NL2016553B1

NL2016553B1 - Treadmill for rehabilitation purposes.

Info

Publication number: NL2016553B1
Application number: NL2016553A
Authority: NL
Inventors: Martens Peter
Original assignee: Forcelink B V
Priority date: 2016-04-05
Filing date: 2016-04-05
Publication date: 2017-10-17
Also published as: WO2017174481A1

Abstract

A treadmill for rehabilitation purposes, comprising: a substantially horizontal support plate and an endless running belt stretched between two cylindrical rotatable rollers, wherein said treadmill is provided with actuators arranged to cause said two rollers with said belt to move laterally relative to said support plate. Furthermore said support plate is mounted on first vertical supports being arranged to rest on a base surface, and said rollers are mounted on second vertical supports arranged to rest on said base surface, wherein said second vertical supports are separate from said first vertical supports. Sensors are arranged to determine local forces between said support plate and said base surface.

Description

Treadmill for rehabilitation purposes

The invention relates to a treadmill for rehabilitation purposes, comprising a substantially horizontal support plate having a front edge, a rear edge, and two lateral edges, seen in the treadmill’s walking direction, said support being arranged to rest on a base surface; and an endless running belt extending around said support plate, and stretched between two cylindrical rotatable rollers being arranged to rest on said base surface, one of said rollers extending at and parallel to the front edge of said support plate and the other one of said rollers extending at and parallel to the rear edge of said support plate, such that the top side of said belt rests on the top surface of said support plate. In the preferred embodiment said treadmill comprises a base arranged to be placed on a floor, the top surface of said base forming said base surface.

Such treadmills are disclosed in USA patent publication US 8,315,823 and European patent publication EP 2 435 140. A person’s ability to maintain body position and attitude, whether engaged in a relatively stationary activity such as standing or in a dynamic activity such as walking or running, is dependent on the person’s balance control. Anticipatory postural adjustments are usually performed in periods of time between about 150 to 200 milliseconds (ms). Unanticipated compensatory postural adjustments occur in response to, and to recover from, unanticipated postural challenges. For example, slipping on a wet floor, a sudden braking of a bus, or catching ones foot on a curbstone, are typically unanticipated postural challenges that elicit compensatory balance control to provide compensatory postural adjustments in order to prevent falling. Compensatory postural adjustments are typically faster than anticipatory postural adjustments and are usually performed in periods of time less than about 100 ms. Anticipated balance control, and/or compensatory balance control, often degrades with age and/or injury to the nervous and/or muscular system, which can result in injuries.

There is a need for a system that provides small, controlled and unpredictable perturbations during treadmill walking, which allows training compensatory postural responses during walking, which can improve compensatory postural responses. Known systems comprise a treadmill having a runway surface, on which the person stands, walks, or runs, which is controllable to produce measured displacements of the runway that challenge the person's posture and elicit the person's posture control to prevent losing balance and possibly falling.

It is an aim of the invention to provide a such a treadmill system for rehabilitation purposes which is highly accurate and/or responsive. With the preferred embodiment of the invention precise disturbances of the walking environment of a person using the treadmill for rehabilitation purposes can be induced and the response in the (forces of) movements of the person can be measured accurately, which response can for instance be used to instantly influence the disturbances in a feed back loop.

International patent publication WO 2010/136924 shows a treadmill wherein a frame, on which the rollers with the belt and the support plate are mounted, can be moved laterally relative to the base surface by an actuator. According to a first aspect of the invention however, the treadmill is provided with actuators arranged to cause said two rollers with said belt to move laterally relative to said support plate. This aspect of the invention aims at a highly responsive system, wherein fast as well as slow, and small as well as large, displacements of the walking surface of a person using the treadmill are possible.

In the treadmill of WO 2010/136924 a piezoelectric sensor determines the forces between the belt and the support plate, caused by the feet of the person using the treadmill. US 8,315,823 shows a treadmill wherein sensors determine the forces between a frame on which the rollers with the belt and the support plate are mounted and the base surface. However, according to a second aspect of the invention (wherein the feature that said treadmill is provided with actuators arranged to cause said two rollers with said belt to move laterally relative to said support plate is optional) the support plate is mounted on first vertical supports near its lateral edges, said vertical supports being arranged to rest on the base surface, and the rollers are mounted on second vertical supports arranged to rest on said base surface, wherein said second vertical supports are separate from said first vertical supports, and said first vertical supports of said support plate (being separate from said second vertical supports of said rollers) comprise support plate sensors arranged to determine local forces between said support plate and said base surface. Said sensors are connected to said processing means, and said processing means being further arranged to process said determined local forces. Said support plate sensors are preferably located at at least 3 different locations near the circumferential edge of said support plate. Preferably at least 3 of said support plate sensors are arranged to determine at least a vertical component of said forces at said at least 3 different locations. This aspect of the invention aims at an accurate determination of forces and/or moments of force which occur in the interaction between a person and the treadmill, wherein the natural frequency of the system is as high as possible. EP 0 394 146 shows treadmill wherein the support plate is mounted on first vertical supports near its lateral edges, said vertical supports being arranged to rest on the base surface, and the rollers are mounted on second vertical supports arranged to rest on said base surface, wherein said second vertical supports are separate from said first vertical supports. EP 0 394 146 does however not show sensors arranged to determine local forces between the support plate and the base surface.

Preferably said rollers are attached to a frame extending at least parallel to and near the front and rear edges of said support plate, said second vertical supports being attached to and extending downward from said frame. Preferably said rollers are movably attached to said frame such that the rollers can slide in the lateral direction.

In the preferred embodiment said treadmill is provided with a control unit, said control unit comprising processing means arranged to process signals from a motion capture system connected to it, said motion capture system being arranged to capture motion data of a person walking on said treadmill. Said motion capture system may be mounted on said treadmill. Preferably said processing means are arranged to selectively cause said actuators to laterally move said two rollers with said belt in response to said processed signals.

Said treadmill is preferably provided with a motor coupled to at least one of said rollers, and arranged to selectively rotate said at least one roller forward and/or backward.

Said treadmill is preferably arranged such that said actuators are able to cause said two rollers with said belt to be moved laterally relative to said support plate even while said rollers with said running belt are not rotating.

Preferably said processing means are arranged to set the rotation speed and/or rotation direction of said at least one roller. Preferably said processing means are arranged to set the rotation speed and/or rotation direction of said at least one roller in response to said processed signals.

Preferably the treadmill is furthermore arranged to determine also horizontal forces. In that case preferably both the support plate and the roller supports are provided with sensors, measuring all 6 degrees of freedom, at at least 3 locations (measuring both negative and positive forces in each direction). Said directions do not necessarily need to coincide with the vertical axis or the two horizontal axes. To that end preferably at least 3 of said support plate sensors are arranged to determine at least a horizontal component of said forces in at least 3 different horizontal directions, and said second vertical supports of said rollers preferably also comprise roller sensors arranged to determine local forces between said rollers and said base surface, said sensors being connected to said processing means, said processing means being further arranged to process said determined local forces, wherein preferably at least 3 of said roller sensors are arranged to determine at least a horizontal component of said forces in at least 3 different horizontal directions.

The invention will now be elucidated by means of a preferred embodiment as shown in the figures, wherein:

Figure 1 is a perspective view of a treadmill in accordance with the invention; and Figure 2 is a top view of the treadmill of figure 1.

In the figures, a treadmill is shown, which can for instance be used as shown and described for the treadmill as indicated by the reference numeral 20 in the figures of WO 2010/136924. To that end, WO 2010/136924 is incorporated by reference here.

The treadmill 1 of the current invention comprises a base 2, on which a horizontally extending rectangular support plate 3 is mounted. The support plate 3 is mounted on vertical legs 4, extending downward form each corner, said legs 4 resting on the horizontal top surface of the base 2. The legs 4 of the support plate 3 each consist of two telescopic parts (a top part 4a and bottom part 4b) and a sensor is provided between the two telescopic parts, arranged to continuously determine the vertical force on said corners of the support plate 3. Furthermore the legs 4 each comprise sensors between the two telescopic parts, arranged to continuously determine the horizontal forces in two perpendicular directions (i.e. the belt’s running direction and the lateral direction) between said two telescopic parts at the corners of the support plate 3. It will be understood that the system does not necessarily need all of these sensors to determine all the forces in all directions, a minimum of 3 sensors at 3 different locations of the support plate 3 measuring in 3 different horizontal directions, and 3 sensors at 3 different locations of the support plate 3 measuring in the vertical direction, could achieve this.

An endless movable running belt 5 extends around the support plate 3, such that the bottom surface of the top side of the belt 5 rests on and moves over the top surface of the support plate 3. The running belt 5 is stretched between two rotatable cylindrical rollers 6, of which one roller is driven by an electric motor 7. The ends of the rollers 6 are rotatably mounted in bearings 8.

The bearings 8 with the rollers 6 and the running belt 5are mounted to a rectangular horizontally extending frame 9. The frame 9 is mounted on vertical legs 10, extending downward form each comer, said legs 10 resting on the horizontal top surface of the base 2. The legs 10 of frame 9 each consist of two telescopic parts (a top part 10a and a bottom part 10b) and a sensor is provided between the two telescopic parts, arranged to continuously determine the vertical force on said comers of the frame 9. Also here, 3 sensors at 3 different locations of the frame 9 measuring in the vertical direction, could be sufficient to determine the forces in all directions.

In order to allow lateral movement of the rollers 6 with the running belt 5 relative to the support plate 3, the bearings 8 at both sides of the belt 5 are slidingly mounted to the frame 9, and actuators are provided at both ends for causing the belt 5 to move laterally relative to the support plate 3. In this example the front and rear beams of the frame 9 are provided with a plain rod 12 and a threaded rotatable drive rod 13, extending parallel to each other and to the respective front and rear beams of the frame, and the bearings 8 are each provided with corresponding holes. One hole on each bearing slidingly extends around the plain rod 12, and one bearing on each end of the belt is provided with a second hole which is threaded in correspondence with the threaded drive rod 13, in order to be driven thereby. Motors 11 drive the drive rods 13, which together form the actuators in this example. As will be obvious to the skilled person, other means of moving the rollers 6 laterally are possible, such as, but not limited to, a toothed belt and gear wheel, a cranckshaft, or a pneumatic/hydraulic piston.

The sensors in the legs 4 and the driving motors 7, 11 are connected to processing and control means, such as a computer with input and display means as shown in WO 2010/136924. In the preferred embodiment these processing and control means are connected to a motion capture system.

The treadmill system according to the invention thus provides highly responsive system, wherein balance disturbances in two directions can be induced either when walking or at standstill, with an accurate determination of all the relevant forces with a high natural frequency of the system, wherein said determination is not influenced by the mass and vibrations of the motors and rolls.

The invention has thus been described by means of a preferred embodiment. It is to be understood, however, that this disclosure is merely illustrative. Various details of the structure and function were presented, but changes made therein, to the full extent extended by the general meaning of the terms in which the appended claims are expressed, are understood to be within the principle of the present invention. The description and drawings shall be used to interpret the claims. The claims should not be interpreted as meaning that the extent of the protection sought is to be understood as that defined by the strict, literal meaning of the wording used in the claims, the description and drawings being employed only for the purpose of resolving an ambiguity found in the claims. For the purpose of determining the extent of protection sought by the claims, due account shall be taken of any element which is equivalent to an element specified therein.

Claims

A treadmill for rehabilitation purposes, comprising: a substantially horizontal carrier plate with a front edge, a rear edge and two side edges, viewed in the running direction treadmill, the carrier plate being adapted to rest on a base surface; and an endless conveyor belt that extends around the carrier plate and is tensioned between two cylindrical rotatable rollers and adapted to rest on the base surface, one of the rollers extending at and parallel to the front edge of the carrier plate and the others of the rollers extend at and parallel to the rear edge of the carrier plate such that the top of the belt rests on the upper surface of the carrier plate; characterized in that the treadmill is provided with actuators adapted to cause the two rollers with the belt to move sideways relative to the carrier plate.

The treadmill of claim 1, wherein the rollers are attached to a frame that extends at least parallel to and near the front and rear edges of the carrier plate, the second vertical supports being attached to and extending downwardly from the frame.

A treadmill according to claim 1 or 2, wherein the rollers are movably attached to the frame such that the rollers can slide in the sideways direction.

4. Treadmill as claimed in claim 1, 2 or 3, wherein the treadmill is provided with a control unit, which control unit comprises processing means which are adapted to process signals from an associated motion capture system, wherein the motion capture system is arranged for movement data of a person which runs on the treadmill, and wherein the processing means are adapted to cause the actuators to move the two rollers laterally with the belt in response to the processed signals.

5. Treadmill according to one of the preceding claims, wherein the treadmill is provided with a motor which is coupled to at least one of the rollers and which is adapted to selectively rotate the at least one roll forwards and / or backwards.

6. Treadmill according to any of the preceding claims, wherein the treadmill is arranged such that said actuators can cause the two rollers with the belt to move laterally relative to the carrier plate even if the rollers with the conveyor belt do not rotate.

7. Treadmill according to one of the preceding claims, wherein the processing means are adapted to adjust the speed and / or the direction of rotation of the at least one roller.

A treadmill according to any one of the preceding claims, wherein the processing means are adapted to adjust the speed and / or direction of rotation of the at least one roll in response to the processed signals.

9. Treadmill according to one of the preceding claims, wherein the feature of claim 1 that the treadmill is provided with actuators adapted to cause the two rollers to move sideways with respect to the carrier plate is optional, the carrier plate being adjacent its side edges are attached to first vertical supports, the vertical supports being adapted to rest on the base surface;

The treadmill of claim 9, wherein the rollers are mounted on second vertical supports adapted to rest on the base surface, the second vertical supports being separated from the first vertical supports.

11. Treadmill as claimed in claim 9 or 10, wherein the first vertical supports of the carrier plate comprise carrier position sensors which are adapted to determine local forces between the carrier plate and the base surface, wherein the sensors are connected to the processing means, and wherein the processing means are further arranged for processing the determined local forces.

The treadmill of claim 11, wherein the carrier location sensors are located at at least 3 different locations near the peripheral edge of the carrier plate, the carrier location sensors being adapted to determine at least one vertical component of the forces.

A treadmill according to claim 10 and optionally claim 11 or 12, wherein the second vertical supports of the rollers comprise roller sensors which are adapted to determine local forces between the rollers and the base surface, which sensors are connected to the processing means, the processing means further are designed to handle the specific local forces.

A treadmill according to claim 11 and optionally claim 12 or 13, wherein at least 3 of said carrier position sensors are adapted to determine at least one horizontal component of the forces in at least 3 different horizontal directions.

A treadmill according to claim 13 and optionally claim 14, wherein at least 3 of said roller sensors are adapted to determine at least one horizontal component of the forces in at least 3 different horizontal directions, and wherein at least 3 of the roller sensors are preferably arranged to determine at least one vertical component of the forces at at least 3 different locations.

A treadmill according to any one of the preceding claims, wherein the treadmill comprises a base adapted to be placed on a floor, the upper surface of the base forming said base surface.

The treadmill of claim 4 and optionally one of the preceding claims 5-16, wherein the motion capture system is mounted on the treadmill.