonia itself. Once the dystonic event ended, the accumulated potential energy was returned in the form of kinetic and potential energy thanks to the work done by the decompression springs. This energy, due to the â € œmonocolumnâ € structural conformation, was returned along a return trajectory which was the shortest between the starting point and the arrival point and which was completely different from the forward one. In this way the return movement took place with greater acceleration and speed and without any type of damping except that linked to the hysteresis of the springs and to the internal friction of the mechanical system. This meant that the system did not approach, stopping, the starting point but that it oscillated around that position.

â € ¢ in the case of subjects with severe dystonia, when the dystonic movement, especially of the extensor-torsional type, brought the patient's center of gravity below the instantaneous rotation center of the mechanical system, the action of the springs , however, calibrated to gradually deform and allow the patient to move in flexion-torsion, was unable to bring him back to the starting position because, due to the `` single column '' structure, a stable equilibrium configuration was reached in a position completely different from the starting one and therefore posturally incorrect.

â € ¢ the aspect of the system, strongly characterized as a mechanical apparatus, was psychologically disturbing and had to be mitigated in order to cure, beyond the functional aspect alone, the socialization relationship between the patient and others, whether they are children , adults, relatives or strangers.

It is therefore necessary to activate the system by introducing an electronic control in order to adequately dampen the system and to appropriately establish the return trajectory to the starting position.

Aims of the Invention

The fundamental need for subjects suffering from dystonia consists in having a containment structure available that can accompany the patient in his dystonic shots in retropulsive extension and torsion, without making him lose contact with the seating system, but with increasing resistance such as to develop a controlled yielding with subsequent restitution and gradual recovery of the initial position or of an acceptable optimal equilibrium position with respect to the limits imposed by the pathology in question. Such a device could also constitute a variable environment potentially training towards the modification and therefore instructive in determining return trajectories for the single patient.

The object of the present invention is to solve the numerous problems still left open by the known art and this is achieved through an articulated active seating system as defined in claim 1.

Further characteristics of the present invention are defined in the corresponding dependent claims.

Advantages of the Invention

The present invention, overcoming the aforementioned problems of the known art, entails numerous and evident advantages.

In particular, the present invention allows to obtain an optimal containment of postures and involuntary movements, while preventing the force released violently in the dystonic movement of flexion, torsion and extension of the trunk and head and of the distal segments from being totally discharged on the spine. vertebral and on the main joints of the musculoskeletal system, containing the evolution of very serious rotoscoliosis and irreversible damage to the joint complexes (dislocations, ruptures of the ligaments and synovial capsules, etc.) otherwise facilitated by the current ordinary posture systems.

This therefore allows to prevent secondary damage to the body areas of hyperpressure from impact (pubic area, genitals, etc.) and favors the learning processes of a â € œcomplianceâ € with the device such as to allow the patient to experiment with more balanced trajectories. change when you return to basic â € œpreferentialâ € postures.

Furthermore, the system according to the present invention allows to continuously monitor, thanks to a suitable software, the characteristics of the patient's dystonic events allowing to objectively evaluate the improvement or worsening of the pathology over time. In this way, the system can also be used as a tool to verify the effectiveness of a pharmacological, rehabilitative or combined treatment aimed at reducing the dystonic problems of patients with brain damage.

Brief description of the drawings

The present invention, overcoming the problems of the known art, entails other numerous and evident advantages which, together with the characteristics and methods of use of the present invention, will become evident from the following detailed description of its preferred embodiments, presented by way of non-limiting example. , referring to the figures of the attached drawings, in which:

- Figures 1A, 1B, 1C are exemplary diagrams of a part of the overall kinematic operation of a system according to the present invention, representing, in particular, the section according to a lateral / sagittal plane; figures 2A, 2B, 2C are exemplary diagrams of an ankle joint of the system according to the present invention;

- Figures 3A, 3B, 3C are exemplary diagrams of a knee joint of the system according to the present invention;

- figures 4A, 4B, 4C are exemplary diagrams of a backrest articulation of the system according to the present invention;

- figure 5A is an exemplary diagram of a flexible structure which realizes the backrest according to the present invention;

- figure 5B is a schematic of a column of the flexible structure; - figures 6A, 6B, 6C are exemplary diagrams of a column in three different positions of the apparatus according to the present invention;

-; Figures 7A, 7B and 7C show some examples of configuration of the flexible structure characterized by one or more elements of the columns and realizing the back according to the present invention;

figure 8 shows, by way of example, some elements of the column according to the present invention;

Figure 9A is an exemplary view of an active seat articulated system structure according to the present invention;

- figure 9B shows a schematic example of an articulated active seat system functioning as an aid for mobility; And

- figure 10 is a block diagram of the control system according to the present invention.

Detailed description of the drawings

The present invention will be described in detail below with reference to the figures indicated above.

Referring first of all to figures 1A, 1B, 1C, these schematically illustrate a part of the overall kinematic operation of a system according to the present invention, representing in particular the section according to a lateral / sagittal plane

An active articulated seating system according to the present invention comprises a seating structure 1 comprising two or more portions 2, 3, 4, 5 connected to each other by respective articulations 12, 13, 14. The articulated portions are adapted to be configured according to a starting position.

Advantageously, a backrest portion 2, a seat portion 3, two tibial portions 4 and two breech portions 5 are provided, connected to each other in such a way as to define the seating structure 1 as a whole.

The system is an electronically controlled adjustable segmental active system, suitably articulated, aimed at accommodating and containing the subject, typically in a sitting position.

For this purpose, devices can be provided for locking the subject to the seat structure and / or devices for supporting and supporting his anatomical parts, so as to minimize the possibility of relative motion between the same and the containment structure.

The structure, as mentioned, comprises a backrest portion 2 which, as will be better described below, has degrees of freedom of flexion / extension in the sagittal and frontal planes and of torsion in the transverse plane, all of which can be combined with each other.

Furthermore, the structure comprises a seat portion 3, articulated to the backrest 2 by means of mechanical joints positioned in correspondence with the coxo-femoral (hip) anatomical joint.

Two tibial portions 4 are articulated, each independently, to the seat 3 by means of mechanical joints positioned in correspondence with the anatomical femoro-tibial joint (knee).

Two breech portions 5 are each independently articulated to the respective ipsilateral tibial portion 4 by means of mechanical joints positioned at the ankle joint.

Preferably, all the surfaces in contact with the subject are made of depressible material and with an ergonomic shape. The subject is made integral with the structure by means of locking devices.

Preferably, the mechanical joints which make the joints consist of single axial hinges or systems of axial hinges.

In particular, Figure 1A represents the seat structure 1, in an initial position, suitable for accommodating a seated subject.

The joints 12, 13, 14, actuated by axial hinges, are those of the ankle 14, knee 13 and of the backrest 12. The preferred embodiment for the backrest portion 2 will be described below. It should be noted that it is preferably made up of one or more elastic and flexible elements.

Figure 1B shows the effect of stresses applied to one or more of the portions, for example due to the subject's thrusts on the various parts of the structure.

According to the present invention, the system is able to accommodate these stresses, consequently moving the different portions of the structure. Figure 1C shows, by way of example, a possible final position reached by the structure following stresses.

The following figures 2A, 2B, 2C illustrate the general functioning of an ankle joint.

In particular, figure 2A shows the joint in an initial position. The articulation is preferably made by means of an axial hinge and elastic return means are associated with it, in particular a first damped resilient return element, for example a gas spring. This element is adequately calibrated to recall the two portions (tibial and breech) connected by the joint in the initial position in the absence of stress.

Naturally, two of these joints are provided, and therefore the presence of as many first damped elastic elements of recall is to be expected.

Figure 2B illustrates the effect of external stress on one or more of the portions of the structure associated with the ankle joint. For example, a push exerted by the foot of the subject on the breech portion causes the latter to rotate, compressing the damped elastic element of recall.

Figure 2C illustrates the operation when the stress ceases. In these conditions of absence of stresses, the damped return elastic element returns to prevail, bringing the portions back to their initial position.

It is to be understood that elastic return means can also be associated with the other joints, as will also be described below.

These elastic return means provide a passive reaction to stresses, however, according to the present invention, the system provides that at least one of the structure portions is actively controlled and moved.

For this purpose, the system comprises position and / or force sensors for detecting the stresses which, applied to at least one of the portions of the structure, are such as to move it away from the predetermined initial position.

The movement of the at least one actively controlled portion takes place by means of actuation means.

Therefore, the system provides a control unit capable of receiving data from the sensors and piloting the actuation means according to the data received, so that the portion is moved in such a way as to satisfy the stresses and return in a controlled manner to said initial position in the absence of stresses.

The active control of one or more portions of the structure is such that it can deform congruently to the trajectory imposed by the stresses caused for example by a dystonic event, yielding in a controlled manner until the end of the dystonic event and therefore of the stress.

During the check, the system collects data relating to all the kinematic and kinetic characteristics of the dystonic event, processes them and stores them for any short, medium and long term analyzes.

At the end of the solicitation, the system is such as to move the structure to bring the subject back to the initial position following preferential return trajectories, evaluating the patient's reaction to the new solicitation.

The system is therefore able to monitor one or more degrees of freedom admissible by the mechanical structure in terms of kinematics and kinetics thanks to the force and position sensors. An interface allows you to collect and download the data detected during the dystonic event.

In this way it is possible to verify the â € œcomplianceâ € of the subject and the possible resistance opposed by him during the return to the initial position imposed by the system (possible new dystonic event).

The system allows to collect the following data characterizing the dystonic events: â € ¢ trajectories followed during the dystonic event for each joint,

â € ¢ the forces, powers and stresses associated with it for each joint,

â € ¢ the frequency of occurrence,

â € ¢ the duration of the single event,

â € ¢ the time interval between one event and the next,

â € ¢ patient compliance,

â € ¢ any resistance opposed during the return to the initial position imposed by the system.

The following figures 3A, 3B, 3C refer to a knee joint 13, which connects a tibial portion 4 to the seat portion 3. Naturally, at least two of these joints are also provided.

Figure 3A shows a general scheme of the joint, according to a preferred embodiment of the present invention. The knee joint 13 is obtained via an axial hinge 21.

The actuation means mentioned above therefore comprise, for each of the knee joints, a respective motorized tibial actuator 30 for moving the tibial portion 4.

In particular, according to the embodiment described here as an example, the tibial actuator 30 comprises a motorized rack 31 which, moved by a motor 32, acts on the tibial portion 4. The tibial actuator 30 works in parallel with a damped elastic element 36, for example a gas spring with adjustable pressure (which in this case works in traction) which allows to vary the threshold value at which the joint begins to follow the movement of the subject (displacement from the position of equilibrium ).

Advantageously, a force sensor is provided, for example a load cell 20, placed between the tibial portion 4 and the rack 31. The load cell detects the pressure variations due to the stress caused for example by the movement of the limb of the subject, data that are acquired by the control unit of the system that will process them to determine the control and movement of the portion itself.

For this purpose, the control unit comprises data acquisition means for receiving data from the sensors, means for processing the acquired data and means for driving the actuators as a function of the processed data.

If necessary, it is possible to set non-neutral starting / standard positions (ie with an angle of inclination with respect to the vertical other than 0). Preferably, unlike what is shown in the figures for graphic simplification, the application and rotation fulcrums of the gas spring and of the motor coincide.

The damped elastic return element 36 can also be replaced by an additional motor equipped with mechanical reductions sufficient to prevent unwanted movement of the subject or even by an electromagnetic brake. The choice between the use of the damped return elastic element and / or the mechanical reduction depends on the economic convenience of the solution, which will be evaluated case by case. In both cases the motor is activated only above the thrust threshold set externally, leaving either the reduction or the damped elastic return element to keep the patient in the desired initial position.

Figure 3B shows the effect of a stress caused for example by a push F1 by the subject. The load cell 20 detects the pressure variation and starts the motor 32 which in a first phase accompanies the movement of the subject according to a law pre-established by the medical staff also on the basis of the physiological characteristics of the patient.

The system will record the amplitude of the movement and the intensity of the thrust through the duration, the number of revolutions of the motor (detected for example through a position sensor such as an encoder) and the absorption of the motor in following the structure and through the pressure variations on the load cell 20.

Figure 3C instead shows the return sequence. The load cell 20, detecting the exhaustion of the overthrust by the patient with respect to the initial value F1, will return the tibial portion 4 to the initial position, according to a law pre-set by the medical staff also based on the physiological characteristics of the patient same.

In general, it is preferable that this recall occurs by â € œbrakingâ €, thanks to the application of a calibrated torque, the descent of the tibial portion towards the initial position of rest.

The presence of the load cell allows the thrust of the motor to be inverted again, for example in the event that, during the recall phase, the subject returns to exert a stress such as an extensive thrust of the limb.

The following figures 4A, 4B, 4C refer to a seat articulation, between the seat portion 3 and the backrest portion 2.

Figure 4A shows a general diagram of the articulation 12. The articulation of the backrest is in equilibrium between the thrust F2 of a second damped elastic element 26, for example a gas spring (which in this case works in compression) and the push F1 of the weight of the subject resting on the backrest portion 2.

The articulation hinge 41 between the seat 3 and the backrest 2 creates a fulcrum between the two thrusts.

The system actuation means further comprise a motorized backrest actuator 40 adapted to move the backrest portion 2 with respect to the seat 3.

This actuator provides a motorized rack 42 by means of a motor 43. Also in this case, a force sensor, in particular a load cell 44, is placed between the backrest portion 2 and the rack 42 to detect the pressure variations due to the movement of the subject.

It is possible, if necessary, to set non-neutral starting / standard positions (ie with an angle of inclination with respect to the vertical other than 0). Preferably, unlike what is shown in the figures for graphic simplification, the application and rotation fulcrums of the gas spring and of the motor coincide.

The damped elastic return element 26 can also be replaced by an additional motor equipped with mechanical reductions sufficient to prevent the movement of the subject under load or even by an electromagnetic brake.

The choice between the use of the damped elastic return element and / or the mechanical reduction depends on the economic convenience of the solution, which will be evaluated case by case. In both cases the motor is activated only above the thrust threshold set from the outside, leaving either the reduction or the damped elastic return element the task of keeping the patient in a static position

Figure 4B shows the effect of a stress caused for example by a push F1 '> F1 by the subject. The load cell 44 detects the pressure variation and starts the motor 43 which in a first phase accompanies the movement of the subject according to a law pre-established by the medical staff also on the basis of the physiological characteristics of the patient.

The system will record the amplitude of the movement and the intensity of the thrust through the duration, the number of revolutions of the motor (detected for example through a position sensor such as an encoder) and the absorption of the motor in following the patient's back and through the variations of pressure on the load cell 44.

Figure 4C instead shows the return sequence. The load cell 44, detecting the exhaustion of the overthrust by the patient with respect to the initial value F1, will return the backrest 2 to the initial position, according to a law pre-set by the medical staff also based on the physiological characteristics of the patient himself .

The presence of the load cell makes it possible to reverse the thrust of the motor again, in the event that the patient returns to give a stress, for example through an extensive thrust of the trunk with respect to the lower limbs.

The following figures 5A and 5B are a schematic representation of a flexible structure 50, which forms the backrest portion, according to a preferred embodiment of the present invention.

The flexible structure 50 is, according to the invention, able to undergo elastic deformations, due to external stresses or actively determined by the system. For this purpose, the actuation means comprise one or more motorized structure actuators 51, adapted to elastically deform the backrest portion 2 along three orthogonal axes in space. This is achieved, for example, by means of two motorized structure actuators 51, which can be operated independently.

Each of these actuators 51 comprises an elastic and flexible column 53, having means 54, 55, 56, 57 for adjusting the flexibility, in turn controlled by the control means of the system.

Each elastic and flexible column 53 develops along an axial direction and comprises a succession of rigid modules 55 and elastic modules 56 alternating along this axial direction, better schematized in the following figures 6A, 6B, 6C and of which figure 8 shows an example.

The elastic modules 56, schematized in Figures 6A, 6B and 6C, can undergo compression along the axial direction, compression determined by the flexibility adjustment means 54, 55, 56, 57 in such a way as to give the column 53 a specific degree of flexibility and thus allow it to sag by default. By way of example, according to the present invention, the means for adjusting the flexibility comprise a tie rod 54 passing inside said column 53 and fixed to one end 58 of this. The tie rod 54 is pulled or released by a motor 57 located at the opposite end 59 of the column 53, as shown schematically in figure 5B.

The stresses applied on the columns by the motor and by the patient are detected by a load cell inserted at the extremity 59. The values of the stresses, in addition to being recorded, allow the electronic card to control the motors in order to vary the flexibility of the columns and allow for a controlled compliance and return in torsion and flexion of the backrest

The variation of the cable tension allows a uniformly distributed variation of the spatial distribution of the sequence of modules. The system may possibly include a position detection system, for example a gyroscope 60.

Figure 6A represents a general diagram of the backrest operating system and Figure 6B shows it in the initial position in which the cable is tensioned and therefore allows the columns to be stiffened and a vertical and straight position to be maintained. The traction of the cable balances the usual thrust of the trunk at rest, resting on the backrest.

Figure 6C shows how, due to a stress due for example to a thrust of the trunk, the motor 57 loosens the tie rod 54, allowing a deformation in the spatial arrangement of the rigid modules 55. The alternation with the elastic modules 56, suitably chosen for materials, stiffness coefficients and structural profile, it ensures a continuous and distributed deformation of the profile of the columns 53, deformation controlled instant by instant by the force and position sensors (eg gyroscope and load cell).

As illustrated by way of example in figures 7A, 7B and 7C, the backrest structure can include two columns 53. Being autonomous and independently implemented, each column deforms in a different way, to follow bending, extensional and torsional movements, even asymmetrical, of the subject.

The modular system of the backrest, being able to deform uniformly along the three axes in space, also allows to follow geometrically lateral rotations of the back in combination with contractions or hyperextensions.

Figure 8 shows an example of construction of a column 53. More precisely in figure 8 some of the rigid modules 55 are represented, but the elastic module 56 is not represented, which can be constituted by a single compression spring, by a series of compression springs in series or in parallel or by a rubber ring with variable stiffness, by a piston, etc. The lower module indicated with 105 represents a first module of the elastic column 53, preferably arranged for anchoring to the part of the backrest 2 which is hinged with the seat 3.

Figure 9A shows, by way of example, a seating system 100 according to the present invention. Figure 9B represents a variant in which the seating system 100 is mounted on a special structure capable of constituting as a whole also an aid for mobility.

In addition to what has been described up to now, the seating system 100 can also comprise devices for locking the subject to the seating structure. In particular, locking devices can be provided at the level of the tibial portions and of the backrest portion, in such a way that the subject is bound to keep his body constantly resting on the structure.

Figure 10, on the other hand, schematically illustrates the main components of the control unit and of the means for controlling and regulating the actuators.

In particular, it is indicated the detection of the pressure signals by a force sensor (load cell) which, suitably amplified, is input to a driving circuit which powers a motor. Advantageously, an encoder is provided for detecting the position of the motor, by detecting its rotation.

A personal computer, through a dedicated software, provides for the acquisition of data, their storage and their processing to determine the commands to be given to the driving circuit so that the actuators are piloted in the right way to ensure that the structure follows the predefined and desired trajectories based on the stresses received.

In particular, the processing means may also be suitable for performing one or more of the following functions:

to. set the starting position;

b. set a set of threshold values for comparison above which the system reacts following the patient's movement imposed by the dystonia.

c. set the different kinematic parameters (speed, acceleration, response time) and kinetics (torque applied by the actuators both in the accompanying phase of the dystonic movement and in the phase of return to the initial position once the dystonia is over); And

d. memorize the system usage data in order to characterize the dystonic events and use them to refine the calibration of the system on the specific characteristics of the user patient.

The present invention has been described up to now with reference to a preferred embodiment thereof. It is to be understood that other embodiments may exist which pertain to the same inventive nucleus, all falling within the scope of the protection of the claims set forth below.

Claims (20)

CLAIMS 1. Articulated active seating system (100), comprising: - a seating structure with variable geometry (1) comprising two or more portions (2, 3, 4, 5) connected to each other through respective joints (12, 13, 14), capable of being configured according to an initial position; - position and / or force sensors (20, 44, 60) to detect configurations and stresses which, applied to at least a portion of said two or more portions (2, 3, 4, 5), are such as to move it away and / or bring it closer to said initial position; - actuation means (30, 40, 51) for moving said at least one portion; - a control unit capable of receiving data from said sensors and piloting said actuation means as a function of said data, so that said at least one portion is moved in such a way as to accommodate said stresses and return to said initial position in the absence of stresses . System (100) according to claim 1, comprising elastic return means (6, 26, 36) associated with at least one of said joints (12, 13, 14), and adapted to recall the portions connected through said joint in said starting position. System according to claim 1 or 2, wherein said joints (12, 13, 14) are made by means of axial hinges or axial hinge systems. System according to one of claims 1 to 3, wherein said two or more portions comprise a backrest portion (2), a seat portion (3), two tibial portions (4) and two breech portions (5), connected to each other in such a way as to define said seating structure (1). 5. System according to claims 2 and 4, wherein said elastic return means (6, 26, 36) comprise first damped elastic elements (6) connected between said tibial portions (4) and said breech portions (5). 6. System according to claims 2 and 4, or claim 5, wherein said elastic return means (6, 26, 36) comprise a second damped elastic element (26) connected between said backrest portion (2) and said portion seat (3). System according to claims 2 and 4, or claim 5 or claim 6, wherein said elastic return means (6, 26, 36) comprise third damped elastic elements (36) connected between said seating portion (3) and said tibial portions (4). System according to one of claims 4 to 7, wherein said actuation means (30, 40, 51) comprise motorized tibial actuators (30) respectively adapted to move said tibial portions (4). System according to one of claims 4 to 8, wherein said actuation means (30, 40, 51) comprise a motorized backrest actuator (40) adapted to move said backrest portion (2). System according to one of claims 4 to 9, wherein said backrest portion (2) is made with a flexible structure (50) capable of undergoing elastic deformations. 11. System according to claim 10, wherein said actuation means (30, 40, 51) comprise one or more motorized structure actuators (51), adapted to elastically deform said flexible structure (50). System according to claim 11, comprising two motorized structure actuators (51), which can be operated independently, such that their combined actuation is capable of elastically deforming said flexible structure (50) along three orthogonal axes in space. System according to claim 11 or 12, wherein each of said motorized structure actuators (51) comprises an elastic and flexible column (53), having means for adjusting the flexibility (54, 55, 56, 57) controlled by said control means. System according to claim 13, in which each elastic and flexible column (53) develops along an axial direction and comprises a succession of rigid modules (55) suitably profiled and elastic modules (56) alternated along this axial direction, said modules elastic bands (56) being able to undergo compression along this axial direction by said flexibility adjustment means, in such a way as to give the column a specific degree of flexibility. 15. System according to claim 13 or 14, wherein said means for adjusting the flexibility comprise a tie rod (54) passing inside said column (53) and fixed to one end (58) of this, said tie rod being pulled or released by a motor (57) at the opposite end (59) of the column (53). 16. System according to claim 15, wherein said position and / or force sensors comprise a load cell positioned in such a way as to measure a force applied to the flexible column (53) and in particular to the tie rod (54), to allow to the control means for driving the motor (57). System according to one of claims 5 to 15, wherein said first, second and third damped elastic elements (6, 26, 36) are gas springs. System according to one of claims 1 to 17, further comprising devices for locking a person to the seating structure (1). 19. System according to one of claims 1 to 18, wherein said control unit comprises data acquisition means for receiving data from said sensors, means for processing said acquired data and means for driving said actuators as a function of said processed data . 20. System according to claim 19, wherein said processing means are adapted to perform one or more of the following functions: â € ¢ set said initial position; â € ¢ set a set of threshold values for activating the actuators; â € ¢ set kinematic and kinetic parameters; â € ¢ store system usage data.