Functional improvement support device and its control program

Abstract

To provide a function improvement support device and a function improvement support method, which allows recognition of an improvement situation of a walking function by a subject, and which may be useful for mental improvement by sense of accomplishment.SOLUTION: When a subject executes rehabilitation by walking motion using a wearable motion assist device, the subject enjoys sense of accomplishment in improvement of a walking function, while viewing and hearing a motion advice for improvement of the walking function.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a function improvement support device and The control program In particular, a function improvement support device for encouraging a subject to be proactive in their rehabilitation through walking using a wearable movement assist device, and The control program This is what we are trying to propose. [Background technology]

[0002] Progressive neuromuscular diseases such as amyotrophic lateral sclerosis (ALS) and muscular dystrophy (MD) are caused by nerve or muscle damage, gradually resulting in muscle weakness and motor dysfunction. There are no curative treatments for these diseases, and drug treatments have been unable to do more than slow the natural progression of symptoms.

[0003] Various power assist devices have been widely used to assist or substitute for the movements of physically disabled people who have lost muscle strength or elderly people who have weakened muscle strength. For example, a wearable motion assist device has been proposed that can control and assist movement based on bioelectric potentials associated with voluntary muscle activity according to the wearer's intentions (see Patent Document 1).

[0004] In recent years, such wearable motion-assist devices have been used in treatments aimed at maintaining and improving the walking function of patients with progressive neuromuscular diseases. These wearable motion-assist devices move in unison with the patient to assist walking movements based on physiological and motor information such as bioelectrical signals (BES) of the lower limb muscles, joint angles, and ground reaction forces.

[0005] A subject wearing this wearable motion-assist device can repeatedly walk based on the patient's motor intentions without placing a strain on the neuromuscular system. As a result, the wearable motion-assist device promotes the structural development and strengthening of neural loops, enabling treatment that activates the nervous system to maintain and improve the patient's motor function. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-95561 Summary of the Invention [Problem to be solved by the invention]

[0007] Incidentally, in rehabilitation using this wearable movement-assist device to assist the subject in walking, the subject is thinking about various things in addition to concentrating on walking.

[0008] If this thinking could be directed towards improving treatment through rehabilitation, the effectiveness of treatment would increase and recovery would be accelerated, but simply providing advice to encourage walking would likely be insufficient to improve the subject's motivation.

[0009] It is desirable that the subject actually undergo rehabilitation through walking using a wearable movement-assist device and be able to recognize through feedback the improvement in his or her walking function so that walking function approaches the ideal state.

[0010] The present invention has been made in consideration of the above points, and provides a function improvement support device that allows a subject to recognize the state of improvement in walking function and also helps improve mental health through the sense of accomplishment achieved. The control program This is what we are trying to propose. [Means for solving the problem]

[0011] In order to solve this problem, the present invention provides a device that applies power to a subject according to each walking phase that constitutes the walking motion of the subject. formulaa biosignal detection unit disposed on a body surface portion of the subject based on a joint associated with the subject's lower limb movement and having a group of electrodes for detecting a biopotential signal of the subject; a voluntary control unit causing the drive unit to generate a power according to the subject's will based on the biopotential signal acquired by the biosignal detection unit; a joint circumference detection unit detecting a physical quantity around the joint associated with the subject's lower limb movement based on an output signal from the drive unit; an autonomous control unit identifying walking phases according to a walking task of the subject based on the physical quantity detected by the joint circumference detection unit and causing the drive unit to generate a power corresponding to each walking phase; a drive current generation unit synthesizing control signals from the voluntary control unit and the autonomous control unit and supplying a drive current according to the synthesized control signal to the drive unit; and floor reaction force sensors detecting a pressure distribution on the soles of the left and right feet of the subject. a signal normalization unit that normalizes the bioelectric potential signal detected by the biosignal detection unit to a first signal pattern expressed in a plane coordinate system of time and amplitude for each gait cycle, using the physical quantity detected by the joint circumference detection unit and the gait cycle calculated by the gait synchronization calculation unit as a reference; a difference calculation unit that compares the first signal pattern obtained from the signal normalization unit with a second signal pattern corresponding to a reference healthy person, and calculates a difference in signal level for each walking time point in the gait cycle based on the comparison result; an action advice generation unit that generates action advice for the gait cycle based on the calculation result of the difference calculation unit so as to bring the first signal pattern closer to the second signal pattern in a matching direction and reduce the amount of difference at the same time; and an action advice presentation unit that converts the action advice generated by the action advice generation unit into either or both of image information and audio information and presents it to the subject.

[0012] moreover In the present invention, a device for applying power to a subject according to each walking phase constituting the walking motion of the subject is provided. formula Functional improvement support using motion assist devices Device control program the wearable action-assist device has a drive unit that is actively or passively driven in conjunction with a lower limb movement of the subject, and combines a voluntary control that causes the drive unit to generate a power according to the will of the subject based on a biopotential signal acquired from a body surface part of the subject with reference to a joint associated with the lower limb movement of the subject, and an autonomous control that identifies walking phases according to a walking task of the subject based on physical quantities around the joints associated with the lower limb movement of the subject detected based on an output signal from the drive unit, and causes the drive unit to generate a power corresponding to each walking phase, and supplies a drive current according to the combined control signal to the drive unit, A control unit of the function improvement support device The system is configured to execute a series of processes including a first step of normalizing the biopotential signals to a first signal pattern expressed in a plane coordinate system of time and amplitude for each gait cycle, using the gait cycle calculated based on the physical quantities around the joints and the detection results of the pressure distribution on the soles of the left and right feet of the subject as a reference; a second step of comparing the first signal pattern obtained from the first step with a second signal pattern corresponding to a reference healthy person and calculating the difference in signal level for each walking point in the gait cycle based on the comparison results; a third step of generating operation advice for the gait cycle based on the calculation results from the second step, so as to bring the first signal pattern closer to the second signal pattern in a direction that is consistent with it and reduce the amount of difference; and a fourth step of converting the operation advice generated in the third step into either image information or audio information, or both, and presenting the advice to the subject.

[0013] Furthermore, in the present invention, the movement advice generating unit generates movement advice so as to focus on the movement phase including the walking time point with the highest deviation rate of the difference amount among the movement phases that make up the walking cycle.

[0014] As a result, the functional improvement support device generates movement advice focusing on the movement phase that is most in need of improvement in the walking cycle for each step, making it possible to present the subject with the most optimal movement advice.

[0015] Furthermore, in the present invention, the operational advice presenting unit converts an image representing the matching direction and difference amount of the first signal pattern relative to the second signal pattern as image information from the operational advice so as to be superimposed on the first signal pattern and the second signal pattern normalized in a plane coordinate system by the signal normalization unit.

[0016] As a result, the functional improvement support device makes it possible to check one's own walking movement, step by step, while visually observing the normalized planar image to see how much the first signal pattern corresponding to one's own walking movement differs from the second signal pattern corresponding to the walking movement of a healthy person.

[0017] Furthermore, in the present invention, the point setting unit calculates the degree to which the difference between each walking point in the walking cycle is eliminated based on the calculation results of the difference calculation unit obtained in a feedback manner, and sets points according to the calculation results.

[0018] As a result, with the function improvement support device, as the subject's walking function improves through walking movements using the wearable movement assist device, points are added according to the improvement status, thereby increasing the subject's sense of accomplishment and leading to mental improvement.

[0019] Furthermore, in the present invention, the point setting unit processes billing so that the set points are returned as part of the usage fee for the wearable movement-assist device. As a result, with the function improvement support device, the subject can enjoy an incentive of being able to reduce the usage fee in proportion to the treatment effect while undergoing rehabilitation through walking using the wearable movement-assist device, which can contribute to improving the subject's motivation when engaging in rehabilitation.

[0020] Further, in the present invention, in a function improvement support method using a wearable action-assist device that applies to a subject power corresponding to each walking phase constituting the walking movement of the subject, the wearable action-assist device has a drive unit that is actively or passively driven in conjunction with a lower limb movement of the subject, and combines a voluntary control that causes the drive unit to generate power in accordance with the subject's will based on a biopotential signal acquired from a body surface part of the subject with reference to a joint associated with the lower limb movement of the subject, and an autonomous control that identifies each walking phase in accordance with a walking task of the subject based on a physical quantity around the joint associated with the lower limb movement of the subject detected based on an output signal from the drive unit and causes the drive unit to generate power corresponding to each walking phase, and supplies a drive current corresponding to the combined control signal to the drive unit, and combines the biopotential signal with the physical quantity around the joint. The method includes a first step of normalizing each gait cycle to a first signal pattern expressed in a plane coordinate system of time and amplitude, using the gait cycle calculated based on the detection results of the pressure distribution on the soles of the left and right feet of the subject as a reference; a second step of comparing the first signal pattern obtained from the first step with a second signal pattern corresponding to a reference healthy person and calculating the difference in signal level for each walking point in the gait cycle based on the comparison results; a third step of generating behavior advice for the gait cycle based on the calculation results from the second step, so as to bring the first signal pattern closer to the second signal pattern in a direction that matches the first signal pattern and reduce the amount of difference; and a fourth step of converting the behavior advice generated in the third step into either image information or audio information, or both, and presenting it to the subject.

[0021] As a result, the function improvement support device Control program When a subject performs rehabilitation through walking movements using a wearable movement-assist device, the subject can enjoy a sense of accomplishment from improving their walking function while receiving audiovisual advice on movements to improve their walking function. [Effects of the Invention]

[0022] According to the present invention, a function improvement support device that can be used not only to improve the walking function of a subject but also to improve the mental state of the subject, The control program This can be achieved. [Brief explanation of the drawings]

[0023] [Figure 1] 1 is a conceptual diagram illustrating a walking assistance system according to an embodiment of the present invention. [Figure 2] 1 is a perspective view showing the external configuration of a wearable action-assist device according to an embodiment of the present invention; [Figure 3] 1 is a block diagram showing an internal configuration of a wearable action assist device according to an embodiment of the present invention. [Figure 4] FIG. 1 is a block diagram showing an internal configuration of a function improvement assistance device using a wearable action assist device. [Figure 5] 1 is a chart showing information about subjects. [Figure 6] 10 is a graph showing a second signal pattern of a biopotential signal obtained from a right knee extensor muscle of a healthy subject. [Figure 7] 10 is a graph showing a second signal pattern of a biopotential signal obtained from a right knee extensor muscle of a healthy subject. [Figure 8] 10 is a graph showing a normalized first signal pattern of a biopotential signal. [Figure 9] 1 is a normalized graph in which a first signal pattern and a second signal pattern are superimposed. [Figure 10] This is a graph in which image information is added to the normalized graph shown in FIG. 8. DETAILED DESCRIPTION OF THE INVENTION

[0024] An embodiment of the present invention will be described in detail below with reference to the drawings.

[0025] (1) Configuration of the walking assistance system according to this embodiment 1 shows a walking assistance system 1 according to this embodiment. The walking assistance system 1 includes a wearable action-assist device 2 that assists the movement of a subject P, and a walking assistance device 3 that assists the subject P in rehabilitation through walking. The wearable action-assist device 2 and the walking assistance device 3 are connected to each other via wire or wirelessly so as to be able to communicate with each other.

[0026] First, the walking assistance device 3 is configured such that a pair of left and right frames 6L and 6R are curved and erected from the tip of the treadmill 5 on either side of the treadmill 5, and the subject P can grasp the end portions of both frames 6L and 6R with both hands.

[0027] The treadmill 5 has a walking belt 7 that moves in a circular motion due to the rotation of rollers. The rotation speed of the rollers can be changed in response to actuator drive, thereby changing the circulation speed of the walking belt 7.

[0028] The walking assistance device 3 has a subframe (not shown) that bridges between the left frame 6L and the right frame 6R that are erected from the treadmill 5, and is provided with a monitor 8, for example, a liquid crystal display, that displays the results of operations performed by the operating unit and various information necessary for assisting the subject in walking.

[0029] In this way, in the walking assistance system 1, the subject P wearing the wearable motion-assist device 2 can support rehabilitation through walking by holding one end of the pair of left frame 6L and right frame 6R of the walking assistance device 3 with both hands to stabilize his / her posture during walking.

[0030] (2) Configuration of the wearable action assist device according to this embodiment 2 shows a wearable action-assist device 2 according to this embodiment. The wearable action-assist device 2 is a device that applies power to a subject according to each walking phase that constitutes the walking motion of the subject, and operates by detecting bioelectrical signals (surface myoelectric potentials) that are generated when muscle force is generated by signals from the brain and the movement angles of the hip joints and knee joints of the wearer, and applying driving force from a drive mechanism based on these detection signals.

[0031] The lower limb type wearable action-assist device 2 in this embodiment includes a waist frame 10 attached to the waist of the subject, a lower limb frame 11 attached to the lower limbs of the wearer, a plurality of drive units 12L, 12R, 13L, 13R provided on the lower limb frame 11 corresponding to the joints of the wearer, cuffs 14L, 14R, 15L, 15R as assist force application members attached to the lower limb frame 11 so as to apply the forces of the drive units 12L, 12R, 13L, 13R to the wearer from the front or the back, a control device 30 (see FIG. 3 described later) that controls the drive units 12L, 12R, 13L, 13R based on signals resulting from the wearer's lower limb movements, a back unit 16 equipped with the control device, and an operation unit (not shown) used by a caregiver.

[0032] The control device 30 (FIG. 3) can drive the lower limb frames 11 relatively around the output axes of the actuators of the drive units 12L, 12R, 13L, and 13R corresponding to the joints of the subject. Each of the drive units 12L, 12R, 13L, and 13R is equipped with a group of sensors for detecting the drive torque and rotation angle of the actuator. The back unit 16 is equipped with a battery unit (not shown) for supplying power to drive the entire device.

[0033] The waist frame 10 is a member that is roughly C-shaped in plan view and opens forward to receive the waist of the subject and surround it from its rear to both left and right sides. It has a rear waist frame portion 17 located behind the subject, and a left waist frame portion 18L and a right waist frame portion 18R that extend forward while curving from both ends of the rear waist frame portion 17.

[0034] The left and right waist frame sections 18L, 18R are connected to the rear waist frame section 17 via an opening adjustment mechanism (not shown). The bases of the left and right waist frame sections 18L, 18R are inserted and held within the rear waist frame section 17 so as to be slidable in the left-right direction.

[0035] The lower limb frame 11 includes a right lower limb frame 19R attached to the right lower limb of the subject, and a left lower limb frame 19L attached to the left lower limb of the subject. The left lower limb frame 19L and the right lower limb frame 19R are formed symmetrically.

[0036] The left lower leg frame 19L includes a left thigh frame 20L positioned on the left side of the subject's left thigh, a left lower leg frame 21L positioned on the left side of the subject's left lower leg, and a left lower leg frame 22L on which the sole of the subject's left leg (or the sole of the left shoe, if shoes are worn) is placed. The left lower leg frame 19L is connected to the tip of the left waist frame 18L via a waist connecting mechanism 23L.

[0037] The right lower limb frame 19R includes a right thigh frame 20R located on the right side of the subject's right thigh, a right lower leg frame 21R located on the right side of the subject's right lower leg, and a right lower leg frame 22R on which the sole of the subject's right leg (or the sole of the right shoe, if wearing shoes) is placed. The right lower limb frame 21R is connected to the tip of the right waist frame 18R via a waist connection mechanism 23R.

[0038] The waist frame 10 (rear waist frame 17, right waist frame 18R, and left waist frame 18L) and the lower limb frame 11 (right lower limb frame 19R and left lower limb frame 19L) have a frame body formed in the shape of an elongated plate made of, for example, a metal such as stainless steel or carbon fiber, and are formed to be lightweight and highly rigid. In this embodiment, carbon fiber reinforced plastic (CFRP) and extra super duralumin, an aluminum alloy, are used as strength members.

[0039] The cuffs 14L, 14R, 15L, 15R are provided one each on the left thigh frame 20L, the right thigh frame 20R, the left lower leg frame 21L, and the right lower leg frame 21R.

[0040] The cuffs 14L, 14R (hereinafter referred to as "thigh cuffs") provided on the left thigh frame 20L and the right thigh frame 20R are supported by thigh cuff support mechanisms 24L, 24R attached to the lower ends of the thigh frame bodies. The thigh cuffs 14L, 14R have an arc-shaped curved attachment surface that can be fitted and placed against the subject's thigh. A fitting member is attached to the attachment surface of the thigh cuffs 14L, 14R so that they can fit tightly against the subject's thigh without any gaps.

[0041] The cuffs 15L, 15R (hereinafter referred to as "calf cuffs") provided on the left crus frame 21L and right crus frame 21R are supported by crus cuff support mechanisms 25L, 25R attached to the upper ends of the upper elements. The crus cuffs 15L, 15R have an arc-shaped attachment surface that can be fitted and placed against the subject's crus. A fitting member is attached to the attachment surface of the crus cuffs 15L, 15R so that they fit snugly against the subject's crus.

[0042] When the wearable action-assist device 2 is actually worn on a subject, dedicated shoes 26L, 26R are worn on the left and right feet, respectively, lower leg cuffs 15L, 15R are worn on the left and right lower legs, respectively, and thigh cuffs 14L, 14R are worn on the left and right thighs, respectively. Then, belts or the like are fastened to the shoes and cuffs so that the feet, lower legs, and thighs are integrated with the corresponding frames.

[0043] The dedicated shoes 26L, 26R are configured as a pair of left and right shoes, and hold the subject's feet from the toes to the ankles in a tight fit, and also have floor reaction force sensors (FRF sensors, which will be described later) provided on the soles. 60 ) the load can be measured.

[0044] In this way, the wearable action-assist device 2 can control and assist walking movements based on bioelectric potential signals accompanying voluntary muscle activity according to the intention of the subject wearing the device.

[0045] (3) Internal system configuration of the wearable motion assist device Fig. 3 is a block diagram showing the configuration of the control system of the wearable action-assist device 2. As shown in Fig. 3, the control system 2X of the wearable action-assist device 2 includes a control device 30 that performs overall control of the entire system, a data storage unit 31 in which various data is stored in a database so as to be readable and writable in response to commands from the control device 30, and drive units 12L, 12R, 13L, and 13R that are actively or passively driven in conjunction with the movement of the lower limbs of the subject.

[0046] In addition, a potentiometer 32 that detects the rotation angle of the output shaft is provided coaxially with the output shaft of the actuator in the drive units 12L, 12R, 13L, and 13R, and is configured to detect the joint angle corresponding to the movement of the subject's lower limbs.

[0047] Furthermore, an absolute angle sensor 33 for measuring the absolute angle of the thigh relative to the vertical direction is mounted on the lower limb frame 11. This absolute angle sensor 33 is composed of an acceleration sensor and a gyro sensor, and is used for sensor fusion, which is a method of extracting new information using data from multiple sensors.

[0048] To calculate the absolute thigh angle, a first-order filter is used to remove the effects of translational motion and temperature drift in each sensor, and this first-order filter is calculated by adding weighted values ​​obtained from each sensor.

[0049] If the absolute angle of the thigh relative to the vertical direction is θabs(k), the angular velocity obtained by the gyro sensor is ω, the sampling period is dt, and the acceleration obtained by the acceleration sensor is α, then θabs(t) can be expressed as the following equation (1).

number

[0050] A biosignal detection unit 40 having a biosignal detection sensor (group of electrodes) is placed on the body surface of the subject (mainly the body surface of the thigh) based on the joint associated with the subject's lower limb movement, and is configured to detect bioelectric potential signals for moving the subject's knee joint.

[0051] The data storage unit 31 stores a command signal database 41 and a reference parameter database 42. The control device 30 is configured, for example, by a CPU (Central Processing Unit) chip having a memory, and includes an optional control unit 50, an autonomous control unit 51, a phase identification unit 52, and a gain change unit 53.

[0052] The optional control unit 50 controls the drive units 12L, 12R, 13L, and 13R to generate power according to the subject's will, based on the biopotential signal acquired by the biosignal detection unit 40. Specifically, the optional control unit 50 supplies a command signal corresponding to the detection signal of the biosignal detection unit 40 to the power amplification unit 54. The optional control unit 50 applies a predetermined command function f(t) or gain P to the biosignal detection unit 40 to generate the command signal. This gain P is a preset value or function, and can be adjusted via a gain change unit 53 using an external input.

[0053] It is also possible to select a method of controlling the drive torque (torque magnitude and rotation angle) of the actuator based on the angle data of the knee joint detected by the potentiometer 32. This method is effective when the degree of gait disorder associated with the subject's motor symptoms is relatively mild, or when the subject's skin is expected to be wet with sweat and there is a possibility that input of a biological signal from the biological signal detection unit 40 will not be obtained.

[0054] The data on the knee joint angle detected by the potentiometer 32, the data on the absolute angle of the thigh relative to the vertical direction detected by the absolute angle sensor 33, and the biosignal detected by the biosignal detection unit 40 are input into a reference parameter database 42.

[0055] Additionally, the soles of the pair of dedicated shoes 26L, 26R are provided with FRF (Floor Reaction Force) sensors 60 to detect the pressure distribution on the soles of the subject's left and right feet. The FRF sensors 60 can measure the load acting on the soles of the feet separately for the forefoot (toes) and the rearfoot (heel) separately.

[0056] This FRF sensor 60 may be composed of, for example, a piezoelectric element that outputs a voltage according to the applied load or a sensor whose capacitance changes according to the load, and can detect changes in load due to weight shift and whether or not the wearer's legs are in contact with the ground.

[0057] Furthermore, with the pair of dedicated shoes 26L, 26R, the center of gravity position can be determined from the balance of the loads on the soles of the left and right feet based on the detection results of each FRF sensor 60. In this way, with the pair of dedicated shoes 26L, 26R, it is possible to estimate to which side of the subject's left or right foot the center of gravity is biased, based on the data measured by each FRF sensor 60.

[0058] In addition to the shoe structure, each of the dedicated shoes 26L, 26R has an FRF sensor 60, an FRF control unit 61 consisting of an MCU (Micro Control Unit), and a transmitter 62. The output of the FRF sensor 60 is converted into a voltage via a converter 63, and then input to the FRF control unit 61 after high frequency bands are cut off via an LPF (Low Pass Filter) 64.

[0059] The FRF control unit 61 determines whether or not the subject has ground contact and load changes due to weight shifts based on the detection results of the FRF sensor 60, and also determines the center of gravity position according to the load balance between the soles of the left and right feet. The FRF control unit 61 transmits the determined center of gravity position as FRF data to the transmission unit. 62The signal is transmitted wirelessly to a receiving unit 65 in the device body via the

[0060] The control device 30 receives the FRF data wirelessly transmitted from the transmitter 62 of each dedicated shoe 26L, 26R via the receiver 65, and then stores the load and center of gravity position on the soles of the left and right feet based on the FRF data in the reference parameter database 42 of the data storage unit 31.

[0061] The phase identification unit 52 compares the knee joint angle data detected by the potentiometer 32 and the load data detected by the FRF sensor 60 with the knee joint angle and load of the reference parameters stored in the reference parameter database 42. Based on the comparison result, the phase identification unit 52 identifies the phase of the subject's movement.

[0062] Then, when the autonomous control unit 51 obtains the control data for the phase identified by the phase identification unit 52, it generates a command signal according to the control data for this phase and supplies the command signal to the power amplification unit 54 to cause the drive units 12L, 12R, 13L, and 13R to generate this power.

[0063] Furthermore, the gain adjusted by the gain change unit 53 described above is input to the autonomous control unit 51, which generates a command signal according to this gain and outputs it to the power amplification unit 54. The power amplification unit 54 controls the current that drives the actuators of the drive units 12L, 12R, 13L, and 13R to control the magnitude of the torque and the rotation angle of the actuators, thereby applying an assist force from the actuators to the knee joint of the subject.

[0064] In this way, the autonomous control unit 51 identifies each walking phase according to the walking task of the subject based on the physical quantities detected by the joint circumference detection unit (potentiometer 32 and absolute angle sensor 33), and causes the drive units 12L, 12R, 13L, and 13R to generate power corresponding to each walking phase.

[0065] The power amplifier (drive current generator) 54 combines the control signals from the voluntary control unit 50 and the autonomous control unit 51, amplifies the drive current corresponding to the combined control signal, and supplies it to the actuators of the drive units 12L, 12R, 13L, and 13R. The torque of these actuators is transmitted as an assist force to the knee joint of the subject via the lower limb frame.

[0066] (4) Configuration of the Function Improvement Support Device According to the Present Embodiment In the present invention, a function improvement support device 70 (see FIG. 4, which will be described later) using the wearable action-assist device 2 described above contributes not only to improving the walking function of the subject but also to improving the mental health of the subject.

[0067] As a premise, the biopotential signals of the lower limb muscles measured using the wearable motion-assist device 2 may be useful for evaluating the walking function of the subject, because the subject's muscle activity is measured every time walking therapy is performed using the wearable motion-assist device 2. The biopotential signals reflect changes in the subject's neuromuscular system caused by action potentials generated during movement control.

[0068] The signal patterns of bioelectrical signals obtained from the skin surface around the lower limb muscles change depending on muscle activity during walking.

[0069] During normal walking of a healthy person not wearing the wearable motion-assist device 2, the signal pattern of the biopotential signal will be characteristic of each measurement site. Similarly, the signal pattern of the biopotential signal of a subject wearing the wearable motion-assist device 2 is also thought to have characteristics, and analyzing this signal pattern will make it possible to record the activity of the neuromuscular system during walking. Furthermore, the relationship between the walking ability of the subject and the signal pattern of the biopotential signal measured when walking while wearing the wearable motion-assist device 2 may be applicable to the gait evaluation of subjects undergoing treatment.

[0070] For this reason, in the present invention, the signal pattern of the biopotential signal obtained from the subject undergoing treatment using the wearable action-assist device 2 is quantified, and evaluated by comparing it with the signal pattern of the biopotential signal corresponding to that of a healthy subject, thereby confirming the correlation between the signal pattern and the walking ability of the subject.

[0071] This functional improvement support device 70 is a control system component provided in the control device 30 of the wearable action-assist device 2 described above, and includes a walking synchronization calculation unit 71, a signal normalization unit 72, a difference calculation unit 73, an action advice generation unit 74, an action advice presentation unit 75, and a point setting unit 76, as shown in FIG. 4 .

[0072] First, biopotential signals and data related to a walking test (gait cycle) are acquired from the subject using the wearable motion-assist device 2. Specifically, in treatment using the wearable motion-assist device 2 for a subject suffering from a progressive neuromuscular disease, the subject needs to walk for approximately 20 to 40 minutes per walking test. During this time, the wearable motion-assist device 2 measures biopotential signals obtained from the extensor and flexor muscles of the left and right knee joints and hip joints, and floor reaction forces (FRF data) of both legs as time-series data.

[0073] The results of time-series data measured during treatment using the wearable movement-assist device on seven subjects (Patient ID: A to G) with a progressive neuromuscular disease were used. The subjects also periodically performed a 2-minute walking test (2MWT), which measures the walking distance in 2 minutes, without wearing the wearable movement-assist device 2, in order to ensure accurate gait evaluation.

[0074] For seven subjects, walking tests were performed at a single facility within the past two years. The number of walking tests and 2MWT results performed during this study period varied for each subject. The disease type, gender, height, weight, and number of 2MWT results for each subject are shown in the table in Figure 5. In this table, MD, ALS, IBM, and SBMA represent muscular dystrophy, amyotrophic lateral sclerosis, inclusion body myositis, and spinal and femoral muscular atrophy, respectively.

[0075] The signal patterns of the biopotential signals obtained from these subjects are compared with the signal patterns of the biopotential signals obtained when a healthy person wearing the wearable action-assist device 2 is walking, to determine the similarity.

[0076] In the walking assistance system 1 shown in FIG. 1 described above, bioelectric potential signals obtained from the right knee extensor muscles of healthy subjects were measured while they walked on a treadmill 5 while wearing a wearable motion-assist device 2. Three healthy adult males aged 21 to 23 (Participants X to Z) were selected as the healthy subjects. The control parameters of the wearable motion-assist device 2 and the running speed of the walking belt 7 of the treadmill 5 were adjusted in advance to a walking speed comfortable for each participant.

[0077] The wearable motion-assist device 2 was used to measure and process the biopotential signals obtained from the right knee extensor muscles of participants X to Z. The average value of the signal patterns of the biopotential signals was then calculated for 90 walking cycles per participant, i.e., a total of 270 walking cycles.

[0078] The average value of this signal pattern was used as a standard for healthy subjects and was calculated using the following steps 1 to 5. The biopotential signal was divided into gait cycles starting from the moment of contact of the right heel, detected based on the values ​​of the floor reaction force sensor (FRF sensor 60) (Step 1). The biopotential signal was resampled to 101 points at regular intervals of 0 to 100 during each gait cycle and normalized by the duration of each gait cycle. The resampled values ​​were then interpolated using cubic spline interpolation (Step 2).

[0079] The amplitude of the biopotential signal was normalized for each gait cycle, with the maximum value set to 100 and the base value set to 0 (Step 3). For each sampling point, the average value of 270 biopotential signals was calculated and a signal pattern connecting these average values ​​was obtained (Step 4). The signal pattern obtained above was normalized together with the amplitude using the same method as in Step 3. This signal pattern was used as the gait standard for a healthy subject using the wearable motion-assist device 2 (Step 5).

[0080] Figures 6(A) and 6(B) and Figure 7(A) show the signal patterns of biopotential signals obtained from the right knee extensor muscles for healthy subjects (participants X to Z) walking on a treadmill 5 while wearing the wearable motion-assist device 2. Figure 7(B) shows the average value of a total of 270 walking patterns for the three participants, with the solid line and dashed line indicating the mean value and standard deviation range, respectively. The average pattern shown in Figure 7(B) was used as the reference biopotential signal pattern for healthy subjects to determine the similarity of the signal patterns between the subjects and healthy subjects.

[0081] In order to determine the above-mentioned walking period, the walking synchronization calculation unit 71 shown in FIG. 4 calculates the walking period of the subject based on the detection results of the floor reaction force sensor (FRF sensor 60) that detects the pressure distribution on the soles of the left and right feet of the subject.

[0082] The signal normalization unit 72 normalizes the biopotential signal detected by the biosignal detection unit 40 into a first signal pattern expressed in a plane coordinate system of time and amplitude for each walking cycle, based on the physical quantity detected by the joint circumference detection unit (potentiometer 32 and absolute angle sensor 33) and the walking cycle calculated by the walking synchronization calculation unit 71.

[0083] Specifically, in this embodiment, the wearable action-assist device 2 measures biopotential signals obtained from the right knee extensor muscle of a subject suffering from a progressive neuromuscular disease, and the signal pattern (first signal pattern) of the biopotential signals for each walking cycle is normalized with respect to amplitude and time and shown in FIGS. 8(A) and 8(B).

[0084] Figure 8(A) is a graph showing the normalized results of the measurement results from the first trial, and Figure 8(B) is a graph showing the normalized results of the measurement results three months later. These two normalized graphs are significantly different, and by comparing and analyzing the signal pattern of the biopotential signal obtained from a healthy subject (second signal pattern), it became possible to quantify the difference.

[0085] The difference calculation unit 73 (FIG. 4) compares a first signal pattern of biopotential signals obtained from a subject undergoing treatment using the wearable action-assist device 2 with a second signal pattern of biopotential signals obtained from a healthy subject, and calculates the difference in signal level for each walking point in the walking cycle.

[0086] The solid line in the normalized graph of FIG. 9 indicates a first signal pattern of the biopotential signal obtained from a subject undergoing treatment using the wearable action-assist device 2, and the dashed line in the normalized graph indicates a second signal pattern of the biopotential signal obtained from a healthy subject walking using the wearable action-assist device 2.

[0087] In FIG. 9, the second signal pattern corresponding to the able-bodied person reaches a maximum immediately after the initial contact with the floor, decreases toward the swing phase, and then increases during the swing phase.

[0088] Next, the action advice generating unit 74 generates action advice for the walking cycle based on the calculation result of the difference calculating unit 73 so as to bring the first signal pattern closer to the second signal pattern in a matching direction and at the same time reduce the difference amount.

[0089] Specifically, the action advice generating unit 74 calculates the difference in signal level of the first signal pattern relative to the second signal pattern, including both positive and negative values, for all walking time points in a walking cycle. At this time, the action advice generating unit 74 calculates the amount of difference in signal level of the first signal pattern relative to the second signal pattern as an integral value for each successive walking time point, and determines whether the integral value continues to increase in either the positive or negative direction.

[0090] When the integral value expands to a predetermined value or more in either the positive or negative direction over multiple walking time points, the action advice generation unit 74 generates action advice for the walking cycle so as to bring the first signal pattern closer to the second signal pattern in a matching direction and at the same time reduce the difference amount.

[0091] For example, for a local section (a series of consecutive walking points) where the signal level of the first signal pattern is significantly lower than that of the second signal pattern, the movement advice generation unit 74 generates an arrow mark pointing in the direction of the match, taking into consideration the position of the local section in the walking cycle, and generates a message as movement advice saying, "Try harder for a while after starting to move forward" to encourage a reduction in the difference in signal level.

[0092] On the other hand, for a local section (a series of consecutive walking points) where the signal level of the first signal pattern is significantly higher than that of the second signal pattern, the action advice generation unit 74 generates an arrow mark pointing in the direction of the match, taking into consideration the position of the local section in the walking cycle, and generates the message "move softer once you start moving" as action advice to encourage a reduction in the difference in signal level.

[0093] The action advice presenting unit 75 converts the action advice generated by the action advice generating unit 74 into image information and / or audio information and presents it to the subject. That is, the action advice presenting unit 75 includes the monitor 8 in the walking support device 3 of the walking support system 1 (FIG. 1) described above, and is configured to display an image of the normalized graph shown in FIG. 8 on the monitor 8.

[0094] In Figure 10, which is the same normalized graph as Figure 9 displayed on the monitor 8, the operational advice presenting unit 75 converts an image representing the matching direction and difference amount of the first signal pattern with respect to the second signal pattern as image information from the operational advice so as to be superimposed on the first signal pattern and the second signal pattern normalized in a plane coordinate system by the signal normalizing unit 72.

[0095] That is, as shown in FIG. 10, an image showing the matching direction of the first signal pattern relative to the second signal pattern as image information is displayed as an arrow mark, and an image showing the difference amount is displayed as a message, superimposed on the corresponding local section in the walking cycle.

[0096] Therefore, with the functional improvement support device 70, it is possible to visually check one's own walking movement, step by step, to see how much the first signal pattern corresponding to one's own walking movement differs from the second signal pattern corresponding to the walking movement of a healthy person, as a normalized planar image.

[0097] In this way, with the function improvement support device 70, when the subject performs rehabilitation through walking movements using the wearable movement assist device 2, the subject can enjoy a sense of accomplishment in improving their walking function while hearing and seeing movement advice for improving their walking function.

[0098] Furthermore, in the function improvement support device 70, the point setting unit 76 (Figure 4) calculates the degree to which the difference at each walking point in the walking cycle is resolved based on the calculation results of the difference calculation unit 73 obtained in a feedback manner, and sets points (tokens as substitute currency, etc.) according to the calculation results.

[0099] Specifically, the point setting unit 76 sets an evaluation index J as the squared integral of the difference in signal level of the bioelectrical signal between local sections (0-100%) in a walking cycle (a section of a normalized step), and sets points when the value of the evaluation index J becomes smaller than at the start (when the difference approaches elimination). This evaluation index J may be set so that points are added according to the degree to which it has become smaller than at the start, or may be set to a predetermined threshold value so that points are only set when the threshold is exceeded.

[0100] As a result, with the function improvement support device 70, as the walking function of the subject improves through walking movements using the wearable movement assist device 2, points are added according to the improvement status, thereby increasing the subject's sense of accomplishment and leading to mental improvement.

[0101] (5) Other embodiments As described above, in this embodiment, the case has been described in which only the first signal pattern of the biopotential signal obtained mainly from the subject's right knee extensor muscle is the target for improving walking function, but the present invention is not limited to this, and a signal pattern of the biopotential signal obtained by integrating multiple muscles necessary for the subject's walking may also be applied to improving walking function.

[0102] In this embodiment, the subject is assisted in rehabilitation by walking on the treadmill 5 of the walking assistance device 3, but the present invention is not limited to this. The subject using the wearable motion-assist device 2 may also walk with a movable walker.

[0103] Furthermore, in this embodiment, the case has been described in which the action advice generating unit 74 generates action advice for a walking cycle based on the calculation result of the difference calculating unit 73 so as to bring the first signal pattern closer to the second signal pattern in a matching direction and at the same time reduce the difference amount, but the present invention is not limited to this, and action advice may be generated so as to focus on a movement phase including a walking time point with the highest deviation rate of the difference amount among the movement phases (local sections) that make up the walking cycle.

[0104] As a result, the function improvement support device 70 generates movement advice focusing on the movement phase that is most in need of improvement in the walking cycle for each step, making it possible to present the subject with the most optimal movement advice.

[0105] Furthermore, in the present embodiment, the point setting unit 76 calculates the degree of elimination of the difference at each walking time point in the walking cycle based on the calculation result of the difference calculation unit 73 obtained in a feedback manner, and sets points according to the calculation result. However, in addition to this, the present invention may also perform a charging process so that the set points are refunded as part of the usage fee for the wearable action-assist device 2.

[0106] As a result, with the function improvement support device 70, the subject can undergo rehabilitation through walking movements using the wearable movement support device 2 while enjoying the incentive of reduced usage fees in proportion to the treatment effect, which can contribute to improving motivation when engaging in rehabilitation. [Explanation of symbols]

[0107] 1...walking assistance system, 2...wearable movement assistance device, 2X...control system, 3...walking assistance device, 5...treadmill, 6L...left frame, 6R...right frame, 7...walking belt, 8...monitor, 10...waist frame, 11...lower limb frame, 12L, 12R, 13L, 13R...drive unit, 26L, 26R...dedicated shoes, 30...control device, 31...data storage unit, 32...potentiometer, 33...absolute angle sensor, 40...biological signal detection unit, 41...command signal database base, 42...reference parameter database, 50...optional control unit, 51...autonomous control unit, 52...phase identification unit, 53...gain change unit, 54...power amplification unit, 60...FRF sensor, 61...FRF control unit, 62...transmitter, 63...converter, 64...LPF, 65...receiver, 70...function improvement support device, 71...walking synchronization calculation unit, 72...signal normalization unit, 73...difference calculation unit, 74...action advice generation unit, 75...action advice presentation unit, 76...point setting unit.

Claims

1. A function improvement support device using a wearable motion assist device that applies power to a subject according to each walking phase that constitutes the walking motion of the subject, The wearable action-assist device includes: a drive unit that actively or passively drives the device in conjunction with the movement of the subject's lower limbs; a biosignal detection unit having a group of electrodes arranged on a body surface of the subject based on joints involved in lower limb movements of the subject, for detecting biopotential signals of the subject; an optional control unit that causes the drive unit to generate power according to the subject's will based on the biopotential signal acquired by the biosignal detection unit; a joint circumference detection unit that detects a physical quantity around the joint accompanying a lower limb movement of the subject based on an output signal from the drive unit; an autonomous control unit that identifies walking phases corresponding to the walking task of the subject based on the physical quantities detected by the joint circumference detection unit, and causes the drive unit to generate power corresponding to each walking phase; a drive current generating unit that combines control signals from the optional control unit and the autonomous control unit and supplies a drive current corresponding to the combined control signal to the drive unit; a gait synchronization calculation unit that calculates the gait cycle of the subject based on the detection results of a floor reaction force sensor that detects pressure distribution on the soles of the left and right feet of the subject; a signal normalization unit that normalizes the biopotential signal detected by the biosignal detection unit into a first signal pattern expressed in a plane coordinate system of time and amplitude for each gait cycle, based on the physical quantity detected by the joint circumference detection unit and the gait cycle calculated by the gait synchronization calculation unit; a difference calculation unit that compares the first signal pattern obtained from the signal normalization unit with a second signal pattern corresponding to a reference healthy individual, and calculates a difference in signal level for each walking time point in the walking cycle based on the comparison result; an action advice generator that generates action advice for the walking cycle based on a calculation result of the difference calculator so as to bring the first signal pattern closer to a matching direction with respect to the second signal pattern and reduce an amount of difference; an action advice presentation unit that converts the action advice generated by the action advice generation unit into image information and / or audio information and presents the converted information to the subject; A function improvement support device comprising:

2. The action advice generation unit The action advice is generated so as to focus on a movement phase including a walking time point with the highest deviation rate of the difference amount among the movement phases constituting the walking cycle.

2. The function improvement support device according to claim 1.

3. The operation advice presentation unit an image representing a direction of coincidence and a difference amount of the first signal pattern relative to the second signal pattern is converted from the operation advice as the image information so as to be superimposed on the first signal pattern and the second signal pattern normalized in the plane coordinate system by the signal normalization unit; 3. The function improvement support device according to claim 1 or 2.

4. a point setting unit that calculates the degree of elimination of the difference at each walking time point in the walking cycle based on the calculation result of the difference calculation unit obtained in a feedback manner, and sets points according to the calculation result; 4. The function improvement support device according to claim 1, further comprising:

5. The point setting unit performs billing processing so that the set points are returned as part of a fee for using the wearable action assist device.

5. The function improvement support device according to claim 4.

6. 1. A control program for a function improvement support device using a wearable motion assist device that applies power to a subject according to each walking phase that constitutes the walking movement of the subject, the wearable action-assist device has a drive unit that is actively or passively driven in conjunction with a lower limb movement of the subject, and combines a voluntary control that causes the drive unit to generate a power according to the will of the subject based on a biopotential signal acquired from a body surface part of the subject with reference to a joint associated with the lower limb movement of the subject, and an autonomous control that identifies walking phases according to a walking task of the subject based on physical quantities around the joints associated with the lower limb movement of the subject detected based on an output signal from the drive unit, and causes the drive unit to generate a power corresponding to each walking phase, and supplies a drive current according to the combined control signal to the drive unit; A control unit of the function improvement support device a first step of normalizing the biopotential signals to a first signal pattern expressed in a plane coordinate system of time and amplitude for each gait cycle, the first signal pattern being based on a gait cycle calculated based on physical quantities around the joints and detection results of pressure distribution on the soles of the left and right feet of the subject; a second step of comparing the first signal pattern obtained from the first step with a second signal pattern corresponding to a reference healthy individual, and calculating a difference in signal level for each walking time point in the walking cycle based on the comparison result; a third step of generating action advice for the walking cycle based on the calculation result of the second step so as to bring the first signal pattern closer to the second signal pattern in a matching direction and reduce a difference amount at the same time; a fourth step of converting the action advice generated in the third step into image information and / or audio information and presenting the image information and audio information to the subject; A control program that executes a series of processes.

7. In the third step, The action advice is generated so as to focus on a movement phase including a walking time point with the highest deviation rate of the difference amount among the movement phases constituting the walking cycle.

7. The control program according to claim 6.

8. In the fourth step, An image representing a direction of coincidence and a difference between the first signal pattern and the second signal pattern is converted from the operational advice as the image information so as to be superimposed on the first signal pattern and the second signal pattern normalized in the plane coordinate system in the first step.

8. The control program according to claim 6 or 7.

9. a fifth step of calculating the degree to which the difference between the walking points in the walking cycle is eliminated based on the calculation result of the second step obtained in a feedback manner, and setting points according to the calculation result; 9. The control program according to claim 6, further comprising:

10. In the fifth step, the set points are returned as part of the fee for using the wearable action assist device.

10. The control program according to claim 9.

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