JP2013208291A - Walking assistance device and walking assistance program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable walking by an ideal shift of the center of gravity, by reducing a wearer's feeling of discomfort from the walking.SOLUTION: A state during walking is determined from a body parameter, a joint angle and a floor reaction force and the like, and control is performed by means of a battery so that ideal right and left positions of the center of gravity can be set. More specifically, a person's position of the center of gravity is calculated by acquiring a walking state of a pedestrian wearing a walking assistance device; the calculated position of the center of gravity is compared with the ideal right and left positions of the center of gravity in the walking state; and a difference between the positions of the center of gravity is corrected by sliding the battery in a horizontal direction. A rightward/leftward shift of the center of gravity, which is required for the walking, is partially performed instead by the battery. Thus, the positions of the center of gravity in a state in which the walking assistance device is worn become the ideal right and left positions of the center of gravity; the width of the person's own rightward and leftward winging becomes small; and kinetic energy for the person's walking can be reduced. In addition, since a wearer walks on the basis of the ideal shift of the center of gravity even when walking in his/her peculiar way of walking, he/she can perform the effortless walking without a feeling of discomfort.

Description

  The present invention relates to a walking support device and a walking support program, and, for example, relates to a device that supports walking of a wearer.

2. Description of the Related Art In recent years, the development of bipedal robots has been remarkable, and there are robots that can not only walk statically but also can walk dynamically and bipedal robots that can run.
Note that the static walk is a walk in which the projected point of the center of gravity on the road surface is located on either the left or right sole, and the dynamic walk is a walk in which the projected point deviates from the left or right sole.

  When biped walking, it is important how to adjust the position of the center of gravity, and as one of the techniques for that purpose, as in “Robot and center of gravity position control method of robot” in Patent Document 1, There is a technique that makes it difficult to fall by using a heavy object attached to the body (for example, an arm or a battery) as a balancer, and also enables a movement similar to that of a person to walk.

In addition, there is a walking robot that is applied as a walking assistance device in wearable mobility that assists the wearer's walking, such as the “walking assist device” of Patent Document 2. The walking assist device operates in synchronization with the wearer's walking and assists the wearer's muscle strength.
In the case of a walking support device, the position of the center of gravity can be adjusted by the wearer appropriately displacing body parts such as arms and waists.

By the way, when a person walks, he / she walks while moving the center of gravity position in the left / right direction. However, the current situation is that the ideal center of gravity is not necessarily moved.
On the other hand, the conventional walking assistance device merely assists the force necessary for raising and lowering the foot. For this reason, if the pedestrian wearing the walking support device tries to move the center of gravity forcibly, the walking is far from his / her own heel, and the user feels uncomfortable.
On the other hand, if the ideal center-of-gravity movement is not performed with the walking assistance device attached, the burden on the pedestrian increases. Although it is possible to increase the assist rate in order to reduce this burden, there is a problem that the efficiency of the apparatus is deteriorated.
The technology of Patent Document 1 was developed for a biped walking robot, and was developed for the purpose of controlling to prevent falling, and on the premise that the locus of the center of gravity is controlled so as to achieve ideal walking. Therefore, there is a problem that it cannot be applied to human natural walking.

JP 2001-129775 A JP 2011-142958 A

  An object of the present invention is to enable walking by the ideal center-of-gravity movement as much as possible while reducing the discomfort of the wearer with respect to walking.

(1) In the first aspect of the present invention, the heavy object moving means for moving the heavy object constituting the walking support device in the left-right direction, and the gravity center position of the walking support target excluding the heavy object as the human body gravity center position. The human body gravity center position acquisition means to acquire, the reference center of gravity position acquisition means to acquire the reference position of the center of gravity corresponding to the acquired human body gravity center position, and the entire walking support target person including the heavy object equipped with the walking support device And a heavy object movement control means for controlling movement of the heavy object by the heavy object movement means so that the position of the center of gravity is closer to the reference position of the center of gravity than the position of the center of gravity of the human body. Providing the device.
(2) In the invention described in claim 2, the heavy article movement control means controls the heavy article to move outward from a reference position of the acquired center of gravity. A walking support device according to 1 is provided.
(3) In the invention described in claim 3, the heavy object moving means moves, in the left-right direction, at least a battery that supplies power as the heavy object. Providing the device.
(4) The invention according to claim 4 is a walking support program for a walking support device provided with a heavy load moving means for moving a heavy load constituting the walking support device in the left-right direction, excluding the heavy load. Equipped with a human body centroid position acquisition function that acquires the centroid position of the walking support target person as the human body centroid position, a reference centroid position acquisition function that acquires the reference position of the centroid corresponding to the acquired human centroid position, and a walking support device The heavy object movement control function for controlling the movement of the heavy object by the heavy object moving means so that the overall gravity center position of the walking support target person including the heavy object is closer to the reference position of the gravity center than the human body gravity center position. And a walking support program that realizes the above with a computer.

  According to the present invention, the weight object is moved so that the overall gravity center position of the walking support target person including the heavy object wearing the walking assistance device is closer to the reference position of the center of gravity than the human body gravity center position. Can walk efficiently without fatigue due to ideal movement of the center of gravity without feeling uncomfortable with walking.

It is the figure which showed the mounting state of the mounting type robot. It is the figure which showed the system configuration | structure of the mounting | wearing type robot. It is a figure for demonstrating a walk cycle. It is a figure for demonstrating an ideal gravity center locus | trajectory. It is explanatory drawing of the operation | movement correct | amended so that the gravity center position of the whole apparatus may correspond with an ideal gravity center by the movement of a battery. It is a flowchart for demonstrating the procedure of a gravity center correction process.

(1) Outline of Embodiment The ideal left-right center of gravity position in each phase of walking is determined, and the continuity is the center-of-gravity locus.
In this embodiment, the state during walking is determined from various parameters (body parameters, joint angles, floor reaction force, etc.) (each phase from the initial grounding to the end of the free leg in walking), and the ideal walking state is determined. Control is performed using a structural member (a heavy object such as a battery) of the walking support device located near the center of gravity of the person so that the center of gravity is located on the left and right.
That is, the walking state of the pedestrian wearing the walking support device is acquired to calculate the position of the center of gravity of the person, the calculated center of gravity position is compared with the ideal left and right center of gravity position in the walking state, and the difference is walked. Correction is performed by sliding the structure of the support device (battery or the like) in the left-right direction.
By replacing part of the left and right center of gravity movement necessary for walking with the structure of the walking support device, the center of gravity position with the walking support device attached becomes the ideal left and right center of gravity position, and the person's own left and right swing width is It becomes small and can reduce the kinetic energy for a person to walk. In addition, for the wearer, even if walking with his / her own heel, it is an ideal walking with a center of gravity movement, and therefore, a comfortable walking with no sense of incongruity can be performed.

(2) Details of Embodiment Hereinafter, the walking support apparatus according to the present embodiment will be described using the wearable robot 1 shown in FIG. 1 as an example.
FIG. 1 is a diagram showing a wearing state of the wearing robot 1.
The wearable robot 1 is worn on the waist and lower limbs of the wearer to assist (assist) the wearer's walking.
The wearable robot 1 includes a control device 50, a waist attachment portion 21, an upper thigh attachment portion 22, a lower leg attachment portion 23, a foot attachment portion 24, an upper thigh connection member 26, a lower thigh connection member 27, a control device 2, and a toe reaction force sensor. 10, heel reaction force sensor 11, toe posture sensor 12, heel posture sensor 13, waist posture sensor 14, upper leg posture sensor 15, lower leg posture sensor 16, hip joint assist actuator 17, knee joint assist actuator 18, ankle joint assist actuator 19 Etc. The components other than the waist mounting part 21, the control device 50, and the waist posture sensor 14 are provided on the left and right feet, and the respective detection values are output.
However, the toe reaction force sensor 10 and the heel reaction force sensor 11 may be provided with a toe grounding sensor and a heel grounding sensor instead of both sensors in the embodiment in which the detection of the reaction force is unnecessary. .

The waist mounting portion 21 is attached around the waist of the wearer and fixes the wearable robot 1.
The waist posture sensor 14 is attached to the waist attachment portion 21 and detects the posture of the waist (roll angle, yaw angle, pitch angle) with a gyroscope or the like. Also, by differentiating these angles, the angular velocity and angular acceleration of the waist can be obtained.

The control device 50 is attached to the waist mounting portion 21 and controls the operation of the wearable robot 1.
The control device 50 includes a battery 21 (to be described later) as a power source for driving each actuator such as the hip joint assist actuator 17 and each sensor unit, and a heavy object that moves (slides) the battery 21 in the left-right direction. A slide actuator 20 (described later) is provided.
The battery 21 functions as a heavy object disposed in the vicinity of the center of gravity of the human body constituting the wearable robot (walking support device) 1 (which is a structure).
In the present embodiment, the case where the battery 21 is used as a heavy object disposed in the vicinity of the human body will be described. However, in addition, the entire control device 50 including the battery 21 or the control device 50 excluding the battery 21 is used. It may be. Further, a dedicated balancer may be separately arranged as a heavy object.

The hip joint assist actuator 17 is provided at the same height as the hip joint of the wearer, and drives the upper thigh coupling member 26 in the front-rear direction with respect to the waist mounting portion 21.
The hip joint assist actuator 17 may be driven not only in the front-rear direction with respect to the waist attachment portion 21 but also in the lateral direction and the oblique direction. In this case, the hip joint assist actuator 17 can be configured by combining an actuator that drives in the front-rear direction and an actuator that drives in the lateral direction. By combining the operations of the longitudinal actuator and the lateral actuator, the hip joint can be driven three-dimensionally in the longitudinal direction, the lateral direction, and the oblique direction. Alternatively, the hip joint assist actuator 17 may be a single triaxial actuator.

The upper thigh coupling member 26 is a rigid columnar member provided outside the upper thigh of the wearer, and is fixed to the upper thigh of the wearer by the upper thigh mounting portion 22. The upper thigh connecting member 26 is driven by the hip joint assist actuator 17 to support the movement of the upper thigh.
The outer side of the upper thigh mounting part 22 is fixed to the inner side of the upper thigh coupling member 26, and the inner side is fixed to the upper leg of the wearer.
The upper leg posture sensor 15 detects the upper leg posture (roll angle, yaw angle, pitch angle). In addition, by differentiating these angles, the angular velocity and acceleration of the upper thigh can be obtained.

The knee joint assist actuator 18 is provided at the same height as the knee joint of the wearer, and moves the lower leg connection member 27 in the front-rear direction with respect to the upper leg connection member 26 to move the lower leg of the wearer. Support.
The crus connecting member 27 is a columnar member having rigidity provided outside the crus of the wearer, and is fixed to the crus of the wearer by the crus attachment 23. The lower leg connecting member 27 is driven by the knee joint assist actuator 18 to support the movement of the lower leg.

The outer side of the lower leg mounting portion 23 is fixed to the inner side of the lower leg connecting member 27, and the inner side is fixed to the lower leg of the wearer.
The lower leg posture sensor 16 detects the lower leg posture (roll angle, yaw angle, pitch angle). Also, by differentiating these angles, the angular velocity and angular acceleration of the lower leg can be obtained.

The ankle joint assist actuator 19 is provided at the same height as the wearer's ankle joint, and drives the toe of the foot mounting portion 24 in the direction of moving up and down with respect to the crus coupling member 27. The ankle joint assist actuator 19 may also be driven in a lateral direction or an oblique direction in the same manner as the hip joint assist actuator 17.
The foot mounting portion 24 is fixed to the foot portion (instep and sole) of the wearer. Generally, the joint at the base of the toe is bent during walking, but the foot mounting portion 24 is also configured so that the base of the toe is bent according to the toes.

  The toe posture sensor 12 and the heel posture sensor 13 are respectively installed at the front end and the rear end of the foot mounting portion 24 and detect the toe and heel postures (roll angle, yaw angle, pitch angle), respectively. Further, by differentiating these angles, the angular velocity and angular acceleration of the toes and the heel can be obtained.

The toe reaction force sensor 10 is installed in front of the sole portion of the foot mounting portion 24 and detects the ground contact of the toe and the reaction force from the walking surface.
The heel reaction force sensor 11 is installed on the rear side of the sole of the foot mounting portion 24 and detects the ground contact of the heel and also detects the reaction force from the walking surface.
The wearable robot 1 configured as described above supports the walking of the wearer by driving the hip joint assist actuator 17, the knee joint assist actuator 18, and the ankle joint assist actuator 19.

FIG. 2 is a diagram showing a system configuration of the wearable robot 1.
The control device 50 is an electronic control unit having a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a clock as means for measuring time, a storage unit, various interfaces, and the like (not shown). Yes, each part of the wearable robot 1 is electronically controlled.

  The control device 50 is also configured by executing various programs such as a walking support program stored in the storage unit by the CPU, and includes a body parameter input unit 51, a sensor information acquisition unit 52, various parameter calculation units 53, and a human body. The center of gravity calculation unit 54, the ideal center of gravity calculation unit 55, the center of gravity locus comparison unit 56, the walking assist force determination unit 57, and the center of gravity correction determination unit 58 are provided.

The body parameter input unit 51 receives input of physical parameters such as the height and weight of the wearer from, for example, a keyboard. These parameters are used to calculate the position of the wearer's human body center, ideal center of gravity (reference position of the center of gravity), and left-right direction locus (left-right direction locus).
The center of gravity of the human body is the position of the center of gravity of the walking support target person excluding the movable object (battery 21) by the heavy load slide actuator 20 from the wearer wearing the wearable robot 1, and the ideal center of gravity is the wearing position. It is the center of gravity of the body when the person is walking ideally.

  The sensor information acquisition unit 52 acquires a detection value from each of the toe reaction force sensor 10 to the crus posture sensor 16. The detection value of each sensor acquired by the sensor information acquisition unit 52 is used for determination of a walking state (each phase of walking to be described later) and calculation of the position of the human body gravity center, ideal gravity center, and the like.

  The various parameter calculation unit 53 calculates the angle, position, angular velocity, joint moment, and the like of each joint from the detection values acquired by the sensor information acquisition unit 52. These calculated values are used for the determination of the walking state (each phase of walking described later) and the calculation of the position of the human body gravity center and the ideal center of gravity.

  The human body center-of-gravity calculation unit 54 calculates the current position of the center of gravity of the human body from the data input by the body parameter input unit 51, the sensor value acquired by the sensor information acquisition unit 52, and the calculated values of various parameter calculation units 53, and The left and right trajectory of the human body center of gravity is calculated from the temporal transition.

The ideal center-of-gravity calculation unit 55 determines the current walking phase (described later) from the data input by the body parameter input unit 51, the sensor value acquired by the sensor information acquisition unit 52, and the calculated values of the various parameter calculation unit 53. Then, the position of the ideal center of gravity of the wearer in the phase is calculated, and further, the trajectory of the ideal center of gravity in the left-right direction is calculated based on the temporal transition.
The center-of-gravity locus comparison unit 56 compares the left-right direction locus of the human body center of gravity calculated by the human body center-of-gravity calculation unit 54 with the left-right direction locus of the ideal center of gravity calculated by the ideal center-of-gravity calculation unit 55, and calculates the difference between the two.

  The walking assist force determining unit 57 determines the assist force to be output to the hip joint assist actuator 17, the knee joint assist actuator 18, and the ankle joint assist actuator 19 disposed on the left and right feet, and drives these assist actuators accordingly. . That is, the walking assist force determination unit 57 requires a necessary assist force (for example, a value obtained by multiplying a necessary joint moment by a predetermined ratio) according to the joint moment necessary for the movement of each joint calculated by the various parameter calculation unit 53. And the assist actuator is driven.

The center-of-gravity correction determination unit 58 drives the heavy object slide actuator 20 so that the difference calculated by the center-of-gravity locus comparison unit 56 approaches 0 (that is, the lateral locus of the human body center of gravity approaches the lateral locus of the ideal center of gravity). To move the battery 21 left and right.
The movement of the battery 21 moves on the ideal center of gravity side with respect to the human body center of gravity position and on the outside of the ideal center of gravity position. As a result, the overall center of gravity position (the center of gravity when the wearable robot 1 is mounted), which is the sum of the center of gravity of the human body and the battery 21 that is a movable heavy object, moves to the position of the ideal center of gravity. However, if it is on the ideal center of gravity side, even if it is inside the ideal center of gravity position, it is possible to obtain a certain effect that it is possible to walk efficiently compared to the case where the battery 21 is fixed.

The heavy load slide actuator 20 is an actuator for moving the battery 21 used as a heavy load to the left and right, and includes a ball screw or the like.
In general, the amount of movement of the ideal center of gravity is in the range of 4 cm to 10 cm in width.
Therefore, the movable range of the battery 21 by the heavy load slide actuator 20 is formed in a range larger than the movement width of the ideal center of gravity because the battery needs to be moved outside the ideal center of gravity.
For example, although it changes with the weight of a heavy article (battery 21), it is formed so that it can move in the range of a total of 20 cm by 10 cm in the left-right direction from the left-right center of the body. However, within this movable range, when the ideal center of gravity is located on the outermost side, if the overall center of gravity position cannot be corrected to the position of the ideal center of gravity 32, the weight of the heavy object is increased or / and movable. The range is expanded to the range of the maximum width of the wearable robot 1.
The increase in the weight of the heavy object is not limited to the battery 21, but a structure other than the battery 21, for example, the entire control device including the battery 21 is a movable object as a heavy object.

FIG. 3 is a diagram for explaining the walking cycle.
The walking cycle is a cycle in which one leg makes one cycle during walking. Here, the observation limb is assumed to be the right foot, and the opposite foot is assumed to be the left foot. The same applies to the case where the observation limb is the left foot and the opposite foot is the right foot.
The walking cycle is roughly classified into the stance phase and the swing phase. The stance phase is a period in which the right foot (observation limb) is in contact with the ground, and the swing phase is a period in which the right foot is away from the ground.

Furthermore, the stance phase is classified into an initial ground contact a (initial contact), a load response phase b (loading response), a mid-stance phase c (mid stance), and a stance end phase d (terminal stance).
On the other hand, the free leg period is classified into the previous free leg period e (pressing), the free leg initial stage f (initial swing), the free leg middle period g (mid swing), and the free leg end period h (terminal swing).

The initial grounding a and the load response period b are periods in which the body load is inherited when the other leg shifts from the stance phase to the swing phase.
The initial grounding a is a moment when the right foot comes into contact with the ground after swinging in the swing phase. Each phase of the walking cycle is determined by comprehensively determining values from the sensor information acquisition unit 52 and various parameter calculation units 53. The initial ground contact a is mainly determined by the output of the left side reaction force sensor 11. This can be done by detecting grounding.

The load response period b is a period from the initial ground contact a to the moment when the right foot leaves the ground. During this period, the weight moves quickly to the left.
The end of the weighted response period can be performed mainly by detecting the moment when the right foot is separated from the ground by the toe reaction force sensor 10 of the right foot.

The middle stance phase c and the last stance phase d are both periods in which the body is supported by a single leg (here, the left leg).
The middle stance c is a period from the moment when the left foot is separated from the ground to the moment when the heel of the right foot is separated from the ground. During this period, the body is moved forward with the right foot as a fulcrum, and the trunk is secured.
The end of the middle stance c is performed mainly by detecting the moment when the right footpad is separated by the right footpad reaction force sensor 11.

The stance end d is a period from the moment when the right foot heel leaves the ground to the initial grounding a of the left foot. During this period, the body is carried before the supporting foot.
The end of the stance end d is performed mainly by detecting the ground contact by the left side reaction force sensor 11.

On the other hand, the free leg period e to the free leg end period h of the swing leg period is a period in which the swing leg is moved forward (swings in space).
The front swing leg period e is a period from the initial ground contact a of the left foot to the moment when the toe of the right foot leaves the ground. This period is a period for preparing for the free leg initial stage f.
The end of the front swing leg period e is mainly performed by detecting that the toes are separated from the ground by the toe reaction force sensor 10 of the right foot.

The free leg initial f is a period from the moment when the toe of the left foot is separated from the ground until the lower leg of both feet intersects. During this period, take your right foot away from the ground and carry it forward.
The end of the free leg initial stage f is performed by calculating the state of the right foot and the state of the left foot based on the output of each sensor and determining the intersection of the lower leg.

The free leg middle period g is a period from the intersection of the lower leg of both feet to the moment when the lower leg of the right foot is perpendicular to the ground. During this period, the right foot is further moved and the clearance between the toes and the ground is secured.
The end of the free leg middle period g is performed by calculating the state of the right foot based on the output of each sensor and determining that the lower leg of the right foot is perpendicular to the ground.

The free leg end period h is a period from when the lower leg of both feet is perpendicular to the ground until the heel of the right foot contacts the ground. During this period, the forward movement of the right foot is terminated and preparations are made for standing on the right foot.
The end of the free leg end period h is performed mainly by detecting the ground contact by the reaction force sensor 11 of the right foot.
As described above, one walking cycle of the right foot is configured. The same applies to one walking cycle of the left foot.

Each figure of FIG. 4 is a figure for demonstrating the movement of the left-right direction of the ideal gravity center 32 in a walk.
Each figure has shown the place which looked at the pedestrian who is performing the ideal walk from the front. Since it is an ideal walk, the position of the center of gravity of the human body matches the position of the ideal center of gravity 32.
4 (a) to 4 (h) correspond to each phase from the initial ground contact a to the free leg end h in one walking cycle of the right foot.
As shown in FIG. 4, it can be seen that the ideal center of gravity 32 existing near the waist of a person has moved an equal distance from side to side with respect to the virtual reference line A during one walking cycle in walking.

The position of the ideal center of gravity 32 in each phase of walking changes as follows in the order of FIGS.
However, FIG. 4 shows a view of the pedestrian from the front and the position of the ideal center of gravity 32, and the direction of movement of the ideal center of gravity 32 will be described as a direction viewed from the viewpoint of the person facing the pedestrian. . Therefore, when the movement of the ideal gravity center 32 is described as the right direction, it is a leftward movement for the pedestrian.
The same applies to FIG. 5 described later.

As shown in FIGS. 4A to 4H, the position of the ideal center of gravity 32 with respect to the reference line A in each phase of walking is slightly to the right of the reference line at the initial ground contact a, but in the load response period b, the reference line Move to the left side of A.
Then, when changing to the middle stance phase c (upper left), the ideal center of gravity 32 moves further to the left side of the reference line A, and at the final stance phase d, the leftmost end is folded back toward the reference line A direction.
In the front swing leg period e, it moves from the left to the vicinity of the reference line A, and in the free swing initial stage f, it passes through the reference line A and moves to the right side.
Further, at the free leg middle stage g, the ideal center of gravity 32 continues to move to the right from the reference line, and at the free leg end stage h, the rightmost end is folded back toward the reference line A direction.

FIG. 5 is a diagram for describing an operation for correcting the center of gravity of the entire apparatus to match the ideal center of gravity 32 by the movement of the battery 21 in the present embodiment.
FIG. 5A shows a state in which the human body gravity center 33 is moved to the ideal gravity center 32 position at the end of the free leg without moving the battery 21.
In this state, the position of the ideal center of gravity 32 represented by the line P is the state moved most rightward from the reference line A, and the position of the center of gravity of the human body (the center of gravity of the wearable robot 1 and the person excluding the battery 21) is also the line P. It may feel that it is necessary to move to the outside considerably for a pedestrian who has a disability or a habit of walking. For such a pedestrian, it is tired because it moves to the center of gravity 33 forcibly. It may be easy to feel or you may feel uncomfortable.

On the other hand, FIG. 5B shows the position of the center of gravity at the end of the free leg when the heavy battery 21 is moved by the heavy load slide actuator 20 in the present embodiment.
The ideal center of gravity 32 in FIG. 5B represents a state where the ideal center of gravity 32 has moved from the reference line A at the end of the free leg to the same position as in FIG.
As shown in this figure, the difference between the human body center of gravity 33 located on the line Q and the position ideal center of gravity 32 on the line P is calculated and corresponds to the difference as indicated by the arrow m by the heavy object slide actuator 20. The battery 21 is moved outside the line P by the amount of movement.

Note that the position of the battery 21 after movement is determined and controlled by the gravity center correction determination unit 58.
That is, the center-of-gravity correction determination unit 58 calculates the human body center-of-gravity calculation unit 54 based on the data input by the body parameter input unit 51, the sensor values acquired by the sensor information acquisition unit 52, and the calculated values of various parameter calculation units 53. The movement amount (movement target position) of the battery 21 is obtained from the current position of the human body centroid 33 and the difference between the human centroid 33 and the ideal centroid 32 calculated by the centroid locus comparison unit 56 corresponding to the current position.
Specifically, the position (on the line P) of the ideal weight 32 corresponding to the current position (on the line Q) of the human body center of gravity 33 is obtained, and the position of the battery 21 for the overall center of gravity located on the line P is corrected for the center of gravity. The heavy load slide actuator 20 is driven so that the battery 21 moves to the position calculated by the determination unit 58 and determined.

As a result, the total center of gravity of the human body center of gravity 33 and the battery 21 is moved on the line P in the same manner as the ideal center of gravity 32, thereby realizing ideal walking and reducing energy loss and fatigue of the wearer. Can do.
Further, as can be understood from the fact that the movement amount of the human body center of gravity 33 is closer to the reference line A than the ideal center of gravity 32, the wearer needs to move less in the lateral direction with respect to the reference line A. It is possible to walk comfortably without a sense of incongruity because there is no movement and the habit of walking is not changed.

  Even during the process of correcting the center of gravity due to the movement of the battery 21, the calculation of the joint moment according to the walking state by the various parameter calculation unit 53, and the walking assist force determination unit 57 according to the calculated joint moment, Walking assistance (assist) is performed by the joint assist actuators 17 to 19.

FIG. 6 is a flowchart for explaining the procedure of the center-of-gravity correction process performed by the wearable robot 1.
The following processing is performed by the CPU included in the control device 50 according to a predetermined program.
First, the control device 50 acquires various data (step 5). Specifically, in addition to data such as height and weight input by the body parameter input unit 51, sensor values such as floor reaction force acquired by the sensor information acquisition unit 52, joints calculated by various parameter calculation units 53 Acquire various data such as angle, joint angular velocity, and joint moment.
Next, the control device 50 performs walking determination using these data (step 10). This determination is to determine whether or not the wearer is walking.

When it is not walking based on the walking determination result (step 15; N), the control device 50 determines whether or not to stop the assist operation (step 110).
This determination is made, for example, to determine whether the wearer has temporarily stopped walking or has turned off the assist function. For example, when the wearer manually turns off the assist function, the assist operation is stopped. Judge.
When the operation is stopped (step 110; Y), the control device 50 ends the process, and when the operation is not stopped (step 110; N), the control device 50 returns to step 5.

On the other hand, when walking (step 15; Y), the control device 50 determines which phase of the walking cycle is currently based on the data acquired in step 5 (step 20).
As a result of the determination, when the phase is the initial ground a (step 25, Y), the control device 50 performs the correction process including the following steps 30 to 40.

  First, the control device 50 acquires the current position of the human body center of gravity by the human body center of gravity calculation unit 54, further acquires the position of the ideal center of gravity 32 at the initial ground contact a by the ideal center of gravity 32 calculation unit 55, and the center of gravity locus comparison unit 56. The center of gravity position is compared by (step 30).

As a result of comparison, when the position of the human body centroid 33 (position on the line Q in FIG. 5B) and the position of the ideal centroid 32 (position on the line P in FIG. 5B) are different (step 35; N) The control device 50 drives the heavy load slide actuator 20 by the gravity center correction determination unit 58 to correct the deviation (step 40), and ends the correction (step 45). That is, the control device 50 determines a target position of the battery 21 corresponding to the current position of the human body center of gravity 33, and drives the battery 21 to the target position with the heavy load slide actuator 20.
On the other hand, if there is no deviation as a result of the comparison (step 35; Y), the control device 50 ends the correction (step 45). The control device 50 returns to Step 5 after completing the correction.
The determination of whether or not there is a shift may be made by determining that there is a shift when the difference between the two is equal to or greater than a predetermined threshold, and determining that there is no shift when the difference is less than the predetermined threshold.

On the other hand, when the walking cycle determination is not the initial ground contact a (step 25; N), the control device 50 determines whether or not the phase is the load response period b (step 50).
When the phase is the load response period b (step 50; Y), the control device 50 performs a correction process based on a comparison between the position of the ideal center of gravity 32 and the current position of the human body center of gravity in the load response period b (step 55). Then, the correction is completed (step 45), and the process returns to step 5.
Since this correction process (step 55) is the same as the correction process of steps 30 to 40 for the initial grounding a, description thereof is omitted (the same applies hereinafter).
When the phase is not in the load response period b (step 50; N), the control device 50 determines whether or not the phase is in the mid-stance phase c (step 60).

When the phase is the middle stance c (step 60; Y), the control device 50 performs a correction process based on the comparison between the position of the ideal center of gravity 32 and the current position of the human body center of gravity in the middle stance c (step 65). (Step 45), and the process returns to step 5.
When the phase is not the middle stance phase c (step 60; N), the control device 50 determines whether or not the phase is the last stance phase d (step 70).

When the phase is the stance end d (step 70; Y), the control device 50 performs a correction process based on the comparison between the position of the ideal center of gravity 32 and the current position of the human body center of gravity at the end of stance d (step 75). (Step 45), and the process returns to step 5.
When the phase is not the stance end d (step 70; N), the control device 50 determines whether or not the phase is the free leg initial f (step 80).

When the phase is the free leg initial f (step 80; Y), the control device 50 performs a correction process based on the comparison between the position of the ideal center of gravity 32 and the current position of the human body center of gravity at the initial stage of the free leg f (step 85). The correction is completed (step 45), and the process returns to step 5.
When the phase is not the free leg initial f (step 80; N), the control device 50 determines whether or not the phase is the free leg middle period g (step 90).

  When the phase is the swing leg middle period g (step 90; Y), the control device 50 performs a correction process based on the comparison of the position of the ideal center of gravity 32 and the current position of the human body center of gravity in the swing leg middle period g (step 95). The correction is completed (step 45), and the process returns to step 5.

  When the phase is not the swinging leg middle stage g (step 90; N), the control device 50 determines that the phase is the swinging leg end stage h. Then, the control device 50 performs a correction process based on a comparison between the position of the ideal gravity center 32 and the current position of the human body gravity center at the free leg end h (step 105), ends the correction (step 45), and returns to step 5. .

  As described above, the wearable robot 1 is efficient for the wearer by moving the heavy battery 21 so that the trajectory of the center of gravity of the entire device on which the apparatus is mounted becomes the trajectory of the ideal center of gravity 32. You can walk without a sense of incongruity.

As mentioned above, although the embodiment at the time of applying the walking support device of the present invention to the wearing type robot 1 was described, the present invention is not limited to the described embodiment, and various kinds are included in the range described in each claim. Deformation can be performed.
For example, in the embodiment described above, an example in which the position of the ideal centroid changes in the left-right direction around the reference line A has been described as an example, but the ideal centroid is centered around the reference line B that is orthogonal to the reference line A and parallel to the horizontal plane. It is also possible to determine whether or not the battery 21 moves in the front-rear direction, and to correct the front-rear direction in addition to the left-right direction by moving the battery 21.
In this case, in order to perform the correction in the front-rear direction, the battery 21 includes a heavy load vertical actuator that moves the battery 21 in the vertical direction.
As a result, the battery 21 moves on a plane parallel to the body surface of the wearer.

In the described embodiment, since the human body centroid is closer to the reference axis A than the ideal centroid as the positional relationship between the human centroid and the ideal centroid that can occur normally, the heavy load slide actuator 20 is always outside the ideal centroid. The case of moving to is described.
On the other hand, when the amount of deviation between the human body center of gravity and the ideal center of gravity is negative, that is, when the human body center of gravity 33 is outside the ideal center of gravity 32 with respect to the reference line A, the heavy object (battery 21) is You may make it move to the central-axis A side rather than the position of the ideal gravity center 32. FIG.

Further, in the described embodiment, one walking cycle is divided into eight steps from the initial grounding a to the stance cycle h as described in FIGS. 3 and 4, but more finely divided (for example, each phase in the previous period, 16 phases divided into the latter half, the first half, the middle, the late 24, etc.).
In this case, the ideal center-of-gravity position for each subdivided phase may be determined in advance. As a result, the difference between the human center of gravity and the ideal center of gravity can be calculated easily and quickly.

  In the embodiment described above, the place where the center of gravity of a person (wearing state) excluding the battery from the state in which the wearable robot 1 is worn is acquired as the human body center of gravity has been described. The position may be the center of gravity of the human body. This is because, when the battery 21 that moves to the left and right is removed, the mounting robot 1 is configured to have a weight that is symmetrical to the wearer.

According to the embodiment described above, the following configuration can be obtained.
The wearable robot 1 sequentially acquires the position (reference position of the center of gravity) of the ideal center of gravity 32 corresponding to each walking cycle from the initial grounding a to the free leg end h by the ideal center of gravity 32 calculation unit 55. Reference position trajectory acquisition means for acquiring a trajectory of the reference position of the center of gravity of the person corresponding to the walking cycle is provided.
In addition, the wearable robot 1 sequentially samples the wearer's human center of gravity (center of gravity position) corresponding to each walking cycle from the initial grounding a to the free leg end h by the human body center of gravity calculation unit 54. It is provided with a center-of-gravity position locus acquisition means for acquiring the locus of the center of gravity of the person corresponding to the walking cycle.
In addition, when the difference (deviation) between the ideal center of gravity 32 and the human body center of gravity is greater than or equal to a predetermined threshold, the wearable robot 1 drives each actuator so as to be less than the threshold to correct the walking posture of the wearer. And a posture control means for controlling the posture of the walking support target so that a deviation between the acquired locus of the reference position and the acquired locus of the center of gravity is equal to or less than a predetermined amount.

  In addition, the wearable robot 1 assists the movement of the joints of the leg of the person to be supported for walking in order to correct the walking posture of the wearer by the hip joint assist actuator 17, the knee joint assist actuator 18, and the ankle joint assist actuator 19. The posture control means controls the posture of the walking support target by driving the actuator.

  The walking cycle is divided into initial grounding a to free leg end h, and the control device 50 corrects the center of gravity of the wearer's human body for each division, so that the walking cycle is divided into a plurality of periods, The posture control means detects a shift at each time period and controls the posture of the walking support target person.

DESCRIPTION OF SYMBOLS 1 Wearable robot 10 Toe reaction force sensor 11 Toe reaction force sensor 12 Toe posture sensor 13 Waist posture sensor 14 Waist posture sensor 15 Upper leg posture sensor 16 Lower leg posture sensor 17 Hip joint assist actuator 18 Knee joint assist actuator 19 Ankle joint assist actuator 20 Battery (heavy)
DESCRIPTION OF SYMBOLS 21 Lumbar mounting part 22 Upper leg mounting part 23 Lower leg mounting part 24 Foot mounting part 26 Upper leg connection member 27 Lower leg connection member 32 Ideal center of gravity 33 Human body center of gravity 50 Control device 51 Body parameter input part 52 Sensor information acquisition part 53 Various parameter calculation parts 54 Human center of gravity calculation unit 55 Ideal center of gravity calculation unit 56 Center of gravity locus comparison unit 57 Walking assist force determination unit 58 Heavy object slide actuator

Claims (4)

A heavy article moving means for moving a heavy article constituting the walking support device in the left-right direction;
Human body center-of-gravity position acquisition means for acquiring the center-of-gravity position of the walking support target person excluding the heavy object as the human body center-of-gravity position;
Reference centroid position acquisition means for acquiring a reference position of the centroid corresponding to the acquired human body centroid position;
The movement of the heavy object by the heavy object moving means is controlled so that the overall gravity center position of the walking support target person including the heavy object equipped with the walking assistance device is closer to the reference position of the gravity center than the human body gravity center position. Heavy goods movement control means;
A walking support device comprising: The heavy object movement control means controls the heavy object so as to move outside a reference position of the acquired center of gravity.
The walking support apparatus according to claim 1. The heavy object moving means moves, as the heavy object, at least a battery that supplies electric power in the left-right direction.
The walking support apparatus according to claim 1. A walking support program of a walking support device provided with a heavy object moving means for moving a heavy object constituting the walking support device in the left-right direction,
Human body gravity center position acquisition function for acquiring the gravity center position of the walking support target person excluding the heavy object as the human body gravity center position;
A reference center of gravity position acquisition function for acquiring a reference position of the center of gravity corresponding to the acquired human body center of gravity position;
The movement of the heavy object by the heavy object moving means is controlled so that the overall gravity center position of the walking support target person including the heavy object equipped with the walking assistance device is closer to the reference position of the gravity center than the human body gravity center position. Heavy object movement control function,
A walking support program that uses a computer.

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