JPH0938878A - Manipulator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manipulator by which a controlled member can move in a free space accurately. SOLUTION: Three muscles 7a-7c consisting of a bendable linear member are fixed and arranged respectively through a guide hole between three slide screw nuts of a drive part 5 arranged in the back side of the standard surface 3 of a guide plate 4 and a tip end part 2. The screw shaft 11 screwed to a slide screw nut is rotated and driven in normal/reverse both directions through a gear part by motors 10a-10c and extends or contracts the muscles 7a-7c between the standard surface 3 and a tip end part 2 through the slide screw nut. In CPU in a control circuit, the rotation of the motors 10a-10c is controlled by converting the moving amount of the tip end part to control to the individual moving amount (advance/retreat amount) of three muscles 7a-7c from the present position data and the moved position data of the muscles 7a-7c.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a manipulator for driving a mascule forward and backward with a screw shaft to move a controlled member in space.

[0002]

2. Description of the Related Art Conventionally, there is a manipulator as a device that controls a controlled member such as a pseudo fingertip by a control device and causes the controlled member to move in space (spatial motion).
For controlling (driving) such a manipulator, one using two wires, one using air pressure, one using thermal expansion of a liquid, etc. are known.

In the case of using two wires, each end of the wire for moving the controlled member in the x direction and the wire for moving the controlled member in the y direction is wound around a pulley with a dial.
For control, the dials are manually turned as appropriate to pull or push the wire wound around the pulley to change the angle of the controlled member.

In the case of using air pressure, the piston of the air cylinder is advanced and retracted to rotate the controlled member in one direction. Alternatively, a plurality of air cylinders and moving arms can be combined to allow the control member to perform complicated spatial movement.

Further, in the case of using the thermal expansion of a liquid, the liquid enclosed in an extremely small housing is expanded by the heat generated by a heating element and introduced into the cylinder, and the piston of the cylinder is driven by the pressure. There is.

[0006]

However, the one using the above-mentioned two wires has a drawback that the precision of the moving position of the controlled member cannot be obtained because the pulley is manually rotated. Also, the one using air pressure is
Since a compressor that supplies compressed air to the air cylinder is required, the device becomes large and there is a problem in using it for a small manipulator. Further, the one using the thermal expansion of the liquid requires efficient heat conduction in order to obtain a quick operation, which makes the individual units extremely small,
Since the amount of displacement obtained is small, a multi-stage configuration is often used to obtain a large amount of displacement, so that not only the cost of the apparatus as a whole increases but also control is complicated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described conventional circumstances,
It is an object of the present invention to provide a manipulator that controls a controlled member with a driving source to accurately perform an operation of bending the controlled member at a free angle like a finger to move in a free space.

[0008]

The structure of the manipulator of the present invention will be described below. The manipulator of the present invention is
Three masles, which are made of linear members having flexible elasticity and are arranged so as to form a ridge of a triangular prism, a controlled member to which one end of each of the masles is fixed, and a counter electrode of the controlled member. A guide plate which has a guide hole and which has a reference surface facing the controlled member and which respectively inserts the three masles.
Drive means arranged on the back side of the reference surface of the guide plate for moving at least one of the masles forward and backward from the reference surface to the controlled member side through the guide hole, and controlling the drive operation of the drive means. And a driving means,
A power source, a screw shaft rotatably in both forward and reverse directions by the power source and arranged in parallel with the advancing / retreating direction of the massle, and one of the screw shafts is screwed to the other, and the other end of the massle is fixed to the other. And a screw nut member that moves back and forth on the screw shaft in response to both forward and reverse rotations of the screw shaft.

The driving means is arranged for each masle, for example, and drives the masle via the screw nut member by rotating the screw shaft in either forward or reverse directions. As a result, the masle advances or retracts from the guide hole to move the controlled member to a desired position in all directions within the longest bending range of the masle with respect to the reference plane.

Further, as described in claim 3, for example, at least one position display means disposed on the drive rotation shaft of the power source, and a slave of the position display means according to the rotation of the drive rotation shaft. Further having a rotation sensor for detecting rotation,
The control means controls the amount of advance / retreat of the masle by controlling the rotation of the screw shaft by the drive means based on the detection output of the rotation sensor to control the moving position of the controlled member.

Further, the control means is, for example, as described in claim 4, position data composed of x-coordinates, y-coordinates and z-coordinates representing a spatial position of the controlled member with respect to the reference plane, or a bending angle and a bending direction. And position data consisting of height and finger speed data representing the moving speed of the controlled member, and the massle position data of the massle corresponding to the moving destination of the controlled member from the position data and the finger speed data. And, the massle moving speed data is generated, and the controlled member is spatially moved based on the massle position data and the massle moving speed data. Further, for example, claim 5
As described above, it has a storage unit for storing the current position data of the masle, and updates the current position data stored in the storage unit every time the movement of the controlled member is controlled, The control rotation speed of the power source for controlling the advance / retreat of the massle from the current position to the movement destination position is generated based on the massle position data, and the drive operation of the drive means is controlled based on the generated control rotation speed. . Also,
For example, as described in claim 6, a position sensor is further provided which is capable of detecting the position of the masle at least at one portion, and the position of the masle detected by the position sensor is used as absolute position data with respect to the reference plane. The movement of the controlled member is controlled via the drive means while holding and correcting the massle position data based on the absolute position data of the massle. Further, for example, as described in claim 7, when the position sensor detects the maslu while controlling the forward / backward movement of the maslu, the absolute position data of the maslu is updated. Further, for example, as described in claim 8, when a predetermined period of time elapses during the control of the forward / backward movement of the maslu, the position sensor is forcibly detected to detect the absolute position data of the maslu. Update. Further, as described in claim 9, for example, the massle movement amount limitation data preset corresponding to the allowable movement range of the controlled member is held, and the movement-set massle position data and the massle movement amount limitation are set. When the massle position data exceeds the massle movement amount limit data by comparing with the data, error control is performed without performing the movement control based on the movement setting, and the control is returned to the initial value.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing the structure of a finger (Finger: manipulator) of the first embodiment, FIG. 2 is a bottom sectional view thereof, and FIG. 3 is a unit structure of a muscle thereof. It is a perspective view shown.

As shown in FIGS. 1 to 3, the finger 1 is
A finger tip portion 2 which is a controlled member (see FIG. 1), and a guide plate 4 which is positioned opposite to the finger tip portion 2 with the reference plane 3 facing the finger tip portion 2 (see FIGS. 1 and 3).
(See FIG. 1), and the finger tip portion 2 formed of a wire-like or coil-spring-like linear member having bendable elasticity and a drive portion 5 disposed on the back side of the reference surface 3 of the guide plate 4. And three reference points 3 of the guide plate 4, three masles 7 (7a, 7a) arranged to form a ridge of a triangular prism.
b, 7c). For these masles 7, members having the same elastic coefficient and the same shape are used.

The drive unit 5 includes a case 8 having a bottomed cylindrical shape (see FIG. 1), and an upper opening (right side in FIG. 1) of the case 8 is covered with the guide plate 4. . The case 8 is provided with a bearing plate 9 arranged in the vicinity of the bottom and parallel to the bottom. Between the bearing plate 9 and the guide plate 4, three motors 10 (10a, 10a, 10
b, 10c) are arranged parallel to the axis and form a triangular prism as a whole.

Three screw shafts 11 (11a, 11b, 11c) are arranged between the motors 10 in parallel with the rotation axis of the motors 10. The screw shaft 11 is
One end is pivotally supported by the guide plate 4 and the other end is pivotally supported by the bearing plate 9, and at the end pivotally supported by the bearing plate 9, the fourth gear of the gear portion 12 (12a, 12b, 12c) is provided. 12-
4 (12a-4, 12b-4, 12c-4) are fixed.

Gear portion 12 (12a, 12b, 12c)
Is the housing 1 of the motor 10 at the bottom of the case 8.
3 (13a, 13b, 13c) and the bearing plate 9 support the first gear 12-1 (12a-1, 12b-1,
12c-1), the second gear 12-2 (12a-2, 12b)
-2, 12c-2) and the third gear 12-3 (12a-
3, 12b-3, 12c-3) and the fourth gear 1 described above.
2-4 (12a-4, 12b-4, 12c-4).

The first gear 12-1 is fixed to the rotary shaft of the motor 10, and the second gear 12-2 and the third gear 12-3 are idle gears coaxially coupled to each other. The rotation of the motor 10 in both the forward and reverse directions is determined by the first gear 12-1 and the second gear.
Gear 12-2, third gear 12-3 and fourth gear 12-4
Is transmitted to the screw shaft 11 via. As a result, the screw shaft 11 is rotationally driven in both forward and reverse directions.

A slide screw nut 14 (14a, 14b, 14c) is screwed onto the screw shaft 11, and moves forward and backward on the screw shaft 11 in response to both the forward and reverse rotations of the screw shaft 11 described above. (To the left and right as seen in FIGS. 1 and 3, toward the front or the other side as seen in FIG. 2)
Moving.

One end of the above-mentioned masuru 7 is fixed to the finger tip portion 2 and the other end thereof penetrates a guide hole 6 formed in the guide plate 4 and is locked to the slide screw nut 14. As the slide screw nut 14 moves forward and backward in response to either forward or reverse rotation of the screw shaft 10, the end portion of the mastle 7 locked to the slide screw nut 14 is pulled or pushed out. As a result, the mastle 7 between the finger tip portion 2 and the reference surface 3 of the guide plate 4 advances or retracts from the guide hole 6. As the masle 7 advances or retracts, the finger tip portion 2 moves (finger operation) in all directions within the longest bending range of the masle 7 with respect to the reference surface 4.

In the configuration of this embodiment, as shown in the figure,
The muscle 7 is arranged so as to be longer than the length of the screw shaft 11. As a result, the mascule 7 can be slid in parallel with the screw shaft 11 to expand and contract the effective portion between the reference surface and the finger tips, and therefore, the space for disposing the mascule 7 and the drive mechanism is not wasted. Therefore, the device can be downsized.

Further, the screw shaft 11 is a motor 10
It is configured to be parallel to the rotation axis of. As a result, the overall size (volume) can be reduced, and
The sliding amount (axial length of the screw shaft 11) can be increased.

Further, in the case 8, the sliding portion of the mastle 7 which moves forward and backward by being locked by the slide screw nut 14, the screw shaft 11, the inner wall of the case 8 and the outer wall of the two motors 10 adjacent to each other. It is configured so as to be disposed in the gap formed by. As a result, it is possible to dispose the massles 7 so that the distance between the massles 7 is maximized in a narrow space. Therefore, it is possible to configure a finger having a large operating range despite its small size.

The slide screw nut 14 is formed into a shape that is in partial sliding contact with the outer wall of the housing 13 of the motor 10 or the inner wall of the case 8.
Is configured so as not to rotate together with the screw shaft 11. As a result, the slide screw nut 14 comes to slide properly on the screw shaft 11 according to the rotation of the screw shaft 11.

Further, in the structure of the finger 1 shown in FIGS. 1 to 3, the guide plate 6 is provided with the bearing portion for pivotally supporting the guide hole 6 and the screw shaft 11 for positioning the arrangement of the maslu 7 as described above. There is. Thus, since the guide plate 4 also serves as the other bearing plate facing the one bearing plate 9 of the screw shaft 11, the number of members used is reduced, the structure is simplified, and the overall size can be reduced.

As described above, the finger 1 is constructed by arranging three massle units shown in FIG. 3 as shown in FIG. FIG. 4 (a) is a diagram showing an operation state of vertical movement of the finger 1, that is, the finger tip portion 2, and FIG.
FIG. 6 is a diagram showing an operating state of rotational movement of the finger tip portion 2. In the configuration of this embodiment described above, by independently controlling the drive of the motors 10 corresponding to the respective masles 7, as shown in FIGS. (Length between the part 2 and the reference surface 3 of the guide plate 4)
Expands and contracts, whereby the finger tip 2 can be operated (finger operation) at a free position in the space.

Next, the relationship between the length of each of the masles 7a, 7b and 7c and the operating position of the finger tip 2 corresponding to these lengths will be described. FIG. 5 (a) is a layout coordinate diagram of the masuru 7, FIG. 5 (b) is a coordinate development diagram of the finger 1, and FIG. 5 (c) is a diagram showing the shape of the finger tip portion 2. . As shown in (a) of the same figure, on the reference surface 3 of the guide plate 4, the positions of the masles 7a, 7b and 7c (the positions of the guide holes 6a, 6b and 6c) are the vertices of an equilateral triangle. The center of gravity of the triangle is taken as the origin of the three-dimensional coordinates by the x, y, and z axes. Then, the reference plane 3 is set to "z = 0", the arrangement diameter of the masles 7a, 7b and 7c (the diameter of the circumscribed circle of the equilateral triangle formed by the arrangement positions of the respective masles 7) is set to MR, and the arrangement position of the masles 7a is set. Place on the x-axis.

Also, as shown in FIG.
Is the length (the length from the position of the guide hole 6a of the masuru 7a to the fixing position M1 to the finger tip 2) is LM1, and the length of the masuru 7b (the fixation from the guide hole 6b of the masuru 7b to the finger tip 2). Length up to position M2) LM2, Masle 7
The length of c (the length from the guide hole 6c of the masuru 7c to the fixed position M3 to the finger tip 2) is LM3, and the finger tip 2 from the center of gravity of the arrangement position of the masuru 7 (origin of the three-dimensional coordinate). To the center of gravity M of the fixed positions LM1, LM2, and LM3 of each masle 7 to the central virtual masle (center axis of the finger 1) LMc, and the reference plane 3 (" z = 0 ") and the bending angle is θ M,
The angle in the bending direction of the finger tip 2 with respect to the x-axis is αM
, IM is the radius of curvature of the middle virtual masle when the finger tip 2 is bent. Further, as shown in FIG. 3C, the height of the cylindrical portion of the finger tip portion 2 is Ht and the radius of the hemispherical portion is Hr, and the height of the finger tip portion 2 is Hh.
(Hh = Ht + Hr). Then, the position of the central apex of the finger tip portion 2 is set to Ft.

When set as described above, the bending angle θ M of the finger tip portion 2 is

[0029]

[Equation 1]

Then, the polar radius IM of the central virtual masle
Is

[0031]

[Equation 2]

The angle α M in the bending direction of the finger tip 2 is

[0033]

(Equation 3)

## EQU1 ## Therefore, from these equations, the coordinates M (Mx, My) of the center point of the bottom surface of the finger tip portion 2 (the center of gravity M of the fixed positions LM1, LM2, and LM3 of each masuru 7 to the finger tip portion 2) in the above three-dimensional coordinate system. , Mz) is

[0035]

(Equation 4)

[0036]

(Equation 5)

[0037]

(Equation 6)

It can be obtained by In this case, LMc = (LM1 + LM2 + LM3) · 1/3. When LM1 = LM2 = LM3 (= LMc), θM = αM = IM = 0, Mx = My = 0, Mz = LMc.

By calculating using the above relational expressions, three massles 7a, 7b in the three-dimensional coordinate system are calculated.
And the lengths LM1, LM2, and LM3 of 7c are appropriately controlled, and the bending angle θM (Equation 1) of the finger tip portion 2, the angle αM (Equation 2) in the bending direction, and the height M from the reference plane are set.
z (Equation 6) can be arbitrarily determined. That is, the position of the finger 1 (the position of the center point M on the bottom surface of the finger tip 2)
Can be arbitrarily determined as coordinates M (θM, αM, Mz). Also, it can be arbitrarily determined by the above-mentioned coordinates M (Mx, My, Mz) (Equation 4, Equation 5 and Equation 6). That is, the operation of the finger tip portion 2 can be controlled to an arbitrary position in the free space of 360 degrees.

Further, on the basis of the control for the bottom face center point M of the finger tip portion 2 described above, the position of the apex Ft of the finger tip portion 2 or any position on the finger tip portion 2 can be controlled. This uses the coefficients ftx, fty, and ftz based on the shape of the finger tip 2 to coordinate data M (Mx, My, M) of the bottom center point.
This is possible by correcting z). That is, if the vertex coordinates of the finger tip portion 2 are Ft (Ftx, Fty, Ftz), the position of the vertex Ft can be controlled by Ftx = Mx + ftx Fty = My + fty Ftz = Mz + ftz. These coefficients ftx, fty and ftz are coefficients determined by the shape and size of the finger tip portion 2 and the bending angle θM and the bending direction angle αM described above. For example,
In the finger tip portion 2 having the shape “Hh = Ht + Hr” shown in FIG. 5 (c), the above correction coefficient is determined by ftx = Hh.Sin.theta.M.Cos.alpha.fty = Hh.Sin.theta.M.Sin.alpha.ftz = Hh.Cos.theta.M. To be done.

Next, FIG. 6 is an explanatory view in the case where the finger tip portion 2 (that is, the bottom center point M) is circularly moved. FIG. 6 (a) corresponds to the circular movement of the finger tip. The change diagram of the length of each controlled masle, Figure (b), is the circular orbit diagram of the finger tip.

In FIG. 6A, for example, at a height of 40 mm (millimeter), that is, in the plane of Mz = 40 in FIG. 5B, as shown in FIG. The center point M (Mx, My, M) is drawn by drawing r = 10 in FIG.
z) is caused to perform a circular motion (bending direction angle α M is changed from “0” to “2π” with respect to the x-axis),
Displacement of the bending direction angle α M 0 → π / 2 → π → 3π / 2
→ Controlled length LM1, L of each masle 7 corresponding to 2π
The amount of displacement of M2 and LM3 is shown. As shown in FIG. 6 (a), the length of each masle 7 is from a position slightly lower (shorter) than the height (length) 40 mm to a position slightly lower (shorter) than the height (length) 45 mm. Is the displacement range,
It changes with drawing a gentle sine curve (or cosine curve) with a delay of about 120 degrees. In this way, the length of each masle 7 is set to the screw shaft 11 shown in FIGS.
By controlling the rotation of (11a, 11b, 11c), the finger tip portion 2 can be caused to perform the above circular movement. Controlling the length of each masle 7 is
It can be executed using the above-described equations (1) to (6) corresponding to the settings of Mz = 40, r = 10, and α M = 0 to 2π.

In addition, in FIG.
The shortest displacement amount of is even lower than the minimum height of the circular orbit set at 40 mm.
The fixed point M1 (or M2, M3) of (b, 7c) is near the periphery of the bottom surface of the finger tip portion 2, that is, it is always outside the center point M of the bottom surface, as is apparent from FIG. 5 (b). On the bottom surface of the finger tip 2 that is inclined in the bending direction by the circular motion, the fixed point M1 (or M2, M3) of the maslu 7a (or 7b, 7c) coming in the bending direction is This is because it is located below the circular orbital plane (plane with Mz = 0).

In FIG. 6 (a) described above, the larger the amplitude of the sine curve (or cosine curve), the larger the circle drawn by the tip 2 of the finger, and conversely, the smaller the amplitude of the curve, the circle drawn by the tip 2 of the finger. Becomes smaller. Also,
It can be easily understood that the higher the valley of the curve, the farther the finger tip 2 is from the reference plane, and conversely, the lower the valley of the curve, the closer the finger tip 2 is to the reference plane. Also from this, it can be easily known that the finger tips 2 can be moved to arbitrary positions in the free space by controlling the lengths of the three maslu 7.

Next, a method of setting the maximum length LMmax and the minimum length LMmin of the masuru 7 in the control of the moving position of the finger tip portion 2 (that is, the control of the finger 1) will be described. The purpose of this setting is that the bending motion of the finger 1 is 3
Since it is controlled by the book massle 7, the maximum bendable angle is different depending on the bending direction of the finger 1 as will be described later. Therefore, the finger 1 operates uniformly in all directions in the free space. Inconvenience will occur in the control of the power finger 1, and in order to prevent this inconvenience, the maximum value of the bending angle is set in advance so that it can take the same value in all directions. Especially.

FIGS. 7 (a) and 7 (b) are views showing that the maximum bendable angle differs depending on the bending direction of the finger 1. As shown in FIG. Both (a) and (b) of FIG.
Of the driven portion (controlled portion) of the guide plate 4 from the direction perpendicular to the bending direction, that is, the bent state from the side is shown above, and the plan view of the guide plate 4 at that time (masle 7 The layout diagram) is shown below. 5 (a) and 5 (b), the finger tip portion 2 shows the fixed points M1, M2, and M3 of each masle 7 shown in FIG. 5 (b). Also,
Black dots M01, M02, and M03 in the plan view shown below represent the respective masles 7 (7a, 7a) on the reference plane 3 of the guide plate 4, respectively.
b, 7c) (the same as the guide holes 6a, 6b, 6c). And these arrangement positions M01, M
A circle 21 circumscribing 02 and M03 is a circle having a massle arrangement diameter MR shown in FIG. 5 (a). A circle 21 'similar to this,
Fixing points M1, M of each masle 7 at the finger tip 2
It can be assumed as a circumscribed circle 21 'of 2 and M3 (the circumscribed circle 21' cannot be seen in the figure because it is seen from the side).

By the way, as described above, the bending control of the finger 1 is performed by advancing or retracting the masles 7 (see FIG. 6 (a)), but the length of each masle 7 from the reference plane 3 by this control is The maximum advancing amount which is the maximum length and the maximum retracting amount which is the minimum length are automatically determined by the length of the screw shaft 11 shown in FIGS.

Now, for the sake of convenience of description, when the attention is paid to the mascule 7b while ignoring other conditions, as shown by an arrow A in FIG. 7 (a), the finger 1 is maximized in the arrangement position direction of the mascule 7b. When the length LM2 of the maslu 7b is retracted to the minimum length so as to be bent to the limit, the height of the fixed point M2 of the maslu 7b at the bent finger tip portion 2 to the maximum extent from the reference plane 3 is "h". Let's say. This is because the circumscribed circle 21 in which the tip 2 of the finger is inclined in this state is described above.
It is shown that the shortest distance between'and the reference plane 3 is "h". And this is the bending limit in this case.

On the other hand, as shown in FIG. 6B, the direction of bending is changed so that the finger 1 is moved in the middle direction between the maslu 7b and the maslu 7c (the direction of the opposite pole M011 to the maslu 7a on the circumscribing circle 21). If the length LM2 of the maslu b and the length LM3 of the maslu 7c are retracted to the minimum length in order to bend to the maximum extent, the fixed point M2 of the maslu 7b (same as the fixed point M3 of the maslu 7c) from the reference plane 3 You can see that the height is "h". At this time, the circumscribed circle 21 'and the reference plane 3
The shortest point between and is the fixed point M2 (or Masul 7
The circumscribed circle 2 on the above-mentioned reference plane 3 rather than the solid base point M3 of c
A circumscribing circle 21 corresponding to the counter pole point M011 with the maslu 7a of No. 1
It is a virtual point M11 on ‘. This is because the circumscribing circle 21 'is in the middle direction between the maslu 7b and the maslu 7c, that is, the imaginary point M11.
This is because it is inclined in the direction. The distance hi between the virtual point M11 and the reference plane 3 is smaller than the distance h between the fixed point M2 of the masle 7b (or the fixed bottom point M3 of the masle 7c) and the reference plane 3. That is, the circumscribing circle 21 'on the bottom surface of the finger tip 2 in the case of the curve shown in FIG. 9B is closer to the reference plane 3 than in the case of the curve shown in FIG. Therefore,
The center of the circumscribing circle 21 ', that is, the center point M of the bottom surface of the finger tip portion, is closer to the reference plane 3 in the case of the curve shown in FIG. 9A than in the case of the curve shown in FIG. That is,
In any case, although the control of the retraction of the length LM2 is performed up to the limit set for the mascule 7b, the bending of the finger tip portion 2 is different. In other words, the maximum bending state of the finger tip 2 depends on the angle of the bending direction. In this case, as described above, the control of the finger 1 that should move uniformly in all directions in the free space will be inconvenient.

In order to avoid this inconvenience, in the control of the finger 1, the maximum length LMmax and the minimum length LMmin for controlling the mastle 7 are set as described below. this is,
The limit value of control is determined in advance so that the maximum bending angle can take the same value in all directions.

FIG. 8 is a diagram for explaining a method of setting the maximum length LMmax and the minimum length LMmin for controlling the masle 7,
The figure (a) is a motion coefficient setting diagram of the finger, and the figure (b) is a plan layout diagram of the maslu.

First, the maximum length LMmax for controlling the masle 7
And the minimum length LMmin will be described based on the maximum bending angle of the finger 1 and the height from the reference plane 3 at that time. As shown in the figure (a), the maximum value of the bending angle θM in all directions is θMmax, and the height of the finger 1 at that time (height of the center point of the bottom face of the finger tip) M
Assuming that the value of z is Mzθmax, counter pole points M011 and M11 are assumed on the opposite sides of the masles 7a of the circumscribing circles 21 and 21 ′, respectively, as in the case of FIGS. Assume a virtual massle 7k. And the length of the maslu 7a LM1
When the maximum length of the masle is LMmax, the virtual masle 7k
The masses 7b and 7c are controlled to LM2 = LM3 = LMmin.3 / 4 + LMmax.1 / 4 so that the length LMk of the same becomes the minimum length LMmin of the normal massle 7. Further, when the length LM1 of the maslu 7a is the minimum length LMmin of the maslu, the maslus 7b and 7 are arranged so that the length LMk of the virtual maslu 7k becomes the maximum length LMmax of the normal maslu 7.
c is controlled to LM2 = LM3 = LMmin · 1/4 + LMmax · 3/4. By controlling the length of each masle 7 in this way, the maximum bending angle θMmax takes the same value in all directions.

At this time, the maximum change length of the masle is ΔL
If Mmax, from Fig. 8,

[0054]

(Equation 7)

If the minimum radius of curvature of the virtual masle 7k is Ikmin, then

[0056]

(Equation 8)

It is Further, the height Mzθmax of the finger 1 at the maximum bending angle θMmax is

[0058]

[Equation 9]

And therefore,

[0060]

(Equation 10)

[0061]

[Equation 11]

Therefore, the maximum length LMmax for controlling the masle 7
And the minimum length LMmin can be obtained (set). Next, the maximum length LMmax and the minimum length LMm that should control the masle 7
A method of setting in based on the maximum bending angle of the finger 1 and the lateral distance at that time will be described. In this case as well, the condition is that the maximum value of the bending angle θM in all directions is θMmax. As shown in FIG. 8 (a), if the lateral distance of the finger 1 at the maximum bending angle θMmax (bottom center point M of the tip 2) is aM θmax,

[0063]

(Equation 12)

Is as follows. Therefore,

[0065]

(Equation 13)

[0066]

[Equation 14]

As a result, it is possible to set the maximum length LMmax and the minimum length LMmin for controlling the masle 7 so that the finger 1 has the maximum bending angle θMmax in all directions.

In any case, the maximum length LMmax and the minimum length LMmin are set so that the center point M of the bottom surface of the finger tip 2 is set.
Although the position is determined by the position of, the position of the finger tip 2 at any point is taken as the point of interest, and the above formulas (10) and (11) or (13) and ( It can be determined by using the correction coefficients ftx, fty, and ftz that are determined by the shape of the finger tip portion 2 described above in Equation 14).

By the way, when the bending angle θ M of the finger 1 is set large (θ M> about 45 °), the finger 1 is easily deformed from the normal shape to the abnormal shape. FIG. 9 shows a state in which the finger 1 is deformed by bending.
In the finger 1 shown in the figure, the elastic force of the long masuru 7 loses to the elastic force of the other two short masuru, and the finger 1 escapes from the original position shown by the solid line in the figure to the outside as shown by the broken line 7h in the figure. In this state, the curvature of the long masle 7 will bulge outward. Further, in this state, the same phenomenon occurs when the load to move the finger is large.

If such a deformation of the masle 7 is left as it is, the efficiency of the finger operation is lowered. Therefore, it is necessary to prevent (correct) such deformation of the maslu 7.

FIGS. 10 (a) and 10 (b) are views showing an example of a finger in which the bending deformation of the maslu is corrected. FIG. 3A shows a configuration in which the correction coil spring 22 is arranged so as to be circumscribed on the three masles 7. If formed in this way, the outward bulging of the long mastle 7 that causes deformation can be suppressed by the elastic force of the other short masles 7 via the correction coil spring 22. Thereby, the arrangement distance of each masle 7 can be maintained, and therefore, the deformation of the masles 7 can be prevented.

Further, especially when the load applied to the fingers is large, a short masle may be laterally deformed. That is, a long bulge that bulges outward is transformed into a short bulge to be corrected. In order to prevent these deformations,
As shown in FIG. 2B, a plurality of regulating plates 2 including discs with holes for forcibly determining the positional relationship between the three masles 7
3 are arranged at appropriate intervals. In this case, it is important to dispose mainly in the central part. Such a regulation plate 2
By disposing the 3 as well, the deformation of the maslu 7 can be prevented, and thereby the efficiency of the finger operation by the maslu control can be improved.

Although not shown in particular, the fingers may be covered with an elastic outer case (protective cover), and the outer case may be in contact with the three masles 7. By doing so, the correction member such as the above-mentioned auxiliary coil spring 22 or the regulation plate 23 for correcting the deformation of the masle 7 can be shared with the protective cover.

Next, a control method for controlling and driving the controlled portion of the finger composed of the above-described three maslu and the tip portion of the finger will be described. FIG. 11 is a perspective view of a rotation sensor for controlling the rotation of the motor. As shown in the figure, the rotation sensor 25 (25-1, 25-2) is provided on the rotation shaft 24 of the motor 10 shown in FIGS. A rotary arm (encoder) 25-1 is attached, and rotation of the rotary arm 25-1 that follows the rotation of the rotary shaft 24 of the motor 10 in the rotation direction shown by arrow B in the figure is controlled by the following. The photocoupling element 25-2 having a character shape is configured to be detected by the detection opening. The photocoupler element 25-2 is composed of an LED and a phototransistor.

In this way, each screw shaft 11 (1
1a, 11b, 11c, see FIG. 1 to FIG. 3). The rotation sensor 25 detects the rotation of the motor shaft that drives the rotation.
(25a, 25b, 25c) are provided so that the amount of movement of each masulu 7 can be recognized, thereby improving the control accuracy of the fingers or controlling the moving speed of the fingers. However, the rotation sensor 25 is not always necessary when the motor 10 is a motor capable of controlling the rotation speed of the motor by a motor drive signal, such as a stepping motor. Further, the position display means is not limited to the one described above, and for example, the rotary shaft 24.
A mark may be attached to the periphery of the object with paint or the like, and detection may be performed using a reflective sensor.

FIG. 12 is a block diagram of a control circuit for controlling the operation of the fingers. As shown in the figure, the control circuit includes a program memory 32, a memory I33, a memory II34, and a memory II in the CPU 31 (central processing unit).
An I 35, a motor driver 36, a sensor amplifier 37, and a control input / output terminal 38 are connected to each other.

The program memory 32 stores a program for controlling the operation of the fingers, and the above CPU
The reference numeral 31 reads out a program stored in the program memory 32, and controls each of the above parts based on the read-out program.

The memory I33 is a memory for arithmetic processing, and has preset reference position data, various coefficients,
The intermediate data and the like in the process of calculation are stored. Memory II34
Data indicating the current position of each maslu is stored for each maslu.

Based on the above position data, the CPU 31 uses the motor 10 (10a, 10b, 10c), the screw shaft 11 (11a, 11b, 11c), and the slide screw nut 14 (14a, 14b, 14c). Drive the muscle 7 (7a, 7b, 7c) to move the finger 1
In order to control the movement of the photosensor 25-2, a drive signal is output to the motor driver 36, and the photocoupler 25-2 of the rotation sensor 25 is driven to light via the sensor amplifier 37.

Although not particularly shown, the CPU 31 has a plurality of latches S11, S12, and S13 built therein, and the photocoupler 25- of each rotation sensor 25a, 25b, and 25c.
The encoder detection output from 2 is latched, and the number of revolutions of each motor 10 is recognized based on this latch signal as will be described later, whereby the current position of each masle 7, that is, the current position of the finger 1 is correctly recognized.

Subsequently, the CPU 31 of the control circuit having the above configuration
The processing operation for controlling the finger 1 will be described below. FIG. 13 is a flowchart of a process for controlling fingers by the CPU 31 of the control circuit shown in FIG.
In this process, the current position data based on the reference position data stored in the memory I33 is constantly updated under the control of the finger operation, and the updated current position data is stored in the memory II34. It CPU31
Generates control data for a desired position to be controlled based on the reference position data and the current position data, and controls the position of the finger 1, that is, the position (advancing / retreating amount) of each masuru 7.

As shown in the figure, first, the finger position data FA is converted into masle position data LM (step S).
1). This process is a process of converting the finger position data FA into mascule position data LM by calculation. The above-mentioned finger position data FA is the coordinates of the position of the bottom center point M of the finger tip 2 to be moved by this control, and is the coordinate M (Mx, My, Mz) or the coordinate M (θM, α).
Data represented by M, Mz). The massul position data LM is data indicating the lengths LM1, LM2, and LM3 of the respective massles to be moved (advanced or retracted) at this time, and “LM
(LM1, LM2, LM3) ". The lengths LM1, LM2, and LM3 of each of these masles can be calculated by the equations (1) to (6) described above.

[0083]

(Equation 15)

[0084]

(Equation 16)

[0085]

[Equation 17]

Is obtained as In the above equation, θM
, Α M and IM are also expressed by the equations (1) to (6),

[0087]

(Equation 18)

[0088]

[Equation 19]

[0089]

(Equation 20)

It is Then, the massle position data L
M (LM1, LM2, LM3) is converted into rotation amount data LMT in motor rotation speed units based on the gear ratio (step S2). This processing is obtained in advance based on, for example, the numbers of teeth of the first gear 12-1, the second gear 12-2, the third gear 12-3, and the fourth gear 12-4 shown in FIGS. 1 to 3. Using the gear ratio, based on this gear ratio and the screw pitch of the screw shaft 11, the motor 10 corresponding to the unit of movement of the slide screw nut 14, that is, the unit of movement of the masle 7.
Is a process of calculating the rotation amount data LMT up to the control position in units of the number of rotations. The rotation amount data LMT in units of the number of rotations of the motor is calculated by using the rotation amount data LMT1, LMT2, and LMT3 in units of the number of rotations of each motor 10,
(LMT1, LMT2, LMT3) ".

In the conversion into the rotation amount data LMT1, LMT2, and LMT3 in units of the number of rotations of each motor 10, first, the mastle position data LM (LM1, LM2, LM3) is converted into the number of rotations LMS1, LMS2 of the screw shaft 11, And LMS
Convert to 3. Rotational speed L of these screw shafts 11
MS1, LMS2, and LMS3 have the rotation speed of the screw shaft 11 per unit distance of advance and retreat of the masle 7 as k1, that is, "k1 = (revolution speed of the screw shaft 11) / (distance of advance and retreat of the masle 7)",

[0092]

(Equation 21)

[0093]

(Equation 22)

[0094]

(Equation 23)

It is obtained by Next, the rotation speed LMS (LMS1, LMS2, LMS of the obtained screw shaft 11 is obtained.
Based on 3), rotation amount data LMT (LMT1, LMT2, LMT3) in units of the number of rotations of the motor 10 is obtained. The above gear ratio is k2, that is, "k2 = (number of rotations of the motor 10)"
/ (Number of rotations of screw shaft 11) ", and the above k1
If the product of k2 and k2 is a coefficient k3, that is, "k3 = k1.k2", then LMT1 = k2.LMS1 = k3.LM1 LMT2 = k2.LMS2 = k3.LM2 LMT3 = k2.LMS3 = k3.LM3. As described above, the rotation amount data LMT (L
MT1, LMT2, LMT3) are obtained.

Subsequently, based on the rotation amount data LMT (LMT1, LMT2, LMT3) in the rotation number unit of the motor 10, the rotation number TM of the motor 10 from the current position to the position to be controlled is obtained (step S3). . The data indicating the current position is the rotation amount data AP (“AP (AP1,
AP2, AP3) ”) is stored in the memory II 34. Then, each time the movement control to the position to be controlled is completed, the current position data after the control is rewritten as described later, whereby the current position data AP is constantly updated. Using this current position data AP, the number of revolutions TM (TM1, TM2, TM3) of the motor 10 for moving from the current position to the position to be controlled is: TM1 = LMT1−AP1 TM2 = LMT1−AP2 TM3 = LMT1 -Obtained by AP3.

Next, the speed data of each masle 7 is calculated from the moving speed data Fs of the finger 1 up to this control position (step S4). This is because the amount of advance / retreat of each masuru 7 up to the moving position (control position) of the finger 1 is not the same, so if these different amounts of move are changed at the same speed, a certain masulu 7 will complete the moving operation. However, it happens that the movement operation of the other Masle 7 is still in progress. This not only makes the movement of the finger 1 awkward and unnatural, but also causes the movement path of the finger 1 to deviate from the target path and come into contact with an obstacle. Therefore, each mass 7 within the same time
The moving speed data MS (MS1, MS2, MS3) for each of the masles 7 is set so that the moving operation of No. 3 is just completed, and the movement of each masle 7 is controlled by these moving speed data to make it the same as the final control position. It must be controlled so that each Masle moves at the timing. The moving speed data Ms (Ms1, Ms2, Ms3) of each of the masles 7 is obtained from the above-mentioned motors 10
It is obtained by dividing the number of revolutions TM (TM1, TM2, TM3) of the above by a predetermined moving time.

In this process, the speed data FS of the finger 1 is stored (set) in the memory I33 in advance, and from the set (designated) finger speed data FS,
According to the following equation, MS1 = TM1 / FS MS2 = TM2 / FS MS3 = TM3 / FS, the moving speed data MS (MS1, MS2, MS3) of each massus is obtained.

Based on the rotation speed TM (TM1, TM2, TM3) of the motor 10 and the masle movement speed data Ms (MS1, MS2, MS3) thus calculated, the rotation control of the motor 10, that is, the movement control of the masle 7 is performed. Is performed as follows. In the following processing, the latch S1 built in the CPU 31
Each of the rotation sensors 25a, 25 by 1, S12, and S13
The outputs of b and 25c are latched to detect the output of each rotation sensor.

First, the moving speed data M of each of the above-mentioned maslu 7
The voltage for driving each motor 10 is set based on S (MS1, MS2, MS3) (step S5). In this processing, the massle moving speed data MS (MS1, MS2, MS
According to 3), the motor energization voltage (current) is adjusted to control the moving speed of each masuru 7. Alternatively, each massle 7 is driven by a duty pulse drive of an energizing voltage.
To control the speed of movement. In the case of a motor such as a stepping motor whose rotation speed is controlled by a motor drive signal, the motor drive signal is generated according to the value of the moving speed data MS. .

In this speed control, the relationship between the motor rotation speed and the voltage value is obtained in advance, and this relationship table is stored in the memory I (or II or III). Alternatively, the relationship between the duty pulse value and the motor rotation speed is obtained in advance, and the relationship table is stored in the memory I (or II, or II).
I) to remember it. Then, the calculated moving speed data MS (MS1, MS2, MS)
The motor control value (voltage value or duty pulse value) corresponding to 3) is taken out from the above table and each motor 1
0 rotation speed is controlled.

On the other hand, the output of the rotation sensor 25 is latched by the latch S1.
While always detecting the rotation speed of each motor 10 by detecting S1, S12 and S13, the voltage value or duty pulse value of the motor energization is controlled to control the moving speed of each masuru 7.

As a result, the large moving massule 7 is controlled to move fast, and the small moving massule 7 is controlled to move slowly so that the three massules 7 are located at the target position (the length of the control position). It can be controlled to reach at the same time.

Subsequent to the above, the value of the rotation speed TM1 of the motor 10a calculated in the above step S3 is checked (step S6). If TM1 ≠ 0, that is, if TM1 <0 or TM1> 0, the process proceeds to step S7.

In step S7, if TM1 <0 in the determination in step S6, the control position is in the negative direction relative to the current position with respect to the mascule 7a. Therefore, in this case, the motor 10a is turned on. Rotate in the opposite direction (step S71). Then, it is determined whether or not the latch S11 latches the encoder detection signal "1" of the rotation sensor 25a (step S72). If the latch S11 latches the encoder detection signal "1", the motor 10a
Has rotated once in the opposite direction, that is, the masle 7a has moved from the current position AP1 in the control direction, that is, in the negative direction by one rotation of the motor. In this case, the value of the rotation speed TM1 of the motor 10a is incremented by "1". Then, the remaining rotational speed is set and the value of the current position data AP1 is decremented by "1" to update the current position during movement (step S
73), the latch S11 is further initialized to "0" (step S74), and the process proceeds to step S9 described later. If it is determined in step S72 that the latch S11 has not yet latched the encoder detection signal "1", the motor 10
Since a has not yet made one revolution, in this case, the process immediately proceeds to step S74.

On the other hand, TM1> 0 in the determination in step S6.
If it is, the control position is more positive than the current position with respect to the masle 7a, and therefore
In this case, the motor 10a is rotated in the forward direction (step S75). Then, also in this case, it is determined whether or not the latch S11 latches the encoder detection signal "1" of the rotation sensor 25a (step S76). If the latch S11 latches "1", the motor 10a makes one revolution in the positive direction and the masle 7a moves from the current position AP1 to the control direction, that is, one revolution in the positive direction. Therefore, in this case, the value of the rotational speed TM1 of the motor 10a is decremented by "1" to set the remaining rotational speed, and the value of AP1 is incremented by "1" to update the current position during movement (step S77), the latch S of the above step S74
Initialize 11. If the latch S11 has not yet latched "1" in step S76, the motor 1
Since 0a has not yet made one revolution, in this case, the process immediately proceeds to step S74.

Further, in the judgment of the above step S6, TM1 =
If it is 0, it means that the masle 7a has reached the target control position by repeating the above-mentioned movement processing, or it is not necessary to move from the beginning to the current position. Therefore, in this case, the motor 10a is turned on. Stop (step S
8) and then to the following step S9.

In step S9, the value of the rotation speed TM2 of the motor 10b calculated in step S3 is checked. Then, TM2 ≠ 0, that is, TM2 <0 or TM2> 0
If so, the process proceeds to step S10. In step S10, although not shown, the same processing as step S7 described above is performed on the motor 10b and the latch S12.

That is, TM2 is determined by the determination in step S9.
In the case of <0, the motor 10b is rotated in the reverse direction to move the massle 7b in the negative direction, and it is determined whether or not the latch S12 latches the output "1" of the rotation sensor 25b,
If "1" is latched, the value of the rotation speed TM2 of the motor 10b is incremented by "1" and the value of the current position AP2 is decremented by "1", then the latch S12 is initialized and the process proceeds to step S12 which will be described later. On the other hand, if "1" is not latched, the latch S12 is immediately initialized and the process proceeds to step S12.

Further, in the determination of the above step S9, TM2>
In the case of 0, the motor 10b is rotated in the positive direction to move the mascule 7b in the positive direction, and the latch S12 causes the rotation sensor 2 to move.
It is determined whether or not the output “1” of 5b is latched,
If "1" is latched, the value of the rotation speed TM2 of the motor 10b is decremented by "1" and the value of the current position AP2 is incremented by "1", then the latch S12 is initialized and the process proceeds to the next step S12. On the other hand, if "1" is not latched, the latch S12 is immediately initialized and step S1
Proceed to 2.

Further, in the determination of step S9, TM2 =
If it is 0, the motor 10b is stopped (step S1).
1) Go to step S12. Also in step S12, the value of the rotation speed TM3 of the motor 10c calculated in step S3 is checked, and TM3 ≠ 0 (TM3 <0 or TM3> 0)
If so, the process proceeds to step S13, and the same process as the process of step S7 or step S10 described above is performed on the motor 10c and the latch S13. On the other hand, if TM3 = 0 in step S12, the mascule 7c is in the control position, and in this case, the motor 10c is stopped (step S14).

Then, in this case, first, the value of the rotation speed TM1 of the motor 10a is checked to determine whether or not the masuru 7a is at the control position (step S15). When the rotation speed TM1 of the motor 10a is not "0" (TM1 ≠ 0), at least the mascule 7a has not yet reached the control position. In this case, the process returns to the above step S6 and the above steps S6 and thereafter. Process again. This allows
The drive control of the motor 10a and the motor 10b is continued.

In step S15, the motor 10a is
If the value of the rotation speed TM1 of the motor is “0” (TM1 = 0), the mascule 7a is in the control position, and the motor 10a is in step S
It stopped at 8. In this case, the value of the rotation speed TM2 of the motor 10b is further checked to determine whether or not the masuru 7b is at the control position (step S16). And motor 1
When the rotation speed TM2 of 0b is not "0" (TM2 ≠ 0),
Since the muscle 7b is not yet in the control position,
In this case, the process returns to step S6, and the processes of step S6 and subsequent steps described above are performed again. As a result, the motor 10
The drive control of b is continued.

If the value of the rotation speed TM2 of the motor 10b becomes "0" (TM2 = 0) in the above step S16 by repeating the above-mentioned processing, the masuru 7b has also come to the control position, and the three units Since the motors 10 of 10 are all stopped, the processing ends.

As described above, the forward / backward drive of each masle 7 can be accurately performed by controlling the rotation of the motor independently provided for each masle. For example, when controlling the movement of the circular orbit (r = 10) of the finger 1 shown in FIG. 6 (b), the position data LM (LM1, LM2, LM3) of each masle 7 is processed in the above-mentioned control process. By controlling so that takes the value shown in FIG. 6 (a), a circular orbital motion can be realized.

A motor of the type for controlling the rotation by a motor drive signal, such as a pulse motor or the like for the above-mentioned motor for driving a massle, can detect the number of rotations by the motor drive signal, so that a rotation sensor is provided. It can be said that it is not necessary to check the output, but when the load on the tip of the finger is relatively heavy or when there is a large change in load, even a pulse motor may not always rotate according to the motor drive signal. . Therefore,
It is considered that the control accuracy is improved by providing a rotation sensor to check the rotation speed of the motor.

Further, the above-mentioned position control has been described as controlling the center position of the root of the finger of the finger 2 on the Masul root (the position of the center point M of the bottom surface of the finger 2).
When controlling the operating position by using another part of the finger tip 2 as the focus point, the finger tip 2 described in FIG. 5 (c) is used.
Coordinate data M (Mx, My, Mz) of the bottom center point using the coefficients ftx, fty, and ftz based on the shape of
Is corrected, and the maslu 7 is driven based on the corrected position of the bottom center point M.

Also, as the current position data of the massle 7,
Motor rotation amount data AP (AP1, AP2, from the reference position)
AP3) is always stored in the memory II, but finger position data FA [M
(Mx, My, Mz) or M ([theta] M, [alpha] M, Mz)] may be stored, and the present Masru current position data may be obtained by the above-mentioned arithmetic processing at each control. However, in this case, it takes more processing time than the method shown in FIG.

By the way, the position of the masuru 7 during the control of the finger 1 is changed from its original position when receiving noise, when the finger 1 moves by an external force, or when the control power supply is cut off during operation. It will shift. Therefore, if the finger 1 is continuously controlled as it is, the control accuracy cannot be obtained.

Next, a method of correcting the position data of the mastles 7 in order to control the movement of the finger 1 described above more accurately will be described. First, in order to confirm the position of the finger 1, as shown in FIG. 3 described above, the position sensor 26 is arranged so that the reference position of each masle 7 can be detected in at least one portion. In the example shown in the figure, the sensor 26 is arranged at a position for detecting the slide screw nut 14 of each masle 7 when the slide screw nut 14 reaches the position where the masle 7 is the longest (the right end in the drawing). This position sensor 26
It is composed of an LED and a phototransistor, and the light emitted from the LED is reflected by the slide screw nut 14, and the reflected light is received by the phototransistor. The configuration is such that the position of the slide screw nut 14, that is, the reference position of the masle 7 is detected without the presence of this reflected light.

As another method, although not particularly shown, a mechanical switch such as a micro switch is arranged at the position of the position sensor 26 shown in FIG. 3, and the mechanical switch is operated by moving the slide screw nut 14. In this way, when the mechanical switch operates, it may be configured to detect that the mechanical switch 7 has arrived at the reference position. With these configurations, the position of each masle 7 is detected at at least one site.

FIG. 14 shows each of the mascule 7 in the above structure.
6 is a flowchart illustrating the operation of a process of determining the reference position of FIG. By this processing, the deviation of the control position of each masle 7 can be corrected. In addition, in this process, the reference position data of each massle is set to "AB (AB1, AB2, AB3)".
It is expressed as This Masuru reference position data AB (A
The dimension (unit) of (B1, AB2, AB3) is the rotation unit of the screw shaft 11 or the rotation speed of the motor 10. This Masuru position data AB (AB1, AB2, AB3)
Are stored (stored) in a predetermined area of the memory I (or II or III). Further, in this processing, each output of the above-described position sensor 26, that is, the slide screw nut 1
4a, the output of the position sensor 26a that detects the slide screw nut 14b, and the position sensor 26c that detects the slide screw nut 14c.
Will be described as signals S21, S22, and S23, respectively.

In the flowchart shown in FIG. 14, it is first determined whether or not the signal S21 is "1" (detection output of the slide screw nut 14a) (step S2).
1). If S21 = "1", the slide screw nut 14a is at the detection position of the position sensor 26a. In this case, the motor 10a is rotated in the reverse direction to move the masle 7
The slide screw nut 14a is moved in the direction in which a is pulled in (left in FIG. 3) (step S22). This process
Due to an error in the drive mechanism of the slide screw nut 14a, a screwing error with the screw shaft 11a, and the like, there is a slight difference in the position where the slide screw nut 14a is detected by the position sensor 26a depending on the moving direction of the slide screw nut 14a. Therefore, the massul 7a for updating (correcting) the reference position of the massul 7a by this detection.
In order to obtain the absolute position of, the position of the masuru 7a must always be detected under the same conditions. In the case of this example, the position sensor 26a from the left detection position to the right position sensor
The detection condition is always the same when moving to the detection position. Therefore,
When the slide screw nut 14a is already at the detection position of the position sensor 26a, the slide screw nut 14a is temporarily excluded from the detection position to the left of the detection position. Therefore, when the slide screw nut 14a is at the detection position of the position sensor 26a as described above, the motor 10
The slide screw nut 14a is moved in the direction in which the a is rotated in the reverse direction to pull in the mascule 7a. On the other hand, if S21 ≠ “1”, that is, S21 = “0” in step S21, the slide screw nut 14a is outside the detection position of the position sensor 26a, and in this case, the motor 10a is stopped (step S23). ).

In any of the above cases, it is then determined whether or not the signal S22 is "1" (detection output of the slide screw nut 14b) (step S24). And
If S22 = "1", it is determined that the slide screw nut 14b is at the detection position of the position sensor 26b, and in this case also, the motor 10b is rotated in the reverse direction, and the slide screw nut 14b is moved in the direction in which the mastle 7b is pulled in. (Step S25). Thus, when the slide screw nut 14b is already at the detection position of the position sensor 26b, the slide screw nut 14b is temporarily excluded from the detection position to the left of the detection position. On the other hand, in step S24, S22 ≠
If it is "1" (S22 = "0"), it is determined that the slide screw nut 14b is outside the detection position of the position sensor 26b, and the motor 10b is stopped (step S26).

Then, in any of the above cases, it is subsequently determined whether or not the signal S23 is "1" (detection output of the slide screw nut 14c) (step S2).
7). If S23 = "1", it is determined that the slide screw nut 14c is at the detection position of the position sensor 26c, the motor 10c is rotated in the reverse direction, and the slide screw nut 14c is moved in the direction to pull in the masuru 7c. (Step S28), the process returns to step S21.

As a result, when the slide screw nut 14c is already at the detection position of the position sensor 26c, the slide screw nut 14c is once removed from this detection position to the outside of the left detection position. On the other hand, in step S27, S23
If ≠ "1" (S23 = "0"), it is determined that the slide screw nut 14c is outside the detection position of the position sensor 26c, the motor 10c is stopped (step S29), and then the above-mentioned signal S21. Is determined to be "1" (step S30).

If S21 = "1" in this determination, the process returns to step S21, S21 = "1" is confirmed, and the reverse rotation drive of the motor 10a is continued in step S22.
The steps of S26, S27, S29, and S30 are repeated. Then, in step S30, S21 =
If it becomes "0", then it is judged whether or not the signal S22 becomes "1" (step S31). Then, if the signal S22 = "1", in this case also the above step S2
Returning to step 1, the signal S21 ≠ “1” is first confirmed, and step S
The motor 10a is continuously stopped in step S23, and the signal S22 = "1" is confirmed in step S24. Therefore, the reverse rotation of the motor 10b is continued in step S25, and steps S27 and S2 are performed.
9. Repeat steps S30 and S31.

Then, in the above step S31, S22
When it is determined that all the slide screw nuts 14 have moved out of the detection positions of the position sensors 26 corresponding to each other by becoming "0", then the motor 10a is rotated in the forward direction (step S32). The motor 10b is also rotated in the forward direction (step S33), and the motor 1
0c is also rotated in the positive direction (step S34). As a result, the three slide screw nuts 14 corresponding to the three masles 7 start to move from outside the detection position of the position sensor 26 (left side in FIG. 3) to the detection position all at once.

Then, following the above, the signal S21 is "0".
Or not (step S35), S21 =
If it is "0", it is determined that the slide screw nut 14a has not reached the detection position yet, and nothing is done (the rotation drive of the motor 10a which has already been performed is left, that is, continued),
Next, it is determined whether or not the signal S22 is "0" (step S37). Also here, if S22 = "0", it is determined that the slide screw nut 14b has not reached the detection position yet, nothing is done, and it is immediately determined whether or not the signal S23 is "0" (step S39). ). Then, if S23 = "0", it is determined that the slide screw nut 14c has not reached the detection position yet, nothing is done, and the process returns to the above step S35 to repeat steps S35, S37, and S39. As a result, as described above, the slide screw nuts 14 that have started to move from the outside of the detection position of the position sensor 26 to the detection position all at once continue to move, and eventually reach the detection position at their respective timings.

When the slide screw nut 14a has reached the detection position (S21 ≠ “0”), the above step S
When the determination is made at 35, the motor 10a is stopped (step S36), and steps S37, S39, and S35 are repeated. Further, the fact that the slide screw nut 14b has reached the detection position (S22 ≠ “0”) means that the above step S3.
When it is determined in step 7, the motor 10b is stopped (step S36) and steps S39, S35, and S37 are repeated. Alternatively, when the slide screw nut 14c reaches the detection position (S23 ≠ “0”), the above step S
When the determination is made in 39, the motor 10c is stopped (step S40), and then it is determined whether or not the slide screw nut 14a has also reached the detection position (step S5).
0), if not yet reached, the above steps S35 and thereafter are repeated. On the other hand, when the slide screw nut 14a has reached the detection position, the slide screw nut 1
It is determined whether or not 4b has also reached the detection position (step S51). If it has not yet reached the detection position, step S35 and subsequent steps are repeated in this case as well. As a result, each slide screw nut 14 that has moved from outside the detection position of the position sensor 26 to the detection position at each timing is detected at the detection position, and stops at that detection position.

As described above, the position where the slide screw nut 14 is detected under the same condition (moving from outside the detection position to the detection position) is always the same position with respect to the guide plate (bearing plate) 4. That is, at this time, the length from each guide hole 6 of each masuru 7 to the finger tip portion 2, that is, the positions M01, M02, and M03 on the reference surface 3 of the masulu 7 from the fixing point M1 to the bottom surface of the finger tip portion 2 are set. , M2
, And the length up to M3 always have the same value. The position of each maslu 7 in this length is defined as an absolute position, and the position data of the maslu 7 at this time is the absolute position data of the maslu AB
As (AB1, AB2, AB3), the memory I (or II, or
(III) is stored in a predetermined storage area (step S5)
2). Then, the initial position of the finger 1 is set, for example, by retracting each of the mastles 7 from the absolute position by a predetermined amount (step S53), and the mastle position correction process ends.

As described above, the processing for correcting the position of the massle is performed at an appropriate time, and the amount of advance / retreat of each of the massles 7 is controlled with reference to the initial position reset by this, so that the accuracy of the finger 1 is improved. Achieve good control.

By the way, there are various cases in which the above correction is performed. For example, it is automatically performed when the power is turned on. Automatically at the start of finger operation. Automatically when the slide screw nut reaches the detection position of the position sensor during finger operation control. The operation is automatically performed when the operation time or the number of times of the muscle is equal to or longer than a predetermined time or the number of times and the massle is not detected by the position sensor. Manual operation by key input. It can be considered that the command is executed when a command (command) for correcting the massle position data is input from the control input terminal of the device.

FIG. 15 is a flow chart of the process in the case where the correction is carried out with the above cases as the conditions for determining the timing. In this processing, three time counters Ct1, Ct2, and Ct3 built in the CPU 31, a latch S21 that latches the output of the position sensor 26a shown in FIG. 3, a latch S22 that latches the output of the position sensor 26b, and A latch S23 that latches the output of the position sensor 26c is used. Further, a period (time Q) for forcibly performing the correction is set in advance in the memory I or a register or the like built in the CPU 31. Hereinafter, this process will be described.

First, the time counters Ct1, Ct2, and Ct3
To start time measurement (step S61). This processing is inserted before the motor control processing during the finger control processing shown in the flowchart of FIG.

Subsequently, automatic correction processing is performed (step S62). This process is inserted into an appropriate procedure of the motor control process during the finger control process shown in the flowchart of FIG.

The process of step S62 will be further described below. First, the output of the latch S21 is checked (step S
62-1). If S21 ≠ “0” (the output of the latch S21 is not “0”, and so on), that is, S21 = “1” (the output of the latch S21 is “1”, and so on), the slide screw nut 14a is used as the position sensor. 26a, that is, the massule 7a is judged to have come to the absolute position, and the current position data AP1 of the massle 7a at this time is stored in a predetermined storage area of the memory I (or II or III). The absolute position data AB1 of the stored massle 7a is replaced (step S62-2). As a result, the absolute position data AB1 of the masle 7a is updated (corrected). After the above processing, the time counter Ct1 is cleared to "0" (step S62-3). As a result, the timing of the next position data correction of the masle 7a (correction timing by time) is newly measured. Subsequent to this, step S62-4 and later described below are performed. In step S62-1, S21 =
If it is "0", the masuru 7a has not come to the absolute position, and in this case, step S62-4 and thereafter are immediately performed. In this way, when controlling the finger 1,
The absolute position of the masle 7a is reset by using the time when a comes to the detection position of the position sensor 26a, and thereby the error that may have occurred is corrected.

In steps S62-4 to S62-6 also in this case, the output of the latch S22 is first checked (step S6).
2-4). If S22 ≠ “0” (S22 = “1”), the current position data AP2 of the mascule 7b is stored in the memory I (or II,
Or III) stored in a predetermined storage area 7)
The absolute position data AB2 of b is exchanged (step S
62-5). As a result, the absolute position data AB2 of the masle 7b is updated (corrected). Then, the time counter Ct2 is cleared to "0" to newly measure the timing of the next position data correction of the mascule 7b (step S62-6).
The step S62-7 and subsequent steps, which will be described later, are performed. If S22 = "0" in step S62-4, steps S62-7 and thereafter are immediately executed. Thereby, in the control of the finger 1, the absolute position of the maslu 7b is reset by using the time when the masuru 7b reaches the detection position of the position sensor 26b.
Correct the error that may have occurred.

Subsequently, steps S62-7 to S62-9.
In the same manner, first, the output of the latch S23 is checked (step S62-7). Then, S23 ≠ “0” (S23 = “1”)
If so, the current position data AP3 of the massle 7c is stored in the memory I (or
The absolute position data AB3 of the muzzle 7b stored in the predetermined storage area II or III) is replaced (step S62-8). As a result, the absolute position data AB3 of the mass 7c is updated (corrected). Next, the time counter Ct3
Is cleared to "0" to newly measure the timing of the next position data correction of the massle 7c (step S62-
9) Then, step S63 and the subsequent steps, which will be described later, are performed. If S23 = "0" in step S62-7, steps S63 and thereafter are immediately performed. As a result, in the control of the finger 1, the absolute position of the maslu 7c is reset by using the time when the masuru 7c reaches the detection position of the position sensor 26c, and an error that may have occurred is corrected.

In the flow indicated by the broken line in step S62, the above processing may be repeated at a predetermined cycle, or the above processing may be bypassed to perform the processing of step S63 and thereafter. It shows that. The processing in and after step S63 is not performed by using the time when the muzzle 7 reaches the detection position of the position sensor 26 during the control of the finger 1 as in the above-described case, but is forcibly performed at regular intervals. It is to make a correction. This is because the maslu 7 is controlled during the control of the finger 1 only by utilizing the time when the masuru 7 reaches the detection position of the position sensor 26 as described above.
In some cases, the correction may not be possible because the position may never come to the detection position of the position sensor 26. In order to avoid this, the correction is forcibly performed at regular intervals. This processing will be described below.

First, the time counters Ct1, Ct2, and Ct3
The clocking of is stopped (step S63). Next, the value of the currently stopped time counter Ct1 is checked (step S6).
4). If Ct1 ≧ Q (the value of the time counter Ct1 is equal to or exceeds the set time Q, the same applies below), the time counter Ct1 is cleared to “0” and the period until the next forced correction is counted from the beginning. After doing so (step S6
5), the position of the massle 10a is corrected (step S6).
6). This process corresponds to steps S21 to S23, S32, S35, S36 and S52 in the process shown in FIG.
And the processing of S53. As a result, when the fixed period (time Q) has elapsed, that is, when the position correction of the mastle 7a is not performed within the set time Q, and therefore the time counter Ct1 is not cleared to "0", it is forcibly forced. The position of the muscle 7a is corrected. After this processing, step S67 and subsequent steps described later are performed. If Ct1 <Q in the step S64, the step S64 is immediately executed.
Do 67 or less.

In the processing from step S67 onward, the value of the time counter Ct2 is first checked in this case as well (step S6).
7). If Ct2 ≧ Q, the time counter Ct2 is cleared to “0” and the period until the next forcible correction is measured from the beginning (step S68).
The position is corrected (step S69). This process
Steps S24 to S2 in the process shown in FIG.
The process is the same as the process of S6, S33, S37, S38, S52, and S53. As a result, if the position correction of the mastles 7b is not performed even after the time Q has elapsed, the position correction of the mastles 7b is forcibly performed. After this processing, step S70 and later described below are performed. If Ct2 <Q in step S67, immediately step S70.
Do the following:

In the processing from step S70 onward, also in this case, the value of the time counter Ct3 is first checked (step S7).
0). If Ct3 ≧ Q, the time counter Ct3 is cleared to “0” and the period until the next forcible correction is measured from the beginning (step S71).
The position is corrected (step S72). This process
Steps S27 to S2 in the process shown in FIG.
The processing is the same as the processing of 9, S34, S39, S40, S52, and S53. As a result, if the position correction of the mastles 7c is not performed even after the time Q has elapsed, the position correction of the mastles 7c is forcibly performed. After that, the correction process ends. Further, in step S70, Ct3 <
If it is Q, the processing is immediately terminated.

The position correction is performed when a predetermined time elapses for each of the mastles 7, and the support process is performed when the correction cannot be performed in the process of step S62. Even if the processing of S62 is not performed from the beginning (bypassing), and when a certain period of time has always elapsed, the processing of FIG. 4 may be performed to forcibly correct the positions of the three masles 7 at once. Good.

By the way, as described above, the movable length LMmax and the minimum length LMmin of each masle are set in advance so that the finger 1 can be controlled in a uniform range in all directions. I have a limit. Therefore, in the processing for controlling the finger 1 described above, when the control data (data for designating the moving destination of the finger 1) designates the movement outside the limited range, it is necessary to perform the error processing. Further, as described above, the movement range is not limited to the case where uniform movement in all directions is assumed, and depending on the work environment, the movement limit range may differ depending on the direction due to the presence of a fixed obstacle or the like. is there.

In such a case, first, the allowable movement range (limitation range) of the finger 1 is set. This limited range is the actual operating range of the finger 1 or a range narrower than that. Then, the shortest value LMHmin (LMH1min, LMH2min,
LMH3min) and the longest value LMHmax (LMH1max, LMH2max, L
MH3max) is obtained from the equations (Equation 15) to the equation (Equation 20). The obtained minimum value LMHmin and maximum value LMHmax are converted into a control data unit, for example, a screw shaft rotation speed unit or a motor rotation speed unit.

When converting to the screw shaft rotational speed unit, LMSmin (LMS1min, LMS2min, LMS3min) = k1.LMHmin (LMH1min, LMH2min, LMH3min) LMSmax (LMS1max, LMS2max, LMS3max) = k1.LMHmax (LMH1max, LMH2max, LMH2max, LMH2max, LMH2max, LMH2max, LMH2max LMH3max), the limit value LMSmin and L
MSmax is obtained. The coefficient k1 is the number of rotations of the screw shaft per unit distance of movement of the masle, as described above.

Further, in the case of conversion into the motor speed unit, LMTmin (LMT1min, LMT2min, LMT3min) = k1.k2.LMHmin (LMH1min, LMH2min, LMH3min) LMTmax (LMT1max, LMT2max, LMT3max) = k1.k2.LMHmax (LMH1max, LMH2max, LMH3max), the limit value LMSmin and L in units of motor speed
MSmax is obtained. As described above, the coefficient k2 is a coefficient determined by the motor rotation speed / screw shaft rotation speed.

The limit value thus obtained in advance is stored in the memory I (or II, or III) as the movement range limit data of each mastle 7 in a certain direction in which the finger 1 moves.
Stored in a predetermined area of. In this way, the control data of the limit range in a certain fixed direction in which the finger 1 moves is uniquely defined as the movement range limit data of one set of each massle 7 if the direction and the limit range are predetermined. I can decide. For example, if the unit is the screw shaft rotation speed, “LMSmin
, LMsmax ", and if it is the unit of motor rotation speed,
Tmin, LMTmax ".

The above-mentioned mass movement range restriction data is
If there are multiple directions that are restricted by the specification mode or the environmental conditions, a plurality of masulu movement range restriction data, for example, motor rotation speed units, “LMTmin-1 and LMTmax-1” are set in advance for each specification mode or environmental condition. ,
A plurality of sets of data, such as “LMTmin-2, LMTmax-2”, ... Are stored in the memory as movement range limiting data in each limiting direction and are prepared in advance, and a specification mode for controlling fingers is provided. Alternatively, the data may be appropriately selected from among a plurality of prepared massle movement range restriction data according to environmental conditions and the like. Further, the CPU 31 may calculate and generate the massle movement range restriction data each time in accordance with the specification mode, the environmental condition, and the like.

FIG. 16 is a flow chart of error processing when the movement of the finger 1 is specified beyond the limit range. In this process, the movement range limitation data "LMTmin, LMTmax" in units of the number of rotations of the motor is stored in advance in the memory II as the movement range limitation data of the mastle 7.

In the finger control shown in the figure, when finger control data is given, first, the finger position data FA, that is, the coordinates M (Mx, MY, Mz) or the coordinates M (θM, αM, Mz), is used to determine the position of the masle. Data L
M (LM1, LM2, LM3) is obtained (step S81).
This process is the same as the process of step S1 shown in the flowchart of FIG.

Subsequently, the massle position data LM (LM
Rotation amount data LMT (LMT1, LMT2, LMT3) in units of the number of motor revolutions is obtained from (1, LM2, LM3) (step S82). This process is the same as the process of step S2 shown in the flowchart of FIG.

Then, the obtained rotation amount data LMT is
It is compared with the longest limit data LMTmax of the moving range of the massle 7 read from the memory II (step S83). Then, the calculated rotation amount data LMT (LMT1, L
MT2, LMT3) is the longest limit data LMTmax (LMT1ma
x, LMT2max, LMT3max) (LMT <LM
Tmax), and then the above-mentioned rotation amount data LMT is compared with the shortest limit data LMTmin of the moving range of the massle 7 which is also read from the memory II (step S84). Then, the rotation amount data LMT (LMT1, LMT2, LMT3) is
If it is larger than the shortest limit data LMTmin (LMT> LMT
max), the movement amount of the masle 7 is shorter than the longest limit data and longer than the shortest limit data, so the finger control data indicates that it is within the movement limit range of the finger 1 and is therefore normal. It is determined and the same process as step S3 in FIG. 13 is performed to obtain the motor rotation speed TM (TM1, TM2, TM3) from the current position to the designated position (step S85). Then, step S of FIG.
The same processing as in 4 is performed to calculate the moving speed data MS (MS1, MS2, MS3) of each masle 7 (step S8).
6). Then, the motor control process is performed in the same manner as the process shown in and after step S5 of FIG. 13 (step S87).
Thereby, if the movement of the finger 1 is within the limit range, the control of the maslu 7 is normally performed.

On the other hand, at the step S83, "LMT≥LMT
max "or" LMT≤LMTmax "in step S84.
, The finger control data exceeds the movement limit range of the finger 1. Therefore, in this case, without performing finger control, a warning notification is issued by, for example, driving the lighting of a display such as a red light emitting element, a warning notification by voicing a sounding device such as a buzzer, or a warning notification by a specific operation of the finger. Warning notification of (step S8
8) The error command is sent back to the control terminal of the control circuit (step S89). As a result, a predetermined error post-processing corresponding to the error occurrence is performed.

As a result, even if erroneous control data is input, it is easy to notify the error before the finger 1 starts moving and to shift to an appropriate process corresponding to the error. The possibility of adversely affecting the peripheral device or the main body device is eliminated.

In the configuration of the above embodiment, each motor 10 is housed in the motor housing 13 and rotatably supported in the case 8 of the drive unit 5, and is configured as a single unit. It is not limited. Next, another example of the configuration of the motor will be described below as a second embodiment.

FIG. 17 is a partially cutaway perspective view showing the structure of a finger in which a part of the motor housing of the second embodiment and the guide plate are integrated. It should be noted that in the same figure, the illustration of the finger tip portion and the mastles on the tip portion fixed side is omitted. In addition, the same components as those shown in FIGS.
~ The same numbers as in Fig. 3 are attached.

As shown in the figure, the finger 1b is
Motor housing 1 for motors 10a, 10b and 10c
The bearings of 3a ', 13b' and 13c 'are gear parts 1
It is integrated with the guide plate 4-2 on the side opposite to 2. That is, the shaft end of each motor 10 opposite to the gear portion 12 is supported by the guide plate 4-2. Thus, the motor housings 13a ', 13b' and 13c '
One bearing surface is removed so that the bearing on this side is shared by the guide plate 4-2. Incidentally, the other components, that is, the guide holes 6 (6a, 6c in the figure) of the maslu
, Masle 7 (7a, 7b, 7c), case 8, screw shaft 11 (11a and 11c are visible in the figure), gear part 12, and slide screw nut 14 (only 14a is visible in the figure) 1 to 3 are the same as those shown in FIG.

As described above, by removing one bearing surface of the motor housing so that the bearing surface on this side is shared by the guide plates, not only the component structure is simplified, but also the finger 1b is It can be made smaller.

Further, in each of the above-mentioned first and second embodiments, the motor of the type in which the driving magnetic field is formed through the outside of the motor is used, but the motor is not limited to this, and the magnetic field of the motor is not limited to this. A type that passes through the inside may be used. This will be described below as a third embodiment.

FIG. 18 is a partially cutaway perspective view showing the structure of a finger in which the motor housing and the case are integrated. Also in the case of this figure, the illustration of the finger tip portion and the mastles on the tip portion fixing side is omitted. Further, the same components as those shown in FIGS. 1 to 3 are designated by the same reference numerals as those shown in FIGS.

The finger 1c shown in the figure is a coreless motor 40 (40a, 40b, 40c) for driving the masle 7.
Are using. Since a coreless motor is a type of motor that allows a magnetic field to pass through inside the motor, an independent housing for each motor is not necessary as long as the whole can be protected. Therefore, as shown in FIG.
Inside each coreless motor 40 is exposed,
The housing for protecting these is configured to be shared by the case 8. Also in this case, the shaft ends 41a, 41b, and 41c of the coreless motor 40 on the side opposite to the gear portion 12 are supported by the bearings 42a, 42b, and 42c of the guide plate 4-2, respectively. Two
Is also used as a motor bearing plate. In addition, other components, that is, the guide holes 6 (6a in the figure,
6c can be seen), masle 7 (7a, 7b, 7c), case 8, screw shaft 11 (11a, 11b, 11)
c), gear portion 12, slide screw nut 14 (in the figure, 1
4a is visible) and the position sensor 26 (26a, 26a
b, 26c) are the same as those shown in FIGS. In this way, by removing the motor housing and sharing the cover for protecting the motor with the case 8 of the drive unit, a relatively large component called the motor housing can be reduced and a smaller finger can be configured. You will be able to.

In each of the above-described first to third embodiments, the three maslus 7 are each driven, but the driving of the maslus is not limited to this, and one may be fixed and the other. 2 may be driven, or the two may be fixed and the remaining one may be driven. Hereinafter, these will be described.

FIGS. 19A and 19B are views showing the structure of a two-massle drive type finger of the fourth embodiment. FIG. 19A is a partially cutaway perspective view of a drive section, and FIG. 19B is a bottom sectional view. . Figure (a)
The illustration of the finger tips and the mastles on the side where the tips are fixed is omitted. Further, the same components as those shown in FIG. 1 or 2 are designated by the same reference numerals as in FIG. 1 or 2.

As shown in FIGS. 19 (a) and 19 (b), this finger 1-4 has the same structure as the finger 1 shown in FIGS.
Alternatively, one of the three masle units (see FIG. 3) forming the finger drive portion having the configuration of the finger 1-2 shown in FIG. The drive part is removed. 19 (a) and 19 (b), in the configuration shown in FIG. 1 and FIG. 2, the third massle unit drive part including the motor 10c, the gear part 12c, the screw shaft 11c, and the slide screw nut 14c is removed. , The end portion on the side of the drive portion is fixed to the guide plate 9 except for the maslu 7c. Of course, the end portion of the mastle 7c on the drive unit side may be fixed to the guide plate 4 or the like.

One masle 7c with both ends fixed
Has elastic force similar to the other two maslu 7a and 7b, and has a shape from the maslu guide hole 6 (reference surface of the guide plate 4) to the tip of the finger when the fingers 1-4 are in the initial position. Is in the same state as the other two maslu 7a and 7b. The fingers 1-4 control the movement of the fingers by controlling the positions of the two massles 7a and 7b having the unit drive system. The finger having this configuration is effective when the moving range of the tip portion of the finger is narrow, as will be described later in detail.

Also in the case of the fingers 1-4, other configurations are similar to those of the first to third embodiments, and although not particularly shown, the unit drive system is provided with a rotation sensor and a position sensor. . Further, the control circuit shown in the circuit block diagram of FIG. 12 is provided, and the fingers 1-4 are controlled based on the algorithm shown in the flowcharts of FIGS. That is, the control method may be such that the length of one masle is fixed and the lengths of two masles are controlled. Further, the correction method may be performed on two driven massles,
Further, the error detection method may be performed in the same manner by setting the limit range in advance.

Next, the finger 1-controlled in this way is
The range of movement of 4 (movement of the tip portion) will be described. The fingers 1-4 cannot move up and down as shown in FIG. 4 (a), but the bending movement as shown in FIG.
It can be done in a range. The control of this bending movement is
In the processing of the first embodiment, one of the masle lengths LM (the length LM3 of the maslu 7c in the example of the configuration shown in FIG. 19) is set as a fixed length, and the position data can be calculated. In this case, the angle αM of the bending direction is determined by the position of the fixed length masle 7c.

FIGS. 20 (a), (b), (c), and (d) are views for explaining the movement control range of the two-massle drive type fingers, and FIGS. 21 (a), (b), (c) is a graph for explaining the finger movement control range.

FIG. 20 (a) corresponds to FIG. 7 (a), (b) or FIG. 8 (a),
Similar to the one shown in (b), the placement position M01 of each of the masles 7 (7a, 7b, 7c) on the reference plane of the guide plate 4,
M02 and M03 are shown together with their circumscribing circles, and the finger tip center point M (Mx, My, Mz) is shown in three-dimensional coordinates (z axis is perpendicular to the origin). Also in this case, the above-mentioned maslu 7c is shown as a fixed length maslu, and its arrangement position M03 is shown as "fixed".

FIG. 20 (b) shows the length L of the fixed length maslu 7c.
When M3 is fixed to the shortest length LMmin (LM3 = LMmi
n) Lengths of two movable massles 7a and 7b LM1 and LM
2 is the range of movement of the fingers 1-4 when the drive is controlled to the minimum length LMmin to the maximum length LMmax (angle αM in the bending direction)
Is indicated by the shaded area.

Explaining this further, when the length LM2 = LMmin of the maslu 7b (see the disposition position M02) and the length LM1 = LMmax of the maslu 7a (see the disposition position M01), the angle αM of the bending direction is α = π. In the direction, each bending θM becomes maximum (θMmax). Also, in this state, the length of the masle 7b LM2
By changing only, the angle αM of the bending direction is
The bending angle θM changes. When LM2 = LMmin, θ
M = 0.

Also, the length LM2 of the maslu 7b is set to the maximum length LMm.
When the length LM1 of the maslu 7a is changed in the state of ax (LM2 = LMmax), the angle αM of the bending direction of the fingers 1-4 is changed.
Is controlled in the direction of π to 4π / 3. When the length of the muscle 7a is LM1 = LMmax, the bending direction αM = 4π / 3, and the bending angle θM becomes maximum in this direction αM.

As described above, the length LM1 of the maslu 7a is changed to LMm with the length LM2 = LMmax of the maslu 7b.
When changing from ax to LMmin, the angle of the finger 1-4 in the bending direction is controlled within the range of αM = 4π / 3 to 5π / 3. Then, with LM1 = LMmin, αM = 5π / 3,
θM becomes the maximum value in the direction of αM at that time.
Thus, the length LM3 of the fixed length masle 7c is set to the shortest length LMm.
The moving range of fingers 1-4 when set to in is αM
= Π to 5π / 3.

21 (a), (b), and (c) show the finger 1-4 (finger tip portion) at the angle α M (horizontal axis) = π to 5π / 3 in the bending direction described above. The components indicating the other moving ranges of the central point M) are shown by white dots. Figure (a)
Shows the maximum value of the bending angle θMmax in the bending direction on the vertical axis. Further, in the same figure (b), the vertical axis shows the height Mz of the central point M at that time. And the same figure (c)
Indicates the component of the reference plane (the plane of z = 0) of the central point M at that time, that is, the horizontal distance “√ (Mx 2 + MY 2)” on the vertical axis.

The fingers 1-4 are the fixed-length maslu 7
When the length LM3 of c is set to the maximum length LMmax (LM3 =
LMmax), as shown by the slanted lines in FIG. 20 (c), the angle αM of the bending direction is controlled to move in the range of 0 to 2π / 3 centered on the π / 3 direction. The state of change of each component (θMmax, Mz, Mx and MY) in this movement control is
The direction of the range in which α M can take is only different from that in the case of FIG. 20 (b), and the other shows the same change state as in the case of FIG. 20 (b).

Further, the length of the fixed length maslu 7c is LM3 =
When (LMmax + LMmin) / 2, fingers 1-4
Although the control amount (range) as a whole of FIG.
As indicated by the diagonal lines in (d), the angle α M of the bending direction can be controlled in the range of 0 to 2π in all directions. 21 (a), (b),
In (c), components indicating other moving ranges of the center point M when the angle αM of the bending direction is 0 to 2π in all directions are shown by black dots. Figure (a) shows the maximum bending angle θMmax as
The figure (b) shows the height Mz, and the figure (c) shows the component "√ (Mx 2 + MY 2)" of the reference plane.

As described above, the two-massle drive type finger is effective when the range of movement control is narrow, and especially αM
When the range of π / 2 is π / 2, it is effective to increase the range of θM.

A single-mass drive type finger will be described as a fifth embodiment. FIG. 22 is a diagram showing the structure of a single-mass drive type finger of the fifth embodiment.
(a) is a partially cutaway perspective view of the drive unit, and (b) is a bottom sectional view thereof. Fingers 1--1 shown in FIGS.
5 is composed of one massle unit and two fixed length massles. In the muscle unit, the same parts as those shown in FIG. 3 are shown with the same numbers as in FIG.
In FIGS. 22 (a) and 22 (b), the massle driven by the massle unit is shown as the massle 7a, and the two fixed length massles are shown as the massles 7b and 7c.

Each of the masles 7a, 7b and 7c is made of a linear member having the same elastic force. Other configurations are similar to those of the first to third embodiments, and although not particularly shown,
A rotation sensor and a position sensor are arranged in the unit drive system. Further, the control circuit shown in the circuit block diagram of FIG. 12 is provided, and the fingers 1-5 are controlled based on the algorithm shown in the flowcharts of FIGS. That is, the control method is as follows:
It is sufficient to control the length of the maslu of the book. Further, the correction method may be performed for one driven massle, and the error detection method may be similarly performed by setting a limit range in advance. This finger 1-5 is also effective when the moving range of the finger tip portion is narrow, as described later.

FIGS. 23 (a), 23 (b) and 23 (c) are views for explaining the range of movement (movement of the tip) of the fingers 1-5 controlled in this way. The same figure (a) is similar to that shown in FIG. 7 (a), (b) or FIG. 8 (a), (b), and each masle 7 (7a, 7b, 7c), the arrangement positions M01, M02, and M03 are shown together with their circumscribing circles, and the finger tip center point M (Mx, My, Mz) is shown in three-dimensional coordinates (z axis is perpendicular to the origin). The above-mentioned masles 7b and 7c are shown as fixed length masles, and their arrangement positions M02 and M03 are shown as "fixed". The fingers 1-5 cannot move up and down, but can move in a certain range.

Now, if the fixed length masles 7b and 7c have the same length, that is, LM2 = LM3 = LC, then LM3−LM2 = 0 LM3 + LM2 = 2LC, from which θM = (4 / √3 · MR) (LC-LM1) .alpha.M = 0, (when LC.gtoreq.LM1) =. Pi., (When LC <LM1) IM = (MR / 2) (LM1 + 2LC). Also, Mx, My and Mz are expressed by the equation (4),
It is obtained from the equation (5) and the equation (6). This allows
It can be seen that αM is in one direction of “0” or “π” and θM is controlled by LM1. FIG. 23B shows the movement range of the fingers 1-5 at this time.

When the fixed length masles 7b and 7c have different lengths, that is, when LM2 = LC1 and LM3 = LC2, (LC1 ≠ LC2 and constant), LM3-LM2 = C3-2, (constant ) LM3 + LM2 = C3 + 2, (constant), and from now on

[0185]

(Equation 24)

[0186]

(Equation 25)

[0187]

(Equation 26)

Is obtained. Further, Mx, My and Mz are obtained from the equations (4), (5) and (6).
From this, it can be seen that the bending direction αM is controlled by LM1 while θM is substantially constant (the finger is bent at a substantially constant angle). FIG. 23C shows the movement range in the singer 1-5 at this time. The solid line indicates α M and the white dot indicates θ M.

As described above, when the control is performed in a narrow range such as when αM is controlled in one direction and θM is freely controlled, or when αM is controlled in a constant range in a state where the fingers are bent uniformly, the finger 1- 5 can be used.

[0190]

As described above, according to the present invention,
Since the controlled member can be freely moved only by changing the length of the masle of the linear member having elastic force, the movement control of the controlled member can be realized by controlling the advancing / retreating of the maslu. The mechanism is simplified, and it is possible to configure a manipulator that is small in size and capable of spatial motion over a wide range. Further, since the forward and backward movement of the massle is controlled by the screw shafts arranged in the gap between the drive sources in parallel with the drive sources, the space for disposing the drive mechanism is not wasted, so that a small manipulator can be constructed. Also, 3
Since the book massle is independently driven and controlled, the moving path, moving distance, and moving speed of the controlled member can be finely controlled, and thus a manipulator with high accuracy can be configured. Further, since the moving range of the controlled member is determined by the length of the masle, it is possible to increase the moving range of the controlled member by simply increasing the length of the masle. Thus, a manipulator having a large moving range can be easily provided.

Further, since the rotation of the screw shaft is controlled by using the sensor having the simple structure for detecting the rotation of the driving rotary shaft in synchronization with the rotation of the screw shaft, the amount of advance / retreat of the masle should be controlled with high accuracy. Therefore, it is possible to reliably control the manipulator even with a large change in load applied to the manipulator.
In addition, the position data and movement speed data of the controlled member are
Since the control is performed by converting the position data and the moving speed data of the masle controlled at the final stage of the drive mechanism, the high-speed moving control can be performed with a small amount of information that is easy to understand.

Further, since it always has the current position data of the massle, the movement control amount can be calculated from the current position data and the position data of the moving destination, and the control up to the moving destination can be immediately executed. Therefore, continuous movement can be controlled at high speed.

Further, since the position sensor capable of detecting the position of the masle at at least one part is used to periodically correct the absolute position data of the masle with respect to the reference plane,
Even if noise, power supply disconnection, or position displacement due to external force occurs during manipulator movement, the correct position of the manipulator can be maintained at all times, thus providing a highly accurate manipulator that can always continue normal operation. You can do it.

In addition, since the movement allowable range of the manipulator is held in advance as restriction data of the massle movement range for each processing and the restriction data and the control data are compared and confirmed before the control, incorrect control data is input. Even when the manipulator starts moving, it is possible to easily notify the error and move to an appropriate process corresponding to the error, and therefore, the wrong control data may adversely affect the peripheral device or the main device. Is eliminated.

Further, since the manipulator movement operation in a limited range can be obtained by reducing only one or two masle drive systems, the masle drive system can be adjusted according to the narrow range of manipulator movement control. Therefore, it is possible to provide a manipulator that is small, lightweight, and inexpensive, corresponding to the case where the control range of the moving operation is narrow, respectively.

[Brief description of drawings]

FIG. 1 is a perspective view showing a structure of a finger according to a first embodiment.

FIG. 2 is a bottom cross-sectional view of the finger of the first embodiment.

FIG. 3 is a perspective view showing a unit structure of the maslu of the first embodiment.

FIG. 4 (a) is a diagram showing a state in which the fingers are vertically moved,
(b) is a diagram showing a state of rotational movement of the fingers.

5A is an arrangement coordinate diagram of a masle, FIG. 5B is a coordinate development diagram of a finger, and FIG. 5C is a diagram showing a shape of a tip of the finger.

FIG. 6A is a change diagram of the length of each masulu controlled in accordance with the circular movement of the finger tip, and FIG. 6B is a circular orbit diagram of the finger tip.

7 (a) and 7 (b) are views for explaining that the bending maximum angles are different depending on the bending direction of the fingers.

FIG. 8A is a finger coefficient setting diagram, and FIG. 8B is a plan view of a masle.

FIG. 9 is a diagram illustrating bending deformation of fingers.

10 (a) and 10 (b) are diagrams showing an example of a finger in which bending deformation of a maslu is corrected.

FIG. 11 is a diagram showing an example of a rotation sensor.

FIG. 12 is a block diagram of a control circuit that controls a movement operation of fingers.

FIG. 13 is a flowchart of a process for controlling a movement operation of fingers.

FIG. 14 is a flowchart of a process for correcting a reference position of a masuru.

FIG. 15 is a flowchart of a process of determining a time to correct a reference position of a massle.

FIG. 16 is a flowchart of error processing when the finger movement is specified beyond the limit range.

FIG. 17 is a partially cutaway perspective view showing the structure of a finger in which a part of the motor housing and the guide plate of the second embodiment are integrated.

FIG. 18 is a partially cutaway perspective view showing the structure of a finger in which the motor housing and the case of the third embodiment are integrated.

FIG. 19 is a diagram showing the structure of a two-drive type finger of the fourth embodiment, in which (a) is a partially cutaway perspective view of a drive unit;
(b) is a bottom sectional view.

20 (a), (b), (c), and (d) are diagrams for explaining a movement control range of a finger of the two-mass drive type.

21 (a), (b), and (c) are graphs showing the movement control range of a two-massle drive type finger.

22A and 22B are views showing a structure of a single-massle drive type finger according to a fifth embodiment, wherein FIG. 22A is a partially cutaway perspective view of a drive portion, and FIG.

23 (a), (b), (c) are diagrams for explaining the operation control range of a single-drive type finger.

[Explanation of symbols]

1, 1-2, 1-3, 1-4 Fingers (manipulators) 2 Finger tips 3 Reference surface 4, 4-2 Guide plate (bearing plate) 5 Drive part 6 (6a, 6b, 6c) Guide hole for muscle 7 (7a, 7b, 7c) Muscle (muscle) 7k Virtual massle 7h Deformation massle 8 Case 9 Bearing plate 10 (10a, 10b, 10c) Motor 11 (11a, 11b, 11c) Screw shaft 12 (12a, 12b, 12c) Gear part 12-1 (12a-1, 12b-1, 12c-1) 1st gear 12-2 (12a-2, 12b-2, 12c-2) 2nd gear 12-3 (12a-3, 12b-3, 12c-3) Third gear 12-4 (12a-4, 12b-4, 12c-4) Fourth gear 13 (13a, 13b, 13c) Motor housing 13a ', 13b', 13c ' Motor housing 14 (14a, 14b, 14c) Slide screw nut 21 Circumscribing circle of the muscle arrangement 22 Correction coil spring 23 Regulation member 24 Motor rotation shaft 25 (25a, 25b, 25c) Rotation sensor 25-1 (25a-1, 25b- 1, 25c-1) Rotating arm / encoder 25-2 (25a-2, 25b-2, 25c-2) Photocoupler 26 Position sensor 31 CPU (central processing unit) 32 Program memory 33 Memory I 34 Memory II 35 memory III 36 motor driver 37 sensor amplifier 38 control input / output terminals 40a, 40b, 40c coreless motors 41a, 41b, 41c coreless motor shaft ends 42a, 42b, 42c bearing AB (AB1, AB2, AB3) reference position data for each masle AP (AP1, AP2, AP3) Present of each Masle Position data aM θmax Horizontal distance of finger tip when bending angle θM is maximum Ct1, Ct2, Ct3 Counter Ft Position of center vertex of finger tip Hr Radius of hemispherical part of finger tip Ht Finger tip Cylinder height IM Curvature radius of middle virtual masle Ikmin Radius of virtual masle k1 Rotation speed of screw shaft per unit distance of moving muscle LM (LM1, LM2, LM3) Length of muscle LMk Length of virtual masle LMc Central virtual masle length LMmax Maximum allowable length of muscle LMmin Minimum allowable length of muscle LMkmin Minimum length of virtual masle LMS (LMS1, LMS2, LMS3) Movement data in screw shaft speed unit LMSmin (LMS1min, LMS2min, LMS3min) Shortest movement limit data LMSmax (LMS1max, LMS2max, LMS3max) Longest movement limit data for muscles LMT (LMT1, LMT2, LMT3) Motor rotation Movement data in units of several units LMTmin (LMT1min, LMT2min, LMT3min) Shortest movement data for the muscle LMTmax (LMT1max, LMT2max, LMT3max) Longest movement data for the muscle M1, M2, M3 Fixed point on the bottom of the finger tip of the muscle M Finger Center point of the bottom of the tip M01, M02, M03 Arrangement position of the muscle on the reference plane MR Arrangement diameter of the muscle MS (MS1, MS2, MS3) Mass movement speed data M (Mx, My, Mz) Center of the bottom of the finger Coordinates of M (θM, αM, Mz) Coordinates of the center point of the bottom surface of the finger tip Mz Height of the center point of the bottom surface of the finger tip (distance from the reference plane) Mzθmax Height when the bending angle θM of the finger is maximum Mz S11 Latch of rotation sensor 25a S12 Latch of rotation sensor 25b S13 Latch of rotation sensor 25c S21 Latch of sensor 26a S22 position Latch of sensor 26b S23 Latch of position sensor 26c TM (TM1, TM2, TM3) Motor rotation speed from current position to control position Q Set time αM Angle of circular orbit of finger (angle in bending direction) θM Bending angle of finger (Bending angle) θMmax Maximum bending angle of finger ΔLMmax Maximum change length of muscle (LMmax-LMmin)

Claims (9)

[Claims] 1. A three-piece masle made of a linear member having bendable elasticity and arranged so as to form a ridge line of a triangular prism, and a controlled member to which one end of each of the masles is fixed, A guide plate having a guide hole which faces the controlled member with a reference surface facing the controlled member, and which has guide holes for inserting the three masles, respectively, and at least one guide plate disposed behind the reference surface of the guide plate. Drive means for moving the masle of the vehicle to and from the reference surface toward the controlled member side through the guide hole, and control means for controlling the drive operation of the drive means, wherein the drive means is a power source. A screw shaft rotatably in both forward and reverse directions by the power source and arranged in parallel to the advancing / retreating direction of the mastle; and screwing the screw shaft on one side and fixing the other end of the mastle on the other side. Screw shaft positive A manipulator, comprising: a screw nut member that moves forward and backward on the screw shaft in response to rotation in both reverse directions. 2. The driving means is provided for each of the masles, and the driving means drives the masles through the screw nut member by rotating the screw shaft in either forward or reverse directions, and the driving is performed. By the above Masuru,
2. The control member is advanced or retracted from the guide hole to move the controlled member to a desired position in all directions in the longest bending range of the mastle with respect to the reference surface.
The described manipulator. 3. Further comprising at least one position display means arranged on the drive rotation shaft of the power source, and a rotation sensor for detecting a sub-rotation of the position display means accompanying the rotation of the drive rotation shaft. And the control means controls the amount of advance / retreat of the masle by controlling the rotation of the screw shaft by the drive means based on the detection output of the rotation sensor to control the movement position of the controlled member. Claim 1 characterized by the above.
Or the manipulator described in 2. 4. The control means comprises position data consisting of x-coordinates, y-coordinates and z-coordinates representing a spatial position of the controlled member with respect to the reference plane, or position data consisting of a bending angle, a bending direction angle and a height. And finger speed data that represents the moving speed of the controlled member, and generates masulu position data and masuru moving speed data of the masuru corresponding to the movement destination of the controlled member from the position data and the finger speed data. 4. The manipulator according to claim 1, 2 or 3, wherein the controlled member is spatially moved based on the massle position data and the massle movement speed data. 5. The control member has a storage unit for storing the current position data of the massle, and updates the current position data stored in the storage unit every time the movement of the controlled member is controlled, Based on the current position data and the massle position data, a control rotation speed of the power source for controlling the advance / retreat of the massle from the current position to the destination position is generated, and the drive means of the drive means is generated based on the generated control rotation speed. The manipulator according to claim 1, 2, 3, or 4, which controls a driving operation. 6. A position sensor is further provided which is capable of detecting the position of the masle at least at one site, and the control means detects absolute position data of the position of the masuru detected by the position sensor with respect to the reference plane. 4. The movement of the controlled member is controlled via the drive means while correcting the movement of the controlled member based on the absolute position data of the held masle.
The manipulator according to 4 or 5. 7. The manipulator according to claim 6, wherein the control means updates the absolute position data of the massle when the position sensor detects the massle while controlling the forward and backward movement of the massle. . 8. The control means forcibly causes the position sensor to detect the maslu when a predetermined period elapses while controlling the forward / backward movement of the masuru to update the absolute position data of the masuru. The manipulator according to claim 6 or 7, characterized in that: 9. The control means retains masle movement amount restriction data preset corresponding to the permissible movement range of the controlled member, and the masle position data and the masle movement amount restriction data to be moved and set. And when the massle position data exceeds the massle movement amount limit data, error control is performed without performing movement control based on movement setting, and control is returned to an initial value. The manipulator according to claim 1, 2, 3, 4, 5, 6, 7, or 8.