HK1096843B - Wearing type behavior help device, wearing type behavior help device calibration device, and calibration method - Google Patents

Description

Mounting type motion assisting device, calibration device for mounting type motion assisting device, and calibration method

Technical Field

The present invention relates to a mounting type motion assist device, and more particularly, to a mounting type motion assist device that assists or replaces the motion of an installer, a calibration device for a mounting type motion assist device, a calibration method for a mounting type motion assist device, and an improved calibration program.

Background

For disabled persons with diminished muscle strength or elderly persons with reduced muscle strength, it is often difficult for normal persons to simply perform the required actions. Therefore, in order to assist or replace the operation of these people, various booster devices are being developed.

An example of such a booster is a mounted-type motion assist device (hereinafter, simply referred to as "motion assist device") that is mounted on a user (hereinafter, simply referred to as "installer").

Among such motion assist devices, non-patent document "Development of a power assisted Leg for Walking Aid Using EMG and Linux" (Takao Nakai, suwood Lee, Hiroaki Kawamoto and Yoshiyuki Sankai, Second asian symposium on Industrial Automation and Robotics, BITECH, Bangkok, Thailand, May 17-18, 2001) discloses a motion assist device having an electromyographic potential sensor (detection unit) attached to the skin of an installer for detecting an electromyographic potential signal (body signal) generated when the muscle of the installer moves, and an actuator (drive source) for supplying assist power to the installer.

This motion assist device is characterized in that it drives an actuator such as a motor based on the detection result of the detection unit, and at the same time, controls the actuator with a computer to provide assist force (assist power) according to the consciousness of the installer. Therefore, the motion assisting device can provide the assisting force generated according to the consciousness of the installer to the installer, and can provide the assisting force required for the motion of the installer to the installer so as to be interlocked with the motion of the installer.

In addition, in the above-described motion assist device, the assist force may be generated by inputting a control signal (the control signal having a predetermined correlation with a signal obtained by amplifying the detection signal of the myoelectric potential sensor) to the drive circuit for controlling the actuator so as to satisfy the predetermined correlation with the myoelectric potential signal generated by the installer, for example.

That is, since the myoelectric potential signal and the power of the muscle of the installer have a positive correlation and the ratio of the magnitude of each other is a predetermined value, it is necessary to generate an assisting force corresponding to the myoelectric potential signal in order to satisfy the desired relationship. In other words, if the assist force provided by the motion assist device does not satisfy the predetermined relationship with the myoelectric potential signal, the assist power provided to the installer is either too large or too small, which is likely to significantly deteriorate the convenience of use for the user.

The myoelectric potential signal generated by the installer is a very weak electric signal, and the proportional relationship between the myoelectric potential signal of each person and the muscle strength generated by the myoelectric signal is different, and the electrical resistance value of the skin is not fixed even in the same person due to the daily physical condition, and therefore, the myoelectric potential signal and the muscle strength generated by the myoelectric potential signal are not fixed in many cases. Therefore, in the above-described motion assist device, in order to add a predetermined coefficient to the control signal to calibrate the control amount supplied to the actuator, it is necessary to have a so-called calibration device. Specifically, when the motion assist device is mounted on the installer, it is necessary to have a calibration device that can perform calibration based on a coefficient so as to correspond the myoelectric potential signal and the assisting force to a predetermined relationship. This calibration device is configured to first acquire a myoelectric potential signal when a predetermined amount of load is applied to the wearer, and then perform calibration by changing the above-mentioned coefficient in accordance with the correspondence between the load and the myoelectric potential signal.

In this calibration apparatus, the load applied to the installer is changed stepwise, and when the installer generates a muscle force in order to resist the load of each stage, the myoelectric potential signal and the auxiliary power may be associated with a predetermined relationship according to the association between the load of each stage and the myoelectric potential signal.

As a method of changing the load applied to the body of the installer in a stepwise manner, a method of preparing hammers of different weights in advance and changing the hammers for each detection of the surface myoelectric potential may be considered, or a method of connecting a coil spring to the leg of the installer and changing the amount of extension of the coil spring in a stepwise manner may be considered.

The motion assist device having the calibration device using these methods can accurately correspond the myoelectric potential signal and the assist power to a predetermined relationship as needed, and therefore, it is possible to prevent the occurrence of an excessive or insufficient assist force to be given to the installer.

In the above-described movement assistance device, as described above, the myoelectric potential sensor for detecting the myoelectric signal is directly attached to the skin of the wearer and detects the surface myoelectric potential through the skin. Therefore, even if the installer is the same person, if the myoelectric potential sensor is attached at a different position or the physical condition changes, the resistance value will be different or changed, and the detected myoelectric potential signal will be non-uniform, so that the above calibration is required each time the installer installs the myoelectric potential sensor. Therefore, in the above calibration method, each time the motion assist device is attached to the installer, it is necessary to exchange the hammers having different weights a plurality of times, or attach the coil spring to the installer and change the amount of extension of the coil spring in stages, and these troublesome works are imposed on the installer.

Therefore, the conventional calibration method has a great problem that the work required by one installer for the purpose of calibration is very troublesome, the time taken to complete the calibration work is long, and an excessive burden is imposed on an installer who has weak muscle strength. For this reason, the motion assist device has a great limitation in practical use, popularization, and the like.

Disclosure of Invention

In order to solve the above-described problems, an object of the present invention is to reduce the burden on an installer in performing calibration by calibrating parameters.

In order to achieve the above object, the present invention adopts the following technical means.

The invention provides a mounting type action auxiliary device, which comprises: a detection unit for detecting a body signal generated by the installer; an action assisting unit having a driving source for supplying power to an installer; and a control unit for controlling the driving source to generate the auxiliary power corresponding to the detection signal detected by the detection unit. The mounting type motion assisting device is characterized by further comprising a calibration unit which sets a calibration value according to a body signal detected by the detection device, wherein the body signal corresponds to the driving force provided by the driving source as the load.

The present invention also provides a mount-type motion assist device, including: a detection unit for detecting a body signal generated by the installer; an action assisting unit having a driving source for supplying power to an installer; and a control unit for controlling the driving source to generate the auxiliary power corresponding to the detection signal detected by the detection unit. The mounting type motion assisting device is characterized by further comprising a load generating unit and a calibration value setting unit, wherein the load generating unit is used for providing an external load, and the external load is a preset driving force provided by the driving source when the motion assisting unit is mounted on a body of a mounting person; the calibration value setting means generates a parameter necessary for the control means to execute arithmetic processing based on the body signal generated against the driving force supplied from the load generation means and detected by the detection means, and sets the parameter as a calibration value specific to the installer.

In the above invention, the calibration unit has a database for storing data of a correspondence relationship between the detection signal detected by the detection unit and the control signal for controlling the drive source, and the control unit calibrates the control signal stored in the database based on the calibration value set by the calibration value setting unit.

In the above invention, the detecting unit is used in a state of being attached to the skin of the installer, and detects the myoelectric potential of the installer as the body signal.

In the above invention, the motion assisting unit includes a belt, a right foot assisting unit and a left foot assisting unit, the right foot assisting unit is provided at a lower right side of the belt, and the left foot assisting unit is provided at a lower left side of the belt. The right foot assisting part and the left foot assisting part are respectively provided with a first support, a second support, a third support, a fourth support, a first joint and a second joint, the first support extends downwards from the waistband to support the waistband, the second support extends downwards from the first support, the third support extends downwards from the second support, the fourth support is arranged at the lower end of the third support and bears the bottom of the foot of an installer, the first joint is located between the lower end of the first support and the upper end of the second support, and the second joint is located between the lower end of the second support and the upper end of the third support.

In the above invention, the first joint is provided at a height corresponding to a crotch joint of the installer, and the second joint is provided at a height corresponding to a knee joint of the installer.

In the above invention, the first joint is provided with a first drive source for transmitting a drive force to rotate the second bracket, and the second joint is provided with a second drive source for transmitting a drive force to rotate the third bracket.

In the above invention, the first and second drive sources each include an angle sensor for detecting a joint angle.

The present invention also provides a calibration device for correlating a body signal and an auxiliary power with a predetermined relationship when a motion assisting unit having a driving source for generating the auxiliary power corresponding to the body signal from an installer is installed on the installer each time, the calibration device having a first storage unit for previously storing a first correlation between the power and the body signal from the installer who installs the motion assisting unit and a second storage unit for previously storing a second correlation between the power and the body signal from the installer during execution of a predetermined basic motion, the calibration device calibrating the auxiliary power corresponding to the body signal based on the body signal from the installer during the basic motion and the second correlation each time the motion assisting unit is installed on the installer, so as to satisfy the above-described first correspondence relationship.

In the above invention, the first correspondence relationship is a relationship in which the dynamic force and the physical signal have a positive correlation, and the second correspondence relationship is a relationship in which a change in the physical signal and a change in the dynamic force of the basic motion are correlated.

The present invention also provides a calibration program that enables a computer to perform calibration for associating a body signal and an auxiliary power with a predetermined relationship each time a motion assisting unit having a drive source that generates the auxiliary power in accordance with the body signal issued by an installer is installed on the installer, the calibration program including a first program and a second program, the first program being capable of causing the computer to perform operations for storing in advance a first storage unit a first correspondence relationship between the power and the body signal issued by the installer who has installed the motion assisting unit, and for storing in a second storage unit a second correspondence relationship between the power and the body signal generated during the installer's execution of a predetermined basic motion; the second program may cause the computer to execute an operation of, when the motion assisting unit is attached to the body of the installer, calibrating the assist power according to the body signal generated when the basic motion of the installer is executed and the second correspondence relationship stored in the second storing unit so as to satisfy the first correspondence relationship stored in the first storing unit.

According to the present invention, the detection unit detects a body signal corresponding to the driving force provided by the driving source as the load, and sets the calibration value based on the body signal detected, so that the calibration can be automatically performed by mounting the hammer as the load on the body of the installer or using the coil spring without using the hammer, which is a troublesome work, and using the driving force generated by the driving source provided in the motion assisting unit as the load. Therefore, the work and time required for calibration can be significantly reduced, and the practical use and the popularization of the attachment type motion assisting device can be further promoted.

In addition, since the extra burden imposed on the installer of the decline of the muscle strength during the calibration is eliminated, when the motion assisting unit is installed on the installer, the installer can automatically perform the calibration by only a simple operation, and the calibration value corresponding to the state of the installer can be set to provide the driving force corresponding to the myoelectric potential signal of the installer so as to be interlocked with the motion of the installer.

Therefore, when the calibration is performed, the assist force according to the consciousness of the installer is provided by the drive source, and the assist force is not too large or too small, and the movement of the installer can be stably assisted, so that the reliability of the installation type assisting device can be further improved.

In particular, when the installer is as a novice, though feeling hard to operate the motion assisting unit as he/she wants, the installer can also carry out the calibration with caution. Thus, the installer may avoid physical handicaps of the installer by performing a calibration without requiring special operations, even for disabled persons with impaired mobility, so as to compensate for physical weakness of the installer.

Drawings

Fig. 1 is a block diagram showing a control system applied to an embodiment of the motion assist device of the present invention.

Fig. 2 is a perspective view of an attached state of the attached motion assist device according to the embodiment of the present invention as viewed from the front.

Fig. 3 is a perspective view of an attached state of the attached motion assist device according to the embodiment of the present invention, as viewed from the rear.

Fig. 4 shows a left side view of the motion assisting unit 18.

Fig. 5 shows a rear view of the motion assisting unit 18.

Fig. 6 is a block diagram showing components constituting the motion assist device 10.

Fig. 7 is a schematic diagram showing an example of each operation job and each operation stage.

Fig. 8 shows a schematic diagram of a pattern of the calibration data base 148.

Fig. 9 is a schematic diagram showing the operation processes of the operation phases a1 to a4 as an example of the operation job.

Fig. 10 is a schematic diagram showing the detection positions of the surface myoelectric potentials e1 to e4, in which (a) is a schematic diagram showing the leg portion viewed from the front, and (B) is a schematic diagram showing the leg portion viewed from the rear.

Fig. 11 is a schematic diagram showing the detection positions of the surface myoelectric potentials e1 to e4, in which (a) shows a side view of the leg when the crotch joint is bent in the arrow direction, and (B) shows a side view of the leg when the knee joint is bent in the arrow direction.

Fig. 12 is a schematic view showing a state of knee joint flexor muscles of the installer 12 who installs the motion assisting unit 18.

Fig. 13 shows a graph of input power and virtual power corresponding to the extensor muscles of the right crotch joint.

Fig. 14 shows curves corresponding to the input power and the virtual power of the right crotch joint flexor.

Fig. 15 is a graph showing the difference between the superficial myoelectric potential and the virtual dynamic force when the installer 12 performs the same action as the standard predetermined action.

Fig. 16 is a graph showing the change in joint angle of the crotch joint and the change in joint angle of the knee joint when the flexion and extension movements are performed.

Fig. 17 is a graph showing the virtual power of the bending motion of the crotch joint, the virtual power of the extending motion of the crotch joint, the virtual power of the bending motion of the knee joint, and the virtual power of the extending motion of the knee joint when the flexion and extension motions are performed.

Fig. 18 is a graph showing the surface myoelectric potential of the bending motion of the crotch joint, the standard virtual power of the bending motion of the crotch joint, and the estimated power of the stretching motion of the crotch joint when performing the flexion and extension motions.

Fig. 19 is a graph showing the surface myoelectric potential of the stretching operation of the crotch joint, the standard virtual power of the stretching operation of the crotch joint, and the estimated power of the bending operation of the crotch joint when the flexion and extension operations are performed.

Fig. 20 is a flowchart for explaining the execution of the main control process by the control device 100.

Fig. 21 is a flowchart showing control for performing initial calibration for initial setting in a stationary state.

Fig. 22 is a flowchart showing control of the recalibration setting based on one operation.

Fig. 23 is a flowchart showing control for performing calibration according to a predetermined standard operation.

Detailed Description

The preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

Example 1

Fig. 1 is a block diagram showing a control system applied to an embodiment of the motion assist device of the present invention.

As shown in fig. 1, the control system of the motion assist device 10 includes: a drive source 140 for providing assistance to an installer; a physical phenomenon detection unit 142 for detecting a joint angle (physical phenomenon) corresponding to the motion of the installer 12; a body signal detecting unit 144 for detecting a myoelectric potential (body signal) corresponding to a muscle force generated by the installer 12.

The data holding unit 146 has a calibration database 148 and a command signal database 150, and the calibration database 148 is used to calibrate the parameters of the command signal (control signal) according to the detection sensitivity of the myoelectric potential (body signal) corresponding to the muscle force generated by the installer 12. As will be described later, the calibration database 148 further includes a first storage area (first storage means) for previously storing a first correspondence relationship between the power (muscle strength) and the body signal (myoelectric potential signal) generated by the installer 12 who has the motion assistance unit 18 (see fig. 2 and 3) installed therein, and a second storage area (second storage means) for previously storing a second correspondence relationship between the power (muscle strength) and the body signal (myoelectric potential signal) generated by the installer 12 during the execution of the predetermined basic motion.

The joint angles (θ knee, θ hip) detected by the physical phenomenon detection means 142 and the myoelectric potential signals (emgkne, EMGhip) detected by the body signal detection unit 144 are input into the calibration database 148 and the command signal database 150.

The control device 100 includes an operation stage identifying unit 152, a difference deriving unit 154, a parameter calibration unit 156, a control unit 160, a calibration control unit 162, and a load generating unit 164. Each time the movement assisting unit 18 is attached to the installer 12, the calibration control unit 162 calibrates the assisting power corresponding to the body signal to satisfy the first corresponding relationship, based on the body signal generated by the installer 12 during the basic movement and the second corresponding relationship.

That is, when the installer 12 mounts the motion assist unit 18 and turns on the power switch, the calibration control unit 162 performs the calibration control process, and the load generation unit 164 supplies the driving force generated by the driving source 140 to the installer 12 in stages as a load (input power) so that the installer 12 generates a muscle force against the driving force.

Then, the installer 12 to which the driving force generated by the driving source 140 is applied performs a predetermined calibration operation (for example, operation A: an operation from a sitting state to a standing state) determined in advance, and causes the skeletal muscle to develop muscle strength. In this way, when the above calibration operation is performed, the physical phenomenon detection unit 142 detects the joint angle, and the body signal detection unit 144 detects the myoelectric signal.

Then, the operation phase determination means 152 determines the operation phase of the calibration operation work of the installer 12 by comparing the joint angle detected by the physical phenomenon detection means 142 with the joint angle stored in the calibration database 148.

Further, from the start of the calibration control process, the difference deriving unit 154 compares the load (input power) of the drive source 140 supplied from the load generating unit 164 and the muscle strength (estimated power) according to the myoelectric potential signal (actual measurement value) detected by the body signal detecting unit 144, obtains the difference between the two, and obtains the second correspondence relationship.

Further, the parameter calibration means 156 calibrates the parameter K so as to satisfy the first correspondence relationship based on the difference between the load (input power) and the muscle strength (estimated power) calculated by the difference deriving means 154 at the operation stage identified by the operation stage identifying means 152. When there is no difference between the input power generated by the driving source 140 and the muscle strength corresponding to the myoelectric potential signal (measured value) detected by the body signal detecting unit 144, which is provided by the load generating unit 164, the standard parameter is not calibrated. However, when there is a difference between the input power generated by the driving source 140 and the muscle strength corresponding to the myoelectric potential signal (measured value) detected by the body signal detecting unit 144, which is supplied from the load generating unit 164, the parameter K is calibrated so that the two coincide. At this time, the calibration parameter K' is set so that the input power and the estimated power are equal.

Then, the calibration control unit 162 sets the parameter calibrated by the parameter calibration unit 156 as the parameter of the installer 12, and performs calibration for the next operation stage.

In this way, by controlling the drive source 140 using the parameters set by calibration so as to generate the assist force corresponding to the body signal detected by the body signal detecting unit 144, the muscle strength and the assist force can be controlled so as to be maintained at a predetermined ratio of, for example, 1: 1, without being restricted by the state (skin resistance value) of the installer 12 that day and the difference in the installation position of the body signal detecting unit 144.

In the control unit 160, the joint angle (θ knee, θ hip) detected by the physical phenomenon detection unit 142 and the myoelectric potential signal (emgkne, EMGhip) detected by the body signal detection unit 144 are supplied at all times, the assist force generated by the drive source in each operation stage corresponding to the joint angle and the myoelectric potential signal is calculated using the calibration data K' set by the calibration control unit 162, and the command signal obtained from the calculation result is supplied to the power amplification unit 158.

An embodiment of a specific configuration of the attachment type motion assisting apparatus 10 of the present invention will be described in detail below.

Fig. 2 is a perspective view of an attached state of the attached motion assist device according to the embodiment of the present invention as viewed from the front. Fig. 3 is a perspective view of an attached state of the attached motion assist device according to the embodiment of the present invention as viewed from the rear.

As shown in fig. 2 and 3, the motion assist device 10 is a device for assisting a walking motion of a person who is difficult to walk with his or her own strength, such as a person with lower limb motor dysfunction who is unable to walk freely due to a decrease in muscle strength of the skeletal muscle, or a patient who is performing rehabilitation functions, and first detects a body signal (surface myoelectric potential) generated when muscle strength is generated based on a signal of the brain, and then operates by providing a driving force from an actuator based on the detected body signal.

Therefore, the operation assisting device 10 is distinct from a so-called teaching and playback robot, which is configured by controlling a robot hand by a computer based on data input in advance. The motion assisting device 10 is also called a "Robot clothing" (Robot unit) or a "Power clothing" (Power unit).

When the installer 12 who installs the movement assisting device 10 performs the walking movement according to his or her own consciousness, the movement assisting device 10 provides the driving power corresponding to the body signal generated by the installer 12 at that time as the assisting force, so that the user can walk with a force half of the muscle force required for normal walking, for example. Therefore, the installer 12 can walk while supporting the body weight of the whole body by the resultant force of the muscle force of the installer and the driving power generated by the actuator (in the present embodiment, the electric driving motor).

In this case, it is necessary to control the motion assisting device 10 so that the assist force provided in accordance with the center of gravity shift when the walking motion is performed reflects the consciousness of the installer 10 as described later. Therefore, it is necessary to control the actuator of the motion assist device 10 so as not to provide a load against the awareness of the installer 12 and to prevent the installer 12 from interfering with the motion.

The movement assisting device 10 can assist the walking movement, and can assist the installer 12 in the movement from the sitting state to the standing state, or in the movement from the standing state to the sitting state to the chair. Still further, the maneuver assisting device 10 may also assist the installer 12 in moving up and down stairs. In particular, when the muscle strength of the installer 10 is weak, it is difficult to perform the climbing operation and the rising operation from the chair, but the installer 12 who installs the motion assist device 10 can be given the driving power according to his or her own consciousness, and can perform these operations without depending on the muscle strength that he or she has weakened.

An example of the structure of the motion assistance device 10 will be described below.

As shown in fig. 2 and 3, the motion assist device 10 is a motion assist device in which an actuator (corresponding to the drive source 140) is provided in the motion assist unit 18 attached to the body of the installer 10. As an actuator, it has: a right leg driving motor 20 which is located at the position of the right crotch joint of the installer 12; a left leg drive motor 22 located at the left crotch joint of the installer 12; a right knee drive motor 24 located at the position of the right knee joint of the installer 12; the left knee drives a motor 26, which is located at the position of the left knee joint of the installer 12. These drive motors 20, 22, 24, and 26 are drive sources constituted by servo motors whose drive forces are controlled in accordance with control signals generated by a control device, and have a speed reduction mechanism (not shown) capable of reducing the speed of motor rotation at a predetermined speed reduction ratio, and can provide a sufficiently large drive force even though they are small.

In addition, a belt 30 mounted on the waist of the installer 12 is provided with batteries 32, 34 as a power source for driving the motors 20, 22, 24, 26. The batteries 32 and 34 are rechargeable batteries, and are provided on the left and right sides of the installer 12, respectively, so as not to interfere with the walking motion of the installer 12.

The control box 36 attached to the back of the installer 12 is provided with a control device, a motor driver, a measuring device, a power supply circuit, and the like as described later. The lower portion of the control box 36 is supported by the belt 30, and the weight of the control box 36 is set so as not to be a burden on the installer 12.

Next, the motion assist device 10 is also provided with a myoelectric potential sensor, that is: myoelectric potential sensors 38a and 38b for detecting the surface myoelectric potential (EMGhip) of the right leg of the installer 12 when moving; myoelectric potential sensors 40a and 40b for detecting the surface myoelectric potential (EMGhip) of the left leg of the installer 12 when moving; myoelectric potential sensors 42a and 42b for detecting the surface myoelectric potential (emgkne) of the right knee of the installer 12 when moving; and myoelectric potential sensors 44a and 44b for detecting the surface myoelectric potential (EMGknee) of the left knee of the installer 12 when moving.

These myoelectric potential sensors 38a, 38b, 40a, 40b, 42a, 42b, 44a, and 44b are all for detecting the surface myoelectric potential when the skeletal muscle generates muscle force, and have electrodes (not shown) for detecting a weak electric potential emitted from the skeletal muscle. In the present embodiment, the respective myoelectric potential sensors 38a, 38b, 40a, 40b, 42a, 42b, 44a, and 44b are attached to the skin of the installer 12 by adhesive tapes covering the peripheries of the electrodes.

In the human body, acetylcholine of synaptic transmission substance is discharged on the muscle surface of the skeletal muscle according to the brain's command, and thus ion permeability of the sarcolemma is changed to generate an activity potential (EMG). Due to the generation of the action potential, the muscle fibers contract, and further, muscle strength is generated. Therefore, the muscle force generated during the walking motion can be estimated by detecting the muscle potential of the skeletal muscle, and the assist force required for the walking motion can be obtained from the virtual power obtained from the estimated muscle force.

When a protein called Actin (Actin) and Myosin (Myosin) is supplied to blood, the muscle stretches, but muscle strength is generated by contraction of the muscle. Therefore, at a joint where two bones are rotatably connected to each other, that is, between the two bones, there are flexors that generate a force in the direction of bending of the joint and extensors that generate a force in the direction of extending the joint.

Thus, in the human body, there are several muscles for generating motion of the legs from the waist downward, including the loin muscles of the intestines for raising the legs forward, the gluteus maximus for contracting the legs, the quadriceps femoris for extending the knees, and the biceps femoris for bending the knees, etc.

The myoelectric potential sensors 38a and 40a are attached to the front side of the thigh root of the wearer 12, and detect the surface myoelectric potential of the intestine and lumbar muscles to measure the myoelectric potential corresponding to the muscle strength when the leg is lifted forward.

The myoelectric potential sensors 38b and 40b are attached to the hip of the wearer 12, and detect the surface myoelectric potential of the gluteus maximus to measure the myoelectric potential corresponding to, for example, a backward kick force or a muscle force when climbing stairs.

The myoelectric potential sensors 42a and 44a are attached to the upper front side of the knee of the installer 12, and detect the surface myoelectric potential of the quadriceps femoris to measure the myoelectric potential corresponding to the muscle strength extending forward below the knee.

The muscle sensors 42b and 44b are attached to the upper rear side of the knee of the installer 12, and detect the surface myoelectric potential of the quadriceps femoris to measure the myoelectric potential corresponding to the muscle strength to retract the knee below to the rear.

Therefore, the movement assisting device 10 is configured to first obtain the drive currents to be supplied to the 4 drive motors 20, 22, 24, and 26 from the surface myoelectric potentials detected by the myoelectric potential sensors 38a, 38b, 40a, 40b, 42a, 42b, 44a, and 44b, and then drive the motors 20, 22, 24, and 26 with the drive currents to provide the assisting force to the installer 12, thereby assisting the installer 12 in performing the walking movement.

In addition, in order to smoothly perform the center of gravity shifting in the walking motion, it is necessary to detect the load on the sole. Therefore, reaction force sensors 50a, 50b, 52a, 52b (shown by broken lines in fig. 2 and 3) are provided on the soles of the left and right feet of the installer 12.

The reaction force sensor 50a detects a reaction force corresponding to a load on the front side of the right foot, and the reaction force sensor 50b detects a reaction force corresponding to a load on the rear side of the right foot. The reaction force sensor 52a detects a reaction force corresponding to a load on the front side of the left foot, and the reaction force sensor 52b detects a reaction force corresponding to a load on the rear side of the left foot. Each of the reaction force sensors 50a, 50b, 52a, and 52b is configured by, for example, a piezoelectric sensor or the like that outputs a voltage according to an applied load, and is capable of detecting a change in load when the body weight is moved and whether or not the sole of the wearer 12 is in contact with the floor surface.

The configuration of the motion assisting unit 18 will be described below with reference to fig. 4 and 5.

Fig. 4 is a left side view of the action assisting unit 18. Fig. 5 is a rear view of the action assisting unit 18.

As shown in fig. 4 and 5, the motion assisting unit 18 includes: a waist belt 30 disposed between the waist of the installer 12; a right foot assisting section 54 provided at a lower right portion of the belt 30; and a left foot assisting section 55 provided on the lower left of the waist belt 30.

The right foot assisting portion 54 and the left foot assisting portion 55 are symmetrically arranged, and include: a first bracket 56 extending downward to support the waist belt 30; a second bracket 58 extending downwardly from the first bracket 56 and disposed along the outer thigh of the wearer 12; a third brace 60 extending downwardly from the second brace 58 and disposed along the lateral side of the lower leg of the wearer 12; a fourth cradle 62 for carrying the sole of the foot (or sole if the shoe is worn) of the wearer 12.

Between the lower end of the first bracket 56 and the upper end of the second bracket 58, there is a first joint 64 having a hinged configuration to rotatably connect the first bracket 56 and the second bracket 58 together. The first joint 64 is disposed at the same height as the crotch joint, the first bracket 56 is connected to the support side of the first joint 56, and the second bracket 58 is connected to the rotation side of the first joint 64.

In addition, a second joint 66 having a hinge structure is provided between the lower end of the second bracket 58 and the upper end of the third bracket 60 to rotatably couple the second bracket 58 and the third bracket 60 together. The second joint 66 is disposed at a position as high as the knee joint, the second bracket 58 is connected to the support side of the second joint 66, and the third bracket 60 is connected to the rotation side of the second joint 66.

Thus, the second bracket 58 and the third bracket 60 are arranged to perform a rocking motion with respect to the first bracket 56 fixed to the waist belt 30, with the first joint 64 and the second joint 66 as rotation fulcrums. That is, the second bracket 58 and the third bracket 60 are configured to be able to do the same action as the legs of the installer 12.

Further, a motor bracket 68 is provided on the support side of the first joint 64 and the second joint 66. The motor bracket 68 has a motor support portion 68a protruding horizontally outward, and the drive motors 20, 22, 24, 26 are vertically disposed on the motor support portion 68 a. Therefore, the drive motors 20, 22, 24, and 26 are not provided so as to protrude in the lateral direction, and are not likely to contact surrounding obstacles during walking.

The first joint 64 and the second joint 66 are configured such that the rotation shafts of the drive motors 20, 22, 24, and 26 transmit drive power to the second bracket 58 and the third bracket 60 on the driven side through gears.

In addition, the drive motors 20, 22, 24, and 26 are also provided with sensors 70, 72, 74, and 76 (equivalent to the physical phenomenon detection unit 142) for detecting joint angles. The angle sensors 70, 72, 74, and 76 may be constituted by, for example, a rotary encoder or the like that increments a pulse number proportional to the joint angle of the first joint 64 and the second joint 66, and output an electric signal corresponding to the pulse number obtained from the joint angle as an output amount of the sensor.

The angle sensors 70 and 72 are used to detect a rotation angle between the first bracket 56 and the second bracket 58, which corresponds to a joint angle (θ hip) of the crotch joint of the installer 12. In addition, the angle sensors 74 and 76 are used to detect a rotation angle between the lower end of the second bracket 59 and the third bracket 60, which corresponds to a joint angle (θ knee) of the knee joint of the installer 12.

Additionally, the first joint 64 and the second joint 66 are only configured to rotate within the range of possible rotation of the crotch joint and the knee joint of the installer 12, and a stop mechanism (not shown) is provided internally to prevent over-range motion of the crotch joint and the knee joint provided to the installer 12.

The second bracket 58 has a first securing strap 78 thereon for securing it to the thigh of the installer 12. In addition, third brace 60 has a second strap 80 for securing it under the knee of installer 12. Thus, the driving power provided by the driving motors 20, 22, 24 and 26 is transmitted to the second and third brackets 58 and 60 via the gears, and then transmitted to the legs of the installer 12 as an assisting force via the first and second fixing belts 78 and 80.

In addition, the fourth bracket 62 is rotatably connected to the lower end of the third bracket 60 by a shaft 82. The fourth bracket 62 is also provided at a lower end thereof with a heel receiving portion 84 for receiving a heel portion of the sole of the wearer 12. The second bracket 58 and the third bracket 60 are adjustable in length in the axial direction by screws, and can be adjusted to an appropriate length according to the leg length of the installer 12.

The brackets 56, 58, 60, and 64 are each formed of metal and are capable of supporting the weight of the batteries 32 and 34, the control box 36, and the motion assist unit 18 provided on the belt 30. That is, the movement assisting device 10 is designed so as not to apply the weight of the movement assisting unit 18 and the like to the installer 12, and can be attached to the installer 12 with weak muscle strength without applying an excessive load to the installer 12.

Fig. 6 is a block diagram showing each unit constituting the motion assist device 10.

As shown in fig. 6, the batteries 32 and 34 are used to supply power to the power supply circuit 86, and the power supply circuit 86 converts the power to a predetermined voltage and supplies the voltage to the input-output interface 88. The charge amounts of the batteries 32 and 34 are monitored by the battery charge notification unit 90, and when the battery capacity is lower than a preset remaining capacity, the battery charge notification unit 90 notifies the installer 12 of the replacement of the battery or the need for charging.

First to fourth motor drivers 92 to 95 for driving the motors 20, 22, 24 and 26 amplify the driving voltage corresponding to the control signal generated by the control device 100 via the input/output interface 88 and output the amplified driving voltage to the respective driving motors 20, 22, 24 and 26.

The detection signals of the surface myoelectric potential output from the myoelectric potential sensors 38a, 38b, 40a, 40b, 42a, 42b, 44a, and 44b are amplified by first to eighth differential amplifiers 101 to 108 (corresponding to the power amplification unit 158), converted into digital signals by an a/D converter, and then input to the control device 100 via the input/output interface 88. In addition, the myoelectric potential emitted by the muscle is very slightTherefore, in the first to eighth differential amplifiers 101 to 108, for example, 10 μ V is necessary to amplify the myoelectric potential of 30 μ V to about 3V which can be discriminated by a computer⁵Doubling the amplification rate of 100 dB.

The angle detection signals output from the angle sensors 70, 72, 74, and 76 are input to the first to fourth angle detection units 111 to 114, respectively. The first to fourth angle detection units 111 to 114 convert the number of pulses detected by the rotary encoder into angle data corresponding to an angle, and the detected angle data is input to the control device 100 via the input/output interface 88.

Reaction force detection signals output from the reaction force sensors 50a, 50b, 52a, and 52b are input to the first to fourth reaction force detection units 121 to 124, respectively. The first to fourth reaction force detecting units 121 to 124 convert the voltage detected by the piezoelectric sensor into a Digital Value (Digital Value) corresponding to the load, and the detected reaction force data is input to the control device 100 via the input/output interface 88.

The storage unit 130 (corresponding to the data storage unit 146) is a storage unit that stores each data, and includes a database storage field 130A and a control program storage field 130B, the database storage field 130A stores control data in units of operation phases set in each operation mode such as a standing operation, a walking operation, and a sitting operation, and the control program storage field 130B stores a control program for controlling each data.

In this embodiment, the database storage area 130A includes a calibration database 148 and a command signal database 150. In addition, as shown in fig. 8, the calibration database 148 stores the muscle strength (power) e of the installer 12 who installs the motion aid installer 18_A1And a body signal E_A1(t.) the first correspondence, and a reference parameter K_A1.... In addition, the first correspondence relationship is the muscle strength e_A1And a body signal E_A1(t.) is proportional and has a positive correlation.

In addition, the calibration data base 148 also holdsThe muscle force (power) e generated by the installer 12 during the predetermined basic movement_A1And a body signal E_A1(t.) and a calibration parameter K'_A1. The second relationship refers to the body signal E of the basic motion_A1Change in (t.) and muscle strength e_A1(t.) in.

The control data output from the control device 100 is output to the data output unit 132 or the communication unit 134 via the input/output interface 88, and may be displayed on a display (not shown), or may be transmitted between computers for data monitoring (not shown) by data communication, for example.

The control device 100 further includes an autonomous control system that generates a command signal for causing the installer 12 to generate a power corresponding to a certain operation stage in the operation pattern of the installer 12 identified by comparing the joint angles detected by the angle sensors 70, 72, and 76 with the joint angles of the standard parameters.

The control device 100 further includes a load generation unit 100D, a calibration value setting unit 100E (corresponding to the parameter calibration unit 156), and a calibration control unit 100F. The load generation unit 100D is for supplying the driving force generated by the driving motors (driving sources) 20, 22, 24, 26 to the installer 12 as an external load when the motion assist unit 18 is installed on the installer 12; the calibration value setting unit 100E is configured to set a calibration value, and the setting process is as follows: first, a body signal emitted against the above-described driving force supplied is detected by the myoelectric potential sensors (detecting units) 38a, 38b, 40A, 40b, 42a, 42b, 44a, 44b, and then a parameter for performing calculation by the autonomic control unit 100A (for example, proportional gain in proportional control) is generated based on this detected body signal, and this parameter is set as a calibration value inherent to the installer 18; the calibration control unit 100F is configured to set the calibrated parameters as the intrinsic parameters to the installer 12 by appropriately controlling the operations of the calibration value setting unit 100E and the like.

As the calibration in this embodiment, for example, initial setting calibration performed when the motion assisting unit 18 is used is first attached, or resetting calibration performed each time the motion assisting unit 18 is attached after the initial setting calibration is performed may be used.

The initial setting calibration is a calibration value setting process that the installer 12 performs in a stationary state using a predetermined posture as described later.

The reset calibration is a calibration value setting process that the installer 12 executes using a predetermined basic operation as described later, and may be, for example, calibration in a stationary state in which the installer 12 executes a calibration value updating process using a generated muscle force in the stationary state, or calibration based on one operation in which the installer 12 executes a calibration value updating process by performing an operation of once moving the knees from the flexed state to the extended state in the standing state.

In the calibration, the load applied to the installer 12 at the beginning is set to be small, and the body signal generated against the load is detected while the load is gradually increased by controlling the drive motors 20, 22, 24, and 26 as the calibration operation is performed. In the mounting-type motion assist device 10 of the present embodiment, one of the two types of calibration may be selected, one of which is calibration in a stationary state as initial setting calibration, and the other of which is calibration based on one motion as resetting calibration performed every time of mounting.

Next, the operation of the installer 12 when performing calibration will be described with reference to fig. 7 to 9. Fig. 7 is a schematic diagram showing an example of each operation job and operation phase stored in the database.

As shown in fig. 7, the operation jobs stored in the storage unit 130 for classifying the operations of the mounter 12 include, for example: an action operation A having standing up action data for moving from a sitting posture to a standing posture; an operation B having walking motion data for walking motion of the standing installer 12; an action task C having sitting action data for moving from a standing posture to a sitting posture; and an operation D having stair climbing operation data for climbing stairs in a standing state.

In addition, in each operation, a plurality of operation stage data defining a minimum operation unit are set, and for example, in the operation B of the walking operation, there are provided: an action phase B1 having action data when the legs are put together; an action phase B2 with action data when the right leg is taken forward; an action phase B3 having action data when the left leg is taken forward and put together with the right leg; motion phase B4 with motion data for the left leg taken forward.

Fig. 8 is a schematic diagram showing a mode of the calibration data base 148.

As shown in FIG. 8, the calibration data base 148 stores the surface myoelectric potential e_A1(t.) and a reference parameter K corresponding to myoelectric potential_A1.., the surface myoelectric potential is detected in each operation stage obtained by dividing each operation A, B.

In the present embodiment, the installer 12 who installs the motion assisting unit 18 performs a predetermined calibration motion determined in advance. Here, for example, it is assumed that the installer 12 shown in fig. 9 first performs the reference operation from the sitting posture to the standing posture (operation stages a1 to a4), and then performs the sitting operation (operation stages a4 to a 1).

The calibration principle of the body signal detecting unit 144 will be described in detail below, and the body signal detecting unit 144 is used to detect the myoelectric potential corresponding to the muscle strength of the installer 12.

The relationship between surface muscle potential and the muscle force exerted by the installer 12 when the installer is performing a static motion is generally approximately linear. Therefore, the present invention has developed an estimation method for estimating the power of the installer 12 from the measured surface myoelectric potential based on the expressions (1) and (2). The estimated power is referred to as "virtual power".

τ_hip＝K₁e₁-K₂e₂ (1)

τ_knee＝K₄e₄-K₃e₃ (2)

In the formulae (1) and (2), τ_hipIs the virtual power of the crotch joint, tau_kneeIs the virtual power of the knee joint, e₁～e₄Is the surface myoelectric potential of muscle generation, K₁～K₄Is a parameter. The crotch joint and knee joint of the installer 12 act in the balance of muscular flexion and extension. As shown in (A) and (B) of FIG. 10 and (A) and (B) of FIG. 11, e₁Is the surface myoelectric potential of the rectus femoris muscle of the thigh e₂Is the surface myoelectric potential of the gluteus muscles e₃Is the superficial myoelectric potential of the medial musculus major, e₄Is the superficial myoelectric potential of the biceps femoris muscle of the thigh.

In calculating the virtual power, a value filtered by a digital filter is used in consideration of the influence of clutter and the like. In this example, the obtained value having passed through the low-pass filter is used as the surface muscle potential value.

In the calibration of the control system for detecting the surface muscle potential, each parameter K of equation (3) is obtained by equations (1) and (2), and equation (3) is used to calculate the virtual power of each muscle.

τ＝Ke (3)

That is, in the calibration of the present embodiment, the value of the parameter K in equation (3) is obtained so that the value of the surface myoelectric potential of the target muscle when a force of 1Nm is generated becomes 1, and the value is updated.

As described above, in the present embodiment, regardless of whether the initial setting calibration or the resetting calibration is performed, the myoelectric potential sensors 38a, 38b, 40a, 40b, 42a, 42b, 44a, and 44b are detected, and the value of the parameter K is calibrated using the result of the detection.

The reset calibration will be described below. As this calibration movement, for example, a movement of moving the knee from the flexed condition to the extended condition may be performed by the installer 12 in the sitting condition. The resetting calibration of the present invention can not only reduce the burden on the installer 12, but also complete the calibration in a short time.

Fig. 12 is a schematic diagram showing a flexor state of the knee joint of the installer 12 who installs the motion assisting unit 18.

As shown in fig. 12, the drive motors 20, 22, 24, 26 apply input power τ as a load to the knee joint of the installer 12 who installs the motion assisting unit 18_m. The installer 12 generates a resistive input power tau against this input power_mAnd keep the knee joint in a stationary state. At this time, it can be said that the input rotational force τ provided by the drive motors 20, 22, 24, 26_mAnd muscle force τ generated by installer 12_hAre equal.

Therefore, the relationship of the equation (4) is established.

τ_m(t)＝τ_h(t) (4)

Because the muscle force generated by the installer 12 can be represented by equation (3), namely:

τ_h＝Ke (5)

therefore, equation (4) can be rewritten as:

τ_m＝Ke (6)

next, a procedure of performing the initial setting calibration in the above-described stationary state will be described.

The calibration of the initial setting of the static state can be performed as follows.

(step 1) detection of the installer 12 generating a driving force (rotational force τ) against the drive motors 20, 22, 24, 26_m) Surface myoelectric potential at muscle force ofe。

(step 2) applying a least square method from the detected surface myoelectric potential and the input torque τ at that time_mThen, a parameter K for satisfying the equation (6) is obtained.

The formula for calculating the parameter K by applying the least square method is shown as the formula (7).

K＝∑τ_m(t)e(t)/∑e²(t) (7)

Therefore, for example, the parameter K can be obtained so that the surface myoelectric potential when the installer 12 bends the knee joint to about 90 degrees and sits down in a state where the force of 1Nm is generated in a stationary state becomes 1, as shown in fig. 12. In this stationary state, the drive motors 20, 22, 24, 26 drive the driving force (power τ)_m) As a load (input power) is provided to the installer 12 in stages, whereas the installer 12 generates a muscle force against the driving force, thus maintaining the static state.

The following describes a procedure of resetting calibration for performing a predetermined standard operation.

The reset calibration based on one motion can be performed as follows.

(step 1) the installer 12 rotates the knee joint so that the angle of the knee changes from 90 degrees to 180 degrees, and then returns the knee joint to the home position so that the angle of the knee changes from 180 degrees to 90 degrees.

(step 2) the driving force (power τ m) generated by the driving motors 20, 22, 24, 26 is supplied, which corresponds to the angle of the knee joint detected by the angle sensors 74, 76.

(step 3) the surface muscle potential e of the installer 12 during the knee flexion and extension movements is detected.

The principle of the above initial setting calibration will be described below with reference to fig. 13 to 15.

For example, 8Nm, 16Nm, 24Nm, and 32Nm of power generated by the drive motors 20, 22, 24, and 26 are supplied to the installer 12 as input power τ m, and the parameter K is obtained. In this case, calibration is performed using the obtained parameter K, and a surface myoelectric potential is obtained, and a virtual power is calculated based on the surface myoelectric potential, and the result of comparison between the virtual power and the input power simultaneously input is shown in fig. 13 and 14. Fig. 13 is a schematic diagram showing input power (a) and virtual power (b) corresponding to the extensor muscles of the right crotch joint. Fig. 14 is a schematic diagram showing the input power (a) and the virtual power (b) corresponding to the flexors of the left crotch joint.

As can be seen from the input power curve (a) and the virtual power curve (b) shown in fig. 13 and the input power curve (a) and the virtual power broken line (b) shown in fig. 14, the virtual power calculated using the parameter K determined in the above-described manner substantially matches the input power applied at the same time.

As can be seen from fig. 13, the power values of the input powers generated by the drive motors 20, 22, 24, and 26 are controlled to increase in stages as time passes. That is, the driving of the motors 20, 22, 24, 26 is started by controlling to output a small driving force (input power), and the input power is controlled to gradually increase in stages while being applied in pulses at predetermined time intervals.

Therefore, the installer 12 can prevent the excessive power from being applied when the motion assistance attachment tool 18 is attached, and can gradually increase the input power value, reduce the burden on the muscle for generating the muscle force against the input power, and reduce the muscle fatigue generated during the calibration.

As can be seen from fig. 13 and 14, the same results were obtained for the left and right hip joints and the left and right knee joints. When the virtual power is calculated using the parameter K obtained as described above to generate the assist force, the same driving force of 1Nm generated by the driving motors 20, 22, 24, and 26 can be supplied to the installer 12 as the assist force with respect to the muscle force 1Nm generated by the installer 12, and the installer 12 can perform the operation by generating the muscle force half the force required for the predetermined operation.

In the present embodiment, since the installer 12 who installs the motion assisting unit 18 needs to generate a muscle force against the input power when performing calibration, it is necessary to control the driving force of the driving motors 20, 22, 24, and 26, that is, to suppress the input power so as to perform calibration without causing an excessive load on the installer 12.

That is, in the present embodiment, the installer 12 can perform the calibration of the surface myoelectric potential by performing a predetermined operation (for example, refer to fig. 9 or fig. 10) determined in advance, without imposing an excessive burden on the installer 12.

For example, if the muscle strength generated in each joint is the same in 2 predetermined movements, the virtual power obtained in the 2 predetermined movements must be the same. Therefore, the virtual power pattern of the standard operation is stored in the storage unit 130 as the standard data, and the parameter calibration process at the time of calibration can be efficiently performed.

Further, if the parameter K obtained by the installer 12 executing the calibration operation is used, the virtual power when the installer 12 executes the standard operation is assumed to be τ_i(t), and when the surface myoelectric potential is e' (t) when the same operation is performed, the relationship of the equation (8) is established.

τ_i(t)＝Ke’(t) (8)

When the surface myoelectric potential calibration is performed, as shown in fig. 15, the surface myoelectric potential (curve (a) shown by a solid line in fig. 15) when the installer 12 performs the same operation as the standard operation is detected, and the parameter K' is calculated so that the virtual power (curve (b) shown by a broken line in fig. 15) becomes the same as the input power.

Equation (9) for calculating the parameter K' using the least square method is substantially the same as equation (7) described above.

K’＝∑τ_m(t)e’(t)/∑e’²(t) (9)

Due to virtual power τ_iSince (t) is obtained by calibration using the attachment-type assist calibration device 10, the parameter K' obtained by the above-described method can be said to be obtained similarly to the calibration using the attachment-type motion assist device 10. Therefore, the installer 12 can perform the calibration method of the predetermined operation, and can provide the installer 12 with the assist force of 1Nm with respect to the muscle force of 1Nm generated by the installer 12 itself.

Next, the test results of the standard motion using the calibration of the present invention, for example, the flexion-extension motion shown in fig. 16, are shown in fig. 17 and 18.

Curve (a) shown in fig. 17 indicates the change in joint angle of the crotch joint during flexion and extension, and curve (b) shown in fig. 17 indicates the change in joint angle of the knee joint during flexion and extension.

In fig. 18, a curve (a) shows the virtual power of the bending motion of the crotch joint during the flexion and extension motions, a curve (b) shows the virtual power of the extension motion of the crotch joint during the flexion and extension motions, a curve (c) shows the virtual power of the bending motion of the knee joint during the flexion and extension motions, and a curve (d) shows the virtual power of the extension motion of the knee joint during the flexion and extension motions.

Then, the flexion and extension movements are calibrated using the standard movements, and the calibration results of the flexors and extensors of the right crotch joint as shown in fig. 18 and 19 can be obtained. In fig. 18, a curve (a) shows the surface myoelectric potential of the stretching operation of the crotch joint during the flexion and extension operations, a curve (b) shows the standard virtual power of the stretching operation of the crotch joint during the flexion and extension operations, and a curve (c) shows the estimated power of the stretching operation of the crotch joint during the flexion and extension operations. In fig. 19, curve (a) shows the surface myoelectric potential of the bending motion of the crotch joint during the flexion and extension motions, curve (b) shows the standard virtual power of the bending motion of the crotch joint during the flexion and extension motions, and curve (c) shows the estimated power of the bending motion of the crotch joint during the flexion and extension motions.

Therefore, as is clear from the curves (a) to (c) shown in fig. 18 and 19, the standard virtual power and the estimated power obtained from the parameter K' obtained by the calibration have the same amplitude waveform, and the magnitude of the estimated power associated with the flexion and extension movements and the magnitude of the virtual power obtained from the surface myoelectric potential substantially match each other.

In this way, in the present embodiment, since the installer 12 can perform the calibration of the surface myoelectric potential by performing a predetermined action, it is possible to quickly calculate the parameter K' for calculating the virtual power (in other words, the calibrated surface myoelectric potential) without imposing a large burden on the installer 12.

In the above description, the power to be given to the installer 12 as the load may be set according to the physical strength of each person, for example, the lower limit value and the upper limit value of the load may be set in advance, and the load may be adjusted appropriately at the time of calibration without imposing an excessive load on the installer 12.

Next, the steps of the main control process executed by the control device 100 will be described with reference to the flowchart shown in fig. 20.

As shown in fig. 20, in step S11 (hereinafter, the "step" is omitted), the motion assisting unit 18 is mounted on the installer 12, and upon turning on the power switch (not shown), the process proceeds to S12, and it is checked whether the operation of turning on the power switch is the first time. If the power switch is turned on for the first time in S12, the process proceeds to S13, and the initial setting mode is switched to, and the initial setting calibration process is executed in S14.

That is, in S14, the body signal corresponding to the driving force generated as the load by the drive motors 20, 22, 24, 26 is detected by the detection signal of the surface myoelectric potential output from each myoelectric potential sensor 38a, 38b, 40a, 40b, 42a, 42b, 44a, 44b, and then the calibration value is calculated from this detection signal. In S15, the voltage applied to the motor is increased by one step to increase the load. Then, the process proceeds to S16, where it is determined whether or not the load has reached the upper limit value set in advance. In S16, if the load does not reach the upper limit value set in advance, the process returns to S14, and the process from S14 to S16 is executed in a loop.

In S16, if the load reaches the upper limit value set in advance, the process proceeds to S17, where the parameter K' obtained by the above calibration is set.

At S17, the installer 12 who has installed the motion assist installation tool 18 sets a calibration value (parameter K') corresponding to the muscle strength of the installer 12 obtained by calibration in the stationary state as shown in fig. 12. That is, in S17, the parameter K is calculated as described above so that the value of the surface myoelectric potential when the installer 12 generates 1Nm of force while bending the knee joint by about 90 degrees and sitting, and while keeping still, is 1. In this first calibration, the driving force (power τ) generated by the driving motors 20, 22, 24, 26 is driven_m) While the load (input power) is imparted to the installer 12 in stages, the installer 12 generates a muscle force to resist the driving force.

In this way, the body signal generated against the driving force supplied from the driving source is detected by each myoelectric potential sensor, and a parameter for arithmetic processing is generated based on the detected signal, and this parameter is stored in the database 148 as a calibration value specific to the installer.

Thereafter, the process proceeds to S18, where the control mode is switched to the control mode in which the normal assist control process is executed. Then, in S19, the normal control mode is executed until the power switch is turned off.

In S12, if the power switch is turned on for a second time, the operation proceeds to S20, and the reset mode is switched to. Then, in S21, the installer 12 executes calibration value setting calibration based on one operation, and sets a calibration value (parameter K') corresponding to the muscle strength of the installer 12 obtained when the calibration operation shown in fig. 16 is executed. Thereafter, the above-described processing from S17 to S19 is executed.

In the present embodiment, the calibration from the second time is performed by the calibration based on the one-time operation, but the present invention is not limited thereto, and the calibration from the second time may be performed by the calibration value setting calibration in the still state, as in the first calibration.

Next, the control processing in each calibration value setting mode will be described with reference to fig. 21 to 23.

Fig. 21 is a flowchart showing a control procedure for performing initial calibration for initial setting. At initial calibration, the installer 12 sets the calibration values by generating muscle strength to enable the dog to remain seated in a resting position relative to the motor load, as described above.

As shown in fig. 21, in S31, a predetermined drive current is supplied to the drive motors 20, 22, 24, 26 in accordance with the sitting stationary state of the installer 12, and a drive force (input power) is supplied as a load. Thus, the installer 12 can generate the driving force against the driving motors 20, 22, 24, 26 in the seated state.

In S32, a myoelectric potential signal of the installer 12 is acquired from each of the myoelectric potential sensors 38a, 38b, 40a, 40b, 42a, 42b, 44a, and 44 b. Then, in S33, virtual power is derived from the measured myoelectric potential signal calculation.

Then, the process proceeds to S34, where the input power supplied as the load is compared with the virtual power. Then, in S35, the ratio between the input power and the virtual power is found. In subsequent S36, the parameters corresponding to the respective operation stages stored in the calibration database 148 are read, and the calibration values (calibration parameters) of the control signals supplied to the motor drive sources 92 to 95 are obtained by multiplying the parameters by the ratios. Next, the process proceeds to S37, where the calibration parameter is set as the autonomous control parameter.

Thus, the installer 12 who has the auxiliary motion installation tool 18 installed can automatically perform the calibration of the body signal according to the current state while keeping the sitting state, and there is no need for the troublesome work of installing a hammer as a load on the installer or replacing the hammer with a coil spring to perform the calibration as in the conventional method. Therefore, the labor and time required for the calibration can be significantly reduced, and the practical use and the popularization of the attachment type motion assisting device 10 can be further promoted.

In addition, for those installers 12 whose muscle strength declines, it is not necessary to impose an excessive burden for calibration on them, and the present invention can set the calibration value in accordance with the state of the installer 12, accurately supply the driving force based on the myoelectric potential signal of the installer 12 to the installer 12, and interlock it with the action of the installer 12.

Therefore, when the calibration is performed, the assist force according to the consciousness of the installer 12 is provided by the drive source, and the assist force is not excessively large or small, so that the operation of the installer 12 can be stably assisted, and the reliability of the attachment type operation assisting device can be further improved.

In particular, calibration can be performed with care when the installer 12 is like a novice, even though it is considered difficult to operate the installation aid 18 as intended. Therefore, even if the installer 12 is a disabled person who cannot move freely, it can avoid the disadvantageous actions on their body and perform calibration to compensate for the weakness on their body without any special operation.

The calibration in the above-described reset mode 1 will be described with reference to fig. 22.

Fig. 22 is a flowchart showing a control procedure of resetting calibration by one operation. Here, when performing the resetting calibration based on one motion, the installer 12 performs only one motion of moving the knees from the flexed state to the extended state while keeping the sitting posture. In addition, the storage unit 130 stores standard myoelectric potentials corresponding to the calibrated operation in advance.

As shown in fig. 22, in S41, it is determined whether or not there is a detection signal detected by the angle sensors 74 and 76 of the knee joint. Then, the angle sensors 74 and 76 detect changes in joint angle of the second joint 66 that occur when the installer 12 performs the knee extension and contraction operation in the sitting state shown in fig. 16. Thereafter, the process proceeds to S42, where the knee operation angle is set based on the detection signals detected by the angle sensors 74 and 76.

Next, the process proceeds to S43, where a standard myoelectric potential corresponding to the action angle of the knee is read from the storage unit 130. In subsequent S44, the measured values of the myoelectric potential of the installer 12 are read from the respective myoelectric potential sensors 38a, 38b, 40a, 40b, 42a, 42b, 44a, 44 b. Then, in S45, the standard myoelectric potential and the measured myoelectric potential are compared.

In S46, a ratio between the standard myoelectric potential and the measured myoelectric potential is determined. Then, in S47, a parameter corresponding to the knee operating angle stored in the calibration database 148 is read, and the parameter is multiplied by the above ratio to obtain a calibration value (calibration parameter) of the control signal to be supplied to the motor drive sources 92 to 95. Next, the process proceeds to S48, where the calibration parameters are set as the autonomous control parameters.

In this way, since the calibration from the second time can calibrate the parameter k' only by the action (one action) of turning the knee part while keeping the sitting state without using the driving force of the driving motors 20, 22, 24, 26, not only the physical burden on the installer 12 can be greatly reduced, but also the preparation time required from the installation of the action assisting unit 18 to the calibration can be shortened, and therefore, the calibration from the second time can make the start of walking faster.

The calibration in the above-described reset mode 2 will be described with reference to fig. 23. In this reset mode 2, the installer 12 performs a standard operation from the sitting state to the standing state (operation stages a1 to a4), and then performs a sitting operation (operation stages a4 to a1) (see fig. 9).

As shown in fig. 23, in S51, it is determined whether or not there is a detection signal detected by the angle sensors 70, 72, 74, and 76 provided in the motion assisting attachment tool 18. Then, the angle sensors 70, 72, 74, and 76 detect changes in joint angles that occur when the installer 12 performs the operation shown in fig. 9 with respect to the first joint 64 and the second joint 66. Thereafter, the process proceeds to S52, where the operation job stored in the calibration database 148 is selected based on the detection signals detected by the angle sensors 70, 72, 74, and 76, and the standard operation of the installer 12 is set.

In subsequent S53, the standard myoelectric potentials corresponding to the standard motions of the first joint 64 and the second joint 66 are read from the storage unit 130. Next, the process proceeds to S54, where the measured values of the myoelectric potential of the installer 12 are read from the myoelectric potential sensors 38a, 38b, 40a, 40b, 42a, 42b, 44a, and 44 b. Then, in S55, the standard myoelectric potential and the measured myoelectric potential are compared.

In S56, the ratio between the standard myoelectric potential and the measured myoelectric potential is determined. Then, in S57, a parameter corresponding to the knee operating angle stored in the calibration database 148 is read, and the parameter is multiplied by the above ratio to obtain a calibration value (calibration parameter) of the control signal to be given to the motor drive sources 92 to 95. Next, the process proceeds to S58, where the calibration parameters are set as the autonomous control parameters.

In subsequent S59, it is determined whether or not the calibration operation job is completed. In S59, if there is an operation stage in the calibration operation job, the process proceeds to S60, and the process is updated to the next operation stage, and the process after S53 is executed again.

In this way, since the parameter k' can be calibrated without using the driving force of the driving motors 20, 22, 24, 26 in the calibration from the second time, not only can the physical burden on the installer 12 be greatly reduced, but also the preparation time from the installation of the motion assisting unit 18 to the calibration can be shortened.

As described above, according to the present invention, the installer 12 can perform the calibration of the surface muscle potential by performing the flexion and extension movements, or the calibration in accordance with the individual condition can be performed by performing the standard movements of the knees which the installer 12 performs while sitting on the chair, and thus, the installer 12 can perform the calibration using the movements which the installer 12 can perform, even if the installer is a handicapped person, or can perform the calibration using other movements (operation work) as the standard movements.

Industrial application

Although the above-described embodiment has been described with reference to the example of the motion assist device 10 that provides the assist force to the legs of the wearer 12, the present invention is not limited to this, and, for example, it is needless to say that the present invention may be applied to a motion assist device that provides the assist force to the wrist.

Although the above embodiment has described only a configuration in which the driving force of the electric motor is used as the assist force, it is needless to say that the present invention can be applied to a device that generates the assist force using a driving source other than the electric motor.

The invention is not limited to the specific embodiments described above, but other variations may be substituted without departing from the scope of the claims, and those variations are still within the scope of the invention.

Claims (11)

1. A mount-type motion assist device, comprising:

a detection unit for detecting a body signal generated by the installer;

an action assisting unit having a driving source for supplying power to the installer;

a control unit for controlling the driving source to generate an auxiliary power corresponding to the body signal detected by the detection unit;

wherein the content of the first and second substances,

the mounting type motion assisting device has a calibration unit that sets a calibration value based on the body signal detected by the detection unit, the body signal corresponding to a driving force provided by the driving source as a load.

2. A mount-type motion assist device, comprising:

a detection unit for detecting a body signal generated by the installer;

an action assisting unit having a driving source for supplying power to the installer;

a control unit for controlling the driving source to generate an auxiliary power corresponding to the body signal detected by the detection unit;

it also has:

a load generating unit for supplying an external load, which is a predetermined driving force supplied from the driving source when the motion assist unit is mounted on the body of the installer;

a calibration value setting unit for generating a parameter for the control unit to perform operation processing based on the body signal generated against the driving force supplied from the load generation unit, which is detected by the detection unit, and setting the parameter as a calibration value specific to the installer.

3. The mounted motion assist device of claim 1,

the calibration unit has a database for storing data of correspondence between the body signal detected by the detection unit and a control signal for controlling the drive source, and the control unit calibrates the control signal stored in the database based on the calibration value set by the calibration value setting unit.

4. The mounted motion assist device of any one of claims 1 to 3,

the detection unit is used in a state of being attached to the skin of the installer, and detects the myoelectric potential of the installer as the body signal.

5. A mounted motion assist device as defined in claim 1 or 2, having:

a waistband;

a right foot assisting part disposed at a lower right portion of the waistband;

a left foot assisting part arranged at the left lower part of the waistband;

wherein the content of the first and second substances,

the right foot assisting portion and the left foot assisting portion have:

a first support extending downwardly from the waist belt to support the waist belt;

a second bracket extending downwardly from said first bracket;

a third bracket extending downwardly from said second bracket;

a fourth bracket disposed at a lower end of the third bracket and supporting a sole portion of the installer;

a first joint between the lower end of the first bracket and the upper end of the second bracket;

a second joint between a lower end of the second bracket and an upper end of the third bracket.

6. The mounted motion assist device of claim 5,

the first joint is provided at a position corresponding to the height of the wearer's crotch joint, and the second joint is provided at a position corresponding to the height of the wearer's knee joint.

7. The mounted motion assist device of claim 5,

the first joint is provided with a first drive source for transmitting a drive force to rotate the second bracket, and the second joint is provided with a second drive source for transmitting a drive force to rotate the third bracket.

8. The mounted motion assist device of claim 7,

the first drive source and the second drive source have angle sensors for detecting joint angles.

9. A calibration device for making a body signal and an auxiliary power correspond to a predetermined relationship each time an action assisting unit having a drive source generating the auxiliary power corresponding to the body signal issued by an installer is installed on the installer, comprising:

a first storing unit for storing in advance a first correspondence relationship between the power and the body signal generated by the installer who installs the motion assisting unit;

a second storing unit for storing in advance a second correspondence relationship between the power and the body signal generated by the installer in the course of performing a predetermined basic action;

wherein the content of the first and second substances,

the motion assisting unit calibrates the assisting power corresponding to the body signal according to the body signal emitted when the installer performs the basic motion and the second corresponding relationship so as to satisfy the first corresponding relationship each time the motion assisting unit is installed on the installer.

10. The calibration device of claim 9,

the first correspondence relationship is a relationship in which the dynamic force has a positive correlation with the body signal, and the second correspondence relationship is a relationship in which a change in the body signal and a change in the dynamic force of the basic motion are present.

11. A calibration method which enables a computer to carry out calibration for making a body signal and an auxiliary power correspond to a desired relationship each time a motion assisting unit having a drive source generating the auxiliary power corresponding to the body signal issued by an installer is installed on the installer, comprising:

a first step of causing the computer to execute an operation of previously storing a first correspondence relationship between the power and the body signal generated by the installer who has installed the motion assisting unit in a first storage unit, and storing a second correspondence relationship between the power and the body signal generated during the installer's execution of a predetermined basic motion in a second storage unit;

a second step of causing the computer to execute an operation of calibrating the assist power corresponding to the body signal so as to satisfy the first correspondence relationship stored in the first storage unit, based on the body signal generated when the installer executes the basic motion and the second correspondence relationship stored in the second storage unit, when the motion assist unit is installed on the installer.