JP2007054543A - Massaging machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a massaging machine capable of offering more effective massage to a person by changing the direction of massaging pressure to be applied to his/her body region. <P>SOLUTION: In this massaging machine, its multi-joint arm 31 having at least three joints 30 capable of rotary or parallel movements is provided with a massaging element 32 at its end. This massaging machine includes an actuator which drives each joint separately, a displacement detecting sensor which detects any displacement of the joints during their rotary or parallel movements, and a control circuit which drives the actuator. The control circuit drives the massaging element at the end of the arm by using a vector that has been three-dimensionally set to face a desired direction. Therefore, any desired direction can be chosen via the massaging element in applying massaging pressure to a region of a human body. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a massage machine, and more particularly to a massage machine in which a treatment element is arranged at the tip of an articulated arm.

  Traditionally, massage machines with a massage mechanism on the back of the chair have been provided. In these massage machines, the massage mechanism is incorporated on the frame such as the back and the force of the treatment element is perpendicular to the frame surface. It is configured to control the position of the treatment element in a direction parallel to the frame surface.

  On the other hand, for a user who receives massage by applying force through the treatment element in the massage mechanism, the direction in which the force is applied differs depending on the part where the treatment element abuts. In many cases, the conventional massage machine as described above cannot meet such demands.

In addition, since the posture of the user is not fixed, it is difficult to always meet the above demand.
Japanese Patent No. 3402723

  The present invention has been invented in view of the above-described conventional problems, and provides a massage machine that can perform more effective massage by changing the direction in which force is applied to a part of a user. It is another object of the present invention to provide a massage machine capable of performing the massage regardless of the posture of the user.

  In order to solve the above problems, a massage machine according to the present invention is a massage machine in which a massage treatment element is arranged at the tip of an articulated arm formed of at least three or more rotatable or translatable joints, The actuator includes an actuator that independently drives the joint, a displacement sensor that detects the rotational or translational displacement of each joint, and a control circuit that drives the actuator, and the control circuit is set in any orientation in three dimensions. It is characterized in that the treatment element at the tip of the arm is driven by the generated vector. The direction in which force is applied to a certain part of the human body via the treatment element can be made arbitrary.

  The control circuit is configured so that each actuator is based on a deviation between the target value of the arm tip or each joint quality and the current displacement detected by the displacement sensor or the current position of the arm tip calculated from the current displacement detected by the displacement sensor. Preferably, the arm is provided with a force sensor at the tip thereof, and the control circuit has a predetermined force direction and force target value, and the force sensor. It is preferable to include force control means for controlling each actuator on the basis of a deviation from the current value of the force detected by.

  If the storage means for storing the target value is provided, a massage operation such as a massage massage or acupressure massage set in advance can be obtained.

  The arm calculated geometrically from each joint displacement information output from the displacement sensor when the arm tip is in contact with the user and the length information given in advance of the link connected by the joint in the arm With the body shape detection means for detecting the body shape line of the human body to be massaged from the tip position information, it is possible to easily apply a force to each part of the human body in an effective direction.

  In this case, it is preferable that the direction of the vector for driving the treatment element at the end of the arm is set with respect to the tangent line or normal line of the body line detected by the body line detection unit of the human body.

  And if it has the operation part for adjustment of the direction and magnitude | size of the vector which drives the treatment element of the arm front-end | tip, the force of the direction and magnitude | size according to a user's liking can be applied.

  If the position control means includes means for sequentially changing the target locus of the arm tip in the tangential direction of the body shape line, the target locus can always be maintained without depending on the uneven shape of the human body.

  In addition, the direction in which the force is applied to the surface including the target locus in the position control by the position control means is orthogonal, and the force application direction is excluded from the surface parallel to the body line tangent surface and the joint displacement Jacobian in the arm. If feedback position control with the target set on the surface is performed on the treatment element at the tip of the arm, a displacement error in position control does not appear as a force control error.

  Since the present invention drives the treatment element at the end of the arm with a vector set in an arbitrary direction three-dimensionally, the direction in which force is applied to a certain part of the human body via the treatment element is arbitrary. It is possible to perform a more effective massage for each part.

  Hereinafter, the present invention will be described based on an embodiment shown in the accompanying drawings. FIG. 2 shows an example of a massage machine according to the present invention, and a pair of left and right massage mechanisms 3 and 3 are arranged on a backrest 2 of a chair 1. ing. These massage mechanisms 3 and 3 are the treatment elements 32 that contact the human body with the tip of an articulated arm 31 formed of at least three or more rotatable or translatable joints 30. A plurality of the arms 31 are provided side by side for the sake of imitation. Each joint 30 in each arm 31 is provided with an actuator (motor) that is individually driven, and a displacement sensor including a rotary encoder that detects a rotational or translational displacement of each joint 30.

  The joint 30 may have any configuration as long as the treatment element 32 at the tip of the articulated arm 31 can be moved three-dimensionally. In the configuration shown in FIG. The first joint 30 that performs the rotation and the second and third joints 30 and 30 that perform the in-plane rotation including the Z axis include a total of three joints 30.

  As shown in FIG. 4, each motor is connected to a control circuit via a motor driver and a D / A converter, and a displacement sensor (rotary encoder) is connected to the control circuit via a counter. The force sensor in FIG. 4 is arranged on the treatment element 32 at the tip of the arm 31 and measures the contact between the treatment element 31 and the human body and the reaction force when the treatment element 32 presses the human body. It is connected to the control circuit via a D converter. The storage device in FIG. 4 stores a human body shape line calculated based on the output of the force sensor and the output of the displacement sensor, and target values of displacement and force when the treatment element 32 is driven. It is.

  The control circuit drives the articulated arm 31 by performing position and force feedback control shown in FIG. That is, the position gain is Kp, the speed gain is Kv, the force proportional gain is Kfp, the target displacement is qd, the current displacement obtained from the position sensor is q, the position deviation (qd-q) is e1, and the target force is fd. When the current force obtained from the force sensor is f, the force deviation (fd−f) is e2, and the matrix for converting the arm tip force into each motor output is J, the motor command value u is

It is decided by.

  Incidentally, as shown in FIG. 3, the position of the treatment element 32 at the tip of the arm 31 (coordinates x, y, z) is the angle of each joint 30 as q1, q2, q3, and the length of each link in the arm 31. When l1, l2, and l3,

Can be obtained at

  The body shape of the human body is obtained by collecting a plurality of pieces of positional information of the treatment element 32 when the treatment element 32 is determined to be in contact with the human body from the output of the force sensor by bringing the treatment element 32 into contact with different places in the human body. You can know the line. In this case, the body surface parameters a, b, and c may be determined by substituting the position information at three points into the body surface equation z = ax + by + c. Further, by sequentially updating the coordinates of the three points, it is possible to cope with changes in the posture of the user.

  Here, in the massage machine 1 in which the treatment element 32 is provided at the tip of the articulated arm 31, as shown in FIG. 1, a force vector in an arbitrary direction can be applied to a certain part of the user. . In addition, if the body line is detected as described above, the force is applied in the normal direction of the body line or in a direction that forms an angle with the body line even if the above-mentioned part changes or the posture of the user changes. Can be added.

The control for this will be described. From the body surface equation z = ax + by + c, the geometric constraint condition φ (χ) of the hand is given by the following equation. Here, χ is a three-dimensional position vector (χ = (x, y, z) ^T ) of the arm tip (T indicates transposition).

φ (χ) = z-ax-by-c = 0
Therefore, the normal vector φx of the body shape surface is
φx = (∂φ (χ) / ∂χ) ^T
= (∂φ (χ) / ∂x, ∂φ (χ) / ∂y, ∂φ (χ) / ∂z) ^T
It is expressed.

Here, the Jacobian of the arm tip position χ = (x, y, z) ^T and the joint coordinate system q = (q1, q2, q3) ^T is

, The transformation vector J _φ to each joint force (each motor command value) for exerting the force in the normal direction of the body surface is expressed as J _φ (q) ^T = J _x (q) ^T (∂φ / ∂χ) / | φx |
Can be defined in

  This expression is a conversion vector to each joint 30 for exerting a force in the normal direction to the body surface as described above. By changing the body surface parameters a, b, and c, any expression can be obtained. A transformation vector for each joint for exerting a force in the direction can be obtained. Further, by sequentially updating the body surface information, the direction of the force can always be set in the designated direction with respect to the body line.

  Further, an operation unit 4 as shown in FIG. 9 is provided on the armrest of the chair 1 so that the arm 31 outputs the force of the direction and size given by the user using the operation unit 4. May be. The operation unit 4 in the illustrated example detects the direction and strength when the user presses the operation surface 40 with a finger using the triaxial force sensor 41, and the detected strength is a target for the feedback control. By controlling each joint 30 so that the above force can be obtained in the detected direction as well as the force, a massage having the direction and strength desired by the user can be obtained.

  By the way, a control law when performing position feedback control and force feedback control is expressed as follows.

  At this time, when not only pushing into the human body for massaging massage, but also making a movement to move along the body surface of the human body, a target locus is set, and the treatment element 32 follows this locus. The position is controlled so as to move along, but if a plane including this trajectory (the elliptical trajectory t in FIG. 6) is defined as the target trajectory plane T, the target trajectory plane T is always tangential to the body shape line L. Position control is performed while sequentially changing so that. In the figure, M is a contact line between the target locus surface T and the body shape line L, and the target locus t is sequentially changed along the curved surface of the body shape line L.

  The information of the body line is required for the sequential change. Since the normal direction is obtained from the normal vector φx, a coordinate system can be defined on the body line, and the coordinate system can be used for the arm 31. Since it is defined by the contact point between the treatment element 32 at the front end and the user, it is sequentially changed. By defining the target locus plane T in this coordinate system, the target locus t can always be in the tangential direction of the body line L. As a result, it means that the target trajectory t can always be maintained without being affected by the uneven shape of the human body surface.

  In addition, as shown in FIG. 7, when controlling the force in the direction orthogonal to the surface (surface parallel to the body line tangent surface (x, y plane)) P to be controlled, the surface P and the joint The displacement Jacobian (tangential Jacobian) is given by the following equation.

At this time, the target trajectory is given only in the xy direction and can be expressed as xdxy = (xd, yd) ^T, and the position xxy = (x, y) ^T regarding the xy at the tip of the arm 31 is controlled. Since performing force control of seeking transformation vector J _phi same time, the control input is given by the following equation (where, K _pxy position gain, K _Vxy speed gain).

  The reason why no target position value is given in the depth direction of the body shape line is that the displacement error of the position control avoids affecting the force control. FIG. 8 shows a flowchart when the position and force are controlled while detecting the body shape line.

  If the force feedback by the force sensor is included, the control input is as follows.

  A force sensor and body shape line detection means are not necessarily required. This is because even if the articulated arm 31 is driven on the premise of a body shape line given in advance, the direction in which a force is applied to a certain part of the human body via the treatment element can be made arbitrary. FIG. 10 shows a block circuit diagram in this case.

It is operation | movement explanatory drawing in an example of embodiment of this invention. (a) is a perspective view of the same, (b) is an enlarged perspective view of the main part of the same. It is explanatory drawing of an arm same as the above. It is a block circuit diagram same as the above. It is a block diagram of a control system same as the above. It is explanatory drawing of a target locus surface. It is explanatory drawing of position control and force control same as the above. It is a flowchart same as the above. It is the schematic of an operation part same as the above. It is a block circuit diagram of another example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Chair 2 Backrest 3 Massage mechanism 30 Joint 31 Arm 32 Treatment child

Claims (9)

  A massage machine in which a massaging treatment element is arranged at the tip of an articulated arm formed of at least three or more rotatable or translatable joints, and an actuator that independently drives each joint; A displacement sensor for detecting translational displacement and a control circuit for driving the actuator are provided, and the control circuit drives a treatment element at the end of the arm with a vector set in an arbitrary direction three-dimensionally. A massage machine characterized by being.   The control circuit controls each actuator based on the deviation between the target value of the arm tip or each joint quality and the current displacement detected by the displacement sensor or the current position of the arm tip calculated from the current displacement detected by the displacement sensor. The massage machine according to claim 1, further comprising position control means for controlling.   The arm has a force sensor at its tip, and the control circuit controls each actuator based on a deviation between a preset force direction and target force value and the current force value detected by the force sensor. The massage machine according to claim 1, further comprising force control means for performing the operation.   4. The massage machine according to claim 2, further comprising storage means for storing a target value.   Arm calculated geometrically from each joint displacement information output from the displacement sensor when the arm tip is in contact with the user and the length information given in advance of the link connected by the joint in the arm The massage machine according to any one of claims 1 to 4, further comprising body shape detection means for detecting a body shape line of a human body that is a massage target from tip position information.   6. The massage machine according to claim 5, wherein the direction of the vector for driving the treatment element at the tip of the arm is set with respect to a tangent line or normal line of the body line detected by the body line detection means of the human body. .   The massage machine according to claim 6, further comprising an operation unit for adjusting a direction and a size of a vector for driving the treatment element at the tip of the arm.   The massage machine according to any one of claims 5 to 7, wherein the position control means includes means for sequentially changing the target locus of the arm tip in the tangential direction of the body shape line.   The direction in which the force is applied to the surface including the target trajectory in the position control by the position control means is orthogonal, and the force application direction is excluded from the surface parallel to the body line tangent surface and the joint displacement Jacobian in the arm 9. The massage machine according to claim 8, wherein feedback position control with a target set on the surface is performed on the treatment element at the tip of the arm.

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