JPH07104714B2 - Off-line teaching system for handling robot - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention displays a robot model and a work model on an image output device, and operates the robot model on the image output device to operate data of a handling robot. The present invention relates to an off-line teaching system of a handling robot for creating a robot.

[Background of the Invention]

Today, robots are used in various fields including the manufacturing industry, and contribute to automation and labor saving of production.

Of these methods of teaching the robot a work operation, offline teaching is preferable to online teaching because teaching can be performed without stopping the production line.

Examples of the above-mentioned offline teaching system include, for example, JP-A-61-113099 and JP-A-61-118081.
The one disclosed in Japanese Patent Laid-Open No. 61-120029 has been proposed.

In the systems disclosed in the above publications, the point of the tip of the robot arm displayed on the CRT display is moved, and the operation data is taught using this as a teaching point.

Therefore, the system described above is suitable for a robot integrally provided with a tool that replaces the tip of the robot arm, for example, a robot equipped with tools such as a spray gun and a welding torch for performing work such as painting, sealing, and welding. hand,
It is not suitable for an element separated from the robot body, that is, a handling robot used when moving or assembling a work.

This is because the concept of the operation of the robot accompanying the handling of the work is not embodied systematically in the above-mentioned conventional technology.

Therefore, an object of the present invention is to provide a teaching system that can easily perform offline teaching to a handling robot.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the main means adopted by the present invention is that the gist thereof is to display a robot model and a work model on an image output device and operate the robot model on the image output device. In a handling robot off-line teaching system for creating operation data of a handling robot, data relating to respective shapes of a first robot model not including a work model and the work model is combined, and the work model is used as the first robot. Second state of being combined with the model
Means for obtaining data on the robot model of
The second robot model combined by the combining means is operated, and the matching state of the data about the second robot model and the data about the work model corresponding to the work placed at an arbitrary position in the work space The second robot model is operated on the image output device according to the determination means that determines that the workpiece is gripped by the handling robot, and the operation data when the determination means determines that the workpiece is gripped. And a motion simulation means for simulating this motion, which is an offline teaching system for a handling robot.

[Action]

In the offline teaching system for the handling robot according to the present invention, first, the first model that does not include the work model
Of the robot model and the work model are combined to form a second model in which the work model is integrally combined with the first robot model.
Data is created for the robot model of. That is,
The work is defined as a component of the handling robot.

Subsequently, the second robot model combined as described above is operated on the image output device, and the second robot model is operated.
When the data about the robot model and the data about the work model corresponding to the work placed at an arbitrary position in the work space substantially match, it is determined that the handling robot grips the work.

The data at this time is stored as teaching data (operation data).

The operation of the handling robot can be checked by operating the second robot model on the image output device according to the operation data and simulating this operation.

〔Example〕

Embodiments embodying the present invention will be described below with reference to the accompanying drawings to provide an understanding of the present invention. The following examples are examples of embodying the present invention and are not of the nature to limit the technical scope of the present invention.

Here, FIG. 1 is an external view of an offline teaching system for a handling robot according to an embodiment of the present invention, FIG. 2 is a conceptual exploded perspective view of an example of the handling robot, and FIG. 3 is the handling robot. 1A and 1B are schematic views of the constituent hands, wherein FIG. 1A is a perspective view in a disassembled state, FIG. 1B is a perspective view in an assembled state, and FIG. Perspective view in the
4 is a schematic configuration diagram of the handling robot in a state of gripping a work, FIG. 5 is a flowchart schematically showing a processing procedure in the offline teaching system, and FIGS. 6 and 7 are the handling robots, respectively. FIG. 3 is a schematic configuration diagram of the handling robot for explaining motion teaching for the robot.

In FIG. 1, the offline teaching system 1 for the handling robot is a digitizer 2 and a keyboard 3.
, A CRT display 4 (image output device), a floppy disk device 5, and a computer 6 are basically configured.

From a hardware standpoint, these are similar to so-called personal computer systems (personal computers) and do not have peculiar components, so the facility burden is relatively small.

The off-line teaching system 1 is a system for performing off-line teaching when handling a work,
Processing functions related to work drawing input, processing functions related to robot and peripheral device input, processing functions for creating data related to robot motion teaching, processing functions related to motion simulation, processing functions related to teaching data output, and processing functions related to assistance. Have

Each of these processing functions is first described above as a processing menu.
Since it is displayed on the CRT display 4, the operator can select it arbitrarily.

The respective processing functions will be sequentially described below.

Processing Function for Inputting Work Drawing The work drawing input processing is processing for inputting the shape of the work using a drawing.

First, the operator sets a drawing of a work on the digitizer 2 and traces the drawing with the pen 2a to input a diagram. The process of inputting a line drawing from such a drawing is already CA
Techniques known in the field such as D can be applied.

When a plan view, a front view and a side view are input, the computer 6 creates a three-dimensional surface model and CR
A three-view drawing and a perspective view are displayed on the T display 4.

If the operator, while looking at the screen, makes a mistake in inputting a command from the keyboard 3 and corrects it, and finally confirms that the displayed three-view drawing and perspective view accurately represent the workpiece, A command is input from the keyboard 3 and the work data is stored in a file.

Robot and Peripheral Device Input Processing Robot and peripheral device input processing is the process of defining the dimensions (coordinate data, etc.) of the robot and the work, defining the peripheral device, etc., and is the robot model (first robot model) A three-dimensional view and a perspective view of the model are displayed on the CRT display 4.

Therefore, if there is a change in the dimensions of the robot or the work, the operator corrects the robot model or the work model on the CRT display 4 or represents the actual shape of the robot or the work by inputting a numerical value.

Then, when the input of the data of the robot, the work and the peripheral device is completed, the data is stored in the file.

Processing Function for Creating Data Related to Robot Motion Teaching This processing function is the most characteristic element in the offline teaching system, and the outline of the processing procedure is as follows. Data regarding the respective shapes of the work models are combined to create data regarding the second robot model in a state where the work model is integrally combined with the first robot model. That is, the work is defined as one component of the handling robot.

Subsequently, the second robot model combined as described above is operated on the CRT display 4,
When the data about the second robot model and the data about the work model corresponding to the work placed at an arbitrary position in the work space substantially match, it is determined that the work is gripped by the handling robot. .

The data at this time is stored in the file as teaching data (motion data).

Hereinafter, the points in the above configuration will be described in detail with reference to FIGS. 2 to 4 and 6.

The meaning of each symbol attached in each figure is as follows.

O _w : Origin in the world coordinate system (in the work area) O _r : Origin in the robot coordinate system here, Data indicating the relative relationship between the robot and the work, which is set in advance by a processing function related to peripheral device input.

In the present teaching system, the Euler angle is used to represent the posture.

The Euler angles give rotations about the Z axis, X axis, and Y axis of the coordinate system as α, β, and γ, respectively. When used for the actual posture calculation, it is handled as a 3 × 3 posture matrix using the following formula.

In this embodiment, the posture of the work, the posture of the teaching point of the robot, and the like are all given by this method. On the contrary, (α, β, γ) can be obtained from the 3 × 3 posture matrix.

In this embodiment, the Euler angle is used to display the posture, but in addition to this, the method using the direction cosine, the roll
There is a method of using pitch yaw. The hand model is created by combining the three-dimensional models input as individual parts on the base coordinate system Oh of the hand (see FIGS. 2 and 3 (a)). Each of the above parts has its own coordinate system, and when modeling, it is defined as a set of individual models based on the relative position / posture data of the base coordinate system of the hand and the coordinate system of each part. To be done.

These positional relationships are obtained by combining the models on the CRT display 4.

In addition to the above data, the hand model is based on the hand base of the midpoint A of the hand (this position data is represented by ( _Xt , _Yt , _Zt )) which is treated as the teaching point of the robot. It has the viewed position data as numerical data. (See FIG. 3 (b)).

This is the position vector And

The work to be handled is combined with the hand model defined as described above. Here, the position of the origin of the work model coordinate system in the hand coordinate system (X _w , Y _w ,
Z _w ) and the posture (α _w , β _w , γ _w ) are set. Then, from ((α _w , β _w , γ _w ), Is obtained.

That is, the work is handled as a part of the parts that make up the hand, and the handling method is the same as that of the parts that make up the hand (see FIG. 3C).

Subsequently, it is defined in what positional relationship the hand modeled as described above is connected to the tip of the wrist of the robot (that is, the attachment portion of the hand).

Here, (X _h , Y _h , Z _h ) and (α _h , β _h , γ _h ) are set. Then, based on (α _h , β _h , γ _h ), Is obtained.

The modeling at this time is specifically similar to the case of modeling the above-mentioned hand, and each component constituting the robot in the base coordinate system of the robot is combined on the CRT display. As one of the parts,
The model of the hand including the work defined as described above is combined with the wrist tip (see FIG. 2).

As a result, the second robot model in which the work models are integrally combined is defined.

Each data defined as above and the robot (6
Fig. 4 shows the relationship between the position and orientation of the axes.

From the following relationships, the position and orientation of the work coordinate system in the robot coordinate system is expressed as follows.

The position of teaching point A is It is represented by.

Next, a procedure for creating teaching data for gripping a work by the handling robot will be described with reference to FIG.

The robot model is operated with respect to the work model B arranged in the work space (world coordinate system), and the work model B ′ having the same shape as the work model B defined at the tip of the hand is used.
The robot is positioned by overlapping.

It becomes known when the work is placed Obtained from the formula The consistency state is checked based on the data of. That is,
The state when the data overlap is the posture required for handling.

The check is performed by using the formula: the position (X _p ′, Y _p ′, Z _p ′) in the world coordinate system of the workpiece and the posture (α
_{Since p} ′, β _p ′, γ _p ′) is obtained, the following equation is used and the robot model is operated until it is satisfied.

Note that the above ε indicates the allowable error.

When the above equation is satisfied, data for positioning the robot is obtained. As an example, the case of (i) a robot that uses θ _{1 to} θ ₆ as motion data (ii) the case of a robot that uses position data of the tip of the hand and posture data based on Euler angles as motion data is described.

(I) In the case of a robot in which θ _{1 to} θ ₆ are motion data, the position vector of the work when the formula is satisfied is Posture matrix And

Here, generally, the position vector of the robot 6-axis tip Since a method of obtaining the values θ _{1 to} θ ₆ of each axis of the robot from is known, θ ₁ to θ ₆ can be obtained from the equation.

(Ii) In the case of a robot that uses position data of the tip of the hand and posture data based on Euler angles as motion data Since a method for obtaining the Euler angle from the 3 × 3 posture matrix is known, the Euler angle can be obtained from the equation.

Also, from the formula Since we can find Is obtained.

Next, regarding other methods, a solution method will be described for the following problems that occur in the above-described method.

When multiple workpieces with the same shape are placed, which workpiece is to be compared with the coordinate system of the workpiece model?

As a modification, when multiple types of work are defined for one hand, which work should be compared?

The above problem can be solved as follows.

Check by comparing each point data of the work model to be handled and the work model placed.

That is, as a method of defining a shape when modeling a work, since the work defined by the hand and the work arranged to be handled are the same, the data should match.

Therefore, the two workpieces are checked for consistency by comparing data relating to respective points constituting them.

For example, in the above case, the work closest to the origin of the work model defined in the hand model is first selected, and the above-mentioned check is performed on the work. The above case can be dealt with by checking the origins of all the work models defined in the hand model and checking as described above.

As described above, since the gripping state of the handling robot with respect to the workpiece handling is confirmed, this system does not require any teaching for confirming the gripping state of the workpiece again.

Processing function related to motion simulation In motion simulation processing, the handling work is advanced by animation based on the data set up to now.

That is, in the case of reproducing the program taught to handle the work C in FIG. 7, first, the robot model is operated according to the teaching data up to the teaching point at which the work C is handled. This time,
Since the above work C has not been handled yet,
The part of the work in the robot model is not displayed (a).

When the robot model is moved to a position where the work C can be handled and the data for closing the hand is set, whether or not the work to be handled is arranged at that portion when the hand is closed is checked. After checking
A work model is displayed at the tip of the robot model,
The work model placed in advance is erased (b).

Furthermore, operate the robot model according to the teaching data,
When the robot moves to the teaching position where the hand open signal is set, the work model handled by the robot model is erased and a work model newly appears on the work coordinate system (C, D).

In the above process, the operation range of the robot is automatically checked, and if it exceeds the operation range, which arm of the robot exceeds the operation range is displayed in a distinguishable manner.

The operator pauses at any point during the simulation, magnifies a part of the image, or changes the viewpoint so that the robot's arm or hand interferes with other workpieces and the position / orientation etc. Can be checked.

If there is a part that exceeds the robot's movement range, if it finds interference with the robot, or if it finds any other undesirable movement, it stops the simulation at that point,
Data can be modified.

Then, by performing the motion simulation while making the above corrections, the motion data at the time of handling the work can be completed very easily, as if remote teaching is being performed.

If you are satisfied with the results of the motion simulation,
Put the data in a file.

Processing Function Related to Teaching Data Output The teaching data output processing is processing for editing and outputting preferable data obtained as a result of the operation simulation into teaching data.

The most preferable output means is to send the data directly to the teaching data buffer of the handling robot through a transmission line.

Since the handling robot stores the sent teaching data by interrupt processing, it does not hinder the work on the work.

Alternatively, the data may be output to a medium such as a cassette tape or a floppy disk so that the handling robot can read the cassette tape or the floppy disk.

Then, the teaching data is stored in a file.

Auxiliary processing function Auxiliary processing is to perform initialization processing of the data diskette and auxiliary processing such as shooting out the screen itself on the CRT display 4 to the XY plotter.

The processing procedure of the system configured as described above is schematically shown in FIG.

That is, work modeling, the work to be handled is modeled. The above work has a coordinate system (origin) in input units,
The three-dimensional data of each point is the value in this coordinate system.

Work placement Place the input work model in the work space. The work arrangement in this case is to set a relative positional relationship between the coordinate system (world coordinate system) in the work space and the coordinate system of each work model.

Hand modeling The hand part is modeled. Also, Is set.

Correlation between hand and work The relative relationship between the hand model and the work model is defined. That is, the work is defined as one component of the hand. here, To set.

Correlation between robot model and hand model How the hand model is attached is set at the tip of the robot model. here, Is set.

Instruction of operation The hand model and the robot model defined as described above are called on the CRT display, and the robot model is operated by superposing the handled work model on the arranged work model.

When the hand closing is set, the matching state of the work model is checked, and if it is within the allowable error, the posture of the robot model at that time is stored as teaching data of the handling robot. After that, the robot model is moved to a position where the work is to be moved, and teaching data is created.

Motion simulation Based on the teaching data set as above, CRT
A simulation is performed on the display 4.

Since the teaching system according to the present embodiment is configured as described above, offline teaching for the handling robot can be performed very easily.

Further, since the teaching mistake can be easily found and corrected by the operation simulation, the quality of teaching can be improved and the work efficiency can be improved.

〔The invention's effect〕

As described above, the present invention provides an offline teaching system for a handling robot that displays a robot model and a work model on an image output device and operates the robot model on the image output device to create operation data of the handling robot. First, in which the work model is not included
Combining the data relating to the respective shapes of the robot model and the work model to obtain data relating to the second robot model in a state where the work model is integrally combined with the first robot model; The second robot model combined by the combining means is operated, and from the matching state of the data on the second robot model and the data on the work model corresponding to the work placed at an arbitrary position in the work space. The second robot model is operated on the image output device according to a determination unit that determines that the work is gripped by the handling robot and operation data when the determination unit determines that the work is gripped. ,
Since the offline teaching system for the handling robot is provided with the motion simulation means for simulating this motion, the offline teaching for the handling robot can be performed very easily.

Further, since the teaching mistake can be easily found and corrected by the motion simulation, the quality of teaching can be improved and the work efficiency can be improved.

[Brief description of drawings]

FIG. 1 is an external view of an offline teaching system for a handling robot according to an embodiment of the present invention, FIG. 2 is a conceptual exploded perspective view of an example of the handling robot, and FIG. 3 is a hand that constitutes the handling robot. 2A is a perspective view in a disassembled state, FIG. 1B is a perspective view in an assembled state, and FIG. 1C is a state in which a work is gripped. FIG. 4 is a schematic configuration diagram of the handling robot in a state of gripping a work, FIG. 5 is a flowchart schematically showing a processing procedure in the offline teaching system, and FIGS. 6 and 7 are FIG. 3 is a schematic configuration diagram of a handling robot for explaining motion teaching to the handling robot. [Description of symbols] 1 ... Offline teaching system 2 ... Digitizer 3 ... Keyboard 4 ... CRT display (image output device) 5 ... Floppy disk device 6 ... Computer

Claims (1)

[Claims] 1. An offline teaching system for a handling robot, wherein a robot model and a work model are displayed on an image output device, and the robot model is operated on the image output device to create operation data of the handling robot. Data relating to the respective shapes of the first robot model and the work model which do not include the above are combined to obtain data relating to the second robot model in a state where the work model is integrally combined with the first robot model. The combination means and the second robot model combined by the combination means are operated, and the data about the second robot model and the data about the work model corresponding to the work placed at an arbitrary position in the work space. From the matching state with The second robot model is operated on the image output device according to the judgment means for judging that the workpiece is gripped, and the motion data when the judgment means judges that the workpiece is gripped, An offline teaching system for a handling robot, comprising: a motion simulation means for simulating.