JPWO2017017809A1 - Knee joint control method and lower limb orthosis - Google Patents

Abstract

The knee joint control method of the present invention measures at least one of the knee flexion moment M1 and ankle plantar flexion moment M2 of the user and shifts from a state not satisfying the following expression (1) to a satisfied state, or Step A for increasing the braking force against the rotation of the knee joint when transitioning from a state that does not satisfy the following expression (2) to a state that satisfies the following equation: M1> C1 (1) M2> C2 (2) When shifting from a state not satisfying the following equation (3) to a satisfying state, or when shifting from a state not satisfying the following equation (4) to a satisfying state, the braking force against the rotation of the knee joint is more than the step A. A step B of reducing. M1 <C3 (3) M2 <C4 (4) However, C1 to C4 are constants, and C1 ≧ C3 ≧ 0 and C2 ≧ C4 ≧ 0.

Description

  The present invention relates to a method for assisting walking by adjusting a braking force against rotation of a knee joint during walking, and a lower limb orthosis for assisting walking.

  When walking, a person usually adjusts the braking force against the rotation of the knee joint in unconsciousness according to the walking cycle. On the other hand, when the movement of the ankle, knee, hip, etc. cannot be controlled by stroke due to hemiplegia, old age, etc., the knee joint can be arbitrarily fixed and released regardless of the walking cycle. Ordinarily, walking is assisted by a knee joint attached to an artificial knee.

  For this reason, although there are few products that have been commercialized, a method to control the movement of the knee joint based on data such as moment and acceleration around the knee joint acquired by sensors attached to the lower limb orthosis and artificial knee is currently under investigation Has been. For example, in US Pat. No. 6,057,049, at least two moments, or one moment and one force, or two moments and one force, or two forces and one moment, are detected by a sensor. Prosthetic knee joint that determines sensor data and combines sensor data of at least two of the determined values with each other by mathematical manipulation and calculates auxiliary variables based on control of flexion resistance and / or extension resistance The control method is described. Specifically, Patent Document 1 describes that the distance between the force vector and the shaft at the reference height, the section moment or the section force at the reference height can be determined as auxiliary variables.

Special table 2013-510605 gazette

The artificial knee control method described in Patent Document 1 adds, multiplies, subtracts, or divides mathematical data such as knee moment and heel moment obtained from a sensor to obtain a sectional moment, a sectional force, Auxiliary variables such as force or distance are calculated and the values of bending resistance and extension resistance are adjusted using these auxiliary variables, so the control method is complex, and both detection of various data and control of resistance values are performed. It was difficult to do in real time.
Therefore, an object of the present invention is to provide a knee joint control method and a lower limb orthosis capable of appropriately and easily adjusting the braking force with respect to the rotation of the knee joint in accordance with the gait of the user.

The knee joint control method that has solved the above problem is to measure at least one of the user's knee flexion moment M1 and ankle plantar flexion moment M2 and shift from a state that does not satisfy Equation (1) to a satisfied state. Or a step A for increasing the braking force against the rotation of the knee joint when transitioning from a state not satisfying the expression (2) to a state satisfying the equation (2),
M1> C1 (1)
M2> C2 (2)
The step of reducing the braking force against the rotation of the knee joint as compared with step A when the state transitions from the state not satisfying the expression (3) to the state satisfied or from the state not satisfying the expression (4) to the state satisfied. And a point including B.
M1 <C3 (3)
M2 <C4 (4)
However, C1 to C4 are constants, and C1 ≧ C3 ≧ 0 and C2 ≧ C4 ≧ 0.

  In the knee joint control method of the present invention, when the transition from the state not satisfying the equation (1) to the state satisfying the equation (2) or the transition from the state not satisfying the equation (2) to the state satisfying is performed. This corresponds to the start of the initial stance. For this reason, it is possible to estimate the start time in the initial stage of stance by determining whether the state has shifted from the state not satisfying the expression (1) or (2) to the state satisfying. At this time, it becomes difficult to bend or extend the knee joint by increasing the braking force against the rotation of the knee joint.

  On the other hand, the transition from the state not satisfying the expression (3) to the state satisfying or the transition from the state not satisfying the expression (4) to the state satisfying corresponds to the start of the middle stance phase of the walking cycle. . For this reason, it is possible to estimate the start time of the middle stance by determining whether the state has shifted from the state not satisfying the expression (3) or the expression (4) to the state satisfying the expression. At this time, it becomes easy to bend or extend the knee joint by reducing the braking force against the rotation of the knee joint.

  In other words, the knee joint control method of the present invention can easily estimate the walking cycle by comparing at least one of the knee flexion moment M1 and the ankle plantar flexion moment M2 with the predetermined values C1 to C4. . In addition, since the knee joint control method of the present invention does not require complicated control, it is possible to estimate the walking cycle and adjust the braking force against the rotation of the knee joint in real time.

The knee joint control method of the present invention is more effective than the step B when the transition from the state not satisfying the equation (5) to the satisfied state or the transition from the state not satisfying the equation (6) to the satisfied state. It is preferable to include step C for increasing the braking force against the rotation of the joint.
M1> C5 (5)
M2> C6 (6)
However, C5 to C6 are constants, and C5 ≧ C3 ≧ 0 and C6 ≧ C4 ≧ 0.
The transition from the state that does not satisfy the expression (5) to the state that satisfies the condition, or the transition from the state that does not satisfy the expression (6) to the state that satisfies the condition corresponds to the start of the stance end in the walking cycle. For this reason, it is possible to estimate the start time of the stance end by determining whether the state has shifted from the state not satisfying the expression (5) or (6) to the state satisfying. At this time, it becomes difficult to bend or extend the knee joint by increasing the braking force against the rotation of the knee joint.

  In step A, the braking force against the rotation of the knee joint is increased when the transition from the state not satisfying the equation (1) to the state satisfying the equation and the transition from the state not satisfying the equation (2) to the state satisfied. In Step B, when the transition from the state not satisfying the expression (3) to the state satisfying the expression and when the transition from the state not satisfying the expression (4) to the state satisfying is made, the braking force against the rotation of the knee joint is reduced. In step C, the braking force against the rotation of the knee joint when the transition from the state not satisfying the equation (5) to the satisfied state and the transition from the state not satisfying the equation (6) to the satisfied state is made. It is preferable to enlarge it. By using both the knee flexion moment M1 and the ankle plantar flexion moment M2, the estimation accuracy of the walking cycle can be improved, so that the timing accuracy for adjusting the braking force against the rotation of the knee joint can be improved.

  In Step C, a predetermined delay time (a third delay time to be described later) is entered after a transition from a state that does not satisfy the expression (5) to a state that satisfies the condition, or a state that does not satisfy the condition of the expression (6). It is preferable to increase the braking force with respect to the rotation of the knee joint after Step B). By providing the delay time in this way, the timing for adjusting the braking force against the rotation of the knee joint can be set in accordance with the gait of the user.

  In step B, it is preferable to increase the braking force against the rotation of the knee joint in step A after a predetermined time (second predetermined time described later) has elapsed since the braking force against the rotation of the knee joint has been reduced. This makes it possible to exclude the peaks of knee flexion moment M1 and ankle joint bottom flexion moment M2 that are unnecessary for the control of the knee joint, which may occur at the end of the stance. As a result, since the estimation accuracy of the walking cycle can be improved, the accuracy of the timing for adjusting the braking force against the rotation of the knee joint is increased.

Measure the acceleration A associated with the user's movement, and in step A, shift from a state not satisfying the equation (1) to a satisfied state, or shift from a state not satisfying the equation (2) to a satisfied state, and It is preferable to increase the braking force with respect to the rotation of the knee joint when the state is shifted from the state not satisfying the expression (7) to the state satisfied.
A> C7 (7)
However, C7 is a constant and C7> 0.
In the knee joint control method of the present invention, by using the acceleration A, it is possible to improve the estimation accuracy of the start time in the initial stage of the stance, so that the accuracy of the timing for adjusting the braking force against the rotation of the knee joint can be improved.

  In step B, a predetermined delay time (second delay time described later) is obtained after shifting from a state not satisfying the expression (3) to a state satisfying the expression, or from a state not satisfying the expression (4) to a state satisfying. After the elapse of time, it is preferable to make the braking force with respect to the rotation of the knee joint smaller than the step A. By providing the delay time in this way, the timing for adjusting the braking force against the rotation of the knee joint can be set in accordance with the gait of the user.

In addition, the lower limb orthosis that can solve the above-mentioned problems are: a first component member on the thigh side, a second component member on the lower leg side, a knee rotation member that holds the first component member and the second component member, A knee brace moment M1 at the center of rotation of the knee rotation member; the knee flexion moment M1 satisfies the formulas (1), (3), and (5) A processing unit for determining the condition; when the transition from the state not satisfying the equation (1) to the state satisfying the equation (1), the braking force for the rotation of the knee rotating member is increased, and the state satisfying the equation (3) is satisfied. When the transition is made, the braking force against the rotation of the knee rotation member is made smaller than the braking force when the transition from the state not satisfying the equation (1) to the satisfied state is satisfied, and the state satisfying from the state not satisfying the equation (5) Against the rotation of the knee rotation member when A driving unit to be larger than the braking force of the braking force (3) when a transition to a state that satisfies a condition that does not satisfy equation that, it is an gist points are provided.
M1> C1 (1)
M1 <C3 (3)
M1> C5 (5)
However, C1, C3, and C5 are constants, and C1 ≧ C3 ≧ 0 and C5 ≧ C3 ≧ 0.

  Since the lower limb orthosis of the present invention is provided with the measurement unit, the knee flexion moment M1 at the rotation center of the knee rotation member can be measured. The transition from the state not satisfying the expression (1) to the state satisfying the expression corresponds to the start of the initial stance in the walking cycle. For this reason, it is possible to estimate the start time of the initial stance by determining whether or not the state has shifted from the state not satisfying the expression (1) to the state satisfied. At this time, it becomes difficult to bend or extend the knee joint by increasing the braking force against the rotation of the knee joint.

  In the present invention, the transition from the state that does not satisfy the expression (3) to the state that satisfies the condition corresponds to the start of the middle stance phase of the walking cycle. For this reason, it is possible to estimate the start time of the middle stance by determining whether the state has shifted from the state not satisfying the expression (3) to the state satisfied. By making the braking force against the rotation of the knee joint smaller than the braking force when shifting from the state not satisfying the expression (1) to the state satisfying the expression (1) in the middle stance phase, the knee joint can be easily bent or extended.

  In the present invention, the transition from the state not satisfying the expression (5) to the state satisfying the expression corresponds to the start of the end of the stance in the walking cycle. For this reason, it is possible to estimate the start time of the stance end by determining whether the state has shifted from the state not satisfying the expression (5) to the state satisfied. By making the braking force against the rotation of the knee joint larger than the braking force when the state shifts from the state not satisfying the expression (3) to the state satisfying at the end of the stance, it becomes difficult for the knee joint to bend or extend.

  Therefore, the lower limb orthosis of the present invention can easily estimate the walking cycle by comparing the knee flexion moment M1 with the predetermined values C1, C3, and C5. For this reason, the adjustment of the braking force with respect to the rotation of the knee joint can be easily performed in real time.

The lower limb orthosis of the present invention has a third component member on the ankle joint side, an ankle rotation member that holds the second component and the third component; a foot at the rotation center of the ankle rotation member in the measurement unit The joint bottom flexion moment M2 is measured: In the processing unit, the following expressions (1), (3), (5), the following expressions (2), (4), and (6) are satisfied. In the drive unit, when the transition from the state not satisfying the equation (1) to the state satisfying the equation (2) or from the state satisfying the equation (2) to the state satisfying the equation (2), The braking force is increased; when the transition from the state not satisfying the expression (3) to the state satisfying the expression (4) or the transition from the state not satisfying the expression (4) to the state satisfying is satisfied, Satisfy power from a state that does not satisfy equation (1) Or less than the braking force when transitioning from a state not satisfying equation (2) to a state satisfying equation (2); when shifting from a state not satisfying equation (5) to a state satisfying, or ( 6) When shifting from a state not satisfying the expression to a state satisfying the expression, when the braking force against the rotation of the knee rotating member is shifted from a state not satisfying the expression (3) to a state satisfying the expression, or (4) It is preferable to make it larger than the braking force when shifting from the unsatisfied state to the satisfied state.
M2> C2 (2)
M2 <C4 (4)
M2> C6 (6)
However, C2, C4, and C6 are constants, and C2 ≧ C4 ≧ 0 and C6 ≧ C4 ≧ 0.
In this way, by using both the knee flexion moment M1 and the ankle plantar flexion moment M2 for controlling the knee joint, it is possible to improve the estimation accuracy of the walking cycle, and thus adjust the braking force against the rotation of the knee joint. Timing accuracy can be improved.

  In the lower limb orthosis of the present invention, the processing unit is preferably provided in an external terminal capable of communicating with the measurement unit and the drive unit. If the processing unit is provided in the external terminal, doctors other than the user can observe the data measured by the measurement unit, and C1 to C6 described on the right side of the equations (1) to (6). Changes can be made remotely.

The knee joint control method of the present invention can easily estimate the walking cycle by using at least one of the knee flexion moment M1 and the ankle plantar flexion moment M2. In addition, since complicated control is unnecessary, it is possible to estimate the walking cycle and adjust the braking force against the rotation of the knee joint in real time.
Furthermore, the lower limb orthosis of the present invention can easily estimate the walking cycle by using the knee bending moment M1. In addition, since complicated control is unnecessary, it is possible to estimate the walking cycle and adjust the braking force against the rotation of the knee joint in real time.

The schematic diagram which shows a knee flexion moment and an ankle plantar flexion moment is represented. 3 is a flowchart illustrating a knee joint control method according to Embodiment 1 of the present invention. 7 is a flowchart illustrating a knee joint control method according to Embodiment 2 of the present invention. 7 is a flowchart illustrating a knee joint control method according to Embodiment 3 of the present invention. 7 is a flowchart illustrating a knee joint control method according to Embodiment 4 of the present invention. 7 is a flowchart illustrating a knee joint control method according to a fifth embodiment of the present invention. 1 represents a perspective view of a lower limb orthosis of the present invention. 1 represents a perspective view of a lower limb orthosis of the present invention. The block diagram which shows the structural example of the lower limbs orthosis of this invention is represented. The block diagram which shows the other structural example of the leg brace of this invention is represented. The block diagram which shows the other structural example of the leg brace of this invention is represented. The block diagram which shows the other structural example of the leg brace of this invention is represented.

  Hereinafter, the present invention will be described in more detail based on the following embodiments, but the present invention is not limited by the following embodiments as a matter of course, and appropriate modifications are made within a range that can meet the purpose described above and below. In addition, it is of course possible to carry out them, all of which are included in the technical scope of the present invention. Note that the dimensions of the various members in the drawings give priority to the understanding of the features of the present invention, and may differ from the actual dimensions.

1. Knee Joint Control Method The knee joint control method of the present invention measures at least one of the user's knee flexion moment M1 and ankle joint sole flexion moment M2, and shifts from a condition not satisfying the equation (1) to a satisfied condition. Or a step A for increasing the braking force against the rotation of the knee joint when transitioning from a state not satisfying the expression (2) to a state satisfying the equation (2),
M1> C1 (1)
M2> C2 (2)
The step of reducing the braking force against the rotation of the knee joint as compared with step A when the state transitions from the state not satisfying the expression (3) to the state satisfied or from the state not satisfying the expression (4) to the state satisfied. B.
M1 <C3 (3)
M2 <C4 (4)
However, C1 to C4 are constants, and C1 ≧ C3 ≧ 0 and C2 ≧ C4 ≧ 0.

  In the knee joint control method of the present invention, it is possible to estimate the start time of the initial stance by determining whether or not the transition from the state not satisfying the expression (1) or (2) is satisfied in step A. it can. Further, by increasing the braking force against the rotation of the knee joint in the initial stage of the stance, it becomes difficult to bend or extend the knee joint. On the other hand, it is possible to estimate the start time of the middle stance by determining whether or not the transition from the state not satisfying the expression (3) or (4) to the state satisfying in the step B is made. Further, by reducing the braking force against the rotation of the knee joint in the middle stance phase, the knee joint can be easily bent or extended. In other words, the knee joint control method of the present invention can easily estimate the walking cycle by comparing at least one of the knee flexion moment M1 and the ankle plantar flexion moment M2 with the predetermined values C1 to C4. . In addition, since the knee joint control method of the present invention does not require complicated control, it is possible to estimate the walking cycle and adjust the braking force against the rotation of the knee joint in real time.

  FIG. 1 is a schematic diagram showing a knee flexion moment M1 and an ankle plantar flexion moment M2. When the sole is in contact with the floor 13, a floor reaction force F1 is generated in the lower limb 10. When the knee joint 11 comes to the front side of the center of gravity 12, a knee reaction moment F1 is generated in the direction in which the knee bends (the direction in which the thigh and the lower leg approach each other with the knee joint 11 as the rotation center) in response to the floor reaction force F1. The knee flexion moment M1 is represented by M1 = F1 × L1. Note that L1 is a perpendicular distance from the knee joint 11 to the floor reaction force F1.

  When the floor reaction force F1 passes forward of the ankle joint 10, the ankle joint 10 receives a moment due to the floor reaction force F1 in the dorsiflexion direction (the direction in which the toe moves away from the floor 13 with the ankle joint 10 as the rotation center). Then, in order to prevent the ankle joint 10 from rotating in the dorsiflexion direction, the ankle joint 10 acts in the plantar flexion direction (the direction in which the toes are brought closer to the floor 13 with the ankle joint 10 as the center), and the plantar flexor muscles F2 act. An ankle plantar flexion moment M2 is generated by the force F2. Ankle plantar flexion moment M2 is expressed by M2 = F2 × L2. Note that L2 is a perpendicular distance from the ankle joint 10 to the plantar flexor strength F2.

  In the present invention, at least one of the knee flexion moment M1 and the ankle plantar flexion moment M2 of the user is measured. The knee flexion moment M1 and the ankle plantar flexion moment M2 can be measured by, for example, a load cell (load converter) attached to a lower limb orthosis or a prosthesis, an electromyograph, or other known torque sensors.

  Examples of the load cell include a strain gauge type, a magnetostrictive type, a capacitance type, and a gyro type. For example, in the case of the strain gauge type, when a force or moment is applied to the strain generating body of the load cell, the electrical resistance value changes due to expansion and contraction of the strain gauge in the strain generating body, and this change is measured by voltage. Therefore, force and moment can be measured easily.

  If there are no severe obstacles such as paralysis with respect to the knee and ankle joint, an electromyograph can be used to measure the knee flexion moment M1 and ankle joint floor flexion moment M2. When the knee bending moment M1 is measured with an electromyograph, the electromyograph is attached to a muscle that bends the knee, such as the quadriceps. When measuring the ankle plantar flexion moment M2 with an electromyograph, the electromyograph is attached to the anterior tibial muscle or the like that generates the ankle plantar flexion moment when the ankle joint flexes. By processing the signal measured by the electromyograph into a state in which the magnitude can be compared by mathematical processing such as root mean square (RMS), information equivalent to the moment can be easily obtained.

  A knee joint control method according to an embodiment of the present invention will be described with reference to FIGS. 2 to 6 are flowcharts showing the knee joint control method according to the first to fifth embodiments of the present invention.

(Embodiment 1)
The first embodiment shown in FIG. 2 is an example in which the knee bending moment M1 is used to control the knee joint.

  When not walking, the braking force against the rotation of the knee joint is increased (step S1). By increasing the braking force against the rotation of the knee joint in this way, the knee joint can be fixed so that it does not flex or extend, or it can be flexed at a constant speed. Can be prevented from falling. In addition to the method of adjusting the magnitude of the braking force according to the knee bending moment as described above, the magnitude of the braking force is adjusted according to the acceleration of the knee joint that is measured separately. Also good. Note that the speed at which the knee joint bends or extends may be constant, or may be variable according to the speed at which the braking force against the rotation of the knee joint changes. The speed at which the knee joint bends or extends can be appropriately set according to the age, sex, gait, disease progression, etc. of the user. The speed at which the knee joint bends or extends can be similarly set in the case of steps A to C described later.

  As a method of increasing the braking force against the rotation of the knee joint, a method of applying a moment opposite to the knee bending moment M1 detected by a sensor such as a load cell, or a method of increasing the rotational torque of a knee joint attached to a lower limb orthosis or a prosthetic limb. Or the like can be used.

  In order to determine whether the user has started walking, it is determined whether a knee flexion moment M1 has occurred (step S2). Specifically, it is preferable to determine whether M1> 0.

  If the knee flexion moment M1 is generated in step S2, it is determined that walking is started, and a walking loop is started (step S3).

  If it is determined in step S2 that the knee bending moment M1 has not occurred, it can be determined that the walking has not started, so the process returns to step S1 in order to continue increasing the braking force against the rotation of the knee joint.

Next, it is determined whether the state has been shifted from a state not satisfying the expression (1) to a state satisfied (step S4). Thereby, the start time of the initial stage of stance can be estimated.
M1> C1 (1)
However, C1 is a constant and C1 ≧ 0.

  When shifting from the state not satisfying the expression (1) to the state satisfying, the braking force against the rotation of the knee joint is increased (step S5 (step A)). At this time, increasing the braking force against the rotation of the knee joint makes it difficult for the knee joint to bend or extend, so that the user can be encouraged to take a natural walking posture in the early stage of stance.

  In step S5, increasing the braking force with respect to the rotation of the knee joint means increasing the braking force with respect to the rotation of the knee joint as compared with step S8 described later. Specifically, increasing the braking force with respect to the rotation of the knee joint includes, for example, fixing the knee joint so that the knee joint does not bend or extend by applying the braking force with respect to the rotation of the knee joint, Applying a braking force causes the knee joint to bend or extend at a lower speed than step S8 (step B).

  In step S5, the braking force with respect to the rotation of the knee joint may be increased by maintaining the braking force that is increased when not walking in step S1.

  Although not shown in FIG. 2, after a predetermined delay time (first delay time) has elapsed since the transition from the state not satisfying the expression (1) to the state satisfying, the knee joint in step S <b> 5 (step A). It is preferable to increase the braking force against the rotation of the motor. By providing the first delay time, it is possible to set the timing for controlling the braking force against the rotation of the knee joint so as to match the gait of the user. The method of providing the first delay time in this way is particularly effective for a user whose knee position is not stable during walking. In general, the walking cycle is about 0.7 to 2.0 seconds, of which about 10% to 20% occupies the initial stance. For this reason, the first delay time can be set to 0.07 seconds to 0.2 seconds, for example.

  If the state does not change from the state not satisfying the expression (1) to the state satisfying, the braking force against the rotation of the knee joint is increased (step S6). If the knee flexion moment does not shift from the state that does not satisfy Equation (1) to the state that satisfies it, it is difficult to estimate at which stage of the walking cycle. At this time, by increasing the braking force against the rotation of the knee joint, it becomes difficult for the knee joint to bend or extend, so that the knee does not easily break.

  In step S6, the braking force against rotation of the knee joint may be increased by maintaining the increased braking force when not walking (step S1).

After step S5, it is determined whether the state has been shifted from a state not satisfying the expression (3) to a state satisfied (step S7). Thereby, the start time of the middle stance can be estimated.
M1 <C3 (3)
However, C3 is a constant, and C1 ≧ C3 ≧ 0. Further, C1> C3 ≧ 0 may be satisfied.

  When the state is shifted from the state not satisfying the expression (3) to the state satisfied, the braking force against the rotation of the knee joint is made smaller than the step S5 (step S8 (step B)). At this time, since the knee joint becomes easier to operate by reducing the braking force against the rotation of the knee joint than in step S5 (step A), it is possible to promote the user to take a natural walking posture in the middle of the stance.

  In step S8 (step B), reducing the braking force with respect to the rotation of the knee joint means, for example, releasing the fixation without applying the braking force with respect to the rotation of the knee joint or adding the braking force with respect to the rotation of the knee joint. The knee joint is bent or extended at a higher speed than S5 (Step A).

  As a method of reducing the braking force against the rotation of the knee joint, a method of reducing the moment applied in the opposite direction to the knee bending moment M1 detected by a sensor such as a load cell, a knee joint attached to a lower limb orthosis or a prosthetic limb is used. A method of reducing the rotational torque can be used.

  Although not shown in FIG. 2, in step S8 (step B), after a predetermined delay time (second delay time) has elapsed since the transition from the state not satisfying the expression (3) to the state satisfied, the step It is preferable to make the braking force against the rotation of the knee joint smaller than S5 (step A). By providing the second delay time, it is possible to set the timing for adjusting the braking force against the rotation of the knee joint so as to match the gait of the user. The method of providing the second delay time in this way is particularly effective for a user whose knee position is not stable during walking. In general, the middle stance accounts for about 10% to 20%. For this reason, the second delay time can be set to 0.07 seconds to 0.2 seconds, for example.

  If the state does not change from the state not satisfying the expression (3) to the state satisfying, the process returns to step S6 for increasing the braking force against the rotation of the knee joint. In step S6, the braking force for rotation of the knee joint may be increased by maintaining the braking force in step S1, and the braking force for rotation of the knee joint is maintained by maintaining the braking force in step S5. You may enlarge it.

  It is determined whether the elapsed time from the start of step S8 is within a first predetermined time (step S9). That is, it is determined whether or not the state in which the braking force with respect to the rotation of the knee joint is reduced is within the first predetermined time. Thereby, the presence or absence of occurrence of abnormal walking can be estimated.

  The first predetermined time can be set to 1.0 to 2.0 seconds, for example. The first predetermined time may be set to a time corresponding to one walking cycle of the user.

  When the elapsed time from the start of step S8 is within the first predetermined time, the process returns to step S4 for determining whether the state has shifted from the state not satisfying the expression (3) to the state satisfied. When the elapsed time from the start of step S8 is within the first predetermined time, it can be considered that the walking motion is continuing.

  When the elapsed time from the start of step S8 exceeds the first predetermined time, the braking force for the rotation of the knee joint is made larger than that in step S8 (step S10). If the elapsed time from the start of step S8 exceeds the first predetermined time, it can be considered that the walking motion has ended. Therefore, the braking force with respect to the rotation of the knee joint is set to be larger than that in step S8 so that knee bending does not occur. To do.

  In step S8 (step B), after a predetermined time (second predetermined time) has elapsed since the braking force for the rotation of the knee joint is reduced, in step S5 (step A), the braking force for the rotation of the knee joint is increased. It is preferable to do. This is intended for the case where, after step S8 (step B), the elapsed time from the start of step S8 is within the first predetermined time, and the process returns to step S4 in order to estimate the start time of the next stance initial stage. ing. Depending on the user, the knee flexion moment M1 or the ankle plantar flexion moment M2 may increase at the end of the stance, making it difficult to distinguish between the initial stance and the end stance. For this reason, in Step B, after the second predetermined time has elapsed since the braking force for the rotation of the knee joint is reduced, in Step A at the end of the next walking, the braking force for the rotation of the knee joint is increased, Peaks of knee flexion moment M1 and ankle plantar flexion moment M2 that occur in the middle of the stance phase and are unnecessary for knee joint control can be excluded, and the estimation accuracy of the walking cycle can be improved. Thereby, the precision of the timing which adjusts the braking force with respect to rotation of a knee joint is raised, and it can promote that a user takes a natural walking posture.

  The second predetermined time is preferably a time that is not less than half of the walking cycle. Peaks of knee flexion moment M1 and ankle plantar flexion moment M2 at the end of stance, which are not required for knee joint control, exceeded the half-walking period after the braking force against the knee joint rotation was increased in step S8 (step B). This is because it sometimes appears. In general, since the walking cycle is about 0.7 seconds to 2.0 seconds, the second predetermined time is set to, for example, not less than 0.35 seconds and not more than 1.0 seconds.

In the first embodiment, ankle joint flexion moment M2 can be used instead of knee flexion moment M1. In that case, the following formula (2) may be used instead of the formula (1) in step S4, and the following formula (4) may be used instead of the formula (3) in step S7.
M2> C2 (2)
M2 <C4 (4)
However, C2 and C4 are constants, and C2 ≧ C4 ≧ 0. Further, C2> C4 ≧ 0 may be satisfied.

  In the knee joint control method of the present invention, specific values of C1 to C4 are not particularly limited as long as the relationship of C1 ≧ C3 ≧ 0 and C2 ≧ C4 ≧ 0 is satisfied. , Sex, gait, disease progression, etc. can be set as appropriate. For example, C1 and C2 can be set in a range of 0N · m to 20N · m, and C3 and C4 can be set in a range of 0N · m to 5N · m.

(Embodiment 2)
In the second embodiment, in addition to the formulas (1) and (3) used in the first embodiment, an example using the formula (5) that can estimate the start time of the stance end stage is shown. FIG. 3 is a flowchart showing a knee joint control method according to Embodiment 2 of the present invention. Note that in the description of the second embodiment, the description overlapping with the above description is omitted.

  Steps S1 to S6 are the same as those in the first embodiment.

  After step S5 (step A), it is determined whether the state has shifted from the state not satisfying the expression (3) to the state satisfied (step S7). Thereby, the start time of the middle stance can be estimated.

  When the state is shifted from the state not satisfying the expression (3) to the state satisfied, the braking force against the rotation of the knee joint is made smaller than the step S5 (step S8 (step B)).

  If the transition from the state not satisfying the expression (3) to the state satisfying the equation is not made, the process returns to step S5 for increasing the braking force against the rotation of the knee joint.

After step S8, it is determined whether the state has been shifted from the state not satisfying the expression (5) to the state satisfied (step S11). Thereby, the start time of the stance end can be estimated.
M1> C5 (5)
However, C5 is a constant, and C5 ≧ C3 ≧ 0. Further, C5> C3 ≧ 0 may be satisfied.

  When the state transitions from the state not satisfying the expression (5) to the state satisfied in step S11, the process returns to step S6 (step C) in which the braking force against the rotation of the knee joint is made larger than in step S8 (step B).

  In step S6 (step C), increasing the braking force with respect to the rotation of the knee joint includes fixing the knee joint so that the knee joint does not bend or extend by applying the braking force with respect to the rotation of the knee joint, Applying a braking force against the rotation of the joint to bend or extend the knee joint at a lower speed than step S8 (step B).

  Generally, at the end of the stance, the braking force against the rotation of the knee joint is decreased to facilitate the operation of the knee joint. However, depending on the user, the value of the knee flexion moment M1 becomes excessively large at the end of the stance and the knee is broken. was there. However, in the present invention, even if an excessive knee bending moment occurs at the end of the stance, the knee joint becomes difficult to bend or extend by increasing the braking force against the rotation of the knee joint than in Step S8 (Step B). In addition, it is possible to prevent the knee from breaking.

  If the transition from the state not satisfying the equation (5) to the state satisfying the equation is not made, the braking force against the rotation of the knee joint is reduced (step S12). The case where the transition from the state not satisfying the formula (5) to the state satisfying does not mean that the gait is stable without excessively increasing the knee flexion moment M1 even at the end of the stance. . In this case, it is possible to promote the user to take a natural walking posture by reducing the braking force against the rotation of the knee joint so that the knee joint 11 can easily operate at the end of the stance.

  Although not shown in FIG. 3, after a predetermined delay time (third delay time) has elapsed since the transition from the state not satisfying the expression (5) to the state satisfied, the knee in step S6 is more than the knee in step S8. It is preferable to increase the braking force against the rotation of the joint. By providing the third delay time, it is possible to set the timing for adjusting the braking force against the rotation of the knee joint so as to match the gait of the user. The method of providing the third delay time in this way is particularly effective for a user whose knee position is not stable during walking. The third delay time can be set to 0.07 seconds to 0.2 seconds, for example.

  It is determined whether the elapsed time from the start of step S12 is within a third predetermined time (step S13). That is, it is determined whether or not the state where the braking force with respect to the rotation of the knee joint is reduced is within the third predetermined time. Thereby, the presence or absence of occurrence of abnormal walking can be estimated.

  The third predetermined time can be set to 1.0 to 2.0 seconds, for example. The third predetermined time may be set to a time corresponding to one walking cycle of the user.

  When the elapsed time from the start of step S12 is within the third predetermined time, the process returns to step S8 for reducing the braking force against the rotation of the knee joint. If the elapsed time from the start of step S12 is within the third predetermined time, it can be considered that the walking motion is continuing.

  When the duration of the state in step S12 exceeds the third predetermined time, the braking force for the rotation of the knee joint is made larger than that in step S12 (step S14). If the elapsed time from the start of step S12 exceeds the third predetermined time, it can be considered that the walking motion has ended.

In the second embodiment, ankle joint flexion moment M2 may be used instead of knee flexion moment M1. In that case, the following formula (2) is used instead of the formula (1) in step S4, the following formula (4) is used instead of the formula (3) in step S7, and the following formula is used instead of the formula (5) in step S11. Equation (6) may be used.
M2> C2 (2)
M2 <C4 (4)
M2> C6 (6)
However, C2 and C4 are constants, and C2 ≧ C4 ≧ 0 and C6 ≧ C4 ≧ 0. Further, C2> C4 ≧ 0 and C6> C4 ≧ 0 may be satisfied.

  In the knee joint control method of the present invention, the specific values of C5 to C6 are not particularly limited as long as the relationship of C5 ≧ C3 ≧ 0 and C6 ≧ C4 ≧ 0 is satisfied. , Sex, gait, disease progression, etc. can be set as appropriate. For example, C5 to C6 can be set to 0 N · m or more and 10 N · m or less.

  The value of the knee flexion moment M1 or the ankle plantar flexion moment M2 shows a peak at the initial stage of the stance and the final stage of the stance, but these values are higher in the initial stage of the stance than in the stance stage. Some people have an end-of-life value that is higher than the initial value. For this reason, the magnitude relationship between C1 and C5 and the magnitude relationship between C2 and C6 can be appropriately set according to the gait of the user. Specifically, the magnitude relationship between C1 and C5 may be C1> C5 or C1 <C5. Similarly, the magnitude relationship between C2 and C6 may be C2> C6 or C2 <C6.

(Embodiment 3)
In the third embodiment, an example in which the foot joint moment M2 is used for the control to increase the braking force with respect to the rotation of the knee joint 11 and the knee bending moment M1 is used for the control to reduce the braking force with respect to the rotation of the knee joint 11 will be described. FIG. 4 is a flowchart showing a knee joint control method according to Embodiment 3 of the present invention. In the description of FIG. 4, the description overlapping with the above description is omitted.

  When not walking, the braking force against the rotation of the knee joint 11 is increased (step S21).

  In order to determine whether the user has started walking, it is determined whether a knee flexion moment M1 has occurred (step S22). Specifically, it is preferable to determine whether M1> 0.

  In step S22, when the knee flexion moment M1 is not generated, the process returns to step S21 to increase the braking force against the rotation of the knee joint.

  In step S22, when the knee flexion moment M1 is generated, it is determined that the ankle joint flexion moment M2 is generated (step S23). Specifically, it is preferable to determine whether M2> 0.

  In step S23, when the ankle plantar flexion moment M2 is not generated, the process returns to step S21 to increase the braking force against the rotation of the knee joint.

  In step S23, when the ankle plantar flexion moment M2 is generated, it is determined that walking is started, and a walking loop is started (step S24).

After step S24, it is determined whether the state has been shifted from the state not satisfying the expression (2) to the state satisfied (step S25). Thereby, the start time of the initial stage of stance can be estimated.
M2> C2 (2)

  If the transition from the state not satisfying the expression (2) to the state satisfying the equation (2) is not made in step S25, the braking force against the rotation of the knee joint is increased (step S26). After step S26, the process returns to step S24 for starting the walking loop.

  In step S25, when the state is shifted from the state not satisfying the expression (2) to the state satisfied, the braking force against the rotation of the knee joint is increased (step S27 (step A)).

After step S27, it is determined whether the state has shifted from the state not satisfying the expression (3) to the state satisfied (step S28). Thereby, the start time of the middle stance can be estimated.
M1 <C3 (3)

  In step S28, when the state is shifted from the state not satisfying the expression (3) to the state satisfied, the braking force with respect to the rotation of the knee joint is made smaller than that in step S27 (step A) (step S29 (step B)).

  In step S28, when the state does not change from the state not satisfying the expression (3) to the state satisfying, the process returns to step S27 to increase the braking force against the rotation of the knee joint.

After step S29, it is determined whether or not the state is satisfied from the state not satisfying the expression (5) (step S30).
M1> C5 (5)

  In step S30, when the state is shifted from the state not satisfying the expression (5) to the state satisfied, the braking force against the rotation of the knee joint is set larger than that in step 29 (step B) (step S26 (step C)). As a result, it is possible to prevent the occurrence of knee bending caused by the knee flexion moment being increased at the end of stance.

  If the transition from the state not satisfying the equation (5) to the state satisfying the equation is not made, the braking force against the rotation of the knee joint is reduced (step S31). The case where the transition from the state not satisfying the formula (5) to the state satisfying does not mean that the gait is stable without excessively increasing the knee flexion moment M1 even at the end of the stance. . In this case, it is possible to promote the user to take a natural walking posture by reducing the braking force against the rotation of the knee joint so that the knee joint can easily operate at the end of the stance.

  After step S31, it is determined whether the elapsed time from the start of step S31 is within a third predetermined time (step S32). That is, it is determined whether or not the state where the braking force with respect to the rotation of the knee joint is reduced is within the third predetermined time. Thereby, the presence or absence of occurrence of abnormal walking can be estimated.

  If the elapsed time from the start of step S31 is within the third predetermined time, it is considered that the walking motion is continuing, and the process returns to step S29 for reducing the braking force against the rotation of the knee joint.

  If the elapsed time from the start of step S31 exceeds the third predetermined time, it is considered that the walking motion has ended, and the braking force for the rotation of the knee joint is made larger than that in step S31 (step S33).

  The knee joint control method shown in the third embodiment is suitable when the user can control the plantar flexor muscle (F2 in FIG. 1). This is because if the user can control the plantar flexor muscles, the plantar flexion moment M2 can be increased and the walking posture is relatively stable.

(Embodiment 4)
In the fourth embodiment, knee flexion moment M1 and ankle joint floor flexion moment M2 are used for controlling the knee joint. FIG. 5 is a flowchart showing a knee joint control method according to Embodiment 4 of the present invention. In the description of FIG. 5, the description overlapping with the above description is omitted.

  Steps S41 to S44 are the same as steps S21 to S24 of the third embodiment.

After step S44, it is determined whether the state has been shifted from the state not satisfying the expression (1) to the state satisfied (step S45).
M1> C1 (1)

  In step S45, when the state does not change from the state not satisfying the expression (1) to the state satisfied, the braking force against the rotation of the knee joint is increased (step S46).

In step S45, when a transition is made from a state not satisfying the expression (1) to a state satisfying the expression (2), it is determined whether or not the state is satisfied from the state not satisfying the expression (2) (step S47).
M2> C2 (2)

  If it is determined in step S47 that the condition (2) is not satisfied and the condition is not satisfied, the process returns to step S46 to increase the braking force against the rotation of the knee joint.

  In step S47, when the state is shifted from the state not satisfying the expression (2) to the state satisfied, the braking force against the rotation of the knee joint is increased (step S48 (step A)).

After step S48, it is determined whether the state has shifted from the state not satisfying the expression (3) to the state satisfied (step S49).
M1 <C3 (3)

  In step S49, when it does not shift from the state that does not satisfy the expression (3) to the state that satisfies, the process returns to step S48 in which the braking force against the rotation of the knee joint is increased.

In step S49, when the state is shifted from the state not satisfying the expression (3) to the state satisfied, it is determined whether the state is satisfied from the state not satisfying the expression (4) (step S50).
M2 <C4 (4)

  If the transition from the state not satisfying the expression (4) to the state satisfying the equation (4) is not made in step S50, the process returns to step S48 for increasing the braking force against the rotation of the knee joint.

  In step S50, when the state is shifted from the state not satisfying the expression (4) to the state satisfied, the braking force for the rotation of the knee joint is made smaller than in step S48 (step S51 (step B)).

After step S51, it is determined whether the state has been shifted from the state not satisfying the expression (5) to the state satisfied (step S52).
M1> C5 (5)

  In step S52, when the state is shifted from the state not satisfying the expression (5) to the state satisfied, the process returns to step S46 (step C) in which the braking force against the rotation of the knee joint is larger than that in step S51, and the walking loop is started again. To do.

If it is determined in step S52 that the state is not satisfied from the state not satisfying the expression (5), it is determined whether the state is satisfied from the state not satisfying the expression (6) (step S53).
M2> C6 (6)

  In step S53, when the state is shifted from the state not satisfying the expression (6) to the state satisfied, the process returns to step S46 (step C) for increasing the braking force against the rotation of the knee joint, and the walking loop is started again.

  In step S53, when the state does not change from the state not satisfying the expression (5) to the state satisfied, the braking force for the rotation of the knee joint is made smaller than that in step S48 (step A) (step S54).

  After step S53, it is determined whether the elapsed time from the start of step S54 is within a third predetermined time (step S55). That is, it is determined whether or not the state where the braking force with respect to the rotation of the knee joint is reduced is within the third predetermined time. Thereby, the presence or absence of occurrence of abnormal walking can be estimated.

  If the elapsed time from the start of step S54 is within the third predetermined time, it is considered that the walking motion is continuing, and the process returns to step S51 for reducing the braking force against the rotation of the knee joint.

  When the elapsed time from the start of step S54 exceeds the third predetermined time, it is considered that the walking motion has ended, and the braking force for the rotation of the knee joint is made larger than that in step S54 (step S56).

  As in the knee joint control method shown in the fourth embodiment, when transitioning from a state not satisfying the expression (1) to a state satisfying the expression (2) and shifting from a state not satisfying the expression (2) to a state satisfying the expression (2) In step S48 (step A), the braking force against the rotation of the knee joint is increased; the state in which the expression (3) is not satisfied is shifted to the state in which the expression (4) is not satisfied, and the condition in which the expression (4) is not satisfied. When the transition is made, the braking force for the rotation of the knee joint is made smaller in step S51 (step B) than in step A; the transition from the state not satisfying the expression (5) to the satisfying state is satisfied, and the expression (6) is satisfied. It is preferable to increase the braking force with respect to the rotation of the knee joint in step S46 (step C) than in step S48 (step A) when the state is shifted from the state not to be satisfied to the state satisfied. There. By using both the knee flexion moment M1 and the ankle plantar flexion moment M2 for the knee joint control, it is possible to improve the estimation accuracy of the walking cycle. Therefore, the timing accuracy for adjusting the braking force against the rotation of the knee joint is improved. Enhanced.

(Embodiment 5)
Acceleration may be used for controlling the knee joint. The acceleration is generated with the movement of the user. Here, the acceleration is the sum of the square of the X-axis direction component, the square of the Y-axis direction component, and the fourth power of the Z-axis direction (vertical direction) component (unit: g). Here, the X-axis direction and the Y-axis direction represent the traveling direction of the user, and 1 g is 9.8 m ² / s. Therefore, the acceleration A is expressed by the following formula 1, and the acceleration when there is no movement of the subject is zero. Since the acceleration A increases at the start of the initial stance, the start time of the initial stance can be estimated by observing the acceleration A.

That is, the acceleration A accompanying the user's movement is measured, and in step S5 (step A), the state transitions from the state not satisfying the expression (1) to the state satisfied, or the state satisfied from the state not satisfying the expression (2). It is preferable to increase the braking force with respect to the rotation of the knee joint as compared to step S8 (step B) when the process shifts to a state where the process shifts to a state where the expression (7) is not satisfied.
A> C7 (7)
However, C7 is a constant and C7> 0.

  Embodiment 5 is an example in which acceleration is further used for control to reduce the braking force against rotation of the knee joint in the knee joint control method according to Embodiment 2 shown in FIG. FIG. 6 is a flowchart showing a knee joint control method according to Embodiment 5 of the present invention. In the description of FIG. 6, the description overlapping with the above description is omitted.

  The knee joint control method shown in FIG. 6 is a method in which step S4 shown in FIG. 3 is replaced with steps S4-1 and S4-2.

  Steps S1 to S3 are the same as the knee joint control method according to the second embodiment shown in FIG.

  After step S3, it is determined whether the state has been shifted from the state not satisfying the expression (1) to the state satisfied (step S4-1).

  In step S4-1, when the transition from the state not satisfying the expression (1) to the state satisfying the equation (1) is not made, the process returns to step S6 for increasing the braking force against the rotation of the knee joint.

In step S4-1, it is determined whether the state has been shifted from the state not satisfying the equation (7) to the state satisfied when the state is satisfied from the state not satisfying the equation (1) (step S4-2).
A> C7 (7)

  In step S4-2, when the state is shifted from the state not satisfying the expression (7) to the state satisfied, the braking force against the rotation of the knee joint is increased (step S5 (step A)).

  In step S4-2, when the state does not change from the state not satisfying the expression (7) to the state satisfied, the process returns to step S6 for increasing the braking force with respect to the rotation of the knee joint.

  Steps S6 to S14 are the same as the knee joint control method of the second embodiment shown in FIG.

  In the fifth embodiment, the method of using the knee flexion moment M1 and the acceleration A to estimate the start time of the initial stance is shown as an example. However, the braking force against the rotation of the knee joint in the first and third to fourth embodiments is described. The acceleration A may be used for the control to reduce. Further, in the knee joint control method according to the first and second embodiments, the acceleration A may be further applied after using the ankle joint bottom bending moment M2 instead of the knee bending moment M1.

  Of course, it is possible to combine the ankle joint angle, the user's angular velocity, and the like in addition to the acceleration A so that the walking cycle can be accurately estimated and the timing accuracy for adjusting the braking force against the rotation of the knee joint can be improved. Further, by using in combination with a foot switch, an image analysis device, or the like that has been conventionally used for detecting the walking cycle, it is possible to perform more advanced control.

2. Lower limb orthosis The lower limb orthosis of this invention is demonstrated using FIGS. 7 to 8 are perspective views of the lower limb orthosis of the present invention, and FIG. 9 is a block diagram showing a configuration of the lower limb orthosis 50 of the present invention. In addition, in order to express clearly the position where a member is arrange | positioned, FIG. 7 shows the lower limb orthosis from which the measuring unit, the processing unit, and the driving unit are removed, and FIG. 8 shows the measuring unit and the processing unit described later. A lower limb orthosis with a drive attached is shown.

  As shown in FIG. 7, the lower limb orthosis 50 (50 </ b> A) includes a first component member 51 on the thigh side, a second component member 52 on the crus side, and a knee that holds the first component member 51 and the second component member 52. Part rotation member 53 (53A, 53B). In FIG. 7, the lower limb orthosis 50 is a right limb orthosis, and the knee rotating member 53 includes a knee rotating member 53 </ b> A located on the inner side (left foot side) and a knee rotating member 53 </ b> B located on the outer side.

  The first component member 51 on the thigh side is a member that supports the user's thigh, and includes, for example, a thigh cuff that is wound around the thigh and fixed. The first component member 51 may be provided with a half moon that wraps around the front or rear surface of the thigh as needed.

  The second component member 52 on the lower leg side is a member that supports the user's lower leg, and similarly to the first component member 51, for example, there is a lower leg cuff that is wound around the lower leg and fixed. The second component member 52 may be provided with a half moon that circulates the front or rear surface of the lower leg as needed.

  The material of the first component member 51 and the second component member 52 may be formed of, for example, a polymer material such as polyethylene, polypropylene, or polyvinyl chloride, a fabric such as a woven fabric, a knitted fabric, or a nonwoven fabric, or a combination thereof. . The first component member 51 and the second component member 52 are preferably formed from a polymer material. This is because it is hard to be deformed and has elasticity compared to the fabric.

  The knee rotation member 53 holds the first component member 51 and the second component member 52, and enables rotation of the knee joint, that is, bending and extension of the knee joint. In the lower limb orthosis 50 </ b> A, the knee rotation member 53 is connected to the first component member 51 via the upper column 54 and is connected to the second component 52 via the lower column 55. Although not shown, a knee pad or a band may be attached to the knee.

As shown in FIG. 8, the lower limb orthosis 50 is provided with a measuring unit 60, a processing unit 70, and a driving unit 80. The measuring unit 60 measures the knee bending moment M1 at the rotation center of the knee rotating member 53 (53B). The processing unit 70 determines that the knee flexion moment M1 satisfies the conditions of the expressions (1), (3), and (5). The drive unit 80 increases the braking force with respect to the rotation of the knee rotation member when shifting from the state not satisfying the expression (1) to the state satisfying, and shifts from the state not satisfying the expression (3) to the state satisfying. Sometimes the braking force against the rotation of the knee rotation member is made smaller than the braking force when shifting from the state not satisfying equation (1) to the state satisfying, and the state shifting from not satisfying equation (5) to the state satisfying When this is done, the braking force against the rotation of the knee rotation member is made larger than the braking force when the state changes from the state not satisfying the expression (3) to the state satisfied.
M1> C1 (1)
M1 <C3 (3)
M1> C5 (5)
However, C1, C3, and C5 are constants, and C1 ≧ C3 ≧ 0 and C5 ≧ C3 ≧ 0.

  Since the lower limb orthosis 50 of the present invention is provided with the measurement unit 60, the knee flexion moment M1 at the rotation center of the knee rotation member 53 can be measured. By determining whether the knee flexion moment M1 has shifted from the state not satisfying the expression (1) to the satisfied state in the measuring unit 60, the start time of the initial stance can be estimated. Further, by increasing the braking force against the rotation of the knee joint in the initial stage of the stance, it becomes difficult for the knee joint to bend or extend.

  By determining whether the knee flexion moment M1 has shifted from the state not satisfying the expression (3) to the state satisfied by the measurement unit 60, the start time of the middle stance can be estimated. By making the braking force against the rotation of the knee joint in the middle stance phase smaller than the braking force when the state shifts from the state not satisfying the expression (1) to the state satisfied, the knee joint can be easily bent or extended.

  By determining whether the knee flexion moment M1 has shifted from the state not satisfying the expression (5) to the state satisfied by the measurement unit 60, the start time of the stance end can be estimated. The braking force for the rotation of the knee joint at the end of the stance is made larger than the braking force when the state shifts from the state not satisfying the expression (3) to the state satisfied. As a result, even when the end of the stance is reached in an unstable state due to an excessive knee bending moment, the knee joint becomes difficult to bend or extend, so that it is possible to prevent the knee from being bent.

  Therefore, the lower limb orthosis 50 of the present invention can easily estimate the walking cycle by comparing the knee flexion moment M1 with the predetermined values C1, C3, and C5. Therefore, the knee joint can be easily controlled in real time.

  Hereinafter, a specific configuration of the lower limb orthosis 50 (50A) will be described. As shown in FIGS. 7 to 8, in the lower limb orthosis 50 </ b> A, a measurement unit 60 </ b> A, a processing unit 70, and a drive unit 80 are provided on the knee rotation member 53. As a method of providing the measurement unit 60A, the processing unit 70, and the driving unit 80 on the lower limb orthosis 50A, for example, a method of fixing by screwing, adhesion, welding, or the like, or a method of removably joining by a hook-and-loop fastener or the like can be used. .

  As shown in FIG. 9, the measurement unit 60A includes a knee flexion moment measurement unit 61 that measures the knee flexion moment M1. For the knee flexion moment measuring unit 61, the above-described load cell, electromyograph, or torque sensor can be used. The data of the knee flexion moment M1 measured by the measurement unit 60 is transmitted to the processing unit 70.

  The processing unit 70 determines whether the data transmitted from the measurement unit 60 has shifted from a state where the predetermined conditional expression is not satisfied to a state where it is satisfied. As illustrated in FIG. 9, the processing unit 70 receives the data transmitted from the measurement unit 60, the predetermined value storage unit 72 that stores the predetermined values C1, C3, and C5, and the transmission from the measurement unit 60A. The determination unit 73 is used to determine whether the conditions of the expressions (1), (3), and (5) are satisfied using the obtained data and a predetermined value. It is preferable that an input means (not shown) is provided in the predetermined value storage unit 72 so that the values of the predetermined values C1, C3, and C5 can be appropriately changed. Note that a known microprocessor can be used as the processing unit 70.

  The knee flexion moment M1 transmitted to the reception unit 71 and C1, C3, and C5 stored in the predetermined value storage unit 72 are transmitted to the determination unit 73, and the data transmitted to the reception unit 71 by the determination unit 73 Comparison with C1, C3, and C5 is performed, and it is determined whether the conditions of the expressions (1), (3), and (5) are satisfied. When the condition for transition from the state not satisfying the expression (1) to the state satisfied is satisfied in the determination unit 73, a signal for increasing the braking force against the rotation of the knee joint, for example, a fixation release signal for the knee joint is supplied to the drive unit 80. Send. Further, if the determination unit 73 of the processing unit 70 satisfies the condition for shifting from the state not satisfying the expression (3) to the state satisfying the expression (3), the braking force for the rotation of the knee joint is satisfied from the state not satisfying the expression (1). The signal which makes it smaller than the braking force when it transfers to the state to perform is transmitted to the drive part 80. FIG. Further, when the condition that the determination unit 73 of the processing unit 70 shifts from the state that does not satisfy the expression (5) to the state that satisfies the condition is satisfied, the braking force for the rotation of the knee joint is satisfied from the state that does not satisfy the expression (3). The signal which makes it larger than the braking force when it transfers to the state to perform is transmitted to the drive part 80. FIG.

  The driving unit 80 controls the magnitude of the braking force with respect to the rotation of the knee rotation member 53 based on the knee joint fixing signal or the fixing release signal transmitted from the determination unit 73 of the processing unit 70. Thereby, the motion of the knee joint can be appropriately controlled in accordance with the walking cycle. The drive unit 80 reduces the braking force against the rotation of the knee joint based on the fixation release signal from the processing unit 70 so that the knee joint can be moved freely. In addition, when the driving unit 80 receives a fixed signal from the processing unit 70, the braking force against the rotation of the knee joint is increased to prevent the user from bending the knee.

  Since the drive unit 80 applies a braking force to the rotation of the knee joint, the drive unit 80 is preferably provided on the knee rotation member 53. It is preferable that a hydraulic actuator or a pneumatic actuator is used for the drive unit 80 so that the knee joint control operation is performed smoothly.

  As shown in FIG. 7, the measurement unit 60, the processing unit 70, and the driving unit 80 are preferably provided so as to be detachable from the lower limb orthosis 50. Thereby, it becomes possible to use it as a lightweight lower limb orthosis from which the measuring unit 60, the processing unit 70, and the driving unit 80 are removed as necessary.

  As described above, since the lower limb orthosis 50A shown in FIG. 9 uses the knee flexion moment M1 for controlling the knee joint, for example, the control method according to the first embodiment of “1. Knee joint control method” described above is used. Can be implemented.

  A lower limb orthosis different from the above-described lower limb orthosis 50A will be described with reference to FIGS. 7 to 8 and FIGS. FIGS. 10-12 represents the block diagram which shows the other structural example of the leg brace of this invention.

As shown in FIGS. 7 to 8 and 10, the lower limb orthosis 50 (50 </ b> B) includes a third component member 56 on the ankle joint side, an ankle rotation member 57 that holds the second component member 52 and the third component member 56. The ankle bottom flexion moment M2 at the center of rotation of the ankle rotation member 57 is measured by the measurement unit 60; and the processing unit 70 determines that the conditions of the expressions (1) to (6) are satisfied. In the drive unit 80; when the transition from the state not satisfying the expression (1) to the state satisfying the expression (1), or the transition from the state not satisfying the expression (2) to the state satisfying the expression (2), The braking force against the rotation of the knee rotation member 53 when the power is increased; when shifting from the state not satisfying the expression (3) to the state satisfying, or when shifting from the state not satisfying the expression (4) to the state satisfying (1) Less than the braking force when shifting from the state not satisfying to the state satisfying or satisfying equation (2) to the state satisfying from equation (2); at least one of equations (5) and (6) When the condition (1) is satisfied, the braking force against the rotation of the knee rotation member 53 is shifted from a condition not satisfying the expression (3) to a satisfied condition, or from a condition not satisfying the expression (4) to a satisfied condition. It is preferable to make it larger than the braking force at the time of transition.
M2> C2 (2)
M2 <C4 (4)
M2> C6 (6)
However, C2, C4, and C6 are constants, and C2 ≧ C4 ≧ 0 and C6 ≧ C4 ≧ 0.
By using both the knee flexion moment M1 and the ankle plantar flexion moment M2 for controlling the knee joint, it is possible to improve the estimation accuracy of the walking cycle. Therefore, the timing accuracy for adjusting the braking force against the rotation of the knee joint is improved. Enhanced.

  The third component 56 on the ankle side functions as a foot placement member for placing the user's foot. The ankle portion rotation member 57 holds the third component member 56 and the second component member 52 and enables rotation of the ankle joint, that is, plantar flexion and dorsiflexion of the ankle joint. In the lower limb orthosis 50 (50 </ b> B), the ankle rotation member 57 is attached to the third component member 56 and is connected to the second component member 52 via the lower support column 55.

  As shown in FIG. 10, the lower limb orthosis 50 </ b> B preferably includes an ankle plantar flexion moment measuring unit 62 for measuring the ankle plantar flexion moment M <b> 2 by the measurement unit 60 (60 </ b> B). More preferably, 60B is provided. As with the knee flexion moment measuring unit 61, the above-described load cell, electromyograph, and torque sensor can be used for the ankle plantar flexion moment measuring unit 62.

  The ankle plantar flexion moment M2 measured by the measurement unit 60B is transmitted to the reception unit 71 of the processing unit 70 in the same manner as the knee flexion moment M1 of the lower limb orthosis 50A shown in FIG. At this time, predetermined values C1 to C6 are stored in the predetermined value storage unit 72. The determination unit 73 determines whether the conditions of the expressions (1) to (6) are satisfied. When the condition that the determination unit 73 shifts from a state that does not satisfy Expression (1) to a state that satisfies (2) or a state that does not satisfy Expression (2) is satisfied, the braking force against rotation of the knee joint is satisfied. Is transmitted to the drive unit 80, for example, a signal for releasing the fixation of the knee joint. Further, if the determination unit 73 of the processing unit 70 satisfies the condition that the condition (3) is not satisfied and the condition (3) is satisfied or the condition (4) is not satisfied and the condition is satisfied is satisfied. A signal for making the braking force for the rotation of the joint smaller than the braking force when the state changes from the state not satisfying the equation (1) to the state satisfied or when the state shifts from the state not satisfying the equation (2) to the satisfied state. It transmits to the drive part 80. Furthermore, when the determination unit 73 of the processing unit 70 satisfies the condition that the condition (5) is not satisfied and the condition (5) is satisfied or the condition (6) is not satisfied and the condition is satisfied is satisfied. A signal for making the braking force for the rotation of the joint larger than the braking force when the state changes from the state not satisfying the expression (3) to the state satisfied, or when the state shifts from the state not satisfying the expression (4) to the satisfied state. It transmits to the drive part 80.

  As described above, since the lower limb orthosis 50B shown in FIG. 10 can use the ankle plantar flexion moment M2 for controlling the knee joint in addition to the knee flexion moment M1, for example, as described above in “1. Knee joint”. The control method of Embodiments 3 to 5 of “Control method of” can be implemented.

  A lower limb orthosis 50 (50C) illustrated in FIG. 11 is an example in which an acceleration measurement unit 63 is provided in the measurement unit 60 (60A) of the lower limb orthosis illustrated in FIG. As a result, acceleration can be used for controlling the knee joint, and therefore, for example, the control method according to the fifth embodiment of “1. Knee joint control method” described above can be implemented.

  As the acceleration measuring unit 63, for example, a piezoresistive acceleration sensor, a piezoelectric acceleration sensor, a capacitive acceleration sensor, or the like can be used. In the lower limb orthosis 50C, the acceleration measuring unit 63 is provided on the knee rotating member 53, but the position where the acceleration measuring unit 63 is provided is not particularly limited, and the ankle rotating member 57, the first component member 51, and the second component. It may be provided on other members constituting the lower limb orthosis such as the component member 52.

  The acceleration A measured by the measurement unit 60A is transmitted to the reception unit 71 of the processing unit 70, similarly to the knee flexion moment M1. In this case, the predetermined value storage unit 72 stores the predetermined value C7. The determination unit 73 determines whether the state has shifted from the state not satisfying the expression (7) to the state satisfied.

  A lower limb orthosis 50 (50D) illustrated in FIG. 12 is an example in which the processing unit 70 is provided in an external terminal 90 capable of communicating with the measurement unit 60 and the drive unit 80. If the processing unit is provided in the external terminal 90, a doctor other than the user observes the data measured by the measurement unit 60, and C1 to C1 described on the right side of the equations (1) to (7). C7 can be changed remotely. As the external terminal 90, for example, a PC, a tablet terminal, a smartphone, or the like is used.

  In this specification, an example of controlling the knee joint using the lower limb orthosis has been shown. However, the method of controlling the magnitude of the braking force against the rotation of the joint using the joint moment is applied to other joints such as the hip joint and the elbow joint. Of course, the present invention can also be applied.

50, 50A, 50B, 50C, 50D: Lower limb orthosis 51: First component member 52: Second component member 53: Knee rotation member 56: Third component member 57: Ankle rotation member 60, 60A, 60B: Measurement unit 61: Knee flexion moment measurement unit 62: Ankle plantar flexion moment measurement unit 63: Acceleration measurement unit 70: Processing unit 71: Reception unit 72: Predetermined value storage unit 73: Determination unit 80: Drive unit 90: External terminal

Claims (10)

Measure at least one of the user's knee flexion moment M1 and ankle plantar flexion moment M2,
Step A for increasing the braking force against the rotation of the knee joint when transitioning from a state not satisfying the following expression (1) to a state satisfying, or when shifting from a state not satisfying the following expression (2) to a state satisfying: ,
M1> C1 (1)
M2> C2 (2)
When shifting from a state not satisfying the following equation (3) to a satisfying state, or when shifting from a state not satisfying the following equation (4) to a satisfying state, the braking force against the rotation of the knee joint is more than the step A. And a step B of reducing the knee joint control method.
M1 <C3 (3)
M2 <C4 (4)
However, C1 to C4 are constants, and C1 ≧ C3 ≧ 0 and C2 ≧ C4 ≧ 0. When shifting from a state not satisfying the following equation (5) to a satisfying state, or when shifting from a state not satisfying the following equation (6) to a satisfying state, the braking force against the rotation of the knee joint is more than the step B: The method for controlling a knee joint according to claim 1, comprising a step C of enlarging.
M1> C5 (5)
M2> C6 (6)
However, C5 to C6 are constants, and C5 ≧ C3 ≧ 0 and C6 ≧ C4 ≧ 0. In step A, the braking force against the rotation of the knee joint when the transition from the state not satisfying the equation (1) to the state satisfying the equation (1) and the transition from the state not satisfying the equation (2) to the state satisfied. Increase the
In step B, the braking force against the rotation of the knee joint when the state transitions from the state not satisfying the expression (3) to the state satisfied and from the state not satisfying the expression (4) to the state satisfied. Reduce the
In step C, the braking force against the rotation of the knee joint when the state transitions from the state not satisfying the expression (5) to the state satisfied and when the state shifts from the state not satisfying the expression (6) to the state satisfied. The method for controlling a knee joint according to claim 2, wherein the knee joint is increased.   In step C, after a predetermined delay time has elapsed since the transition from the state not satisfying the equation (5) to the state satisfied, or from the state not satisfying the condition of the equation (6) The method for controlling a knee joint according to claim 2 or 3, wherein a braking force with respect to rotation of the knee joint is larger than that in step B.   5. The braking force according to claim 1, wherein, in step B, after a predetermined time has elapsed since the braking force with respect to rotation of the knee joint is reduced, the braking force with respect to rotation of the knee joint is increased in step A. 6. The knee joint control method described. Measure the acceleration A accompanying the movement of the user,
In the step A, the state shifts from the state not satisfying the formula (1) to the state satisfied, or the state shifts from the state not satisfied the formula (2) to the state satisfied and does not satisfy the following formula (7) The knee joint control method according to any one of claims 1 to 5, wherein a braking force with respect to rotation of the knee joint is increased when a transition is made to a satisfied state.
A> C7 (7)
However, C7 is a constant and C7> 0.   In the step B, after a predetermined delay time has elapsed since the transition from the state not satisfying the expression (3) to the satisfied state, or the transition from the state not satisfying the expression (4) to the satisfied state, The knee joint control method according to any one of claims 1 to 6, wherein a braking force with respect to the rotation of the knee joint is made smaller than in step A. A lower limb orthosis comprising a first thigh-side component, a crus-side second component, and a knee component rotating member that holds the first component and the second component,
A measuring unit for measuring a knee bending moment M1 at the rotation center of the knee rotating member;
A processing unit for determining that the knee flexion moment M1 satisfies the following formula (1), the following formula (3), and the following formula (5);
Increasing the braking force against the rotation of the knee rotation member when shifting from a state not satisfying the following formula (1) to a state satisfying:
When the transition from the state not satisfying the following equation (3) to the state satisfying is satisfied, the braking force against the rotation of the knee rotating member is determined from the braking force when the state is satisfied from the state not satisfying the following equation (1) And make it smaller
When the transition from the state not satisfying the following equation (5) to the state satisfying is satisfied, the braking force against the rotation of the knee rotation member is determined from the braking force when the state is satisfied from the state not satisfying the following equation (3). And a lower limb orthosis characterized by being provided with a drive unit that also enlarges.
M1> C1 (1)
M1 <C3 (3)
M1> C5 (5)
However, C1, C3, and C5 are constants, and C1 ≧ C3 ≧ 0 and C5 ≧ C3 ≧ 0. A third component on the ankle side, an ankle rotation member that holds the second component and the third component,
An ankle plantar flexion moment M2 at the rotation center of the ankle portion rotation member is measured in the measurement unit,
In the processing unit, it is determined that the expression (1), the expression (3), the expression (5), the following expression (2), the following expression (4), and the following expression (6) are satisfied.
When the drive unit shifts from a state that does not satisfy the equation (1) to a state that satisfies the equation (1) or a state that does not satisfy the following equation (2), the rotation of the knee rotation member Increase the braking force against
When shifting from a state not satisfying the expression (3) to a state satisfying, or when shifting from a state not satisfying the following expression (4) to a state satisfying, the braking force against the rotation of the knee rotating member is Smaller than the braking force when shifting from a state not satisfying equation (1) to a state satisfying, or when shifting from a state not satisfying equation (2) to a state satisfying,
When shifting from a state not satisfying the expression (5) to a state satisfying, or from a state not satisfying the following expression (6) to a state satisfying, the braking force against the rotation of the knee rotating member is The lower limb orthosis according to claim 8, wherein the lower extremity orthosis is greater than the braking force when the state transitions from a state not satisfying the expression (3) to a state satisfied, or when the state shifts from the state not satisfying the expression (4) to a state satisfied. .
M2> C2 (2)
M2 <C4 (4)
M2> C6 (6)
However, C2, C4, and C6 are constants, and C2 ≧ C4 ≧ 0 and C6 ≧ C4 ≧ 0. The lower limb orthosis of Claim 8 or 9 with which the said process part is provided in the external terminal which can communicate with the said measurement part and the said drive part.