JP2008200512A - Wearable action-assist device, and method and program for controlling wearable action-assist device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a wearable action-assist device, and a method and program for controlling wearable action-assist device which can reduce uncomfortable feeling to a wearer as much as possible. <P>SOLUTION: A wearable action-assist device comprises an action-assist wearable tool 2 having an actuator 201, a voluntary control means 14 for generating power reflecting the intention of the wearer 1 in the actuator 201 by use of a biosignal, an autonomous control means 7 generating an autonomous command signal for estimating a task phase of the wearer 1 and generating power reflecting the estimated phase in the actuator 201 by comparing a reference parameter stored in the database 6 with a physical quantity detected by a physical quantity sensor 13, a signal combining means 8 to combine the command signal from the voluntary control means 4 and the autonomous control means 7, and a driving current generation means 5 which generates current corresponding to a total command signal composed by signal combining means 8 and supplies it to the actuator 201. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a wearable movement assist device that assists or substitutes for a wearer's movement, a control method for the wearable movement assist device, and a control program, and particularly relates to a wearable movement assist that can suppress discomfort given to the wearer. The present invention relates to a control method for a device, a wearable motion assist device, and a control program.

  For the physically handicapped and the elderly, it is often very difficult to perform an operation that can be easily performed by a healthy person. To date, various auxiliary devices have been developed and put to practical use. In such an auxiliary device, a wearer rides like a wheelchair or a nursing bed, and an actuator such as a motor is driven by a switch to assist a shortage of force. And a device that assists the force required for operation. A so-called wearable motion assist device worn by humans can generate the necessary power at any time based on the wearer's intention and does not require a caregiver. It is very convenient for rehabilitation of sick people and is expected to be put to practical use. As such a wearable movement assist device, the myoelectric potential signal accompanying the wearer's muscle activity is detected, and the actuator is arbitrarily controlled according to the wearer's intention by driving the actuator based on the detection result. An apparatus has been proposed (Non-Patent Document 1).

  By the way, in the wearing type movement assist device, there is a problem that the operation becomes awkward if the timing for applying the power for movement assistance to the wearer is not in harmony with the movement of the wearer, and gives the wearer a so-called unnatural feeling. Here, it is known that in order to harmonize the timing of power application with the movement of the wearer, it is necessary to make the timing earlier by a required minute time than the movement of the wearer.

  However, in the wearable movement assist device of Non-Patent Document 1, since the process for generating power to the actuator is started after detecting the myoelectric potential signal from the wearer, the timing of applying power is higher than the movement of the wearer. There was a risk that the wearer might feel uncomfortable with the delay. Therefore, conventionally, human actions are classified into a plurality of patterns (tasks), and each task is divided into a plurality of predetermined minimum operation units (phases), and a current having a preset magnitude is supplied for each phase. Thus, an apparatus for driving and controlling the actuator has been proposed (for example, Non-Patent Documents 2 and 3).

In these wearable movement assist devices, the wearer's task phase is estimated based on physical quantities such as joint angles detected from the wearer, and the actuator is controlled (autonomous control) according to the estimated phase. The uncomfortable feeling caused by the delay in the timing of power application is reduced.
Takao Nakai, Suwoong Lee, Hiroaki Kawamoto and Yoshiyuki Sankai, "Development of Power Assistive Leg for Walking Aid using EMG and Linux," Second Asian Symposium on Industrial Automation and Robotics, BITECH, Bangkok, Thailand, May 17-18, 2001 "Predictive Control Estimating Operator's Intention for Stepping-up Motion by Exo-Skeleton Type Power Assist System HAL," Proceedings of the2001 IEEE / RSJ, International Conference on Intelligent Robots and Systems, Maui, Hawaii, Oct. 29-Nov. 03, 2001, pp. 1578-1583 Hideo Lee, Yoshiyuki Sankai, “Power Assist Control of Standing and Walking Using Phase Sequence and EMG”, Proceedings of the 19th Annual Conference of the Robotics Society of Japan (2001)

  However, in the control system of the wearable motion assisting device of Non-Patent Documents 2 and 3, since it is based on autonomous control, when an unexpected motion change such as a stumbling occurs, the phase of the corresponding task is changed. Switching could not be performed smoothly, and there was a risk of giving the wearer a noticeable discomfort.

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a wearable motion assist device, a control method for the wearable motion assist device, and a control program that can suppress discomfort given to the wearer as much as possible.

In the first embodiment of the present invention, the wearable motion assisting device that assists or substitutes for the motion of the wearer,
An operation assisting wearing device having an actuator for applying power to the wearer;
A biological signal sensor for detecting a biological signal of the wearer;
A biological signal processing means for acquiring a nerve transmission signal for operating the wearer's musculoskeletal system and a myoelectric potential signal associated with muscle activity from the biological signal detected by the biological signal sensor;
Optional control means for generating a command signal for causing the actuator to generate power according to the intention of the wearer, using a nerve transmission signal and a myoelectric potential signal acquired by the biological signal processing means;
Drive current generation means for generating a current corresponding to the nerve transmission signal and a drive current corresponding to the myoelectric potential signal based on the command signal generated by the optional control means, and supplying the current to the actuator. It is characterized by that.

The control method of the wearable motion assist device is as follows:
In a state where an operation assisting wearing device having an actuator for applying power to the wearer is worn by the wearer,
Detecting a biological signal of the wearer,
From the detected biological signal, obtain a nerve transmission signal for operating the wearer's musculoskeletal system and a myoelectric potential signal accompanying muscle activity,
Using the acquired nerve transmission signal and myoelectric potential signal, generating an optional command signal for causing the actuator to generate power according to the intention of the wearer,
Based on the generated arbitrary command signal, a current corresponding to the nerve transmission signal and a current corresponding to the myoelectric potential signal are respectively supplied to the actuator.

Further, the control program for the wearable motion assisting device is stored in a computer for controlling the actuator.
Processing for detecting the wearer's biological signal;
A process for acquiring a nerve transmission signal for operating the wearer's musculoskeletal system and a myoelectric potential signal associated with muscle activity from the biological signal;
Using the acquired nerve transmission signal and myoelectric potential signal, a process for generating an optional command signal for causing the actuator to generate power according to the intention of the wearer;
Based on the generated optional command signal, a current corresponding to the nerve transmission signal and a current corresponding to the myoelectric potential signal are respectively generated and processed to be supplied to the actuator.

  The wearable movement assist device of the first embodiment preferably includes a physical quantity sensor that detects a physical quantity related to the wearer's movement. The biological signal processing means includes means for amplifying a biological signal composed of the nerve transmission signal and a myoelectric potential signal, a first filter for extracting the nerve transmission signal from the biological signal, and the muscle from the biological signal. It is preferable to have a second filter for extracting a potential signal.

  In the wearable motion assist device according to the first embodiment, the drive current generation means includes a total of a pulse current generated according to the nerve transmission signal and a current generated so as to be substantially proportional to the myoelectric potential signal. It is preferable that an electric current is supplied to the actuator and the operation of the actuator is started by the pulse current.

  In the wearable motion assisting device of the first embodiment, when the drive current generating means starts supplying current to the actuator, the drive current generating means is larger than the lower limit value of the current that can drive the actuator. It is preferable to generate the pulse current or the total current.

  In the wearable movement assist device of the first embodiment, each reference parameter of a series of minimum movement units (phases) constituting a movement pattern of a wearer classified as a task, and a power application rate (power assist rate) by the actuator ), And the optional control means compares the physical quantity detected by the physical quantity sensor with a reference parameter stored in the database, so that the wearer Estimate the phase of the task that is going to be performed, specify the power assist rate according to this phase based on the correspondence, and generate a command signal for causing the actuator to generate the power that becomes the power assist rate It is preferable.

  In the wearable movement assist device according to the first embodiment, when the wearer operates with reflexes, the drive current generation unit generates a current for driving the actuator in a direction opposite to the operation for a predetermined time. It is preferable to supply a current for driving the actuator in the direction of the operation after supplying only the current.

  In the control method for the wearable movement assist device of the first embodiment, the actuator calculates a total current of a pulse current generated according to the nerve transmission signal and a current generated so as to be substantially proportional to the myoelectric potential signal. Preferably, the operation of the actuator is started by supplying the pulse current.

  In the control method for the wearing-type motion assisting device according to the first embodiment, when the supply of current to the actuator is started, the pulse current or the pulse current or the current is set to be larger than the lower limit value of the current that can drive the actuator. It is preferable to supply the total current.

  In the control method for the wearable movement assist device of the first embodiment, the physical quantity related to the wearer's movement is further detected, and the detected physical quantity signal and a series of minimums constituting each movement pattern of the wearer classified as a task By comparing each reference parameter of the operation unit (phase), the phase of the task that the wearer is going to perform is estimated, and a required power application rate (power assist rate) corresponding to this phase is obtained. It is preferable that an optional command signal for generating power in the actuator is generated, a drive current corresponding to the optional command signal is generated, and supplied to the actuator.

  In the control method for the wearable movement assist device according to the first embodiment, when the wearer operates by reflexes, after supplying a current for driving the actuator in a direction opposite to the operation for a predetermined time, It is preferable to supply a current for driving the actuator in the direction of the operation.

  In the control program for the wearable movement assist device of the first embodiment, the computer generates a pulse current generated according to the nerve transmission signal and a current generated so as to be substantially proportional to the myoelectric potential signal. It is preferable to supply a total current to the actuator and to perform a process for starting the operation of the actuator by supplying the pulse current.

  In the control program for the wearing-type motion assisting device according to the first embodiment, when the supply of current to the actuator is started, the computer is set to be larger than the lower limit value of the current that can drive the actuator. It is preferable to perform processing for setting the pulse current or the total current.

  In the control program for the wearable movement assist device according to the first embodiment, the computer includes, in the computer, a reference parameter for each of a series of minimum movement units (phases) constituting a wearer movement pattern classified as a task, and the actuator. The process for accessing the database storing the power application rate (power assist rate) by the required correspondence relationship, the process for detecting the physical quantity related to the wearer's movement, and the detected physical quantity, By comparing with the reference parameters stored in the database, the phase of the task that the wearer is going to perform is estimated, the power assist rate corresponding to this phase is defined based on the correspondence, and the power assist It is preferable to perform processing for generating the power to be There.

  In the control program for the wearable movement assist device according to the first embodiment, when the wearer operates by reflexes, the computer is provided with a drive current for driving the actuator in the opposite direction of the operation. It is preferable that processing for supplying a drive current for driving the actuator in the direction of the operation is performed after the supply for the period of time.

In the second embodiment of the present invention, the wearable movement assist device that assists or substitutes for the movement of the wearer,
An operation assisting wearing device having an actuator for applying power to the wearer;
A biological signal sensor for detecting a biological signal of the wearer;
A physical quantity sensor for detecting a physical quantity related to the movement of the wearer;
Optional control means for generating a command signal for causing the actuator to generate power according to the intention of the wearer, using a biological signal detected by the biological signal sensor;
A database that stores reference parameters for each of a series of minimum motion units (phases) constituting the motion pattern of the wearer classified as a task;
A command for estimating a phase of the wearer's task by comparing a physical quantity detected by the physical quantity sensor with a reference parameter stored in the database, and causing the actuator to generate power corresponding to the phase. An autonomous control means for generating a signal;
A signal synthesis means for synthesizing a command signal from the optional control means and a command signal from the autonomous control means;
Drive current generating means for generating a total current corresponding to the total command signal synthesized by the signal synthesizing means and supplying the total current to the actuator.

The control method of the wearable motion assist device is as follows:
In a state where an operation assisting wearing device having an actuator for applying power to the wearer is worn by the wearer,
Detecting physical quantities of the wearer's biological signal and the wearer's motion,
Using the detected biological signal, generate an optional command signal for causing the actuator to generate power according to the wearer's intention,
Estimate the phase of the task that the wearer is trying to perform by comparing the detected physical quantity with the reference parameters of each of the series of minimum motion units (phases) that make up the wearer's movement pattern classified as a task. And generating an autonomous command signal for causing the actuator to generate power according to this phase,
Synthesize these optional command signals and autonomous signals,
A current corresponding to the synthesized total command signal is generated and supplied to the actuator.

In the control program for the wearable motion assist device, the computer for controlling the actuator includes:
A process for detecting a physical quantity relating to the wearer's biological signal and the operation of the wearer, respectively;
A process for generating an optional command signal for causing the actuator to generate power according to the intention of the wearer using the detected biological signal;
By comparing the detected physical quantity with reference parameters of each of a series of minimum operation units (phases) constituting the operation pattern of the wearer classified as a task, the phase that the wearer is going to perform is estimated, Processing for generating an optional command signal for causing the actuator to generate power according to this phase;
A current corresponding to a total command signal obtained by synthesizing the generated arbitrary command signal and autonomous command signal is generated, and processing for supplying the current to the actuator is performed.

  In the wearable motion assisting device of the second embodiment, the database is configured such that a ratio (hybrid ratio) between a command signal from the optional control means and a command signal from the autonomous control means is a reference parameter of the phase. And the signal synthesis means, according to the phase of the task estimated by the autonomous control means, the hybrid ratio specified based on the correspondence relation, Preferably, the command signal from the optional control means and the command signal from the autonomous control means are combined.

  In the wearable movement assist device according to the second embodiment, a nerve transmission signal for operating the wearer's musculoskeletal system and a myoelectric potential signal associated with muscle activity are acquired from the biological signal detected by the biological signal sensor. It is preferable that the driving current generation unit starts the operation of the actuator by supplying a pulse current generated according to the nerve transmission signal acquired by the biological signal processing unit.

  In the wearable motion assist device of the second embodiment, when the drive current generating means starts to supply current to the actuator, the drive current generating means is larger than the lower limit value of the current that can drive the actuator. It is preferable to generate the pulse current or the total current.

  In the wearable motion assist device of the second embodiment, the database stores the reference parameters of the phases and the required power application rate (power assist rate) by the actuator so as to have a required correspondence relationship. The signal synthesizing unit defines a power assist rate according to the phase of the task estimated by the autonomous control unit based on the correspondence relation, and the optional control unit sets the power assist rate to satisfy the power assist rate. It is preferable to synthesize the command signal and the command signal from the autonomous control means.

  In the wearable movement assist device according to the second embodiment, when the wearer is operated by reflexes, the drive current generating means generates a current for driving the actuator in a direction opposite to the movement for a predetermined time. It is preferable to supply a current for driving the actuator in the direction of the operation after supplying only the current.

  In the control method for the wearable motion assisting device of the second embodiment, the ratio (hybrid ratio) between the voluntary command signal and the autonomous command signal is a required correspondence with each reference parameter of the phase. Preferably, the hybrid ratio corresponding to the estimated task phase is defined based on the correspondence relationship, and the total command signal is synthesized so as to be the hybrid ratio.

  In the control method of the wearable motion assist device of the second embodiment, the neurotransmission signal is set to be larger than the lower limit value of the current that can drive the actuator when the supply of the current to the actuator is started. It is preferable to supply a current corresponding to the current or a total current of the current and the current corresponding to the myoelectric potential signal.

  In the control method for the wearable movement assist device of the second embodiment, the ratio of power to be given to the wearer (power assist rate) is associated in advance with each reference parameter of the phase, and the estimated task The total command signal is preferably set so that the power assist rate according to the phase is obtained.

  In the control method of the wearable movement assist device according to the second embodiment, when the wearer moves by reflexes, a drive current for driving the actuator in the opposite direction of the movement is generated for a predetermined time. It is preferable to drive the actuator in the direction of the operation later.

In the control program for the wearable movement assist device of the second embodiment, the computer for controlling the actuator includes:
A process for accessing a database in which a ratio (hybrid ratio) between the voluntary command signal and the autonomous command signal is stored so as to have a required correspondence with each reference parameter of the phase, and the detected By comparing the physical quantity with the reference parameter stored in the database, the phase of the task that the wearer is going to perform is estimated, and the hybrid ratio corresponding to this phase is defined based on the correspondence relationship, It is preferable to perform processing for synthesizing the total command signal so as to obtain a hybrid ratio.

  In the control program for the wearable motion assist device of the second embodiment, when starting supplying the current to the actuator to the computer, the program is set to be larger than the lower limit value of the current that can drive the actuator. It is preferable to perform processing for setting the pulse current or the total current.

  In the control program for the wearable movement assist device according to the second embodiment, each of the reference parameters of a series of minimum operation units (phases) constituting the wearer's movement pattern classified as a task is stored in the computer. The total command signal is set so as to obtain a power assist rate corresponding to the estimated task phase and a process for accessing a database stored in association with the ratio of power to be applied to the power (power assist rate) It is preferable to perform the process for this.

  In the control program for the wearable movement assist device according to the second embodiment, when the wearer operates by reflexes, the computer is provided with a drive current for driving the actuator in a direction opposite to the operation. It is preferable that processing for driving the actuator in the direction of the operation is performed after the generation of the time.

  According to the present invention, an optional command signal for causing the actuator to generate power according to the wearer's intention, and the phase of the task estimated by comparing the detected physical quantity with the reference parameter stored in the database. Since the autonomous command signal for causing the actuator to generate the corresponding power is synthesized, the actuator can be started quickly, and the optional operation can be performed smoothly without a sense of incongruity.

  In addition, according to the present invention, by controlling the hybrid ratio between the voluntary command signal and the autonomous command signal, optimal operation assistance for the muscle strength of the wearer can be performed without delay in starting power assistance. Can do. If the hybrid ratio stored in the database is extracted for each phase, the hybrid ratio can be automatically changed. Thereby, it is possible to move more smoothly with a hybrid ratio suitable for each operation.

  According to the present invention, the total current of the pulse current generated according to the nerve transmission signal and the current generated so as to be substantially proportional to the myoelectric potential signal is supplied to the actuator, and the operation of the actuator is performed by supplying the pulse current. By starting the operation, it is possible to prevent a delay in the start of driving of the actuator. Further, when the pulse current or the total current is less than the current at which actuator driving can be started, the nerve current is transmitted by amplifying the pulse current so that the pulse current or the total current becomes equal to or higher than the current at which actuator driving can be started. The actuator can be started in response to the signal accurately.

  According to the present invention, when performing an operation using reflexes, the actuator is driven for a predetermined time in the opposite direction immediately before driving in the operation direction, so that the operation is smoothly performed using the wearer's reflexes. can do.

  Further, according to the present invention, by generating the power that becomes the power assist rate according to the phase of the task estimated by comparing the physical quantity and the reference parameter, it is possible for the wearer with different physical strength. Optimal power can be applied to assist power.

  Using the wearable movement assist device of the present invention having the above features, even those who do not have sufficient muscle strength to perform physical movements or who have difficulty in physical movements, such as persons with physical disabilities and elderly persons Smooth operation can be performed without a sense of incongruity. Also, even those who have heavy equipment to perform dangerous work such as disposal of explosives will be light as if there is no heavy equipment if they are equipped with the wearable movement assist device of the present invention. Can work.

Hereinafter, although this invention is demonstrated for every embodiment, the characteristic of each embodiment is applicable also to other embodiment unless there is particular notice.
[1] First Embodiment (A) Configuration of Wearable Movement Auxiliary Device A wearable movement assist device according to a first embodiment includes a movement assist wearing device having an actuator and a living body that detects a biological signal of the wearer. A signal sensor, a biological signal processing means for acquiring a nerve transmission signal and a myoelectric potential signal from the biological signal, and a command signal for causing the actuator to generate power according to the wearer's intention using the nerve transmission signal and the myoelectric potential signal And a drive current generation unit that generates currents corresponding to the nerve transmission signal and the myoelectric potential signal based on a command signal from the optional control unit and supplies the current to the actuator. When the actuator generates power having a power assist rate corresponding to the phase of the task that the wearer is going to perform, the wearable movement assisting device is provided with a physical quantity sensor that detects a physical quantity related to the wearer's movement.
(1) Drive System FIG. 1 schematically shows an example drive system (hardware system). This wearable movement assist device has a movement assist wearing tool 2 (not shown in the figure of one leg) that is worn on the lower body of a human (hereinafter also referred to as a wearer) 1 and a biological signal from the lower half (eg, thigh). A biological signal sensor 221 to be detected, a gravity center sensor 222 that is attached to the sole of the foot and detects the center of gravity of the wearer 1, and a biological signal that acquires a nerve transmission signal and a myoelectric potential signal from the biological signal detected by the biological signal sensor 221 A processing unit 3; a control device 20 that controls driving of the actuator 201 of the auxiliary motion wearing tool 2 based on a nerve transmission signal and a myoelectric potential signal; and a power source (battery) for supplying power to the control device 20, the actuator 201, and the like , External power source) 21.

  As shown in FIG. 2, the motion assisting wearing device 2 includes a waist joint 203a that rotatably joins the upper arm 202a and the intermediate arm 202b, and a knee joint 203b that rotatably joins the intermediate arm 202b and the lower arm 202c. And a heel joint 203c that rotatably joins the lower arm 202c and the heel part 205, an actuator 201a provided on the waist joint 203a, and an actuator 201b provided on the knee joint 203b. Fixing tools 205a and 205b such as Velcro (registered trademark) fixed to the thigh and calf of the wearer 1 are attached to the intermediate arm 202b and the lower arm 202c. Each actuator 201a, 201b comprises a motor and a reduction gear.

The upper arm 202a is fixed to a waist portion 204 that is wound around the body of the wearer 1 and fixed. A protrusion 204a that opens up and down is provided at the upper edge of the back side of the waist 204, and a lower protrusion 220a of a bag 220 that houses the control device 20, the power source 21, and the like is provided in the opening of the protrusion 204a. Engage. In this way, the load of the bag 220 is received by the waist portion 204. The heel portion 205 has an integral shape that completely covers the heel of the wearer 1, and one side wall thereof extends higher than the other side wall, and a heel joint 203 c is attached to the upper end portion thereof. For this reason, the loads of the motion assisting wearing device 2 and the bag 220 are all supported by the collar portion 205 and do not apply to the wearer 1.
(2) Control System FIG. 3 shows a control system of the wearable movement assist device of the first embodiment. The wearer 1 and the motion assisting wearing tool 2 constitute a human machine system 10. The control device 20 also has optional control means 4. A biological signal sensor 221 for detecting a biological signal of the wearer 1 is connected to the input terminal of the optional control means 4, and a drive current generating means 5 is connected to the output terminal of the optional control means 4. is there. The drive current generating means 5 is connected to actuators 201a and 201b (hereinafter collectively referred to as actuator 201) of the motion assisting wearing device 2.
(A) Sensor The wearable movement assist device of the first embodiment requires a biosignal sensor 221 that detects a biosignal from the wearer 1 in a state of being worn on the human 1. The biological signal sensor 221 is usually attached to the skin of the wearer 1, but may be embedded in the body. In addition, it is preferable to have a center of gravity sensor 222 as shown in FIG. For example, a plurality of center-of-gravity sensors 222 are affixed to the soles of the feet, and the motion direction of the human body can be predicted by detecting which center-of-gravity sensor 222 has the most weight. Further, in order to improve the control accuracy, for example, (1) sensors (force sensor, torque sensor, current sensor, angle sensor, angular velocity sensor, acceleration sensor, floor for obtaining a signal indicating the operation state of the wearer 1) Reaction force sensor, etc.), (2) sensors (CCD, laser sensor, infrared sensor, ultrasonic sensor, etc.) for obtaining external information (for example, presence or absence of obstacles), (3) nerve transmission signal and myoelectric potential signal Sensors (body temperature sensor, pulse sensor, electroencephalogram sensor, electrocardiographic sensor, sweat sensor, etc.) for obtaining other biological signals can be provided. Since these sensors are known per se, their respective explanations are omitted.
(B) Biological signal processing means The biological signal detected by the biological signal sensor 221 has a nerve transmission signal and a myoelectric potential signal. The nerve transmission signal can be said to be a communication signal, and (i) precedes the myoelectric potential signal [see FIG. 4 (a)], or (ii) overlaps the leading portion of the myoelectric potential signal [FIG. 4 (b). )reference]. Since the frequency of the nerve transmission signal is generally higher than that of the myoelectric signal, it can be separated by using different bandpass filters. The nerve transmission signal can be extracted by a high-band (for example, 33 Hz to several kHz) bandpass filter 32 after the biological signal is amplified by the amplifier 31, and the myoelectric potential signal can be extracted after the biological signal is amplified by the amplifier 31. The band-pass filter 33 having a medium band (for example, 33 Hz to 500 Hz) can be used. 4A and 4B, the filters are connected in parallel. However, the present invention is not limited to this, and both filters may be connected in series. Further, the nerve transmission signal may overlap not only at the head portion of the myoelectric potential signal but also at the head portion and thereafter. In this case, only the head portion of the nerve transmission signal may be used for generating a pulse current described later.

  Smoothing processing is performed on the nerve transmission signal and the myoelectric potential signal. Each current in FIG. 4 (a) and FIG. 4 (b) is generated by the drive current generation means 5 with a command signal obtained by smoothing the signal from the biological signal processing means 3 as an input. As shown in FIG. 4A, since the nerve transmission signal has a narrow width, the smoothing alone becomes a pulse shape, and the current generated by the drive current generator 5 based on this nerve transmission signal also becomes a pulse shape. The current (pulse current) obtained based on the nerve transmission signal may be a rectangular wave. On the other hand, as shown in FIG. 4B, the myoelectric potential signal has a wide width, so that it becomes a mountain shape that is substantially proportional to the myoelectric potential by smoothing, and is generated by the drive current generating means 5 based on this myoelectric potential signal. The current that is applied also has a mountain shape.

When the total current of the pulse current generated based on the nerve transmission signal and the current generated proportionally based on the myoelectric potential signal is supplied to the actuator 201, the torque having a magnitude proportional to the total current is supplied. Is generated by the actuator 201. Here, in both cases of FIG. 4A and FIG. 4B, the total current is set to rise at a sufficiently large current, so that the actuator 201 is driven without delay to the wearer 1's intention to operate. Thus, the wearer 1 can perform an operation according to his / her intention without a sense of incongruity. In FIG. 4A and FIG. 4B, the pulse current is shown particularly large, but this is for emphasizing its role. The drive current obtained from the actual pulse current and the myoelectric potential signal It does not indicate the relationship. The magnitude of each current can be appropriately set according to the sense of the wearer 1 during operation.
(C) Optional Control Unit The optional control unit 4 has a function of generating a command signal for causing the actuator 201 to generate power according to the intention of the wearer 1 using a nerve transmission signal and a myoelectric potential signal. Proportional control can be applied as a control law in the optional control means 4. By the proportional control, the command signal value and the drive current value have a proportional relationship, and further, the drive current value and the generated torque value of the actuator 201 have a proportional relationship due to the characteristics of the actuator 201. Therefore, the power assist rate can be controlled to a desired value by generating a required command signal by the optional control means 4. As a control law in the optional control means 4, a combination of proportional control and differential control and / or integral control may be applied.

Here, the power assist rate is a distribution rate between the force generated by the wearer 1 and the force generated by the wearing tool 2, and is adjusted manually or automatically. This power assist rate may be a positive value or a negative value. In the case of a positive assist rate, the generated force of the wearer 2 is added to the generated force of the wearer 1, but in the case of a negative assist rate, the generated force of the wearer 2 is subtracted from the generated force of the wearer 1 ( That is, a load is applied to the wearer 1), and the wearer 1 must generate a force greater than normal.
(D) Drive current generating means When the command signal from the optional control means 4 is input, the drive current generating means 5 responds to the current corresponding to the nerve transmission signal and the myoelectric potential signal based on the command signal. Each of the drive currents is generated and supplied to the actuator 201 to drive the actuator 201.
(B) Control Method and Control Program In a preferred example of the control method of the first embodiment shown in FIG. 5, the motion assisting wearing device 2 having the actuator 201 that applies power to the wearer 1 is provided to the human 1. It wears (ST501), and the biometric signal of the wearer 1 is detected (ST502). As shown in FIG. 4, a nerve transmission signal and a myoelectric potential signal are acquired from the biological signal by the biological signal processing means 3 (ST503), and according to the intention of the wearer 1 using the acquired nerve transmission signal and myoelectric potential signal. An optional command signal for generating power in the actuator 201 is generated (ST504). This optional command signal includes a command signal for generating a pulse current corresponding to the nerve transmission signal and a command signal for generating a drive current proportional to the myoelectric potential signal. By inputting each command signal to the drive current generation means 5, a current to be supplied to the actuator 201 is generated by the drive current generation means 5. Other signals (for example, a signal obtained from a sensor other than the biological signal sensor 221 described in the first embodiment) can be used to generate the optional command signal. In the following embodiments, the same signals as described above can be used as other signals unless otherwise specified.

  Since the current that can drive the actuator 201 has a lower limit (threshold value), the pulse current corresponding to the nerve transmission signal (when the pulse current and the drive current are not superimposed), or the pulse current and the drive current (pulse current and If the total current is less than the lower limit value, the pulse current is not useful for quickly starting the actuator 201, and the actuator 201 starts to drive until the drive current reaches the lower limit value. do not do. In this case, a considerable delay occurs between the time when the cerebrum of the wearer 1 issues an operation start signal (neural transmission signal) and the start of the motion assisting device, and the discomfort given to the wearer 1 becomes large. In order to eliminate this, it is preferable to start driving the actuator 201 immediately according to the pulse current corresponding to the nerve transmission signal.

  In addition, since each arm 202 and each joint 203 of the actuator 201 and the motion assisting wearing tool 2 has a moment of inertia, in order to assist the motion without delay in the intention of the wearer 1, a quick rising torque is generated in the actuator 201. It is preferable to make it. In order to realize these, in this embodiment, when the pulse current 82 and the drive current 81 do not overlap as shown in FIG. 6A, and when the pulse current 83 and the drive current as shown in FIG. In any of the cases where the current 81 is superimposed, if the pulse current 82 (or pulse current 83 + drive current 81) is not equal to or greater than the lower limit value It of the drive startable current of the actuator 201 (No in ST505), the pulse current 82 ( Alternatively, the pulse currents 82 and 83 are amplified so that the pulse current 83 + the drive current 81) becomes equal to or greater than the lower limit value It of the drive startable current (ST505a). In addition, the width of the pulse currents 82 and 83 is increased as necessary (longer than the time corresponding to the nerve transmission signal) so that the actuator 201 can be reliably started. As a result, it is possible to reliably start the actuator 201 by supplying the pulse currents 82 and 83 according to the nerve transmission signal (ST506).

  After driving the actuator 201 in this way, when the driving torque is generated in the actuator 201 so as to be proportional to the driving current 81 corresponding to the myoelectric potential signal (ST507), the operation according to the intention of the wearer 1 is power-assisted. be able to.

  In order to execute the control, a process for detecting a biological signal (ST502), a process for acquiring a nerve transmission signal and a myoelectric potential signal from the biological signal (ST503), and the acquired nerve transmission signal and myoelectric potential signal are used. Processing for generating an optional command signal for generating power according to the intention of the wearer 1 in the actuator 201 (ST504), and based on the generated optional command signal, a pulse current and a muscle corresponding to the nerve transmission signal A control program for generating a driving current corresponding to the potential signal and supplying the driving current to the actuator 201 (ST506, ST507) is transmitted to the control device 20 (for example, a CPU, a hard disk, and the like) A storage device such as a RAM, and a computer such as a personal computer having an input / output device). To. Although the control device 20 can be stored in the bag 220, it is arranged outside the wearable movement assist device as necessary so that signals can be transmitted to and received from the wearable motion assist device wirelessly. May be.

  FIG. 7 shows the task phase estimated from the physical quantity related to the movement of the wearer 1 when performing optional control of the actuator 201 in the wearable movement assist device of the first embodiment, and the power corresponding to the estimated phase. An example will be shown in which an actuator generates power to become an assist rate. In the wearable motion assisting device of FIG. 7, the same reference numerals are given to the same parts as the wearable motion assisting device of FIG. 3, and similar reference numerals are given to similar parts.

  Before describing the details of the wearable motion assisting device in FIG. 7, the task (Task) and its phase (Phase) will be described first. A task is a classification of each operation pattern of the wearer, and a phase is a series of minimum operation units constituting each task. FIG. 8 exemplifies walking (task A), rising (task B), sitting (task C), and ascending or descending stairs (task D) as basic actions of the human 1. It is not necessarily limited to. Each task consists of the above phases. For example, walking task A includes phase 1 in which both feet are aligned, phase 2 in which the right foot is in front, phase 3 in which the left foot is in front and both feet are aligned, and It consists of Phase 4 with the left foot in front. Such a series of phases is referred to as a phase sequence. The power appropriate for assisting the wearer 1 is different for each phase. Therefore, by giving different power assist rates PAR1, PAR2, PAR3, and PAR4 to the phases 1 to 4, optimal operation assistance can be performed for each phase.

  Analyzing each person's movement shows that the rotation angle and angular velocity, walking speed and acceleration, posture, and movement of the center of gravity of each joint in each phase are determined. For example, the typical walking pattern of each person is determined, and it feels most natural when walking in that pattern. Accordingly, the rotation angles and angular velocities of each joint of each person may be obtained empirically for all phases of all tasks and stored in the database as reference parameters (reference rotation angles and angular velocities, etc.).

  The wearable movement assisting device of FIG. 8 includes a human machine system 10 including a wearer 1 and a movement assisting wearing tool 2, and a biological signal processing unit 3 that acquires a nerve transmission signal and a myoelectric potential signal from a biological signal of the wearer 1. And the physical quantity detected by the physical quantity sensor 13 together with the database 6 in which the power assist rate and the like assigned to each phase are stored together with the reference parameters of each phase, and biological signals (including nerve transmission signals and myoelectric potential signals). (Rotational angles and angular velocities of each joint, walking speed and acceleration, posture, movement of the center of gravity, etc., and signals from other sensors as necessary) are acquired, and the acquired physical quantities are compared with the reference parameters in the database 6 The optional control means 14 for generating the optional command signal (including the power assist rate etc.) obtained by this, and the command signal of the optional control means 14 Flip and a driving current generating unit 5 which generates a drive current of the actuator 201 of the motion assisting wearing device 2.

  FIG. 9 shows the task that the wearer 1 is going to perform by comparing the physical quantity with the reference parameter, and the process of estimating the phases therein. The tasks and phases shown in FIG. 9 are those shown in FIG. The illustrated task A (walking), task B (rising), task C (sitting),... Are a series of phases (phase A1, phase A2, phase A3..., Phase B1, phase B2, phase B3,.・ ・ Etc).

  When the wearer 1 starts the operation, the actual measurement values of various physical quantities obtained by the physical quantity sensor 13 are compared with the reference parameters stored in the database 6. This comparison is shown schematically in the graph in FIG. This graph shows knee rotation angle θ and angular velocity θ ′, waist rotation angle θ and angular velocity θ ′, and center of gravity position COG and center of gravity position movement speed COG ′. Of course, the physical quantities to be compared are limited to these. Not.

  The measured physical quantity is compared with the reference parameter at a fixed short time interval. The comparison is performed for a series of phases in all tasks (A, B, C...). That is, all phases (A1, A2, A3..., B1, B2, B3..., C1, C2, C3...) Shown in the upper table of FIG. Will be compared.

  As shown in the graph of FIG. 9, for example, when comparison is made at each time t1, t2, t3,..., A phase having a reference parameter that matches all measured physical quantities can be identified. In order to eliminate coincidence errors, phase identification may be performed after confirming coincidence in a plurality of times. For example, in the example shown in the figure, if the measured value matches the reference parameter of phase A1 at a plurality of times, it can be seen that the current operation is the operation of phase A1. Of course, the phase having the reference parameter that matches the actually measured value is not necessarily the first phase (A1, B1, C1, etc.) of the task.

  FIG. 10 shows a control method for controlling the power assist rate as another example of the first embodiment. Since ST601, ST602, and ST604 to 606 in FIG. 10 are substantially the same as ST501 to 505a in FIG. 5, the description thereof is omitted, and here, the steps of ST607 to 612 are mainly described.

  The physical quantity of the human machine system 10 is detected by the physical quantity sensor 13 (ST603). The physical quantity sensor 13 for physical quantities such as the rotation angle and angular velocity, walking speed and acceleration, and posture of each joint is attached to the motion assisting wearing device 2, but the physical quantity sensor 13 for physical quantities such as movement of the center of gravity is directly attached to the wearer 1. Is preferred.

  The physical quantity is sequentially compared with the reference parameter of each phase of each task stored in the database 6 (ST607). As described with reference to FIG. 9, since all tasks and their phases exist in a matrix, the measured values of physical quantities and the reference parameters of each phase are represented by, for example, A1, A2, A3. , B2, B3..., C1, C2, C3. Since the reference parameters are set so that they do not overlap between all task phases (simply called “task / phase”), when comparing with the reference parameters of all task phases, The phase of the task having the matching reference parameter is known (ST608). Taking into account the measurement error of the actual measurement value of the physical quantity, the number of matches required for the determination is set in advance, and when that number is reached (ST609), the phase of the task corresponding to the actual measurement value of the physical quantity is estimated. (ST610). By referring to the database 6, the power assist rate assigned to the phase corresponding to the operation to be assisted is defined, and the optional command signal is adjusted so that the actuator 201 generates the power that becomes the power assist rate ( ST611). The drive current generation means 5 generates a current (total current) according to the adjusted optional command signal, and drives the actuator 201 by supplying this total current (ST612).

  In order to execute the above control, a process of detecting a biological signal of the wearer 1 (ST602), a process of detecting a physical quantity of the human machine system 10 (ST603), a detected physical quantity, and a phase reference parameter for each task. By comparing (ST607 to 609), a phase that the wearer is going to perform is estimated (ST610), and an optional command signal is generated so that the actuator generates power that has a power assist rate according to the estimated phase. A control program for performing a process (ST611) to be generated and a process (ST612) for generating a current corresponding to an optional command signal and supplying the current to the actuator is stored in the storage device of the control device 20A of the wearable motion assist device To store.

As described above, it is possible to perform smooth operation assistance by generating an optional command signal so that the power assist rate is optimized for each phase, and applying power according to this optional command signal. In addition, by starting the driving of the actuator with a pulse current corresponding to the nerve transmission signal, it is possible to assist the operation without causing a delay in starting the driving (no sense of incongruity).
[2] Second Embodiment (A) Configuration of Wearable Motion Auxiliary Device As illustrated in FIG. 11, the wearable motion assist device of the second embodiment includes a motion assisting wearing tool 2 having an actuator 201. The biological signal sensor 221 that detects the biological signal of the wearer 1, the physical quantity sensor 13 that detects the physical quantity of the human machine system 10, and the biological signal detected by the physical quantity sensor 13 are used in accordance with the intention of the wearer 1. Optional control means 14 for generating a command signal (optional command signal) for causing the actuator 201 to generate power, and a series of minimum operation units (phases) constituting each operation pattern of the wearer 1 classified as a task The database 6 storing the respective reference parameters, the physical quantity detected by the physical quantity sensor 13 and the reference parameters stored in the database 6 are compared. The autonomous control means 7 that estimates the phase of the task of the wearer 1 and generates a command signal (autonomous command signal) for causing the actuator 201 to generate power according to the estimated phase, and optional control means 4, a signal combining unit 8 that combines the command signal from the autonomous control unit 7, and a drive current that generates current corresponding to the total command signal combined by the signal combining unit 8 and supplies the current to the actuator 201. And generating means 5.

  The optional control means 14 itself may be the same as the optional control means 4 of the first embodiment shown in FIG. Specifically, as shown in FIGS. 4A and 4B, an optional command signal corresponding to the nerve transmission signal and the myoelectric potential signal is generated, and a pulse current corresponding to the nerve transmission signal is generated by the actuator 201. It is preferably used as a trigger signal for starting driving.

  As shown in FIG. 8 and FIG. 9, the autonomous control means 7 compares the physical quantity detected by the physical quantity sensor 13 with the reference parameter of each phase of each task stored in the database 6, so that the wearer 1 And a function of generating an autonomous command signal for causing the actuator 201 to generate power according to this phase. Therefore, the description regarding FIG. 8 and FIG. 9 applies to the autonomous control means 7 as it is.

  The signal synthesizing means 8 synthesizes the optional command signal from the optional control means 14 and the autonomous command signal from the autonomous control means 7. In autonomous control, for example, constant power is applied for each phase. Therefore, the synthesized command signal has a waveform that causes the actuator 201 to generate power by voluntary control that changes from the start to the end of the operation and power obtained by adding power by a certain autonomous control for each phase. The effect of the command signal synthesis is apparent from the embodiments described in detail later.

(B) Control Method and Control Program FIG. 12 shows a control method according to the second embodiment. In this control method, a motion assisting wearing tool 2 having an actuator 201 for applying power to the wearer 1 is worn on a person 1 (ST701), a biological signal of the wearer 1 is detected (ST702), and the wearer is placed. 1 and an optional command signal for causing the actuator 201 to generate power according to the intention of the wearer 1 by using the detected biological signal. (ST704), and by comparing the detected physical quantity with the reference parameters of each phase of each task stored in the database 6 (ST705 to 707), the task of the wearer 1 and its phase are estimated, A hybrid ratio (optional command signal / autonomous command signal) corresponding to the phase of this task is defined (ST708). An autonomous command signal for generating power corresponding to the actuator 201 is generated (ST709), and an arbitrary command signal and an autonomous command signal are combined to generate a total command signal so that a specified hybrid ratio is obtained. (ST710), the actuator 201 is driven by supplying the current generated in response to the total command signal (ST711).

  ST701 to 703 are the same as ST601 to 603 in the example of the first embodiment shown in FIG. 10, and ST705 to 708 are the same as ST607 to 610 in the example of the first embodiment shown in FIG. Further, the step (ST704) of generating an optional command signal corresponding to the biological signal is preferably composed of ST604 to 606a shown in FIG.

  The optional command signal is preferably used to generate a pulse current corresponding to the nerve transmission signal and a driving current corresponding to the myoelectric potential signal, as in the first embodiment. The hybrid ratio is set in advance so as to assist the operation of the wearer 1 without a sense of incongruity for each phase of each task, and is stored in the database 6. The hybrid ratio is automatically defined by the control device 20A as described above when the phase is estimated by comparing the actually measured physical quantity with the reference parameter. As a result, a total command signal is generated so as to have a required hybrid ratio, and by applying power according to the total command signal, operation assistance corresponding to various operations can be smoothly performed.

  In order to execute the above-described control, a process for detecting a biological signal of the wearer 1 (ST702), a process for detecting a physical quantity of the human machine system 10 composed of the wearer 1 and the motion assisting wearing tool 2 (ST703), and detection A process of generating an optional command signal for causing the actuator 201 to generate motive power according to the intention of the wearer 1 using the biometric signal thus obtained (ST704), and the detected physical quantity and the reference parameter of each phase of each task. By comparing (ST705 to 707), the phase of the task of the wearer 1 is estimated, a process for defining a hybrid ratio corresponding to this phase (ST708), and power corresponding to this phase is generated in the actuator 201. Processing to generate an autonomous command signal (ST709) and an optional instruction to achieve a specified hybrid ratio A process of generating a total command signal by combining the signal and the autonomous command signal (ST710), and a process of driving the actuator 201 by supplying a current generated according to the generated total command signal (ST711) The control program is stored in the storage device of the control device 20B of the wearable movement assist device.

  FIG. 13 shows another example of the wearable movement assist device of the second embodiment. The wearable movement assisting device includes a movement assisting wearing tool 2 having an actuator 201 that applies power to the wearer 1, a biological signal sensor 221 that detects a biological signal of the wearer 1, and an operation of the wearer 1. Using the physical quantity sensor 13 for detecting the physical quantity related to the sensor and the biological signal detected by the biological signal sensor 221, a command signal (optional command signal) for causing the actuator 201 to generate power according to the intention of the mounting 1 is generated. Optional control means 24, database 6 storing each reference parameter of a series of minimum operation units (phases) constituting each operation pattern of wearer 1 classified as a task, physical quantity detected by physical quantity sensor 13, and The operation pattern of the wearer 1 is estimated by comparing with the reference parameter, and the power corresponding to the operation pattern is applied to the actuator 20. Are synthesized by an autonomous control means 7 that generates a command signal (autonomous command signal) for generating the command signal, a command signal synthesis means 8 that synthesizes an optional command signal and an autonomous command signal, and a command signal synthesis means 8. Drive current generation means 5 that generates a current corresponding to the total command signal and supplies the current to the actuator 201.

  It is preferable to acquire a nerve transmission signal for operating the musculoskeletal system of the wearer 1 and a myoelectric potential signal accompanying the muscle activity from the biological signal. For this, the same biological signal processing means 3 ( Although two are shown in FIG. 13, one may be used), and the description thereof will be omitted. The database 6, the autonomous control means 17, the signal synthesis means 8, and the drive current generation means 5 can be the same as those shown in FIG. The optional control means 24 and the autonomous control means 17 compare the physical quantity detected by the physical quantity sensor 13 with the reference parameter stored in the database 6, thereby determining the phase of the task that the wearer 1 is to perform. It has a function to estimate and generate an optional command signal and an autonomous command signal so as to obtain a hybrid ratio and a power assist rate according to this phase.

  FIG. 14 and FIG. 15 show a preferred example of the control method of the wearable movement assist device. In this control method, a motion assisting wearing tool 2 having an actuator 201 for applying power to the wearer 1 is worn on a person 1 (ST801), a biological signal of the wearer 1 is detected (ST802), and the wearer is placed. The physical quantity of the human machine system 10 including 1 and the motion assisting wearing device 2 is detected (ST803), an optional command signal corresponding to the detected physical quantity is generated (ST804), and the detected physical quantity and stored in the database 6 By comparing the reference parameters of each phase (ST805 to 807), the phase of the task that the wearer 1 is going to perform is estimated, and the hybrid ratio and the power assist rate corresponding to this phase are specified (ST808). Then, an autonomous command signal for driving the actuator 201 with power according to this phase is generated (ST809). Then, an optional command signal and an autonomous command signal are synthesized so as to obtain a prescribed hybrid ratio and power assist rate, and a total command signal is generated (ST810), and an actuator is generated by supplying a current generated according to the total command signal. 201 is driven (ST811).

In order to execute the above-described control, a process of detecting a biological signal of the wearer 1 (ST802), a process of detecting a physical quantity of the human machine system 10 including the wearer 1 and the motion assisting wearing tool 2 (ST803), and detection Using the biological signal thus generated, a process (ST804) for generating an optional command signal for causing the actuator 201 to generate power according to the intention of the wearer 1 is compared with the detected physical quantity and the reference parameter of each phase. (ST805 to 807) to estimate the phase that the wearer 1 is going to perform, and to define the hybrid ratio and the power assist rate corresponding to this task phase (ST808), and according to the phase of this task A process (ST809) for generating an autonomous command signal for causing the actuator 201 to generate power, and Processing to generate a total command signal by combining an arbitrary command signal and the autonomous command signal so as to obtain a hybrid ratio and a power assist rate (ST810), and supply of a current generated according to the generated total command signal The control program for performing the process of driving the actuator 201 (ST811) is stored in the storage device of the control device 20C of the wearable motion assisting device.
[3] Other functions Drive control at start-up (1) In case of reflex action For example, if it is pushed suddenly from the back, it will fall down as it is, so you must support your body with one foot in a reflective manner. . However, if the control is performed such that one leg is simply moved forward, one foot is suddenly pushed forward, so that the wearer instinctively pushes one leg and makes the movement of pushing one leg forward awkward. In such a case, as shown in FIG. 16, the current 92 in the opposite direction is supplied for a very short time (about 0.01 to 0.3 seconds) immediately before supplying the current 91 for driving the actuator 201 in the operation direction. When the actuator 201 is driven in the opposite direction, the wearer 1 tries to put one foot forward in a reflective manner, and the operation is rather smooth. Such control using reflexes cannot be performed by a normal robot, and is effective for the first time when the wearer 1 wears the wearable movement assist device of the present invention.
(2) In the case of normal movement Even in the case of normal movement such as walking, if you perform autonomous control that raises your foot, you may feel as if your foot has been suddenly pressed. In order to remove such a sense of incongruity, it is possible to smoothly drive the actuator 201 in the opposite direction by supplying the current 92 in the opposite direction at the start, and then supply the current 91 to drive the actuator 201 in the operation direction. Can move smoothly.

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.
Example 1
This example is for showing the effect of the first embodiment. A condition in which the nerve transmission signal is used as a trigger signal when the wearer is relaxed and sitting on a chair and the knee joint is extended (FIG. 17), and a condition in which the nerve transmission signal is not used as a trigger signal; That is, the torque of the knee actuator 201b was measured under the condition of supplying only the drive current corresponding to the myoelectric potential signal to the actuator 201b (FIG. 18).

In the case of the former condition, a torque was obtained by superimposing a pulse current of a predetermined magnification corresponding to the nerve transmission signal on the tip of the torque obtained from the measured biological signal. The start of the change in the knee rotation angle θ was 0.2 seconds after the detection of the biological signal. On the other hand, in the case of the latter condition, the torque with the waveform of the biological signal was obtained. Since the rise of this torque is gentle, it took 0.3 seconds from the detection of the biological signal until the change of the knee rotation angle θ started. From these results, it can be seen that by using the nerve transmission signal as a trigger signal and generating a pulse current (rectangular wave) having a predetermined width at the tip of the biological signal, the drive of the actuator 201b can be started quickly.
Example 2
This example is for showing the effect of the second embodiment. The case where a wearer is powered by a combination of autonomous control and voluntary control is shown in which the wearer stands up from a sitting state. (C) of FIG. 19 shows the torque of the knee actuator according to the command signal by autonomous control, (d) shows the torque of the knee actuator according to the command signal by optional control, and (e) shows the autonomous control. The torque of the knee actuator in accordance with the total command signal obtained by synthesizing the command signal by and the command signal by optional control is shown. 19A shows the phase number, and FIG. 19B shows the knee rotation angle θ.

  FIG. 20 shows a case where power is applied by a combination of autonomous control and voluntary control when the wearer sits down after sitting up in a chair and then standing up. Also in the case of FIG. 20, (a) shows the phase number, and (b) shows the knee rotation angle θ.

  As apparent from the graph of FIG. 19 (e), the actual knee actuator torque increased rapidly at the rise of phase 2 and rapidly decreased at the fall of phase 3. At the tip of Phase 2 corresponding to the rise from the chair, the torque suddenly increased, so the knee actuator started to rotate without delay to the wearer's intention, and the wearer had a sufficient power assist feeling and no discomfort. I was able to start up. Also, at the fall of Phase 3, the torque by autonomous control quickly becomes 0, thereby preventing the situation where the wearer is inadvertently forced to push out the wearer and preventing the wearer from feeling uncomfortable. Can be suppressed. As a result, in all the processes of Phases 1 to 4, the wearer had a sufficient power assist feeling and was able to operate smoothly without a sense of incongruity.

  On the other hand, the torque according to the command signal by the optional control shown in FIG. 19D does not rise sufficiently, so that the knee actuator cannot be started as quickly as possible. Further, the torque according to the command signal by the autonomous control shown in FIG. 19C, that is, a certain amount of torque is different from the torque that changes in the process of operation, and therefore, a series of smooth operations without any sense of incongruity is performed. I can't. That is, it can be seen that only a combination of the above-described voluntary control and autonomous control can provide both a quick start and a torque that matches the wearer's movement.

  On the other hand, when sitting immediately after standing up, the torque increased sharply at the tip of phase 2 corresponding to the standing up from the chair, as is apparent from the graph of FIG. The wearer started to turn without delay, and the wearer had a sufficient power assist feeling and was able to stand up without feeling uncomfortable. In the middle of Phase 3, the generation of biological signals is suppressed, so the torque due to voluntary control is reduced, and even if the torque in the rising direction due to autonomous control is added, the effect is offset and the overall torque is reduced. Was not big enough to make you feel uncomfortable when sitting in a chair. As a result, even if the operation (task) is suddenly changed, the wearer has a sufficient power assist feeling and can operate smoothly without a sense of incongruity.

  On the other hand, with the torque according to the command signal by the optional control shown in FIG. 20 (d), the start-up is insufficient, so that the knee actuator cannot be started as quickly as possible. Further, when the torque according to the command signal by autonomous control shown in (c) of FIG. 20 is suddenly changed from phase 3 to phase 1, a constant torque acts in the direction of hindering the operation, and there is a sense of incongruity. Thus, it can be seen that even when the operation is not performed in a series of operations suddenly, a sense of incongruity can be suppressed by the combination of the above-described optional control and autonomous control.

  Although the present invention has been described in detail with reference to the above embodiments and examples, the present invention is not limited thereto, and various modifications can be made within the scope of the technical idea of the present invention.

It is the schematic which shows the whole structure of a mounting | wearing type movement assistance apparatus. It is a perspective view which shows a movement assistance mounting tool. It is a block diagram which shows the mounting | wearing type movement assistance apparatus of 1st embodiment. It is the schematic which shows an example of a structure of a biological signal processing means, and a process of the biological signal (the nerve transmission signal and myoelectric potential signal have isolate | separated) by it. It is the schematic which shows the other example of a process of the structure of a biological signal processing means, and the biological signal (a nerve transmission signal and a myoelectric potential signal are superimposed) by it. It is a flowchart which shows the control method of 1st embodiment. It is the schematic which shows an example of the drive current obtained from the biosignal which the nerve transmission signal and the myoelectric potential signal have isolate | separated. It is the schematic which shows the other example of the drive current obtained from the biosignal in which the nerve transmission signal and the myoelectric potential signal are superimposed. It is a block diagram which shows the example which controls a power assist rate in the mounting | wearing type movement assistance apparatus of 1st embodiment. It is the schematic which shows the example of a task and a phase. It is the schematic which shows the estimation method of the task and phase which were stored in the database. It is a flowchart for demonstrating control of a power assist rate in the control method of 1st embodiment. It is a block diagram which shows the mounting | wearing type movement assistance apparatus of 2nd embodiment. It is a flowchart which shows the control method of 2nd embodiment. It is a block diagram which shows the example which controls a power assist rate in the mounting | wearing type movement assistance apparatus of 2nd embodiment. It is a flowchart for demonstrating control of a power assist rate in the control method of 2nd embodiment. It is a block diagram which shows the structure of a control apparatus. It is the schematic which shows another example of improvement of drive current generation. It is a graph which shows the torque of a knee actuator at the time of adding the pulse current according to the nerve transmission signal in Example 1. It is a graph which shows the torque of a knee actuator in the case where the pulse current according to a nerve transmission signal is not added in Example 1. It is a graph which shows an example of the torque of the knee actuator obtained by control which synthesizes an arbitrary command signal and an autonomous command signal in Example 2. It is a graph which shows another example of the torque of the knee actuator obtained by control which synthesize | combines an arbitrary command signal and an autonomous command signal in Example 2. FIG.

Explanation of symbols

1 ... Human (wearer)
2 ... Motion assisting device 3 ... Biological signal processing means 4, 14, 24 ... Optional control means 5 ... Drive current generating means 6 ... Databases 7, 17 ... Autonomous control Means 8 ... Signal synthesizing means 10 ... human machine system 13 ... physical quantity sensors 20, 20A, 20B, 20C ... control device 21 ... power source 201 ... actuator 202 ... arm 203 ..Joint 221 ... Biological signal sensor 222 ... Barycentric sensor

Claims (12)

A wearable movement assist device that assists or acts on behalf of the wearer,
An operation assisting wearing device having an actuator for applying power to the wearer;
A biological signal sensor for detecting a biological signal of the wearer;
A physical quantity sensor for detecting a physical quantity related to the movement of the wearer;
Optional control means for generating a command signal for causing the actuator to generate power according to the intention of the wearer, using a biological signal detected by the biological signal sensor;
A database that stores reference parameters for each of a series of minimum motion units (phases) constituting the motion pattern of the wearer classified as a task;
A command for estimating a phase of the wearer's task by comparing a physical quantity detected by the physical quantity sensor with a reference parameter stored in the database, and causing the actuator to generate power corresponding to the phase. An autonomous control means for generating a signal;
A signal synthesis means for synthesizing a command signal from the optional control means and a command signal from the autonomous control means;
A mounting-type motion assisting device, comprising: drive current generating means for generating a total current corresponding to the total command signal synthesized by the signal synthesizing means and supplying the total current to the actuator. The wearable motion assist device according to claim 1,
The database stores the ratio (hybrid ratio) between the command signal from the optional control means and the command signal from the autonomous control means so as to have a required correspondence with the reference parameter of the phase,
The signal synthesizing unit is configured to output a command signal from the voluntary control unit and the autonomous unit so that a hybrid ratio defined based on the correspondence relationship is obtained according to a task phase estimated by the autonomous control unit. A wearable motion assisting device that synthesizes a command signal from a control means. In the wearing type movement auxiliary device according to claim 1 or 2,
A biological signal processing means for acquiring a nerve transmission signal for operating the wearer's musculoskeletal system and a myoelectric potential signal accompanying muscle activity from a biological signal detected by the biological signal sensor;
The drive-type motion assisting device, wherein the drive current generating unit starts the operation of the actuator by supplying a pulse current generated according to a nerve transmission signal acquired by the biological signal processing unit. In the wearing type movement auxiliary device according to claim 3,
The drive current generating means generates the pulse current or the total current so as to be larger than a lower limit value of a current capable of driving the actuator when supply of current to the actuator is started. Wearable motion assist device. In the wearing type movement auxiliary device according to any one of claims 1 to 4,
The database stores the reference parameters of each phase and the power application rate (power assist rate) by the actuator so as to have a required correspondence relationship,
The signal synthesizing means defines a power assist rate according to the phase of the task estimated by the autonomous control means based on the correspondence relationship, and commands from the optional control means so as to be the power assist rate. A wearable motion assisting device that synthesizes a signal and a command signal from the autonomous control means. In the wearing type movement auxiliary device according to any one of claims 1 to 5,
The drive current generating means supplies a current for driving the actuator in a direction opposite to the operation for a predetermined time when the wearer operates by reflexes, and then moves the actuator in the operation direction. A wearable motion assisting device that supplies a current for driving. A method of controlling a wearable motion assist device that assists or substitutes for a wearer's motion,
In a state where an operation assisting wearing device having an actuator for applying power to the wearer is worn by the wearer,
Detecting physical quantities of the wearer's biological signal and the wearer's motion,
Using the detected biological signal, generate an optional command signal for causing the actuator to generate power according to the wearer's intention,
The phase of the task that the wearer is going to perform is estimated by comparing the detected physical quantity with the reference parameters of each of a series of minimum movement units (phases) that constitute the movement pattern of the wearer classified as a task. , Generating an autonomous command signal for causing the actuator to generate power according to this phase,
Combining these generated voluntary command signals and autonomous command signals,
A method for controlling a wearable motion assisting device, wherein a current corresponding to the synthesized total command signal is generated and supplied to the actuator. In the control method of the wearing type movement auxiliary device according to claim 7,
A ratio (hybrid ratio) between the voluntary command signal and the autonomous command signal is set in advance so as to have a required correspondence with each reference parameter of the phase, and according to the estimated task phase A control method for the wearable motion assisting device, wherein the hybrid ratio is defined based on the correspondence relationship, and the total command signal is synthesized so as to be the hybrid ratio. In the control method of the wearing type movement auxiliary device according to claim 8,
When the supply of the current to the actuator is started, the pulse current or the total current is supplied so that the pulse current or the total current is larger than a lower limit value of a current capable of driving the actuator. Control method. In the control method of the wearing type movement auxiliary device according to any one of claims 7 to 9,
A power ratio (power assist rate) to be given to the wearer is set in advance so as to have a required correspondence relationship with each reference parameter of the phase, and a power assist rate corresponding to the estimated task phase is set. A control method for a wearable motion assisting device, which is defined based on the correspondence relationship and synthesizes the total command signal so as to achieve this power assist rate. In the control method of the wearing type movement auxiliary device according to any one of claims 7 to 10,
When the wearer operates by reflexes, the actuator is driven in the direction of the operation after generating a drive current for driving the actuator in a direction opposite to the operation for a predetermined time. Control method for a wearable motion assist device. A program for causing a computer for controlling the wearable motion assisting device to execute the control method according to any one of claims 7 to 11.

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