WO2021116721A1

WO2021116721A1 - Motion assistance device

Info

Publication number: WO2021116721A1
Application number: PCT/HU2019/050054
Authority: WO
Inventors: Bálint PÁLMAI
Original assignee: Palmai Balint
Priority date: 2019-12-11
Filing date: 2019-12-11
Publication date: 2021-06-17

Abstract

Motion assistance device (100) comprising i) a motor housing (1), the motor housing (1) contains motors (2), at least four disks (8) functionally connected to the motors (2), band flexing springs (28) for every disk (8) for keeping the band tense, and hip sensors (31) for every disk (8), a processor (11), a memory (12), at least one signal transfer device (26a), ii) a main frame (3) for mounting the motion assistance device (100) around the hip of the user (200), which contains a battery (6) and a battery docking unit (7), and the main frame (3) holds the motor housing (1); iii) a front force transmitting band (15) and a back force transmitting band (16) for running along the opposite sides of each leg of the user (200), and a supporting device (13) suitable for attaching it around the knee of the user (200), where the force transmitting bands (15, 16) connect via connection means (21, 22) the supporting device (13) with the disks (8) in the motor housing (1) at the respective sides of the user (200), characterized in that each supporting device (13) further comprises a knee sensor (23) and a signal transfer device (26b).

Description

Motion assistance device

Technical field of the invention

The object of the present invention relates to a motion assistance device for assisting people with walking, running, climbing stairs etc. The motion assistance device has a main frame fixedly tightened to the waist of the user, contains furthermore motor(s), a supporting device and force transmitting bands, and helps to move the thighs of the user by detecting the user's motion with at least a knee sensor and a hip sensor.

Background art

People with certain conditions, for example in old age, overweight people or even healthy people in exhausting situations like soldiers, firefighters or hikers with heavy equipment sometimes have problems with motion, especially in long distances, with height differences, or if the motion is needed for a longer time. Motion assistance devices (in other terms exosuites or exoskeletons) are devices that assist to moving people. In general, motion assistance devices are attached to certain parts (e.g. hip, legs) of the human body and provide additional force to certain joint(s) (e.g. the knees) to help the movement of said joint.

Some of the known motion assistance devices, like the ones described in WO2014109799A1, CN107259661A, US2010144490A1 or W02018122106A1 patent documents are heavy, contact with the whole body, therefore they are inconvenient to use. These kinds of motion assistance devices are usually referred to as exoskeletons . Less complicated motion assistance devices usually comprise a belt, a few motors, controller(s), sensors and a supporting part attached to the leg(s). The motion assistance device disclosed in the EP3132783A2 published patent application includes a fixing module to provide a torque to assist motion of the user, a supporting module connected to a driving module to support the rear portion of the thigh of the user, and a controller configured to control the driving module to provide a torque to maintain a close contact between the supporting module and the leg of the user while the user is not walking. The problem with this device is the configuration of the supporting module that supports only the rear portion of the thigh of the user. Namely, this configuration is not efficient, because the device cannot help to lower the thigh, just lifts it. Consequently, the motion is not fluent as the device helps only one way of the movement. Another problem is that the device keeps pressure on the thigh to maintain the close contact between the thigh and the supporting plate when the user is standing, which pressure is quite inconvenient. Furthermore, the measurement of the movement is dependent of the device, because one set of the sensors determines the leg rotation from the movement of the thighs, which thigh movement, however, is assisted by the device itself. Therefore, it is possible that the user wants to lower his/her thigh, while the device still forces to lift it up.

Another motion assistance device is described in the DE102016208524A1 published patent application. The solution described here provides a walk assistance device including a main frame configured to be carried by the user, a drive unit attached to the main frame, a pair of power transmission members pivotally mounted on the main frame so as to be rotatable around the respective hip joint of the user and for transmitting an assisting force supplied by the drive unit to the thigh portions of the user, and a control unit for controlling operation of the drive unit. The control unit comprises: a differential angle calculating unit for calculating a differential angle between angular positions of the femoral parts of the user around the respective hip joint of the user; a differential angle phase calculation unit for calculating a differential angle phase according to the differential angle; and an assist force calculation unit for calculating an assist force for application to the user according to the differential angle phase. A drawback of this device is that the power transmission members are made from rigid material, so they prevent the leg motion to the abduction, adduction direction and are inconvenient to wear. Another problem is that the device measures the angles from the femoral portion of the user, which femoral portion movement is assisted with the device, so the measurement is not independent from the device itself. When the user changes his/her motion he/she will work against the device itself.

Another solution is a motion assistance device disclosed in WO2013145769A1 published international patent application, which has a simple structure and is lightweight and the user can easily put it on and take it off. The structure of the device is capable of safely supporting the ambulation without impeding the user's autonomous fall-preventing movement even in the case of a disturbance such as an external force on the user in the transverse direction. The motion assistance device is equipped with a pair of left and right assistance members provided with driving sources which exert a tensile force on flexible supplementary force-transmitting sections, and a control means for controlling the respective driving source of each assistance member according to changes in the joint angles of the user's hip joints. Disadvantages of the solution are its limited assistance in walking and it only assists in lifting the leg, because the device is attached to the front side of the thigh. Another problem is that the device measures the femur joint angle in the relation with the hip joint, so the measurement is dependent from the assisted motion and when the user changes his/her motion he/she will work against the device itself.

Another motion assistance device described in the US2018092794A1 published patent application includes an upper- body belt attached to the upper body of the user, first and second belts attached to the knees, a first wire coupling the upper-body belt to the first belt, a second wire crossing the first wire, a third wire coupling the upper-body belt to the second belt, a fourth wire crossing the third wire, and a motor coupled to one end of each of the first to fourth wires. When assisting users with walking, tensions equal to a first threshold value or greater are applied to one of the first and second wires and one of the third and fourth wires by the motor at different times. When detecting slacking of the upper-body belt, tensions equal to the first threshold value or greater are simultaneously applied to one of the first and second wires and one of the third and fourth wires by the motor. The device is inefficient in measuring force, angle or position with slack and movable belt. Secondly, because of the device detects the slacking of the wire and corrects it, in the rest position the trigger value for tense wire unnecessarily loads the joints.

The aim of the present invention is to provide a motion assistance device that is free of the disadvantages of the solutions according to the state of the art. In other words the solution of the present invention shall be able to provide assistance for motion of the lower limbs without restricting their moves with working against the movement, i.e. because of the actuation dependent control of the device (the device's forced actuation works against the user's movement, when the direction of the movement changes) or because of the device loads the joints in rest position to keep contact with the legs or keep the supporting bands of the device tight.

The present invention is based on the recognition that from the values of the angles and dynamic parameters of the knee together with the values of the angles and dynamic parameters of the hip, the user's voluntary movement is precisely recognizable and obtaining these values does not work against the movement of the user and thereby will not load the joints and muscles in rest position or the device would not work against the user, when he or she changes the direction of the movement.

The task was solved in the sense of the invention with the motion assistance device according to claim 1.

Individual preferable embodiments of the invention are specified in the dependent claims.

Brief description of the drawings

The details of the invention are presented in connection with embodiments, with the help of drawings. In the appended drawings: Figure 1 shows the motion assistance device of the present invention mounted on a user in side view.

Figure 2a and 2b show the motion assistance device of the present invention mounted on a user in front view and back view.

Figure 3 shows a closer side view of the motion assistance device of the present invention mounted onto the hip of a user.

Figure 4 shows a preferred embodiment of the motor housing of the motion assistance device of the present invention in top view.

Figure 5 shows an alternative embodiment of the motor housing of the motion assistance device of the present invention in top view.

Figures 6a and 6b show the supporting device of the motion assistance device of the present invention arranged around of the knee of the user, when the knee is in resting position (Fig. 6a) and when the knee is in bent position (Fig. 6b). Figures 7a and 7b show the supporting device of the motion assistance device of the present invention in side view (Fig. 7a) and in front view (Fig. 7b).

Figure 8 shows the angles of a human lower limb.

Figure 9 shows the steps of a walking human.

Figure 10 shows the steps of a running human.

Figure 11 shows the steps of a human who climbing stairs. Figure 12 shows the functions of the hip angles and knee angles in a motion cycle during sprint, run and walk.

As shown in Fig. 1, the motion assistance device 100 contains a motor housing 1, a main frame 3 and a supporting device 13. The main frame 3 is configured to be attached to the waist of the user 200 and the motor housing 1 is connected to this main frame 3. The supporting device 13 is configured to be attached to one of the knees of the user 200 and is linked to disks located within the motor housing 1 with a rear force transmitting band 15 and a front force transmitting band 16. The motion assistance device 100 according to the present invention is configured to assist the motion of two legs of the user 200 therefore another supporting device 13 is similarly attached to the other knee with other bands 15 and 16 and linked to other disks. However, for the sake of clarity, Fig. 1 depicts a side view, where the configuration around one knee is visible.

The main frame 3 is formed by a belt with a beltbucket 5 as shown in Fig. 2a. Alternatively, if the motion assistance device 100 is built into a piece of clothing (not shown), then the waist region of the piece of clothing is forming the main frame 3. The main frame 3 fixedly tightens to the body of the user 200, conveniently right above the hip bone. The motor housing 1 is attached to the main frame 3. A supporting device 13 is attached to each knee of the user 200. The supporting device 13 is connected to disks (not shown in Figs. 2) within the motor housing 1 by force transmitting bands 15 and 16.

Fig. 2b shows the motion assistance device of the present invention mounted on the user 200 in back view.

Fig. 3 shows a closer side view of the motion assistance device 100 mounted onto the main frame 3 on the hip of the user 200. The motor housing 1 houses four motors 2 in total (motors 2f and 2b are shown in Fig. 3), two at each side of the user 200. Fig. 3 shows a schematic side view, i.e. the right-hand side of the user 200. The motor 2 in front of the user is the front motor 2f, the motor 2 behind the user is the back motor 2b. The front motor 2f rotates a front disk 8f and the back motor 2b rotates a back disk 8b. By rotating the front disk 8f the front force transmitting band 16 is coiled up. By rotating the back disk 8b by the back motor 2b, the rear force transmitting band 15 is coiled up. The movement of the leg of the user 200 coils down the force transmitting bands 15 and 16 without the work of the motors 2. The transmitting bands 15 and 16 are guided towards the knee region by anti-friction casters 4. In order to have the force transmitting bands 15 and 16 tightened, the depicted configuration includes also a band flexing spring 28 and a freewheel 29 at each disk 8f and 8b. The motion assistance device 100 is equipped with a first signal transfer device 26a for the signal transfer between the processor (not shown in Fig. 3) and the supporting devices 13. Preferable, the first signal transfer device 26a is wireless, but it is possible to use wires for the signal transfer too, which wires are are built in or on the transmitting bands 15 and 16 to connect the supporting devices 13 with the processor.

The purpose of the band flexing spring 28 is not to let the transmitting bands 15 and 16 become slack. It is important to coil up the transmitting bands 15 and 16 in inactive mode either, i.e. when the motors 2 do not work.

The purpose of the freewheel 29 is to let the transmitting bands 15 and 16 to be coiled up to the disks 8 faster than the motor 2 would be capable in itself to coil them, because it is possible that the user motion is faster as the motion assistance device 100 assist the movement by the motor 2 coil up the transmitting bands 15 and 16. This scenario can happen when the user 200 trip over or change his/her motion type. Fig. 4 shows a preferred embodiment of the motor housing 1 in top view, without depicting the user 200. It is shown schematically here that the motor housing 1 further houses different controller devices, like a processor 11, memories 12 and a first signal transfer device 26a, the supporting device 13 houses the second signal transfer device 26b (not shown in Fig. 4.). Based on the signals from the supporting devices 13 at the knee regions (not depicted in Fig. 4) and from a hip sensor 31 (not depicted in this figure) for every disks 8, these controller devices 11, 12, 26a and 26b control the rotations of the motors 2 and thereby control the movements of the rear force transmitting bands 15 and front force transmitting bands 16. In order to provide the motors 2 and the controller devices 11, 12 and 26a with the necessary electric energy, a battery 6 is provided in the motor housing 1. The battery 6 is attached to the motion assistance device 100 through a battery docking unit 7.

It can be seen in Fig. 4 that the main frame 3 has a circular or oval shape in order to fit the motion assistance device 100 to the user 200 (user 200 not shown in this figure). The beltbucket 5 helps tightening the main frame 3 to the user's hip with the necessary strength. The position of the other parts of the motion assistance device 100 is also shown in this schematic picture, namely the motors 2 connected to the disks 8, which have the rear force transmitting bands 15 and front force transmitting bands 16 coiled partly on themselves.

These force transmitting bands 15 and 16 run through the anti-friction casters 4 towards the supporting devices 13 (not shown in Fig. 4). The purpose of these anti-friction casters 4 is to make the wearability of the motion assistance device 100 more convenient and efficient. According to a preferred embodiment (not shown in Fig. 4) it is possible to telescopically pull out these anti-friction casters 4 distant from the motor housing 1, thereby avoiding the transmitting bands 15 and 16 touching the lower end of the thigh. Because of the distant position of the anti-friction casters 4 it is possible to optimize the direction of the force transmitted to the thigh by the transmitting bands 15 and 16. For example, in case of a climbing motion it is necessary to exert bigger force, which is possible with greater distance between the anti-friction casters 4 and the motor housing 1. This changeability provides the motion assistance device 100 efficiency in different motions like walking, running, climbing, biking or similar type of motions.

Fig. 5 shows an alternative embodiment of the motor housing 1 of the motion assistance device 100. In case of this embodiment the motor housing 1 houses two motors 2, one at each side. Each motor 2 rotates two disks 8, one back disk 8b for the rear force transmitting band 15 and the front disk 8f for the front force transmitting band 16. Compared to the previous embodiment the motors 2 are bidirectional here and a clutch (not shown in the figures) is applied to the disks 8 as it is necessary to detach one of the disks 8 from the motor 2 when it rotates the other disk 8 attached to that motor 2. Application of a clutch in this embodiment is important because two disks 8 for one motor 2 cannot be placed in the rotation point of the hip joint, that is why the length of the rotated parts of the transmitting bands 15 and 16 are not equivalent in the front and rear side. We do not exclude the option that other embodiments use clutch either, like the first one described earlier. This second embodiment utilizes the fact according to which when the front force transmitting band 16 at one side coils down passively from the detached front disk 8f, the same time the rear force transmitting band 15 coils up to the back disk 8b by their common motor 2, and vice versa. The other parts (like e.g. the anti-friction casters 4, the controller devices 11, 12 and 26a the battery 6 and its docking unit 7, the main frame 3 and the beltbucket 5, the band flexing spring 28 and the freewheel 29) of this embodiment have the same function as in the other embodiment.

The supporting device 13 is arranged around the knee of the user 200, as shown in Figs. 6a and 6b. The supporting device 13 includes a front part connecting means 21 on its front part for connecting the front force transmitting band 16 to the supporting device 13. Similarly, the supporting device 13 includes a rear part connecting means 22 on its rear part for connecting the rear force transmitting band 15 to the supporting device 13. The supporting device 13 has a cuff shape for the leg's knee region with an opening to the knee. The purpose of the opening 30 is to let the knee freely bend. The upper section 19 of the supporting device 13 is connected to the bottom section 20 of the supporting device 13 with a stretch detecting device 24. The stretch detecting device 24 contains a knee sensor 23 functioning as a stretching detector. Fig. 6a shows the knee of the user 200 with the supporting device 13 mounted on it when the knee is in its resting position, while Fig. 6b shows the same arrangement when the knee is in its bent position. The knee sensor 23 is shown as being longer in Fig. 6b compared to Fig. 6a due to its stretched state on the bent knee.

Figs. 7a and 7b show the supporting device 13 in more detailed view, where Fig. 7a shows the side view and Fig. 7b shows the front view of the supporting device 13. For the sake of clarity, the knee of the user 200 is not depicted in these figures.

It can be seen in Fig. 7a that the rear force transmitting band 15 and the front force transmitting band 16 are connecting to the supporting device 13 through the rear part connecting means 22 and the front part connecting means 21, respectively. The front part connecting means 21 connects the front force transmitting band 16 to a force transmitting knee band 18. The force transmitting knee band 18 is attached by a stitching 25 to the supporting device 13 behind the opening 30. The stitching 25 is further attached to the upper section 19 of the supporting device 13 and to the bottom section 20 of the supporting device 13 by connecting means 27 The purpose of these connecting means 27 is to help the stretch detecting device 24 moving with the front section 19 and bottom section 20 of the supporting device 13 without too much effort because of the strong connections with the stitching 25 or the back part 36 of the supporting device 13. The stitching 25 and connecting means 27 are optional, they are just to help the precise measurement of the knee angle by the knee sensor 23. The upper section 19 of the supporting device 13 is connected to the bottom section 20 of the supporting device 13 with a stretch detecting device 24. The upper section 19 and bottom section 20 forms an opening 30 between them. The stretch detecting device 24 contains a knee sensor 23.

Fig. 7b is showing the supporting device 13 in front view. The supporting device 13 has a second signal transfer device 26b that transmits the value of the level of the stretching of the knee to the processor 11 located in the motor housing 1. The level of stretching is measured by the knee sensor 23 and the measured values are transferred from the knee sensor 23 to the second signal transfer device 26b via electronic cables 35. The stretch detecting device 24 connects the upper section 19 and bottom section 20 and holds the knee sensor 23. The stretch detecting device 24 has two parts. The first part 34 is the one connected to the upper section 19 and holding the knee sensor 23, which first part 34 is elastic. The second part 33 is the one connected to the lower section 20, which second part 33 is non-elastic. The second part 33 of the stretch detecting device 24 is non elastic, because of the electric wires, which link the knee sensor 23 with the second signal transfer device 26b. The second signal transfer device 26b mounted on the lower section 20 has a battery 32 for providing electric energy source.

The motion assistance device 100 assists the movements of the thighs of the user 200. For example, in case of a walking movement, as the user 200 lifts his/her right thigh and the right knee is bending, the motor 2f coils up the front force transmitting band 16 of the right leg to the front disk 8f. At the same time on the other side, the other side's motor 2b coils up the rear force transmitting band 15 of the left leg from the back disk 8b. The opposite transmitting bands 15 and 16 are coiled down passively, without the help of motors.

To detect the movement of the user 200 the supporting device 13 contains the knee sensor 23 on the stretch detecting device 24, which knee sensor 23 is stretching as the knee of the user 200 bends. From the level of the stretching and the elapsed time during the stretching several parameters of the movement can be calculated by the processor 11, like the actual angle between the thigh and the shin (i.e. knee angle) of the user 200 and the dynamic parameters of this movement, like angular velocity, angle of rotation or angular acceleration. For a precise measurement the stretch detecting device 24 needs to behave independently from the rear force transmitting band 15, the front force transmitting band 16 and the motors 2. For this purpose the front force transmitting band 16 needs to be attached to the force transmitting knee band 18, which force transmitting knee band 18 is attached to the supporting device 13 behind the opening 30 as seen in Fig. 7a. Due to this configuration when the front force transmitting band 16 lifts the thigh, the force would not stretch the opening 30 of the supporting device 13 and would not interfere with the behaviour of the knee sensor 23.

Fig. 8. shows the angles of the human lower limb (hip angle, knee angle and ankle angle).

It's necessary to detect the hip movement too for precise motion measurement. As shown in Fig. 5. hip sensors 31 are used for detecting the parameters of the disks 8, i.e. its rotary motion and angular position. From this information the angle between the thigh and the hip (hip angle), the movement direction of the thigh, the hip joint angular velocity, angle of rotation and angular acceleration can be calculated by the processor 11. The disk 8 is rotating around itself and as the transmitting bands 15 and 16 are always tense, from the angular position of the rotated disk 8 the length of the released or coiled transmitting bands 15 and 16 can be calculated by the processor 11.

A preferred embodiment for the hip sensor 31 is an optical absolute encoder, where the disk 8 contains holes at specific locations. A light source (e.g. a laser light) is applied (not depicted in Fig. 5.) to the disk 8 and on the other side of the disk 8 a light detector is arranged. If the light beam transmits through said holes, the detector will detect the light. If there is no hole in the path of the light beam, the detector will not detect light. The rotary motion of the disk 8 and its direction can be calculated from the periodicity of the detected light beam. Other known absolute encoders can work too, which are capable to recognize the disk 8 position in any time.

According to a preferred embodiment, a gyroscope is used in the supporting device 13. The gyroscope is capable to measure the position of the knee in relation to the ground, thereby the movement of the thigh, which helps to determine the precise data measured by the hip sensors 31.

According to another preferred embodiment the hip sensor 31 can be replaced with a gyroscope in the supporting device 13.

The disks 8 coil and release the transmitting bands 15 and 16, when the user 200 moving. Anti-friction casters 4 can be applied in the motion assistance device 100 to decrease the friction, when the force transmitting bands 15 and 16 are moving. Elimination of the resistance of the motors 2 is useful, if their resistance significantly increases the necessary power for coiling the transmitting bands 15 and 16, when the motors 2 do not assist the motion. For this purpose, clutches are used, which clutches detach the disks 8 from the motors 2, thereby the motion of the user 200 can rotate the disks 8 freely.

The motion assistance device 100 has many possible working modes. For example, in its inactive mode the motors 2 and the sensors 23 and 31 are inactive and do not work, the motion assistance device 100 does not use the battery 6 and 32. If there are clutches in the motor housing 1, they detach the disks 8 from the motors 2 to decrease the system resistance, when the force transmitting bands 15 and 16 coil up or down. If the disks 8 are detached, then the band flexing spring 28 is the only means, which works against the movement of the user 200, and the anti-friction casters 4 decrease the friction which works against the force transmitting bands 15 and 16. The inactive mode is useful when assistance of the movement is not needed, however, the motion assistance device 100 will be needed later.

In the aggregator mode of the motion assistance device 100 the sensors 23 and 31 are inactive. As the user 200 moves, the movement of the legs actuates the force transmitting bands 15 and 16. As the force transmitting bands 15 and 16 drive the motors 2, they will function as generators, thereby electricity will be produced and stored in the battery 6. If the battery 6 is charged fully to avoid the overcharge the clutches detach the disks 8 from the motors 2. If the motion assistance device 100 do not contain clutches, it will switch to inactive mode (see above). The aggregator mode can be useful in cases where motion does not need assistance or even if a breaking effect is useful, i.e. in case of downhill motions.

In the teaching active mode, the motion assistance device 100 monitors the motion of the user 200 first and thereafter the motion assistance device 100 assists the motion when at least two or three motion cycles are repeated from the same motion type. In case the motion cycle is interrupted, switched to another type of motion or changed somehow, the motion assistance device 100 stops to assist the motion and switches to the teaching active mode. The teaching active mode is necessary, as the motion within a certain motion type (i.e. walking, running, hiking, etc.) is different from user to user, because every user has his/her own body type and motion cycle. During the teaching active mode, the motion assistance device 100 collects data of the certain user and creates, determines the best assistance algorithms for that certain user and if necessary, correct these schemes. So the motion assistance device 100 in teaching active mode creates algorithms for the different motion types based on repeated motion cycles of the user 200, and even correct the algorithms based on repeated motion cycles if it is necessary. The teaching active mode can be useful i.e. in case of jogging.

In the simple active mode, the sensors 23 and 31 work and the motion assistance device 100 helps the motion of the user 200 from the first motion cycle based on the calculations of the data from the sensors 23 and 31 by the processor 11. The memory 12 stores these data, the motion cycle patterns and the necessary steps of the algorithms for the steps of these motion cycles. In case the motion cycle is interrupted, switched to another type of motion or changed somehow, the motion assistance device 100 stops to assist the motion or switch other algorithm, when the user 200 switch his/her motion type. So the motion assistance device 100 in simple active mode uses the already saved algorithms for the different motion types in the first and do not correct them. These algorithms can be programmed before the first use of the motion assistance device or are created by teaching active mode of the motion assistance device 100. The simple active mode can be useful in cases where motion types are switched regularly .

According to a preferred embodiment (not depicted in the figures), another motor can be applied for assisting the Achilles tendon. The calves do about half of the work during the walking motion and even 30-40% at fast walking or running. One way to help the work of the calves is to assist the Achilles tendon at the moment when the heel of the user 200 is lifted off from the ground. A string attached to the heel and a motor in the motor housing 1 or in the thigh of the user 200 can pull up the heel of the user 200 in that moment when the heel of the user 200 is lifted off from the ground, similarly as the Achilles tendon works. Obviously, both heels have a string and the motor lifts up only the heel to be lifted up in a certain moment by pulling the related string. The string for example can be a Bowden cable.

The knee sensor 23 according to the present invention detects the change in the distance between the upper section 19 and bottom section 20 and the time needed for said change. According to a preferred embodiment the knee sensor 23 is a stretch detecting stamp. According to another preferred embodiment the knee sensor 23 is a two-part sensor above and below the knee (e.g. the two parts attached to the upper section 19 and bottom section 20, respectively), which sensors detect the distance from each other via e.g. an electromagnetic signal. According to another preferred embodiment the knee sensor 23 can be a flexible conductor material, where the resistance of the material changes depending on the level of the tilt. The connecting means 21 and 22 are configured so that the transmitting bands 15 and 16 are detachable from the supporting device 13. The purpose of the connecting means 21 and 22 is to help to put on or take off the motion assistance device 100. According to a preferred embodiment the connecting means 21 and 22 are rings with a small gap to connect the connecting means 21 and 22 to the transmitting bands 15 and 16 through a hole located in the end region of transmitting bands 15 and 16. After connecting the bands the rings are rotated away to avoid the disconnection of the connecting means 21 and 22 with the transmitting bands 15 and 16 like, i.e. they function like a keyholder ring. According to another preferred embodiment the connecting means 21 and 22 are clasps or buckles.

The connecting means 27 are configured so that the connections of the upper section 19 of the supporting device 13 and the bottom section 20 of the supporting device 13 to the back part 36 of the supporting device 13 do not limit their movement when the user 200 moves. This helps the precise measurement of the knee sensor 23. According to a preferred embodiment the connecting means 27 are hinges or clasps.

The signal transfer devices 26a and 26b practically wireless devices and these wireless signal transfer devices work with the widely accepted Bluetooth standard. The signal transfer devices 26a and 26b can be redeemed with wires. If wires connect the knee sensor 23 with the motor housing 1, then the connecting means 21 and 22 need to form a special buckle which can prevent the damage of the wires. For this purpose, the easiest way if the buckle is an electrical wire connector too and attach one electrical wire from the knee sensor 23 with another electrical wire going along the force transmitting bands 15 and 16 from the motor housing 1. Obviously, in this embodiment the battery 32 is unnecessary.

The processor 11 computes and calculates the type of the motion of the user based on the data of the knee sensors 23 and hip sensors 31 and execute the steps of the algorithm based on the motion.

The memory 12 stores the data from the knee sensors 23 and hip sensors 31 and other optional sensors like a gyroscope, and data about the unique motion of the user.

The anti-friction caster 4 is basically a caster, which can rotate freely around itself to help decreasing the effect of the friction which works against the transmitting bands 15 and 16.

The purpose of the disks 8 is to coil up and down the transmitting bands 15 and 16 to help the movement of the thighs of the user. According to a preferred embodiment the disk 8 has a circular shape. However, it is not necessarily a full round shape, it can be just a half-round or three-quarter round.

Transmitting bands 15 and 16 are preferably made from unstretchable and flexible material. If the transmitting bands 15 and 16 are made from stretchable material, then the transmitting bands 15 and 16 need to hold sensors, which sensors detect the tension of the transmitting bands 15 and 16. With data from these sensors and with data from the hip sensors 31 the processor 11 can perform the necessary calculations. According to a preferred embodiment the shape of the transmitting bands 15 and 16 are band-shaped. According to another preferred embodiment the shape of the transmitting bands 15 and 16 are string-shaped.

The force transmitting knee band 18 can be made from flexible or rigid material. If the force transmitting knee band 18 is made from a rigid material like metal or plastic, it will be possible to position the front part connecting means 21 and the transmitting band 16 further distance from the body and these parts therefore do not touch the skin of the user.

Examples

Example 1: Motion assistance device 100 with four motors 2

The preferred embodiment of this example is shown in Fig. 1. - 4. and Fig. 6. - 7b. The motion assistance device 100 of this embodiment comprises a motor housing 2, a main frame 3 and a supporting device 13.

The motor housing 1 contains four motors 2, four anti friction casters 4, two front disks 8f and two back disks 8b, a processor 11, a memory 12, a first signal transfer device 26a, a band flexing spring 28 for every disk 8, a hip sensor 31 for every disk 8 and a freewheel 29 for every disk.

The main frame 3 is a belt, which contains a beltbucket 5. A battery docking unit 7 is attached to the main frame 3. A battery 6 is docked into the battery docking unit 7.

The supporting device 13 for each leg of the user 200 contains a force transmitting knee band 18, a front part connecting means 21 and a rear part connecting means 22, a knee sensor 23, a stretch detecting device 24, a second signal transfer device 26b, a battery 32 for the second signal transfer device 26b and an opening 30.

A rear force transmitting band 15 and a front force transmitting band 16 for each leg of the user 200 link the supporting device 13 to the motor housing 1.

The knee sensor 23 is a stretch detecting stamp, the length of which increases as the knee is bending.

The signal transfer devices 26a and 26b use Bluetooth technology .

The hip sensor 31 is an optical absolute encoder, which measures the movement parameters of the corresponding disk 8.

When the user 200 starts moving and for example lifts his/her right thigh and the right knee is bending, the motor 2 on the front right side coils up the front force transmitting band 16 of the right leg to the front disk 8f on the right side and at the same time the motor 2 on the back left side coils up the rear force transmitting band 15 of the left leg to the back disk 8b on the left side. The other transmitting bands 15 and 16 are coiled down passively, without the help of the corresponding motor 2.

Example 2: Motion assistance device 100 with two motors 2

The preferred embodiment of this example is shown in Fig. 1. - 2. and Fig. 5. - 7b. The motion assistance device 100 of this embodiment comprises a motor housing 2, a main frame 3 and a supporting device 13. The motor housing 1 contains two bidirectional motors 2, four anti-friction casters 4, two front disks 8f and two back disks 8b, a processor 11, a memory 12, a first signal transfer device 26a, a band flexing spring 28 for every disk 8, a hip sensor 31 for every disk 8, a clutch for every disk and a freewheel 29 for every disk.

The main frame 3 is a belt, which contains a beltbucket 5, and a battery docking unit 7 is attached to the main frame 3. A battery 6 is docked into the battery docking unit 7.

The supporting device 13 for each leg of the user 200 contains a force transmitting knee band 18, a front part connecting means 21 and a rear part connecting means 22, a knee sensor 23, a stretch detecting device 24, a second signal transfer device 26b, a battery 32 for second signal transfer device 26b and an opening 30.

The signal transfer devices 26a and 26b use Bluetooth technology .

The hip sensor 31 is an optical absolute encoder, which measures the movement parameters of the disk. When the user 200 starts moving and for example the user 200 lifts his/her right thigh and the right knee is bending, the motor 2 on the right side coils up the front force transmitting band 16 of the right leg to the front disk 8f and the clutch detaches the disk 8b from that motor 2. At the same time the motor 2 on the left side coils up the rear force transmitting band 15 of the left leg to the back disk 8b and the clutch detaches the front disk 8f from that motor 2. The other transmitting bands 15 and 16 are coiled down passively from the detached disks 8f and 8b without the help of the corresponding motor 2.

Example 3: Using the motion assistance device 100 for walking From the beginning of the walking the motion assistance device 100 monitors and maps the movement of the user 200. The processor 11 and memory 12 save the obtained information. From this information the simple active mode chooses the right algorithm for the assistance of the walking. The teaching active mode create the right algorithm for the assistance of the walking based on two or three repeated motion cycle.

The algorithm for the walking motion is shown in Table 1:

Fig. 9 visualises the phases of the walking movement of a human in view of the steps of the algorithm of Table 1. The zero angle for the knee angle is when both lower limbs of the user 200 is fully straight. The zero angle for the hip angle is the same position, namely when the user 200 lower limbs are fully straightened. Example 4: Using the motion assistance device 100 for running

From the beginning of the walking the motion assistance device 100 monitors and maps the movement of the user 200. The processor 11 and memory 12 save the obtained information. From this information the simple active mode chooses the right algorithm for the assistance of the running. The teaching active mode create the right algorithm for the assistance of the running based on two or three repeated motion cycle. The algorithm for the running motion is shown in Table 2:

Fig. 10 visualises the phases of the running movement of a human in view of the steps of the algorithm of Table 2. The zero angle for the knee angle is when a lower limb of the user 200 is fully straightened. The zero angle for the hip angle is the same position, namely when one of the lower limbs of the user 200 is fully straightened. Example 5: Using the motion assistance device 100 for climbing stairs

From the beginning of the walking the motion assistance device 100 monitors and maps the movement of the user 200. The processor 11 and memory 12 save the obtained information. From this information the simple active mode chooses the right algorithm for the assistance of the climbing stairs motion.

The teaching active mode create the right algorithm for the assistance of the climbing stairs motion based on two or three repeated motion cycle.

The algorithm for the climbing motion is shown in Table 3:

Fig. 11 visualises the phases of the climbing movement of a human in view of the steps of the algorithm of Table 3. The zero angle for the knee angle is when both lower limbs of the user 200 is fully straight. The zero angle for the hip angle is the same position, namely when the user 200 lower limbs are fully straightened.

Example 6: Functions created by the motion assistance device 100

Fig. 12. shows the functions of the knee angle and hip angle in the sprint, run and walk gait cycle. The motion assistance device 100 measures and stores the angle data shown in these figures .

As will be obvious for a person skilled in the art, the motion assistance device 100 of the present invention can be used by humans having two legs. Persons having only one leg cannot utilize the present invention, as the moving phases of the legs relative to each other is an important factor when determining the next step of the movement. On the other hand, the motion assistance device 100 can be useful also in cases where one of the legs or both legs of the human user 200 have defects, or if some parts of the legs have artificial parts. Anyway, the motion assistance device 100 of the present invention is primarily designed for use by healthy people.

Claims

1.Motion assistance device (100) comprising i) a motor housing (1), the motor housing (1) contains motors (2), at least four disks (8) functionally connected to the motors (2), band flexing springs (28) for every disk (8) for keeping the band tense, and hip sensors (31) for every disk (8), a processor (11), a memory (12), at least one signal transfer device (26a), ii) a main frame (3) for mounting the motion assistance device (100) around the hip of the user (200), which contains a battery (6) and a battery docking unit (7), and the main frame (3) holds the motor housing (1); iii) a front force transmitting band (15) and a back force transmitting band (16) for running along the opposite sides of each leg of the user (200), and a supporting device (13) suitable for attaching it around the knee of the user (200), where the force transmitting bands (15,

16) connect via connection means (21, 22) the supporting device (13) with the disks (8) in the motor housing (1) at the respective sides of the user (200), characterized in that each supporting device (13) further comprises a knee sensor (23) and a signal transfer device (26b).

2. The motion assistance device according to claim 1, characterized in that the signal transfer device (26a) in the motor housing (1) and/or the signal transfer device (26b) of the supporting device (13) is/are wireless signal transfer device(s).

3.Motion assistance device (100) according to claim 1 or 2, characterized in that the motor housing (1) contains two motors (2) with clutches; or four motors (2)with or without clutches;

4.Motion assistance device (100) according to claim 1 or 2, characterized in that the motor housing (1) contains six motors (2) with or without clutches, having two strings for the movement of the heels.

5.Motion assistance device (100) according to any of claims 1 to 4, characterized in that it further comprises at least one anti-friction casters (4) for every force transmitting bands (15, 16).

6.Motion assistance device (100) according to any of claims 1 to 5, characterized in that it further comprises at least one freewheel (27) for every disk (8).

7.Motion assistance device (100) according to any of claims 1 to 6, characterized in that the knee sensor (23) is a stretch detecting stamp and the supporting device (13) further comprises a force transmitting knee band (18) and an opening (30).

8.Motion assistance device (100) according to any of claims 1 to 7, characterized in that the supporting device (13) further comprises a stitching (25) and/or connecting means {21).

9.Motion assistance device (100) according to any of claims 1 to 8, characterized in that the hip sensors (31) are optical absolute encoders.