JPH0623685A - Automatic positioning device - Google Patents

Abstract

PURPOSE:To provide an automatic positioning device which varies the positions and the angles of a plurality of non-contact displacement sensors to measure a distance to an object, in an automatic positioning device for a robot manipulator. CONSTITUTION:In a robot, an object is grasped by a finger part 1 and the finger part 1 is supported by a hand part 2 having articulated structure. The finger part 1 is provided with a plurality of displacement sensors 3 and a hand part 2 is controlled by the displacement sensors 3 so that outputs by means of which a distance to an object to be worked is measured are made equal to each other In this case, a displacement sensor drive mechanism 4 to change the position or the angle of one or all of the displacement sensors 3 is provided. The position or the angle of the displacement sensor 3 is made changeable according to the shape of the object to be worked.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic positioning device for a robot manipulator, and more particularly to an automatic positioning device having a plurality of non-contact displacement sensors whose position and angle are variable.

In recent years, work robots have been widely used. In the work robot, it is necessary to position the object in a predetermined positional relationship with respect to the work target. When the coordinate value of the work object is unknown, it is less accurate to perform the positioning visually,
In addition, since it requires a long time, an automatic positioning device for automatically positioning has come to be used.

In such an automatic positioning device,
It is desirable to be able to change the position and angle of a plurality of non-contact displacement sensors for positioning according to the shape of the work object.

[0004]

2. Description of the Related Art FIG. 7 shows a robot having an automatic positioning device, which is a 6-axis articulated robot, 11 is a finger portion for gripping an object, and 12 is a finger portion 11. Hand part, 13 is finger part 1
It is a finger provided at the tip of 1. Reference numeral 14 denotes a plurality of displacement sensors, and 15 is a work target.

The hand portion 12 has a 6-axis articulated structure,
It supports the finger portion 11 at the tip. Finger part 11
Grips an object with the finger 13 provided at its tip, and measures the distance from the work target 15 with the displacement sensor 14. As a result, the hand unit 12
Drives the 6-axis articulated structure to move the object gripped by the finger portion 11 to a desired positional relationship with respect to the work target 15. The target position of the finger portion 11 with respect to the work target 15 is a position where the distances from the work target 15 in the plurality of displacement sensors 14 are equal to each other.

Each of the displacement sensors 14 is, for example, a laser non-contact displacement sensor, but may be an ultrasonic sensor or the like. The distance measurement output from each displacement sensor 14 is converted from analog to digital (A / D), and the digitized output is added to a computer (not shown) to perform the required calculation.
The hand unit 12 is driven according to the result.

The robot has a program for driving the hand portion 12 to move the finger portion 11 so that the measured outputs from the respective displacement sensors 14 are always equal.
As a result, the object gripped by the finger portion 11 is controlled so as to be perpendicular to the work target 15 and have a predetermined distance.

FIGS. 8A and 8B show an example of the structure of a conventional finger portion, in which FIG. 8A is a top view, FIG. 8B is a side view, 20 is a shaft at the tip of the hand portion, 211 _, 21 ₂ is a finger for gripping an object, 22 _1, 22 ₂ are guides for moving the fingers 21 _1, 21 _{2 ,} respectively, 23 is an object, 2
Reference numeral 4 is a frame, and 25 _1, 25 _2, 25 ₃ are displacement sensors for measuring the distance to the surface of the work target.

The finger portion 11 is a portion of the frame 24, and is fixed to the shaft 20 at the tip of the hand portion 12. The fingers 21 _1, 21 ₂ move along the guides 22 _1, 22 ₂ fixed to the frame 24,
Hold the object 23 in the middle. Displacement sensor 25 _1, 25
_2, 25 ₃ are installed on the frame 24, for example, concentrically at intervals of 120 °, and each outputs a measurement by measuring the distance from the surface of the work target.

Therefore, each displacement sensor 25 _1, 25 _2, 25 ₃
So that the output from each of them becomes a predetermined equal value.
By driving 2, the object 23 gripped by the fingers 21 _1, 21 ₂ can be held at a predetermined distance vertically to the work object.

[0011]

In the finger portion 11, the displacement sensors 25 _1, 25 _{2 and} 25 ₃ are fixedly attached, and their positions and angles cannot be changed. Therefore, it is necessary that the surface of the work object whose distance is to be measured by each displacement sensor 25 _1, 25 _2, 25 ₃ is a flat surface having a certain width.

Therefore, in the conventional automatic positioning device,
Due to the structure, the measurable shape of the work object is limited, and there is a problem that the object cannot be held in a desired positional relationship when the work object has an arbitrary shape.

SUMMARY OF THE INVENTION The present invention is intended to solve the problems of the prior art, and it is an object of the present invention to enable an automatic positioning apparatus to position an object regardless of the shape of the work object. I am trying.

[0014]

FIG. 1 shows the basic configuration of the present invention. According to the present invention, the finger part 1 for gripping an object is supported by the hand part 2 having an articulated structure, and the finger part 1 has a plurality of displacement sensors 3, and each of the displacement sensors 3 is connected to a work object. In a robot that controls the hand unit 2 so that the outputs of which distances are measured are equal, a displacement sensor drive mechanism 4 that changes the position or angle of one or more or all of the displacement sensors 3 is provided, and The feature is that the position or angle of the displacement sensor 3 can be changed according to the shape.

According to the present invention, at this time, the displacement sensor drive mechanism 4 is used.
However, the plurality of displacement sensors 3 are rotatably supported via fulcrums 27 provided on the base 26 of the finger portion 1, and the cams 2 are provided on the opposite side of the fulcrums 26 of the displacement sensors 3.
9 is provided, and by moving the cam seat 30 that simultaneously engages with the cam 29 of each displacement sensor 3, each displacement sensor 3
It is characterized by simultaneously changing the angle of.

Further, according to the present invention, the displacement sensor drive mechanism 4 is
Mount one or more displacement sensors 3 on both ends of the finger base 2
Attached to the displacement sensor support plate 35 _{1-35 3} rotatably supported on a support table provided in the 6, by rotating the shaft of the displacement sensor support plate, intended for changing the angle of the displacement sensor 3 It is characterized by being.

Further, in the present invention, the displacement sensor drive mechanism 4 is
A rack 41 is attached to one or more displacement sensors 3, and a pinion 42 that meshes with the rack 41 is rotated to linearly move the displacement sensor 3 in parallel with the base 26 of the finger portion. To do.

Further, according to the present invention, the displacement sensor drive mechanism 4 is
The one or more displacement sensors 3 are axially supported by the arm 45 perpendicularly to the base 26 of the finger portion, and the gear 46 provided on this shaft is rotated via the pinion 47, whereby the displacement sensor 3 Parallel to the base 26 of the fingers,
It is characterized by being rotated and moved.

[0019]

The robot supports the finger portion 1 with the hand portion 2 having an articulated structure, grips an object with the finger portion 1, and uses a plurality of displacement sensors 3 provided on the finger portion 1 to move the work object The distance is measured and the hand unit 2 is controlled so that the outputs become equal.
In this case, by providing the displacement sensor drive mechanism 4 and changing the position or angle of one or more or all of the displacement sensors 3, the position or angle of the displacement sensor 3 is changed according to the shape of the work object. Change.

At this time, the plurality of displacement sensors 3 are rotatably supported via fulcrums 27 provided on the base 26 of the finger portion 1, and cams are provided on the opposite side of the fulcrums 26 of the displacement sensors 3. 29 is provided. And each displacement sensor 3
The displacement sensor drive mechanism 4 is configured so that the angles of the displacement sensors 3 are simultaneously changed by moving the cam seats 30 that simultaneously engage the cams 29 of FIG.

At this time, one or more displacement sensors 3 are
Attached to the displacement sensor support plate 35 _{1-35 3} is rotatably supported at both ends of the displacement sensor support plate a support table provided in the base 26 of the finger portion. Then, the displacement sensor driving mechanism 4 is configured so that the angle of the displacement sensor 3 is changed by rotating the shaft of the displacement sensor support plate.

At this time, the rack 41 is attached to one or more displacement sensors 3. And this rack 4
By rotating the pinion 42 that meshes with 1,
The displacement sensor drive mechanism 4 is configured to linearly move the displacement sensor 3 in parallel with the base 26 of the finger portion.

At this time, one or more displacement sensors 3 are
The arm 45 is vertically supported with respect to the base 26 of the finger portion. The displacement sensor drive mechanism 4 is configured so that the gear 46 provided on this shaft is rotated via the pinion 47 to rotationally move the displacement sensor 3 in parallel to the base 26 of the finger portion.

Therefore, according to the present invention, when the distance to the work object is measured using the displacement sensor and the robot is positioned, the position and attachment of each displacement sensor are determined according to the shape of the work object. By changing the angle, it is possible to automatically position the object with respect to the work object having an arbitrary shape.

[0025]

FIG. 2 shows an embodiment of the present invention in which the inclinations of a plurality of displacement sensors are changed at the same time. FIG. 2A is a top view and FIG. The AA arrow line view is shown. The same parts as those in FIG. 8 are shown by the same numbers, and the detailed structure is shown for the displacement sensor 25 ₂ , but the same applies to the other displacement sensors 25 _1, 25 ₃ . Reference numeral 26 indicates a base of the finger portion, 27 is a fulcrum of a displacement sensor 25 ₂ provided on the base 26, 28 is a spring that applies a rotational force in a constant direction to the displacement sensor 25 ₂ , 29 is a cam, and 30 is a cam 29. A cam seat engaging with, 31 is a spindle, 32 is a speed reducer for rotating the spindle 31, 33
Is a motor.

The fingers 21 _1, 21 ₂ are guides 22 _1, 22.
_By moving along ₂ , the object 23 is gripped in the middle. The displacement sensors 25 _1, 25 _{2 and} 25 ₃ are the base 2
6 are installed, for example, on concentric circles at intervals of 120 °, and the distances to the surface of the work target are measured and outputs are generated.

[0027] At this time, the displacement sensor 25 ₂ is pivotally supported at a fulcrum 27 provided to the lower part to the base 26 by a spring 28 constantly undergoing a rotational force of a predetermined direction relative to the base 26 . A cam 29 is provided at an extension of the displacement sensor 25 ₂ with respect to the fulcrum 27, and the cam seat 3
0 is engaged.

The cam seat 30 is screwed on the spindle 31.
The spindle 31 is connected to the motor 3 via the speed reducer 32.
It is configured to rotate by 3. Therefore,
Driven by the motor 33 to raise or lower the cam seat 30.
Displacement sensor 25 when descending ₂Is centered around the fulcrum 27
It is configured to rotate and tilt at an angle. Other strange
Position sensor 25_1,25₃Is also the same.

FIG. 3 shows a state in which the displacement sensor is tilted.
The same as in Fig. 2 with the same number
is doing. That is, depending on the rotation of the spindle 31,
The cam seat 30 descends, which moves the cam 29 to the outside.
Because it moves, the displacement sensor 25 ₂Inward in the range of 15 °
It has been shown to lean. Also, other displacement cells not shown
Sensor 25_1,25₃Similarly, as the cam seat 30 descends,
Tilts inward within a 15 ° range.

Each displacement sensor 25_1,25_2,25₃Is
Tilt within the range does not change the distance measurement ability.
In the embodiment shown in FIGS. 2 and 3, each displacement sensor 25_1,
25 _2,25₃From the vertical state, tilt inward synchronously.
And the distance measurement by each displacement sensor.
The surface of the work object becomes narrow. For example all displacement sensors
However, when tilted inward by 15 ° from the vertical,
Position in a measuring area that is 30% wide
You can

In the embodiment shown in FIG. 2, each displacement sensor can be tilted outward. When the object has a wide flat surface, positioning can be performed with higher accuracy by orienting the displacement sensors outward.

FIG. 4 shows another embodiment of the present invention, showing another example in which the inclination of one or more of a plurality of displacement sensors is changed. Top view,
(B) has shown the side view. The same parts as those in FIG. 2 are indicated by the same numbers, 35 _1, 35 _2, 35 ₃ are displacement sensor support plates, and 36 _1, 36 _2, 36 ₃ and 37 _1, 37 _2, 37 ₃ are displacement sensor support plates 35 _{1 ,} 35 _2, 35 ₃ are supported at both ends, 38 _1, 38 _2, 38 ₃ are reduction gears, 39 _1, 39 _2, 3
9 ₃ is a motor.

For example, the displacement sensor 25 ₂ is fixedly supported by the displacement sensor support plate 35 ₂ . The displacement sensor support plate 35 ₂ is rotatably supported by support bases 36 _{2 and} 37 ₂ having shafts at both ends fixed to the base 26, and one end of the shaft is coupled to the speed reducer 38 _2. There is.
Reduction gear 38 ₂ being coupled to the motor 39 _2, with the rotation of the motor 39 _2, rotates the displacement sensor support plate 35 _2. The other displacement sensor support plates 35 _{1 and} 35 ₃ are also the same, and rotate as the motors 39 _{1 and} 39 ₃ rotate.

Therefore, each displacement sensor 25 _1, 25 _2, 25 ₃
Can be tilted at a certain angle from the vertical state, so that the width of the surface of the work object whose distance is measured by each displacement sensor 25 _1, 25 _2, 25 ₃ can be changed.

FIG. 5 shows still another embodiment of the present invention, in which one or more positions of the plurality of displacement sensors are changed in the radial direction perpendicular to the central axis of the finger portion. The case is shown. The same components as those in FIG. 2 are indicated by the same numbers, and the detailed structure of the displacement sensor 25 ₂ is shown, but the same applies to the other displacement sensors 25 _{1 and} 25 ₃ . Reference numeral 40 denotes a lower substrate provided in parallel with the lower portion of the base 26. 41 is a rack fixed to the lower part of the displacement sensor 25 ₂ , 42 is a pinion provided so as to mesh with the rack 41, 43 is a linear slider for moving the rack 41 in the radial direction parallel to the surface of the lower substrate 40, and 44 is It is a motor that rotates the pinion 42.

A motor 44 rotates the pinion 42.
Then, the linear slider 43 causes the rack 41 to move to the base.
Since it moves in the radial direction along the surface of the plate 40, the displacement sensor
25 ₂The position of also changes in the radial direction. Other displacement sensor 25
_1,25₃Similarly, the position of changes in the radial direction. Therefore,
Each displacement sensor 25_1,25_2,25₃Measured by
The size of the work surface can be changed.
It

FIG. 6 shows still another embodiment of the present invention, in which one or more of the plurality of displacement sensors are rotated about an axis provided perpendicularly to the substrate. The case where the position is changed is shown. The same components as those in FIG. 2 are indicated by the same numbers, and the detailed structure of the displacement sensor 25 ₂ is shown, but the same applies to the other displacement sensors 25 _{1 and} 25 ₃ . Reference numeral 45 is an arm that supports the displacement sensor 25 ₂ , 46 is a gear attached to the base of the arm 45, and 47 is a gear 4
6 is a pinion that meshes with 6, and 48 is a motor that rotates the pinion 47. Each of these parts is provided on the lower substrate 40 below the base 26, and the gear 46 is provided on the lower substrate 40.
Is supported perpendicular to the plane of. Other displacement sensors 25 _1, 2
The same applies to 5 ₃ .

The pinion 47 is rotated by the motor 48.
Then, as the gear 46 rotates, the arm 45 displaces.
Service 25₂Rotate while keeping vertical. Other displacement sensor
25 _1,25₃Similarly, the arms that support the
Rotate around the position of a. Therefore, each displacement sensor
25_1,25_2,25₃Work object whose distance is measured by
The size of the surface of the object changes.

[0039]

As described above, according to the present invention, when the robot is positioned by measuring the distance to the work object using the displacement sensor, the positioning is performed according to the shape of the work object. Since it is possible to change the position or the angle of the plurality of displacement sensors for use in the work, it is possible to automatically position the object with respect to the work object having a surface having an arbitrary width.

[Brief description of drawings]

FIG. 1 is a diagram showing a principle configuration of the present invention.

2A and 2B are views showing an embodiment of the present invention, in which FIG. 2A is a top view and FIG.

FIG. 3 is a diagram showing a state in which a displacement sensor is tilted.

FIG. 4 is a diagram showing another embodiment of the present invention, in which FIG.
Shows a top view, and (b) shows a side view.

FIG. 5 is a diagram showing still another embodiment of the present invention.

FIG. 6 is a diagram showing still another embodiment of the present invention.

FIG. 7 is a diagram showing a robot having an automatic positioning device.

FIG. 8 is a diagram showing a configuration example of a conventional finger portion,
(A) shows a top view and (b) shows a side view.

[Explanation of symbols]

1 Finger part 2 Hand part 3 Displacement sensor 4 Displacement sensor drive mechanism 26 Base 27 Support point 29 Cam 30 Cam seat 35 _{1 to} 35 ₃ Displacement sensor support plate 41 Rack 42 Pinion 45 Arm 46 Gear 47 Pinion

Claims (5)

[Claims] 1. Finger part (1) for gripping an object
Is supported by a hand part (2) having an articulated structure, and the finger part (1) has a plurality of displacement sensors (3), and each displacement sensor (3) measures a distance to a work object. In the robot that controls the hand unit (2) so that the output is equal, a displacement sensor drive mechanism (4) that changes the position or angle of one or more or all of the displacement sensors (3) is provided. The automatic positioning device is characterized in that the position or angle of the displacement sensor (3) can be changed according to the shape of the work object. 2. The displacement sensor driving mechanism (4) includes a plurality of displacement sensors (3) for mounting a base (2) of the finger portion (1).
The fulcrum (26) of each displacement sensor (3) is rotatably supported via a fulcrum (27) provided at 6).
A cam seat (30) that is provided with a cam (29) on the opposite side to and simultaneously engages with the cam (29) of each displacement sensor (3).
The automatic positioning device according to claim 1, wherein the angle of each displacement sensor (3) is simultaneously changed by moving the. 3. The displacement sensor drive mechanism (4) rotatably supports one or more displacement sensors (3) at both ends on a support base provided on a base (26) of the finger portion. attached to the displacement sensor support plate (35 ₁ to 35 _3), according to claim 1, by rotating the shaft of the displacement sensor support plate, and characterized in that changing the angle of the displacement sensor (3) The automatic positioning device described in. 4. The displacement sensor drive mechanism (4) attaches a rack (41) to one or more displacement sensors (3) and rotates a pinion (42) meshing with the rack (41). The automatic positioning device according to claim 1, wherein the displacement sensor (3) is linearly moved in parallel with the base (26) of the finger portion. 5. The displacement sensor driving mechanism (4) axially supports one or more displacement sensors (3) perpendicularly to a base (26) of the finger portion via an arm (45), By rotating a gear (46) provided on the shaft via a pinion (47), the displacement sensor (3) is rotationally moved in parallel with the base (26) of the finger portion. The automatic positioning device according to claim 1, which is characterized in that: