JP2012095953A - Walking support device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a walking support device which can cope with a situation in which the load pattern of a walking user changes originating from the user carrying a baggage or holding on a handrail.SOLUTION: The walking support device 100 includes a leg device 10 and a controller 12. The leg device 10 includes a thigh link 20 and a crus link 30, which are mounted to the leg, a motor 26 and a load sensor 32. The motor 26 swings the crus link 30. The load sensor 32 detects the load applied to the leg sole. The controller 12 memorizes a target pattern describing a change with time of a knee angle corresponding to an idling leg action while walking, and controls the motor 26 so that the crus link 30 follows the target pattern. The controller 12 starts follow-up control to the target pattern when the detected load falls below a second threshold value after exceeding a first threshold value. Furthermore, when the peak value of the load change gets out of a prescribed load range, the controller 12 reports this fact to the user.

Description

  The present invention relates to a walking support device that is attached to a user's leg and supports the user's walking motion.

  2. Description of the Related Art In recent years, a walking support device that actively induces a user's leg movement by an actuator has been proposed. Such a walking support device has a structure in which a thigh link and a lower thigh link that are attached to the user's thigh and lower thigh are swingably connected, and an actuator swings the lower thigh link.

  In general, actuator control includes torque control and angle control. As the former example, there is one that controls the actuator so that the output torque of the actuator matches a predetermined target torque pattern. As another example of the former in the walking support device, there is one that controls the actuator so as to output a torque corresponding to the joint angle of the leg or a torque corresponding to the floor reaction force applied to the user's foot. As an example of angle control in the walking support device, there is one in which the actuator is controlled so that the swing angle of the lower leg link follows a target pattern describing a change with time of a predetermined target swing angle. An example of a torque-controlled walking support device is disclosed in Patent Document 1.

JP 2002-301124 A

  As one application destination of the walking support device, it has been proposed to be used for walking training for non-healthy persons who cannot move the knee joint freely. For a user wearing a walking support device, the switch operation for instructing start and stop of actuator control is troublesome. As one of the ideas for reducing the load of the switch operation, it is conceivable to configure the walking support device so as to start the follow-up control to the target pattern with a change in the load applied to the sole as a trigger. When trying to swing a leg forward in walking motion, the load is removed from the leg. The walking support device is configured to start follow-up control to a target pattern corresponding to the swing leg motion when it is detected that the load has been removed from the leg. For example, when the walking support device is configured to start the follow-up control when the load falls below a threshold value, the user applies a load to the other leg, and the one leg (the walking support device is attached). If the weight is moved laterally so that the load is removed from the leg), the walking support device can be started to support the free leg movement.

  The above walking support device is considered to work well in an environment such as rehabilitation that allows walking while keeping the body in a specific state. However, when it is assumed that the above-described walking support device is used in a normal social life, the walking support device is required to operate appropriately even in a situation where the user has a luggage or is held by a handrail. In such a situation, in a walking support device that starts support using a load change as a trigger, the load pattern during the walking motion changes when the user holds a load or is held by a handrail, and at an inappropriate timing. There is a possibility that a trigger is generated or a trigger that should be generated is not generated. The present specification provides a walking support device that can cope with a situation in which a load pattern during walking changes due to a user holding a load or being held by a handrail.

  The technology disclosed in this specification sets a predetermined load range in addition to a trigger for starting support of walking motion (hereinafter referred to as a follow-up control start trigger), and the load applied to the sole deviates from the range. An algorithm for determining that the user's state has changed is incorporated into the walking support device. By skillfully constructing the algorithm that generates the trigger for starting the tracking control and the above judgment algorithm, and combining them, the load pattern in the walking motion changes due to the user holding the luggage or being held by the handrail A walking support device that can appropriately cope with the situation is realized.

  One aspect of the walking support device disclosed in this specification includes a leg brace and a controller. The leg brace includes a thigh link and a thigh link that are attached to each of the user's thigh and thigh, an actuator, and a load sensor. The lower leg link is swingably connected to the thigh link at a position coaxial with the rotation axis of the knee joint when the user wears a leg brace. The actuator swings the crus link with respect to the thigh link. The load sensor detects a load applied to the sole of the leg wearing the leg brace. The controller stores a target pattern describing a temporal change in the lower leg swing angle corresponding to the swing leg movement during walking, and controls the actuator so that the lower leg link follows the target pattern. The target pattern is predetermined. Then, the controller starts the follow-up control of the actuator to the target pattern with a trigger that the load detected by the load sensor falls below the second load threshold after exceeding the first load threshold. Furthermore, when the controller detects that the peak value of the load change is out of the load range including the first load threshold value, the controller notifies the user. The “notification” may be a lamp, a buzzer, or a device that reproduces previously recorded audio data. Further, the first load threshold, the second load threshold, and the load range are determined in advance and stored in the controller.

  The features of the walking support device described above are that, firstly, the place to be supported is the swing of the lower leg (that is, the angle of the knee joint), and a target pattern corresponding to the free leg movement of the leg is adopted. An example of the target pattern will be described in the embodiment, but the end of the target pattern indicates the posture of the lower leg (the angle formed by the thigh and the lower leg) at the timing when the swing leg movement ends, that is, the timing when the swing leg lands. The posture corresponds to a state where the knee is almost extended. While the supporting leg is a standing leg, the leg brace holds the end value of the target pattern. The target pattern is only the period corresponding to the free leg movement, and during the standing leg, the angle of the lower leg link is kept constant so that a trigger is generated each time the leg becomes a free leg and the movement of the walking support device is started. It can be synchronized with the user's walking motion.

  Secondly, the walking support device is characterized in that the load applied to the sole (the load detected by the load sensor) exceeds the first load threshold and then falls below the second load threshold to trigger the target pattern of the actuator. Is to start the following control. The magnitudes of the first load threshold and the second load threshold are determined in advance based on the weight of the user and the characteristics of walking motion. In one example, the first load threshold is set to a size that is at least half the weight of the user, and the second load threshold is set to a small value close to zero (at least a value smaller than the first load threshold). The situation in which the detected load exceeds the first load threshold is a situation in which more weight is applied to the leg (affected leg) wearing the leg brace than the other leg. A typical such situation is when the affected leg is a standing leg and the other leg is a free leg. The situation in which the detected load falls below the second load threshold is a situation in which almost no weight is applied to the affected leg. A typical example of such a situation is immediately before the affected leg takes off in the walking motion. That is, the condition of the first load threshold and the second load threshold described above corresponds to detecting immediately before the affected leg becomes a free leg after the affected leg becomes a single leg stand. By adding the condition of the first load threshold, it is possible to prevent the leg brace from starting the operation when the weight is lost from the affected leg for some reason other than the walking operation.

  Third, the walking support device is characterized by notifying the user when the peak value of the load change deviates from a predetermined load range including the first load threshold. The load range is determined in advance based on the weight of the user and the characteristics of the walking motion. The peak value in the load pattern during walking is substantially constant during normal walking motion. It is presumed that the situation where the load peak value is excessive is when the user has a load. It is estimated that the situation where the load peak value is too small is when the user is using a handrail. In either case, since the target pattern deviates from the situation assumed (the situation where the user walks without carrying a baggage and without using a handrail), the movement of the leg brace may cause a mismatch with the user's walking movement. is there. The user's attention is alerted by notifying the user of such a situation. Note that the load peak value exceeding the predetermined load range can be detected when the measured load exceeds the upper limit of the load range without detecting the load peak value. Further, when the load peak value falls below the predetermined load range, the first load threshold condition is not satisfied, so that the leg brace does not operate even if the user's leg becomes a free leg. In such a case, the user can understand the reason why the leg brace does not operate by receiving notification from the controller.

  Note that “when the peak value of the load change deviates from a predetermined load range including the first load threshold value is notified to the user” as a technical idea, the peak value is a load even once. This means that notification is made when the value is out of the range, but in order to eliminate the influence of noise or the like, notification may be made when a situation in which the peak value is out of the load range is detected over several steps. .

  If the load peak value exceeds the predetermined load range, the user is likely to have a load. In such a case, the target pattern that is set assuming a normal walking state may not be appropriate. Therefore, when the load peak value exceeds the predetermined load range, it is preferable that the controller does not start control of the actuator even if the load falls below the second load threshold.

  The present specification also provides a walking support device according to another aspect related to the second feature of the walking support device. The leg brace of the walking support device may have the structure described above. The controller stores a predetermined target pattern describing a temporal change in the crus swing angle corresponding to the swinging leg movement during walking, and controls the actuator so that the crus link follows the target pattern. This controller starts the follow-up control of the actuator to the target pattern with a trigger that the load detected by the load sensor falls below the first load threshold after exceeding a predetermined first load threshold. This walking support device focuses only on the second feature described above, and is a modification of the second feature. In the case of this walking support device, the first load threshold is set to a smaller value rather than at least half of the user's weight. In the case of this walking support device, “when the load detected by the load sensor has fallen below the first load threshold after exceeding the predetermined first load threshold” means “after the affected leg has landed” Corresponds to “Before Takeoff”.

  In the above walking support device, “the load detected by the load sensor exceeds the load threshold” means a timing at which the detected load changes from a value smaller than the load threshold to a value larger than the load threshold. It should be noted that “the load detected by the load sensor falls below the load threshold” means a timing at which the detected load changes from a value larger than the load threshold to a value smaller than the load threshold.

  The technology disclosed in the present specification provides a walking support device corresponding to a situation in which a load pattern in a walking motion changes due to a user holding a load or being held by a handrail.

It is a perspective view of a walking assistance device. It is a block diagram of a walk assistance device. It is a figure explaining the change of the knee angle in walking. It is a figure explaining the meaning of the code | symbol in FIG. It is a flowchart figure of the trigger process of tracking control start. It is a flowchart figure of a load pattern monitoring process.

  A schematic diagram of the walking support device 100 of the first embodiment is shown in FIG. The walking support device 100 is mainly configured by a leg brace 10 attached to one leg of the user U and a controller 12 that controls the leg brace 10. In this example, user U is assumed to be a patient whose left leg is healthy but whose right leg cannot move freely. Since the left leg is healthy, the leg brace 10 is attached only to the right leg.

  Before describing the walking support device 100, the coordinate system will be described. As shown in FIG. 1, the front of the user U is taken as the X axis, the side is taken as the Y axis, and the vertically upper side is taken as the Z axis. In the technical field of robots, in general, an axis (X axis) extending in the front-rear direction of the robot (human body) is called a roll axis, and an axis (Y axis) extending to the side of the robot (human body) is called a pitch axis. An axis extending vertically upward (Z axis) is referred to as a yaw axis.

  The structure of the leg orthosis 10 will be described. The leg brace 10 includes a thigh link 20, a crus link 30, and a foot link 40. The thigh link 20, the lower leg link 30, and the foot link 40 are attached to the affected leg UA (here, the right leg) of the user U who needs assistance. Specifically, the thigh link 20 is attached to the thigh UB, the lower leg link 30 is attached to the lower leg UD, and the foot link 40 is attached to the foot UE.

  The thigh link 20 and the crus link 30 are connected on both sides of the user's knee joint UC. Specifically, the thigh link 20 and the crus link 30 are rotatably connected by a pair of knee joints 25 positioned coaxially with the user's knee joint. A motor 26 and an angle sensor 27 are built in the outer knee joint 25. The motor 26 swings the crus link 30 around the knee pitch axis. Hereinafter, an angle formed by the thigh link 20 and the crus link 30 is referred to as a knee angle. The angle measured by the angle sensor 27 is the swing angle of the crus link 30 with respect to the thigh link 20, but the angle also corresponds to the knee angle formed by the user's U thigh UB and the crus UD.

  The lower leg link 30 and the foot link 40 are connected on both sides of the user's ankle joint. Specifically, the lower leg link 30 and the foot link 40 are rotatably connected by a pair of ankle joints 34 that are positioned coaxially with the pitch axis of the user's ankle joint. The ankle joint 34 does not include an actuator, and the foot link 40 swings passively according to the swing of the user U's foot. A load sensor 32 is disposed on the sole of the foot link 40 and measures a ground load when the right leg of the user U is grounded.

  The controller 12 incorporates a small computer and a battery, supplies power to each part of the leg brace 10 via the cable 16, and controls the operation of each part of the leg brace 10. The controller 12 is an example, but is attached to the trunk (waist) of the user U. The controller 12 is fixed to the trunk of the user U by the wearing belt 14. Note that the position where the controller 12 is mounted is not particularly limited, and may be configured to be mounted on the back of the user U, for example. The controller 12 controls the motor 26 based on the sensor data of the angle sensor 27 and the load sensor 32.

  FIG. 2 shows a block diagram of the walking support device 100. The controller 12 includes a CPU 12a, a speaker 12b, and a storage device 12c that stores target pattern data. Although not shown, the storage device 12c also stores various programs executed by the CPU 12a. The CPU 12a (controller 12) acquires knee angle data from the angle sensor 27, and acquires load data applied to the right leg sole from the load sensor 32. The CPU 12a (controller 12) determines the timing for starting the follow-up control based on the data. The follow-up control will be described later. The CPU 12a (controller 12) starts follow-up control for causing the swing angle of the lower leg link 30 to follow the target pattern at the determined timing.

  With reference to FIG. 3 and FIG. 4, the change with time of the knee angle (lower leg swing angle) during walking and the target pattern will be described. The upper side of FIG. 3 is a graph showing the change over time of the knee angle Ak of the right leg. The lower side of FIG. 3 is a graph showing a change with time of the load W applied to the sole of the right leg. The vertical axis of the upper graph in FIG. 3 indicates the knee angle, and the horizontal axis is the time axis. FIG. 4 is a diagram for explaining the definition of parameters used in FIG. In FIG. 4, the solid line represents the right leg and the broken line represents the left leg. The solid line above the hip joint represents the trunk. The same applies to the line drawings shown in FIGS. 3A to 3F. A straight line L1 indicates a straight line connecting the rotation center around the pitch axis of the hip joint and the rotation center of the knee joint. In other words, the straight line L1 is a straight line along the longitudinal direction of the thigh. The knee angle Ak is defined as an angle from the straight line L1 toward the lower leg. The knee angle Ak = 0 when the knee is fully extended. When the knee bends at a right angle, the knee angle Ak = + 90 degrees.

  Returning to FIG. 3, the walking motion will be described. As is clear from the figure, the temporal change in the knee angle in one walking cycle has a profile in which a small mountain (peak) and a large mountain (peak) are continuous. In general, a small mountain corresponds to the stance phase, and a large mountain corresponds to the swing phase. The load W shows a positive value only in the stance period, and the load W is zero in the free leg period.

  The walking motion will be described for each timing shown in the figure. The line drawings from (a) to (f) in FIG. 3 show the posture of the leg at each timing from timing Ta to timing Tf. Timing Ta indicates the timing at which the right leg lands. The timing Tb is a timing at which the knee angle Ak becomes the largest during the standing period of the right leg. The timing Tb also corresponds to the timing at which the knee angle of the left leg, which is a free leg, becomes the largest. The timing Tc corresponds to the timing at which the heel of the right leg starts to float after the left leg has landed and the lower leg starts to swing backward. Timing Td indicates the timing at which the right leg takes off. Timing Te indicates the timing at which the knee angle Ak becomes the largest in the right leg swing phase period. The leg mode shown in (e) and the leg mode shown in (b) are the same except that the left and right legs are interchanged. Timing Tf is the timing at which the right leg contacts the ground, and is the same as timing Ta. That is, the period from the timing Ta to the timing Tf corresponds to one cycle of walking, and a new walking cycle starts from the timing Tf.

  The period from timing Tc to Td is a period in which the right leg foot is grounded but the heel is lifted and the entire right leg swings forward, and is called a pressing period. During the pressing period, there is virtually no load on the right leg. Therefore, it is up to the definition whether this pressing period is included in the swing phase or in the stance phase. In this specification, the pressing period is included in the swing period because it does not substantially support weight. In other words, in this embodiment, the period from timing Ta to Tc corresponds to the stance phase of the right leg, and the period from timing Tc to timing Tf corresponds to the swing period of the right leg.

  The load W applied to the right leg is zero until the timing Ta, which is the landing timing, and increases rapidly after the timing Ta. The change in the load W takes the peak value Wp during the stance period and then decreases and becomes zero at the takeoff timing Td.

  The graph of FIG. 3 shows an ideal change over time of the knee angle in walking of a healthy person. The controller 12 stores, as a target pattern, the pattern of the knee angle Ak in the swing phase in the knee angle Ak graph on the upper side of FIG. Then, the controller 12 controls the motor 26 based on the sensor data of the angle sensor 27 so that the swing angle of the crus link 30 follows the target pattern. This control is referred to as follow-up control. Note that after reaching the end of the target pattern, the controller 12 controls the motor 26 so as to maintain the target value at the end of the target pattern (that is, knee angle = 0).

  The controller 12 starts the follow-up control with a change in the load W satisfying a predetermined condition as a trigger. FIG. 5 shows a flowchart of a process for determining a trigger for starting the follow-up control (follow-up control trigger process). The controller 12 always monitors the load W. The controller 12 monitors whether or not the load W measured by the load sensor 32 has exceeded the first load threshold Wt1 (S4). When it is detected that the load W has exceeded the first load threshold Wt1 (S4: YES), the controller 12 starts a timer (S6), and then whether the load W has fallen below a predetermined second load threshold Wt2 Whether or not is monitored (S8). The controller 12 monitors the output (load W) of the load sensor 32 until the elapsed time Ts from the timer start exceeds a predetermined time threshold Tst (S12: NO). When the time threshold Tst is exceeded (S12: YES), the controller 12 resets the timer (S14) and returns to the load monitoring in step S4 again. The processes in steps S12 and S14 correspond to a reset process when a trigger does not occur even after a predetermined time has elapsed (when an affirmative determination does not occur in the process of step S8).

  When the controller 12 detects that the load W has fallen below the second load threshold Wt2 before the elapsed time Ts exceeds the time threshold Tst (S8: YES), the controller 12 starts follow-up control (S10). In other words, when step S8 makes an affirmative determination, follow-up control to the target pattern starting from timing Tc in FIG. 3 is started. As illustrated in the lower graph of FIG. 3, the first load threshold Wt1 is set to a value larger than the second load threshold Wt2. Conversely, the second load threshold Wt2 is set to a relatively small value. As shown by the upper and lower graphs in FIG. 3, ideally, the timing when the load W falls below the second load threshold Wt2 preferably coincides with the timing Tc at which the user raises the heel. Since the load change pattern during walking is substantially constant, the timing at which the load W falls below the second load threshold Wt2 generally coincides with the timing at which the user raises the right leg heel. The first load threshold Wt1 is set to a value that is at least larger than half of the user's weight (but smaller than the user's weight). Naturally, both the first load threshold Wt1 and the second load threshold Wt2 are positive values.

  The advantages of the tracking control trigger process will be described. With this process, the user can instruct the walking support apparatus 100 to start tracking control without troublesome switch operation. This is not the only advantage of the process of FIG. In the walking motion, the user's weight moves sequentially to the left and right legs. First, the user swings forward the left leg, which is a healthy leg, as a free leg. Meanwhile, the right leg becomes a standing leg, the load increases, and exceeds the first load threshold Wt1. As the left leg lands and the weight moves from the right leg to the left leg, the load on the right leg decreases and falls below the second load threshold Wt2. At that timing, the walking support device 100 starts tracking control to the free leg target pattern. In other words, the walking support device 100 obtains a trigger for starting free leg assistance for the right leg in the natural motion of the user's healthy leg (left leg).

  The controller 12 also executes the load pattern monitoring process of FIG. 6 in parallel with the tracking control trigger process of FIG. The load pattern monitoring process is a process for detecting that the load change pattern has changed, for example, when the user holds a load or grabs a handrail. This load pattern monitoring process will be described next.

  The controller 12 stores a load upper limit value Wa and a load lower limit value Wb. Hereinafter, the load upper limit Wa is simply referred to as the upper limit Wa, and the load lower limit Wb is simply referred to as the lower limit Wb. As shown in the lower graph of FIG. 3, the upper limit value Wa is set to a value larger than the first load threshold value Wt1, and the lower limit value Wb is set to a value smaller than the first load threshold value Wt1. In other words, the controller 12 stores a load range (Wa> Wt1> Wb) including the first load threshold Wt1. The controller 12 monitors whether or not the load W detected by the load sensor 32 exceeds the upper limit value Wa (S23). When the load W exceeds the upper limit value Wa (S23: YES), the controller 12 outputs a message to that effect (that is, the load W is excessively large) (S28). This message is stored in advance in the controller 12 as synthesized voice data, and is output from the speaker 12b included in the controller 12 in the process of step S27. Then, the controller 12 stops the trigger process shown in FIG. 5 (S29).

  On the other hand, when the load W is smaller than the upper limit value Wa (S23: NO), the controller 12 calculates the change speed dW of the load W (S24). The change speed dW is obtained by dividing the value obtained by subtracting the load W measured last time from the load W measured this time by the time interval between the previous measurement timing and the current measurement timing. When the change speed dW of the load W takes a positive value, it indicates that the load W increases, and when the change speed dW takes a negative value, it indicates that the load W decreases. The controller 12 also stores the change speed dW calculated last time. When the previous change speed dW takes a positive value (S25: YES) and the current change speed dW takes a negative value (S26: YES), the controller 12 moves the process to step S27. The case where the previous change speed dW takes a positive value and the current change speed dW takes a negative value corresponds to the timing at which the change speed changes from increase to decrease, that is, the timing at which the load W takes a peak value. When the load W reaches the peak value, the controller 12 monitors whether or not the load W (load peak value Wp) at that time is below the lower limit value Wb (S27). When the load peak value Wp is below the lower limit value Wb (S27: YES), the controller 12 outputs a message (S28) and stops the trigger process (S29).

  The advantages of the load pattern monitoring process will be described. When the load W exceeds the upper limit value Wa (step S23: YES), in other words, the load peak value Wp exceeds the upper limit value Wa. Therefore, the load pattern monitoring process is a process for monitoring whether or not the load peak value Wp is out of the range including the first load threshold value Wt1 (Wa> Wp> Wb). When the load peak value Wp is out of the load range (Wa> Wp> Wb), the controller 12 outputs a message to that effect and stops the trigger process. That is, when the load peak value Wp is out of the load range (Wa> Wp> Wb), the controller 12 does not start the follow-up control even when the load W falls below the second load threshold Wt2.

  The case where the peak value Wp of the load deviates from the load range (Wa> Wp> Wb) corresponds to the case where the user has a load or is gripped by a handrail. In such a situation, there is a high possibility that the predetermined target pattern is not appropriate, and thus the walking assistance device 100 cancels the next tracking control. The user who has received the message stops walking and sets the first and second load thresholds when he / she intends to maintain the same load situation (load situation with luggage or using handrails). cure.

  Next, a walking support apparatus according to the second embodiment will be described. This walking support device is different in control algorithm from the walking support device of the first embodiment. Since the hardware configuration of the walking support device of the second embodiment is the same as that of the first embodiment, description thereof is omitted. The walking support apparatus according to the second embodiment also stores a knee angle target pattern, and executes the follow-up control trigger process of FIG. However, in the walking assistance device of the second embodiment, the first load threshold Wt1 = the second load threshold Wt2 is set in the flowchart of the tracking control trigger process of FIG. The second load threshold value Wt2 is set to a value (positive value) smaller than half of the user's weight, as in the case of the first embodiment.

  The follow-up control trigger process executed by the controller of the second embodiment can be summarized as follows. The controller starts the follow-up control with a trigger that the load W detected by the load sensor 32 falls below the first load threshold value after exceeding a predetermined positive first load threshold value Wt1. In the case of this walking support device, the case where “the load detected by the load sensor exceeds the predetermined positive first load threshold and then falls below the first load threshold” is detected as “the affected leg is Corresponds to “Before landing and just before taking off”. This walking support device has an advantage that the algorithm is simplified compared to the walking support device of the first embodiment, and the movement of the leg brace is easy to understand.

  Specific examples of the present invention have been described in detail above, but these are merely examples and do not limit the scope of the claims. The technology described in the claims includes various modifications and changes of the specific examples illustrated above. The technical elements described in this specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. In addition, the technology exemplified in this specification or the drawings can achieve a plurality of objects at the same time, and has technical usefulness by achieving one of the objects.

10: Leg orthosis 12: Controller 20: Thigh link 25: Knee joint 26: Motor 27: Angle sensor 30: Lower leg link 32: Load sensor 100: Walking support device

Claims (3)

A thigh link attached to the user's thigh;
A thigh link that is swingably connected to the thigh link and is attached to the user's thigh,
An actuator that swings the lower leg;
A load sensor for detecting the load applied to the sole of the leg wearing the thigh link and the lower leg link;
A controller that controls the actuator so that the crus link follows a target pattern that describes the change over time of the crus swing angle corresponding to the swing motion of the free leg during walking,
The controller starts following control of the actuator to the target pattern triggered by the fact that the load detected by the load sensor exceeds a predetermined first load threshold and then falls below a predetermined second load threshold. When the peak value of the load change deviates from a predetermined load range including the first load threshold, the user is notified that the peak value deviates from the load range.   2. The walking support according to claim 1, wherein when it is detected that the peak value exceeds the load range, the controller does not start control of the actuator even if the peak value falls below a second load threshold thereafter. apparatus. A thigh link attached to the user's thigh;
A thigh link that is swingably connected to the thigh link and is attached to the user's thigh,
An actuator that swings the lower leg;
A load sensor for detecting the load applied to the sole of the leg wearing the thigh link and the lower leg link;
A controller that controls the actuator so that the lower leg link follows the target pattern describing the temporal change in the lower leg swing angle corresponding to the swinging leg movement during walking, and the load detected by the load sensor is predetermined. A controller that starts the follow-up control to the target pattern of the actuator triggered by the fact that the first load threshold value is exceeded after exceeding one load threshold value;
A walking support device comprising:

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