JP2018114590A - Robot teaching device and robot teaching method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a robot teaching device which can easily teach an operation to a robot.SOLUTION: A robot teaching device 10 includes a sensor unit 11 which is mounted on a manipulator having an arm 106 and a hand 107 and has a proximity sensor 22, and an arithmetic unit 12 receiving a signal from the proximity sensor 22, where the arithmetic unit 12 calculates a movement direction of the manipulator away from a detection object when the proximity sensor 22 detects the detection object.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a robot teaching device and a robot teaching method.

  As a robot teaching method, an indirect teaching method in which an operator indirectly moves a robot arm using a remote operation tool and teaches its operation and an operator directly moves a robot arm to teach the operation. Direct teaching methods are known.

  In the indirect teaching method, for example, as shown in Patent Document 1, a button of a remote operation tool such as a teaching pendant is operated to move a robot arm to a predetermined position and store the series of operations.

On the other hand, in the direct teaching method, for example, as shown in Patent Document 2, an external force is applied to a robot arm to which a force sensor is attached, and the arm is moved in a direction in which a force is applied according to a force sensor signal. It moves to a predetermined position and memorizes the series of operations.
Moreover, as shown in Patent Document 3, there is also known a method of moving an arm with a sense close to teaching directly by attaching a joystick to the arm.

JP, 2006-185586, A JP-A-1-234185 Japanese Patent Laid-Open No. 10-202568

However, in the case of Patent Document 1, since it is necessary to match the operation direction centered on the operation panel and the direction centered on the robot or the robot arm, the position and orientation of the robot is changed by moving the robot. Depending on the situation, the operation direction may not be known. The operation is very complicated and requires skill.
In the case of Patent Document 2, if the sensitivity of the force sensor is increased too much, it reacts to fluctuations, vibrations, etc. of the robot. Yes. Therefore, considerable force is required for robot teaching. The burden is particularly large for large robots.
In the case of Patent Document 3, the arm can be moved with a feeling close to that of direct teaching. However, since the joystick is fixed to the arm, it is difficult to operate the joystick depending on the position or angle of the arm and the operation direction is not known. There is a case.
It is an object of the present invention to provide a robot teaching apparatus and a robot teaching method that can easily teach the operation of the robot.

  The robot teaching device of the present invention includes a plurality of proximity sensors attached to a manipulator and a calculation unit that receives a signal from the proximity sensor, and the calculation unit detects the detection object when the proximity sensor detects the detection object. The moving direction of the manipulator with respect to is calculated.

According to the robot teaching apparatus of the present invention, a plurality of proximity sensors detect a detection object, and a calculation unit calculates a moving direction of the manipulator with respect to the detection object. Can be moved freely. Further, since the movement of the manipulator can be operated centering on the proximity sensor (manipulator mounting portion), the operation is simple and the erroneous operation is unlikely to occur.
The robot teaching apparatus of the present invention is particularly preferable for teaching a vertical articulated arm type robot. The horizontal articulated robot can be moved with a relatively small force because the arm posture is maintained even if the servo motor is stopped and the holding force of the motor of each joint axis is moved. However, in the vertical articulated arm type robot, since the weight of the arm is applied to each joint, it is necessary to operate the servo motor in order to maintain the manipulator posture. The robot teaching apparatus of the present invention is highly effective when teaching a vertical articulated robot.

  In the robot teaching device of the present invention, it is preferable that the moving direction of the manipulator is a direction away from the detected object. In this case, since the distance between the detected object (for example, the operator's hand) and the manipulator (proximity sensor) can be maintained above a certain level, there is little risk to the operator even if a malfunction occurs in the robot device or the like.

  In the robot teaching apparatus according to the present invention, it is preferable that the proximity sensor has sensitivity to a living body. In this case, the operator's hand can be used as the detection object without using a conductor or the like as the detection object, and the teaching operation of the robot can be further simplified.

  In the robot teaching apparatus according to the present invention, it is preferable that at least two proximity sensors positioned one above the other are set as one set, and a plurality of sets are provided at equal intervals around the axis of the manipulator. By setting at least two proximity sensors positioned one above the other as a set, the vertical position of the detected object relative to the manipulator can be calculated. Then, by providing a plurality of sets in the circumferential direction of the manipulator, it is possible to calculate the front-rear and left-right positions of the detected object with respect to the manipulator. In particular, the calculation can be simplified by providing a plurality of sets at equal intervals in the circumferential direction of the manipulator.

  The robot teaching apparatus according to the present invention, wherein the plurality of proximity sensors are attached in a circumferential direction of an end effector of a manipulator, and the calculation unit is configured to detect a plurality of objects to be detected simultaneously by the plurality of proximity sensors and to move the manipulator. Is preferably calculated as the direction of rotation of the end effector. In this case, fine movement of the end effector can be taught. Here, “the movement direction of the manipulator cannot be calculated” means a state in which the movement direction of the manipulator with respect to each detected object is offset.

A robot teaching method of the present invention is a teaching method of a robot apparatus to which the robot teaching device of the present invention is attached, the step of moving a manipulator by moving a detected object close to a proximity sensor, and moving the detected object away from the proximity sensor. And a step of stopping the manipulator.
In such a robot teaching method, the step of moving the manipulator while bringing the detected object close to the proximity sensor moves the detected object closer to the proximity sensor opposite to the direction in which the manipulator is desired to move, and the manipulator is detected. A method that is a step of moving away from the object is preferable.

  A robot teaching method according to the present invention, wherein a robot teaching device according to the present invention is attached to which a calculation unit calculates a rotation direction of an end effector, and different proximity sensors are used so that the manipulator does not move a plurality of detected objects. Moving the plurality of detection objects simultaneously around the axis of the end effector in the direction in which the end effector is to be rotated, rotating the end effector, and moving the detection objects away from the proximity sensor. And a method of stopping the rotation of the end effector.

It is a whole lineblock diagram showing one embodiment of a robot teaching device of the present invention. 2a, 2b, and 2c are schematic views showing the operating state of the robot teaching apparatus of FIG. 1, respectively. It is a whole block diagram which shows one Embodiment of the robot apparatus which attached the robot teaching apparatus of FIG. 4a and 4b are flowcharts showing the operation procedure of robot teaching according to the present invention.

  A robot teaching apparatus 10 shown in FIG. 1 is attached to a manipulator, and includes a sensor unit 11 that is attached to the manipulator and includes a proximity sensor, and an arithmetic unit 12 that receives a signal from the sensor unit 11.

  As shown in FIG. 1, the sensor unit 11 includes a columnar main body 21 and a plurality of proximity sensors 22 provided on the surface thereof. For example, the sensor unit 11 is attached between an arm 106 and a hand (end effector) 107. The arm 106 rotates around its axis and pivots about the joint on the base side. Therefore, the sensor unit 11 moves or rotates together with the hand 107.

An upper engagement portion 21 a that engages with the arm 106 is provided on the upper surface of the main body 21, and a lower engagement portion 21 b that engages with the hand 107 is provided on the lower surface. In this embodiment, the upper engaging portion 21a has a cylindrical shape, and the engaging portion of the arm 106 is inserted and fixed. The lower engaging portion 21b has a columnar shape, and is inserted into and fixed to the engaging portion of the hand 107.
However, the fixing means for the main body 21, the arm 106 and the hand 107 is not particularly limited.
The shape of the main body 21 may be a column or a sphere having a regular polygonal cross section, and is not particularly limited. In particular, a cylinder or a sphere is preferable.

The proximity sensor 22 is connected to the calculation unit 12 by a cable 23 or the like. Then, the proximity sensor 22 sends a signal corresponding to the distance to the detected object to the calculation unit 12.
The plurality of proximity sensors 22 are arranged so as to be able to detect detection objects on the top, bottom, front, back, left and right. In this embodiment, two proximity sensors arranged one above the other are taken as a set, and the sets are arranged on the side surface of the columnar main body 21 at four locations at equal intervals in the circumferential direction (at intervals of 90 degrees from the central axis). Yes. Further, the main body 21 is arranged on the upper and lower surfaces of the main body 21 so as to be between the ones provided on the side surfaces in the circumferential direction, four at regular intervals in the circumferential direction (at intervals of 90 degrees from the central axis). Therefore, a total of 16 proximity sensors 22 are provided in the main body 21.
In this way, by setting the two proximity sensors 22 positioned above and below as one set, the vertical position of the detected object with respect to the sensor unit 11 can be calculated. In the embodiment, the two proximity sensors 22 are arranged in parallel with the axis of the main body 21, but they may not be in parallel. Then, by arranging the respective groups at equal intervals in the circumferential direction, the front and rear and left and right positions of the detected object with respect to the sensor unit 11 can be easily calculated. Therefore, the moving direction of the manipulator can be calculated. In particular, when the proximity sensors 22 are provided in the circumferential direction, the distance between each proximity sensor 22 and the axis of the main body 21 is the same, which is preferable. Furthermore, by providing the proximity sensor 22 on the upper surface and the lower surface of the main body 21, the detection accuracy in the upward or downward direction of the sensor unit 11 can be increased.
However, the arrangement of the proximity sensors 22 is not particularly limited. It is preferable that the detected object can be detected from all directions of up and down, front and rear, and left and right, but may be appropriately selected according to the specification of the robot.

As the proximity sensor 22, a known sensor such as a capacitance type, an induction type, an ultrasonic type, an electromagnetic wave type, or an infrared type is used. As such a proximity sensor 22, a sensor having sensitivity to a living body is preferable, and a sensor that detects a charge on the surface of the living body is particularly preferable. Thus, when it has sensitivity with respect to a living body, it is possible to teach a robot using an operator's hand as a detection object without using a glove with a metal piece or the like as the detection object.
As a proximity sensor having sensitivity to such a living body, for example, a capacitance type proximity sensor that detects a polarized charge of a dielectric can be cited. Further, a proximity sensor using a coiled carbon fiber dispersed in a base material made of a dielectric material, for example, a proximity sensor disclosed in JP 2007-201641 A can be cited.

When the proximity sensor 22 detects the detection object B, the calculation unit 12 calculates a direction in which the manipulator is away from the detection object B.
For example, as illustrated in FIG. 2A, when the detection object B is brought close to the sensor unit 11 and one proximity sensor 22 detects the detection object B, the calculation unit 12 is based on a signal from the proximity sensor 22. To calculate the vector Y1 heading toward the center of the sensor unit 11. The direction of the vector Y1 is the moving direction of the sensor unit 11 (manipulator).
In addition, as illustrated in FIG. 2B, when the detected object B is brought close to the sensor unit 11 and the two proximity sensors 22 detect the detected object B at the same time, the calculation unit 12 is based on the signals from the respective proximity sensors 22. Vectors Y1 and Y2 from the proximity sensors 22 toward the center of the sensor unit 11 are calculated. Then, the sum (vector Ys) of these vectors Y1 and Y2 is calculated. The direction of the vector Ys is the moving direction of the sensor unit 11 (manipulator). In FIG. 2 b, arcs A <b> 1 and A <b> 2 of imaginary lines represent detection areas of the proximity sensors 22.
When the robot teaching device 10 is mounted on a manipulator, the position information of the sensor unit 11 in the work space based on the position / posture of the manipulator is transmitted to the calculation unit 12, and the manipulator in the work space is determined according to the position information. To calculate the moving direction.

In addition, when the plurality of proximity sensors 22 are attached in the circumferential direction of the hand 107 and the plurality of proximity sensors 22 detect the plurality of detection objects B at the same time and the movement direction of the manipulator cannot be calculated, the computing unit 12 The directions of a plurality of detection objects that simultaneously rotate around are calculated as the rotation direction of the end effector.
For example, as shown in FIG. 2c, the two detection objects B are brought close to the sensor unit 11 with the sensor unit 11 interposed therebetween, and the two proximity sensors 22 facing each other across the shaft detect the detection object B, respectively. In this case, the calculation unit 12 calculates vectors Y1 and Y2 from the proximity sensors 22 toward the center of the sensor unit 11 based on the signals from the proximity sensors 22. The sum of these vectors Y1 and Y2 is zero (a direction vector of a predetermined amount or less may be set to zero). Therefore, the moving direction of the sensor unit 11 (manipulator) cannot be calculated. With the manipulator stopped in this manner, the two detection objects B are simultaneously rotated around the hand 107. In this case, the calculation unit 12 maintains a state in which the movement direction of the manipulator cannot be calculated and receives a signal indicating that the manipulator is away from the two proximity sensors 22, or thereafter, the calculation unit 12 and the two proximity sensors 22 A signal indicating that the detection object B has been detected is received from another adjacent proximity sensor 22a in the direction. The calculation unit 12 calculates the rotation direction of the detected object based on these signals.

Thus, since the calculating part 12 calculates the movement direction of a manipulator and the rotation direction of the end effector of a manipulator, it can move a manipulator freely.
The calculation unit 12 calculates the moving direction of the manipulator that moves away from the detected object, but the calculated direction is a direction having a predetermined angle with respect to the detected object, even if it is a direction approaching the detected object. Also good. By setting the distance away from the operator, the distance between the operator and the manipulator becomes a certain distance or more, so that the teaching work can be performed more safely. On the other hand, in the approaching direction, the manipulator to be operated can be operated more finely. In this case, it is preferable from the viewpoint of safety that the manipulator is stopped when the distance between the operator and the manipulator becomes a predetermined amount or less, or when the distance is in contact.
Further, the calculation unit 12 of this embodiment calculates the rotation direction of the end effector when the movement direction of the manipulator cannot be calculated. However, the calculation mode of the movement direction of the manipulator and the calculation of the rotation direction of the end effector are calculated. The mode may be selected and designated from the outside (for example, an external input device button).

  Since the robot teaching device 10 uses the sensor unit 11 using the proximity sensor 22, the manipulator to which the sensor unit 11 is attached can be moved simply by bringing the detected object close to the sensor unit 11, and the operator can Do not need. Further, since the detection object B is brought close to the sensor unit 11 attached to the manipulator to determine the moving direction of the manipulator, the operation is simple and an erroneous operation is unlikely to occur.

  Next, the robot apparatus 100 to which the robot teaching apparatus 10 is attached is shown in FIG. The robot apparatus 100 includes a base 101, a manipulator 102 extending from the base, and a control unit 103 that instructs the manipulator to move. The sensor unit 11 of the robot teaching device is attached to the manipulator 102, and the arithmetic unit 12 of the robot teaching device is incorporated into the control unit 103. The sensor unit 11 and the control unit 103 are connected by a cable or the like. Note that the arithmetic unit 12 of the robot teaching device may be connected as another device.

The manipulator 102 includes an articulated arm 106 and a hand (end effector) 107 provided at the tip thereof.
The multi-joint arm 106 includes a plurality of links 111 and joints (the turning joint 112a or the rotating joint 112b) that connect them. Further, the arm 106 and the base 101, and the arm 106 and the hand 107 are also connected by joints (the turning joint 112a and the rotating joint 112b).
Each joint includes an actuator (not shown) such as a servo motor and a sensor (not shown) for detecting the joint angle. The actuator and the sensor are connected to the control unit 103 by a cable or the like.
The articulated arm 106 is a known vertical articulated robot arm. However, various articulated robots such as a horizontal articulated type and a parallel link type may be used.

The sensor unit 11 is attached to a rotary joint 112 b between the arm 106 and the hand 107. Then, it moves or rotates integrally with the hand 107. As described above, the sensor unit 11 is preferably attached so as to be integrated with the hand 107. Thereby, the plurality of proximity sensors 22 are arranged substantially in the circumferential direction of the hand 107.
In addition, the attachment location of the sensor part 11 is not specifically limited. However, the robot is easier to operate on the tip side of the manipulator.

  The control unit 103 includes a calculation unit 12, a main calculation unit 103a, and a communication unit 103b. The control unit 103 is connected to a storage unit (not shown), an input device (not shown), and an output device (not shown). The storage unit stores the operation taught to the manipulator 102.

The main calculation unit 103a performs an arm position / posture calculation process based on the state of each joint (the turning joint 112a and the rotating joint 112b). The main calculation unit 103a also calculates the position and orientation of the sensor unit 11 at the same time.
The communication unit 103b transmits instructions necessary for movement of the arm 106 and the hand 107 to each joint based on the results of the main calculation unit 103a and the calculation unit 12. Also, an operator instruction input by the input device is transmitted.

Next, a robot teaching method will be described.
First, the teaching state of the robot apparatus 100 is started.
The operator's hand (detected object) is brought close to the sensor unit 11 and the manipulator 102 is moved (step S1A).
In step S <b> 1 </ b> A, when the sensor unit 11 detects the operator's hand, a signal is sent from the sensor unit 11 to the calculation unit 12 of the control unit 103. At the same time, the position information and posture information of the arm 106, the hand 107, and the sensor unit 11 at that time are sent to the calculation unit 12 from the main calculation unit 103a. Then, the moving direction of the manipulator 102 is calculated by the calculation unit 12. Based on the result of the calculation unit 12, the communication unit 103b instructs each actuator to operate, and the manipulator 102 starts to move. It should be noted that the operator's hand is brought closer to the sensor unit 11 on the opposite side to the direction in which the operator's hand is desired to be moved, that is, the operator's hand is brought closer to the proximity sensor 22 on the opposite side to the direction to be moved. It is preferable to move it away from it.
At the same time when the manipulator 102 arrives at a predetermined position, the operator's hand is moved away from the sensor unit 11 to end the movement of the manipulator 102 (step S2A).
When it is desired to bend the path of the manipulator 102, the operator's hand is moved away from the sensor unit 11 at the position to be bent, and the process returns to step S1A.

Next, a method for rotating the hand 107 around the axis of the hand 107 will be described.
The operator's hands (two detected objects) are brought closer to the sensor unit 11 with the sensor unit 11 interposed therebetween, that is, the respective hands are brought closer to the two proximity sensors 22 on the opposite side of the sensor unit 11 (step S1B). ).
In step S <b> 1 </ b> B, the sensor unit 11 simultaneously detects both hands of the operator, so that a signal is sent from the sensor unit 11 to the calculation unit 12 of the control unit 103. The calculation unit 12 cannot calculate the moving direction, and the arm 106 and the hand 107 remain in place.
The operator's hands are rotated around the sensor unit 11 in the direction in which the hand 107 is to be rotated, and the hand 107 is rotated (step S2B).
In step S2B, the sensor unit 11 detects the rotation of both hands of the operator, and the calculation unit 12 calculates the rotation direction of both hands of the operator. Based on the result of the calculation unit 12, the communication unit 103b instructs the actuator of the hand 107 to rotate, and the hand 107 rotates.
At the same time as the hand 107 is in a predetermined posture, both hands of the operator are moved away from the sensor unit 11, and the rotation of the hand 107 is ended (step S3B).

This teaching method of the robot apparatus can move the arm to any position and posture without touching the robot at all.
In the above method, the operator's hand is cited as the detection object, but the detection object is not particularly limited. A highly sensitive detection object may be used according to the proximity sensor to be used.

B Detected object 10 Robot teaching device 11 Sensor unit 12 Calculation unit 21 Main body 21a Arm engagement unit 21b Hand engagement unit 22 Proximity sensor 23 Cable 100 Robotic device 101 Base 102 Manipulator 103 Control unit 103a Main calculation unit 103b Communication unit 106 Multi-joint Arm 107 hand (end effector)
111 link 112a swing joint 112b rotary joint

Claims (8)

A plurality of proximity sensors attached to the manipulator of the robot, and an arithmetic unit that receives signals from the proximity sensors;
The calculation unit calculates a moving direction of the manipulator with respect to the detected object when the proximity sensor detects the detected object.
Robot teaching device. The moving direction of the manipulator is a direction away from the detected object.
The robot teaching apparatus according to claim 1. The proximity sensor is sensitive to a living body.
The robot teaching apparatus according to claim 1 or 2. A set of at least two proximity sensors positioned above and below each other, and a plurality of sets are provided at equal intervals in the circumferential direction of the manipulator.
The robot teaching apparatus according to any one of claims 1 to 3. The plurality of proximity sensors are attached in the circumferential direction of the end effector of the manipulator,
When the plurality of proximity sensors detect a plurality of detected objects at the same time and the moving direction of the manipulator cannot be calculated, the calculation unit determines the direction of the plurality of detected objects that rotate simultaneously around the end effector in the rotation direction of the end effector. Calculate as
The robot teaching apparatus according to any one of claims 1 to 4. A robot teaching method equipped with the robot teaching device according to claim 1,
Moving the manipulator close to the proximity sensor; and
A step of moving the detected object away from the proximity sensor and stopping the manipulator.
Robot teaching method. The step of moving the manipulator with the detection object close to the proximity sensor is a step of moving the detection object close to the proximity sensor opposite to the direction in which the manipulator is to be moved and moving the manipulator in a direction away from the detection object.
The robot teaching method according to claim 6. A robot teaching method comprising a robot teaching device according to claim 5 and a manipulator attached thereto,
Bringing a plurality of detection objects close to different proximity sensors so that the manipulator does not move;
Simultaneously rotating a plurality of detection objects around the end effector in a direction in which the end effector is to be rotated, and rotating the end effector;
A step of moving the plurality of detection objects away from a proximity sensor and stopping the rotation of the end effector.
The robot teaching method according to claim 6 or 7.

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