JP4608661B2 - Stand-up training machine - Google Patents

Description

  The present invention relates to a stand-up training machine, and more specifically, it is possible to effectively perform stand-up training by supporting a stand-up operation only with a force that is insufficient by one's own power when the user stands up. The present invention relates to a stand-up training machine that can also perform a stand-up preparation operation training for lifting a body from a chair and shifting to a stand-up posture.

  Conventionally, when patients who have difficulty getting up on their own due to injury or illness are performing rehabilitation of standing up movements, a health care worker such as a nurse or a physiotherapist is attached to the patient to support the body. However, such conventional rehabilitation has a very heavy physical burden on the medical staff.

Under such circumstances, there has been proposed an apparatus for assisting a patient to stand up alone without requiring an assistant.
As such a device, there are a device that forcibly applies an upward displacement to the patient's body and a device that applies a certain force upward to the patient's body. As an example of the former, there is one that raises the seating surface of a chair (see, for example, Patent Document 1 below). As an example of the latter, there is one that lifts a patient's body with a rope (see, for example, Patent Document 2 below). ).

  However, the method of forcibly applying an upward displacement to the patient's body is difficult to train because it rises automatically regardless of the patient's efforts. On the other hand, in the method of applying a certain upward force to the patient's body, it will be training because it cannot stand up without the patient's effort, but the amount of auxiliary force required for standing up depends on the posture when the patient is sitting. It is difficult to perform effective training because it does not take into account differences or significant changes in the auxiliary power required in the process of getting up.

When the patient stands up, the dynamic center of gravity (the combined force of weight and inertial force) is applied to the sole of the foot at the stage where the body moves away from the chair and stands up with only the power of the feet (hereinafter referred to as a standing posture). If it is not within the range of the length (the length of the sole), it falls.
Therefore, in the rehabilitation of the standing up movement, training for the standing up preparation movement that shifts from the sitting state to the standing posture is also important, but there is no device for performing such training, It is also very difficult for patients to perform such training on their own will.

Japanese Patent Laid-Open No. 9-168565 JP 2002-58712 A

  The present invention has been made to solve the above-described problems of the prior art, and in response to a change in posture when the patient is standing up, only the force necessary for the posture at that time is used. A stand-up training machine that enables effective stand-up training by assisting the stand-up operation, and also allows the user to perform a stand-up preparation exercise for lifting the body from the chair and shifting to the stand-up position. Is to provide.

The invention according to claim 1 comprises lifting means for lifting the user's body upward, and joint moment measuring means for estimating the lower limb joint moment acting at the time of the user's standing motion in real time, the lifting means being A rope suspended from above the user's body and attached to the body; a motor for winding the rope upward; and a tension applied to the rope as a lifting load applied to the user's body A lifting load measuring means and a control means for controlling the driving of the motor. The control means measures the joint moment from the lower limb joint moment necessary for the user to stand up by himself / herself in advance. calculating a difference obtained by subtracting the lower limb joint moments estimated by means, as the difference becomes zero or slightly negative, the motor Adjust the hoisting load by controlling the driving of the motor, if no stand up even after the lapse of a certain user starts to rise operation time, gradually decreases the value of the lower limb joint moment the previously stored in the memory The first correction for gradually increasing the lifting load to replace the lower limb joint moment value when the user can stand up with the lower limb joint moment value stored in the memory in advance. And when the speed and acceleration of the rising motion of the user exceed preset values, the lifting load is gradually decreased by gradually increasing the lower limb joint moment value stored in the memory in advance. The value of the lower limb joint moment when the user can stand up at a speed and acceleration below the set value is stored in the memory in advance. About rising trainer, characterized in that it comprises a second correction means for replacing the value of the lower limb joint moments that.

The invention according to claim 2 is characterized in that the rope includes a plurality of ropes, and the plurality of ropes are arranged so as to lift the user's body upward at different angles. It relates to the stand-up training machine according to Item 1 .

In the invention according to claim 3, the control means calculates the rope angle and the lower end position from the rope length measured based on the rotation angle of the motor, and the locus of the center of gravity of the user's body is natural. The rising training machine according to claim 2, wherein the hoisting machine is wound up while adjusting the angle and the lower end position of each rope by controlling the driving of the motor so as to follow the locus of the center of gravity of the body at the time of standing up .

The invention according to claim 4 relates to the standing-up training machine according to any one of claims 1 to 3 , wherein the motor is driven by the control means by impedance control .

According to a fifth aspect of the present invention, the joint moment measuring means includes a floor reaction force measuring means for measuring a reaction force that the user's sole receives from the floor, and a knee joint, a hip joint, and an ankle joint at the time of the user's rising motion. A joint position measuring means for measuring at least the positions of the knee joint and the ankle joint, and a joint moment calculating means for calculating a joint moment at the time of the user's rising motion based on the measured reaction force and joint position. And a stand-up training machine according to any one of claims 1 to 4 .

The invention according to claim 6 calculates the zero moment point of the body excluding the force that the user receives from the training machine at the start of the rising motion , and the calculated zero moment point is within the range of the sole length of the user. The starter trainer according to any one of claims 1 to 5, further comprising: means for determining whether or not the position is zero or means for displaying the position of the zero moment point in real time .

According to the first aspect of the present invention, the difference obtained by subtracting the lower limb joint moment estimated by the joint moment measuring means from the lower limb joint moment necessary for the user to stand up by himself / herself is zero or slightly negative. By adjusting the lifting load of the user with the rope, the lifting load is adjusted according to the change in posture when the patient is standing up, so it is the same or slightly the force required for the patient's posture at that time The patient's standing motion is assisted with a large force, and effective standing training is possible.

Further , according to the first aspect of the present invention, when the lower limb joint moment necessary for the user to stand up by himself / herself increases, the set value corresponding to the increase can be corrected to assist the rising operation. . Specifically, when the user does not stand up even after a certain period of time after starting the rising motion, the lifting force that assists the rising motion can be increased and adjusted, thus reducing the user's rising ability. Corresponding and effective start-up training can be performed.

Further , according to the first aspect of the present invention, when the lower limb joint moment necessary for the user to stand up by himself / herself is reduced, the set value is corrected corresponding to this decrease to assist the user in the rising motion. be able to. Specifically, when the speed and acceleration during the rising motion of the user exceed the set values, the lifting force that assists the rising motion can be adjusted to decrease, so it corresponds to the increase in the rising ability of the user. Effective start-up training can be performed.

According to the second aspect of the present invention, the rope is composed of a plurality of ropes, and the plurality of ropes are arranged so as to lift the user's body upward at different angles. The posture of the hour can be adjusted satisfactorily.

According to the invention of claim 3 , the angle of each rope and the position of the lower end are controlled by controlling the motor drive so that the locus of the center of gravity of the user's body follows the center of gravity locus of the body at the time of a natural rising motion. Since it winds up while adjusting, the posture of the user when standing up can be made natural.

According to the invention of claim 3 , since the motor is driven by the control means by impedance control, the spring and the damping can be changed by the control parameter, and it is possible to secure the allowance as needed. Become.

According to the invention of claim 4 , the joint moment measuring means is based on the reaction force that the user's sole receives from the floor and the positions of at least the knee joint and ankle joint during the user's standing up motion. The joint moment can be calculated easily and accurately by calculating the joint moment during the start-up operation.

According to the invention according to claim 5 , the zero moment point of the body excluding the force that the user receives from the training machine at the start of the standing motion is calculated, and the calculated zero moment point is the length of the sole of the user's sole. It is possible to stand up when the user performs a stand-up operation by himself / herself by judging whether it is within the range or by displaying the zero-mo point position in real time and seeing it by the user. It is possible to determine whether the posture is achieved and to perform training for shifting to the standing posture. In addition, if the user can see the zero moment point in real time, it is possible to train while learning how the user moves to prepare for a correct rise.

DESCRIPTION OF EMBODIMENTS Hereinafter, a preferred embodiment of a standing-up training machine according to the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram of a stand-up training machine according to the present invention, where arrows in the figure indicate forces acting on the training machine and the user, and vertical downward arrows indicate gravity acting on each part, vertical upwards. The arrows indicate the reaction force acting on each part (the floor reaction force received from the sole, the reaction force from the hand, the reaction force from the chair), and the diagonally upward arrow indicates the tension acting on the rope.

  The standing-up training machine according to the present invention has a lifting means for lifting the body of the user (S) of the training machine sitting on the chair (C) upward, and the lower limb joint moment during the standing-up motion of the user in real time. And a joint moment measuring means estimated in (1).

  The lifting means includes a rope (1) suspended from above the body of the user (S) and attached to the body, and a motor (2) for winding the rope (1) upward of the body. A lifting load measuring means (3) for measuring the tension applied to the rope (1) as a lifting load applied to the user's body, and a control means (4) for controlling the drive of the motor (2) are provided.

The rope (1) is stretched along a roller (6) attached to a substantially Γ-shaped support (5) in side view, and one end of the rope (1) is fixed to the waist of the user (S). The end is connected to the motor (2).
Thus, when the motor (2) rotates forward, the rope (1) is wound up and the body of the user (S) is lifted upward. When the motor (2) rotates backward, the rope (1) is wound. The removal is released and the body of the user (S) is lowered downward.

The rope (1) consists of a plurality (two in the illustrated example).
The roller (6) for converting the direction of each rope (1) to the downward direction is attached to the column (5) with the position shifted back and forth above the user (S). The rope (1) is suspended and fixed to the body of the user (S) at different angles.
Each rope (1) is connected to a separate motor (2) (in the figure, the motor is simplified to one block), and the control means (4) controls the drive of each motor individually. Each rope (1) can be moved up and down individually.

The motor (2) consists of a servo motor with an encoder, and can detect the rotation angle of the motor shaft.
Information on the rotation angle of the motor shaft detected by the encoder is sent to the control means (4) and used to calculate the rope length.

The lifting load measuring means (3) is composed of a load cell interposed in the middle of a portion extending from the support (5) of the rope (1) toward the user (S), and applies tension applied to the rope (1). It is measured as a lifting load applied to the user's body.
The lifting load measuring means (3) may be configured to measure the current value of the motor (2) and calculate the tension based on the current value, instead of the configuration to measure the tension directly applied to the rope by the load cell. .
The lifting load value measured by the lifting load measuring means (3) is sent to the control means (4).

The control means (4) is composed of a computer having a CPU and a memory in which necessary application programs are stored, and the force to suspend the user as the vector sum of the tensions of the plurality of ropes (1) Therefore, the driving of the motor (2) is controlled so that the minimum value necessary for the above-mentioned operation is achieved and the speed and acceleration of the user's rising motion do not exceed preset values.
As a control method, when it is desired to secure the allowance for the user's intention from the target rising trajectory, the position or speed command-based impedance control (position or speed as if there is a spring, damper, or mass) It is recommended to use a control for giving a command.

The control means (4) calculates the rope length based on the rotation angle of the motor (2) as described above, and the angle of each rope (angle with respect to the user) and the lower end based on the calculated rope length. Calculate the position (fixed position to the user).
And each rope (1) is controlled by controlling the drive of the motor (2) so that the locus of the lower end position of the body of the user (S) follows the locus of the lower end position of the body at the time of natural rising motion. Wind up while adjusting the angle and the lower end position.

The trajectory of the lower end position at the time of the natural rising operation of the user needs to be obtained in advance, and the obtained trajectory is associated with the angle of the rope (1) and the lower end position, and is previously controlled by the control means ( 4) is stored in a readable memory.
As a method of obtaining the locus of the lower end position,
・ An expert such as a physiotherapist considers the recovery status and initial posture of the user (patient), makes a stand-up as a model, and obtains the locus of the lower end position by motion analysis etc. using a CCD camera. The trajectory is corrected by the difference in physique from the user.
・ An expert such as a physiotherapist actually supports the user (patient) to stand up, and obtains a locus of the lower end position by motion analysis or the like.
Use a known standard trajectory such as the average trajectory of many people whose age and medical condition are close to the user.
Such a method is conceivable.

  The joint moment measuring means is means for estimating in real time the lower limb joint moment at the time of the user's standing motion, and the floor reaction force measuring means (7) for measuring the reaction force that the user's sole receives from the floor; The joint position measuring means (8) for measuring the positions of the knee joint, the hip joint, and the ankle joint during the user's rising motion, and the joint moment during the user's rising motion based on the measured reaction force and joint position. And a joint moment calculating means (9) for calculating.

FIG. 2 is a schematic diagram showing an extracted lower limb portion of the user.
In the figure, A is an ankle joint, B is a knee joint, and C is a hip joint, and W ₁ , W ₂ , and W ₃ are added to the respective center of gravity positions between A and B, and between B and C, respectively. a load (self-weight), _{F Z} is a reactive force that the user receives from the _floor, is r _a, r b, the horizontal distance _{r c} is the operating position of the respective _{F Z} a, B, and the position of the C .

The floor reaction force measuring means (7) comprises a floor reaction force meter that measures the load position and magnitude of the floor reaction force (F _Z ) that the user receives from the backs of both feet. The left and right feet may be measured independently on the left and right, or the total of both may be measured.
The floor reaction force meter generally measures force and load position in three directions, and can be used as the floor reaction force measuring means (7) in the present invention. What is necessary is just to be able to measure the load and the load position in the direction. Moreover, a stationary floor reaction force meter may be used, or a wearable floor reaction force meter may be used. In a wearable floor reaction force meter, a user wears footwear with a built-in sensor and measures how much vertical load is applied to which position in the coordinates of the user's sole.

Examples of the joint position measuring method by the joint position measuring means (8) include the following methods.
・ A marker is attached to each of the user's ankle joint (A), knee joint (B), and hip joint (C), and these are photographed with a plurality of stationary cameras. How to get the coordinates of
A method in which a marker is attached to each of the user's ankle joint (A), knee joint (B), and hip joint (C), and this is taken with a single camera fixed to a training machine, and the position is measured from the photographed image. .
・ A wearable posture measurement device that can measure tilt (known devices such as a device that can measure the tilt from the vertical by combining an accelerometer and a gyro sensor, or a device that can directly measure the joint angle) is attached to the user. The angle of the ankle joint (A), the knee joint (B), and the hip joint (C) is measured, and the position of each joint portion is sequentially measured from the measured value and the coordinates of a predetermined reference position.

The calculation described later joint moment, r _a, r b in FIG. _2, it requires the value of r _c, of these to determine the value, the positional relationship between the joint position and force plate of the user Information is needed.
When a stationary floor reaction force meter is used as the floor reaction force measuring means (7), information on the positional relationship between the joint position of the user and the floor reaction force meter is obtained by the joint position measuring means (8) described above. Obtained based on measurements.
When a wearable floor reaction force meter is used as the floor reaction force measuring means (7), the coordinates of the sensor of the floor reaction force meter and the sole coordinates of the user coincide with each other. If the user inputs the information on the positional relationship of the reaction force meter when the user wears the floor reaction force meter, it is not necessary to measure it during the rising operation.

When a wearable floor reaction force meter is used, a method using the above-described camera may be used as a joint position measuring method by the joint position measuring means (8), but the above-described user can wear it (wearable). If the method using the posture measuring device is used, all of the information can be handled by the user's coordinates, so that less information is required to calculate the joint moment. However, in this case, in order to calculate the _{r a, r b, r c} , the portion of the first from A, between A-B, previously entered the length between B-C, separately for left and right legs It is necessary to calculate.

  The joint moment calculating means (9) is based on the floor reaction force measured by the floor reaction force measuring means (7) and the joint position of the user measured by the joint position measuring means (8). Calculate the joint moment during operation.

Hereinafter, a method for calculating the joint moment will be described.
Generally, humans (users) are replaced with rigid links as shown in FIG. 1, and the weight of the center of gravity of each part, inertial force due to acceleration of the center of gravity of each part, floor reaction force, reaction force from a chair, rope If the tension is known, the moment acting on each joint (ankle joint, knee joint, hip joint) of the lower limb can be calculated from static balance. Furthermore, if necessary, muscle tension can be estimated from the moment using a muscle / skeletal model.
In the present invention, since attention is paid to the lower limb, information such as the upper limb is not necessary if the calculation is performed in order from the bottom, and external forces applied to the lower limb as shown in FIG. If the position of the center of gravity (between A and B, between B and C), the dead weight, and the inertial force are known, the joint moment of the lower limb can be calculated with high accuracy. However, if it is a static (slow) rise, the inertial force can be ignored.

Hereinafter, a method of calculating joint moments in order from the bottom will be described.
First, as shown in FIG. 3, a free body diagram is drawn for the lowermost foot portion (portion from the ankle (A)).
Since the foot is not inertial force since the stationary input and F _Z measured by the floor reaction force measuring means (7), r _a is determined by the joint position measurement means _(8), as known information Using W ₁ and r ₁ , unknown variables M _A and F _A are calculated from the balance equation of the force and moment in the vertical direction. Specifically, it is calculated by the following formula.
F _A = F _Z −W _{1
M A = F Z r a -W} 1 r 1

Thus obtained M _A is the ankle joint moment. In some cases, it may ignore the influence of W ₁ is small.
If Motomare is F _A and _{M A,} in relation to action and reaction, -F _A and the -M _A is applied to the lower leg (between A-B) as a known external force, unknown variables _M in the same procedure _B and _{F B} , M _B becomes the knee joint moment, and the hip joint moment can also be obtained by the same procedure. If the acceleration is large and the inertial force cannot be ignored, the inertial force can be obtained from the measured acceleration and the estimated mass value, and the balance of the forces can be considered.
Although only the vertical force is used here, if it is necessary to consider the horizontal force, the horizontal force is also measured and calculated by adding a horizontal force balance formula. do it.

The joint moment value obtained by the joint moment calculating means (9) by the method as described above is sent to the control means (4).
The control means (4) calculates the difference between the lower limb joint moment required for the user to stand up by himself / herself and the lower limb joint moment estimated by the joint moment measuring means, and the difference is zero. Alternatively, the lifting load by the rope (1) is adjusted by controlling the drive of the motor (2) so as to be slightly negative.
That is, the drive control of the motor (2) by the control means (4) is performed by a shortage or a little more than the lower limb joint moment necessary for the user to stand up on his own, in other words, only by a shortage of the user's leg strength or The pulling force (lifting force) is applied to the rope (1) by a force slightly larger than the shortage, and this can assist the user to stand up with a minimum force.

  According to the above-described method of calculating the joint moments in order from the bottom, as shown in FIG. 1, an element of the rope tension is added to the balance equation for obtaining the hip joint moment (the rope tension acts on the point C). Therefore, the control means (4) can use this to calculate the necessary lifting load (tensile force).

The lower limb joint moment necessary for the user to stand up by himself / herself is stored in advance in a memory that can be read out by the control means (4). The following three types of methods are conceivable for obtaining the lower limb joint moment.
The first method is a method in which a user (patient) is trained to stand up without lifting with a rope, and the joint moment acting on the user at this time is measured.
The second method is a method using an appropriate value set according to the user's intention.
The third method is to gradually increase the lifting load by the rope after the user stands up and sits on the training machine as much as possible, and the joint moment when the load on the chair becomes zero or starts rising Is calculated and this calculated value is used.
In the present invention, the moment value obtained by any method may be used.

However, the lower limb joint moment obtained by the above-described method and stored in the memory in advance is not always constant and may vary depending on the situation. That is, the rising ability of the user may increase or decrease depending on the situation.
Therefore, it is preferable that the standing-up training machine according to the present invention is provided with the following two correction means so that even when the lower limb joint moment required when the user stands up by himself / herself changes depending on the situation.

The first correction means gradually reduces the lifting load by gradually reducing the value of the lower limb joint moment stored in the memory in advance when the user does not stand up even after a lapse of a certain time since the start of the rising motion. The lower limb joint moment value when the user can stand up is replaced with the lower limb joint moment value stored in the memory in advance.
When the speed and acceleration of the rising motion of the user exceed preset values, the second correcting means gradually increases the value of the lower limb joint moment stored in the memory in advance to increase the lifting load. It is means for gradually decreasing and replacing the value of the lower limb joint moment when the user can stand up at a speed and acceleration below the set value with the value of the lower limb joint moment stored in advance in the memory.
The speed and acceleration set in advance are set according to the user's rising ability and stored in a memory readable by the control means (4).

  The first correction means corrects a setting value corresponding to the increase (a value of the lower limb joint moment previously stored in the memory) when the lower limb joint moment necessary for the user to stand up by himself / herself increases. Is. As a result of this correction, when the user does not stand up after a certain period of time after starting the standing up motion, the lifting force that assists the standing up motion is increased and adjusted, and the training for rising corresponding to the decrease in the rising ability of the user is performed. Can be done.

  When the lower limb joint moment necessary for the user to stand up by himself / herself is reduced, the second correction means corrects a setting value corresponding to the decrease (a value of the lower limb joint moment stored in the memory in advance). Is. With this correction, when the speed and acceleration during the user's rising motion exceed the set values, the lifting force that assists the rising motion is adjusted to decrease, and the training for rising corresponding to the increase in the user's rising capability is performed. Is possible.

  These two correction means are configured as one of control programs executed by the control means (4), and the replacement of the lower limb joint moment values is automatically executed by the control means (4). However, in the present invention, the lower limb joint moment value may be replaced by manually inputting the set value again.

  The drive control of the motor (2) by the control means (4) is performed so that the rope (1) once lifted does not reverse for safety, and the user is not lifted higher than the standing state. Done. Further, as described above, the speed and acceleration of the rising motion of the user are performed so as not to exceed preset values.

As described above, according to the standing-up training machine according to the present invention, it is possible to support the standing-up motion. However, the action of getting up from a sitting state is
A. B. Preparation for posture to stand up Since it consists of two stages of standing up motion, it is important and effective to perform posture preparation training for standing up in standing up training.

Therefore, in the stand-up training machine according to the present invention, it is preferable to provide a function for performing posture preparation training for standing up.
Such a function is used to calculate the zero moment point of the body excluding the force that the user receives from the training device at the start of the rising motion, and the calculated zero moment point is the length of the sole of the user. It is realized by providing a means for determining whether or not it is within the range of the above, or a means for displaying the position of the zero-mo-point in real time and allowing the user to see it.

There are roughly the following two methods for calculating the zero moment point of the user's body at the start of the rising motion.
1) Obtain from the sum of external forces applied to the user.
2) Calculate by calculating gravity and inertial force from user's posture and movement.
Since these two forces are balanced, they may be calculated by any method, but each method will be described in more detail below.

First, the first method will be described.
As shown in FIG. 4, the external force applied to the body of the user sitting in the chair is the floor reaction force F ₁ , the reaction force F ₂ from the chair, the reaction force F ₃ from the hand, and the tension F ₄ from the rope. For these four forces, the magnitude of the vertical force and the horizontal force and the load position are obtained. In the drawing, the floor reaction force and the horizontal force of the chair reaction force are not shown.

Size and load position of the vertical force and horizontal force of the floor reaction force F ₁ can be measured using a force plate of the above-mentioned floor reaction force measuring means (7). In addition, since the load position of a horizontal force is a floor surface and is known, what is necessary is just to measure positive / negative and magnitude | size about a horizontal force. However, this force can be calculated without measurement.
Tension from the rope F ₄ can be measured using a lifting load cell load measuring means (3). Further, as described above, the control means (4) can calculate the rope length, the rope angle (angle to the user), and the lower end position (fixed position to the user). based on, it is possible to calculate the size and load position of the vertical force and horizontal force of F _4.

Size and load position of the vertical force and horizontal force of the reaction force F ₂ from the chair, can be measured by placing a reaction force gauge similar to the force plate as described above on the seat surface of the chair. In addition, since the load position of the horizontal force is the seating surface and is known, what is necessary is just to measure positive / negative and magnitude | size about a horizontal force.
Size and load position of the vertical force and horizontal force of the reaction force F ₃ from hand, by installing the same reaction force gauge and force plate as described above to the surface of the part to get a hand (armrests, etc.) Can be measured. In the case where not apply pressure by hand, F ₃ are not used.

となる。これを使用者の自重Ｗで割ると、

となる。これが、近似的に立ち上がり補助がない場合のゼロモーメントポイントであり、原点Ｏからの位置を示す。 For the above four forces F _{1 to} F ₄ , the component force in the vertical direction (y direction) and the horizontal direction (x direction) of the i-th force is expressed as F _ix and F _iy using the xy coordinates in FIG. When the load position is expressed as x _i and y _i , the moment M around the point O (the center of the sole length of the user's foot) due to all external forces is

It becomes. When this is divided by the user's own weight W,

It becomes. This is a zero moment point when there is approximately no assistance for rising, and indicates a position from the origin O.

自重Ｗで割れば、

となる。これが、近似的に立ち上がり補助がない場合のゼロモーメントポイントであり、原点Ｏからの位置を示す。 Next, the second method will be described.
In the case of determination from the posture, the gravity center position and gravity can be obtained by adding the gravity of each part in consideration of the gravity center position. When standing up with momentum with your hands etc., you should consider the balance of forces in consideration of the inertial force.
Assume that the user's body is a collection of rigid links as shown in FIG.
It is assumed that the mass m _{i of} the center of gravity of the i-th link and the moment of inertia J _i around the center of gravity. If the position and angle of the center of gravity are x _i , y _i , θ _i , the moment around the point O by all links is

If you divide by its own weight W,

It becomes. This is a zero moment point when there is approximately no assistance for rising, and indicates a position from the origin O.

The control means (4) calculates the zero moment point of the user's body at the start of the rising motion by one of the two methods described above, and then the calculated zero moment point is the user's sole length. It is determined whether it is within the range. This determination result can be notified to the user by displaying on a display attached to the training machine, generating a sound such as a buzzer, or the like.
If it is determined that the zero moment point is within the range of the sole length, it can be considered that the robot can stand up without falling down roughly. However, if it is outside the range of the sole length, it cannot be supported by the foot. In other words, it can be said that the distance between the center O of the sole and the zero moment point is approaching a posture that does not fall without assistance as the distance approaches zero, that is, the posture preparation operation for standing up is performed well. .

Moreover, in this invention, you may comprise so that a control means (4) may display the position of the calculated zero motor point on the display attached to the training machine in real time.
With such a configuration, since the user can see the zero moment point in real time, it is possible to train while learning how to make a preparation for a correct rise.

は一般的な表現であるが、手の力なし、ロープからはまだ吊り上げていない状態でのトレーニングで静かな動きであれば、床反力と椅子からの反力の鉛直成分Ｆ_１ｙ，Ｆ_２ｙ（荷重位置はそれぞれ，ｘ_１，ｘ_２）のみを考慮し、その合力の荷重位置

と足裏長の関係により近似的に評価することができる。 In the first method,

Is a general expression, but if the movement is quiet with no hand force and not yet lifted from the rope, the vertical components F _1y and F _{2y of the} floor reaction force and the reaction force from the chair (Load positions are x ₁ and x ₂ , respectively), and the resultant load position

Can be approximately evaluated by the relationship between the length of the foot and the sole length.

とみなして、

とすればよい。 In the second method,
For static and slow movements, approximately

As

And it is sufficient.

  As described above, by calculating the zero moment point of the user's body at the start of the rising motion, and determining whether the calculated zero moment point is within the range of the sole length of the user, Or, by looking at the zero moment point displayed in real time, it is possible to determine whether or not the user is ready to stand up and approaching such a posture when the user performs a stand-up operation by himself. It is possible to perform training for transition to a standing posture.

  The stand-up training machine according to the present invention is preferably used for training of stand-up and stand-up preparation operations for patients who have difficulty standing up on their own due to injury or illness. It can also be used as support equipment when moving.

It is a mimetic diagram of the standup training machine concerning the present invention. It is a schematic diagram which extracts and shows the leg part of the user of a standing-up training machine. It is a figure for demonstrating the calculation method of the joint moment by a joint moment calculation means. It is a figure which shows the external force added to the user's body in the state of sitting in the chair. It is the figure which assumed that a user's body was a set of rigid body links.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rope 2 Motor 3 Lifting load measurement means 4 Control means 7 Floor reaction force measurement means 8 Joint position measurement means 9 Joint moment calculation means S

Claims (6)

A lifting means for lifting the user's body upward, and a joint moment measuring means for estimating in real time the lower limb joint moment that acts when the user stands up,
The lifting means includes a rope suspended from above the user's body and attached to the body, a motor for winding the rope upward, and tension applied to the rope to the user's body. A lifting load measuring means for measuring as a lifting load, and a control means for controlling the driving of the motor,
The control means calculates a difference obtained by subtracting the lower limb joint moment estimated by the joint moment measuring means from the lower limb joint moment necessary for the user to stand up by himself / herself, and the difference is zero. Or, the driving load of the motor is controlled so as to be slightly negative, and the lifting load is adjusted ,
When the user does not stand up even after a certain period of time has elapsed since the user started the rising motion, the lifting load is gradually increased by gradually decreasing the value of the lower limb joint moment stored in the memory in advance. First correction means for replacing the value of the lower limb joint moment when the limb is able to stand up with the value of the lower limb joint moment stored in advance in memory;
When the speed and acceleration of the rising motion of the user exceed preset values, the lifting load is gradually decreased by gradually increasing the value of the lower limb joint moment stored in the memory in advance. A second correcting means for replacing a value of the lower limb joint moment when the person can stand up at a speed and acceleration equal to or lower than the set value with a value of the lower limb joint moment stored in advance in a memory; rising trainer, characterized in that there. The rope is composed of a plurality of ropes,
  The standing-up training machine according to claim 1, wherein the plurality of ropes are arranged so as to lift the user's body upward at different angles. The control means calculates a rope angle and a lower end position from a rope length measured based on a rotation angle of the motor,
  Winding up while adjusting the angle and the lower end position of each rope by controlling the drive of the motor so that the locus of the center of gravity of the user's body follows the center of gravity locus of the body at the time of natural rising motion The stand-up training machine according to claim 2. The start-up training machine according to any one of claims 1 to 3, wherein the motor is driven by the control means by impedance control. The joint moment measuring means is
  Floor reaction force measuring means for measuring the reaction force that the user's sole receives from the floor;
  A joint position measuring means for measuring the position of at least the knee joint and the ankle joint among the knee joint, the hip joint, and the ankle joint at the time of standing up by the user;
  Based on the measured reaction force and joint position, a joint moment calculating means for calculating a joint moment at the time of the user's standing motion;
The stand-up training machine according to any one of claims 1 to 4, further comprising: Calculate the zero moment point of the body excluding the force that the user receives from the training machine at the start of the rising motion, and determine whether the calculated zero moment point is within the range of the sole length of the user The start-up training machine according to any one of claims 1 to 5, further comprising means for displaying the position of the zero moment point in real time.

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