JPH05301182A - Direct teaching device of robot - Google Patents

Abstract

PURPOSE:To provide a direct teaching device which can obtain a teaching data from the general position by non-contact and simple operation, can reduce the time necessary for the teaching work, and can improve the efficiency of the teaching work, of a robot. CONSTITUTION:A range sensor 5 which can obtain the data as to the distance to a work 6 and the form of the work 6 in a non-contact way is provided to the wrist 3 of a manipulator 1. In a teaching data operation member 9, the absolute coordinates of the observation point on the work 6 is found depending on the data of the position and the posture of the wrist 3, and the data obtained by the range sensor 5, and it is made into teaching data.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a direct teaching device for a robot, and more particularly to a direct teaching device capable of acquiring teaching data without contact with an object.

[0002]

2. Description of the Related Art Teaching methods for a robot include a teaching pendant method and a direct teaching method.
In the method using the teaching pendant, the teaching pendant is attached to the robot, and the effector is attached to the wrist portion (wrist portion) of the manipulator portion of the robot. The teaching operator operates the teaching pendant to position the effector at a desired teaching point on the work (work target), and stores the position and orientation of the manipulator at the teaching point in the manipulator control device or the like. The teaching is completed by performing such positioning and storage operations for all required teaching points.

On the other hand, the direct teaching method is a method using force control. In this method, a force sensor is attached to the wrist section of the manipulator in addition to the effector, and the force control control means moves the manipulator in the direction in which the force is applied according to the output of the force sensor. ing. The teaching operator positions the effector of the manipulator at a desired teaching point by applying force to the effector, and stores the position and orientation in the control means or the like to perform the teaching.

[0004]

In the teaching method using the teaching pendant described above, each teaching point is read and stored, so that the number of teaching points becomes enormous with respect to a work having a complicated shape. Since it is necessary to teach the position and orientation at the teaching point of No. 3, there is a disadvantage that a great deal of time and labor is required.
Further, in this teaching method, since the manipulator is operated by using the teaching pendant, a considerable degree of skill is required to move the effector to a desired teaching point and accurately perform positioning at a desired position or posture. Will be needed.

The direct teaching method is a method in which the teaching operator actually holds the tip of the effector and positions it at a desired teaching point, but in order to obtain all the teaching points while positioning the tip of the effector with high accuracy. As with the method using the teaching pendant, there is a problem that skill is required.

An object of the present invention is to provide a robot capable of acquiring teaching data from a rough position by a non-contact and simple operation, shortening the time required for teaching work, and improving the efficiency of teaching work. It is to provide a direct teaching device.

[0007]

A robot direct teaching apparatus according to a first aspect of the present invention comprises a distance measuring means which is attached to a wrist portion of a manipulator of the robot and measures a distance to a target point on an object without contact. Data processing means for calculating the absolute position of the point of interest from the data relating to the position of the wrist portion and the distance data measured by the distance measuring means, and using the absolute position as teaching data for the point of interest.

A direct teaching device for a robot according to the second invention is
Attached to the wrist section of the robot manipulator,
The object from a visual sensor that acquires data on the shape of the object and data on the distance to the object, data on the position and orientation of the wrist portion, and data on the shape and distance obtained by the visual sensor. There is provided a data calculation means for calculating the absolute position of the upper point of interest and using the absolute position as teaching data for the point of interest.

[0009]

Function: Distance measuring means for measuring the distance to the object in a non-contact manner, and data calculation means for calculating the absolute position of the point of interest from the position of the manipulator and the distance data measured by the distance measuring means to obtain teaching data. Since it has, the teaching can be performed without accurately positioning the hand of the manipulator, and the efficiency of the teaching work is improved. In this case, a visual sensor is used as the distance measuring means, and a sensor data discriminating means for discriminating a characteristic shape to be noticed from the shape data observed by the visual sensor and discriminating it as a point of interest is provided and extracted by the sensor data discriminating means. By sequentially calculating the absolute position of the point of interest while tracking the determined point of interest, the route teaching data can be easily obtained only by moving the manipulator along the target route.

[0010]

Embodiments of the present invention will now be described with reference to the drawings. FIG. 1 is a diagram for explaining the configuration of a robot system including a robot direct teaching device according to an embodiment of the present invention, and FIG. 2 is a block diagram showing a specific configuration of a controller.

The manipulator 1 is of a multi-joint type composed of a plurality of arms 2. By moving the joint between the arms 2, the manipulator 1 can be moved to a desired position. It has become. The object to be taught by this robot is the work 6. A 6-axis force sensor 4 and a range sensor 5 are attached to a wrist (wrist) portion 3 located at the extreme end of the series of arms 2. The force sensor 4 detects the force and the moment applied to the wrist unit 3 for each component in each direction. The range sensor 5 can measure the shape of an object such as the work 6 without contact, and in this case, the distance from the range sensor 5 to the work 6 can also be obtained. Therefore, the coordinates of each point forming the work 6 can be described with reference to the coordinate system of the range sensor 5. As the range sensor 5,
For example, one using a range finder can be used.

A controller 7 for controlling the manipulator 1 is also provided. This controller 7
Is roughly divided into a control unit 8 for freely operating the manipulator 1, a position / orientation of the wrist unit 3 (that is, the hand of the manipulator 1), and a desired teaching point calculated from data obtained from the range sensor 5. The teaching data calculation unit 9 and the teaching data calculation unit 9 are provided. Here, the controller 7 will be described in more detail.

Since the force sensor 4 is provided in the wrist portion 3, the manipulator 1 can be subjected to force control. The control unit 8 performs force control for freely operating the manipulator 1, and detects the position and orientation of the wrist unit 3. Since the length of each arm 2 is generally fixed and the rotation angle of each joint is known to the control unit 8, the control unit 8 can easily know the position and posture of the wrist unit 3. The control unit 8 includes a force detection unit 10 that receives a signal from the force sensor 4, and a coordinate conversion unit 11 that smoothly moves the wrist unit 3 in the direction in which the force is applied based on the magnitude and direction of the detected force. And a position detection unit 12 that detects the position and orientation of the wrist unit 3.
In the coordinate conversion unit 11, based on a preset arithmetic expression,
The parameters required for force control are calculated.

On the other hand, the teaching data calculation unit 9 performs preprocessing such as noise removal on the raw data from the synchronization signal generation unit 13 and the range sensor 5 for establishing the synchronization between the control unit 8 and the teaching data calculation unit 9. The sensor data processing unit 14 to be executed, the sensor data determination unit 16 for processing the data from the sensor data processing unit 14 to extract and determine a characteristic shape to be noticed, and the processing result in the sensor data determination unit 16. Sensor data display unit 1 which is a monitor for displaying an image
5, the position storage unit 18 that temporarily stores the position and orientation detected by the position detection unit 12 of the control unit 8, the processing result of the sensor data determination unit 16 and the stored contents of the position storage unit 18 An absolute position calculation unit 17 that obtains absolute position and uses it as teaching data, and a teaching data storage unit 19 that stores the teaching data calculated by the absolute position calculation unit 17.

Next, the operation of this embodiment will be described with reference to FIG. The teaching handle 20 is attached to the hand of the manipulator 1.

In order to teach the work 6 as a target, the teaching operator operates the teaching handle 20 so as to bring the hand of the manipulator 1 close to the position to be taught. Since the force sensor 4 is attached to the wrist unit 3, the control unit 8 drives the manipulator 1 in accordance with the force applied to the teaching grip 20 by the teaching operator, and the wrist unit 3 is located near the position where the teaching is to be performed. You will get closer.

The position and orientation of the wrist section 3 are detected by the position detection section 12 based on the synchronization signal from the synchronization signal generation section 23. In this case, the center point P of the range sensor 5
The position and the posture of are acquired as the position and the posture of the list unit 3, and are stored in the position storage unit 18. On the other hand, the range sensor 5 acquires the shape data of the work 6. This shape data also includes information on the distance from the center point P of the range sensor 5 to the work 6. Range sensor 5
The signal from is taken into the sensor data processing unit 14 on the basis of the synchronization signal, subjected to preprocessing such as noise removal, and transferred to the sensor data determination unit 16. The sensor data discriminating unit 16 extracts a notable characteristic shape of the work 6 from the transferred data and discriminates it as a point of interest. The determination result includes coordinate information about the extracted target point in the coordinate system having the center point P of the range sensor 5 as the origin. The processing result of the sensor data discriminating unit 16 is sent to the sensor data display unit 15 to be displayed to assist the teaching work, and at the same time,
It is sent to the absolute position calculation unit 17.

In the absolute position calculation unit 17, the position storage unit 18
The teaching data, that is, the absolute position of the point of interest, can be obtained from the position / orientation data of the list unit 3 and the determination result from the sensor data determination unit 16 stored in the. Position storage unit 18
The position / orientation data stored in the
The position and orientation of the center point P of the range sensor 5 are expressed in the absolute coordinate system, and the data from the sensor data discriminating unit 16 is described in the coordinate system at the center point P of the range sensor 5. Therefore, the position / orientation data of the wrist unit 3 is R
(X _R , Y _R , Z _R , α, β, γ)
The data string from 6 (the data of a plurality of points of interest arranged) is S (x _i , y _i , z _i ) (where 1 ≦ i ≦
n), the teaching point data string (X _ti , Y _ti ,
Z _ti ) can be easily obtained by the following equation. The absolute position calculation unit 17 calculates the teaching point data string based on this formula. Here, n is the number of sensor data, that is, the number of attention points extracted by the sensor data discriminating unit 16.

[0019]

[Equation 1] However,

[0020]

[Equation 2] Is.

As is clear from this equation, each element of the teaching point data string is the coordinate value of the extracted point of interest in the absolute coordinate system. A desired point of interest is selected from this teaching point data string and stored in the teaching data storage unit 19 as route teaching data. As the teaching posture, the posture data (α, β, γ) of the list unit 3 is used as it is. In this way, the teaching data is stored in the teaching data storage unit 19 and the robot is taught.

The basic operation of the teaching work using the direct teaching device of this embodiment has been described above. In this direct teaching device, the continuous teaching mode,
There are two modes, named point teaching mode, respectively. 4A and 4B are diagrams for explaining the continuous teaching mode and the point teaching mode, respectively.

In the continuous teaching mode, as shown in FIG. 4A, the teaching data is continuously acquired for the work 6 at an arbitrary cycle. In this mode, the teaching operator first positions the hand of the manipulator 1 near the position where the teaching is desired to start. Then, the hand of the manipulator 1 is moved to the teaching end position at an appropriate speed roughly on the target route. At this time, the operating range of the range sensor 5 is not deviated. As a result, the teaching data is continuously acquired by the above-described operation every time the sync signal is generated from the sync signal generator 13 at the preset sampling cycle. Depending on the type and shape of the work 6, it is possible to set a plurality of teaching start positions and teaching end positions and change the sampling cycle for generating the synchronization signal for each section.

In the point teaching mode, as shown in FIG. 4B, the hand of the manipulator 1 is moved to an arbitrary position to obtain teaching data for each point. This mode is effective when it is desired to acquire the data left over from the acquisition of the teaching points in the continuous teaching mode or to obtain partially detailed teaching data.

Next, another embodiment of the robot direct teaching apparatus of the present invention will be described with reference to FIGS. Each of the embodiments described here is an improvement of the direct teaching device of the above-described embodiment so that it is more suitable for the actual teaching work.

The one shown in FIG. 5 facilitates the teaching work by visualizing the one-dimensional point sequence data acquired by the range sensor 5. In this embodiment, a small display 22 mounted on an installation table 21 is connected to the controller 7 of the direct teaching device shown in FIG. The display 22 has a range sensor 5
The sensor data string acquired by is displayed. In the case of the continuous teaching mode described above, sensor data is acquired every moment, so the sensor data is displayed in a graph. Since the sensor data is displayed in this manner, it is possible to improve work efficiency by observing this data during teaching work.

The one shown in FIG. 6 is one in which the teaching data point sequence can be observed in real time during the teaching work. In this embodiment, a television camera 23, a calculator 24, and a display 25 are further added to the direct teaching device shown in FIG. The television camera 23 uses the wrist unit 3 of the manipulator 1 so that at least the range sensor 5 can acquire an image in a range in which data is acquired.
Is attached to. The actual image data of the work 6 from the television camera 23 is sent to the computer 24. From the controller 7, the position / orientation data of the list unit 3 and the teaching point data string are sent to the computer 24. The computer 24 performs coordinate conversion calculation of the teaching point data sequence based on the position / orientation data, and further performs calibration processing of the television camera 23. The following formulas show the calculation of coordinate conversion, and the symbols and the like are the same as in the above formulas.

[0028]

[Equation 3] Then, while displaying the actual image of the work 6 from the television camera 23 on the display 25, the teaching point data string after coordinate conversion and calibration is displayed on the actual screen by superimposing.
That is, as shown in FIG. 6, the teaching point data string is displayed as a locus 27 on the television image 26. With this configuration, the acquired teaching point data string can be observed in real time during the teaching work, and the teaching work can be easily corrected by feeding back this data. ..

[0029]

As described above, according to the present invention, the distance measuring means for contactlessly measuring the distance to the point of interest, the position of the manipulator, and the distance data measured by the distance measuring means are used. By providing the data calculation means for calculating the absolute position and using it as the teaching data, it is possible to perform the teaching without accurately positioning the hand of the manipulator, which enables easy operation and improves the efficiency of the teaching work. It has the effect of improving. Further, a visual sensor is used as the distance measuring means, and a sensor data discriminating means for extracting a characteristic shape to be noticed and discriminating it as a noticed point is provided, while tracking the noticed point extracted and discriminated by the sensor data discriminating means. By successively calculating the absolute position of the point of interest, there is an effect that the route teaching data can be easily acquired only by moving the manipulator along the target route.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a configuration of a robot system including a direct teaching device for a robot according to an exemplary embodiment of the present invention.

FIG. 2 is a block diagram showing a specific configuration of a controller.

FIG. 3 is a diagram for explaining the operation of the direct teaching device of the robot of FIG.

4A and 4B are diagrams illustrating a continuous teaching mode and a point teaching mode, respectively. To

FIG. 5 is a diagram illustrating a direct teaching device for a robot according to another embodiment of the present invention.

FIG. 6 is a diagram illustrating a robot direct teaching device according to still another embodiment of the present invention.

[Explanation of symbols]

 1 Manipulator 2 Arm 3 Wrist Section 4 Force Sensor 5 Range Sensor 6 Work 7 Controller 8 Control Section 9 Teaching Data Calculation Section 10 Force Detection Section 11 Coordinate Conversion Section 12 Position Detection Section 13 Sync Signal Generation Section 14 Sensor Data Processing Section 15 Sensor Data display unit 16 Sensor data determination unit 17 Absolute position calculation unit 18 Position storage unit 19 Teaching data storage unit 20 Teaching handle 21 Installation table 22,25 Display 23 Television camera 24 Computer 26 Television image 27 Locus

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Shuichi Ohara 1-6, Uchisaiwaicho, Chiyoda-ku, Tokyo Inside Nippon Telegraph and Telephone Corporation (72) Yoshimasa Yanagihara 1-6, Uchisaiwaicho, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corp. (72) Inventor Tadashi Mouri 1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corp.

Claims (5)

[Claims] 1. A direct teaching device for a robot, comprising: a distance measuring unit attached to a wrist unit of a manipulator of the robot to measure a distance to a point of interest on an object in a non-contact manner; A direct teaching device for a robot, comprising: data calculating means for calculating an absolute position of the point of interest from distance data measured by the distance measuring means, and using the absolute position as teaching data for the point of interest. 2. A direct teaching device for a robot, which is attached to a wrist portion of a manipulator of the robot,
A visual sensor that obtains data relating to the shape of the object and data relating to the distance to the object, data relating to the position and orientation of the wrist section, and data relating to the shape and distance obtained by the visual sensor A direct teaching device for a robot, comprising: a data calculation unit that calculates an absolute position of the target point and uses the absolute position as teaching data for the target point. 3. The robot teaching apparatus according to claim 2, further comprising a monitor for displaying an image signal from the visual sensor. 4. A sensor data discriminating means for extracting a characteristic shape to be noticed from the shape data observed by the visual sensor and discriminating it as a point of interest, and a data calculating means is extracted by the sensor data discriminating means. The direct teaching device for a robot according to claim 2, wherein the route teaching data can be acquired in accordance with the movement of the manipulator by sequentially calculating the absolute position of the point of interest while tracking the determined point of interest. 5. A television camera for observing an object, a display, and a computer for superimposing route teaching data on the real screen in real time while displaying the real screen observed by the TV camera on the display. The direct teaching device for a robot according to claim 4, further comprising: