EP2881008A1

EP2881008A1 - Walk training apparatus, and use thereof.

Info

Publication number: EP2881008A1
Application number: EP13196260.7A
Authority: EP
Inventors: Sebastiaan Maria BEHRENS; Hendrik Carsten Voort; Adrianus Hubertus Arno Stienen; Khalid Abdulrahman Aldakkan; Herman Van Der Kooij
Original assignee: Twente Universiteit; King Abdulaziz City for Science and Technology KACST
Current assignee: Gable Systems Bv; King Abdulaziz City for Science and Technology KACST
Priority date: 2013-12-09
Filing date: 2013-12-09
Publication date: 2015-06-10

Abstract

A walk training apparatus (1) comprises a main frame (10); a rolling assembly (4), allowing the main frame to perform omnidirectional rolling movements over a floor during walking of a person (11); a drive unit (5) for driving the rolling assembly; a sensor (6) for detecting relative translational and/or rotational movement and/or relative force and/or torque exertion between a body reference part (12) of the person's body and a frame reference part (2, 3) of the main frame; a calculator (7) for calculating drive control parameters based on detection results from the sensor; and a controller (8) for controlling the drive unit based on the calculated drive control parameters.

Description

The invention relates to a walk training apparatus, and to the use thereof.
The walk training apparatus according to the invention can be used for training walking and/or balance of persons. Such a training is useful in different cases.
One case of use of a walk training apparatus according to the invention relates to patients with gait abnormalities, e.g. stroke patients. This kind of patients have significant benefit of gait training therapy. Common gait training methods for gait rehabilitation are very demanding for therapists. Usually one or more therapists are needed to support and guide one patient during walking, whether or not the patient is additionally aided by some known supporting and/or training apparatus (such as a treadmill). Also, for such a therapist assisted gait training method to be effective, long-lasting gait training exercises have to be performed frequently over long time periods. Therefore, effective common gait training methods are very labour-intensive and expensive. Also, the character and quality of the therapist's training method may vary from day to day, and from therapist to therapist. Furthermore, different patients need different training methods, while a training method for a given patient has to be gradually/frequently updated in view of the patient's changing walking abilities over time. These changing abilities may involve progress or, e.g. in case of a degenerative disease of the patient, degeneration. In summary, therapist assisted training methods have various and many drawbacks.
An example of another case of use of a walk training apparatus according to the invention is the non-therapeutic use for training the walking of a toddler or baby at a natural learning-to-walk age (or, more generally, a person at the age between about 6 and about 30 months, or, yet more generally, a person at the age of less than 2.5 or 3 years old). When parents, attendants, or the like assist a young child by supporting and guiding the child during walking, similar drawbacks are experienced, as mentioned above for therapist assisted training of patients. In some respects, the drawbacks in general are even higher than in the therapist assisted case, since most of the parents, attendants, or the like, are missing the specialized educational background and experience that a professional therapist usually has.
An example of yet another case of use of a walk training apparatus according to the invention is the non-therapeutic use for training sportspeople, or the like, in performing predetermined leg movement patterns/step sequences, or the like. Examples are step sequences to be trained by athletes in certain disciplines of athletics, or step sequences to be trained by dancers for performing a certain dance programme.
It is an object of the invention to provide a solution according to which the training of walking and/or balance of a person is improved in respect of effectiveness, reliability and said person's safety, while reducing the dependency of human assistance in said training.
For that purpose, the invention provides a walk training apparatus, which can be brought in a reference condition in which the apparatus is resting on a horizontal reference floor, and wherein the apparatus, as considered in said reference condition, comprises:

a main frame providing a possibility for a person to receive support, via the main frame, during walking of said person over said floor;
a rolling assembly, being attached to the main frame and allowing the main frame to perform possible rolling movements over said floor during said walking of said person, said possible rolling movements including omnidirectional translations and/or rotations over said floor;
at least one drive unit for driving the rolling assembly for realizing said possible rolling movements of the main frame;
at least one sensor, configured, arranged and effective to detect relative translational and/or rotational movement and/or relative force and/or torque exertion between a body reference part of the body of said person and a frame reference part of said main frame;
at least one calculator, which is communicatively connected to said at least one sensor and which is configured, arranged and effective to calculate, based on detection results obtained by said at least one sensor, at least one drive control parameter for controlling said at least one drive unit to realize specific translative and/or rotative movement of said possible rolling movements; and
at least one controller, which is communicatively connected to said at least one calculator and which is configured, arranged and effective to control said at least one drive unit based on said at least one drive control parameter.

The advantageous working of this apparatus according to the invention is elucidated as follows. Thanks to the rolling assembly, which is driven under calculated control based on detected actually present conditions of mutual orientation and/or of mutual force exertion between person and apparatus, said actually present conditions are automatically and reliably updated into conditions being more effective for the walk training and/or being more safe for the person. During all that, omnidirectional movements over the floor may be performed, not only by the main frame, but also by the person being trained. Since the apparatus according to the invention involves control feed-back between the apparatus and the person being trained, and vice versa, the invention in this respect is based on reciprocal interactions, which are similar to the natural reciprocal human interactions between an assisting human and an assisted human. As the apparatus according to the invention comprises automatic means for sensing, calculating and controlling, the apparatus in fact is even more powerful (in terms of reaction speed, calculation power, memory, etc.) than an assisting human. Thus, the apparatus according to the invention eliminates or at least reduces the need for human assistance in the training.
In principle, the apparatus according to the invention may be used without physical contact between the apparatus and the (assisted) person. That is, the person may for example walk loose from the apparatus, while distance sensors of the apparatus continuously measure distances/orientation of the person relative to the apparatus, based on which the main frame is controlled to move in such manner that the apparatus closely follows the walking person. In that case, should the person at any time need or wish to find support from the apparatus, the person can for example always hold himself or herself onto the apparatus.
In a preferable embodiment of an apparatus according to the invention, the apparatus, as considered in said reference condition, further comprises a moveable body support structure, which moveable body support structure has a body support condition in which the moveable body support structure is contactingly supporting said person, the moveable body support structure being attached to the main frame in a translationally and/or rotationally moveable manner relative to the main frame such that, during said walking of said person in said body support condition, the moveable body support structure at least partly follows said body reference part in said relative translational and/or rotational movement between said body reference part and said frame reference part.
Via such a moveable body support structure, the relative translational and/or rotational movement and/or relative force and/or torque exertion between the body reference part of the person and the frame reference part of the main frame, can be reliably detected. Additionally, via such a moveable body support structure, supportive forces and/or torques can be transmitted from the apparatus to the person.
Preferably, as considered in said reference condition, said moveable body support structure comprises a body weight carrier, which body weight carrier has a body weight support condition in which the body weight carrier is carrying body weight of said person, the body weight carrier being attached to the main frame in a moveable manner relative to the main frame such that, during said walking of said person in said body weight support condition, the body weight carrier at least partly follows said body reference part in said relative translational and/or rotational movement between said body reference part and said frame reference part. Such a body weight carrier may for example be a trunk support device, e.g. in the form of a harness. Also, such a body weight carrier may for example be a seat which is supporting the pelvis area of said person when said person is sitting on the seat. Such a seat (e.g. in the form of a saddle) is very effective in carrying body weight of the person, while at the same time allowing the legs of the person to perform walking movements. Additionally, when using such a seat, at least part of the contact surface of the pelvis area, which contact surface is actually contacting the seat, may be considered as the abovementioned "body reference part of the body of said person" or as part thereof, which promotes the reliability of the detection results obtained by the sensor.
More preferably, as considered in said reference condition, said moveable body support structure further comprises a constant force mechanism, and said moveable manner in which the body weight carrier is attached to the main frame comprises a vertical moveability component in that the body weight carrier is attached to the main frame in at least a vertically moveable manner relative to the main frame such that, during said walking of said person in said body weight support condition, the body weight carrier at least partly follows said body reference part in its relative vertical movement between said body reference part and said frame reference part, and said vertically moveable manner in which the body weight carrier is attached to the main frame is realized by means of said constant force mechanism which, during said walking of said person in said body weight support condition, provides an upwardly directed supporting force which is constant throughout a vertical movement range of the vertical movement component of the body weight carrier relative to the main frame.
Since walking of a person involves, to a moderate extent, reciprocating up and down movements of the trunk of a person, said constant force mechanism provides an upwardly directed supporting force for carrying body weight of the person, which upwardly directed supporting force is constant during said reciprocating up and down movements of the trunk of the person. This especially is advantageous for persons having insufficient capacity for carrying their own body weight all by themselves. However, said application of the constant force mechanism is useful, or at least comfortable, for any person.
It is noted that instead of, or in addition to, said constant force mechanism said moveable body support structure may also comprise a controlled active lift system and/or an oscillating spring-mass system, wherein the natural frequency of the spring-mass system may be tuned to match the walking frequency of the person.
Another preferable embodiment of an apparatus according to the invention, which can be used in combination with any one of the abovementioned embodiments of the invention, is specified by the additional features that, as considered in said reference condition, said moveable body support structure comprises elastic structure for realizing, in an elastic manner, said translationally and/or rotationally moveable manner in which said moveable body support structure is attached to the main frame. By thus realizing said attachment in an elastic manner, the reliability and effects of the resulting controlled driving of the rolling assembly are further improved.
Preferably, as considered in said reference condition, the at least one calculator is configured, arranged and effective to calculate said at least one drive control parameter based on a combination of (i) relative translational and/or rotational movement, detected by said at least one sensor, and (ii) elastic translational and/or torsional stiffness of said elastic structure. Considering that said elastic translational and/or torsional stiffness of said elastic structure is a priori known, the relative forces and/or relative torques between the body reference part and the frame reference part can reliably be derived by combining (i) and (ii). Hence, said combining of (i) and (ii) improves the reliability of the controlled driving of the rolling assembly, which enables the apparatus to reliably support the person's stability at all times.
It is noted that instead of, or in addition to, the application of said elastic structure the relative forces and/or relative torques between the body reference part and the frame reference part may also be derived by the application of one or more load cells.
In another preferable embodiment of an apparatus according to the invention, which can be used in combination with any one of the abovementioned embodiments of the invention, the apparatus, as considered in said reference condition, further comprises at least one adjustor, which is communicatively connected to said at least one calculator and which is configured, arranged and effective (i) to receive an adjustment instruction, and (ii) to adjust said at least one calculator, based on said adjustment instruction, into different operation modes of the walk training apparatus, by adjusting the way in which said at least one drive control parameter is calculated based on said detection results obtained by said at least one sensor.
Said adjustor, which enables adjustment into said different operation modes, provides the advantage that different training methods can be offered to different patients, while a training method for a given patient can be updated over time in view of the patient's changing walking abilities over time. It is noted that more in general, instead of the application of such an adjustor enabling adjustment into said different operation modes, an apparatus according to the invention may in principle be arranged for only a single specific operation mode, such as one of the specific operation modes described below (first operation mode, second operation mode, third operation mode).
Preferably, as considered in said reference condition, said different operation modes of the walk training apparatus, obtainable by said adjusting of said at least one calculator, comprise:

a first operation mode, during which first operation mode said at least one drive control parameter is calculated to control said at least one drive unit to drive the rolling assembly such that the main frame performs rolling movements over said floor according to a predetermined rolling trajectory, thus imposing a correspondingly predetermined walking trajectory to said person; and
a second operation mode, during which second operation mode said at least one drive control parameter is calculated to control said at least one drive unit to drive the rolling assembly in such manner that a voluntary walking trajectory performed by said person over said floor imposes an obedient rolling trajectory of the main frame, wherein said obedient rolling trajectory of the main frame relative to said floor, in terms of shape and position dependent speed, is substantially the same as the vertical projection onto said horizontal floor of the trajectory of said body reference part relative to said floor caused by said voluntary walking trajectory performed by said person.

By means of said first operation mode the apparatus imposes a predetermined walking trajectory to the person. Such a predetermined walking trajectory may for example be imposed by selecting a predetermined rolling trajectory from several different such predetermined rolling trajectories stored on an electronic storage device. Thus a predetermined walking trajectory can be offered to the person, which is deemed suitable for a specific person at a specific time. The person has to follow more or less the (omnidirectional) predetermined rolling trajectory of the main frame. Such a first operation mode may be suitable for many different walking skill levels of persons, since a predetermined "high skill" rolling trajectory may be chosen for a person with high walking skills, while a predetermined "low skill" rolling trajectory may be chosen for a person with low walking skills.
By means of said second operation mode, on the other hand, the main frame more or less automatically follows the person, when the person voluntarily performs a walking trajectory, which is chosen voluntarily by said person. Since the main frame follows the person, it is always readily available for supporting the person. Just as for the first operation mode, such a second operation mode may also be suitable for many different walking skill levels of persons. The reason is that in the second operation mode the main frame automatically follows the person, which means that the main frame automatically follows for example a slow walking speed and/or easy walking trajectory of a person with low walking skills just as easy as a high walking speed and/or difficult walking trajectory of a person with high walking skills.
More preferably, as considered in said reference condition, said different operation modes of the walk training apparatus, obtainable by said adjusting of said at least one calculator, further comprise:

at least one third operation mode, during which third operation mode said at least one drive control parameter is calculated to control said at least one drive unit to drive the rolling assembly such that the main frame performs rolling movements over said floor according to a part of a predetermined rolling trajectory as defined for said first operation mode, thus only partly imposing a correspondingly predetermined walking trajectory as defined for said first operation mode to said person, while allowing said person to partly perform a voluntary walking trajectory as defined for said second operation mode, thus only partly imposing said obedient rolling trajectory as defined for said second operation mode.

Such a third operation mode is more or less a combination of parts of the first operation mode and parts of the second operation mode. Such a third operation mode can in general be said to offer the "the best of both worlds" advantages. Such a third operation mode could for example be implemented so as to start a predetermined rolling trajectory of the main frame, which the person in principle has to follow. However, should the person at some point in time decide to deviate from the predetermined rolling trajectory of the main frame, for example by deciding to voluntarily perform a left or right turn walking traject, the main frame will follow the person in that left or right turn walking traject. For similar reasons as explained above for the first and second operation modes, such a third operation mode may also be suitable for many different walking skill levels of persons.
In another preferable embodiment of an apparatus according to the invention, which can be used in combination with any one of the abovementioned embodiments of the invention, the apparatus, as considered in said reference condition, further comprises a leg actuation mechanism, which leg actuation mechanism has a leg actuation condition in which the leg actuation mechanism is being controlled to supportingly guide the legs of said person in performing walking movements by said person. Combining such a leg actuation mechanism, having the said leg actuation condition, with the above explained main features of the invention (which provide automated reciprocal interactions between apparatus and person, as explained) provides important synergistic effects. These synergistic effects mainly have to do with the fact that, where known mechanized leg actuation in practice often fails to provide its intended effects, the reliability and security offered to the person by the automated reciprocal interactions between the apparatus and the person (as according to the present invention) provides the person with the comfortable and safe feelings needed to entrust himself or herself to the mechanized leg actuation. Next, when thus allowing and experiencing the mechanized leg actuation, the person's trust, as well as the person's "learning curve" receive further boosts, yet unseen when using common devices. This kind of synergistically favourable "trust boosts" are in fact only comparable to a situation like wherein the hands of a young child, which fully trusts and relies on its parents, are held by its mother's hands, while at the same time its father's hands are guidingly moving its legs.
Preferably, as considered in said reference condition, said at least one calculator is configured, arranged and effective to calculate, based on detection results obtained by said at least one sensor, at least one leg actuation control parameter for controlling said leg actuation mechanism to realize said supportingly guiding the legs of said person, and wherein said at least one controller is configured, arranged and effective to control said leg actuation mechanism based on said at least one leg actuation control parameter. This additional automated feed-back interaction, this time by automatically controlling also the leg actuation mechanism based on the detection results, further improves the training results by further improving basis of trust and learning curve, as explained above.
In another preferable embodiment of an apparatus according to the invention, which can be used in combination with any one of the abovementioned embodiments of the invention, the apparatus is dimensioned to be used when said person is a person at the age of less than two and a half years old, and/or, in other words, when said person is a toddler or baby at a natural learning-to-walk age. The availability of such an apparatus for this kind of young children, which apparatus could be referred to as a small "intelligent walking bicycle", or the like, provides young children with an attractive "playing" device, which teaches them to walk very quickly.
The invention may also be embodied in a use of a walk training apparatus according to any one of the abovementioned embodiments of the invention, for training the walking and/or balance of a person.
A preferable embodiment of a use according to the invention is a non-therapeutic use of a walk training apparatus according to any one of the abovementioned embodiments of the invention, for training the walking of a person at the age of less than two and a half years old, and/or, in other words, for training the walking of a toddler or baby at a natural learning-to-walk age.
These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter by way of non-limiting examples only and with reference to the schematic figures in the enclosed drawing.

Fig. 1 shows, in a perspective view, an example of an embodiment of a walk training apparatus according to the invention, in the said reference condition of the apparatus, and during use of the apparatus for training the walking of a person.
Fig. 2 shows the picture of Fig.1 again, wherein the image of said person has been omitted for providing a better view at certain parts of the apparatus.
Fig. 3 shows part of the apparatus and person of Fig. 1 in a highly schematical perspective view, wherein, for reasons of simplicity, at least the leg actuation mechanism has been omitted from Fig. 3.

In these Figures, the apparatus according to the invention is indicated by reference numeral 1, while in Figs. 1 and 3 reference numeral 11 denotes the said person, which has been depicted in Fig. 3 extremely schematically by means of the shown body of mass, i.e. the ball 11. In Figures 1-3, the apparatus 1 is in the said reference condition, in which the apparatus 1 is resting on a horizontal floor. Throughout the respective Figures 1-3, like reference numerals denote like parts or aspects.
It is noted that the main dimensions and equipment level of the example of the apparatus shown in Figs. 1 and 2 are suitable for use in environments such as, e.g., hospitals or other similarly large therapeutic or non-therapeutic environments. However, in general, an apparatus according to the invention may have smaller main dimensions and/or a more simple equipment level than the apparatus shown in Figs. 1 and 2, e.g. for use in home-like environments or for outdoor use. Also, an apparatus according to the invention may be integrated into the design of products such as a wheel chair, rollator, walking bicycle, etc.
Below, reference is mainly made to the highly schematical Fig. 3, while assistingly referring now and then to Figs. 1 and 2. In Figs. 1 and 3 the three orthogonal directions x, y, z have been indicated, of which x and y are horizontal directions and z is a vertical direction.
The following main parts of apparatus 1 are shown in Fig. 3: said main frame 10, consisting of vertical beam 2 and horizontal beam 3, beams 2 and 3 being interconnected; said rolling assembly 4; said (at least one) drive unit 5; said (at least one) sensor 6; said (at least one) calculator 7; and said (at least one) controller 8. It is noted that, in the shown example, (part of) beam 2 or (part of) beam 3 may function as the abovementioned "frame reference part" of the main frame 10. For simplicity, it has been chosen hereinafter to indicate this frame reference part as "frame reference part 2".
The rolling assembly 4 has been depicted in Fig. 3 extremely schematically by means of three rolling balls 44. Various types of rolling assemblies allowing for the stated omnidirectional translations and/or rotations over a floor, as well as various types of corresponding drive units therefor, are usable in the present invention. Various such omnidirectional rolling assemblies with drive units, ranging from very simple to highly sophisticated/accurate types, are known and available in the trade. In the example of Fig. 1, although not visible in the specific perspective view because of the shown housing parts 42, 43 of the apparatus 1, the rolling assembly 4 comprises four individual rolling units, which are situated more or less near four corner points, respectively, of an imaginary horizontally oriented rectangle at the very bottom of the apparatus 1. Corresponding drive units are also covered by these housing parts 42, 43. Starting from a stand-still position the rolling assembly 4 may for example be driven to rotate the apparatus 1 around an imaginary vertical rotation axis (z-direction), without the apparatus 1 performing any horizontal translation at all. Also, starting from a stand-still position the rolling assembly 4 may for example be driven to purely translate, e.g. purely translate sideways (y direction) or purely translate forward/backward (x direction), or purely translate in any possible inclined horizontal direction relative to the x and y directions. All these kind of translations and rotations may also be combined with one another so as to in fact obtain any possible rolling trajectory of the apparatus 1, said trajectory having time-dependently varying directions and/or speeds of said translations and/or rotations relative to the floor.
The following further parts of apparatus 1 are shown in Fig. 3: said moveable body support structure 14-22; said seat 14; said constant force mechanism 21; said elastic structure 19, 20; and said (at least one) adjustor 9.
The seat 14 is best seen in Fig. 2, while its body weight support condition, which condition is shown in Figs. 1 and 3, is best appreciated in Fig. 1. In the body weight support condition the seat 14 is supporting the pelvis area of person 11, which pelvis area is indicated by reference numeral 12 in Fig. 3.
In the shown example, this pelvis area 12 also functions as the abovementioned "body reference part", while the body weight support condition of the seat 14 corresponds to the body support condition of the moveable body support structure 14-22.
The moveable body support structure 14-22 comprises horizontal beams 15, 16, 17, and a vertical beam 18. The schematic units 22, shown in Fig. 3, indicate translative moveability of the shown parts relative to one another. The elastic structure 19, 20 may for example be formed by two helical springs 19 and 20. Preferably the spring stiffness of springs 19, 20 is adjustable (indicated by the shown crossing arrows of parts 19, 20). Also the upwardly directed supporting force provided by the constant force mechanism 21 preferably is adjustable (indicated by the shown crossing arrow of part 21). Note that part 21 shown in Fig. 3 is not a beam, like the beams 15-18, but part 21 comprises (re)windable belt structure, allowing beams 15, 16, 17, 18 to vertically move relative to upper beam 3 (for this moveability see the schematic units 22 between beam 2 and beam 18). The mentioned belt structure of part 21 will be better appreciated when looking at reference numeral 21 in Fig. 2. It is furthermore noted that various types of constant force mechanisms, known and available in the trade, are usable in the present invention for providing constant force in a movement range in the manner as stated.
From the schematical Fig. 3 it will readily be appreciated that the seat 14, relative to main frame 10, can move back and forth: in x-direction, in y-direction, and in z-direction. During walking of the person 11, this back and forth moveability in z-direction allows for the reciprocating up and down movements of the pelvis area 12 of the person 11 relative to the floor, while at the same time the constant force mechanism 21 provides the stated upwardly directed constant supporting force for carrying body weight of the person. Furthermore, during walking of the person 11, these back and forth moveabilities in x-direction and in y-direction allow for accurately detecting, by the sensor 6, various characteristics of these back and forth moveabilities. The sensor 6 may for example detect relative translational displacements between beam 14 and beam 15, and/or between beam 16 and beam 17, and/or between beam 2 and beam 18.
Based on the detection results thus obtained, the calculator 7 calculates drive control parameter(s), preferably based on a combination of the detected relative translational movement, and the a priori known spring stiffnesses of the helical springs 19 and 20. Based on the calculated drive control parameter(s), the controller 8 controls drive unit 5 to drive the rolling assembly 4.
As mentioned, Fig. 3 furthermore shows the adjustor 9. Adjustor 9 can receive adjustment instructions, for example from an operator who enters these adjustment instructions via an interface, such as a keyboard 41 (see Fig. 1). Adjustor 9 is communicatively connected to calculator 7 and is able to adjust calculator 7, based on the received adjustment instructions, into different operation modes of the walk training apparatus 1, such as the abovementioned "first operation mode", "second operation mode", and "third operation mode". Note that Fig. 1 furthermore shows a display unit 40, from which an operator can read various characteristics, for example of the (operational) status of the apparatus 1 and/or the person 11.
Note that Figs. 1 and 2 show some further (optional) supporting devices providing the person 11 with additional possibilities to receive support from the apparatus 1. In the shown example, these further supporting devices include a trunk support 52 and a handlebar 53.
Figs. 1 and 2 also show the leg actuation mechanism 30. In the shown example, the leg actuation mechanism 30 has two, mutually symmetrical parts, one being a left leg actuation mechanism, the other being a right leg actuation mechanism. The left leg actuation mechanism comprises beam assemblies 31, 32, 33, 34 (see Fig. 2). Beam assembly 31 at one end has a lower leg gripping means for gripping the lower leg of the left leg of the person 11. Beam assembly 32 at one end has an upper leg gripping means for gripping the upper leg of the left leg of the person 11. Beam assembly 33 at its two opposite ends has two pivoting joints, respectively, one of which interconnects beam assembly 33 with beam assembly 31 in a pivotable manner, the other interconnecting beam assembly 33 with beam assembly 32 in a pivotable manner. The joint that interconnects beam assemblies 33 and 32 is furthermore pivotably connected to one end of beam assembly 34, while the other end of beam assembly 34 is connected to drive structure (located within housing 42) of the left leg actuation mechanism. Each of beam assemblies 31, 32, 33, 34 has a multiplicity of internal beams (not shown in Figs. 1 and 2). The multiplicities of internal beams of the respective beam assemblies 31, 32, 33, 34 form three-dimensional parallelogram constructions (note that three-dimensional parallelogram constructions are known in mechanics). Thanks to these three-dimensional parallelogram constructions, the beam assemblies 31, 32, 33, 34 can be driven by the drive structure of the left leg actuation mechanism to move in such manner that the lower leg gripping means and the upper leg gripping means perform mutual movements which correspond to the desired mutual movements of the upper leg and lower leg of the person 11 during walking.
As mentioned, the apparatus according to the invention may have different operation modes, including (but not limited to) the abovementioned "first operation mode", "second operation mode", and "at least one third operation mode". However, it is clear that according to the invention various other different operation modes are possible as well. For example, operation modes may be realized in which a therapist (or other operator) may perform real-time variable control of the rolling assembly and/or of the leg actuation mechanism (with the aid of various interface means, which may e.g. include wire-less control means), depending on the therapist's expertise and views and tailored to the person's actual responsive behaviour. Hence, the invention allows therapists/operators to directly control the movements of the patient (or other person), while the apparatus provides options for guiding and physically supporting the patient.
In the foregoing specification, the invention has been described with reference to a specific example of an embodiment of the invention. However, various modifications and changes may be made therein without departing from the broader scope of the invention as set forth in the appended claims. For example, in the shown example embodiment the moveable body support structure is attached to the main frame in a translationally moveable manner relative to the main frame. Alternatively or additionally (and as reflected in the appended claims), the moveable body support structure may also be attached to the main frame in a rotationally (elastically) moveable manner relative to the main frame. Such rotational moveability may include rotational moveability around any possible direction in three-dimensional space, including rotational moveability around the shown x-direction, y-direction, or z-direction. For example, the saddle 14 (see Fig. 2) may be (elastically) rotationable around the z-axis. The specifications and drawings are, accordingly, to be regarded in an illustrative rather than in a restrictive sense. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word 'comprising' does not exclude the presence of other features or steps than those listed in a claim. Furthermore, the words 'a' and 'an' shall not be construed as limited to 'only one', but instead are used to mean 'at least one', and do not exclude a plurality.

Claims

Walk training apparatus, which can be brought in a reference condition in which the apparatus (1) is resting on a horizontal reference floor, and wherein the apparatus, as considered in said reference condition, comprises:
- a main frame (10) providing a possibility for a person (11) to receive support, via the main frame, during walking of said person over said floor;

- a rolling assembly (4), being attached to the main frame and allowing the main frame to perform possible rolling movements over said floor during said walking of said person, said possible rolling movements including omnidirectional translations and/or rotations over said floor;

- at least one drive unit (5) for driving the rolling assembly for realizing said possible rolling movements of the main frame;

- at least one sensor (6), configured, arranged and effective to detect relative translational and/or rotational movement and/or relative force and/or torque exertion between a body reference part (12) of the body of said person and a frame reference part (2, 3) of said main frame;

- at least one calculator (7), which is communicatively connected to said at least one sensor and which is configured, arranged and effective to calculate, based on detection results obtained by said at least one sensor, at least one drive control parameter for controlling said at least one drive unit to realize specific translative and/or rotative movement of said possible rolling movements; and

- at least one controller (8), which is communicatively connected to said at least one calculator and which is configured, arranged and effective to control said at least one drive unit based on said at least one drive control parameter.
Walk training apparatus according to claim 1, wherein the apparatus (1), as considered in said reference condition, further comprises a moveable body support structure (14-22), which moveable body support structure has a body support condition in which the moveable body support structure is contactingly supporting said person (11), the moveable body support structure being attached to the main frame (10) in a translationally and/or rotationally moveable manner relative to the main frame such that, during said walking of said person in said body support condition, the moveable body support structure at least partly follows said body reference part (12) in said relative translational and/or rotational movement between said body reference part and said frame reference part (2, 3).
Walk training apparatus according to claim 2, wherein, as considered in said reference condition, said moveable body support structure comprises a body weight carrier (14), which body weight carrier has a body weight support condition in which the body weight carrier is carrying body weight of said person (11), the body weight carrier being attached to the main frame (10) in a moveable manner relative to the main frame such that, during said walking of said person in said body weight support condition, the body weight carrier at least partly follows said body reference part (12) in said relative translational and/or rotational movement between said body reference part and said frame reference part (2, 3).
Walk training apparatus according to claim 3, wherein, as considered in said reference condition, said moveable body support structure (14-22) further comprises a constant force mechanism (21), and wherein said moveable manner in which the body weight carrier (14) is attached to the main frame (10) comprises a vertical moveability component in that the body weight carrier is attached to the main frame in at least a vertically moveable manner relative to the main frame such that, during said walking of said person (11) in said body weight support condition, the body weight carrier at least partly follows said body reference part (12) in its relative vertical movement between said body reference part and said frame reference part (2, 3), and wherein said vertically moveable manner in which the body weight carrier is attached to the main frame is realized by means of said constant force mechanism (21) which, during said walking of said person in said body weight support condition, provides an upwardly directed supporting force which is constant throughout a vertical movement range of the vertical movement component of the body weight carrier relative to the main frame.
Walk training apparatus according to any one of claims 2-4, wherein, as considered in said reference condition, said moveable body support structure (14-22) comprises elastic structure (19, 20) for realizing, in an elastic manner, said translationally and/or rotationally moveable manner in which said moveable body support structure is attached to the main frame (10).
Walk training apparatus according to claim 5, wherein, as considered in said reference condition, the at least one calculator (7) is configured, arranged and effective to calculate said at least one drive control parameter based on a combination of (i) relative translational and/or rotational movement, detected by said at least one sensor (6), and (ii) elastic translational and/or torsional stiffness of said elastic structure (19, 20).
Walk training apparatus according to any one of the preceding claims, wherein the apparatus (1), as considered in said reference condition, further comprises at least one adjustor (9), which is communicatively connected to said at least one calculator (7) and which is configured, arranged and effective (i) to receive an adjustment instruction, and (ii) to adjust said at least one calculator, based on said adjustment instruction, into different operation modes of the walk training apparatus, by adjusting the way in which said at least one drive control parameter is calculated based on said detection results obtained by said at least one sensor.
Walk training apparatus according to claim 7, wherein, as considered in said reference condition, said different operation modes of the walk training apparatus (1), obtainable by said adjusting of said at least one calculator (7), comprise:
- a first operation mode, during which first operation mode said at least one drive control parameter is calculated to control said at least one drive unit (5) to drive the rolling assembly (4) such that the main frame (10) performs rolling movements over said floor according to a predetermined rolling trajectory, thus imposing a correspondingly predetermined walking trajectory to said person (11); and

- a second operation mode, during which second operation mode said at least one drive control parameter is calculated to control said at least one drive unit (5) to drive the rolling assembly (4) in such manner that a voluntary walking trajectory performed by said person (11) over said floor imposes an obedient rolling trajectory of the main frame (10), wherein said obedient rolling trajectory of the main frame relative to said floor, in terms of shape and position dependent speed, is substantially the same as the vertical projection onto said horizontal floor of the trajectory of said body reference part (12) relative to said floor caused by said voluntary walking trajectory performed by said person.
Walk training apparatus according to claim 8, wherein, as considered in said reference condition, said different operation modes of the walk training apparatus (1), obtainable by said adjusting of said at least one calculator (7), further comprise:
- at least one third operation mode, during which third operation mode said at least one drive control parameter is calculated to control said at least one drive unit (5) to drive the rolling assembly (4) such that the main frame (10) performs rolling movements over said floor according to a part of a predetermined rolling trajectory as defined for said first operation mode, thus only partly imposing a correspondingly predetermined walking trajectory as defined for said first operation mode to said person (11), while allowing said person to partly perform a voluntary walking trajectory as defined for said second operation mode, thus only partly imposing said obedient rolling trajectory as defined for said second operation mode.
Walk training apparatus according to any one of the preceding claims, wherein the apparatus (1), as considered in said reference condition, further comprises a leg actuation mechanism (30), which leg actuation mechanism has a leg actuation condition in which the leg actuation mechanism is being controlled to supportingly guide the legs of said person (11) in performing walking movements by said person.
Walk training apparatus according to claim 10, wherein, as considered in said reference condition, said at least one calculator (7) is configured, arranged and effective to calculate, based on detection results obtained by said at least one sensor (6), at least one leg actuation control parameter for controlling said leg actuation mechanism (30) to realize said supportingly guiding the legs of said person (11), and wherein said at least one controller (8) is configured, arranged and effective to control said leg actuation mechanism based on said at least one leg actuation control parameter.
Walk training apparatus according to any one of the preceding claims, wherein the apparatus (1) is dimensioned to be used when said person (11) is a person at the age of less than two and a half years old, and/or, in other words, when said person is a toddler or baby at a natural learning-to-walk age.
Non-therapeutic use of a walk training apparatus (1) according to claim 12, for training the walking of a person (11) at the age of less than two and a half years old, and/or, in other words, for training the walking of a toddler or baby at a natural learning-to-walk age.