JP6432171B2 - Driving device and driving method thereof - Google Patents

Description

  The present invention relates to a drive device.

  Conventionally, like the finger movement assist device of Patent Document 1 and the wearable movement support device of Patent Document 2, it is worn on the hand and assists the movement of the finger in the worn state, that is, the finger joint is bent (stretched or bent). There has been proposed a drive device for extension.

JP 2002-345861 A JP 2011-115248 A

  However, in any of the above prior arts, it is possible to control the posture position of the finger on which the drive device is mounted, but the wearer is trying to bend the finger or extend the finger. There is a problem that it is difficult to detect the movement state of the finger, and it is difficult to detect the will of the wearer regarding the movement of the finger. For this reason, there is a problem that it is difficult to appropriately assist (assist) the bending and stretching operation of the finger. These problems are not only drive devices that assist the movement of human finger joints, but also drive devices that assist the movement of each part such as toes, elbows, wrists, knees, neck, waist, etc. This is a common problem. Further, it is a common problem not only in humans but also in driving devices that assist the movement of parts of a living body such as an animal, or a movement other than a living body such as a robot.

SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms.
According to one aspect of the invention, a drive device is provided. The drive device is a mounting mechanism that is mounted on a mounted portion having a first portion and a second portion that are relatively rotated by a joint, the first base portion corresponding to the first portion, and the second portion. A mounting mechanism having a second base portion corresponding to the portion; an actuator for driving the second base portion relative to the first base portion; and between the second base portion and the second portion. And a plurality of first force sensors arranged along a direction perpendicular to the rotation axis of the joint. The actuator is mounted on the basis of a direction of movement of the mounted portion according to a sum of a plurality of first detection values obtained from the plurality of first force sensors that change according to movement of the mounted portion. Drive the mechanism.
In the drive device of this form, when the mounted part to which the mounting mechanism is mounted is moved, the bias and distribution of the force generated between the mounting mechanism and the mounted part depending on the position of the mounted part, Since it can be detected by a plurality of first force sensors, the force generated between the mounting mechanism and the mounted part can be detected with high accuracy, and the state of movement of the mounted part to which the mounting mechanism is mounted Can be detected with high accuracy.
In addition, the present invention can be realized as the following forms.

(1) According to one form of this invention, the drive device for assisting the motion of a biological body is provided. The drive device includes: a mounting mechanism that is mounted on the mounted portion; an actuator that drives the mounting mechanism; and a plurality of first force sensors that are disposed between the mounting mechanism and the mounted portion. . In the driving device of the above form, when the mounted part to which the mounting mechanism is mounted is moved, the bias and distribution of the force generated between the mounting mechanism and the mounted part depending on the position of the mounted part, Since it can be detected by a plurality of first force sensors, the force generated between the mounting mechanism and the mounted part can be detected with high accuracy, and the state of movement of the mounted part to which the mounting mechanism is mounted Can be detected with high accuracy.

(2) In the driving device according to the above aspect, the actuator drives the mounting mechanism based on a plurality of first detection values obtained from the plurality of first force sensors that change according to movement of the mounted portion. You may make it do. According to the driving device of this aspect, based on the plurality of first detection values obtained by the plurality of first force sensors, the movement state of the mounted portion on which the mounting mechanism is mounted is detected with high accuracy, and The mounting mechanism can be driven according to the state of movement of the mounting portion. Thereby, operation | movement of a to-be-mounted part can be assisted.

(3) The drive device according to the above aspect may further include at least one second force sensor arranged to face the plurality of first force sensors with the mounted portion interposed therebetween. According to the driving device of this aspect, it is also possible to detect the force generated between the mounting mechanism and the mounted portion on the second force sensor side disposed opposite to the first force sensor with the mounted portion interposed therebetween.

(4) In the driving device according to the above aspect, the actuator may include a plurality of first detection values obtained from the plurality of first force sensors and at least one second detection value obtained from the at least one second force sensor. The mounting mechanism may be driven based on a plurality of first detection values and at least one second detection value that change according to the movement of the mounted portion. According to the driving device of this aspect, the mounting is performed based on the plurality of first detection values by the plurality of first force sensors arranged opposite to each other with the mounted portion interposed therebetween and the second detection value by at least one second force sensor. The state of movement of the mounted portion to which the mechanism is mounted can be detected with high accuracy, and the mounting mechanism can be driven in accordance with the state of movement of the mounted portion. Thereby, operation | movement of a to-be-mounted part can be assisted.

(5) The drive device according to the above aspect may include a plurality of second force sensors arranged to face the plurality of first force sensors with the mounted portion interposed therebetween. According to the driving device of this aspect, the distribution of contact force between the mounting mechanism and the mounted portion on the first force sensor side is detected by the plurality of first force sensors, and is opposite to the first force sensor. A plurality of second force sensors detect the bias and distribution of the force generated between the mounting mechanism and the mounted part depending on the position of the mounted part on which the mounting mechanism on the second force sensor side is mounted. Therefore, the force generated between the mounting mechanism and the mounted part can be detected with higher accuracy. Then, based on the plurality of first detection values by the plurality of first force sensors and the second detection value by the plurality of second force sensors, the state of movement of the mounted portion to which the mounting mechanism is mounted is detected with higher accuracy. Then, the mounting mechanism can be driven according to the state of movement of the mounted portion. Thereby, operation | movement of a to-be-mounted part can be assisted.

(6) In the driving device of the above aspect, a pressure receiving plate may be provided between the plurality of first force sensors and the mounted portion so as to be in contact with the plurality of first force sensors. . According to the drive device of this aspect, the force generated between the assist drive device and the mounted portion can be efficiently transmitted to the plurality of first force sensors via the pressure receiving plate. It is possible to improve the contact force detection accuracy.

(7) In the driving device according to the aspect described above, the attached portion may be a finger, and the plurality of first force sensors may be arranged at least along the longitudinal direction of the finger on the dorsal side of the finger. According to this type of drive device, it is possible to detect the bias and distribution of the force generated between the mounting mechanism and the finger with high accuracy, and to detect the movement state of the finger with the mounting mechanism with high accuracy. And a mounting mechanism can be driven according to the state of movement of a finger. Thereby, the operation of the finger can be assisted with high accuracy.

(8) In the driving device according to the above aspect, the actuator includes a piezoelectric driving device that generates a driving force for driving the mounting mechanism; the piezoelectric driving device includes a diaphragm having a first surface and a second surface; A vibrating body disposed on at least one of the first surface and the second surface of the diaphragm; the vibrating body includes a piezoelectric body, a first electrode sandwiching the piezoelectric body, and You may make it have a 2nd electrode. According to the drive device of this aspect, the actuator can be made simple, small and thin, and thus the drive device can be reduced in size and thickness.

  The present invention can be realized in various forms such as a driving method for driving the driving device as well as the driving device.

It is a perspective view which shows the use condition of the finger joint drive device of 1st Embodiment. It is the sectional view on the AA line in FIG. It is sectional drawing which shows the state which bent the finger from the state shown in FIG. It is explanatory drawing which shows an example of the actuator shown in FIG. It is explanatory drawing shown about the operation principle of a piezoelectric drive device. It is a flowchart shown about the control processing according to the output of the some 1st force sensor and one 2nd force sensor which a control part performs. It is explanatory drawing shown about the effect by arrange | positioning a some 1st force sensor. It is sectional drawing of the finger joint drive device of 2nd Embodiment. It is a flowchart shown about the control processing according to the output of the some 1st force sensor and the some 2nd force sensor which a control part performs. It is sectional drawing of the finger joint drive device of 3rd Embodiment. It is a flowchart shown about the control processing according to the output of the some 1st force sensor which a control part performs.

  Hereinafter, as an example of the driving device of the present invention, a finger joint driving device that is attached to a finger as a mounting portion and assists (assisted) the movement of the finger to bend or extend will be described.

A. First embodiment:
FIG. 1 is a perspective view showing a usage state of the finger joint drive device 1 of the first embodiment. 2 is a cross-sectional view taken along line AA in FIG. FIG. 3 is a cross-sectional view showing a state in which a finger is bent from the state shown in FIG.

  The finger joint driving device 1 is attached to a hand 100 such as a person who has trouble in bending and stretching a finger due to an accident or illness, a person who has a weak grip, or an elderly person whose strength has weakened due to aging. Is assumed. In the present embodiment, the finger joint driving device 1 is attached to the index finger 101 and is used to assist bending and stretching (that is, rotation) of the finger joint of the index finger 101. This finger joint drive device 1 includes a first base part 2, a first link part 3, a second link part 4, and a second base part 5, and these members are directed from the wrist side to the fingertip side. Are connected in order. These four members 2 to 5 are also referred to as “first member 2”, “second member 3”, “third member 4”, and “fourth member 5”. As shown in FIG. 1, the finger joint driving device 1 further includes an actuator 6 </ b> A and a control unit 10.

  The first base portion 2 is disposed on the back 105 side of the proximal joint 102 of the index finger 101 in the mounted state. The first base portion 2 is a member that forms a block shape with a flat outer shape. The first base portion 2 is attached to the base joint 102 of the index finger 101 using the first attachment band 20A. The first mounting band 20 </ b> A is configured by a band whose length can be adjusted, and each end portion 201 is fixed to each side surface 22 of the first base portion 2. The first wearing band 20A wraps around the palm 106 side of the base 102 of the index finger 101, that is, the back side of the paper surface of FIG. 2 is prevented from leaving the base 102.

  The second base portion 5 is disposed on the fingertip side of the first base portion 2, that is, on the back 105 side of the middle joint 103 of the index finger 101. The second base portion 5 is a member that forms a block shape with a flat outer shape. Similarly to the first base portion 2, the second base portion 5 is attached to the middle joint 103 of the index finger 101 using the second attachment band 20 </ b> B.

The first link part 3 is provided on the fingertip side of the first base part 2. The first link portion 3 is a member whose overall length is longer than the overall length of the first base portion 2 and the second base portion 5. The first link portion 3 includes a top plate 31 and side walls 32 protruding from both edge portions of the top plate 31. The first base portion 2 is sandwiched between the two side walls 32. In addition, each side wall 32 and the side surface 22 of the first base portion 2 are connected via the rotation support portion 11. The rotation support portion 11 is configured by a shaft (not shown) provided on one of the side wall 32 and the first base portion 2 and a bearing (not shown) provided on the other and having the shaft inserted therein. Yes. Further, when assuming a rotation axis O ₁₀₇ when the proximal interphalangeal joint 107 between the proximal node 102 and the middle node 103 of the index finger 101 rotates by bending and stretching, the rotation axis of the rotation support portion 11 is assumed. O ₁₁ is parallel to the rotation axis O ₁₀₇ . The pivot support portion 11 having such a configuration, the first link portion 3 can be rotated in the rotation axis O ₁₁ around the first base portion 2.

  The second link part 4 is provided on the fingertip side of the first link part 3. The second link part 4 has a sliding part 41 that slides with respect to the second base part 5 and a protruding part 42 that protrudes from the sliding part 41.

  As shown in FIGS. 2 and 3, the sliding portion 41 of the second link portion 4 is a cylindrical portion having a hollow portion 411, and the rail portion 53 of the second base portion 5 is inserted through the hollow portion 411. doing. The total length of the rail portion 53 is set sufficiently longer than the total length of the sliding portion 41. By sliding the sliding portion 41 while being guided by the rail portion 53, the second base portion 5 can be moved closer to and away from the first base portion 2. FIG. 2 shows a state in which the second base portion 5 is close to the first base portion 2, that is, a state in which the index finger 101 is opened by extending the proximal interphalangeal joint 107. FIG. 3 shows a state in which the second base portion 5 is separated from the first base portion 2, that is, a state in which the index finger 101 is bent by bending the proximal interphalangeal joint 107.

The protruding part 42 of the second link part 4 is sandwiched between the two side walls 32 of the first link part 3, and the protruding part 42 and each side wall 32 are connected via the rotation support part 12. Has been. The rotation support unit 12 includes a shaft (not shown) provided on one of the projecting portion 42 and the side wall 32 and a bearing (not shown) provided on the other and having the shaft inserted therein. Further, the rotary shaft _{O 12} of the pivot support portion 12 is parallel to the rotation axis _{O 107.} With the rotation support portion 12 having such a configuration, the second link portion 4 can rotate about the rotation axis O ₁₂ parallel to the rotation axis O ₁₀₇ , similarly to the first link portion 3. By rotation axis O ₁₁ and the rotation shaft O ₁₂ is to be parallel to each pivot axis O _107, to facilitate proximal interphalangeal joint 107 with a finger joint driving device 1, i.e., between the proximal phalangeal The joint 107 can be bent and stretched while preventing an excessive force from being applied to the joint 107.

  The constituent materials of the first base part 2, the first link part 3, the second link part 4, and the second base part 5 are not particularly limited, and for example, various resin materials such as polyethylene, aluminum, and the like. Various metal materials can be used. Moreover, it does not specifically limit as a constituent material of mounting band 20A, 20B, For example, various rubber materials, such as a silicone rubber, can be used.

  As shown in FIGS. 2 and 3, a plurality of (two in the illustrated example) first force sensors S <b> 1 are arranged along the longitudinal direction of the index finger 101 on the back surface 51 of the middle joint 103 of the second base portion 5. A pressure receiving plate Ps extending over the plurality of first force sensors S1 is provided on the plurality of first force sensors S1. In addition, one second force sensor S2 is disposed on the ventral surface of the middle joint 103 of the second wearing band 20B. That is, the first force sensor S1 and the second force sensor S2 are opposed to each other with the middle joint 103 interposed therebetween. The first force sensor S1 and the second force sensor S2 are preferably disposed to face each other along the direction in which the index finger 101 rotates. The reason why this arrangement is preferable is that, as will be described later, when a person tries to bend and stretch the index finger 101, it is easy to estimate the intention of bending and stretching based on the detection values of the first force sensor S1 and the second force sensor S2. It is. However, the arrangement is not limited to this, and the first force sensor S1 is arranged on the dorsal side of the finger, and the second force sensor S2 is arranged on the ventral side of the finger with the finger 101 (the middle joint 103) interposed therebetween. It only has to be.

  The plurality of first force sensors S1 is a force applied from the surface 51 side of the second base portion 5 to the back side of the middle joint 103 when assisting the rotation of the proximal interphalangeal joint 107 by an actuator 6A described later. And a force sensor for detecting a force applied from the back side of the middle section 103 to the surface 51 side of the second base portion 5. One second force sensor S2 is a force applied from the ventral side of the middle node 103 to the second wearing band 20B side, and when the forefinger 101 grasps the grasped object (not shown), the second attached from the grasped object. This is a force sensor for detecting the force applied to the ventral side of the middle node 103 via the band 20B. The pressure receiving plate Ps suppresses the dispersion of the force applied from the surface 51 of the second base portion 5 to the back side of the middle joint 103 and the force applied from the back side of the middle clause 103 to the surface 51 side of the second base portion 5. The two first force sensors S1 are provided so as to be efficiently transmitted. However, this pressure receiving plate Ps can be omitted. In addition, the force applied from the surface 51 side of the second base portion 5 to the back side of the middle joint 103 and the force applied from the back side of the middle clause 103 to the surface 51 side of the second base portion 5 are described below. This is also referred to as “force generated between the second base portion 5 and the middle clause 103 of the index finger 101”.

  The detection values of the plurality of first force sensors S1 and one second force sensor S2 are used for controlling the operation of the actuator 6A by the control unit 10. The control unit 10 controls the operation state of the actuator 6A based on the detection values of the two first force sensors S1 and one second force sensor S2, specifically, the rotation state of the first link unit 3, The proximal interphalangeal joint (second joint) 107 is bent and extended.

  FIG. 4 is an explanatory diagram showing an example of the actuator 6A shown in FIG. In the following, for convenience of explanation, the front side of the sheet in FIG. 4 is referred to as “front side” and the opposite side is referred to as “back side”. The actuator 6 </ b> A is a mechanism unit that applies force to the shaft of the rotation support unit 11 when the first link unit 3 rotates with respect to the first base unit 2. The actuator 6A includes a first rotor 61 concentrically connected to the axis of the rotation support portion 11, a second rotor 62 that rotates the first rotor 61, a third rotor 63 that rotates the second rotor 62, and a first rotor 61. 3 A piezoelectric drive device 64 for rotating the rotor 63 is provided. The first rotor 61, the second rotor 62, and the third rotor 63 constitute a set of gear trains. When the third rotor 63 is rotated by the piezoelectric driving device 64, the first rotor 61 is rotated accordingly. . Further, the shaft of the rotation support portion 11 rotates according to the rotation of the first rotor 61, and the first link portion 3 rotates relative to the first base portion 2 according to this.

  The piezoelectric drive device 64 is a laminated body having two sets of vibration structures 65 including five piezoelectric elements 651 and a vibration plate 66 inserted and bonded between them. The vibrating structure 65 is also referred to as “vibrating body 65”.

  Each of the five piezoelectric elements 651 of the vibration structure 65 includes a piezoelectric body and a first electrode and a second electrode that sandwich the piezoelectric body (not shown). Note that one of the first electrode and the second electrode may be a common electrode. These piezoelectric elements 651 are electrically connected to the control unit 10 (FIG. 1). Note that it is sufficient that at least one piezoelectric element 651 is included in the vibration structure 65, and various other elements can be used for the number and arrangement. The vibration structure 65 may be provided on at least one of the two surfaces (first surface and second surface) of the vibration plate 66.

  A protrusion 67 is provided at the end of the piezoelectric driving device 64. A plurality of support portions 68 for supporting the piezoelectric drive device 64 are provided on both side surfaces of the piezoelectric drive device 64. These support portions 68 are formed integrally with the diaphragm 66. In addition, it is preferable that the plurality of support portions 68 protruding from the same side surface of the diaphragm 66 are connected via a connecting plate 69.

  FIG. 5 is an explanatory diagram showing the operation principle of the piezoelectric drive device 64. The piezoelectric driving device 64 operates when the projection 67 of the piezoelectric driving device 64 expands or contracts or elliptically moves when a voltage is applied to the piezoelectric element 651 of each piezoelectric driving device 64 at a constant period. That is, as shown in FIG. 5A, when a voltage having a specific frequency is applied to a pair of two piezoelectric elements 651 located diagonally to each other, the piezoelectric driving device 64 bends to meander (S The tip of the protrusion 67 reciprocates in a specific direction or elliptically moves. As a result, the third rotor 63 (FIG. 4) in contact with the protrusion 67 rotates in a predetermined direction. As shown in FIG. 5B, when a voltage having a specific frequency is applied to another set of piezoelectric elements 651, the third rotor 63 rotates in the reverse direction. Such an operation of the piezoelectric driving device 64 (or the vibrating structure 65) is described in the prior art document (Japanese Patent Application Laid-Open No. 2004-320979 or the corresponding US Pat. No. 7,224,102). The disclosure is incorporated by reference.

  As described above, in the finger joint driving device 1, the first link unit 3 using the piezoelectric driving device 64 can be reliably rotated. In addition, the piezoelectric driving device 64 can realize a reduction in size and thickness of the finger joint driving device 1.

  The control unit 10 (FIG. 1) controls the operation of the actuator 6A based on a program stored in advance, and, as will be described later, according to the detection values of the first force sensor S1 and the second force sensor S2. The operation of the actuator 6A is controlled. The control unit 10 is built in, for example, the second link unit 4 together with a battery (not shown) such as a button cell. The configuration of the control unit 10 is not particularly limited. For example, the control unit 10 may be realized as a dedicated circuit, or a circuit configuration including a microprocessor and a memory may be employed.

  The operation of the finger joint drive device 1 having the above-described configuration will be schematically described. In the state shown in FIG. 2, in the finger joint driving device 1, the first base portion 2 is attached to the base joint 102 of the index finger 101, and the second base portion 5 is attached to the middle joint 103. When the actuator 6A operates so as to rotate the first link portion 3 with respect to the first base portion 2 from this state, the first link portion 3 and the second link portion 4 are shown in FIG. Can be rotated counterclockwise. As a result, the middle joint 103 of the index finger 101 is pressed together with the second base portion 5 obliquely downward and to the right in FIG. As a result, the proximal interphalangeal joint 107 of the index finger 101 is bent and can be moved in the direction in which the index finger 101 is gripped. Further, when the first link portion 3 is rotated clockwise from the state shown in FIG. 3, the middle joint 103 of the index finger 101 is moved upward and diagonally to the left in the drawing together with the second base portion 5 as shown in FIG. Pulled towards. As a result, the proximal interphalangeal joint 107 of the index finger 101 extends, and the index finger 101 can be moved in the opening direction. When the proximal interphalangeal joint 107 is bent (or extended), the second base portion 5 is separated (or approached) from the first base portion 2, but as described above, the second link portion 4 and the second base portion 5 are relatively movable, so that the second base portion 5 is separated (or approached) from the first base portion 2 quickly and smoothly. Thereby, the proximal interphalangeal joint 107 can be easily bent, and the burden on the index finger 101 is reduced.

  In addition, the wearer (user) of the finger joint driving device 1 is connected to the distal interphalangeal joint 109 of the index finger 101 without assistance of the finger joint driving device 1, the thumb, the middle finger, the ring finger, and the little finger (see FIG. 1). ) Can be bent and extended independently of the proximal interphalangeal joint 107 of the index finger 101.

  Further, in the finger joint drive device 1 in the worn state, the first base portion 2 is disposed at the base joint 102 of the index finger 101 and the second base portion 5 is disposed at the middle joint 103 in this embodiment. It is not limited to a simple arrangement. For example, the first base portion 2 may be disposed on the back 105 of the hand and the second base portion 5 may be disposed on the proximal joint 102 of the index finger 101 in the mounted state. In this case, the finger joint driving device 1 can bend and stretch the metacarpophalangeal joint (third joint) 108. In addition, the first base portion 2 may be disposed at the middle joint 103 of the index finger 101 and the second base portion 5 may be disposed at the last joint 104 in the mounted state. In this case, the distal interphalangeal joint (first joint) 109 can be bent and stretched by the finger joint driving device 1. Further, in the mounted state, the first base portion 2 is disposed at the middle joint 103 of the index finger 101, and the second base portion 5 is located on the opposite side of the fingertip from the first base portion 2, that is, on the wrist joint 102. It may be arranged. In this case, the proximal interphalangeal joint 107 can be bent and stretched by the finger joint driving device 1 as in the wearing state of the present embodiment.

  In addition, the attachment position (attached part) to the hand 100 of the finger joint driving device 1 is the index finger 101 in the present embodiment, but is not limited thereto, and may be, for example, the thumb, middle finger, ring finger, and little finger. .

  The actuator 6A is responsible for the rotation of the first link part 3 in the present embodiment, but is not limited thereto, and may be responsible for the rotation of the second link part 4. Also in this case, similarly, the second link portion 4 can be reliably rotated, and the finger joint driving device 1 can be reduced in size and thickness.

  The first base part (first member) 2, the first link part (second member) 3, the second link part (third member) 4, the second base part (fourth member) 5, The first mounting band 20A and the second mounting band 20B correspond to the “mounting mechanism” of the present invention. The second base portion 5 corresponds to the “auxiliary portion” of the present invention, the second mounting band 20B corresponds to the “clamping portion” of the present invention, and the second base portion 5 and the second mounting band 20B are the main. It corresponds to the “auxiliary unit” of the invention.

  FIG. 6 is a flowchart illustrating a control process according to the outputs of the plurality of first force sensors S1 and one second force sensor S2 executed by the control unit 10. This control flow is repeatedly executed until the power is turned off after the power of the finger joint driving device 1 is activated.

  First, in step S102, the output values of the plurality of first force sensors S1 and one second force sensor S2 are acquired, and in step S104, it is determined whether or not the wearer is willing to move. Specifically, the wearer determines whether the absolute value | S2−ΣS1 | of the difference between the sum of the outputs of the plurality of first force sensors S1 and the output of the second force sensor S2 is equal to or greater than the motion determination threshold Ta. The presence / absence of intention to move is determined. Note that the value of the motion determination threshold Ta is set by experimental confirmation in advance in consideration of preventing malfunction and determining the wearer's motion intention. Then, as will be described below, when it is determined that there is an action intention, the processing of step S106 to step S122 is executed, and when it is determined that there is no action intention, the processing of step S130 is executed. The first force sensor S1 and the second force sensor S2 are actually related to the pressure applied from the wearing band at the time of wearing, but here, these pressures are calibrated and output is performed. It is assumed that it is “0”.

  If it is determined in step S104 that there is a motion intention, then in step S106, the motion direction intended by the wearer is determined. Specifically, whether or not the difference (S2−ΣS1) between the output of the second force sensor S2 and the sum of the outputs of the plurality of first force sensors S1 is greater than “0”, that is, the second force sensor S2 The operation direction intended by the wearer is determined based on whether or not the output is larger than the sum (ΣS1) of the outputs of the plurality of first force sensors. As will be described below, when the output difference (S2−ΣS1) is larger than “0”, the operation direction is determined to be the direction in which the hand is gripped (the direction in which the finger is bent), and the processes in steps S110 to S112 are performed. When the output difference (S2-ΣS1) is equal to or less than “0”, it is determined that the movement direction is the direction in which the hand is opened (the direction in which the finger is extended), and the processing in steps S120 to S122 is executed.

  When it is determined that the movement direction is the direction in which the hand is gripped, in step S110, the movement speed (grasping movement speed) or movement distance (grabbing movement distance) for grasping the hand is determined according to the output difference | S2-ΣS1 |. Then, in step S112, the actuator 6A is instructed to hold the hand at the operating speed or operating distance determined (the grasping operation), and the actuator 6A is based on the instructed operating speed or operating distance. Rotate.

  On the other hand, when it is determined that the movement direction is the direction to open the hand, in step S120, the movement speed (release movement speed) or movement distance for opening the hand is determined according to the output difference | S1-ΣS2 |. In step S122, as in step S112, the actuator 6A is instructed to open the hand (release operation) at the determined operating speed or operating distance, and the actuator 6A is based on the instructed operating speed or operating distance. The first link portion 3 is rotated.

  If it is determined in step S104 that there is no intention to operate, in step S130, the actuator 6A is instructed to maintain the immediately preceding state with the operation speed or the operation distance being “0” (state maintenance). The actuator 6A operates to maintain the instructed state. For example, when the hand 100 is gripping an object, the actuator 6A operates to maintain the driving state of the first link unit 3 at that time. Further, in a free state where the hand 100 is not holding anything, the actuator 6A stops its operation while maintaining the position of the first link portion 3 at that time.

  As described above, in the finger joint driving device 1 of the present embodiment, the output values of the plurality of first force sensors S1 and the output values of one second force sensor are acquired, and the operation based on the acquired output values The movement state of the finger can be detected with high accuracy by determination of will (whether or not willing to move the hand) and determination of movement direction (holding [holding] / opening [release]). Then, according to this result, the first link portion 3 can be driven by the actuator 6A. Thereby, the operation of the hand 100 wearing the finger joint driving device 1, more specifically, the index finger 101 can be assisted. In particular, in the finger joint driving device 1 of the present embodiment, a plurality of first force sensors S1 are disposed along the longitudinal direction of the index finger 101 on the back surface 51 of the middle joint 103 of the second base portion 5. (See FIG. 2) As described below, the force generated between the second base portion 5 and the middle segment 103 of the index finger 101 is detected with high accuracy to determine the wearer's movement intention and the movement direction. Can be determined with high accuracy, and the movement state of the finger can be detected with high accuracy.

  FIG. 7 is an explanatory diagram showing the effect of disposing a plurality of first force sensors S1. FIGS. 7A and 7B show, as a comparative example, a case in which a hand is opened in a direction in which a hand is opened (a direction in which a finger is stretched) and a direction in which a hand is gripped (a finger is bent) in a state where one first force sensor S1 is provided. 1R schematically shows a finger joint drive device 1R in the case of being operated in the direction). FIG. 7C schematically shows the finger joint driving device 1 in the case where the operation is performed in the direction in which the hand of FIG. 7A is opened (direction in which the finger is extended) in the present embodiment.

  In the case of the comparative example in which one first force sensor S1 is disposed opposite to the second force sensor S2 with the middle section 103 of the index finger 101 interposed therebetween, as shown in FIGS. 7A and 7B, the wearer holds the index finger. When bent and stretched, a deviation may occur in a portion where the second base portion 5 and the back side of the index finger 101 (particularly the middle joint 103) are in contact. When the index finger 101 (particularly the middle joint 103) contacts the part other than the first force sensor S1, for example, the base part 5, the load applied to the first force sensor S1 is diffused. This is reduced compared to the case where the index finger 101 touches only S1. For this reason, in particular, it becomes difficult to accurately detect the force that is applied when the wearer tries to open the hand (the force that is applied when the finger is extended). Therefore, it is difficult for one first force sensor S1 to detect the force generated between the second base portion 5 and the middle joint 103 of the index finger 101 with high accuracy in accordance with the wearer's intention to operate. Further, since the force sensor (contact force sensor) used for the first force sensor S1 detects a force applied in one axial direction (direction perpendicular to the sensor surface), FIG. When a bias occurs as shown in B), a moment component accompanying bending and stretching of the finger is added to the detected output value, and it is difficult to detect with high accuracy.

  On the other hand, in the present embodiment, as shown in FIG. 7C, a plurality of first force sensors S1 are arranged along the longitudinal direction of the index finger 101, so that a plurality of first force sensors S1. It is possible to detect a different force distribution for each position where the is disposed. This makes it possible to accurately detect the force that is applied when the wearer tries to open the hand (the force that is applied when the finger is extended). In addition, the second force sensor S2 can also detect a force that acts when the wearer tries to hold a hand (force that tries to bend a finger). As a result, for example, as described in the control flow of FIG. 6, the sum of the outputs (ΣS1) of the plurality of first force sensors S1 and the output of one second force sensor S2 are determined as an action intention or an action direction. Therefore, it is possible to perform the determination of the action intention and the determination of the operation direction with high accuracy.

  In the above embodiment, the case where the two first force sensors S1 are arranged along the longitudinal direction of the index finger 101 is described as an example. However, the present invention is not limited to this. The force sensor S1 may be arranged along the longitudinal direction of the index finger 101. Moreover, you may make it arrange | position several 1st force sensor S1 not only in a longitudinal direction but along the width direction. By arranging a plurality of sensors in this way, it is possible to detect the distribution of the generated force more accurately, and the force that the wearer tries to open the hand (the force that tries to stretch the finger) It is possible to detect with higher accuracy, to determine the intention of movement and the direction of movement with higher accuracy, and to detect the movement state of the finger with higher accuracy.

B. Second embodiment:
FIG. 8 is a cross-sectional view of the finger joint drive device 1B of the second embodiment. FIG. 8 corresponds to a cross-sectional view taken along line AA of the finger joint drive device 1 of the first embodiment shown in FIG. As shown in FIG. 8, the finger joint driving device 1 </ b> B of the present embodiment has a plurality (two in the example of FIG. 8) of second force sensors S <b> 2 arranged on the second wearing band 20 </ b> B along the longitudinal direction of the index finger 101. This is different from the driving device 1 (see FIG. 2) of the first embodiment. Further, along with this structural difference, as will be described below, the operation intention determination process and the operation direction determination process in the control process executed by the control unit 10 are different.

  FIG. 9 is a flowchart illustrating control processing according to outputs of the plurality of first force sensors S1 and the plurality of second force sensors S2 executed by the control unit 10. This control flow is repeatedly executed until the power is turned off after the power of the finger joint drive device 1B is activated. This control flow is obtained by replacing steps S102 to S106 of the control flow of the first embodiment shown in FIG. 6 with steps S102B to S106B, and the other processes of other steps S110 to S130 are the same.

  In step S102B, the output values of the plurality of first force sensors S1 and the plurality of second force sensors S2 are acquired, and in step S104B, it is determined whether or not the wearer is willing to move. Specifically, it is mounted depending on whether or not the absolute value | ΣS2−ΣS1 | of the difference between the sum of the outputs of the plurality of first force sensors S1 and the sum of the outputs of the second force sensor S2 is equal to or greater than the operation determination threshold Ta. The presence or absence of the person's willingness to move is determined.

  If it is determined that there is no intention to move, in step S130, the actuator 6A is instructed to maintain the previous state with the operation speed or the operation distance being “0” (state maintenance), and the actuator 6A is instructed. Operate to maintain the state.

  On the other hand, if it is determined that there is a motion intention, then in step S106B, the motion direction intended by the wearer is determined. Specifically, whether or not the difference (ΣS2−ΣS1) between the sum of the outputs of the plurality of second force sensors S2 (ΣS2) and the sum of the outputs of the plurality of first force sensors S1 is greater than “0”, that is, The operation direction intended by the wearer is determined based on whether or not the sum (ΣS2) of the outputs of the plurality of second force sensors S2 is greater than the sum (ΣS1) of the outputs of the plurality of first force sensors.

  If the output difference (ΣS2−ΣS1) is greater than “0”, the movement direction is determined to be the direction in which the hand is gripped (the direction in which the finger is bent), and the hand is gripped in step S110 according to the output difference | ΣS2−ΣS1 | An operation speed (grasping operation speed) or an operation distance (grasping operation distance) is determined. Then, in step S112, the actuator 6A is instructed to hold the hand at the operating speed or operating distance determined (the grasping operation), and the actuator 6A is based on the instructed operating speed or operating distance. Rotate.

  On the other hand, when the output difference (ΣS2−ΣS1) is “0” or less, it is determined that the movement direction is the direction in which the hand is opened (the direction in which the finger is extended), and in step S120, the hand is moved according to the output difference | The operation speed (release operation speed) or operation distance for opening the door is determined. In step S122, as in step S112, the actuator 6A is instructed to open the hand (release operation) at the determined operating speed or operating distance, and the actuator 6A is based on the instructed operating speed or operating distance. The first link portion 3 is rotated.

  Also in the finger joint drive device 1B of the present embodiment, the output values of the plurality of first force sensors S1 and the output values of one second force sensor are acquired, and the movement intention determination based on the acquired output values (hands The first link portion 3 can be driven by the actuator 6A in accordance with the result of the determination of the intention to move) and the result of the movement direction determination (holding [holding] / opening [release]). Thereby, the operation of the hand 100 wearing the finger joint driving device 1B, more specifically, the index finger 101 can be assisted. In particular, in the finger joint drive device 1 </ b> B of the present embodiment, a plurality of first force sensors S <b> 1 are arranged on the back surface 51 of the middle joint 103 of the second base portion 5 along the longitudinal direction of the index finger 101. In addition, a plurality of second force sensors S2 are disposed along the longitudinal direction of the index finger 101 on the ventral surface of the middle joint 103 of the second wearing band 20B (see FIG. 8). As a result, as in the first embodiment, it is possible to accurately detect the force that is applied when the wearer tries to open the hand (the force that is applied when the finger is extended). In addition, a plurality of second force sensors S2 can accurately detect a force that is applied when the wearer tries to hold a hand (a force that is applied when a finger is bent). As a result, for example, as described in the control flow of FIG. 9, the sum of the output values of the plurality of first force sensors S1 (ΣS1) and the sum of the outputs of the plurality of second force sensors S2 (ΣS2) are obtained. By using the determination of the movement intention and the determination of the movement direction, the determination of the movement intention and the movement direction can be performed with high accuracy, and the movement state of the finger can be detected with high accuracy.

  In this embodiment, three or more first force sensors S1 may be arranged along the longitudinal direction of the index finger 101. Moreover, you may make it arrange | position several 1st force sensor S1 not only in a longitudinal direction but along the width direction. Similarly, three or more second force sensors S2 may be arranged along the longitudinal direction of the index finger 101, and a plurality of second force sensors S2 are arranged not only in the longitudinal direction but also in the width direction. May be arranged. By arranging multiple sensors like these, it is possible to detect the distribution of the generated force more accurately, and the force that the wearer tries to open the hand (the force that tries to stretch the finger) It is also possible to detect the force (force to bend the finger) that works when trying to grasp the hand with higher accuracy, and to determine the willingness of movement and the direction of movement with higher accuracy. It is possible to detect the operation state with high accuracy.

C. Third embodiment:
FIG. 10 is a cross-sectional view of the finger joint drive device 1C of the third embodiment. FIG. 10 corresponds to a cross-sectional view taken along line AA of the finger joint drive device 1 of the first embodiment shown in FIG. As shown in FIG. 10, the finger joint drive device 1C of the present embodiment is different from the drive device 1 of the first embodiment (see FIG. 2) in that the second force sensor S2 is omitted. Further, along with this structural difference, as will be described below, the operation intention determination process and the operation direction determination process in the control process executed by the control unit 10 are different.

  FIG. 11 is a flowchart illustrating a control process according to the outputs of the plurality of first force sensors S1 executed by the control unit 10. This control flow is repeatedly executed until the power source is cut off after the power source of the finger joint driving device 1C is activated. This control flow is obtained by replacing steps S102 to S106 of the control flow of the first embodiment shown in FIG. 6 with steps S102C to S106C, and the other steps S110 to S130 are the same.

  In step S102C, the output values of the plurality of first force sensors S1 are acquired. In step S104C, it is determined whether or not the wearer is willing to move. Specifically, the presence / absence of the wearer's movement intention is determined based on whether or not the absolute value | ΣS1 | of the sums of the outputs of the plurality of first force sensors S1 is equal to or greater than the movement determination threshold Ta.

  If it is determined that there is no intention to move, in step S130, the actuator 6A is instructed to maintain the previous state with the operation speed or the operation distance being “0” (state maintenance), and the actuator 6A is instructed. Operate to maintain the state.

  On the other hand, if it is determined that there is a movement intention, the movement direction intended by the wearer is then determined in step S106C. Specifically, the movement direction intended by the wearer is determined based on whether or not the sum (ΣS1) of the outputs of the plurality of first force sensors S1 is smaller than the base value BL. The base value BL indicates the pressurization applied to the entirety of the plurality of first force sensors S1 during mounting.

  When the sum (ΣS1) of the outputs of the plurality of first force sensors S1 is smaller than the base value BL, the operation direction is determined to be the direction in which the hand is gripped (the direction in which the finger is bent), and in step S110, the plurality of first force sensors The operating speed (grasping operating speed) or operating distance (holding operating distance) for grasping the hand is determined according to the sum of outputs S1 | ΣS1 |. Then, in step S112, the actuator 6A is instructed to hold the hand at the operating speed or operating distance determined (the grasping operation), and the actuator 6A is based on the instructed operating speed or operating distance. Rotate.

  On the other hand, when the sum (ΣS1) of the outputs of the plurality of first force sensors S1 is greater than or equal to the base value BL, the movement direction is determined to be the direction in which the hand is opened (the direction in which the finger is extended). The operating speed (release operating speed) or operating distance for opening the hand is determined according to the sum | ΣS1 | of the outputs of the force sensor S1. In step S122, as in step S112, the actuator 6A is instructed to open the hand (release operation) at the determined operating speed or operating distance, and the actuator 6A is based on the instructed operating speed or operating distance. The first link portion 3 is rotated.

  Also in the finger joint drive device 1C of the present embodiment, the output values of the plurality of first force sensors S1 are acquired, and the motion intention determination (presence of intention to move the hand) and the motion direction determination (hand) based on the acquired output values. The first link portion 3 can be driven by the actuator 6A according to the result of [holding / opening [releasing]). Thereby, the operation of the hand 100 wearing the finger joint drive device 1C, more specifically, the index finger 101 can be assisted. In particular, in the finger joint drive device 1 </ b> C of the present embodiment, a plurality of first force sensors S <b> 1 are disposed along the longitudinal direction of the index finger 101 on the back surface 51 of the middle joint 103 of the second base portion 5. (See FIG. 10). As a result, as in the first embodiment, it is possible to accurately detect the force that is applied when the wearer tries to open the hand (the force that is applied when the finger is extended). In addition, although it is disadvantageous compared to the case where the second force sensor is provided, the force that acts when the wearer tries to grasp the hand (the force that works when the finger is bent) is also detected with a certain degree of accuracy. It is possible. As a result, for example, as described in the control flow of FIG. 6, the sum of output values (ΣS1) of the plurality of first force sensors S1 is used for the determination of the operation intention and the determination of the operation direction. The determination and the determination of the movement direction can be performed with high accuracy, and the movement state of the finger can be detected with high accuracy.

  In this embodiment, three or more first force sensors S1 may be arranged along the longitudinal direction of the index finger 101. Moreover, you may make it arrange | position several 1st force sensor S1 not only in a longitudinal direction but along the width direction. By arranging a plurality of sensors in this way, it is possible to detect the distribution of the generated force more accurately, and the force that the wearer tries to open the hand (the force that tries to extend the finger) and It is possible to detect the force (force to bend the finger) when trying to grasp the hand with higher accuracy, and to determine the will of movement and the direction of movement with higher accuracy. It is possible to detect the state with high accuracy.

D. Variation:
The present invention is not limited to the above-described examples and embodiments, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

D1. Modification 1:
As described above, the finger joint drive device has been described as an example of the drive device of the present invention. However, the present invention is not limited to this, and each part constituting the finger joint drive device may be any device that can exhibit the same function. It can be replaced with the configuration of Moreover, arbitrary components may be added. Any two or more configurations (features) of the above embodiments may be combined.

D2. Modification 2:
The actuator 6A can take the rotation of the first link part 3 in the above embodiment, but may take the approach and separation drive of the second base part 5 with respect to the first base part 2. In addition, the actuator 6A has been described by taking a configuration using a piezoelectric driving device as an actuator, but any other actuator can be used. For example, a general small motor or an electromagnetic actuator can be used. It is also possible to use an actuator composed of a wire and a tensioner that changes the tension of the wire, an actuator composed of a hose and a pump that changes the hydraulic pressure and air pressure in the hose, and the like.

D3. Modification 3:
In the above-described embodiment, the drive device (finger joint drive device) that assists the movement of the finger joint of a human hand has been described as an example. However, the present invention is not limited to this, and the human foot finger, elbow, wrist The present invention is also applicable to a driving device that assists the movement of other biological parts such as the knee, neck, and waist. Further, the present invention can also be applied to a driving device that assists the movement of not only a human but also a living body part such as an animal or a non-living body such as a robot.

D4. Modification 4:
In the above embodiment, the sum of outputs of a plurality of force sensors is simply used for determination of movement intention and movement direction, but the moment component due to bending and stretching of the finger is obtained based on the distribution of output values of each sensor, Only the direction component perpendicular to the sensor surface of each sensor may be separated, and only the separated vertical direction component may be used.

  In addition, the reason why the sum of the outputs of the plurality of sensors is used in each of the above-described embodiments is because an example in which a force sensor that detects force is used as the sensor is described. For example, when a pressure sensor that detects force (pressure) per unit area is used as a sensor, an average value of a plurality of sensors is obtained, and an action determination and an action direction are determined based on the obtained pressure. That's fine. Further, it is possible to determine the action intention and the action direction based on the force obtained by multiplying the obtained average value by the pressure receiving area.

  The present invention is not limited to the above-described embodiments, examples, and modifications, and can be realized with various configurations without departing from the spirit thereof. For example, the technical features in the embodiments, examples, and modifications corresponding to the technical features in each embodiment described in the summary section of the invention are to solve some or all of the above-described problems, or In order to achieve part or all of the above-described effects, replacement or combination can be performed as appropriate. Further, if the technical feature is not described as essential in the present specification, it can be deleted as appropriate.

DESCRIPTION OF SYMBOLS 1, 1B, 1C ... Finger joint drive device 2 ... 1st base part (1st member) 21 ... Surface 22 ... Side surface 3 ... 1st link part (2nd member) 31 ... Top plate 32 ... ... side wall 4 ... second link part (third member) 41 ... sliding part 411 ... hollow part 42 ... projecting part 5 ... second base part (fourth member) 51 ... side 52 ... side 53 …… Rail 6A …… Actuator 61 …… First rotor 62 …… Second rotor 63 …… Third rotor 64 …… Piezoelectric drive device 65 …… Vibrating structure 651 …… Piezoelectric element 66 …… Vibrating plate 67 ...... Protrusions 68 ...... Supporting parts 69 ...... Connecting plate 10 ...... Control parts 11, 12 ...... Rotating support parts 20 </ b> A, 20 </ b> B. … Basic clause 103 …… middle clause 104 …… end paragraph 105 …… hand 106 ...... palm 107 ...... proximal interphalangeal joints (second joint) 108 ...... metacarpophalangeal joints (third joint) 109 ...... distal interphalangeal joint (first joint) _{O 11, O 12,} O ₁₀₇ ...... Rotating shaft

Claims (8)

A mounting mechanism mounted on a mounted portion having a first portion and a second portion that are relatively rotated by a joint, and a first base portion corresponding to the first portion and a second portion corresponding to the second portion. A mounting mechanism having two base parts ;
An actuator for driving the second base portion relative to the first base portion ;
A plurality of first force sensors disposed between the second base portion and the second portion along a direction perpendicular to the rotation axis of the joint ;
Equipped with a,
The actuator is mounted on the basis of a direction of movement of the mounted portion according to a sum of a plurality of first detection values obtained from the plurality of first force sensors that change according to movement of the mounted portion. driving apparatus characterized by driving the mechanism. The drive device according to claim 1,
A driving apparatus comprising: at least one second force sensor arranged to face the plurality of first force sensors with the second portion interposed therebetween. The drive device according to claim 2 ,
The actuator is pre-Symbol said mating attachment in accordance with at least one second detection value obtained from the sum and the at least one second force sensors of the plurality of first detection value changes according to the movement of the mounting portion A drive device that drives the mounting mechanism based on the direction of movement of the part . The drive device according to claim 2 or 3 , wherein
A driving apparatus comprising: the plurality of second force sensors arranged to face the plurality of first force sensors with the second part interposed therebetween. It is a drive device as described in any one of Claim 1- Claim 4 , Comprising:
A drive device comprising: a pressure receiving plate disposed between the plurality of first force sensors and the second portion so as to contact the plurality of first force sensors. It is a drive device as described in any one of Claim 1- Claim 5 , Comprising:
The attached portion is a finger,
The plurality of first force sensor driving apparatus characterized by being arranged along the longitudinal direction of at least the finger at the dorsal side of the finger. It is a drive device as described in any one of Claim 1- Claim 6 , Comprising:
The actuator includes a piezoelectric driving device that generates a driving force for driving the mounting mechanism,
The piezoelectric drive device
A diaphragm having a first surface and a second surface; and a vibrating body disposed on at least one of the first surface and the second surface of the diaphragm,
The vibrating body includes a piezoelectric body, and a first electrode and a second electrode that sandwich the piezoelectric body.
A drive device characterized by that. A driving method for a driving device, comprising:
The driving device includes:
A mounting mechanism mounted on a mounted portion having a first portion and a second portion that are relatively rotated by a joint, and a first base portion corresponding to the first portion and a second portion corresponding to the second portion. A mounting mechanism having two base parts ;
An actuator for driving the second base portion relative to the first base portion ;
A plurality of first force sensors disposed between the second base portion and the second portion along a direction perpendicular to the rotation axis of the joint ;
With
Driving the actuator based on a direction of movement of the mounted portion according to a sum of a plurality of first detection values obtained from the plurality of first force sensors that change according to the movement of the mounted portion. And driving the mounting mechanism.

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